diff options
| author | Christopher Pascoe <pascoe@cvs.openbsd.org> | 2004-12-20 08:30:41 +0000 |
|---|---|---|
| committer | Christopher Pascoe <pascoe@cvs.openbsd.org> | 2004-12-20 08:30:41 +0000 |
| commit | c6e78b160bb0e446bb146be6b8b66890b48e5b31 (patch) | |
| tree | 1e0e4e54f97961ea95dacfafabf2d45272b07a4e /usr.sbin/tcpdump/print-stp.c | |
| parent | 727f4d6da89be1e49e601d5f0d4c77b24631bca8 (diff) | |
Add support for displaying Shared Spanning Tree Protocol frames, a minor
variation on 802.1d/STP.
ok otto@ mcbride@
Diffstat (limited to 'usr.sbin/tcpdump/print-stp.c')
| -rw-r--r-- | usr.sbin/tcpdump/print-stp.c | 32 |
1 files changed, 26 insertions, 6 deletions
diff --git a/usr.sbin/tcpdump/print-stp.c b/usr.sbin/tcpdump/print-stp.c index 81068541249..7a321f67684 100644 --- a/usr.sbin/tcpdump/print-stp.c +++ b/usr.sbin/tcpdump/print-stp.c @@ -1,4 +1,4 @@ -/* $OpenBSD: print-stp.c,v 1.3 2003/06/03 00:21:04 jason Exp $ */ +/* $OpenBSD: print-stp.c,v 1.4 2004/12/20 08:30:40 pascoe Exp $ */ /* * Copyright (c) 2000 Jason L. Wright (jason@thought.net) @@ -68,7 +68,7 @@ struct rtentry; #define STP_FLAGS_TC 0x01 /* Topology change */ #define STP_FLAGS_TCA 0x80 /* Topology change ack */ -static void stp_print_cbpdu(const u_char *, u_int); +static void stp_print_cbpdu(const u_char *, u_int, int); static void stp_print_tbpdu(const u_char *, u_int); void @@ -77,14 +77,21 @@ stp_print(p, len) u_int len; { u_int16_t id; + int cisco_sstp = 0; if (len < 3) goto truncated; - if (p[0] != LLCSAP_8021D || p[1] != LLCSAP_8021D || p[2] != LLC_UI) { + if (p[0] == LLCSAP_8021D && p[1] == LLCSAP_8021D && p[2] == LLC_UI) + printf("802.1d"); + else if (p[0] == LLCSAP_SNAP && p[1] == LLCSAP_SNAP && p[2] == LLC_UI) { + cisco_sstp = 1; + printf("SSTP"); + p += 5; + len -= 5; + } else { printf("invalid protocol"); return; } - printf("802.1d"); p += 3; len -= 3; @@ -106,7 +113,7 @@ stp_print(p, len) goto truncated; switch (*p) { case STP_MSGTYPE_CBPDU: - stp_print_cbpdu(p, len); + stp_print_cbpdu(p, len, cisco_sstp); break; case STP_MSGTYPE_TBPDU: stp_print_tbpdu(p, len); @@ -123,9 +130,10 @@ truncated: } static void -stp_print_cbpdu(p, len) +stp_print_cbpdu(p, len, cisco_sstp) const u_char *p; u_int len; + int cisco_sstp; { u_int32_t cost; u_int16_t t; @@ -213,6 +221,18 @@ stp_print_cbpdu(p, len) p += 2; len -= 2; + if (cisco_sstp) { + if (len < 7) + goto truncated; + p += 1; + len -= 1; + if (EXTRACT_16BITS(p) == 0 && EXTRACT_16BITS(p + 2) == 0x02) { + printf(" pvid=%u", EXTRACT_16BITS(p + 4)); + p += 6; + len -= 6; + } + } + return; truncated: |