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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 #include "mycrypt.h" |
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13 |
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14 #ifdef CTR |
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15 |
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16 int ctr_setiv(const unsigned char *IV, unsigned long len, symmetric_CTR *ctr) |
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17 { |
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18 int err; |
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19 |
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20 _ARGCHK(IV != NULL); |
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21 _ARGCHK(ctr != NULL); |
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22 |
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23 /* bad param? */ |
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24 if ((err = cipher_is_valid(ctr->cipher)) != CRYPT_OK) { |
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25 return err; |
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26 } |
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27 |
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28 if (len != (unsigned long)ctr->blocklen) { |
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29 return CRYPT_INVALID_ARG; |
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30 } |
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31 |
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32 /* set IV */ |
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33 memcpy(ctr->ctr, IV, len); |
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34 |
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35 /* force next block */ |
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36 ctr->padlen = 0; |
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37 cipher_descriptor[ctr->cipher].ecb_encrypt(IV, ctr->pad, &ctr->key); |
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38 |
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39 return CRYPT_OK; |
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40 } |
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41 |
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42 #endif |
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43 |
