source: lib/libtrace.h.in @ 24fe0f5

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Last change on this file since 24fe0f5 was f6f3ae5, checked in by Jacob Van Walraven <jcv9@…>, 2 years ago

Assertion cleanup

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1/*
2 * This file is part of libtrace
3 *
4 * Copyright (c) 2007-2015 The University of Waikato, Hamilton,
5 * New Zealand.
6 *
7 * Authors: Daniel Lawson
8 *          Perry Lorier
9 *          Shane Alcock
10 *          Richard Sanger
11 *
12 * All rights reserved.
13 *
14 * This code has been developed by the University of Waikato WAND
15 * research group. For further information please see http://www.wand.net.nz/
16 *
17 * libtrace is free software; you can redistribute it and/or modify
18 * it under the terms of the GNU General Public License as published by
19 * the Free Software Foundation; either version 2 of the License, or
20 * (at your option) any later version.
21 *
22 * libtrace is distributed in the hope that it will be useful,
23 * but WITHOUT ANY WARRANTY; without even the implied warranty of
24 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
25 * GNU General Public License for more details.
26 *
27 * You should have received a copy of the GNU General Public License
28 * along with libtrace; if not, write to the Free Software
29 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
30 *
31 * $Id$
32 *
33 */
34
35#ifndef LIBTRACE_H
36#define LIBTRACE_H
37
38/** @file
39 *
40 * @brief Trace file processing library header
41 *
42 * @author Daniel Lawson
43 * @author Perry Lorier
44 * @author Shane Alcock
45 * @author Richard Sanger
46 *
47 * @version $Id$
48 *
49 * This library provides a per packet interface into a trace file, or a live
50 * captures.  It supports ERF, DAG cards, PCAP, Linux and BSD native sockets,
51 * legacy ERF formats etc.
52 *
53 * @par Usage
54 * See the example/ directory in the source distribution for some simple
55 * examples
56 *
57 * @par Linking
58 * To use this library you need to link against libtrace by passing -ltrace
59 * to your linker.
60 *
61 * See libtrace_parallel.h for a description of the parallel API that allows
62 * programmers to spread packet processing across multiple threads.
63 *
64 */
65
66#include <sys/types.h>
67#include <stddef.h>
68#include <stdio.h>
69/* Compile time assertion. Sourced from:
70 * http://www.pixelbeat.org/programming/gcc/static_assert.html */
71#define ct_assert(e) extern char (*ct_assert(void)) [sizeof(char[1 - 2*!(e)])]
72
73#ifndef WIN32
74#include <sys/time.h>
75#endif
76
77/* Deal with missing byte order macros */
78#include <sys/param.h>
79
80#if defined(BYTE_ORDER) && !defined(__BYTE_ORDER)
81#define __BYTE_ORDER    BYTE_ORDER
82#endif
83
84#if defined(BIG_ENDIAN) && !defined(__BIG_ENDIAN)
85#define __BIG_ENDIAN    BIG_ENDIAN
86#endif
87
88#if defined(LITTLE_ENDIAN) && !defined(__LITTLE_ENDIAN)
89#define __LITTLE_ENDIAN LITTLE_ENDIAN
90#endif
91
92#ifdef WIN32
93#   include <winsock2.h>
94#   include <ws2tcpip.h>
95    typedef short sa_family_t;
96    /* Make up for a lack of stdbool.h */
97#    define bool signed char
98#    define false 0
99#    define true 1
100#    if !defined(ssize_t)
101     /* XXX: Not 64-bit safe! */
102#    define ssize_t int
103#    endif   
104#else
105#    include <netinet/in.h>
106
107#ifndef __cplusplus
108#    include <stdbool.h>
109#endif
110
111#    include <sys/types.h>
112#    include <sys/socket.h>
113#endif
114
115/** API version as 2 byte hex digits, eg 0xXXYYZZ */
116#define LIBTRACE_API_VERSION \
117            ((@LIBTRACE_MAJOR@<<16)|(@LIBTRACE_MID@<<8)|(@LIBTRACE_MINOR@))
118
119/** This used to be replaced with the current SVN revision number when
120 * 'make dist' was invoked to create a distributable tarball. We don't use
121 * SVN anymore and there probably isn't any need to know the exact revision
122 * number either these days. */
123#define LIBTRACE_SVN_REVISION LIBTRACE_API_VERSION
124
125/** DAG driver version installed on the current system */
126#define DAG_DRIVER_V "@DAG_VERSION_NUM@"
127
128/**
129  * A version of assert that always runs the first argument even
130  * when not debugging, however only asserts the condition if debugging
131  * Intended for use mainly with pthread locks etc. which have error
132  * returns but *should* never actually fail.
133  */
134#ifdef NDEBUG
135#define ASSERT_RET(run, cond) run
136#else
137#define ASSERT_RET(run, cond) assert(run cond)
138//#define ASSERT_RET(run, cond) run
139#endif
140   
141#ifdef __cplusplus
142extern "C" {
143#endif
144
145#ifdef _MSC_VER
146    /* define the following from MSVC's internal types */
147    typedef             __int8  int8_t;
148    typedef             __int16 int16_t;
149    typedef             __int32 int32_t;
150    typedef             __int64 int64_t;
151    typedef unsigned    __int8  uint8_t;
152    typedef unsigned    __int16 uint16_t;
153    typedef unsigned    __int32 uint32_t;
154    typedef unsigned    __int64 uint64_t;
155   
156    /* Windows pads bitfields out to to the size of their parent type
157     * however gcc warns that this doesn't meet with the iso C specification
158     * so produces warnings for this behaviour.  sigh.
159     */
160    #define LT_BITFIELD8        uint8_t
161    #define LT_BITFIELD16       uint16_t
162    #define LT_BITFIELD32       uint32_t
163    #define LT_BITFIELD64       uint64_t
164#else
165    #ifdef HAVE_STDINT_H
166        #   include <stdint.h>
167    #endif
168    /* GCC warns if the bitfield type is not "unsigned int", however windows
169     * generates incorrect code for this (see above), so we define these
170     * macros.  How Hideous.  So much for C's portability.
171     */
172    #define LT_BITFIELD8        unsigned int
173    #define LT_BITFIELD16       unsigned int
174    #define LT_BITFIELD32       unsigned int
175    #define LT_BITFIELD64       unsigned int
176#endif
177
178/* Ensure these gcc optimisation attributes are defined consistently,
179 * without requiring users to need to have access to the config.h
180 * generated by running configure.
181 */
182
183#define LT_USE_PACKED @HAVE_ATTRIBUTE_PACKED@
184#define LT_USE_UNUSED @HAVE_ATTRIBUTE_UNUSED@
185#define LT_USE_DEPRECATED @HAVE_ATTRIBUTE_DEPRECATED@
186#define LT_USE_PURE @HAVE_ATTRIBUTE_PURE@
187#define LT_USE_PRINTF @HAVE_ATTRIBUTE_FORMAT@
188#define LT_USE_VISIBILITY @HAVE_VISIBILITY@
189
190#if LT_USE_PACKED
191#  define PACKED __attribute__((packed))
192#else
193#  define PACKED
194#endif
195
196#if LT_USE_UNUSED
197#  define UNUSED __attribute__((unused))
198#else
199#  define UNUSED
200#endif
201
202#if LT_USE_DEPRECATED
203#  define DEPRECATED __attribute__((deprecated))
204#else
205#  define DEPRECATED
206#endif
207
208#if LT_USE_PURE
209#  define SIMPLE_FUNCTION __attribute__((pure))
210#else
211#  define SIMPLE_FUNCTION
212#endif
213
214#if LT_USE_PRINTF
215#  define PRINTF(formatpos, argpos) __attribute__((format(printf,formatpos, argpos)))
216#else
217#  define PRINTF(formatpos, argpos)
218#endif
219
220#ifndef CACHE_LINE_SIZE
221#define CACHE_LINE_SIZE 64
222#endif
223#define ALIGN_STRUCT(x) __attribute__((aligned(x)))
224
225#ifdef _MSC_VER
226    #ifdef LT_BUILDING_DLL
227        #define DLLEXPORT __declspec(dllexport)
228    #else
229        #define DLLEXPORT __declspec(dllimport)
230    #endif
231    #define DLLLOCAL
232#else
233    #ifndef DLLEXPORT
234        #if LT_USE_VISIBILITY && LT_BUILDING_DLL
235            #define DLLEXPORT __attribute__ ((visibility("default")))
236            #define DLLLOCAL __attribute__ ((visibility("hidden")))
237        #else
238            #define DLLEXPORT
239            #define DLLLOCAL
240        #endif
241    #endif
242#endif
243
244
245/** Opaque structure holding information about an output trace */
246typedef struct libtrace_out_t libtrace_out_t;
247
248/** Opaque structure holding information about a trace */
249typedef struct libtrace_t libtrace_t;
250
251/** Opaque structure holding information about a bpf filter */
252typedef struct libtrace_filter_t libtrace_filter_t;
253
254/** Opaque structure holding information about libtrace thread */
255typedef struct libtrace_thread_t libtrace_thread_t;
256
257/** Opaque structure holding callback functions for libtrace threads */
258typedef struct callback_set libtrace_callback_set_t;
259
260/** If the packet has allocated its own memory the buffer_control should be
261 * set to TRACE_CTRL_PACKET, so that the memory will be freed when the packet
262 * is destroyed. If the packet has been zero-copied out of memory owned by
263 * something else, e.g. a DAG card, it should be TRACE_CTRL_EXTERNAL.
264 *
265 * @note The letters p and e are magic numbers used to detect if the packet
266 * wasn't created properly.
267 */
268typedef enum {
269        TRACE_CTRL_PACKET='p',  /**< Buffer memory is owned by the packet */
270        TRACE_CTRL_EXTERNAL='e' /**< Buffer memory is owned by an external source */
271} buf_control_t;
272
273/** The size of a packet's buffer when managed by libtrace */
274#define LIBTRACE_PACKET_BUFSIZE 65536
275
276/** Libtrace error information */
277typedef struct trace_err_t{
278        int err_num;            /**< error code */
279        char problem[1024];     /**< the format, uri etc that caused the error for reporting purposes */
280} libtrace_err_t;
281
282/** Enumeration of error codes */
283enum {
284        /** No Error has occurred.... yet. */
285        TRACE_ERR_NOERROR       = 0,
286        /** The URI passed to trace_create() is unsupported, or badly formed */
287        TRACE_ERR_BAD_FORMAT    = -1,
288        /** The trace failed to initialise */
289        TRACE_ERR_INIT_FAILED   = -2,
290        /** Unknown config option */
291        TRACE_ERR_UNKNOWN_OPTION= -3,
292        /** This output uri cannot write packets of this type */
293        TRACE_ERR_NO_CONVERSION = -4,
294        /** This packet is corrupt, or unusable for the action required */
295        TRACE_ERR_BAD_PACKET    = -5,
296        /** Option known, but unsupported by this format */
297        TRACE_ERR_OPTION_UNAVAIL= -6,
298        /** This feature is unsupported */
299        TRACE_ERR_UNSUPPORTED   = -7,
300        /** Illegal use of the API */
301        TRACE_ERR_BAD_STATE     = -8,
302        /** Failed to compile a BPF filter */
303        TRACE_ERR_BAD_FILTER    = -9,
304        /** RT communication breakdown */
305        TRACE_ERR_RT_FAILURE    = -10,
306        /** Compression format unsupported */
307        TRACE_ERR_UNSUPPORTED_COMPRESS  = -11,
308        /** Wandio has returned an error */
309        TRACE_ERR_WANDIO_FAILED = -12,
310        /** Input URI (file) not found */
311        TRACE_ERR_URI_NOT_FOUND = -13,
312        /** NULL passed to create trace **/
313        TRACE_ERR_URI_NULL = -14,
314        /** NULL trace passed to trace_start **/
315        TRACE_ERR_NULL_TRACE = -15,
316        /** Unable to finish last packet in trace_pause **/
317        TRACE_ERR_PAUSE_FIN = -16,
318        /** Packet is NULL **/
319        TRACE_ERR_NULL_PACKET = -17,
320        /** Filter is NULL **/
321        TRACE_ERR_NULL_FILTER = -18,
322        /** Buffer is NULL **/
323        TRACE_ERR_NULL_BUFFER = -19,
324        /** Trace stats err **/
325        TRACE_ERR_STAT = -20,
326        /** Unable to create deadtrace **/
327        TRACE_ERR_CREATE_DEADTRACE = -21,
328        /** Bad linktype **/
329        TRACE_ERR_BAD_LINKTYPE = -22,
330        /** Bad IO for the trace **/
331        TRACE_ERR_BAD_IO = -23,
332        /** Trace has bad header **/
333        TRACE_ERR_BAD_HEADER = -24,
334        /** Trace err seeking by erf **/
335        TRACE_ERR_SEEK_ERF = -25,
336        /** Trace err combiner **/
337        TRACE_ERR_COMBINER = -26,
338        /** Error pausing processing thread **/
339        TRACE_ERR_PAUSE_PTHREAD = -27,
340        /** Error with trace thread **/
341        TRACE_ERR_THREAD = -28,
342        /** Thread in unexpecting state **/
343        TRACE_ERR_THREAD_STATE = -29,
344        /** Trace configuration error **/
345        TRACE_ERR_CONFIG = -30,
346        /** NULL passed misc **/
347        TRACE_ERR_NULL = -31,
348};
349
350/** Enumeration of DLTs supported by libtrace
351 */
352typedef enum {
353        /* Special value used to indicate a failure to convert to libtrace
354         * DLT */
355        TRACE_DLT_ERROR = -1,
356
357        /** pcap documents this as having the Address Family value in host
358          * byte order as the framing.  Ugly? Yes.
359          */
360        TRACE_DLT_NULL = 0,
361        TRACE_DLT_EN10MB = 1,
362        TRACE_DLT_PPP = 9,
363        TRACE_DLT_ATM_RFC1483 = 11,
364
365        /** Ok, so OpenBSD has a different value for DLT_RAW as the rest of
366         * the planet, so detect this.  When reading to/from files we should
367         * be using TRACE_DLT_LINKTYPE_RAW instead. When talking about DLT's
368         * inside libtrace tho, we should be using /these/ DLT's.
369         */
370#ifdef __OpenBSD__
371        TRACE_DLT_OPENBSD_LOOP=12,
372        TRACE_DLT_RAW = 14,
373#else
374        TRACE_DLT_RAW = 12,
375        TRACE_DLT_OPENBSD_LOOP = 108,
376#endif
377        TRACE_DLT_PPP_SERIAL = 50,
378        TRACE_DLT_LINKTYPE_RAW = 101, /**< See TRACE_DLT_RAW for explanations of pain. */
379        TRACE_DLT_C_HDLC = 104,
380        TRACE_DLT_IEEE802_11 = 105,
381        TRACE_DLT_LINUX_SLL = 113,
382        TRACE_DLT_PFLOG = 117,
383        TRACE_DLT_IEEE802_11_RADIO = 127 /**< Radiotap */
384} libtrace_dlt_t ;
385
386/** Enumeration of link layer types supported by libtrace */
387typedef enum {
388       TRACE_TYPE_CONTENT_INVALID = -2, /**< Packet contents are not valid */
389       TRACE_TYPE_UNKNOWN = -1,         /**< Unable to determine link type */
390    /* TRACE_TYPE_LEGACY = 0            Obsolete */
391       TRACE_TYPE_HDLC_POS = 1,         /**< HDLC over POS */
392       TRACE_TYPE_ETH = 2,              /**< 802.3 style Ethernet */
393       TRACE_TYPE_ATM = 3,              /**< ATM frame */
394       TRACE_TYPE_80211 = 4,            /**< 802.11 frames */
395       TRACE_TYPE_NONE = 5,             /**< Raw IP frames */
396       TRACE_TYPE_LINUX_SLL = 6,        /**< Linux "null" framing */
397       TRACE_TYPE_PFLOG = 7,            /**< FreeBSD's PFlog */
398    /* TRACE_TYPE_LEGACY_DEFAULT        Obsolete */
399       TRACE_TYPE_POS = 9,              /**< Packet-over-SONET */
400    /* TRACE_TYPE_LEGACY_ATM            Obsolete */
401    /* TRACE_TYPE_LEGACY_ETH            Obsolete */
402       TRACE_TYPE_80211_PRISM = 12,     /**< 802.11 Prism frames */
403       TRACE_TYPE_AAL5 = 13,            /**< ATM Adaptation Layer 5 frames */
404       TRACE_TYPE_DUCK = 14,         /**< Pseudo link layer for DUCK packets */
405       TRACE_TYPE_80211_RADIO = 15,  /**< Radiotap + 802.11 */
406       TRACE_TYPE_LLCSNAP = 16,      /**< Raw LLC/SNAP */
407       TRACE_TYPE_PPP = 17,          /**< PPP frames */
408       TRACE_TYPE_METADATA = 18,        /**< WDCAP-style meta-data */
409       TRACE_TYPE_NONDATA = 19,         /**< Not a data packet */
410       TRACE_TYPE_OPENBSD_LOOP = 20,    /**< OpenBSD loopback */
411       TRACE_TYPE_ERF_META = 21, /**< ERF Provenance metadata record */
412       TRACE_TYPE_ETSILI = 22   /**< ETSI Lawful Intercept */
413} libtrace_linktype_t;
414
415/** RT protocol base format identifiers.
416 * This is used to describe the capture format of the packet is being sent
417 * using the RT protocol.
418 */
419enum base_format_t {
420        TRACE_FORMAT_ERF          =1,   /**< ERF (DAG capture format) */
421        TRACE_FORMAT_PCAP         =2,   /**< Live PCAP capture */
422        TRACE_FORMAT_PCAPFILE     =3,   /**< PCAP trace file */
423        TRACE_FORMAT_WAG          =4,   /**< WAG live capture (Obsolete) */
424        TRACE_FORMAT_RT           =5,   /**< RT network protocol */
425        TRACE_FORMAT_LEGACY_ATM   =6,   /**< Legacy ERF for ATM capture */
426        TRACE_FORMAT_LEGACY_POS   =7,   /**< Legacy ERF for POS capture */
427        TRACE_FORMAT_LEGACY_ETH   =8,   /**< Legacy ERF for ETH capture */
428        TRACE_FORMAT_LINUX_NATIVE =9,   /**< Linux native interface capture */
429        TRACE_FORMAT_DUCK         =10,  /**< DAG Clock information */
430        TRACE_FORMAT_BPF          =11,  /**< BSD native interface capture */
431        TRACE_FORMAT_TSH          =12,  /**< TSH trace format */
432        TRACE_FORMAT_ATMHDR       =13,  /**< Legacy ATM header capture */
433        TRACE_FORMAT_LEGACY_NZIX  =14,  /**< Legacy format used for NZIX traces */
434        TRACE_FORMAT_LINUX_RING   =15,  /**< Linux native interface capture PACKET_MMAP */
435        TRACE_FORMAT_RAWERF       =16,  /**< Special format for reading uncompressed ERF traces without checking for compression */
436        TRACE_FORMAT_DPDK     =17, /**< The Intel Data Plane Development Kit format */
437        TRACE_FORMAT_PCAPNG     =18,    /**< PCAP-NG trace file */
438        TRACE_FORMAT_NDAG       =19,    /**< DAG multicast over a network */
439        TRACE_FORMAT_DPDK_NDAG       =20,    /**< DAG multicast over a network, received via DPDK */
440        TRACE_FORMAT_ETSILIVE     =21,  /**< ETSI LI over a network */
441        TRACE_FORMAT_UNKNOWN      =22,  /** Unknown format */
442};
443
444/** RT protocol packet types */
445typedef enum {
446        TRACE_RT_HELLO          =1, /**< Connection accepted */
447        TRACE_RT_START          =2, /**< Request for data transmission to begin
448                                    */
449        TRACE_RT_ACK            =3, /**< Data acknowledgement */
450        TRACE_RT_STATUS         =4, /**< Fifo status packet */
451        TRACE_RT_DUCK           =5, /**< Dag duck info packet */
452        TRACE_RT_END_DATA       =6, /**< Server is exiting message */
453        TRACE_RT_CLOSE          =7, /**< Client is exiting message */
454        TRACE_RT_DENY_CONN      =8, /**< Connection has been denied */
455        TRACE_RT_PAUSE          =9, /**< Request server to suspend sending data
456                                     */
457        TRACE_RT_PAUSE_ACK      =10,/**< Server is paused message */
458        TRACE_RT_OPTION         =11,/**< Option request */
459        TRACE_RT_KEYCHANGE      =12,/**< Anonymisation key has changed */
460        TRACE_RT_DUCK_2_4       =13,/**< Dag 2.4 Duck */
461        TRACE_RT_DUCK_2_5       =14,/**< Dag 2.5 Duck */
462        TRACE_RT_LOSTCONN       =15,/**< Lost connection to server */
463        TRACE_RT_SERVERSTART    =16,/**< Reliable server has been restarted */
464        TRACE_RT_CLIENTDROP     =17,/**< Reliable client was lost */
465        TRACE_RT_METADATA       =18,/**< Packet contains server meta-data */
466        TRACE_RT_DUCK_5_0       =19,/**< Dag 5.0 Duck */
467        TRACE_RT_PCAPNG_META    =20,/**< Metadata for a PCAP NG input source */
468
469        /** Not actually used - all DATA types begin from this value */
470        TRACE_RT_DATA_SIMPLE    = 1000,
471       
472        /** RT is encapsulating an ERF capture record */
473        TRACE_RT_DATA_ERF       =TRACE_RT_DATA_SIMPLE+TRACE_FORMAT_ERF,
474        /** RT is encapsulating a WAG capture record */
475        TRACE_RT_DATA_WAG       =TRACE_RT_DATA_SIMPLE+TRACE_FORMAT_WAG,
476        /** RT is encapsulating a Legacy ATM capture record */
477        TRACE_RT_DATA_LEGACY_ATM=TRACE_RT_DATA_SIMPLE+TRACE_FORMAT_LEGACY_ATM,
478        /** RT is encapsulating a Legacy POS capture record */
479        TRACE_RT_DATA_LEGACY_POS=TRACE_RT_DATA_SIMPLE+TRACE_FORMAT_LEGACY_POS,
480        /** RT is encapsulating a Legacy ETH capture record */
481        TRACE_RT_DATA_LEGACY_ETH=TRACE_RT_DATA_SIMPLE+TRACE_FORMAT_LEGACY_ETH,
482        /** RT is encapsulating a Linux native capture record */
483        TRACE_RT_DATA_LINUX_NATIVE=TRACE_RT_DATA_SIMPLE+TRACE_FORMAT_LINUX_NATIVE,
484        /** RT is encapsulating a BSD native capture record */
485        //TRACE_RT_DATA_BPF       =TRACE_RT_DATA_SIMPLE+TRACE_FORMAT_BPF,
486        /** RT is encapsulating a TSH capture record */
487        TRACE_RT_DATA_TSH       =TRACE_RT_DATA_SIMPLE+TRACE_FORMAT_TSH,
488        /** RT is encapsulating an ATM header capture record */
489        TRACE_RT_DATA_ATMHDR = TRACE_RT_DATA_SIMPLE + TRACE_FORMAT_ATMHDR,
490        /** RT is encapsulating a Legacy NZIX capture record */
491        TRACE_RT_DATA_LEGACY_NZIX=TRACE_RT_DATA_SIMPLE + TRACE_FORMAT_LEGACY_NZIX,
492        /** RT is encapsulating a Linux native PACKET_MMAP capture record */
493        TRACE_RT_DATA_LINUX_RING=TRACE_RT_DATA_SIMPLE+TRACE_FORMAT_LINUX_RING,
494    /** RT is encapsulating a Intel DPDK capture record */
495        TRACE_RT_DATA_DPDK=TRACE_RT_DATA_SIMPLE+TRACE_FORMAT_DPDK,
496
497        TRACE_RT_DATA_ETSILI = TRACE_RT_DATA_SIMPLE + TRACE_FORMAT_ETSILIVE,
498
499        /** As PCAP does not store the linktype with the packet, we need to
500         * create a separate RT type for each supported DLT, starting from
501         * this value */
502        TRACE_RT_DATA_DLT               = 2000,
503        /** RT is encapsulating a PCAP capture record with a NULL linktype */
504        TRACE_RT_DLT_NULL               =TRACE_RT_DATA_DLT+TRACE_DLT_NULL,
505        /** RT is encapsulating a PCAP capture record with an Ethernet
506         * linktype */
507        TRACE_RT_DLT_EN10MB             =TRACE_RT_DATA_DLT+TRACE_DLT_EN10MB,
508        /** RT is encapsulating a PCAP capture record with an 802.11
509         * linktype */
510        TRACE_RT_DLT_IEEE802_11         =TRACE_RT_DATA_DLT+TRACE_DLT_IEEE802_11,
511        /** RT is encapsulating a PCAP capture record with a Linux SLL
512         * linktype */
513        TRACE_RT_DLT_LINUX_SLL          =TRACE_RT_DATA_DLT+TRACE_DLT_LINUX_SLL,
514        /** RT is encapsulating a PCAP capture record with a PFlog linktype */
515        TRACE_RT_DLT_PFLOG              =TRACE_RT_DATA_DLT+TRACE_DLT_PFLOG,
516        /** RT is encapsulating a PCAP capture record with an AAL5 linktype */
517        TRACE_RT_DLT_ATM_RFC1483        =TRACE_RT_DATA_DLT+TRACE_DLT_ATM_RFC1483,
518        /** Unused value marking the end of the valid range for PCAP RT
519         * encapsulation */
520        TRACE_RT_DATA_DLT_END           = 2999,
521        /** BPF does not store the linktype with the packet, so we need a
522         * separate RT type for each supported DLT. This value represents the
523         * starting point */
524        TRACE_RT_DATA_BPF               = 3000,
525
526        TRACE_RT_BPF_NULL               = TRACE_RT_DATA_BPF+TRACE_DLT_NULL,
527        TRACE_RT_BPF_EN10MB             = TRACE_RT_DATA_BPF+TRACE_DLT_EN10MB,
528        TRACE_RT_BPF_IEEE802_11         = TRACE_RT_DATA_BPF+TRACE_DLT_IEEE802_11,
529        TRACE_RT_BPF_PFLOG              =TRACE_RT_DATA_BPF+TRACE_DLT_PFLOG,
530        TRACE_RT_BPF_ATM_RFC1483        =TRACE_RT_DATA_BPF+TRACE_DLT_ATM_RFC1483,
531
532        TRACE_RT_DATA_BPF_END           = 3999,
533
534        TRACE_RT_DATA_PCAPNG            = 4000,
535        TRACE_RT_DATA_PCAPNG_END        = 4499,
536        /** Unused value marking the end of the valid range for all RT packet
537         * types */
538        TRACE_RT_LAST                   = 4500
539} libtrace_rt_types_t;
540
541/** IP Protocol values */
542typedef enum {
543        TRACE_IPPROTO_IP        = 0,    /**< IP pseudo protocol number */
544        TRACE_IPPROTO_ICMP      = 1,    /**< Internet Control Message protocol */
545        TRACE_IPPROTO_IGMP      = 2,    /**< Internet Group Management Protocol */
546        TRACE_IPPROTO_IPIP      = 4,    /**< IP encapsulated in IP */
547        TRACE_IPPROTO_TCP       = 6,    /**< Transmission Control Protocol */
548        TRACE_IPPROTO_UDP       = 17,   /**< User Datagram Protocol */
549        TRACE_IPPROTO_IPV6      = 41,   /**< IPv6 over IPv4 */
550        TRACE_IPPROTO_ROUTING   = 43,   /**< IPv6 Routing header */
551        TRACE_IPPROTO_FRAGMENT  = 44,   /**< IPv6 Fragmentation header */
552        TRACE_IPPROTO_RSVP      = 46,   /**< Resource Reservation Protocol */
553        TRACE_IPPROTO_GRE       = 47,   /**< General Routing Encapsulation */
554        TRACE_IPPROTO_ESP       = 50,   /**< Encapsulated Security Payload [RFC2406] */
555        TRACE_IPPROTO_AH        = 51,   /**< Authentication Header [RFC2402] */
556        TRACE_IPPROTO_ICMPV6    = 58,   /**< ICMPv6 */
557        TRACE_IPPROTO_NONE      = 59,   /**< IPv6 no next header */
558        TRACE_IPPROTO_DSTOPTS   = 60,   /**< IPv6 destination options */
559        TRACE_IPPROTO_OSPF      = 89,   /**< Open Shortest Path First routing protocol */
560        TRACE_IPPROTO_PIM       = 103,  /**< Protocol Independant Multicast */
561        TRACE_IPPROTO_SCTP      = 132   /**< Stream Control Transmission Protocol */
562} libtrace_ipproto_t;
563
564/** Ethertypes supported by Libtrace */
565typedef enum {
566        /* Numbers <=1500 are of course, LLC/SNAP */
567        TRACE_ETHERTYPE_LOOPBACK= 0x0060,       /**< Ethernet Loopback */
568        TRACE_ETHERTYPE_IP      = 0x0800,       /**< IPv4 */
569        TRACE_ETHERTYPE_ARP     = 0x0806,       /**< Address resolution protocol */
570        TRACE_ETHERTYPE_RARP    = 0x8035,       /**< Reverse ARP */
571        TRACE_ETHERTYPE_8021Q   = 0x8100,       /**< 802.1q VLAN Extended Header */
572        TRACE_ETHERTYPE_IPV6    = 0x86DD,       /**< IPv6 */
573        TRACE_ETHERTYPE_MPLS    = 0x8847,       /**< MPLS Unicast traffic */
574        TRACE_ETHERTYPE_MPLS_MC = 0x8848,       /**< MPLS Multicast traffic */
575        TRACE_ETHERTYPE_PPP_DISC= 0x8863,       /**< PPPoE Service Discovery */
576        TRACE_ETHERTYPE_PPP_SES = 0x8864        /**< PPPoE Session Messages */
577} libtrace_ethertype_t;
578
579/** The libtrace packet structure. Applications shouldn't be
580 * meddling around in here
581 */
582typedef struct libtrace_packet_t {
583        struct libtrace_t *trace;       /**< Pointer to the trace */
584        void *header;                   /**< Pointer to the framing header */
585        void *payload;                  /**< Pointer to the link layer */
586        void *buffer;                   /**< Allocated buffer */
587        libtrace_rt_types_t  type;      /**< RT protocol type for the packet */
588        buf_control_t buf_control;      /**< Describes memory ownership */
589        int capture_length;             /**< Cached capture length */
590        int wire_length;                /**< Cached wire length */
591        int payload_length;             /**< Cached payload length */
592        int framing_length;             /**< Cached framing length */
593        void *l2_header;                /**< Cached link header */
594        libtrace_linktype_t link_type;  /**< Cached link type */
595        uint32_t l2_remaining;          /**< Cached link remaining */
596        void *l3_header;                /**< Cached l3 header */
597        uint16_t l3_ethertype;          /**< Cached l3 ethertype */
598        uint32_t l3_remaining;          /**< Cached l3 remaining */
599        void *l4_header;                /**< Cached transport header */
600        uint8_t transport_proto;        /**< Cached transport protocol */
601        uint32_t l4_remaining;          /**< Cached transport remaining */
602        uint64_t order; /**< Notes the order of this packet in relation to the input */
603        uint64_t hash; /**< A hash of the packet as supplied by the user */
604        int error; /**< The error status of pread_packet */
605        uint64_t internalid;            /** Internal identifier for the pkt */
606        void *srcbucket;
607
608        pthread_mutex_t ref_lock;       /**< Lock for reference counter */
609        int refcount;                 /**< Reference counter */
610        int which_trace_start;          /**< Used to match packet to a started instance of the parent trace */
611
612} libtrace_packet_t;
613
614#define IS_LIBTRACE_META_PACKET(packet) (packet->type < TRACE_RT_DATA_SIMPLE)
615
616
617/** Trace directions.
618 * Note that these are the directions used by convention. More directions
619 * are possible, not just these 3, and that they may not conform to this
620 * convention.
621 */
622typedef enum {
623        TRACE_DIR_OUTGOING = 0,         /**< Packets originating "inside" */
624        TRACE_DIR_INCOMING = 1,         /**< Packets originating "outside" */
625        TRACE_DIR_OTHER    = 2,         /**< Packets with an unknown direction, or one that's unknown */
626        TRACE_DIR_UNKNOWN = -1,         /**< No direction information available */
627} libtrace_direction_t;
628
629/** Enumeration of Radiotap fields */
630typedef enum {
631    TRACE_RADIOTAP_TSFT = 0, /**< Timer synchronisation function, in microseconds (uint64) */
632    TRACE_RADIOTAP_FLAGS = 1, /**< Wireless flags (uint8) */
633    TRACE_RADIOTAP_RATE = 2, /**< Bitrate in units of 500kbps (uint8) */
634    TRACE_RADIOTAP_CHANNEL = 3, /**< Frequency in MHz (uint16) and channel flags (uint16) */
635    TRACE_RADIOTAP_FHSS = 4, /**< FHSS hop set (uint8) and hopping pattern (uint8) */
636    TRACE_RADIOTAP_DBM_ANTSIGNAL = 5, /**< Signal power in dBm (int8) */
637    TRACE_RADIOTAP_DBM_ANTNOISE = 6, /**< Noise power in dBm (int8) */
638    TRACE_RADIOTAP_LOCK_QUALITY = 7, /**< Barker Code lock quality (uint16) */
639    TRACE_RADIOTAP_TX_ATTENUATION = 8, /**< TX attenuation as unitless distance from max power (uint16) */
640    TRACE_RADIOTAP_DB_TX_ATTENUATION = 9, /**< TX attenuation as dB from max power (uint16) */
641    TRACE_RADIOTAP_DBM_TX_POWER = 10, /**< TX Power in dBm (int8) */
642    TRACE_RADIOTAP_ANTENNA = 11, /**< Antenna frame was rx'd or tx'd on (uint8) */
643    TRACE_RADIOTAP_DB_ANTSIGNAL = 12, /**< Signal power in dB from a fixed reference (uint8) */
644    TRACE_RADIOTAP_DB_ANTNOISE = 13, /**< Noise power in dB from a fixed reference (uint8) */
645    TRACE_RADIOTAP_RX_FLAGS = 14, /** Properties of received frame (uint16) */
646    TRACE_RADIOTAP_TX_FLAGS = 15, /** Properties of transmitted frame (uint16) */
647    TRACE_RADIOTAP_RTS_RETRIES = 16, /** Number of rts retries frame used (uint8) */
648    TRACE_RADIOTAP_DATA_RETRIES = 17, /** Number of unicast retries a transmitted frame used (uint8) */
649    TRACE_RADIOTAP_EXT = 31
650} libtrace_radiotap_field_t;
651
652
653/** @name Protocol structures
654 * These convenience structures provide portable versions of the headers
655 * for a variety of protocols.
656 * @{
657 */
658
659#ifdef WIN32
660#pragma pack(push)
661#pragma pack(1)
662#endif
663
664/** Generic IP header structure */
665typedef struct libtrace_ip
666{
667#if __BYTE_ORDER == __LITTLE_ENDIAN
668    LT_BITFIELD8 ip_hl:4;               /**< Header Length */
669    LT_BITFIELD8 ip_v:4;                /**< Version */
670#elif __BYTE_ORDER == __BIG_ENDIAN
671    LT_BITFIELD8 ip_v:4;                /**< Version */
672    LT_BITFIELD8 ip_hl:4;               /**< Header Length */
673#else
674#   error "Adjust your <bits/endian.h> defines"
675#endif
676    uint8_t  ip_tos;                    /**< Type of Service */
677    uint16_t ip_len;                    /**< Total Length */
678    int16_t  ip_id;                     /**< Identification */
679    uint16_t ip_off;                    /**< IP Fragment offset (and flags) */
680    uint8_t  ip_ttl;                    /**< Time to Live */
681    uint8_t  ip_p;                      /**< Protocol */
682    uint16_t ip_sum;                    /**< Checksum */
683    struct in_addr ip_src;              /**< Source Address */
684    struct in_addr ip_dst;              /**< Destination Address */
685} PACKED libtrace_ip_t;
686
687/** IPv6 header extension structure */
688typedef struct libtrace_ip6_ext
689{
690        uint8_t nxt;    /**< Next header */
691        uint8_t len;    /**< Length of the current header */
692} PACKED libtrace_ip6_ext_t;
693
694/** IPv6 fragmentation header */
695typedef struct libtrace_ip6_frag
696{
697        uint8_t nxt;    /**< Next header */
698        uint8_t res;    /**< Reserved */
699        uint16_t frag_off;      /**< Fragment Offset (includes M flag) */
700        uint32_t ident; /** Fragment identification */
701} PACKED libtrace_ip6_frag_t;
702
703/** Generic IPv6 header structure
704 *
705 * @note The flow label field also includes the Version and Traffic Class
706 * fields, because we haven't figured out a nice way to deal with fields
707 * crossing byte boundaries on both Big and Little Endian machines */
708typedef struct libtrace_ip6
709{
710    uint32_t flow;                      /**< Flow label */
711    uint16_t plen;                      /**< Payload length */
712    uint8_t nxt;                        /**< Next header */
713    uint8_t hlim;                       /**< Hop limit */
714    struct in6_addr ip_src;             /**< Source address */
715    struct in6_addr ip_dst;             /**< Destination address */
716} PACKED libtrace_ip6_t;
717
718/** Generic TCP header structure */
719typedef struct libtrace_tcp
720  {
721    uint16_t source;            /**< Source Port */
722    uint16_t dest;              /**< Destination port */
723    uint32_t seq;               /**< Sequence number */
724    uint32_t ack_seq;           /**< Acknowledgement Number */
725#  if __BYTE_ORDER == __LITTLE_ENDIAN
726    LT_BITFIELD8 ecn_ns:1;      /**< ECN Nonce Sum */
727    LT_BITFIELD8 res1:3;        /**< Reserved bits */
728    LT_BITFIELD8 doff:4;        /**< Data Offset */
729    LT_BITFIELD8 fin:1;         /**< FIN */
730    LT_BITFIELD8 syn:1;         /**< SYN flag */
731    LT_BITFIELD8 rst:1;         /**< RST flag */
732    LT_BITFIELD8 psh:1;         /**< PuSH flag */
733    LT_BITFIELD8 ack:1;         /**< ACK flag */
734    LT_BITFIELD8 urg:1;         /**< URG flag */
735    LT_BITFIELD8 ece:1;         /**< ECN Echo */
736    LT_BITFIELD8 cwr:1;         /**< ECN CWR */
737#  elif __BYTE_ORDER == __BIG_ENDIAN
738    LT_BITFIELD8 doff:4;        /**< Data offset */
739    LT_BITFIELD8 res1:3;        /**< Reserved bits */
740    LT_BITFIELD8 ecn_ns:1;      /**< ECN Nonce Sum */
741    LT_BITFIELD8 cwr:1;         /**< ECN CWR */
742    LT_BITFIELD8 ece:1;         /**< ECN Echo */
743    LT_BITFIELD8 urg:1;         /**< URG flag */
744    LT_BITFIELD8 ack:1;         /**< ACK flag */
745    LT_BITFIELD8 psh:1;         /**< PuSH flag */
746    LT_BITFIELD8 rst:1;         /**< RST flag */
747    LT_BITFIELD8 syn:1;         /**< SYN flag */
748    LT_BITFIELD8 fin:1;         /**< FIN flag */
749#  else
750#   error "Adjust your <bits/endian.h> defines"
751#  endif
752    uint16_t window;            /**< Window Size */
753    uint16_t check;             /**< Checksum */
754    uint16_t urg_ptr;           /**< Urgent Pointer */
755} PACKED libtrace_tcp_t;
756
757/** Generic UDP header structure */
758typedef struct libtrace_udp {
759  uint16_t      source;         /**< Source port */
760  uint16_t      dest;           /**< Destination port */
761  uint16_t      len;            /**< Length */
762  uint16_t      check;          /**< Checksum */
763} PACKED libtrace_udp_t;
764
765/** Generic ICMP header structure */
766typedef struct libtrace_icmp
767{
768  uint8_t type;         /**< Message Type */
769  uint8_t code;         /**< Type Sub-code */
770  uint16_t checksum;            /**< Checksum */
771  union
772  {
773    struct
774    {
775      uint16_t  id;             /**< ID of the Echo request */
776      uint16_t  sequence;       /**< Sequence number of the Echo request */
777    } echo;                     /**< Echo Datagram */
778    uint32_t    gateway;        /**< Gateway Address */
779    struct
780    {
781      uint16_t  unused;         /**< Unused */
782      uint16_t  mtu;            /**< Next-hop MTU */
783    } frag;                     /**< Path MTU Discovery */
784  } un;                         /**< Union for Payloads of Various ICMP Codes */
785} PACKED libtrace_icmp_t;
786
787/** Generic ICMPv6 header structure */
788typedef struct libtrace_icmp6 {
789  uint8_t type;         /**< Message Type */
790  uint8_t code;         /**< Type Sub-code */
791  uint16_t checksum;    /**< Checksum */
792
793  union {
794    struct {
795        uint8_t length;   /**< Length of original datagram content in 64 bit words */
796        uint8_t unused;   /**< Unused */       
797        uint8_t unused1;  /**< Unused */
798    } extend;   /**< Extensions added in RFC 4884 for Time Exceeded and Destination Unreachable Messages */
799
800    uint32_t mtu;       /**< MTU from Packet Too Big Message */
801    uint32_t pointer;   /**< Pointer from Parameter Problem Message */
802    struct {
803        uint16_t id;    /**< Echo Identifier */
804        uint16_t sequence; /**< Echo Sequence Number */
805    } echo; /**< Data required for Echo Request and Reply messages */
806  } un;
807} PACKED libtrace_icmp6_t;
808
809/** Generic LLC/SNAP header structure */
810typedef struct libtrace_llcsnap
811{
812/* LLC */
813  uint8_t dsap;                 /**< Destination Service Access Point */
814  uint8_t ssap;                 /**< Source Service Access Point */
815  uint8_t control;              /**< Control field */
816/* SNAP */
817  LT_BITFIELD32 oui:24;         /**< Organisationally Unique Identifier (scope)*/
818  uint16_t type;                /**< Protocol within OUI */
819} PACKED libtrace_llcsnap_t;
820
821/** 802.3 frame */
822typedef struct libtrace_ether
823{
824  uint8_t ether_dhost[6];       /**< Destination Ether Addr */
825  uint8_t ether_shost[6];       /**< Source Ether Addr */
826  uint16_t ether_type;          /**< Packet Type ID Field (next-header) */
827} PACKED libtrace_ether_t;
828
829/** 802.1Q frame */
830typedef struct libtrace_8021q
831{
832  LT_BITFIELD16 vlan_pri:3;      /**< VLAN User Priority */
833  LT_BITFIELD16 vlan_cfi:1;      /**< VLAN Format Indicator,
834                                   * 0 for ethernet, 1 for token ring */
835  LT_BITFIELD16 vlan_id:12;      /**< VLAN Id */
836  uint16_t vlan_ether_type;      /**< VLAN Sub-packet Type ID Field
837                                   * (next-header)*/
838} PACKED libtrace_8021q_t;
839
840/** ATM User Network Interface (UNI) Cell. */
841typedef struct libtrace_atm_cell
842{
843  LT_BITFIELD32 gfc:4;          /**< Generic Flow Control */
844  LT_BITFIELD32 vpi:8;          /**< Virtual Path Identifier */
845  LT_BITFIELD32 vci:16;         /**< Virtual Channel Identifier */
846  LT_BITFIELD32 pt:3;           /**< Payload Type */
847  LT_BITFIELD32 clp:1;          /**< Cell Loss Priority */
848  LT_BITFIELD32 hec:8;          /**< Header Error Control */
849} PACKED libtrace_atm_cell_t;
850
851/** ATM Network Node/Network Interface (NNI) Cell. */
852typedef struct libtrace_atm_nni_cell
853{
854  LT_BITFIELD32 vpi:12;         /**< Virtual Path Identifier */
855  LT_BITFIELD32 vci:16;         /**< Virtual Channel Identifier */
856  LT_BITFIELD32 pt:3;           /**< Payload Type */
857  LT_BITFIELD32 clp:1;          /**< Cell Loss Priority */
858  LT_BITFIELD32 hec:8;          /**< Header Error Control */
859} PACKED libtrace_atm_nni_cell_t;
860
861/** Captured UNI cell.
862 *
863 * Endace don't capture the HEC, presumably to keep alignment.  This
864 * version of the \ref libtrace_atm_cell is used when dealing with DAG
865 * captures of uni cells.
866 *
867 */
868typedef struct libtrace_atm_capture_cell
869{
870  LT_BITFIELD32 gfc:4;          /**< Generic Flow Control */
871  LT_BITFIELD32 vpi:8;          /**< Virtual Path Identifier */
872  LT_BITFIELD32 vci:16;         /**< Virtual Channel Identifier */
873  LT_BITFIELD32 pt:3;           /**< Payload Type */
874  LT_BITFIELD32 clp:1;          /**< Cell Loss Priority */
875} PACKED libtrace_atm_capture_cell_t;
876
877/** Captured NNI cell.
878 *
879 * Endace don't capture the HEC, presumably to keep alignment.  This
880 * version of the \ref libtrace_atm_nni_cell is used when dealing with DAG
881 * captures of nni cells.
882 *
883 */
884typedef struct libtrace_atm_nni_capture_cell
885{
886  LT_BITFIELD32 vpi:12;         /**< Virtual Path Identifier */
887  LT_BITFIELD32 vci:16;         /**< Virtual Channel Identifier */
888  LT_BITFIELD32 pt:3;           /**< Payload Type */
889  LT_BITFIELD32 clp:1;          /**< Cell Loss Priority */
890  LT_BITFIELD32 hec:8;          /**< Header Error Control */
891} PACKED libtrace_atm_nni_capture_cell_t;
892
893/** PPP header */
894typedef struct libtrace_ppp
895{
896 /* I can't figure out where the hell these two variables come from. They're
897  * definitely not in RFC 1661 which defines PPP. Probably some weird thing
898  * relating to the lack of distinction between PPP, HDLC and CHDLC */
899       
900/* uint8_t address; */          /**< PPP Address (0xFF - All stations) */
901/* uint8_t header;  */          /**< PPP Control (0x03 - Unnumbered info) */
902 uint16_t protocol;             /**< PPP Protocol (htons(0x0021) - IPv4 */
903} PACKED libtrace_ppp_t;
904
905/** PPPoE header */
906typedef struct libtrace_pppoe
907{
908 LT_BITFIELD8 version:4;        /**< Protocol version number */
909 LT_BITFIELD8 type:4;           /**< PPPoE Type */
910 uint8_t code;                  /**< PPPoE Code */
911 uint16_t session_id;           /**< Session Identifier */
912 uint16_t length;               /**< Total Length of the PPP packet */
913} PACKED libtrace_pppoe_t;
914
915/** Libtrace local definition of GRE (Generalised Routing Protocol) header
916 * RFC2890
917 */
918typedef struct libtrace_gre_t
919{
920    uint16_t flags;         /**< Flags and version */
921    uint16_t ethertype;     /**< Payload ethertype */
922    uint16_t checksum;      /**< Optional checksum */
923    uint16_t reserved1;     /**< Optional reserved */
924    uint16_t key;           /**< Optional key (or Tenant Network ID) */
925    uint16_t seq;           /**< Optional sequence number */
926} PACKED libtrace_gre_t;
927
928#define LIBTRACE_GRE_FLAG_CHECKSUM 0x8000
929#define LIBTRACE_GRE_FLAG_KEY      0x2000
930#define LIBTRACE_GRE_FLAG_SEQ      0x1000
931#define LIBTRACE_GRE_FLAG_VERMASK  0x0007
932
933
934/* PPTP GRE (RFC2637) */
935#define LIBTRACE_GRE_FLAG_ACK      0x0080
936#define LIBTRACE_GRE_PPTP_VERSION  0x0001
937
938/** Libtrace local definition of VXLAN Header
939 * (draft-mahalingam-dutt-dcops-vxlan)
940 */
941typedef struct libtrace_vxlan_t
942{
943    uint8_t flags;          /**< Flags */
944    uint8_t reserved1[3];   /**< Reserved */
945    uint8_t vni[3];         /**< VXLAN Network Identifier (VNI) */
946    uint8_t reserved2;
947} PACKED libtrace_vxlan_t;
948
949/** 802.11 header */
950typedef struct libtrace_80211_t {
951#if __BYTE_ORDER == __LITTLE_ENDIAN
952        LT_BITFIELD32      protocol:2;  /**< Protocol Version */
953        LT_BITFIELD32      type:2;      /**< Frame Type */
954        LT_BITFIELD32      subtype:4;   /**< Frame Subtype */
955#else
956        LT_BITFIELD32      subtype:4;   /**< Frame Subtype */
957        LT_BITFIELD32      type:2;      /**< Frame Type */
958        LT_BITFIELD32      protocol:2;  /**< Protocol Version */
959#endif
960
961#if __BYTE_ORDER == __LITTLE_ENDIAN
962        LT_BITFIELD32      to_ds:1;     /**< Packet to Distribution Service */
963        LT_BITFIELD32      from_ds:1;   /**< Packet from Distribution Service */
964        LT_BITFIELD32      more_frag:1; /**< Packet has more fragments */
965        LT_BITFIELD32      retry:1;     /**< Packet is a retry */
966        LT_BITFIELD32      power:1;     /**< Power Management mode */
967        LT_BITFIELD32      more_data:1; /**< More data is buffered at station */
968        LT_BITFIELD32      wep:1;       /**< WEP encryption indicator */
969        LT_BITFIELD32      order:1;     /**< Strictly-Ordered class indicator */
970#else
971        LT_BITFIELD32      order:1;     /**< Strictly-Ordered class indicator */
972        LT_BITFIELD32      wep:1;       /**< WEP encryption indicator */
973        LT_BITFIELD32      more_data:1; /**< More data is buffered at station */
974        LT_BITFIELD32      power:1;     /**< Power Management mode */
975        LT_BITFIELD32      retry:1;     /**< Packet is a retry */
976        LT_BITFIELD32      more_frag:1; /**< Packet has more fragments */
977        LT_BITFIELD32      from_ds:1;   /**< Packet from Distribution Service */
978        LT_BITFIELD32      to_ds:1;     /**< Packet to Distribution Service */
979#endif
980       
981        uint16_t     duration;  /**< Duration value for NAV calculation */
982        uint8_t      mac1[6];   /**< MAC Address 1 */
983        uint8_t      mac2[6];   /**< MAC Address 2 */
984        uint8_t      mac3[6];   /**< MAC Address 3 */
985        uint16_t     SeqCtl;    /**< Sequence Control */       
986        uint8_t      mac4[6];   /**< MAC Address 4 */
987} PACKED libtrace_80211_t;
988
989/** The Radiotap header pre-amble
990 *
991 * All Radiotap headers start with this pre-amble, followed by the fields
992 * specified in the it_present bitmask. If bit 31 of it_present is set, then
993 * another bitmask follows.
994 * @note All of the radiotap data fields are in little-endian byte-order.
995 */
996typedef struct libtrace_radiotap_t {
997    uint8_t     it_version; /**< Radiotap version */
998    uint8_t     it_pad; /**< Padding for natural alignment */
999    uint16_t    it_len; /**< Length in bytes of the entire Radiotap header */
1000    uint32_t    it_present; /**< Which Radiotap fields are present */
1001} PACKED libtrace_radiotap_t;
1002
1003/** OSPF header */
1004typedef struct libtrace_ospf_v2_t
1005{
1006        uint8_t ospf_v;         /**< OSPF Version, should be 2 */
1007        uint8_t type;           /**< OSPF Packet Type */
1008        uint16_t ospf_len;      /**< Packet length, including OSPF header */
1009        struct in_addr router;  /**< Router ID of the packet source */
1010        struct in_addr area;    /**< Area the packet belongs to */
1011        uint16_t sum;           /**< Checksum */
1012        uint16_t au_type;       /**< Authentication procedure */
1013        uint16_t zero;          /**< Always zero */
1014        uint8_t au_key_id;      /**< Authentication Key ID */
1015        uint8_t au_data_len;    /**< Authentication Data Length */
1016        uint32_t au_seq_num;    /**< Cryptographic Sequence Number */
1017} PACKED libtrace_ospf_v2_t;
1018
1019/** Options Field present in some OSPFv2 packets */
1020typedef struct libtrace_ospf_options_t {
1021#if __BYTE_ORDER == __LITTLE_ENDIAN
1022        LT_BITFIELD8 unused1:1;
1023        LT_BITFIELD8 e_bit:1;
1024        LT_BITFIELD8 mc_bit:1;
1025        LT_BITFIELD8 np_bit:1;
1026        LT_BITFIELD8 ea_bit:1;
1027        LT_BITFIELD8 dc_bit:1;
1028        LT_BITFIELD8 unused2:2;
1029#elif __BYTE_ORDER == __BIG_ENDIAN
1030        LT_BITFIELD8 unused2:2;
1031        LT_BITFIELD8 dc_bit:1;
1032        LT_BITFIELD8 ea_bit:1;
1033        LT_BITFIELD8 np_bit:1;
1034        LT_BITFIELD8 mc_bit:1;
1035        LT_BITFIELD8 e_bit:1;
1036        LT_BITFIELD8 unused1:1;
1037#endif
1038} PACKED libtrace_ospf_options_t;
1039
1040/** LSA Header for OSPFv2 */
1041typedef struct libtrace_ospf_lsa_v2_t
1042{
1043        uint16_t age;           /**< Time in seconds since LSA originated */
1044        libtrace_ospf_options_t lsa_options;    /**< Options */
1045        uint8_t lsa_type;       /**< LSA type */
1046        struct in_addr ls_id;   /**< Link State ID */
1047        struct in_addr adv_router; /**< Router that originated this LSA */
1048        uint32_t seq;           /**< LS sequence number */
1049        uint16_t checksum;      /**< Checksum */
1050        uint16_t length;        /**< Length of the LSA including LSA header */
1051} PACKED libtrace_ospf_lsa_v2_t;
1052
1053/** OSPFv2 Hello Packet */
1054typedef struct libtrace_ospf_hello_v2_t
1055{
1056        struct in_addr mask;    /**< Network mask for this interface */
1057        uint16_t interval;      /**< Interval between Hello packets (secs) */
1058        libtrace_ospf_options_t hello_options;  /**< Options */
1059        uint8_t priority;       /**< Router Priority */
1060        uint32_t deadint;       /**< Interval before declaring a router down */
1061        struct in_addr designated;      /**< Designated router for the network */
1062        struct in_addr backup;  /**< Backup designated router */
1063
1064        /** Neighbors follow from here, but there can be anywhere from 1 to N
1065         * neighbors so I can't include that here */
1066} PACKED libtrace_ospf_hello_v2_t;
1067
1068/** OSPFv2 Database Description packet */
1069typedef struct libtrace_ospf_db_desc_v2_t
1070{
1071        uint16_t mtu;           /**< Interface MTU */
1072        libtrace_ospf_options_t db_desc_options;        /**< Options */
1073#if __BYTE_ORDER == __LITTLE_ENDIAN
1074        LT_BITFIELD8 db_desc_ms:1;      /**< If set, this router is the master */
1075        LT_BITFIELD8 db_desc_m:1;       /**< If set, more packets to follow */
1076        LT_BITFIELD8 db_desc_i:1;       /**< If set, this is the first packet in sequence */
1077        LT_BITFIELD8 zero:5;
1078#elif __BYTE_ORDER == __BIG_ENDIAN
1079        LT_BITFIELD8 zero:5;
1080        LT_BITFIELD8 db_desc_i:1;       /**< If set, this is the first packet in sequence */
1081        LT_BITFIELD8 db_desc_m:1;       /**< If set, more packets to follow */
1082        LT_BITFIELD8 db_desc_ms:1;      /**< If set, this router is the master */
1083#endif
1084        uint32_t seq;           /**< Sequence number for DD packets */
1085} PACKED libtrace_ospf_db_desc_v2_t;
1086
1087/** OSPF Link State Request Packet */
1088typedef struct libtrace_ospf_ls_req_t
1089{
1090        uint32_t ls_type;       /**< Link State Type */
1091        uint32_t ls_id;         /**< Link State Id */
1092        uint32_t advertising_router;    /**< Advertising Router */
1093} PACKED libtrace_ospf_ls_req_t;
1094
1095/** OSPF Link State Update Packet */
1096typedef struct libtrace_ospf_ls_update_t
1097{
1098        uint32_t ls_num_adv;    /**< Number of LSAs in this packet */
1099
1100        /* Followed by LSAs, use API functions to access these */
1101} PACKED libtrace_ospf_ls_update_t;
1102
1103/** OSPFv2 AS External LSA Body */
1104typedef struct libtrace_ospf_as_external_lsa_t
1105{
1106        struct in_addr netmask; /**< Netmask for the destination */
1107#if __BYTE_ORDER == __LITTLE_ENDIAN
1108        LT_BITFIELD8 tos:7;
1109        LT_BITFIELD8 e:1;       /**< If set, metric is Type 2. Else, Type 1 */
1110#elif __BYTE_ORDER == __BIG_ENDIAN
1111        LT_BITFIELD8 e:1;       /**< If set, metric is Type 2. Else, Type 1 */
1112        LT_BITFIELD8 tos:7;
1113#endif
1114        uint8_t metric_a;       /**< Byte 1 of the Metric field */
1115        uint8_t metric_b;       /**< Byte 2 of the Metric field */
1116        uint8_t metric_c;       /**< Byte 3 of the Metric field */
1117        struct in_addr forwarding;      /**< Forwarding address */
1118        uint32_t external_tag;          /**< External Route Tag */
1119} PACKED libtrace_ospf_as_external_lsa_v2_t;
1120
1121/** OSPFv2 Summary LSA Body */
1122typedef struct libtrace_ospf_summary_lsa
1123{
1124        struct in_addr netmask; /**< Netmask for the destination */
1125        uint8_t zero;           /**< Always zero */
1126        uint8_t metric_a;       /**< Byte 1 of the Metric field */
1127        uint8_t metric_b;       /**< Byte 2 of the Metric field */
1128        uint8_t metric_c;       /**< Byte 3 of the Metric field */
1129       
1130} PACKED libtrace_ospf_summary_lsa_v2_t;
1131
1132/** OSPFv2 Network LSA Body */
1133typedef struct libtrace_ospf_network_lsa_t
1134{
1135        struct in_addr netmask; /**< Netmask for the network */
1136        /* Followed by IDs of attached routers */
1137} PACKED libtrace_ospf_network_lsa_v2_t;
1138
1139/** OSPFv2 Router Link structure */
1140typedef struct libtrace_ospf_link_t
1141{
1142        struct in_addr link_id;         /**< Object that link connects to */
1143        struct in_addr link_data;       /**< Link Data field */
1144        uint8_t type;                   /**< Link Type */
1145        uint8_t num_tos;                /**< Number of TOS metrics */
1146        uint16_t tos_metric;            /**< Cost of router link */
1147} PACKED libtrace_ospf_link_v2_t;
1148
1149/** OSPFv2 Router LSA */
1150typedef struct libtrace_ospf_router_lsa_t
1151{
1152#if __BYTE_ORDER == __LITTLE_ENDIAN
1153        LT_BITFIELD8 b:1;       /**< Area Border Router Flag */
1154        LT_BITFIELD8 e:1;       /**< External Router Flag */
1155        LT_BITFIELD8 v:1;       /**< Virtual Endpoint Flag */
1156        LT_BITFIELD8 zero:5;
1157#elif __BYTE_ORDER == __BIG_ENDIAN
1158        LT_BITFIELD8 zero:5;
1159        LT_BITFIELD8 v:1;       /**< Virtual Endpoint Flag */
1160        LT_BITFIELD8 e:1;       /**< External Router Flag */
1161        LT_BITFIELD8 b:1;       /**< Area Border Router Flag */
1162#endif
1163        uint8_t zero2;          /**< Always zero */
1164        uint16_t num_links;     /**< Number of links in LSA */
1165} PACKED libtrace_ospf_router_lsa_v2_t;
1166
1167/** OSPF message types */
1168typedef enum {
1169        TRACE_OSPF_HELLO = 1,           /**< OSPF Hello */
1170        TRACE_OSPF_DATADESC = 2,        /**< OSPF Database Description */
1171        TRACE_OSPF_LSREQ = 3,           /**< OSPF Link State Request */
1172        TRACE_OSPF_LSUPDATE = 4,        /**< OSPF Link State Update */
1173        TRACE_OSPF_LSACK = 5            /**< OSPF Link State Acknowledgement */
1174} libtrace_ospf_types_t;
1175
1176/** OSPF link state acknowledgement types */
1177typedef enum {
1178        TRACE_OSPF_LS_ROUTER = 1,       /**< OSPF Router LSA */
1179        TRACE_OSPF_LS_NETWORK = 2,      /**< OSPF Network LSA */
1180        TRACE_OSPF_LS_SUMMARY = 3,      /**< OSPF Summary LSA */
1181        TRACE_OSPF_LS_ASBR_SUMMARY = 4, /**< OSPF Summary LSA (ASBR) */
1182        TRACE_OSPF_LS_EXTERNAL = 5      /**< OSPF AS External LSA */
1183} libtrace_ospf_ls_types_t;
1184
1185/** A local definition of an SLL header */
1186typedef struct libtrace_sll_header_t {
1187        uint16_t pkttype;               /**< Packet type */
1188        uint16_t hatype;                /**< Link-layer address type */
1189        uint16_t halen;                 /**< Link-layer address length */
1190        unsigned char addr[8];          /**< Link-layer address */
1191        uint16_t protocol;              /**< Protocol */
1192} libtrace_sll_header_t;
1193
1194
1195/* SLL packet types */
1196
1197/** Packet was addressed for the local host */
1198#define TRACE_SLL_HOST          0
1199/** Packet was addressed for a broadcast address */
1200#define TRACE_SLL_BROADCAST     1
1201/** Packet was addressed for a multicast address */
1202#define TRACE_SLL_MULTICAST     2
1203/** Packet was addressed for another host but was captured by a promiscuous
1204 * device */
1205#define TRACE_SLL_OTHERHOST     3
1206/** Packet originated from the local host */
1207#define TRACE_SLL_OUTGOING      4
1208
1209
1210#ifdef WIN32
1211#pragma pack(pop)
1212#endif
1213
1214
1215/*@}*/
1216
1217/** Prints help information for libtrace
1218 *
1219 * Function prints out some basic help information regarding libtrace,
1220 * and then prints out the help() function registered with each input module
1221 */
1222DLLEXPORT void trace_help(void);
1223
1224/** Causes a libtrace reader to stop blocking whilst waiting on new packets
1225 * and immediately return EOF.
1226 *
1227 * This function is useful if you are handling signals within your libtrace
1228 * program. If a live source is not receiving any packets (or they are being
1229 * filtered), a call to trace_read_packet will result in an infinite loop as
1230 * it will block until a packet is received. Normally, a SIGINT would cause the
1231 * program to end and thus break the loop, but if you are handling the signal
1232 * yourself then that signal will never reach libtrace.
1233 *
1234 * Instead this function sets a global variable within libtrace that will
1235 * cause a blocking live capture to break on the next internal timeout,
1236 * allowing control to be returned to the user and their own signal handling
1237 * to kick in.
1238 */
1239DLLEXPORT void trace_interrupt(void);
1240
1241/** @name Trace management
1242 * These members deal with creating, configuring, starting, pausing and
1243 * cleaning up a trace object
1244 *@{
1245 */
1246
1247/** Takes a uri and splits it into a format and uridata component.
1248 * @param uri           The uri to be parsed
1249 * @param [out] format  A pointer that will be updated to point to an allocated
1250 *                      string holding the format component of the URI
1251 * @return NULL if an error occurred, otherwise return a pointer to the uridata
1252 * component
1253 *
1254 * @note The format component is strdup'd by this function, so be sure to free
1255 * it when you are done with the split URI. Similarly, do not pass a pointer
1256 * to an allocated string into this function as the 'format' parameter, as
1257 * that memory will be leaked and replaced with the strdup'd format.
1258 */
1259DLLEXPORT const char *trace_parse_uri(const char *uri, char **format);
1260
1261/** Create an input trace from a URI
1262 *
1263 * @param uri A valid libtrace URI to be opened
1264 * @return An opaque pointer to a libtrace_t
1265 *
1266 * Some valid URI's are:
1267 *  - erf:/path/to/erf/file
1268 *  - erf:-  (stdin)
1269 *  - dag:/dev/dagcard
1270 *  - pcapint:pcapinterface                (eg: pcap:eth0)
1271 *  - pcap:/path/to/pcap/file
1272 *  - pcap:-
1273 *  - rt:hostname
1274 *  - rt:hostname:port
1275 *
1276 *  If an error occurred when attempting to open the trace file, a
1277 *  trace is still returned so trace_is_err() should be called to find out
1278 *  if an error occurred. The trace is created in the configuration state, you
1279 *  must call trace_start before attempting to read packets from the trace.
1280 */
1281DLLEXPORT libtrace_t *trace_create(const char *uri);
1282
1283/** Creates a "dummy" trace file that has only the format type set.
1284 *
1285 * @param uri A valid (but fake) URI indicating the format of the dummy trace that is to be created.
1286 * @return An opaque pointer to a (sparsely initialised) libtrace_t
1287 *
1288 * Only the format portion of the uri parameter matters - the 'file' being
1289 * opened does not have to exist.
1290 *
1291 * @note IMPORTANT: Do not attempt to call trace_read_packet or other such
1292 * functions with the dummy trace. Its intended purpose is to provide access
1293 * to the format functions where the original trace may no longer exist or is
1294 * not the correct format, e.g. reading ERF packets from an RT input.
1295 */
1296DLLEXPORT libtrace_t *trace_create_dead(const char *uri);
1297
1298/** Creates a trace output file from a URI.
1299 *
1300 * @param uri The uri string describing the output format and destination
1301 * @return An opaque pointer to a libtrace_output_t
1302 *
1303 * Valid URIs include:
1304 *  - erf:/path/to/erf/file
1305 *  - pcap:/path/to/pcap/file
1306 *
1307 *  If an error occurred when attempting to open the output trace, a trace is
1308 *  still returned but trace_errno will be set. Use trace_is_err_out() and
1309 *  trace_perror_output() to get more information.
1310 */
1311DLLEXPORT libtrace_out_t *trace_create_output(const char *uri);
1312
1313/** Start an input trace
1314 * @param libtrace      The trace to start
1315 * @return 0 on success, -1 on failure
1316 *
1317 * This does the actual work of starting the input trace and applying
1318 * all the config options.  This may fail, returning -1. The libtrace error
1319 * handling functions can be used to get more information about what
1320 * specifically went wrong.
1321 */
1322DLLEXPORT int trace_start(libtrace_t *libtrace);
1323
1324/** Pauses an input trace
1325 * @param libtrace      The trace to pause
1326 * @return 0 on success, -1 on failure
1327 *
1328 * This stops an input trace that is in progress and returns you to the
1329 * configuration state.  Any packets that arrive on a live capture after
1330 * trace_pause() has been called will be discarded.  To resume the trace, call
1331 * trace_start().
1332 */
1333DLLEXPORT int trace_pause(libtrace_t *libtrace);
1334
1335/** Start an output trace
1336 * @param libtrace      The trace to start
1337 * @return 0 on success, -1 on failure
1338 *
1339 * This does the actual work with starting a trace capable of writing packets. 
1340 * This generally creates the output file.
1341 */
1342DLLEXPORT int trace_start_output(libtrace_out_t *libtrace);
1343
1344/** Valid configuration options for input traces */
1345typedef enum {
1346        /** Maximum number of bytes to be captured for any given packet */
1347        TRACE_OPTION_SNAPLEN,   
1348
1349        /** If enabled, places a live capture interface into promiscuous mode */
1350        TRACE_OPTION_PROMISC,   
1351
1352        /** Apply this filter to all packets read from this trace */
1353        TRACE_OPTION_FILTER,   
1354
1355        /** Defines the frequency of meta-data reporting, e.g. DUCK packets */
1356        TRACE_OPTION_META_FREQ,
1357
1358        /** If enabled, the libtrace event API will ignore time gaps between
1359         * packets when reading from a trace file */
1360        TRACE_OPTION_EVENT_REALTIME,
1361
1362        /** The hasher function for a parallel libtrace. It is recommended to
1363         * access this option via trace_set_hasher(). */
1364        TRACE_OPTION_HASHER,
1365
1366        /** Speed up trace file replays (via trace_event()) by this factor */
1367        TRACE_OPTION_REPLAY_SPEEDUP,
1368} trace_option_t;
1369
1370/** Sets an input config option
1371 * @param libtrace      The trace object to apply the option to
1372 * @param option        The option to set
1373 * @param value         The value to set the option to
1374 * @return -1 if option configuration failed, 0 otherwise
1375 *
1376 * This should be called after trace_create(), and before trace_start()
1377 *
1378 * @note Please consider using the newer trace_set_X() functions to access
1379 * this function.
1380 */
1381DLLEXPORT int trace_config(libtrace_t *libtrace,
1382                trace_option_t option,
1383                void *value);
1384
1385/** Maximum number of bytes to be captured for any given packet
1386 *
1387 * @param libtrace The trace object to apply the option to
1388 * @param snaplen The snap length to set
1389 * @return -1 if option configuration failed, 0 otherwise
1390 */
1391DLLEXPORT int trace_set_snaplen(libtrace_t *trace, int snaplen);
1392
1393/** If enabled, places a live capture interface into promiscuous mode
1394 *
1395 * @param libtrace The trace object to apply the option to
1396 * @param promisc
1397 * @return -1 if option configuration failed, 0 otherwise
1398 */
1399DLLEXPORT int trace_set_promisc(libtrace_t *trace, bool promisc);
1400
1401/** Apply this filter to all packets read from this trace
1402 *
1403 * @param libtrace The trace object to apply the option to
1404 * @param filter The filter to apply
1405 * @return -1 if option configuration failed, 0 otherwise
1406 */
1407DLLEXPORT int trace_set_filter(libtrace_t *trace, libtrace_filter_t *filter);
1408
1409/** Defines the frequency of meta-data reporting, e.g. DUCK packets
1410 *
1411 * @param libtrace The trace object to apply the option to
1412 * @param freq The meta data frequency
1413 * @return -1 if option configuration failed, 0 otherwise
1414 */
1415DLLEXPORT int trace_set_meta_freq(libtrace_t *trace, int freq);
1416
1417/** If enabled, the libtrace event API will ignore time gaps between
1418 * packets when reading from a trace file.
1419 *
1420 * @param libtrace The trace object to apply the option to
1421 * @param realtime True ignores gaps
1422 * @return -1 if option configuration failed, 0 otherwise
1423 */
1424DLLEXPORT int trace_set_event_realtime(libtrace_t *trace, bool realtime);
1425
1426/** Valid compression types
1427 * Note, this must be kept in sync with WANDIO_COMPRESS_* numbers in wandio.h
1428 */
1429typedef enum {
1430        TRACE_OPTION_COMPRESSTYPE_NONE = 0, /**< No compression */
1431        TRACE_OPTION_COMPRESSTYPE_ZLIB = 1, /**< GZip Compression */
1432        TRACE_OPTION_COMPRESSTYPE_BZ2  = 2, /**< BZip2 Compression */
1433        TRACE_OPTION_COMPRESSTYPE_LZO  = 3,  /**< LZO Compression */
1434        TRACE_OPTION_COMPRESSTYPE_LZMA  = 4,  /**< LZO Compression */
1435        TRACE_OPTION_COMPRESSTYPE_LAST
1436} trace_option_compresstype_t;
1437
1438/** Valid configuration options for output traces */
1439typedef enum {
1440        /** File flags to use when opening an output file, e.g. O_APPEND */
1441        TRACE_OPTION_OUTPUT_FILEFLAGS,
1442        /** Compression level: 0 = no compression, 1 = faster compression,
1443         * 9 = better compression */
1444        TRACE_OPTION_OUTPUT_COMPRESS,
1445        /** Compression type, see trace_option_compresstype_t */
1446        TRACE_OPTION_OUTPUT_COMPRESSTYPE
1447} trace_option_output_t;
1448
1449/* To add a new stat field update this list, and the relevant places in
1450 * libtrace_stat_t structure.
1451 */
1452/** An X Macro set for libtrace stat fields */
1453#define LIBTRACE_STAT_FIELDS \
1454        X(accepted) \
1455        X(filtered) \
1456        X(received) \
1457        X(dropped) \
1458        X(captured) \
1459        X(missing) \
1460        X(errors)
1461
1462/**
1463 * Statistic counters are cumulative from the time the trace is started.
1464 * Trace pause will reset the counters, to zero.
1465 * Always check \a{field}_valid is set before attempting to read the stored
1466 * value.
1467 *
1468 * @note Always allocate this structure using trace_create_statistics().
1469 *       This allows us to extend the structure in the future.
1470 */
1471typedef struct libtrace_stat_t {
1472#define X(name) LT_BITFIELD64 name ##_valid : 1;
1473        LIBTRACE_STAT_FIELDS
1474#undef X
1475        /* We use the remaining space as magic to ensure the structure
1476         * was alloc'd by us. We can easily decrease the no. bits without
1477         * problems as long as we update any asserts as needed */
1478        LT_BITFIELD64 reserved1: 25; /**< Bits reserved for future fields */
1479        LT_BITFIELD64 reserved2: 24; /**< Bits reserved for future fields */
1480        LT_BITFIELD64 magic: 8; /**< A number stored against the format to
1481                                  ensure the struct was allocated correctly */
1482
1483        /* These must all be uint64_t's, match this order with the X macro */
1484        /** The number of packets that have been read from the input trace
1485         * using trace_read_packet(). In the parallel framework this may include
1486         * some packets waiting in a batch yet to be seen by the user's
1487         * application.
1488         *
1489         * This does not include filtered packets because these do not make it
1490         * to trace_read_packet().
1491         *
1492         * @note This field replaces trace_get_accepted_packets()
1493         */
1494        uint64_t accepted;
1495
1496        /** The number of packets that were captured, but discarded for not
1497         * matching a provided filter.
1498         *
1499         * @note This field replaces trace_get_filtered_packets()
1500         */
1501        uint64_t filtered;
1502
1503        /** The total number of good packets which have been received. Including
1504         * those which are dropped and filtered. This does not include errors.
1505         *
1506         * @note This may include a small number of buffered packets
1507         *       not yet included in accepted.
1508         *
1509         * @note This field replaces trace_get_received_packets()
1510         */
1511        uint64_t received;
1512
1513        /** The number of packets that have been dropped on an input trace
1514         * due to lack of buffer space on the capturing device. This does not
1515         * included errored packets which are dropped directly by the card.
1516         *
1517         * @note This field replaces trace_get_dropped_packets()
1518         */
1519        uint64_t dropped;
1520
1521        /** The number of received packets that have not been dropped. This
1522         * includes filtered packets.
1523         *
1524         * This is equivalent to received-dropped.
1525         *
1526         * @note This may include a small number of buffered packets
1527         *       not yet included in accepted.
1528         */
1529        uint64_t captured;
1530
1531        /** The number of packets (or aggregated records) that have been
1532         *  lost between the original capture device and the current input
1533         *  trace.
1534         *
1535         *  @note Only relevant for input formats that use a network to
1536         *  transfer live captured packets from one host to another (e.g.
1537         *  nDAG).
1538         */
1539        uint64_t missing;
1540
1541        /** The number of packets that have been discarded by the network card
1542         * because they are invalid. That includes FCS mismatches, incorrect
1543         * packet lengths etc.
1544         */
1545        uint64_t errors;
1546} libtrace_stat_t;
1547
1548ct_assert(offsetof(libtrace_stat_t, accepted) == 8);
1549
1550/** Sets an output config option
1551 *
1552 * @param libtrace      The output trace object to apply the option to
1553 * @param option        The option to set
1554 * @param value         The value to set the option to
1555 * @return -1 if option configuration failed, 0 otherwise
1556 * This should be called after trace_create_output, and before
1557 * trace_start_output
1558 */
1559DLLEXPORT int trace_config_output(libtrace_out_t *libtrace,
1560                trace_option_output_t option,
1561                void *value
1562                );
1563
1564/** Close an input trace, freeing up any resources it may have been using
1565 *
1566 * @param trace         The input trace to be destroyed
1567 *
1568 */
1569DLLEXPORT void trace_destroy(libtrace_t *trace);
1570
1571/** Close a dummy trace file, freeing up any resources it may have been using
1572 * @param trace         The dummy trace to be destroyed
1573 */
1574DLLEXPORT void trace_destroy_dead(libtrace_t *trace);
1575
1576/** Close an output trace, freeing up any resources it may have been using
1577 * @param trace         The output trace to be destroyed
1578 */
1579DLLEXPORT void trace_destroy_output(libtrace_out_t *trace);
1580
1581/** Flush an output trace, forcing any buffered packets to be written
1582 * @param libtrace      The output trace to be flushed
1583 */
1584DLLEXPORT int trace_flush_output(libtrace_out_t *libtrace);
1585
1586/** Check (and clear) the current error state of an input trace
1587 * @param trace         The input trace to check the error state on
1588 * @return The current error status and message
1589 *
1590 * This reads and returns the current error state and sets the current error
1591 * to "no error".
1592 */
1593DLLEXPORT libtrace_err_t trace_get_err(libtrace_t *trace);
1594
1595/** Indicate if there has been an error on an input trace
1596 * @param trace         The input trace to check the error state on
1597 * @return true if an error has occurred, false otherwise
1598 *
1599 * @note This does not clear the error status, and only returns true or false.
1600 */
1601DLLEXPORT bool trace_is_err(libtrace_t *trace);
1602
1603/** Outputs the error message for an input trace to stderr and clear the error
1604 * status.
1605 * @param trace         The input trace with the error to output
1606 * @param msg           The message to prepend to the error
1607 *
1608 * This function does clear the error status.
1609 */
1610DLLEXPORT void trace_perror(libtrace_t *trace, const char *msg,...) PRINTF(2,3);
1611
1612/** Checks (and clears) the current error state for an output trace
1613 * @param trace         The output trace to check the error state on
1614 * @return The current error status and message
1615 *
1616 * This reads and returns the current error state and sets the current error
1617 * to "no error".
1618 */
1619DLLEXPORT libtrace_err_t trace_get_err_output(libtrace_out_t *trace);
1620
1621/** Indicates if there is an error on an output trace
1622 * @param trace         The output trace to check the error state on
1623 * @return true if an error has occurred, false otherwise.
1624 *
1625 * This does not clear the error status, and only returns true or false.
1626 */
1627DLLEXPORT bool trace_is_err_output(libtrace_out_t *trace);
1628
1629/** Outputs the error message for an output trace to stderr and clear the error
1630 * status.
1631 * @param trace         The output trace with the error to output
1632 * @param msg           The message to prepend to the error
1633 * This function does clear the error status.
1634 */
1635DLLEXPORT void trace_perror_output(libtrace_out_t *trace, const char *msg,...)
1636        PRINTF(2,3);
1637
1638/** Returns the number of packets observed on an input trace.
1639 * Includes the number of packets counted as early as possible, before
1640 * filtering, and includes dropped packets.
1641 *
1642 * @param trace         The input trace to examine
1643 * @returns The number of packets seen at the capture point before filtering.
1644 *
1645 * If the number is not known, this function will return UINT64_MAX
1646 *
1647 * @deprecated This function is deprecated: Use trace_get_statistics(), this
1648 *             allows all statistic counters to be read in an atomic manner.
1649 */
1650DLLEXPORT DEPRECATED
1651uint64_t trace_get_received_packets(libtrace_t *trace);
1652
1653/** Returns the number of packets that were captured, but discarded for not
1654 * matching a provided filter.
1655 *
1656 * @param trace         The input trace to examine
1657 * @returns The number of packets that were successfully captured, but filtered
1658 *
1659 * If the number is not known, this function will return UINT64_MAX
1660 *
1661 * @deprecated This function is deprecated: Use trace_get_statistics(), this
1662 *             allows all statistic counters to be read in an atomic manner.
1663 */
1664DLLEXPORT DEPRECATED
1665uint64_t trace_get_filtered_packets(libtrace_t *trace);
1666
1667/** Returns the number of packets that have been dropped on an input trace due
1668 * to lack of buffer space on the capturing device.
1669 *
1670 * @param trace         The input trace to examine
1671 * @returns The number of packets captured, but dropped due to buffer overruns
1672 *
1673 * If the number is not known, this function will return UINT64_MAX
1674 *
1675 * @deprecated This function is deprecated: Use trace_get_statistics(), this
1676 *             allows all statistic counters to be read in an atomic manner.
1677 */
1678DLLEXPORT DEPRECATED
1679uint64_t trace_get_dropped_packets(libtrace_t *trace);
1680
1681/** Returns the number of packets that have been read from the input trace using
1682 * trace_read_packet().
1683 *
1684 * @param trace         The input trace to examine
1685 * @returns The number of packets that have been read by the libtrace user.
1686 *
1687 * If the number is not known, this function will return UINT64_MAX
1688 *
1689 * @deprecated This function is deprecated: Use trace_get_statistics(), this
1690 *             allows all statistic counters to be read in an atomic manner.
1691 */
1692DLLEXPORT DEPRECATED
1693uint64_t trace_get_accepted_packets(libtrace_t *trace);
1694
1695/**
1696 * Returns statistic counters for a trace, for a parallel trace this is a
1697 * combined total.
1698 * Where possible these are retrieved atomically, however this behaviour depends
1699 * on the underlying trace format.
1700 *
1701 * @param trace The input trace to examine.
1702 * @param stats Optional, Filled upon return with statistics about the trace,
1703 *              check the flags included to see if a given statistic is valid.
1704 *              If NULL a statistic structure owned by libtrace is returned, this
1705 *              should not be free'd and will become invalid if the trace is
1706 *              destroyed.
1707 *
1708 * @return A pointer to the statistics structure.
1709 * @note Use trace_create_stat() to create the stats object, this way future
1710 *       versions of libtrace can add to the structure without breaking existing
1711 *       code.
1712 */
1713DLLEXPORT
1714libtrace_stat_t *trace_get_statistics(libtrace_t *trace, libtrace_stat_t *stats);
1715
1716
1717/**
1718 * Returns statistic counters for a single thread of a trace.
1719 * Where possible these are retrieved atomically, however this behaviour depends
1720 * on the underlying trace format.
1721 *
1722 * @param trace The input trace to examine.
1723 * @param t An optional thread to received stats for or NULL to retrieve stats
1724 *          for the current thread
1725 * @param stats Filled upon return with statistics about the trace, check the
1726 *              flags included to see if a given statistic is valid.
1727 *
1728 * @note Use trace_create_stat() to create the stats object, this way future
1729 *       versions of libtrace can add to the structure without breaking existing
1730 *       code.
1731 */
1732DLLEXPORT
1733void trace_get_thread_statistics(libtrace_t *trace, libtrace_thread_t *t,
1734                                 libtrace_stat_t *stats);
1735
1736/**
1737 * Creates and returns a zeroed libtrace_stat_t structure.
1738 *
1739 * This allows us to add extra fields increasing the size of the structure
1740 * without breaking existing libtrace applications.
1741 *
1742 * This structure should be free'd using free().
1743 *
1744 * @return A valid pointer to a libtrace_stat_t struct otherwise NULL if
1745 *         memory was not available.
1746 */
1747DLLEXPORT libtrace_stat_t* trace_create_statistics(void);
1748
1749/**
1750 * Clear all fields of given statistic.
1751 * This api doesn't verify the magic field unlike other stat apis.
1752 *
1753 * @param s The statistic structure to clear
1754 */
1755DLLEXPORT
1756void trace_clear_statistics(libtrace_stat_t *s);
1757
1758/**
1759 * Performs the operation c=a-b accounting for valid fields.
1760 * c is allowed to be a or b.
1761 *
1762 * @param a The minuend
1763 * @param b The subtrahend
1764 * @param c The resulting difference
1765 */
1766DLLEXPORT
1767void trace_subtract_statistics(const libtrace_stat_t *a,
1768                               const libtrace_stat_t *b, libtrace_stat_t *c);
1769
1770/**
1771 * Performs operation c=a+b accounting for valid fields.
1772 * c is allowed to be a or b.
1773 *
1774 * @param a The first operand
1775 * @param b The second operand
1776 * @param c The result
1777 */
1778DLLEXPORT
1779void trace_add_statistics(const libtrace_stat_t *a,
1780                          const libtrace_stat_t *b, libtrace_stat_t *c);
1781
1782/**
1783 * Prints all valid stats to a file stream, (which could be stdout/err).
1784 * By default the format "name: value" is used.
1785 *
1786 * @param s The statistic structure to print
1787 * @param f The output file stream
1788 * @param format An optional format string such as the default ("%s: %"PRIu64"\n")
1789 *               This is passed to fprintf and called with two arguments
1790 *               first a char* (%s) and second a uint64_t (%PRIu64).
1791 *
1792 * @return -1 if an error occurs when writing to the file stream, check errno.
1793 *         Otherwise 0.
1794 */
1795DLLEXPORT
1796int trace_print_statistics(const libtrace_stat_t *s, FILE *f,
1797                           const char *format);
1798
1799
1800/*@}*/
1801
1802/** @name Reading / Writing packets
1803 * These members deal with creating, reading and writing packets
1804 *
1805 * @{
1806 */
1807
1808/** Create a new packet object
1809 *
1810 * @return A pointer to an initialised libtrace_packet_t object, or NULL if
1811 * libtrace is unable to allocate space for a new packet.
1812 */
1813DLLEXPORT libtrace_packet_t *trace_create_packet(void);
1814
1815/** Copy a packet object
1816 * @param packet        The source packet to copy
1817 * @return A new packet which has the same content as the source packet
1818 *
1819 * @note This always involves a copy, which can be slow.  Use of this
1820 * function should be avoided where possible.
1821 *
1822 * @par The reason you would want to use this function is that a zero-copied
1823 * packet from a device will be stored using memory owned by the device which
1824 * may be a limited resource. Copying the packet will ensure that the packet
1825 * is now stored in memory owned and managed by libtrace.
1826 */
1827DLLEXPORT libtrace_packet_t *trace_copy_packet(const libtrace_packet_t *packet);
1828
1829/** Destroy a packet object
1830 * @param packet        The packet to be destroyed
1831 *
1832 */
1833DLLEXPORT void trace_destroy_packet(libtrace_packet_t *packet);
1834
1835/** Read the next packet from an input trace
1836 *
1837 * @param trace         The libtrace opaque pointer for the input trace
1838 * @param packet        The packet opaque pointer
1839 * @return 0 on EOF, negative value on error, number of bytes read when successful.
1840 *
1841 * @note The number of bytes read is usually (but not always) the same as
1842 * trace_get_framing_length()+trace_get_capture_length() depending on the
1843 * trace format.
1844 *
1845 * @note The trace must have been started with trace_start before calling
1846 * this function
1847 *
1848 * @note When reading from a live capture, this function will block until a
1849 * packet is observed on the capture interface. The libtrace event API
1850 * (e.g. trace_event()) should be used if non-blocking operation is required.
1851 */
1852DLLEXPORT int trace_read_packet(libtrace_t *trace, libtrace_packet_t *packet);
1853
1854/** Converts the data provided in buffer into a valid libtrace packet
1855 *
1856 * @param trace         An input trace of the same format as the "packet"
1857 *                      contained in the buffer
1858 * @param packet        The libtrace packet to prepare
1859 * @param buffer        A buffer containing the packet data, including the
1860 *                      capture format header
1861 * @param rt_type       The RT type for the packet that is being prepared
1862 * @param flags         Used to specify options for the preparation function,
1863 *                      e.g. who owns the packet buffer
1864 *
1865 * @return -1 if an error occurs, 0 otherwise
1866 *
1867 * Packet preparation is a tricky concept - the idea is to take the data
1868 * pointed to by 'buffer' and treat it as a packet record of the same capture
1869 * format as that used by the input trace. The provided libtrace packet then
1870 * has its internal pointers and values set to describe the packet record in
1871 * the buffer.
1872 *
1873 * The primary use of this function is to allow the RT packet reader to
1874 * easily and safely convert packets from the RT format back into the format
1875 * that they were originally captured with., essentially removing the RT
1876 * encapsulation.
1877 *
1878 * This function is now available via the exported API, as it can have some
1879 * uses outside of internal libtrace contexts. However, we strongly advise
1880 * that you avoid using this function unless you really know what you are
1881 * doing.
1882 */
1883DLLEXPORT int trace_prepare_packet(libtrace_t *trace, libtrace_packet_t *packet,
1884                void *buffer, libtrace_rt_types_t rt_type, uint32_t flags);
1885
1886/** Flags for prepare_packet functions */
1887enum {
1888        /** The buffer memory has been allocated by libtrace and should be
1889         * freed when the packet is destroyed. */
1890        TRACE_PREP_OWN_BUFFER           =1,
1891
1892        /** The buffer memory is externally-owned and must not be freed by
1893         * libtrace when the packet is destroyed. */
1894        TRACE_PREP_DO_NOT_OWN_BUFFER    =0
1895};
1896
1897
1898/** Event types
1899 * see \ref libtrace_eventobj_t and \ref trace_event
1900 */
1901typedef enum {
1902        TRACE_EVENT_IOWAIT,     /**< Wait on the given file descriptor */
1903        TRACE_EVENT_SLEEP,      /**< Sleep for the given amount of time */
1904        TRACE_EVENT_PACKET,     /**< Packet has been read from input trace */
1905        TRACE_EVENT_TERMINATE   /**< End of input trace */
1906} libtrace_event_t;
1907
1908/** Structure returned by libtrace_event explaining what the current event is */
1909typedef struct libtrace_eventobj_t {
1910        libtrace_event_t type; /**< Event type (iowait,sleep,packet) */
1911       
1912        /** If the event is IOWAIT, the file descriptor to wait on */
1913        int fd;               
1914        /** If the event is SLEEP, the amount of time to sleep for in seconds */
1915        double seconds;       
1916        /** If the event is PACKET, the value returned by trace_read_packet() */
1917        int size;
1918} libtrace_eventobj_t;
1919
1920/** Processes the next libtrace event from an input trace.
1921 * @param trace The libtrace opaque pointer for the input trace
1922 * @param packet The libtrace_packet opaque pointer to use for reading packets
1923 * @return A libtrace_event struct containing the event type and details of the event.
1924 *
1925 * Type can be:
1926 *  TRACE_EVENT_IOWAIT  Waiting on I/O on a file descriptor
1927 *  TRACE_EVENT_SLEEP   Wait a specified amount of time for the next event
1928 *  TRACE_EVENT_PACKET  Packet was read from the trace
1929 *  TRACE_EVENT_TERMINATE Trace terminated (perhaps with an error condition)
1930 */
1931DLLEXPORT libtrace_eventobj_t trace_event(libtrace_t *trace,
1932                libtrace_packet_t *packet);
1933
1934
1935/** Write one packet out to the output trace
1936 *
1937 * @param trace         The libtrace_out opaque pointer for the output trace
1938 * @param packet        The packet opaque pointer of the packet to be written
1939 * @return The number of bytes written out, if zero or negative then an error has occured.
1940 */
1941DLLEXPORT int trace_write_packet(libtrace_out_t *trace, libtrace_packet_t *packet);
1942
1943/** Gets the capture format for a given packet.
1944 * @param packet        The packet to get the capture format for.
1945 * @return The capture format of the packet
1946 *
1947 * @note Due to ability to convert packets between formats relatively easily
1948 * in Libtrace, the format of the packet right now may not be the format that
1949 * the packet was originally captured with.
1950 */
1951DLLEXPORT
1952enum base_format_t trace_get_format(struct libtrace_packet_t *packet);
1953
1954/** Construct a libtrace packet from a buffer containing the packet payload.
1955 * @param[in,out] packet        Libtrace Packet object to update with the new
1956 *                              data.
1957 * @param linktype              The linktype of the packet data.
1958 * @param[in] data              The packet data (including linklayer).
1959 * @param len                   Length of packet data provided in the buffer.
1960 *
1961 * @note The constructed packet will be in the PCAP format.
1962 *
1963 * @note To be useful, the provided buffer must start with the layer 2 header
1964 * (or a metadata header, if desired).
1965 */
1966DLLEXPORT
1967void trace_construct_packet(libtrace_packet_t *packet,
1968                libtrace_linktype_t linktype, const void *data, uint16_t len);
1969
1970/*@}*/
1971
1972/** @name Protocol decodes
1973 * These functions locate and return a pointer to various headers inside a
1974 * packet
1975 *
1976 * A packet is divided up into several "layers.":
1977 *
1978 * @li Framing header -- This is the header provided by the capture format
1979 * itself rather than anything that was sent over the network. This provides
1980 * basic details about the packet record including capture lengths, wire
1981 * lengths, timestamps, direction information and any other metadata that is
1982 * part of the capture format. 
1983 *
1984 * @li Metadata header (optional) -- A header containing metadata about a
1985 * packet that was captured, but the metadata was not transmitted over the
1986 * wire.  Some examples include RadioTap and Linux_sll headers.  This can be
1987 * retrieved by trace_get_packet_meta(), or skipped using
1988 * trace_get_payload_from_meta(). There may be multiple "metadata" headers on
1989 * a packet.
1990 *
1991 * @li Layer 2/Link layer/Datalink header -- This can be retrieved by
1992 * trace_get_layer2(), or skipped using trace_get_payload_from_layer2().
1993 *
1994 * @li Layer 3/IP/IPv6 -- This can be retrieved by trace_get_layer3().  As a
1995 * convenience trace_get_ip()/trace_get_ip6() can be used to find an IPv4/IPv6
1996 * header.
1997 *
1998 * @li Layer 5/transport -- These are protocols carried in IPv4/IPv6 frames.
1999 * These can be retrieved using trace_get_transport().
2000 *
2001 * @{
2002 */
2003
2004
2005/** Gets a pointer to the first byte of the packet as it was captured and
2006 * returns its corresponding linktype and capture length.
2007 *
2008 * Use this function instead of the deprecated trace_get_link().
2009 *
2010 * @param packet The packet to get the buffer from
2011 * @param[out] linktype The linktype of the returned pointer
2012 * @param[out] remaining The capture length (the number of captured bytes from
2013 * the returned pointer)
2014 * @return A pointer to the first byte of the packet
2015 */
2016DLLEXPORT void *trace_get_packet_buffer(const libtrace_packet_t *packet,
2017                libtrace_linktype_t *linktype, uint32_t *remaining);
2018
2019/** Get a pointer to the link layer for a given packet
2020 * @param packet        The packet to get the link layer for
2021 *
2022 * @return A pointer to the link layer, or NULL if there is no link layer
2023 *
2024 * @deprecated This function is deprecated: Use trace_get_packet_buffer() or
2025 * one of the trace_get_layer*() functions instead.
2026 * @note You should call trace_get_link_type to find out what type of link
2027 * layer has been returned to you.
2028 */
2029DLLEXPORT SIMPLE_FUNCTION DEPRECATED
2030void *trace_get_link(const libtrace_packet_t *packet);
2031
2032/** Strips layer 2.5 headers from a given packet.
2033 * @param packet        The packet to strip headers from.
2034 *
2035 * @return The packet with the requested headers removed (if they were
2036 * present).
2037 *
2038 * This function is intended for removing those pesky layer 2.5 headers
2039 * that are not supported by other packet analysis applications, e.g. VLAN
2040 * and MPLS headers. If successful, the resulting packet will be a simple
2041 * Ethernet-IP-Transport packet that just about anything should be able to
2042 * parse without difficulty.
2043 *
2044 * If this function encounters a layer 2 or 2.5 header that it does not
2045 * support, stripping will cease and the packet returning will be stripped
2046 * up to but not including the unsupported header.
2047 *
2048 * New in libtrace 4.0.0
2049 *
2050 * @note This function only supports stripping headers from Ethernet packets
2051 * for now. Passing in packets of other link types will simply result in
2052 * the original packet being returned unmodified.
2053 *
2054 */
2055DLLEXPORT libtrace_packet_t *trace_strip_packet(libtrace_packet_t *packet);
2056
2057/** Get a pointer to the IPv4 header (if any) for a given packet
2058 * @param packet        The packet to get the IPv4 header for
2059 *
2060 * @return A pointer to the IPv4 header, or NULL if there is no IPv4 header
2061 *
2062 * If a partial IP header is present, i.e. the packet has been truncated before
2063 * the end of the IP header, this function will return NULL.
2064 *
2065 * You should consider using \ref trace_get_layer3 instead of this function.
2066 */
2067DLLEXPORT SIMPLE_FUNCTION
2068libtrace_ip_t *trace_get_ip(libtrace_packet_t *packet);
2069
2070/** get a pointer to the IPv6 header (if any)
2071 * @param packet        The packet to get the IPv6 header for
2072 *
2073 * @return A pointer to the IPv6 header, or NULL if there is no IPv6 header
2074 *
2075 * If a partial IPv6 header is present, i.e. the packet has been truncated
2076 * before the end of the IP header, this function will return NULL.
2077 *
2078 * You should consider using \ref trace_get_layer3 instead of this function.
2079 */
2080DLLEXPORT SIMPLE_FUNCTION
2081libtrace_ip6_t *trace_get_ip6(libtrace_packet_t *packet);
2082
2083/** Return a pointer to the first metadata header in a packet, if present.
2084 *
2085 * This function takes a pointer to a libtrace packet and if any metadata
2086 * headers exist, returns a pointer to the first one, along with its
2087 * corresponding linktype.
2088 *
2089 * If no metadata headers exist in the packet, NULL is returned.
2090 *
2091 * A metadata header is a header that was prepended by the capturing device,
2092 * such as a Linux SLL header, or a Radiotap wireless monitoring header.
2093 * Subsequent metadata headers may be accessed with the
2094 * trace_get_payload_from_meta(...) function.
2095 *
2096 * @param packet The libtrace packet
2097 * @param[out] linktype The linktype of the returned metadata header
2098 * @param[out] remaining The number of bytes captured after the returned
2099 * pointer.
2100 * @return A pointer to the first metadata header, or NULL if there are no
2101 * metadata headers present.
2102 *
2103 * remaining may be NULL, however linktype must be provided.
2104 */
2105DLLEXPORT void *trace_get_packet_meta(const libtrace_packet_t *packet,
2106                libtrace_linktype_t *linktype,
2107                uint32_t *remaining);
2108
2109/** Returns the payload of a metadata header.
2110 *
2111 * This function takes a pointer to the start of a metadata header (either
2112 * obtained via trace_get_packet_meta(...) or by a previous call to
2113 * trace_get_payload_from_meta(...)) along with its corresponding linktype and
2114 * returns the payload, i.e. the next header. It will also update the linktype
2115 * parameter to indicate the type of payload.
2116 * 
2117 * If the linktype indicates that the header passed in is not a metadata
2118 * header, the function returns NULL to indicate this. The linktype remains
2119 * unchanged in this case.
2120 *
2121 * This function allows the user to iterate through metadata headers which are
2122 * sometimes present before the actual packet as it was received on the wire.
2123 * Examples of metadata headers include the Linux SLL header and the Radiotap
2124 * wireless monitoring header.
2125 *
2126 * If the metadata header passed into this function is truncated, this
2127 * function will return NULL, and remaining will be set to 0.
2128 *
2129 * If there are 0 bytes of payload following the provided metadata header, the
2130 * function will return a pointer to where the header would otherwise be and
2131 * remaining will be 0.
2132 *
2133 * Therefore, be sure to check the value of remaining after calling this
2134 * function!
2135 *
2136 * @param[in] meta A pointer to a metadata header
2137 * @param[in,out] linktype The linktype of meta (updated to indicate the
2138 * linktype of the returned header if applicable).
2139 * @param[in,out] remaining The number of bytes after the meta pointer.
2140 * @return A pointer to the payload of the metadata header. If meta is not a
2141 * pointer to a metadata header, NULL is returned and linktype remains
2142 * unchanged.
2143 *
2144 * All parameters are mandatory.
2145 */
2146DLLEXPORT void *trace_get_payload_from_meta(const void *meta,
2147                libtrace_linktype_t *linktype,
2148                uint32_t *remaining);
2149
2150
2151/** Get a pointer to the layer 2 header. Generally this is the first byte of the
2152 * packet as it was seen on the wire.
2153 *
2154 * This function takes a libtrace packet and skips over any metadata headers if
2155 * present (such as Linux SLL or Radiotap) and returns a pointer to the first
2156 * byte of the packet that was actually received by the network interface.
2157 *
2158 * @param packet The libtrace packet to find the layer 2 header for
2159 * @param[out] linktype The linktype of the returned layer 2 header
2160 * @param[out] remaining The number of bytes left in the packet after the
2161 * returned pointer.
2162 * @return A pointer to the first byte of the packet as it was seen on the
2163 * wire. If no layer 2 header is present, this function will return NULL.
2164 *
2165 * remaining may be NULL, otherwise it will be filled in by the function.
2166 */
2167DLLEXPORT void *trace_get_layer2(const libtrace_packet_t *packet,
2168                libtrace_linktype_t *linktype,
2169                uint32_t *remaining);
2170
2171/** Gets a pointer to the next header following a layer 2 header
2172 *
2173 * @param l2                    The pointer to the current layer 2 header
2174 * @param linktype              The type of the layer 2 header
2175 * @param[out] ethertype        An optional output variable of the ethernet type of the new header
2176 * @param[in,out] remaining     Updated with the number of captured bytes
2177                                remaining
2178 *
2179 * @return A pointer to the header following the provided layer 2 header, or
2180 * NULL if no subsequent header is present.
2181 *
2182 * Remaining must point to the number of bytes captured from the layer 2 header
2183 * and beyond.  It will be decremented by the number of bytes skipped to find
2184 * the payload.
2185 *
2186 * If the layer 2 header is complete but there are zero bytes of payload after
2187 * the end of the header, a pointer to where the payload would be is returned
2188 * and remaining will be set to 0.  If the layer 2 header is incomplete
2189 * (truncated), then NULL is returned and remaining will be set to 0.
2190 * Therefore, it is very important to check the value of remaining after
2191 * calling this function.
2192 *
2193 */
2194DLLEXPORT void *trace_get_payload_from_layer2(void *l2,
2195                libtrace_linktype_t linktype,
2196                uint16_t *ethertype,
2197                uint32_t *remaining);
2198
2199
2200/** Get a pointer to the layer 3 (e.g. IP) header.
2201 * @param packet  The libtrace packet to find the layer 3 header for
2202 * @param[out] ethertype The ethertype of the layer 3 header
2203 * @param[out] remaining The amount of captured data remaining in the packet starting from the returned pointer, i.e. including the layer 3 header.
2204 *
2205 * @return A pointer to the layer 3 header. If no layer 3 header is present in
2206 * the packet, NULL is returned. If the layer 3 header is truncated, a valid
2207 * pointer will still be returned so be sure to check the value of remaining
2208 * before attempting to process the returned header.
2209 *
2210 * remaining may be NULL, otherwise it will be set to the number of captured
2211 * bytes after the pointer returned.
2212 */
2213DLLEXPORT
2214void *trace_get_layer3(const libtrace_packet_t *packet,
2215                uint16_t *ethertype, uint32_t *remaining);
2216
2217/** Calculates the expected IP checksum for a packet.
2218 * @param packet        The libtrace packet to calculate the checksum for
2219 * @param[out] csum     The checksum that is calculated by this function. This
2220 *                      may not be NULL.
2221 *
2222 * @return A pointer to the original checksum field within the IP
2223 * header. If the checksum field is not present in the packet, NULL is returned.
2224 *
2225 * @note The return value points to the checksum that exists within the current
2226 * packet. The value in csum is the value that the checksum should be, given
2227 * the current packet contents. 
2228 *
2229 * @note This function involves the use of a memcpy, so be careful about
2230 * calling it excessively if performance is a concern for you.
2231 *
2232 * New in libtrace 3.0.17
2233 */
2234DLLEXPORT uint16_t *trace_checksum_layer3(libtrace_packet_t *packet,
2235                uint16_t *csum);
2236
2237/** Calculates the expected checksum for the transport header in a packet.
2238 * @param packet        The libtrace packet to calculate the checksum for
2239 * @param[out] csum     The checksum that is calculated by this function. This
2240 *                      may not be NULL.
2241 *
2242 * @return A pointer to the original checksum field within the transport
2243 * header. If the checksum field is not present in the packet, NULL is returned.
2244 *
2245 * @note The return value points to the checksum that exists within the current
2246 * packet. The value in csum is the value that the checksum should be, given
2247 * the current packet contents. 
2248 *
2249 * @note This function involves the use of a memcpy, so be careful about
2250 * calling it excessively if performance is a concern for you.
2251 *
2252 * @note Because transport checksums are calculated across the entire payload,
2253 * truncated packets will result in NULL being returned.
2254 *
2255 * This function will determine the appropriate checksum for whatever transport
2256 * layer header is present in the provided packet. At this stage, this only
2257 * currently works for TCP, UDP and ICMP packets.
2258 *
2259 * Be wary of TCP checksum offloading if you are examining the checksum of
2260 * packets captured on the same host that generated them!
2261 *
2262 * New in libtrace 3.0.17
2263 */
2264DLLEXPORT uint16_t *trace_checksum_transport(libtrace_packet_t *packet,
2265                uint16_t *csum);
2266
2267/** Calculates the fragment offset in bytes for an IP packet
2268 * @param packet        The libtrace packet to calculate the offset for
2269 * @param[out] more     A boolean flag to indicate whether there are more
2270 *                      fragments after the current packet.
2271 * @return The fragment offset for the packet in bytes. If the packet is not
2272 * an IP packet or the fragment offset is not present in packet, the return
2273 * value will be 0.
2274 *
2275 * @note The value returned is in bytes, not 8-octet units as it is stored
2276 * in the fragment offset field in the headers. In other words, libtrace
2277 * automatically does the multiplication for you.
2278 *
2279 * The value passed in for 'more' does not matter; it will be overwritten
2280 * with the value of the More Fragments flag from the IP header.
2281 *
2282 * New in libtrace 3.0.20
2283 */
2284DLLEXPORT uint16_t trace_get_fragment_offset(const libtrace_packet_t *packet,
2285                uint8_t *more);
2286
2287/** Gets a pointer to the transport layer header (if any)
2288 * @param packet   The libtrace packet to find the transport header for
2289 * @param[out] proto    The protocol present at the transport layer.
2290 * @param[out] remaining The amount of captured data remaining in the packet
2291 * starting from the returned pointer, i.e. including the transport header.
2292 *
2293 * @return A pointer to the transport layer header. If no transport header is
2294 * present in the packet, NULL is returned. If the transport header is
2295 * truncated, a valid pointer will still be returned so be sure to check the
2296 * value of remaining before attempting to process the returned header.
2297 *
2298 * remaining may be NULL, otherwise it will be set to the number of captured
2299 * bytes after the returned pointer.
2300 *
2301 * @note proto may be NULL if proto is unneeded.
2302 */
2303DLLEXPORT void *trace_get_transport(const libtrace_packet_t *packet,
2304                uint8_t *proto, uint32_t *remaining);
2305
2306/** Gets a pointer to the payload following an IPv4 header
2307 * @param ip            The IPv4 Header
2308 * @param[out] proto    The protocol of the header following the IPv4 header
2309 * @param[in,out] remaining Updated with the number of captured bytes remaining
2310 *
2311 * @return A pointer to the transport layer header, or NULL if no subsequent
2312 * header is present.
2313 *
2314 * When calling this function, remaining must contain the number of captured
2315 * bytes remaining in the packet starting from the IPv4 header (including the
2316 * IPv4 header itself).
2317 *
2318 * remaining will be decremented by the size of the IPv4 header (including any
2319 * options). If the IPv4 header is complete but there are zero bytes of payload
2320 * after the IPv4 header, a pointer to where the payload would be is returned
2321 * and remaining will be set to 0.  If the IPv4 header is incomplete, NULL will
2322 * be returned and remaining will be set to 0. Therefore, it is very important
2323 * to check the value of remaining after calling this function.
2324 *
2325 * proto may be NULL, in which case it won't be updated.
2326 *
2327 * @note This is similar to trace_get_transport_from_ip in libtrace2
2328 */
2329DLLEXPORT void *trace_get_payload_from_ip(libtrace_ip_t *ip, uint8_t *proto,
2330                uint32_t *remaining);
2331
2332/** Gets a pointer to the payload following an IPv6 header
2333 * @param ipptr         The IPv6 Header
2334 * @param[out] proto    The protocol of the header following the IPv6 header
2335 * @param[in,out] remaining Updated with the number of captured bytes remaining
2336 *
2337 * @return A pointer to the transport layer header, or NULL if no subsequent
2338 * header is present.
2339 *
2340 * When calling this function, remaining must contain the number of captured
2341 * bytes remaining in the packet starting from the IPv6 header (including the
2342 * IPv6 header itself).
2343 *
2344 * remaining will be decremented by the size of the IPv6 header (including any
2345 * options). If the IPv6 header is complete but there are zero bytes of payload
2346 * after the IPv6 header, a pointer to where the payload would be is returned
2347 * and remaining will be set to 0.  If the IPv6 header is incomplete, NULL will
2348 * be returned and remaining will be set to 0. Therefore, it is very important
2349 * to check the value of remaining after calling this function.
2350 *
2351 * proto may be NULL, in which case it won't be updated.
2352 *
2353 */
2354DLLEXPORT void *trace_get_payload_from_ip6(libtrace_ip6_t *ipptr,
2355                uint8_t *proto, uint32_t *remaining);
2356
2357/** Gets a pointer to the payload following a link header
2358 * @param linkptr       A pointer to the link layer header
2359 * @param linktype      The linktype of the link header being examined
2360 * @param[out] type     An output variable for the ethernet type
2361 * @param[in,out] remaining Updated with the number of captured bytes remaining
2362 *
2363 * @return A pointer to the header following the link header, or NULL if no
2364 * subsequent header is present.
2365 *
2366 * When calling this function, remaining must contain the number of captured
2367 * bytes remaining in the packet starting from the link header (including the
2368 * link header itself). remaining will be updated to contain the number of
2369 * bytes remaining after the link header has been skipped.
2370 *
2371 * @deprecated This function is deprecated: you should be using
2372 * trace_get_payload_from_layer2() or trace_get_payload_from_meta() instead.
2373 *
2374 */
2375DLLEXPORT void *trace_get_payload_from_link(void *linkptr,
2376                libtrace_linktype_t linktype,
2377                uint16_t *type, uint32_t *remaining);
2378
2379/** Gets a pointer to the payload following an 802.1q (VLAN) header.
2380 * @param vlan      A pointer to the VLAN header
2381 * @param[out] type  The ethernet type, replaced with the VLAN ether type
2382 * @param[in,out] remaining Updated with the number of captured bytes remaining
2383 *
2384 * @return A pointer to the header beyond the VLAN header, if one is present.
2385 * Otherwise, returns NULL. 
2386 *
2387 * When calling this function, remaining must contain the number of captured
2388 * bytes remaining in the packet starting from the VLAN header (including the
2389 * VLAN header itself). remaining will be updated to contain the number of
2390 * bytes remaining after the VLAN header has been skipped.
2391 *
2392 * If the VLAN header is complete but there are zero bytes of payload after
2393 * the VLAN header, a pointer to where the payload would be is returned and
2394 * remaining will be set to 0.  If the VLAN header is incomplete, NULL will be
2395 * returned and remaining will be set to 0. Therefore, it is important to check
2396 * the value of remaining after calling this function.
2397 *
2398 * type will be set to the ethertype of the VLAN payload. This parameter is not
2399 * mandatory, but is highly recommended.
2400 *
2401 */
2402DLLEXPORT void *trace_get_payload_from_vlan(
2403                void *vlan, uint16_t *type, uint32_t *remaining);
2404
2405/** Gets a pointer to the payload following an MPLS header.
2406 * @param mpls      A pointer to the MPLS header
2407 * @param[out] type  The ethernet type, replaced by the ether type of the
2408 * returned header - 0x0000 if an Ethernet header is returned
2409 * @param[in,out] remaining Updated with the number of captured bytes remaining
2410 *
2411 * @return A pointer to the header beyond the MPLS label, if one is present.
2412 * Will return NULL if there is not enough bytes remaining to skip past the
2413 * MPLS label.
2414 *
2415 * When calling this function, remaining must contain the number of captured
2416 * bytes remaining in the packet starting from the MPLS header (including the
2417 * MPLS header itself). remaining will be updated to contain the number of
2418 * bytes remaining after the MPLS header has been skipped.
2419 *
2420 * If the MPLS header is complete but there are zero bytes of payload after
2421 * the MPLS header, a pointer to where the payload would be is returned and
2422 * remaining will be set to 0.  If the MPLS header is incomplete, NULL will be
2423 * returned and remaining will be set to 0. Therefore, it is important to check
2424 * the value of remaining after calling this function.
2425 *
2426 * type will be set to the ethertype of the MPLS payload. This parameter is
2427 * mandatory - it may not be NULL.
2428 *
2429 * @note This function will only remove one MPLS label at a time - the type
2430 * will be set to 0x8847 if there is another MPLS label following the one
2431 * skipped by this function.
2432 *
2433 */
2434DLLEXPORT void *trace_get_payload_from_mpls(
2435                void *mpls, uint16_t *type, uint32_t *remaining);
2436
2437/** Gets a pointer to the payload following a PPPoE header
2438 * @param pppoe      A pointer to the PPPoE header
2439 * @param[out] type  The ethernet type, replaced by the ether type of the
2440 * returned header - 0x0000 if an Ethernet header is returned
2441 * @param[in,out] remaining  Updated with the number of captured bytes remaining
2442 *
2443 * @return A pointer to the header beyond the PPPoE header. NOTE that this
2444 * function will also skip over the PPP header that will immediately follow
2445 * the PPPoE header. This function will return NULL if there are not enough
2446 * bytes remaining to skip past both the PPPoE and PPP headers.
2447 *
2448 * When calling this function, remaining must contain the number of captured
2449 * bytes remaining in the packet starting from the PPPoE header (including the
2450 * PPPoE header itself). remaining will be updated to contain the number of
2451 * bytes remaining after the PPPoE and PPP headers have been removed.
2452 *
2453 * If the PPPoE and PPP headers are complete but there are zero bytes of
2454 * payload after the PPP header, a pointer to where the payload would be is
2455 * returned and remaining will be set to 0.  If the PPPoE or PPP header is
2456 * incomplete, NULL will be returned and remaining will be set to 0. Therefore,
2457 * it is important to check the value of remaining after calling this function.
2458 *
2459 * type will be set to the ether type of the PPP payload. This parameter is
2460 * mandatory - it may not be NULL.
2461 *
2462 */
2463DLLEXPORT void *trace_get_payload_from_pppoe(
2464                void *pppoe, uint16_t *type, uint32_t *remaining);
2465
2466/** Gets a pointer to the payload following a TCP header
2467 * @param tcp           A pointer to the TCP header
2468 * @param[in,out] remaining Updated with the number of captured bytes remaining
2469 *
2470 * @return A pointer to the TCP payload, or NULL if the TCP header is truncated.
2471 *
2472 * When calling this function, remaining must contain the number of captured
2473 * bytes remaining in the packet starting from the TCP header (including the
2474 * TCP header itself). remaining will be updated to contain the number of
2475 * bytes remaining after the TCP header has been skipped.
2476 *
2477 * If the TCP header is complete but there are zero bytes of payload after
2478 * the TCP header, a pointer to where the payload would be is returned and
2479 * remaining will be set to 0.  If the TCP header is incomplete, NULL will be
2480 * returned and remaining will be set to 0. Therefore, it is important to check
2481 * the value of remaining after calling this function.
2482 *
2483 */
2484DLLEXPORT void *trace_get_payload_from_tcp(libtrace_tcp_t *tcp,
2485                uint32_t *remaining);
2486
2487/** Gets a pointer to the payload following a UDP header
2488 * @param udp           A pointer to the UDP header
2489 * @param[in,out] remaining Updated with the number of captured bytes remaining
2490 *
2491 * @return A pointer to the UDP payload, or NULL if the UDP header is truncated.
2492 *
2493 * When calling this function, remaining must contain the number of captured
2494 * bytes remaining in the packet starting from the UDP header (including the
2495 * UDP header itself). remaining will be updated to contain the number of
2496 * bytes remaining after the UDP header has been skipped.
2497 *
2498 * If the UDP header is complete but there are zero bytes of payload after
2499 * the UDP header, a pointer to where the payload would be is returned and
2500 * remaining will be set to 0.  If the UDP header is incomplete, NULL will be
2501 * returned and remaining will be set to 0. Therefore, it is important to check
2502 * the value of remaining after calling this function.
2503 *
2504 */
2505DLLEXPORT void *trace_get_payload_from_udp(libtrace_udp_t *udp, uint32_t *remaining);
2506
2507/** Gets a pointer to the payload following a ICMP header
2508 * @param icmp           A pointer to the ICMP header
2509 * @param[in,out] remaining Updated with the number of captured bytes remaining
2510 *
2511 * @return A pointer to the ICMP payload, or NULL if the ICMP header is
2512 * truncated.
2513 *
2514 * When calling this function, remaining must contain the number of captured
2515 * bytes remaining in the packet starting from the ICMP header (including the
2516 * ICMP header itself). remaining will be updated to contain the number of
2517 * bytes remaining after the ICMP header has been skipped.
2518 *
2519 * If the ICMP header is complete but there are zero bytes of payload after
2520 * the ICMP header, a pointer to where the payload would be is returned and
2521 * remaining will be set to 0.  If the ICMP header is incomplete, NULL will be
2522 * returned and remaining will be set to 0. Therefore, it is important to check
2523 * the value of remaining after calling this function.
2524 *
2525 * @note In the case of some ICMP messages, the payload may be the IP header
2526 * from the packet that triggered the ICMP message.
2527 *
2528 */
2529DLLEXPORT void *trace_get_payload_from_icmp(libtrace_icmp_t *icmp,
2530                uint32_t *remaining);
2531
2532/** Gets a pointer to the payload following a ICMPv6 header
2533 * @param icmp           A pointer to the ICMPv6 header
2534 * @param[in,out] remaining Updated with the number of captured bytes remaining
2535 *
2536 * @return A pointer to the ICMPv6 payload, or NULL if the ICMPv6 header is
2537 * truncated.
2538 *
2539 * When calling this function, remaining must contain the number of captured
2540 * bytes remaining in the packet starting from the ICMPv6 header (including the
2541 * ICMP header itself). remaining will be updated to contain the number of
2542 * bytes remaining after the ICMPv6 header has been skipped.
2543 *
2544 * If the ICMPv6 header is complete but there are zero bytes of payload after
2545 * the header, a pointer to where the payload would be is returned and
2546 * remaining will be set to 0.  If the ICMPv6 header is incomplete, NULL will be
2547 * returned and remaining will be set to 0. Therefore, it is important to check
2548 * the value of remaining after calling this function.
2549 *
2550 * @note In the case of some ICMPv6 messages, the payload may be the IP header
2551 * from the packet that triggered the ICMP message.
2552 *
2553 */
2554DLLEXPORT void *trace_get_payload_from_icmp6(libtrace_icmp6_t *icmp,
2555                uint32_t *remaining);
2556
2557/** Gets a pointer to the payload following a GRE header
2558 * @param         gre       A pointer to the beginning of the GRE header.
2559 * @param[in,out] remaining Updated with the number of captured bytes remaining.
2560 *
2561 * @return A pointer to the GRE payload, or NULL if the GRE header is truncated.
2562 *
2563 * When calling this function, remaining must contain the number of captured
2564 * bytes remaining in the packet starting from the GRE header (including the
2565 * GRE header itself). remaining will be updated to contain the number of
2566 * bytes remaining after the GRE header has been skipped.
2567 *
2568 * If the GRE header is complete but there are zero bytes of payload after
2569 * the header, a pointer to where the payload would be is returned and
2570 * remaining will be set to 0.  If the GRE header is incomplete, NULL will be
2571 * returned and remaining will be set to 0. Therefore, it is important to check
2572 * the value of remaining after calling this function.
2573 */
2574DLLEXPORT void *trace_get_payload_from_gre(libtrace_gre_t *gre,
2575                uint32_t *remaining);
2576
2577/** Gets a pointer to the payload following a VXLAN header
2578 * @param         udp       A pointer to the beginning of the UDP header.
2579 * @param[in,out] remaining Updated with the number of captured bytes remaining.
2580 *
2581 * @return A pointer to the beginning of the VXLAN header, or NULL if the UDP
2582 * header is truncated, or this is not a VXLAN packet.
2583 *
2584 */
2585DLLEXPORT libtrace_vxlan_t *trace_get_vxlan_from_udp(libtrace_udp_t *udp,
2586                uint32_t *remaining);
2587
2588/** Gets a pointer to the payload following a VXLAN header
2589 * @param         vxlan       A pointer to the beginning of the VXLAN header.
2590 * @param[in,out] remaining Updated with the number of captured bytes remaining.
2591 *
2592 * @return A pointer to the VXLAN payload, or NULL if the VXLAN header is
2593 * truncated.
2594 *
2595 * When calling this function, remaining must contain the number of captured
2596 * bytes remaining in the packet starting from the VXLAN header (including the
2597 * VXLAN header itself). remaining will be updated to contain the number of
2598 * bytes remaining after the VXLAN header has been skipped.
2599 *
2600 * If the VXLAN header is complete but there are zero bytes of payload after
2601 * the header, a pointer to where the payload would be is returned and
2602 * remaining will be set to 0.  If the VXLAN header is incomplete, NULL will be
2603 * returned and remaining will be set to 0. Therefore, it is important to check
2604 * the value of remaining after calling this function.
2605 */
2606DLLEXPORT void *trace_get_payload_from_vxlan(libtrace_vxlan_t *vxlan,
2607                uint32_t *remaining);
2608
2609/** Get a pointer to the TCP header (if present)
2610 * @param packet        The packet to get the TCP header from
2611 *
2612 * @return A pointer to the TCP header, or NULL if there is not a complete TCP
2613 * header present in the packet.
2614 *
2615 * This is a short-cut function enabling quick and easy access to the TCP
2616 * header if that is all you care about. However, we recommend the use of the
2617 * more generic trace_get_transport() function instead.
2618 *
2619 * @note Unlike trace_get_transport(), this function will return NULL if the
2620 * TCP header is incomplete or truncated.
2621 */
2622DLLEXPORT SIMPLE_FUNCTION
2623libtrace_tcp_t *trace_get_tcp(libtrace_packet_t *packet);
2624
2625/** Get a pointer to the TCP header following an IPv4 header (if present)
2626 * @param ip            The IP header to find the subsequent TCP header for
2627 * @param[in,out] remaining Updated with the number of captured bytes remaining
2628 *
2629 * @return A pointer to the TCP header, or NULL if no TCP header is present in
2630 * the packet.
2631 *
2632 * When calling this function, remaining must contain the number of captured
2633 * bytes remaining in the packet starting from the IP header (including the
2634 * IP header itself). remaining will be updated to contain the number of
2635 * bytes remaining after the IP header has been skipped.
2636 *
2637 * If the IP header is complete but there are zero bytes of payload after
2638 * the IP header, a pointer to where the payload would be is returned and
2639 * remaining will be set to 0.  If the IP header is incomplete, NULL will be
2640 * returned and remaining will be set to 0. Therefore, it is important to check
2641 * the value of remaining after calling this function.
2642 *
2643 * @note This function is rather redundant now that the layer 3 header is
2644 * cached. There should be no performance advantage for the user to call this
2645 * function over just calling trace_get_transport().
2646 *
2647 * @note The last parameter has changed from libtrace2
2648 */
2649DLLEXPORT SIMPLE_FUNCTION
2650libtrace_tcp_t *trace_get_tcp_from_ip(libtrace_ip_t *ip, uint32_t *remaining);
2651
2652/** Get a pointer to the UDP header (if present)
2653 * @param packet        The packet to get the UDP header from
2654 *
2655 * @return A pointer to the UDP header, or NULL if there is not a complete UDP
2656 * header present in the packet.
2657 *
2658 * This is a short-cut function enabling quick and easy access to the UDP
2659 * header if that is all you care about. However, we recommend the use of the
2660 * more generic trace_get_transport() function instead.
2661 *
2662 * @note Unlike trace_get_transport(), this function will return NULL if the
2663 * UDP header is incomplete or truncated.
2664 */
2665DLLEXPORT SIMPLE_FUNCTION
2666libtrace_udp_t *trace_get_udp(libtrace_packet_t *packet);
2667
2668/** Get a pointer to the UDP header following an IPv4 header (if present)
2669 * @param ip            The IP header to find the subsequent UDP header for
2670 * @param[in,out] remaining Updated with the number of captured bytes remaining
2671 *
2672 * @return A pointer to the UDP header, or NULL if no UDP header is present in
2673 * the packet.
2674 *
2675 * When calling this function, remaining must contain the number of captured
2676 * bytes remaining in the packet starting from the IP header (including the
2677 * IP header itself). remaining will be updated to contain the number of
2678 * bytes remaining after the IP header has been skipped.
2679 *
2680 * If the IP header is complete but there are zero bytes of payload after
2681 * the IP header, a pointer to where the payload would be is returned and
2682 * remaining will be set to 0.  If the IP header is incomplete, NULL will be
2683 * returned and remaining will be set to 0. Therefore, it is important to check
2684 * the value of remaining after calling this function.
2685 *
2686 * @note This function is rather redundant now that the layer 3 header is
2687 * cached. There should be no performance advantage for the user to call this
2688 * function over just calling trace_get_transport().
2689 *
2690 * @note The last parameter has changed from libtrace2
2691 */
2692DLLEXPORT SIMPLE_FUNCTION
2693libtrace_udp_t *trace_get_udp_from_ip(libtrace_ip_t *ip,uint32_t *remaining);
2694
2695/** Get a pointer to the ICMP header (if present)
2696 * @param packet        The packet to get the ICMP header from
2697 *
2698 * @return A pointer to the ICMP header, or NULL if there is not a complete
2699 * ICMP header present in the packet.
2700 *
2701 * This is a short-cut function enabling quick and easy access to the ICMP
2702 * header if that is all you care about. However, we recommend the use of the
2703 * more generic trace_get_transport() function instead.
2704 *
2705 * @note Unlike trace_get_transport(), this function will return NULL if the
2706 * ICMP header is incomplete or truncated.
2707 */
2708DLLEXPORT SIMPLE_FUNCTION
2709libtrace_icmp_t *trace_get_icmp(libtrace_packet_t *packet);
2710
2711/** Get a pointer to the ICMPv6 header (if present)
2712 * @param packet        The packet to get the ICMPv6 header from
2713 *
2714 * @return A pointer to the ICMPv6 header, or NULL if there is not a complete
2715 * ICMP header present in the packet.
2716 *
2717 * This is a short-cut function enabling quick and easy access to the ICMPv6
2718 * header if that is all you care about. However, we recommend the use of the
2719 * more generic trace_get_transport() function instead.
2720 *
2721 * @note Unlike trace_get_transport(), this function will return NULL if the
2722 * ICMPv6 header is incomplete or truncated.
2723 */
2724DLLEXPORT SIMPLE_FUNCTION
2725libtrace_icmp6_t *trace_get_icmp6(libtrace_packet_t *packet);
2726
2727/** Get a pointer to the ICMP header following an IPv4 header (if present)
2728 * @param ip            The IP header to find the subsequent ICMP header for
2729 * @param[in,out] remaining Updated with the number of captured bytes remaining
2730 *
2731 * @return A pointer to the ICMP header, or NULL if no UDP header is present in
2732 * the packet.
2733 *
2734 * When calling this function, remaining must contain the number of captured
2735 * bytes remaining in the packet starting from the IP header (including the
2736 * IP header itself). remaining will be updated to contain the number of
2737 * bytes remaining after the IP header has been skipped.
2738 *
2739 * If the IP header is complete but there are zero bytes of payload after
2740 * the IP header, a pointer to where the payload would be is returned and
2741 * remaining will be set to 0.  If the IP header is incomplete, NULL will be
2742 * returned and remaining will be set to 0. Therefore, it is important to check
2743 * the value of remaining after calling this function.
2744 *
2745 * @note This function is rather redundant now that the layer 3 header is
2746 * cached. There should be no performance advantage for the user to call this
2747 * function over just calling trace_get_transport().
2748 *
2749 * @note The last parameter has changed from libtrace2
2750 */
2751DLLEXPORT SIMPLE_FUNCTION
2752libtrace_icmp_t *trace_get_icmp_from_ip(libtrace_ip_t *ip,uint32_t *remaining);
2753
2754/** Get a pointer to the OSPF header (if present)
2755 * @param packet        The packet to get the OSPF header from
2756 * @param[out] version  The OSPF version number
2757 * @param[out] remaining        Updated with the number of captured bytes remaining
2758 * @return A pointer to the start of the OSPF header or NULL if there is no
2759 * complete OSPF header present in the packet
2760 *
2761 * This is a short-cut function enabling quick and easy access to the OSPF
2762 * header. If you only care about the OSPF header, this function may be useful
2763 * but we otherwise recommend the use of the more generic trace_get_transport()
2764 * function instead.
2765 *
2766 * Upon return, 'version' is updated to contain the OSPF version number for the
2767 * packet so that the returned pointer may be cast to the correct type.
2768 * The version parameter MUST contain a valid pointer; it MUST NOT be NULL.
2769 *
2770 * 'remaining' is also set to contain the number of captured bytes remaining
2771 * starting from the pointer returned by this function.
2772 *
2773 * @note Unlike trace_get_transport(), this function will return NULL if the
2774 * OSPF header is incomplete or truncated.
2775 */
2776DLLEXPORT SIMPLE_FUNCTION
2777void *trace_get_ospf_header(libtrace_packet_t *packet, uint8_t *version,
2778                uint32_t *remaining);
2779
2780/** Get a pointer to the contents of the OSPF packet *after* the OSPF header
2781 * @param header        The OSPF header to get the OSPF contents from
2782 * @param[out] ospf_type        The OSPF packet type
2783 * @param[in, out] remaining    Updated with the number of captured bytes remaining
2784 * @return A pointer to the first byte after the OSPF header.
2785 *
2786 * This function returns a void pointer that can be cast appropriately
2787 * based on the ospf_type. For example, if the ospf_type is TRACE_OSPF_HELLO
2788 * then the return pointer should be cast as a libtrace_ospf_hello_v2_t
2789 * structure.
2790 *
2791 * If the OSPF header is truncated, then NULL will be returned. If the OSPF
2792 * contents are missing or truncated, the pointer to the start of the content
2793 * will still be returned so be careful to check the value of remaining.
2794 *
2795 * 'remaining' MUST be set to the amount of bytes remaining in the captured
2796 * packet starting from the beginning of the OSPF header. It will be updated
2797 * to contain the number of bytes remaining from the start of the OSPF contents.
2798 *
2799 * @note This function only works for OSPF version 2 packets.
2800 * @note Use trace_get_first_ospf_lsa_v2_from_X() and trace_get_next_ospf_lsa_v2() to read the LSAs from Link State Update packets.
2801 * @note Use trace_get_first_ospf_lsa_v2_from_X() and trace_get_next_ospf_lsa_header_v2() to read the LSA headers from Link State Ack packets.
2802 *
2803 */
2804DLLEXPORT SIMPLE_FUNCTION
2805void *trace_get_ospf_contents_v2(libtrace_ospf_v2_t *header,
2806                uint8_t *ospf_type, uint32_t *remaining);
2807
2808/** Get a pointer to the start of the first LSA contained within an LS Update packet
2809 * @param ls_update     Pointer to the LS Update header
2810 * @param[in,out] remaining     Updated with the number of captured bytes remaining
2811 * @return A pointer to the first LSA in the packet.
2812 *
2813 * This function simply skips past the LS Update header to provide a suitable
2814 * pointer to pass into trace_get_next_ospf_lsa_v2.
2815 *
2816 * If the OSPF packet is truncated, then NULL will be returned.
2817 *
2818 * 'remaining' MUST be set to the amount of bytes remaining in the captured
2819 * packet starting from the beginning of the LS Update header. It will be
2820 * updated to contain the number of bytes remaining from the start of the
2821 * first LSA.
2822 *
2823 * @note This function only works for OSPF version 2 packets.
2824 * @note trace_get_next_ospf_lsa_v2() should be subsequently used to process the LSAs
2825 */
2826DLLEXPORT SIMPLE_FUNCTION
2827unsigned char *trace_get_first_ospf_lsa_from_update_v2(
2828                libtrace_ospf_ls_update_t *ls_update,
2829                uint32_t *remaining);
2830
2831/** Get a pointer to the start of the first LSA contained within an Database Description packet
2832 * @param db_desc       Pointer to the Database Description header
2833 * @param[in,out] remaining     Updated with the number of captured bytes remaining
2834 * @return A pointer to the first LSA in the packet.
2835 *
2836 * This function simply skips past the Database Description header to provide a
2837 * suitable pointer to pass into trace_get_next_ospf_lsa_header_v2.
2838 *
2839 * If the OSPF packet is truncated, then NULL will be returned.
2840 *
2841 * 'remaining' MUST be set to the amount of bytes remaining in the captured
2842 * packet starting from the beginning of the Database Description header. It
2843 * will be updated to contain the number of bytes remaining from the start of
2844 * the first LSA.
2845 *
2846 * @note This function only works for OSPF version 2 packets.
2847 * @note trace_get_next_ospf_lsa_header_v2() should be subsequently used to process the LSA headers
2848 */
2849DLLEXPORT SIMPLE_FUNCTION
2850unsigned char *trace_get_first_ospf_lsa_from_db_desc_v2(
2851                libtrace_ospf_db_desc_v2_t *db_desc,
2852                uint32_t *remaining);
2853
2854/** Get a pointer to the start of the first link contained within a Router LSA
2855 * @param lsa   Pointer to the Router LSA
2856 * @param[in,out] remaining     Updated with the number of captured bytes remaining
2857 * @return A pointer to the first link in the packet.
2858 *
2859 * This function simply skips past the Router LSA header to provide a
2860 * suitable pointer to pass into trace_get_next_ospf_link_v2.
2861 *
2862 * If the OSPF packet is truncated, then NULL will be returned.
2863 *
2864 * 'remaining' MUST be set to the amount of bytes remaining in the captured
2865 * packet starting from the beginning of the Router LSA (not including the LSA
2866 * header) header. It will be updated to contain the number of bytes remaining
2867 * from the start of the first Link.
2868 *
2869 * @note This function only works for OSPF version 2 packets.
2870 * @note trace_get_next_ospf_link_v2() should be subsequently used to process
2871 * the links
2872 */
2873DLLEXPORT SIMPLE_FUNCTION
2874unsigned char *trace_get_first_ospf_link_from_router_lsa_v2(
2875                libtrace_ospf_router_lsa_v2_t *lsa,
2876                uint32_t *remaining);
2877
2878/** Parses an OSPF Router LSA Link and finds the next Link (if there is one)
2879 * @param[in,out] current       Pointer to the next Link (updated by this function)
2880 * @param[out] link             Set to point to the Link located at the original value of current
2881 * @param[in,out] remaining     Updated with the number of captured bytes remaining
2882 * @param[out] link_len         Set to the size of the Link pointed to by 'link'
2883 * @return 0 if there are no more links after the current one, 1 otherwise.
2884 *
2885 * When called, 'current' MUST point to an OSPF Router LSA link. Ideally, this
2886 * would come from either a call to
2887 * trace_get_first_ospf_link_from_router_lsa_v2() or a previous call of this
2888 * function.
2889 *
2890 * 'link' will be set to the value of 'current', so that the caller may then
2891 * do any processing they wish on that particular link. 'current' is advanced
2892 * to point to the next link and 'link_len' is updated to report the size of
2893 * the original link.
2894 *
2895 * 'remaining' MUST be set to the amount of bytes remaining in the captured
2896 * packet starting from the beginning of the Link pointed to by 'current'.
2897 * It will be updated to contain the number of bytes remaining from the start
2898 * of the next link.
2899 *
2900 * If this function returns 0 but 'link' is NOT NULL, that link is still valid
2901 * but there are no more links after this one.
2902 * If this function returns 0 AND link is NULL, the link is obviously not
2903 * suitable for processing.
2904 *
2905 * @note This function only works for OSPF version 2 packets.
2906 */
2907DLLEXPORT SIMPLE_FUNCTION
2908int trace_get_next_ospf_link_v2(unsigned char **current,
2909                libtrace_ospf_link_v2_t **link,
2910                uint32_t *remaining,
2911                uint32_t *link_len);
2912
2913/** Parses an OSPF LSA and finds the next LSA (if there is one)
2914 * @param[in,out] current       Pointer to the next LSA (updated by this function)
2915 * @param[out] lsa_hdr          Set to point to the header of the LSA located at the original value of current
2916 * @param[out] lsa_body         Set to point to the body of the LSA located at the original value of current
2917 * @param[in,out] remaining     Updated with the number of captured bytes remaining
2918 * @param[out] lsa_type         Set to the type of the LSA located at the original value of current
2919 * @param[out] lsa_length       Set to the size of the LSA located at the original value of current
2920 * @return 1 if there are more LSAs after the current one, 0 if there are no more LSAs to come, and -1 if the current LSA is incomplete, truncated or invalid.
2921 *
2922 * When called, 'current' MUST point to an OSPF LSA. Ideally, this would come
2923 * from either a call to trace_get_first_ospf_lsa_from_update_v2() or a
2924 * previous call of this function.
2925 *
2926 * This function should only be used to access COMPLETE LSAs, i.e. LSAs that
2927 * have both a header and a body. In OSPFv2, only the LSAs contained within
2928 * LSA Update packets meet this requirement. trace_get_next_ospf_lsa_header_v2
2929 * should be used to read header-only LSAs, e.g. those present in LS Acks.
2930 *
2931 * 'lsa_hdr' will be set to the value of 'current', so that the caller may then
2932 * do any processing they wish on that particular LSA. 'lsa_body' will be set
2933 * to point to the first byte after the LSA header. 'current' is advanced
2934 * to point to the next LSA. 'lsa_length' is updated to contain the size of
2935 * the parsed LSA, while 'lsa_type' is set to indicate the LSA type.
2936 *
2937 * 'remaining' MUST be set to the amount of bytes remaining in the captured
2938 * packet starting from the beginning of the LSA pointed to by 'current'.
2939 * It will be updated to contain the number of bytes remaining from the start
2940 * of the next LSA.
2941 *
2942 * If this function returns 0 but 'lsa_hdr' is NOT NULL, that LSA is still
2943 * valid but there are no more LSAs after this one.
2944 * If this function returns 0 AND 'lsa_hdr' is NULL, the LSA is obviously not
2945 * suitable for processing.
2946 *
2947 * It is also recommended to check the value of 'lsa_body' before
2948 * de-referencing it. 'lsa_body' will be set to NULL if there is only an LSA
2949 * header present.
2950 *
2951 * @note This function only works for OSPF version 2 packets.
2952 *
2953 */
2954DLLEXPORT SIMPLE_FUNCTION
2955int trace_get_next_ospf_lsa_v2(unsigned char **current,
2956                libtrace_ospf_lsa_v2_t **lsa_hdr,
2957                unsigned char **lsa_body,
2958                uint32_t *remaining,
2959                uint8_t *lsa_type,
2960                uint16_t *lsa_length);
2961
2962/** Parses an OSPF LSA header and finds the next LSA (if there is one)
2963 * @param[in,out] current       Pointer to the next LSA (updated by this function)
2964 * @param[out] lsa_hdr          Set to point to the header of the LSA located at the original value of current
2965 * @param[in,out] remaining     Updated with the number of captured bytes remaining
2966 * @param[out] lsa_length       Set to the size of the LSA located at the original value of current
2967 * @return 1 if there are more LSAs after the current one, 0 if there are no more LSAs to come, and -1 if the current LSA is incomplete, truncated or invalid.
2968 *
2969 * When called, 'current' MUST point to an OSPF LSA. Ideally, this would come
2970 * from either a call to trace_get_first_ospf_lsa_from_db_desc_v2() or a
2971 * previous call of this function.
2972 *
2973 * This function should only be used to access LSA headers, i.e. LSAs that
2974 * have a header only. In OSPFv2, the LSAs contained within LSA Ack and
2975 * Database Description packets meet this requirement.
2976 * trace_get_next_ospf_lsa_v2 should be used to read full LSAs, e.g. those
2977 * present in LS Updates.
2978 *
2979 * 'lsa_hdr' will be set to the value of 'current', so that the caller may then
2980 * do any processing they wish on that particular LSA header. 'current' is
2981 * advanced to point to the next LSA header. 'lsa_length' is updated to contain
2982 * the size of the parsed LSA header.
2983 *
2984 * 'remaining' MUST be set to the amount of bytes remaining in the captured
2985 * packet starting from the beginning of the LSA pointed to by 'current'.
2986 * It will be updated to contain the number of bytes remaining from the start
2987 * of the next LSA.
2988 *
2989 * If this function returns 0 but 'lsa_hdr' is NOT NULL, that LSA is still
2990 * valid but there are no more LSAs after this one.
2991 * If this function returns 0 AND 'lsa_hdr' is NULL, the LSA is obviously not
2992 * suitable for processing.
2993 *
2994 * @note This function only works for OSPF version 2 packets.
2995 *
2996 */
2997DLLEXPORT SIMPLE_FUNCTION
2998int trace_get_next_ospf_lsa_header_v2(unsigned char **current,
2999                libtrace_ospf_lsa_v2_t **lsa_hdr,
3000                uint32_t *remaining,
3001                uint8_t *lsa_type,
3002                uint16_t *lsa_length);
3003
3004/** Extracts the metric field from an AS External LSA packet
3005 *
3006 * @param as_lsa        The AS External LSA
3007 * @returns The value of the metric field
3008 *
3009 * The metric field in the AS External LSA packet is a 24-bit value, which
3010 * is difficult to extract correctly. To avoid byte-ordering issues, use this
3011 * function which will extract the correct value for you.
3012 */
3013DLLEXPORT SIMPLE_FUNCTION
3014uint32_t trace_get_ospf_metric_from_as_external_lsa_v2(
3015                libtrace_ospf_as_external_lsa_v2_t *as_lsa);
3016
3017/** Extracts the metric field from a Summary LSA packet
3018 *
3019 * @param sum_lsa       The Summary LSA
3020 * @returns The value of the metric field
3021 *
3022 * The metric field in the Summary LSA packet is a 24-bit value, which
3023 * is difficult to extract correctly. To avoid byte-ordering issues, use this
3024 * function which will extract the correct value for you.
3025 */
3026DLLEXPORT SIMPLE_FUNCTION
3027uint32_t trace_get_ospf_metric_from_summary_lsa_v2(
3028                libtrace_ospf_summary_lsa_v2_t *sum_lsa);
3029
3030
3031/** Gets the destination MAC address for a given packet
3032 * @param packet        The packet to extract the destination MAC address from
3033 *
3034 * @return A pointer to the destination MAC address field in the layer 2
3035 * header, (or NULL if there is no destination MAC address or layer 2 header
3036 * available)
3037 *
3038 * @note This is a zero-copy function, so the memory that the returned pointer
3039 * points to is part of the packet itself.
3040 */
3041DLLEXPORT SIMPLE_FUNCTION
3042uint8_t *trace_get_destination_mac(libtrace_packet_t *packet);
3043
3044/** Gets the source MAC address for a given packet
3045 * @param packet        The packet to extract the source MAC address from
3046 *
3047 * @return A pointer to the source MAC address field in the layer 2
3048 * header, (or NULL if there is no source MAC address or layer 2 header
3049 * available)
3050 *
3051 * @note This is a zero-copy function, so the memory that the returned pointer
3052 * points to is part of the packet itself.
3053 */
3054DLLEXPORT SIMPLE_FUNCTION
3055uint8_t *trace_get_source_mac(libtrace_packet_t *packet);
3056
3057/** Get the source IP address for a given packet
3058 * @param packet        The packet to extract the source IP address from
3059 * @param addr          A pointer to a sockaddr structure to store the address
3060 *                      in. If NULL, static storage is used instead.
3061 * @return A pointer to a sockaddr holding a v4 or v6 IP address or on some
3062 * platforms a sockaddr holding a MAC address. Returns NULL if no source IP
3063 * address was available.
3064 *
3065 * @note The best way to use this function is to pass in a pointer to the
3066 * struct sockaddr_storage for the addr parameter. This will avoid problems
3067 * with trying to shoe-horn an IPv6 address into a sockaddr that only supports
3068 * IPv4.
3069 */
3070DLLEXPORT SIMPLE_FUNCTION
3071struct sockaddr *trace_get_source_address(const libtrace_packet_t *packet,
3072                struct sockaddr *addr);
3073
3074/** Get the source IP address for a packet and convert it into a string
3075 * @param packet        The packet to extract the source IP address from
3076 * @param space         A pointer to a character buffer to store the address
3077 *                      in. If NULL, static storage is used instead.
3078 * @param spacelen      The size of the buffer passed in via 'space'. Set this
3079 *                      to zero if you are going to pass in a NULL buffer.
3080 * @return A pointer to a character buffer containing the string representation
3081 * of the source IP address. For packets where there is no suitable IP address,
3082 * the source MAC will be returned instead. Returns NULL if no valid address
3083 * is available.
3084 *
3085 * @note Be wary of the possibility of the address being an IPv6 address - make
3086 * sure your buffer is large enough!
3087 *
3088 * New in libtrace 3.0.17.
3089 */
3090DLLEXPORT SIMPLE_FUNCTION
3091char *trace_get_source_address_string(const libtrace_packet_t *packet,
3092                char *space, int spacelen);
3093
3094/** Get the destination IP address for a given packet
3095 * @param packet        The packet to extract the destination IP address from
3096 * @param addr          A pointer to a sockaddr structure to store the address
3097 *                      in. If NULL, static storage is used instead.
3098 * @return A pointer to a sockaddr holding a v4 or v6 IP address or on some
3099 * platforms a sockaddr holding a MAC address. Returns NULL if no destination
3100 * IP address was available.
3101 *
3102 * @note The best way to use this function is to pass in a pointer to the
3103 * struct sockaddr_storage for the addr parameter. This will avoid problems
3104 * with trying to shoe-horn an IPv6 address into a sockaddr that only supports
3105 * IPv4.
3106 */
3107DLLEXPORT SIMPLE_FUNCTION
3108struct sockaddr *trace_get_destination_address(const libtrace_packet_t *packet,
3109                struct sockaddr *addr);
3110
3111/** Get the destination IP address for a packet and convert it into a string
3112 * @param packet        The packet to extract the destination IP address from
3113 * @param space         A pointer to a character buffer to store the address
3114 *                      in. If NULL, static storage is used instead.
3115 * @param spacelen      The size of the buffer passed in via 'space'. Set this
3116 *                      to zero if you are going to pass in a NULL buffer.
3117 * @return A pointer to a character buffer containing the string representation
3118 * of the destination IP address. For packets where there is no suitable IP
3119 * address, the destination MAC will be returned instead. Returns NULL if no
3120 * valid address is available.
3121 *
3122 * @note Be wary of the possibility of the address being an IPv6 address - make
3123 * sure your buffer is large enough!
3124 *
3125 * New in libtrace 3.0.17.
3126 */
3127DLLEXPORT SIMPLE_FUNCTION
3128char *trace_get_destination_address_string(const libtrace_packet_t *packet,
3129                char *space, int spacelen);
3130
3131/** Parses an IP or TCP option
3132 * @param[in,out] ptr   The pointer to the current option
3133 * @param[in,out] len   The total length of all the remaining options
3134 * @param[out] type     The type of the option
3135 * @param[out] optlen   The length of the option
3136 * @param[out] data     The data of the option
3137 *
3138 * @return bool true if there is another option (and the fields are filled in)
3139 *               or false if this was the last option.
3140 *
3141 * This updates ptr to point to the next option after this one, and updates
3142 * len to be the number of bytes remaining in the options area.  Type is updated
3143 * to be the code of this option, and data points to the data of this option,
3144 * with optlen saying how many bytes there are.
3145 *
3146 * @note Beware of fragmented packets.
3147 */
3148DLLEXPORT int trace_get_next_option(unsigned char **ptr,int *len,
3149                        unsigned char *type,
3150                        unsigned char *optlen,
3151                        unsigned char **data);
3152
3153/*@}*/
3154
3155/** @name Time
3156 * These functions deal with the timestamp describing when a packet was
3157 * captured and can convert it into various formats
3158 * @{
3159 */
3160
3161/** Get the packet timestamp in the DAG time format
3162 * @param packet        The packet to extract the timestamp from
3163 *
3164 * @return a 64 bit timestamp in DAG ERF format (upper 32 bits are the seconds
3165 * past 1970-01-01, the lower 32bits are partial seconds)
3166 */
3167DLLEXPORT SIMPLE_FUNCTION
3168uint64_t trace_get_erf_timestamp(const libtrace_packet_t *packet);
3169
3170/** Get the packet timestamp as a struct timeval
3171 * @param packet        The packet to extract the timestamp from
3172 *
3173 * @return The time that this packet was captured in a struct timeval
3174 */
3175DLLEXPORT SIMPLE_FUNCTION
3176struct timeval trace_get_timeval(const libtrace_packet_t *packet);
3177
3178/** Get the packet timestamp as a struct timespec
3179 * @param packet        The packet to extract the timestamp from
3180 *
3181 * @return The time that this packet was captured in a struct timespec
3182 */
3183DLLEXPORT SIMPLE_FUNCTION
3184struct timespec trace_get_timespec(const libtrace_packet_t *packet);
3185
3186/** Get the packet timestamp in floating point seconds
3187 * @param packet        The packet to extract the timestamp from
3188 *
3189 * @return time that this packet was seen in 64-bit floating point seconds from
3190 * the UNIX epoch (1970-01-01 00:00:00 UTC).
3191 */
3192DLLEXPORT SIMPLE_FUNCTION
3193double trace_get_seconds(const libtrace_packet_t *packet);
3194
3195/** Seek within an input trace to a time specified in floating point seconds
3196 * @param trace         The input trace to seek within
3197 * @param seconds       The time to seek to, in floating point seconds
3198 * @return 0 on success, -1 if the seek fails. Use trace_perror() to determine
3199 * the error that occurred.
3200 *
3201 * This will make the next packet read to be the first packet to occur at or
3202 * after the specified time.  This must be called in the configuration state
3203 * (i.e. before trace_start() or after trace_pause()).
3204 *
3205 * The time format accepted by this function is 64-bit floating point seconds
3206 * since the UNIX epoch (1970-01-01 00:00:00 UTC), i.e. the same format as
3207 * trace_get_seconds().
3208 *
3209 * @note This function may be extremely slow.
3210 */
3211DLLEXPORT int trace_seek_seconds(libtrace_t *trace, double seconds);
3212
3213/** Seek within an input trace to a time specified as a timeval
3214 * @param trace         The input trace to seek within
3215 * @param tv            The time to seek to, as a timeval
3216 *
3217 * @return 0 on success, -1 if the seek fails. Use trace_perror() to determine
3218 * the error that occurred.
3219 *
3220 * This will make the next packet read to be the first packet to occur at or
3221 * after the specified time.  This must be called in the configuration state
3222 * (i.e. before trace_start() or after trace_pause()).
3223 *
3224 * @note This function may be extremely slow.
3225 */
3226DLLEXPORT int trace_seek_timeval(libtrace_t *trace, struct timeval tv);
3227
3228/** Seek within an input trace to a time specified as an ERF timestamp
3229 * @param trace         The input trace to seek within
3230 * @param ts            The time to seek to, as an ERF timestamp
3231 *
3232 * @return 0 on success, -1 if the seek fails. Use trace_perror() to determine
3233 * the error that occurred.
3234 *
3235 * This will make the next packet read to be the first packet to occur at or
3236 * after the specified time.  This must be called in the configuration state
3237 * (i.e. before trace_start() or after trace_pause()).
3238 *
3239 * The time format accepted by this function is the ERF timestamp, which is a
3240 * 64-bit value where the upper 32 bits are seconds since the UNIX epoch and
3241 * the lower 32 bits are partial seconds.
3242 *
3243 * @note This function may be extremely slow.
3244 */
3245DLLEXPORT int trace_seek_erf_timestamp(libtrace_t *trace, uint64_t ts);
3246
3247/*@}*/
3248
3249/** @name Sizes
3250 * This section deals with finding or setting the various different lengths
3251 * that a packet can have, e.g. capture lengths, wire lengths, etc.
3252 * @{
3253 */
3254/** Get the current size of the packet (in bytes), taking into account any
3255 * truncation or snapping that may have previously been performed.
3256 *
3257 * @param packet        The packet to determine the capture length for
3258 * @return The size of the packet read from the input trace, i.e. what is
3259 * actually available to libtrace at the moment.
3260 *
3261 * @note Most traces are header captures, so this value may not be the same
3262 * as the size of the packet when it was captured. Use trace_get_wire_length()
3263 * to get the original size of the packet.
3264 
3265 * @note This can (and often is) different for different packets in a trace!
3266 
3267 * @note This is sometimes called the "snaplen".
3268 *
3269 * @note The return size refers to the network-level payload of the packet and
3270 * does not include any capture framing headers. For example, an Ethernet
3271 * packet with an empty TCP packet will return sizeof(ethernet_header) +
3272 * sizeof(ip_header) + sizeof(tcp_header), but not the capture format
3273 * (pcap/erf/etc) header.
3274 */
3275DLLEXPORT SIMPLE_FUNCTION
3276size_t trace_get_capture_length(const libtrace_packet_t *packet);
3277
3278/** Get the size of the packet as it was originally seen on the wire (in bytes).
3279 * @param packet        The packet to determine the wire length for
3280 * @return The size of the packet as it was on the wire.
3281 *
3282 * @note This value may not be the same as the capture length, due to
3283 * truncation.
3284 *
3285 * @note trace_get_wire_length \em includes  the Frame Check Sequence. This is
3286 * different behaviour compared to most PCAP-based tools.
3287 *
3288 * @note The return size refers to the network-level payload of the packet and
3289 * does not include any capture framing headers. For example, an Ethernet
3290 * packet with an empty TCP packet will return sizeof(ethernet_header) +
3291 * sizeof(ip_header) + sizeof(tcp_header), but not the capture format
3292 * (pcap/erf/etc) header.
3293 */
3294DLLEXPORT SIMPLE_FUNCTION
3295size_t trace_get_wire_length(const libtrace_packet_t *packet);
3296
3297/** Get the length of the capture framing headers (in bytes).
3298 * @param packet        The packet to determine the framing length for
3299 * @return The size of the capture format header encapsulating the packet.
3300 *
3301 * @note This length corresponds to the difference between the amount of
3302 * memory required to store a captured packet and the capture length reported
3303 * by trace_capture_length()
3304 */
3305DLLEXPORT SIMPLE_FUNCTION
3306size_t trace_get_framing_length(const libtrace_packet_t *packet);
3307
3308/** Get the length of the original payload content of the packet (in bytes).
3309 * @param packet        The packet to determine the payload length for
3310 * @return The size of the packet payload (without headers). Returns 0 if
3311 * unable to calculate payload length correctly.
3312 *
3313 * This function reports the amount of data that followed the transport header
3314 * when the packet was originally captured, i.e. prior to any snapping. Best
3315 * described as the wire length minus the packet headers.
3316 *
3317 * Currently only supports some protocols and will return 0 if an unsupported
3318 * protocol header is encountered, or if one of the headers is truncated.
3319 *
3320 * @note Supports IPv4, IPv6, TCP, UDP and ICMP.
3321 */
3322DLLEXPORT SIMPLE_FUNCTION
3323size_t trace_get_payload_length(const libtrace_packet_t *packet);
3324
3325/** Truncate ("snap") the packet to the suggested length
3326 * @param packet        The packet to truncate
3327 * @param size          The new length of the packet (in bytes)
3328 *
3329 * @return The new capture length of the packet or the original capture
3330 * length of the packet if unchanged.
3331 *
3332 * This function will modify the capture length of the given packet. The wire
3333 * length will not be changed, so you can always determine what the original
3334 * packet size was, prior to the truncation.
3335 *
3336 * @note You can only use this function to decrease the capture length. Any
3337 * attempt to increase capture length will have no effect.
3338 */
3339DLLEXPORT size_t trace_set_capture_length(libtrace_packet_t *packet, size_t size);
3340
3341/*@}*/
3342
3343
3344/** Gets the link layer type for a packet
3345 * @param packet        The packet to extract the link layer type for
3346 * @return A libtrace_linktype_t describing the link layer protocol being used
3347 * by this packet.
3348 */
3349DLLEXPORT SIMPLE_FUNCTION
3350libtrace_linktype_t trace_get_link_type(const libtrace_packet_t *packet);
3351
3352/** Set the direction flag for a packet, if the capture format supports
3353 * direction tagging.
3354 *
3355 * @param packet        The packet to set the direction for
3356 * @param direction     The new direction
3357 * @returns -1 on error, or the direction that was set.
3358 *
3359 * @note Few capture formats actually support direction tagging. Most notably,
3360 * we cannot set the direction on PCAP packets.
3361 */
3362DLLEXPORT libtrace_direction_t trace_set_direction(libtrace_packet_t *packet, libtrace_direction_t direction);
3363
3364/** Get the direction flag for a packet, if it has one.
3365 * @param packet  The packet to get the direction for
3366 *
3367 * @return A value representing the direction flag, or -1 if this is not
3368 * supported by the capture format.
3369 *
3370 * The direction is defined as 0 for packets originating locally (ie, outbound)
3371 * and 1 for packets originating remotely (ie, inbound). Other values are
3372 * possible, which might be overloaded to mean special things for certain
3373 * traces, e.g. in the Waikato traces, 2 is used to represent an "Unknown"
3374 * direction.
3375 *
3376 * For DAG/ERF traces, the direction is extracted from the "Interface" bits in
3377 * the ERF header, which can range from 0 - 3.
3378 */
3379DLLEXPORT SIMPLE_FUNCTION
3380libtrace_direction_t trace_get_direction(const libtrace_packet_t *packet);
3381
3382/** @name BPF
3383 * This section deals with using Berkley Packet Filters to filter input traces
3384 * @{
3385 */
3386/** Creates a BPF filter
3387 * @param filterstring The filter string describing the BPF filter to create
3388 * @return An opaque pointer to a libtrace_filter_t object
3389 *
3390 * @note The filter is not actually compiled at this point, so no correctness
3391 * tests are performed here. trace_create_filter() will always return ok, but
3392 * if the filter is poorly constructed an error will be generated when the
3393 * filter is actually used.
3394 */
3395DLLEXPORT SIMPLE_FUNCTION
3396libtrace_filter_t *trace_create_filter(const char *filterstring);
3397
3398/** Create a BPF filter based on pre-compiled byte-code.
3399 * @param bf_insns      A pointer to the start of the byte-code
3400 * @param bf_len        The number of BPF instructions 
3401 * @return              An opaque pointer to a libtrace_filter_t object
3402 * @note                The supplied byte-code is not checked for correctness.
3403 *                      Instead, incorrect byte-code will generate an error
3404 *                      once the filter is actually used.
3405 * @author              Scott Raynel
3406 */
3407DLLEXPORT libtrace_filter_t *
3408trace_create_filter_from_bytecode(void *bf_insns, unsigned int bf_len);
3409
3410/** Apply a BPF filter to a packet
3411 * @param filter        The filter to be applied       
3412 * @param packet        The packet to be matched against the filter
3413 * @return >0 if the filter matches, 0 if it doesn't, -1 on error.
3414 *
3415 * @note Due to the way BPF filters are built, the filter is not actually
3416 * compiled until the first time trace_create_filter is called. If your filter
3417 * is incorrect, it will generate an error message and assert, exiting the
3418 * program. This behaviour may change to a more graceful handling of this error
3419 * in the future.
3420 */
3421DLLEXPORT int trace_apply_filter(libtrace_filter_t *filter,
3422                const libtrace_packet_t *packet);
3423
3424/** Destroy a BPF filter
3425 * @param filter        The filter to be destroyed
3426 *
3427 * Deallocates all the resources associated with a BPF filter.
3428 */
3429DLLEXPORT void trace_destroy_filter(libtrace_filter_t *filter);
3430/*@}*/
3431
3432/** @name Portability
3433 * This section contains functions that deal with portability issues, e.g. byte
3434 * ordering.
3435 * @{
3436 */
3437
3438/** Converts an ethernet address to a printable string
3439 * @param addr  Ethernet address in network byte order
3440 * @param buf   Buffer to store the ascii representation, or NULL to indicate
3441 * that static storage should be used.
3442 * @return buf, or if buf is NULL then a statically allocated buffer.
3443 *
3444 * This function is similar to the GNU ether_ntoa_r function, with a few
3445 * minor differences.  If NULL is passed as buf, then the function will
3446 * use an internal static buffer. If NULL isn't passed then the function
3447 * will use that buffer instead.
3448 *
3449 * The address pointers returned by trace_get_source_mac() and
3450 * trace_get_destination_mac() can be passed directly into this function.
3451 *
3452 * @note The type of addr isn't struct ether_addr as it is with ether_ntoa_r,
3453 * however it is bit compatible so that a cast will work.
3454 */
3455DLLEXPORT char *trace_ether_ntoa(const uint8_t *addr, char *buf);
3456
3457/** Convert a string to an ethernet address
3458 * @param buf   A string containing an Ethernet address in hex format
3459 * delimited with :'s.
3460 * @param addr  Buffer to store the binary representation, or NULL to indicate
3461 * that static storage should be used.
3462 * @return addr, or if addr is NULL then a statically allocated buffer.
3463 *
3464 * This function is similar to the GNU ether_aton_r function, with a few
3465 * minor differences.  If NULL is passed as addr, then the function will
3466 * use an internal static buffer. If NULL isn't passed then the function will
3467 * use that buffer instead.
3468 *
3469 * The address returned by this function will be in network byte order.
3470 *
3471 * @note the type of addr isn't struct ether_addr as it is with ether_aton_r,
3472 * however it is bit compatible so that a cast will work.
3473 */
3474DLLEXPORT uint8_t *trace_ether_aton(const char *buf, uint8_t *addr);
3475
3476/*@}*/
3477
3478/** @name Ports
3479 * This section contains functions for dealing with port numbers at the
3480 * transport layer.
3481 *
3482 * @{
3483 */
3484
3485/** An indication of which port is the "server" port for a given port pair */
3486typedef enum {
3487        USE_DEST,       /**< Destination port is the server port */
3488        USE_SOURCE      /**< Source port is the server port */
3489} serverport_t;
3490
3491/** Gets the source port for a given packet
3492 * @param packet        The packet to get the source port from
3493 * @return The source port in HOST byte order or 0 if no suitable port number
3494 * can be extracted from the packet.
3495 *
3496 * This function will return 0 if the transport protocol is known not to
3497 * use port numbers, e.g. ICMP. 0 is also returned if no transport header is
3498 * present in the packet or the transport header has been truncated such that
3499 * the port fields are not readable.
3500 *
3501 * @note If the transport protocol is not known by libtrace, the first two
3502 * bytes of the transport header will be treated as the source port field.
3503 */
3504DLLEXPORT SIMPLE_FUNCTION
3505uint16_t trace_get_source_port(const libtrace_packet_t *packet);
3506
3507/** Gets the destination port for a given packet
3508 * @param packet        The packet to get the destination port from
3509 * @return The destination port in HOST byte order or 0 if no suitable port
3510 * number can be extracted from the packet.
3511 *
3512 * This function will return 0 if the transport protocol is known not to
3513 * use port numbers, e.g. ICMP. 0 is also returned if no transport header is
3514 * present in the packet or the transport header has been truncated such that
3515 * the port fields are not readable.
3516 *
3517 * @note If the transport protocol is not known by libtrace, the third and
3518 * fourth bytes of the transport header will be treated as the destination
3519 * port field.
3520 *
3521 */
3522DLLEXPORT SIMPLE_FUNCTION
3523uint16_t trace_get_destination_port(const libtrace_packet_t *packet);
3524
3525/** Hint at which of the two provided ports is the server port.
3526 *
3527 * @param protocol      The IP layer protocol, eg 6 (tcp), 17 (udp)
3528 * @param source        The source port from the packet
3529 * @param dest          The destination port from the packet
3530 *
3531 * @return one of USE_SOURCE or USE_DEST describing on which of the two ports
3532 * is most likely to be the server port.
3533 *
3534 * @note Ports must be provided in HOST byte order!
3535 *
3536 * This function is based almost entirely on heuristics and should not be
3537 * treated as a definitive means of identifying the server port. However, it
3538 * is deterministic, so it is very handy for identifying both halves of the
3539 * same flow.
3540 */
3541DLLEXPORT SIMPLE_FUNCTION
3542int8_t trace_get_server_port(uint8_t protocol, uint16_t source, uint16_t dest);
3543
3544/*@}*/
3545
3546/** @name Wireless trace support
3547 * Functions to access wireless information from packets that have wireless
3548 * monitoring headers such as Radiotap or Prism.
3549 *
3550 * The trace_get_wireless_* functions provide an abstract interface for
3551 * retrieving information from wireless traces. They take a pointer to the
3552 * wireless monitoring header (usually found with trace_get_packet_meta()) and
3553 * the linktype of the header passed in.
3554 *
3555 * All of the trace_get_wireless_* functions return false if the requested
3556 * information was unavailable, or true if it was. The actual data is stored
3557 * in an output variable supplied by the caller. Values returned into the
3558 * output variable will always be returned in host byte order.
3559 * @{
3560 */
3561
3562
3563#ifndef ARPHRD_80211_RADIOTAP
3564/** libc doesn't define this yet, so we have to do so ourselves */
3565#define ARPHRD_80211_RADIOTAP 803
3566#endif
3567
3568/** Get the wireless Timer Synchronisation Function
3569 *
3570 * Gets the value of the timer synchronisation function for this frame, which
3571 * is a value in microseconds indicating the time that the first bit of the
3572 * MPDU was received by the MAC.
3573 *
3574 * @param linkptr The wireless meta header
3575 * @param linktype The linktype of the wireless meta header passed in
3576 * @param[out] tsft The value of the timer synchronisation function.
3577 * @return true if the field was available, false if not.
3578 */
3579DLLEXPORT bool trace_get_wireless_tsft(void *linkptr,
3580        libtrace_linktype_t linktype, uint64_t *tsft);
3581
3582/** Get the wireless data rate
3583 *
3584 * @param linkptr The wireless meta header
3585 * @param linktype The linktype of the wireless meta header passed in
3586 * @param[out] rate The data-rate of the frame in units of 500kbps
3587 * @return true if the field was available, false if not.
3588 */
3589DLLEXPORT bool trace_get_wireless_rate(void *linkptr,
3590        libtrace_linktype_t linktype, uint8_t *rate);
3591
3592/** Get the wireless channel frequency
3593 * @param linkptr The wireless meta header
3594 * @param linktype The linktype of the wireless meta header passed in
3595 * @param[out] freq The frequency in MHz of the channel the frame was
3596 * transmitted or received on.
3597 * @return true if the field was available, false if not.
3598 */
3599DLLEXPORT bool trace_get_wireless_freq(void *linkptr,
3600        libtrace_linktype_t linktype, uint16_t *freq);
3601
3602/** Get the wireless signal strength in dBm
3603 * @param linkptr The wireless meta header
3604 * @param linktype The linktype of the wireless meta header passed in
3605 * @param[out] strength The RF signal power at the antenna, in dB difference
3606 * from 1mW.
3607 * @return true if the field was available, false if not.
3608 */
3609DLLEXPORT bool trace_get_wireless_signal_strength_dbm(void *linkptr,
3610        libtrace_linktype_t linktype, int8_t *strength);
3611
3612/** Get the wireless noise strength in dBm
3613 * @param linkptr The wireless meta header
3614 * @param linktype The linktype of the wireless meta header passed in
3615 * @param[out] strength The RF noise power at the antenna, in dB difference
3616 * from 1mW.
3617 * @return true if the field was available, false if not.
3618 */
3619DLLEXPORT bool trace_get_wireless_noise_strength_dbm(void *linkptr,
3620        libtrace_linktype_t linktype, int8_t *strength);
3621
3622/** Get the wireless signal strength in dB
3623 * @param linkptr The wireless meta header
3624 * @param linktype The linktype of the wireless meta header passed in
3625 * @param[out] strength The RF signal power at the antenna, in dB difference
3626 * from a fixed reference.
3627 * @return true if the field was available, false if not.
3628 */
3629DLLEXPORT bool trace_get_wireless_signal_strength_db(void *linkptr,
3630        libtrace_linktype_t linktype, uint8_t *strength);
3631
3632/** Get the wireless noise strength in dB
3633 * @param linkptr The wireless meta header
3634 * @param linktype The linktype of the wireless meta header passed in
3635 * @param[out] strength The RF noise power at the antenna, in dB difference
3636 * from a fixed reference.
3637 * @return true if the field was available, false if not.
3638 */
3639DLLEXPORT bool trace_get_wireless_noise_strength_db(void *linkptr,
3640        libtrace_linktype_t linktype, uint8_t *strength);
3641
3642/** Get the wireless transmit attenuation
3643 * @param linkptr The wireless meta header
3644 * @param linktype The linktype of the wireless meta header passed in
3645 * @param[out] attenuation The transmit power as a unitless distance from
3646 * maximum power set at factory calibration. 0 indicates maximum transmission
3647 * power.
3648 * @return true if the field was available, false if not.
3649 */
3650DLLEXPORT bool trace_get_wireless_tx_attenuation(void *linkptr,
3651        libtrace_linktype_t linktype, uint16_t *attenuation);
3652
3653/** Get the wireless transmit attenuation in dB
3654 * @param linkptr The wireless meta header
3655 * @param linktype The linktype of the wireless meta header passed in
3656 * @param[out] attenuation The transmit power as dB difference from maximum
3657 * power set at factory calibration. 0 indicates maximum power.
3658 * @return true if the field was available, false if not.
3659 */
3660DLLEXPORT bool trace_get_wireless_tx_attenuation_db(void *linkptr,
3661        libtrace_linktype_t linktype, uint16_t *attenuation);
3662
3663/** Get the wireless transmit power in dBm
3664 * @param linkptr The wireless meta header
3665 * @param linktype The linktype of the wireless meta header passed in
3666 * @param[out] txpower The transmit power as dB from a 1mW reference. This is
3667 * the absolute power level measured at the antenna port. 
3668 * @return true if the field was available, false if not.
3669 */
3670DLLEXPORT bool trace_get_wireless_tx_power_dbm(void *linkptr,
3671                libtrace_linktype_t linktype, int8_t *txpower);
3672
3673/** Get the wireless antenna
3674 * @param linkptr The wireless meta header
3675 * @param linktype The linktype of the wireless meta header passed in
3676 * @param[out] antenna The antenna that was used to transmit or receive the
3677 * frame.
3678 * @return true if the field was available, false if not.
3679 */
3680DLLEXPORT bool trace_get_wireless_antenna(void *linkptr,
3681        libtrace_linktype_t linktype, uint8_t *antenna);
3682
3683/*@}*/
3684
3685#ifdef __cplusplus
3686} /* extern "C" */
3687#endif /* #ifdef __cplusplus */
3688#endif /* LIBTRACE_H_ */
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