Mercurial > dropbear
diff src/ciphers/safer/safer.c @ 192:9cc34777b479 libtomcrypt
propagate from branch 'au.asn.ucc.matt.ltc-orig' (head 9ba8f01f44320e9cb9f19881105ae84f84a43ea9)
to branch 'au.asn.ucc.matt.dropbear.ltc' (head dbf51c569bc34956ad948e4cc87a0eeb2170b768)
author | Matt Johnston <matt@ucc.asn.au> |
---|---|
date | Sun, 08 May 2005 06:36:47 +0000 |
parents | 1c15b283127b |
children | 39d5d58461d6 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/ciphers/safer/safer.c Sun May 08 06:36:47 2005 +0000 @@ -0,0 +1,483 @@ +/* LibTomCrypt, modular cryptographic library -- Tom St Denis + * + * LibTomCrypt is a library that provides various cryptographic + * algorithms in a highly modular and flexible manner. + * + * The library is free for all purposes without any express + * guarantee it works. + * + * Tom St Denis, [email protected], http://libtomcrypt.org + */ + +/******************************************************************************* +* +* FILE: safer.c +* +* DESCRIPTION: block-cipher algorithm SAFER (Secure And Fast Encryption +* Routine) in its four versions: SAFER K-64, SAFER K-128, +* SAFER SK-64 and SAFER SK-128. +* +* AUTHOR: Richard De Moliner ([email protected]) +* Signal and Information Processing Laboratory +* Swiss Federal Institute of Technology +* CH-8092 Zuerich, Switzerland +* +* DATE: September 9, 1995 +* +* CHANGE HISTORY: +* +*******************************************************************************/ + +#include <tomcrypt.h> + +#ifdef SAFER + +const struct ltc_cipher_descriptor + safer_k64_desc = { + "safer-k64", + 8, 8, 8, 8, SAFER_K64_DEFAULT_NOF_ROUNDS, + &safer_k64_setup, + &safer_ecb_encrypt, + &safer_ecb_decrypt, + &safer_k64_test, + &safer_done, + &safer_64_keysize, + NULL, NULL, NULL, NULL, NULL, NULL, NULL + }, + + safer_sk64_desc = { + "safer-sk64", + 9, 8, 8, 8, SAFER_SK64_DEFAULT_NOF_ROUNDS, + &safer_sk64_setup, + &safer_ecb_encrypt, + &safer_ecb_decrypt, + &safer_sk64_test, + &safer_done, + &safer_64_keysize, + NULL, NULL, NULL, NULL, NULL, NULL, NULL + }, + + safer_k128_desc = { + "safer-k128", + 10, 16, 16, 8, SAFER_K128_DEFAULT_NOF_ROUNDS, + &safer_k128_setup, + &safer_ecb_encrypt, + &safer_ecb_decrypt, + &safer_sk128_test, + &safer_done, + &safer_128_keysize, + NULL, NULL, NULL, NULL, NULL, NULL, NULL + }, + + safer_sk128_desc = { + "safer-sk128", + 11, 16, 16, 8, SAFER_SK128_DEFAULT_NOF_ROUNDS, + &safer_sk128_setup, + &safer_ecb_encrypt, + &safer_ecb_decrypt, + &safer_sk128_test, + &safer_done, + &safer_128_keysize, + NULL, NULL, NULL, NULL, NULL, NULL, NULL + }; + +/******************* Constants ************************************************/ +/* #define TAB_LEN 256 */ + +/******************* Assertions ***********************************************/ + +/******************* Macros ***************************************************/ +#define ROL8(x, n) ((unsigned char)((unsigned int)(x) << (n)\ + |(unsigned int)((x) & 0xFF) >> (8 - (n)))) +#define EXP(x) safer_ebox[(x) & 0xFF] +#define LOG(x) safer_lbox[(x) & 0xFF] +#define PHT(x, y) { y += x; x += y; } +#define IPHT(x, y) { x -= y; y -= x; } + +/******************* Types ****************************************************/ +extern const unsigned char safer_ebox[], safer_lbox[]; + +#ifdef LTC_CLEAN_STACK +static void _Safer_Expand_Userkey(const unsigned char *userkey_1, + const unsigned char *userkey_2, + unsigned int nof_rounds, + int strengthened, + safer_key_t key) +#else +static void Safer_Expand_Userkey(const unsigned char *userkey_1, + const unsigned char *userkey_2, + unsigned int nof_rounds, + int strengthened, + safer_key_t key) +#endif +{ unsigned int i, j, k; + unsigned char ka[SAFER_BLOCK_LEN + 1]; + unsigned char kb[SAFER_BLOCK_LEN + 1]; + + if (SAFER_MAX_NOF_ROUNDS < nof_rounds) + nof_rounds = SAFER_MAX_NOF_ROUNDS; + *key++ = (unsigned char)nof_rounds; + ka[SAFER_BLOCK_LEN] = (unsigned char)0; + kb[SAFER_BLOCK_LEN] = (unsigned char)0; + k = 0; + for (j = 0; j < SAFER_BLOCK_LEN; j++) { + ka[j] = ROL8(userkey_1[j], 5); + ka[SAFER_BLOCK_LEN] ^= ka[j]; + kb[j] = *key++ = userkey_2[j]; + kb[SAFER_BLOCK_LEN] ^= kb[j]; + } + for (i = 1; i <= nof_rounds; i++) { + for (j = 0; j < SAFER_BLOCK_LEN + 1; j++) { + ka[j] = ROL8(ka[j], 6); + kb[j] = ROL8(kb[j], 6); + } + if (strengthened) { + k = 2 * i - 1; + while (k >= (SAFER_BLOCK_LEN + 1)) { k -= SAFER_BLOCK_LEN + 1; } + } + for (j = 0; j < SAFER_BLOCK_LEN; j++) { + if (strengthened) { + *key++ = (ka[k] + + safer_ebox[(int)safer_ebox[(int)((18 * i + j + 1)&0xFF)]]) & 0xFF; + if (++k == (SAFER_BLOCK_LEN + 1)) { k = 0; } + } else { + *key++ = (ka[j] + safer_ebox[(int)safer_ebox[(int)((18 * i + j + 1)&0xFF)]]) & 0xFF; + } + } + if (strengthened) { + k = 2 * i; + while (k >= (SAFER_BLOCK_LEN + 1)) { k -= SAFER_BLOCK_LEN + 1; } + } + for (j = 0; j < SAFER_BLOCK_LEN; j++) { + if (strengthened) { + *key++ = (kb[k] + + safer_ebox[(int)safer_ebox[(int)((18 * i + j + 10)&0xFF)]]) & 0xFF; + if (++k == (SAFER_BLOCK_LEN + 1)) { k = 0; } + } else { + *key++ = (kb[j] + safer_ebox[(int)safer_ebox[(int)((18 * i + j + 10)&0xFF)]]) & 0xFF; + } + } + } + +#ifdef LTC_CLEAN_STACK + zeromem(ka, sizeof(ka)); + zeromem(kb, sizeof(kb)); +#endif +} + +#ifdef LTC_CLEAN_STACK +static void Safer_Expand_Userkey(const unsigned char *userkey_1, + const unsigned char *userkey_2, + unsigned int nof_rounds, + int strengthened, + safer_key_t key) +{ + _Safer_Expand_Userkey(userkey_1, userkey_2, nof_rounds, strengthened, key); + burn_stack(sizeof(unsigned char) * (2 * (SAFER_BLOCK_LEN + 1)) + sizeof(unsigned int)*2); +} +#endif + +int safer_k64_setup(const unsigned char *key, int keylen, int numrounds, symmetric_key *skey) +{ + LTC_ARGCHK(key != NULL); + LTC_ARGCHK(skey != NULL); + + if (numrounds != 0 && (numrounds < 6 || numrounds > SAFER_MAX_NOF_ROUNDS)) { + return CRYPT_INVALID_ROUNDS; + } + + if (keylen != 8) { + return CRYPT_INVALID_KEYSIZE; + } + + Safer_Expand_Userkey(key, key, (unsigned int)(numrounds != 0 ?numrounds:SAFER_K64_DEFAULT_NOF_ROUNDS), 0, skey->safer.key); + return CRYPT_OK; +} + +int safer_sk64_setup(const unsigned char *key, int keylen, int numrounds, symmetric_key *skey) +{ + LTC_ARGCHK(key != NULL); + LTC_ARGCHK(skey != NULL); + + if (numrounds != 0 && (numrounds < 6 || numrounds > SAFER_MAX_NOF_ROUNDS)) { + return CRYPT_INVALID_ROUNDS; + } + + if (keylen != 8) { + return CRYPT_INVALID_KEYSIZE; + } + + Safer_Expand_Userkey(key, key, (unsigned int)(numrounds != 0 ?numrounds:SAFER_SK64_DEFAULT_NOF_ROUNDS), 1, skey->safer.key); + return CRYPT_OK; +} + +int safer_k128_setup(const unsigned char *key, int keylen, int numrounds, symmetric_key *skey) +{ + LTC_ARGCHK(key != NULL); + LTC_ARGCHK(skey != NULL); + + if (numrounds != 0 && (numrounds < 6 || numrounds > SAFER_MAX_NOF_ROUNDS)) { + return CRYPT_INVALID_ROUNDS; + } + + if (keylen != 16) { + return CRYPT_INVALID_KEYSIZE; + } + + Safer_Expand_Userkey(key, key+8, (unsigned int)(numrounds != 0 ?numrounds:SAFER_K128_DEFAULT_NOF_ROUNDS), 0, skey->safer.key); + return CRYPT_OK; +} + +int safer_sk128_setup(const unsigned char *key, int keylen, int numrounds, symmetric_key *skey) +{ + LTC_ARGCHK(key != NULL); + LTC_ARGCHK(skey != NULL); + + if (numrounds != 0 && (numrounds < 6 || numrounds > SAFER_MAX_NOF_ROUNDS)) { + return CRYPT_INVALID_ROUNDS; + } + + if (keylen != 16) { + return CRYPT_INVALID_KEYSIZE; + } + + Safer_Expand_Userkey(key, key+8, (unsigned int)(numrounds != 0?numrounds:SAFER_SK128_DEFAULT_NOF_ROUNDS), 1, skey->safer.key); + return CRYPT_OK; +} + +#ifdef LTC_CLEAN_STACK +static void _safer_ecb_encrypt(const unsigned char *block_in, + unsigned char *block_out, + symmetric_key *skey) +#else +void safer_ecb_encrypt(const unsigned char *block_in, + unsigned char *block_out, + symmetric_key *skey) +#endif +{ unsigned char a, b, c, d, e, f, g, h, t; + unsigned int round; + unsigned char *key; + + LTC_ARGCHK(block_in != NULL); + LTC_ARGCHK(block_out != NULL); + LTC_ARGCHK(skey != NULL); + + key = skey->safer.key; + a = block_in[0]; b = block_in[1]; c = block_in[2]; d = block_in[3]; + e = block_in[4]; f = block_in[5]; g = block_in[6]; h = block_in[7]; + if (SAFER_MAX_NOF_ROUNDS < (round = *key)) round = SAFER_MAX_NOF_ROUNDS; + while(round-- > 0) + { + a ^= *++key; b += *++key; c += *++key; d ^= *++key; + e ^= *++key; f += *++key; g += *++key; h ^= *++key; + a = EXP(a) + *++key; b = LOG(b) ^ *++key; + c = LOG(c) ^ *++key; d = EXP(d) + *++key; + e = EXP(e) + *++key; f = LOG(f) ^ *++key; + g = LOG(g) ^ *++key; h = EXP(h) + *++key; + PHT(a, b); PHT(c, d); PHT(e, f); PHT(g, h); + PHT(a, c); PHT(e, g); PHT(b, d); PHT(f, h); + PHT(a, e); PHT(b, f); PHT(c, g); PHT(d, h); + t = b; b = e; e = c; c = t; t = d; d = f; f = g; g = t; + } + a ^= *++key; b += *++key; c += *++key; d ^= *++key; + e ^= *++key; f += *++key; g += *++key; h ^= *++key; + block_out[0] = a & 0xFF; block_out[1] = b & 0xFF; + block_out[2] = c & 0xFF; block_out[3] = d & 0xFF; + block_out[4] = e & 0xFF; block_out[5] = f & 0xFF; + block_out[6] = g & 0xFF; block_out[7] = h & 0xFF; +} + +#ifdef LTC_CLEAN_STACK +void safer_ecb_encrypt(const unsigned char *block_in, + unsigned char *block_out, + symmetric_key *skey) +{ + _safer_ecb_encrypt(block_in, block_out, skey); + burn_stack(sizeof(unsigned char) * 9 + sizeof(unsigned int) + sizeof(unsigned char *)); +} +#endif + +#ifdef LTC_CLEAN_STACK +static void _safer_ecb_decrypt(const unsigned char *block_in, + unsigned char *block_out, + symmetric_key *skey) +#else +void safer_ecb_decrypt(const unsigned char *block_in, + unsigned char *block_out, + symmetric_key *skey) +#endif +{ unsigned char a, b, c, d, e, f, g, h, t; + unsigned int round; + unsigned char *key; + + LTC_ARGCHK(block_in != NULL); + LTC_ARGCHK(block_out != NULL); + LTC_ARGCHK(skey != NULL); + + key = skey->safer.key; + a = block_in[0]; b = block_in[1]; c = block_in[2]; d = block_in[3]; + e = block_in[4]; f = block_in[5]; g = block_in[6]; h = block_in[7]; + if (SAFER_MAX_NOF_ROUNDS < (round = *key)) round = SAFER_MAX_NOF_ROUNDS; + key += SAFER_BLOCK_LEN * (1 + 2 * round); + h ^= *key; g -= *--key; f -= *--key; e ^= *--key; + d ^= *--key; c -= *--key; b -= *--key; a ^= *--key; + while (round--) + { + t = e; e = b; b = c; c = t; t = f; f = d; d = g; g = t; + IPHT(a, e); IPHT(b, f); IPHT(c, g); IPHT(d, h); + IPHT(a, c); IPHT(e, g); IPHT(b, d); IPHT(f, h); + IPHT(a, b); IPHT(c, d); IPHT(e, f); IPHT(g, h); + h -= *--key; g ^= *--key; f ^= *--key; e -= *--key; + d -= *--key; c ^= *--key; b ^= *--key; a -= *--key; + h = LOG(h) ^ *--key; g = EXP(g) - *--key; + f = EXP(f) - *--key; e = LOG(e) ^ *--key; + d = LOG(d) ^ *--key; c = EXP(c) - *--key; + b = EXP(b) - *--key; a = LOG(a) ^ *--key; + } + block_out[0] = a & 0xFF; block_out[1] = b & 0xFF; + block_out[2] = c & 0xFF; block_out[3] = d & 0xFF; + block_out[4] = e & 0xFF; block_out[5] = f & 0xFF; + block_out[6] = g & 0xFF; block_out[7] = h & 0xFF; +} + +#ifdef LTC_CLEAN_STACK +void safer_ecb_decrypt(const unsigned char *block_in, + unsigned char *block_out, + symmetric_key *skey) +{ + _safer_ecb_decrypt(block_in, block_out, skey); + burn_stack(sizeof(unsigned char) * 9 + sizeof(unsigned int) + sizeof(unsigned char *)); +} +#endif + +int safer_64_keysize(int *keysize) +{ + LTC_ARGCHK(keysize != NULL); + if (*keysize < 8) { + return CRYPT_INVALID_KEYSIZE; + } else { + *keysize = 8; + return CRYPT_OK; + } +} + +int safer_128_keysize(int *keysize) +{ + LTC_ARGCHK(keysize != NULL); + if (*keysize < 16) { + return CRYPT_INVALID_KEYSIZE; + } else { + *keysize = 16; + return CRYPT_OK; + } +} + +int safer_k64_test(void) +{ + #ifndef LTC_TEST + return CRYPT_NOP; + #else + static const unsigned char k64_pt[] = { 1, 2, 3, 4, 5, 6, 7, 8 }, + k64_key[] = { 8, 7, 6, 5, 4, 3, 2, 1 }, + k64_ct[] = { 200, 242, 156, 221, 135, 120, 62, 217 }; + + symmetric_key skey; + unsigned char buf[2][8]; + int err; + + /* test K64 */ + if ((err = safer_k64_setup(k64_key, 8, 6, &skey)) != CRYPT_OK) { + return err; + } + safer_ecb_encrypt(k64_pt, buf[0], &skey); + safer_ecb_decrypt(buf[0], buf[1], &skey); + + if (memcmp(buf[0], k64_ct, 8) != 0 || memcmp(buf[1], k64_pt, 8) != 0) { + return CRYPT_FAIL_TESTVECTOR; + } + + return CRYPT_OK; + #endif +} + + +int safer_sk64_test(void) +{ + #ifndef LTC_TEST + return CRYPT_NOP; + #else + static const unsigned char sk64_pt[] = { 1, 2, 3, 4, 5, 6, 7, 8 }, + sk64_key[] = { 1, 2, 3, 4, 5, 6, 7, 8 }, + sk64_ct[] = { 95, 206, 155, 162, 5, 132, 56, 199 }; + + symmetric_key skey; + unsigned char buf[2][8]; + int err, y; + + /* test SK64 */ + if ((err = safer_sk64_setup(sk64_key, 8, 6, &skey)) != CRYPT_OK) { + return err; + } + + safer_ecb_encrypt(sk64_pt, buf[0], &skey); + safer_ecb_decrypt(buf[0], buf[1], &skey); + + if (memcmp(buf[0], sk64_ct, 8) != 0 || memcmp(buf[1], sk64_pt, 8) != 0) { + return CRYPT_FAIL_TESTVECTOR; + } + + /* now see if we can encrypt all zero bytes 1000 times, decrypt and come back where we started */ + for (y = 0; y < 8; y++) buf[0][y] = 0; + for (y = 0; y < 1000; y++) safer_ecb_encrypt(buf[0], buf[0], &skey); + for (y = 0; y < 1000; y++) safer_ecb_decrypt(buf[0], buf[0], &skey); + for (y = 0; y < 8; y++) if (buf[0][y] != 0) return CRYPT_FAIL_TESTVECTOR; + + return CRYPT_OK; + #endif +} + +/** Terminate the context + @param skey The scheduled key +*/ +void safer_done(symmetric_key *skey) +{ +} + +int safer_sk128_test(void) +{ + #ifndef LTC_TEST + return CRYPT_NOP; + #else + static const unsigned char sk128_pt[] = { 1, 2, 3, 4, 5, 6, 7, 8 }, + sk128_key[] = { 1, 2, 3, 4, 5, 6, 7, 8, + 0, 0, 0, 0, 0, 0, 0, 0 }, + sk128_ct[] = { 255, 120, 17, 228, 179, 167, 46, 113 }; + + symmetric_key skey; + unsigned char buf[2][8]; + int err, y; + + /* test SK128 */ + if ((err = safer_sk128_setup(sk128_key, 16, 0, &skey)) != CRYPT_OK) { + return err; + } + safer_ecb_encrypt(sk128_pt, buf[0], &skey); + safer_ecb_decrypt(buf[0], buf[1], &skey); + + if (memcmp(buf[0], sk128_ct, 8) != 0 || memcmp(buf[1], sk128_pt, 8) != 0) { + return CRYPT_FAIL_TESTVECTOR; + } + + /* now see if we can encrypt all zero bytes 1000 times, decrypt and come back where we started */ + for (y = 0; y < 8; y++) buf[0][y] = 0; + for (y = 0; y < 1000; y++) safer_ecb_encrypt(buf[0], buf[0], &skey); + for (y = 0; y < 1000; y++) safer_ecb_decrypt(buf[0], buf[0], &skey); + for (y = 0; y < 8; y++) if (buf[0][y] != 0) return CRYPT_FAIL_TESTVECTOR; + return CRYPT_OK; + #endif +} + +#endif + + +