diff options
Diffstat (limited to 'libtomcrypt/src/ciphers/rc2.c')
-rw-r--r-- | libtomcrypt/src/ciphers/rc2.c | 161 |
1 files changed, 108 insertions, 53 deletions
diff --git a/libtomcrypt/src/ciphers/rc2.c b/libtomcrypt/src/ciphers/rc2.c index 256f074..ebd8f88 100644 --- a/libtomcrypt/src/ciphers/rc2.c +++ b/libtomcrypt/src/ciphers/rc2.c @@ -5,8 +5,6 @@ * * The library is free for all purposes without any express * guarantee it works. - * - * Tom St Denis, tomstdenis@gmail.com, http://libtom.org */ /**********************************************************************\ * To commemorate the 1996 RSA Data Security Conference, the following * @@ -18,12 +16,12 @@ * Thanks to CodeView, SoftIce, and D86 for helping bring this code to * * the public. * \**********************************************************************/ -#include <tomcrypt.h> +#include "tomcrypt.h" /** @file rc2.c - Implementation of LTC_RC2 -*/ + Implementation of RC2 with fixed effective key length of 64bits +*/ #ifdef LTC_RC2 @@ -36,7 +34,7 @@ const struct ltc_cipher_descriptor rc2_desc = { &rc2_test, &rc2_done, &rc2_keysize, - NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL + NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL }; /* 256-entry permutation table, probably derived somehow from pi */ @@ -60,68 +58,87 @@ static const unsigned char permute[256] = { }; /** - Initialize the LTC_RC2 block cipher + Initialize the RC2 block cipher @param key The symmetric key you wish to pass @param keylen The key length in bytes + @param bits The effective key length in bits @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 rc2_setup(const unsigned char *key, int keylen, int num_rounds, symmetric_key *skey) +int rc2_setup_ex(const unsigned char *key, int keylen, int bits, int num_rounds, symmetric_key *skey) { unsigned *xkey = skey->rc2.xkey; unsigned char tmp[128]; unsigned T8, TM; - int i, bits; + int i; LTC_ARGCHK(key != NULL); LTC_ARGCHK(skey != NULL); - if (keylen < 8 || keylen > 128) { + if (keylen == 0 || keylen > 128 || bits > 1024) { return CRYPT_INVALID_KEYSIZE; } + if (bits == 0) { + bits = 1024; + } if (num_rounds != 0 && num_rounds != 16) { return CRYPT_INVALID_ROUNDS; } for (i = 0; i < keylen; i++) { - tmp[i] = key[i] & 255; + tmp[i] = key[i] & 255; } - /* Phase 1: Expand input key to 128 bytes */ - if (keylen < 128) { - for (i = keylen; i < 128; i++) { - tmp[i] = permute[(tmp[i - 1] + tmp[i - keylen]) & 255]; - } - } - - /* Phase 2 - reduce effective key size to "bits" */ - bits = keylen<<3; - T8 = (unsigned)(bits+7)>>3; - TM = (255 >> (unsigned)(7 & -bits)); - tmp[128 - T8] = permute[tmp[128 - T8] & TM]; - for (i = 127 - T8; i >= 0; i--) { - tmp[i] = permute[tmp[i + 1] ^ tmp[i + T8]]; - } + /* Phase 1: Expand input key to 128 bytes */ + if (keylen < 128) { + for (i = keylen; i < 128; i++) { + tmp[i] = permute[(tmp[i - 1] + tmp[i - keylen]) & 255]; + } + } - /* Phase 3 - copy to xkey in little-endian order */ - for (i = 0; i < 64; i++) { - xkey[i] = (unsigned)tmp[2*i] + ((unsigned)tmp[2*i+1] << 8); - } + /* Phase 2 - reduce effective key size to "bits" */ + T8 = (unsigned)(bits+7)>>3; + TM = (255 >> (unsigned)(7 & -bits)); + tmp[128 - T8] = permute[tmp[128 - T8] & TM]; + for (i = 127 - T8; i >= 0; i--) { + tmp[i] = permute[tmp[i + 1] ^ tmp[i + T8]]; + } + + /* Phase 3 - copy to xkey in little-endian order */ + for (i = 0; i < 64; i++) { + xkey[i] = (unsigned)tmp[2*i] + ((unsigned)tmp[2*i+1] << 8); + } #ifdef LTC_CLEAN_STACK - zeromem(tmp, sizeof(tmp)); + zeromem(tmp, sizeof(tmp)); #endif - - return CRYPT_OK; + + return CRYPT_OK; +} + +/** + Initialize the RC2 block cipher + + The effective key length is here always keylen * 8 + + @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 rc2_setup(const unsigned char *key, int keylen, int num_rounds, symmetric_key *skey) +{ + return rc2_setup_ex(key, keylen, keylen * 8, num_rounds, skey); } /**********************************************************************\ * Encrypt an 8-byte block of plaintext using the given key. * \**********************************************************************/ /** - Encrypts a block of text with LTC_RC2 + Encrypts a block of text with RC2 @param pt The input plaintext (8 bytes) @param ct The output ciphertext (8 bytes) @param skey The key as scheduled @@ -180,7 +197,7 @@ int rc2_ecb_encrypt( const unsigned char *pt, ct[5] = (unsigned char)(x54 >> 8); ct[6] = (unsigned char)x76; ct[7] = (unsigned char)(x76 >> 8); - + return CRYPT_OK; } @@ -199,10 +216,10 @@ int rc2_ecb_encrypt( const unsigned char *pt, * Decrypt an 8-byte block of ciphertext using the given key. * \**********************************************************************/ /** - Decrypts a block of text with LTC_RC2 + Decrypts a block of text with RC2 @param ct The input ciphertext (8 bytes) @param pt The output plaintext (8 bytes) - @param skey The key as scheduled + @param skey The key as scheduled @return CRYPT_OK if successful */ #ifdef LTC_CLEAN_STACK @@ -275,27 +292,56 @@ int rc2_ecb_decrypt( const unsigned char *ct, #endif /** - Performs a self-test of the LTC_RC2 block cipher + Performs a self-test of the RC2 block cipher @return CRYPT_OK if functional, CRYPT_NOP if self-test has been disabled */ int rc2_test(void) { #ifndef LTC_TEST return CRYPT_NOP; - #else + #else static const struct { - int keylen; + int keylen, bits; unsigned char key[16], pt[8], ct[8]; } tests[] = { - { 8, + { 8, 63, + { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, + { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, + { 0xeb, 0xb7, 0x73, 0xf9, 0x93, 0x27, 0x8e, 0xff } + }, + { 8, 64, + { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, + { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }, + { 0x27, 0x8b, 0x27, 0xe4, 0x2e, 0x2f, 0x0d, 0x49 } + }, + { 8, 64, { 0x30, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, { 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01 }, { 0x30, 0x64, 0x9e, 0xdf, 0x9b, 0xe7, 0xd2, 0xc2 } - }, - { 16, + { 1, 64, + { 0x88, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, + { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, + { 0x61, 0xa8, 0xa2, 0x44, 0xad, 0xac, 0xcc, 0xf0 } + }, + { 7, 64, + { 0x88, 0xbc, 0xa9, 0x0e, 0x90, 0x87, 0x5a, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, + { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, + { 0x6c, 0xcf, 0x43, 0x08, 0x97, 0x4c, 0x26, 0x7f } + }, + { 16, 64, + { 0x88, 0xbc, 0xa9, 0x0e, 0x90, 0x87, 0x5a, 0x7f, + 0x0f, 0x79, 0xc3, 0x84, 0x62, 0x7b, 0xaf, 0xb2 }, + { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, + { 0x1a, 0x80, 0x7d, 0x27, 0x2b, 0xbe, 0x5d, 0xb1 } + }, + { 16, 128, { 0x88, 0xbc, 0xa9, 0x0e, 0x90, 0x87, 0x5a, 0x7f, 0x0f, 0x79, 0xc3, 0x84, 0x62, 0x7b, 0xaf, 0xb2 }, { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, @@ -308,14 +354,22 @@ int rc2_test(void) for (x = 0; x < (int)(sizeof(tests) / sizeof(tests[0])); x++) { zeromem(tmp, sizeof(tmp)); - if ((err = rc2_setup(tests[x].key, tests[x].keylen, 0, &skey)) != CRYPT_OK) { - return err; + if (tests[x].bits == (tests[x].keylen * 8)) { + if ((err = rc2_setup(tests[x].key, tests[x].keylen, 0, &skey)) != CRYPT_OK) { + return err; + } + } + else { + if ((err = rc2_setup_ex(tests[x].key, tests[x].keylen, tests[x].bits, 0, &skey)) != CRYPT_OK) { + return err; + } } - + rc2_ecb_encrypt(tests[x].pt, tmp[0], &skey); rc2_ecb_decrypt(tmp[0], tmp[1], &skey); - - if (XMEMCMP(tmp[0], tests[x].ct, 8) != 0 || XMEMCMP(tmp[1], tests[x].pt, 8) != 0) { + + if (compare_testvector(tmp[0], 8, tests[x].ct, 8, "RC2 CT", x) || + compare_testvector(tmp[1], 8, tests[x].pt, 8, "RC2 PT", x)) { return CRYPT_FAIL_TESTVECTOR; } @@ -329,11 +383,12 @@ int rc2_test(void) #endif } -/** Terminate the context +/** Terminate the context @param skey The scheduled key */ void rc2_done(symmetric_key *skey) { + LTC_UNUSED_PARAM(skey); } /** @@ -344,7 +399,7 @@ void rc2_done(symmetric_key *skey) int rc2_keysize(int *keysize) { LTC_ARGCHK(keysize != NULL); - if (*keysize < 8) { + if (*keysize < 1) { return CRYPT_INVALID_KEYSIZE; } else if (*keysize > 128) { *keysize = 128; @@ -357,6 +412,6 @@ int rc2_keysize(int *keysize) -/* $Source$ */ -/* $Revision$ */ -/* $Date$ */ +/* ref: $Format:%D$ */ +/* git commit: $Format:%H$ */ +/* commit time: $Format:%ai$ */ |