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#include "tomcrypt.h" 12f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 13f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/** 14f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @file f8_start.c 15f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project F8 implementation, start chain, Tom St Denis 16f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project*/ 17f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 18f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 19f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project#ifdef LTC_F8_MODE 20f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 21f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/** 22f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project Initialize an F8 context 23f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @param cipher The index of the cipher desired 24f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @param IV The initial vector 25f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @param key The secret key 26f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @param keylen The length of the secret key (octets) 27f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @param salt_key The salting key for the IV 28f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @param skeylen The length of the salting key (octets) 29f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @param num_rounds Number of rounds in the cipher desired (0 for default) 30f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @param f8 The F8 state to initialize 31f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @return CRYPT_OK if successful 32f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project*/ 33f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Projectint f8_start( int cipher, const unsigned char *IV, 34f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project const unsigned char *key, int keylen, 35f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project const unsigned char *salt_key, int skeylen, 36f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project int num_rounds, symmetric_F8 *f8) 37f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project{ 38f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project int x, err; 39f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project unsigned char tkey[MAXBLOCKSIZE]; 40f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 41f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project LTC_ARGCHK(IV != NULL); 42f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project LTC_ARGCHK(key != NULL); 43f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project LTC_ARGCHK(salt_key != NULL); 44f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project LTC_ARGCHK(f8 != NULL); 45f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 46f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project if ((err = cipher_is_valid(cipher)) != CRYPT_OK) { 47f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project return err; 48f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 49f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 50f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project#ifdef LTC_FAST 51f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project if (cipher_descriptor[cipher].block_length % sizeof(LTC_FAST_TYPE)) { 52f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project return CRYPT_INVALID_ARG; 53f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 54f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project#endif 55f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 56f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project /* copy details */ 57f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project f8->blockcnt = 0; 58f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project f8->cipher = cipher; 59f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project f8->blocklen = cipher_descriptor[cipher].block_length; 60f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project f8->padlen = f8->blocklen; 61f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 62f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project /* now get key ^ salt_key [extend salt_ket with 0x55 as required to match length] */ 63f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project zeromem(tkey, sizeof(tkey)); 64f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project for (x = 0; x < keylen && x < (int)sizeof(tkey); x++) { 65f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project tkey[x] = key[x]; 66f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 67f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project for (x = 0; x < skeylen && x < (int)sizeof(tkey); x++) { 68f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project tkey[x] ^= salt_key[x]; 69f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 70f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project for (; x < keylen && x < (int)sizeof(tkey); x++) { 71f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project tkey[x] ^= 0x55; 72f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 73f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 74f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project /* now encrypt with tkey[0..keylen-1] the IV and use that as the IV */ 75f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project if ((err = cipher_descriptor[cipher].setup(tkey, keylen, num_rounds, &f8->key)) != CRYPT_OK) { 76f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project return err; 77f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 78f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 79f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project /* encrypt IV */ 80f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project if ((err = cipher_descriptor[f8->cipher].ecb_encrypt(IV, f8->MIV, &f8->key)) != CRYPT_OK) { 81f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project cipher_descriptor[f8->cipher].done(&f8->key); 82f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project return err; 83f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 84f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project zeromem(tkey, sizeof(tkey)); 85f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project zeromem(f8->IV, sizeof(f8->IV)); 86f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 87f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project /* terminate this cipher */ 88f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project cipher_descriptor[f8->cipher].done(&f8->key); 89f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 90f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project /* init the cipher */ 91f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project return cipher_descriptor[cipher].setup(key, keylen, num_rounds, &f8->key); 92f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project} 93f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 94f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project#endif 95f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 96f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/* $Source: /cvs/libtom/libtomcrypt/src/modes/f8/f8_start.c,v $ */ 97f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/* $Revision: 1.7 $ */ 98f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/* $Date: 2006/11/05 01:36:43 $ */ 99