git.sesse.net Git - ffmpeg/blob - libavformat/tls_gnutls.c

   1 /*
   2  * TLS/SSL Protocol
   3  * Copyright (c) 2011 Martin Storsjo
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #include <errno.h>
  23
  24 #include <gnutls/gnutls.h>
  25 #include <gnutls/x509.h>
  26
  27 #include "avformat.h"
  28 #include "internal.h"
  29 #include "network.h"
  30 #include "os_support.h"
  31 #include "url.h"
  32 #include "tls.h"
  33 #include "libavcodec/internal.h"
  34 #include "libavutil/avstring.h"
  35 #include "libavutil/opt.h"
  36 #include "libavutil/parseutils.h"
  37
  38 #ifndef GNUTLS_VERSION_NUMBER
  39 #define GNUTLS_VERSION_NUMBER LIBGNUTLS_VERSION_NUMBER
  40 #endif
  41
  42 #if HAVE_THREADS && GNUTLS_VERSION_NUMBER <= 0x020b00
  43 #include <gcrypt.h>
  44 #include "libavutil/thread.h"
  45 GCRY_THREAD_OPTION_PTHREAD_IMPL;
  46 #endif
  47
  48 typedef struct TLSContext {
  49     const AVClass *class;
  50     TLSShared tls_shared;
  51     gnutls_session_t session;
  52     gnutls_certificate_credentials_t cred;
  53     int need_shutdown;
  54 } TLSContext;
  55
  56 void ff_gnutls_init(void)
  57 {
  58     avpriv_lock_avformat();
  59 #if HAVE_THREADS && GNUTLS_VERSION_NUMBER < 0x020b00
  60     if (gcry_control(GCRYCTL_ANY_INITIALIZATION_P) == 0)
  61         gcry_control(GCRYCTL_SET_THREAD_CBS, &gcry_threads_pthread);
  62 #endif
  63     gnutls_global_init();
  64     avpriv_unlock_avformat();
  65 }
  66
  67 void ff_gnutls_deinit(void)
  68 {
  69     avpriv_lock_avformat();
  70     gnutls_global_deinit();
  71     avpriv_unlock_avformat();
  72 }
  73
  74 static int print_tls_error(URLContext *h, int ret)
  75 {
  76     switch (ret) {
  77     case GNUTLS_E_AGAIN:
  78     case GNUTLS_E_INTERRUPTED:
  79 #ifdef GNUTLS_E_PREMATURE_TERMINATION
  80     case GNUTLS_E_PREMATURE_TERMINATION:
  81 #endif
  82         break;
  83     case GNUTLS_E_WARNING_ALERT_RECEIVED:
  84         av_log(h, AV_LOG_WARNING, "%s\n", gnutls_strerror(ret));
  85         break;
  86     default:
  87         av_log(h, AV_LOG_ERROR, "%s\n", gnutls_strerror(ret));
  88         break;
  89     }
  90     return AVERROR(EIO);
  91 }
  92
  93 static int tls_close(URLContext *h)
  94 {
  95     TLSContext *c = h->priv_data;
  96     if (c->need_shutdown)
  97         gnutls_bye(c->session, GNUTLS_SHUT_WR);
  98     if (c->session)
  99         gnutls_deinit(c->session);
 100     if (c->cred)
 101         gnutls_certificate_free_credentials(c->cred);
 102     if (c->tls_shared.tcp)
 103         ffurl_close(c->tls_shared.tcp);
 104     ff_gnutls_deinit();
 105     return 0;
 106 }
 107
 108 static ssize_t gnutls_url_pull(gnutls_transport_ptr_t transport,
 109                                void *buf, size_t len)
 110 {
 111     URLContext *h = (URLContext*) transport;
 112     int ret = ffurl_read(h, buf, len);
 113     if (ret >= 0)
 114         return ret;
 115     if (ret == AVERROR_EXIT)
 116         return 0;
 117     errno = EIO;
 118     return -1;
 119 }
 120
 121 static ssize_t gnutls_url_push(gnutls_transport_ptr_t transport,
 122                                const void *buf, size_t len)
 123 {
 124     URLContext *h = (URLContext*) transport;
 125     int ret = ffurl_write(h, buf, len);
 126     if (ret >= 0)
 127         return ret;
 128     if (ret == AVERROR_EXIT)
 129         return 0;
 130     errno = EIO;
 131     return -1;
 132 }
 133
 134 static int tls_open(URLContext *h, const char *uri, int flags, AVDictionary **options)
 135 {
 136     TLSContext *p = h->priv_data;
 137     TLSShared *c = &p->tls_shared;
 138     int ret;
 139
 140     ff_gnutls_init();
 141
 142     if ((ret = ff_tls_open_underlying(c, h, uri, options)) < 0)
 143         goto fail;
 144
 145     gnutls_init(&p->session, c->listen ? GNUTLS_SERVER : GNUTLS_CLIENT);
 146     if (!c->listen && !c->numerichost)
 147         gnutls_server_name_set(p->session, GNUTLS_NAME_DNS, c->host, strlen(c->host));
 148     gnutls_certificate_allocate_credentials(&p->cred);
 149     if (c->ca_file) {
 150         ret = gnutls_certificate_set_x509_trust_file(p->cred, c->ca_file, GNUTLS_X509_FMT_PEM);
 151         if (ret < 0)
 152             av_log(h, AV_LOG_ERROR, "%s\n", gnutls_strerror(ret));
 153     }
 154 #if GNUTLS_VERSION_NUMBER >= 0x030020
 155     else
 156         gnutls_certificate_set_x509_system_trust(p->cred);
 157 #endif
 158     gnutls_certificate_set_verify_flags(p->cred, c->verify ?
 159                                         GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT : 0);
 160     if (c->cert_file && c->key_file) {
 161         ret = gnutls_certificate_set_x509_key_file(p->cred,
 162                                                    c->cert_file, c->key_file,
 163                                                    GNUTLS_X509_FMT_PEM);
 164         if (ret < 0) {
 165             av_log(h, AV_LOG_ERROR,
 166                    "Unable to set cert/key files %s and %s: %s\n",
 167                    c->cert_file, c->key_file, gnutls_strerror(ret));
 168             ret = AVERROR(EIO);
 169             goto fail;
 170         }
 171     } else if (c->cert_file || c->key_file)
 172         av_log(h, AV_LOG_ERROR, "cert and key required\n");
 173     gnutls_credentials_set(p->session, GNUTLS_CRD_CERTIFICATE, p->cred);
 174     gnutls_transport_set_pull_function(p->session, gnutls_url_pull);
 175     gnutls_transport_set_push_function(p->session, gnutls_url_push);
 176     gnutls_transport_set_ptr(p->session, c->tcp);
 177     gnutls_priority_set_direct(p->session, "NORMAL", NULL);
 178     ret = gnutls_handshake(p->session);
 179     if (ret) {
 180         ret = print_tls_error(h, ret);
 181         goto fail;
 182     }
 183     p->need_shutdown = 1;
 184     if (c->verify) {
 185         unsigned int status, cert_list_size;
 186         gnutls_x509_crt_t cert;
 187         const gnutls_datum_t *cert_list;
 188         if ((ret = gnutls_certificate_verify_peers2(p->session, &status)) < 0) {
 189             av_log(h, AV_LOG_ERROR, "Unable to verify peer certificate: %s\n",
 190                                     gnutls_strerror(ret));
 191             ret = AVERROR(EIO);
 192             goto fail;
 193         }
 194         if (status & GNUTLS_CERT_INVALID) {
 195             av_log(h, AV_LOG_ERROR, "Peer certificate failed verification\n");
 196             ret = AVERROR(EIO);
 197             goto fail;
 198         }
 199         if (gnutls_certificate_type_get(p->session) != GNUTLS_CRT_X509) {
 200             av_log(h, AV_LOG_ERROR, "Unsupported certificate type\n");
 201             ret = AVERROR(EIO);
 202             goto fail;
 203         }
 204         gnutls_x509_crt_init(&cert);
 205         cert_list = gnutls_certificate_get_peers(p->session, &cert_list_size);
 206         gnutls_x509_crt_import(cert, cert_list, GNUTLS_X509_FMT_DER);
 207         ret = gnutls_x509_crt_check_hostname(cert, c->host);
 208         gnutls_x509_crt_deinit(cert);
 209         if (!ret) {
 210             av_log(h, AV_LOG_ERROR,
 211                    "The certificate's owner does not match hostname %s\n", c->host);
 212             ret = AVERROR(EIO);
 213             goto fail;
 214         }
 215     }
 216
 217     return 0;
 218 fail:
 219     tls_close(h);
 220     return ret;
 221 }
 222
 223 static int tls_read(URLContext *h, uint8_t *buf, int size)
 224 {
 225     TLSContext *c = h->priv_data;
 226     int ret = gnutls_record_recv(c->session, buf, size);
 227     if (ret > 0)
 228         return ret;
 229     if (ret == 0)
 230         return AVERROR_EOF;
 231     return print_tls_error(h, ret);
 232 }
 233
 234 static int tls_write(URLContext *h, const uint8_t *buf, int size)
 235 {
 236     TLSContext *c = h->priv_data;
 237     int ret = gnutls_record_send(c->session, buf, size);
 238     if (ret > 0)
 239         return ret;
 240     if (ret == 0)
 241         return AVERROR_EOF;
 242     return print_tls_error(h, ret);
 243 }
 244
 245 static int tls_get_file_handle(URLContext *h)
 246 {
 247     TLSContext *c = h->priv_data;
 248     return ffurl_get_file_handle(c->tls_shared.tcp);
 249 }
 250
 251 static const AVOption options[] = {
 252     TLS_COMMON_OPTIONS(TLSContext, tls_shared),
 253     { NULL }
 254 };
 255
 256 static const AVClass tls_class = {
 257     .class_name = "tls",
 258     .item_name  = av_default_item_name,
 259     .option     = options,
 260     .version    = LIBAVUTIL_VERSION_INT,
 261 };
 262
 263 const URLProtocol ff_tls_gnutls_protocol = {
 264     .name           = "tls",
 265     .url_open2      = tls_open,
 266     .url_read       = tls_read,
 267     .url_write      = tls_write,
 268     .url_close      = tls_close,
 269     .url_get_file_handle = tls_get_file_handle,
 270     .priv_data_size = sizeof(TLSContext),
 271     .flags          = URL_PROTOCOL_FLAG_NETWORK,
 272     .priv_data_class = &tls_class,
 273 };