dropbear: dbrandom.c annotate

annotate dbrandom.c @ 1060:4c733310c21d nocircbuffer

reword comment for clarity

author	Matt Johnston <matt@ucc.asn.au>
date	Sun, 01 Mar 2015 23:26:42 +0800
parents	a1e79ffa5862
children	a9e4d66ffb2c

rev	line source
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	1 /*
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	2 * Dropbear - a SSH2 server
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	3 *
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	4 * Copyright (c) 2002,2003 Matt Johnston
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	5 * All rights reserved.
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	6 *
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	7 * Permission is hereby granted, free of charge, to any person obtaining a copy
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	8 * of this software and associated documentation files (the "Software"), to deal
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	9 * in the Software without restriction, including without limitation the rights
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	10 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	11 * copies of the Software, and to permit persons to whom the Software is
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	12 * furnished to do so, subject to the following conditions:
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	13 *
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	14 * The above copyright notice and this permission notice shall be included in
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	15 * all copies or substantial portions of the Software.
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	16 *
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	20 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	21 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	22 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	23 * SOFTWARE. */
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	24
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	25 #include "includes.h"
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	26 #include "buffer.h"
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	27 #include "dbutil.h"
188 c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	28 #include "bignum.h"
858 220f55d540ae rename random.h to dbrandom.h since some OSes have a system random.h Matt Johnston <matt@ucc.asn.au> parents: 857 diff changeset	29 #include "dbrandom.h"
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	30
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	31
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	32 /* this is used to generate unique output from the same hashpool */
272 3be7ae2e8dfa Only read /dev/random once when the program starts Matt Johnston <matt@ucc.asn.au> parents: 198 diff changeset	33 static uint32_t counter = 0;
298 7dad470ad4aa minor cleanups for some warnings Matt Johnston <matt@ucc.asn.au> parents: 272 diff changeset	34 /* the max value for the counter, so it won't integer overflow */
7dad470ad4aa minor cleanups for some warnings Matt Johnston <matt@ucc.asn.au> parents: 272 diff changeset	35 #define MAX_COUNTER 1<<30
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	36
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	37 static unsigned char hashpool[SHA1_HASH_SIZE] = {0};
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	38 static int donerandinit = 0;
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	39
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	40 #define INIT_SEED_SIZE 32 /* 256 bits */
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	41
149 ed9ca2a9705c Cleaned up the random code, use /dev/random by default, Matt Johnston <matt@ucc.asn.au> parents: 70 diff changeset	42 /* The basic setup is we read some data from /dev/(u)random or prngd and hash it
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	43 * into hashpool. To read data, we hash together current hashpool contents,
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	44 * and a counter. We feed more data in by hashing the current pool and new
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	45 * data into the pool.
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	46 *
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	47 * It is important to ensure that counter doesn't wrap around before we
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	48 * feed in new entropy.
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	49 *
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	50 */
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	51
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	52 /* Pass len=0 to hash an entire file */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	53 static int
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	54 process_file(hash_state hs, const char filename,
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	55 unsigned int len, int prngd)
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	56 {
185 5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	57 static int already_blocked = 0;
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	58 int readfd;
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	59 unsigned int readcount;
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	60 int ret = DROPBEAR_FAILURE;
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	61
149 ed9ca2a9705c Cleaned up the random code, use /dev/random by default, Matt Johnston <matt@ucc.asn.au> parents: 70 diff changeset	62 #ifdef DROPBEAR_PRNGD_SOCKET
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	63 if (prngd)
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	64 {
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	65 readfd = connect_unix(filename);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	66 }
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	67 else
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	68 #endif
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	69 {
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	70 readfd = open(filename, O_RDONLY);
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	71 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	72
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	73 if (readfd < 0) {
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	74 goto out;
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	75 }
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	76
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	77 readcount = 0;
694 c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	78 while (len == 0 \|\| readcount < len)
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	79 {
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	80 int readlen, wantread;
811 5de524aec047 limit how much we read from rt_cache etc Matt Johnston <matt@ucc.asn.au> parents: 737 diff changeset	81 unsigned char readbuf[4096];
855 04ede40a529a - Some fixes for old compilers like tru64 v4 from Daniel Richard G. Matt Johnston <matt@ucc.asn.au> parents: 843 diff changeset	82 if (!already_blocked && !prngd)
185 5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	83 {
843 3a9ec98808c3 Fix shadowed "ret" variable Matt Johnston <matt@ucc.asn.au> parents: 835 diff changeset	84 int res;
855 04ede40a529a - Some fixes for old compilers like tru64 v4 from Daniel Richard G. Matt Johnston <matt@ucc.asn.au> parents: 843 diff changeset	85 struct timeval timeout;
185 5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	86 fd_set read_fds;
5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	87
855 04ede40a529a - Some fixes for old compilers like tru64 v4 from Daniel Richard G. Matt Johnston <matt@ucc.asn.au> parents: 843 diff changeset	88 timeout.tv_sec = 2;
04ede40a529a - Some fixes for old compilers like tru64 v4 from Daniel Richard G. Matt Johnston <matt@ucc.asn.au> parents: 843 diff changeset	89 timeout.tv_usec = 0;
04ede40a529a - Some fixes for old compilers like tru64 v4 from Daniel Richard G. Matt Johnston <matt@ucc.asn.au> parents: 843 diff changeset	90
185 5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	91 FD_ZERO(&read_fds);
5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	92 FD_SET(readfd, &read_fds);
843 3a9ec98808c3 Fix shadowed "ret" variable Matt Johnston <matt@ucc.asn.au> parents: 835 diff changeset	93 res = select(readfd + 1, &read_fds, NULL, NULL, &timeout);
3a9ec98808c3 Fix shadowed "ret" variable Matt Johnston <matt@ucc.asn.au> parents: 835 diff changeset	94 if (res == 0)
185 5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	95 {
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	96 dropbear_log(LOG_WARNING, "Warning: Reading the randomness source '%s' seems to have blocked.\nYou may need to find a better entropy source.", filename);
185 5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	97 already_blocked = 1;
5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	98 }
5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	99 }
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	100
694 c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	101 if (len == 0)
c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	102 {
c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	103 wantread = sizeof(readbuf);
c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	104 }
c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	105 else
c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	106 {
c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	107 wantread = MIN(sizeof(readbuf), len-readcount);
c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	108 }
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	109
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	110 #ifdef DROPBEAR_PRNGD_SOCKET
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	111 if (prngd)
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	112 {
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	113 char egdcmd[2];
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	114 egdcmd[0] = 0x02; /* blocking read */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	115 egdcmd[1] = (unsigned char)wantread;
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	116 if (write(readfd, egdcmd, 2) < 0)
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	117 {
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	118 dropbear_exit("Can't send command to egd");
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	119 }
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	120 }
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	121 #endif
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	122
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	123 readlen = read(readfd, readbuf, wantread);
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	124 if (readlen <= 0) {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	125 if (readlen < 0 && errno == EINTR) {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	126 continue;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	127 }
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	128 if (readlen == 0 && len == 0)
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	129 {
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	130 /* whole file was read as requested */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	131 break;
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	132 }
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	133 goto out;
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	134 }
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	135 sha1_process(hs, readbuf, readlen);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	136 readcount += readlen;
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	137 }
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	138 ret = DROPBEAR_SUCCESS;
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	139 out:
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	140 close(readfd);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	141 return ret;
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	142 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	143
698 5f2d16d3e598 fix signedness error in prototype Matt Johnston <matt@ucc.asn.au> parents: 694 diff changeset	144 void addrandom(char * buf, unsigned int len)
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	145 {
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	146 hash_state hs;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	147
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	148 /* hash in the new seed data */
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	149 sha1_init(&hs);
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	150 /* existing state (zeroes on startup) */
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	151 sha1_process(&hs, (void*)hashpool, sizeof(hashpool));
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	152
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	153 /* new */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	154 sha1_process(&hs, buf, len);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	155 sha1_done(&hs, hashpool);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	156 }
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	157
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	158 static void write_urandom()
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	159 {
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	160 #ifndef DROPBEAR_PRNGD_SOCKET
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	161 /* This is opportunistic, don't worry about failure */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	162 unsigned char buf[INIT_SEED_SIZE];
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	163 FILE *f = fopen(DROPBEAR_URANDOM_DEV, "w");
737 7deb6fda1319 fix tabs Matt Johnston <matt@ucc.asn.au> parents: 735 diff changeset	164 if (!f) {
7deb6fda1319 fix tabs Matt Johnston <matt@ucc.asn.au> parents: 735 diff changeset	165 return;
7deb6fda1319 fix tabs Matt Johnston <matt@ucc.asn.au> parents: 735 diff changeset	166 }
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	167 genrandom(buf, sizeof(buf));
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	168 fwrite(buf, sizeof(buf), 1, f);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	169 fclose(f);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	170 #endif
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	171 }
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	172
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	173 /* Initialise the prng from /dev/urandom or prngd. This function can
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	174 * be called multiple times */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	175 void seedrandom() {
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	176
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	177 hash_state hs;
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	178
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	179 pid_t pid;
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	180 struct timeval tv;
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	181 clock_t clockval;
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	182
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	183 /* hash in the new seed data */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	184 sha1_init(&hs);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	185 /* existing state */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	186 sha1_process(&hs, (void*)hashpool, sizeof(hashpool));
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	187
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	188 #ifdef DROPBEAR_PRNGD_SOCKET
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	189 if (process_file(&hs, DROPBEAR_PRNGD_SOCKET, INIT_SEED_SIZE, 1)
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	190 != DROPBEAR_SUCCESS) {
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	191 dropbear_exit("Failure reading random device %s",
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	192 DROPBEAR_PRNGD_SOCKET);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	193 }
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	194 #else
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	195 /* non-blocking random source (probably /dev/urandom) */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	196 if (process_file(&hs, DROPBEAR_URANDOM_DEV, INIT_SEED_SIZE, 0)
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	197 != DROPBEAR_SUCCESS) {
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	198 dropbear_exit("Failure reading random device %s",
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	199 DROPBEAR_URANDOM_DEV);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	200 }
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	201 #endif
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	202
694 c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	203 /* A few other sources to fall back on.
c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	204 * Add more here for other platforms */
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	205 #ifdef __linux__
688 650c41a4909a Add a few more files in /proc for Linux Matt Johnston <matt@ucc.asn.au> parents: 687 diff changeset	206 /* Seems to be a reasonable source of entropy from timers. Possibly hard
650c41a4909a Add a few more files in /proc for Linux Matt Johnston <matt@ucc.asn.au> parents: 687 diff changeset	207 * for even local attackers to reproduce */
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	208 process_file(&hs, "/proc/timer_list", 0, 0);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	209 /* Might help on systems with wireless */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	210 process_file(&hs, "/proc/interrupts", 0, 0);
688 650c41a4909a Add a few more files in /proc for Linux Matt Johnston <matt@ucc.asn.au> parents: 687 diff changeset	211
694 c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	212 process_file(&hs, "/proc/loadavg", 0, 0);
c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	213 process_file(&hs, "/proc/sys/kernel/random/entropy_avail", 0, 0);
c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	214
811 5de524aec047 limit how much we read from rt_cache etc Matt Johnston <matt@ucc.asn.au> parents: 737 diff changeset	215 /* Mostly network visible but useful in some situations.
5de524aec047 limit how much we read from rt_cache etc Matt Johnston <matt@ucc.asn.au> parents: 737 diff changeset	216 * Limit size to avoid slowdowns on systems with lots of routes */
5de524aec047 limit how much we read from rt_cache etc Matt Johnston <matt@ucc.asn.au> parents: 737 diff changeset	217 process_file(&hs, "/proc/net/netstat", 4096, 0);
5de524aec047 limit how much we read from rt_cache etc Matt Johnston <matt@ucc.asn.au> parents: 737 diff changeset	218 process_file(&hs, "/proc/net/dev", 4096, 0);
5de524aec047 limit how much we read from rt_cache etc Matt Johnston <matt@ucc.asn.au> parents: 737 diff changeset	219 process_file(&hs, "/proc/net/tcp", 4096, 0);
688 650c41a4909a Add a few more files in /proc for Linux Matt Johnston <matt@ucc.asn.au> parents: 687 diff changeset	220 /* Also includes interface lo */
811 5de524aec047 limit how much we read from rt_cache etc Matt Johnston <matt@ucc.asn.au> parents: 737 diff changeset	221 process_file(&hs, "/proc/net/rt_cache", 4096, 0);
702 48e173a0c52b Include /proc/vmstat as another random source Matt Johnston <matt@ucc.asn.au> parents: 698 diff changeset	222 process_file(&hs, "/proc/vmstat", 0, 0);
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	223 #endif
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	224
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	225 pid = getpid();
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	226 sha1_process(&hs, (void*)&pid, sizeof(pid));
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	227
857 c19acba28590 use oldstyle comments Matt Johnston <matt@ucc.asn.au> parents: 855 diff changeset	228 /* gettimeofday() doesn't completely fill out struct timeval on
c19acba28590 use oldstyle comments Matt Johnston <matt@ucc.asn.au> parents: 855 diff changeset	229 OS X (10.8.3), avoid valgrind warnings by clearing it first */
714 84157e435c52 Make sure "struct timeval" is initialised on OS X to avoid valgrind warnings Matt Johnston <matt@ucc.asn.au> parents: 702 diff changeset	230 memset(&tv, 0x0, sizeof(tv));
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	231 gettimeofday(&tv, NULL);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	232 sha1_process(&hs, (void*)&tv, sizeof(tv));
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	233
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	234 clockval = clock();
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	235 sha1_process(&hs, (void*)&clockval, sizeof(clockval));
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	236
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	237 /* When a private key is read by the client or server it will
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	238 * be added to the hashpool - see runopts.c */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	239
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	240 sha1_done(&hs, hashpool);
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	241
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	242 counter = 0;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	243 donerandinit = 1;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	244
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	245 /* Feed it all back into /dev/urandom - this might help if Dropbear
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	246 * is running from inetd and gets new state each time */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	247 write_urandom();
272 3be7ae2e8dfa Only read /dev/random once when the program starts Matt Johnston <matt@ucc.asn.au> parents: 198 diff changeset	248 }
3be7ae2e8dfa Only read /dev/random once when the program starts Matt Johnston <matt@ucc.asn.au> parents: 198 diff changeset	249
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	250 /* return len bytes of pseudo-random data */
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	251 void genrandom(unsigned char* buf, unsigned int len) {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	252
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	253 hash_state hs;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	254 unsigned char hash[SHA1_HASH_SIZE];
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	255 unsigned int copylen;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	256
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	257 if (!donerandinit) {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	258 dropbear_exit("seedrandom not done");
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	259 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	260
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	261 while (len > 0) {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	262 sha1_init(&hs);
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	263 sha1_process(&hs, (void*)hashpool, sizeof(hashpool));
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	264 sha1_process(&hs, (void*)&counter, sizeof(counter));
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	265 sha1_done(&hs, hash);
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	266
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	267 counter++;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	268 if (counter > MAX_COUNTER) {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	269 seedrandom();
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	270 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	271
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	272 copylen = MIN(len, SHA1_HASH_SIZE);
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	273 memcpy(buf, hash, copylen);
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	274 len -= copylen;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	275 buf += copylen;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	276 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	277 m_burn(hash, sizeof(hash));
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	278 }
188 c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	279
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	280 /* Generates a random mp_int.
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	281 * max is a *mp_int specifying an upper bound.
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	282 * rand must be an initialised *mp_int for the result.
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	283 * the result rand satisfies: 0 < rand < max
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	284 * */
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	285 void gen_random_mpint(mp_int max, mp_int rand) {
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	286
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	287 unsigned char *randbuf = NULL;
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	288 unsigned int len = 0;
433 c216212001fc Fix for -pedantic -ansi compilation, change // to /*/, plus some signedness Matt Johnston <matt@ucc.asn.au>* parents: 405 diff changeset	289 const unsigned char masks[] = {0xff, 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f, 0x7f};
188 c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	290
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	291 const int size_bits = mp_count_bits(max);
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	292
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	293 len = size_bits / 8;
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	294 if ((size_bits % 8) != 0) {
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	295 len += 1;
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	296 }
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	297
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	298 randbuf = (unsigned char*)m_malloc(len);
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	299 do {
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	300 genrandom(randbuf, len);
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	301 /* Mask out the unrequired bits - mp_read_unsigned_bin expects
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	302 * MSB first.*/
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	303 randbuf[0] &= masks[size_bits % 8];
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	304
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	305 bytes_to_mp(rand, randbuf, len);
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	306
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	307 /* keep regenerating until we get one satisfying
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	308 * 0 < rand < max */
1013 a1e79ffa5862 Tighten validation of DH values. Odds of x==0 being generated are Matt Johnston <matt@ucc.asn.au> parents: 858 diff changeset	309 } while (!(mp_cmp(rand, max) == MP_LT && mp_cmp_d(rand, 0) == MP_GT));
188 c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	310 m_burn(randbuf, len);
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	311 m_free(randbuf);
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	312 }

Mercurial > dropbear

annotate dbrandom.c @ 1060:4c733310c21d nocircbuffer