diff --git a/doc/protocols.texi b/doc/protocols.texi index d2bdf23bab..e53d6a47a5 100644 --- a/doc/protocols.texi +++ b/doc/protocols.texi @@ -853,30 +853,45 @@ ffplay tcp://@var{hostname}:@var{port} @section tls -Transport Layer Security/Secure Sockets Layer +Transport Layer Security (TLS) / Secure Sockets Layer (SSL) The required syntax for a TLS/SSL url is: @example tls://@var{hostname}:@var{port}[?@var{options}] @end example +The following parameters can be set via command line options +(or in code via @code{AVOption}s): + @table @option +@item ca_file, cafile=@var{filename} +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. +The file must be in OpenSSL PEM format. + +@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. + @item listen Act as a server, listening for an incoming connection. -@item cafile=@var{filename} -Certificate authority file. The file must be in OpenSSL PEM format. - @item cert=@var{filename} Certificate file. The file must be in OpenSSL PEM format. @item key=@var{filename} Private key file. -@item verify=@var{0|1} -Verify the peer's certificate. - @end table Example command lines: diff --git a/libavformat/tls.c b/libavformat/tls.c index 4bf70a9ff6..6031b266a2 100644 --- a/libavformat/tls.c +++ b/libavformat/tls.c @@ -22,9 +22,11 @@ #include "avformat.h" #include "url.h" #include "libavutil/avstring.h" +#include "libavutil/opt.h" #include "libavutil/parseutils.h" #if CONFIG_GNUTLS #include +#include #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) @@ -66,8 +68,27 @@ 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 }, + {"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 }, + { 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; @@ -115,7 +136,7 @@ static void set_options(URLContext *h, const char *uri) { TLSContext *c = h->priv_data; char buf[1024], key[1024]; - int has_cert, has_key, verify = 0; + int has_cert, has_key; #if CONFIG_GNUTLS int ret; #endif @@ -123,22 +144,14 @@ static void set_options(URLContext *h, const char *uri) if (!p) return; - if (av_find_info_tag(buf, sizeof(buf), "cafile", p)) { -#if CONFIG_GNUTLS - ret = gnutls_certificate_set_x509_trust_file(c->cred, buf, GNUTLS_X509_FMT_PEM); - if (ret < 0) - av_log(h, AV_LOG_ERROR, "%s\n", gnutls_strerror(ret)); -#elif CONFIG_OPENSSL - if (!SSL_CTX_load_verify_locations(c->ctx, buf, NULL)) - av_log(h, AV_LOG_ERROR, "SSL_CTX_load_verify_locations %s\n", ERR_error_string(ERR_get_error(), NULL)); -#endif - } + if (!c->ca_file && av_find_info_tag(buf, sizeof(buf), "cafile", p)) + c->ca_file = av_strdup(buf); - if (av_find_info_tag(buf, sizeof(buf), "verify", p)) { + if (!c->verify && av_find_info_tag(buf, sizeof(buf), "verify", p)) { char *endptr = NULL; - verify = strtol(buf, &endptr, 10); + c->verify = strtol(buf, &endptr, 10); if (buf == endptr) - verify = 1; + c->verify = 1; } has_cert = av_find_info_tag(buf, sizeof(buf), "cert", p); @@ -151,14 +164,11 @@ static void set_options(URLContext *h, const char *uri) } else if (has_cert ^ has_key) { av_log(h, AV_LOG_ERROR, "cert and key required\n"); } - gnutls_certificate_set_verify_flags(c->cred, verify); #elif CONFIG_OPENSSL if (has_cert && !SSL_CTX_use_certificate_chain_file(c->ctx, buf)) av_log(h, AV_LOG_ERROR, "SSL_CTX_use_certificate_chain_file %s\n", ERR_error_string(ERR_get_error(), NULL)); if (has_key && !SSL_CTX_use_PrivateKey_file(c->ctx, key, SSL_FILETYPE_PEM)) av_log(h, AV_LOG_ERROR, "SSL_CTX_use_PrivateKey_file %s\n", ERR_error_string(ERR_get_error(), NULL)); - if (verify) - SSL_CTX_set_verify(c->ctx, SSL_VERIFY_PEER|SSL_VERIFY_FAIL_IF_NO_PEER_CERT, 0); #endif } @@ -215,6 +225,17 @@ static int tls_open(URLContext *h, const char *uri, int flags) 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); gnutls_credentials_set(c->session, GNUTLS_CRD_CERTIFICATE, c->cred); gnutls_transport_set_ptr(c->session, (gnutls_transport_ptr_t) (intptr_t) c->fd); @@ -226,6 +247,38 @@ 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(server ? TLSv1_server_method() : TLSv1_client_method()); if (!c->ctx) { @@ -234,6 +287,14 @@ static int tls_open(URLContext *h, const char *uri, int flags) 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)); + } + // 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)); @@ -313,4 +374,5 @@ 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 c2242329c4..a601072138 100644 --- a/libavformat/version.h +++ b/libavformat/version.h @@ -31,7 +31,7 @@ #define LIBAVFORMAT_VERSION_MAJOR 55 #define LIBAVFORMAT_VERSION_MINOR 18 -#define LIBAVFORMAT_VERSION_MICRO 102 +#define LIBAVFORMAT_VERSION_MICRO 103 #define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \ LIBAVFORMAT_VERSION_MINOR, \