dtls_srtp_driver.c

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/*
 * dtls_srtp_driver.c
 *
 * test driver for DTLS-SRTP functions
 *
 * David McGrew
 * Cisco Systems, Inc.
 */
/*
 *	
 * Copyright (c) 2001-2006 Cisco Systems, Inc.
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 
 *   Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * 
 *   Redistributions in binary form must reproduce the above
 *   copyright notice, this list of conditions and the following
 *   disclaimer in the documentation and/or other materials provided
 *   with the distribution.
 * 
 *   Neither the name of the Cisco Systems, Inc. nor the names of its
 *   contributors may be used to endorse or promote products derived
 *   from this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

#include <stdio.h>    /* for printf()          */
#include "getopt_s.h" /* for local getopt()    */
#include "srtp_priv.h"

err_status_t 
test_dtls_srtp();

srtp_hdr_t *
srtp_create_test_packet(int pkt_octet_len, uint32_t ssrc);

void
usage(char *prog_name) {
  printf("usage: %s [ -t ][ -c ][ -v ][-d <debug_module> ]* [ -l ]\n"
         "  -d <mod>   turn on debugging module <mod>\n"
         "  -l         list debugging modules\n", prog_name);
  exit(1);
}

int
main(int argc, char *argv[]) {
  unsigned do_list_mods      = 0;
  char q;
  err_status_t err;

  printf("dtls_srtp_driver\n");

  /* initialize srtp library */
  err = srtp_init();
  if (err) {
    printf("error: srtp init failed with error code %d\n", err);
    exit(1);
  }

  /* process input arguments */
  while (1) {
    q = getopt_s(argc, argv, "ld:");
    if (q == -1) 
      break;
    switch (q) {
    case 'l':
      do_list_mods = 1;
      break;
    case 'd':
      err = crypto_kernel_set_debug_module(optarg_s, 1);
      if (err) {
        printf("error: set debug module (%s) failed\n", optarg_s);
        exit(1);
      }  
      break;
    default:
      usage(argv[0]);
    }    
  }

  if (do_list_mods) {
    err = crypto_kernel_list_debug_modules();
    if (err) {
      printf("error: list of debug modules failed\n");
      exit(1);
    }
  }

  printf("testing dtls_srtp...");
  err = test_dtls_srtp();
  if (err) {
    printf("\nerror (code %d)\n", err);
    exit(1);
  }
  printf("passed\n");
  
  return 0;
}


err_status_t
test_dtls_srtp() {
  srtp_hdr_t *test_packet;
  int test_packet_len = 80;
  srtp_t s;
  srtp_policy_t policy;
  uint8_t key[SRTP_MAX_KEY_LEN];
  uint8_t salt[SRTP_MAX_KEY_LEN];
  unsigned int key_len, salt_len;
  srtp_profile_t profile;
  err_status_t err;

  /* create a 'null' SRTP session */
  err = srtp_create(&s, NULL);
  if (err) 
    return err;

  /* 
   * verify that packet-processing functions behave properly - we
   * expect that these functions will return err_status_no_ctx
   */
  test_packet = srtp_create_test_packet(80, 0xa5a5a5a5);
  if (test_packet == NULL) 
    return err_status_alloc_fail;
  err = srtp_protect(s, test_packet, &test_packet_len);
  if (err != err_status_no_ctx) {
    printf("wrong return value from srtp_protect() (got code %d)\n", 
	   err);
    return err_status_fail;
  }
  err = srtp_unprotect(s, test_packet, &test_packet_len);
  if (err != err_status_no_ctx) {
    printf("wrong return value from srtp_unprotect() (got code %d)\n", 
	   err);
    return err_status_fail;
  }
  err = srtp_protect_rtcp(s, test_packet, &test_packet_len);
  if (err != err_status_no_ctx) {
    printf("wrong return value from srtp_protect_rtcp() (got code %d)\n", 
	   err);
    return err_status_fail;
  }
  err = srtp_unprotect_rtcp(s, test_packet, &test_packet_len);
  if (err != err_status_no_ctx) {
    printf("wrong return value from srtp_unprotect_rtcp() (got code %d)\n", 
	   err);
    return err_status_fail;
  }


  /* 
   * set keys to known values for testing
   */
  profile = srtp_profile_aes128_cm_sha1_80;
  key_len = srtp_profile_get_master_key_length(profile);
  salt_len = srtp_profile_get_master_salt_length(profile);
  memset(key, 0xff, key_len);
  memset(salt, 0xee, salt_len);
  append_salt_to_key(key, key_len, salt, salt_len);
  policy.key  = key;

  /* initialize SRTP policy from profile  */
  err = crypto_policy_set_from_profile_for_rtp(&policy.rtp, profile);
  if (err) return err;
  err = crypto_policy_set_from_profile_for_rtcp(&policy.rtcp, profile);
  if (err) return err;
  policy.ssrc.type  = ssrc_any_inbound;
  policy.next = NULL;
    
  err = srtp_add_stream(s, &policy);
  if (err)
    return err;
  
  return err_status_ok;
}



/*
 * srtp_create_test_packet(len, ssrc) returns a pointer to a
 * (malloced) example RTP packet whose data field has the length given
 * by pkt_octet_len and the SSRC value ssrc.  The total length of the
 * packet is twelve octets longer, since the header is at the
 * beginning.  There is room at the end of the packet for a trailer,
 * and the four octets following the packet are filled with 0xff
 * values to enable testing for overwrites.
 *
 * note that the location of the test packet can (and should) be
 * deallocated with the free() call once it is no longer needed.
 */

srtp_hdr_t *
srtp_create_test_packet(int pkt_octet_len, uint32_t ssrc) {
  int i;
  uint8_t *buffer;
  srtp_hdr_t *hdr;
  int bytes_in_hdr = 12;

  /* allocate memory for test packet */
  hdr = malloc(pkt_octet_len + bytes_in_hdr
	       + SRTP_MAX_TRAILER_LEN + 4);
  if (!hdr)
    return NULL;
  
  hdr->version = 2;              /* RTP version two     */
  hdr->p    = 0;                 /* no padding needed   */
  hdr->x    = 0;                 /* no header extension */
  hdr->cc   = 0;                 /* no CSRCs            */
  hdr->m    = 0;                 /* marker bit          */
  hdr->pt   = 0xf;               /* payload type        */
  hdr->seq  = htons(0x1234);     /* sequence number     */
  hdr->ts   = htonl(0xdecafbad); /* timestamp           */
  hdr->ssrc = htonl(ssrc);       /* synch. source       */

  buffer = (uint8_t *)hdr;
  buffer += bytes_in_hdr;

  /* set RTP data to 0xab */
  for (i=0; i < pkt_octet_len; i++)
    *buffer++ = 0xab;

  /* set post-data value to 0xffff to enable overrun checking */
  for (i=0; i < SRTP_MAX_TRAILER_LEN+4; i++)
    *buffer++ = 0xff;

  return hdr;
}