diff options
| -rw-r--r-- | netsniff-ng.8 | 9 | ||||
| -rw-r--r-- | netsniff-ng.c | 20 |
2 files changed, 24 insertions, 5 deletions
diff --git a/netsniff-ng.8 b/netsniff-ng.8 index b6f129a..748a390 100644 --- a/netsniff-ng.8 +++ b/netsniff-ng.8 @@ -78,10 +78,11 @@ file that should not have the default pcap type (0xa1b2c3d4), the additional option \[lq]\-T\[rq] must be provided. If a directory is given, then, instead of a single pcap file, multiple pcap files are generated with rotation based on maximum file size or a given interval (\[lq]\-F\[rq] option). A trafgen configuration -file can currently only be specified if the input device is a pcap file. If -stdout is given as a device, then a trafgen configuration will be written to -stdout if the input device is a pcap file, or a pcap file if the input device -is a networking device. +file can currently only be specified if the input device is a pcap file. To +specify a pcap file as the output device, the file name must have +\[lq].pcap\[rq] as its extension. If stdout is given as a device, then a trafgen +configuration will be written to stdout if the input device is a pcap file, or a +pcap file if the input device is a networking device. .PP .SS -f, --filter <bpf-file|expr> Specifies to not dump all traffic, but to filter the network packet haystack. diff --git a/netsniff-ng.c b/netsniff-ng.c index 477c81d..5477257 100644 --- a/netsniff-ng.c +++ b/netsniff-ng.c @@ -528,6 +528,8 @@ static void read_pcap(struct ctx *ctx) struct sock_fprog bpf_ops; struct frame_map fm; struct timeval start, end, diff; + bool is_out_pcap = ctx->device_out && strstr(ctx->device_out, ".pcap"); + const struct pcap_file_ops *pcap_out_ops = pcap_ops[PCAP_OPS_RW]; bug_on(!__pcap_io); @@ -574,6 +576,13 @@ static void read_pcap(struct ctx *ctx) } } + if (is_out_pcap) { + ret = pcap_out_ops->push_fhdr_pcap(fdo, ctx->magic, + ctx->link_type); + if (ret) + panic("Error writing pcap header!\n"); + } + drop_privileges(ctx->enforce, ctx->uid, ctx->gid); printf("Running! Hang up with ^C!\n\n"); @@ -612,8 +621,16 @@ static void read_pcap(struct ctx *ctx) dissector_entry_point(out, fm.tp_h.tp_snaplen, ctx->link_type, ctx->print_mode); - if (ctx->device_out) + if (is_out_pcap) { + size_t pcap_len = pcap_get_length(&phdr, ctx->magic); + int wlen = pcap_out_ops->write_pcap(fdo, &phdr, + ctx->magic, out, + pcap_len); + if (unlikely(wlen != (int)pcap_get_total_length(&phdr, ctx->magic))) + panic("Error writing to pcap!\n"); + } else if (ctx->device_out) { translate_pcap_to_txf(fdo, out, fm.tp_h.tp_snaplen); + } if (frame_count_max != 0) { if (ctx->tx_packets >= frame_count_max) { @@ -1132,6 +1149,7 @@ static void __noreturn help(void) " netsniff-ng --in wlan0 --rfraw --out dump.pcap --silent --bind-cpu 0\n" " netsniff-ng --in dump.pcap --mmap --out eth0 -k1000 --silent --bind-cpu 0\n" " netsniff-ng --in dump.pcap --out dump.cfg --silent --bind-cpu 0\n" + " netsniff-ng --in dump.pcap --out dump2.pcap --silent tcp\n" " netsniff-ng --in eth0 --out eth1 --silent --bind-cpu 0 -J --type host\n" " netsniff-ng --in eth1 --out /opt/probe/ -s -m --interval 100MiB -b 0\n" " netsniff-ng --in vlan0 --out dump.pcap -c -u `id -u bob` -g `id -g bob`\n" |