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.
8 * Copyright 2000, Heikki Vatiainen <hessu@cs.tut.fi>
10 * $Id: packet-sip.c,v 1.13 2001/01/30 02:38:33 gerald Exp $
12 * Ethereal - Network traffic analyzer
13 * By Gerald Combs <gerald@zing.org>
14 * Copyright 1998 Gerald Combs
16 * Copied from packet-cops.c
18 * This program is free software; you can redistribute it and/or
19 * modify it under the terms of the GNU General Public License
20 * as published by the Free Software Foundation; either version 2
21 * of the License, or (at your option) any later version.
23 * This program is distributed in the hope that it will be useful,
24 * but WITHOUT ANY WARRANTY; without even the implied warranty of
25 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
26 * GNU General Public License for more details.
28 * You should have received a copy of the GNU General Public License
29 * along with this program; if not, write to the Free Software
30 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
44 #define TCP_PORT_SIP 5060
45 #define UDP_PORT_SIP 5060
47 /* Initialize the protocol and registered fields */
48 static gint proto_sip = -1;
49 static gint hf_msg_hdr = -1;
51 /* Initialize the subtree pointers */
52 static gint ett_sip = -1;
53 static gint ett_sip_hdr = -1;
55 static const char *sip_methods[] = {
56 "<Invalid method>", /* Pad so that the real methods start at index 1 */
65 static int sip_is_request(tvbuff_t *tvb, guint32 offset);
66 static gint sip_get_msg_offset(tvbuff_t *tvb, guint32 offset);
68 static dissector_handle_t sdp_handle;
70 #define SIP2_HDR "SIP/2.0 "
71 #define SIP2_HDR_LEN (strlen (SIP2_HDR))
73 /* Code to actually dissect the packets */
74 static void dissect_sip(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
77 gint eol, next_offset, msg_offset;
82 * Note that "tvb_strneql()" doesn't throw exceptions, so
83 * "sip_is_request()" won't throw an exception.
85 * Note that "tvb_find_line_end()" will return a value that
86 * is not longer than what's in the buffer, so the
87 * "tvb_get_ptr()" call s below won't throw exceptions.
90 eol = tvb_find_line_end(tvb, 0, -1, &next_offset);
91 is_request = sip_is_request(tvb, 0);
92 /* XXX - Is this case-sensitive? RFC 2543 didn't explicitly say. */
93 if (tvb_strneql(tvb, 0, SIP2_HDR, SIP2_HDR_LEN) != 0 && ! is_request)
96 if (check_col(pinfo->fd, COL_PROTOCOL))
97 col_set_str(pinfo->fd, COL_PROTOCOL, "SIP");
100 if (check_col(pinfo->fd, COL_INFO))
101 col_add_fstr(pinfo->fd, COL_INFO, "%s: %s",
102 is_request ? "Request" : "Status",
104 tvb_format_text(tvb, 0, eol - SIP2_HDR_LEN) :
105 tvb_format_text(tvb, SIP2_HDR_LEN, eol - SIP2_HDR_LEN));
107 msg_offset = sip_get_msg_offset(tvb, offset);
108 if (msg_offset < 0) goto bad;
112 proto_tree *sip_tree, *hdr_tree;
114 ti = proto_tree_add_item(tree, proto_sip, tvb, 0, tvb_length(tvb), FALSE);
115 sip_tree = proto_item_add_subtree(ti, ett_sip);
117 proto_tree_add_text(sip_tree, tvb, 0, next_offset, "%s-Line: %s",
118 is_request ? "Request" : "Status",
119 tvb_format_text(tvb, 0, eol));
121 offset = next_offset;
122 th = proto_tree_add_item(sip_tree, hf_msg_hdr, tvb, offset, msg_offset - offset, FALSE);
123 hdr_tree = proto_item_add_subtree(th, ett_sip_hdr);
125 /* - 2 since we have a CRLF separating the message-body */
126 while (msg_offset - 2 > offset) {
127 eol = tvb_find_line_end(tvb, offset, -1, &next_offset);
128 proto_tree_add_text(hdr_tree, tvb, offset, next_offset - offset, "%s",
129 tvb_format_text(tvb, offset, eol));
130 offset = next_offset;
132 offset += 2; /* Skip the CRLF mentioned above */
135 if (tvb_length_remaining(tvb, msg_offset) > 0) {
136 next_tvb = tvb_new_subset(tvb, offset, -1, -1);
137 call_dissector(sdp_handle, next_tvb, pinfo, tree);
143 next_tvb = tvb_new_subset(tvb, offset, -1, -1);
144 dissect_data(next_tvb, 0, pinfo, tree);
149 /* Returns the offset to the start of the optional message-body, or
152 static gint sip_get_msg_offset(tvbuff_t *tvb, guint32 offset)
156 while ((eol = tvb_find_guint8(tvb, offset, tvb_length_remaining(tvb, offset), '\r')) > 0) {
157 if (tvb_get_guint8(tvb, eol + 1) == '\n' &&
158 tvb_get_guint8(tvb, eol + 2) == '\r' &&
159 tvb_get_guint8(tvb, eol + 3) == '\n')
167 static int sip_is_request(tvbuff_t *tvb, guint32 offset)
171 for (i = 1; i < array_length(sip_methods); i++) {
172 if (tvb_strneql(tvb, offset, sip_methods[i], strlen(sip_methods[i])) == 0)
179 /* Register the protocol with Ethereal */
180 void proto_register_sip(void)
183 /* Setup list of header fields */
184 static hf_register_info hf[] = {
187 { "Message Header", "sip.msg_hdr",
189 "Message Header in SIP message" }
193 /* Setup protocol subtree array */
194 static gint *ett[] = {
199 /* Register the protocol name and description */
200 proto_sip = proto_register_protocol("Session Initiation Protocol",
203 /* Required function calls to register the header fields and subtrees used */
204 proto_register_field_array(proto_sip, hf, array_length(hf));
205 proto_register_subtree_array(ett, array_length(ett));
209 proto_reg_handoff_sip(void)
211 dissector_add("tcp.port", TCP_PORT_SIP, dissect_sip, proto_sip);
212 dissector_add("udp.port", UDP_PORT_SIP, dissect_sip, proto_sip);
215 * Get a handle for the SDP dissector.
217 sdp_handle = find_dissector("sdp");