/* packet-websocket.c
* Routines for WebSocket dissection
* Copyright 2012, Alexis La Goutte <alexis.lagoutte@gmail.com>
+ * 2015, Peter Wu <peter@lekensteyn.nl>
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
* Copyright 1998 Gerald Combs
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc.,
- * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ * SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "config.h"
-#include <glib.h>
-
+#include <epan/conversation.h>
+#include <epan/proto_data.h>
#include <epan/packet.h>
#include <epan/expert.h>
#include <epan/prefs.h>
+#include <wsutil/strtoi.h>
+
+#include "packet-http.h"
+#include "packet-tcp.h"
+#ifdef HAVE_ZLIB
+#define ZLIB_CONST
+#include <zlib.h>
+#endif
/*
* The information used comes from:
void proto_register_websocket(void);
void proto_reg_handoff_websocket(void);
+static dissector_handle_t websocket_handle;
static dissector_handle_t text_lines_handle;
static dissector_handle_t json_handle;
static dissector_handle_t sip_handle;
#define WEBSOCKET_SIP 3
static gint pref_text_type = WEBSOCKET_NONE;
+static gboolean pref_decompress = TRUE;
+
+typedef struct {
+ const char *subprotocol;
+ guint16 server_port;
+ gboolean permessage_deflate;
+#ifdef HAVE_ZLIB
+ gboolean permessage_deflate_ok;
+ gint8 server_wbits;
+ gint8 client_wbits;
+ z_streamp server_take_over_context;
+ z_streamp client_take_over_context;
+#endif
+} websocket_conv_t;
+
+#ifdef HAVE_ZLIB
+typedef struct {
+ guint8 *decompr_payload;
+ guint decompr_len;
+} websocket_packet_t;
+#endif
/* Initialize the protocol and registered fields */
static int proto_websocket = -1;
+static int proto_http = -1;
+
static int hf_ws_fin = -1;
static int hf_ws_reserved = -1;
+static int hf_ws_pmc = -1;
static int hf_ws_opcode = -1;
static int hf_ws_mask = -1;
static int hf_ws_payload_length = -1;
static int hf_ws_payload_length_ext_64 = -1;
static int hf_ws_masking_key = -1;
static int hf_ws_payload = -1;
-static int hf_ws_payload_unmask = -1;
+static int hf_ws_masked_payload = -1;
static int hf_ws_payload_continue = -1;
-static int hf_ws_payload_text = -1;
-static int hf_ws_payload_text_mask = -1;
-static int hf_ws_payload_text_unmask = -1;
-static int hf_ws_payload_binary = -1;
-static int hf_ws_payload_binary_mask = -1;
-static int hf_ws_payload_binary_unmask = -1;
static int hf_ws_payload_close = -1;
-static int hf_ws_payload_close_mask = -1;
-static int hf_ws_payload_close_unmask = -1;
static int hf_ws_payload_close_status_code = -1;
static int hf_ws_payload_close_reason = -1;
static int hf_ws_payload_ping = -1;
-static int hf_ws_payload_ping_mask = -1;
-static int hf_ws_payload_ping_unmask = -1;
static int hf_ws_payload_pong = -1;
-static int hf_ws_payload_pong_mask = -1;
-static int hf_ws_payload_pong_unmask = -1;
static int hf_ws_payload_unknown = -1;
static gint ett_ws = -1;
static gint ett_ws_pl = -1;
static gint ett_ws_mask = -1;
+static gint ett_ws_control_close = -1;
static expert_field ei_ws_payload_unknown = EI_INIT;
+static expert_field ei_ws_decompression_failed = EI_INIT;
#define WS_CONTINUE 0x0
#define WS_TEXT 0x1
#define MASK_WS_FIN 0x80
#define MASK_WS_RSV 0x70
+#define MASK_WS_RSV1 0x40
#define MASK_WS_OPCODE 0x0F
#define MASK_WS_MASK 0x80
#define MASK_WS_PAYLOAD_LEN 0x7F
};
static dissector_table_t port_subdissector_table;
+static dissector_table_t protocol_subdissector_table;
static heur_dissector_list_t heur_subdissector_list;
-#define MAX_UNMASKED_LEN (1024 * 64)
+#define MAX_UNMASKED_LEN (1024 * 256)
static tvbuff_t *
-tvb_unmasked(tvbuff_t *tvb, const guint offset, guint payload_length, const guint8 *masking_key)
+tvb_unmasked(tvbuff_t *tvb, packet_info *pinfo, const guint offset, guint payload_length, const guint8 *masking_key)
{
gchar *data_unmask;
- tvbuff_t *tvb_unmask = NULL;
guint i;
const guint8 *data_mask;
guint unmasked_length = payload_length > MAX_UNMASKED_LEN ? MAX_UNMASKED_LEN : payload_length;
- data_unmask = (gchar *)g_malloc(unmasked_length);
+ data_unmask = (gchar *)wmem_alloc(pinfo->pool, unmasked_length);
data_mask = tvb_get_ptr(tvb, offset, unmasked_length);
/* Unmasked(XOR) Data... */
for(i=0; i < unmasked_length; i++) {
data_unmask[i] = data_mask[i] ^ masking_key[i%4];
}
- tvb_unmask = tvb_new_real_data(data_unmask, unmasked_length, unmasked_length);
- tvb_set_free_cb(tvb_unmask, g_free);
- return tvb_unmask;
+ return tvb_new_real_data(data_unmask, unmasked_length, payload_length);
}
-static int
-dissect_websocket_payload(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, proto_tree *ws_tree, guint8 opcode, guint payload_length, guint8 mask, const guint8* masking_key)
+#ifdef HAVE_ZLIB
+static gint8
+websocket_extract_wbits(const gchar *str)
{
- guint offset = 0;
- proto_item *ti_unmask, *ti;
- dissector_handle_t handle;
- proto_tree *pl_tree, *mask_tree = NULL;
- tvbuff_t *payload_tvb = NULL;
-
- /* Payload */
- ti = proto_tree_add_item(ws_tree, hf_ws_payload, tvb, offset, payload_length, ENC_NA);
- pl_tree = proto_item_add_subtree(ti, ett_ws_pl);
- if (mask) {
- payload_tvb = tvb_unmasked(tvb, offset, payload_length, masking_key);
- tvb_set_child_real_data_tvbuff(tvb, payload_tvb);
- add_new_data_source(pinfo, payload_tvb, payload_length > tvb_length(payload_tvb) ? "Unmasked Data (truncated)" : "Unmasked Data");
- ti = proto_tree_add_item(ws_tree, hf_ws_payload_unmask, payload_tvb, offset, payload_length, ENC_NA);
- mask_tree = proto_item_add_subtree(ti, ett_ws_mask);
+ guint8 wbits;
+ const gchar *end;
+
+ if (str && ws_strtou8(str, &end, &wbits) &&
+ (*end == '\0' || strchr(";\t ", *end))) {
+ if (wbits < 8) {
+ wbits = 8;
+ } else if (wbits > 15) {
+ wbits = 15;
+ }
} else {
- payload_tvb = tvb_new_subset(tvb, offset, payload_length, -1);
+ wbits = 15;
+ }
+ return -wbits;
+}
+
+static void *
+websocket_zalloc(void *opaque _U_, unsigned int items, unsigned int size)
+{
+ return wmem_alloc(wmem_file_scope(), items*size);
+}
+
+static void
+websocket_zfree(void *opaque _U_, void *addr)
+{
+ wmem_free(wmem_file_scope(), addr);
+}
+
+static z_streamp
+websocket_init_z_stream_context(gint8 wbits)
+{
+ z_streamp z_strm = wmem_new0(wmem_file_scope(), z_stream);
+
+ z_strm->zalloc = websocket_zalloc;
+ z_strm->zfree = websocket_zfree;
+
+ if (inflateInit2(z_strm, wbits) != Z_OK) {
+ inflateEnd(z_strm);
+ wmem_free(wmem_file_scope(), z_strm);
+ return NULL;
}
+ return z_strm;
+}
- handle = dissector_get_uint_handle(port_subdissector_table, pinfo->match_uint);
- if (handle != NULL) {
- call_dissector_only(handle, payload_tvb, pinfo, tree, NULL);
+/*
+ * Decompress the given buffer using the given zlib context. On success, the
+ * (possibly empty) buffer is stored as "proto data" and TRUE is returned.
+ * Otherwise FALSE is returned.
+ */
+static gboolean
+websocket_uncompress(tvbuff_t *tvb, packet_info *pinfo, z_streamp z_strm, tvbuff_t **uncompressed_tvb, guint32 key)
+{
+ /*
+ * Decompression a message: append "0x00 0x00 0xff 0xff" to the end of
+ * message, then apply DEFLATE to the result.
+ * https://tools.ietf.org/html/rfc7692#section-7.2.2
+ */
+ guint8 *decompr_payload = NULL;
+ guint decompr_len = 0;
+ guint compr_len, decompr_buf_len;
+ guint8 *compr_payload, *decompr_buf;
+ gint err;
+
+ compr_len = tvb_captured_length(tvb) + 4;
+ compr_payload = (guint8 *)wmem_alloc(wmem_packet_scope(), compr_len);
+ tvb_memcpy(tvb, compr_payload, 0, compr_len-4);
+ compr_payload[compr_len-4] = compr_payload[compr_len-3] = 0x00;
+ compr_payload[compr_len-2] = compr_payload[compr_len-1] = 0xff;
+ decompr_buf_len = 2*compr_len;
+ decompr_buf = (guint8 *)wmem_alloc(wmem_packet_scope(), decompr_buf_len);
+
+ z_strm->next_in = compr_payload;
+ z_strm->avail_in = compr_len;
+ /* Decompress all available data. */
+ do {
+ z_strm->next_out = decompr_buf;
+ z_strm->avail_out = decompr_buf_len;
+
+ err = inflate(z_strm, Z_SYNC_FLUSH);
+
+ if (err == Z_OK || err == Z_STREAM_END || err == Z_BUF_ERROR) {
+ guint avail_bytes = decompr_buf_len - z_strm->avail_out;
+ if (avail_bytes) {
+ decompr_payload = (guint8 *)wmem_realloc(wmem_file_scope(), decompr_payload,
+ decompr_len + avail_bytes);
+ memcpy(&decompr_payload[decompr_len], decompr_buf, avail_bytes);
+ decompr_len += avail_bytes;
+ }
+ }
+ } while (err == Z_OK);
+
+ if (err == Z_STREAM_END || err == Z_BUF_ERROR) {
+ /* Data was (partially) uncompressed. */
+ websocket_packet_t *pkt_info = wmem_new0(wmem_file_scope(), websocket_packet_t);
+ if (decompr_len > 0) {
+ pkt_info->decompr_payload = decompr_payload;
+ pkt_info->decompr_len = decompr_len;
+ *uncompressed_tvb = tvb_new_real_data(decompr_payload, decompr_len, decompr_len);
+ }
+ p_add_proto_data(wmem_file_scope(), pinfo, proto_websocket, key, pkt_info);
+ return TRUE;
} else {
- dissector_try_heuristic(heur_subdissector_list, payload_tvb, pinfo, tree, NULL);
+ /* decompression failed */
+ wmem_free(wmem_file_scope(), decompr_payload);
+ return FALSE;
}
+}
+#endif
- /* Extension Data */
- /* TODO: Add dissector of Extension (not extension available for the moment...) */
+static void
+dissect_websocket_control_frame(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, guint8 opcode)
+{
+ proto_item *ti;
+ proto_tree *subtree;
+ const guint offset = 0, length = tvb_reported_length(tvb);
- /* Application Data */
switch (opcode) {
+ case WS_CLOSE: /* Close */
+ ti = proto_tree_add_item(tree, hf_ws_payload_close, tvb, offset, length, ENC_NA);
+ subtree = proto_item_add_subtree(ti, ett_ws_control_close);
+ /* Close frame MAY contain a body. */
+ if (length >= 2) {
+ proto_tree_add_item(subtree, hf_ws_payload_close_status_code, tvb, offset, 2, ENC_BIG_ENDIAN);
+ if (length > 2)
+ proto_tree_add_item(subtree, hf_ws_payload_close_reason, tvb, offset+2, length-2, ENC_UTF_8|ENC_NA);
+ }
+ break;
- case WS_CONTINUE: /* Continue */
- proto_tree_add_item(pl_tree, hf_ws_payload_continue, tvb, offset, payload_length, ENC_NA);
- /* TODO: Add Fragmentation support... */
- break;
+ case WS_PING: /* Ping */
+ proto_tree_add_item(tree, hf_ws_payload_ping, tvb, offset, length, ENC_NA);
+ break;
- case WS_TEXT: /* Text */
- if (mask) {
+ case WS_PONG: /* Pong */
+ proto_tree_add_item(tree, hf_ws_payload_pong, tvb, offset, length, ENC_NA);
+ break;
+
+ default: /* Unknown */
+ ti = proto_tree_add_item(tree, hf_ws_payload_unknown, tvb, offset, length, ENC_NA);
+ expert_add_info_format(pinfo, ti, &ei_ws_payload_unknown, "Dissector for Websocket Opcode (%d)"
+ " code not implemented, Contact Wireshark developers"
+ " if you want this supported", opcode);
+ break;
+ }
+}
- proto_tree_add_item(pl_tree, hf_ws_payload_text_mask, tvb, offset, payload_length, ENC_NA);
- ti_unmask = proto_tree_add_item(mask_tree, hf_ws_payload_text_unmask, payload_tvb, offset, payload_length, ENC_UTF_8|ENC_NA);
- PROTO_ITEM_SET_GENERATED(ti_unmask);
- ti_unmask = proto_tree_add_item(mask_tree, hf_ws_payload_text, payload_tvb, offset, payload_length, ENC_UTF_8|ENC_NA);
- PROTO_ITEM_SET_HIDDEN(ti_unmask);
+static void
+dissect_websocket_data_frame(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, proto_tree *pl_tree, guint8 opcode, websocket_conv_t *websocket_conv, gboolean pmc _U_, gint raw_offset _U_)
+{
+ proto_item *ti;
+ dissector_handle_t handle = NULL;
+ heur_dtbl_entry_t *hdtbl_entry;
+
+ /* try to find a dissector which accepts the data. */
+ if (websocket_conv->subprotocol) {
+ handle = dissector_get_string_handle(protocol_subdissector_table, websocket_conv->subprotocol);
+ } else if (websocket_conv->server_port) {
+ handle = dissector_get_uint_handle(port_subdissector_table, websocket_conv->server_port);
+ }
+
+#ifdef HAVE_ZLIB
+ if (websocket_conv->permessage_deflate_ok && pmc) {
+ tvbuff_t *uncompressed = NULL;
+ gboolean uncompress_ok = FALSE;
+
+ if (!PINFO_FD_VISITED(pinfo)) {
+ z_streamp z_strm;
+ gint8 wbits;
+
+ if (pinfo->destport == websocket_conv->server_port) {
+ z_strm = websocket_conv->server_take_over_context;
+ wbits = websocket_conv->server_wbits;
+ } else {
+ z_strm = websocket_conv->client_take_over_context;
+ wbits = websocket_conv->client_wbits;
+ }
+
+ if (z_strm) {
+ uncompress_ok = websocket_uncompress(tvb, pinfo, z_strm, &uncompressed, raw_offset);
+ } else {
+ /* no context take over, initialize a new context */
+ z_strm = wmem_new0(wmem_packet_scope(), z_stream);
+ if (inflateInit2(z_strm, wbits) == Z_OK) {
+ uncompress_ok = websocket_uncompress(tvb, pinfo, z_strm, &uncompressed, raw_offset);
+ }
+ inflateEnd(z_strm);
+ }
} else {
+ websocket_packet_t *pkt_info =
+ (websocket_packet_t *)p_get_proto_data(wmem_file_scope(), pinfo, proto_websocket, raw_offset);
+ if (pkt_info) {
+ uncompress_ok = TRUE;
+ if (pkt_info->decompr_len > 0) {
+ uncompressed = tvb_new_real_data(pkt_info->decompr_payload, pkt_info->decompr_len, pkt_info->decompr_len);
+ }
+ }
+ }
+
+ if (!uncompress_ok) {
+ proto_tree_add_expert(tree, pinfo, &ei_ws_decompression_failed, tvb, 0, -1);
+ return;
+ }
+ if (uncompressed) {
+ add_new_data_source(pinfo, uncompressed, "Decompressed payload");
+ tvb = uncompressed;
+ }
+ }
+#endif
+
+ if (handle) {
+ call_dissector_only(handle, tvb, pinfo, tree, NULL);
+ return; /* handle found, assume dissector took care of it. */
+ } else if (dissector_try_heuristic(heur_subdissector_list, tvb, pinfo, tree, &hdtbl_entry, NULL)) {
+ return; /* heuristics dissector handled it. */
+ }
+
+ /* no dissector wanted it, try to print something appropriate. */
+ switch (opcode) {
+ case WS_TEXT: /* Text */
+ {
const gchar *saved_match_string = pinfo->match_string;
- void *save_private_data = pinfo->private_data;
pinfo->match_string = NULL;
- pinfo->private_data = NULL;
switch (pref_text_type) {
case WEBSOCKET_TEXT:
- call_dissector(text_lines_handle, payload_tvb, pinfo, pl_tree);
- break;
- case WEBSOCKET_JSON:
- call_dissector(json_handle, payload_tvb, pinfo, pl_tree);
- break;
- case WEBSOCKET_SIP:
- call_dissector(sip_handle, payload_tvb, pinfo, pl_tree);
- break;
case WEBSOCKET_NONE:
- /* falltrough */
default:
- proto_tree_add_item(pl_tree, hf_ws_payload_text, tvb, offset, payload_length, ENC_UTF_8|ENC_NA);
- break;
+ /* Assume that most text protocols are line-based. */
+ call_dissector(text_lines_handle, tvb, pinfo, tree);
+ break;
+ case WEBSOCKET_JSON:
+ call_dissector(json_handle, tvb, pinfo, tree);
+ break;
+ case WEBSOCKET_SIP:
+ call_dissector(sip_handle, tvb, pinfo, tree);
+ break;
}
pinfo->match_string = saved_match_string;
- pinfo->private_data = save_private_data;
}
- offset += payload_length;
break;
case WS_BINARY: /* Binary */
- if (mask) {
- proto_tree_add_item(pl_tree, hf_ws_payload_binary_mask, tvb, offset, payload_length, ENC_NA);
- ti_unmask = proto_tree_add_item(mask_tree, hf_ws_payload_binary_unmask, payload_tvb, offset, payload_length, ENC_NA);
- PROTO_ITEM_SET_GENERATED(ti_unmask);
- ti_unmask = proto_tree_add_item(mask_tree, hf_ws_payload_binary, payload_tvb, offset, payload_length, ENC_NA);
- PROTO_ITEM_SET_HIDDEN(ti_unmask);
- } else {
- proto_tree_add_item(pl_tree, hf_ws_payload_binary, tvb, offset, payload_length, ENC_NA);
- }
- offset += payload_length;
- break;
-
- case WS_CLOSE: /* Close */
- if (mask) {
- proto_tree_add_item(pl_tree, hf_ws_payload_close_mask, tvb, offset, payload_length, ENC_NA);
- ti_unmask = proto_tree_add_item(mask_tree, hf_ws_payload_close_unmask, payload_tvb, offset, payload_length, ENC_NA);
- PROTO_ITEM_SET_GENERATED(ti_unmask);
- ti_unmask = proto_tree_add_item(mask_tree, hf_ws_payload_close, payload_tvb, offset, payload_length, ENC_NA);
- PROTO_ITEM_SET_HIDDEN(ti_unmask);
- ti_unmask = proto_tree_add_item(mask_tree, hf_ws_payload_close_status_code, payload_tvb, offset, 2, ENC_BIG_ENDIAN);
- PROTO_ITEM_SET_GENERATED(ti_unmask);
-
- if (payload_length > 2) {
- ti_unmask = proto_tree_add_item(mask_tree, hf_ws_payload_close_reason, payload_tvb, offset+2, payload_length-2, ENC_ASCII|ENC_NA);
- PROTO_ITEM_SET_GENERATED(ti_unmask);
- }
- } else {
- proto_tree_add_item(pl_tree, hf_ws_payload_close, tvb, offset, payload_length, ENC_NA);
- proto_tree_add_item(pl_tree, hf_ws_payload_close_status_code, tvb, offset, 2, ENC_BIG_ENDIAN);
- if (payload_length > 2) {
- proto_tree_add_item(pl_tree, hf_ws_payload_close_reason, tvb, offset+2, payload_length-2, ENC_ASCII|ENC_NA);
- }
- }
- offset += payload_length;
- break;
-
- case WS_PING: /* Ping */
- if (mask) {
- proto_tree_add_item(pl_tree, hf_ws_payload_ping_mask, tvb, offset, payload_length, ENC_NA);
- ti_unmask = proto_tree_add_item(mask_tree, hf_ws_payload_ping_unmask, payload_tvb, offset, payload_length, ENC_NA);
- PROTO_ITEM_SET_GENERATED(ti_unmask);
- ti_unmask = proto_tree_add_item(mask_tree, hf_ws_payload_ping, payload_tvb, offset, payload_length, ENC_NA);
- PROTO_ITEM_SET_HIDDEN(ti_unmask);
- } else {
- proto_tree_add_item(pl_tree, hf_ws_payload_ping, tvb, offset, payload_length, ENC_NA);
- }
- offset += payload_length;
- break;
-
- case WS_PONG: /* Pong */
- if (mask) {
- proto_tree_add_item(pl_tree, hf_ws_payload_pong_mask, tvb, offset, payload_length, ENC_NA);
- ti_unmask = proto_tree_add_item(mask_tree, hf_ws_payload_pong_unmask, payload_tvb, offset, payload_length, ENC_NA);
- PROTO_ITEM_SET_GENERATED(ti_unmask);
- ti_unmask = proto_tree_add_item(mask_tree, hf_ws_payload_pong, payload_tvb, offset, payload_length, ENC_NA);
- PROTO_ITEM_SET_HIDDEN(ti_unmask);
- } else {
- proto_tree_add_item(pl_tree, hf_ws_payload_pong, tvb, offset, payload_length, ENC_NA);
- }
- offset += payload_length;
- break;
+ call_data_dissector(tvb, pinfo, tree);
+ break;
default: /* Unknown */
- ti = proto_tree_add_item(pl_tree, hf_ws_payload_unknown, tvb, offset, payload_length, ENC_NA);
+ ti = proto_tree_add_item(pl_tree, hf_ws_payload_unknown, tvb, 0, -1, ENC_NA);
expert_add_info_format(pinfo, ti, &ei_ws_payload_unknown, "Dissector for Websocket Opcode (%d)"
" code not implemented, Contact Wireshark developers"
" if you want this supported", opcode);
- break;
+ break;
+ }
+}
+
+static void
+websocket_parse_extensions(websocket_conv_t *websocket_conv, const char *str)
+{
+ /*
+ * Grammar for the header:
+ *
+ * Sec-WebSocket-Extensions = extension-list
+ * extension-list = 1#extension
+ * extension = extension-token *( ";" extension-param )
+ * extension-token = registered-token
+ * registered-token = token
+ * extension-param = token [ "=" (token | quoted-string) ]
+ */
+
+ /*
+ * RFC 7692 permessage-deflate parsing.
+ */
+
+ websocket_conv->permessage_deflate = !!strstr(str, "permessage-deflate");
+#ifdef HAVE_ZLIB
+ websocket_conv->permessage_deflate_ok = pref_decompress &&
+ websocket_conv->permessage_deflate;
+ if (websocket_conv->permessage_deflate_ok) {
+ websocket_conv->server_wbits =
+ websocket_extract_wbits(strstr(str, "server_max_window_bits="));
+ if (!strstr(str, "server_no_context_takeover")) {
+ websocket_conv->server_take_over_context =
+ websocket_init_z_stream_context(websocket_conv->server_wbits);
+ }
+ websocket_conv->client_wbits =
+ websocket_extract_wbits(strstr(str, "client_max_window_bits="));
+ if (!strstr(str, "client_no_context_takeover")) {
+ websocket_conv->client_take_over_context =
+ websocket_init_z_stream_context(websocket_conv->client_wbits);
+ }
+ }
+#endif
+}
+
+static void
+dissect_websocket_payload(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, proto_tree *ws_tree, guint8 opcode, websocket_conv_t *websocket_conv, gboolean pmc, gint raw_offset)
+{
+ const guint offset = 0, length = tvb_reported_length(tvb);
+ proto_item *ti;
+ proto_tree *pl_tree;
+ tvbuff_t *tvb_appdata;
+
+ /* Payload */
+ ti = proto_tree_add_item(ws_tree, hf_ws_payload, tvb, offset, length, ENC_NA);
+ pl_tree = proto_item_add_subtree(ti, ett_ws_pl);
+
+ /* Extension Data */
+ /* TODO: Add dissector of Extension (not extension available for the moment...) */
+
+
+ /* Application Data */
+ if (opcode == WS_CONTINUE) {
+ proto_tree_add_item(tree, hf_ws_payload_continue, tvb, offset, length, ENC_NA);
+ /* TODO: Add Fragmentation support (needs FIN bit)
+ * https://tools.ietf.org/html/rfc6455#section-5.4 */
+ return;
+ }
+ /* Right now this is exactly the same, this may change when exts. are added.
+ tvb_appdata = tvb_new_subset_length_caplen(tvb, offset, length, length);
+ */
+ tvb_appdata = tvb;
+
+ if (opcode & 8) { /* Control frames have MSB set. */
+ dissect_websocket_control_frame(tvb_appdata, pinfo, pl_tree, opcode);
+ } else {
+ dissect_websocket_data_frame(tvb_appdata, pinfo, tree, pl_tree, opcode, websocket_conv, pmc, raw_offset);
}
- return offset;
}
static int
-dissect_websocket(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_)
+dissect_websocket_frame(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_)
{
proto_item *ti, *ti_len;
- guint8 fin, opcode, mask;
- guint length, short_length, payload_length, recurse_length;
- guint payload_offset, mask_offset, recurse_offset;
- proto_tree *ws_tree = NULL;
+ guint8 fin, opcode;
+ gboolean mask;
+ guint short_length, payload_length;
+ guint payload_offset, mask_offset;
+ proto_tree *ws_tree;
const guint8 *masking_key = NULL;
tvbuff_t *tvb_payload;
+ conversation_t *conv;
+ websocket_conv_t *websocket_conv;
+ gboolean pmc = FALSE;
- length = tvb_length(tvb);
- if (length < 2) {
- pinfo->desegment_len = 2;
- return 0;
+ /*
+ * If this is a new Websocket session, try to parse HTTP Sec-Websocket-*
+ * headers once.
+ */
+ conv = find_or_create_conversation(pinfo);
+ websocket_conv = (websocket_conv_t *)conversation_get_proto_data(conv, proto_websocket);
+ if (!websocket_conv) {
+ websocket_conv = wmem_new0(wmem_file_scope(), websocket_conv_t);
+
+ http_conv_t *http_conv = (http_conv_t *)conversation_get_proto_data(conv, proto_http);
+ if (http_conv) {
+ websocket_conv->subprotocol = http_conv->websocket_protocol;
+ websocket_conv->server_port = http_conv->server_port;
+ if ( http_conv->websocket_extensions) {
+ websocket_parse_extensions(websocket_conv, http_conv->websocket_extensions);
+ }
+ }
+
+ conversation_add_proto_data(conv, proto_websocket, websocket_conv);
}
short_length = tvb_get_guint8(tvb, 1) & MASK_WS_PAYLOAD_LEN;
+ mask_offset = 2;
if (short_length == 126) {
- if (length < 2+2) {
- pinfo->desegment_len = 2+2;
- return 0;
- }
payload_length = tvb_get_ntohs(tvb, 2);
- mask_offset = 2+2;
- }
- else if (short_length == 127) {
- if (length < 2+8) {
- pinfo->desegment_len = 2+8;
- return 0;
- }
+ mask_offset += 2;
+ } else if (short_length == 127) {
/* warning C4244: '=' : conversion from 'guint64' to 'guint ', possible loss of data */
payload_length = (guint)tvb_get_ntoh64(tvb, 2);
- mask_offset = 2+8;
- }
- else{
+ mask_offset += 8;
+ } else {
payload_length = short_length;
- mask_offset = 2;
}
/* Mask */
- mask = (tvb_get_guint8(tvb, 1) & MASK_WS_MASK) >> 4;
+ mask = (tvb_get_guint8(tvb, 1) & MASK_WS_MASK) != 0;
payload_offset = mask_offset + (mask ? 4 : 0);
- if (payload_offset + payload_length < payload_length) {
- /* Integer overflow, which means the packet contains a ridiculous
- * payload length. Just take what we've got available.
- * See bug https://bugs.wireshark.org/bugzilla/show_bug.cgi?id=8448 */
- payload_length = tvb_reported_length_remaining(tvb, payload_offset);
- }
-
- if (length < payload_offset + payload_length) {
- /* XXXX Warning desegment_len is 32 bits */
- pinfo->desegment_len = payload_offset + payload_length - length;
- return 0;
- }
-
- /* We've got the entire message! */
-
col_set_str(pinfo->cinfo, COL_PROTOCOL, "WebSocket");
col_set_str(pinfo->cinfo, COL_INFO, "WebSocket");
- if (tree) {
- ti = proto_tree_add_item(tree, proto_websocket, tvb, 0, payload_offset, ENC_NA);
- ws_tree = proto_item_add_subtree(ti, ett_ws);
- }
+ ti = proto_tree_add_item(tree, proto_websocket, tvb, 0, payload_offset, ENC_NA);
+ ws_tree = proto_item_add_subtree(ti, ett_ws);
/* Flags */
proto_tree_add_item(ws_tree, hf_ws_fin, tvb, 0, 1, ENC_NA);
fin = (tvb_get_guint8(tvb, 0) & MASK_WS_FIN) >> 4;
- proto_tree_add_item(ws_tree, hf_ws_reserved, tvb, 0, 1, ENC_NA);
+ proto_tree_add_item(ws_tree, hf_ws_reserved, tvb, 0, 1, ENC_BIG_ENDIAN);
+ if (websocket_conv->permessage_deflate) {
+ /* RSV1 is Per-Message Compressed bit (RFC 7692). */
+ pmc = !!(tvb_get_guint8(tvb, 0) & MASK_WS_RSV1);
+ proto_tree_add_item(ws_tree, hf_ws_pmc, tvb, 0, 1, ENC_BIG_ENDIAN);
+ }
/* Opcode */
- proto_tree_add_item(ws_tree, hf_ws_opcode, tvb, 0, 1, ENC_NA);
+ proto_tree_add_item(ws_tree, hf_ws_opcode, tvb, 0, 1, ENC_BIG_ENDIAN);
opcode = tvb_get_guint8(tvb, 0) & MASK_WS_OPCODE;
col_append_fstr(pinfo->cinfo, COL_INFO, " %s", val_to_str_const(opcode, ws_opcode_vals, "Unknown Opcode"));
col_append_str(pinfo->cinfo, COL_INFO, fin ? " [FIN]" : " ");
col_append_str(pinfo->cinfo, COL_INFO, mask ? " [MASKED]" : " ");
/* (Extended) Payload Length */
- ti_len = proto_tree_add_item(ws_tree, hf_ws_payload_length, tvb, 1, 1, ENC_NA);
+ ti_len = proto_tree_add_item(ws_tree, hf_ws_payload_length, tvb, 1, 1, ENC_BIG_ENDIAN);
if (short_length == 126) {
proto_item_append_text(ti_len, " Extended Payload Length (16 bits)");
proto_tree_add_item(ws_tree, hf_ws_payload_length_ext_16, tvb, 2, 2, ENC_BIG_ENDIAN);
masking_key = tvb_get_ptr(tvb, mask_offset, 4);
}
- tvb_payload = tvb_new_subset_remaining(tvb, payload_offset);
- dissect_websocket_payload(tvb_payload, pinfo, tree, ws_tree, opcode, payload_length, mask, masking_key);
+ if (payload_length > 0) {
+ /* Always unmask payload data before analysing it. */
+ if (mask) {
+ proto_tree_add_item(ws_tree, hf_ws_masked_payload, tvb, payload_offset, payload_length, ENC_NA);
+ tvb_payload = tvb_unmasked(tvb, pinfo, payload_offset, payload_length, masking_key);
+ tvb_set_child_real_data_tvbuff(tvb, tvb_payload);
+ add_new_data_source(pinfo, tvb_payload, "Unmasked data");
+ } else {
+ tvb_payload = tvb_new_subset_length_caplen(tvb, payload_offset, payload_length, payload_length);
+ }
+ dissect_websocket_payload(tvb_payload, pinfo, tree, ws_tree, opcode, websocket_conv, pmc, tvb_raw_offset(tvb));
+ }
+
+ return tvb_captured_length(tvb);
+}
+
+static guint
+get_websocket_frame_length(packet_info *pinfo _U_, tvbuff_t *tvb, int offset, void *data _U_)
+{
+ guint frame_length, payload_length;
+ gboolean mask;
+
+ frame_length = 2; /* flags, opcode and Payload length */
+ mask = tvb_get_guint8(tvb, offset + 1) & MASK_WS_MASK;
+
+ payload_length = tvb_get_guint8(tvb, offset + 1) & MASK_WS_PAYLOAD_LEN;
+ offset += 2; /* Skip flags, opcode and Payload length */
- /* Call this function recursively, to see if we have enough data to parse another websocket message */
+ /* Check for Extended Payload Length. */
+ if (payload_length == 126) {
+ if (tvb_reported_length_remaining(tvb, offset) < 2)
+ return 0; /* Need more data. */
- recurse_offset = payload_offset + payload_length;
- if (length > recurse_offset) {
- recurse_length = dissect_websocket(tvb_new_subset_remaining(tvb, payload_offset+payload_length), pinfo, tree, data);
- if (pinfo->desegment_len) pinfo->desegment_offset += recurse_offset;
- return recurse_offset + recurse_length;
+ payload_length = tvb_get_ntohs(tvb, offset);
+ frame_length += 2; /* Extended payload length */
+ } else if (payload_length == 127) {
+ if (tvb_reported_length_remaining(tvb, offset) < 8)
+ return 0; /* Need more data. */
+
+ payload_length = (guint)tvb_get_ntoh64(tvb, offset);
+ frame_length += 8; /* Extended payload length */
}
- return recurse_offset;
+
+ if (mask)
+ frame_length += 4; /* Masking-key */
+ frame_length += payload_length; /* Payload data */
+ return frame_length;
+}
+
+static int
+dissect_websocket(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data)
+{
+ /* Need at least two bytes for flags, opcode and Payload length. */
+ tcp_dissect_pdus(tvb, pinfo, tree, TRUE, 2,
+ get_websocket_frame_length, dissect_websocket_frame, data);
+ return tvb_captured_length(tvb);
}
FT_UINT8, BASE_HEX, NULL, MASK_WS_RSV,
"Must be zero", HFILL }
},
+ { &hf_ws_pmc,
+ { "Per-Message Compressed", "websocket.pmc",
+ FT_BOOLEAN, 8, NULL, MASK_WS_RSV1,
+ "Whether a message is compressed or not", HFILL }
+ },
{ &hf_ws_opcode,
{ "Opcode", "websocket.opcode",
FT_UINT8, BASE_DEC, VALS(ws_opcode_vals), MASK_WS_OPCODE,
{ &hf_ws_payload,
{ "Payload", "websocket.payload",
FT_NONE, BASE_NONE, NULL, 0x0,
- NULL, HFILL }
+ "Payload (after unmasking)", HFILL }
},
- { &hf_ws_payload_unmask,
- { "Unmask Payload", "websocket.payload.unmask",
+ { &hf_ws_masked_payload,
+ { "Masked payload", "websocket.masked_payload",
FT_NONE, BASE_NONE, NULL, 0x0,
NULL, HFILL }
},
FT_BYTES, BASE_NONE, NULL, 0x0,
NULL, HFILL }
},
- { &hf_ws_payload_text,
- { "Text", "websocket.payload.text",
- FT_STRING, BASE_NONE, NULL, 0x0,
- NULL, HFILL }
- },
- { &hf_ws_payload_text_mask,
- { "Text", "websocket.payload.text_mask",
- FT_BYTES, BASE_NONE, NULL, 0x0,
- NULL, HFILL }
- },
- { &hf_ws_payload_text_unmask,
- { "Text unmask", "websocket.payload.text_unmask",
- FT_STRING, BASE_NONE, NULL, 0x0,
- NULL, HFILL }
- },
- { &hf_ws_payload_binary,
- { "Binary", "websocket.payload.binary",
- FT_BYTES, BASE_NONE, NULL, 0x0,
- NULL, HFILL }
- },
- { &hf_ws_payload_binary_mask,
- { "Binary", "websocket.payload.binary_mask",
- FT_BYTES, BASE_NONE, NULL, 0x0,
- NULL, HFILL }
- },
- { &hf_ws_payload_binary_unmask,
- { "Binary", "websocket.payload.binary_unmask",
- FT_BYTES, BASE_NONE, NULL, 0x0,
- NULL, HFILL }
- },
{ &hf_ws_payload_close,
{ "Close", "websocket.payload.close",
- FT_BYTES, BASE_NONE, NULL, 0x0,
- NULL, HFILL }
- },
- { &hf_ws_payload_close_mask,
- { "Close", "websocket.payload.close_mask",
- FT_BYTES, BASE_NONE, NULL, 0x0,
- NULL, HFILL }
- },
- { &hf_ws_payload_close_unmask,
- { "Unmask Close", "websocket.payload.close_unmask",
- FT_BYTES, BASE_NONE, NULL, 0x0,
+ FT_NONE, BASE_NONE, NULL, 0x0,
NULL, HFILL }
},
{ &hf_ws_payload_close_status_code,
- { "Close", "websocket.payload.close.status_code",
+ { "Status code", "websocket.payload.close.status_code",
FT_UINT16, BASE_DEC, VALS(ws_close_status_code_vals), 0x0,
NULL, HFILL }
},
FT_BYTES, BASE_NONE, NULL, 0x0,
NULL, HFILL }
},
- { &hf_ws_payload_ping_mask,
- { "Ping", "websocket.payload.ping_mask",
- FT_BYTES, BASE_NONE, NULL, 0x0,
- NULL, HFILL }
- },
- { &hf_ws_payload_ping_unmask,
- { "Ping", "websocket.payload.ping_unmask",
- FT_BYTES, BASE_NONE, NULL, 0x0,
- NULL, HFILL }
- },
{ &hf_ws_payload_pong,
{ "Pong", "websocket.payload.pong",
FT_BYTES, BASE_NONE, NULL, 0x0,
NULL, HFILL }
},
- { &hf_ws_payload_pong_mask,
- { "Pong", "websocket.payload.pong_mask",
- FT_BYTES, BASE_NONE, NULL, 0x0,
- NULL, HFILL }
- },
- { &hf_ws_payload_pong_unmask,
- { "Pong", "websocket.payload.pong_unmask",
- FT_BYTES, BASE_NONE, NULL, 0x0,
- NULL, HFILL }
- },
{ &hf_ws_payload_unknown,
{ "Unknown", "websocket.payload.unknown",
FT_BYTES, BASE_NONE, NULL, 0x0,
static gint *ett[] = {
&ett_ws,
&ett_ws_pl,
- &ett_ws_mask
+ &ett_ws_mask,
+ &ett_ws_control_close,
};
static ei_register_info ei[] = {
- { &ei_ws_payload_unknown, { "websocket.payload.unknown.expert", PI_UNDECODED, PI_NOTE, "Dissector for Websocket Opcode", EXPFILL }},
+ { &ei_ws_payload_unknown, { "websocket.payload.unknown.expert", PI_UNDECODED, PI_NOTE, "Dissector for Websocket Opcode", EXPFILL }},
+ { &ei_ws_decompression_failed, { "websocket.decompression.failed.expert", PI_PROTOCOL, PI_WARN, "Decompression failed", EXPFILL }},
};
static const enum_val_t text_types[] = {
* this table using the standard heur_dissector_add()
* function.
*/
- register_heur_dissector_list("ws", &heur_subdissector_list);
+ heur_subdissector_list = register_heur_dissector_list("ws", proto_websocket);
port_subdissector_table = register_dissector_table("ws.port",
- "TCP port for protocols using WebSocket", FT_UINT16, BASE_DEC);
+ "TCP port for protocols using WebSocket", proto_websocket, FT_UINT16, BASE_DEC);
+
+ protocol_subdissector_table = register_dissector_table("ws.protocol",
+ "Negotiated WebSocket protocol", proto_websocket, FT_STRING, BASE_NONE);
proto_register_field_array(proto_websocket, hf, array_length(hf));
proto_register_subtree_array(ett, array_length(ett));
expert_websocket = expert_register_protocol(proto_websocket);
expert_register_field_array(expert_websocket, ei, array_length(ei));
- new_register_dissector("websocket", dissect_websocket, proto_websocket);
+ websocket_handle = register_dissector("websocket", dissect_websocket, proto_websocket);
websocket_module = prefs_register_protocol(proto_websocket, proto_reg_handoff_websocket);
"Dissect websocket text as",
"Select dissector for websocket text",
&pref_text_type, text_types, WEBSOCKET_NONE);
-
-
+ prefs_register_bool_preference(websocket_module, "decompress",
+ "Try to decompress permessage-deflate payload", NULL, &pref_decompress);
}
void
proto_reg_handoff_websocket(void)
{
- text_lines_handle = find_dissector("data-text-lines");
- json_handle = find_dissector("json");
- sip_handle = find_dissector("sip");
+ dissector_add_string("http.upgrade", "websocket", websocket_handle);
+
+ text_lines_handle = find_dissector_add_dependency("data-text-lines", proto_websocket);
+ json_handle = find_dissector_add_dependency("json", proto_websocket);
+ sip_handle = find_dissector_add_dependency("sip", proto_websocket);
+
+ proto_http = proto_get_id_by_filter_name("http");
}
/*
- * Editor modelines - http://www.wireshark.org/tools/modelines.html
+ * Editor modelines - https://www.wireshark.org/tools/modelines.html
*
* Local variables:
* c-basic-offset: 2
git.samba.org / metze / wireshark / wip.git / blobdiff