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annotate libtomcrypt/src/encauth/ocb3/ocb3_int_ntz.c @ 1861:2b3a8026a6ce

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Add re-exec for server This allows ASLR to re-randomize the address space for every connection, preventing some vulnerabilities from being exploitable by repeated probing. Overhead (memory and time) is yet to be confirmed. At present this is only enabled on Linux. Other BSD platforms with fexecve() would probably also work though have not been tested.
author Matt Johnston <matt@ucc.asn.au>
date Sun, 30 Jan 2022 10:14:56 +0800
parents 6dba84798cd5
children
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6dba84798cd5 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: $Format:%ai$ */