1f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/* LibTomCrypt, modular cryptographic library -- Tom St Denis 2f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * 3f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * LibTomCrypt is a library that provides various cryptographic 4f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * algorithms in a highly modular and flexible manner. 5f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * 6f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * The library is free for all purposes without any express 7f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * guarantee it works. 8f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * 9f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * Tom St Denis, tomstdenis@gmail.com, http://libtomcrypt.com 10f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project */ 11f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/**********************************************************************\ 12f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project* To commemorate the 1996 RSA Data Security Conference, the following * 13f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project* code is released into the public domain by its author. Prost! * 14f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project* * 15f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project* This cipher uses 16-bit words and little-endian byte ordering. * 16f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project* I wonder which processor it was optimized for? * 17f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project* * 18f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project* Thanks to CodeView, SoftIce, and D86 for helping bring this code to * 19f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project* the public. * 20f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project\**********************************************************************/ 21f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project#include <tomcrypt.h> 22f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 23f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/** 24f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @file rc2.c 25f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project Implementation of RC2 26f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project*/ 27f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 28f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project#ifdef RC2 29f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 30f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Projectconst struct ltc_cipher_descriptor rc2_desc = { 31f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project "rc2", 32f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 12, 8, 128, 8, 16, 33f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project &rc2_setup, 34f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project &rc2_ecb_encrypt, 35f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project &rc2_ecb_decrypt, 36f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project &rc2_test, 37f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project &rc2_done, 38f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project &rc2_keysize, 39f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL 40f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project}; 41f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 42f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/* 256-entry permutation table, probably derived somehow from pi */ 43f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Projectstatic const unsigned char permute[256] = { 44f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 217,120,249,196, 25,221,181,237, 40,233,253,121, 74,160,216,157, 45f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 198,126, 55,131, 43,118, 83,142, 98, 76,100,136, 68,139,251,162, 46f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 23,154, 89,245,135,179, 79, 19, 97, 69,109,141, 9,129,125, 50, 47f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 189,143, 64,235,134,183,123, 11,240,149, 33, 34, 92,107, 78,130, 48f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 84,214,101,147,206, 96,178, 28,115, 86,192, 20,167,140,241,220, 49f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 18,117,202, 31, 59,190,228,209, 66, 61,212, 48,163, 60,182, 38, 50f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 111,191, 14,218, 70,105, 7, 87, 39,242, 29,155,188,148, 67, 3, 51f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 248, 17,199,246,144,239, 62,231, 6,195,213, 47,200,102, 30,215, 52f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 8,232,234,222,128, 82,238,247,132,170,114,172, 53, 77,106, 42, 53f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 150, 26,210,113, 90, 21, 73,116, 75,159,208, 94, 4, 24,164,236, 54f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 194,224, 65,110, 15, 81,203,204, 36,145,175, 80,161,244,112, 57, 55f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 153,124, 58,133, 35,184,180,122,252, 2, 54, 91, 37, 85,151, 49, 56f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 45, 93,250,152,227,138,146,174, 5,223, 41, 16,103,108,186,201, 57f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 211, 0,230,207,225,158,168, 44, 99, 22, 1, 63, 88,226,137,169, 58f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 13, 56, 52, 27,171, 51,255,176,187, 72, 12, 95,185,177,205, 46, 59f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 197,243,219, 71,229,165,156,119, 10,166, 32,104,254,127,193,173 60f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project}; 61f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 62f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project /** 63f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project Initialize the RC2 block cipher 64f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @param key The symmetric key you wish to pass 65f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @param keylen The key length in bytes 66f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @param num_rounds The number of rounds desired (0 for default) 67f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @param skey The key in as scheduled by this function. 68f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @return CRYPT_OK if successful 69f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project */ 70f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Projectint rc2_setup(const unsigned char *key, int keylen, int num_rounds, symmetric_key *skey) 71f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project{ 72f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project unsigned *xkey = skey->rc2.xkey; 73f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project unsigned char tmp[128]; 74f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project unsigned T8, TM; 75f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project int i, bits; 76f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 77f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project LTC_ARGCHK(key != NULL); 78f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project LTC_ARGCHK(skey != NULL); 79f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 80f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project if (keylen < 8 || keylen > 128) { 81f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project return CRYPT_INVALID_KEYSIZE; 82f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 83f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 84f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project if (num_rounds != 0 && num_rounds != 16) { 85f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project return CRYPT_INVALID_ROUNDS; 86f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 87f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 88f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project for (i = 0; i < keylen; i++) { 89f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project tmp[i] = key[i] & 255; 90f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 91f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 92f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project /* Phase 1: Expand input key to 128 bytes */ 93f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project if (keylen < 128) { 94f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project for (i = keylen; i < 128; i++) { 95f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project tmp[i] = permute[(tmp[i - 1] + tmp[i - keylen]) & 255]; 96f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 97f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 98f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 99f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project /* Phase 2 - reduce effective key size to "bits" */ 100f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project bits = keylen<<3; 101f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project T8 = (unsigned)(bits+7)>>3; 102f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project TM = (255 >> (unsigned)(7 & -bits)); 103f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project tmp[128 - T8] = permute[tmp[128 - T8] & TM]; 104f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project for (i = 127 - T8; i >= 0; i--) { 105f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project tmp[i] = permute[tmp[i + 1] ^ tmp[i + T8]]; 106f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 107f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 108f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project /* Phase 3 - copy to xkey in little-endian order */ 109f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project for (i = 0; i < 64; i++) { 110f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project xkey[i] = (unsigned)tmp[2*i] + ((unsigned)tmp[2*i+1] << 8); 111f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 112f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 113f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project#ifdef LTC_CLEAN_STACK 114f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project zeromem(tmp, sizeof(tmp)); 115f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project#endif 116f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 117f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project return CRYPT_OK; 118f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project} 119f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 120f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/**********************************************************************\ 121f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project* Encrypt an 8-byte block of plaintext using the given key. * 122f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project\**********************************************************************/ 123f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/** 124f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project Encrypts a block of text with RC2 125f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @param pt The input plaintext (8 bytes) 126f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @param ct The output ciphertext (8 bytes) 127f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @param skey The key as scheduled 128f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @return CRYPT_OK if successful 129f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project*/ 130f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project#ifdef LTC_CLEAN_STACK 131f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Projectstatic int _rc2_ecb_encrypt( const unsigned char *pt, 132f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project unsigned char *ct, 133f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project symmetric_key *skey) 134f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project#else 135f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Projectint rc2_ecb_encrypt( const unsigned char *pt, 136f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project unsigned char *ct, 137f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project symmetric_key *skey) 138f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project#endif 139f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project{ 140f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project unsigned *xkey; 141f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project unsigned x76, x54, x32, x10, i; 142f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 143f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project LTC_ARGCHK(pt != NULL); 144f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project LTC_ARGCHK(ct != NULL); 145f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project LTC_ARGCHK(skey != NULL); 146f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 147f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project xkey = skey->rc2.xkey; 148f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 149f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x76 = ((unsigned)pt[7] << 8) + (unsigned)pt[6]; 150f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x54 = ((unsigned)pt[5] << 8) + (unsigned)pt[4]; 151f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x32 = ((unsigned)pt[3] << 8) + (unsigned)pt[2]; 152f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x10 = ((unsigned)pt[1] << 8) + (unsigned)pt[0]; 153f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 154f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project for (i = 0; i < 16; i++) { 155f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x10 = (x10 + (x32 & ~x76) + (x54 & x76) + xkey[4*i+0]) & 0xFFFF; 156f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x10 = ((x10 << 1) | (x10 >> 15)); 157f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 158f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x32 = (x32 + (x54 & ~x10) + (x76 & x10) + xkey[4*i+1]) & 0xFFFF; 159f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x32 = ((x32 << 2) | (x32 >> 14)); 160f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 161f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x54 = (x54 + (x76 & ~x32) + (x10 & x32) + xkey[4*i+2]) & 0xFFFF; 162f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x54 = ((x54 << 3) | (x54 >> 13)); 163f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 164f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x76 = (x76 + (x10 & ~x54) + (x32 & x54) + xkey[4*i+3]) & 0xFFFF; 165f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x76 = ((x76 << 5) | (x76 >> 11)); 166f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 167f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project if (i == 4 || i == 10) { 168f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x10 = (x10 + xkey[x76 & 63]) & 0xFFFF; 169f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x32 = (x32 + xkey[x10 & 63]) & 0xFFFF; 170f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x54 = (x54 + xkey[x32 & 63]) & 0xFFFF; 171f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x76 = (x76 + xkey[x54 & 63]) & 0xFFFF; 172f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 173f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 174f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 175f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project ct[0] = (unsigned char)x10; 176f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project ct[1] = (unsigned char)(x10 >> 8); 177f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project ct[2] = (unsigned char)x32; 178f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project ct[3] = (unsigned char)(x32 >> 8); 179f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project ct[4] = (unsigned char)x54; 180f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project ct[5] = (unsigned char)(x54 >> 8); 181f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project ct[6] = (unsigned char)x76; 182f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project ct[7] = (unsigned char)(x76 >> 8); 183f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 184f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project return CRYPT_OK; 185f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project} 186f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 187f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project#ifdef LTC_CLEAN_STACK 188f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Projectint rc2_ecb_encrypt( const unsigned char *pt, 189f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project unsigned char *ct, 190f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project symmetric_key *skey) 191f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project{ 192f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project int err = _rc2_ecb_encrypt(pt, ct, skey); 193f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project burn_stack(sizeof(unsigned *) + sizeof(unsigned) * 5); 194f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project return err; 195f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project} 196f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project#endif 197f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 198f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/**********************************************************************\ 199f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project* Decrypt an 8-byte block of ciphertext using the given key. * 200f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project\**********************************************************************/ 201f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/** 202f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project Decrypts a block of text with RC2 203f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @param ct The input ciphertext (8 bytes) 204f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @param pt The output plaintext (8 bytes) 205f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @param skey The key as scheduled 206f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @return CRYPT_OK if successful 207f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project*/ 208f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project#ifdef LTC_CLEAN_STACK 209f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Projectstatic int _rc2_ecb_decrypt( const unsigned char *ct, 210f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project unsigned char *pt, 211f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project symmetric_key *skey) 212f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project#else 213f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Projectint rc2_ecb_decrypt( const unsigned char *ct, 214f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project unsigned char *pt, 215f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project symmetric_key *skey) 216f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project#endif 217f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project{ 218f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project unsigned x76, x54, x32, x10; 219f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project unsigned *xkey; 220f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project int i; 221f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 222f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project LTC_ARGCHK(pt != NULL); 223f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project LTC_ARGCHK(ct != NULL); 224f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project LTC_ARGCHK(skey != NULL); 225f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 226f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project xkey = skey->rc2.xkey; 227f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 228f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x76 = ((unsigned)ct[7] << 8) + (unsigned)ct[6]; 229f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x54 = ((unsigned)ct[5] << 8) + (unsigned)ct[4]; 230f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x32 = ((unsigned)ct[3] << 8) + (unsigned)ct[2]; 231f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x10 = ((unsigned)ct[1] << 8) + (unsigned)ct[0]; 232f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 233f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project for (i = 15; i >= 0; i--) { 234f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project if (i == 4 || i == 10) { 235f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x76 = (x76 - xkey[x54 & 63]) & 0xFFFF; 236f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x54 = (x54 - xkey[x32 & 63]) & 0xFFFF; 237f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x32 = (x32 - xkey[x10 & 63]) & 0xFFFF; 238f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x10 = (x10 - xkey[x76 & 63]) & 0xFFFF; 239f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 240f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 241f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x76 = ((x76 << 11) | (x76 >> 5)); 242f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x76 = (x76 - ((x10 & ~x54) + (x32 & x54) + xkey[4*i+3])) & 0xFFFF; 243f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 244f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x54 = ((x54 << 13) | (x54 >> 3)); 245f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x54 = (x54 - ((x76 & ~x32) + (x10 & x32) + xkey[4*i+2])) & 0xFFFF; 246f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 247f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x32 = ((x32 << 14) | (x32 >> 2)); 248f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x32 = (x32 - ((x54 & ~x10) + (x76 & x10) + xkey[4*i+1])) & 0xFFFF; 249f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 250f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x10 = ((x10 << 15) | (x10 >> 1)); 251f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x10 = (x10 - ((x32 & ~x76) + (x54 & x76) + xkey[4*i+0])) & 0xFFFF; 252f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 253f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 254f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project pt[0] = (unsigned char)x10; 255f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project pt[1] = (unsigned char)(x10 >> 8); 256f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project pt[2] = (unsigned char)x32; 257f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project pt[3] = (unsigned char)(x32 >> 8); 258f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project pt[4] = (unsigned char)x54; 259f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project pt[5] = (unsigned char)(x54 >> 8); 260f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project pt[6] = (unsigned char)x76; 261f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project pt[7] = (unsigned char)(x76 >> 8); 262f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 263f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project return CRYPT_OK; 264f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project} 265f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 266f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project#ifdef LTC_CLEAN_STACK 267f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Projectint rc2_ecb_decrypt( const unsigned char *ct, 268f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project unsigned char *pt, 269f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project symmetric_key *skey) 270f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project{ 271f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project int err = _rc2_ecb_decrypt(ct, pt, skey); 272f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project burn_stack(sizeof(unsigned *) + sizeof(unsigned) * 4 + sizeof(int)); 273f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project return err; 274f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project} 275f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project#endif 276f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 277f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/** 278f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project Performs a self-test of the RC2 block cipher 279f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @return CRYPT_OK if functional, CRYPT_NOP if self-test has been disabled 280f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project*/ 281f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Projectint rc2_test(void) 282f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project{ 283f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project #ifndef LTC_TEST 284f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project return CRYPT_NOP; 285f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project #else 286f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project static const struct { 287f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project int keylen; 288f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project unsigned char key[16], pt[8], ct[8]; 289f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } tests[] = { 290f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 291f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project { 8, 292f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project { 0x30, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 293f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, 294f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project { 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01 }, 295f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project { 0x30, 0x64, 0x9e, 0xdf, 0x9b, 0xe7, 0xd2, 0xc2 } 296f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 297f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project }, 298f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project { 16, 299f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project { 0x88, 0xbc, 0xa9, 0x0e, 0x90, 0x87, 0x5a, 0x7f, 300f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 0x0f, 0x79, 0xc3, 0x84, 0x62, 0x7b, 0xaf, 0xb2 }, 301f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, 302f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project { 0x22, 0x69, 0x55, 0x2a, 0xb0, 0xf8, 0x5c, 0xa6 } 303f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 304f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project }; 305f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project int x, y, err; 306f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project symmetric_key skey; 307f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project unsigned char tmp[2][8]; 308f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 309f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project for (x = 0; x < (int)(sizeof(tests) / sizeof(tests[0])); x++) { 310f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project zeromem(tmp, sizeof(tmp)); 311f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project if ((err = rc2_setup(tests[x].key, tests[x].keylen, 0, &skey)) != CRYPT_OK) { 312f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project return err; 313f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 314f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 315f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project rc2_ecb_encrypt(tests[x].pt, tmp[0], &skey); 316f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project rc2_ecb_decrypt(tmp[0], tmp[1], &skey); 317f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 318f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project if (XMEMCMP(tmp[0], tests[x].ct, 8) != 0 || XMEMCMP(tmp[1], tests[x].pt, 8) != 0) { 319f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project return CRYPT_FAIL_TESTVECTOR; 320f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 321f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 322f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project /* now see if we can encrypt all zero bytes 1000 times, decrypt and come back where we started */ 323f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project for (y = 0; y < 8; y++) tmp[0][y] = 0; 324f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project for (y = 0; y < 1000; y++) rc2_ecb_encrypt(tmp[0], tmp[0], &skey); 325f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project for (y = 0; y < 1000; y++) rc2_ecb_decrypt(tmp[0], tmp[0], &skey); 326f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project for (y = 0; y < 8; y++) if (tmp[0][y] != 0) return CRYPT_FAIL_TESTVECTOR; 327f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 328f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project return CRYPT_OK; 329f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project #endif 330f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project} 331f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 332f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/** Terminate the context 333f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @param skey The scheduled key 334f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project*/ 335f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Projectvoid rc2_done(symmetric_key *skey) 336f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project{ 337f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project} 338f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 339f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/** 340f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project Gets suitable key size 341f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @param keysize [in/out] The length of the recommended key (in bytes). This function will store the suitable size back in this variable. 342f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @return CRYPT_OK if the input key size is acceptable. 343f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project*/ 344f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Projectint rc2_keysize(int *keysize) 345f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project{ 346f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project LTC_ARGCHK(keysize != NULL); 347f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project if (*keysize < 8) { 348f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project return CRYPT_INVALID_KEYSIZE; 349f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } else if (*keysize > 128) { 350f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project *keysize = 128; 351f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 352f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project return CRYPT_OK; 353f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project} 354f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 355f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project#endif 356f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 357f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 358f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 359f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 360f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/* $Source: /cvs/libtom/libtomcrypt/src/ciphers/rc2.c,v $ */ 361f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/* $Revision: 1.12 $ */ 362f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/* $Date: 2006/11/08 23:01:06 $ */ 363