annotate libtomcrypt/src/misc/burn_stack.c @ 1861:2b3a8026a6ce

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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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 #include "tomcrypt.h"
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10
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11 /**
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12 @file burn_stack.c
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13 Burn stack, Tom St Denis
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14 */
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16 /**
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17 Burn some stack memory
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18 @param len amount of stack to burn in bytes
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19 */
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20 void burn_stack(unsigned long len)
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21 {
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22 unsigned char buf[32];
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23 zeromem(buf, sizeof(buf));
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24 if (len > (unsigned long)sizeof(buf))
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25 burn_stack(len - sizeof(buf));
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26 }
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29
1471
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
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30 /* ref: $Format:%D$ */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
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31 /* git commit: $Format:%H$ */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
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32 /* commit time: $Format:%ai$ */