2 * Routines for the Session Initiation Protocol (SIP) dissection.
5 * TODO: Pay attention to Content-Type: It might not always be SDP.
6 * Add hf_* fields for filtering support.
7 * Add sip msg body dissection based on Content-Type for:
8 * SDP, MIME, and other types
9 * Align SIP methods with recent Internet Drafts or RFC
10 * (SIP INFO, rfc2976 - done)
11 * (SIP SUBSCRIBE-NOTIFY - done)
15 * Copyright 2000, Heikki Vatiainen <hessu@cs.tut.fi>
16 * Copyright 2001, Jean-Francois Mule <jfm@clarent.com>
18 * $Id: packet-sip.c,v 1.17 2001/10/26 18:28:16 gram Exp $
20 * Ethereal - Network traffic analyzer
21 * By Gerald Combs <gerald@ethereal.com>
22 * Copyright 1998 Gerald Combs
24 * Copied from packet-cops.c
26 * This program is free software; you can redistribute it and/or
27 * modify it under the terms of the GNU General Public License
28 * as published by the Free Software Foundation; either version 2
29 * of the License, or (at your option) any later version.
31 * This program is distributed in the hope that it will be useful,
32 * but WITHOUT ANY WARRANTY; without even the implied warranty of
33 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
34 * GNU General Public License for more details.
36 * You should have received a copy of the GNU General Public License
37 * along with this program; if not, write to the Free Software
38 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
52 #define TCP_PORT_SIP 5060
53 #define UDP_PORT_SIP 5060
55 /* Initialize the protocol and registered fields */
56 static gint proto_sip = -1;
57 static gint hf_msg_hdr = -1;
59 /* Initialize the subtree pointers */
60 static gint ett_sip = -1;
61 static gint ett_sip_hdr = -1;
63 static const char *sip_methods[] = {
64 "<Invalid method>", /* Pad so that the real methods start at index 1 */
77 static gboolean sip_is_request(tvbuff_t *tvb, guint32 offset);
78 static gint sip_get_msg_offset(tvbuff_t *tvb, guint32 offset);
80 static dissector_handle_t sdp_handle;
82 #define SIP2_HDR "SIP/2.0 "
83 #define SIP2_HDR_LEN (strlen (SIP2_HDR))
85 /* Code to actually dissect the packets */
86 static void dissect_sip(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
89 gint eol, next_offset, msg_offset;
94 * Note that "tvb_strneql()" doesn't throw exceptions, so
95 * "sip_is_request()" won't throw an exception.
97 * Note that "tvb_find_line_end()" will return a value that
98 * is not longer than what's in the buffer, so the
99 * "tvb_get_ptr()" call s below won't throw exceptions.
102 eol = tvb_find_line_end(tvb, 0, -1, &next_offset);
103 is_request = sip_is_request(tvb, 0);
104 /* XXX - Is this case-sensitive? RFC 2543 didn't explicitly say. */
105 if (tvb_strneql(tvb, 0, SIP2_HDR, SIP2_HDR_LEN) != 0 && ! is_request)
108 if (check_col(pinfo->fd, COL_PROTOCOL))
109 col_set_str(pinfo->fd, COL_PROTOCOL, "SIP");
112 if (check_col(pinfo->fd, COL_INFO))
113 col_add_fstr(pinfo->fd, COL_INFO, "%s: %s",
114 is_request ? "Request" : "Status",
116 tvb_format_text(tvb, 0, eol - SIP2_HDR_LEN) :
117 tvb_format_text(tvb, SIP2_HDR_LEN, eol - SIP2_HDR_LEN));
119 msg_offset = sip_get_msg_offset(tvb, offset);
120 if (msg_offset < 0) goto bad;
124 proto_tree *sip_tree, *hdr_tree;
126 ti = proto_tree_add_item(tree, proto_sip, tvb, 0, tvb_length(tvb), FALSE);
127 sip_tree = proto_item_add_subtree(ti, ett_sip);
129 proto_tree_add_text(sip_tree, tvb, 0, next_offset, "%s-Line: %s",
130 is_request ? "Request" : "Status",
131 tvb_format_text(tvb, 0, eol));
133 offset = next_offset;
134 th = proto_tree_add_item(sip_tree, hf_msg_hdr, tvb, offset, msg_offset - offset, FALSE);
135 hdr_tree = proto_item_add_subtree(th, ett_sip_hdr);
137 /* - 2 since we have a CRLF separating the message-body */
138 while (msg_offset - 2 > (int) offset) {
139 eol = tvb_find_line_end(tvb, offset, -1, &next_offset);
140 proto_tree_add_text(hdr_tree, tvb, offset, next_offset - offset, "%s",
141 tvb_format_text(tvb, offset, eol));
142 offset = next_offset;
144 offset += 2; /* Skip the CRLF mentioned above */
147 if (tvb_length_remaining(tvb, msg_offset) > 0) {
148 next_tvb = tvb_new_subset(tvb, offset, -1, -1);
149 call_dissector(sdp_handle, next_tvb, pinfo, tree);
155 next_tvb = tvb_new_subset(tvb, offset, -1, -1);
156 dissect_data(next_tvb, 0, pinfo, tree);
161 /* Returns the offset to the start of the optional message-body, or
164 static gint sip_get_msg_offset(tvbuff_t *tvb, guint32 offset)
168 while ((eol = tvb_find_guint8(tvb, offset, tvb_length_remaining(tvb, offset), '\r')) > 0) {
169 if (tvb_get_guint8(tvb, eol + 1) == '\n' &&
170 tvb_get_guint8(tvb, eol + 2) == '\r' &&
171 tvb_get_guint8(tvb, eol + 3) == '\n')
179 static gboolean sip_is_request(tvbuff_t *tvb, guint32 offset)
183 for (i = 1; i < array_length(sip_methods); i++) {
184 if (tvb_strneql(tvb, offset, sip_methods[i], strlen(sip_methods[i])) == 0)
191 /* Register the protocol with Ethereal */
192 void proto_register_sip(void)
195 /* Setup list of header fields */
196 static hf_register_info hf[] = {
199 { "Message Header", "sip.msg_hdr",
201 "Message Header in SIP message", HFILL }
205 /* Setup protocol subtree array */
206 static gint *ett[] = {
211 /* Register the protocol name and description */
212 proto_sip = proto_register_protocol("Session Initiation Protocol",
215 /* Required function calls to register the header fields and subtrees used */
216 proto_register_field_array(proto_sip, hf, array_length(hf));
217 proto_register_subtree_array(ett, array_length(ett));
221 proto_reg_handoff_sip(void)
223 dissector_add("tcp.port", TCP_PORT_SIP, dissect_sip, proto_sip);
224 dissector_add("udp.port", UDP_PORT_SIP, dissect_sip, proto_sip);
227 * Get a handle for the SDP dissector.
229 sdp_handle = find_dissector("sdp");