dropbear: random.c annotate

annotate random.c @ 447:278805938dcf

Patch from Nicolai Ehemann to try binding before going to the background, so that if it exits early (because something's already listening etc) then it will return an exitcode of 1.

author	Matt Johnston <matt@ucc.asn.au>
date	Thu, 19 Jul 2007 15:54:18 +0000
parents	2cd2edfa11ee
children	c1e9c81d1d27 76097ec1a29a

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"
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	29
198 65585699d980 * add a "label" argument to printhex() Matt Johnston <matt@ucc.asn.au> parents: 189 diff changeset	30 static int donerandinit = 0;
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 */
7dad470ad4aa minor cleanups for some warnings Matt Johnston <matt@ucc.asn.au> parents: 272 diff changeset	35 #define MAX_COUNTER 1<<30
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	36
198 65585699d980 * add a "label" argument to printhex() Matt Johnston <matt@ucc.asn.au> parents: 189 diff changeset	37 static unsigned char hashpool[SHA1_HASH_SIZE];
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	38
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	39 #define INIT_SEED_SIZE 32 /* 256 bits */
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	40
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	41 static void readrand(unsigned char* buf, unsigned int buflen);
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	42
149 ed9ca2a9705c Cleaned up the random code, use /dev/random by default, Matt Johnston <matt@ucc.asn.au> parents: 70 diff changeset	43 /* 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	44 * 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	45 * 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	46 * data into the pool.
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	47 *
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	48 * 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	49 * feed in new entropy.
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 */
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	52
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	53 static void readrand(unsigned char* buf, unsigned int buflen) {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	54
185 5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	55 static int already_blocked = 0;
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	56 int readfd;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	57 unsigned int readpos;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	58 int readlen;
149 ed9ca2a9705c Cleaned up the random code, use /dev/random by default, Matt Johnston <matt@ucc.asn.au> parents: 70 diff changeset	59 #ifdef DROPBEAR_PRNGD_SOCKET
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	60 struct sockaddr_un egdsock;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	61 char egdcmd[2];
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	62 #endif
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	63
149 ed9ca2a9705c Cleaned up the random code, use /dev/random by default, Matt Johnston <matt@ucc.asn.au> parents: 70 diff changeset	64 #ifdef DROPBEAR_RANDOM_DEV
446 2cd2edfa11ee Just use /dev/urandom since that's what everyone ends up using anyway. Matt Johnston <matt@ucc.asn.au> parents: 442 diff changeset	65 readfd = open(DROPBEAR_RANDOM_DEV, O_RDONLY);
70 b0316ce64e4b Merging in the changes from 0.41-0.43 main Dropbear tree Matt Johnston <matt@ucc.asn.au> parents: 4 diff changeset	66 if (readfd < 0) {
446 2cd2edfa11ee Just use /dev/urandom since that's what everyone ends up using anyway. Matt Johnston <matt@ucc.asn.au> parents: 442 diff changeset	67 dropbear_exit("couldn't open random device");
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	68 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	69 #endif
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	70
149 ed9ca2a9705c Cleaned up the random code, use /dev/random by default, Matt Johnston <matt@ucc.asn.au> parents: 70 diff changeset	71 #ifdef DROPBEAR_PRNGD_SOCKET
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	72 memset((void*)&egdsock, 0x0, sizeof(egdsock));
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	73 egdsock.sun_family = AF_UNIX;
159 4bd4fc8023bd random.c: fix missed instance of DROPBEAR_EGD_SOCKET Matt Johnston <matt@ucc.asn.au> parents: 149 diff changeset	74 strlcpy(egdsock.sun_path, DROPBEAR_PRNGD_SOCKET,
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	75 sizeof(egdsock.sun_path));
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	76
70 b0316ce64e4b Merging in the changes from 0.41-0.43 main Dropbear tree Matt Johnston <matt@ucc.asn.au> parents: 4 diff changeset	77 readfd = socket(PF_UNIX, SOCK_STREAM, 0);
b0316ce64e4b Merging in the changes from 0.41-0.43 main Dropbear tree Matt Johnston <matt@ucc.asn.au> parents: 4 diff changeset	78 if (readfd < 0) {
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	79 dropbear_exit("couldn't open random device");
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	80 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	81 /* todo - try various common locations */
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	82 if (connect(readfd, (struct sockaddr*)&egdsock,
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	83 sizeof(struct sockaddr_un)) < 0) {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	84 dropbear_exit("couldn't open random device");
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	85 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	86
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	87 if (buflen > 255)
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	88 dropbear_exit("can't request more than 255 bytes from egd");
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	89 egdcmd[0] = 0x02; /* blocking read */
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	90 egdcmd[1] = (unsigned char)buflen;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	91 if (write(readfd, egdcmd, 2) < 0)
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	92 dropbear_exit("can't send command to egd");
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	93 #endif
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	94
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	95 /* read the actual random data */
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	96 readpos = 0;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	97 do {
185 5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	98 if (!already_blocked)
5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	99 {
5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	100 int ret;
5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	101 struct timeval timeout;
5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	102 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	103
5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	104 timeout.tv_sec = 2; /* two seconds should be enough */
5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	105 timeout.tv_usec = 0;
5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	106
5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	107 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	108 FD_SET(readfd, &read_fds);
5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	109 ret = select(readfd + 1, &read_fds, NULL, NULL, &timeout);
5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	110 if (ret == 0)
5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	111 {
5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	112 dropbear_log(LOG_INFO, "Warning: Reading the random source seems to have blocked.\nIf you experience problems, you probably need to find a better entropy source.");
5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	113 already_blocked = 1;
5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	114 }
5ccad7634388 * warn if we seem to be blocking on /dev/random Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	115 }
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	116 readlen = read(readfd, &buf[readpos], buflen - readpos);
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	117 if (readlen <= 0) {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	118 if (readlen < 0 && errno == EINTR) {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	119 continue;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	120 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	121 dropbear_exit("error reading random source");
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	122 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	123 readpos += readlen;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	124 } while (readpos < buflen);
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	125
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	126 close (readfd);
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	127 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	128
149 ed9ca2a9705c Cleaned up the random code, use /dev/random by default, Matt Johnston <matt@ucc.asn.au> parents: 70 diff changeset	129 /* initialise the prng from /dev/(u)random or prngd */
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	130 void seedrandom() {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	131
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	132 unsigned char readbuf[INIT_SEED_SIZE];
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	133
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	134 hash_state hs;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	135
272 3be7ae2e8dfa Only read /dev/random once when the program starts Matt Johnston <matt@ucc.asn.au> parents: 198 diff changeset	136 /* initialise so that things won't warn about
311 36d21680a9d3 A few more fixups, make sure that variable declarations are the Matt Johnston <matt@ucc.asn.au> parents: 298 diff changeset	137 * hashing an undefined buffer */
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	138 if (!donerandinit) {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	139 m_burn(hashpool, sizeof(hashpool));
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	140 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	141
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	142 /* get the seed data */
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	143 readrand(readbuf, sizeof(readbuf));
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	144
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	145 /* hash in the new seed data */
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	146 sha1_init(&hs);
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	147 sha1_process(&hs, (void*)hashpool, sizeof(hashpool));
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	148 sha1_process(&hs, (void*)readbuf, sizeof(readbuf));
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	149 sha1_done(&hs, hashpool);
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	150
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	151 counter = 0;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	152 donerandinit = 1;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	153 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	154
272 3be7ae2e8dfa Only read /dev/random once when the program starts Matt Johnston <matt@ucc.asn.au> parents: 198 diff changeset	155 /* hash the current random pool with some unique identifiers
3be7ae2e8dfa Only read /dev/random once when the program starts Matt Johnston <matt@ucc.asn.au> parents: 198 diff changeset	156 * for this process and point-in-time. this is used to separate
3be7ae2e8dfa Only read /dev/random once when the program starts Matt Johnston <matt@ucc.asn.au> parents: 198 diff changeset	157 * the random pools for fork()ed processes. */
3be7ae2e8dfa Only read /dev/random once when the program starts Matt Johnston <matt@ucc.asn.au> parents: 198 diff changeset	158 void reseedrandom() {
3be7ae2e8dfa Only read /dev/random once when the program starts Matt Johnston <matt@ucc.asn.au> parents: 198 diff changeset	159
311 36d21680a9d3 A few more fixups, make sure that variable declarations are the Matt Johnston <matt@ucc.asn.au> parents: 298 diff changeset	160 pid_t pid;
36d21680a9d3 A few more fixups, make sure that variable declarations are the Matt Johnston <matt@ucc.asn.au> parents: 298 diff changeset	161 hash_state hs;
36d21680a9d3 A few more fixups, make sure that variable declarations are the Matt Johnston <matt@ucc.asn.au> parents: 298 diff changeset	162 struct timeval tv;
272 3be7ae2e8dfa Only read /dev/random once when the program starts Matt Johnston <matt@ucc.asn.au> parents: 198 diff changeset	163
3be7ae2e8dfa Only read /dev/random once when the program starts Matt Johnston <matt@ucc.asn.au> parents: 198 diff changeset	164 if (!donerandinit) {
3be7ae2e8dfa Only read /dev/random once when the program starts Matt Johnston <matt@ucc.asn.au> parents: 198 diff changeset	165 dropbear_exit("seedrandom not done");
3be7ae2e8dfa Only read /dev/random once when the program starts Matt Johnston <matt@ucc.asn.au> parents: 198 diff changeset	166 }
3be7ae2e8dfa Only read /dev/random once when the program starts Matt Johnston <matt@ucc.asn.au> parents: 198 diff changeset	167
311 36d21680a9d3 A few more fixups, make sure that variable declarations are the Matt Johnston <matt@ucc.asn.au> parents: 298 diff changeset	168 pid = getpid();
36d21680a9d3 A few more fixups, make sure that variable declarations are the Matt Johnston <matt@ucc.asn.au> parents: 298 diff changeset	169 gettimeofday(&tv, NULL);
272 3be7ae2e8dfa Only read /dev/random once when the program starts Matt Johnston <matt@ucc.asn.au> parents: 198 diff changeset	170
3be7ae2e8dfa Only read /dev/random once when the program starts Matt Johnston <matt@ucc.asn.au> parents: 198 diff changeset	171 sha1_init(&hs);
3be7ae2e8dfa Only read /dev/random once when the program starts Matt Johnston <matt@ucc.asn.au> parents: 198 diff changeset	172 sha1_process(&hs, (void*)hashpool, sizeof(hashpool));
3be7ae2e8dfa Only read /dev/random once when the program starts Matt Johnston <matt@ucc.asn.au> parents: 198 diff changeset	173 sha1_process(&hs, (void*)&pid, sizeof(pid));
3be7ae2e8dfa Only read /dev/random once when the program starts Matt Johnston <matt@ucc.asn.au> parents: 198 diff changeset	174 sha1_process(&hs, (void*)&tv, sizeof(tv));
3be7ae2e8dfa Only read /dev/random once when the program starts Matt Johnston <matt@ucc.asn.au> parents: 198 diff changeset	175 sha1_done(&hs, hashpool);
3be7ae2e8dfa Only read /dev/random once when the program starts Matt Johnston <matt@ucc.asn.au> parents: 198 diff changeset	176 }
3be7ae2e8dfa Only read /dev/random once when the program starts Matt Johnston <matt@ucc.asn.au> parents: 198 diff changeset	177
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	178 /* return len bytes of pseudo-random data */
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	179 void genrandom(unsigned char* buf, unsigned int len) {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	180
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	181 hash_state hs;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	182 unsigned char hash[SHA1_HASH_SIZE];
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	183 unsigned int copylen;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	184
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	185 if (!donerandinit) {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	186 dropbear_exit("seedrandom not done");
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	187 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	188
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	189 while (len > 0) {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	190 sha1_init(&hs);
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	191 sha1_process(&hs, (void*)hashpool, sizeof(hashpool));
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	192 sha1_process(&hs, (void*)&counter, sizeof(counter));
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	193 sha1_done(&hs, hash);
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	194
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	195 counter++;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	196 if (counter > MAX_COUNTER) {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	197 seedrandom();
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	198 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	199
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	200 copylen = MIN(len, SHA1_HASH_SIZE);
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	201 memcpy(buf, hash, copylen);
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	202 len -= copylen;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	203 buf += copylen;
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	204 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	205 m_burn(hash, sizeof(hash));
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	206 }
188 c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	207
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	208 /* 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	209 * 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	210 * 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	211 * 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	212 * */
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	213 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	214
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	215 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	216 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	217 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	218
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	219 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	220
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	221 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	222 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	223 len += 1;
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	224 }
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	225
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	226 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	227 do {
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	228 genrandom(randbuf, len);
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	229 /* 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	230 * MSB first.*/
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	231 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	232
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	233 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	234
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	235 /* 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	236 * 0 < rand < max */
405 00703f1df67a Remove extraneous tests in random mpint generation, Matt Johnston <matt@ucc.asn.au> parents: 311 diff changeset	237 } while (mp_cmp(rand, max) != MP_LT);
188 c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	238 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	239 m_free(randbuf);
c9483550701b - refactored random mp_int generation and byte->mp_int code Matt Johnston <matt@ucc.asn.au> parents: 159 diff changeset	240 }

Mercurial > dropbear

annotate random.c @ 447:278805938dcf