Changeset a464de7

Timestamp:

12/04/12 17:11:00 (9 years ago)

Author:

Shane Alcock <salcock@…>

Branches:

4.0.1-hotfixes, cachetimestamps, develop, dpdk-ndag, etsilive, getfragoff, help, libtrace4, master, ndag_format, pfring, rc-4.0.1, rc-4.0.2, rc-4.0.3, rc-4.0.4, ringdecrementfix, ringperformance, ringtimestampfixes

Children:

6ba84d9

Parents:

b4c3f61

Message:

• Linux machines will now be able to successfully decode traffic captured using bpf

Location:

lib

Files:

• Makefile.am (modified) (1 diff)
• format_bpf.c (modified) (7 diffs)
• trace.c (modified) (1 diff)

lib/Makefile.am

@@ -7 +7 @@
 extra_DIST = format_template.c
 NATIVEFORMATS=format_linux.c
-
-if HAVE_BPF_CAPTURE
 BPFFORMATS=format_bpf.c
-else
-BPFFORMATS=
-endif
 
 if HAVE_DAG

lib/format_bpf.c

@@ -68 +68 @@
  */ 
 
+struct bpf_timeval {
+        uint32_t tv_sec;
+        uint32_t tv_usec;
+};
+
+struct libtrace_bpf_hdr {
+        struct bpf_timeval bh_tstamp;   /* timestamp */
+        uint32_t bh_caplen;             /* capture length */
+        uint32_t bh_datalen;            /* wire length */
+        uint16_t bh_hdrlen;             /* header length (incl padding) */
+};
+
+#define BPFHDR(x) ((struct libtrace_bpf_hdr *)((x)->header))
+
+#if HAVE_DECL_BIOCSETIF
 /* "Global" data that is stored for each BPF input trace */
 struct libtrace_format_data_t {
@@ -95 +110 @@
 #define FORMATIN(x) ((struct libtrace_format_data_t*)((x->format_data)))
 
-#define BPFHDR(x) ((struct bpf_hdr *)((x)->header))
 
 /* Attempts to determine if a given filename could refer to a BPF interface */
@@ -340 +354 @@
 }
 
+#endif  /* HAVE_DECL_BIOCSETIF */
+
 /* Converts a buffer containing a recently read BPF packet record into a
  * libtrace packet */
-static int bpf_prepare_packet(libtrace_t *libtrace, libtrace_packet_t *packet,
+static int bpf_prepare_packet(libtrace_t *libtrace UNUSED, 
+                libtrace_packet_t *packet,
                 void *buffer, libtrace_rt_types_t rt_type, uint32_t flags) {
         
@@ -368 +385 @@
         packet->payload=(char *)buffer + BPFHDR(packet)->bh_hdrlen;
 
+        /*
         if (libtrace->format_data == NULL) {
                 if (bpf_init_input(libtrace))
                         return -1;
         }
+        */
 
         return 0;
 }
+
+#if HAVE_DECL_BIOCSETIF
 
 /* Reads the next packet record from a BPF interface and writes it into a 
@@ -434 +455 @@
 }
 
+#endif  /* HAVE_DECL_BIOCSETIF */
+
 /* Returns the linktype for the interface that we are capturing from */
 static libtrace_linktype_t bpf_get_link_type(const libtrace_packet_t *packet) {
@@ -485 +508 @@
 }
 
+#if HAVE_DECL_BIOCSETIF
 /* Returns the file descriptor that the capture interface is operating on */
 static int bpf_get_fd(const libtrace_t *trace) {
@@ -540 +564 @@
         NULL
 };
+#else   /* HAVE_DECL_BIOCSETIF */
+/* Prints some slightly useful help text for the BPF capture format */
+static void bpf_help() {
+        printf("bpf format module: $Revision$\n");
+        printf("Not supported on this host\n");
+        return;
+}
+static struct libtrace_format_t bpf = {
+        "bpf",
+        "$Id$",
+        TRACE_FORMAT_BPF,
+        NULL,                   /* probe filename */
+        NULL,                   /* probe magic */
+        NULL,                   /* init_input */
+        NULL,                   /* config_input */
+        NULL,                   /* start_input */
+        NULL,                   /* pause_input */
+        NULL,                   /* init_output */
+        NULL,                   /* config_output */
+        NULL,                   /* start_ouput */
+        NULL,                   /* fin_input */
+        NULL,                   /* fin_output */
+        NULL,                   /* read_packet */
+        bpf_prepare_packet,     /* prepare_packet */
+        NULL,                   /* fin_packet */
+        NULL,                   /* write_packet */
+        bpf_get_link_type,      /* get_link_type */
+        bpf_get_direction,      /* get_direction */
+        NULL,                   /* set_direction */
+        NULL,                   /* get_erf_timestamp */
+        bpf_get_timeval,        /* get_timeval */
+        NULL,                   /* get_timespec */
+        NULL,                   /* get_seconds */
+        NULL,                   /* seek_erf */
+        NULL,                   /* seek_timeval */
+        NULL,                   /* seek_seconds */
+        bpf_get_capture_length, /* get_capture_length */
+        bpf_get_wire_length,    /* get_wire_length */
+        bpf_get_framing_length, /* get_framing_length */
+        NULL,                   /* set_capture_length */
+        NULL,/* get_received_packets */
+        NULL,                   /* get_filtered_packets */
+        NULL,/* get_dropped_packets */
+        NULL,                   /* get_captured_packets */
+        NULL,                   /* get_fd */
+        NULL,                   /* trace_event */
+        bpf_help,               /* help */
+        NULL
+};
+#endif  /* HAVE_DECL_BIOCSETIF */
 
 void bpf_constructor() {

lib/trace.c

@@ -140 +140 @@
                 pcap_constructor();
 #endif
-#if HAVE_DECL_BIOCSETIF
                 bpf_constructor();
-#endif
                 pcapfile_constructor();
                 rt_constructor();