diff options
Diffstat (limited to 'packet-isis-lsp.c')
| -rw-r--r-- | packet-isis-lsp.c | 58 |
1 files changed, 46 insertions, 12 deletions
diff --git a/packet-isis-lsp.c b/packet-isis-lsp.c index 4eafc949a9..b75ddf9867 100644 --- a/packet-isis-lsp.c +++ b/packet-isis-lsp.c @@ -1,7 +1,7 @@ /* packet-isis-lsp.c * Routines for decoding isis lsp packets and their CLVs * - * $Id: packet-isis-lsp.c,v 1.42 2003/04/29 16:57:05 guy Exp $ + * $Id: packet-isis-lsp.c,v 1.43 2003/05/15 06:35:02 guy Exp $ * Stuart Stanley <stuarts@mxmail.net> * * Ethereal - Network traffic analyzer @@ -55,6 +55,7 @@ static int hf_isis_lsp_hippity = -1; static int hf_isis_lsp_is_type = -1; static gint ett_isis_lsp = -1; +static gint ett_isis_lsp_checksum = -1; static gint ett_isis_lsp_info = -1; static gint ett_isis_lsp_att = -1; static gint ett_isis_lsp_clv_area_addr = -1; @@ -713,7 +714,12 @@ dissect_lsp_ext_ip_reachability_clv(tvbuff_t *tvb, proto_tree *tree, ctrl_info = tvb_get_guint8(tvb, offset+4); bit_length = ctrl_info & 0x3f; byte_length = (bit_length + 7) / 8; - tvb_memcpy (tvb, prefix, offset+5, byte_length); + if (byte_length > sizeof(prefix)) { + isis_dissect_unknown(tvb, tree, offset, + "IPv4 prefix has an invalid length: %d bytes", byte_length ); + return; + } + tvb_memcpy (tvb, prefix, offset+5, byte_length); metric = tvb_get_ntohl(tvb, offset); subclvs_len = 0; if ((ctrl_info & 0x40) != 0) @@ -806,13 +812,17 @@ dissect_lsp_ipv6_reachability_clv(tvbuff_t *tvb, proto_tree *tree, int offset, if (!tree) return; - memset (prefix.s6_addr, 0, 16); - while (length > 0) { + memset (prefix.s6_addr, 0, 16); ctrl_info = tvb_get_guint8(tvb, offset+4); bit_length = tvb_get_guint8(tvb, offset+5); byte_length = (bit_length + 7) / 8; - tvb_memcpy (tvb, prefix.s6_addr, offset+6, byte_length); + if (byte_length > sizeof(prefix)) { + isis_dissect_unknown(tvb, tree, offset, + "IPv6 prefix has an invalid length: %d bytes", byte_length ); + return; + } + tvb_memcpy (tvb, prefix.s6_addr, offset+6, byte_length); metric = tvb_get_ntohl(tvb, offset); subclvs_len = 0; if ((ctrl_info & 0x20) != 0) @@ -1753,11 +1763,11 @@ void isis_dissect_isis_lsp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset, int lsp_type, int header_length, int id_length) { - proto_item *ti, *to, *ta; - proto_tree *lsp_tree = NULL, *info_tree, *att_tree; - guint16 pdu_length; + proto_item *ti, *to, *ta, *tc; + proto_tree *lsp_tree = NULL, *info_tree, *att_tree, *check_tree; + guint16 pdu_length, checksum, cacl_checksum=0; guint8 lsp_info, lsp_att; - int len; + int len, offset_checksum; if (tree) { ti = proto_tree_add_text(tree, tvb, offset, -1, @@ -1778,6 +1788,7 @@ isis_dissect_isis_lsp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int o tvb_get_ntohs(tvb, offset)); } offset += 2; + offset_checksum = offset; if (tree) { proto_tree_add_text(lsp_tree, tvb, offset, id_length + 2, @@ -1804,9 +1815,31 @@ isis_dissect_isis_lsp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int o offset += 4; if (tree) { - /* XXX -> we could validate the cksum here! */ - proto_tree_add_uint(lsp_tree, hf_isis_lsp_checksum, tvb, - offset, 2, tvb_get_ntohs(tvb, offset)); + checksum = tvb_get_ntohs(tvb, offset); + tc = proto_tree_add_uint(lsp_tree, hf_isis_lsp_checksum, tvb, offset, 2, tvb_get_ntohs(tvb, offset)); + check_tree = proto_item_add_subtree(tc, ett_isis_lsp_checksum); + + switch (check_and_get_checksum(tvb, offset_checksum, pdu_length-12, checksum, offset, &cacl_checksum)) { + case NO_CKSUM : + proto_tree_add_text(check_tree, tvb, offset, 2, + "Checksum control disabled"); + break; + case DATA_MISSING : + isis_dissect_unknown(tvb, tree, offset, + "packet length %d went beyond packet", + tvb_length_remaining(tvb, offset_checksum)); + break; + case CKSUM_NOT_OK : + proto_tree_add_text(check_tree, tvb, offset, 2, + "Checksum error: 0x%04x expected", cacl_checksum); + break; + case CKSUM_OK : + proto_tree_add_text(check_tree, tvb, offset, 2, + "Checksum OK"); + break; + default : + g_message("'check_and_get_checksum' returned an invalid value"); + } } offset += 2; @@ -1932,6 +1965,7 @@ isis_register_lsp(int proto_isis) { }; static gint *ett[] = { &ett_isis_lsp, + &ett_isis_lsp_checksum, &ett_isis_lsp_info, &ett_isis_lsp_att, &ett_isis_lsp_clv_area_addr, |