diff options
Diffstat (limited to 'epan/packet.c')
| -rw-r--r-- | epan/packet.c | 75 |
1 files changed, 64 insertions, 11 deletions
diff --git a/epan/packet.c b/epan/packet.c index 5e378880d0..9866f47174 100644 --- a/epan/packet.c +++ b/epan/packet.c @@ -1932,15 +1932,16 @@ heur_dissector_set_enabled(const char *name, heur_dissector_t dissector, const i gboolean dissector_try_heuristic(heur_dissector_list_t sub_dissectors, tvbuff_t *tvb, - packet_info *pinfo, proto_tree *tree, void *data) + packet_info *pinfo, proto_tree *tree, heur_dtbl_entry_t **heur_dtbl_entry, void *data) { gboolean status; const char *saved_curr_proto; const char *saved_heur_list_name; GSList *entry; - heur_dtbl_entry_t *hdtbl_entry; guint16 saved_can_desegment; guint saved_layers_len = 0; + heur_dtbl_entry_t *hdtbl_entry; + int proto_id; /* can_desegment is set to 2 by anyone which offers this api/service. then everytime a subdissector is called it is decremented by one. @@ -1960,6 +1961,7 @@ dissector_try_heuristic(heur_dissector_list_t sub_dissectors, tvbuff_t *tvb, saved_heur_list_name = pinfo->heur_list_name; saved_layers_len = wmem_list_count(pinfo->layers); + *heur_dtbl_entry = NULL; for (entry = sub_dissectors; entry != NULL; entry = g_slist_next(entry)) { /* XXX - why set this now and above? */ @@ -1967,13 +1969,14 @@ dissector_try_heuristic(heur_dissector_list_t sub_dissectors, tvbuff_t *tvb, hdtbl_entry = (heur_dtbl_entry_t *)entry->data; if (hdtbl_entry->protocol != NULL && - (!proto_is_protocol_enabled(hdtbl_entry->protocol)||(hdtbl_entry->enabled==FALSE))) { + (!proto_is_protocol_enabled(hdtbl_entry->protocol)||(hdtbl_entry->enabled==FALSE))) { /* * No - don't try this dissector. */ continue; } + proto_id = proto_get_id(hdtbl_entry->protocol); if (hdtbl_entry->protocol != NULL) { /* do NOT change this behavior - wslua uses the protocol short name set here in order to determine which Lua-based heurisitc dissector to call */ @@ -1984,21 +1987,19 @@ dissector_try_heuristic(heur_dissector_list_t sub_dissectors, tvbuff_t *tvb, * Add the protocol name to the layers; we'll remove it * if the dissector fails. */ - wmem_list_append(pinfo->layers, GINT_TO_POINTER(proto_get_id(hdtbl_entry->protocol))); + wmem_list_append(pinfo->layers, GINT_TO_POINTER(proto_id)); } pinfo->heur_list_name = hdtbl_entry->list_name; - EP_CHECK_CANARY(("before calling heuristic dissector for protocol: %s", - proto_get_protocol_filter_name(proto_get_id(hdtbl_entry->protocol)))); - if ((*hdtbl_entry->dissector)(tvb, pinfo, tree, data)) { - EP_CHECK_CANARY(("after heuristic dissector for protocol: %s has accepted and dissected packet", - proto_get_protocol_filter_name(proto_get_id(hdtbl_entry->protocol)))); + EP_CHECK_CANARY(("before calling heuristic dissector for protocol: %s", proto_get_protocol_filter_name(proto_id))); + if ((hdtbl_entry->dissector)(tvb, pinfo, tree, data)) { + EP_CHECK_CANARY(("after heuristic dissector for protocol: %s has accepted and dissected packet", proto_get_protocol_filter_name(proto_id))); + *heur_dtbl_entry = hdtbl_entry; status = TRUE; break; } else { - EP_CHECK_CANARY(("after heuristic dissector for protocol: %s has returned false", - proto_get_protocol_filter_name(proto_get_id(hdtbl_entry->protocol)))); + EP_CHECK_CANARY(("after heuristic dissector for protocol: %s has returned false", proto_get_protocol_filter_name(proto_id))); /* * That dissector didn't accept the packet, so @@ -2281,6 +2282,58 @@ call_dissector(dissector_handle_t handle, tvbuff_t *tvb, return call_dissector_with_data(handle, tvb, pinfo, tree, NULL); } + +/* + * Call a heuristic dissector through a heur_dtbl_entry + */ +void call_heur_dissector_direct(heur_dtbl_entry_t *heur_dtbl_entry, tvbuff_t *tvb, + packet_info *pinfo, proto_tree *tree, void *data) +{ + const char *saved_curr_proto; + const char *saved_heur_list_name; + guint16 saved_can_desegment; + + int proto_id; + + g_assert(heur_dtbl_entry); + + /* can_desegment is set to 2 by anyone which offers this api/service. + then everytime a subdissector is called it is decremented by one. + thus only the subdissector immediately ontop of whoever offers this + service can use it. + We save the current value of "can_desegment" for the + benefit of TCP proxying dissectors such as SOCKS, so they + can restore it and allow the dissectors they call to use + the desegmentation service. + */ + saved_can_desegment = pinfo->can_desegment; + pinfo->saved_can_desegment = saved_can_desegment; + pinfo->can_desegment = saved_can_desegment-(saved_can_desegment>0); + + saved_curr_proto = pinfo->current_proto; + saved_heur_list_name = pinfo->heur_list_name; + + proto_id = proto_get_id(heur_dtbl_entry->protocol); + + if (heur_dtbl_entry->protocol != NULL) { + /* do NOT change this behavior - wslua uses the protocol short name set here in order + to determine which Lua-based heurisitc dissector to call */ + pinfo->current_proto = proto_get_protocol_short_name(heur_dtbl_entry->protocol); + wmem_list_append(pinfo->layers, GINT_TO_POINTER(proto_id)); + } + + EP_CHECK_CANARY(("before calling heuristic dissector for protocol: %s", proto_get_protocol_filter_name(proto_id))); + + /* call the dissector, as we have saved the result heuristic failure is an error */ + if(!(*heur_dtbl_entry->dissector)(tvb, pinfo, tree, data)) + g_assert_not_reached(); + + /* Restore info from caller */ + pinfo->can_desegment = saved_can_desegment; + pinfo->current_proto = saved_curr_proto; + pinfo->heur_list_name = saved_heur_list_name; + +} /* * Dumps the "layer type"/"decode as" associations to stdout, similar * to the proto_registrar_dump_*() routines. |