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authorMichael Niedermayer <michaelni@gmx.at>2012-07-23 21:04:06 +0200
committerMichael Niedermayer <michaelni@gmx.at>2012-07-23 21:25:09 +0200
commit2cb4d516549526b5e17e941f6d2375a2c501ade6 (patch)
treef472c62e0b34c2faaa955d51874cddb6be759910 /libavformat/rtmpdh.c
parent7e15df7551cf45ad1d3e39d20fdc8d6c651d4705 (diff)
parentd04c5293ce88927ad359ca276e287bfa63c2329d (diff)
downloadffmpeg-2cb4d516549526b5e17e941f6d2375a2c501ade6.tar.gz
Merge remote-tracking branch 'qatar/master'
* qatar/master: v410dec: Implement explode mode support zerocodec: fix direct rendering. wav: init st to NULL to avoid a false-positive warning. wavpack: set bits_per_raw_sample for S32 samples to properly identify 24-bit h264: refactor NAL decode loop RTMPTE protocol support RTMPE protocol support rtmp: Add ff_rtmp_calc_digest_pos() rtmp: Rename rtmp_calc_digest to ff_rtmp_calc_digest and make it global swscale: add missing HAVE_INLINE_ASM check. lavfi: place x86 inline assembly under HAVE_INLINE_ASM. vc1: Add a test for interlaced field pictures swscale: Mark all init functions as av_cold swscale: x86: Drop pointless _mmx suffix from filenames lavf: use conditional notation for default codec in muxer declarations. swscale: place inline assembly bilinear scaler under HAVE_INLINE_ASM. dsputil: ppc: cosmetics: pretty-print dsputil: x86: add SHUFFLE_MASK_W macro configure: respect CC_O setting in check_cc Conflicts: Changelog configure libavcodec/v410dec.c libavcodec/zerocodec.c libavformat/asfenc.c libavformat/version.h libswscale/utils.c libswscale/x86/swscale.c Merged-by: Michael Niedermayer <michaelni@gmx.at>
Diffstat (limited to 'libavformat/rtmpdh.c')
-rw-r--r--libavformat/rtmpdh.c329
1 files changed, 329 insertions, 0 deletions
diff --git a/libavformat/rtmpdh.c b/libavformat/rtmpdh.c
new file mode 100644
index 0000000000..fad87fca3b
--- /dev/null
+++ b/libavformat/rtmpdh.c
@@ -0,0 +1,329 @@
+/*
+ * RTMP Diffie-Hellmann utilities
+ * 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
+ * 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;
+}
+