dropbear: dbrandom.c annotate

annotate dbrandom.c @ 1698:f966834f0f9c

Use Linux getrandom() to ensure random device is initialised Remove old code warning about random device being not ready, /dev/random isn't used by default anyway.

author	Matt Johnston <matt@ucc.asn.au>
date	Thu, 28 May 2020 22:50:41 +0800
parents	60fceff95858
children	6e5037ae2c1c

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"
1347 b28624698130 copy over some fuzzing code from AFL branch Matt Johnston <matt@ucc.asn.au> parents: 1274 diff changeset	30 #include "runopts.h"
4 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 */
1274 9da3e7b4fe55 add parentheses to macro Francois Perrad <francois.perrad@gadz.org> parents: 1096 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
1698 f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	52 /* Pass wantlen=0 to hash an entire file */
687 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,
1698 f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	55 unsigned int wantlen, int prngd) {
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	56 int readfd;
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	57 unsigned int readcount;
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	58 int ret = DROPBEAR_FAILURE;
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	59
1698 f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	60 if (prngd) {
1499 2d450c1056e3 options: Complete the transition to numeric toggles (`#if') Michael Witten <mfwitten@gmail.com> parents: 1459 diff changeset	61 #if DROPBEAR_USE_PRNGD
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	62 readfd = connect_unix(filename);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	63 #endif
1698 f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	64 } else {
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	65 readfd = open(filename, O_RDONLY);
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	66 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	67
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	68 if (readfd < 0) {
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	69 goto out;
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	70 }
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	71
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	72 readcount = 0;
1698 f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	73 while (wantlen == 0 \|\| readcount < wantlen) {
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	74 int readlen, wantread;
811 5de524aec047 limit how much we read from rt_cache etc Matt Johnston <matt@ucc.asn.au> parents: 737 diff changeset	75 unsigned char readbuf[4096];
1698 f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	76 if (wantlen == 0) {
694 c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	77 wantread = sizeof(readbuf);
1698 f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	78 } else {
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	79 wantread = MIN(sizeof(readbuf), wantlen-readcount);
694 c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	80 }
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	81
1499 2d450c1056e3 options: Complete the transition to numeric toggles (`#if') Michael Witten <mfwitten@gmail.com> parents: 1459 diff changeset	82 #if DROPBEAR_USE_PRNGD
1698 f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	83 if (prngd) {
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	84 char egdcmd[2];
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	85 egdcmd[0] = 0x02; /* blocking read */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	86 egdcmd[1] = (unsigned char)wantread;
1698 f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	87 if (write(readfd, egdcmd, 2) < 0) {
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	88 dropbear_exit("Can't send command to egd");
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	89 }
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	90 }
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	91 #endif
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	92 readlen = read(readfd, readbuf, wantread);
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	93 if (readlen <= 0) {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	94 if (readlen < 0 && errno == EINTR) {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	95 continue;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	96 }
1698 f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	97 if (readlen == 0 && wantlen == 0) {
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	98 /* whole file was read as requested */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	99 break;
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	100 }
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	101 goto out;
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	102 }
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	103 sha1_process(hs, readbuf, readlen);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	104 readcount += readlen;
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	105 }
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	106 ret = DROPBEAR_SUCCESS;
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	107 out:
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	108 close(readfd);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	109 return ret;
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	110 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	111
1459 06d52bcb8094 Pointer parameter could be declared as pointing to const Francois Perrad <francois.perrad@gadz.org> parents: 1401 diff changeset	112 void addrandom(const unsigned char * buf, unsigned int len)
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	113 {
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	114 hash_state hs;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	115
1558 2f64cb3d3007 - #if not #ifdef for DROPBEAR_FUZZ Matt Johnston <matt@ucc.asn.au> parents: 1511 diff changeset	116 #if DROPBEAR_FUZZ
1561 02b226c2675e clean some fuzzing conditionals Matt Johnston <matt@ucc.asn.au> parents: 1558 diff changeset	117 if (fuzz.fuzzing) {
1347 b28624698130 copy over some fuzzing code from AFL branch Matt Johnston <matt@ucc.asn.au> parents: 1274 diff changeset	118 return;
b28624698130 copy over some fuzzing code from AFL branch Matt Johnston <matt@ucc.asn.au> parents: 1274 diff changeset	119 }
b28624698130 copy over some fuzzing code from AFL branch Matt Johnston <matt@ucc.asn.au> parents: 1274 diff changeset	120 #endif
b28624698130 copy over some fuzzing code from AFL branch Matt Johnston <matt@ucc.asn.au> parents: 1274 diff changeset	121
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	122 /* hash in the new seed data */
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	123 sha1_init(&hs);
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	124 /* existing state (zeroes on startup) */
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	125 sha1_process(&hs, (void*)hashpool, sizeof(hashpool));
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	126
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	127 /* new */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	128 sha1_process(&hs, buf, len);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	129 sha1_done(&hs, hashpool);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	130 }
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	131
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	132 static void write_urandom()
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	133 {
1558 2f64cb3d3007 - #if not #ifdef for DROPBEAR_FUZZ Matt Johnston <matt@ucc.asn.au> parents: 1511 diff changeset	134 #if DROPBEAR_FUZZ
1561 02b226c2675e clean some fuzzing conditionals Matt Johnston <matt@ucc.asn.au> parents: 1558 diff changeset	135 if (fuzz.fuzzing) {
1347 b28624698130 copy over some fuzzing code from AFL branch Matt Johnston <matt@ucc.asn.au> parents: 1274 diff changeset	136 return;
b28624698130 copy over some fuzzing code from AFL branch Matt Johnston <matt@ucc.asn.au> parents: 1274 diff changeset	137 }
b28624698130 copy over some fuzzing code from AFL branch Matt Johnston <matt@ucc.asn.au> parents: 1274 diff changeset	138 #endif
1499 2d450c1056e3 options: Complete the transition to numeric toggles (`#if') Michael Witten <mfwitten@gmail.com> parents: 1459 diff changeset	139 #if !DROPBEAR_USE_PRNGD
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	140 /* This is opportunistic, don't worry about failure */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	141 unsigned char buf[INIT_SEED_SIZE];
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	142 FILE *f = fopen(DROPBEAR_URANDOM_DEV, "w");
737 7deb6fda1319 fix tabs Matt Johnston <matt@ucc.asn.au> parents: 735 diff changeset	143 if (!f) {
7deb6fda1319 fix tabs Matt Johnston <matt@ucc.asn.au> parents: 735 diff changeset	144 return;
7deb6fda1319 fix tabs Matt Johnston <matt@ucc.asn.au> parents: 735 diff changeset	145 }
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	146 genrandom(buf, sizeof(buf));
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	147 fwrite(buf, sizeof(buf), 1, f);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	148 fclose(f);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	149 #endif
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	150 }
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	151
1558 2f64cb3d3007 - #if not #ifdef for DROPBEAR_FUZZ Matt Johnston <matt@ucc.asn.au> parents: 1511 diff changeset	152 #if DROPBEAR_FUZZ
1369 ddfcadca3c4c fuzzer-pubkey Matt Johnston <matt@ucc.asn.au> parents: 1358 diff changeset	153 void fuzz_seed(void) {
1347 b28624698130 copy over some fuzzing code from AFL branch Matt Johnston <matt@ucc.asn.au> parents: 1274 diff changeset	154 hash_state hs;
b28624698130 copy over some fuzzing code from AFL branch Matt Johnston <matt@ucc.asn.au> parents: 1274 diff changeset	155 sha1_init(&hs);
b28624698130 copy over some fuzzing code from AFL branch Matt Johnston <matt@ucc.asn.au> parents: 1274 diff changeset	156 sha1_process(&hs, "fuzzfuzzfuzz", strlen("fuzzfuzzfuzz"));
b28624698130 copy over some fuzzing code from AFL branch Matt Johnston <matt@ucc.asn.au> parents: 1274 diff changeset	157 sha1_done(&hs, hashpool);
b28624698130 copy over some fuzzing code from AFL branch Matt Johnston <matt@ucc.asn.au> parents: 1274 diff changeset	158
b28624698130 copy over some fuzzing code from AFL branch Matt Johnston <matt@ucc.asn.au> parents: 1274 diff changeset	159 counter = 0;
b28624698130 copy over some fuzzing code from AFL branch Matt Johnston <matt@ucc.asn.au> parents: 1274 diff changeset	160 donerandinit = 1;
b28624698130 copy over some fuzzing code from AFL branch Matt Johnston <matt@ucc.asn.au> parents: 1274 diff changeset	161 }
1358 6b89eb92f872 glaring wrapfd problems fixed Matt Johnston <matt@ucc.asn.au> parents: 1357 diff changeset	162 #endif
1347 b28624698130 copy over some fuzzing code from AFL branch Matt Johnston <matt@ucc.asn.au> parents: 1274 diff changeset	163
1698 f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	164
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	165 #ifdef HAVE_GETRANDOM
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	166 /* Reads entropy seed with getrandom().
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	167 * May block if the kernel isn't ready.
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	168 * Return DROPBEAR_SUCCESS or DROPBEAR_FAILURE */
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	169 static int process_getrandom(hash_state *hs) {
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	170 char buf[INIT_SEED_SIZE];
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	171 ssize_t ret;
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	172
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	173 /* First try non-blocking so that we can warn about waiting */
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	174 ret = getrandom(buf, sizeof(buf), GRND_NONBLOCK);
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	175 if (ret == -1) {
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	176 if (errno == ENOSYS) {
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	177 /* Old kernel */
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	178 return DROPBEAR_FAILURE;
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	179 }
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	180 /* Other errors fall through to blocking getrandom() */
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	181 TRACE(("first getrandom() failed: %d %s", errno, strerror(errno)))
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	182 if (errno == EAGAIN) {
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	183 dropbear_log(LOG_WARNING, "Waiting for kernel randomness to be initialised...");
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	184 }
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	185 }
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	186
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	187 /* Wait blocking if needed. Loop in case we get EINTR */
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	188 while (ret != sizeof(buf)) {
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	189 ret = getrandom(buf, sizeof(buf), 0);
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	190
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	191 if (ret == sizeof(buf)) {
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	192 /* Success */
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	193 break;
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	194 }
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	195 if (ret == -1 && errno == EINTR) {
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	196 /* Try again. */
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	197 continue;
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	198 }
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	199 if (ret >= 0) {
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	200 TRACE(("Short read %zd from getrandom() shouldn't happen", ret))
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	201 /* Try again? */
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	202 continue;
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	203 }
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	204
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	205 /* Unexpected problem, fall back to /dev/urandom */
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	206 TRACE(("2nd getrandom() failed: %d %s", errno, strerror(errno)))
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	207 break;
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	208 }
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	209
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	210 if (ret == sizeof(buf)) {
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	211 /* Success, stir in the entropy */
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	212 sha1_process(hs, (void*)buf, sizeof(buf));
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	213 return DROPBEAR_SUCCESS;
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	214 }
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	215
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	216 return DROPBEAR_FAILURE;
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	217
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	218 }
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	219 #endif /* HAVE_GETRANDOM */
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	220
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	221 /* 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	222 * be called multiple times */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	223 void seedrandom() {
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 hash_state hs;
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	226
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	227 pid_t pid;
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	228 struct timeval tv;
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	229 clock_t clockval;
1698 f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	230 int urandom_seeded = 0;
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	231
1558 2f64cb3d3007 - #if not #ifdef for DROPBEAR_FUZZ Matt Johnston <matt@ucc.asn.au> parents: 1511 diff changeset	232 #if DROPBEAR_FUZZ
1561 02b226c2675e clean some fuzzing conditionals Matt Johnston <matt@ucc.asn.au> parents: 1558 diff changeset	233 if (fuzz.fuzzing) {
1347 b28624698130 copy over some fuzzing code from AFL branch Matt Johnston <matt@ucc.asn.au> parents: 1274 diff changeset	234 return;
b28624698130 copy over some fuzzing code from AFL branch Matt Johnston <matt@ucc.asn.au> parents: 1274 diff changeset	235 }
b28624698130 copy over some fuzzing code from AFL branch Matt Johnston <matt@ucc.asn.au> parents: 1274 diff changeset	236 #endif
b28624698130 copy over some fuzzing code from AFL branch Matt Johnston <matt@ucc.asn.au> parents: 1274 diff changeset	237
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	238 /* hash in the new seed data */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	239 sha1_init(&hs);
1347 b28624698130 copy over some fuzzing code from AFL branch Matt Johnston <matt@ucc.asn.au> parents: 1274 diff changeset	240
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	241 /* existing state */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	242 sha1_process(&hs, (void*)hashpool, sizeof(hashpool));
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	243
1698 f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	244 #ifdef HAVE_GETRANDOM
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	245 if (process_getrandom(&hs) == DROPBEAR_SUCCESS) {
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	246 urandom_seeded = 1;
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	247 }
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	248 #endif
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	249
1698 f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	250 if (!urandom_seeded) {
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	251 #if DROPBEAR_USE_PRNGD
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	252 if (process_file(&hs, DROPBEAR_PRNGD_SOCKET, INIT_SEED_SIZE, 1)
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	253 != DROPBEAR_SUCCESS) {
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	254 dropbear_exit("Failure reading random device %s",
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	255 DROPBEAR_PRNGD_SOCKET);
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	256 urandom_seeded = 1;
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	257 }
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	258 #else
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	259 /* non-blocking random source (probably /dev/urandom) */
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	260 if (process_file(&hs, DROPBEAR_URANDOM_DEV, INIT_SEED_SIZE, 0)
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	261 != DROPBEAR_SUCCESS) {
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	262 dropbear_exit("Failure reading random device %s",
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	263 DROPBEAR_URANDOM_DEV);
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	264 urandom_seeded = 1;
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	265 }
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	266 #endif
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	267 } /* urandom_seeded */
f966834f0f9c Use Linux getrandom() to ensure random device is initialised Matt Johnston <matt@ucc.asn.au> parents: 1596 diff changeset	268
694 c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	269 /* 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	270 * Add more here for other platforms */
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	271 #ifdef __linux__
688 650c41a4909a Add a few more files in /proc for Linux Matt Johnston <matt@ucc.asn.au> parents: 687 diff changeset	272 /* 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	273 * for even local attackers to reproduce */
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	274 process_file(&hs, "/proc/timer_list", 0, 0);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	275 /* Might help on systems with wireless */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	276 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	277
694 c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	278 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	279 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	280
811 5de524aec047 limit how much we read from rt_cache etc Matt Johnston <matt@ucc.asn.au> parents: 737 diff changeset	281 /* 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	282 * 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	283 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	284 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	285 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	286 /* 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	287 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	288 process_file(&hs, "/proc/vmstat", 0, 0);
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	289 #endif
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	290
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	291 pid = getpid();
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	292 sha1_process(&hs, (void*)&pid, sizeof(pid));
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	293
857 c19acba28590 use oldstyle comments Matt Johnston <matt@ucc.asn.au> parents: 855 diff changeset	294 /* gettimeofday() doesn't completely fill out struct timeval on
c19acba28590 use oldstyle comments Matt Johnston <matt@ucc.asn.au> parents: 855 diff changeset	295 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	296 memset(&tv, 0x0, sizeof(tv));
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	297 gettimeofday(&tv, NULL);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	298 sha1_process(&hs, (void*)&tv, sizeof(tv));
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	299
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	300 clockval = clock();
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	301 sha1_process(&hs, (void*)&clockval, sizeof(clockval));
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	302
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	303 /* 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	304 * be added to the hashpool - see runopts.c */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	305
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	306 sha1_done(&hs, hashpool);
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	307
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	308 counter = 0;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	309 donerandinit = 1;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	310
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	311 /* 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	312 * is running from inetd and gets new state each time */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	313 write_urandom();
272 3be7ae2e8dfa Only read /dev/random once when the program starts Matt Johnston <matt@ucc.asn.au> parents: 198 diff changeset	314 }
3be7ae2e8dfa Only read /dev/random once when the program starts Matt Johnston <matt@ucc.asn.au> parents: 198 diff changeset	315
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	316 /* return len bytes of pseudo-random data */
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	317 void genrandom(unsigned char* buf, unsigned int len) {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	318
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	319 hash_state hs;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	320 unsigned char hash[SHA1_HASH_SIZE];
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	321 unsigned int copylen;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	322
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	323 if (!donerandinit) {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	324 dropbear_exit("seedrandom not done");
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	325 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	326
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	327 while (len > 0) {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	328 sha1_init(&hs);
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	329 sha1_process(&hs, (void*)hashpool, sizeof(hashpool));
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	330 sha1_process(&hs, (void*)&counter, sizeof(counter));
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	331 sha1_done(&hs, hash);
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	332
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	333 counter++;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	334 if (counter > MAX_COUNTER) {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	335 seedrandom();
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	336 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	337
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	338 copylen = MIN(len, SHA1_HASH_SIZE);
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	339 memcpy(buf, hash, copylen);
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	340 len -= copylen;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	341 buf += copylen;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	342 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	343 m_burn(hash, sizeof(hash));
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	344 }
188 c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	345
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	346 /* 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	347 * 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	348 * 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	349 * 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	350 * */
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	351 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	352
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	353 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	354 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	355 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	356
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	357 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	358
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	359 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	360 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	361 len += 1;
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	362 }
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	363
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	364 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	365 do {
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	366 genrandom(randbuf, len);
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	367 /* 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	368 * MSB first.*/
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	369 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	370
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	371 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	372
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	373 /* 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	374 * 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	375 } 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	376 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	377 m_free(randbuf);
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	378 }

Mercurial > dropbear

annotate dbrandom.c @ 1698:f966834f0f9c