+++ /dev/null
-/* Modified for SILC. -Pekka */
-
-/* This is an independent implementation of the encryption algorithm: */
-/* */
-/* MARS by a team at IBM, */
-/* */
-/* which is a candidate algorithm in the Advanced Encryption Standard */
-/* programme of the US National Institute of Standards and Technology. */
-/* Copyright in this implementation is held by Dr B R Gladman. The MARS */
-/* algorithm is covered by a pending patent application owned by IBM, */
-/* who intend to offer a royalty free license under any issued patent */
-/* that results from such application if MARS is selected as the AES */
-/* algorithm. In the interim, you may evaluate the MARS algorithm for */
-/* your personal, lawful, non-profit purposes as an end user. */
-/* */
-/* The header above modified on June 6th 1999. */
-/* Dr Brian Gladman (gladman@seven77.demon.co.uk) 14th January 1999 */
-
-/* Timing data for MARS (mars.c)
-
-128 bit key:
-Key Setup: 4316 cycles
-Encrypt: 369 cycles = 69.4 mbits/sec
-Decrypt: 376 cycles = 68.1 mbits/sec
-Mean: 373 cycles = 68.7 mbits/sec
-
-192 bit key:
-Key Setup: 4377 cycles
-Encrypt: 373 cycles = 68.6 mbits/sec
-Decrypt: 379 cycles = 67.5 mbits/sec
-Mean: 376 cycles = 68.1 mbits/sec
-
-256 bit key:
-Key Setup: 4340 cycles
-Encrypt: 369 cycles = 69.4 mbits/sec
-Decrypt: 376 cycles = 68.1 mbits/sec
-Mean: 373 cycles = 68.7 mbits/sec
-
-*/
-
-#include "silcincludes.h"
-#include "mars_internal.h"
-#include "mars.h"
-
-/*
- * SILC Crypto API for MARS
- */
-
-/* Sets the key for cipher MARS. */
-
-SILC_CIPHER_API_SET_KEY(mars)
-{
- SilcUInt32 k[8];
-
- SILC_GET_WORD_KEY(key, k, keylen);
- mars_set_key((MarsContext *)context, k, keylen);
-
- return TRUE;
-}
-
-/* Sets the string as a new key for the cipher MARS. The string
- is first hashed and then used as a new key. */
-
-SILC_CIPHER_API_SET_KEY_WITH_STRING(mars)
-{
- /* unsigned char key[md5_hash_len];
- SilcMarsContext *ctx = (SilcMarsContext *)context;
-
- make_md5_hash(string, &key);
- memcpy(&ctx->key, mars_set_key(&key, keylen), keylen);
- memset(&key, 'F', sizeoof(key));
- */
- return TRUE;
-}
-
-/* Returns the size of the MARS cipher context. */
-
-SILC_CIPHER_API_CONTEXT_LEN(mars)
-{
- return sizeof(MarsContext);
-}
-
-/* Encrypts with MARS cipher in CBC mode. Source and destination buffers
- maybe one and same. */
-
-SILC_CIPHER_API_ENCRYPT_CBC(mars)
-{
- SilcUInt32 tiv[4];
- int i;
-
- SILC_CBC_GET_IV(tiv, iv);
-
- SILC_CBC_ENC_PRE(tiv, src);
- mars_encrypt((MarsContext *)context, tiv, tiv);
- SILC_CBC_ENC_POST(tiv, dst, src);
-
- for (i = 16; i < len; i += 16) {
- SILC_CBC_ENC_PRE(tiv, src);
- mars_encrypt((MarsContext *)context, tiv, tiv);
- SILC_CBC_ENC_POST(tiv, dst, src);
- }
-
- SILC_CBC_PUT_IV(tiv, iv);
-
- return TRUE;
-}
-
-/* Decrypts with MARS cipher in CBC mode. Source and destination buffers
- maybe one and same. */
-
-SILC_CIPHER_API_DECRYPT_CBC(mars)
-{
- SilcUInt32 tmp[4], tmp2[4], tiv[4];
- int i;
-
- SILC_CBC_GET_IV(tiv, iv);
-
- SILC_CBC_DEC_PRE(tmp, src);
- mars_decrypt((MarsContext *)context, tmp, tmp2);
- SILC_CBC_DEC_POST(tmp2, dst, src, tmp, tiv);
-
- for (i = 16; i < len; i += 16) {
- SILC_CBC_DEC_PRE(tmp, src);
- mars_decrypt((MarsContext *)context, tmp, tmp2);
- SILC_CBC_DEC_POST(tmp2, dst, src, tmp, tiv);
- }
-
- SILC_CBC_PUT_IV(tiv, iv);
-
- return TRUE;
-}
-
-static u4byte s_box[] =
-{
- 0x09d0c479, 0x28c8ffe0, 0x84aa6c39, 0x9dad7287, /* 0x000 */
- 0x7dff9be3, 0xd4268361, 0xc96da1d4, 0x7974cc93,
- 0x85d0582e, 0x2a4b5705, 0x1ca16a62, 0xc3bd279d,
- 0x0f1f25e5, 0x5160372f, 0xc695c1fb, 0x4d7ff1e4,
- 0xae5f6bf4, 0x0d72ee46, 0xff23de8a, 0xb1cf8e83, /* 0x010 */
- 0xf14902e2, 0x3e981e42, 0x8bf53eb6, 0x7f4bf8ac,
- 0x83631f83, 0x25970205, 0x76afe784, 0x3a7931d4,
- 0x4f846450, 0x5c64c3f6, 0x210a5f18, 0xc6986a26,
- 0x28f4e826, 0x3a60a81c, 0xd340a664, 0x7ea820c4, /* 0x020 */
- 0x526687c5, 0x7eddd12b, 0x32a11d1d, 0x9c9ef086,
- 0x80f6e831, 0xab6f04ad, 0x56fb9b53, 0x8b2e095c,
- 0xb68556ae, 0xd2250b0d, 0x294a7721, 0xe21fb253,
- 0xae136749, 0xe82aae86, 0x93365104, 0x99404a66, /* 0x030 */
- 0x78a784dc, 0xb69ba84b, 0x04046793, 0x23db5c1e,
- 0x46cae1d6, 0x2fe28134, 0x5a223942, 0x1863cd5b,
- 0xc190c6e3, 0x07dfb846, 0x6eb88816, 0x2d0dcc4a,
- 0xa4ccae59, 0x3798670d, 0xcbfa9493, 0x4f481d45, /* 0x040 */
- 0xeafc8ca8, 0xdb1129d6, 0xb0449e20, 0x0f5407fb,
- 0x6167d9a8, 0xd1f45763, 0x4daa96c3, 0x3bec5958,
- 0xababa014, 0xb6ccd201, 0x38d6279f, 0x02682215,
- 0x8f376cd5, 0x092c237e, 0xbfc56593, 0x32889d2c, /* 0x050 */
- 0x854b3e95, 0x05bb9b43, 0x7dcd5dcd, 0xa02e926c,
- 0xfae527e5, 0x36a1c330, 0x3412e1ae, 0xf257f462,
- 0x3c4f1d71, 0x30a2e809, 0x68e5f551, 0x9c61ba44,
- 0x5ded0ab8, 0x75ce09c8, 0x9654f93e, 0x698c0cca, /* 0x060 */
- 0x243cb3e4, 0x2b062b97, 0x0f3b8d9e, 0x00e050df,
- 0xfc5d6166, 0xe35f9288, 0xc079550d, 0x0591aee8,
- 0x8e531e74, 0x75fe3578, 0x2f6d829a, 0xf60b21ae,
- 0x95e8eb8d, 0x6699486b, 0x901d7d9b, 0xfd6d6e31, /* 0x070 */
- 0x1090acef, 0xe0670dd8, 0xdab2e692, 0xcd6d4365,
- 0xe5393514, 0x3af345f0, 0x6241fc4d, 0x460da3a3,
- 0x7bcf3729, 0x8bf1d1e0, 0x14aac070, 0x1587ed55,
- 0x3afd7d3e, 0xd2f29e01, 0x29a9d1f6, 0xefb10c53, /* 0x080 */
- 0xcf3b870f, 0xb414935c, 0x664465ed, 0x024acac7,
- 0x59a744c1, 0x1d2936a7, 0xdc580aa6, 0xcf574ca8,
- 0x040a7a10, 0x6cd81807, 0x8a98be4c, 0xaccea063,
- 0xc33e92b5, 0xd1e0e03d, 0xb322517e, 0x2092bd13, /* 0x090 */
- 0x386b2c4a, 0x52e8dd58, 0x58656dfb, 0x50820371,
- 0x41811896, 0xe337ef7e, 0xd39fb119, 0xc97f0df6,
- 0x68fea01b, 0xa150a6e5, 0x55258962, 0xeb6ff41b,
- 0xd7c9cd7a, 0xa619cd9e, 0xbcf09576, 0x2672c073, /* 0x0a0 */
- 0xf003fb3c, 0x4ab7a50b, 0x1484126a, 0x487ba9b1,
- 0xa64fc9c6, 0xf6957d49, 0x38b06a75, 0xdd805fcd,
- 0x63d094cf, 0xf51c999e, 0x1aa4d343, 0xb8495294,
- 0xce9f8e99, 0xbffcd770, 0xc7c275cc, 0x378453a7, /* 0x0b0 */
- 0x7b21be33, 0x397f41bd, 0x4e94d131, 0x92cc1f98,
- 0x5915ea51, 0x99f861b7, 0xc9980a88, 0x1d74fd5f,
- 0xb0a495f8, 0x614deed0, 0xb5778eea, 0x5941792d,
- 0xfa90c1f8, 0x33f824b4, 0xc4965372, 0x3ff6d550, /* 0x0c0 */
- 0x4ca5fec0, 0x8630e964, 0x5b3fbbd6, 0x7da26a48,
- 0xb203231a, 0x04297514, 0x2d639306, 0x2eb13149,
- 0x16a45272, 0x532459a0, 0x8e5f4872, 0xf966c7d9,
- 0x07128dc0, 0x0d44db62, 0xafc8d52d, 0x06316131, /* 0x0d0 */
- 0xd838e7ce, 0x1bc41d00, 0x3a2e8c0f, 0xea83837e,
- 0xb984737d, 0x13ba4891, 0xc4f8b949, 0xa6d6acb3,
- 0xa215cdce, 0x8359838b, 0x6bd1aa31, 0xf579dd52,
- 0x21b93f93, 0xf5176781, 0x187dfdde, 0xe94aeb76, /* 0x0e0 */
- 0x2b38fd54, 0x431de1da, 0xab394825, 0x9ad3048f,
- 0xdfea32aa, 0x659473e3, 0x623f7863, 0xf3346c59,
- 0xab3ab685, 0x3346a90b, 0x6b56443e, 0xc6de01f8,
- 0x8d421fc0, 0x9b0ed10c, 0x88f1a1e9, 0x54c1f029, /* 0x0f0 */
- 0x7dead57b, 0x8d7ba426, 0x4cf5178a, 0x551a7cca,
- 0x1a9a5f08, 0xfcd651b9, 0x25605182, 0xe11fc6c3,
- 0xb6fd9676, 0x337b3027, 0xb7c8eb14, 0x9e5fd030,
-
- 0x6b57e354, 0xad913cf7, 0x7e16688d, 0x58872a69, /* 0x100 */
- 0x2c2fc7df, 0xe389ccc6, 0x30738df1, 0x0824a734,
- 0xe1797a8b, 0xa4a8d57b, 0x5b5d193b, 0xc8a8309b,
- 0x73f9a978, 0x73398d32, 0x0f59573e, 0xe9df2b03,
- 0xe8a5b6c8, 0x848d0704, 0x98df93c2, 0x720a1dc3, /* 0x110 */
- 0x684f259a, 0x943ba848, 0xa6370152, 0x863b5ea3,
- 0xd17b978b, 0x6d9b58ef, 0x0a700dd4, 0xa73d36bf,
- 0x8e6a0829, 0x8695bc14, 0xe35b3447, 0x933ac568,
- 0x8894b022, 0x2f511c27, 0xddfbcc3c, 0x006662b6, /* 0x120 */
- 0x117c83fe, 0x4e12b414, 0xc2bca766, 0x3a2fec10,
- 0xf4562420, 0x55792e2a, 0x46f5d857, 0xceda25ce,
- 0xc3601d3b, 0x6c00ab46, 0xefac9c28, 0xb3c35047,
- 0x611dfee3, 0x257c3207, 0xfdd58482, 0x3b14d84f, /* 0x130 */
- 0x23becb64, 0xa075f3a3, 0x088f8ead, 0x07adf158,
- 0x7796943c, 0xfacabf3d, 0xc09730cd, 0xf7679969,
- 0xda44e9ed, 0x2c854c12, 0x35935fa3, 0x2f057d9f,
- 0x690624f8, 0x1cb0bafd, 0x7b0dbdc6, 0x810f23bb, /* 0x140 */
- 0xfa929a1a, 0x6d969a17, 0x6742979b, 0x74ac7d05,
- 0x010e65c4, 0x86a3d963, 0xf907b5a0, 0xd0042bd3,
- 0x158d7d03, 0x287a8255, 0xbba8366f, 0x096edc33,
- 0x21916a7b, 0x77b56b86, 0x951622f9, 0xa6c5e650, /* 0x150 */
- 0x8cea17d1, 0xcd8c62bc, 0xa3d63433, 0x358a68fd,
- 0x0f9b9d3c, 0xd6aa295b, 0xfe33384a, 0xc000738e,
- 0xcd67eb2f, 0xe2eb6dc2, 0x97338b02, 0x06c9f246,
- 0x419cf1ad, 0x2b83c045, 0x3723f18a, 0xcb5b3089, /* 0x160 */
- 0x160bead7, 0x5d494656, 0x35f8a74b, 0x1e4e6c9e,
- 0x000399bd, 0x67466880, 0xb4174831, 0xacf423b2,
- 0xca815ab3, 0x5a6395e7, 0x302a67c5, 0x8bdb446b,
- 0x108f8fa4, 0x10223eda, 0x92b8b48b, 0x7f38d0ee, /* 0x170 */
- 0xab2701d4, 0x0262d415, 0xaf224a30, 0xb3d88aba,
- 0xf8b2c3af, 0xdaf7ef70, 0xcc97d3b7, 0xe9614b6c,
- 0x2baebff4, 0x70f687cf, 0x386c9156, 0xce092ee5,
- 0x01e87da6, 0x6ce91e6a, 0xbb7bcc84, 0xc7922c20, /* 0x180 */
- 0x9d3b71fd, 0x060e41c6, 0xd7590f15, 0x4e03bb47,
- 0x183c198e, 0x63eeb240, 0x2ddbf49a, 0x6d5cba54,
- 0x923750af, 0xf9e14236, 0x7838162b, 0x59726c72,
- 0x81b66760, 0xbb2926c1, 0x48a0ce0d, 0xa6c0496d, /* 0x190 */
- 0xad43507b, 0x718d496a, 0x9df057af, 0x44b1bde6,
- 0x054356dc, 0xde7ced35, 0xd51a138b, 0x62088cc9,
- 0x35830311, 0xc96efca2, 0x686f86ec, 0x8e77cb68,
- 0x63e1d6b8, 0xc80f9778, 0x79c491fd, 0x1b4c67f2, /* 0x1a0 */
- 0x72698d7d, 0x5e368c31, 0xf7d95e2e, 0xa1d3493f,
- 0xdcd9433e, 0x896f1552, 0x4bc4ca7a, 0xa6d1baf4,
- 0xa5a96dcc, 0x0bef8b46, 0xa169fda7, 0x74df40b7,
- 0x4e208804, 0x9a756607, 0x038e87c8, 0x20211e44, /* 0x1b0 */
- 0x8b7ad4bf, 0xc6403f35, 0x1848e36d, 0x80bdb038,
- 0x1e62891c, 0x643d2107, 0xbf04d6f8, 0x21092c8c,
- 0xf644f389, 0x0778404e, 0x7b78adb8, 0xa2c52d53,
- 0x42157abe, 0xa2253e2e, 0x7bf3f4ae, 0x80f594f9, /* 0x1c0 */
- 0x953194e7, 0x77eb92ed, 0xb3816930, 0xda8d9336,
- 0xbf447469, 0xf26d9483, 0xee6faed5, 0x71371235,
- 0xde425f73, 0xb4e59f43, 0x7dbe2d4e, 0x2d37b185,
- 0x49dc9a63, 0x98c39d98, 0x1301c9a2, 0x389b1bbf, /* 0x1d0 */
- 0x0c18588d, 0xa421c1ba, 0x7aa3865c, 0x71e08558,
- 0x3c5cfcaa, 0x7d239ca4, 0x0297d9dd, 0xd7dc2830,
- 0x4b37802b, 0x7428ab54, 0xaeee0347, 0x4b3fbb85,
- 0x692f2f08, 0x134e578e, 0x36d9e0bf, 0xae8b5fcf, /* 0x1e0 */
- 0xedb93ecf, 0x2b27248e, 0x170eb1ef, 0x7dc57fd6,
- 0x1e760f16, 0xb1136601, 0x864e1b9b, 0xd7ea7319,
- 0x3ab871bd, 0xcfa4d76f, 0xe31bd782, 0x0dbeb469,
- 0xabb96061, 0x5370f85d, 0xffb07e37, 0xda30d0fb, /* 0x1f0 */
- 0xebc977b6, 0x0b98b40f, 0x3a4d0fe6, 0xdf4fc26b,
- 0x159cf22a, 0xc298d6e2, 0x2b78ef6a, 0x61a94ac0,
- 0xab561187, 0x14eea0f0, 0xdf0d4164, 0x19af70ee
-};
-
-static u4byte vk[47] =
-{
- 0x09d0c479, 0x28c8ffe0, 0x84aa6c39, 0x9dad7287, 0x7dff9be3, 0xd4268361,
- 0xc96da1d4
-};
-
-#define f_mix(a,b,c,d) \
- r = rotr(a, 8); \
- b ^= s_box[a & 255]; \
- b += s_box[(r & 255) + 256]; \
- r = rotr(a, 16); \
- a = rotr(a, 24); \
- c += s_box[r & 255]; \
- d ^= s_box[(a & 255) + 256]
-
-#define b_mix(a,b,c,d) \
- r = rotl(a, 8); \
- b ^= s_box[(a & 255) + 256]; \
- c -= s_box[r & 255]; \
- r = rotl(a, 16); \
- a = rotl(a, 24); \
- d -= s_box[(r & 255) + 256]; \
- d ^= s_box[a & 255]
-
-#define f_ktr(a,b,c,d,i) \
- m = a + l_key[i]; \
- a = rotl(a, 13); \
- r = a * l_key[i + 1]; \
- l = s_box[m & 511]; \
- r = rotl(r, 5); \
- c += rotl(m, r); \
- l ^= r; \
- r = rotl(r, 5); \
- l ^= r; \
- d ^= r; \
- b += rotl(l, r)
-
-#define r_ktr(a,b,c,d,i) \
- r = a * l_key[i + 1]; \
- a = rotr(a, 13); \
- m = a + l_key[i]; \
- l = s_box[m & 511]; \
- r = rotl(r, 5); \
- l ^= r; \
- c -= rotl(m, r); \
- r = rotl(r, 5); \
- l ^= r; \
- d ^= r; \
- b -= rotl(l, r)
-
-/* For a 32 bit word (x) generate a mask (m) such that a bit in */
-/* m is set to 1 if and only if the corresponding bit in x is: */
-/* */
-/* 1. in a sequence of 10 or more adjacent '0' bits */
-/* 2. in a sequence of 10 or more adjacent '1' bits */
-/* 3. but is not either endpoint of such a sequence unless such */
-/* an endpoint is at the top bit (bit 31) of a word and is */
-/* in a sequence of '0' bits. */
-/* */
-/* The only situation in which a sequence endpoint is included */
-/* in the mask is hence when the endpoint is at bit 31 and is */
-/* the endpoint of a sequence of '0' bits. My thanks go to Shai */
-/* Halevi of IBM for the neat trick (which I missed) of finding */
-/* the '0' and '1' sequences at the same time. */
-
-u4byte gen_mask(u4byte x)
-{ u4byte m;
-
- /* if m{bn} stands for bit number bn of m, set m{bn} = 1 if */
- /* x{bn} == x{bn+1} for 0 <= bn <= 30. That is, set a bit */
- /* in m if the corresponding bit and the next higher bit in */
- /* x are equal in value (set m{31} = 0). */
-
- m = (~x ^ (x >> 1)) & 0x7fffffff;
-
- /* Sequences of 9 '1' bits in m now correspond to sequences */
- /* of 10 '0's or 10 '1' bits in x. Shift and 'and' bits in */
- /* m to find sequences of 9 or more '1' bits. As a result */
- /* bits in m are set if they are at the bottom of sequences */
- /* of 10 adjacent '0's or 10 adjacent '1's in x. */
-
- m &= (m >> 1) & (m >> 2); m &= (m >> 3) & (m >> 6);
-
- if(!m) /* return if mask is empty - no key fixing needed */
- /* is this early return worthwhile? */
- return 0;
-
- /* We need the internal bits in each continuous sequence of */
- /* matching bits (that is the bits less the two endpoints). */
- /* We thus propagate each set bit into the 8 internal bits */
- /* that it represents, starting 1 left and finsihing 8 left */
- /* of its position. */
-
- m <<= 1; m |= (m << 1); m |= (m << 2); m |= (m << 4);
-
- /* m is now correct except for the odd behaviour of bit 31, */
- /* that is, it will be set if it is in a sequence of 10 or */
- /* more '0's and clear otherwise. */
-
- m |= (m << 1) & ~x & 0x80000000;
-
- return m & 0xfffffffc;
-};
-
-/* My thanks to Louis Granboulan for spotting an error in the */
-/* previous version of set_key. */
-
-u4byte *mars_set_key(MarsContext *ctx,
- const u4byte in_key[], const u4byte key_len)
-{
- u4byte i, j, m, w;
- u4byte *l_key = ctx->l_key;
-
- m = key_len / 32 - 1;
-
- for(i = j = 0; i < 39; ++i)
- {
- vk[i + 7] = rotl(vk[i] ^ vk[i + 5], 3) ^ in_key[j] ^ i;
-
- j = (j == m ? 0 : j + 1);
- }
-
- vk[46] = key_len / 32;
-
- for(j = 0; j < 7; ++j)
- {
- for(i = 1; i < 40; ++i)
-
- vk[i + 7] = rotl(vk[i + 7] + s_box[vk[i + 6] & 511], 9);
-
- vk[7] = rotl(vk[7] + s_box[vk[46] & 511], 9);
- }
-
- for(i = j = 0; i < 40; ++i)
- {
- l_key[j] = vk[i + 7];
-
- j = (j < 33 ? j + 7 : j - 33);
- }
-
- for(i = 5; i < 37; i += 2)
- {
- w = l_key[i] | 3;
-
- if((m = gen_mask(w)))
-
- w ^= (rotl(s_box[265 + (l_key[i] & 3)], l_key[i + 3] & 31) & m);
-
- l_key[i] = w;
- }
-
- return l_key;
-};
-
-void mars_encrypt(MarsContext *ctx,
- const u4byte in_blk[4], u4byte out_blk[4])
-{
- u4byte a, b, c, d, l, m, r;
- u4byte *l_key = ctx->l_key;
-
- a = in_blk[0] + l_key[0]; b = in_blk[1] + l_key[1];
- c = in_blk[2] + l_key[2]; d = in_blk[3] + l_key[3];
-
- f_mix(a,b,c,d); a += d;
- f_mix(b,c,d,a); b += c;
- f_mix(c,d,a,b);
- f_mix(d,a,b,c);
- f_mix(a,b,c,d); a += d;
- f_mix(b,c,d,a); b += c;
- f_mix(c,d,a,b);
- f_mix(d,a,b,c);
-
- f_ktr(a,b,c,d, 4); f_ktr(b,c,d,a, 6); f_ktr(c,d,a,b, 8); f_ktr(d,a,b,c,10);
- f_ktr(a,b,c,d,12); f_ktr(b,c,d,a,14); f_ktr(c,d,a,b,16); f_ktr(d,a,b,c,18);
- f_ktr(a,d,c,b,20); f_ktr(b,a,d,c,22); f_ktr(c,b,a,d,24); f_ktr(d,c,b,a,26);
- f_ktr(a,d,c,b,28); f_ktr(b,a,d,c,30); f_ktr(c,b,a,d,32); f_ktr(d,c,b,a,34);
-
- b_mix(a,b,c,d);
- b_mix(b,c,d,a); c -= b;
- b_mix(c,d,a,b); d -= a;
- b_mix(d,a,b,c);
- b_mix(a,b,c,d);
- b_mix(b,c,d,a); c -= b;
- b_mix(c,d,a,b); d -= a;
- b_mix(d,a,b,c);
-
- out_blk[0] = a - l_key[36]; out_blk[1] = b - l_key[37];
- out_blk[2] = c - l_key[38]; out_blk[3] = d - l_key[39];
-};
-
-void mars_decrypt(MarsContext *ctx,
- const u4byte in_blk[4], u4byte out_blk[4])
-{
- u4byte a, b, c, d, l, m, r;
- u4byte *l_key = ctx->l_key;
-
- d = in_blk[0] + l_key[36]; c = in_blk[1] + l_key[37];
- b = in_blk[2] + l_key[38]; a = in_blk[3] + l_key[39];
-
- f_mix(a,b,c,d); a += d;
- f_mix(b,c,d,a); b += c;
- f_mix(c,d,a,b);
- f_mix(d,a,b,c);
- f_mix(a,b,c,d); a += d;
- f_mix(b,c,d,a); b += c;
- f_mix(c,d,a,b);
- f_mix(d,a,b,c);
-
- r_ktr(a,b,c,d,34); r_ktr(b,c,d,a,32); r_ktr(c,d,a,b,30); r_ktr(d,a,b,c,28);
- r_ktr(a,b,c,d,26); r_ktr(b,c,d,a,24); r_ktr(c,d,a,b,22); r_ktr(d,a,b,c,20);
- r_ktr(a,d,c,b,18); r_ktr(b,a,d,c,16); r_ktr(c,b,a,d,14); r_ktr(d,c,b,a,12);
- r_ktr(a,d,c,b,10); r_ktr(b,a,d,c, 8); r_ktr(c,b,a,d, 6); r_ktr(d,c,b,a, 4);
-
- b_mix(a,b,c,d);
- b_mix(b,c,d,a); c -= b;
- b_mix(c,d,a,b); d -= a;
- b_mix(d,a,b,c);
- b_mix(a,b,c,d);
- b_mix(b,c,d,a); c -= b;
- b_mix(c,d,a,b); d -= a;
- b_mix(d,a,b,c);
-
- out_blk[0] = d - l_key[0]; out_blk[1] = c - l_key[1];
- out_blk[2] = b - l_key[2]; out_blk[3] = a - l_key[3];
-}