Mercurial > dropbear
diff ofb_encrypt.c @ 3:7faae8f46238 libtomcrypt-orig
Branch renaming
author | Matt Johnston <matt@ucc.asn.au> |
---|---|
date | Mon, 31 May 2004 18:25:41 +0000 |
parents | |
children |
line wrap: on
line diff
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/ofb_encrypt.c Mon May 31 18:25:41 2004 +0000 @@ -0,0 +1,41 @@ +/* LibTomCrypt, modular cryptographic library -- Tom St Denis + * + * LibTomCrypt is a library that provides various cryptographic + * algorithms in a highly modular and flexible manner. + * + * The library is free for all purposes without any express + * guarantee it works. + * + * Tom St Denis, [email protected], http://libtomcrypt.org + */ +#include "mycrypt.h" + +#ifdef OFB + +int ofb_encrypt(const unsigned char *pt, unsigned char *ct, unsigned long len, symmetric_OFB *ofb) +{ + int err; + _ARGCHK(pt != NULL); + _ARGCHK(ct != NULL); + _ARGCHK(ofb != NULL); + if ((err = cipher_is_valid(ofb->cipher)) != CRYPT_OK) { + return err; + } + + /* is blocklen/padlen valid? */ + if (ofb->blocklen < 0 || ofb->blocklen > (int)sizeof(ofb->IV) || + ofb->padlen < 0 || ofb->padlen > (int)sizeof(ofb->IV)) { + return CRYPT_INVALID_ARG; + } + + while (len-- > 0) { + if (ofb->padlen == ofb->blocklen) { + cipher_descriptor[ofb->cipher].ecb_encrypt(ofb->IV, ofb->IV, &ofb->key); + ofb->padlen = 0; + } + *ct++ = *pt++ ^ ofb->IV[ofb->padlen++]; + } + return CRYPT_OK; +} + +#endif