Mercurial > dropbear
annotate libtomcrypt/src/encauth/ocb3/ocb3_int_ntz.c @ 1476:8305ebe45940
Put Dropbear config in a separate file
Patch out MECC DER
author | Matt Johnston <matt@ucc.asn.au> |
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date | Fri, 09 Feb 2018 23:35:07 +0800 |
parents | 6dba84798cd5 |
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rev | line source |
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1471
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Update to libtomcrypt 1.18.1, merged with Dropbear changes
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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 |
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10 /** |
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11 @file ocb3_int_ntz.c |
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12 OCB implementation, INTERNAL ONLY helper, by Tom St Denis |
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13 */ |
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14 #include "tomcrypt.h" |
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15 |
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16 #ifdef LTC_OCB3_MODE |
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17 |
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18 /** |
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19 Returns the number of leading zero bits [from lsb up] (internal function) |
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20 @param x The 32-bit value to observe |
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21 @return The number of bits [from the lsb up] that are zero |
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22 */ |
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23 int ocb3_int_ntz(unsigned long x) |
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24 { |
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25 int c; |
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26 x &= 0xFFFFFFFFUL; |
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27 c = 0; |
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28 while ((x & 1) == 0) { |
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29 ++c; |
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30 x >>= 1; |
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31 } |
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32 return c; |
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33 } |
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34 |
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35 #endif |
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36 |
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37 /* ref: $Format:%D$ */ |
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38 /* git commit: $Format:%H$ */ |
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39 /* commit time: $Format:%ai$ */ |