diff --git a/doc/APIchanges b/doc/APIchanges index edeba02bff..c454cd2bb4 100644 --- a/doc/APIchanges +++ b/doc/APIchanges @@ -14,6 +14,8 @@ libavutil: 2015-08-28 API changes, most recent first: +2015-11-xx - xxxxxxx - lavu 55.8.100 - xtea.h + Add av_xtea_le_init and av_xtea_le_crypt 2015-11-18 - lavu 55.7.100 - mem.h Add av_fast_mallocz() diff --git a/libavformat/rtmpcrypt.c b/libavformat/rtmpcrypt.c index 2065ec6602..184bcf63fa 100644 --- a/libavformat/rtmpcrypt.c +++ b/libavformat/rtmpcrypt.c @@ -186,7 +186,7 @@ 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); + av_xtea_le_crypt(&ctx, out, in, 1, NULL, 0); } static void rtmpe9_sig(const uint8_t *in, uint8_t *out, int key_id) diff --git a/libavutil/version.h b/libavutil/version.h index 8198e6ded8..4520c52909 100644 --- a/libavutil/version.h +++ b/libavutil/version.h @@ -56,7 +56,7 @@ */ #define LIBAVUTIL_VERSION_MAJOR 55 -#define LIBAVUTIL_VERSION_MINOR 7 +#define LIBAVUTIL_VERSION_MINOR 8 #define LIBAVUTIL_VERSION_MICRO 100 #define LIBAVUTIL_VERSION_INT AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \ diff --git a/libavutil/xtea.c b/libavutil/xtea.c index 0d58cba832..2139aa5520 100644 --- a/libavutil/xtea.c +++ b/libavutil/xtea.c @@ -47,6 +47,14 @@ void av_xtea_init(AVXTEA *ctx, const uint8_t key[16]) ctx->key[i] = AV_RB32(key + (i << 2)); } +void av_xtea_le_init(AVXTEA *ctx, const uint8_t key[16]) +{ + int i; + + for (i = 0; i < 4; i++) + ctx->key[i] = AV_RL32(key + (i << 2)); +} + static void xtea_crypt_ecb(AVXTEA *ctx, uint8_t *dst, const uint8_t *src, int decrypt, uint8_t *iv) { @@ -167,14 +175,51 @@ static void xtea_crypt_ecb(AVXTEA *ctx, uint8_t *dst, const uint8_t *src, AV_WB32(dst + 4, v1); } -void av_xtea_crypt(AVXTEA *ctx, uint8_t *dst, const uint8_t *src, int count, - uint8_t *iv, int decrypt) +static void xtea_le_crypt_ecb(AVXTEA *ctx, uint8_t *dst, const uint8_t *src, + int decrypt, uint8_t *iv) +{ + uint32_t v0, v1; + int i; + + v0 = AV_RL32(src); + v1 = AV_RL32(src + 4); + + if (decrypt) { + uint32_t delta = 0x9E3779B9, sum = delta * 32; + + for (i = 0; i < 32; i++) { + v1 -= (((v0 << 4) ^ (v0 >> 5)) + v0) ^ (sum + ctx->key[(sum >> 11) & 3]); + sum -= delta; + v0 -= (((v1 << 4) ^ (v1 >> 5)) + v1) ^ (sum + ctx->key[sum & 3]); + } + if (iv) { + v0 ^= AV_RL32(iv); + v1 ^= AV_RL32(iv + 4); + memcpy(iv, src, 8); + } + } else { + uint32_t sum = 0, delta = 0x9E3779B9; + + for (i = 0; i < 32; i++) { + v0 += (((v1 << 4) ^ (v1 >> 5)) + v1) ^ (sum + ctx->key[sum & 3]); + sum += delta; + v1 += (((v0 << 4) ^ (v0 >> 5)) + v0) ^ (sum + ctx->key[(sum >> 11) & 3]); + } + } + + AV_WL32(dst, v0); + AV_WL32(dst + 4, v1); +} + +static void xtea_crypt(AVXTEA *ctx, uint8_t *dst, const uint8_t *src, int count, + uint8_t *iv, int decrypt, + void (*crypt)(AVXTEA *, uint8_t *, const uint8_t *, int, uint8_t *)) { int i; if (decrypt) { while (count--) { - xtea_crypt_ecb(ctx, dst, src, decrypt, iv); + crypt(ctx, dst, src, decrypt, iv); src += 8; dst += 8; @@ -184,10 +229,10 @@ void av_xtea_crypt(AVXTEA *ctx, uint8_t *dst, const uint8_t *src, int count, if (iv) { for (i = 0; i < 8; i++) dst[i] = src[i] ^ iv[i]; - xtea_crypt_ecb(ctx, dst, dst, decrypt, NULL); + crypt(ctx, dst, dst, decrypt, NULL); memcpy(iv, dst, 8); } else { - xtea_crypt_ecb(ctx, dst, src, decrypt, NULL); + crypt(ctx, dst, src, decrypt, NULL); } src += 8; dst += 8; @@ -195,6 +240,18 @@ void av_xtea_crypt(AVXTEA *ctx, uint8_t *dst, const uint8_t *src, int count, } } +void av_xtea_crypt(AVXTEA *ctx, uint8_t *dst, const uint8_t *src, int count, + uint8_t *iv, int decrypt) +{ + xtea_crypt(ctx, dst, src, count, iv, decrypt, xtea_crypt_ecb); +} + +void av_xtea_le_crypt(AVXTEA *ctx, uint8_t *dst, const uint8_t *src, int count, + uint8_t *iv, int decrypt) +{ + xtea_crypt(ctx, dst, src, count, iv, decrypt, xtea_le_crypt_ecb); +} + #ifdef TEST #include @@ -235,9 +292,10 @@ static const uint8_t xtea_test_ct[XTEA_NUM_TESTS][8] = { static void test_xtea(AVXTEA *ctx, uint8_t *dst, const uint8_t *src, const uint8_t *ref, int len, uint8_t *iv, int dir, - const char *test) + const char *test, + void (*crypt)(AVXTEA *, uint8_t *, const uint8_t *, int, uint8_t *, int)) { - av_xtea_crypt(ctx, dst, src, len, iv, dir); + crypt(ctx, dst, src, len, iv, dir); if (memcmp(dst, ref, 8*len)) { int i; printf("%s failed\ngot ", test); @@ -254,8 +312,8 @@ static void test_xtea(AVXTEA *ctx, uint8_t *dst, const uint8_t *src, int main(void) { AVXTEA ctx; - uint8_t buf[8], iv[8]; - int i; + uint8_t buf[16], iv[8]; + int i, j; static const uint8_t src[32] = "HelloWorldHelloWorldHelloWorld"; uint8_t ct[32]; uint8_t pl[32]; @@ -263,8 +321,18 @@ int main(void) for (i = 0; i < XTEA_NUM_TESTS; i++) { av_xtea_init(&ctx, xtea_test_key[i]); - test_xtea(&ctx, buf, xtea_test_pt[i], xtea_test_ct[i], 1, NULL, 0, "encryption"); - test_xtea(&ctx, buf, xtea_test_ct[i], xtea_test_pt[i], 1, NULL, 1, "decryption"); + test_xtea(&ctx, buf, xtea_test_pt[i], xtea_test_ct[i], 1, NULL, 0, "encryption", av_xtea_crypt); + test_xtea(&ctx, buf, xtea_test_ct[i], xtea_test_pt[i], 1, NULL, 1, "decryption", av_xtea_crypt); + + for (j = 0; j < 4; j++) + AV_WL32(&buf[4*j], AV_RB32(&xtea_test_key[i][4*j])); + av_xtea_le_init(&ctx, buf); + for (j = 0; j < 2; j++) { + AV_WL32(&ct[4*j], AV_RB32(&xtea_test_ct[i][4*j])); + AV_WL32(&pl[4*j], AV_RB32(&xtea_test_pt[i][4*j])); + } + test_xtea(&ctx, buf, pl, ct, 1, NULL, 0, "encryption", av_xtea_le_crypt); + test_xtea(&ctx, buf, ct, pl, 1, NULL, 1, "decryption", av_xtea_le_crypt); /* encrypt */ memcpy(iv, "HALLO123", 8); @@ -272,10 +340,10 @@ int main(void) /* decrypt into pl */ memcpy(iv, "HALLO123", 8); - test_xtea(&ctx, pl, ct, src, 4, iv, 1, "CBC decryption"); + test_xtea(&ctx, pl, ct, src, 4, iv, 1, "CBC decryption", av_xtea_crypt); memcpy(iv, "HALLO123", 8); - test_xtea(&ctx, ct, ct, src, 4, iv, 1, "CBC inplace decryption"); + test_xtea(&ctx, ct, ct, src, 4, iv, 1, "CBC inplace decryption", av_xtea_crypt); } printf("Test encryption/decryption success.\n"); diff --git a/libavutil/xtea.h b/libavutil/xtea.h index 06f5a2f470..735427c109 100644 --- a/libavutil/xtea.h +++ b/libavutil/xtea.h @@ -50,6 +50,15 @@ AVXTEA *av_xtea_alloc(void); */ void av_xtea_init(struct AVXTEA *ctx, const uint8_t key[16]); +/** + * Initialize an AVXTEA context. + * + * @param ctx an AVXTEA context + * @param key a key of 16 bytes used for encryption/decryption, + * interpreted as little endian 32 bit numbers + */ +void av_xtea_le_init(struct AVXTEA *ctx, const uint8_t key[16]); + /** * Encrypt or decrypt a buffer using a previously initialized context, * in big endian format. @@ -64,6 +73,20 @@ void av_xtea_init(struct AVXTEA *ctx, const uint8_t key[16]); void av_xtea_crypt(struct AVXTEA *ctx, uint8_t *dst, const uint8_t *src, int count, uint8_t *iv, int decrypt); +/** + * Encrypt or decrypt a buffer using a previously initialized context, + * in little endian format. + * + * @param ctx an AVXTEA context + * @param dst destination array, can be equal to src + * @param src source array, can be equal to dst + * @param count number of 8 byte blocks + * @param iv initialization vector for CBC mode, if NULL then ECB will be used + * @param decrypt 0 for encryption, 1 for decryption + */ +void av_xtea_le_crypt(struct AVXTEA *ctx, uint8_t *dst, const uint8_t *src, + int count, uint8_t *iv, int decrypt); + /** * @} */