613 lines
21 KiB
C
613 lines
21 KiB
C
/*
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* libZRTP SDK library, implements the ZRTP secure VoIP protocol.
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* Copyright (c) 2006-2009 Philip R. Zimmermann. All rights reserved.
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* Contact: http://philzimmermann.com
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* For licensing and other legal details, see the file zrtp_legal.c.
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*
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* Viktor Krykun <v.krikun at zfoneproject.com>
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*/
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#include "zrtp.h"
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#define _ZTU_ "zrtp responder"
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extern zrtp_status_t _zrtp_machine_start_initiating_secure(zrtp_stream_t *stream);
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/* These functions construct packets for further replies. */
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static zrtp_status_t _prepare_dhpart1(zrtp_stream_t *stream);
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static zrtp_status_t _prepare_confirm1(zrtp_stream_t *stream);
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/* Functions which are used to answer the Initiator's requests */
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static void _send_dhpart1(zrtp_stream_t *stream);
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static void _send_confirm1(zrtp_stream_t *stream);
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/*
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* Parses crypto-components list chosen by the initiator. doesn't perform any
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* tests. Commit was fully checked by previous call of _zrtp_machine_preparse_commit().
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* \exception: Handles all exceptions -- informs user and switches to CLEAR.
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* (zrtp_error_XXX_unsp and zrtp_error_software errors.)
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*/
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static zrtp_status_t _zrtp_machine_process_commit( zrtp_stream_t* stream,
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zrtp_rtp_info_t* packet);
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/*
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* Parses DH packet: check for MitM1, MitM2 attacks and makes a copy of it for further usage.
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* \exception: (MITM attacks, SOFTWARE) Informs user and switches to CLEAR.
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*/
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static zrtp_status_t _zrtp_machine_process_dhpart2( zrtp_stream_t *stream,
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zrtp_rtp_info_t *packet);
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/*
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* Just a wrapper over the protocol::_zrtp_machine_process_confirm().
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* \exception: (AUTH attacks, SOFTWARE) Informs user and switches to CLEAR.
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*/
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static zrtp_status_t _zrtp_machine_process_confirm2( zrtp_stream_t *stream,
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zrtp_rtp_info_t *packet);
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/*===========================================================================*/
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/* State handlers */
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/*===========================================================================*/
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/*---------------------------------------------------------------------------*/
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zrtp_status_t _zrtp_machine_process_while_in_pendingsecure( zrtp_stream_t* stream,
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zrtp_rtp_info_t* packet)
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{
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zrtp_status_t s = zrtp_status_ok;
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switch (packet->type)
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{
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case ZRTP_COMMIT:
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_send_dhpart1(stream);
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break;
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case ZRTP_DHPART2:
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s = _zrtp_machine_process_dhpart2(stream, packet);
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if (zrtp_status_ok != s) {
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break;
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}
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/* Perform Keys generation according to draft 5.6 */
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s = _zrtp_set_public_value(stream, 0);
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if (zrtp_status_ok != s) {
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_zrtp_machine_enter_initiatingerror(stream, zrtp_error_software, 1);
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break;
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}
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s = _prepare_confirm1(stream);
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if (zrtp_status_ok != s) {
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_zrtp_machine_enter_initiatingerror(stream, zrtp_error_software, 1);
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break;
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}
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_zrtp_change_state(stream, ZRTP_STATE_WAIT_CONFIRM2);
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_send_confirm1(stream);
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break;
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case ZRTP_NONE:
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s = zrtp_status_drop;
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break;
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default:
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break;
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}
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return s;
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}
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/*---------------------------------------------------------------------------*/
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zrtp_status_t _zrtp_machine_process_while_in_waitconfirm2( zrtp_stream_t* stream,
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zrtp_rtp_info_t* packet)
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{
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zrtp_status_t status = zrtp_status_ok;
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switch (packet->type)
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{
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case ZRTP_DHPART2:
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if (ZRTP_IS_STREAM_DH(stream)) {
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_send_confirm1(stream);
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}
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break;
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case ZRTP_COMMIT:
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if (ZRTP_IS_STREAM_FAST(stream)) {
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_send_confirm1(stream);
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}
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break;
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case ZRTP_CONFIRM2:
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status = _zrtp_machine_process_confirm2(stream, packet);
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if (zrtp_status_ok == status) {
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_zrtp_packet_send_message(stream, ZRTP_CONFIRM2ACK, NULL);
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status = _zrtp_machine_enter_secure(stream);
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}
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break;
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case ZRTP_NONE:
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status = zrtp_status_drop;
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break;
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default:
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break;
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}
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return status;
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}
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/*===========================================================================*/
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/* States switchers */
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/*===========================================================================*/
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/*---------------------------------------------------------------------------*/
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zrtp_status_t _zrtp_machine_enter_pendingsecure( zrtp_stream_t* stream,
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zrtp_rtp_info_t* packet)
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{
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zrtp_status_t s = zrtp_status_ok;
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ZRTP_LOG(3,(_ZTU_,"\tENTER STATE PENDING SECURE for ID=%u mode=%s state=%s.\n",
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stream->id, zrtp_log_mode2str(stream->mode), zrtp_log_state2str(stream->state)));
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do
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{
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if (!ZRTP_IS_STREAM_MULT(stream)) {
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zrtp_packet_Commit_t *commit = (zrtp_packet_Commit_t*) packet->message;
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stream->session->hash = zrtp_comp_find( ZRTP_CC_HASH,
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zrtp_comp_type2id(ZRTP_CC_HASH, (char*)commit->hash_type),
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stream->zrtp);
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stream->session->blockcipher = zrtp_comp_find( ZRTP_CC_CIPHER,
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zrtp_comp_type2id(ZRTP_CC_CIPHER, (char*)commit->cipher_type),
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stream->zrtp);
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stream->session->authtaglength = zrtp_comp_find( ZRTP_CC_ATL,
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zrtp_comp_type2id(ZRTP_CC_ATL, (char*)commit->auth_tag_length),
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stream->zrtp);
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stream->session->sasscheme = zrtp_comp_find( ZRTP_CC_SAS,
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zrtp_comp_type2id(ZRTP_CC_SAS, (char*)commit->sas_type),
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stream->zrtp);
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ZRTP_LOG(3,(_ZTU_,"\tRemote COMMIT specified following options:\n"));
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ZRTP_LOG(3,(_ZTU_,"\t Hash: %.4s\n", commit->hash_type));
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ZRTP_LOG(3,(_ZTU_,"\t Cipher: %.4s\n", commit->cipher_type));
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ZRTP_LOG(3,(_ZTU_,"\t ATL: %.4s\n", commit->auth_tag_length));
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ZRTP_LOG(3,(_ZTU_,"\t PK scheme: %.4s\n", commit->public_key_type));
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ZRTP_LOG(3,(_ZTU_,"\tVAD scheme: %.4s\n", commit->sas_type));
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}
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if (ZRTP_IS_STREAM_DH(stream)) {
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_zrtp_change_state(stream, ZRTP_STATE_PENDINGSECURE);
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/*
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* If stream->concurrent is set this means that we stopped a concurrent
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* DH stream to break a tie. This can happen when Commit messages are
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* sent by both ZRTP endpoints at the same time, but are received in
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* different media streams. Now current stream has finished DH setup and
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* we can resume the other one.
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*/
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if (stream->concurrent) {
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zrtp_stream_t* tctx = stream->concurrent;
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stream->concurrent = NULL;
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ZRTP_LOG(3,(_ZTU_,"\tRelease2 Concurrent stream=%u ID=%u\n", tctx->id, stream->id));
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_zrtp_machine_start_initiating_secure(tctx);
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}
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s = _zrtp_protocol_init(stream, 0, &stream->protocol);
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if (zrtp_status_ok != s) {
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break;
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}
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s = _zrtp_machine_process_commit(stream, packet); /* doesn't throw exception */
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if (zrtp_status_ok != s) {
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break; /* Software error */
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}
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s = _prepare_dhpart1(stream);
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if (zrtp_status_ok != s) {
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break; /* EH: Always successful */
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}
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_zrtp_machine_process_while_in_pendingsecure(stream, packet);
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if (stream->zrtp->cb.event_cb.on_zrtp_protocol_event) {
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stream->zrtp->cb.event_cb.on_zrtp_protocol_event(stream, ZRTP_EVENT_IS_PENDINGSECURE);
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}
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}
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else
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{
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_zrtp_change_state(stream, ZRTP_STATE_WAIT_CONFIRM2);
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s = _zrtp_protocol_init(stream, 0, &stream->protocol);
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if (zrtp_status_ok != s) {
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break;
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}
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s = _zrtp_machine_process_commit(stream, packet); /* doesn't throw exception */
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if (zrtp_status_ok != s) {
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break; /* Software error */
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}
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s = _zrtp_set_public_value(stream, 0);
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if (zrtp_status_ok != s) {
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break; /* Software error */
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}
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s = _prepare_confirm1(stream);
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if (zrtp_status_ok != s) {
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break; /* Software error */
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}
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_send_confirm1(stream);
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}
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} while (0);
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if (zrtp_status_ok != s) {
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if (stream->protocol) {
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_zrtp_protocol_destroy(stream->protocol);
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stream->protocol = NULL;
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}
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_zrtp_machine_enter_initiatingerror(stream, zrtp_error_software, 1);
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}
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return s;
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}
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/*===========================================================================*/
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/* Packets handlers */
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/*===========================================================================*/
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/*---------------------------------------------------------------------------*/
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static zrtp_status_t _check_commit(zrtp_stream_t *stream, zrtp_packet_Commit_t *commit)
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{
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do {
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/* check PUBLIC KEY TYPE */
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if (0 > zrtp_profile_find( &stream->session->profile,
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ZRTP_CC_PKT,
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zrtp_comp_type2id(ZRTP_CC_PKT, (char*)commit->public_key_type)))
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{
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/* Can't talk to them. ZRTP public key type not supported by current profile */
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ZRTP_LOG(2,(_ZTU_,"\tINFO: PKExch %.4s isn't supported by profile. ID=%u\n",
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commit->public_key_type, stream->id));
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_zrtp_machine_enter_initiatingerror(stream, zrtp_error_pktype_unsp, 1);
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break;
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}
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/* check HASH scheme */
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if ( 0 > zrtp_profile_find( &stream->session->profile,
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ZRTP_CC_HASH,
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zrtp_comp_type2id(ZRTP_CC_HASH, (char*)commit->hash_type)) )
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{
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/* Can't talk to them. ZRTP hash type not supported by current profile */
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ZRTP_LOG(2,(_ZTU_,"\tINFO: Hash %.4s isn't supported by profile. ID=%u\n",
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commit->hash_type, stream->id));
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_zrtp_machine_enter_initiatingerror(stream, zrtp_error_hash_unsp, 1);
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break;
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}
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/* check CIPHER type */
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if ( 0 > zrtp_profile_find( &stream->session->profile,
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ZRTP_CC_CIPHER,
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zrtp_comp_type2id(ZRTP_CC_CIPHER, (char*)commit->cipher_type)) )
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{
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/* Can't talk to them. ZRTP cipher type not supported by current profile */
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ZRTP_LOG(2,(_ZTU_,"\tINFO: Cipher %.4s isn't supported by profile. ID=%u\n",
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commit->cipher_type, stream->id));
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_zrtp_machine_enter_initiatingerror(stream, zrtp_error_cipher_unsp, 1);
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break;
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}
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/* check AUTH TAG LENGTH */
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if ( 0 > zrtp_profile_find( &stream->session->profile,
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ZRTP_CC_ATL,
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zrtp_comp_type2id(ZRTP_CC_ATL, (char*)commit->auth_tag_length)) )
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{
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/* Can't talk to them. ZRTP auth tag length not supported by current profile */
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ZRTP_LOG(2,(_ZTU_,"\tINFO: Authtag %.4s isn't supported by profile. ID=%u\n",
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commit->auth_tag_length, stream->id));
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_zrtp_machine_enter_initiatingerror(stream, zrtp_error_auth_unsp, 1);
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break;
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}
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/* check SAS scheme */
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if ( 0 > zrtp_profile_find( &stream->session->profile,
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ZRTP_CC_SAS,
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zrtp_comp_type2id(ZRTP_CC_SAS, (char*)commit->sas_type)) )
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{
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/* Can't talk to them. ZRTP SAS scheme not supported by current profile */
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ZRTP_LOG(2,(_ZTU_,"\tINFO: SAS %.4s isn't supported by profile. ID=%u\n",
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commit->sas_type, stream->id));
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_zrtp_machine_enter_initiatingerror(stream, zrtp_error_sas_unsp, 1);
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break;
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}
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return zrtp_status_ok;
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} while (0);
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return zrtp_status_fail;
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}
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/*---------------------------------------------------------------------------*/
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zrtp_statemachine_type_t _zrtp_machine_preparse_commit( zrtp_stream_t *stream,
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zrtp_rtp_info_t* packet)
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{
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zrtp_packet_Commit_t *commit = (zrtp_packet_Commit_t*) packet->message;
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zrtp_statemachine_type_t res = ZRTP_STATEMACHINE_RESPONDER;
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zrtp_pktype_id_t his_pkt = zrtp_comp_type2id(ZRTP_CC_PKT, (char*)commit->public_key_type);
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zrtp_stream_mode_t his_mode = (his_pkt == ZRTP_PKTYPE_PRESH) ? ZRTP_STREAM_MODE_PRESHARED : (his_pkt == ZRTP_PKTYPE_MULT) ? ZRTP_STREAM_MODE_MULT : ZRTP_STREAM_MODE_DH;
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ZRTP_LOG(3,(_ZTU_,"\tPreparse incoming COMMIT. Remote peer wants %.4s:%d mode lic=%d peer M=%d.\n",
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commit->public_key_type, his_mode, stream->zrtp->lic_mode, stream->peer_mitm_flag));
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/*
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* Checking crypto components chosen by other peer for stream establishment
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*/
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if (zrtp_status_ok != _check_commit(stream, commit)) {
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return ZRTP_STATEMACHINE_NONE;
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}
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/*
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* Passive ZRTP endpoint can't talk to ZRTP MiTM endpoints.
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*/
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if (!ZRTP_PASSIVE3_TEST(stream)) {
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ZRTP_LOG(2,(_ZTU_,"\tERROR: The endpoint is in passive mode and can't handle"
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" connections with MiTM endpoints. ID=%u\n", stream->id));
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if (stream->zrtp->cb.event_cb.on_zrtp_protocol_event ) {
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stream->zrtp->cb.event_cb.on_zrtp_protocol_event(stream, ZRTP_EVENT_IS_PASSIVE_RESTRICTION);
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}
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_zrtp_machine_enter_initiatingerror(stream, zrtp_error_service_unavail, 1);
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return ZRTP_STATEMACHINE_NONE;
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}
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/*
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* Both sides are in "Initiating" state we need to break the tie:
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* - if both sides wants to use the same scheme - side with lower vh switches to
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* "Responder" state.
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* - if both sides wants to use Preshared scheme and one of the sides are in MiTM mode it
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* should switch to Responder state
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* - if one side wants Preshared and onother one DH - DH should win.
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* - rest of the combinations (DH - Multistream, Preshared - Multistream) are deperecated by the RFC
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*/
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if (ZRTP_STATE_INITIATINGSECURE == stream->state)
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{
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zrtp_pktype_id_t my_pkt = stream->pubkeyscheme->base.id;
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zrtp_stream_mode_t my_mode = (my_pkt == ZRTP_PKTYPE_PRESH) ? ZRTP_STREAM_MODE_PRESHARED : (my_pkt == ZRTP_PKTYPE_MULT) ? ZRTP_STREAM_MODE_MULT : ZRTP_STREAM_MODE_DH;
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ZRTP_LOG(2,(_ZTU_,"\tBoth sides are in INITIATINGSECURE State - BREACK the TIE. ID=%u\n", stream->id));
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if (his_mode == my_mode) {
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if ( (his_mode == ZRTP_STREAM_MODE_PRESHARED) && (stream->peer_mitm_flag || stream->zrtp->is_mitm)) {
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if (stream->peer_mitm_flag) {
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ZRTP_LOG(3,(_ZTU_,"\tWe running in Gneral ZRTP Endpoint mode, but the"
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" remote side is in MiTM - stay Initiating state.\n"));
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res = ZRTP_STATEMACHINE_INITIATOR;
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}
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} else {
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if (zrtp_memcmp( stream->protocol->cc->hv.buffer,
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commit->hv,
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(his_mode == ZRTP_STREAM_MODE_DH) ? ZRTP_HV_SIZE : ZRTP_HV_NONCE_SIZE) > 0) {
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ZRTP_LOG(3,(_ZTU_,"\tWe have Commit with greater HV so stay Initiating state.\n"));
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res = ZRTP_STATEMACHINE_INITIATOR;
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}
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}
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} else {
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if (my_mode == ZRTP_STREAM_MODE_DH) {
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ZRTP_LOG(3,(_ZTU_,"\tOther peer sent Non DH Commit but we want DH - stay Initiating state.\n"));
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res = ZRTP_STATEMACHINE_INITIATOR;
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}
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}
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}
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if (res == ZRTP_STATEMACHINE_RESPONDER)
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{
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/*
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* If other peer wants to switch "Preshared" we must be ready for this. Check
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* for secrets availability and if we can't use "Preshared" we should force other
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* peer to switch to "DH" mode. For this purpose we use our own Commit with DHxK
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* in it. Such Commit should win competition in any case.
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*/
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if ((his_mode == ZRTP_STREAM_MODE_PRESHARED) && !stream->session->secrets.rs1->_cachedflag) {
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ZRTP_LOG(3,(_ZTU_, "\tOther peer wants Preshared mode but we have no secrets.\n"));
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res = ZRTP_STATEMACHINE_INITIATOR;
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}
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/*
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* If other peer wants to switch "Multistream" we must be ready for this. Check
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* for ZRTPSess key availability. If we can't use "Multistream" we should force other
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* peer to switch to "DH" mode. For this purpose we use our own Commit with DHxK
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* in it. Such Commit should win competition in any case.
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*/
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if ((his_mode == ZRTP_STREAM_MODE_MULT) && !stream->session->zrtpsess.length) {
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ZRTP_LOG(3,(_ZTU_,"\tOther peer wants Preshared mode but we have no secrets.\n"));
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res = ZRTP_STATEMACHINE_INITIATOR;
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}
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/*
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* If other peer wants "Full DH" exchange but ZRTP Session key have been already
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* computed - there is no sense in doing this. What is more, ZRTP Specification
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* doesn't allow doing this.
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*/
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if ((his_mode == ZRTP_STREAM_MODE_DH) && (stream->session->zrtpsess.length > 0)) {
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ZRTP_LOG(3,(_ZTU_,"\tOther peer wants DH mode but we have ZRTP session and ready for Multistream.\n"));
|
|
res = ZRTP_STATEMACHINE_NONE;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* If we decided to use Responder's state-machine - only one DH or Preshared stream
|
|
* can be run at the moment so check states.
|
|
*/
|
|
if ((res == ZRTP_STATEMACHINE_RESPONDER) && !_zrtp_can_start_stream(stream, &stream->concurrent, his_mode))
|
|
{
|
|
ZRTP_LOG(3,(_ZTU_,"\tCan't handle COMMIT another DH with ID=%u is in progress.\n", stream->concurrent->id));
|
|
|
|
if ( (stream->concurrent->state <= ZRTP_STATE_INITIATINGSECURE) &&
|
|
(zrtp_memcmp(stream->concurrent->protocol->cc->hv.buffer, commit->hv, ZRTP_HV_SIZE) < 0) )
|
|
{
|
|
ZRTP_LOG(3,(_ZTU_,"\tPossible DEADLOCK Resolving. STOP CONCURRENT"
|
|
" Stream with ID=%u\n",stream->concurrent->id));
|
|
_zrtp_cancel_send_packet_later(stream->concurrent, ZRTP_NONE);
|
|
} else {
|
|
res = ZRTP_STATEMACHINE_NONE;
|
|
}
|
|
}
|
|
|
|
if (res == ZRTP_STATEMACHINE_RESPONDER) {
|
|
ZRTP_LOG(3,(_ZTU_,"\tChosen Responder State-Machine. Change Mode to %s,"
|
|
" pkt to %.4s\n", zrtp_log_mode2str(his_mode), commit->public_key_type));
|
|
stream->mode = his_mode;
|
|
stream->pubkeyscheme = zrtp_comp_find(ZRTP_CC_PKT, his_pkt, stream->zrtp);
|
|
} else {
|
|
ZRTP_LOG(3,(_ZTU_,"\tChosen Initiator State-Machine. Stay in current Mode\n"));
|
|
}
|
|
|
|
return res;
|
|
}
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
zrtp_status_t _zrtp_machine_process_commit(zrtp_stream_t* stream, zrtp_rtp_info_t* packet)
|
|
{
|
|
zrtp_packet_Commit_t *commit = (zrtp_packet_Commit_t*) packet->message;
|
|
|
|
switch (stream->mode)
|
|
{
|
|
case ZRTP_STREAM_MODE_DH:
|
|
zrtp_zstrncpyc( ZSTR_GV(stream->protocol->cc->peer_hv),
|
|
(const char*)commit->hv,
|
|
ZRTP_HV_SIZE);
|
|
break;
|
|
case ZRTP_STREAM_MODE_PRESHARED:
|
|
zrtp_zstrncpyc( ZSTR_GV(stream->protocol->cc->peer_hv),
|
|
(const char*)commit->hv + ZRTP_HV_NONCE_SIZE,
|
|
ZRTP_HV_NONCE_SIZE);
|
|
case ZRTP_STREAM_MODE_MULT:
|
|
zrtp_zstrncpyc( ZSTR_GV(stream->protocol->cc->peer_hv),
|
|
(const char*)commit->hv,
|
|
ZRTP_HV_NONCE_SIZE);
|
|
break;
|
|
default: break;
|
|
}
|
|
|
|
/* Copy Commit packet for further hashing */
|
|
zrtp_memcpy(&stream->messages.peer_commit, commit, zrtp_ntoh16(commit->hdr.length)*4);
|
|
|
|
return zrtp_status_ok;
|
|
}
|
|
|
|
|
|
/*----------------------------------------------------------------------------*/
|
|
static zrtp_status_t _zrtp_machine_process_dhpart2( zrtp_stream_t *stream,
|
|
zrtp_rtp_info_t *packet)
|
|
{
|
|
zrtp_status_t s = zrtp_status_ok;
|
|
zrtp_proto_crypto_t* cc = stream->protocol->cc;
|
|
zrtp_packet_DHPart_t *dhpart2 = (zrtp_packet_DHPart_t*) packet->message;
|
|
void *hash_ctx = NULL;
|
|
|
|
/*
|
|
* Verify hash commitment. (Compare hvi calculated from DH with peer hvi from COMMIT)
|
|
* According to the last version of the internet draft 04a. Hvi should be
|
|
* computed as: hvi=hash(initiator's DHPart2 message | responder's Hello message)
|
|
*/
|
|
hash_ctx = stream->session->hash->hash_begin(stream->session->hash);
|
|
if (!hash_ctx) {
|
|
return zrtp_status_fail;
|
|
}
|
|
|
|
stream->session->hash->hash_update( stream->session->hash,
|
|
hash_ctx,
|
|
(const int8_t*)dhpart2,
|
|
zrtp_ntoh16(dhpart2->hdr.length)*4);
|
|
stream->session->hash->hash_update( stream->session->hash,
|
|
hash_ctx,
|
|
(const int8_t*)&stream->messages.hello,
|
|
zrtp_ntoh16(stream->messages.hello.hdr.length)*4);
|
|
stream->session->hash->hash_end( stream->session->hash,
|
|
hash_ctx,
|
|
ZSTR_GV(cc->hv));
|
|
|
|
/* Truncate comuted hvi to 256 bit. The same length as transferred in Commit message.*/
|
|
cc->hv.length = ZRTP_HASH_SIZE;
|
|
|
|
if (0 != zrtp_zstrcmp(ZSTR_GV(cc->hv), ZSTR_GV(cc->peer_hv))) {
|
|
ZRTP_LOG(1,(_ZTU_,"\tERROR!" ZRTP_MIM2_WARNING_STR " ID=%u\n", stream->id));
|
|
_zrtp_machine_enter_initiatingerror(stream, zrtp_error_possible_mitm2, 1);
|
|
return zrtp_status_fail;
|
|
}
|
|
|
|
/* Validate DH exchange (pvi is 1 or p-1). For DH streams only */
|
|
bnInsertBigBytes(&stream->dh_cc.peer_pv, dhpart2->pv, 0, stream->pubkeyscheme->pv_length);
|
|
|
|
s = stream->pubkeyscheme->validate(stream->pubkeyscheme, &stream->dh_cc.peer_pv);
|
|
if (zrtp_status_ok != s) {
|
|
ZRTP_LOG(1,(_ZTU_,"\tERROR!" ZRTP_MITM1_WARNING_STR " ID=%u\n", stream->id));
|
|
_zrtp_machine_enter_initiatingerror(stream, zrtp_error_possible_mitm1, 1);
|
|
return s;
|
|
}
|
|
|
|
/* Copy DH Part2 packet for future hashing */
|
|
zrtp_memcpy(&stream->messages.peer_dhpart, dhpart2, zrtp_ntoh16(dhpart2->hdr.length)*4);
|
|
|
|
return s;
|
|
}
|
|
|
|
/*----------------------------------------------------------------------------*/
|
|
zrtp_status_t _zrtp_machine_process_confirm2( zrtp_stream_t *stream,
|
|
zrtp_rtp_info_t *packet)
|
|
{
|
|
zrtp_packet_Confirm_t *confirm2 = (zrtp_packet_Confirm_t*) packet->message;
|
|
return _zrtp_machine_process_confirm(stream, confirm2);
|
|
}
|
|
|
|
|
|
/*===========================================================================*/
|
|
/* Packets senders */
|
|
/*===========================================================================*/
|
|
|
|
/*----------------------------------------------------------------------------*/
|
|
static void _send_dhpart1(zrtp_stream_t *stream)
|
|
{
|
|
_zrtp_packet_send_message(stream, ZRTP_DHPART1, &stream->messages.dhpart);
|
|
}
|
|
|
|
static zrtp_status_t _prepare_dhpart1(zrtp_stream_t *stream)
|
|
{
|
|
zrtp_proto_crypto_t* cc = stream->protocol->cc;
|
|
zrtp_packet_DHPart_t *dh1 = &stream->messages.dhpart;
|
|
uint16_t dh_length = (uint16_t)stream->pubkeyscheme->pv_length;
|
|
|
|
zrtp_memcpy(dh1->rs1ID, cc->rs1.id.buffer, ZRTP_RSID_SIZE);
|
|
zrtp_memcpy(dh1->rs2ID, cc->rs2.id.buffer, ZRTP_RSID_SIZE);
|
|
zrtp_memcpy(dh1->auxsID, cc->auxs.id.buffer, ZRTP_RSID_SIZE);
|
|
zrtp_memcpy(dh1->pbxsID, cc->pbxs.id.buffer, ZRTP_RSID_SIZE);
|
|
|
|
bnExtractBigBytes(&stream->dh_cc.pv, dh1->pv, 0, dh_length);
|
|
|
|
_zrtp_packet_fill_msg_hdr( stream,
|
|
ZRTP_DHPART1,
|
|
dh_length + ZRTP_DH_STATIC_SIZE + ZRTP_HMAC_SIZE,
|
|
&dh1->hdr);
|
|
|
|
return zrtp_status_ok;
|
|
}
|
|
|
|
/*----------------------------------------------------------------------------*/
|
|
static void _send_confirm1(zrtp_stream_t *stream)
|
|
{
|
|
_zrtp_packet_send_message(stream, ZRTP_CONFIRM1, &stream->messages.confirm);
|
|
}
|
|
|
|
static zrtp_status_t _prepare_confirm1(zrtp_stream_t *stream)
|
|
{
|
|
zrtp_status_t s = _zrtp_machine_create_confirm(stream, &stream->messages.confirm);
|
|
if (zrtp_status_ok == s) {
|
|
s = _zrtp_packet_fill_msg_hdr( stream,
|
|
ZRTP_CONFIRM1,
|
|
sizeof(zrtp_packet_Confirm_t) - sizeof(zrtp_msg_hdr_t),
|
|
&stream->messages.confirm.hdr);
|
|
}
|
|
|
|
return s;
|
|
}
|