michael@0: /*
michael@0: Copyright (c) 2007, Adobe Systems, Incorporated
michael@0: All rights reserved.
michael@0: 
michael@0: Redistribution and use in source and binary forms, with or without
michael@0: modification, are permitted provided that the following conditions are
michael@0: met:
michael@0: 
michael@0: * Redistributions of source code must retain the above copyright
michael@0:   notice, this list of conditions and the following disclaimer.
michael@0: 
michael@0: * Redistributions in binary form must reproduce the above copyright
michael@0:   notice, this list of conditions and the following disclaimer in the
michael@0:   documentation and/or other materials provided with the distribution.
michael@0: 
michael@0: * Neither the name of Adobe Systems, Network Resonance nor the names of its
michael@0:   contributors may be used to endorse or promote products derived from
michael@0:   this software without specific prior written permission.
michael@0: 
michael@0: THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
michael@0: "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
michael@0: LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
michael@0: A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
michael@0: OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
michael@0: SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
michael@0: LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
michael@0: DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
michael@0: THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
michael@0: (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
michael@0: OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
michael@0: */
michael@0: 
michael@0: 
michael@0: static char *RCSSTRING __UNUSED__="$Id: stun_build.c,v 1.2 2008/04/28 18:21:30 ekr Exp $";
michael@0: 
michael@0: #include <csi_platform.h>
michael@0: #include <assert.h>
michael@0: #include <errno.h>
michael@0: #include <stdio.h>
michael@0: #include <string.h>
michael@0: #include <ctype.h>
michael@0: 
michael@0: #include "nr_api.h"
michael@0: #include "stun.h"
michael@0: #include "registry.h"
michael@0: #include "stun_reg.h"
michael@0: #include "nr_crypto.h"
michael@0: 
michael@0: 
michael@0: /* draft-ietf-behave-rfc3489bis-10.txt S 7.1 */
michael@0: /* draft-ietf-behave-rfc3489bis-10.txt S 10.1.1 */
michael@0: /* note that S 10.1.1 states the message MUST include MESSAGE-INTEGRITY
michael@0:  * and USERNAME, but that's not correct -- for instance ICE keepalive
michael@0:  * messages don't include these (See draft-ietf-mmusic-ice-18.txt S 10:
michael@0:  * "If STUN is being used for keepalives, a STUN Binding Indication is
michael@0:  * used.  The Indication MUST NOT utilize any authentication mechanism")
michael@0:  */
michael@0: int
michael@0: nr_stun_form_request_or_indication(int mode, int msg_type, nr_stun_message **msg)
michael@0: {
michael@0:    int r,_status;
michael@0:    nr_stun_message *req = 0;
michael@0: 
michael@0:    assert(NR_STUN_GET_TYPE_CLASS(msg_type) == NR_CLASS_REQUEST
michael@0:        || NR_STUN_GET_TYPE_CLASS(msg_type) == NR_CLASS_INDICATION);
michael@0: 
michael@0:    *msg = 0;
michael@0: 
michael@0:    if ((r=nr_stun_message_create(&req)))
michael@0:        ABORT(r);
michael@0: 
michael@0:    req->header.type = msg_type;
michael@0: 
michael@0:    nr_crypto_random_bytes((UCHAR*)&req->header.id,sizeof(req->header.id));
michael@0: 
michael@0:    switch (mode) {
michael@0:    default:
michael@0:        req->header.magic_cookie = NR_STUN_MAGIC_COOKIE;
michael@0: 
michael@0:        if ((r=nr_stun_message_add_fingerprint_attribute(req)))
michael@0:            ABORT(r);
michael@0: 
michael@0:        break;
michael@0: 
michael@0: #ifdef USE_STUND_0_96
michael@0:    case NR_STUN_MODE_STUND_0_96:
michael@0:        req->header.magic_cookie = NR_STUN_MAGIC_COOKIE2;
michael@0: 
michael@0:        /* actually, stund 0.96 just ignores the fingerprint
michael@0:         * attribute, but don't bother to send it */
michael@0: 
michael@0:        break;
michael@0: #endif /* USE_STUND_0_96 */
michael@0: 
michael@0:    }
michael@0: 
michael@0:    *msg = req;
michael@0: 
michael@0:    _status=0;
michael@0:  abort:
michael@0:    if (_status) RFREE(req);
michael@0:    return _status;
michael@0: }
michael@0: 
michael@0: int
michael@0: nr_stun_build_req_lt_auth(nr_stun_client_stun_binding_request_params *params, nr_stun_message **msg)
michael@0: {
michael@0:    int r,_status;
michael@0:    nr_stun_message *req = 0;
michael@0: 
michael@0:    if ((r=nr_stun_form_request_or_indication(NR_STUN_MODE_STUN, NR_STUN_MSG_BINDING_REQUEST, &req)))
michael@0:        ABORT(r);
michael@0: 
michael@0:    if ((r=nr_stun_message_add_username_attribute(req, params->username)))
michael@0:        ABORT(r);
michael@0: 
michael@0:    if (params->realm && params->nonce) {
michael@0:        if ((r=nr_stun_message_add_realm_attribute(req, params->realm)))
michael@0:            ABORT(r);
michael@0: 
michael@0:        if ((r=nr_stun_message_add_nonce_attribute(req, params->nonce)))
michael@0:            ABORT(r);
michael@0: 
michael@0:        if ((r=nr_stun_message_add_message_integrity_attribute(req, params->password)))
michael@0:            ABORT(r);
michael@0:    }
michael@0: 
michael@0:    *msg = req;
michael@0: 
michael@0:    _status=0;
michael@0:  abort:
michael@0:    if (_status) nr_stun_message_destroy(&req);
michael@0:    return _status;
michael@0: }
michael@0: 
michael@0: int
michael@0: nr_stun_build_req_st_auth(nr_stun_client_stun_binding_request_params *params, nr_stun_message **msg)
michael@0: {
michael@0:    int r,_status;
michael@0:    nr_stun_message *req = 0;
michael@0: 
michael@0:    if ((r=nr_stun_form_request_or_indication(NR_STUN_MODE_STUN, NR_STUN_MSG_BINDING_REQUEST, &req)))
michael@0:        ABORT(r);
michael@0: 
michael@0:    if ((r=nr_stun_message_add_username_attribute(req, params->username)))
michael@0:        ABORT(r);
michael@0: 
michael@0:    if (params->password) {
michael@0:        if ((r=nr_stun_message_add_message_integrity_attribute(req, params->password)))
michael@0:            ABORT(r);
michael@0:    }
michael@0: 
michael@0:    *msg = req;
michael@0: 
michael@0:    _status=0;
michael@0:  abort:
michael@0:    if (_status) nr_stun_message_destroy(&req);
michael@0:    return _status;
michael@0: }
michael@0: 
michael@0: int
michael@0: nr_stun_build_req_no_auth(nr_stun_client_stun_binding_request_params *params, nr_stun_message **msg)
michael@0: {
michael@0:    int r,_status;
michael@0:    nr_stun_message *req = 0;
michael@0: 
michael@0:    if ((r=nr_stun_form_request_or_indication(NR_STUN_MODE_STUN, NR_STUN_MSG_BINDING_REQUEST, &req)))
michael@0:        ABORT(r);
michael@0: 
michael@0:    *msg = req;
michael@0: 
michael@0:    _status=0;
michael@0:  abort:
michael@0:    if (_status) nr_stun_message_destroy(&req);
michael@0:    return _status;
michael@0: }
michael@0: 
michael@0: int
michael@0: nr_stun_build_keepalive(nr_stun_client_stun_keepalive_params *params, nr_stun_message **msg)
michael@0: {
michael@0:    int r,_status;
michael@0:    nr_stun_message *ind = 0;
michael@0: 
michael@0:    if ((r=nr_stun_form_request_or_indication(NR_STUN_MODE_STUN, NR_STUN_MSG_BINDING_INDICATION, &ind)))
michael@0:        ABORT(r);
michael@0: 
michael@0:    *msg = ind;
michael@0: 
michael@0:    _status=0;
michael@0:  abort:
michael@0:    if (_status) nr_stun_message_destroy(&ind);
michael@0:    return _status;
michael@0: }
michael@0: 
michael@0: #ifdef USE_STUND_0_96
michael@0: int
michael@0: nr_stun_build_req_stund_0_96(nr_stun_client_stun_binding_request_stund_0_96_params *params, nr_stun_message **msg)
michael@0: {
michael@0:     int r,_status;
michael@0:     nr_stun_message *req = 0;
michael@0: 
michael@0:     if ((r=nr_stun_form_request_or_indication(NR_STUN_MODE_STUND_0_96, NR_STUN_MSG_BINDING_REQUEST, &req)))
michael@0:         ABORT(r);
michael@0: 
michael@0:     if ((r=nr_stun_message_add_change_request_attribute(req, 0)))
michael@0:         ABORT(r);
michael@0: 
michael@0:     assert(! nr_stun_message_has_attribute(req, NR_STUN_ATTR_USERNAME, 0));
michael@0:     assert(! nr_stun_message_has_attribute(req, NR_STUN_ATTR_MESSAGE_INTEGRITY, 0));
michael@0: 
michael@0:     *msg = req;
michael@0: 
michael@0:    _status=0;
michael@0:  abort:
michael@0:    if (_status) nr_stun_message_destroy(&req);
michael@0:    return _status;
michael@0: }
michael@0: #endif /* USE_STUND_0_96 */
michael@0: 
michael@0: #ifdef USE_ICE
michael@0: int
michael@0: nr_stun_build_use_candidate(nr_stun_client_ice_use_candidate_params *params, nr_stun_message **msg)
michael@0: {
michael@0:    int r,_status;
michael@0:    nr_stun_message *req = 0;
michael@0: 
michael@0:    if ((r=nr_stun_form_request_or_indication(NR_STUN_MODE_STUN, NR_STUN_MSG_BINDING_REQUEST, &req)))
michael@0:        ABORT(r);
michael@0: 
michael@0:    if ((r=nr_stun_message_add_username_attribute(req, params->username)))
michael@0:        ABORT(r);
michael@0: 
michael@0:    if ((r=nr_stun_message_add_message_integrity_attribute(req, &params->password)))
michael@0:        ABORT(r);
michael@0: 
michael@0:    if ((r=nr_stun_message_add_use_candidate_attribute(req)))
michael@0:        ABORT(r);
michael@0: 
michael@0:    if ((r=nr_stun_message_add_priority_attribute(req, params->priority)))
michael@0:        ABORT(r);
michael@0: 
michael@0:    if ((r=nr_stun_message_add_ice_controlling_attribute(req, params->tiebreaker)))
michael@0:      ABORT(r);
michael@0: 
michael@0:    *msg = req;
michael@0: 
michael@0:    _status=0;
michael@0:  abort:
michael@0:    if (_status) nr_stun_message_destroy(&req);
michael@0:    return _status;
michael@0: }
michael@0: 
michael@0: int
michael@0: nr_stun_build_req_ice(nr_stun_client_ice_binding_request_params *params, nr_stun_message **msg)
michael@0: {
michael@0:    int r,_status;
michael@0:    nr_stun_message *req = 0;
michael@0: 
michael@0:    if ((r=nr_stun_form_request_or_indication(NR_STUN_MODE_STUN, NR_STUN_MSG_BINDING_REQUEST, &req)))
michael@0:        ABORT(r);
michael@0: 
michael@0:    if ((r=nr_stun_message_add_username_attribute(req, params->username)))
michael@0:        ABORT(r);
michael@0: 
michael@0:    if ((r=nr_stun_message_add_message_integrity_attribute(req, &params->password)))
michael@0:        ABORT(r);
michael@0: 
michael@0:    if ((r=nr_stun_message_add_priority_attribute(req, params->priority)))
michael@0:        ABORT(r);
michael@0: 
michael@0:    switch (params->control) {
michael@0:    case NR_ICE_CONTROLLING:
michael@0:        if ((r=nr_stun_message_add_ice_controlling_attribute(req, params->tiebreaker)))
michael@0:            ABORT(r);
michael@0:        break;
michael@0:    case NR_ICE_CONTROLLED:
michael@0:        if ((r=nr_stun_message_add_ice_controlled_attribute(req, params->tiebreaker)))
michael@0:            ABORT(r);
michael@0:        break;
michael@0:    default:
michael@0:        assert(0);
michael@0:        ABORT(R_INTERNAL);
michael@0:    }
michael@0: 
michael@0:    *msg = req;
michael@0: 
michael@0:    _status=0;
michael@0:  abort:
michael@0:    if (_status) nr_stun_message_destroy(&req);
michael@0:    return _status;
michael@0: }
michael@0: #endif /* USE_ICE */
michael@0: 
michael@0: #ifdef USE_TURN
michael@0: 
michael@0: #ifndef __isascii
michael@0: #define __isascii(c) (((c) & ~0x7F) == 0)
michael@0: #endif
michael@0: 
michael@0: /* Long-term passwords are computed over the key:
michael@0: 
michael@0:             key = MD5(username ":" realm ":" SASLprep(password))
michael@0: 
michael@0:    Per RFC 5389 S 15.4
michael@0: */
michael@0: int
michael@0: nr_stun_compute_lt_message_integrity_password(const char *username, const char *realm,
michael@0:                                               Data *password, Data *hmac_key)
michael@0: {
michael@0:   char digest_input[1000];
michael@0:   int i;
michael@0:   int r, _status;
michael@0:   size_t len;
michael@0: 
michael@0:   /* First check that the password is ASCII. We are supposed to
michael@0:      SASLprep but we don't support this yet
michael@0:      TODO(ekr@rtfm.com): Add SASLprep for password.
michael@0:  */
michael@0:   for (i=0; i<password->len; i++) {
michael@0:     if (!__isascii(password->data[i]))
michael@0:       ABORT(R_BAD_DATA);
michael@0:   }
michael@0: 
michael@0:   if (hmac_key->len < 16)
michael@0:     ABORT(R_BAD_ARGS);
michael@0: 
michael@0:   snprintf(digest_input, sizeof(digest_input), "%s:%s:", username, realm);
michael@0:   if ((sizeof(digest_input) - strlen(digest_input)) < password->len)
michael@0:     ABORT(R_BAD_DATA);
michael@0: 
michael@0:   len = strlen(digest_input);
michael@0:   memcpy(digest_input + len, password->data, password->len);
michael@0: 
michael@0: 
michael@0:   if (r=nr_crypto_md5((UCHAR *)digest_input, len + password->len, hmac_key->data))
michael@0:     ABORT(r);
michael@0:   hmac_key->len=16;
michael@0: 
michael@0:   _status=0;
michael@0: abort:
michael@0:   return(_status);
michael@0: }
michael@0: 
michael@0: static int
michael@0: nr_stun_build_auth_params(nr_stun_client_auth_params *auth, nr_stun_message *req)
michael@0: {
michael@0:   int r, _status;
michael@0:   UCHAR hmac_key_d[16];
michael@0:   Data hmac_key;
michael@0: 
michael@0:   ATTACH_DATA(hmac_key, hmac_key_d);
michael@0: 
michael@0:   if (!auth->authenticate)
michael@0:     goto done;
michael@0: 
michael@0:   assert(auth->username);
michael@0:   assert(auth->password.len);
michael@0:   assert(auth->realm);
michael@0:   assert(auth->nonce);
michael@0: 
michael@0:   if (r=nr_stun_compute_lt_message_integrity_password(auth->username,
michael@0:                                                       auth->realm,
michael@0:                                                       &auth->password,
michael@0:                                                       &hmac_key))
michael@0:     ABORT(r);
michael@0: 
michael@0:   if (!auth->username) {
michael@0:     r_log(NR_LOG_STUN, LOG_WARNING, "STUN authentication requested but no username provided");
michael@0:     ABORT(R_INTERNAL);
michael@0:   }
michael@0: 
michael@0:   if (!auth->password.len) {
michael@0:     r_log(NR_LOG_STUN, LOG_WARNING, "STUN authentication requested but no password provided");
michael@0:     ABORT(R_INTERNAL);
michael@0:   }
michael@0: 
michael@0:   if (!auth->realm) {
michael@0:     r_log(NR_LOG_STUN, LOG_WARNING, "STUN authentication requested but no realm provided");
michael@0:     ABORT(R_INTERNAL);
michael@0:   }
michael@0: 
michael@0:   if (!auth->nonce) {
michael@0:     r_log(NR_LOG_STUN, LOG_WARNING, "STUN authentication requested but no nonce provided");
michael@0:     ABORT(R_INTERNAL);
michael@0:   }
michael@0: 
michael@0:   if ((r=nr_stun_message_add_username_attribute(req, auth->username)))
michael@0:     ABORT(r);
michael@0: 
michael@0:   if ((r=nr_stun_message_add_realm_attribute(req, auth->realm)))
michael@0:     ABORT(r);
michael@0: 
michael@0:   if ((r=nr_stun_message_add_nonce_attribute(req, auth->nonce)))
michael@0:     ABORT(r);
michael@0: 
michael@0:   if ((r=nr_stun_message_add_message_integrity_attribute(req, &hmac_key)))
michael@0:     ABORT(r);
michael@0: 
michael@0: done:
michael@0:   _status=0;
michael@0: abort:
michael@0:   return(_status);
michael@0: }
michael@0: 
michael@0: int
michael@0: nr_stun_build_allocate_request(nr_stun_client_auth_params *auth, nr_stun_client_allocate_request_params *params, nr_stun_message **msg)
michael@0: {
michael@0:    int r,_status;
michael@0:    nr_stun_message *req = 0;
michael@0: 
michael@0:    if ((r=nr_stun_form_request_or_indication(NR_STUN_MODE_STUN, NR_STUN_MSG_ALLOCATE_REQUEST, &req)))
michael@0:        ABORT(r);
michael@0: 
michael@0:    if ((r=nr_stun_message_add_requested_transport_attribute(req, NR_STUN_ATTR_REQUESTED_TRANSPORT_UDP)))
michael@0:        ABORT(r);
michael@0: 
michael@0:   if ((r=nr_stun_message_add_lifetime_attribute(req, params->lifetime_secs)))
michael@0:        ABORT(r);
michael@0: 
michael@0:   /* TODO(ekr@rtfm.com): Add the SOFTWARE attribute (Firefox bug 857666) */
michael@0: 
michael@0:   if ((r=nr_stun_build_auth_params(auth, req)))
michael@0:        ABORT(r);
michael@0: 
michael@0:    *msg = req;
michael@0: 
michael@0:    _status=0;
michael@0:  abort:
michael@0:    if (_status) nr_stun_message_destroy(&req);
michael@0:    return _status;
michael@0: }
michael@0: 
michael@0: 
michael@0: int nr_stun_build_refresh_request(nr_stun_client_auth_params *auth, nr_stun_client_refresh_request_params *params, nr_stun_message **msg)
michael@0: {
michael@0:    int r,_status;
michael@0:    nr_stun_message *req = 0;
michael@0: 
michael@0:    if ((r=nr_stun_form_request_or_indication(NR_STUN_MODE_STUN, NR_STUN_MSG_REFRESH_REQUEST, &req)))
michael@0:        ABORT(r);
michael@0: 
michael@0:   if ((r=nr_stun_message_add_lifetime_attribute(req, params->lifetime_secs)))
michael@0:        ABORT(r);
michael@0: 
michael@0: 
michael@0:   /* TODO(ekr@rtfm.com): Add the SOFTWARE attribute (Firefox bug 857666) */
michael@0: 
michael@0:   if ((r=nr_stun_build_auth_params(auth, req)))
michael@0:        ABORT(r);
michael@0: 
michael@0:   *msg = req;
michael@0: 
michael@0:    _status=0;
michael@0:  abort:
michael@0:    if (_status) nr_stun_message_destroy(&req);
michael@0:    return _status;
michael@0: }
michael@0: 
michael@0: 
michael@0: int nr_stun_build_permission_request(nr_stun_client_auth_params *auth, nr_stun_client_permission_request_params *params, nr_stun_message **msg)
michael@0: {
michael@0:    int r,_status;
michael@0:    nr_stun_message *req = 0;
michael@0: 
michael@0:    if ((r=nr_stun_form_request_or_indication(NR_STUN_MODE_STUN, NR_STUN_MSG_PERMISSION_REQUEST, &req)))
michael@0:        ABORT(r);
michael@0: 
michael@0:    if ((r=nr_stun_message_add_xor_peer_address_attribute(req, &params->remote_addr)))
michael@0:        ABORT(r);
michael@0: 
michael@0:    if ((r=nr_stun_build_auth_params(auth, req)))
michael@0:        ABORT(r);
michael@0: 
michael@0:    *msg = req;
michael@0: 
michael@0:    _status=0;
michael@0:  abort:
michael@0:    if (_status) nr_stun_message_destroy(&req);
michael@0:    return _status;
michael@0: }
michael@0: 
michael@0: int
michael@0: nr_stun_build_send_indication(nr_stun_client_send_indication_params *params, nr_stun_message **msg)
michael@0: {
michael@0:    int r,_status;
michael@0:    nr_stun_message *ind = 0;
michael@0: 
michael@0:    if ((r=nr_stun_form_request_or_indication(NR_STUN_MODE_STUN, NR_STUN_MSG_SEND_INDICATION, &ind)))
michael@0:        ABORT(r);
michael@0: 
michael@0:    if ((r=nr_stun_message_add_xor_peer_address_attribute(ind, &params->remote_addr)))
michael@0:        ABORT(r);
michael@0: 
michael@0:    if ((r=nr_stun_message_add_data_attribute(ind, params->data.data, params->data.len)))
michael@0:        ABORT(r);
michael@0: 
michael@0:    *msg = ind;
michael@0: 
michael@0:    _status=0;
michael@0:  abort:
michael@0:    if (_status) nr_stun_message_destroy(&ind);
michael@0:    return _status;
michael@0: }
michael@0: 
michael@0: int
michael@0: nr_stun_build_data_indication(nr_stun_client_data_indication_params *params, nr_stun_message **msg)
michael@0: {
michael@0:    int r,_status;
michael@0:    nr_stun_message *ind = 0;
michael@0: 
michael@0:    if ((r=nr_stun_form_request_or_indication(NR_STUN_MODE_STUN, NR_STUN_MSG_DATA_INDICATION, &ind)))
michael@0:        ABORT(r);
michael@0: 
michael@0:    if ((r=nr_stun_message_add_xor_peer_address_attribute(ind, &params->remote_addr)))
michael@0:        ABORT(r);
michael@0: 
michael@0:    if ((r=nr_stun_message_add_data_attribute(ind, params->data.data, params->data.len)))
michael@0:        ABORT(r);
michael@0: 
michael@0:    *msg = ind;
michael@0: 
michael@0:    _status=0;
michael@0:  abort:
michael@0:    if (_status) nr_stun_message_destroy(&ind);
michael@0:    return _status;
michael@0: }
michael@0: 
michael@0: #endif /* USE_TURN */
michael@0: 
michael@0: /* draft-ietf-behave-rfc3489bis-10.txt S 7.3.1.1 */
michael@0: int
michael@0: nr_stun_form_success_response(nr_stun_message *req, nr_transport_addr *from, Data *password, nr_stun_message *res)
michael@0: {
michael@0:     int r,_status;
michael@0:     int request_method;
michael@0:     char server_name[NR_STUN_MAX_SERVER_BYTES+1]; /* +1 for \0 */
michael@0: 
michael@0:     /* set up information for default response */
michael@0: 
michael@0:     request_method = NR_STUN_GET_TYPE_METHOD(req->header.type);
michael@0:     res->header.type = NR_STUN_TYPE(request_method, NR_CLASS_RESPONSE);
michael@0:     res->header.magic_cookie = req->header.magic_cookie;
michael@0:     memcpy(&res->header.id, &req->header.id, sizeof(res->header.id));
michael@0: 
michael@0:     r_log(NR_LOG_STUN, LOG_DEBUG, "Mapped Address = %s", from->as_string);
michael@0: 
michael@0:     if ((r=nr_stun_message_add_xor_mapped_address_attribute(res, from)))
michael@0:         ABORT(r);
michael@0: 
michael@0:     if (!NR_reg_get_string(NR_STUN_REG_PREF_SERVER_NAME, server_name, sizeof(server_name))) {
michael@0:         if ((r=nr_stun_message_add_server_attribute(res, server_name)))
michael@0:             ABORT(r);
michael@0:     }
michael@0: 
michael@0:     if (res->header.magic_cookie == NR_STUN_MAGIC_COOKIE) {
michael@0:         if (password != 0) {
michael@0:             if ((r=nr_stun_message_add_message_integrity_attribute(res, password)))
michael@0:                 ABORT(r);
michael@0:         }
michael@0: 
michael@0:         if ((r=nr_stun_message_add_fingerprint_attribute(res)))
michael@0:             ABORT(r);
michael@0:     }
michael@0: 
michael@0:     _status=0;
michael@0:  abort:
michael@0:     return _status;
michael@0: }
michael@0: 
michael@0: /* draft-ietf-behave-rfc3489bis-10.txt S 7.3.1.1 */
michael@0: void
michael@0: nr_stun_form_error_response(nr_stun_message *req, nr_stun_message* res, int number, char* msg)
michael@0: {
michael@0:     char *str;
michael@0:     int request_method;
michael@0:     char server_name[NR_STUN_MAX_SERVER_BYTES+1]; /* +1 for \0 */
michael@0: 
michael@0:     if (number < 300 || number > 699)
michael@0:         number = 500;
michael@0: 
michael@0:     r_log(NR_LOG_STUN, LOG_INFO, "Responding with error %d: %s", number, msg);
michael@0: 
michael@0:     request_method = NR_STUN_GET_TYPE_METHOD(req->header.type);
michael@0:     res->header.type = NR_STUN_TYPE(request_method, NR_CLASS_ERROR_RESPONSE);
michael@0:     res->header.magic_cookie = req->header.magic_cookie;
michael@0:     memcpy(&res->header.id, &req->header.id, sizeof(res->header.id));
michael@0: 
michael@0:     /* during development we should never see 500s (hopefully not in deployment either) */
michael@0: 
michael@0:     str = 0;
michael@0:     switch (number) {
michael@0:     case 300:  str = "Try Alternate";       break;
michael@0:     case 400:  str = "Bad Request";         break;
michael@0:     case 401:  str = "Unauthorized";        break;
michael@0:     case 420:  str = "Unknown Attribute";   break;
michael@0:     case 438:  str = "Stale Nonce";         break;
michael@0: #ifdef USE_ICE
michael@0:     case 487:  str = "Role Conflict";       break;
michael@0: #endif
michael@0:     case 500:  str = "Server Error";        break;
michael@0:     }
michael@0:     if (str == 0) {
michael@0:         str = "Unknown";
michael@0:     }
michael@0: 
michael@0:     if (nr_stun_message_add_error_code_attribute(res, number, str)) {
michael@0:          assert(0);  /* should never happen */
michael@0:     }
michael@0: 
michael@0:     if (!NR_reg_get_string(NR_STUN_REG_PREF_SERVER_NAME, server_name, sizeof(server_name))) {
michael@0:         nr_stun_message_add_server_attribute(res, server_name);
michael@0:     }
michael@0: }
michael@0: