| /* |
| * RTMPE network protocol |
| * Copyright (c) 2008-2009 Andrej Stepanchuk |
| * Copyright (c) 2009-2010 Howard Chu |
| * Copyright (c) 2012 Samuel Pitoiset |
| * |
| * 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 |
| */ |
| |
| /** |
| * @file |
| * RTMPE protocol |
| */ |
| |
| #include "libavutil/blowfish.h" |
| #include "libavutil/intreadwrite.h" |
| #include "libavutil/opt.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 { |
| const AVClass *class; |
| 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 |
| int tunneling; ///< use a HTTP connection (RTMPTE) |
| } RTMPEContext; |
| |
| static const uint8_t rtmpe8_keys[16][16] = { |
| { 0xb2, 0x34, 0xf0, 0xbf, 0x1f, 0x08, 0xd9, 0x11, |
| 0x95, 0xb7, 0xdf, 0xcc, 0x32, 0xe7, 0x8d, 0x74 }, |
| { 0xb6, 0x5e, 0x6a, 0x08, 0x0e, 0x09, 0x43, 0x17, |
| 0xb8, 0x5a, 0xf0, 0x6e, 0xe2, 0x39, 0x5a, 0xfe }, |
| { 0x6f, 0x95, 0x10, 0x7b, 0x21, 0x05, 0xce, 0x76, |
| 0x3a, 0xa7, 0x88, 0x23, 0xa1, 0x49, 0x01, 0x44 }, |
| { 0x17, 0xf3, 0x43, 0xa9, 0xb2, 0x1b, 0xf1, 0xeb, |
| 0xee, 0xa5, 0x91, 0xa6, 0x39, 0x63, 0xf3, 0x17 }, |
| { 0x0a, 0xe0, 0x30, 0x7a, 0x2c, 0xe2, 0x29, 0xb5, |
| 0xa5, 0xae, 0x87, 0xa0, 0xac, 0x79, 0xcb, 0xc0 }, |
| { 0x23, 0x0c, 0xce, 0xbd, 0xff, 0xde, 0xeb, 0x2f, |
| 0x16, 0xae, 0xfa, 0x1c, 0x9d, 0x23, 0x23, 0x11 }, |
| { 0x7b, 0x3f, 0xdd, 0x55, 0x2e, 0xe6, 0xe7, 0x77, |
| 0x99, 0xc4, 0xb8, 0x9b, 0xe4, 0x1e, 0x48, 0xc9 }, |
| { 0xb4, 0xb6, 0x7b, 0x40, 0x36, 0x91, 0xe8, 0x71, |
| 0x55, 0xbf, 0xae, 0xa7, 0x39, 0xb8, 0x33, 0xca }, |
| { 0xc3, 0xbd, 0xf6, 0xfc, 0x97, 0x36, 0x3c, 0xb6, |
| 0x25, 0xf8, 0xe4, 0x7c, 0xb2, 0x59, 0xd9, 0x04 }, |
| { 0xfd, 0x91, 0xe0, 0x28, 0x4c, 0x4c, 0x95, 0x41, |
| 0x00, 0xdb, 0xb7, 0x7f, 0xf8, 0x66, 0xa0, 0xe3 }, |
| { 0x76, 0x5b, 0x84, 0x57, 0x03, 0x1b, 0x25, 0x4f, |
| 0xcd, 0x5b, 0xd4, 0x46, 0x29, 0x0d, 0xc3, 0xa2 }, |
| { 0xf8, 0xee, 0xcc, 0x0a, 0x46, 0xb5, 0x55, 0xda, |
| 0x52, 0x34, 0x47, 0x03, 0x3b, 0x71, 0x63, 0x58 }, |
| { 0xdc, 0x75, 0x20, 0xb8, 0xee, 0x1f, 0x5f, 0xa7, |
| 0xe8, 0x68, 0x42, 0xd8, 0xcc, 0x44, 0x2a, 0xa7 }, |
| { 0x9e, 0x6e, 0xcf, 0x07, 0x25, 0x7b, 0x6d, 0xa1, |
| 0x6c, 0xae, 0xa7, 0x9f, 0x29, 0x56, 0x2f, 0xd9 }, |
| { 0xe4, 0xea, 0xb1, 0xfe, 0xe1, 0x3c, 0x8c, 0x8c, |
| 0xa7, 0x64, 0x00, 0x4e, 0x2a, 0x7c, 0x38, 0x6a }, |
| { 0x27, 0x94, 0x3a, 0x89, 0xa2, 0x13, 0x30, 0xcc, |
| 0x5b, 0x38, 0x06, 0xf1, 0x27, 0xf9, 0x29, 0xa8 } |
| }; |
| |
| 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, sizeof(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_le_init(&ctx, rtmpe8_keys[key_id]); |
| av_xtea_le_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 (rt->tunneling) { |
| if (port < 0) |
| port = 80; |
| ff_url_join(url, sizeof(url), "ffrtmphttp", NULL, host, port, NULL); |
| } else { |
| if (port < 0) |
| port = 1935; |
| ff_url_join(url, sizeof(url), "tcp", NULL, host, port, NULL); |
| } |
| |
| /* open the tcp or ffrtmphttp connection */ |
| if ((ret = ffurl_open_whitelist(&rt->stream, url, AVIO_FLAG_READ_WRITE, |
| &h->interrupt_callback, NULL, |
| h->protocol_whitelist)) < 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; |
| } |
| |
| #define OFFSET(x) offsetof(RTMPEContext, x) |
| #define DEC AV_OPT_FLAG_DECODING_PARAM |
| |
| static const AVOption ffrtmpcrypt_options[] = { |
| {"ffrtmpcrypt_tunneling", "Use a HTTP tunneling connection (RTMPTE).", OFFSET(tunneling), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1, DEC}, |
| { NULL }, |
| }; |
| |
| static const AVClass ffrtmpcrypt_class = { |
| .class_name = "ffrtmpcrypt", |
| .item_name = av_default_item_name, |
| .option = ffrtmpcrypt_options, |
| .version = LIBAVUTIL_VERSION_INT, |
| }; |
| |
| 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, |
| .priv_data_class = &ffrtmpcrypt_class, |
| }; |