41 lines
1008 B
C
41 lines
1008 B
C
/* LibTomCrypt, modular cryptographic library -- Tom St Denis
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*
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* LibTomCrypt is a library that provides various cryptographic
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* algorithms in a highly modular and flexible manner.
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*
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* The library is free for all purposes without any express
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* guarantee it works.
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*
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* Tom St Denis, tomstdenis@iahu.ca, http://libtomcrypt.org
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*/
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#include "mycrypt.h"
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#ifdef OFB
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int ofb_start(int cipher, const unsigned char *IV, const unsigned char *key,
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int keylen, int num_rounds, symmetric_OFB *ofb)
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{
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int x, err;
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_ARGCHK(IV != NULL);
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_ARGCHK(key != NULL);
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_ARGCHK(ofb != NULL);
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if ((err = cipher_is_valid(cipher)) != CRYPT_OK) {
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return err;
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}
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/* copy details */
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ofb->cipher = cipher;
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ofb->blocklen = cipher_descriptor[cipher].block_length;
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for (x = 0; x < ofb->blocklen; x++) {
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ofb->IV[x] = IV[x];
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}
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/* init the cipher */
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ofb->padlen = ofb->blocklen;
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return cipher_descriptor[cipher].setup(key, keylen, num_rounds, &ofb->key);
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}
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#endif
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