1 /* LibTomCrypt, modular cryptographic library -- Tom St Denis 2 * 3 * LibTomCrypt is a library that provides various cryptographic 4 * algorithms in a highly modular and flexible manner. 5 * 6 * The library is free for all purposes without any express 7 * guarantee it works. 8 * 9 * Tom St Denis, tomstdenis (at) gmail.com, http://libtomcrypt.com 10 */ 11 #include "tomcrypt.h" 12 13 /** 14 @file ofb_setiv.c 15 OFB implementation, set IV, Tom St Denis 16 */ 17 18 #ifdef LTC_OFB_MODE 19 20 /** 21 Set an initial vector 22 @param IV The initial vector 23 @param len The length of the vector (in octets) 24 @param ofb The OFB state 25 @return CRYPT_OK if successful 26 */ 27 int ofb_setiv(const unsigned char *IV, unsigned long len, symmetric_OFB *ofb) 28 { 29 int err; 30 31 LTC_ARGCHK(IV != NULL); 32 LTC_ARGCHK(ofb != NULL); 33 34 if ((err = cipher_is_valid(ofb->cipher)) != CRYPT_OK) { 35 return err; 36 } 37 38 if (len != (unsigned long)ofb->blocklen) { 39 return CRYPT_INVALID_ARG; 40 } 41 42 /* force next block */ 43 ofb->padlen = 0; 44 return cipher_descriptor[ofb->cipher].ecb_encrypt(IV, ofb->IV, &ofb->key); 45 } 46 47 #endif 48 49 50 /* $Source: /cvs/libtom/libtomcrypt/src/modes/ofb/ofb_setiv.c,v $ */ 51 /* $Revision: 1.6 $ */ 52 /* $Date: 2006/06/29 01:51:34 $ */ 53