2 * Routines for sap packet dissection
5 * Heikki Vatiainen <hessu@cs.tut.fi>
7 * $Id: packet-sap.c,v 1.31 2002/12/02 23:43:29 guy Exp $
9 * Ethereal - Network traffic analyzer
10 * By Gerald Combs <gerald@ethereal.com>
11 * Copyright 1998 Gerald Combs
13 * Copied from packet-tftp.c
15 * This program is free software; you can redistribute it and/or
16 * modify it under the terms of the GNU General Public License
17 * as published by the Free Software Foundation; either version 2
18 * of the License, or (at your option) any later version.
20 * This program is distributed in the hope that it will be useful,
21 * but WITHOUT ANY WARRANTY; without even the implied warranty of
22 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
23 * GNU General Public License for more details.
25 * You should have received a copy of the GNU General Public License
26 * along with this program; if not, write to the Free Software
27 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
36 #include <epan/packet.h>
37 #include "packet-ipv6.h"
39 #define UDP_PORT_SAP 9875
41 #define MCAST_SAP_VERSION_MASK 0xE0 /* 3 bits for SAP version*/
42 #define MCAST_SAP_VERSION_SHIFT 5 /* Right shift 5 bits to get the version */
43 #define MCAST_SAP_VER0 0 /* Version 0 */
44 #define MCAST_SAP_VER1PLUS 1 /* Version 1 or later */
45 static const value_string mcast_sap_ver[] = {
46 { MCAST_SAP_VER0, "SAPv0"},
47 { MCAST_SAP_VER1PLUS, "SAPv1 or later"},
50 static const true_false_string mcast_sap_address_type = {
55 static const true_false_string mcast_sap_message_type = {
60 static const true_false_string mcast_sap_crypt_type = {
62 "Payload not encrypted "
65 static const true_false_string mcast_sap_comp_type = {
67 "Payload not compressed"
70 static const value_string mcast_sap_auth_ver[] = {
71 { 1, "SAP authentication header v1"},
74 static const true_false_string mcast_sap_auth_pad = {
75 "Authentication subheader padded to 32 bits",
76 "No padding required for the authentication subheader"
79 #define MCAST_SAP_AUTH_TYPE_MASK 0x0F /* 4 bits for the type of the authentication header */
80 #define MCAST_SAP_AUTH_TYPE_PGP 0
81 #define MCAST_SAP_AUTH_TYPE_CMS 1
82 static const value_string mcast_sap_auth_type[] = {
83 { MCAST_SAP_AUTH_TYPE_PGP, "PGP"},
84 { MCAST_SAP_AUTH_TYPE_CMS, "CMS"},
87 #define MCAST_SAP_BIT_A 0x10 /* Address type: 0 IPv4, 1 IPv6 */
88 #define MCAST_SAP_BIT_R 0x08 /* Reserved: Must be 0 */
89 #define MCAST_SAP_BIT_T 0x04 /* Message Type: 0 announcement, 1 deletion */
90 #define MCAST_SAP_BIT_E 0x02 /* Encryption Bit: 1 payload encrypted */
91 #define MCAST_SAP_BIT_C 0x01 /* Compressed Bit: 1 payload zlib compressed */
93 #define MCAST_SAP_AUTH_BIT_P 0x10 /* Padding required for the authentication header */
96 static int proto_sap = -1;
97 static int hf_sap_flags = -1;
98 static int hf_sap_flags_v = -1;
99 static int hf_sap_flags_a = -1;
100 static int hf_sap_flags_r = -1;
101 static int hf_sap_flags_t = -1;
102 static int hf_sap_flags_e = -1;
103 static int hf_sap_flags_c = -1;
104 static int hf_auth_data = -1;
105 static int hf_auth_flags = -1;
106 static int hf_auth_flags_v = -1;
107 static int hf_auth_flags_p = -1;
108 static int hf_auth_flags_t = -1;
110 static gint ett_sap = -1;
111 static gint ett_sap_flags = -1;
112 static gint ett_sap_auth = -1;
113 static gint ett_sap_authf = -1;
115 static dissector_handle_t sdp_handle;
118 dissect_sap(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
121 int sap_version, is_ipv6, is_del, is_enc, is_comp, addr_len;
129 proto_item *si, *sif;
130 proto_tree *sap_tree, *sap_flags_tree;
132 if (check_col(pinfo->cinfo, COL_PROTOCOL))
133 col_set_str(pinfo->cinfo, COL_PROTOCOL, "SAP");
134 if (check_col(pinfo->cinfo, COL_INFO))
135 col_clear(pinfo->cinfo, COL_INFO);
137 vers_flags = tvb_get_guint8(tvb, offset);
138 is_ipv6 = vers_flags&MCAST_SAP_BIT_A;
139 is_del = vers_flags&MCAST_SAP_BIT_T;
140 is_enc = vers_flags&MCAST_SAP_BIT_E;
141 is_comp = vers_flags&MCAST_SAP_BIT_C;
143 sap_version = (vers_flags&MCAST_SAP_VERSION_MASK)>>MCAST_SAP_VERSION_SHIFT;
144 addr_len = (is_ipv6) ? sizeof(struct e_in6_addr) : 4;
146 if (check_col(pinfo->cinfo, COL_INFO)) {
147 col_add_fstr(pinfo->cinfo, COL_INFO, "%s (v%u)",
148 (is_del) ? "Deletion" : "Announcement", sap_version);
152 si = proto_tree_add_item(tree, proto_sap, tvb, offset, -1, FALSE);
153 sap_tree = proto_item_add_subtree(si, ett_sap);
155 sif = proto_tree_add_uint(sap_tree, hf_sap_flags, tvb, offset, 1, vers_flags);
156 sap_flags_tree = proto_item_add_subtree(sif, ett_sap_flags);
157 proto_tree_add_uint(sap_flags_tree, hf_sap_flags_v, tvb, offset, 1, vers_flags);
158 proto_tree_add_boolean(sap_flags_tree, hf_sap_flags_a, tvb, offset, 1, vers_flags);
159 proto_tree_add_boolean(sap_flags_tree, hf_sap_flags_r, tvb, offset, 1, vers_flags);
160 proto_tree_add_boolean(sap_flags_tree, hf_sap_flags_t, tvb, offset, 1, vers_flags);
161 proto_tree_add_boolean(sap_flags_tree, hf_sap_flags_e, tvb, offset, 1, vers_flags);
162 proto_tree_add_boolean(sap_flags_tree, hf_sap_flags_c, tvb, offset, 1, vers_flags);
165 auth_len = tvb_get_guint8(tvb, offset);
166 proto_tree_add_text(sap_tree, tvb, offset, 1, "Authentication Length: %u", auth_len);
169 tmp1 = tvb_get_ntohs(tvb, offset);
170 proto_tree_add_text(sap_tree, tvb, offset, 2, "Message Identifier Hash: 0x%x", tmp1);
173 addr = tvb_get_ptr(tvb, offset, addr_len);
174 proto_tree_add_text(sap_tree, tvb, offset, addr_len, "Originating Source: %s",
175 (is_ipv6) ? ip6_to_str((const struct e_in6_addr*)addr) : ip_to_str(addr));
178 /* Authentication data lives in its own subtree */
180 guint32 auth_data_len;
181 proto_item *sdi, *sai;
182 proto_tree *sa_tree, *saf_tree;
186 auth_data_len = auth_len * sizeof(guint32);
188 sdi = proto_tree_add_item(sap_tree, hf_auth_data, tvb, offset, auth_data_len, FALSE);
189 sa_tree = proto_item_add_subtree(sdi, ett_sap_auth);
191 auth_flags = tvb_get_guint8(tvb, offset);
192 sai = proto_tree_add_uint(sa_tree, hf_auth_flags, tvb, offset, 1, auth_flags);
193 saf_tree = proto_item_add_subtree(sai, ett_sap_authf);
194 proto_tree_add_uint(saf_tree, hf_auth_flags_v, tvb, offset, 1, auth_flags);
195 proto_tree_add_boolean(saf_tree, hf_auth_flags_p, tvb, offset, 1, auth_flags);
196 proto_tree_add_uint(saf_tree, hf_auth_flags_t, tvb, offset, 1, auth_flags);
198 has_pad = auth_flags&MCAST_SAP_AUTH_BIT_P;
200 pad_len = tvb_get_guint8(tvb, offset+auth_data_len-1);
202 proto_tree_add_text(sa_tree, tvb, offset+1, auth_data_len-pad_len-1,
203 "Authentication subheader: (%u byte%s)",
204 auth_data_len-1, plurality(auth_data_len-1, "", "s"));
206 proto_tree_add_text(sa_tree, tvb, offset+auth_data_len-pad_len, pad_len,
207 "Authentication data padding: (%u byte%s)",
208 pad_len, plurality(pad_len, "", "s"));
209 proto_tree_add_text(sa_tree, tvb, offset+auth_data_len-1, 1,
210 "Authentication data pad count: %u byte%s",
211 pad_len, plurality(pad_len, "", "s"));
214 offset += auth_data_len;
216 if (is_enc || is_comp) {
218 if (is_enc && is_comp) mangle = "compressed and encrypted";
219 else if (is_enc) mangle = "encrypted";
220 else mangle = "compressed";
221 proto_tree_add_text(sap_tree, tvb, offset, -1,
222 "The rest of the packet is %s", mangle);
226 /* Do we have the optional payload type aka. MIME content specifier */
227 if (tvb_strneql(tvb, offset, "v=", strlen("v="))) {
232 remaining_len = tvb_length_remaining(tvb, offset);
233 if (remaining_len == 0) {
235 * "tvb_strneql()" failed because there was no
236 * data left in the packet.
238 * Set the remaining length to 1, so that
239 * we throw the appropriate exception in
240 * "tvb_get_ptr()", rather than displaying
245 pt_string_len = tvb_strnlen(tvb, offset, remaining_len);
246 if (pt_string_len == -1) {
248 * We didn't find a terminating '\0'; run to the
251 pt_string_len = remaining_len;
252 pt_len = pt_string_len;
255 * Include the '\0' in the total item length.
257 pt_len = pt_string_len + 1;
259 proto_tree_add_text(sap_tree, tvb, offset, pt_len,
260 "Payload type: %.*s", pt_string_len,
261 tvb_get_ptr(tvb, offset, pt_string_len));
267 next_tvb = tvb_new_subset(tvb, offset, -1, -1);
268 call_dissector(sdp_handle, next_tvb, pinfo, tree);
273 void proto_register_sap(void)
276 static hf_register_info hf[] = {
278 { "Flags", "sap.flags",
279 FT_UINT8, BASE_HEX, NULL, 0x0,
280 "Bits in the beginning of the SAP header", HFILL }},
283 { "Version Number", "sap.flags.v",
284 FT_UINT8, BASE_DEC, VALS(mcast_sap_ver), MCAST_SAP_VERSION_MASK,
285 "3 bit version field in the SAP header", HFILL }},
288 { "Address Type", "sap.flags.a",
289 FT_BOOLEAN, 8, TFS(&mcast_sap_address_type), MCAST_SAP_BIT_A,
290 "Originating source address type", HFILL }},
293 { "Reserved", "sap.flags.r",
294 FT_BOOLEAN, 8, TFS(&flags_set_truth), MCAST_SAP_BIT_R,
295 "Reserved", HFILL }},
298 { "Message Type", "sap.flags.t",
299 FT_BOOLEAN, 8, TFS(&mcast_sap_message_type), MCAST_SAP_BIT_T,
300 "Announcement type", HFILL }},
303 { "Encryption Bit", "sap.flags.e",
304 FT_BOOLEAN, 8, TFS(&mcast_sap_crypt_type), MCAST_SAP_BIT_E,
305 "Encryption", HFILL }},
308 { "Compression Bit", "sap.flags.c",
309 FT_BOOLEAN, 8, TFS(&mcast_sap_comp_type), MCAST_SAP_BIT_C,
310 "Compression", HFILL }},
313 { "Authentication data", "sap.auth",
314 FT_NONE, BASE_NONE, NULL, 0x0,
315 "Auth data", HFILL }},
318 { "Authentication data flags", "sap.auth.flags",
319 FT_UINT8, BASE_HEX, NULL, 0x0,
320 "Auth flags", HFILL }},
323 { "Version Number", "sap.auth.flags.v",
324 FT_UINT8, BASE_DEC, VALS(&mcast_sap_auth_ver), MCAST_SAP_VERSION_MASK,
328 { "Padding Bit", "sap.auth.flags.p",
329 FT_BOOLEAN, 8, TFS(&mcast_sap_auth_pad), MCAST_SAP_AUTH_BIT_P,
330 "Compression", HFILL }},
333 { "Authentication Type", "sap.auth.flags.t",
334 FT_UINT8, BASE_DEC, VALS(&mcast_sap_auth_type), MCAST_SAP_AUTH_TYPE_MASK,
335 "Auth type", HFILL }}
337 static gint *ett[] = {
344 proto_sap = proto_register_protocol("Session Announcement Protocol", "SAP",
346 proto_register_field_array(proto_sap, hf, array_length(hf));
347 proto_register_subtree_array(ett, array_length(ett));
351 proto_reg_handoff_sap(void)
353 dissector_handle_t sap_handle;
355 sap_handle = create_dissector_handle(dissect_sap, proto_sap);
356 dissector_add("udp.port", UDP_PORT_SAP, sap_handle);
359 * Get a handle for the SDP dissector.
361 sdp_handle = find_dissector("sdp");