source: lib/libtrace.h.in @ 9cc1266

4.0.1-hotfixescachetimestampsdevelopdpdk-ndagetsilivegetfragoffhelplibtrace4ndag_formatpfringrc-4.0.1rc-4.0.2rc-4.0.3rc-4.0.4ringdecrementfixringperformanceringtimestampfixes
Last change on this file since 9cc1266 was 9cc1266, checked in by Shane Alcock <salcock@…>, 10 years ago
  • Fixed poor performance of the event API by greatly reducing the amount of packets created, copied and freed
  • We now cache the transport header and payload length for each packet
  • We now deal with Linux SLL Ethernet captures taken using tcpdump with -i any correctly.
  • Changed parameters for internal function trace_get_payload_from_sll - it now sets both the arphrd type and the next protocol
  • Moved ARPHRD definitions into a separate header file, as they come in handy anywhere we deal with SLL headers
  • Property mode set to 100644
File size: 95.5 KB
Line 
1/*
2 * This file is part of libtrace
3 *
4 * Copyright (c) 2007,2008,2009,2010 The University of Waikato, Hamilton,
5 * New Zealand.
6 *
7 * Authors: Daniel Lawson
8 *          Perry Lorier
9 *          Shane Alcock
10 *         
11 * All rights reserved.
12 *
13 * This code has been developed by the University of Waikato WAND
14 * research group. For further information please see http://www.wand.net.nz/
15 *
16 * libtrace is free software; you can redistribute it and/or modify
17 * it under the terms of the GNU General Public License as published by
18 * the Free Software Foundation; either version 2 of the License, or
19 * (at your option) any later version.
20 *
21 * libtrace is distributed in the hope that it will be useful,
22 * but WITHOUT ANY WARRANTY; without even the implied warranty of
23 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
24 * GNU General Public License for more details.
25 *
26 * You should have received a copy of the GNU General Public License
27 * along with libtrace; if not, write to the Free Software
28 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
29 *
30 * $Id$
31 *
32 */
33
34#ifndef LIBTRACE_H
35#define LIBTRACE_H
36
37/** @file
38 *
39 * @brief Trace file processing library header
40 *
41 * @author Daniel Lawson
42 * @author Perry Lorier
43 * @author Shane Alcock
44 *
45 * @version $Id$
46 *
47 * This library provides a per packet interface into a trace file, or a live
48 * captures.  It supports ERF, DAG cards, PCAP, Linux and BSD native sockets,
49 * legacy ERF formats etc.
50 *
51 * @par Usage
52 * See the example/ directory in the source distribution for some simple
53 * examples
54 *
55 * @par Linking
56 * To use this library you need to link against libtrace by passing -ltrace
57 * to your linker. You may also need to link against a version of libpcap
58 * and of zlib which are compiled for largefile support (if you wish to access
59 * traces larger than 2 GB). This is left as an exercise for the reader. Debian
60 * Woody, at least, does not support large file offsets.
61 *
62 */
63
64#include <sys/types.h>
65#ifndef WIN32
66#include <sys/time.h>
67#endif
68
69#ifdef _MSC_VER
70    /* define the following from MSVC's internal types */
71    typedef             __int8  int8_t;
72    typedef             __int16 int16_t;
73    typedef             __int32 int32_t;
74    typedef             __int64 int64_t;
75    typedef unsigned    __int8  uint8_t;
76    typedef unsigned    __int16 uint16_t;
77    typedef unsigned    __int32 uint32_t;
78    typedef unsigned    __int64 uint64_t;
79    #ifdef LT_BUILDING_DLL
80        #define DLLEXPORT __declspec(dllexport)
81    #else
82        #define DLLEXPORT __declspec(dllimport)
83    #endif
84    #define DLLLOCAL
85    /* Windows pads bitfields out to to the size of their parent type
86     * however gcc warns that this doesn't meet with the iso C specification
87     * so produces warnings for this behaviour.  sigh.
88     */
89    #define LT_BITFIELD8        uint8_t
90    #define LT_BITFIELD16       uint16_t
91    #define LT_BITFIELD32       uint32_t
92    #define LT_BITFIELD64       uint64_t
93#else
94    #ifdef HAVE_STDINT_H
95        #   include <stdint.h>
96    #endif
97    #if __GNUC__ >= 4
98        #ifdef LT_BUILDING_DLL
99                #define DLLEXPORT __attribute__ ((visibility("default")))
100                #define DLLLOCAL __attribute__ ((visibility("hidden")))
101        #else
102                #define DLLEXPORT
103                #define DLLLOCAL
104        #endif
105    #else
106        #define DLLEXPORT
107        #define DLLLOCAL
108    #endif
109    /* GCC warns if the bitfield type is not "unsigned int", however windows
110     * generates incorrect code for this (see above), so we define these
111     * macros.  How Hideous.  So much for C's portability.
112     */
113    #define LT_BITFIELD8        unsigned int
114    #define LT_BITFIELD16       unsigned int
115    #define LT_BITFIELD32       unsigned int
116    #define LT_BITFIELD64       unsigned int
117#endif
118
119#ifdef WIN32
120#   include <winsock2.h>
121#   include <ws2tcpip.h>
122    typedef short sa_family_t;
123    /* Make up for a lack of stdbool.h */
124#    define bool signed char
125#    define false 0
126#    define true 1
127#    if !defined(ssize_t)
128     /* XXX: Not 64-bit safe! */
129#    define ssize_t int
130#    endif   
131#else
132#    include <netinet/in.h>
133
134#ifndef __cplusplus
135#    include <stdbool.h>
136#endif
137
138#    include <sys/types.h>
139#    include <sys/socket.h>
140#endif
141
142/** API version as 2 byte hex digits, eg 0xXXYYZZ */
143#define LIBTRACE_API_VERSION \
144            ((@LIBTRACE_MAJOR@<<16)|(@LIBTRACE_MID@<<8)|(@LIBTRACE_MINOR@))
145
146/** Replaced with the current SVN revision number when 'make dist' is invoked
147 *  to create a distributable tarball */
148#define LIBTRACE_SVN_REVISION 0
149
150/** DAG driver version installed on the current system */
151#define DAG_DRIVER_V "@DAG_VERSION_NUM@"
152   
153#ifdef __cplusplus
154extern "C" {
155#endif
156
157/* Function does not depend on anything but its
158 * parameters, used to hint gcc's optimisations
159 */
160#if __GNUC__ >= 3
161#  define DEPRECATED __attribute__((deprecated))
162#  define SIMPLE_FUNCTION __attribute__((pure))
163#  define UNUSED __attribute__((unused))
164#  define PACKED __attribute__((packed))
165#  define PRINTF(formatpos,argpos) __attribute__((format(printf,formatpos,argpos)))
166#else
167#  define DEPRECATED
168#  define SIMPLE_FUNCTION
169#  define UNUSED
170#  define PACKED
171#  define PRINTF(formatpos,argpos)
172#endif
173       
174/** Opaque structure holding information about an output trace */
175typedef struct libtrace_out_t libtrace_out_t;
176       
177/** Opaque structure holding information about a trace */
178typedef struct libtrace_t libtrace_t;
179       
180/** Opaque structure holding information about a bpf filter */
181typedef struct libtrace_filter_t libtrace_filter_t;
182
183/** If the packet has allocated its own memory the buffer_control should be
184 * set to TRACE_CTRL_PACKET, so that the memory will be freed when the packet
185 * is destroyed. If the packet has been zerocopied out of memory owned by
186 * something else, e.g. a DAG card, it should be TRACE_CTRL_EXTERNAL.
187 *
188 * @note The letters p and e are magic numbers used to detect if the packet
189 * wasn't created properly.
190 */
191typedef enum {
192        TRACE_CTRL_PACKET='p',  /**< Buffer memory is owned by the packet */
193        TRACE_CTRL_EXTERNAL='e' /**< Buffer memory is owned by an external source */
194} buf_control_t;
195
196/** The size of a packet's buffer when managed by libtrace */
197#define LIBTRACE_PACKET_BUFSIZE 65536
198
199/** Libtrace error information */
200typedef struct trace_err_t{
201        int err_num;            /**< error code */
202        char problem[255];      /**< the format, uri etc that caused the error for reporting purposes */
203} libtrace_err_t;
204
205/** Enumeration of error codes */
206enum {
207        /** No Error has occured.... yet. */
208        TRACE_ERR_NOERROR       = 0,
209        /** The URI passed to trace_create() is unsupported, or badly formed */
210        TRACE_ERR_BAD_FORMAT    = -1,
211        /** The trace failed to initialise */
212        TRACE_ERR_INIT_FAILED   = -2,
213        /** Unknown config option */
214        TRACE_ERR_UNKNOWN_OPTION= -3,
215        /** This output uri cannot write packets of this type */
216        TRACE_ERR_NO_CONVERSION = -4,
217        /** This packet is corrupt, or unusable for the action required */
218        TRACE_ERR_BAD_PACKET    = -5,
219        /** Option known, but unsupported by this format */
220        TRACE_ERR_OPTION_UNAVAIL= -6,
221        /** This feature is unsupported */
222        TRACE_ERR_UNSUPPORTED   = -7,
223        /** Illegal use of the API */
224        TRACE_ERR_BAD_STATE     = -8
225};
226
227/** Enumeration of DLTs supported by libtrace
228 */
229typedef enum {
230        /** pcap documents this as having the Address Family value in host byte order as the
231          * framing.  Ugly? Yes.
232          */
233        TRACE_DLT_NULL = 0,
234        TRACE_DLT_EN10MB = 1,
235        TRACE_DLT_PPP = 9,
236        TRACE_DLT_ATM_RFC1483 = 11,
237       
238        /** Ok, so OpenBSD has a different value for DLT_RAW as the rest of the planet, so detect
239          * this.  When reading to/from files we should be using TRACE_DLT_LINKTYPE_RAW instead.
240          * When talking about DLT's inside libtrace tho, we should be using /these/ DLT's.
241          */
242#ifdef __OpenBSD__
243        TRACE_DLT_RAW = 14,     
244#else
245        TRACE_DLT_RAW = 12,
246#endif
247        TRACE_DLT_PPP_SERIAL = 50,
248        TRACE_DLT_LINKTYPE_RAW = 101, /**< See TRACE_DLT_RAW for explainations of pain. */
249        TRACE_DLT_C_HDLC = 104,
250        TRACE_DLT_IEEE802_11 = 105,
251        TRACE_DLT_LINUX_SLL = 113,
252        TRACE_DLT_PFLOG = 117,
253        TRACE_DLT_IEEE802_11_RADIO = 127 /**< Radiotap */
254} libtrace_dlt_t ;
255
256/** Enumeration of link layer types supported by libtrace */
257typedef enum {
258    /* TRACE_TYPE_LEGACY = 0            Obsolete */
259       TRACE_TYPE_HDLC_POS = 1,         /**< HDLC over POS */
260       TRACE_TYPE_ETH = 2,              /**< 802.3 style Ethernet */
261       TRACE_TYPE_ATM = 3,              /**< ATM frame */
262       TRACE_TYPE_80211 = 4,            /**< 802.11 frames */
263       TRACE_TYPE_NONE = 5,             /**< Raw IP frames */
264       TRACE_TYPE_LINUX_SLL = 6,        /**< Linux "null" framing */
265       TRACE_TYPE_PFLOG = 7,            /**< FreeBSD's PFlog */
266    /* TRACE_TYPE_LEGACY_DEFAULT        Obsolete */
267       TRACE_TYPE_POS = 9,              /**< Packet-over-SONET */
268    /* TRACE_TYPE_LEGACY_ATM            Obsolete */
269    /* TRACE_TYPE_LEGACY_ETH            Obsolete */
270       TRACE_TYPE_80211_PRISM = 12,     /**< 802.11 Prism frames */
271       TRACE_TYPE_AAL5 = 13,            /**< ATM Adaptation Layer 5 frames */
272       TRACE_TYPE_DUCK = 14,         /**< Pseudo link layer for DUCK packets */
273       TRACE_TYPE_80211_RADIO = 15,  /**< Radiotap + 802.11 */
274       TRACE_TYPE_LLCSNAP = 16,      /**< Raw LLC/SNAP */
275       TRACE_TYPE_PPP = 17,          /**< PPP frames */
276       TRACE_TYPE_METADATA = 18,        /**< WDCAP-style meta-data */
277       TRACE_TYPE_NONDATA = 19          /**< Not a data packet */
278} libtrace_linktype_t;
279
280/** RT protocol base format identifiers.
281 * This is used to describe the capture format of the packet is being sent
282 * using the RT protocol.
283 */
284enum base_format_t {
285        TRACE_FORMAT_ERF          =1,   /**< ERF (DAG capture format) */
286        TRACE_FORMAT_PCAP         =2,   /**< Live PCAP capture */
287        TRACE_FORMAT_PCAPFILE     =3,   /**< PCAP trace file */
288        TRACE_FORMAT_WAG          =4,   /**< WAG live capture (Obsolete) */
289        TRACE_FORMAT_RT           =5,   /**< RT network protocol */
290        TRACE_FORMAT_LEGACY_ATM   =6,   /**< Legacy ERF for ATM capture */
291        TRACE_FORMAT_LEGACY_POS   =7,   /**< Legacy ERF for POS capture */
292        TRACE_FORMAT_LEGACY_ETH   =8,   /**< Legacy ERF for ETH capture */
293        TRACE_FORMAT_LINUX_NATIVE =9,   /**< Linux native interface capture */
294        TRACE_FORMAT_DUCK         =10,  /**< DAG Clock information */
295        TRACE_FORMAT_BPF          =11,  /**< BSD native interface capture */
296        TRACE_FORMAT_TSH          =12,  /**< TSH trace format */
297        TRACE_FORMAT_ATMHDR       =13,  /**< Legacy ATM header capture */
298        TRACE_FORMAT_LEGACY_NZIX  =14   /**< Legacy format used for NZIX traces */
299};
300
301/** RT protocol packet types */
302typedef enum {
303        TRACE_RT_HELLO          =1, /**< Connection accepted */
304        TRACE_RT_START          =2, /**< Request for data transmission to begin
305                                    */
306        TRACE_RT_ACK            =3, /**< Data acknowledgement */
307        TRACE_RT_STATUS         =4, /**< Fifo status packet */
308        TRACE_RT_DUCK           =5, /**< Dag duck info packet */
309        TRACE_RT_END_DATA       =6, /**< Server is exiting message */
310        TRACE_RT_CLOSE          =7, /**< Client is exiting message */
311        TRACE_RT_DENY_CONN      =8, /**< Connection has been denied */
312        TRACE_RT_PAUSE          =9, /**< Request server to suspend sending data
313                                     */
314        TRACE_RT_PAUSE_ACK      =10,/**< Server is paused message */
315        TRACE_RT_OPTION         =11,/**< Option request */
316        TRACE_RT_KEYCHANGE      =12,/**< Anonymisation key has changed */
317        TRACE_RT_DUCK_2_4       =13,/**< Dag 2.4 Duck */
318        TRACE_RT_DUCK_2_5       =14,/**< Dag 2.5 Duck */
319        TRACE_RT_LOSTCONN       =15,/**< Lost connection to server */
320        TRACE_RT_SERVERSTART    =16,/**< Reliable server has been restarted */
321        TRACE_RT_CLIENTDROP     =17,/**< Reliable client was lost */
322        TRACE_RT_METADATA       =18,/**< Packet contains server meta-data */
323
324        /** Not actually used - all DATA types begin from this value */
325        TRACE_RT_DATA_SIMPLE    = 1000,
326       
327        /** RT is encapsulating an ERF capture record */
328        TRACE_RT_DATA_ERF       =TRACE_RT_DATA_SIMPLE+TRACE_FORMAT_ERF,
329        /** RT is encapsulating a WAG capture record */
330        TRACE_RT_DATA_WAG       =TRACE_RT_DATA_SIMPLE+TRACE_FORMAT_WAG,
331        /** RT is encapsulating a Legacy ATM capture record */
332        TRACE_RT_DATA_LEGACY_ATM=TRACE_RT_DATA_SIMPLE+TRACE_FORMAT_LEGACY_ATM,
333        /** RT is encapsulating a Legacy POS capture record */
334        TRACE_RT_DATA_LEGACY_POS=TRACE_RT_DATA_SIMPLE+TRACE_FORMAT_LEGACY_POS,
335        /** RT is encapsulating a Legacy ETH capture record */
336        TRACE_RT_DATA_LEGACY_ETH=TRACE_RT_DATA_SIMPLE+TRACE_FORMAT_LEGACY_ETH,
337        /** RT is encapsulating a Linux native capture record */
338        TRACE_RT_DATA_LINUX_NATIVE=TRACE_RT_DATA_SIMPLE+TRACE_FORMAT_LINUX_NATIVE,
339        /** RT is encapsulating a BSD native capture record */
340        TRACE_RT_DATA_BPF       =TRACE_RT_DATA_SIMPLE+TRACE_FORMAT_BPF,
341        /** RT is encapsulating a TSH capture record */
342        TRACE_RT_DATA_TSH       =TRACE_RT_DATA_SIMPLE+TRACE_FORMAT_TSH,
343        /** RT is encapsulating an ATM header capture record */
344        TRACE_RT_DATA_ATMHDR = TRACE_RT_DATA_SIMPLE + TRACE_FORMAT_ATMHDR,
345        /** RT is encapsulating a Legacy NZIX capture record */
346        TRACE_RT_DATA_LEGACY_NZIX=TRACE_RT_DATA_SIMPLE + TRACE_FORMAT_LEGACY_NZIX,
347
348        /** As PCAP does not store the linktype with the packet, we need to
349         * create a separate RT type for each supported DLT, starting from
350         * this value */
351        TRACE_RT_DATA_DLT               = 2000,
352        /** RT is encapsulating a PCAP capture record with a NULL linktype */
353        TRACE_RT_DLT_NULL               =TRACE_RT_DATA_DLT+TRACE_DLT_NULL,
354        /** RT is encapsulating a PCAP capture record with an Ethernet
355         * linktype */
356        TRACE_RT_DLT_EN10MB             =TRACE_RT_DATA_DLT+TRACE_DLT_EN10MB,
357        /** RT is encapsulating a PCAP capture record with an 802.11
358         * linktype */
359        TRACE_RT_DLT_IEEE802_11         =TRACE_RT_DATA_DLT+TRACE_DLT_IEEE802_11,
360        /** RT is encapsulating a PCAP capture record with a Linux SLL
361         * linktype */
362        TRACE_RT_DLT_LINUX_SLL          =TRACE_RT_DATA_DLT+TRACE_DLT_LINUX_SLL,
363        /** RT is encapsulating a PCAP capture record with a PFlog linktype */
364        TRACE_RT_DLT_PFLOG              =TRACE_RT_DATA_DLT+TRACE_DLT_PFLOG,
365        /** RT is encapsulating a PCAP capture record with an AAL5 linktype */
366        TRACE_RT_DLT_ATM_RFC1483        =TRACE_RT_DATA_DLT+TRACE_DLT_ATM_RFC1483,
367        /** Unused value marking the end of the valid range for PCAP RT
368         * encapsulation */
369        TRACE_RT_DATA_DLT_END           = 2999,
370        /** Unused value marking the end of the valid range for all RT packet
371         * types */
372        TRACE_RT_LAST                   = (2<<31)
373} libtrace_rt_types_t;
374
375/** IP Protocol values */
376typedef enum {
377        TRACE_IPPROTO_IP        = 0,    /**< IP pseudo protocol number */
378        TRACE_IPPROTO_ICMP      = 1,    /**< Internet Control Message protocol */
379        TRACE_IPPROTO_IGMP      = 2,    /**< Internet Group Management Protocol */
380        TRACE_IPPROTO_IPIP      = 4,    /**< IP encapsulated in IP */
381        TRACE_IPPROTO_TCP       = 6,    /**< Transmission Control Protocol */
382        TRACE_IPPROTO_UDP       = 17,   /**< User Datagram Protocol */
383        TRACE_IPPROTO_IPV6      = 41,   /**< IPv6 over IPv4 */
384        TRACE_IPPROTO_ROUTING   = 43,   /**< IPv6 Routing header */
385        TRACE_IPPROTO_FRAGMENT  = 44,   /**< IPv6 Fragmentation header */
386        TRACE_IPPROTO_RSVP      = 46,   /**< Resource Reservation Protocol */
387        TRACE_IPPROTO_GRE       = 47,   /**< General Routing Encapsulation */
388        TRACE_IPPROTO_ESP       = 50,   /**< Encapsulated Security Payload [RFC2406] */
389        TRACE_IPPROTO_AH        = 51,   /**< Authentication Header [RFC2402] */
390        TRACE_IPPROTO_ICMPV6    = 58,   /**< ICMPv6 */
391        TRACE_IPPROTO_NONE      = 59,   /**< IPv6 no next header */
392        TRACE_IPPROTO_DSTOPTS   = 60,   /**< IPv6 destination options */
393        TRACE_IPPROTO_PIM       = 103,  /**< Protocol Independant Multicast */
394        TRACE_IPPROTO_SCTP      = 132   /**< Stream Control Transmission Protocol */
395} libtrace_ipproto_t;
396
397/** Ethertypes supported by Libtrace */
398typedef enum {
399        /* Numbers <=1500 are of course, LLC/SNAP */
400        TRACE_ETHERTYPE_IP      = 0x0800,       /**< IPv4 */
401        TRACE_ETHERTYPE_ARP     = 0x0806,       /**< Address resolution protocol */
402        TRACE_ETHERTYPE_RARP    = 0x8035,       /**< Reverse ARP */
403        TRACE_ETHERTYPE_8021Q   = 0x8100,       /**< 802.1q VLAN Extended Header */
404        TRACE_ETHERTYPE_IPV6    = 0x86DD,       /**< IPv6 */
405        TRACE_ETHERTYPE_MPLS    = 0x8847,       /**< MPLS Unicast traffic */
406        TRACE_ETHERTYPE_MPLS_MC = 0x8848,       /**< MPLS Multicast traffic */
407        TRACE_ETHERTYPE_PPP_DISC= 0x8863,       /**< PPPoE Service Discovery */
408        TRACE_ETHERTYPE_PPP_SES = 0x8864        /**< PPPoE Session Messages */
409} libtrace_ethertype_t;
410
411/** The libtrace packet structure. Applications shouldn't be
412 * meddling around in here
413 */
414typedef struct libtrace_packet_t {
415        struct libtrace_t *trace;       /**< Pointer to the trace */
416        void *header;                   /**< Pointer to the framing header */
417        void *payload;                  /**< Pointer to the link layer */
418        void *buffer;                   /**< Allocated buffer */
419        libtrace_rt_types_t  type;      /**< RT protocol type for the packet */
420        buf_control_t buf_control;      /**< Describes memory ownership */
421        int capture_length;             /**< Cached capture length */
422        int payload_length;             /**< Cached payload length */
423        void *l3_header;                /**< Cached l3 header */
424        uint16_t l3_ethertype;          /**< Cached l3 ethertype */
425        void *l4_header;                /**< Cached transport header */
426        uint8_t transport_proto;        /**< Cached transport protocol */
427} libtrace_packet_t;
428
429
430/** Trace directions.
431 * Note that these are the directions used by convention. More directions
432 * are possible, not just these 3, and that they may not conform to this
433 * convention.
434 */
435typedef enum {
436        TRACE_DIR_OUTGOING = 0,         /**< Packets originating "inside" */
437        TRACE_DIR_INCOMING = 1,         /**< Packets originating "outside" */
438        TRACE_DIR_OTHER    = 2          /**< Packets with an unknown direction, or one that's unknown */
439} libtrace_direction_t;
440
441/** Enumeration of Radiotap fields */
442typedef enum {
443    TRACE_RADIOTAP_TSFT = 0, /**< Timer synchronisation function, in microseconds (uint64) */
444    TRACE_RADIOTAP_FLAGS = 1, /**< Wireless flags (uint8) */
445    TRACE_RADIOTAP_RATE = 2, /**< Bitrate in units of 500kbps (uint8) */
446    TRACE_RADIOTAP_CHANNEL = 3, /**< Frequency in MHz (uint16) and channel flags (uint16) */
447    TRACE_RADIOTAP_FHSS = 4, /**< FHSS hop set (uint8) and hopping pattern (uint8) */
448    TRACE_RADIOTAP_DBM_ANTSIGNAL = 5, /**< Signal power in dBm (int8) */
449    TRACE_RADIOTAP_DBM_ANTNOISE = 6, /**< Noise power in dBm (int8) */
450    TRACE_RADIOTAP_LOCK_QUALITY = 7, /**< Barker Code lock quality (uint16) */
451    TRACE_RADIOTAP_TX_ATTENUATION = 8, /**< TX attenuation as unitless distance from max power (uint16) */
452    TRACE_RADIOTAP_DB_TX_ATTENUATION = 9, /**< TX attenutation as dB from max power (uint16) */
453    TRACE_RADIOTAP_DBM_TX_POWER = 10, /**< TX Power in dBm (int8) */
454    TRACE_RADIOTAP_ANTENNA = 11, /**< Antenna frame was rx'd or tx'd on (uint8) */
455    TRACE_RADIOTAP_DB_ANTSIGNAL = 12, /**< Signal power in dB from a fixed reference (uint8) */
456    TRACE_RADIOTAP_DB_ANTNOISE = 13, /**< Noise power in dB from a fixed reference (uint8) */
457    TRACE_RADIOTAP_RX_FLAGS = 14, /** Properties of received frame (uint16) */
458    TRACE_RADIOTAP_TX_FLAGS = 15, /** Properties of transmitted frame (uint16) */
459    TRACE_RADIOTAP_RTS_RETRIES = 16, /** Number of rts retries frame used (uint8) */
460    TRACE_RADIOTAP_DATA_RETRIES = 17, /** Number of unicast retries a transmitted frame used (uint8) */
461    TRACE_RADIOTAP_EXT = 31
462} libtrace_radiotap_field_t;
463
464
465/** @name Protocol structures
466 * These convenience structures provide portable versions of the headers
467 * for a variety of protocols.
468 * @{
469 */
470
471#ifdef WIN32
472#pragma pack(push)
473#pragma pack(1)
474#endif
475
476/** Generic IP header structure */
477typedef struct libtrace_ip
478{
479#if BYTE_ORDER == LITTLE_ENDIAN
480    LT_BITFIELD8 ip_hl:4;               /**< Header Length */
481    LT_BITFIELD8 ip_v:4;                /**< Version */
482#elif BYTE_ORDER == BIG_ENDIAN
483    LT_BITFIELD8 ip_v:4;                /**< Version */
484    LT_BITFIELD8 ip_hl:4;               /**< Header Length */
485#else
486#   error "Adjust your <bits/endian.h> defines"
487#endif
488    uint8_t  ip_tos;                    /**< Type of Service */
489    uint16_t ip_len;                    /**< Total Length */
490    int16_t  ip_id;                     /**< Identification */
491    uint16_t ip_off;                    /**< IP Fragment offset (and flags) */
492    uint8_t  ip_ttl;                    /**< Time to Live */
493    uint8_t  ip_p;                      /**< Protocol */
494    uint16_t ip_sum;                    /**< Checksum */
495    struct in_addr ip_src;              /**< Source Address */
496    struct in_addr ip_dst;              /**< Destination Address */
497} PACKED libtrace_ip_t;
498
499/** IPv6 header extension structure */
500typedef struct libtrace_ip6_ext
501{
502        uint8_t nxt;    /**< Next header */
503        uint8_t len;    /**< Length of the current header */
504} PACKED libtrace_ip6_ext_t;
505
506typedef struct libtrace_ip6_frag
507{
508        uint8_t nxt;    /**< Next header */
509        uint8_t res;    /**< Reserved */
510        uint16_t frag_off;      /**< Fragment Offset (includes M flag) */
511        uint32_t ident; /** Fragment identification */
512} PACKED libtrace_ip6_frag_t;
513
514/** Generic IPv6 header structure
515 *
516 * @note The flow label field also includes the Version and Traffic Class
517 * fields, because we haven't figured out a nice way to deal with fields
518 * crossing byte boundaries on both Big and Little Endian machines */
519typedef struct libtrace_ip6
520{
521    uint32_t flow;                      /**< Flow label */
522    uint16_t plen;                      /**< Payload length */
523    uint8_t nxt;                        /**< Next header */
524    uint8_t hlim;                       /**< Hop limit */
525    struct in6_addr ip_src;             /**< Source address */
526    struct in6_addr ip_dst;             /**< Destination address */
527} PACKED libtrace_ip6_t;
528
529/** Generic TCP header structure */
530typedef struct libtrace_tcp
531  {
532    uint16_t source;            /**< Source Port */
533    uint16_t dest;              /**< Destination port */
534    uint32_t seq;               /**< Sequence number */
535    uint32_t ack_seq;           /**< Acknowledgement Number */
536#  if BYTE_ORDER == LITTLE_ENDIAN
537    LT_BITFIELD8 res1:4;        /**< Reserved bits */
538    LT_BITFIELD8 doff:4;        /**< Data Offset */     
539    LT_BITFIELD8 fin:1;         /**< FIN */
540    LT_BITFIELD8 syn:1;         /**< SYN flag */
541    LT_BITFIELD8 rst:1;         /**< RST flag */
542    LT_BITFIELD8 psh:1;         /**< PuSH flag */
543    LT_BITFIELD8 ack:1;         /**< ACK flag */
544    LT_BITFIELD8 urg:1;         /**< URG flag */
545    LT_BITFIELD8 res2:2;        /**< Reserved */
546#  elif BYTE_ORDER == BIG_ENDIAN
547    LT_BITFIELD8 doff:4;        /**< Data offset */
548    LT_BITFIELD8 res1:4;        /**< Reserved bits */
549    LT_BITFIELD8 res2:2;        /**< Reserved */
550    LT_BITFIELD8 urg:1;         /**< URG flag */
551    LT_BITFIELD8 ack:1;         /**< ACK flag */
552    LT_BITFIELD8 psh:1;         /**< PuSH flag */
553    LT_BITFIELD8 rst:1;         /**< RST flag */
554    LT_BITFIELD8 syn:1;         /**< SYN flag */
555    LT_BITFIELD8 fin:1;         /**< FIN flag */
556#  else
557#   error "Adjust your <bits/endian.h> defines"
558#  endif
559    uint16_t window;            /**< Window Size */
560    uint16_t check;             /**< Checksum */
561    uint16_t urg_ptr;           /**< Urgent Pointer */
562} PACKED libtrace_tcp_t;
563
564/** Generic UDP header structure */
565typedef struct libtrace_udp {
566  uint16_t      source;         /**< Source port */
567  uint16_t      dest;           /**< Destination port */
568  uint16_t      len;            /**< Length */
569  uint16_t      check;          /**< Checksum */
570} PACKED libtrace_udp_t;
571
572/** Generic ICMP header structure */
573typedef struct libtrace_icmp
574{
575  uint8_t type;         /**< Message Type */
576  uint8_t code;         /**< Type Sub-code */
577  uint16_t checksum;            /**< Checksum */
578  union
579  {
580    struct
581    {
582      uint16_t  id;             /**< ID of the Echo request */
583      uint16_t  sequence;       /**< Sequence number of the Echo request */
584    } echo;                     /**< Echo Datagram */
585    uint32_t    gateway;        /**< Gateway Address */
586    struct
587    {
588      uint16_t  unused;         /**< Unused */
589      uint16_t  mtu;            /**< Next-hop MTU */
590    } frag;                     /**< Path MTU Discovery */
591  } un;                         /**< Union for Payloads of Various ICMP Codes */
592} PACKED libtrace_icmp_t;
593
594/** Generic LLC/SNAP header structure */
595typedef struct libtrace_llcsnap
596{
597/* LLC */
598  uint8_t dsap;                 /**< Destination Service Access Point */
599  uint8_t ssap;                 /**< Source Service Access Point */
600  uint8_t control;              /**< Control field */
601/* SNAP */
602  LT_BITFIELD32 oui:24;         /**< Organisationally Unique Identifier (scope)*/
603  uint16_t type;                /**< Protocol within OUI */
604} PACKED libtrace_llcsnap_t;
605
606/** 802.3 frame */
607typedef struct libtrace_ether
608{
609  uint8_t ether_dhost[6];       /**< Destination Ether Addr */
610  uint8_t ether_shost[6];       /**< Source Ether Addr */
611  uint16_t ether_type;          /**< Packet Type ID Field (next-header) */
612} PACKED libtrace_ether_t;
613
614/** 802.1Q frame */
615typedef struct libtrace_8021q
616{
617  LT_BITFIELD16 vlan_pri:3;      /**< VLAN User Priority */
618  LT_BITFIELD16 vlan_cfi:1;      /**< VLAN Format Indicator,
619                                   * 0 for ethernet, 1 for token ring */
620  LT_BITFIELD16 vlan_id:12;      /**< VLAN Id */
621  uint16_t vlan_ether_type;      /**< VLAN Sub-packet Type ID Field
622                                   * (next-header)*/
623} PACKED libtrace_8021q_t;
624
625/** ATM User Network Interface (UNI) Cell. */
626typedef struct libtrace_atm_cell
627{
628  LT_BITFIELD32 gfc:4;          /**< Generic Flow Control */
629  LT_BITFIELD32 vpi:8;          /**< Virtual Path Identifier */
630  LT_BITFIELD32 vci:16;         /**< Virtual Channel Identifier */
631  LT_BITFIELD32 pt:3;           /**< Payload Type */
632  LT_BITFIELD32 clp:1;          /**< Cell Loss Priority */
633  LT_BITFIELD32 hec:8;          /**< Header Error Control */
634} PACKED libtrace_atm_cell_t;
635
636/** ATM Network Node/Network Interface (NNI) Cell. */
637typedef struct libtrace_atm_nni_cell
638{
639  LT_BITFIELD32 vpi:12;         /**< Virtual Path Identifier */
640  LT_BITFIELD32 vci:16;         /**< Virtual Channel Identifier */
641  LT_BITFIELD32 pt:3;           /**< Payload Type */
642  LT_BITFIELD32 clp:1;          /**< Cell Loss Priority */
643  LT_BITFIELD32 hec:8;          /**< Header Error Control */
644} PACKED libtrace_atm_nni_cell_t;
645
646/** Captured UNI cell.
647 *
648 * Endace don't capture the HEC, presumably to keep alignment.  This
649 * version of the \ref libtrace_atm_cell is used when dealing with DAG
650 * captures of uni cells.
651 *
652 */
653typedef struct libtrace_atm_capture_cell
654{
655  LT_BITFIELD32 gfc:4;          /**< Generic Flow Control */
656  LT_BITFIELD32 vpi:8;          /**< Virtual Path Identifier */
657  LT_BITFIELD32 vci:16;         /**< Virtual Channel Identifier */
658  LT_BITFIELD32 pt:3;           /**< Payload Type */
659  LT_BITFIELD32 clp:1;          /**< Cell Loss Priority */
660} PACKED libtrace_atm_capture_cell_t;
661
662/** Captured NNI cell.
663 *
664 * Endace don't capture the HEC, presumably to keep alignment.  This
665 * version of the \ref libtrace_atm_nni_cell is used when dealing with DAG
666 * captures of nni cells.
667 *
668 */
669typedef struct libtrace_atm_nni_capture_cell
670{
671  LT_BITFIELD32 vpi:12;         /**< Virtual Path Identifier */
672  LT_BITFIELD32 vci:16;         /**< Virtual Channel Identifier */
673  LT_BITFIELD32 pt:3;           /**< Payload Type */
674  LT_BITFIELD32 clp:1;          /**< Cell Loss Priority */
675  LT_BITFIELD32 hec:8;          /**< Header Error Control */
676} PACKED libtrace_atm_nni_capture_cell_t;
677
678/** PPP header */
679typedef struct libtrace_ppp
680{
681 /* I can't figure out where the hell these two variables come from. They're
682  * definitely not in RFC 1661 which defines PPP. Probably some weird thing
683  * relating to the lack of distinction between PPP, HDLC and CHDLC */
684       
685/* uint8_t address; */          /**< PPP Address (0xFF - All stations) */
686/* uint8_t header;  */          /**< PPP Control (0x03 - Unnumbered info) */
687 uint16_t protocol;             /**< PPP Protocol (htons(0x0021) - IPv4 */
688} PACKED libtrace_ppp_t;
689
690/** PPPoE header */
691typedef struct libtrace_pppoe
692{
693 LT_BITFIELD8 version:4;        /**< Protocol version number */
694 LT_BITFIELD8 type:4;           /**< PPPoE Type */
695 uint8_t code;                  /**< PPPoE Code */
696 uint16_t session_id;           /**< Session Identifier */
697 uint16_t length;               /**< Total Length of the PPP packet */
698} PACKED libtrace_pppoe_t;
699
700/** 802.11 header */
701typedef struct libtrace_80211_t {
702#if BYTE_ORDER == LITTLE_ENDIAN
703        LT_BITFIELD32      protocol:2;  /**< Protocol Version */
704        LT_BITFIELD32      type:2;      /**< Frame Type */
705        LT_BITFIELD32      subtype:4;   /**< Frame Subtype */
706#else
707        LT_BITFIELD32      subtype:4;   /**< Frame Subtype */
708        LT_BITFIELD32      type:2;      /**< Frame Type */
709        LT_BITFIELD32      protocol:2;  /**< Protocol Version */
710#endif
711
712#if BYTE_ORDER == LITTLE_ENDIAN
713        LT_BITFIELD32      to_ds:1;     /**< Packet to Distribution Service */
714        LT_BITFIELD32      from_ds:1;   /**< Packet from Distribution Service */
715        LT_BITFIELD32      more_frag:1; /**< Packet has more fragments */
716        LT_BITFIELD32      retry:1;     /**< Packet is a retry */
717        LT_BITFIELD32      power:1;     /**< Power Management mode */
718        LT_BITFIELD32      more_data:1; /**< More data is buffered at station */
719        LT_BITFIELD32      wep:1;       /**< WEP encryption indicator */
720        LT_BITFIELD32      order:1;     /**< Strictly-Ordered class indicator */
721#else
722        LT_BITFIELD32      order:1;     /**< Strictly-Ordered class indicator */
723        LT_BITFIELD32      wep:1;       /**< WEP encryption indicator */
724        LT_BITFIELD32      more_data:1; /**< More data is buffered at station */
725        LT_BITFIELD32      power:1;     /**< Power Management mode */
726        LT_BITFIELD32      retry:1;     /**< Packet is a retry */
727        LT_BITFIELD32      more_frag:1; /**< Packet has more fragments */
728        LT_BITFIELD32      from_ds:1;   /**< Packet from Distribution Service */
729        LT_BITFIELD32      to_ds:1;     /**< Packet to Distribution Service */
730#endif
731        uint16_t     duration;  /**< Duration value for NAV calculation */
732        uint8_t      mac1[6];   /**< MAC Address 1 */
733        uint8_t      mac2[6];   /**< MAC Address 2 */
734        uint8_t      mac3[6];   /**< MAC Address 3 */
735        uint16_t     SeqCtl;    /**< Sequence Control */       
736        uint8_t      mac4[6];   /**< MAC Address 4 */
737} PACKED libtrace_80211_t;
738
739/** The Radiotap header pre-amble
740 *
741 * All Radiotap headers start with this pre-amble, followed by the fields
742 * specified in the it_present bitmask. If bit 31 of it_present is set, then
743 * another bitmask follows.
744 * @note All of the radiotap data fields are in little-endian byte-order.
745 */
746typedef struct libtrace_radiotap_t {
747    uint8_t     it_version; /**< Radiotap version */
748    uint8_t     it_pad; /**< Padding for natural alignment */
749    uint16_t    it_len; /**< Length in bytes of the entire Radiotap header */
750    uint32_t    it_present; /**< Which Radiotap fields are present */
751} PACKED libtrace_radiotap_t;
752
753
754#ifdef WIN32
755#pragma pack(pop)
756#endif
757
758
759/*@}*/
760
761/** Prints help information for libtrace
762 *
763 * Function prints out some basic help information regarding libtrace,
764 * and then prints out the help() function registered with each input module
765 */
766DLLEXPORT void trace_help(void);
767
768/** @name Trace management
769 * These members deal with creating, configuring, starting, pausing and
770 * cleaning up a trace object
771 *@{
772 */
773
774/** Takes a uri and splits it into a format and uridata component.
775 * @param uri           The uri to be parsed
776 * @param [out] format  A pointer that will be updated to point to an allocated
777 *                      string holding the format component of the URI
778 * @return NULL if an error occured, otherwise return a pointer to the uridata
779 * component
780 *
781 * @note The format component is strdup'd by this function, so be sure to free
782 * it when you are done with the split URI. Similarly, do not pass a pointer
783 * to an allocated string into this function as the 'format' parameter, as
784 * that memory will be leaked and replaced with the strdup'd format.
785 */
786DLLEXPORT const char *trace_parse_uri(const char *uri, char **format);
787
788/** Create an input trace from a URI
789 *
790 * @param uri A valid libtrace URI to be opened
791 * @return An opaque pointer to a libtrace_t
792 *
793 * Some valid URI's are:
794 *  - erf:/path/to/erf/file
795 *  - erf:-  (stdin)
796 *  - dag:/dev/dagcard                 
797 *  - pcapint:pcapinterface                (eg: pcap:eth0)
798 *  - pcap:/path/to/pcap/file
799 *  - pcap:-
800 *  - rt:hostname
801 *  - rt:hostname:port
802 *
803 *  If an error occured when attempting to open the trace file, a
804 *  trace is still returned so trace_is_err() should be called to find out
805 *  if an error occured. The trace is created in the configuration state, you
806 *  must call trace_start before attempting to read packets from the trace.
807 */
808DLLEXPORT libtrace_t *trace_create(const char *uri);
809
810/** Creates a "dummy" trace file that has only the format type set.
811 *
812 * @param uri A valid (but fake) URI indicating the format of the dummy trace that is to be created.
813 * @return An opaque pointer to a (sparsely initialised) libtrace_t
814 *
815 * Only the format portion of the uri parameter matters - the 'file' being
816 * opened does not have to exist.
817 *
818 * @note IMPORTANT: Do not attempt to call trace_read_packet or other such
819 * functions with the dummy trace. Its intended purpose is to provide access
820 * to the format functions where the original trace may no longer exist or is
821 * not the correct format, e.g. reading ERF packets from an RT input.
822 */
823DLLEXPORT libtrace_t *trace_create_dead(const char *uri);
824
825/** Creates a trace output file from a URI.
826 *
827 * @param uri The uri string describing the output format and destination
828 * @return An opaque pointer to a libtrace_output_t
829 *
830 * Valid URIs include:
831 *  - erf:/path/to/erf/file
832 *  - pcap:/path/to/pcap/file
833 *
834 *  If an error occured when attempting to open the output trace, a trace is
835 *  still returned but trace_errno will be set. Use trace_is_err_out() and
836 *  trace_perror_output() to get more information.
837 */
838DLLEXPORT libtrace_out_t *trace_create_output(const char *uri);
839
840/** Start an input trace
841 * @param libtrace      The trace to start
842 * @return 0 on success, -1 on failure
843 *
844 * This does the actual work of starting the input trace and applying
845 * all the config options.  This may fail, returning -1. The libtrace error
846 * handling functions can be used to get more information about what
847 * specifically went wrong.
848 */
849DLLEXPORT int trace_start(libtrace_t *libtrace);
850
851/** Pauses an input trace
852 * @param libtrace      The trace to pause
853 * @return 0 on success, -1 on failure
854 *
855 * This stops an input trace that is in progress and returns you to the
856 * configuration state.  Any packets that arrive on a live capture after
857 * trace_pause() has been called will be discarded.  To resume the trace, call
858 * trace_start().
859 */
860DLLEXPORT int trace_pause(libtrace_t *libtrace);
861
862/** Start an output trace
863 * @param libtrace      The trace to start
864 * @return 0 on success, -1 on failure
865 *
866 * This does the actual work with starting a trace capable of writing packets. 
867 * This generally creates the output file.
868 */
869DLLEXPORT int trace_start_output(libtrace_out_t *libtrace);
870
871/** Valid configuration options for input traces */
872typedef enum {
873        /** Maximum number of bytes to be captured for any given packet */
874        TRACE_OPTION_SNAPLEN,   
875
876        /** If enabled, places a live capture interface into promiscuous mode */
877        TRACE_OPTION_PROMISC,   
878
879        /** Apply this filter to all packets read from this trace */
880        TRACE_OPTION_FILTER,   
881
882        /** Defines the frequency of meta-data reporting, e.g. DUCK packets */
883        TRACE_OPTION_META_FREQ,
884
885        /** If enabled, the libtrace event API will ignore time gaps between
886         * packets when reading from a trace file */
887        TRACE_OPTION_EVENT_REALTIME
888} trace_option_t;
889
890/** Sets an input config option
891 * @param libtrace      The trace object to apply the option to
892 * @param option        The option to set
893 * @param value         The value to set the option to
894 * @return -1 if option configuration failed, 0 otherwise
895 * This should be called after trace_create, and before trace_start
896 */
897DLLEXPORT int trace_config(libtrace_t *libtrace,
898                trace_option_t option,
899                void *value);
900
901/** Valid compression types
902 * Note, this must be kept in sync with WANDIO_COMPRESS_* numbers in wandio.h
903 */
904typedef enum {
905        TRACE_OPTION_COMPRESSTYPE_NONE = 0, /**< No compression */
906        TRACE_OPTION_COMPRESSTYPE_ZLIB = 1, /**< GZip Compression */
907        TRACE_OPTION_COMPRESSTYPE_BZ2  = 2, /**< BZip2 Compression */
908        TRACE_OPTION_COMPRESSTYPE_LZO  = 3  /**< LZO Compression */
909} trace_option_compresstype_t;
910
911/** Valid configuration options for output traces */
912typedef enum {
913        /** File flags to use when opening an output file, e.g. O_APPEND */
914        TRACE_OPTION_OUTPUT_FILEFLAGS,
915        /** Compression level: 0 = no compression, 1 = faster compression,
916         * 9 = better compression */
917        TRACE_OPTION_OUTPUT_COMPRESS,
918        /** Compression type, see trace_option_compresstype_t */
919        TRACE_OPTION_OUTPUT_COMPRESSTYPE
920} trace_option_output_t;
921
922/** Sets an output config option
923 *
924 * @param libtrace      The output trace object to apply the option to
925 * @param option        The option to set
926 * @param value         The value to set the option to
927 * @return -1 if option configuration failed, 0 otherwise
928 * This should be called after trace_create_output, and before
929 * trace_start_output
930 */
931DLLEXPORT int trace_config_output(libtrace_out_t *libtrace,
932                trace_option_output_t option,
933                void *value
934                );
935
936/** Close an input trace, freeing up any resources it may have been using
937 *
938 * @param trace         The input trace to be destroyed
939 *
940 */
941DLLEXPORT void trace_destroy(libtrace_t *trace);
942
943/** Close a dummy trace file, freeing up any resources it may have been using
944 * @param trace         The dummy trace to be destroyed
945 */
946DLLEXPORT void trace_destroy_dead(libtrace_t *trace);
947
948/** Close an output trace, freeing up any resources it may have been using
949 * @param trace         The output trace to be destroyed
950 */
951DLLEXPORT void trace_destroy_output(libtrace_out_t *trace);
952
953/** Check (and clear) the current error state of an input trace
954 * @param trace         The input trace to check the error state on
955 * @return The current error status and message
956 *
957 * This reads and returns the current error state and sets the current error
958 * to "no error".
959 */
960DLLEXPORT libtrace_err_t trace_get_err(libtrace_t *trace);
961
962/** Indicate if there has been an error on an input trace
963 * @param trace         The input trace to check the error state on
964 * @return true if an error has occurred, false otherwise
965 *
966 * @note This does not clear the error status, and only returns true or false.
967 */
968DLLEXPORT bool trace_is_err(libtrace_t *trace);
969
970/** Outputs the error message for an input trace to stderr and clear the error
971 * status.
972 * @param trace         The input trace with the error to output
973 * @param msg           The message to prepend to the error
974 *
975 * This function does clear the error status.
976 */
977DLLEXPORT void trace_perror(libtrace_t *trace, const char *msg,...) PRINTF(2,3);
978
979/** Checks (and clears) the current error state for an output trace
980 * @param trace         The output trace to check the error state on
981 * @return The current error status and message
982 *
983 * This reads and returns the current error state and sets the current error
984 * to "no error".
985 */
986DLLEXPORT libtrace_err_t trace_get_err_output(libtrace_out_t *trace);
987
988/** Indicates if there is an error on an output trace
989 * @param trace         The output trace to check the error state on
990 * @return true if an error has occurred, false otherwise.
991 *
992 * This does not clear the error status, and only returns true or false.
993 */
994DLLEXPORT bool trace_is_err_output(libtrace_out_t *trace);
995
996/** Outputs the error message for an output trace to stderr and clear the error
997 * status.
998 * @param trace         The output trace with the error to output
999 * @param msg           The message to prepend to the error
1000 * This function does clear the error status.
1001 */
1002DLLEXPORT void trace_perror_output(libtrace_out_t *trace, const char *msg,...)
1003        PRINTF(2,3);
1004
1005/** Returns the number of packets observed on an input trace.
1006 * Includes the number of packets counted as early as possible, before
1007 * filtering, and includes dropped packets.
1008 *
1009 * @param trace         The input trace to examine
1010 * @returns The number of packets seen at the capture point before filtering.
1011 *
1012 * If the number is not known, this function will return UINT64_MAX
1013 */
1014DLLEXPORT
1015uint64_t trace_get_received_packets(libtrace_t *trace);
1016
1017/** Returns the number of packets that were captured, but discarded for not
1018 * matching a provided filter.
1019 *
1020 * @param trace         The input trace to examine
1021 * @returns The number of packets that were successfully captured, but filtered
1022 *
1023 * If the number is not known, this function will return UINT64_MAX
1024 */
1025DLLEXPORT
1026uint64_t trace_get_filtered_packets(libtrace_t *trace);
1027
1028/** Returns the number of packets that have been dropped on an input trace due
1029 * to lack of buffer space on the capturing device.
1030 *
1031 * @param trace         The input trace to examine
1032 * @returns The number of packets captured, but dropped due to buffer overruns
1033 *
1034 * If the number is not known, this function will return UINT64_MAX
1035 */
1036DLLEXPORT
1037uint64_t trace_get_dropped_packets(libtrace_t *trace);
1038
1039/** Returns the number of packets that have been read from the input trace using
1040 * trace_read_packet().
1041 *
1042 * @param trace         The input trace to examine
1043 * @returns The number of packets that have been read by the libtrace user.
1044 *
1045 * If the number is not known, this function will return UINT64_MAX
1046 */
1047DLLEXPORT
1048uint64_t trace_get_accepted_packets(libtrace_t *trace);
1049
1050
1051/*@}*/
1052
1053/** @name Reading / Writing packets
1054 * These members deal with creating, reading and writing packets
1055 *
1056 * @{
1057 */
1058
1059/** Create a new packet object
1060 *
1061 * @return A pointer to an initialised libtrace_packet_t object
1062 */
1063DLLEXPORT libtrace_packet_t *trace_create_packet(void);
1064
1065/** Copy a packet object
1066 * @param packet        The source packet to copy
1067 * @return A new packet which has the same content as the source packet
1068 *
1069 * @note This always involves a copy, which can be slow.  Use of this
1070 * function should be avoided where possible.
1071 *
1072 * @par The reason you would want to use this function is that a zerocopied
1073 * packet from a device will be stored using memory owned by the device which
1074 * may be a limited resource. Copying the packet will ensure that the packet
1075 * is now stored in memory owned and managed by libtrace.
1076 */
1077DLLEXPORT libtrace_packet_t *trace_copy_packet(const libtrace_packet_t *packet);
1078
1079/** Destroy a packet object
1080 * @param packet        The packet to be destroyed
1081 *
1082 */
1083DLLEXPORT void trace_destroy_packet(libtrace_packet_t *packet);
1084
1085
1086/** Read the next packet from an input trace
1087 *
1088 * @param trace         The libtrace opaque pointer for the input trace
1089 * @param packet        The packet opaque pointer
1090 * @return 0 on EOF, negative value on error, number of bytes read when successful.
1091 *
1092 * @note The number of bytes read is usually (but not always) the same as
1093 * trace_get_framing_length()+trace_get_capture_length() depending on the
1094 * trace format.
1095 *
1096 * @note The trace must have been started with trace_start before calling
1097 * this function
1098 *
1099 * @note When reading from a live capture, this function will block until a
1100 * packet is observed on the capture interface. The libtrace event API
1101 * (e.g. trace_event()) should be used if non-blocking operation is required.
1102 */
1103DLLEXPORT int trace_read_packet(libtrace_t *trace, libtrace_packet_t *packet);
1104
1105/** Event types
1106 * see \ref libtrace_eventobj_t and \ref trace_event
1107 */
1108typedef enum {
1109        TRACE_EVENT_IOWAIT,     /**< Wait on the given file descriptor */
1110        TRACE_EVENT_SLEEP,      /**< Sleep for the given amount of time */
1111        TRACE_EVENT_PACKET,     /**< Packet has been read from input trace */
1112        TRACE_EVENT_TERMINATE   /**< End of input trace */
1113} libtrace_event_t;
1114
1115/** Structure returned by libtrace_event explaining what the current event is */
1116typedef struct libtrace_eventobj_t {
1117        libtrace_event_t type; /**< Event type (iowait,sleep,packet) */
1118       
1119        /** If the event is IOWAIT, the file descriptor to wait on */
1120        int fd;               
1121        /** If the event is SLEEP, the amount of time to sleep for in seconds */
1122        double seconds;       
1123        /** If the event is PACKET, the value returned by trace_read_packet() */
1124        int size;
1125} libtrace_eventobj_t;
1126
1127/** Processes the next libtrace event from an input trace.
1128 * @param trace The libtrace opaque pointer for the input trace
1129 * @param packet The libtrace_packet opaque pointer to use for reading packets
1130 * @return A libtrace_event struct containing the event type and details of the event.
1131 *
1132 * Type can be:
1133 *  TRACE_EVENT_IOWAIT  Waiting on I/O on a file descriptor
1134 *  TRACE_EVENT_SLEEP   Wait a specified amount of time for the next event
1135 *  TRACE_EVENT_PACKET  Packet was read from the trace
1136 *  TRACE_EVENT_TERMINATE Trace terminated (perhaps with an error condition)
1137 */
1138DLLEXPORT libtrace_eventobj_t trace_event(libtrace_t *trace,
1139                libtrace_packet_t *packet);
1140
1141
1142/** Write one packet out to the output trace
1143 *
1144 * @param trace         The libtrace_out opaque pointer for the output trace
1145 * @param packet        The packet opaque pointer of the packet to be written
1146 * @return The number of bytes written out, if zero or negative then an error has occured.
1147 */
1148DLLEXPORT int trace_write_packet(libtrace_out_t *trace, libtrace_packet_t *packet);
1149
1150/** Gets the capture format for a given packet.
1151 * @param packet        The packet to get the capture format for.
1152 * @return The capture format of the packet
1153 *
1154 * @note Due to ability to convert packets between formats relatively easily
1155 * in Libtrace, the format of the packet right now may not be the format that
1156 * the packet was originally captured with.
1157 */
1158DLLEXPORT
1159enum base_format_t trace_get_format(struct libtrace_packet_t *packet);
1160
1161/** Construct a libtrace packet from a buffer containing the packet payload.
1162 * @param[in,out] packet        Libtrace Packet object to update with the new
1163 *                              data.
1164 * @param linktype              The linktype of the packet data.
1165 * @param[in] data              The packet data (including linklayer).
1166 * @param len                   Length of packet data provided in the buffer.
1167 *
1168 * @note The constructed packet will be in the PCAP format.
1169 *
1170 * @note To be useful, the provided buffer must start with the layer 2 header
1171 * (or a metadata header, if desired).
1172 */
1173DLLEXPORT
1174void trace_construct_packet(libtrace_packet_t *packet,
1175                libtrace_linktype_t linktype, const void *data, uint16_t len);
1176
1177/*@}*/
1178
1179/** @name Protocol decodes
1180 * These functions locate and return a pointer to various headers inside a
1181 * packet
1182 *
1183 * A packet is divided up into several "layers.":
1184 *
1185 * @li Framing header -- This is the header provided by the capture format
1186 * itself rather than anything that was sent over the network. This provides
1187 * basic details about the packet record including capture lengths, wire
1188 * lengths, timestamps, direction information and any other metadata that is
1189 * part of the capture format. 
1190 *
1191 * @li Metadata header (optional) -- A header containing metadata about a
1192 * packet that was captured, but the metadata was not transmitted over the
1193 * wire.  Some examples include RadioTap and Linux_sll headers.  This can be
1194 * retrieved by trace_get_packet_meta(), or skipped using
1195 * trace_get_payload_from_meta(). There may be multiple "metadata" headers on
1196 * a packet.
1197 *
1198 * @li Layer 2/Link layer/Datalink header -- This can be retrieved by
1199 * trace_get_layer2(), or skipped using trace_get_payload_from_layer2().
1200 *
1201 * @li Layer 3/IP/IPv6 -- This can be retrieved by trace_get_layer3().  As a
1202 * convenience trace_get_ip()/trace_get_ip6() can be used to find an IPv4/IPv6
1203 * header.
1204 *
1205 * @li Layer 5/transport -- These are protocols carried in IPv4/IPv6 frames.
1206 * These can be retrieved using trace_get_transport().
1207 *
1208 * @{
1209 */
1210
1211
1212/** Gets a pointer to the first byte of the packet as it was captured and
1213 * returns its corresponding linktype and capture length.
1214 *
1215 * Use this function instead of the deprecated trace_get_link().
1216 *
1217 * @param packet The packet to get the buffer from
1218 * @param[out] linktype The linktype of the returned pointer
1219 * @param[out] remaining The capture length (the number of captured bytes from
1220 * the returned pointer)
1221 * @return A pointer to the first byte of the packet
1222 */
1223DLLEXPORT void *trace_get_packet_buffer(const libtrace_packet_t *packet,
1224                libtrace_linktype_t *linktype, uint32_t *remaining);
1225
1226/** Get a pointer to the link layer for a given packet
1227 * @param packet        The packet to get the link layer for
1228 *
1229 * @return A pointer to the link layer, or NULL if there is no link layer
1230 *
1231 * @deprecated This function is deprecated: Use trace_get_packet_buffer() or
1232 * one of the trace_get_layer*() functions instead.
1233 * @note You should call trace_get_link_type to find out what type of link
1234 * layer has been returned to you.
1235 */
1236DLLEXPORT SIMPLE_FUNCTION DEPRECATED
1237void *trace_get_link(const libtrace_packet_t *packet);
1238
1239/** Get a pointer to the IPv4 header (if any) for a given packet
1240 * @param packet        The packet to get the IPv4 header for
1241 *
1242 * @return A pointer to the IPv4 header, or NULL if there is no IPv4 header
1243 *
1244 * If a partial IP header is present, i.e. the packet has been truncated before
1245 * the end of the IP header, this function will return NULL.
1246 *
1247 * You should consider using \ref trace_get_layer3 instead of this function.
1248 */
1249DLLEXPORT SIMPLE_FUNCTION
1250libtrace_ip_t *trace_get_ip(libtrace_packet_t *packet);
1251
1252/** get a pointer to the IPv6 header (if any)
1253 * @param packet        The packet to get the IPv6 header for
1254 *
1255 * @return A pointer to the IPv6 header, or NULL if there is no IPv6 header
1256 *
1257 * If a partial IPv6 header is present, i.e. the packet has been truncated
1258 * before the end of the IP header, this function will return NULL.
1259 *
1260 * You should consider using \ref trace_get_layer3 instead of this function.
1261 */
1262DLLEXPORT SIMPLE_FUNCTION
1263libtrace_ip6_t *trace_get_ip6(libtrace_packet_t *packet);
1264
1265/** Return a pointer to the first metadata header in a packet, if present.
1266 *
1267 * This function takes a pointer to a libtrace packet and if any metadata
1268 * headers exist, returns a pointer to the first one, along with its
1269 * corresponding linktype.
1270 *
1271 * If no metadata headers exist in the packet, NULL is returned.
1272 *
1273 * A metadata header is a header that was prepended by the capturing device,
1274 * such as a Linux SLL header, or a Radiotap wireless monitoring header.
1275 * Subsequent metadata headers may be accessed with the
1276 * trace_get_payload_from_meta(...) function.
1277 *
1278 * @param packet The libtrace packet
1279 * @param[out] linktype The linktype of the returned metadata header
1280 * @param[out] remaining The number of bytes captured after the returned
1281 * pointer.
1282 * @return A pointer to the first metadata header, or NULL if there are no
1283 * metadata headers present.
1284 *
1285 * remaining may be NULL, however linktype must be provided.
1286 */
1287DLLEXPORT void *trace_get_packet_meta(const libtrace_packet_t *packet,
1288                libtrace_linktype_t *linktype,
1289                uint32_t *remaining);
1290
1291/** Returns the payload of a metadata header.
1292 *
1293 * This function takes a pointer to the start of a metadata header (either
1294 * obtained via trace_get_packet_meta(...) or by a previous call to
1295 * trace_get_payload_from_meta(...)) along with its corresponding linktype and
1296 * returns the payload, i.e. the next header. It will also update the linktype
1297 * parameter to indicate the type of payload.
1298 * 
1299 * If the linktype indicates that the header passed in is not a metadata
1300 * header, the function returns NULL to indicate this. The linktype remains
1301 * unchanged in this case.
1302 *
1303 * This function allows the user to iterate through metadata headers which are
1304 * sometimes present before the actual packet as it was received on the wire.
1305 * Examples of metadata headers include the Linux SLL header and the Radiotap
1306 * wireless monitoring header.
1307 *
1308 * If the metadata header passed into this function is truncated, this
1309 * function will return NULL, and remaining will be set to 0.
1310 *
1311 * If there are 0 bytes of payload following the provided metadata header, the
1312 * function will return a pointer to where the header would otherwise be and
1313 * remaining will be 0.
1314 *
1315 * Therefore, be sure to check the value of remaining after calling this
1316 * function!
1317 *
1318 * @param[in] meta A pointer to a metadata header
1319 * @param[in,out] linktype The linktype of meta (updated to indicate the
1320 * linktype of the returned header if applicable).
1321 * @param[in,out] remaining The number of bytes after the meta pointer.
1322 * @return A pointer to the payload of the metadata header. If meta is not a
1323 * pointer to a metadata header, NULL is returned and linktype remains
1324 * unchanged.
1325 *
1326 * All parameters are mandatory.
1327 */
1328DLLEXPORT void *trace_get_payload_from_meta(const void *meta,
1329                libtrace_linktype_t *linktype,
1330                uint32_t *remaining);
1331
1332
1333/** Get a pointer to the layer 2 header. Generally this is the first byte of the
1334 * packet as it was seen on the wire.
1335 *
1336 * This function takes a libtrace packet and skips over any metadata headers if
1337 * present (such as Linux SLL or Radiotap) and returns a pointer to the first
1338 * byte of the packet that was actually received by the network interface.
1339 *
1340 * @param packet The libtrace packet to find the layer 2 header for
1341 * @param[out] linktype The linktype of the returned layer 2 header
1342 * @param[out] remaining The number of bytes left in the packet after the
1343 * returned pointer.
1344 * @return A pointer to the first byte of the packet as it was seen on the
1345 * wire. If no layer 2 header is present, this function will return NULL.
1346 *
1347 * remaining may be NULL, otherwise it will be filled in by the function.
1348 */
1349DLLEXPORT void *trace_get_layer2(const libtrace_packet_t *packet,
1350                libtrace_linktype_t *linktype,
1351                uint32_t *remaining);
1352
1353/** Gets a pointer to the next header following a layer 2 header
1354 *
1355 * @param l2                    The pointer to the current layer 2 header
1356 * @param linktype              The type of the layer 2 header
1357 * @param[out] ethertype        An optional output variable of the ethernet type of the new header
1358 * @param[in,out] remaining     Updated with the number of captured bytes
1359                                remaining
1360 *
1361 * @return A pointer to the header following the provided layer 2 header, or
1362 * NULL if no subsequent header is present.
1363 *
1364 * Remaining must point to the number of bytes captured from the layer 2 header
1365 * and beyond.  It will be decremented by the number of bytes skipped to find
1366 * the payload.
1367 *
1368 * If the layer 2 header is complete but there are zero bytes of payload after
1369 * the end of the header, a pointer to where the payload would be is returned
1370 * and remaining will be set to 0.  If the layer 2 header is incomplete
1371 * (truncated), then NULL is returned and remaining will be set to 0.
1372 * Therefore, it is very important to check the value of remaining after
1373 * calling this function.
1374 *
1375 */
1376DLLEXPORT void *trace_get_payload_from_layer2(void *l2,
1377                libtrace_linktype_t linktype,
1378                uint16_t *ethertype,
1379                uint32_t *remaining);
1380
1381
1382/** Get a pointer to the layer 3 (e.g. IP) header.
1383 * @param packet  The libtrace packet to find the layer 3 header for
1384 * @param[out] ethertype The ethertype of the layer 3 header
1385 * @param[out] remaining The amount of captured data remaining in the packet starting from the returned pointer, i.e. including the layer 3 header.
1386 *
1387 * @return A pointer to the layer 3 header. If no layer 3 header is present in
1388 * the packet, NULL is returned. If the layer 3 header is truncated, a valid
1389 * pointer will still be returned so be sure to check the value of remaining
1390 * before attempting to process the returned header.
1391 *
1392 * remaining may be NULL, otherwise it will be set to the number of captured
1393 * bytes after the pointer returned.
1394 */
1395DLLEXPORT
1396void *trace_get_layer3(const libtrace_packet_t *packet,
1397                uint16_t *ethertype, uint32_t *remaining);
1398
1399/** Gets a pointer to the transport layer header (if any)
1400 * @param packet   The libtrace packet to find the transport header for
1401 * @param[out] proto    The protocol present at the transport layer.
1402 * @param[out] remaining The amount of captured data remaining in the packet
1403 * starting from the returned pointer, i.e. including the transport header.
1404 *
1405 * @return A pointer to the transport layer header. If no transport header is
1406 * present in the packet, NULL is returned. If the transport header is
1407 * truncated, a valid pointer will still be returned so be sure to check the
1408 * value of remaining before attempting to process the returned header.
1409 *
1410 * remaining may be NULL, otherwise it will be set to the number of captured
1411 * bytes after the returned pointer.
1412 *
1413 * @note proto may be NULL if proto is unneeded.
1414 */
1415DLLEXPORT void *trace_get_transport(const libtrace_packet_t *packet,
1416                uint8_t *proto, uint32_t *remaining);
1417
1418/** Gets a pointer to the payload following an IPv4 header
1419 * @param ip            The IPv4 Header
1420 * @param[out] proto    The protocol of the header following the IPv4 header
1421 * @param[in,out] remaining Updated with the number of captured bytes remaining
1422 *
1423 * @return A pointer to the transport layer header, or NULL if no subsequent
1424 * header is present.
1425 *
1426 * When calling this function, remaining must contain the number of captured
1427 * bytes remaining in the packet starting from the IPv4 header (including the
1428 * IPv4 header itself).
1429 *
1430 * remaining will be decremented by the size of the IPv4 header (including any
1431 * options). If the IPv4 header is complete but there are zero bytes of payload
1432 * after the IPv4 header, a pointer to where the payload would be is returned
1433 * and remaining will be set to 0.  If the IPv4 header is incomplete, NULL will
1434 * be returned and remaining will be set to 0. Therefore, it is very important
1435 * to check the value of remaining after calling this function.
1436 *
1437 * proto may be NULL, in which case it won't be updated.
1438 *
1439 * @note This is similar to trace_get_transport_from_ip in libtrace2
1440 */
1441DLLEXPORT void *trace_get_payload_from_ip(libtrace_ip_t *ip, uint8_t *proto,
1442                uint32_t *remaining);
1443
1444/** Gets a pointer to the payload following an IPv6 header
1445 * @param ipptr         The IPv6 Header
1446 * @param[out] proto    The protocol of the header following the IPv6 header
1447 * @param[in,out] remaining Updated with the number of captured bytes remaining
1448 *
1449 * @return A pointer to the transport layer header, or NULL if no subsequent
1450 * header is present.
1451 *
1452 * When calling this function, remaining must contain the number of captured
1453 * bytes remaining in the packet starting from the IPv6 header (including the
1454 * IPv6 header itself).
1455 *
1456 * remaining will be decremented by the size of the IPv6 header (including any
1457 * options). If the IPv6 header is complete but there are zero bytes of payload
1458 * after the IPv6 header, a pointer to where the payload would be is returned
1459 * and remaining will be set to 0.  If the IPv6 header is incomplete, NULL will
1460 * be returned and remaining will be set to 0. Therefore, it is very important
1461 * to check the value of remaining after calling this function.
1462 *
1463 * proto may be NULL, in which case it won't be updated.
1464 *
1465 */
1466DLLEXPORT void *trace_get_payload_from_ip6(libtrace_ip6_t *ipptr,
1467                uint8_t *proto, uint32_t *remaining);
1468
1469/** Gets a pointer to the payload following a link header
1470 * @param linkptr       A pointer to the link layer header
1471 * @param linktype      The linktype of the link header being examined
1472 * @param[out] type     An output variable for the ethernet type
1473 * @param[in,out] remaining Updated with the number of captured bytes remaining
1474 *
1475 * @return A pointer to the header following the link header, or NULL if no
1476 * subsequent header is present.
1477 *
1478 * When calling this function, remaining must contain the number of captured
1479 * bytes remaining in the packet starting from the link header (including the
1480 * link header itself). remaining will be updated to contain the number of
1481 * bytes remaining after the link header has been skipped.
1482 *
1483 * @deprecated This function is deprecated: you should be using
1484 * trace_get_payload_from_layer2() or trace_get_payload_from_meta() instead.
1485 *
1486 */
1487DLLEXPORT void *trace_get_payload_from_link(void *linkptr,
1488                libtrace_linktype_t linktype,
1489                uint16_t *type, uint32_t *remaining);
1490
1491/** Gets a pointer to the payload following an 802.1q (VLAN) header.
1492 * @param vlan      A pointer to the VLAN header
1493 * @param[out] type  The ethernet type, replaced with the VLAN ether type
1494 * @param[in,out] remaining Updated with the number of captured bytes remaining
1495 *
1496 * @return A pointer to the header beyond the VLAN header, if one is present.
1497 * Otherwise, returns NULL. 
1498 *
1499 * When calling this function, remaining must contain the number of captured
1500 * bytes remaining in the packet starting from the VLAN header (including the
1501 * VLAN header itself). remaining will be updated to contain the number of
1502 * bytes remaining after the VLAN header has been skipped.
1503 *
1504 * If the VLAN header is complete but there are zero bytes of payload after
1505 * the VLAN header, a pointer to where the payload would be is returned and
1506 * remaining will be set to 0.  If the VLAN header is incomplete, NULL will be
1507 * returned and remaining will be set to 0. Therefore, it is important to check
1508 * the value of remaining after calling this function.
1509 *
1510 * type will be set to the ethertype of the VLAN payload. This parameter is not
1511 * mandatory, but is highly recommended.
1512 *
1513 */
1514DLLEXPORT void *trace_get_payload_from_vlan(
1515                void *vlan, uint16_t *type, uint32_t *remaining);
1516
1517/** Gets a pointer to the payload following an MPLS header.
1518 * @param mpls      A pointer to the MPLS header
1519 * @param[out] type  The ethernet type, replaced by the ether type of the
1520 * returned header - 0x0000 if an Ethernet header is returned
1521 * @param[in,out] remaining Updated with the number of captured bytes remaining
1522 *
1523 * @return A pointer to the header beyond the MPLS label, if one is present.
1524 * Will return NULL if there is not enough bytes remaining to skip past the
1525 * MPLS label.
1526 *
1527 * When calling this function, remaining must contain the number of captured
1528 * bytes remaining in the packet starting from the MPLS header (including the
1529 * MPLS header itself). remaining will be updated to contain the number of
1530 * bytes remaining after the MPLS header has been skipped.
1531 *
1532 * If the MPLS header is complete but there are zero bytes of payload after
1533 * the MPLS header, a pointer to where the payload would be is returned and
1534 * remaining will be set to 0.  If the MPLS header is incomplete, NULL will be
1535 * returned and remaining will be set to 0. Therefore, it is important to check
1536 * the value of remaining after calling this function.
1537 *
1538 * type will be set to the ethertype of the MPLS payload. This parameter is
1539 * mandatory - it may not be NULL.
1540 *
1541 * @note This function will only remove one MPLS label at a time - the type
1542 * will be set to 0x8847 if there is another MPLS label following the one
1543 * skipped by this function.
1544 *
1545 */
1546DLLEXPORT void *trace_get_payload_from_mpls(
1547                void *mpls, uint16_t *type, uint32_t *remaining);
1548
1549/** Gets a pointer to the payload following a PPPoE header
1550 * @param pppoe      A pointer to the PPPoE header
1551 * @param[out] type  The ethernet type, replaced by the ether type of the
1552 * returned header - 0x0000 if an Ethernet header is returned
1553 * @param[in,out] remaining  Updated with the number of captured bytes remaining
1554 *
1555 * @return A pointer to the header beyond the PPPoE header. NOTE that this
1556 * function will also skip over the PPP header that will immediately follow
1557 * the PPPoE header. This function will return NULL if there are not enough
1558 * bytes remaining to skip past both the PPPoE and PPP headers.
1559 *
1560 * When calling this function, remaining must contain the number of captured
1561 * bytes remaining in the packet starting from the PPPoE header (including the
1562 * PPPoE header itself). remaining will be updated to contain the number of
1563 * bytes remaining after the PPPoE and PPP headers have been removed.
1564 *
1565 * If the PPPoE and PPP headers are complete but there are zero bytes of
1566 * payload after the PPP header, a pointer to where the payload would be is
1567 * returned and remaining will be set to 0.  If the PPPoE or PPP header is
1568 * incomplete, NULL will be returned and remaining will be set to 0. Therefore,
1569 * it is important to check the value of remaining after calling this function.
1570 *
1571 * type will be set to the ether type of the PPP payload. This parameter is
1572 * mandatory - it may not be NULL.
1573 *
1574 */
1575DLLEXPORT void *trace_get_payload_from_pppoe(
1576                void *pppoe, uint16_t *type, uint32_t *remaining);
1577
1578/** Gets a pointer to the payload following a TCP header
1579 * @param tcp           A pointer to the TCP header
1580 * @param[in,out] remaining Updated with the number of captured bytes remaining
1581 *
1582 * @return A pointer to the TCP payload, or NULL if the TCP header is truncated.
1583 *
1584 * When calling this function, remaining must contain the number of captured
1585 * bytes remaining in the packet starting from the TCP header (including the
1586 * TCP header itself). remaining will be updated to contain the number of
1587 * bytes remaining after the TCP header has been skipped.
1588 *
1589 * If the TCP header is complete but there are zero bytes of payload after
1590 * the TCP header, a pointer to where the payload would be is returned and
1591 * remaining will be set to 0.  If the TCP header is incomplete, NULL will be
1592 * returned and remaining will be set to 0. Therefore, it is important to check
1593 * the value of remaining after calling this function.
1594 *
1595 */
1596DLLEXPORT void *trace_get_payload_from_tcp(libtrace_tcp_t *tcp,
1597                uint32_t *remaining);
1598
1599/** Gets a pointer to the payload following a UDP header
1600 * @param udp           A pointer to the UDP header
1601 * @param[in,out] remaining Updated with the number of captured bytes remaining
1602 *
1603 * @return A pointer to the UDP payload, or NULL if the UDP header is truncated.
1604 *
1605 * When calling this function, remaining must contain the number of captured
1606 * bytes remaining in the packet starting from the UDP header (including the
1607 * UDP header itself). remaining will be updated to contain the number of
1608 * bytes remaining after the UDP header has been skipped.
1609 *
1610 * If the UDP header is complete but there are zero bytes of payload after
1611 * the UDP header, a pointer to where the payload would be is returned and
1612 * remaining will be set to 0.  If the UDP header is incomplete, NULL will be
1613 * returned and remaining will be set to 0. Therefore, it is important to check
1614 * the value of remaining after calling this function.
1615 *
1616 */
1617DLLEXPORT void *trace_get_payload_from_udp(libtrace_udp_t *udp, uint32_t *remaining);
1618
1619/** Gets a pointer to the payload following a ICMP header
1620 * @param icmp           A pointer to the ICMP header
1621 * @param[in,out] remaining Updated with the number of captured bytes remaining
1622 *
1623 * @return A pointer to the ICMP payload, or NULL if the ICMP header is
1624 * truncated.
1625 *
1626 * When calling this function, remaining must contain the number of captured
1627 * bytes remaining in the packet starting from the ICMP header (including the
1628 * ICMP header itself). remaining will be updated to contain the number of
1629 * bytes remaining after the ICMP header has been skipped.
1630 *
1631 * If the ICMP header is complete but there are zero bytes of payload after
1632 * the ICMP header, a pointer to where the payload would be is returned and
1633 * remaining will be set to 0.  If the ICMP header is incomplete, NULL will be
1634 * returned and remaining will be set to 0. Therefore, it is important to check
1635 * the value of remaining after calling this function.
1636 *
1637 * @note In the case of some ICMP messages, the payload may be the IP header
1638 * from the packet that triggered the ICMP message.
1639 *
1640 */
1641DLLEXPORT void *trace_get_payload_from_icmp(libtrace_icmp_t *icmp,
1642                uint32_t *remaining);
1643
1644/** Get a pointer to the TCP header (if present)
1645 * @param packet        The packet to get the TCP header from
1646 *
1647 * @return A pointer to the TCP header, or NULL if there is not a complete TCP
1648 * header present in the packet.
1649 *
1650 * This is a short-cut function enabling quick and easy access to the TCP
1651 * header if that is all you care about. However, we recommend the use of the
1652 * more generic trace_get_transport() function instead.
1653 *
1654 * @note Unlike trace_get_transport(), this function will return NULL if the
1655 * TCP header is incomplete or truncated.
1656 */
1657DLLEXPORT SIMPLE_FUNCTION
1658libtrace_tcp_t *trace_get_tcp(libtrace_packet_t *packet);
1659
1660/** Get a pointer to the TCP header following an IPv4 header (if present)
1661 * @param ip            The IP header to find the subsequent TCP header for
1662 * @param[in,out] remaining Updated with the number of captured bytes remaining
1663 *
1664 * @return A pointer to the TCP header, or NULL if no TCP header is present in
1665 * the packet.
1666 *
1667 * When calling this function, remaining must contain the number of captured
1668 * bytes remaining in the packet starting from the IP header (including the
1669 * IP header itself). remaining will be updated to contain the number of
1670 * bytes remaining after the IP header has been skipped.
1671 *
1672 * If the IP header is complete but there are zero bytes of payload after
1673 * the IP header, a pointer to where the payload would be is returned and
1674 * remaining will be set to 0.  If the IP header is incomplete, NULL will be
1675 * returned and remaining will be set to 0. Therefore, it is important to check
1676 * the value of remaining after calling this function.
1677 *
1678 * @note This function is rather redundant now that the layer 3 header is
1679 * cached. There should be no performance advantage for the user to call this
1680 * function over just calling trace_get_transport().
1681 *
1682 * @note The last parameter has changed from libtrace2
1683 */
1684DLLEXPORT SIMPLE_FUNCTION
1685libtrace_tcp_t *trace_get_tcp_from_ip(libtrace_ip_t *ip, uint32_t *remaining);
1686
1687/** Get a pointer to the UDP header (if present)
1688 * @param packet        The packet to get the UDP header from
1689 *
1690 * @return A pointer to the UDP header, or NULL if there is not a complete UDP
1691 * header present in the packet.
1692 *
1693 * This is a short-cut function enabling quick and easy access to the UDP
1694 * header if that is all you care about. However, we recommend the use of the
1695 * more generic trace_get_transport() function instead.
1696 *
1697 * @note Unlike trace_get_transport(), this function will return NULL if the
1698 * UDP header is incomplete or truncated.
1699 */
1700DLLEXPORT SIMPLE_FUNCTION
1701libtrace_udp_t *trace_get_udp(libtrace_packet_t *packet);
1702
1703/** Get a pointer to the UDP header following an IPv4 header (if present)
1704 * @param ip            The IP header to find the subsequent UDP header for
1705 * @param[in,out] remaining Updated with the number of captured bytes remaining
1706 *
1707 * @return A pointer to the UDP header, or NULL if no UDP header is present in
1708 * the packet.
1709 *
1710 * When calling this function, remaining must contain the number of captured
1711 * bytes remaining in the packet starting from the IP header (including the
1712 * IP header itself). remaining will be updated to contain the number of
1713 * bytes remaining after the IP header has been skipped.
1714 *
1715 * If the IP header is complete but there are zero bytes of payload after
1716 * the IP header, a pointer to where the payload would be is returned and
1717 * remaining will be set to 0.  If the IP header is incomplete, NULL will be
1718 * returned and remaining will be set to 0. Therefore, it is important to check
1719 * the value of remaining after calling this function.
1720 *
1721 * @note This function is rather redundant now that the layer 3 header is
1722 * cached. There should be no performance advantage for the user to call this
1723 * function over just calling trace_get_transport().
1724 *
1725 * @note The last parameter has changed from libtrace2
1726 */
1727DLLEXPORT SIMPLE_FUNCTION
1728libtrace_udp_t *trace_get_udp_from_ip(libtrace_ip_t *ip,uint32_t *remaining);
1729
1730/** Get a pointer to the ICMP header (if present)
1731 * @param packet        The packet to get the ICMP header from
1732 *
1733 * @return A pointer to the ICMP header, or NULL if there is not a complete
1734 * ICMP header present in the packet.
1735 *
1736 * This is a short-cut function enabling quick and easy access to the ICMP
1737 * header if that is all you care about. However, we recommend the use of the
1738 * more generic trace_get_transport() function instead.
1739 *
1740 * @note Unlike trace_get_transport(), this function will return NULL if the
1741 * ICMP header is incomplete or truncated.
1742 */
1743DLLEXPORT SIMPLE_FUNCTION
1744libtrace_icmp_t *trace_get_icmp(libtrace_packet_t *packet);
1745
1746/** Get a pointer to the ICMP header following an IPv4 header (if present)
1747 * @param ip            The IP header to find the subsequent ICMP header for
1748 * @param[in,out] remaining Updated with the number of captured bytes remaining
1749 *
1750 * @return A pointer to the ICMP header, or NULL if no UDP header is present in
1751 * the packet.
1752 *
1753 * When calling this function, remaining must contain the number of captured
1754 * bytes remaining in the packet starting from the IP header (including the
1755 * IP header itself). remaining will be updated to contain the number of
1756 * bytes remaining after the IP header has been skipped.
1757 *
1758 * If the IP header is complete but there are zero bytes of payload after
1759 * the IP header, a pointer to where the payload would be is returned and
1760 * remaining will be set to 0.  If the IP header is incomplete, NULL will be
1761 * returned and remaining will be set to 0. Therefore, it is important to check
1762 * the value of remaining after calling this function.
1763 *
1764 * @note This function is rather redundant now that the layer 3 header is
1765 * cached. There should be no performance advantage for the user to call this
1766 * function over just calling trace_get_transport().
1767 *
1768 * @note The last parameter has changed from libtrace2
1769 */
1770DLLEXPORT SIMPLE_FUNCTION
1771libtrace_icmp_t *trace_get_icmp_from_ip(libtrace_ip_t *ip,uint32_t *remaining);
1772
1773/** Gets the destination MAC address for a given packet
1774 * @param packet        The packet to extract the destination MAC address from
1775 *
1776 * @return A pointer to the destination MAC address field in the layer 2
1777 * header, (or NULL if there is no destination MAC address or layer 2 header
1778 * available)
1779 *
1780 * @note This is a zero-copy function, so the memory that the returned pointer
1781 * points to is part of the packet itself.
1782 */
1783DLLEXPORT SIMPLE_FUNCTION
1784uint8_t *trace_get_destination_mac(libtrace_packet_t *packet);
1785
1786/** Gets the source MAC address for a given packet
1787 * @param packet        The packet to extract the source MAC address from
1788 *
1789 * @return A pointer to the source MAC address field in the layer 2
1790 * header, (or NULL if there is no source MAC address or layer 2 header
1791 * available)
1792 *
1793 * @note This is a zero-copy function, so the memory that the returned pointer
1794 * points to is part of the packet itself.
1795 */
1796DLLEXPORT SIMPLE_FUNCTION
1797uint8_t *trace_get_source_mac(libtrace_packet_t *packet);
1798
1799/** Get the source IP address for a given packet
1800 * @param packet        The packet to extract the source IP address from
1801 * @param addr          A pointer to a sockaddr structure to store the address
1802 *                      in. If NULL, static storage is used instead.
1803 * @return A pointer to a sockaddr holding a v4 or v6 IP address or on some
1804 * platforms a sockaddr holding a MAC address. Returns NULL if no source IP
1805 * address was available.
1806 *
1807 * @note The best way to use this function is to pass in a pointer to the
1808 * struct sockaddr_storage for the addr parameter. This will avoid problems
1809 * with trying to shoe-horn an IPv6 address into a sockaddr that only supports
1810 * IPv4.
1811 */
1812DLLEXPORT SIMPLE_FUNCTION
1813struct sockaddr *trace_get_source_address(const libtrace_packet_t *packet,
1814                struct sockaddr *addr);
1815
1816/** Get the destination IP address for a given packet
1817 * @param packet        The packet to extract the destination IP address from
1818 * @param addr          A pointer to a sockaddr structure to store the address
1819 *                      in. If NULL, static storage is used instead.
1820 * @return A pointer to a sockaddr holding a v4 or v6 IP address or on some
1821 * platforms a sockaddr holding a MAC address. Returns NULL if no destination
1822 * IP address was available.
1823 *
1824 * @note The best way to use this function is to pass in a pointer to the
1825 * struct sockaddr_storage for the addr parameter. This will avoid problems
1826 * with trying to shoe-horn an IPv6 address into a sockaddr that only supports
1827 * IPv4.
1828 */
1829DLLEXPORT SIMPLE_FUNCTION
1830struct sockaddr *trace_get_destination_address(const libtrace_packet_t *packet,
1831                struct sockaddr *addr);
1832
1833
1834/** Parses an IP or TCP option
1835 * @param[in,out] ptr   The pointer to the current option
1836 * @param[in,out] len   The total length of all the remaining options
1837 * @param[out] type     The type of the option
1838 * @param[out] optlen   The length of the option
1839 * @param[out] data     The data of the option
1840 *
1841 * @return bool true if there is another option (and the fields are filled in)
1842 *               or false if this was the last option.
1843 *
1844 * This updates ptr to point to the next option after this one, and updates
1845 * len to be the number of bytes remaining in the options area.  Type is updated
1846 * to be the code of this option, and data points to the data of this option,
1847 * with optlen saying how many bytes there are.
1848 *
1849 * @note Beware of fragmented packets.
1850 */
1851DLLEXPORT int trace_get_next_option(unsigned char **ptr,int *len,
1852                        unsigned char *type,
1853                        unsigned char *optlen,
1854                        unsigned char **data);
1855
1856/*@}*/
1857
1858/** @name Time
1859 * These functions deal with the timestamp describing when a packet was
1860 * captured and can convert it into various formats
1861 * @{
1862 */
1863
1864/** Get the packet timestamp in the DAG time format
1865 * @param packet        The packet to extract the timestamp from
1866 *
1867 * @return a 64 bit timestamp in DAG ERF format (upper 32 bits are the seconds
1868 * past 1970-01-01, the lower 32bits are partial seconds)
1869 */
1870DLLEXPORT SIMPLE_FUNCTION
1871uint64_t trace_get_erf_timestamp(const libtrace_packet_t *packet);
1872
1873/** Get the packet timestamp as a struct timeval
1874 * @param packet        The packet to extract the timestamp from
1875 *
1876 * @return The time that this packet was captured in a struct timeval
1877 */
1878DLLEXPORT SIMPLE_FUNCTION
1879struct timeval trace_get_timeval(const libtrace_packet_t *packet);
1880
1881/** Get the packet timestamp as a struct timespec
1882 * @param packet        The packet to extract the timestamp from
1883 *
1884 * @return The time that this packet was captured in a struct timespec
1885 */
1886DLLEXPORT SIMPLE_FUNCTION
1887struct timespec trace_get_timespec(const libtrace_packet_t *packet);
1888
1889/** Get the packet timestamp in floating point seconds
1890 * @param packet        The packet to extract the timestamp from
1891 *
1892 * @return time that this packet was seen in 64-bit floating point seconds from
1893 * the UNIX epoch (1970-01-01 00:00:00 UTC).
1894 */
1895DLLEXPORT SIMPLE_FUNCTION
1896double trace_get_seconds(const libtrace_packet_t *packet);
1897
1898/** Seek within an input trace to a time specified in floating point seconds
1899 * @param trace         The input trace to seek within
1900 * @param seconds       The time to seek to, in floating point seconds
1901 * @return 0 on success, -1 if the seek fails. Use trace_perror() to determine
1902 * the error that occurred.
1903 *
1904 * This will make the next packet read to be the first packet to occur at or
1905 * after the specified time.  This must be called in the configuration state
1906 * (i.e. before trace_start() or after trace_pause()).
1907 *
1908 * The time format accepted by this function is 64-bit floating point seconds
1909 * since the UNIX epoch (1970-01-01 00:00:00 UTC), i.e. the same format as
1910 * trace_get_seconds().
1911 *
1912 * @note This function may be extremely slow.
1913 */
1914DLLEXPORT int trace_seek_seconds(libtrace_t *trace, double seconds);
1915
1916/** Seek within an input trace to a time specified as a timeval
1917 * @param trace         The input trace to seek within
1918 * @param tv            The time to seek to, as a timeval
1919 *
1920 * @return 0 on success, -1 if the seek fails. Use trace_perror() to determine
1921 * the error that occurred.
1922 *
1923 * This will make the next packet read to be the first packet to occur at or
1924 * after the specified time.  This must be called in the configuration state
1925 * (i.e. before trace_start() or after trace_pause()).
1926 *
1927 * @note This function may be extremely slow.
1928 */
1929DLLEXPORT int trace_seek_timeval(libtrace_t *trace, struct timeval tv);
1930
1931/** Seek within an input trace to a time specified as an ERF timestamp
1932 * @param trace         The input trace to seek within
1933 * @param ts            The time to seek to, as an ERF timestamp
1934 *
1935 * @return 0 on success, -1 if the seek fails. Use trace_perror() to determine
1936 * the error that occurred.
1937 *
1938 * This will make the next packet read to be the first packet to occur at or
1939 * after the specified time.  This must be called in the configuration state
1940 * (i.e. before trace_start() or after trace_pause()).
1941 *
1942 * The time format accepted by this function is the ERF timestamp, which is a
1943 * 64-bit value where the upper 32 bits are seconds since the UNIX epoch and
1944 * the lower 32 bits are partial seconds.
1945 *
1946 * @note This function may be extremely slow.
1947 */
1948DLLEXPORT int trace_seek_erf_timestamp(libtrace_t *trace, uint64_t ts);
1949
1950/*@}*/
1951
1952/** @name Sizes
1953 * This section deals with finding or setting the various different lengths
1954 * that a packet can have, e.g. capture lengths, wire lengths, etc.
1955 * @{
1956 */
1957/** Get the current size of the packet (in bytes), taking into account any
1958 * truncation or snapping that may have previously been performed.
1959 *
1960 * @param packet        The packet to determine the capture length for
1961 * @return The size of the packet read from the input trace, i.e. what is
1962 * actually available to libtrace at the moment.
1963 *
1964 * @note Most traces are header captures, so this value may not be the same
1965 * as the size of the packet when it was captured. Use trace_get_wire_length()
1966 * to get the original size of the packet.
1967 
1968 * @note This can (and often is) different for different packets in a trace!
1969 
1970 * @note This is sometimes called the "snaplen".
1971 *
1972 * @note The return size refers to the network-level payload of the packet and
1973 * does not include any capture framing headers. For example, an Ethernet
1974 * packet with an empty TCP packet will return sizeof(ethernet_header) +
1975 * sizeof(ip_header) + sizeof(tcp_header), but not the capture format
1976 * (pcap/erf/etc) header.
1977 */
1978DLLEXPORT SIMPLE_FUNCTION
1979size_t trace_get_capture_length(const libtrace_packet_t *packet);
1980
1981/** Get the size of the packet as it was originally seen on the wire (in bytes).
1982 * @param packet        The packet to determine the wire length for
1983 * @return The size of the packet as it was on the wire.
1984 *
1985 * @note This value may not be the same as the capture length, due to
1986 * truncation.
1987 *
1988 * @note trace_get_wire_length \em includes  the Frame Check Sequence. This is
1989 * different behaviour compared to most PCAP-based tools.
1990 *
1991 * @note The return size refers to the network-level payload of the packet and
1992 * does not include any capture framing headers. For example, an Ethernet
1993 * packet with an empty TCP packet will return sizeof(ethernet_header) +
1994 * sizeof(ip_header) + sizeof(tcp_header), but not the capture format
1995 * (pcap/erf/etc) header.
1996 */
1997DLLEXPORT SIMPLE_FUNCTION
1998size_t trace_get_wire_length(const libtrace_packet_t *packet);
1999
2000/** Get the length of the capture framing headers (in bytes).
2001 * @param packet        The packet to determine the framing length for
2002 * @return The size of the capture format header encapsulating the packet.
2003 *
2004 * @note This length corresponds to the difference between the amount of
2005 * memory required to store a captured packet and the capture length reported
2006 * by trace_capture_length()
2007 */
2008DLLEXPORT SIMPLE_FUNCTION
2009size_t trace_get_framing_length(const libtrace_packet_t *packet);
2010
2011/** Get the length of the original payload content of the packet (in bytes).
2012 * @param packet        The packet to determine the payload length for
2013 * @return The size of the packet payload (without headers). Returns 0 if
2014 * unable to calculate payload length correctly.
2015 *
2016 * This function reports the amount of data that followed the transport header
2017 * when the packet was originally captured, i.e. prior to any snapping. Best
2018 * described as the wire length minus the packet headers.
2019 *
2020 * Currently only supports some protocols and will return 0 if an unsupported
2021 * protocol header is encountered, or if one of the headers is truncated.
2022 *
2023 * @note Supports IPv4, IPv6, TCP, UDP and ICMP.
2024 */
2025DLLEXPORT SIMPLE_FUNCTION
2026size_t trace_get_payload_length(const libtrace_packet_t *packet);
2027
2028/** Truncate ("snap") the packet to the suggested length
2029 * @param packet        The packet to truncate
2030 * @param size          The new length of the packet (in bytes)
2031 *
2032 * @return The new capture length of the packet or the original capture
2033 * length of the packet if unchanged.
2034 *
2035 * This function will modify the capture length of the given packet. The wire
2036 * length will not be changed, so you can always determine what the original
2037 * packet size was, prior to the truncation.
2038 *
2039 * @note You can only use this function to decrease the capture length. Any
2040 * attempt to increase capture length will have no effect.
2041 */
2042DLLEXPORT size_t trace_set_capture_length(libtrace_packet_t *packet, size_t size);
2043
2044/*@}*/
2045
2046
2047/** Gets the link layer type for a packet
2048 * @param packet        The packet to extract the link layer type for
2049 * @return A libtrace_linktype_t describing the link layer protocol being used
2050 * by this packet.
2051 */
2052DLLEXPORT SIMPLE_FUNCTION
2053libtrace_linktype_t trace_get_link_type(const libtrace_packet_t *packet);
2054
2055/** Set the direction flag for a packet, if the capture format supports
2056 * direction tagging.
2057 *
2058 * @param packet        The packet to set the direction for
2059 * @param direction     The new direction
2060 * @returns -1 on error, or the direction that was set.
2061 *
2062 * @note Few capture formats actually support direction tagging. Most notably,
2063 * we cannot set the direction on PCAP packets.
2064 */
2065DLLEXPORT libtrace_direction_t trace_set_direction(libtrace_packet_t *packet, libtrace_direction_t direction);
2066
2067/** Get the direction flag for a packet, if it has one.
2068 * @param packet  The packet to get the direction for
2069 *
2070 * @return A value representing the direction flag, or -1 if this is not
2071 * supported by the capture format.
2072 *
2073 * The direction is defined as 0 for packets originating locally (ie, outbound)
2074 * and 1 for packets originating remotely (ie, inbound). Other values are
2075 * possible, which might be overloaded to mean special things for certain
2076 * traces, e.g. in the Waikato traces, 2 is used to represent an "Unknown"
2077 * direction.
2078 *
2079 * For DAG/ERF traces, the direction is extracted from the "Interface" bits in
2080 * the ERF header, which can range from 0 - 3.
2081 */
2082DLLEXPORT SIMPLE_FUNCTION
2083libtrace_direction_t trace_get_direction(const libtrace_packet_t *packet);
2084
2085/** @name BPF
2086 * This section deals with using Berkley Packet Filters to filter input traces
2087 * @{
2088 */
2089/** Creates a BPF filter
2090 * @param filterstring The filter string describing the BPF filter to create
2091 * @return An opaque pointer to a libtrace_filter_t object
2092 *
2093 * @note The filter is not actually compiled at this point, so no correctness
2094 * tests are performed here. trace_create_filter() will always return ok, but
2095 * if the filter is poorly constructed an error will be generated when the
2096 * filter is actually used.
2097 */
2098DLLEXPORT SIMPLE_FUNCTION
2099libtrace_filter_t *trace_create_filter(const char *filterstring);
2100
2101/** Create a BPF filter based on pre-compiled byte-code.
2102 * @param bf_insns      A pointer to the start of the byte-code
2103 * @param bf_len        The number of BPF instructions 
2104 * @return              An opaque pointer to a libtrace_filter_t object
2105 * @note                The supplied byte-code is not checked for correctness.
2106 *                      Instead, incorrect byte-code will generate an error
2107 *                      once the filter is actually used.
2108 * @author              Scott Raynel
2109 */
2110DLLEXPORT libtrace_filter_t *
2111trace_create_filter_from_bytecode(void *bf_insns, unsigned int bf_len);
2112
2113/** Apply a BPF filter to a packet
2114 * @param filter        The filter to be applied       
2115 * @param packet        The packet to be matched against the filter
2116 * @return >0 if the filter matches, 0 if it doesn't, -1 on error.
2117 *
2118 * @note Due to the way BPF filters are built, the filter is not actually
2119 * compiled until the first time trace_create_filter is called. If your filter
2120 * is incorrect, it will generate an error message and assert, exiting the
2121 * program. This behaviour may change to a more graceful handling of this error
2122 * in the future.
2123 */
2124DLLEXPORT int trace_apply_filter(libtrace_filter_t *filter,
2125                const libtrace_packet_t *packet);
2126
2127/** Destroy a BPF filter
2128 * @param filter        The filter to be destroyed
2129 *
2130 * Deallocates all the resources associated with a BPF filter.
2131 */
2132DLLEXPORT void trace_destroy_filter(libtrace_filter_t *filter);
2133/*@}*/
2134
2135/** @name Portability
2136 * This section contains functions that deal with portability issues, e.g. byte
2137 * ordering.
2138 * @{
2139 */
2140
2141/** Converts an ethernet address to a printable string
2142 * @param addr  Ethernet address in network byte order
2143 * @param buf   Buffer to store the ascii representation, or NULL to indicate
2144 * that static storage should be used.
2145 * @return buf, or if buf is NULL then a statically allocated buffer.
2146 *
2147 * This function is similar to the GNU ether_ntoa_r function, with a few
2148 * minor differences.  If NULL is passed as buf, then the function will
2149 * use an internal static buffer. If NULL isn't passed then the function
2150 * will use that buffer instead.
2151 *
2152 * The address pointers returned by trace_get_source_mac() and
2153 * trace_get_destination_mac() can be passed directly into this function.
2154 *
2155 * @note The type of addr isn't struct ether_addr as it is with ether_ntoa_r,
2156 * however it is bit compatible so that a cast will work.
2157 */
2158DLLEXPORT char *trace_ether_ntoa(const uint8_t *addr, char *buf);
2159
2160/** Convert a string to an ethernet address
2161 * @param buf   A string containing an Ethernet address in hex format
2162 * delimited with :'s.
2163 * @param addr  Buffer to store the binary representation, or NULL to indicate
2164 * that static storage should be used.
2165 * @return addr, or if addr is NULL then a statically allocated buffer.
2166 *
2167 * This function is similar to the GNU ether_aton_r function, with a few
2168 * minor differences.  If NULL is passed as addr, then the function will
2169 * use an internal static buffer. If NULL isn't passed then the function will
2170 * use that buffer instead.
2171 *
2172 * The address returned by this function will be in network byte order.
2173 *
2174 * @note the type of addr isn't struct ether_addr as it is with ether_aton_r,
2175 * however it is bit compatible so that a cast will work.
2176 */
2177DLLEXPORT uint8_t *trace_ether_aton(const char *buf, uint8_t *addr);
2178
2179/*@}*/
2180
2181/** @name Ports
2182 * This section contains functions for dealing with port numbers at the
2183 * transport layer.
2184 *
2185 * @{
2186 */
2187
2188/** An indication of which port is the "server" port for a given port pair */
2189typedef enum {
2190        USE_DEST,       /**< Destination port is the server port */
2191        USE_SOURCE      /**< Source port is the server port */
2192} serverport_t;
2193
2194/** Gets the source port for a given packet
2195 * @param packet        The packet to get the source port from
2196 * @return The source port in HOST byte order or 0 if no suitable port number
2197 * can be extracted from the packet.
2198 *
2199 * This function will return 0 if the transport protocol is known not to
2200 * use port numbers, e.g. ICMP. 0 is also returned if no transport header is
2201 * present in the packet or the transport header has been truncated such that
2202 * the port fields are not readable.
2203 *
2204 * @note If the transport protocol is not known by libtrace, the first two
2205 * bytes of the transport header will be treated as the source port field.
2206 */
2207DLLEXPORT SIMPLE_FUNCTION
2208uint16_t trace_get_source_port(const libtrace_packet_t *packet);
2209
2210/** Gets the destination port for a given packet
2211 * @param packet        The packet to get the destination port from
2212 * @return The destination port in HOST byte order or 0 if no suitable port
2213 * number can be extracted from the packet.
2214 *
2215 * This function will return 0 if the transport protocol is known not to
2216 * use port numbers, e.g. ICMP. 0 is also returned if no transport header is
2217 * present in the packet or the transport header has been truncated such that
2218 * the port fields are not readable.
2219 *
2220 * @note If the transport protocol is not known by libtrace, the third and
2221 * fourth bytes of the transport header will be treated as the destination
2222 * port field.
2223 *
2224 */
2225DLLEXPORT SIMPLE_FUNCTION
2226uint16_t trace_get_destination_port(const libtrace_packet_t *packet);
2227
2228/** Hint at which of the two provided ports is the server port.
2229 *
2230 * @param protocol      The IP layer protocol, eg 6 (tcp), 17 (udp)
2231 * @param source        The source port from the packet
2232 * @param dest          The destination port from the packet
2233 *
2234 * @return one of USE_SOURCE or USE_DEST describing on which of the two ports
2235 * is most likely to be the server port.
2236 *
2237 * @note Ports must be provided in HOST byte order!
2238 *
2239 * This function is based almost entirely on heuristics and should not be
2240 * treated as a definitive means of identifying the server port. However, it
2241 * is deterministic, so it is very handy for identifying both halves of the
2242 * same flow.
2243 */
2244DLLEXPORT SIMPLE_FUNCTION
2245int8_t trace_get_server_port(uint8_t protocol, uint16_t source, uint16_t dest);
2246
2247/*@}*/
2248
2249/** @name Wireless trace support
2250 * Functions to access wireless information from packets that have wireless
2251 * monitoring headers such as Radiotap or Prism.
2252 *
2253 * The trace_get_wireless_* functions provide an abstract interface for
2254 * retrieving information from wireless traces. They take a pointer to the
2255 * wireless monitoring header (usually found with trace_get_packet_meta()) and
2256 * the linktype of the header passed in.
2257 *
2258 * All of the trace_get_wireless_* functions return false if the requested
2259 * information was unavailable, or true if it was. The actual data is stored
2260 * in an output variable supplied by the caller. Values returned into the
2261 * output variable will always be returned in host byte order.
2262 * @{
2263 */
2264
2265
2266#ifndef ARPHRD_80211_RADIOTAP
2267/** libc doesn't define this yet, so we have to do so ourselves */
2268#define ARPHRD_80211_RADIOTAP 803
2269#endif
2270
2271/** Get the wireless Timer Synchronisation Function
2272 *
2273 * Gets the value of the timer synchronisation function for this frame, which
2274 * is a value in microseconds indicating the time that the first bit of the
2275 * MPDU was received by the MAC.
2276 *
2277 * @param linkptr The wireless meta header
2278 * @param linktype The linktype of the wireless meta header passed in
2279 * @param[out] tsft The value of the timer synchronisation function.
2280 * @return true if the field was available, false if not.
2281 */
2282DLLEXPORT bool trace_get_wireless_tsft(void *linkptr,
2283        libtrace_linktype_t linktype, uint64_t *tsft);
2284
2285/** Get the wireless data rate
2286 *
2287 * @param linkptr The wireless meta header
2288 * @param linktype The linktype of the wireless meta header passed in
2289 * @param[out] rate The data-rate of the frame in units of 500kbps
2290 * @return true if the field was available, false if not.
2291 */
2292DLLEXPORT bool trace_get_wireless_rate(void *linkptr,
2293        libtrace_linktype_t linktype, uint8_t *rate);
2294
2295/** Get the wireless channel frequency
2296 * @param linkptr The wireless meta header
2297 * @param linktype The linktype of the wireless meta header passed in
2298 * @param[out] freq The frequency in MHz of the channel the frame was
2299 * transmitted or received on.
2300 * @return true if the field was available, false if not.
2301 */
2302DLLEXPORT bool trace_get_wireless_freq(void *linkptr,
2303        libtrace_linktype_t linktype, uint16_t *freq);
2304
2305/** Get the wireless signal strength in dBm
2306 * @param linkptr The wireless meta header
2307 * @param linktype The linktype of the wireless meta header passed in
2308 * @param[out] strength The RF signal power at the antenna, in dB difference
2309 * from 1mW.
2310 * @return true if the field was available, false if not.
2311 */
2312DLLEXPORT bool trace_get_wireless_signal_strength_dbm(void *linkptr,
2313        libtrace_linktype_t linktype, int8_t *strength);
2314
2315/** Get the wireless noise strength in dBm
2316 * @param linkptr The wireless meta header
2317 * @param linktype The linktype of the wireless meta header passed in
2318 * @param[out] strength The RF noise power at the antenna, in dB difference
2319 * from 1mW.
2320 * @return true if the field was available, false if not.
2321 */
2322DLLEXPORT bool trace_get_wireless_noise_strength_dbm(void *linkptr,
2323        libtrace_linktype_t linktype, int8_t *strength);
2324
2325/** Get the wireless signal strength in dB
2326 * @param linkptr The wireless meta header
2327 * @param linktype The linktype of the wireless meta header passed in
2328 * @param[out] strength The RF signal power at the antenna, in dB difference
2329 * from a fixed reference.
2330 * @return true if the field was available, false if not.
2331 */
2332DLLEXPORT bool trace_get_wireless_signal_strength_db(void *linkptr,
2333        libtrace_linktype_t linktype, uint8_t *strength);
2334
2335/** Get the wireless noise strength in dB
2336 * @param linkptr The wireless meta header
2337 * @param linktype The linktype of the wireless meta header passed in
2338 * @param[out] strength The RF noise power at the antenna, in dB difference
2339 * from a fixed reference.
2340 * @return true if the field was available, false if not.
2341 */
2342DLLEXPORT bool trace_get_wireless_noise_strength_db(void *linkptr,
2343        libtrace_linktype_t linktype, uint8_t *strength);
2344
2345/** Get the wireless transmit attenuation
2346 * @param linkptr The wireless meta header
2347 * @param linktype The linktype of the wireless meta header passed in
2348 * @param[out] attenuation The transmit power as a unitless distance from
2349 * maximum power set at factory calibration. 0 indicates maximum transmission
2350 * power.
2351 * @return true if the field was available, false if not.
2352 */
2353DLLEXPORT bool trace_get_wireless_tx_attenuation(void *linkptr,
2354        libtrace_linktype_t linktype, uint16_t *attenuation);
2355
2356/** Get the wireless transmit attenuation in dB
2357 * @param linkptr The wireless meta header
2358 * @param linktype The linktype of the wireless meta header passed in
2359 * @param[out] attenuation The transmit power as dB difference from maximum
2360 * power set at factory calibration. 0 indicates maximum power.
2361 * @return true if the field was available, false if not.
2362 */
2363DLLEXPORT bool trace_get_wireless_tx_attenuation_db(void *linkptr,
2364        libtrace_linktype_t linktype, uint16_t *attenuation);
2365
2366/** Get the wireless transmit power in dBm
2367 * @param linkptr The wireless meta header
2368 * @param linktype The linktype of the wireless meta header passed in
2369 * @param[out] txpower The transmit power as dB from a 1mW reference. This is
2370 * the absolute power level measured at the antenna port. 
2371 * @return true if the field was available, false if not.
2372 */
2373DLLEXPORT bool trace_get_wireless_tx_power_dbm(void *linkptr,
2374                libtrace_linktype_t linktype, int8_t *txpower);
2375
2376/** Get the wireless antenna
2377 * @param linkptr The wireless meta header
2378 * @param linktype The linktype of the wireless meta header passed in
2379 * @param[out] antenna The antenna that was used to transmit or receive the
2380 * frame.
2381 * @return true if the field was available, false if not.
2382 */
2383DLLEXPORT bool trace_get_wireless_antenna(void *linkptr,
2384        libtrace_linktype_t linktype, uint8_t *antenna);
2385
2386/*@}*/
2387
2388#ifdef __cplusplus
2389} /* extern "C" */
2390#endif /* #ifdef __cplusplus */
2391#endif /* LIBTRACE_H_ */
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