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 #if HAVE_THREADS && GNUTLS_VERSION_NUMBER <= 0x020b00
  39 #include <gcrypt.h>
  40 #include "libavutil/thread.h"
  41 GCRY_THREAD_OPTION_PTHREAD_IMPL;
  42 #endif
  43
  44 typedef struct TLSContext {
  45     const AVClass *class;
  46     TLSShared tls_shared;
  47     gnutls_session_t session;
  48     gnutls_certificate_credentials_t cred;
  49     int need_shutdown;
  50 } TLSContext;
  51
  52 void ff_gnutls_init(void)
  53 {
  54     avpriv_lock_avformat();
  55 #if HAVE_THREADS && GNUTLS_VERSION_NUMBER < 0x020b00
  56     if (gcry_control(GCRYCTL_ANY_INITIALIZATION_P) == 0)
  57         gcry_control(GCRYCTL_SET_THREAD_CBS, &gcry_threads_pthread);
  58 #endif
  59     gnutls_global_init();
  60     avpriv_unlock_avformat();
  61 }
  62
  63 void ff_gnutls_deinit(void)
  64 {
  65     avpriv_lock_avformat();
  66     gnutls_global_deinit();
  67     avpriv_unlock_avformat();
  68 }
  69
  70 static int print_tls_error(URLContext *h, int ret)
  71 {
  72     switch (ret) {
  73     case GNUTLS_E_AGAIN:
  74     case GNUTLS_E_INTERRUPTED:
  75     case GNUTLS_E_PREMATURE_TERMINATION:
  76         break;
  77     case GNUTLS_E_WARNING_ALERT_RECEIVED:
  78         av_log(h, AV_LOG_WARNING, "%s\n", gnutls_strerror(ret));
  79         break;
  80     default:
  81         av_log(h, AV_LOG_ERROR, "%s\n", gnutls_strerror(ret));
  82         break;
  83     }
  84     return AVERROR(EIO);
  85 }
  86
  87 static int tls_close(URLContext *h)
  88 {
  89     TLSContext *c = h->priv_data;
  90     if (c->need_shutdown)
  91         gnutls_bye(c->session, GNUTLS_SHUT_WR);
  92     if (c->session)
  93         gnutls_deinit(c->session);
  94     if (c->cred)
  95         gnutls_certificate_free_credentials(c->cred);
  96     if (c->tls_shared.tcp)
  97         ffurl_close(c->tls_shared.tcp);
  98     ff_gnutls_deinit();
  99     return 0;
 100 }
 101
 102 static ssize_t gnutls_url_pull(gnutls_transport_ptr_t transport,
 103                                void *buf, size_t len)
 104 {
 105     URLContext *h = (URLContext*) transport;
 106     int ret = ffurl_read(h, buf, len);
 107     if (ret >= 0)
 108         return ret;
 109     if (ret == AVERROR_EXIT)
 110         return 0;
 111     errno = EIO;
 112     return -1;
 113 }
 114
 115 static ssize_t gnutls_url_push(gnutls_transport_ptr_t transport,
 116                                const void *buf, size_t len)
 117 {
 118     URLContext *h = (URLContext*) transport;
 119     int ret = ffurl_write(h, buf, len);
 120     if (ret >= 0)
 121         return ret;
 122     if (ret == AVERROR_EXIT)
 123         return 0;
 124     errno = EIO;
 125     return -1;
 126 }
 127
 128 static int tls_open(URLContext *h, const char *uri, int flags, AVDictionary **options)
 129 {
 130     TLSContext *p = h->priv_data;
 131     TLSShared *c = &p->tls_shared;
 132     int ret;
 133
 134     ff_gnutls_init();
 135
 136     if ((ret = ff_tls_open_underlying(c, h, uri, options)) < 0)
 137         goto fail;
 138
 139     gnutls_init(&p->session, c->listen ? GNUTLS_SERVER : GNUTLS_CLIENT);
 140     if (!c->listen && !c->numerichost)
 141         gnutls_server_name_set(p->session, GNUTLS_NAME_DNS, c->host, strlen(c->host));
 142     gnutls_certificate_allocate_credentials(&p->cred);
 143     if (c->ca_file) {
 144         ret = gnutls_certificate_set_x509_trust_file(p->cred, c->ca_file, GNUTLS_X509_FMT_PEM);
 145         if (ret < 0)
 146             av_log(h, AV_LOG_ERROR, "%s\n", gnutls_strerror(ret));
 147     }
 148 #if GNUTLS_VERSION_NUMBER >= 0x030020
 149     else
 150         gnutls_certificate_set_x509_system_trust(p->cred);
 151 #endif
 152     gnutls_certificate_set_verify_flags(p->cred, c->verify ?
 153                                         GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT : 0);
 154     if (c->cert_file && c->key_file) {
 155         ret = gnutls_certificate_set_x509_key_file(p->cred,
 156                                                    c->cert_file, c->key_file,
 157                                                    GNUTLS_X509_FMT_PEM);
 158         if (ret < 0) {
 159             av_log(h, AV_LOG_ERROR,
 160                    "Unable to set cert/key files %s and %s: %s\n",
 161                    c->cert_file, c->key_file, gnutls_strerror(ret));
 162             ret = AVERROR(EIO);
 163             goto fail;
 164         }
 165     } else if (c->cert_file || c->key_file)
 166         av_log(h, AV_LOG_ERROR, "cert and key required\n");
 167     gnutls_credentials_set(p->session, GNUTLS_CRD_CERTIFICATE, p->cred);
 168     gnutls_transport_set_pull_function(p->session, gnutls_url_pull);
 169     gnutls_transport_set_push_function(p->session, gnutls_url_push);
 170     gnutls_transport_set_ptr(p->session, c->tcp);
 171     gnutls_priority_set_direct(p->session, "NORMAL", NULL);
 172     ret = gnutls_handshake(p->session);
 173     if (ret) {
 174         ret = print_tls_error(h, ret);
 175         goto fail;
 176     }
 177     p->need_shutdown = 1;
 178     if (c->verify) {
 179         unsigned int status, cert_list_size;
 180         gnutls_x509_crt_t cert;
 181         const gnutls_datum_t *cert_list;
 182         if ((ret = gnutls_certificate_verify_peers2(p->session, &status)) < 0) {
 183             av_log(h, AV_LOG_ERROR, "Unable to verify peer certificate: %s\n",
 184                                     gnutls_strerror(ret));
 185             ret = AVERROR(EIO);
 186             goto fail;
 187         }
 188         if (status & GNUTLS_CERT_INVALID) {
 189             av_log(h, AV_LOG_ERROR, "Peer certificate failed verification\n");
 190             ret = AVERROR(EIO);
 191             goto fail;
 192         }
 193         if (gnutls_certificate_type_get(p->session) != GNUTLS_CRT_X509) {
 194             av_log(h, AV_LOG_ERROR, "Unsupported certificate type\n");
 195             ret = AVERROR(EIO);
 196             goto fail;
 197         }
 198         gnutls_x509_crt_init(&cert);
 199         cert_list = gnutls_certificate_get_peers(p->session, &cert_list_size);
 200         gnutls_x509_crt_import(cert, cert_list, GNUTLS_X509_FMT_DER);
 201         ret = gnutls_x509_crt_check_hostname(cert, c->host);
 202         gnutls_x509_crt_deinit(cert);
 203         if (!ret) {
 204             av_log(h, AV_LOG_ERROR,
 205                    "The certificate's owner does not match hostname %s\n", c->host);
 206             ret = AVERROR(EIO);
 207             goto fail;
 208         }
 209     }
 210
 211     return 0;
 212 fail:
 213     tls_close(h);
 214     return ret;
 215 }
 216
 217 static int tls_read(URLContext *h, uint8_t *buf, int size)
 218 {
 219     TLSContext *c = h->priv_data;
 220     int ret = gnutls_record_recv(c->session, buf, size);
 221     if (ret > 0)
 222         return ret;
 223     if (ret == 0)
 224         return AVERROR_EOF;
 225     return print_tls_error(h, ret);
 226 }
 227
 228 static int tls_write(URLContext *h, const uint8_t *buf, int size)
 229 {
 230     TLSContext *c = h->priv_data;
 231     int ret = gnutls_record_send(c->session, buf, size);
 232     if (ret > 0)
 233         return ret;
 234     if (ret == 0)
 235         return AVERROR_EOF;
 236     return print_tls_error(h, ret);
 237 }
 238
 239 static int tls_get_file_handle(URLContext *h)
 240 {
 241     TLSContext *c = h->priv_data;
 242     return ffurl_get_file_handle(c->tls_shared.tcp);
 243 }
 244
 245 static const AVOption options[] = {
 246     TLS_COMMON_OPTIONS(TLSContext, tls_shared),
 247     { NULL }
 248 };
 249
 250 static const AVClass tls_class = {
 251     .class_name = "tls",
 252     .item_name  = av_default_item_name,
 253     .option     = options,
 254     .version    = LIBAVUTIL_VERSION_INT,
 255 };
 256
 257 const URLProtocol ff_tls_gnutls_protocol = {
 258     .name           = "tls",
 259     .url_open2      = tls_open,
 260     .url_read       = tls_read,
 261     .url_write      = tls_write,
 262     .url_close      = tls_close,
 263     .url_get_file_handle = tls_get_file_handle,
 264     .priv_data_size = sizeof(TLSContext),
 265     .flags          = URL_PROTOCOL_FLAG_NETWORK,
 266     .priv_data_class = &tls_class,
 267 };