diff --git a/Changelog b/Changelog index 3d1325414b..d51f5d3106 100644 --- a/Changelog +++ b/Changelog @@ -39,6 +39,7 @@ version : - RTMPTS protocol support - JPEG 2000 encoding support through OpenJPEG - G.723.1 demuxer and decoder +- RTMPE protocol support version 0.8: diff --git a/configure b/configure index f00eddd379..b862fd3f24 100755 --- a/configure +++ b/configure @@ -950,6 +950,7 @@ CONFIG_LIST=" fastdiv fft frei0r + gcrypt gnutls gpl gray @@ -982,6 +983,7 @@ CONFIG_LIST=" mdct memalign_hack mpegaudiodsp + nettle network nonfree openssl @@ -1543,6 +1545,9 @@ vfwcap_indev_extralibs="-lavicap32" x11_grab_device_indev_deps="x11grab XShmCreateImage" # protocols +ffrtmpcrypt_protocol_deps="!librtmp_protocol" +ffrtmpcrypt_protocol_deps_any="gcrypt nettle openssl" +ffrtmpcrypt_protocol_select="tcp_protocol" ffrtmphttp_protocol_deps="!librtmp_protocol" ffrtmphttp_protocol_select="http_protocol" gopher_protocol_deps="network" @@ -1560,6 +1565,7 @@ mmsh_protocol_select="http_protocol" mmst_protocol_deps="network" rtmp_protocol_deps="!librtmp_protocol" rtmp_protocol_select="tcp_protocol" +rtmpe_protocol_select="ffrtmpcrypt_protocol" rtmps_protocol_deps="!librtmp_protocol" rtmps_protocol_select="tls_protocol" rtmpt_protocol_select="ffrtmphttp_protocol" @@ -3014,6 +3020,11 @@ enabled openssl && { check_lib openssl/ssl.h SSL_library_init -lssl -lcrypto check_lib openssl/ssl.h SSL_library_init -lssl -lcrypto -lws2_32 -lgdi32 || die "ERROR: openssl not found"; } +if enabled gnutls; then + { check_lib nettle/bignum.h nettle_mpz_get_str_256 -lnettle -lhogweed -lgmp && enable nettle; } || + { check_lib gcrypt.h gcry_mpi_new -lgcrypt && enable gcrypt; } +fi + # libdc1394 check if enabled libdc1394; then { check_lib dc1394/dc1394.h dc1394_new -ldc1394 -lraw1394 && diff --git a/doc/general.texi b/doc/general.texi index f5c62936b7..c54ac00125 100644 --- a/doc/general.texi +++ b/doc/general.texi @@ -844,7 +844,7 @@ performance on systems without hardware floating point support). @item MMST @tab X @item pipe @tab X @item RTMP @tab X -@item RTMPE @tab E +@item RTMPE @tab X @item RTMPS @tab X @item RTMPT @tab X @item RTMPTE @tab E diff --git a/doc/protocols.texi b/doc/protocols.texi index aad7184126..fcb4da801e 100644 --- a/doc/protocols.texi +++ b/doc/protocols.texi @@ -247,6 +247,15 @@ For example to read with @command{avplay} a multimedia resource named avplay rtmp://myserver/vod/sample @end example +@section rtmpe + +Encrypted Real-Time Messaging Protocol. + +The Encrypted Real-Time Messaging Protocol (RTMPE) is used for +streaming multimedia content within standard cryptographic primitives, +consisting of Diffie-Hellman key exchange and HMACSHA256, generating +a pair of RC4 keys. + @section rtmps Real-Time Messaging Protocol over a secure SSL connection. diff --git a/libavformat/Makefile b/libavformat/Makefile index 43e42243bc..31a53345e7 100644 --- a/libavformat/Makefile +++ b/libavformat/Makefile @@ -341,6 +341,7 @@ OBJS-$(CONFIG_LIBRTMP) += librtmp.o OBJS-$(CONFIG_APPLEHTTP_PROTOCOL) += hlsproto.o OBJS-$(CONFIG_CONCAT_PROTOCOL) += concat.o OBJS-$(CONFIG_CRYPTO_PROTOCOL) += crypto.o +OBJS-$(CONFIG_FFRTMPCRYPT_PROTOCOL) += rtmpcrypt.o rtmpdh.o OBJS-$(CONFIG_FFRTMPHTTP_PROTOCOL) += rtmphttp.o OBJS-$(CONFIG_FILE_PROTOCOL) += file.o OBJS-$(CONFIG_GOPHER_PROTOCOL) += gopher.o @@ -353,6 +354,7 @@ OBJS-$(CONFIG_MMST_PROTOCOL) += mmst.o mms.o asf.o OBJS-$(CONFIG_MD5_PROTOCOL) += md5proto.o OBJS-$(CONFIG_PIPE_PROTOCOL) += file.o OBJS-$(CONFIG_RTMP_PROTOCOL) += rtmpproto.o rtmppkt.o +OBJS-$(CONFIG_RTMPE_PROTOCOL) += rtmpproto.o rtmppkt.o OBJS-$(CONFIG_RTMPS_PROTOCOL) += rtmpproto.o rtmppkt.o OBJS-$(CONFIG_RTMPT_PROTOCOL) += rtmpproto.o rtmppkt.o OBJS-$(CONFIG_RTMPTS_PROTOCOL) += rtmpproto.o rtmppkt.o diff --git a/libavformat/allformats.c b/libavformat/allformats.c index 34e9d610da..4e694b26fe 100644 --- a/libavformat/allformats.c +++ b/libavformat/allformats.c @@ -247,6 +247,7 @@ void av_register_all(void) #endif REGISTER_PROTOCOL (CONCAT, concat); REGISTER_PROTOCOL (CRYPTO, crypto); + REGISTER_PROTOCOL (FFRTMPCRYPT, ffrtmpcrypt); REGISTER_PROTOCOL (FFRTMPHTTP, ffrtmphttp); REGISTER_PROTOCOL (FILE, file); REGISTER_PROTOCOL (GOPHER, gopher); @@ -259,6 +260,7 @@ void av_register_all(void) REGISTER_PROTOCOL (MD5, md5); REGISTER_PROTOCOL (PIPE, pipe); REGISTER_PROTOCOL (RTMP, rtmp); + REGISTER_PROTOCOL (RTMPE, rtmpe); REGISTER_PROTOCOL (RTMPS, rtmps); REGISTER_PROTOCOL (RTMPT, rtmpt); REGISTER_PROTOCOL (RTMPTS, rtmpts); diff --git a/libavformat/rtmpcrypt.c b/libavformat/rtmpcrypt.c new file mode 100644 index 0000000000..e5afcc94ff --- /dev/null +++ b/libavformat/rtmpcrypt.c @@ -0,0 +1,309 @@ +/* + * RTMPE network protocol + * Copyright (c) 2012 Samuel Pitoiset + * + * This file is part of Libav. + * + * Libav 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. + * + * Libav 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 Libav; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +/** + * @file + * RTMPE protocol + */ + +#include "libavutil/blowfish.h" +#include "libavutil/intreadwrite.h" +#include "libavutil/rc4.h" +#include "libavutil/xtea.h" + +#include "internal.h" +#include "rtmp.h" +#include "rtmpdh.h" +#include "rtmpcrypt.h" +#include "url.h" + +/* protocol handler context */ +typedef struct RTMPEContext { + URLContext *stream; ///< TCP stream + FF_DH *dh; ///< Diffie-Hellman context + struct AVRC4 key_in; ///< RC4 key used for decrypt data + struct AVRC4 key_out; ///< RC4 key used for encrypt data + int handshaked; ///< flag indicating when the handshake is performed +} RTMPEContext; + +static const uint8_t rtmpe8_keys[16][16] = { + { 0xbf, 0xf0, 0x34, 0xb2, 0x11, 0xd9, 0x08, 0x1f, + 0xcc, 0xdf, 0xb7, 0x95, 0x74, 0x8d, 0xe7, 0x32 }, + { 0x08, 0x6a, 0x5e, 0xb6, 0x17, 0x43, 0x09, 0x0e, + 0x6e, 0xf0, 0x5a, 0xb8, 0xfe, 0x5a, 0x39, 0xe2 }, + { 0x7b, 0x10, 0x95, 0x6f, 0x76, 0xce, 0x05, 0x21, + 0x23, 0x88, 0xa7, 0x3a, 0x44, 0x01, 0x49, 0xa1 }, + { 0xa9, 0x43, 0xf3, 0x17, 0xeb, 0xf1, 0x1b, 0xb2, + 0xa6, 0x91, 0xa5, 0xee, 0x17, 0xf3, 0x63, 0x39 }, + { 0x7a, 0x30, 0xe0, 0x0a, 0xb5, 0x29, 0xe2, 0x2c, + 0xa0, 0x87, 0xae, 0xa5, 0xc0, 0xcb, 0x79, 0xac }, + { 0xbd, 0xce, 0x0c, 0x23, 0x2f, 0xeb, 0xde, 0xff, + 0x1c, 0xfa, 0xae, 0x16, 0x11, 0x23, 0x23, 0x9d }, + { 0x55, 0xdd, 0x3f, 0x7b, 0x77, 0xe7, 0xe6, 0x2e, + 0x9b, 0xb8, 0xc4, 0x99, 0xc9, 0x48, 0x1e, 0xe4 }, + { 0x40, 0x7b, 0xb6, 0xb4, 0x71, 0xe8, 0x91, 0x36, + 0xa7, 0xae, 0xbf, 0x55, 0xca, 0x33, 0xb8, 0x39 }, + { 0xfc, 0xf6, 0xbd, 0xc3, 0xb6, 0x3c, 0x36, 0x97, + 0x7c, 0xe4, 0xf8, 0x25, 0x04, 0xd9, 0x59, 0xb2 }, + { 0x28, 0xe0, 0x91, 0xfd, 0x41, 0x95, 0x4c, 0x4c, + 0x7f, 0xb7, 0xdb, 0x00, 0xe3, 0xa0, 0x66, 0xf8 }, + { 0x57, 0x84, 0x5b, 0x76, 0x4f, 0x25, 0x1b, 0x03, + 0x46, 0xd4, 0x5b, 0xcd, 0xa2, 0xc3, 0x0d, 0x29 }, + { 0x0a, 0xcc, 0xee, 0xf8, 0xda, 0x55, 0xb5, 0x46, + 0x03, 0x47, 0x34, 0x52, 0x58, 0x63, 0x71, 0x3b }, + { 0xb8, 0x20, 0x75, 0xdc, 0xa7, 0x5f, 0x1f, 0xee, + 0xd8, 0x42, 0x68, 0xe8, 0xa7, 0x2a, 0x44, 0xcc }, + { 0x07, 0xcf, 0x6e, 0x9e, 0xa1, 0x6d, 0x7b, 0x25, + 0x9f, 0xa7, 0xae, 0x6c, 0xd9, 0x2f, 0x56, 0x29 }, + { 0xfe, 0xb1, 0xea, 0xe4, 0x8c, 0x8c, 0x3c, 0xe1, + 0x4e, 0x00, 0x64, 0xa7, 0x6a, 0x38, 0x7c, 0x2a }, + { 0x89, 0x3a, 0x94, 0x27, 0xcc, 0x30, 0x13, 0xa2, + 0xf1, 0x06, 0x38, 0x5b, 0xa8, 0x29, 0xf9, 0x27 } +}; + +static const uint8_t rtmpe9_keys[16][24] = { + { 0x79, 0x34, 0x77, 0x4c, 0x67, 0xd1, 0x38, 0x3a, 0xdf, 0xb3, 0x56, 0xbe, + 0x8b, 0x7b, 0xd0, 0x24, 0x38, 0xe0, 0x73, 0x58, 0x41, 0x5d, 0x69, 0x67, }, + { 0x46, 0xf6, 0xb4, 0xcc, 0x01, 0x93, 0xe3, 0xa1, 0x9e, 0x7d, 0x3c, 0x65, + 0x55, 0x86, 0xfd, 0x09, 0x8f, 0xf7, 0xb3, 0xc4, 0x6f, 0x41, 0xca, 0x5c, }, + { 0x1a, 0xe7, 0xe2, 0xf3, 0xf9, 0x14, 0x79, 0x94, 0xc0, 0xd3, 0x97, 0x43, + 0x08, 0x7b, 0xb3, 0x84, 0x43, 0x2f, 0x9d, 0x84, 0x3f, 0x21, 0x01, 0x9b, }, + { 0xd3, 0xe3, 0x54, 0xb0, 0xf7, 0x1d, 0xf6, 0x2b, 0x5a, 0x43, 0x4d, 0x04, + 0x83, 0x64, 0x3e, 0x0d, 0x59, 0x2f, 0x61, 0xcb, 0xb1, 0x6a, 0x59, 0x0d, }, + { 0xc8, 0xc1, 0xe9, 0xb8, 0x16, 0x56, 0x99, 0x21, 0x7b, 0x5b, 0x36, 0xb7, + 0xb5, 0x9b, 0xdf, 0x06, 0x49, 0x2c, 0x97, 0xf5, 0x95, 0x48, 0x85, 0x7e, }, + { 0xeb, 0xe5, 0xe6, 0x2e, 0xa4, 0xba, 0xd4, 0x2c, 0xf2, 0x16, 0xe0, 0x8f, + 0x66, 0x23, 0xa9, 0x43, 0x41, 0xce, 0x38, 0x14, 0x84, 0x95, 0x00, 0x53, }, + { 0x66, 0xdb, 0x90, 0xf0, 0x3b, 0x4f, 0xf5, 0x6f, 0xe4, 0x9c, 0x20, 0x89, + 0x35, 0x5e, 0xd2, 0xb2, 0xc3, 0x9e, 0x9f, 0x7f, 0x63, 0xb2, 0x28, 0x81, }, + { 0xbb, 0x20, 0xac, 0xed, 0x2a, 0x04, 0x6a, 0x19, 0x94, 0x98, 0x9b, 0xc8, + 0xff, 0xcd, 0x93, 0xef, 0xc6, 0x0d, 0x56, 0xa7, 0xeb, 0x13, 0xd9, 0x30, }, + { 0xbc, 0xf2, 0x43, 0x82, 0x09, 0x40, 0x8a, 0x87, 0x25, 0x43, 0x6d, 0xe6, + 0xbb, 0xa4, 0xb9, 0x44, 0x58, 0x3f, 0x21, 0x7c, 0x99, 0xbb, 0x3f, 0x24, }, + { 0xec, 0x1a, 0xaa, 0xcd, 0xce, 0xbd, 0x53, 0x11, 0xd2, 0xfb, 0x83, 0xb6, + 0xc3, 0xba, 0xab, 0x4f, 0x62, 0x79, 0xe8, 0x65, 0xa9, 0x92, 0x28, 0x76, }, + { 0xc6, 0x0c, 0x30, 0x03, 0x91, 0x18, 0x2d, 0x7b, 0x79, 0xda, 0xe1, 0xd5, + 0x64, 0x77, 0x9a, 0x12, 0xc5, 0xb1, 0xd7, 0x91, 0x4f, 0x96, 0x4c, 0xa3, }, + { 0xd7, 0x7c, 0x2a, 0xbf, 0xa6, 0xe7, 0x85, 0x7c, 0x45, 0xad, 0xff, 0x12, + 0x94, 0xd8, 0xde, 0xa4, 0x5c, 0x3d, 0x79, 0xa4, 0x44, 0x02, 0x5d, 0x22, }, + { 0x16, 0x19, 0x0d, 0x81, 0x6a, 0x4c, 0xc7, 0xf8, 0xb8, 0xf9, 0x4e, 0xcd, + 0x2c, 0x9e, 0x90, 0x84, 0xb2, 0x08, 0x25, 0x60, 0xe1, 0x1e, 0xae, 0x18, }, + { 0xe9, 0x7c, 0x58, 0x26, 0x1b, 0x51, 0x9e, 0x49, 0x82, 0x60, 0x61, 0xfc, + 0xa0, 0xa0, 0x1b, 0xcd, 0xf5, 0x05, 0xd6, 0xa6, 0x6d, 0x07, 0x88, 0xa3, }, + { 0x2b, 0x97, 0x11, 0x8b, 0xd9, 0x4e, 0xd9, 0xdf, 0x20, 0xe3, 0x9c, 0x10, + 0xe6, 0xa1, 0x35, 0x21, 0x11, 0xf9, 0x13, 0x0d, 0x0b, 0x24, 0x65, 0xb2, }, + { 0x53, 0x6a, 0x4c, 0x54, 0xac, 0x8b, 0x9b, 0xb8, 0x97, 0x29, 0xfc, 0x60, + 0x2c, 0x5b, 0x3a, 0x85, 0x68, 0xb5, 0xaa, 0x6a, 0x44, 0xcd, 0x3f, 0xa7, }, +}; + +int ff_rtmpe_gen_pub_key(URLContext *h, uint8_t *buf) +{ + RTMPEContext *rt = h->priv_data; + int offset, ret; + + if (!(rt->dh = ff_dh_init(1024))) + return AVERROR(ENOMEM); + + offset = ff_rtmp_calc_digest_pos(buf, 768, 632, 8); + if (offset < 0) + return offset; + + /* generate a Diffie-Hellmann public key */ + if ((ret = ff_dh_generate_public_key(rt->dh)) < 0) + return ret; + + /* write the public key into the handshake buffer */ + if ((ret = ff_dh_write_public_key(rt->dh, buf + offset, 128)) < 0) + return ret; + + return 0; +} + +int ff_rtmpe_compute_secret_key(URLContext *h, const uint8_t *serverdata, + const uint8_t *clientdata, int type) +{ + RTMPEContext *rt = h->priv_data; + uint8_t secret_key[128], digest[32]; + int server_pos, client_pos; + int ret; + + if (type) { + if ((server_pos = ff_rtmp_calc_digest_pos(serverdata, 1532, 632, 772)) < 0) + return server_pos; + } else { + if ((server_pos = ff_rtmp_calc_digest_pos(serverdata, 768, 632, 8)) < 0) + return server_pos; + } + + if ((client_pos = ff_rtmp_calc_digest_pos(clientdata, 768, 632, 8)) < 0) + return client_pos; + + /* compute the shared secret secret in order to compute RC4 keys */ + if ((ret = ff_dh_compute_shared_secret_key(rt->dh, serverdata + server_pos, + 128, secret_key)) < 0) + return ret; + + /* set output key */ + if ((ret = ff_rtmp_calc_digest(serverdata + server_pos, 128, 0, secret_key, + 128, digest)) < 0) + return ret; + av_rc4_init(&rt->key_out, digest, 16 * 8, 1); + + /* set input key */ + if ((ret = ff_rtmp_calc_digest(clientdata + client_pos, 128, 0, secret_key, + 128, digest)) < 0) + return ret; + av_rc4_init(&rt->key_in, digest, 16 * 8, 1); + + return 0; +} + +static void rtmpe8_sig(const uint8_t *in, uint8_t *out, int key_id) +{ + struct AVXTEA ctx; + + av_xtea_init(&ctx, rtmpe8_keys[key_id]); + av_xtea_crypt(&ctx, out, in, 1, NULL, 0); +} + +static void rtmpe9_sig(const uint8_t *in, uint8_t *out, int key_id) +{ + struct AVBlowfish ctx; + uint32_t xl, xr; + + xl = AV_RL32(in); + xr = AV_RL32(in + 4); + + av_blowfish_init(&ctx, rtmpe9_keys[key_id], 24); + av_blowfish_crypt_ecb(&ctx, &xl, &xr, 0); + + AV_WL32(out, xl); + AV_WL32(out + 4, xr); +} + +void ff_rtmpe_encrypt_sig(URLContext *h, uint8_t *sig, const uint8_t *digest, + int type) +{ + int i; + + for (i = 0; i < 32; i += 8) { + if (type == 8) { + /* RTMPE type 8 uses XTEA on the signature */ + rtmpe8_sig(sig + i, sig + i, digest[i] % 15); + } else if (type == 9) { + /* RTMPE type 9 uses Blowfish on the signature */ + rtmpe9_sig(sig + i, sig + i, digest[i] % 15); + } + } +} + +int ff_rtmpe_update_keystream(URLContext *h) +{ + RTMPEContext *rt = h->priv_data; + char buf[RTMP_HANDSHAKE_PACKET_SIZE]; + + /* skip past 1536 bytes of the RC4 bytestream */ + av_rc4_crypt(&rt->key_in, buf, NULL, sizeof(buf), NULL, 1); + av_rc4_crypt(&rt->key_out, buf, NULL, sizeof(buf), NULL, 1); + + /* the next requests will be encrypted using RC4 keys */ + rt->handshaked = 1; + + return 0; +} + +static int rtmpe_close(URLContext *h) +{ + RTMPEContext *rt = h->priv_data; + + ff_dh_free(rt->dh); + ffurl_close(rt->stream); + + return 0; +} + +static int rtmpe_open(URLContext *h, const char *uri, int flags) +{ + RTMPEContext *rt = h->priv_data; + char host[256], url[1024]; + int ret, port; + + av_url_split(NULL, 0, NULL, 0, host, sizeof(host), &port, NULL, 0, uri); + + if (port < 0) + port = 1935; + + /* open the tcp connection */ + ff_url_join(url, sizeof(url), "tcp", NULL, host, port, NULL); + if ((ret = ffurl_open(&rt->stream, url, AVIO_FLAG_READ_WRITE, + &h->interrupt_callback, NULL)) < 0) { + rtmpe_close(h); + return ret; + } + + return 0; +} + +static int rtmpe_read(URLContext *h, uint8_t *buf, int size) +{ + RTMPEContext *rt = h->priv_data; + int ret; + + rt->stream->flags |= h->flags & AVIO_FLAG_NONBLOCK; + ret = ffurl_read(rt->stream, buf, size); + rt->stream->flags &= ~AVIO_FLAG_NONBLOCK; + + if (ret < 0 && ret != AVERROR_EOF) + return ret; + + if (rt->handshaked && ret > 0) { + /* decrypt data received by the server */ + av_rc4_crypt(&rt->key_in, buf, buf, ret, NULL, 1); + } + + return ret; +} + +static int rtmpe_write(URLContext *h, const uint8_t *buf, int size) +{ + RTMPEContext *rt = h->priv_data; + int ret; + + if (rt->handshaked) { + /* encrypt data to send to the server */ + av_rc4_crypt(&rt->key_out, buf, buf, size, NULL, 1); + } + + if ((ret = ffurl_write(rt->stream, buf, size)) < 0) + return ret; + + return size; +} + +URLProtocol ff_ffrtmpcrypt_protocol = { + .name = "ffrtmpcrypt", + .url_open = rtmpe_open, + .url_read = rtmpe_read, + .url_write = rtmpe_write, + .url_close = rtmpe_close, + .priv_data_size = sizeof(RTMPEContext), + .flags = URL_PROTOCOL_FLAG_NETWORK, +}; diff --git a/libavformat/rtmpcrypt.h b/libavformat/rtmpcrypt.h new file mode 100644 index 0000000000..27994333df --- /dev/null +++ b/libavformat/rtmpcrypt.h @@ -0,0 +1,69 @@ +/* + * RTMPE encryption utilities + * Copyright (c) 2012 Samuel Pitoiset + * + * This file is part of Libav. + * + * Libav 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. + * + * Libav 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 Libav; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#ifndef AVFORMAT_RTMPCRYPT_H +#define AVFORMAT_RTMPCRYPT_H + +#include + +#include "url.h" + +/** + * Initialize the Diffie-Hellmann context and generate the public key. + * + * @param h an URLContext + * @param buf handshake data (1536 bytes) + * @return zero on success, negative value otherwise + */ +int ff_rtmpe_gen_pub_key(URLContext *h, uint8_t *buf); + +/** + * Compute the shared secret key and initialize the RC4 encryption. + * + * @param h an URLContext + * @param serverdata server data (1536 bytes) + * @param clientdata client data (1536 bytes) + * @param type the position of the server digest + * @return zero on success, negative value otherwise + */ +int ff_rtmpe_compute_secret_key(URLContext *h, const uint8_t *serverdata, + const uint8_t *clientdata, int type); + +/** + * Encrypt the signature. + * + * @param h an URLContext + * @param signature the signature to encrypt + * @param digest the digest used for finding the encryption key + * @param type type of encryption (8 for XTEA, 9 for Blowfish) + */ +void ff_rtmpe_encrypt_sig(URLContext *h, uint8_t *signature, + const uint8_t *digest, int type); + +/** + * Update the keystream and set RC4 keys for encryption. + * + * @param h an URLContext + * @return zero on success, negative value otherwise + */ +int ff_rtmpe_update_keystream(URLContext *h); + +#endif /* AVFORMAT_RTMPCRYPT_H */ diff --git a/libavformat/rtmpdh.c b/libavformat/rtmpdh.c new file mode 100644 index 0000000000..8ddc5fcee8 --- /dev/null +++ b/libavformat/rtmpdh.c @@ -0,0 +1,329 @@ +/* + * RTMP Diffie-Hellmann utilities + * Copyright (c) 2012 Samuel Pitoiset + * + * This file is part of Libav. + * + * Libav 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. + * + * Libav 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 Libav; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +/** + * @file + * RTMP Diffie-Hellmann utilities + */ + +#include "config.h" +#include "rtmpdh.h" + +#define P1024 \ + "FFFFFFFFFFFFFFFFC90FDAA22168C234C4C6628B80DC1CD1" \ + "29024E088A67CC74020BBEA63B139B22514A08798E3404DD" \ + "EF9519B3CD3A431B302B0A6DF25F14374FE1356D6D51C245" \ + "E485B576625E7EC6F44C42E9A637ED6B0BFF5CB6F406B7ED" \ + "EE386BFB5A899FA5AE9F24117C4B1FE649286651ECE65381" \ + "FFFFFFFFFFFFFFFF" + +#define Q1024 \ + "7FFFFFFFFFFFFFFFE487ED5110B4611A62633145C06E0E68" \ + "948127044533E63A0105DF531D89CD9128A5043CC71A026E" \ + "F7CA8CD9E69D218D98158536F92F8A1BA7F09AB6B6A8E122" \ + "F242DABB312F3F637A262174D31BF6B585FFAE5B7A035BF6" \ + "F71C35FDAD44CFD2D74F9208BE258FF324943328F67329C0" \ + "FFFFFFFFFFFFFFFF" + +#if CONFIG_NETTLE || CONFIG_GCRYPT +#if CONFIG_NETTLE +#define bn_new(bn) \ + do { \ + bn = av_malloc(sizeof(*bn)); \ + if (bn) \ + mpz_init2(bn, 1); \ + } while (0) +#define bn_free(bn) \ + do { \ + mpz_clear(bn); \ + av_free(bn); \ + } while (0) +#define bn_set_word(bn, w) mpz_set_ui(bn, w) +#define bn_cmp(a, b) mpz_cmp(a, b) +#define bn_copy(to, from) mpz_set(to, from) +#define bn_sub_word(bn, w) mpz_sub_ui(bn, bn, w) +#define bn_cmp_1(bn) mpz_cmp_ui(bn, 1) +#define bn_num_bytes(bn) (mpz_sizeinbase(bn, 2) + 7) / 8 +#define bn_bn2bin(bn, buf, len) nettle_mpz_get_str_256(len, buf, bn) +#define bn_bin2bn(bn, buf, len) \ + do { \ + bn_new(bn); \ + if (bn) \ + nettle_mpz_set_str_256_u(bn, len, buf); \ + } while (0) +#define bn_hex2bn(bn, buf, ret) \ + do { \ + bn_new(bn); \ + if (bn) \ + ret = (mpz_set_str(bn, buf, 16) == 0); \ + } while (0) +#define bn_modexp(bn, y, q, p) mpz_powm(bn, y, q, p) +#define bn_random(bn, num_bytes) mpz_random(bn, num_bytes); +#elif CONFIG_GCRYPT +#define bn_new(bn) bn = gcry_mpi_new(1) +#define bn_free(bn) gcry_mpi_release(bn) +#define bn_set_word(bn, w) gcry_mpi_set_ui(bn, w) +#define bn_cmp(a, b) gcry_mpi_cmp(a, b) +#define bn_copy(to, from) gcry_mpi_set(to, from) +#define bn_sub_word(bn, w) gcry_mpi_sub_ui(bn, bn, w) +#define bn_cmp_1(bn) gcry_mpi_cmp_ui(bn, 1) +#define bn_num_bytes(bn) (gcry_mpi_get_nbits(bn) + 7) / 8 +#define bn_bn2bin(bn, buf, len) gcry_mpi_print(GCRYMPI_FMT_USG, buf, len, NULL, bn) +#define bn_bin2bn(bn, buf, len) gcry_mpi_scan(&bn, GCRYMPI_FMT_USG, buf, len, NULL) +#define bn_hex2bn(bn, buf, ret) ret = (gcry_mpi_scan(&bn, GCRYMPI_FMT_HEX, buf, 0, 0) == 0) +#define bn_modexp(bn, y, q, p) gcry_mpi_powm(bn, y, q, p) +#define bn_random(bn, num_bytes) gcry_mpi_randomize(bn, num_bytes, GCRY_WEAK_RANDOM) +#endif + +#define MAX_BYTES 18000 + +#define dh_new() av_malloc(sizeof(FF_DH)) + +static FFBigNum dh_generate_key(FF_DH *dh) +{ + int num_bytes; + + num_bytes = bn_num_bytes(dh->p) - 1; + if (num_bytes <= 0 || num_bytes > MAX_BYTES) + return NULL; + + bn_new(dh->priv_key); + if (!dh->priv_key) + return NULL; + bn_random(dh->priv_key, num_bytes); + + bn_new(dh->pub_key); + if (!dh->pub_key) { + bn_free(dh->priv_key); + return NULL; + } + + bn_modexp(dh->pub_key, dh->g, dh->priv_key, dh->p); + + return dh->pub_key; +} + +static int dh_compute_key(FF_DH *dh, FFBigNum pub_key_bn, + uint32_t pub_key_len, uint8_t *secret_key) +{ + FFBigNum k; + int num_bytes; + + num_bytes = bn_num_bytes(dh->p); + if (num_bytes <= 0 || num_bytes > MAX_BYTES) + return -1; + + bn_new(k); + if (!k) + return -1; + + bn_modexp(k, pub_key_bn, dh->priv_key, dh->p); + bn_bn2bin(k, secret_key, pub_key_len); + bn_free(k); + + /* return the length of the shared secret key like DH_compute_key */ + return pub_key_len; +} + +void ff_dh_free(FF_DH *dh) +{ + bn_free(dh->p); + bn_free(dh->g); + bn_free(dh->pub_key); + bn_free(dh->priv_key); + av_free(dh); +} +#elif CONFIG_OPENSSL +#define bn_new(bn) bn = BN_new() +#define bn_free(bn) BN_free(bn) +#define bn_set_word(bn, w) BN_set_word(bn, w) +#define bn_cmp(a, b) BN_cmp(a, b) +#define bn_copy(to, from) BN_copy(to, from) +#define bn_sub_word(bn, w) BN_sub_word(bn, w) +#define bn_cmp_1(bn) BN_cmp(bn, BN_value_one()) +#define bn_num_bytes(bn) BN_num_bytes(bn) +#define bn_bn2bin(bn, buf, len) BN_bn2bin(bn, buf) +#define bn_bin2bn(bn, buf, len) bn = BN_bin2bn(buf, len, 0) +#define bn_hex2bn(bn, buf, ret) ret = BN_hex2bn(&bn, buf) +#define bn_modexp(bn, y, q, p) \ + do { \ + BN_CTX *ctx = BN_CTX_new(); \ + if (!ctx) \ + return AVERROR(ENOMEM); \ + if (!BN_mod_exp(bn, y, q, p, ctx)) { \ + BN_CTX_free(ctx); \ + return AVERROR(EINVAL); \ + } \ + BN_CTX_free(ctx); \ + } while (0) + +#define dh_new() DH_new() +#define dh_generate_key(dh) DH_generate_key(dh) +#define dh_compute_key(dh, pub, len, secret) DH_compute_key(secret, pub, dh) + +void ff_dh_free(FF_DH *dh) +{ + DH_free(dh); +} +#endif + +static int dh_is_valid_public_key(FFBigNum y, FFBigNum p, FFBigNum q) +{ + FFBigNum bn = NULL; + int ret = AVERROR(EINVAL); + + bn_new(bn); + if (!bn) + return AVERROR(ENOMEM); + + /* y must lie in [2, p - 1] */ + bn_set_word(bn, 1); + if (!bn_cmp(y, bn)) + goto fail; + + /* bn = p - 2 */ + bn_copy(bn, p); + bn_sub_word(bn, 1); + if (!bn_cmp(y, bn)) + goto fail; + + /* Verify with Sophie-Germain prime + * + * This is a nice test to make sure the public key position is calculated + * correctly. This test will fail in about 50% of the cases if applied to + * random data. + */ + /* y must fulfill y^q mod p = 1 */ + bn_modexp(bn, y, q, p); + + if (bn_cmp_1(bn)) + goto fail; + + ret = 0; +fail: + bn_free(bn); + + return ret; +} + +av_cold FF_DH *ff_dh_init(int key_len) +{ + FF_DH *dh; + int ret; + + if (!(dh = dh_new())) + return NULL; + + bn_new(dh->g); + if (!dh->g) + goto fail; + + bn_hex2bn(dh->p, P1024, ret); + if (!ret) + goto fail; + + bn_set_word(dh->g, 2); + dh->length = key_len; + + return dh; + +fail: + ff_dh_free(dh); + + return NULL; +} + +int ff_dh_generate_public_key(FF_DH *dh) +{ + int ret = 0; + + while (!ret) { + FFBigNum q1 = NULL; + + if (!dh_generate_key(dh)) + return AVERROR(EINVAL); + + bn_hex2bn(q1, Q1024, ret); + if (!ret) + return AVERROR(ENOMEM); + + ret = dh_is_valid_public_key(dh->pub_key, dh->p, q1); + bn_free(q1); + + if (!ret) { + /* the public key is valid */ + break; + } + } + + return ret; +} + +int ff_dh_write_public_key(FF_DH *dh, uint8_t *pub_key, int pub_key_len) +{ + int len; + + /* compute the length of the public key */ + len = bn_num_bytes(dh->pub_key); + if (len <= 0 || len > pub_key_len) + return AVERROR(EINVAL); + + /* convert the public key value into big-endian form */ + memset(pub_key, 0, pub_key_len); + bn_bn2bin(dh->pub_key, pub_key + pub_key_len - len, len); + + return 0; +} + +int ff_dh_compute_shared_secret_key(FF_DH *dh, const uint8_t *pub_key, + int pub_key_len, uint8_t *secret_key) +{ + FFBigNum q1 = NULL, pub_key_bn = NULL; + int ret; + + /* convert the big-endian form of the public key into a bignum */ + bn_bin2bn(pub_key_bn, pub_key, pub_key_len); + if (!pub_key_bn) + return AVERROR(ENOMEM); + + /* convert the string containing a hexadecimal number into a bignum */ + bn_hex2bn(q1, Q1024, ret); + if (!ret) { + ret = AVERROR(ENOMEM); + goto fail; + } + + /* when the public key is valid we have to compute the shared secret key */ + if ((ret = dh_is_valid_public_key(pub_key_bn, dh->p, q1)) < 0) { + goto fail; + } else if ((ret = dh_compute_key(dh, pub_key_bn, pub_key_len, + secret_key)) < 0) { + ret = AVERROR(EINVAL); + goto fail; + } + +fail: + bn_free(pub_key_bn); + bn_free(q1); + + return ret; +} + diff --git a/libavformat/rtmpdh.h b/libavformat/rtmpdh.h new file mode 100644 index 0000000000..5de8bde821 --- /dev/null +++ b/libavformat/rtmpdh.h @@ -0,0 +1,102 @@ +/* + * RTMP Diffie-Hellmann utilities + * Copyright (c) 2012 Samuel Pitoiset + * + * This file is part of Libav. + * + * Libav 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. + * + * Libav 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 Libav; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#ifndef AVFORMAT_RTMPDH_H +#define AVFORMAT_RTMPDH_H + +#include "avformat.h" +#include "config.h" + +#if CONFIG_NETTLE || CONFIG_GCRYPT +#if CONFIG_NETTLE +#include +#include + +typedef mpz_ptr FFBigNum; +#elif CONFIG_GCRYPT +#include + +typedef gcry_mpi_t FFBigNum; +#endif + +typedef struct FF_DH { + FFBigNum p; + FFBigNum g; + FFBigNum pub_key; + FFBigNum priv_key; + long length; +} FF_DH; + +#elif CONFIG_OPENSSL +#include +#include + +typedef BIGNUM *FFBigNum; +typedef DH FF_DH; +#endif + +/** + * Initialize a Diffie-Hellmann context. + * + * @param key_len length of the key + * @return a new Diffie-Hellmann context on success, NULL otherwise + */ +FF_DH *ff_dh_init(int key_len); + +/** + * Free a Diffie-Hellmann context. + * + * @param dh a Diffie-Hellmann context to free + */ +void ff_dh_free(FF_DH *dh); + +/** + * Generate a public key. + * + * @param dh a Diffie-Hellmann context + * @return zero on success, negative value otherwise + */ +int ff_dh_generate_public_key(FF_DH *dh); + +/** + * Write the public key into the given buffer. + * + * @param dh a Diffie-Hellmann context, containing the public key to write + * @param pub_key the buffer where the public key is written + * @param pub_key_len the length of the buffer + * @return zero on success, negative value otherwise + */ +int ff_dh_write_public_key(FF_DH *dh, uint8_t *pub_key, int pub_key_len); + +/** + * Compute the shared secret key from the private FF_DH value and the + * other party's public value. + * + * @param dh a Diffie-Hellmann context, containing the private key + * @param pub_key the buffer containing the public key + * @param pub_key_len the length of the buffer + * @param secret_key the buffer where the secret key is written + * @return length of the shared secret key on success, negative value otherwise + */ +int ff_dh_compute_shared_secret_key(FF_DH *dh, const uint8_t *pub_key, + int pub_key_len, uint8_t *secret_key); + +#endif /* AVFORMAT_RTMPDH_H */ diff --git a/libavformat/rtmpproto.c b/libavformat/rtmpproto.c index 64704502e9..67a89c5c82 100644 --- a/libavformat/rtmpproto.c +++ b/libavformat/rtmpproto.c @@ -37,6 +37,7 @@ #include "flv.h" #include "rtmp.h" +#include "rtmpcrypt.h" #include "rtmppkt.h" #include "url.h" @@ -92,6 +93,7 @@ typedef struct RTMPContext { int server_bw; ///< server bandwidth int client_buffer_time; ///< client buffer time in ms int flush_interval; ///< number of packets flushed in the same request (RTMPT only) + int encrypted; ///< use an encrypted connection (RTMPE only) } RTMPContext; #define PLAYER_KEY_OPEN_PART_LEN 30 ///< length of partial key used for first client digest signing @@ -649,13 +651,17 @@ int ff_rtmp_calc_digest_pos(const uint8_t *buf, int off, int mod_val, * will be stored) into that packet. * * @param buf handshake data (1536 bytes) + * @param encrypted use an encrypted connection (RTMPE) * @return offset to the digest inside input data */ -static int rtmp_handshake_imprint_with_digest(uint8_t *buf) +static int rtmp_handshake_imprint_with_digest(uint8_t *buf, int encrypted) { int ret, digest_pos; - digest_pos = ff_rtmp_calc_digest_pos(buf, 8, 728, 12); + if (encrypted) + digest_pos = ff_rtmp_calc_digest_pos(buf, 772, 728, 776); + else + digest_pos = ff_rtmp_calc_digest_pos(buf, 8, 728, 12); ret = ff_rtmp_calc_digest(buf, RTMP_HANDSHAKE_PACKET_SIZE, digest_pos, rtmp_player_key, PLAYER_KEY_OPEN_PART_LEN, @@ -712,8 +718,9 @@ static int rtmp_handshake(URLContext *s, RTMPContext *rt) uint8_t serverdata[RTMP_HANDSHAKE_PACKET_SIZE+1]; int i; int server_pos, client_pos; - uint8_t digest[32]; - int ret; + uint8_t digest[32], signature[32]; + int encrypted = rt->encrypted && CONFIG_FFRTMPCRYPT_PROTOCOL; + int ret, type = 0; av_log(s, AV_LOG_DEBUG, "Handshaking...\n"); @@ -721,7 +728,24 @@ static int rtmp_handshake(URLContext *s, RTMPContext *rt) // generate handshake packet - 1536 bytes of pseudorandom data for (i = 9; i <= RTMP_HANDSHAKE_PACKET_SIZE; i++) tosend[i] = av_lfg_get(&rnd) >> 24; - client_pos = rtmp_handshake_imprint_with_digest(tosend + 1); + + if (encrypted) { + /* When the client wants to use RTMPE, we have to change the command + * byte to 0x06 which means to use encrypted data and we have to set + * the flash version to at least 9.0.115.0. */ + tosend[0] = 6; + tosend[5] = 128; + tosend[6] = 0; + tosend[7] = 3; + tosend[8] = 2; + + /* Initialize the Diffie-Hellmann context and generate the public key + * to send to the server. */ + if ((ret = ff_rtmpe_gen_pub_key(rt->stream, tosend + 1)) < 0) + return ret; + } + + client_pos = rtmp_handshake_imprint_with_digest(tosend + 1, encrypted); if (client_pos < 0) return client_pos; @@ -743,6 +767,7 @@ static int rtmp_handshake(URLContext *s, RTMPContext *rt) return ret; } + av_log(s, AV_LOG_DEBUG, "Type answer %d\n", serverdata[0]); av_log(s, AV_LOG_DEBUG, "Server version %d.%d.%d.%d\n", serverdata[5], serverdata[6], serverdata[7], serverdata[8]); @@ -752,6 +777,7 @@ static int rtmp_handshake(URLContext *s, RTMPContext *rt) return server_pos; if (!server_pos) { + type = 1; server_pos = rtmp_validate_digest(serverdata + 1, 8); if (server_pos < 0) return server_pos; @@ -769,11 +795,22 @@ static int rtmp_handshake(URLContext *s, RTMPContext *rt) return ret; ret = ff_rtmp_calc_digest(clientdata, RTMP_HANDSHAKE_PACKET_SIZE - 32, - 0, digest, 32, digest); + 0, digest, 32, signature); if (ret < 0) return ret; - if (memcmp(digest, clientdata + RTMP_HANDSHAKE_PACKET_SIZE - 32, 32)) { + if (encrypted) { + /* Compute the shared secret key sent by the server and initialize + * the RC4 encryption. */ + if ((ret = ff_rtmpe_compute_secret_key(rt->stream, serverdata + 1, + tosend + 1, type)) < 0) + return ret; + + /* Encrypt the signature received by the server. */ + ff_rtmpe_encrypt_sig(rt->stream, signature, digest, serverdata[0]); + } + + if (memcmp(signature, clientdata + RTMP_HANDSHAKE_PACKET_SIZE - 32, 32)) { av_log(s, AV_LOG_ERROR, "Signature mismatch\n"); return AVERROR(EIO); } @@ -792,14 +829,47 @@ static int rtmp_handshake(URLContext *s, RTMPContext *rt) if (ret < 0) return ret; + if (encrypted) { + /* Encrypt the signature to be send to the server. */ + ff_rtmpe_encrypt_sig(rt->stream, tosend + + RTMP_HANDSHAKE_PACKET_SIZE - 32, digest, + serverdata[0]); + } + // write reply back to the server if ((ret = ffurl_write(rt->stream, tosend, RTMP_HANDSHAKE_PACKET_SIZE)) < 0) return ret; + + if (encrypted) { + /* Set RC4 keys for encryption and update the keystreams. */ + if ((ret = ff_rtmpe_update_keystream(rt->stream)) < 0) + return ret; + } } else { + if (encrypted) { + /* Compute the shared secret key sent by the server and initialize + * the RC4 encryption. */ + if ((ret = ff_rtmpe_compute_secret_key(rt->stream, serverdata + 1, + tosend + 1, 1)) < 0) + return ret; + + if (serverdata[0] == 9) { + /* Encrypt the signature received by the server. */ + ff_rtmpe_encrypt_sig(rt->stream, signature, digest, + serverdata[0]); + } + } + if ((ret = ffurl_write(rt->stream, serverdata + 1, RTMP_HANDSHAKE_PACKET_SIZE)) < 0) return ret; + + if (encrypted) { + /* Set RC4 keys for encryption and update the keystreams. */ + if ((ret = ff_rtmpe_update_keystream(rt->stream)) < 0) + return ret; + } } return 0; @@ -1122,6 +1192,10 @@ static int rtmp_open(URLContext *s, const char *uri, int flags) if (port < 0) port = RTMPS_DEFAULT_PORT; ff_url_join(buf, sizeof(buf), "tls", NULL, hostname, port, NULL); + } else if (!strcmp(proto, "rtmpe")) { + /* open the encrypted connection */ + ff_url_join(buf, sizeof(buf), "ffrtmpcrypt", NULL, hostname, port, NULL); + rt->encrypted = 1; } else { /* open the tcp connection */ if (port < 0) @@ -1446,6 +1520,24 @@ URLProtocol ff_rtmp_protocol = { .priv_data_class= &rtmp_class, }; +static const AVClass rtmpe_class = { + .class_name = "rtmpe", + .item_name = av_default_item_name, + .option = rtmp_options, + .version = LIBAVUTIL_VERSION_INT, +}; + +URLProtocol ff_rtmpe_protocol = { + .name = "rtmpe", + .url_open = rtmp_open, + .url_read = rtmp_read, + .url_write = rtmp_write, + .url_close = rtmp_close, + .priv_data_size = sizeof(RTMPContext), + .flags = URL_PROTOCOL_FLAG_NETWORK, + .priv_data_class = &rtmpe_class, +}; + static const AVClass rtmps_class = { .class_name = "rtmps", .item_name = av_default_item_name, diff --git a/libavformat/version.h b/libavformat/version.h index d20b07005a..3681e8db13 100644 --- a/libavformat/version.h +++ b/libavformat/version.h @@ -30,7 +30,7 @@ #include "libavutil/avutil.h" #define LIBAVFORMAT_VERSION_MAJOR 54 -#define LIBAVFORMAT_VERSION_MINOR 10 +#define LIBAVFORMAT_VERSION_MINOR 11 #define LIBAVFORMAT_VERSION_MICRO 0 #define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \