Mercurial > dropbear
view libtomcrypt/src/ciphers/skipjack.c @ 1156:a8f4dade70e5
avoid getpass when not used
some systems (like android's bionic) do not provide getpass. you can
disable ENABLE_CLI_PASSWORD_AUTH & ENABLE_CLI_INTERACT_AUTH to avoid
its use (and rely on pubkey auth), but the link still fails because
the support file calls getpass. do not define this func if both of
those auth methods are not used.
author | Mike Frysinger <vapier@gentoo.org> |
---|---|
date | Wed, 21 Oct 2015 22:39:55 +0800 |
parents | 0cbe8f6dbf9e |
children | f849a5ca2efc |
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/* 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.com */ /** @file skipjack.c Skipjack Implementation by Tom St Denis */ #include "tomcrypt.h" #ifdef SKIPJACK const struct ltc_cipher_descriptor skipjack_desc = { "skipjack", 17, 10, 10, 8, 32, &skipjack_setup, &skipjack_ecb_encrypt, &skipjack_ecb_decrypt, &skipjack_test, &skipjack_done, &skipjack_keysize, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL }; static const unsigned char sbox[256] = { 0xa3,0xd7,0x09,0x83,0xf8,0x48,0xf6,0xf4,0xb3,0x21,0x15,0x78,0x99,0xb1,0xaf,0xf9, 0xe7,0x2d,0x4d,0x8a,0xce,0x4c,0xca,0x2e,0x52,0x95,0xd9,0x1e,0x4e,0x38,0x44,0x28, 0x0a,0xdf,0x02,0xa0,0x17,0xf1,0x60,0x68,0x12,0xb7,0x7a,0xc3,0xe9,0xfa,0x3d,0x53, 0x96,0x84,0x6b,0xba,0xf2,0x63,0x9a,0x19,0x7c,0xae,0xe5,0xf5,0xf7,0x16,0x6a,0xa2, 0x39,0xb6,0x7b,0x0f,0xc1,0x93,0x81,0x1b,0xee,0xb4,0x1a,0xea,0xd0,0x91,0x2f,0xb8, 0x55,0xb9,0xda,0x85,0x3f,0x41,0xbf,0xe0,0x5a,0x58,0x80,0x5f,0x66,0x0b,0xd8,0x90, 0x35,0xd5,0xc0,0xa7,0x33,0x06,0x65,0x69,0x45,0x00,0x94,0x56,0x6d,0x98,0x9b,0x76, 0x97,0xfc,0xb2,0xc2,0xb0,0xfe,0xdb,0x20,0xe1,0xeb,0xd6,0xe4,0xdd,0x47,0x4a,0x1d, 0x42,0xed,0x9e,0x6e,0x49,0x3c,0xcd,0x43,0x27,0xd2,0x07,0xd4,0xde,0xc7,0x67,0x18, 0x89,0xcb,0x30,0x1f,0x8d,0xc6,0x8f,0xaa,0xc8,0x74,0xdc,0xc9,0x5d,0x5c,0x31,0xa4, 0x70,0x88,0x61,0x2c,0x9f,0x0d,0x2b,0x87,0x50,0x82,0x54,0x64,0x26,0x7d,0x03,0x40, 0x34,0x4b,0x1c,0x73,0xd1,0xc4,0xfd,0x3b,0xcc,0xfb,0x7f,0xab,0xe6,0x3e,0x5b,0xa5, 0xad,0x04,0x23,0x9c,0x14,0x51,0x22,0xf0,0x29,0x79,0x71,0x7e,0xff,0x8c,0x0e,0xe2, 0x0c,0xef,0xbc,0x72,0x75,0x6f,0x37,0xa1,0xec,0xd3,0x8e,0x62,0x8b,0x86,0x10,0xe8, 0x08,0x77,0x11,0xbe,0x92,0x4f,0x24,0xc5,0x32,0x36,0x9d,0xcf,0xf3,0xa6,0xbb,0xac, 0x5e,0x6c,0xa9,0x13,0x57,0x25,0xb5,0xe3,0xbd,0xa8,0x3a,0x01,0x05,0x59,0x2a,0x46 }; /* simple x + 1 (mod 10) in one step. */ static const int keystep[] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 0 }; /* simple x - 1 (mod 10) in one step */ static const int ikeystep[] = { 9, 0, 1, 2, 3, 4, 5, 6, 7, 8 }; /** Initialize the Skipjack block cipher @param key The symmetric key you wish to pass @param keylen The key length in bytes @param num_rounds The number of rounds desired (0 for default) @param skey The key in as scheduled by this function. @return CRYPT_OK if successful */ int skipjack_setup(const unsigned char *key, int keylen, int num_rounds, symmetric_key *skey) { int x; LTC_ARGCHK(key != NULL); LTC_ARGCHK(skey != NULL); if (keylen != 10) { return CRYPT_INVALID_KEYSIZE; } if (num_rounds != 32 && num_rounds != 0) { return CRYPT_INVALID_ROUNDS; } /* make sure the key is in range for platforms where CHAR_BIT != 8 */ for (x = 0; x < 10; x++) { skey->skipjack.key[x] = key[x] & 255; } return CRYPT_OK; } #define RULE_A \ tmp = g_func(w1, &kp, skey->skipjack.key); \ w1 = tmp ^ w4 ^ x; \ w4 = w3; w3 = w2; \ w2 = tmp; #define RULE_B \ tmp = g_func(w1, &kp, skey->skipjack.key); \ tmp1 = w4; w4 = w3; \ w3 = w1 ^ w2 ^ x; \ w1 = tmp1; w2 = tmp; #define RULE_A1 \ tmp = w1 ^ w2 ^ x; \ w1 = ig_func(w2, &kp, skey->skipjack.key); \ w2 = w3; w3 = w4; w4 = tmp; #define RULE_B1 \ tmp = ig_func(w2, &kp, skey->skipjack.key); \ w2 = tmp ^ w3 ^ x; \ w3 = w4; w4 = w1; w1 = tmp; static unsigned g_func(unsigned w, int *kp, unsigned char *key) { unsigned char g1,g2; g1 = (w >> 8) & 255; g2 = w & 255; g1 ^= sbox[g2^key[*kp]]; *kp = keystep[*kp]; g2 ^= sbox[g1^key[*kp]]; *kp = keystep[*kp]; g1 ^= sbox[g2^key[*kp]]; *kp = keystep[*kp]; g2 ^= sbox[g1^key[*kp]]; *kp = keystep[*kp]; return ((unsigned)g1<<8)|(unsigned)g2; } static unsigned ig_func(unsigned w, int *kp, unsigned char *key) { unsigned char g1,g2; g1 = (w >> 8) & 255; g2 = w & 255; *kp = ikeystep[*kp]; g2 ^= sbox[g1^key[*kp]]; *kp = ikeystep[*kp]; g1 ^= sbox[g2^key[*kp]]; *kp = ikeystep[*kp]; g2 ^= sbox[g1^key[*kp]]; *kp = ikeystep[*kp]; g1 ^= sbox[g2^key[*kp]]; return ((unsigned)g1<<8)|(unsigned)g2; } /** Encrypts a block of text with Skipjack @param pt The input plaintext (8 bytes) @param ct The output ciphertext (8 bytes) @param skey The key as scheduled @return CRYPT_OK if successful */ #ifdef LTC_CLEAN_STACK static int _skipjack_ecb_encrypt(const unsigned char *pt, unsigned char *ct, symmetric_key *skey) #else int skipjack_ecb_encrypt(const unsigned char *pt, unsigned char *ct, symmetric_key *skey) #endif { unsigned w1,w2,w3,w4,tmp,tmp1; int x, kp; LTC_ARGCHK(pt != NULL); LTC_ARGCHK(ct != NULL); LTC_ARGCHK(skey != NULL); /* load block */ w1 = ((unsigned)pt[0]<<8)|pt[1]; w2 = ((unsigned)pt[2]<<8)|pt[3]; w3 = ((unsigned)pt[4]<<8)|pt[5]; w4 = ((unsigned)pt[6]<<8)|pt[7]; /* 8 rounds of RULE A */ for (x = 1, kp = 0; x < 9; x++) { RULE_A; } /* 8 rounds of RULE B */ for (; x < 17; x++) { RULE_B; } /* 8 rounds of RULE A */ for (; x < 25; x++) { RULE_A; } /* 8 rounds of RULE B */ for (; x < 33; x++) { RULE_B; } /* store block */ ct[0] = (w1>>8)&255; ct[1] = w1&255; ct[2] = (w2>>8)&255; ct[3] = w2&255; ct[4] = (w3>>8)&255; ct[5] = w3&255; ct[6] = (w4>>8)&255; ct[7] = w4&255; return CRYPT_OK; } #ifdef LTC_CLEAN_STACK int skipjack_ecb_encrypt(const unsigned char *pt, unsigned char *ct, symmetric_key *skey) { int err = _skipjack_ecb_encrypt(pt, ct, skey); burn_stack(sizeof(unsigned) * 8 + sizeof(int) * 2); return err; } #endif /** Decrypts a block of text with Skipjack @param ct The input ciphertext (8 bytes) @param pt The output plaintext (8 bytes) @param skey The key as scheduled @return CRYPT_OK if successful */ #ifdef LTC_CLEAN_STACK static int _skipjack_ecb_decrypt(const unsigned char *ct, unsigned char *pt, symmetric_key *skey) #else int skipjack_ecb_decrypt(const unsigned char *ct, unsigned char *pt, symmetric_key *skey) #endif { unsigned w1,w2,w3,w4,tmp; int x, kp; LTC_ARGCHK(pt != NULL); LTC_ARGCHK(ct != NULL); LTC_ARGCHK(skey != NULL); /* load block */ w1 = ((unsigned)ct[0]<<8)|ct[1]; w2 = ((unsigned)ct[2]<<8)|ct[3]; w3 = ((unsigned)ct[4]<<8)|ct[5]; w4 = ((unsigned)ct[6]<<8)|ct[7]; /* 8 rounds of RULE B^-1 Note the value "kp = 8" comes from "kp = (32 * 4) mod 10" where 32*4 is 128 which mod 10 is 8 */ for (x = 32, kp = 8; x > 24; x--) { RULE_B1; } /* 8 rounds of RULE A^-1 */ for (; x > 16; x--) { RULE_A1; } /* 8 rounds of RULE B^-1 */ for (; x > 8; x--) { RULE_B1; } /* 8 rounds of RULE A^-1 */ for (; x > 0; x--) { RULE_A1; } /* store block */ pt[0] = (w1>>8)&255; pt[1] = w1&255; pt[2] = (w2>>8)&255; pt[3] = w2&255; pt[4] = (w3>>8)&255; pt[5] = w3&255; pt[6] = (w4>>8)&255; pt[7] = w4&255; return CRYPT_OK; } #ifdef LTC_CLEAN_STACK int skipjack_ecb_decrypt(const unsigned char *ct, unsigned char *pt, symmetric_key *skey) { int err = _skipjack_ecb_decrypt(ct, pt, skey); burn_stack(sizeof(unsigned) * 7 + sizeof(int) * 2); return err; } #endif /** Performs a self-test of the Skipjack block cipher @return CRYPT_OK if functional, CRYPT_NOP if self-test has been disabled */ int skipjack_test(void) { #ifndef LTC_TEST return CRYPT_NOP; #else static const struct { unsigned char key[10], pt[8], ct[8]; } tests[] = { { { 0x00, 0x99, 0x88, 0x77, 0x66, 0x55, 0x44, 0x33, 0x22, 0x11 }, { 0x33, 0x22, 0x11, 0x00, 0xdd, 0xcc, 0xbb, 0xaa }, { 0x25, 0x87, 0xca, 0xe2, 0x7a, 0x12, 0xd3, 0x00 } } }; unsigned char buf[2][8]; int x, y, err; symmetric_key key; for (x = 0; x < (int)(sizeof(tests) / sizeof(tests[0])); x++) { /* setup key */ if ((err = skipjack_setup(tests[x].key, 10, 0, &key)) != CRYPT_OK) { return err; } /* encrypt and decrypt */ skipjack_ecb_encrypt(tests[x].pt, buf[0], &key); skipjack_ecb_decrypt(buf[0], buf[1], &key); /* compare */ if (XMEMCMP(buf[0], tests[x].ct, 8) != 0 || XMEMCMP(buf[1], tests[x].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++) skipjack_ecb_encrypt(buf[0], buf[0], &key); for (y = 0; y < 1000; y++) skipjack_ecb_decrypt(buf[0], buf[0], &key); 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 skipjack_done(symmetric_key *skey) { } /** Gets suitable key size @param keysize [in/out] The length of the recommended key (in bytes). This function will store the suitable size back in this variable. @return CRYPT_OK if the input key size is acceptable. */ int skipjack_keysize(int *keysize) { LTC_ARGCHK(keysize != NULL); if (*keysize < 10) { return CRYPT_INVALID_KEYSIZE; } else if (*keysize > 10) { *keysize = 10; } return CRYPT_OK; } #endif /* $Source: /cvs/libtom/libtomcrypt/src/ciphers/skipjack.c,v $ */ /* $Revision: 1.12 $ */ /* $Date: 2006/11/08 23:01:06 $ */