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 ctr_setiv.c 15f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project CTR implementation, set IV, Tom St Denis 16f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project*/ 17f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 18f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project#ifdef LTC_CTR_MODE 19f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 20f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/** 21f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project Set an initial vector 22f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @param IV The initial vector 23f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @param len The length of the vector (in octets) 24f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @param ctr The CTR state 25f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project @return CRYPT_OK if successful 26f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project*/ 27f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Projectint ctr_setiv(const unsigned char *IV, unsigned long len, symmetric_CTR *ctr) 28f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project{ 29f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project int err; 30f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 31f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project LTC_ARGCHK(IV != NULL); 32f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project LTC_ARGCHK(ctr != NULL); 33f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 34f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project /* bad param? */ 35f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project if ((err = cipher_is_valid(ctr->cipher)) != CRYPT_OK) { 36f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project return err; 37f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 38f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 39f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project if (len != (unsigned long)ctr->blocklen) { 40f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project return CRYPT_INVALID_ARG; 41f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 42f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 43f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project /* set IV */ 44f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project XMEMCPY(ctr->ctr, IV, len); 45f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 46f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project /* force next block */ 47f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project ctr->padlen = 0; 48f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project return cipher_descriptor[ctr->cipher].ecb_encrypt(IV, ctr->pad, &ctr->key); 49f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project} 50f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 51f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project#endif 52f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 53f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 54f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/* $Source: /cvs/libtom/libtomcrypt/src/modes/ctr/ctr_setiv.c,v $ */ 55f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/* $Revision: 1.6 $ */ 56f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/* $Date: 2006/06/29 01:46:46 $ */ 57