annotate libtomcrypt/src/modes/lrw/lrw_decrypt.c @ 556:ccdc4c6183c0

- Payload length doesn't include macsize.
author Matt Johnston <matt@ucc.asn.au>
date Sun, 26 Jul 2009 16:11:27 +0000
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1 /* LibTomCrypt, modular cryptographic library -- Tom St Denis
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2 *
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3 * LibTomCrypt is a library that provides various cryptographic
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4 * algorithms in a highly modular and flexible manner.
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5 *
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6 * The library is free for all purposes without any express
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7 * guarantee it works.
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8 *
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9 * Tom St Denis, [email protected], http://libtomcrypt.com
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10 */
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11 #include "tomcrypt.h"
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12
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13 /**
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14 @file lrw_decrypt.c
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15 LRW_MODE implementation, Decrypt blocks, Tom St Denis
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16 */
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17
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18 #ifdef LTC_LRW_MODE
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19
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20 /**
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21 LRW decrypt blocks
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22 @param ct The ciphertext
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23 @param pt [out] The plaintext
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24 @param len The length in octets, must be a multiple of 16
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25 @param lrw The LRW state
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26 */
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27 int lrw_decrypt(const unsigned char *ct, unsigned char *pt, unsigned long len, symmetric_LRW *lrw)
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28 {
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29 int err;
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30
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31 LTC_ARGCHK(pt != NULL);
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32 LTC_ARGCHK(ct != NULL);
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33 LTC_ARGCHK(lrw != NULL);
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34
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35 if ((err = cipher_is_valid(lrw->cipher)) != CRYPT_OK) {
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36 return err;
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37 }
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38
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39 if (cipher_descriptor[lrw->cipher].accel_lrw_decrypt != NULL) {
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40 return cipher_descriptor[lrw->cipher].accel_lrw_decrypt(ct, pt, len, lrw->IV, lrw->tweak, &lrw->key);
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41 }
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42
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43 return lrw_process(ct, pt, len, LRW_DECRYPT, lrw);
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44 }
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45
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46
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47 #endif
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48
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49 /* $Source: /cvs/libtom/libtomcrypt/src/modes/lrw/lrw_decrypt.c,v $ */
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50 /* $Revision: 1.8 $ */
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51 /* $Date: 2006/06/29 01:53:13 $ */