annotate libtommath/bn_mp_incr.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 1051e4eea25a
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
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1692
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1 #include "tommath_private.h"
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2 #ifdef BN_MP_INCR_C
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3 /* LibTomMath, multiple-precision integer library -- Tom St Denis */
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4 /* SPDX-License-Identifier: Unlicense */
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5
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6 /* Increment "a" by one like "a++". Changes input! */
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7 mp_err mp_incr(mp_int *a)
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8 {
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9 if (MP_IS_ZERO(a)) {
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10 mp_set(a,1uL);
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11 return MP_OKAY;
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12 } else if (a->sign == MP_NEG) {
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13 mp_err err;
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14 a->sign = MP_ZPOS;
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15 if ((err = mp_decr(a)) != MP_OKAY) {
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16 return err;
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17 }
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18 /* There is no -0 in LTM */
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19 if (!MP_IS_ZERO(a)) {
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20 a->sign = MP_NEG;
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21 }
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22 return MP_OKAY;
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23 } else if (a->dp[0] < MP_DIGIT_MAX) {
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24 a->dp[0]++;
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25 return MP_OKAY;
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26 } else {
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27 return mp_add_d(a, 1uL,a);
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28 }
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29 }
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30 #endif