tls.c
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1 /*
2  * TLS/SSL Protocol
3  * Copyright (c) 2011 Martin Storsjo
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "avformat.h"
23 #include "url.h"
24 #include "libavutil/avstring.h"
25 #if CONFIG_GNUTLS
26 #include <gnutls/gnutls.h>
27 #define TLS_read(c, buf, size) gnutls_record_recv(c->session, buf, size)
28 #define TLS_write(c, buf, size) gnutls_record_send(c->session, buf, size)
29 #define TLS_shutdown(c) gnutls_bye(c->session, GNUTLS_SHUT_RDWR)
30 #define TLS_free(c) do { \
31  if (c->session) \
32  gnutls_deinit(c->session); \
33  if (c->cred) \
34  gnutls_certificate_free_credentials(c->cred); \
35  } while (0)
36 #elif CONFIG_OPENSSL
37 #include <openssl/bio.h>
38 #include <openssl/ssl.h>
39 #include <openssl/err.h>
40 #define TLS_read(c, buf, size) SSL_read(c->ssl, buf, size)
41 #define TLS_write(c, buf, size) SSL_write(c->ssl, buf, size)
42 #define TLS_shutdown(c) SSL_shutdown(c->ssl)
43 #define TLS_free(c) do { \
44  if (c->ssl) \
45  SSL_free(c->ssl); \
46  if (c->ctx) \
47  SSL_CTX_free(c->ctx); \
48  } while (0)
49 #endif
50 #include "network.h"
51 #include "os_support.h"
52 #include "internal.h"
53 #if HAVE_POLL_H
54 #include <poll.h>
55 #endif
56 
57 typedef struct {
58  const AVClass *class;
60 #if CONFIG_GNUTLS
61  gnutls_session_t session;
62  gnutls_certificate_credentials_t cred;
63 #elif CONFIG_OPENSSL
64  SSL_CTX *ctx;
65  SSL *ssl;
66 #endif
67  int fd;
68 } TLSContext;
69 
70 static int do_tls_poll(URLContext *h, int ret)
71 {
72  TLSContext *c = h->priv_data;
73  struct pollfd p = { c->fd, 0, 0 };
74 #if CONFIG_GNUTLS
75  if (ret != GNUTLS_E_AGAIN && ret != GNUTLS_E_INTERRUPTED) {
76  av_log(h, AV_LOG_ERROR, "%s\n", gnutls_strerror(ret));
77  return AVERROR(EIO);
78  }
79  if (gnutls_record_get_direction(c->session))
80  p.events = POLLOUT;
81  else
82  p.events = POLLIN;
83 #elif CONFIG_OPENSSL
84  ret = SSL_get_error(c->ssl, ret);
85  if (ret == SSL_ERROR_WANT_READ) {
86  p.events = POLLIN;
87  } else if (ret == SSL_ERROR_WANT_WRITE) {
88  p.events = POLLOUT;
89  } else {
90  av_log(h, AV_LOG_ERROR, "%s\n", ERR_error_string(ERR_get_error(), NULL));
91  return AVERROR(EIO);
92  }
93 #endif
94  if (h->flags & AVIO_FLAG_NONBLOCK)
95  return AVERROR(EAGAIN);
96  while (1) {
97  int n = poll(&p, 1, 100);
98  if (n > 0)
99  break;
101  return AVERROR(EINTR);
102  }
103  return 0;
104 }
105 
106 static int tls_open(URLContext *h, const char *uri, int flags)
107 {
108  TLSContext *c = h->priv_data;
109  int ret;
110  int port;
111  char buf[200], host[200];
112  int numerichost = 0;
113  struct addrinfo hints = { 0 }, *ai = NULL;
114  const char *proxy_path;
115  int use_proxy;
116 
117  ff_tls_init();
118 
119  proxy_path = getenv("http_proxy");
120  use_proxy = (proxy_path != NULL) && !getenv("no_proxy") &&
121  av_strstart(proxy_path, "http://", NULL);
122 
123  av_url_split(NULL, 0, NULL, 0, host, sizeof(host), &port, NULL, 0, uri);
124  ff_url_join(buf, sizeof(buf), "tcp", NULL, host, port, NULL);
125 
126  hints.ai_flags = AI_NUMERICHOST;
127  if (!getaddrinfo(host, NULL, &hints, &ai)) {
128  numerichost = 1;
129  freeaddrinfo(ai);
130  }
131 
132  if (use_proxy) {
133  char proxy_host[200], proxy_auth[200], dest[200];
134  int proxy_port;
135  av_url_split(NULL, 0, proxy_auth, sizeof(proxy_auth),
136  proxy_host, sizeof(proxy_host), &proxy_port, NULL, 0,
137  proxy_path);
138  ff_url_join(dest, sizeof(dest), NULL, NULL, host, port, NULL);
139  ff_url_join(buf, sizeof(buf), "httpproxy", proxy_auth, proxy_host,
140  proxy_port, "/%s", dest);
141  }
142 
143  ret = ffurl_open(&c->tcp, buf, AVIO_FLAG_READ_WRITE,
144  &h->interrupt_callback, NULL);
145  if (ret)
146  goto fail;
147  c->fd = ffurl_get_file_handle(c->tcp);
148 
149 #if CONFIG_GNUTLS
150  gnutls_init(&c->session, GNUTLS_CLIENT);
151  if (!numerichost)
152  gnutls_server_name_set(c->session, GNUTLS_NAME_DNS, host, strlen(host));
153  gnutls_certificate_allocate_credentials(&c->cred);
154  gnutls_certificate_set_verify_flags(c->cred, 0);
155  gnutls_credentials_set(c->session, GNUTLS_CRD_CERTIFICATE, c->cred);
156  gnutls_transport_set_ptr(c->session, (gnutls_transport_ptr_t)
157  (intptr_t) c->fd);
158  gnutls_priority_set_direct(c->session, "NORMAL", NULL);
159  while (1) {
160  ret = gnutls_handshake(c->session);
161  if (ret == 0)
162  break;
163  if ((ret = do_tls_poll(h, ret)) < 0)
164  goto fail;
165  }
166 #elif CONFIG_OPENSSL
167  c->ctx = SSL_CTX_new(TLSv1_client_method());
168  if (!c->ctx) {
169  av_log(h, AV_LOG_ERROR, "%s\n", ERR_error_string(ERR_get_error(), NULL));
170  ret = AVERROR(EIO);
171  goto fail;
172  }
173  c->ssl = SSL_new(c->ctx);
174  if (!c->ssl) {
175  av_log(h, AV_LOG_ERROR, "%s\n", ERR_error_string(ERR_get_error(), NULL));
176  ret = AVERROR(EIO);
177  goto fail;
178  }
179  SSL_set_fd(c->ssl, c->fd);
180  if (!numerichost)
181  SSL_set_tlsext_host_name(c->ssl, host);
182  while (1) {
183  ret = SSL_connect(c->ssl);
184  if (ret > 0)
185  break;
186  if (ret == 0) {
187  av_log(h, AV_LOG_ERROR, "Unable to negotiate TLS/SSL session\n");
188  ret = AVERROR(EIO);
189  goto fail;
190  }
191  if ((ret = do_tls_poll(h, ret)) < 0)
192  goto fail;
193  }
194 #endif
195  return 0;
196 fail:
197  TLS_free(c);
198  if (c->tcp)
199  ffurl_close(c->tcp);
200  ff_tls_deinit();
201  return ret;
202 }
203 
204 static int tls_read(URLContext *h, uint8_t *buf, int size)
205 {
206  TLSContext *c = h->priv_data;
207  while (1) {
208  int ret = TLS_read(c, buf, size);
209  if (ret > 0)
210  return ret;
211  if (ret == 0)
212  return AVERROR(EIO);
213  if ((ret = do_tls_poll(h, ret)) < 0)
214  return ret;
215  }
216  return 0;
217 }
218 
219 static int tls_write(URLContext *h, const uint8_t *buf, int size)
220 {
221  TLSContext *c = h->priv_data;
222  while (1) {
223  int ret = TLS_write(c, buf, size);
224  if (ret > 0)
225  return ret;
226  if (ret == 0)
227  return AVERROR(EIO);
228  if ((ret = do_tls_poll(h, ret)) < 0)
229  return ret;
230  }
231  return 0;
232 }
233 
234 static int tls_close(URLContext *h)
235 {
236  TLSContext *c = h->priv_data;
237  TLS_shutdown(c);
238  TLS_free(c);
239  ffurl_close(c->tcp);
240  ff_tls_deinit();
241  return 0;
242 }
243 
245  .name = "tls",
246  .url_open = tls_open,
247  .url_read = tls_read,
248  .url_write = tls_write,
249  .url_close = tls_close,
250  .priv_data_size = sizeof(TLSContext),
252 };