libavformat/tls_openssl.c - third_party/ffmpeg - Git at Google

 /*
  * TLS/SSL Protocol
  * Copyright (c) 2011 Martin Storsjo
  *
  * This file is part of FFmpeg.
  *
  * FFmpeg is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
  * FFmpeg is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
  * License along with FFmpeg; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */

 #include "avformat.h"
 #include "internal.h"
 #include "network.h"
 #include "os_support.h"
 #include "url.h"
 #include "tls.h"
 #include "libavcodec/internal.h"
 #include "libavutil/avstring.h"
 #include "libavutil/avutil.h"
 #include "libavutil/opt.h"
 #include "libavutil/parseutils.h"
 #include "libavutil/thread.h"

 #include <openssl/bio.h>
 #include <openssl/ssl.h>
 #include <openssl/err.h>

 static int openssl_init;

 typedef struct TLSContext {
     const AVClass *class;
     TLSShared tls_shared;
     SSL_CTX *ctx;
     SSL *ssl;
 #if OPENSSL_VERSION_NUMBER >= 0x1010000fL
     BIO_METHOD* url_bio_method;
 #endif
 } TLSContext;

 #if HAVE_THREADS && OPENSSL_VERSION_NUMBER < 0x10100000L
 #include <openssl/crypto.h>
 pthread_mutex_t *openssl_mutexes;
 static void openssl_lock(int mode, int type, const char *file, int line)
 {
     if (mode & CRYPTO_LOCK)
         pthread_mutex_lock(&openssl_mutexes[type]);
     else
         pthread_mutex_unlock(&openssl_mutexes[type]);
 }
 #if !defined(WIN32) && OPENSSL_VERSION_NUMBER < 0x10000000
 static unsigned long openssl_thread_id(void)
 {
     return (intptr_t) pthread_self();
 }
 #endif
 #endif

 int ff_openssl_init(void)
 {
     ff_lock_avformat();
     if (!openssl_init) {
         /* OpenSSL 1.0.2 or below, then you would use SSL_library_init. If you are
          * using OpenSSL 1.1.0 or above, then the library will initialize
          * itself automatically.
          * https://wiki.openssl.org/index.php/Library_Initialization
          */
 #if OPENSSL_VERSION_NUMBER < 0x10100000L
         SSL_library_init();
         SSL_load_error_strings();
 #endif
 #if HAVE_THREADS && OPENSSL_VERSION_NUMBER < 0x10100000L
         if (!CRYPTO_get_locking_callback()) {
             int i;
             openssl_mutexes = av_malloc_array(sizeof(pthread_mutex_t), CRYPTO_num_locks());
             if (!openssl_mutexes) {
                 ff_unlock_avformat();
                 return AVERROR(ENOMEM);
             }

             for (i = 0; i < CRYPTO_num_locks(); i++)
                 pthread_mutex_init(&openssl_mutexes[i], NULL);
             CRYPTO_set_locking_callback(openssl_lock);
 #if !defined(WIN32) && OPENSSL_VERSION_NUMBER < 0x10000000
             CRYPTO_set_id_callback(openssl_thread_id);
 #endif
         }
 #endif
     }
     openssl_init++;
     ff_unlock_avformat();

     return 0;
 }

 void ff_openssl_deinit(void)
 {
     ff_lock_avformat();
     openssl_init--;
     if (!openssl_init) {
 #if HAVE_THREADS && OPENSSL_VERSION_NUMBER < 0x10100000L
         if (CRYPTO_get_locking_callback() == openssl_lock) {
             int i;
             CRYPTO_set_locking_callback(NULL);
             for (i = 0; i < CRYPTO_num_locks(); i++)
                 pthread_mutex_destroy(&openssl_mutexes[i]);
             av_free(openssl_mutexes);
         }
 #endif
     }
     ff_unlock_avformat();
 }

 static int print_tls_error(URLContext *h, int ret)
 {
     TLSContext *c = h->priv_data;
     if (h->flags & AVIO_FLAG_NONBLOCK) {
         int err = SSL_get_error(c->ssl, ret);
         if (err == SSL_ERROR_WANT_READ || err == SSL_ERROR_WANT_WRITE)
             return AVERROR(EAGAIN);
     }
     av_log(h, AV_LOG_ERROR, "%s\n", ERR_error_string(ERR_get_error(), NULL));
     return AVERROR(EIO);
 }

 static int tls_close(URLContext *h)
 {
     TLSContext *c = h->priv_data;
     if (c->ssl) {
         SSL_shutdown(c->ssl);
         SSL_free(c->ssl);
     }
     if (c->ctx)
         SSL_CTX_free(c->ctx);
     if (c->tls_shared.tcp)
         ffurl_close(c->tls_shared.tcp);
 #if OPENSSL_VERSION_NUMBER >= 0x1010000fL
     if (c->url_bio_method)
         BIO_meth_free(c->url_bio_method);
 #endif
     ff_openssl_deinit();
     return 0;
 }

 static int url_bio_create(BIO *b)
 {
 #if OPENSSL_VERSION_NUMBER >= 0x1010000fL
     BIO_set_init(b, 1);
     BIO_set_data(b, NULL);
     BIO_set_flags(b, 0);
 #else
     b->init = 1;
     b->ptr = NULL;
     b->flags = 0;
 #endif
     return 1;
 }

 static int url_bio_destroy(BIO *b)
 {
     return 1;
 }

 #if OPENSSL_VERSION_NUMBER >= 0x1010000fL
 #define GET_BIO_DATA(x) BIO_get_data(x)
 #else
 #define GET_BIO_DATA(x) (x)->ptr
 #endif

 static int url_bio_bread(BIO *b, char *buf, int len)
 {
     URLContext *h = GET_BIO_DATA(b);
     int ret = ffurl_read(h, buf, len);
     if (ret >= 0)
         return ret;
     BIO_clear_retry_flags(b);
     if (ret == AVERROR(EAGAIN))
         BIO_set_retry_read(b);
     if (ret == AVERROR_EXIT)
         return 0;
     return -1;
 }

 static int url_bio_bwrite(BIO *b, const char *buf, int len)
 {
     URLContext *h = GET_BIO_DATA(b);
     int ret = ffurl_write(h, buf, len);
     if (ret >= 0)
         return ret;
     BIO_clear_retry_flags(b);
     if (ret == AVERROR(EAGAIN))
         BIO_set_retry_write(b);
     if (ret == AVERROR_EXIT)
         return 0;
     return -1;
 }

 static long url_bio_ctrl(BIO *b, int cmd, long num, void *ptr)
 {
     if (cmd == BIO_CTRL_FLUSH) {
         BIO_clear_retry_flags(b);
         return 1;
     }
     return 0;
 }

 static int url_bio_bputs(BIO *b, const char *str)
 {
     return url_bio_bwrite(b, str, strlen(str));
 }

 #if OPENSSL_VERSION_NUMBER < 0x1010000fL
 static BIO_METHOD url_bio_method = {
     .type = BIO_TYPE_SOURCE_SINK,
     .name = "urlprotocol bio",
     .bwrite = url_bio_bwrite,
     .bread = url_bio_bread,
     .bputs = url_bio_bputs,
     .bgets = NULL,
     .ctrl = url_bio_ctrl,
     .create = url_bio_create,
     .destroy = url_bio_destroy,
 };
 #endif

 static int tls_open(URLContext *h, const char *uri, int flags, AVDictionary **options)
 {
     TLSContext *p = h->priv_data;
     TLSShared *c = &p->tls_shared;
     BIO *bio;
     int ret;

     if ((ret = ff_openssl_init()) < 0)
         return ret;

     if ((ret = ff_tls_open_underlying(c, h, uri, options)) < 0)
         goto fail;

     // We want to support all versions of TLS >= 1.0, but not the deprecated
     // and insecure SSLv2 and SSLv3.  Despite the name, SSLv23_*_method()
     // enables support for all versions of SSL and TLS, and we then disable
     // support for the old protocols immediately after creating the context.
     p->ctx = SSL_CTX_new(c->listen ? SSLv23_server_method() : SSLv23_client_method());
     if (!p->ctx) {
         av_log(h, AV_LOG_ERROR, "%s\n", ERR_error_string(ERR_get_error(), NULL));
         ret = AVERROR(EIO);
         goto fail;
     }
     SSL_CTX_set_options(p->ctx, SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3);
     if (c->ca_file) {
         if (!SSL_CTX_load_verify_locations(p->ctx, c->ca_file, NULL))
             av_log(h, AV_LOG_ERROR, "SSL_CTX_load_verify_locations %s\n", ERR_error_string(ERR_get_error(), NULL));
     }
     if (c->cert_file && !SSL_CTX_use_certificate_chain_file(p->ctx, c->cert_file)) {
         av_log(h, AV_LOG_ERROR, "Unable to load cert file %s: %s\n",
                c->cert_file, ERR_error_string(ERR_get_error(), NULL));
         ret = AVERROR(EIO);
         goto fail;
     }
     if (c->key_file && !SSL_CTX_use_PrivateKey_file(p->ctx, c->key_file, SSL_FILETYPE_PEM)) {
         av_log(h, AV_LOG_ERROR, "Unable to load key file %s: %s\n",
                c->key_file, ERR_error_string(ERR_get_error(), NULL));
         ret = AVERROR(EIO);
         goto fail;
     }
     // Note, this doesn't check that the peer certificate actually matches
     // the requested hostname.
     if (c->verify)
         SSL_CTX_set_verify(p->ctx, SSL_VERIFY_PEER|SSL_VERIFY_FAIL_IF_NO_PEER_CERT, NULL);
     p->ssl = SSL_new(p->ctx);
     if (!p->ssl) {
         av_log(h, AV_LOG_ERROR, "%s\n", ERR_error_string(ERR_get_error(), NULL));
         ret = AVERROR(EIO);
         goto fail;
     }
 #if OPENSSL_VERSION_NUMBER >= 0x1010000fL
     p->url_bio_method = BIO_meth_new(BIO_TYPE_SOURCE_SINK, "urlprotocol bio");
     BIO_meth_set_write(p->url_bio_method, url_bio_bwrite);
     BIO_meth_set_read(p->url_bio_method, url_bio_bread);
     BIO_meth_set_puts(p->url_bio_method, url_bio_bputs);
     BIO_meth_set_ctrl(p->url_bio_method, url_bio_ctrl);
     BIO_meth_set_create(p->url_bio_method, url_bio_create);
     BIO_meth_set_destroy(p->url_bio_method, url_bio_destroy);
     bio = BIO_new(p->url_bio_method);
     BIO_set_data(bio, c->tcp);
 #else
     bio = BIO_new(&url_bio_method);
     bio->ptr = c->tcp;
 #endif
     SSL_set_bio(p->ssl, bio, bio);
     if (!c->listen && !c->numerichost)
         SSL_set_tlsext_host_name(p->ssl, c->host);
     ret = c->listen ? SSL_accept(p->ssl) : SSL_connect(p->ssl);
     if (ret == 0) {
         av_log(h, AV_LOG_ERROR, "Unable to negotiate TLS/SSL session\n");
         ret = AVERROR(EIO);
         goto fail;
     } else if (ret < 0) {
         ret = print_tls_error(h, ret);
         goto fail;
     }

     return 0;
 fail:
     tls_close(h);
     return ret;
 }

 static int tls_read(URLContext *h, uint8_t *buf, int size)
 {
     TLSContext *c = h->priv_data;
     int ret;
     // Set or clear the AVIO_FLAG_NONBLOCK on c->tls_shared.tcp
     c->tls_shared.tcp->flags &= ~AVIO_FLAG_NONBLOCK;
     c->tls_shared.tcp->flags |= h->flags & AVIO_FLAG_NONBLOCK;
     ret = SSL_read(c->ssl, buf, size);
     if (ret > 0)
         return ret;
     if (ret == 0)
         return AVERROR_EOF;
     return print_tls_error(h, ret);
 }

 static int tls_write(URLContext *h, const uint8_t *buf, int size)
 {
     TLSContext *c = h->priv_data;
     int ret;
     // Set or clear the AVIO_FLAG_NONBLOCK on c->tls_shared.tcp
     c->tls_shared.tcp->flags &= ~AVIO_FLAG_NONBLOCK;
     c->tls_shared.tcp->flags |= h->flags & AVIO_FLAG_NONBLOCK;
     ret = SSL_write(c->ssl, buf, size);
     if (ret > 0)
         return ret;
     if (ret == 0)
         return AVERROR_EOF;
     return print_tls_error(h, ret);
 }

 static int tls_get_file_handle(URLContext *h)
 {
     TLSContext *c = h->priv_data;
     return ffurl_get_file_handle(c->tls_shared.tcp);
 }

 static const AVOption options[] = {
     TLS_COMMON_OPTIONS(TLSContext, tls_shared),
     { NULL }
 };

 static const AVClass tls_class = {
     .class_name = "tls",
     .item_name  = av_default_item_name,
     .option     = options,
     .version    = LIBAVUTIL_VERSION_INT,
 };

 const URLProtocol ff_tls_protocol = {
     .name           = "tls",
     .url_open2      = tls_open,
     .url_read       = tls_read,
     .url_write      = tls_write,
     .url_close      = tls_close,
     .url_get_file_handle = tls_get_file_handle,
     .priv_data_size = sizeof(TLSContext),
     .flags          = URL_PROTOCOL_FLAG_NETWORK,
     .priv_data_class = &tls_class,
 };
	/*
	* TLS/SSL Protocol
	* Copyright (c) 2011 Martin Storsjo
	*
	* This file is part of FFmpeg.
	*
	* FFmpeg is free software; you can redistribute it and/or
	* modify it under the terms of the GNU Lesser General Public
	* License as published by the Free Software Foundation; either
	* version 2.1 of the License, or (at your option) any later version.
	*
	* FFmpeg is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	* Lesser General Public License for more details.
	*
	* You should have received a copy of the GNU Lesser General Public
	* License along with FFmpeg; if not, write to the Free Software
	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
	*/

	#include "avformat.h"
	#include "internal.h"
	#include "network.h"
	#include "os_support.h"
	#include "url.h"
	#include "tls.h"
	#include "libavcodec/internal.h"
	#include "libavutil/avstring.h"
	#include "libavutil/avutil.h"
	#include "libavutil/opt.h"
	#include "libavutil/parseutils.h"
	#include "libavutil/thread.h"

	#include <openssl/bio.h>
	#include <openssl/ssl.h>
	#include <openssl/err.h>

	static int openssl_init;

	typedef struct TLSContext {
	const AVClass *class;
	TLSShared tls_shared;
	SSL_CTX *ctx;
	SSL *ssl;
	#if OPENSSL_VERSION_NUMBER >= 0x1010000fL
	BIO_METHOD* url_bio_method;
	#endif
	} TLSContext;

	#if HAVE_THREADS && OPENSSL_VERSION_NUMBER < 0x10100000L
	#include <openssl/crypto.h>
	pthread_mutex_t *openssl_mutexes;
	static void openssl_lock(int mode, int type, const char *file, int line)
	{
	if (mode & CRYPTO_LOCK)
	pthread_mutex_lock(&openssl_mutexes[type]);
	else
	pthread_mutex_unlock(&openssl_mutexes[type]);
	}
	#if !defined(WIN32) && OPENSSL_VERSION_NUMBER < 0x10000000
	static unsigned long openssl_thread_id(void)
	{
	return (intptr_t) pthread_self();
	}
	#endif
	#endif

	int ff_openssl_init(void)
	{
	ff_lock_avformat();
	if (!openssl_init) {
	/* OpenSSL 1.0.2 or below, then you would use SSL_library_init. If you are
	* using OpenSSL 1.1.0 or above, then the library will initialize
	* itself automatically.
	* https://wiki.openssl.org/index.php/Library_Initialization
	*/
	#if OPENSSL_VERSION_NUMBER < 0x10100000L
	SSL_library_init();
	SSL_load_error_strings();
	#endif
	#if HAVE_THREADS && OPENSSL_VERSION_NUMBER < 0x10100000L
	if (!CRYPTO_get_locking_callback()) {
	int i;
	openssl_mutexes = av_malloc_array(sizeof(pthread_mutex_t), CRYPTO_num_locks());
	if (!openssl_mutexes) {
	ff_unlock_avformat();
	return AVERROR(ENOMEM);
	}

	for (i = 0; i < CRYPTO_num_locks(); i++)
	pthread_mutex_init(&openssl_mutexes[i], NULL);
	CRYPTO_set_locking_callback(openssl_lock);
	#if !defined(WIN32) && OPENSSL_VERSION_NUMBER < 0x10000000
	CRYPTO_set_id_callback(openssl_thread_id);
	#endif
	}
	#endif
	}
	openssl_init++;
	ff_unlock_avformat();

	return 0;
	}

	void ff_openssl_deinit(void)
	{
	ff_lock_avformat();
	openssl_init--;
	if (!openssl_init) {
	#if HAVE_THREADS && OPENSSL_VERSION_NUMBER < 0x10100000L
	if (CRYPTO_get_locking_callback() == openssl_lock) {
	int i;
	CRYPTO_set_locking_callback(NULL);
	for (i = 0; i < CRYPTO_num_locks(); i++)
	pthread_mutex_destroy(&openssl_mutexes[i]);
	av_free(openssl_mutexes);
	}
	#endif
	}
	ff_unlock_avformat();
	}

	static int print_tls_error(URLContext *h, int ret)
	{
	TLSContext *c = h->priv_data;
	if (h->flags & AVIO_FLAG_NONBLOCK) {
	int err = SSL_get_error(c->ssl, ret);
	if (err == SSL_ERROR_WANT_READ \|\| err == SSL_ERROR_WANT_WRITE)
	return AVERROR(EAGAIN);
	}
	av_log(h, AV_LOG_ERROR, "%s\n", ERR_error_string(ERR_get_error(), NULL));
	return AVERROR(EIO);
	}

	static int tls_close(URLContext *h)
	{
	TLSContext *c = h->priv_data;
	if (c->ssl) {
	SSL_shutdown(c->ssl);
	SSL_free(c->ssl);
	}
	if (c->ctx)
	SSL_CTX_free(c->ctx);
	if (c->tls_shared.tcp)
	ffurl_close(c->tls_shared.tcp);
	#if OPENSSL_VERSION_NUMBER >= 0x1010000fL
	if (c->url_bio_method)
	BIO_meth_free(c->url_bio_method);
	#endif
	ff_openssl_deinit();
	return 0;
	}

	static int url_bio_create(BIO *b)
	{
	#if OPENSSL_VERSION_NUMBER >= 0x1010000fL
	BIO_set_init(b, 1);
	BIO_set_data(b, NULL);
	BIO_set_flags(b, 0);
	#else
	b->init = 1;
	b->ptr = NULL;
	b->flags = 0;
	#endif
	return 1;
	}

	static int url_bio_destroy(BIO *b)
	{
	return 1;
	}

	#if OPENSSL_VERSION_NUMBER >= 0x1010000fL
	#define GET_BIO_DATA(x) BIO_get_data(x)
	#else
	#define GET_BIO_DATA(x) (x)->ptr
	#endif

	static int url_bio_bread(BIO b, char buf, int len)
	{
	URLContext *h = GET_BIO_DATA(b);
	int ret = ffurl_read(h, buf, len);
	if (ret >= 0)
	return ret;
	BIO_clear_retry_flags(b);
	if (ret == AVERROR(EAGAIN))
	BIO_set_retry_read(b);
	if (ret == AVERROR_EXIT)
	return 0;
	return -1;
	}

	static int url_bio_bwrite(BIO b, const char buf, int len)
	{
	URLContext *h = GET_BIO_DATA(b);
	int ret = ffurl_write(h, buf, len);
	if (ret >= 0)
	return ret;
	BIO_clear_retry_flags(b);
	if (ret == AVERROR(EAGAIN))
	BIO_set_retry_write(b);
	if (ret == AVERROR_EXIT)
	return 0;
	return -1;
	}

	static long url_bio_ctrl(BIO b, int cmd, long num, void ptr)
	{
	if (cmd == BIO_CTRL_FLUSH) {
	BIO_clear_retry_flags(b);
	return 1;
	}
	return 0;
	}

	static int url_bio_bputs(BIO b, const char str)
	{
	return url_bio_bwrite(b, str, strlen(str));
	}

	#if OPENSSL_VERSION_NUMBER < 0x1010000fL
	static BIO_METHOD url_bio_method = {
	.type = BIO_TYPE_SOURCE_SINK,
	.name = "urlprotocol bio",
	.bwrite = url_bio_bwrite,
	.bread = url_bio_bread,
	.bputs = url_bio_bputs,
	.bgets = NULL,
	.ctrl = url_bio_ctrl,
	.create = url_bio_create,
	.destroy = url_bio_destroy,
	};
	#endif

	static int tls_open(URLContext h, const char uri, int flags, AVDictionary **options)
	{
	TLSContext *p = h->priv_data;
	TLSShared *c = &p->tls_shared;
	BIO *bio;
	int ret;

	if ((ret = ff_openssl_init()) < 0)
	return ret;

	if ((ret = ff_tls_open_underlying(c, h, uri, options)) < 0)
	goto fail;

	// We want to support all versions of TLS >= 1.0, but not the deprecated
	// and insecure SSLv2 and SSLv3. Despite the name, SSLv23_*_method()
	// enables support for all versions of SSL and TLS, and we then disable
	// support for the old protocols immediately after creating the context.
	p->ctx = SSL_CTX_new(c->listen ? SSLv23_server_method() : SSLv23_client_method());
	if (!p->ctx) {
	av_log(h, AV_LOG_ERROR, "%s\n", ERR_error_string(ERR_get_error(), NULL));
	ret = AVERROR(EIO);
	goto fail;
	}
	SSL_CTX_set_options(p->ctx, SSL_OP_NO_SSLv2 \| SSL_OP_NO_SSLv3);
	if (c->ca_file) {
	if (!SSL_CTX_load_verify_locations(p->ctx, c->ca_file, NULL))
	av_log(h, AV_LOG_ERROR, "SSL_CTX_load_verify_locations %s\n", ERR_error_string(ERR_get_error(), NULL));
	}
	if (c->cert_file && !SSL_CTX_use_certificate_chain_file(p->ctx, c->cert_file)) {
	av_log(h, AV_LOG_ERROR, "Unable to load cert file %s: %s\n",
	c->cert_file, ERR_error_string(ERR_get_error(), NULL));
	ret = AVERROR(EIO);
	goto fail;
	}
	if (c->key_file && !SSL_CTX_use_PrivateKey_file(p->ctx, c->key_file, SSL_FILETYPE_PEM)) {
	av_log(h, AV_LOG_ERROR, "Unable to load key file %s: %s\n",
	c->key_file, ERR_error_string(ERR_get_error(), NULL));
	ret = AVERROR(EIO);
	goto fail;
	}
	// Note, this doesn't check that the peer certificate actually matches
	// the requested hostname.
	if (c->verify)
	SSL_CTX_set_verify(p->ctx, SSL_VERIFY_PEER\|SSL_VERIFY_FAIL_IF_NO_PEER_CERT, NULL);
	p->ssl = SSL_new(p->ctx);
	if (!p->ssl) {
	av_log(h, AV_LOG_ERROR, "%s\n", ERR_error_string(ERR_get_error(), NULL));
	ret = AVERROR(EIO);
	goto fail;
	}
	#if OPENSSL_VERSION_NUMBER >= 0x1010000fL
	p->url_bio_method = BIO_meth_new(BIO_TYPE_SOURCE_SINK, "urlprotocol bio");
	BIO_meth_set_write(p->url_bio_method, url_bio_bwrite);
	BIO_meth_set_read(p->url_bio_method, url_bio_bread);
	BIO_meth_set_puts(p->url_bio_method, url_bio_bputs);
	BIO_meth_set_ctrl(p->url_bio_method, url_bio_ctrl);
	BIO_meth_set_create(p->url_bio_method, url_bio_create);
	BIO_meth_set_destroy(p->url_bio_method, url_bio_destroy);
	bio = BIO_new(p->url_bio_method);
	BIO_set_data(bio, c->tcp);
	#else
	bio = BIO_new(&url_bio_method);
	bio->ptr = c->tcp;
	#endif
	SSL_set_bio(p->ssl, bio, bio);
	if (!c->listen && !c->numerichost)
	SSL_set_tlsext_host_name(p->ssl, c->host);
	ret = c->listen ? SSL_accept(p->ssl) : SSL_connect(p->ssl);
	if (ret == 0) {
	av_log(h, AV_LOG_ERROR, "Unable to negotiate TLS/SSL session\n");
	ret = AVERROR(EIO);
	goto fail;
	} else if (ret < 0) {
	ret = print_tls_error(h, ret);
	goto fail;
	}

	return 0;
	fail:
	tls_close(h);
	return ret;
	}

	static int tls_read(URLContext h, uint8_t buf, int size)
	{
	TLSContext *c = h->priv_data;
	int ret;
	// Set or clear the AVIO_FLAG_NONBLOCK on c->tls_shared.tcp
	c->tls_shared.tcp->flags &= ~AVIO_FLAG_NONBLOCK;
	c->tls_shared.tcp->flags \|= h->flags & AVIO_FLAG_NONBLOCK;
	ret = SSL_read(c->ssl, buf, size);
	if (ret > 0)
	return ret;
	if (ret == 0)
	return AVERROR_EOF;
	return print_tls_error(h, ret);
	}

	static int tls_write(URLContext h, const uint8_t buf, int size)
	{
	TLSContext *c = h->priv_data;
	int ret;
	// Set or clear the AVIO_FLAG_NONBLOCK on c->tls_shared.tcp
	c->tls_shared.tcp->flags &= ~AVIO_FLAG_NONBLOCK;
	c->tls_shared.tcp->flags \|= h->flags & AVIO_FLAG_NONBLOCK;
	ret = SSL_write(c->ssl, buf, size);
	if (ret > 0)
	return ret;
	if (ret == 0)
	return AVERROR_EOF;
	return print_tls_error(h, ret);
	}

	static int tls_get_file_handle(URLContext *h)
	{
	TLSContext *c = h->priv_data;
	return ffurl_get_file_handle(c->tls_shared.tcp);
	}

	static const AVOption options[] = {
	TLS_COMMON_OPTIONS(TLSContext, tls_shared),
	{ NULL }
	};

	static const AVClass tls_class = {
	.class_name = "tls",
	.item_name = av_default_item_name,
	.option = options,
	.version = LIBAVUTIL_VERSION_INT,
	};

	const URLProtocol ff_tls_protocol = {
	.name = "tls",
	.url_open2 = tls_open,
	.url_read = tls_read,
	.url_write = tls_write,
	.url_close = tls_close,
	.url_get_file_handle = tls_get_file_handle,
	.priv_data_size = sizeof(TLSContext),
	.flags = URL_PROTOCOL_FLAG_NETWORK,
	.priv_data_class = &tls_class,
	};