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 GCRY_THREAD_OPTION_PTHREAD_IMPL;
  41 #endif
  42
  43 typedef struct TLSContext {
  44     const AVClass *class;
  45     TLSShared tls_shared;
  46     gnutls_session_t session;
  47     gnutls_certificate_credentials_t cred;
  48     int need_shutdown;
  49 } TLSContext;
  50
  51 void ff_gnutls_init(void)
  52 {
  53     avpriv_lock_avformat();
  54 #if HAVE_THREADS && GNUTLS_VERSION_NUMBER < 0x020b00
  55     if (gcry_control(GCRYCTL_ANY_INITIALIZATION_P) == 0)
  56         gcry_control(GCRYCTL_SET_THREAD_CBS, &gcry_threads_pthread);
  57 #endif
  58     gnutls_global_init();
  59     avpriv_unlock_avformat();
  60 }
  61
  62 void ff_gnutls_deinit(void)
  63 {
  64     avpriv_lock_avformat();
  65     gnutls_global_deinit();
  66     avpriv_unlock_avformat();
  67 }
  68
  69 static int print_tls_error(URLContext *h, int ret)
  70 {
  71     switch (ret) {
  72     case GNUTLS_E_AGAIN:
  73     case GNUTLS_E_INTERRUPTED:
  74         break;
  75     case GNUTLS_E_WARNING_ALERT_RECEIVED:
  76         av_log(h, AV_LOG_WARNING, "%s\n", gnutls_strerror(ret));
  77         break;
  78     default:
  79         av_log(h, AV_LOG_ERROR, "%s\n", gnutls_strerror(ret));
  80         break;
  81     }
  82     return AVERROR(EIO);
  83 }
  84
  85 static int tls_close(URLContext *h)
  86 {
  87     TLSContext *c = h->priv_data;
  88     if (c->need_shutdown)
  89         gnutls_bye(c->session, GNUTLS_SHUT_RDWR);
  90     if (c->session)
  91         gnutls_deinit(c->session);
  92     if (c->cred)
  93         gnutls_certificate_free_credentials(c->cred);
  94     if (c->tls_shared.tcp)
  95         ffurl_close(c->tls_shared.tcp);
  96     ff_gnutls_deinit();
  97     return 0;
  98 }
  99
 100 static ssize_t gnutls_url_pull(gnutls_transport_ptr_t transport,
 101                                void *buf, size_t len)
 102 {
 103     URLContext *h = (URLContext*) transport;
 104     int ret = ffurl_read(h, buf, len);
 105     if (ret >= 0)
 106         return ret;
 107     if (ret == AVERROR_EXIT)
 108         return 0;
 109     errno = EIO;
 110     return -1;
 111 }
 112
 113 static ssize_t gnutls_url_push(gnutls_transport_ptr_t transport,
 114                                const void *buf, size_t len)
 115 {
 116     URLContext *h = (URLContext*) transport;
 117     int ret = ffurl_write(h, buf, len);
 118     if (ret >= 0)
 119         return ret;
 120     if (ret == AVERROR_EXIT)
 121         return 0;
 122     errno = EIO;
 123     return -1;
 124 }
 125
 126 static int tls_open(URLContext *h, const char *uri, int flags, AVDictionary **options)
 127 {
 128     TLSContext *p = h->priv_data;
 129     TLSShared *c = &p->tls_shared;
 130     int ret;
 131
 132     ff_gnutls_init();
 133
 134     if ((ret = ff_tls_open_underlying(c, h, uri, options)) < 0)
 135         goto fail;
 136
 137     gnutls_init(&p->session, c->listen ? GNUTLS_SERVER : GNUTLS_CLIENT);
 138     if (!c->listen && !c->numerichost)
 139         gnutls_server_name_set(p->session, GNUTLS_NAME_DNS, c->host, strlen(c->host));
 140     gnutls_certificate_allocate_credentials(&p->cred);
 141     if (c->ca_file) {
 142         ret = gnutls_certificate_set_x509_trust_file(p->cred, c->ca_file, GNUTLS_X509_FMT_PEM);
 143         if (ret < 0)
 144             av_log(h, AV_LOG_ERROR, "%s\n", gnutls_strerror(ret));
 145     }
 146 #if GNUTLS_VERSION_MAJOR >= 3
 147     else
 148         gnutls_certificate_set_x509_system_trust(p->cred);
 149 #endif
 150     gnutls_certificate_set_verify_flags(p->cred, c->verify ?
 151                                         GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT : 0);
 152     if (c->cert_file && c->key_file) {
 153         ret = gnutls_certificate_set_x509_key_file(p->cred,
 154                                                    c->cert_file, c->key_file,
 155                                                    GNUTLS_X509_FMT_PEM);
 156         if (ret < 0) {
 157             av_log(h, AV_LOG_ERROR,
 158                    "Unable to set cert/key files %s and %s: %s\n",
 159                    c->cert_file, c->key_file, gnutls_strerror(ret));
 160             ret = AVERROR(EIO);
 161             goto fail;
 162         }
 163     } else if (c->cert_file || c->key_file)
 164         av_log(h, AV_LOG_ERROR, "cert and key required\n");
 165     gnutls_credentials_set(p->session, GNUTLS_CRD_CERTIFICATE, p->cred);
 166     gnutls_transport_set_pull_function(p->session, gnutls_url_pull);
 167     gnutls_transport_set_push_function(p->session, gnutls_url_push);
 168     gnutls_transport_set_ptr(p->session, c->tcp);
 169     gnutls_priority_set_direct(p->session, "NORMAL", NULL);
 170     ret = gnutls_handshake(p->session);
 171     if (ret) {
 172         ret = print_tls_error(h, ret);
 173         goto fail;
 174     }
 175     p->need_shutdown = 1;
 176     if (c->verify) {
 177         unsigned int status, cert_list_size;
 178         gnutls_x509_crt_t cert;
 179         const gnutls_datum_t *cert_list;
 180         if ((ret = gnutls_certificate_verify_peers2(p->session, &status)) < 0) {
 181             av_log(h, AV_LOG_ERROR, "Unable to verify peer certificate: %s\n",
 182                                     gnutls_strerror(ret));
 183             ret = AVERROR(EIO);
 184             goto fail;
 185         }
 186         if (status & GNUTLS_CERT_INVALID) {
 187             av_log(h, AV_LOG_ERROR, "Peer certificate failed verification\n");
 188             ret = AVERROR(EIO);
 189             goto fail;
 190         }
 191         if (gnutls_certificate_type_get(p->session) != GNUTLS_CRT_X509) {
 192             av_log(h, AV_LOG_ERROR, "Unsupported certificate type\n");
 193             ret = AVERROR(EIO);
 194             goto fail;
 195         }
 196         gnutls_x509_crt_init(&cert);
 197         cert_list = gnutls_certificate_get_peers(p->session, &cert_list_size);
 198         gnutls_x509_crt_import(cert, cert_list, GNUTLS_X509_FMT_DER);
 199         ret = gnutls_x509_crt_check_hostname(cert, c->host);
 200         gnutls_x509_crt_deinit(cert);
 201         if (!ret) {
 202             av_log(h, AV_LOG_ERROR,
 203                    "The certificate's owner does not match hostname %s\n", c->host);
 204             ret = AVERROR(EIO);
 205             goto fail;
 206         }
 207     }
 208
 209     return 0;
 210 fail:
 211     tls_close(h);
 212     return ret;
 213 }
 214
 215 static int tls_read(URLContext *h, uint8_t *buf, int size)
 216 {
 217     TLSContext *c = h->priv_data;
 218     int ret = gnutls_record_recv(c->session, buf, size);
 219     if (ret > 0)
 220         return ret;
 221     if (ret == 0)
 222         return AVERROR_EOF;
 223     return print_tls_error(h, ret);
 224 }
 225
 226 static int tls_write(URLContext *h, const uint8_t *buf, int size)
 227 {
 228     TLSContext *c = h->priv_data;
 229     int ret = gnutls_record_send(c->session, buf, size);
 230     if (ret > 0)
 231         return ret;
 232     if (ret == 0)
 233         return AVERROR_EOF;
 234     return print_tls_error(h, ret);
 235 }
 236
 237 static const AVOption options[] = {
 238     TLS_COMMON_OPTIONS(TLSContext, tls_shared),
 239     { NULL }
 240 };
 241
 242 static const AVClass tls_class = {
 243     .class_name = "tls",
 244     .item_name  = av_default_item_name,
 245     .option     = options,
 246     .version    = LIBAVUTIL_VERSION_INT,
 247 };
 248
 249 URLProtocol ff_tls_gnutls_protocol = {
 250     .name           = "tls",
 251     .url_open2      = tls_open,
 252     .url_read       = tls_read,
 253     .url_write      = tls_write,
 254     .url_close      = tls_close,
 255     .priv_data_size = sizeof(TLSContext),
 256     .flags          = URL_PROTOCOL_FLAG_NETWORK,
 257     .priv_data_class = &tls_class,
 258 };