dropbear: dbrandom.c annotate

annotate dbrandom.c @ 1788:1fc0012b9c38

Fix handling of replies to global requests (#112) The current code assumes that all global requests want / need a reply. This isn't always true and the request itself indicates if it wants a reply or not. It causes a specific problem with [email protected] messages. These are sent by OpenSSH after authentication to inform the client of potential other host keys for the host. This can be used to add a new type of host key or to rotate host keys. The initial information message from the server is sent as a global request, but with want_reply set to false. This means that the server doesn't expect an answer to this message. Instead the client needs to send a prove request as a reply if it wants to receive proof of ownership for the host keys. The bug doesn't cause any current problems with due to how OpenSSH treats receiving the failure message. It instead treats it as a keepalive message and further ignores it. Arguably this is a protocol violation though of Dropbear and it is only accidental that it doesn't cause a problem with OpenSSH. The bug was found when adding host keys support to libssh, which is more strict protocol wise and treats the unexpected failure message an error, also see https://gitlab.com/libssh/libssh-mirror/-/merge_requests/145 for more information. The fix here is to honor the want_reply flag in the global request and to only send a reply if the other side expects a reply.

author	Dirkjan Bussink <d.bussink@gmail.com>
date	Thu, 10 Dec 2020 16:13:13 +0100
parents	833bf9947603
children	3f4cdf839a1a

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) {
1701 6e5037ae2c1c Fix warning for unused prngd branch Matt Johnston <matt@ucc.asn.au> parents: 1698 diff changeset	56 int readfd = -1;
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
1757 517fb7b62438 Add some more variation to fuzzer random number generation Matt Johnston <matt@ucc.asn.au> parents: 1701 diff changeset	153 void fuzz_seed(const unsigned char* dat, unsigned int len) {
1774 833bf9947603 Fuzzing - get rid of "prefix" for streams Matt Johnston <matt@ucc.asn.au> parents: 1773 diff changeset	154 hash_state hs;
833bf9947603 Fuzzing - get rid of "prefix" for streams Matt Johnston <matt@ucc.asn.au> parents: 1773 diff changeset	155 sha1_init(&hs);
833bf9947603 Fuzzing - get rid of "prefix" for streams Matt Johnston <matt@ucc.asn.au> parents: 1773 diff changeset	156 sha1_process(&hs, "fuzzfuzzfuzz", strlen("fuzzfuzzfuzz"));
833bf9947603 Fuzzing - get rid of "prefix" for streams Matt Johnston <matt@ucc.asn.au> parents: 1773 diff changeset	157 sha1_process(&hs, dat, len);
833bf9947603 Fuzzing - get rid of "prefix" for streams Matt Johnston <matt@ucc.asn.au> parents: 1773 diff changeset	158 sha1_done(&hs, hashpool);
1347 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 @ 1788:1fc0012b9c38