dropbear: dbrandom.c annotate

annotate dbrandom.c @ 1306:34e6127ef02e

merge fixes from PuTTY import.c toint() from misc.c (revids are from hggit conversion) changeset: 4620:60a336a6c85c user: Simon Tatham <[email protected]> date: Thu Feb 25 20:26:33 2016 +0000 files: import.c description: Fix potential segfaults in reading OpenSSH's ASN.1 key format. The length coming back from ber_read_id_len might have overflowed, so treat it as potentially negative. Also, while I'm here, accumulate it inside ber_read_id_len as an unsigned, so as to avoid undefined behaviour on integer overflow, and toint() it before return. Thanks to Hanno Böck for spotting this, with the aid of AFL. (cherry picked from commit 5b7833cd474a24ec098654dcba8cb9509f3bf2c1) Conflicts: import.c (cherry-picker's note: resolving the conflict involved removing an entire section of the original commit which fixed ECDSA code not present on this branch) changeset: 4619:9c6c638d98d8 user: Simon Tatham <[email protected]> date: Sun Jul 14 10:45:54 2013 +0000 files: import.c ssh.c sshdss.c sshpubk.c sshrsa.c description: Tighten up a lot of casts from unsigned to int which are read by one of the GET_32BIT macros and then used as length fields. Missing bounds checks against zero have been added, and also I've introduced a helper function toint() which casts from unsigned to int in such a way as to avoid C undefined behaviour, since I'm not sure I trust compilers any more to do the obviously sensible thing. [originally from svn r9918] changeset: 4618:3957829f24d3 user: Simon Tatham <[email protected]> date: Mon Jul 08 22:36:04 2013 +0000 files: import.c sshdss.c sshrsa.c description: Add an assortment of extra safety checks. [originally from svn r9896] changeset: 4617:2cddee0bce12 user: Jacob Nevins <[email protected]> date: Wed Dec 07 00:24:45 2005 +0000 files: import.c description: Institutional failure to memset() things pointed at rather than pointers. Things should now be zeroed and memory not leaked. Spotted by Brant Thomsen. [originally from svn r6476] changeset: 4616:24ac78a9c71d user: Simon Tatham <[email protected]> date: Wed Feb 11 13:58:27 2004 +0000 files: import.c description: Jacob's last-minute testing found a couple of trivial bugs in import.c, and my attempts to reproduce them in cmdgen found another one there :-) [originally from svn r3847] changeset: 4615:088d39a73db0 user: Simon Tatham <[email protected]> date: Thu Jan 22 18:52:49 2004 +0000 files: import.c description: Placate some gcc warnings. [originally from svn r3761] changeset: 4614:e4288bad4d93 parent: 1758:108b8924593d user: Simon Tatham <[email protected]> date: Fri Oct 03 21:21:23 2003 +0000 files: import.c description: My ASN.1 decoder returned wrong IDs for anything above 0x1E! Good job it's never had to yet. Ahem. [originally from svn r3479]

author	Matt Johnston <matt@ucc.asn.au>
date	Tue, 12 Jul 2016 23:00:01 +0800
parents	9da3e7b4fe55
children	750ec4ec4cbe b28624698130

rev	line source
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	1 /*
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	2 * Dropbear - a SSH2 server
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	3 *
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	4 * Copyright (c) 2002,2003 Matt Johnston
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	5 * All rights reserved.
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	6 *
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	7 * Permission is hereby granted, free of charge, to any person obtaining a copy
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	8 * of this software and associated documentation files (the "Software"), to deal
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	9 * in the Software without restriction, including without limitation the rights
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	10 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	11 * copies of the Software, and to permit persons to whom the Software is
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	12 * furnished to do so, subject to the following conditions:
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	13 *
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	14 * The above copyright notice and this permission notice shall be included in
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	15 * all copies or substantial portions of the Software.
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	16 *
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	20 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	21 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	22 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	23 * SOFTWARE. */
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	24
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	25 #include "includes.h"
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	26 #include "buffer.h"
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	27 #include "dbutil.h"
188 c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	28 #include "bignum.h"
858 220f55d540ae rename random.h to dbrandom.h since some OSes have a system random.h Matt Johnston <matt@ucc.asn.au> parents: 857 diff changeset	29 #include "dbrandom.h"
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	30
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	31
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	32 /* this is used to generate unique output from the same hashpool */
272 3be7ae2e8dfa Only read /dev/random once when the program starts Matt Johnston <matt@ucc.asn.au> parents: 198 diff changeset	33 static uint32_t counter = 0;
298 7dad470ad4aa minor cleanups for some warnings Matt Johnston <matt@ucc.asn.au> parents: 272 diff changeset	34 /* the max value for the counter, so it won't integer overflow */
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
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	52 /* Pass len=0 to hash an entire file */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	53 static int
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	54 process_file(hash_state hs, const char filename,
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	55 unsigned int len, int prngd)
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	56 {
185 5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	57 static int already_blocked = 0;
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	58 int readfd;
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	59 unsigned int readcount;
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	60 int ret = DROPBEAR_FAILURE;
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	61
149 ed9ca2a9705c Cleaned up the random code, use /dev/random by default, Matt Johnston <matt@ucc.asn.au> parents: 70 diff changeset	62 #ifdef DROPBEAR_PRNGD_SOCKET
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	63 if (prngd)
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	64 {
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	65 readfd = connect_unix(filename);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	66 }
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	67 else
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	68 #endif
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	69 {
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	70 readfd = open(filename, O_RDONLY);
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	71 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	72
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	73 if (readfd < 0) {
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	74 goto out;
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	75 }
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	76
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	77 readcount = 0;
694 c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	78 while (len == 0 \|\| readcount < len)
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	79 {
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	80 int readlen, wantread;
811 5de524aec047 limit how much we read from rt_cache etc Matt Johnston <matt@ucc.asn.au> parents: 737 diff changeset	81 unsigned char readbuf[4096];
855 04ede40a529a - Some fixes for old compilers like tru64 v4 from Daniel Richard G. Matt Johnston <matt@ucc.asn.au> parents: 843 diff changeset	82 if (!already_blocked && !prngd)
185 5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	83 {
843 3a9ec98808c3 Fix shadowed "ret" variable Matt Johnston <matt@ucc.asn.au> parents: 835 diff changeset	84 int res;
855 04ede40a529a - Some fixes for old compilers like tru64 v4 from Daniel Richard G. Matt Johnston <matt@ucc.asn.au> parents: 843 diff changeset	85 struct timeval timeout;
185 5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	86 fd_set read_fds;
5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	87
855 04ede40a529a - Some fixes for old compilers like tru64 v4 from Daniel Richard G. Matt Johnston <matt@ucc.asn.au> parents: 843 diff changeset	88 timeout.tv_sec = 2;
04ede40a529a - Some fixes for old compilers like tru64 v4 from Daniel Richard G. Matt Johnston <matt@ucc.asn.au> parents: 843 diff changeset	89 timeout.tv_usec = 0;
04ede40a529a - Some fixes for old compilers like tru64 v4 from Daniel Richard G. Matt Johnston <matt@ucc.asn.au> parents: 843 diff changeset	90
185 5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	91 FD_ZERO(&read_fds);
5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	92 FD_SET(readfd, &read_fds);
843 3a9ec98808c3 Fix shadowed "ret" variable Matt Johnston <matt@ucc.asn.au> parents: 835 diff changeset	93 res = select(readfd + 1, &read_fds, NULL, NULL, &timeout);
3a9ec98808c3 Fix shadowed "ret" variable Matt Johnston <matt@ucc.asn.au> parents: 835 diff changeset	94 if (res == 0)
185 5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	95 {
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	96 dropbear_log(LOG_WARNING, "Warning: Reading the randomness source '%s' seems to have blocked.\nYou may need to find a better entropy source.", filename);
185 5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	97 already_blocked = 1;
5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	98 }
5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	99 }
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	100
694 c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	101 if (len == 0)
c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	102 {
c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	103 wantread = sizeof(readbuf);
c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	104 }
c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	105 else
c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	106 {
c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	107 wantread = MIN(sizeof(readbuf), len-readcount);
c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	108 }
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	109
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	110 #ifdef DROPBEAR_PRNGD_SOCKET
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	111 if (prngd)
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	112 {
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	113 char egdcmd[2];
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	114 egdcmd[0] = 0x02; /* blocking read */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	115 egdcmd[1] = (unsigned char)wantread;
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	116 if (write(readfd, egdcmd, 2) < 0)
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	117 {
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	118 dropbear_exit("Can't send command to egd");
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	119 }
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	120 }
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	121 #endif
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	122
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	123 readlen = read(readfd, readbuf, wantread);
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	124 if (readlen <= 0) {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	125 if (readlen < 0 && errno == EINTR) {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	126 continue;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	127 }
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	128 if (readlen == 0 && len == 0)
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	129 {
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	130 /* whole file was read as requested */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	131 break;
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	132 }
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	133 goto out;
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	134 }
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	135 sha1_process(hs, readbuf, readlen);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	136 readcount += readlen;
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	137 }
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	138 ret = DROPBEAR_SUCCESS;
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	139 out:
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	140 close(readfd);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	141 return ret;
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	142 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	143
1096 a9e4d66ffb2c Turn addrandom()'s buf argument into unsigned char * Gaël PORTAY <gael.portay@gmail.com> parents: 1013 diff changeset	144 void addrandom(unsigned char * buf, unsigned int len)
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	145 {
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	146 hash_state hs;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	147
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	148 /* hash in the new seed data */
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	149 sha1_init(&hs);
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	150 /* existing state (zeroes on startup) */
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	151 sha1_process(&hs, (void*)hashpool, sizeof(hashpool));
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	152
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	153 /* new */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	154 sha1_process(&hs, buf, len);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	155 sha1_done(&hs, hashpool);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	156 }
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	157
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	158 static void write_urandom()
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	159 {
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	160 #ifndef DROPBEAR_PRNGD_SOCKET
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	161 /* This is opportunistic, don't worry about failure */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	162 unsigned char buf[INIT_SEED_SIZE];
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	163 FILE *f = fopen(DROPBEAR_URANDOM_DEV, "w");
737 7deb6fda1319 fix tabs Matt Johnston <matt@ucc.asn.au> parents: 735 diff changeset	164 if (!f) {
7deb6fda1319 fix tabs Matt Johnston <matt@ucc.asn.au> parents: 735 diff changeset	165 return;
7deb6fda1319 fix tabs Matt Johnston <matt@ucc.asn.au> parents: 735 diff changeset	166 }
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	167 genrandom(buf, sizeof(buf));
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	168 fwrite(buf, sizeof(buf), 1, f);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	169 fclose(f);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	170 #endif
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	171 }
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	172
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	173 /* Initialise the prng from /dev/urandom or prngd. This function can
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	174 * be called multiple times */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	175 void seedrandom() {
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	176
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	177 hash_state hs;
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	178
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	179 pid_t pid;
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	180 struct timeval tv;
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	181 clock_t clockval;
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	182
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	183 /* hash in the new seed data */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	184 sha1_init(&hs);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	185 /* existing state */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	186 sha1_process(&hs, (void*)hashpool, sizeof(hashpool));
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	187
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	188 #ifdef DROPBEAR_PRNGD_SOCKET
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	189 if (process_file(&hs, DROPBEAR_PRNGD_SOCKET, INIT_SEED_SIZE, 1)
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	190 != DROPBEAR_SUCCESS) {
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	191 dropbear_exit("Failure reading random device %s",
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	192 DROPBEAR_PRNGD_SOCKET);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	193 }
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	194 #else
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	195 /* non-blocking random source (probably /dev/urandom) */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	196 if (process_file(&hs, DROPBEAR_URANDOM_DEV, INIT_SEED_SIZE, 0)
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	197 != DROPBEAR_SUCCESS) {
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	198 dropbear_exit("Failure reading random device %s",
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	199 DROPBEAR_URANDOM_DEV);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	200 }
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	201 #endif
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	202
694 c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	203 /* A few other sources to fall back on.
c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	204 * Add more here for other platforms */
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	205 #ifdef __linux__
688 650c41a4909a Add a few more files in /proc for Linux Matt Johnston <matt@ucc.asn.au> parents: 687 diff changeset	206 /* Seems to be a reasonable source of entropy from timers. Possibly hard
650c41a4909a Add a few more files in /proc for Linux Matt Johnston <matt@ucc.asn.au> parents: 687 diff changeset	207 * for even local attackers to reproduce */
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	208 process_file(&hs, "/proc/timer_list", 0, 0);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	209 /* Might help on systems with wireless */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	210 process_file(&hs, "/proc/interrupts", 0, 0);
688 650c41a4909a Add a few more files in /proc for Linux Matt Johnston <matt@ucc.asn.au> parents: 687 diff changeset	211
694 c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	212 process_file(&hs, "/proc/loadavg", 0, 0);
c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	213 process_file(&hs, "/proc/sys/kernel/random/entropy_avail", 0, 0);
c85bb68e1db6 add loadavg and entropy_avail as sources Matt Johnston <matt@ucc.asn.au> parents: 689 diff changeset	214
811 5de524aec047 limit how much we read from rt_cache etc Matt Johnston <matt@ucc.asn.au> parents: 737 diff changeset	215 /* Mostly network visible but useful in some situations.
5de524aec047 limit how much we read from rt_cache etc Matt Johnston <matt@ucc.asn.au> parents: 737 diff changeset	216 * Limit size to avoid slowdowns on systems with lots of routes */
5de524aec047 limit how much we read from rt_cache etc Matt Johnston <matt@ucc.asn.au> parents: 737 diff changeset	217 process_file(&hs, "/proc/net/netstat", 4096, 0);
5de524aec047 limit how much we read from rt_cache etc Matt Johnston <matt@ucc.asn.au> parents: 737 diff changeset	218 process_file(&hs, "/proc/net/dev", 4096, 0);
5de524aec047 limit how much we read from rt_cache etc Matt Johnston <matt@ucc.asn.au> parents: 737 diff changeset	219 process_file(&hs, "/proc/net/tcp", 4096, 0);
688 650c41a4909a Add a few more files in /proc for Linux Matt Johnston <matt@ucc.asn.au> parents: 687 diff changeset	220 /* Also includes interface lo */
811 5de524aec047 limit how much we read from rt_cache etc Matt Johnston <matt@ucc.asn.au> parents: 737 diff changeset	221 process_file(&hs, "/proc/net/rt_cache", 4096, 0);
702 48e173a0c52b Include /proc/vmstat as another random source Matt Johnston <matt@ucc.asn.au> parents: 698 diff changeset	222 process_file(&hs, "/proc/vmstat", 0, 0);
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	223 #endif
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	224
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	225 pid = getpid();
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	226 sha1_process(&hs, (void*)&pid, sizeof(pid));
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	227
857 c19acba28590 use oldstyle comments Matt Johnston <matt@ucc.asn.au> parents: 855 diff changeset	228 /* gettimeofday() doesn't completely fill out struct timeval on
c19acba28590 use oldstyle comments Matt Johnston <matt@ucc.asn.au> parents: 855 diff changeset	229 OS X (10.8.3), avoid valgrind warnings by clearing it first */
714 84157e435c52 Make sure "struct timeval" is initialised on OS X to avoid valgrind warnings Matt Johnston <matt@ucc.asn.au> parents: 702 diff changeset	230 memset(&tv, 0x0, sizeof(tv));
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	231 gettimeofday(&tv, NULL);
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	232 sha1_process(&hs, (void*)&tv, sizeof(tv));
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	233
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	234 clockval = clock();
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	235 sha1_process(&hs, (void*)&clockval, sizeof(clockval));
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	236
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	237 /* When a private key is read by the client or server it will
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	238 * be added to the hashpool - see runopts.c */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	239
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	240 sha1_done(&hs, hashpool);
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	241
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	242 counter = 0;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	243 donerandinit = 1;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	244
687 167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	245 /* Feed it all back into /dev/urandom - this might help if Dropbear
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	246 * is running from inetd and gets new state each time */
167fdc091c05 Improve RNG seeding. Matt Johnston <matt@ucc.asn.au> parents: 602 diff changeset	247 write_urandom();
272 3be7ae2e8dfa Only read /dev/random once when the program starts Matt Johnston <matt@ucc.asn.au> parents: 198 diff changeset	248 }
3be7ae2e8dfa Only read /dev/random once when the program starts Matt Johnston <matt@ucc.asn.au> parents: 198 diff changeset	249
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	250 /* return len bytes of pseudo-random data */
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	251 void genrandom(unsigned char* buf, unsigned int len) {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	252
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	253 hash_state hs;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	254 unsigned char hash[SHA1_HASH_SIZE];
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	255 unsigned int copylen;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	256
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	257 if (!donerandinit) {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	258 dropbear_exit("seedrandom not done");
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	259 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	260
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	261 while (len > 0) {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	262 sha1_init(&hs);
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	263 sha1_process(&hs, (void*)hashpool, sizeof(hashpool));
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	264 sha1_process(&hs, (void*)&counter, sizeof(counter));
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	265 sha1_done(&hs, hash);
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	266
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	267 counter++;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	268 if (counter > MAX_COUNTER) {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	269 seedrandom();
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	270 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	271
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	272 copylen = MIN(len, SHA1_HASH_SIZE);
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	273 memcpy(buf, hash, copylen);
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	274 len -= copylen;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	275 buf += copylen;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	276 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	277 m_burn(hash, sizeof(hash));
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	278 }
188 c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	279
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	280 /* Generates a random mp_int.
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	281 * max is a *mp_int specifying an upper bound.
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	282 * rand must be an initialised *mp_int for the result.
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	283 * the result rand satisfies: 0 < rand < max
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	284 * */
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	285 void gen_random_mpint(mp_int max, mp_int rand) {
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	286
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	287 unsigned char *randbuf = NULL;
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	288 unsigned int len = 0;
433 c216212001fc Fix for -pedantic -ansi compilation, change // to /*/, plus some signedness Matt Johnston <matt@ucc.asn.au>* parents: 405 diff changeset	289 const unsigned char masks[] = {0xff, 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f, 0x7f};
188 c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	290
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	291 const int size_bits = mp_count_bits(max);
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	292
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	293 len = size_bits / 8;
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	294 if ((size_bits % 8) != 0) {
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	295 len += 1;
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	296 }
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	297
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	298 randbuf = (unsigned char*)m_malloc(len);
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	299 do {
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	300 genrandom(randbuf, len);
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	301 /* Mask out the unrequired bits - mp_read_unsigned_bin expects
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	302 * MSB first.*/
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	303 randbuf[0] &= masks[size_bits % 8];
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	304
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	305 bytes_to_mp(rand, randbuf, len);
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	306
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	307 /* keep regenerating until we get one satisfying
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	308 * 0 < rand < max */
1013 a1e79ffa5862 Tighten validation of DH values. Odds of x==0 being generated are Matt Johnston <matt@ucc.asn.au> parents: 858 diff changeset	309 } while (!(mp_cmp(rand, max) == MP_LT && mp_cmp_d(rand, 0) == MP_GT));
188 c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	310 m_burn(randbuf, len);
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	311 m_free(randbuf);
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	312 }

Mercurial > dropbear

annotate dbrandom.c @ 1306:34e6127ef02e