diff options
Diffstat (limited to 'lib/pcap-file.c')
| -rw-r--r-- | lib/pcap-file.c | 102 |
1 files changed, 71 insertions, 31 deletions
diff --git a/lib/pcap-file.c b/lib/pcap-file.c index ea5cfa3b2..81a094c2a 100644 --- a/lib/pcap-file.c +++ b/lib/pcap-file.c @@ -34,6 +34,16 @@ VLOG_DEFINE_THIS_MODULE(pcap); +enum ts_resolution { + PCAP_USEC, + PCAP_NSEC, +}; + +struct pcap_file { + FILE *file; + enum ts_resolution resolution; +}; + struct pcap_hdr { uint32_t magic_number; /* magic number */ uint16_t version_major; /* major version number */ @@ -47,25 +57,27 @@ BUILD_ASSERT_DECL(sizeof(struct pcap_hdr) == 24); struct pcaprec_hdr { uint32_t ts_sec; /* timestamp seconds */ - uint32_t ts_usec; /* timestamp microseconds */ + uint32_t ts_subsec; /* timestamp subseconds */ uint32_t incl_len; /* number of octets of packet saved in file */ uint32_t orig_len; /* actual length of packet */ }; BUILD_ASSERT_DECL(sizeof(struct pcaprec_hdr) == 16); -FILE * +struct pcap_file * ovs_pcap_open(const char *file_name, const char *mode) { struct stat s; - FILE *file; + struct pcap_file *p_file; int error; ovs_assert(!strcmp(mode, "rb") || !strcmp(mode, "wb") || !strcmp(mode, "ab")); - file = fopen(file_name, mode); - if (file == NULL) { + p_file = xmalloc(sizeof *p_file); + p_file->file = fopen(file_name, mode); + p_file->resolution = PCAP_USEC; + if (p_file->file == NULL) { VLOG_WARN("%s: failed to open pcap file for %s (%s)", file_name, (mode[0] == 'r' ? "reading" : mode[0] == 'w' ? "writing" @@ -76,49 +88,64 @@ ovs_pcap_open(const char *file_name, const char *mode) switch (mode[0]) { case 'r': - error = ovs_pcap_read_header(file); + error = ovs_pcap_read_header(p_file); if (error) { errno = error; - fclose(file); + ovs_pcap_close(p_file); return NULL; } break; case 'w': - ovs_pcap_write_header(file); + ovs_pcap_write_header(p_file); break; case 'a': - if (!fstat(fileno(file), &s) && !s.st_size) { - ovs_pcap_write_header(file); + if (!fstat(fileno(p_file->file), &s) && !s.st_size) { + ovs_pcap_write_header(p_file); } break; default: OVS_NOT_REACHED(); } - return file; + + return p_file; +} + +struct pcap_file * +ovs_pcap_stdout(void) +{ + struct pcap_file *p_file = xmalloc(sizeof *p_file); + p_file->file = stdout; + return p_file; } int -ovs_pcap_read_header(FILE *file) +ovs_pcap_read_header(struct pcap_file *p_file) { struct pcap_hdr ph; - if (fread(&ph, sizeof ph, 1, file) != 1) { - int error = ferror(file) ? errno : EOF; + if (fread(&ph, sizeof ph, 1, p_file->file) != 1) { + int error = ferror(p_file->file) ? errno : EOF; VLOG_WARN("failed to read pcap header: %s", ovs_retval_to_string(error)); return error; } - if (ph.magic_number != 0xa1b2c3d4 && ph.magic_number != 0xd4c3b2a1) { + if (ph.magic_number == 0xa1b2c3d4 || ph.magic_number == 0xd4c3b2a1) { + p_file->resolution = PCAP_USEC; + } else if (ph.magic_number == 0xa1b23c4d || + ph.magic_number == 0x4d3cb2a1) { + p_file->resolution = PCAP_NSEC; + } else { VLOG_WARN("bad magic 0x%08"PRIx32" reading pcap file " - "(expected 0xa1b2c3d4 or 0xd4c3b2a1)", ph.magic_number); + "(expected 0xa1b2c3d4, 0xa1b23c4d, 0xd4c3b2a1, " + "or 0x4d3cb2a1)", ph.magic_number); return EPROTO; } return 0; } void -ovs_pcap_write_header(FILE *file) +ovs_pcap_write_header(struct pcap_file *p_file) { /* The pcap reader is responsible for figuring out endianness based on the * magic number, so the lack of htonX calls here is intentional. */ @@ -130,12 +157,13 @@ ovs_pcap_write_header(FILE *file) ph.sigfigs = 0; ph.snaplen = 1518; ph.network = 1; /* Ethernet */ - ignore(fwrite(&ph, sizeof ph, 1, file)); - fflush(file); + ignore(fwrite(&ph, sizeof ph, 1, p_file->file)); + fflush(p_file->file); } int -ovs_pcap_read(FILE *file, struct dp_packet **bufp, long long int *when) +ovs_pcap_read(struct pcap_file *p_file, struct dp_packet **bufp, + long long int *when) { struct pcaprec_hdr prh; struct dp_packet *buf; @@ -146,8 +174,8 @@ ovs_pcap_read(FILE *file, struct dp_packet **bufp, long long int *when) *bufp = NULL; /* Read header. */ - if (fread(&prh, sizeof prh, 1, file) != 1) { - if (ferror(file)) { + if (fread(&prh, sizeof prh, 1, p_file->file) != 1) { + if (ferror(p_file->file)) { int error = errno; VLOG_WARN("failed to read pcap record header: %s", ovs_retval_to_string(error)); @@ -173,15 +201,18 @@ ovs_pcap_read(FILE *file, struct dp_packet **bufp, long long int *when) /* Calculate time. */ if (when) { uint32_t ts_sec = swap ? uint32_byteswap(prh.ts_sec) : prh.ts_sec; - uint32_t ts_usec = swap ? uint32_byteswap(prh.ts_usec) : prh.ts_usec; - *when = ts_sec * 1000LL + ts_usec / 1000; + uint32_t ts_subsec = swap ? uint32_byteswap(prh.ts_subsec) + : prh.ts_subsec; + ts_subsec = p_file->resolution == PCAP_USEC ? ts_subsec / 1000 + : ts_subsec / 1000000; + *when = ts_sec * 1000LL + ts_subsec; } /* Read packet. Packet type is Ethernet */ buf = dp_packet_new(len); data = dp_packet_put_uninit(buf, len); - if (fread(data, len, 1, file) != 1) { - int error = ferror(file) ? errno : EOF; + if (fread(data, len, 1, p_file->file) != 1) { + int error = ferror(p_file->file) ? errno : EOF; VLOG_WARN("failed to read pcap packet: %s", ovs_retval_to_string(error)); dp_packet_delete(buf); @@ -192,7 +223,7 @@ ovs_pcap_read(FILE *file, struct dp_packet **bufp, long long int *when) } void -ovs_pcap_write(FILE *file, struct dp_packet *buf) +ovs_pcap_write(struct pcap_file *p_file, struct dp_packet *buf) { struct pcaprec_hdr prh; struct timeval tv; @@ -201,12 +232,21 @@ ovs_pcap_write(FILE *file, struct dp_packet *buf) xgettimeofday(&tv); prh.ts_sec = tv.tv_sec; - prh.ts_usec = tv.tv_usec; + prh.ts_subsec = tv.tv_usec; prh.incl_len = dp_packet_size(buf); prh.orig_len = dp_packet_size(buf); - ignore(fwrite(&prh, sizeof prh, 1, file)); - ignore(fwrite(dp_packet_data(buf), dp_packet_size(buf), 1, file)); - fflush(file); + ignore(fwrite(&prh, sizeof prh, 1, p_file->file)); + ignore(fwrite(dp_packet_data(buf), dp_packet_size(buf), 1, p_file->file)); + fflush(p_file->file); +} + +void +ovs_pcap_close(struct pcap_file *p_file) +{ + if (p_file->file != stdout) { + fclose(p_file->file); + } + free(p_file); } struct tcp_key { |