Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 1 | /* |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 2 | * Copyright (c) 2001-2002 Damien Miller. All rights reserved. |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 3 | * |
| 4 | * Redistribution and use in source and binary forms, with or without |
| 5 | * modification, are permitted provided that the following conditions |
| 6 | * are met: |
| 7 | * 1. Redistributions of source code must retain the above copyright |
| 8 | * notice, this list of conditions and the following disclaimer. |
| 9 | * 2. Redistributions in binary form must reproduce the above copyright |
| 10 | * notice, this list of conditions and the following disclaimer in the |
| 11 | * documentation and/or other materials provided with the distribution. |
| 12 | * |
| 13 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| 14 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| 15 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| 16 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 17 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| 18 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 19 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 20 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 21 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| 22 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 23 | */ |
| 24 | |
| 25 | #include "includes.h" |
| 26 | |
Damien Miller | 3717cda | 2006-03-15 14:02:36 +1100 | [diff] [blame] | 27 | #include <sys/types.h> |
| 28 | #include <sys/resource.h> |
| 29 | #include <sys/stat.h> |
| 30 | #include <sys/wait.h> |
Damien Miller | 8ec8c3e | 2006-07-10 20:35:38 +1000 | [diff] [blame] | 31 | #include <sys/socket.h> |
Darren Tucker | 4c65543 | 2006-08-05 15:57:40 +1000 | [diff] [blame] | 32 | |
| 33 | #include <stdarg.h> |
Damien Miller | 2d00e63 | 2006-07-24 13:53:19 +1000 | [diff] [blame] | 34 | #include <stddef.h> |
Darren Tucker | a8d51ee | 2007-03-13 07:35:38 +1100 | [diff] [blame] | 35 | #include <string.h> |
Damien Miller | 8ec8c3e | 2006-07-10 20:35:38 +1000 | [diff] [blame] | 36 | |
| 37 | #include <netinet/in.h> |
Darren Tucker | 46aa3e0 | 2006-09-02 15:32:40 +1000 | [diff] [blame] | 38 | #include <arpa/inet.h> |
Damien Miller | 3717cda | 2006-03-15 14:02:36 +1100 | [diff] [blame] | 39 | |
| 40 | #ifdef HAVE_SYS_UN_H |
| 41 | # include <sys/un.h> |
| 42 | #endif |
| 43 | |
Darren Tucker | deecec9 | 2006-07-12 22:44:34 +1000 | [diff] [blame] | 44 | #include <errno.h> |
Damien Miller | a1738e4 | 2006-07-10 21:33:04 +1000 | [diff] [blame] | 45 | #include <fcntl.h> |
Damien Miller | 9f2abc4 | 2006-07-10 20:53:08 +1000 | [diff] [blame] | 46 | #include <pwd.h> |
Damien Miller | 3717cda | 2006-03-15 14:02:36 +1100 | [diff] [blame] | 47 | #include <signal.h> |
Damien Miller | b8fe89c | 2006-07-24 14:51:00 +1000 | [diff] [blame] | 48 | #include <time.h> |
| 49 | #include <unistd.h> |
Damien Miller | 3717cda | 2006-03-15 14:02:36 +1100 | [diff] [blame] | 50 | |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 51 | #include <openssl/rand.h> |
| 52 | #include <openssl/sha.h> |
| 53 | #include <openssl/crypto.h> |
| 54 | |
| 55 | /* SunOS 4.4.4 needs this */ |
| 56 | #ifdef HAVE_FLOATINGPOINT_H |
| 57 | # include <floatingpoint.h> |
| 58 | #endif /* HAVE_FLOATINGPOINT_H */ |
| 59 | |
| 60 | #include "misc.h" |
| 61 | #include "xmalloc.h" |
| 62 | #include "atomicio.h" |
| 63 | #include "pathnames.h" |
| 64 | #include "log.h" |
| 65 | |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 66 | /* Number of bytes we write out */ |
| 67 | #define OUTPUT_SEED_SIZE 48 |
| 68 | |
| 69 | /* Length of on-disk seedfiles */ |
| 70 | #define SEED_FILE_SIZE 1024 |
| 71 | |
| 72 | /* Maximum number of command-line arguments to read from file */ |
| 73 | #define NUM_ARGS 10 |
| 74 | |
| 75 | /* Minimum number of usable commands to be considered sufficient */ |
| 76 | #define MIN_ENTROPY_SOURCES 16 |
| 77 | |
| 78 | /* Path to on-disk seed file (relative to user's home directory */ |
| 79 | #ifndef SSH_PRNG_SEED_FILE |
| 80 | # define SSH_PRNG_SEED_FILE _PATH_SSH_USER_DIR"/prng_seed" |
| 81 | #endif |
| 82 | |
| 83 | /* Path to PRNG commands list */ |
| 84 | #ifndef SSH_PRNG_COMMAND_FILE |
Damien Miller | 05eda43 | 2002-02-10 18:32:28 +1100 | [diff] [blame] | 85 | # define SSH_PRNG_COMMAND_FILE SSHDIR "/ssh_prng_cmds" |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 86 | #endif |
| 87 | |
Kevin Steves | 9443508 | 2001-12-25 04:32:58 +0000 | [diff] [blame] | 88 | extern char *__progname; |
Kevin Steves | 9443508 | 2001-12-25 04:32:58 +0000 | [diff] [blame] | 89 | |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 90 | #define WHITESPACE " \t\n" |
| 91 | |
| 92 | #ifndef RUSAGE_SELF |
| 93 | # define RUSAGE_SELF 0 |
| 94 | #endif |
| 95 | #ifndef RUSAGE_CHILDREN |
| 96 | # define RUSAGE_CHILDREN 0 |
| 97 | #endif |
| 98 | |
Damien Miller | c46cc54 | 2002-01-22 21:58:27 +1100 | [diff] [blame] | 99 | #if !defined(PRNGD_SOCKET) && !defined(PRNGD_PORT) |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 100 | # define USE_SEED_FILES |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 101 | #endif |
| 102 | |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 103 | typedef struct { |
| 104 | /* Proportion of data that is entropy */ |
| 105 | double rate; |
| 106 | /* Counter goes positive if this command times out */ |
| 107 | unsigned int badness; |
| 108 | /* Increases by factor of two each timeout */ |
| 109 | unsigned int sticky_badness; |
| 110 | /* Path to executable */ |
| 111 | char *path; |
| 112 | /* argv to pass to executable */ |
| 113 | char *args[NUM_ARGS]; /* XXX: arbitrary limit */ |
| 114 | /* full command string (debug) */ |
| 115 | char *cmdstring; |
| 116 | } entropy_cmd_t; |
| 117 | |
| 118 | /* slow command timeouts (all in milliseconds) */ |
| 119 | /* static int entropy_timeout_default = ENTROPY_TIMEOUT_MSEC; */ |
| 120 | static int entropy_timeout_current = ENTROPY_TIMEOUT_MSEC; |
| 121 | |
| 122 | /* this is initialised from a file, by prng_read_commands() */ |
| 123 | static entropy_cmd_t *entropy_cmds = NULL; |
| 124 | |
| 125 | /* Prototypes */ |
| 126 | double stir_from_system(void); |
| 127 | double stir_from_programs(void); |
| 128 | double stir_gettimeofday(double entropy_estimate); |
| 129 | double stir_clock(double entropy_estimate); |
| 130 | double stir_rusage(int who, double entropy_estimate); |
Kevin Steves | 4bdb547 | 2002-07-28 20:42:23 +0000 | [diff] [blame] | 131 | double hash_command_output(entropy_cmd_t *src, unsigned char *hash); |
Damien Miller | a8e06ce | 2003-11-21 23:48:55 +1100 | [diff] [blame] | 132 | int get_random_bytes_prngd(unsigned char *buf, int len, |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 133 | unsigned short tcp_port, char *socket_path); |
| 134 | |
| 135 | /* |
| 136 | * Collect 'len' bytes of entropy into 'buf' from PRNGD/EGD daemon |
| 137 | * listening either on 'tcp_port', or via Unix domain socket at * |
| 138 | * 'socket_path'. |
Damien Miller | a8e06ce | 2003-11-21 23:48:55 +1100 | [diff] [blame] | 139 | * Either a non-zero tcp_port or a non-null socket_path must be |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 140 | * supplied. |
| 141 | * Returns 0 on success, -1 on error |
| 142 | */ |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 143 | int |
Damien Miller | a8e06ce | 2003-11-21 23:48:55 +1100 | [diff] [blame] | 144 | get_random_bytes_prngd(unsigned char *buf, int len, |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 145 | unsigned short tcp_port, char *socket_path) |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 146 | { |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 147 | int fd, addr_len, rval, errors; |
Damien Miller | 52c8afe | 2005-06-19 10:19:43 +1000 | [diff] [blame] | 148 | u_char msg[2]; |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 149 | struct sockaddr_storage addr; |
| 150 | struct sockaddr_in *addr_in = (struct sockaddr_in *)&addr; |
| 151 | struct sockaddr_un *addr_un = (struct sockaddr_un *)&addr; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 152 | mysig_t old_sigpipe; |
| 153 | |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 154 | /* Sanity checks */ |
| 155 | if (socket_path == NULL && tcp_port == 0) |
| 156 | fatal("You must specify a port or a socket"); |
| 157 | if (socket_path != NULL && |
| 158 | strlen(socket_path) >= sizeof(addr_un->sun_path)) |
| 159 | fatal("Random pool path is too long"); |
Damien Miller | 52c8afe | 2005-06-19 10:19:43 +1000 | [diff] [blame] | 160 | if (len <= 0 || len > 255) |
| 161 | fatal("Too many bytes (%d) to read from PRNGD", len); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 162 | |
| 163 | memset(&addr, '\0', sizeof(addr)); |
| 164 | |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 165 | if (tcp_port != 0) { |
| 166 | addr_in->sin_family = AF_INET; |
| 167 | addr_in->sin_addr.s_addr = htonl(INADDR_LOOPBACK); |
| 168 | addr_in->sin_port = htons(tcp_port); |
| 169 | addr_len = sizeof(*addr_in); |
| 170 | } else { |
| 171 | addr_un->sun_family = AF_UNIX; |
| 172 | strlcpy(addr_un->sun_path, socket_path, |
| 173 | sizeof(addr_un->sun_path)); |
| 174 | addr_len = offsetof(struct sockaddr_un, sun_path) + |
| 175 | strlen(socket_path) + 1; |
| 176 | } |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 177 | |
| 178 | old_sigpipe = mysignal(SIGPIPE, SIG_IGN); |
| 179 | |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 180 | errors = 0; |
| 181 | rval = -1; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 182 | reopen: |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 183 | fd = socket(addr.ss_family, SOCK_STREAM, 0); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 184 | if (fd == -1) { |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 185 | error("Couldn't create socket: %s", strerror(errno)); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 186 | goto done; |
| 187 | } |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 188 | |
| 189 | if (connect(fd, (struct sockaddr*)&addr, addr_len) == -1) { |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 190 | if (tcp_port != 0) { |
| 191 | error("Couldn't connect to PRNGD port %d: %s", |
| 192 | tcp_port, strerror(errno)); |
| 193 | } else { |
| 194 | error("Couldn't connect to PRNGD socket \"%s\": %s", |
| 195 | addr_un->sun_path, strerror(errno)); |
| 196 | } |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 197 | goto done; |
| 198 | } |
| 199 | |
| 200 | /* Send blocking read request to PRNGD */ |
| 201 | msg[0] = 0x02; |
| 202 | msg[1] = len; |
| 203 | |
Darren Tucker | 8661b56 | 2003-07-06 15:20:46 +1000 | [diff] [blame] | 204 | if (atomicio(vwrite, fd, msg, sizeof(msg)) != sizeof(msg)) { |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 205 | if (errno == EPIPE && errors < 10) { |
| 206 | close(fd); |
| 207 | errors++; |
| 208 | goto reopen; |
| 209 | } |
| 210 | error("Couldn't write to PRNGD socket: %s", |
| 211 | strerror(errno)); |
| 212 | goto done; |
| 213 | } |
| 214 | |
Damien Miller | 52c8afe | 2005-06-19 10:19:43 +1000 | [diff] [blame] | 215 | if (atomicio(read, fd, buf, len) != (size_t)len) { |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 216 | if (errno == EPIPE && errors < 10) { |
| 217 | close(fd); |
| 218 | errors++; |
| 219 | goto reopen; |
| 220 | } |
| 221 | error("Couldn't read from PRNGD socket: %s", |
| 222 | strerror(errno)); |
| 223 | goto done; |
| 224 | } |
| 225 | |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 226 | rval = 0; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 227 | done: |
| 228 | mysignal(SIGPIPE, old_sigpipe); |
| 229 | if (fd != -1) |
| 230 | close(fd); |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 231 | return rval; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 232 | } |
| 233 | |
Darren Tucker | 8686ed7 | 2004-12-20 12:05:08 +1100 | [diff] [blame] | 234 | static int |
| 235 | seed_from_prngd(unsigned char *buf, size_t bytes) |
| 236 | { |
| 237 | #ifdef PRNGD_PORT |
| 238 | debug("trying egd/prngd port %d", PRNGD_PORT); |
| 239 | if (get_random_bytes_prngd(buf, bytes, PRNGD_PORT, NULL) == 0) |
| 240 | return 0; |
| 241 | #endif |
| 242 | #ifdef PRNGD_SOCKET |
| 243 | debug("trying egd/prngd socket %s", PRNGD_SOCKET); |
| 244 | if (get_random_bytes_prngd(buf, bytes, 0, PRNGD_SOCKET) == 0) |
| 245 | return 0; |
| 246 | #endif |
| 247 | return -1; |
| 248 | } |
| 249 | |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 250 | double |
| 251 | stir_gettimeofday(double entropy_estimate) |
| 252 | { |
| 253 | struct timeval tv; |
| 254 | |
| 255 | if (gettimeofday(&tv, NULL) == -1) |
| 256 | fatal("Couldn't gettimeofday: %s", strerror(errno)); |
| 257 | |
| 258 | RAND_add(&tv, sizeof(tv), entropy_estimate); |
| 259 | |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 260 | return entropy_estimate; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 261 | } |
| 262 | |
| 263 | double |
| 264 | stir_clock(double entropy_estimate) |
| 265 | { |
| 266 | #ifdef HAVE_CLOCK |
| 267 | clock_t c; |
| 268 | |
| 269 | c = clock(); |
| 270 | RAND_add(&c, sizeof(c), entropy_estimate); |
| 271 | |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 272 | return entropy_estimate; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 273 | #else /* _HAVE_CLOCK */ |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 274 | return 0; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 275 | #endif /* _HAVE_CLOCK */ |
| 276 | } |
| 277 | |
| 278 | double |
| 279 | stir_rusage(int who, double entropy_estimate) |
| 280 | { |
| 281 | #ifdef HAVE_GETRUSAGE |
| 282 | struct rusage ru; |
| 283 | |
| 284 | if (getrusage(who, &ru) == -1) |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 285 | return 0; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 286 | |
| 287 | RAND_add(&ru, sizeof(ru), entropy_estimate); |
| 288 | |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 289 | return entropy_estimate; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 290 | #else /* _HAVE_GETRUSAGE */ |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 291 | return 0; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 292 | #endif /* _HAVE_GETRUSAGE */ |
| 293 | } |
| 294 | |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 295 | static int |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 296 | timeval_diff(struct timeval *t1, struct timeval *t2) |
| 297 | { |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 298 | int secdiff, usecdiff; |
| 299 | |
| 300 | secdiff = t2->tv_sec - t1->tv_sec; |
| 301 | usecdiff = (secdiff*1000000) + (t2->tv_usec - t1->tv_usec); |
| 302 | return (int)(usecdiff / 1000); |
| 303 | } |
| 304 | |
| 305 | double |
Kevin Steves | 4bdb547 | 2002-07-28 20:42:23 +0000 | [diff] [blame] | 306 | hash_command_output(entropy_cmd_t *src, unsigned char *hash) |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 307 | { |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 308 | char buf[8192]; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 309 | fd_set rdset; |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 310 | int bytes_read, cmd_eof, error_abort, msec_elapsed, p[2]; |
| 311 | int status, total_bytes_read; |
| 312 | static int devnull = -1; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 313 | pid_t pid; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 314 | SHA_CTX sha; |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 315 | struct timeval tv_start, tv_current; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 316 | |
| 317 | debug3("Reading output from \'%s\'", src->cmdstring); |
| 318 | |
| 319 | if (devnull == -1) { |
| 320 | devnull = open("/dev/null", O_RDWR); |
| 321 | if (devnull == -1) |
Damien Miller | a8e06ce | 2003-11-21 23:48:55 +1100 | [diff] [blame] | 322 | fatal("Couldn't open /dev/null: %s", |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 323 | strerror(errno)); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 324 | } |
| 325 | |
| 326 | if (pipe(p) == -1) |
| 327 | fatal("Couldn't open pipe: %s", strerror(errno)); |
| 328 | |
| 329 | (void)gettimeofday(&tv_start, NULL); /* record start time */ |
| 330 | |
| 331 | switch (pid = fork()) { |
| 332 | case -1: /* Error */ |
| 333 | close(p[0]); |
| 334 | close(p[1]); |
| 335 | fatal("Couldn't fork: %s", strerror(errno)); |
| 336 | /* NOTREACHED */ |
| 337 | case 0: /* Child */ |
| 338 | dup2(devnull, STDIN_FILENO); |
| 339 | dup2(p[1], STDOUT_FILENO); |
| 340 | dup2(p[1], STDERR_FILENO); |
| 341 | close(p[0]); |
| 342 | close(p[1]); |
| 343 | close(devnull); |
| 344 | |
| 345 | execv(src->path, (char**)(src->args)); |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 346 | |
Damien Miller | a8e06ce | 2003-11-21 23:48:55 +1100 | [diff] [blame] | 347 | debug("(child) Couldn't exec '%s': %s", |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 348 | src->cmdstring, strerror(errno)); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 349 | _exit(-1); |
| 350 | default: /* Parent */ |
| 351 | break; |
| 352 | } |
| 353 | |
| 354 | RAND_add(&pid, sizeof(&pid), 0.0); |
| 355 | |
| 356 | close(p[1]); |
| 357 | |
| 358 | /* Hash output from child */ |
| 359 | SHA1_Init(&sha); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 360 | |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 361 | cmd_eof = error_abort = msec_elapsed = total_bytes_read = 0; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 362 | while (!error_abort && !cmd_eof) { |
| 363 | int ret; |
| 364 | struct timeval tv; |
| 365 | int msec_remaining; |
| 366 | |
| 367 | (void) gettimeofday(&tv_current, 0); |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 368 | msec_elapsed = timeval_diff(&tv_start, &tv_current); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 369 | if (msec_elapsed >= entropy_timeout_current) { |
| 370 | error_abort=1; |
| 371 | continue; |
| 372 | } |
| 373 | msec_remaining = entropy_timeout_current - msec_elapsed; |
| 374 | |
| 375 | FD_ZERO(&rdset); |
| 376 | FD_SET(p[0], &rdset); |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 377 | tv.tv_sec = msec_remaining / 1000; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 378 | tv.tv_usec = (msec_remaining % 1000) * 1000; |
| 379 | |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 380 | ret = select(p[0] + 1, &rdset, NULL, NULL, &tv); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 381 | |
| 382 | RAND_add(&tv, sizeof(tv), 0.0); |
| 383 | |
| 384 | switch (ret) { |
| 385 | case 0: |
| 386 | /* timer expired */ |
| 387 | error_abort = 1; |
Damien Miller | 5a5da88 | 2002-10-21 10:13:35 +1000 | [diff] [blame] | 388 | kill(pid, SIGINT); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 389 | break; |
| 390 | case 1: |
| 391 | /* command input */ |
| 392 | do { |
| 393 | bytes_read = read(p[0], buf, sizeof(buf)); |
| 394 | } while (bytes_read == -1 && errno == EINTR); |
| 395 | RAND_add(&bytes_read, sizeof(&bytes_read), 0.0); |
| 396 | if (bytes_read == -1) { |
| 397 | error_abort = 1; |
| 398 | break; |
| 399 | } else if (bytes_read) { |
| 400 | SHA1_Update(&sha, buf, bytes_read); |
| 401 | total_bytes_read += bytes_read; |
| 402 | } else { |
| 403 | cmd_eof = 1; |
| 404 | } |
| 405 | break; |
| 406 | case -1: |
| 407 | default: |
| 408 | /* error */ |
Damien Miller | a8e06ce | 2003-11-21 23:48:55 +1100 | [diff] [blame] | 409 | debug("Command '%s': select() failed: %s", |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 410 | src->cmdstring, strerror(errno)); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 411 | error_abort = 1; |
| 412 | break; |
| 413 | } |
| 414 | } |
| 415 | |
| 416 | SHA1_Final(hash, &sha); |
| 417 | |
| 418 | close(p[0]); |
| 419 | |
| 420 | debug3("Time elapsed: %d msec", msec_elapsed); |
| 421 | |
| 422 | if (waitpid(pid, &status, 0) == -1) { |
Damien Miller | b6f72f5 | 2005-07-17 17:26:43 +1000 | [diff] [blame] | 423 | error("Couldn't wait for child '%s' completion: %s", |
| 424 | src->cmdstring, strerror(errno)); |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 425 | return 0.0; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 426 | } |
| 427 | |
| 428 | RAND_add(&status, sizeof(&status), 0.0); |
| 429 | |
| 430 | if (error_abort) { |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 431 | /* |
| 432 | * Closing p[0] on timeout causes the entropy command to |
Damien Miller | a8e06ce | 2003-11-21 23:48:55 +1100 | [diff] [blame] | 433 | * SIGPIPE. Take whatever output we got, and mark this |
| 434 | * command as slow |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 435 | */ |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 436 | debug2("Command '%s' timed out", src->cmdstring); |
| 437 | src->sticky_badness *= 2; |
| 438 | src->badness = src->sticky_badness; |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 439 | return total_bytes_read; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 440 | } |
| 441 | |
| 442 | if (WIFEXITED(status)) { |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 443 | if (WEXITSTATUS(status) == 0) { |
| 444 | return total_bytes_read; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 445 | } else { |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 446 | debug2("Command '%s' exit status was %d", |
| 447 | src->cmdstring, WEXITSTATUS(status)); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 448 | src->badness = src->sticky_badness = 128; |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 449 | return 0.0; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 450 | } |
| 451 | } else if (WIFSIGNALED(status)) { |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 452 | debug2("Command '%s' returned on uncaught signal %d !", |
| 453 | src->cmdstring, status); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 454 | src->badness = src->sticky_badness = 128; |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 455 | return 0.0; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 456 | } else |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 457 | return 0.0; |
| 458 | } |
| 459 | |
| 460 | double |
| 461 | stir_from_system(void) |
| 462 | { |
| 463 | double total_entropy_estimate; |
| 464 | long int i; |
| 465 | |
| 466 | total_entropy_estimate = 0; |
| 467 | |
| 468 | i = getpid(); |
| 469 | RAND_add(&i, sizeof(i), 0.5); |
| 470 | total_entropy_estimate += 0.1; |
| 471 | |
| 472 | i = getppid(); |
| 473 | RAND_add(&i, sizeof(i), 0.5); |
| 474 | total_entropy_estimate += 0.1; |
| 475 | |
| 476 | i = getuid(); |
| 477 | RAND_add(&i, sizeof(i), 0.0); |
| 478 | i = getgid(); |
| 479 | RAND_add(&i, sizeof(i), 0.0); |
| 480 | |
| 481 | total_entropy_estimate += stir_gettimeofday(1.0); |
| 482 | total_entropy_estimate += stir_clock(0.5); |
| 483 | total_entropy_estimate += stir_rusage(RUSAGE_SELF, 2.0); |
| 484 | |
| 485 | return total_entropy_estimate; |
| 486 | } |
| 487 | |
| 488 | double |
| 489 | stir_from_programs(void) |
| 490 | { |
| 491 | int c; |
| 492 | double entropy, total_entropy; |
Kevin Steves | 4bdb547 | 2002-07-28 20:42:23 +0000 | [diff] [blame] | 493 | unsigned char hash[SHA_DIGEST_LENGTH]; |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 494 | |
| 495 | total_entropy = 0; |
| 496 | for(c = 0; entropy_cmds[c].path != NULL; c++) { |
| 497 | if (!entropy_cmds[c].badness) { |
| 498 | /* Hash output from command */ |
| 499 | entropy = hash_command_output(&entropy_cmds[c], |
| 500 | hash); |
| 501 | |
| 502 | /* Scale back estimate by command's rate */ |
| 503 | entropy *= entropy_cmds[c].rate; |
| 504 | |
| 505 | /* Upper bound of entropy is SHA_DIGEST_LENGTH */ |
| 506 | if (entropy > SHA_DIGEST_LENGTH) |
| 507 | entropy = SHA_DIGEST_LENGTH; |
| 508 | |
| 509 | /* Stir it in */ |
| 510 | RAND_add(hash, sizeof(hash), entropy); |
| 511 | |
Damien Miller | a8e06ce | 2003-11-21 23:48:55 +1100 | [diff] [blame] | 512 | debug3("Got %0.2f bytes of entropy from '%s'", |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 513 | entropy, entropy_cmds[c].cmdstring); |
| 514 | |
| 515 | total_entropy += entropy; |
| 516 | |
| 517 | /* Execution time should be a bit unpredictable */ |
| 518 | total_entropy += stir_gettimeofday(0.05); |
| 519 | total_entropy += stir_clock(0.05); |
| 520 | total_entropy += stir_rusage(RUSAGE_SELF, 0.1); |
| 521 | total_entropy += stir_rusage(RUSAGE_CHILDREN, 0.1); |
| 522 | } else { |
| 523 | debug2("Command '%s' disabled (badness %d)", |
Damien Miller | a8e06ce | 2003-11-21 23:48:55 +1100 | [diff] [blame] | 524 | entropy_cmds[c].cmdstring, |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 525 | entropy_cmds[c].badness); |
| 526 | |
| 527 | if (entropy_cmds[c].badness > 0) |
| 528 | entropy_cmds[c].badness--; |
| 529 | } |
| 530 | } |
| 531 | |
| 532 | return total_entropy; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 533 | } |
| 534 | |
| 535 | /* |
| 536 | * prng seedfile functions |
| 537 | */ |
| 538 | int |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 539 | prng_check_seedfile(char *filename) |
| 540 | { |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 541 | struct stat st; |
| 542 | |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 543 | /* |
Damien Miller | a8e06ce | 2003-11-21 23:48:55 +1100 | [diff] [blame] | 544 | * XXX raceable: eg replace seed between this stat and subsequent |
| 545 | * open. Not such a problem because we don't really trust the |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 546 | * seed file anyway. |
| 547 | * XXX: use secure path checking as elsewhere in OpenSSH |
| 548 | */ |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 549 | if (lstat(filename, &st) == -1) { |
| 550 | /* Give up on hard errors */ |
| 551 | if (errno != ENOENT) |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 552 | debug("WARNING: Couldn't stat random seed file " |
| 553 | "\"%.100s\": %s", filename, strerror(errno)); |
| 554 | return 0; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 555 | } |
| 556 | |
| 557 | /* regular file? */ |
| 558 | if (!S_ISREG(st.st_mode)) |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 559 | fatal("PRNG seedfile %.100s is not a regular file", |
| 560 | filename); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 561 | |
| 562 | /* mode 0600, owned by root or the current user? */ |
| 563 | if (((st.st_mode & 0177) != 0) || !(st.st_uid == getuid())) { |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 564 | debug("WARNING: PRNG seedfile %.100s must be mode 0600, " |
Damien Miller | c46b6bc | 2003-05-16 15:51:44 +1000 | [diff] [blame] | 565 | "owned by uid %li", filename, (long int)getuid()); |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 566 | return 0; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 567 | } |
| 568 | |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 569 | return 1; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 570 | } |
| 571 | |
| 572 | void |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 573 | prng_write_seedfile(void) |
| 574 | { |
Damien Miller | ed462d9 | 2005-02-16 13:02:45 +1100 | [diff] [blame] | 575 | int fd, save_errno; |
Kevin Steves | 4bdb547 | 2002-07-28 20:42:23 +0000 | [diff] [blame] | 576 | unsigned char seed[SEED_FILE_SIZE]; |
Damien Miller | ed462d9 | 2005-02-16 13:02:45 +1100 | [diff] [blame] | 577 | char filename[MAXPATHLEN], tmpseed[MAXPATHLEN]; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 578 | struct passwd *pw; |
Damien Miller | ed462d9 | 2005-02-16 13:02:45 +1100 | [diff] [blame] | 579 | mode_t old_umask; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 580 | |
| 581 | pw = getpwuid(getuid()); |
| 582 | if (pw == NULL) |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 583 | fatal("Couldn't get password entry for current user " |
Damien Miller | c46b6bc | 2003-05-16 15:51:44 +1000 | [diff] [blame] | 584 | "(%li): %s", (long int)getuid(), strerror(errno)); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 585 | |
| 586 | /* Try to ensure that the parent directory is there */ |
| 587 | snprintf(filename, sizeof(filename), "%.512s/%s", pw->pw_dir, |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 588 | _PATH_SSH_USER_DIR); |
Darren Tucker | daf6ff4 | 2006-07-05 21:35:48 +1000 | [diff] [blame] | 589 | if (mkdir(filename, 0700) < 0 && errno != EEXIST) |
| 590 | fatal("mkdir %.200s: %s", filename, strerror(errno)); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 591 | |
| 592 | snprintf(filename, sizeof(filename), "%.512s/%s", pw->pw_dir, |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 593 | SSH_PRNG_SEED_FILE); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 594 | |
Damien Miller | ed462d9 | 2005-02-16 13:02:45 +1100 | [diff] [blame] | 595 | strlcpy(tmpseed, filename, sizeof(tmpseed)); |
| 596 | if (strlcat(tmpseed, ".XXXXXXXXXX", sizeof(tmpseed)) >= |
| 597 | sizeof(tmpseed)) |
| 598 | fatal("PRNG seed filename too long"); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 599 | |
Damien Miller | cafbcc7 | 2003-03-17 16:13:53 +1100 | [diff] [blame] | 600 | if (RAND_bytes(seed, sizeof(seed)) <= 0) |
Ben Lindstrom | da4d9cf | 2003-09-22 15:36:15 +0000 | [diff] [blame] | 601 | fatal("PRNG seed extraction failed"); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 602 | |
| 603 | /* Don't care if the seed doesn't exist */ |
| 604 | prng_check_seedfile(filename); |
| 605 | |
Damien Miller | ed462d9 | 2005-02-16 13:02:45 +1100 | [diff] [blame] | 606 | old_umask = umask(0177); |
| 607 | |
| 608 | if ((fd = mkstemp(tmpseed)) == -1) { |
| 609 | debug("WARNING: couldn't make temporary PRNG seedfile %.100s " |
| 610 | "(%.100s)", tmpseed, strerror(errno)); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 611 | } else { |
Damien Miller | ed462d9 | 2005-02-16 13:02:45 +1100 | [diff] [blame] | 612 | debug("writing PRNG seed to file %.100s", tmpseed); |
| 613 | if (atomicio(vwrite, fd, &seed, sizeof(seed)) < sizeof(seed)) { |
| 614 | save_errno = errno; |
| 615 | close(fd); |
| 616 | unlink(tmpseed); |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 617 | fatal("problem writing PRNG seedfile %.100s " |
Damien Miller | ed462d9 | 2005-02-16 13:02:45 +1100 | [diff] [blame] | 618 | "(%.100s)", filename, strerror(save_errno)); |
| 619 | } |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 620 | close(fd); |
Damien Miller | ed462d9 | 2005-02-16 13:02:45 +1100 | [diff] [blame] | 621 | debug("moving temporary PRNG seed to file %.100s", filename); |
| 622 | if (rename(tmpseed, filename) == -1) { |
| 623 | save_errno = errno; |
| 624 | unlink(tmpseed); |
| 625 | fatal("problem renaming PRNG seedfile from %.100s " |
Damien Miller | 94cf4c8 | 2005-07-17 17:04:47 +1000 | [diff] [blame] | 626 | "to %.100s (%.100s)", tmpseed, filename, |
Damien Miller | ed462d9 | 2005-02-16 13:02:45 +1100 | [diff] [blame] | 627 | strerror(save_errno)); |
| 628 | } |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 629 | } |
Damien Miller | ed462d9 | 2005-02-16 13:02:45 +1100 | [diff] [blame] | 630 | umask(old_umask); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 631 | } |
| 632 | |
| 633 | void |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 634 | prng_read_seedfile(void) |
| 635 | { |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 636 | int fd; |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 637 | char seed[SEED_FILE_SIZE], filename[MAXPATHLEN]; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 638 | struct passwd *pw; |
| 639 | |
| 640 | pw = getpwuid(getuid()); |
| 641 | if (pw == NULL) |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 642 | fatal("Couldn't get password entry for current user " |
Damien Miller | c46b6bc | 2003-05-16 15:51:44 +1000 | [diff] [blame] | 643 | "(%li): %s", (long int)getuid(), strerror(errno)); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 644 | |
| 645 | snprintf(filename, sizeof(filename), "%.512s/%s", pw->pw_dir, |
| 646 | SSH_PRNG_SEED_FILE); |
| 647 | |
| 648 | debug("loading PRNG seed from file %.100s", filename); |
| 649 | |
| 650 | if (!prng_check_seedfile(filename)) { |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 651 | verbose("Random seed file not found or invalid, ignoring."); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 652 | return; |
| 653 | } |
| 654 | |
| 655 | /* open the file and read in the seed */ |
| 656 | fd = open(filename, O_RDONLY); |
| 657 | if (fd == -1) |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 658 | fatal("could not open PRNG seedfile %.100s (%.100s)", |
| 659 | filename, strerror(errno)); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 660 | |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 661 | if (atomicio(read, fd, &seed, sizeof(seed)) < sizeof(seed)) { |
| 662 | verbose("invalid or short read from PRNG seedfile " |
| 663 | "%.100s - ignoring", filename); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 664 | memset(seed, '\0', sizeof(seed)); |
| 665 | } |
| 666 | close(fd); |
| 667 | |
| 668 | /* stir in the seed, with estimated entropy zero */ |
| 669 | RAND_add(&seed, sizeof(seed), 0.0); |
| 670 | } |
| 671 | |
| 672 | |
| 673 | /* |
| 674 | * entropy command initialisation functions |
| 675 | */ |
| 676 | int |
| 677 | prng_read_commands(char *cmdfilename) |
| 678 | { |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 679 | char cmd[SEED_FILE_SIZE], *cp, line[1024], path[SEED_FILE_SIZE]; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 680 | double est; |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 681 | entropy_cmd_t *entcmd; |
| 682 | FILE *f; |
| 683 | int cur_cmd, linenum, num_cmds, arg; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 684 | |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 685 | if ((f = fopen(cmdfilename, "r")) == NULL) { |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 686 | fatal("couldn't read entropy commands file %.100s: %.100s", |
| 687 | cmdfilename, strerror(errno)); |
| 688 | } |
| 689 | |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 690 | num_cmds = 64; |
Darren Tucker | d8093e4 | 2006-05-04 16:24:34 +1000 | [diff] [blame] | 691 | entcmd = xcalloc(num_cmds, sizeof(entropy_cmd_t)); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 692 | |
| 693 | /* Read in file */ |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 694 | cur_cmd = linenum = 0; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 695 | while (fgets(line, sizeof(line), f)) { |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 696 | linenum++; |
| 697 | |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 698 | /* Skip leading whitespace, blank lines and comments */ |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 699 | cp = line + strspn(line, WHITESPACE); |
| 700 | if ((*cp == 0) || (*cp == '#')) |
| 701 | continue; /* done with this line */ |
| 702 | |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 703 | /* |
Damien Miller | a8e06ce | 2003-11-21 23:48:55 +1100 | [diff] [blame] | 704 | * The first non-whitespace char should be a double quote |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 705 | * delimiting the commandline |
| 706 | */ |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 707 | if (*cp != '"') { |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 708 | error("bad entropy command, %.100s line %d", |
| 709 | cmdfilename, linenum); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 710 | continue; |
| 711 | } |
| 712 | |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 713 | /* |
| 714 | * First token, command args (incl. argv[0]) in double |
| 715 | * quotes |
| 716 | */ |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 717 | cp = strtok(cp, "\""); |
| 718 | if (cp == NULL) { |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 719 | error("missing or bad command string, %.100s " |
| 720 | "line %d -- ignored", cmdfilename, linenum); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 721 | continue; |
| 722 | } |
| 723 | strlcpy(cmd, cp, sizeof(cmd)); |
| 724 | |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 725 | /* Second token, full command path */ |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 726 | if ((cp = strtok(NULL, WHITESPACE)) == NULL) { |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 727 | error("missing command path, %.100s " |
| 728 | "line %d -- ignored", cmdfilename, linenum); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 729 | continue; |
| 730 | } |
| 731 | |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 732 | /* Did configure mark this as dead? */ |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 733 | if (strncmp("undef", cp, 5) == 0) |
| 734 | continue; |
| 735 | |
| 736 | strlcpy(path, cp, sizeof(path)); |
| 737 | |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 738 | /* Third token, entropy rate estimate for this command */ |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 739 | if ((cp = strtok(NULL, WHITESPACE)) == NULL) { |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 740 | error("missing entropy estimate, %.100s " |
| 741 | "line %d -- ignored", cmdfilename, linenum); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 742 | continue; |
| 743 | } |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 744 | est = strtod(cp, NULL); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 745 | |
| 746 | /* end of line */ |
| 747 | if ((cp = strtok(NULL, WHITESPACE)) != NULL) { |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 748 | error("garbage at end of line %d in %.100s " |
| 749 | "-- ignored", linenum, cmdfilename); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 750 | continue; |
| 751 | } |
| 752 | |
| 753 | /* save the command for debug messages */ |
| 754 | entcmd[cur_cmd].cmdstring = xstrdup(cmd); |
| 755 | |
| 756 | /* split the command args */ |
| 757 | cp = strtok(cmd, WHITESPACE); |
| 758 | arg = 0; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 759 | do { |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 760 | entcmd[cur_cmd].args[arg] = xstrdup(cp); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 761 | arg++; |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 762 | } while(arg < NUM_ARGS && (cp = strtok(NULL, WHITESPACE))); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 763 | |
| 764 | if (strtok(NULL, WHITESPACE)) |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 765 | error("ignored extra commands (max %d), %.100s " |
| 766 | "line %d", NUM_ARGS, cmdfilename, linenum); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 767 | |
| 768 | /* Copy the command path and rate estimate */ |
| 769 | entcmd[cur_cmd].path = xstrdup(path); |
| 770 | entcmd[cur_cmd].rate = est; |
| 771 | |
| 772 | /* Initialise other values */ |
| 773 | entcmd[cur_cmd].sticky_badness = 1; |
| 774 | |
| 775 | cur_cmd++; |
| 776 | |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 777 | /* |
| 778 | * If we've filled the array, reallocate it twice the size |
Damien Miller | a8e06ce | 2003-11-21 23:48:55 +1100 | [diff] [blame] | 779 | * Do this now because even if this we're on the last |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 780 | * command we need another slot to mark the last entry |
| 781 | */ |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 782 | if (cur_cmd == num_cmds) { |
| 783 | num_cmds *= 2; |
Damien Miller | 3681209 | 2006-03-26 14:22:47 +1100 | [diff] [blame] | 784 | entcmd = xrealloc(entcmd, num_cmds, |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 785 | sizeof(entropy_cmd_t)); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 786 | } |
| 787 | } |
| 788 | |
| 789 | /* zero the last entry */ |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 790 | memset(&entcmd[cur_cmd], '\0', sizeof(entropy_cmd_t)); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 791 | |
| 792 | /* trim to size */ |
Damien Miller | 3681209 | 2006-03-26 14:22:47 +1100 | [diff] [blame] | 793 | entropy_cmds = xrealloc(entcmd, (cur_cmd + 1), |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 794 | sizeof(entropy_cmd_t)); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 795 | |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 796 | debug("Loaded %d entropy commands from %.100s", cur_cmd, |
| 797 | cmdfilename); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 798 | |
Darren Tucker | f58b29d | 2006-05-17 22:24:56 +1000 | [diff] [blame] | 799 | fclose(f); |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 800 | return cur_cmd < MIN_ENTROPY_SOURCES ? -1 : 0; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 801 | } |
| 802 | |
Damien Miller | 32e4818 | 2002-04-14 19:27:12 +1000 | [diff] [blame] | 803 | void |
| 804 | usage(void) |
| 805 | { |
| 806 | fprintf(stderr, "Usage: %s [options]\n", __progname); |
| 807 | fprintf(stderr, " -v Verbose; display verbose debugging messages.\n"); |
| 808 | fprintf(stderr, " Multiple -v increases verbosity.\n"); |
Damien Miller | 7daf044 | 2004-08-23 21:52:08 +1000 | [diff] [blame] | 809 | fprintf(stderr, " -x Force output in hexadecimal (for debugging)\n"); |
Damien Miller | 32e4818 | 2002-04-14 19:27:12 +1000 | [diff] [blame] | 810 | fprintf(stderr, " -X Force output in binary\n"); |
| 811 | fprintf(stderr, " -b bytes Number of bytes to output (default %d)\n", |
| 812 | OUTPUT_SEED_SIZE); |
| 813 | } |
| 814 | |
Damien Miller | a8e06ce | 2003-11-21 23:48:55 +1100 | [diff] [blame] | 815 | int |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 816 | main(int argc, char **argv) |
| 817 | { |
Damien Miller | 32e4818 | 2002-04-14 19:27:12 +1000 | [diff] [blame] | 818 | unsigned char *buf; |
| 819 | int ret, ch, debug_level, output_hex, bytes; |
| 820 | extern char *optarg; |
| 821 | LogLevel ll; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 822 | |
Damien Miller | 59d3d5b | 2003-08-22 09:34:41 +1000 | [diff] [blame] | 823 | __progname = ssh_get_progname(argv[0]); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 824 | log_init(argv[0], SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_USER, 1); |
| 825 | |
Damien Miller | 32e4818 | 2002-04-14 19:27:12 +1000 | [diff] [blame] | 826 | ll = SYSLOG_LEVEL_INFO; |
| 827 | debug_level = output_hex = 0; |
| 828 | bytes = OUTPUT_SEED_SIZE; |
| 829 | |
| 830 | /* Don't write binary data to a tty, unless we are forced to */ |
| 831 | if (isatty(STDOUT_FILENO)) |
| 832 | output_hex = 1; |
Damien Miller | 787b2ec | 2003-11-21 23:56:47 +1100 | [diff] [blame] | 833 | |
Damien Miller | 32e4818 | 2002-04-14 19:27:12 +1000 | [diff] [blame] | 834 | while ((ch = getopt(argc, argv, "vxXhb:")) != -1) { |
| 835 | switch (ch) { |
| 836 | case 'v': |
| 837 | if (debug_level < 3) |
| 838 | ll = SYSLOG_LEVEL_DEBUG1 + debug_level++; |
| 839 | break; |
| 840 | case 'x': |
| 841 | output_hex = 1; |
| 842 | break; |
| 843 | case 'X': |
| 844 | output_hex = 0; |
| 845 | break; |
| 846 | case 'b': |
| 847 | if ((bytes = atoi(optarg)) <= 0) |
| 848 | fatal("Invalid number of output bytes"); |
| 849 | break; |
| 850 | case 'h': |
| 851 | usage(); |
| 852 | exit(0); |
| 853 | default: |
| 854 | error("Invalid commandline option"); |
| 855 | usage(); |
Damien Miller | 409661f | 2009-11-20 15:16:35 +1100 | [diff] [blame] | 856 | exit(1); |
Damien Miller | 32e4818 | 2002-04-14 19:27:12 +1000 | [diff] [blame] | 857 | } |
| 858 | } |
Damien Miller | 32e4818 | 2002-04-14 19:27:12 +1000 | [diff] [blame] | 859 | log_init(argv[0], ll, SYSLOG_FACILITY_USER, 1); |
Damien Miller | 787b2ec | 2003-11-21 23:56:47 +1100 | [diff] [blame] | 860 | |
Damien Miller | 409661f | 2009-11-20 15:16:35 +1100 | [diff] [blame] | 861 | if (argc != optind) { |
| 862 | error("Unexpected commandline arguments."); |
| 863 | usage(); |
| 864 | exit(1); |
| 865 | } |
| 866 | |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 867 | #ifdef USE_SEED_FILES |
| 868 | prng_read_seedfile(); |
| 869 | #endif |
| 870 | |
Damien Miller | 32e4818 | 2002-04-14 19:27:12 +1000 | [diff] [blame] | 871 | buf = xmalloc(bytes); |
| 872 | |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 873 | /* |
| 874 | * Seed the RNG from wherever we can |
| 875 | */ |
Damien Miller | 787b2ec | 2003-11-21 23:56:47 +1100 | [diff] [blame] | 876 | |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 877 | /* Take whatever is on the stack, but don't credit it */ |
Damien Miller | 32e4818 | 2002-04-14 19:27:12 +1000 | [diff] [blame] | 878 | RAND_add(buf, bytes, 0); |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 879 | |
Damien Miller | a8e06ce | 2003-11-21 23:48:55 +1100 | [diff] [blame] | 880 | debug("Seeded RNG with %i bytes from system calls", |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 881 | (int)stir_from_system()); |
| 882 | |
Darren Tucker | 8686ed7 | 2004-12-20 12:05:08 +1100 | [diff] [blame] | 883 | /* try prngd, fall back to commands if prngd fails or not configured */ |
| 884 | if (seed_from_prngd(buf, bytes) == 0) { |
| 885 | RAND_add(buf, bytes, bytes); |
| 886 | } else { |
| 887 | /* Read in collection commands */ |
| 888 | if (prng_read_commands(SSH_PRNG_COMMAND_FILE) == -1) |
| 889 | fatal("PRNG initialisation failed -- exiting."); |
| 890 | debug("Seeded RNG with %i bytes from programs", |
| 891 | (int)stir_from_programs()); |
| 892 | } |
Damien Miller | 7b10ef4 | 2002-01-21 23:44:12 +1100 | [diff] [blame] | 893 | |
| 894 | #ifdef USE_SEED_FILES |
| 895 | prng_write_seedfile(); |
| 896 | #endif |
| 897 | |
| 898 | /* |
| 899 | * Write the seed to stdout |
| 900 | */ |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 901 | |
| 902 | if (!RAND_status()) |
| 903 | fatal("Not enough entropy in RNG"); |
| 904 | |
Damien Miller | cafbcc7 | 2003-03-17 16:13:53 +1100 | [diff] [blame] | 905 | if (RAND_bytes(buf, bytes) <= 0) |
| 906 | fatal("Couldn't extract entropy from PRNG"); |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 907 | |
Damien Miller | 32e4818 | 2002-04-14 19:27:12 +1000 | [diff] [blame] | 908 | if (output_hex) { |
| 909 | for(ret = 0; ret < bytes; ret++) |
| 910 | printf("%02x", (unsigned char)(buf[ret])); |
| 911 | printf("\n"); |
| 912 | } else |
Darren Tucker | 8661b56 | 2003-07-06 15:20:46 +1000 | [diff] [blame] | 913 | ret = atomicio(vwrite, STDOUT_FILENO, buf, bytes); |
Damien Miller | 787b2ec | 2003-11-21 23:56:47 +1100 | [diff] [blame] | 914 | |
Damien Miller | 32e4818 | 2002-04-14 19:27:12 +1000 | [diff] [blame] | 915 | memset(buf, '\0', bytes); |
| 916 | xfree(buf); |
Damien Miller | 787b2ec | 2003-11-21 23:56:47 +1100 | [diff] [blame] | 917 | |
Damien Miller | 32e4818 | 2002-04-14 19:27:12 +1000 | [diff] [blame] | 918 | return ret == bytes ? 0 : 1; |
Damien Miller | 62116dc | 2001-12-24 01:41:47 +1100 | [diff] [blame] | 919 | } |
Darren Tucker | 7b48d25 | 2005-02-16 13:20:07 +1100 | [diff] [blame] | 920 | |
| 921 | /* |
| 922 | * We may attempt to re-seed during mkstemp if we are using the one in the |
Darren Tucker | 7a8619a | 2005-02-16 13:32:30 +1100 | [diff] [blame] | 923 | * compat library (via mkstemp -> _gettemp -> arc4random -> seed_rng) so we |
| 924 | * need our own seed_rng(). We must also check that we have enough entropy. |
Darren Tucker | 7b48d25 | 2005-02-16 13:20:07 +1100 | [diff] [blame] | 925 | */ |
| 926 | void |
| 927 | seed_rng(void) |
| 928 | { |
| 929 | if (!RAND_status()) |
| 930 | fatal("Not enough entropy in RNG"); |
| 931 | } |