RTMPE protocol support

This adds two protocols, but one of them is an internal implementation
detail just used as an abstraction layer/generalization in the code. The
RTMPE protocol implementation uses ffrtmpcrypt:// as an alternative to the
tcp:// protocol. This allows moving most of the lower level logic out
from the higher level generic rtmp code.

Signed-off-by: Martin Storsjö <martin@martin.st>
This commit is contained in:
Samuel Pitoiset 2012-07-19 14:13:58 +02:00 committed by Martin Storsjö
parent 0e31088b6c
commit acd554c103
12 changed files with 935 additions and 9 deletions

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@ -39,6 +39,7 @@ version <next>:
- RTMPTS protocol support
- JPEG 2000 encoding support through OpenJPEG
- G.723.1 demuxer and decoder
- RTMPE protocol support
version 0.8:

11
configure vendored
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@ -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 &&

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@ -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

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@ -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.

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@ -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

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@ -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);

309
libavformat/rtmpcrypt.c Normal file
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@ -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,
};

69
libavformat/rtmpcrypt.h Normal file
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@ -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 <stdint.h>
#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 */

329
libavformat/rtmpdh.c Normal file
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@ -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;
}

102
libavformat/rtmpdh.h Normal file
View File

@ -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 <gmp.h>
#include <nettle/bignum.h>
typedef mpz_ptr FFBigNum;
#elif CONFIG_GCRYPT
#include <gcrypt.h>
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 <openssl/bn.h>
#include <openssl/dh.h>
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 */

View File

@ -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,

View File

@ -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, \