osmocom
/
wireshark
14
0
Fork 1
Code Issues Pull Requests Projects Releases Wiki Activity

From Erik Bray: 

Incorrect dissasembly of IPv6 packets with extension headers after the fragment header

svn path=/trunk/; revision=25882
This commit is contained in:
Anders Broman 2008-07-31 09:22:22 +00:00
parent 6858fbdbf3
commit b95bfb9503
1 changed files with 42 additions and 50 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

92
epan/dissectors/packet-ipv6.c
View File

@ -1247,7 +1247,7 @@ dissect_ipv6(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
fragment_data *ipfd_head;
tvbuff_t *next_tvb;
gboolean update_col_info = TRUE;
gboolean save_fragmented;
gboolean save_fragmented = FALSE;
const char *sep = "IPv6 ";
struct ip6_hdr ipv6;
@ -1376,15 +1376,35 @@ again:
offset += advance;
plen -= advance;
goto again;
case IP_PROTO_FRAGMENT:
frag = TRUE;
case IP_PROTO_FRAGMENT:
advance = dissect_frag6(tvb, offset, pinfo, ipv6_tree,
&offlg, &ident);
nxt = tvb_get_guint8(tvb, offset);
poffset = offset;
offset += advance;
plen -= advance;
goto again;
frag = offlg & (IP6F_OFF_MASK | IP6F_MORE_FRAG);
save_fragmented |= frag;
if (ipv6_reassemble && frag && tvb_bytes_exist(tvb, offset, plen)) {
ipfd_head = fragment_add_check(tvb, offset, pinfo, ident,
ipv6_fragment_table,
ipv6_reassembled_table,
offlg & IP6F_OFF_MASK,
plen,
offlg & IP6F_MORE_FRAG);
next_tvb = process_reassembled_data(tvb, offset, pinfo, "Reassembled IPv6",
ipfd_head, &ipv6_frag_items, &update_col_info, ipv6_tree);
if (next_tvb) { /* Process post-fragment headers after reassembly... */
offset= 0;
offlg = 0;
frag = FALSE;
tvb = next_tvb;
goto again;
}
}
if (!(offlg & IP6F_OFF_MASK)) /*...or in the first fragment */
goto again;
break;
case IP_PROTO_AH:
ah = TRUE;
advance = dissect_ah_header(
@ -1424,57 +1444,29 @@ again:
pinfo->iplen = sizeof(ipv6) + plen + offset;
pinfo->iphdrlen = offset;
/* If ipv6_reassemble is on, this is a fragment, and we have all the data
* in the fragment, then just add the fragment to the hashtable.
*/
save_fragmented = pinfo->fragmented;
if (ipv6_reassemble && frag && tvb_bytes_exist(tvb, offset, plen)) {
ipfd_head = fragment_add_check(tvb, offset, pinfo, ident,
ipv6_fragment_table,
ipv6_reassembled_table,
offlg & IP6F_OFF_MASK,
plen,
offlg & IP6F_MORE_FRAG);
next_tvb = process_reassembled_data(tvb, offset, pinfo, "Reassembled IPv6",
ipfd_head, &ipv6_frag_items, &update_col_info, ipv6_tree);
} else {
/* If this is the first fragment, dissect its contents, otherwise
just show it as a fragment.
XXX - if we eventually don't save the reassembled contents of all
fragmented datagrams, we may want to always reassemble. */
if (offlg & IP6F_OFF_MASK) {
/* Not the first fragment - don't dissect it. */
next_tvb = NULL;
} else {
/* First fragment, or not fragmented. Dissect what we have here. */
/* Get a tvbuff for the payload. */
next_tvb = tvb_new_subset(tvb, offset, -1, -1);
/*
* If this is the first fragment, but not the only fragment,
* tell the next protocol that.
*/
if (offlg & IP6F_MORE_FRAG)
pinfo->fragmented = TRUE;
else
pinfo->fragmented = FALSE;
}
}
if (next_tvb == NULL) {
/* Just show this as a fragment. */
if (offlg & IP6F_OFF_MASK || (ipv6_reassemble && offlg & IP6F_MORE_FRAG)) {
/* Not the first fragment, or the first when we are reassembling and there are more. */
/* Don't dissect it; just show this as a fragment. */
/* COL_INFO was filled in by "dissect_frag6()" */
call_dissector(data_handle, tvb_new_subset(tvb, offset, -1, -1), pinfo, tree);
/* As we haven't reassembled anything, we haven't changed "pi", so
we don't have to restore it. */
pinfo->fragmented = save_fragmented;
return;
} else {
/* First fragment, not fragmented, or already reassembled. Dissect what we have here. */
/* Get a tvbuff for the payload. */
next_tvb = tvb_new_subset(tvb, offset, -1, -1);
/*
* If this is the first fragment, but not the only fragment,
* tell the next protocol that.
*/
if (offlg & IP6F_MORE_FRAG)
pinfo->fragmented = TRUE;
else
pinfo->fragmented = FALSE;
}
/* do lookup with the subdissector table */
if (!dissector_try_port(ip_dissector_table, nxt, next_tvb, pinfo, tree)) {
/* Unknown protocol.