ffmpeg/libavformat/tls.c

406 lines
13 KiB
C

/*
* 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 "url.h"
#include "libavutil/avstring.h"
#include "libavutil/opt.h"
#include "libavutil/parseutils.h"
#include "network.h"
#include "os_support.h"
#include "internal.h"
#if CONFIG_GNUTLS
#include <gnutls/gnutls.h>
#include <gnutls/x509.h>
#define TLS_read(c, buf, size) gnutls_record_recv((c)->session, (buf), (size))
#define TLS_write(c, buf, size) gnutls_record_send((c)->session, (buf), (size))
#define TLS_shutdown(c) gnutls_bye((c)->session, GNUTLS_SHUT_RDWR)
#define TLS_free(c) do { \
if ((c)->session) \
gnutls_deinit((c)->session); \
if ((c)->cred) \
gnutls_certificate_free_credentials((c)->cred); \
} while (0)
#elif CONFIG_OPENSSL
#include <openssl/bio.h>
#include <openssl/ssl.h>
#include <openssl/err.h>
#define TLS_read(c, buf, size) SSL_read((c)->ssl, (buf), (size))
#define TLS_write(c, buf, size) SSL_write((c)->ssl, (buf), (size))
#define TLS_shutdown(c) SSL_shutdown((c)->ssl)
#define TLS_free(c) do { \
if ((c)->ssl) \
SSL_free((c)->ssl); \
if ((c)->ctx) \
SSL_CTX_free((c)->ctx); \
} while (0)
#endif
#if HAVE_POLL_H
#include <poll.h>
#endif
typedef struct TLSContext {
const AVClass *class;
URLContext *tcp;
#if CONFIG_GNUTLS
gnutls_session_t session;
gnutls_certificate_credentials_t cred;
#elif CONFIG_OPENSSL
SSL_CTX *ctx;
SSL *ssl;
#endif
int fd;
char *ca_file;
int verify;
char *cert_file;
char *key_file;
int listen;
} TLSContext;
#define OFFSET(x) offsetof(TLSContext, x)
#define D AV_OPT_FLAG_DECODING_PARAM
#define E AV_OPT_FLAG_ENCODING_PARAM
static const AVOption options[] = {
{"ca_file", "Certificate Authority database file", OFFSET(ca_file), AV_OPT_TYPE_STRING, .flags = D|E },
{"cafile", "Certificate Authority database file", OFFSET(ca_file), AV_OPT_TYPE_STRING, .flags = D|E },
{"tls_verify", "Verify the peer certificate", OFFSET(verify), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, .flags = D|E },
{"cert_file", "Certificate file", OFFSET(cert_file), AV_OPT_TYPE_STRING, .flags = D|E },
{"key_file", "Private key file", OFFSET(key_file), AV_OPT_TYPE_STRING, .flags = D|E },
{"listen", "Listen for incoming connections", OFFSET(listen), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, .flags = D|E },
{ NULL }
};
static const AVClass tls_class = {
.class_name = "tls",
.item_name = av_default_item_name,
.option = options,
.version = LIBAVUTIL_VERSION_INT,
};
static int do_tls_poll(URLContext *h, int ret)
{
TLSContext *c = h->priv_data;
struct pollfd p = { c->fd, 0, 0 };
#if CONFIG_GNUTLS
switch (ret) {
case GNUTLS_E_AGAIN:
case GNUTLS_E_INTERRUPTED:
break;
case GNUTLS_E_WARNING_ALERT_RECEIVED:
av_log(h, AV_LOG_WARNING, "%s\n", gnutls_strerror(ret));
break;
default:
av_log(h, AV_LOG_ERROR, "%s\n", gnutls_strerror(ret));
return AVERROR(EIO);
}
if (gnutls_record_get_direction(c->session))
p.events = POLLOUT;
else
p.events = POLLIN;
#elif CONFIG_OPENSSL
ret = SSL_get_error(c->ssl, ret);
if (ret == SSL_ERROR_WANT_READ) {
p.events = POLLIN;
} else if (ret == SSL_ERROR_WANT_WRITE) {
p.events = POLLOUT;
} else {
av_log(h, AV_LOG_ERROR, "%s\n", ERR_error_string(ERR_get_error(), NULL));
return AVERROR(EIO);
}
#endif
if (h->flags & AVIO_FLAG_NONBLOCK)
return AVERROR(EAGAIN);
while (1) {
int n = poll(&p, 1, 100);
if (n > 0)
break;
if (ff_check_interrupt(&h->interrupt_callback))
return AVERROR(EINTR);
}
return 0;
}
static void set_options(URLContext *h, const char *uri)
{
TLSContext *c = h->priv_data;
char buf[1024];
const char *p = strchr(uri, '?');
if (!p)
return;
if (!c->ca_file && av_find_info_tag(buf, sizeof(buf), "cafile", p))
c->ca_file = av_strdup(buf);
if (!c->verify && av_find_info_tag(buf, sizeof(buf), "verify", p)) {
char *endptr = NULL;
c->verify = strtol(buf, &endptr, 10);
if (buf == endptr)
c->verify = 1;
}
if (!c->cert_file && av_find_info_tag(buf, sizeof(buf), "cert", p))
c->cert_file = av_strdup(buf);
if (!c->key_file && av_find_info_tag(buf, sizeof(buf), "key", p))
c->key_file = av_strdup(buf);
}
static int tls_open(URLContext *h, const char *uri, int flags, AVDictionary **options)
{
TLSContext *c = h->priv_data;
int ret;
int port;
const char *p;
char buf[200], host[200], opts[50] = "";
int numerichost = 0;
struct addrinfo hints = { 0 }, *ai = NULL;
const char *proxy_path;
int use_proxy;
if ((ret = ff_tls_init()) < 0)
return ret;
if (c->listen)
snprintf(opts, sizeof(opts), "?listen=1");
av_url_split(NULL, 0, NULL, 0, host, sizeof(host), &port, NULL, 0, uri);
p = strchr(uri, '?');
if (!p) {
p = opts;
} else {
if (av_find_info_tag(opts, sizeof(opts), "listen", p))
c->listen = 1;
}
ff_url_join(buf, sizeof(buf), "tcp", NULL, host, port, "%s", p);
hints.ai_flags = AI_NUMERICHOST;
if (!getaddrinfo(host, NULL, &hints, &ai)) {
numerichost = 1;
freeaddrinfo(ai);
}
proxy_path = getenv("http_proxy");
use_proxy = !ff_http_match_no_proxy(getenv("no_proxy"), host) &&
proxy_path && av_strstart(proxy_path, "http://", NULL);
if (use_proxy) {
char proxy_host[200], proxy_auth[200], dest[200];
int proxy_port;
av_url_split(NULL, 0, proxy_auth, sizeof(proxy_auth),
proxy_host, sizeof(proxy_host), &proxy_port, NULL, 0,
proxy_path);
ff_url_join(dest, sizeof(dest), NULL, NULL, host, port, NULL);
ff_url_join(buf, sizeof(buf), "httpproxy", proxy_auth, proxy_host,
proxy_port, "/%s", dest);
}
ret = ffurl_open(&c->tcp, buf, AVIO_FLAG_READ_WRITE,
&h->interrupt_callback, options);
if (ret)
goto fail;
c->fd = ffurl_get_file_handle(c->tcp);
#if CONFIG_GNUTLS
gnutls_init(&c->session, c->listen ? GNUTLS_SERVER : GNUTLS_CLIENT);
if (!c->listen && !numerichost)
gnutls_server_name_set(c->session, GNUTLS_NAME_DNS, host, strlen(host));
gnutls_certificate_allocate_credentials(&c->cred);
set_options(h, uri);
if (c->ca_file) {
ret = gnutls_certificate_set_x509_trust_file(c->cred, c->ca_file, GNUTLS_X509_FMT_PEM);
if (ret < 0)
av_log(h, AV_LOG_ERROR, "%s\n", gnutls_strerror(ret));
}
#if GNUTLS_VERSION_MAJOR >= 3
else
gnutls_certificate_set_x509_system_trust(c->cred);
#endif
gnutls_certificate_set_verify_flags(c->cred, c->verify ?
GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT : 0);
if (c->cert_file && c->key_file) {
ret = gnutls_certificate_set_x509_key_file(c->cred,
c->cert_file, c->key_file,
GNUTLS_X509_FMT_PEM);
if (ret < 0) {
av_log(h, AV_LOG_ERROR,
"Unable to set cert/key files %s and %s: %s\n",
c->cert_file, c->key_file, gnutls_strerror(ret));
ret = AVERROR(EIO);
goto fail;
}
} else if (c->cert_file || c->key_file)
av_log(h, AV_LOG_ERROR, "cert and key required\n");
gnutls_credentials_set(c->session, GNUTLS_CRD_CERTIFICATE, c->cred);
gnutls_transport_set_ptr(c->session, (gnutls_transport_ptr_t)
(intptr_t) c->fd);
gnutls_priority_set_direct(c->session, "NORMAL", NULL);
while (1) {
ret = gnutls_handshake(c->session);
if (ret == 0)
break;
if ((ret = do_tls_poll(h, ret)) < 0)
goto fail;
}
if (c->verify) {
unsigned int status, cert_list_size;
gnutls_x509_crt_t cert;
const gnutls_datum_t *cert_list;
if ((ret = gnutls_certificate_verify_peers2(c->session, &status)) < 0) {
av_log(h, AV_LOG_ERROR, "Unable to verify peer certificate: %s\n",
gnutls_strerror(ret));
ret = AVERROR(EIO);
goto fail;
}
if (status & GNUTLS_CERT_INVALID) {
av_log(h, AV_LOG_ERROR, "Peer certificate failed verification\n");
ret = AVERROR(EIO);
goto fail;
}
if (gnutls_certificate_type_get(c->session) != GNUTLS_CRT_X509) {
av_log(h, AV_LOG_ERROR, "Unsupported certificate type\n");
ret = AVERROR(EIO);
goto fail;
}
gnutls_x509_crt_init(&cert);
cert_list = gnutls_certificate_get_peers(c->session, &cert_list_size);
gnutls_x509_crt_import(cert, cert_list, GNUTLS_X509_FMT_DER);
ret = gnutls_x509_crt_check_hostname(cert, host);
gnutls_x509_crt_deinit(cert);
if (!ret) {
av_log(h, AV_LOG_ERROR,
"The certificate's owner does not match hostname %s\n", host);
ret = AVERROR(EIO);
goto fail;
}
}
#elif CONFIG_OPENSSL
c->ctx = SSL_CTX_new(c->listen ? TLSv1_server_method() : TLSv1_client_method());
if (!c->ctx) {
av_log(h, AV_LOG_ERROR, "%s\n", ERR_error_string(ERR_get_error(), NULL));
ret = AVERROR(EIO);
goto fail;
}
set_options(h, uri);
if (c->ca_file) {
if (!SSL_CTX_load_verify_locations(c->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(c->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(c->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(c->ctx, SSL_VERIFY_PEER|SSL_VERIFY_FAIL_IF_NO_PEER_CERT, NULL);
c->ssl = SSL_new(c->ctx);
if (!c->ssl) {
av_log(h, AV_LOG_ERROR, "%s\n", ERR_error_string(ERR_get_error(), NULL));
ret = AVERROR(EIO);
goto fail;
}
SSL_set_fd(c->ssl, c->fd);
if (!c->listen && !numerichost)
SSL_set_tlsext_host_name(c->ssl, host);
while (1) {
ret = c->listen ? SSL_accept(c->ssl) : SSL_connect(c->ssl);
if (ret > 0)
break;
if (ret == 0) {
av_log(h, AV_LOG_ERROR, "Unable to negotiate TLS/SSL session\n");
ret = AVERROR(EIO);
goto fail;
}
if ((ret = do_tls_poll(h, ret)) < 0)
goto fail;
}
#endif
return 0;
fail:
TLS_free(c);
if (c->tcp)
ffurl_close(c->tcp);
ff_tls_deinit();
return ret;
}
static int tls_read(URLContext *h, uint8_t *buf, int size)
{
TLSContext *c = h->priv_data;
while (1) {
int ret = TLS_read(c, buf, size);
if (ret > 0)
return ret;
if (ret == 0)
return AVERROR_EOF;
if ((ret = do_tls_poll(h, ret)) < 0)
return ret;
}
return 0;
}
static int tls_write(URLContext *h, const uint8_t *buf, int size)
{
TLSContext *c = h->priv_data;
while (1) {
int ret = TLS_write(c, buf, size);
if (ret > 0)
return ret;
if (ret == 0)
return AVERROR_EOF;
if ((ret = do_tls_poll(h, ret)) < 0)
return ret;
}
return 0;
}
static int tls_close(URLContext *h)
{
TLSContext *c = h->priv_data;
TLS_shutdown(c);
TLS_free(c);
ffurl_close(c->tcp);
ff_tls_deinit();
return 0;
}
URLProtocol ff_tls_protocol = {
.name = "tls",
.url_open2 = tls_open,
.url_read = tls_read,
.url_write = tls_write,
.url_close = tls_close,
.priv_data_size = sizeof(TLSContext),
.flags = URL_PROTOCOL_FLAG_NETWORK,
.priv_data_class = &tls_class,
};