diff options
| -rw-r--r-- | doc/protocols.texi | 33 | ||||
| -rw-r--r-- | libavformat/tls.c | 68 | ||||
| -rw-r--r-- | libavformat/version.h | 2 |
3 files changed, 101 insertions, 2 deletions
diff --git a/doc/protocols.texi b/doc/protocols.texi index 1c7de475f4..2c618b8e0e 100644 --- a/doc/protocols.texi +++ b/doc/protocols.texi @@ -568,6 +568,39 @@ avplay tcp://@var{hostname}:@var{port} @end table +@section tls + +Transport Layer Security (TLS) / Secure Sockets Layer (SSL) + +The required syntax for a TLS url is: +@example +tls://@var{hostname}:@var{port} +@end example + +The following parameters can be set via command line options +(or in code via @code{AVOption}s): + +@table @option + +@item ca_file +A file containing certificate authority (CA) root certificates to treat +as trusted. If the linked TLS library contains a default this might not +need to be specified for verification to work, but not all libraries and +setups have defaults built in. + +@item tls_verify=@var{1|0} +If enabled, try to verify the peer that we are communicating with. +Note, if using OpenSSL, this currently only makes sure that the +peer certificate is signed by one of the root certificates in the CA +database, but it does not validate that the certificate actually +matches the host name we are trying to connect to. (With GnuTLS, +the host name is validated as well.) + +This is disabled by default since it requires a CA database to be +provided by the caller in many cases. + +@end table + @section udp User Datagram Protocol. diff --git a/libavformat/tls.c b/libavformat/tls.c index 7fa6fc2cae..4f475e069c 100644 --- a/libavformat/tls.c +++ b/libavformat/tls.c @@ -22,8 +22,10 @@ #include "avformat.h" #include "url.h" #include "libavutil/avstring.h" +#include "libavutil/opt.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) @@ -65,8 +67,26 @@ typedef struct { SSL *ssl; #endif int fd; + char *ca_file; + int verify; } 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 }, + {"tls_verify", "Verify the peer certificate", OFFSET(verify), 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; @@ -158,7 +178,14 @@ static int tls_open(URLContext *h, const char *uri, int flags) if (!numerichost) gnutls_server_name_set(c->session, GNUTLS_NAME_DNS, host, strlen(host)); gnutls_certificate_allocate_credentials(&c->cred); - gnutls_certificate_set_verify_flags(c->cred, 0); + if (c->ca_file) + gnutls_certificate_set_x509_trust_file(c->cred, c->ca_file, GNUTLS_X509_FMT_PEM); +#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); gnutls_credentials_set(c->session, GNUTLS_CRD_CERTIFICATE, c->cred); gnutls_transport_set_ptr(c->session, (gnutls_transport_ptr_t) (intptr_t) c->fd); @@ -170,6 +197,38 @@ static int tls_open(URLContext *h, const char *uri, int flags) 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(TLSv1_client_method()); if (!c->ctx) { @@ -177,6 +236,12 @@ static int tls_open(URLContext *h, const char *uri, int flags) ret = AVERROR(EIO); goto fail; } + if (c->ca_file) + SSL_CTX_load_verify_locations(c->ctx, c->ca_file, NULL); + // 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, 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)); @@ -256,4 +321,5 @@ URLProtocol ff_tls_protocol = { .url_close = tls_close, .priv_data_size = sizeof(TLSContext), .flags = URL_PROTOCOL_FLAG_NETWORK, + .priv_data_class = &tls_class, }; diff --git a/libavformat/version.h b/libavformat/version.h index 6d8bd52f62..66ca26403a 100644 --- a/libavformat/version.h +++ b/libavformat/version.h @@ -31,7 +31,7 @@ #define LIBAVFORMAT_VERSION_MAJOR 55 #define LIBAVFORMAT_VERSION_MINOR 5 -#define LIBAVFORMAT_VERSION_MICRO 1 +#define LIBAVFORMAT_VERSION_MICRO 2 #define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \ LIBAVFORMAT_VERSION_MINOR, \ |