annotate src/encauth/eax/eax_decrypt.c @ 280:59400faa4b44 libtomcrypt-orig libtomcrypt-1.05

Re-import libtomcrypt 1.05 for cleaner propagating. From crypt-1.05.tar.bz2, SHA1 of 88250202bb51570dc64f7e8f1c943cda9479258f
author Matt Johnston <matt@ucc.asn.au>
date Wed, 08 Mar 2006 12:58:00 +0000
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children d5faf4814ddb
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59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
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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.org
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10 */
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11
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12 /**
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13 @file eax_decrypt.c
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14 EAX implementation, decrypt block, by Tom St Denis
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15 */
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16 #include "tomcrypt.h"
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17
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18 #ifdef EAX_MODE
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19
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20 /**
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21 Decrypt data with the EAX protocol
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22 @param eax The EAX state
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23 @param ct The ciphertext
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24 @param pt [out] The plaintext
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25 @param length The length (octets) of the ciphertext
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26 @return CRYPT_OK if successful
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27 */
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28 int eax_decrypt(eax_state *eax, const unsigned char *ct, unsigned char *pt,
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29 unsigned long length)
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30 {
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31 int err;
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32
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33 LTC_ARGCHK(eax != NULL);
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34 LTC_ARGCHK(pt != NULL);
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35 LTC_ARGCHK(ct != NULL);
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36
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37 /* omac ciphertext */
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38 if ((err = omac_process(&eax->ctomac, ct, length)) != CRYPT_OK) {
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39 return err;
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40 }
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41
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42 /* decrypt */
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43 return ctr_decrypt(ct, pt, length, &eax->ctr);
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44 }
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45
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46 #endif
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47
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48 /* $Source: /cvs/libtom/libtomcrypt/src/encauth/eax/eax_decrypt.c,v $ */
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49 /* $Revision: 1.3 $ */
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50 /* $Date: 2005/05/05 14:35:58 $ */