diff options
Diffstat (limited to 'libavutil/xtea.c')
-rw-r--r-- | libavutil/xtea.c | 97 |
1 files changed, 90 insertions, 7 deletions
diff --git a/libavutil/xtea.c b/libavutil/xtea.c index f3357ce..28780fb 100644 --- a/libavutil/xtea.c +++ b/libavutil/xtea.c @@ -4,20 +4,20 @@ * * loosely based on the implementation of David Wheeler and Roger Needham * - * This file is part of Libav. + * This file is part of FFmpeg. * - * Libav is free software; you can redistribute it and/or + * 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. * - * Libav is distributed in the hope that it will be useful, + * 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 Libav; if not, write to the Free Software + * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ @@ -39,32 +39,114 @@ static void xtea_crypt_ecb(AVXTEA *ctx, uint8_t *dst, const uint8_t *src, int decrypt, uint8_t *iv) { uint32_t v0, v1; - int i; + uint32_t k0 = ctx->key[0]; + uint32_t k1 = ctx->key[1]; + uint32_t k2 = ctx->key[2]; + uint32_t k3 = ctx->key[3]; v0 = AV_RB32(src); v1 = AV_RB32(src + 4); if (decrypt) { - uint32_t delta = 0x9E3779B9, sum = delta * 32; +#if CONFIG_SMALL + int i; + uint32_t delta = 0x9E3779B9U, 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]); } +#else +#define DSTEP(SUM, K0, K1) \ + v1 -= (((v0 << 4) ^ (v0 >> 5)) + v0) ^ (SUM + K0); \ + v0 -= (((v1 << 4) ^ (v1 >> 5)) + v1) ^ (SUM - 0x9E3779B9U + K1) + + DSTEP(0xC6EF3720U, k2, k3); + DSTEP(0x28B7BD67U, k3, k2); + DSTEP(0x8A8043AEU, k0, k1); + DSTEP(0xEC48C9F5U, k1, k0); + DSTEP(0x4E11503CU, k2, k3); + DSTEP(0xAFD9D683U, k2, k2); + DSTEP(0x11A25CCAU, k3, k1); + DSTEP(0x736AE311U, k0, k0); + DSTEP(0xD5336958U, k1, k3); + DSTEP(0x36FBEF9FU, k1, k2); + DSTEP(0x98C475E6U, k2, k1); + DSTEP(0xFA8CFC2DU, k3, k0); + DSTEP(0x5C558274U, k0, k3); + DSTEP(0xBE1E08BBU, k1, k2); + DSTEP(0x1FE68F02U, k1, k1); + DSTEP(0x81AF1549U, k2, k0); + DSTEP(0xE3779B90U, k3, k3); + DSTEP(0x454021D7U, k0, k2); + DSTEP(0xA708A81EU, k1, k1); + DSTEP(0x08D12E65U, k1, k0); + DSTEP(0x6A99B4ACU, k2, k3); + DSTEP(0xCC623AF3U, k3, k2); + DSTEP(0x2E2AC13AU, k0, k1); + DSTEP(0x8FF34781U, k0, k0); + DSTEP(0xF1BBCDC8U, k1, k3); + DSTEP(0x5384540FU, k2, k2); + DSTEP(0xB54CDA56U, k3, k1); + DSTEP(0x1715609DU, k0, k0); + DSTEP(0x78DDE6E4U, k0, k3); + DSTEP(0xDAA66D2BU, k1, k2); + DSTEP(0x3C6EF372U, k2, k1); + DSTEP(0x9E3779B9U, k3, k0); +#endif if (iv) { v0 ^= AV_RB32(iv); v1 ^= AV_RB32(iv + 4); memcpy(iv, src, 8); } } else { - uint32_t sum = 0, delta = 0x9E3779B9; +#if CONFIG_SMALL + int i; + uint32_t sum = 0, delta = 0x9E3779B9U; 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]); } +#else +#define ESTEP(SUM, K0, K1) \ + v0 += (((v1 << 4) ^ (v1 >> 5)) + v1) ^ (SUM + K0);\ + v1 += (((v0 << 4) ^ (v0 >> 5)) + v0) ^ (SUM + 0x9E3779B9U + K1) + ESTEP(0x00000000U, k0, k3); + ESTEP(0x9E3779B9U, k1, k2); + ESTEP(0x3C6EF372U, k2, k1); + ESTEP(0xDAA66D2BU, k3, k0); + ESTEP(0x78DDE6E4U, k0, k0); + ESTEP(0x1715609DU, k1, k3); + ESTEP(0xB54CDA56U, k2, k2); + ESTEP(0x5384540FU, k3, k1); + ESTEP(0xF1BBCDC8U, k0, k0); + ESTEP(0x8FF34781U, k1, k0); + ESTEP(0x2E2AC13AU, k2, k3); + ESTEP(0xCC623AF3U, k3, k2); + ESTEP(0x6A99B4ACU, k0, k1); + ESTEP(0x08D12E65U, k1, k1); + ESTEP(0xA708A81EU, k2, k0); + ESTEP(0x454021D7U, k3, k3); + ESTEP(0xE3779B90U, k0, k2); + ESTEP(0x81AF1549U, k1, k1); + ESTEP(0x1FE68F02U, k2, k1); + ESTEP(0xBE1E08BBU, k3, k0); + ESTEP(0x5C558274U, k0, k3); + ESTEP(0xFA8CFC2DU, k1, k2); + ESTEP(0x98C475E6U, k2, k1); + ESTEP(0x36FBEF9FU, k3, k1); + ESTEP(0xD5336958U, k0, k0); + ESTEP(0x736AE311U, k1, k3); + ESTEP(0x11A25CCAU, k2, k2); + ESTEP(0xAFD9D683U, k3, k2); + ESTEP(0x4E11503CU, k0, k1); + ESTEP(0xEC48C9F5U, k1, k0); + ESTEP(0x8A8043AEU, k2, k3); + ESTEP(0x28B7BD67U, k3, k2); +#endif } AV_WB32(dst, v0); @@ -183,6 +265,7 @@ int main(void) memcpy(iv, "HALLO123", 8); test_xtea(&ctx, ct, ct, src, 4, iv, 1, "CBC inplace decryption"); } + printf("Test encryption/decryption success.\n"); return 0; |