dropbear: libtommath/bn_mp

annotate libtommath/bn_mp_2expt.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

rev	line source
1655 f52919ffd3b1 update ltm to 1.1.0 and enable FIPS 186.4 compliant key-generation (#79) Steffen Jaeckel <s_jaeckel@gmx.de> parents: 1470 diff changeset	1 #include "tommath_private.h"
284 eed26cff980b propagate from branch 'au.asn.ucc.matt.ltm.dropbear' (head 6c790cad5a7fa866ad062cb3a0c279f7ba788583) Matt Johnston <matt@ucc.asn.au> parents: diff changeset	2 #ifdef BN_MP_2EXPT_C
1692 1051e4eea25a Update LibTomMath to 1.2.0 (#84) Steffen Jaeckel <s@jaeckel.eu> parents: 1655 diff changeset	3 /* LibTomMath, multiple-precision integer library -- Tom St Denis */
1051e4eea25a Update LibTomMath to 1.2.0 (#84) Steffen Jaeckel <s@jaeckel.eu> parents: 1655 diff changeset	4 /* SPDX-License-Identifier: Unlicense */
284 eed26cff980b propagate from branch 'au.asn.ucc.matt.ltm.dropbear' (head 6c790cad5a7fa866ad062cb3a0c279f7ba788583) Matt Johnston <matt@ucc.asn.au> parents: diff changeset	5
1655 f52919ffd3b1 update ltm to 1.1.0 and enable FIPS 186.4 compliant key-generation (#79) Steffen Jaeckel <s_jaeckel@gmx.de> parents: 1470 diff changeset	6 /* computes a = 2**b
284 eed26cff980b propagate from branch 'au.asn.ucc.matt.ltm.dropbear' (head 6c790cad5a7fa866ad062cb3a0c279f7ba788583) Matt Johnston <matt@ucc.asn.au> parents: diff changeset	7 *
eed26cff980b propagate from branch 'au.asn.ucc.matt.ltm.dropbear' (head 6c790cad5a7fa866ad062cb3a0c279f7ba788583) Matt Johnston <matt@ucc.asn.au> parents: diff changeset	8 * Simple algorithm which zeroes the int, grows it then just sets one bit
eed26cff980b propagate from branch 'au.asn.ucc.matt.ltm.dropbear' (head 6c790cad5a7fa866ad062cb3a0c279f7ba788583) Matt Johnston <matt@ucc.asn.au> parents: diff changeset	9 * as required.
eed26cff980b propagate from branch 'au.asn.ucc.matt.ltm.dropbear' (head 6c790cad5a7fa866ad062cb3a0c279f7ba788583) Matt Johnston <matt@ucc.asn.au> parents: diff changeset	10 */
1692 1051e4eea25a Update LibTomMath to 1.2.0 (#84) Steffen Jaeckel <s@jaeckel.eu> parents: 1655 diff changeset	11 mp_err mp_2expt(mp_int *a, int b)
284 eed26cff980b propagate from branch 'au.asn.ucc.matt.ltm.dropbear' (head 6c790cad5a7fa866ad062cb3a0c279f7ba788583) Matt Johnston <matt@ucc.asn.au> parents: diff changeset	12 {
1692 1051e4eea25a Update LibTomMath to 1.2.0 (#84) Steffen Jaeckel <s@jaeckel.eu> parents: 1655 diff changeset	13 mp_err err;
284 eed26cff980b propagate from branch 'au.asn.ucc.matt.ltm.dropbear' (head 6c790cad5a7fa866ad062cb3a0c279f7ba788583) Matt Johnston <matt@ucc.asn.au> parents: diff changeset	14
1655 f52919ffd3b1 update ltm to 1.1.0 and enable FIPS 186.4 compliant key-generation (#79) Steffen Jaeckel <s_jaeckel@gmx.de> parents: 1470 diff changeset	15 /* zero a as per default */
f52919ffd3b1 update ltm to 1.1.0 and enable FIPS 186.4 compliant key-generation (#79) Steffen Jaeckel <s_jaeckel@gmx.de> parents: 1470 diff changeset	16 mp_zero(a);
284 eed26cff980b propagate from branch 'au.asn.ucc.matt.ltm.dropbear' (head 6c790cad5a7fa866ad062cb3a0c279f7ba788583) Matt Johnston <matt@ucc.asn.au> parents: diff changeset	17
1655 f52919ffd3b1 update ltm to 1.1.0 and enable FIPS 186.4 compliant key-generation (#79) Steffen Jaeckel <s_jaeckel@gmx.de> parents: 1470 diff changeset	18 /* grow a to accomodate the single bit */
1692 1051e4eea25a Update LibTomMath to 1.2.0 (#84) Steffen Jaeckel <s@jaeckel.eu> parents: 1655 diff changeset	19 if ((err = mp_grow(a, (b / MP_DIGIT_BIT) + 1)) != MP_OKAY) {
1051e4eea25a Update LibTomMath to 1.2.0 (#84) Steffen Jaeckel <s@jaeckel.eu> parents: 1655 diff changeset	20 return err;
1655 f52919ffd3b1 update ltm to 1.1.0 and enable FIPS 186.4 compliant key-generation (#79) Steffen Jaeckel <s_jaeckel@gmx.de> parents: 1470 diff changeset	21 }
284 eed26cff980b propagate from branch 'au.asn.ucc.matt.ltm.dropbear' (head 6c790cad5a7fa866ad062cb3a0c279f7ba788583) Matt Johnston <matt@ucc.asn.au> parents: diff changeset	22
1655 f52919ffd3b1 update ltm to 1.1.0 and enable FIPS 186.4 compliant key-generation (#79) Steffen Jaeckel <s_jaeckel@gmx.de> parents: 1470 diff changeset	23 /* set the used count of where the bit will go */
1692 1051e4eea25a Update LibTomMath to 1.2.0 (#84) Steffen Jaeckel <s@jaeckel.eu> parents: 1655 diff changeset	24 a->used = (b / MP_DIGIT_BIT) + 1;
284 eed26cff980b propagate from branch 'au.asn.ucc.matt.ltm.dropbear' (head 6c790cad5a7fa866ad062cb3a0c279f7ba788583) Matt Johnston <matt@ucc.asn.au> parents: diff changeset	25
1655 f52919ffd3b1 update ltm to 1.1.0 and enable FIPS 186.4 compliant key-generation (#79) Steffen Jaeckel <s_jaeckel@gmx.de> parents: 1470 diff changeset	26 /* put the single bit in its place */
1692 1051e4eea25a Update LibTomMath to 1.2.0 (#84) Steffen Jaeckel <s@jaeckel.eu> parents: 1655 diff changeset	27 a->dp[b / MP_DIGIT_BIT] = (mp_digit)1 << (mp_digit)(b % MP_DIGIT_BIT);
284 eed26cff980b propagate from branch 'au.asn.ucc.matt.ltm.dropbear' (head 6c790cad5a7fa866ad062cb3a0c279f7ba788583) Matt Johnston <matt@ucc.asn.au> parents: diff changeset	28
1655 f52919ffd3b1 update ltm to 1.1.0 and enable FIPS 186.4 compliant key-generation (#79) Steffen Jaeckel <s_jaeckel@gmx.de> parents: 1470 diff changeset	29 return MP_OKAY;
284 eed26cff980b propagate from branch 'au.asn.ucc.matt.ltm.dropbear' (head 6c790cad5a7fa866ad062cb3a0c279f7ba788583) Matt Johnston <matt@ucc.asn.au> parents: diff changeset	30 }
eed26cff980b propagate from branch 'au.asn.ucc.matt.ltm.dropbear' (head 6c790cad5a7fa866ad062cb3a0c279f7ba788583) Matt Johnston <matt@ucc.asn.au> parents: diff changeset	31 #endif

Mercurial > dropbear

annotate libtommath/bn_mp_2expt.c @ 1861:2b3a8026a6ce