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-rw-r--r--ssh-rand-helper.c932
1 files changed, 0 insertions, 932 deletions
diff --git a/ssh-rand-helper.c b/ssh-rand-helper.c
deleted file mode 100644
index fa507049..00000000
--- a/ssh-rand-helper.c
+++ /dev/null
@@ -1,932 +0,0 @@
-/*
- * Copyright (c) 2001-2002 Damien Miller. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
- * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
- * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
- * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
- * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#include "includes.h"
-
-#include <sys/types.h>
-#include <sys/resource.h>
-#include <sys/stat.h>
-#include <sys/wait.h>
-#include <sys/socket.h>
-
-#include <stdarg.h>
-#include <stddef.h>
-#include <string.h>
-
-#include <netinet/in.h>
-#include <arpa/inet.h>
-
-#ifdef HAVE_SYS_UN_H
-# include <sys/un.h>
-#endif
-
-#include <errno.h>
-#include <fcntl.h>
-#include <pwd.h>
-#include <signal.h>
-#include <time.h>
-#include <unistd.h>
-
-#include <openssl/rand.h>
-#include <openssl/sha.h>
-#include <openssl/crypto.h>
-
-/* SunOS 4.4.4 needs this */
-#ifdef HAVE_FLOATINGPOINT_H
-# include <floatingpoint.h>
-#endif /* HAVE_FLOATINGPOINT_H */
-
-#include "misc.h"
-#include "xmalloc.h"
-#include "atomicio.h"
-#include "pathnames.h"
-#include "log.h"
-
-/* Number of bytes we write out */
-#define OUTPUT_SEED_SIZE 48
-
-/* Length of on-disk seedfiles */
-#define SEED_FILE_SIZE 1024
-
-/* Maximum number of command-line arguments to read from file */
-#define NUM_ARGS 10
-
-/* Minimum number of usable commands to be considered sufficient */
-#define MIN_ENTROPY_SOURCES 16
-
-/* Path to on-disk seed file (relative to user's home directory */
-#ifndef SSH_PRNG_SEED_FILE
-# define SSH_PRNG_SEED_FILE _PATH_SSH_USER_DIR"/prng_seed"
-#endif
-
-/* Path to PRNG commands list */
-#ifndef SSH_PRNG_COMMAND_FILE
-# define SSH_PRNG_COMMAND_FILE SSHDIR "/ssh_prng_cmds"
-#endif
-
-extern char *__progname;
-
-#define WHITESPACE " \t\n"
-
-#ifndef RUSAGE_SELF
-# define RUSAGE_SELF 0
-#endif
-#ifndef RUSAGE_CHILDREN
-# define RUSAGE_CHILDREN 0
-#endif
-
-#if !defined(PRNGD_SOCKET) && !defined(PRNGD_PORT)
-# define USE_SEED_FILES
-#endif
-
-typedef struct {
- /* Proportion of data that is entropy */
- double rate;
- /* Counter goes positive if this command times out */
- unsigned int badness;
- /* Increases by factor of two each timeout */
- unsigned int sticky_badness;
- /* Path to executable */
- char *path;
- /* argv to pass to executable */
- char *args[NUM_ARGS]; /* XXX: arbitrary limit */
- /* full command string (debug) */
- char *cmdstring;
-} entropy_cmd_t;
-
-/* slow command timeouts (all in milliseconds) */
-/* static int entropy_timeout_default = ENTROPY_TIMEOUT_MSEC; */
-static int entropy_timeout_current = ENTROPY_TIMEOUT_MSEC;
-
-/* this is initialised from a file, by prng_read_commands() */
-static entropy_cmd_t *entropy_cmds = NULL;
-
-/* Prototypes */
-double stir_from_system(void);
-double stir_from_programs(void);
-double stir_gettimeofday(double entropy_estimate);
-double stir_clock(double entropy_estimate);
-double stir_rusage(int who, double entropy_estimate);
-double hash_command_output(entropy_cmd_t *src, unsigned char *hash);
-int get_random_bytes_prngd(unsigned char *buf, int len,
- unsigned short tcp_port, char *socket_path);
-
-/*
- * Collect 'len' bytes of entropy into 'buf' from PRNGD/EGD daemon
- * listening either on 'tcp_port', or via Unix domain socket at *
- * 'socket_path'.
- * Either a non-zero tcp_port or a non-null socket_path must be
- * supplied.
- * Returns 0 on success, -1 on error
- */
-int
-get_random_bytes_prngd(unsigned char *buf, int len,
- unsigned short tcp_port, char *socket_path)
-{
- int fd, addr_len, rval, errors;
- u_char msg[2];
- struct sockaddr_storage addr;
- struct sockaddr_in *addr_in = (struct sockaddr_in *)&addr;
- struct sockaddr_un *addr_un = (struct sockaddr_un *)&addr;
- mysig_t old_sigpipe;
-
- /* Sanity checks */
- if (socket_path == NULL && tcp_port == 0)
- fatal("You must specify a port or a socket");
- if (socket_path != NULL &&
- strlen(socket_path) >= sizeof(addr_un->sun_path))
- fatal("Random pool path is too long");
- if (len <= 0 || len > 255)
- fatal("Too many bytes (%d) to read from PRNGD", len);
-
- memset(&addr, '\0', sizeof(addr));
-
- if (tcp_port != 0) {
- addr_in->sin_family = AF_INET;
- addr_in->sin_addr.s_addr = htonl(INADDR_LOOPBACK);
- addr_in->sin_port = htons(tcp_port);
- addr_len = sizeof(*addr_in);
- } else {
- addr_un->sun_family = AF_UNIX;
- strlcpy(addr_un->sun_path, socket_path,
- sizeof(addr_un->sun_path));
- addr_len = offsetof(struct sockaddr_un, sun_path) +
- strlen(socket_path) + 1;
- }
-
- old_sigpipe = mysignal(SIGPIPE, SIG_IGN);
-
- errors = 0;
- rval = -1;
-reopen:
- fd = socket(addr.ss_family, SOCK_STREAM, 0);
- if (fd == -1) {
- error("Couldn't create socket: %s", strerror(errno));
- goto done;
- }
-
- if (connect(fd, (struct sockaddr*)&addr, addr_len) == -1) {
- if (tcp_port != 0) {
- error("Couldn't connect to PRNGD port %d: %s",
- tcp_port, strerror(errno));
- } else {
- error("Couldn't connect to PRNGD socket \"%s\": %s",
- addr_un->sun_path, strerror(errno));
- }
- goto done;
- }
-
- /* Send blocking read request to PRNGD */
- msg[0] = 0x02;
- msg[1] = len;
-
- if (atomicio(vwrite, fd, msg, sizeof(msg)) != sizeof(msg)) {
- if (errno == EPIPE && errors < 10) {
- close(fd);
- errors++;
- goto reopen;
- }
- error("Couldn't write to PRNGD socket: %s",
- strerror(errno));
- goto done;
- }
-
- if (atomicio(read, fd, buf, len) != (size_t)len) {
- if (errno == EPIPE && errors < 10) {
- close(fd);
- errors++;
- goto reopen;
- }
- error("Couldn't read from PRNGD socket: %s",
- strerror(errno));
- goto done;
- }
-
- rval = 0;
-done:
- mysignal(SIGPIPE, old_sigpipe);
- if (fd != -1)
- close(fd);
- return rval;
-}
-
-static int
-seed_from_prngd(unsigned char *buf, size_t bytes)
-{
-#ifdef PRNGD_PORT
- debug("trying egd/prngd port %d", PRNGD_PORT);
- if (get_random_bytes_prngd(buf, bytes, PRNGD_PORT, NULL) == 0)
- return 0;
-#endif
-#ifdef PRNGD_SOCKET
- debug("trying egd/prngd socket %s", PRNGD_SOCKET);
- if (get_random_bytes_prngd(buf, bytes, 0, PRNGD_SOCKET) == 0)
- return 0;
-#endif
- return -1;
-}
-
-double
-stir_gettimeofday(double entropy_estimate)
-{
- struct timeval tv;
-
- if (gettimeofday(&tv, NULL) == -1)
- fatal("Couldn't gettimeofday: %s", strerror(errno));
-
- RAND_add(&tv, sizeof(tv), entropy_estimate);
-
- return entropy_estimate;
-}
-
-double
-stir_clock(double entropy_estimate)
-{
-#ifdef HAVE_CLOCK
- clock_t c;
-
- c = clock();
- RAND_add(&c, sizeof(c), entropy_estimate);
-
- return entropy_estimate;
-#else /* _HAVE_CLOCK */
- return 0;
-#endif /* _HAVE_CLOCK */
-}
-
-double
-stir_rusage(int who, double entropy_estimate)
-{
-#ifdef HAVE_GETRUSAGE
- struct rusage ru;
-
- if (getrusage(who, &ru) == -1)
- return 0;
-
- RAND_add(&ru, sizeof(ru), entropy_estimate);
-
- return entropy_estimate;
-#else /* _HAVE_GETRUSAGE */
- return 0;
-#endif /* _HAVE_GETRUSAGE */
-}
-
-static int
-timeval_diff(struct timeval *t1, struct timeval *t2)
-{
- int secdiff, usecdiff;
-
- secdiff = t2->tv_sec - t1->tv_sec;
- usecdiff = (secdiff*1000000) + (t2->tv_usec - t1->tv_usec);
- return (int)(usecdiff / 1000);
-}
-
-double
-hash_command_output(entropy_cmd_t *src, unsigned char *hash)
-{
- char buf[8192];
- fd_set rdset;
- int bytes_read, cmd_eof, error_abort, msec_elapsed, p[2];
- int status, total_bytes_read;
- static int devnull = -1;
- pid_t pid;
- SHA_CTX sha;
- struct timeval tv_start, tv_current;
-
- debug3("Reading output from \'%s\'", src->cmdstring);
-
- if (devnull == -1) {
- devnull = open("/dev/null", O_RDWR);
- if (devnull == -1)
- fatal("Couldn't open /dev/null: %s",
- strerror(errno));
- }
-
- if (pipe(p) == -1)
- fatal("Couldn't open pipe: %s", strerror(errno));
-
- (void)gettimeofday(&tv_start, NULL); /* record start time */
-
- switch (pid = fork()) {
- case -1: /* Error */
- close(p[0]);
- close(p[1]);
- fatal("Couldn't fork: %s", strerror(errno));
- /* NOTREACHED */
- case 0: /* Child */
- dup2(devnull, STDIN_FILENO);
- dup2(p[1], STDOUT_FILENO);
- dup2(p[1], STDERR_FILENO);
- close(p[0]);
- close(p[1]);
- close(devnull);
-
- execv(src->path, (char**)(src->args));
-
- debug("(child) Couldn't exec '%s': %s",
- src->cmdstring, strerror(errno));
- _exit(-1);
- default: /* Parent */
- break;
- }
-
- RAND_add(&pid, sizeof(&pid), 0.0);
-
- close(p[1]);
-
- /* Hash output from child */
- SHA1_Init(&sha);
-
- cmd_eof = error_abort = msec_elapsed = total_bytes_read = 0;
- while (!error_abort && !cmd_eof) {
- int ret;
- struct timeval tv;
- int msec_remaining;
-
- (void) gettimeofday(&tv_current, 0);
- msec_elapsed = timeval_diff(&tv_start, &tv_current);
- if (msec_elapsed >= entropy_timeout_current) {
- error_abort=1;
- continue;
- }
- msec_remaining = entropy_timeout_current - msec_elapsed;
-
- FD_ZERO(&rdset);
- FD_SET(p[0], &rdset);
- tv.tv_sec = msec_remaining / 1000;
- tv.tv_usec = (msec_remaining % 1000) * 1000;
-
- ret = select(p[0] + 1, &rdset, NULL, NULL, &tv);
-
- RAND_add(&tv, sizeof(tv), 0.0);
-
- switch (ret) {
- case 0:
- /* timer expired */
- error_abort = 1;
- kill(pid, SIGINT);
- break;
- case 1:
- /* command input */
- do {
- bytes_read = read(p[0], buf, sizeof(buf));
- } while (bytes_read == -1 && errno == EINTR);
- RAND_add(&bytes_read, sizeof(&bytes_read), 0.0);
- if (bytes_read == -1) {
- error_abort = 1;
- break;
- } else if (bytes_read) {
- SHA1_Update(&sha, buf, bytes_read);
- total_bytes_read += bytes_read;
- } else {
- cmd_eof = 1;
- }
- break;
- case -1:
- default:
- /* error */
- debug("Command '%s': select() failed: %s",
- src->cmdstring, strerror(errno));
- error_abort = 1;
- break;
- }
- }
-
- SHA1_Final(hash, &sha);
-
- close(p[0]);
-
- debug3("Time elapsed: %d msec", msec_elapsed);
-
- if (waitpid(pid, &status, 0) == -1) {
- error("Couldn't wait for child '%s' completion: %s",
- src->cmdstring, strerror(errno));
- return 0.0;
- }
-
- RAND_add(&status, sizeof(&status), 0.0);
-
- if (error_abort) {
- /*
- * Closing p[0] on timeout causes the entropy command to
- * SIGPIPE. Take whatever output we got, and mark this
- * command as slow
- */
- debug2("Command '%s' timed out", src->cmdstring);
- src->sticky_badness *= 2;
- src->badness = src->sticky_badness;
- return total_bytes_read;
- }
-
- if (WIFEXITED(status)) {
- if (WEXITSTATUS(status) == 0) {
- return total_bytes_read;
- } else {
- debug2("Command '%s' exit status was %d",
- src->cmdstring, WEXITSTATUS(status));
- src->badness = src->sticky_badness = 128;
- return 0.0;
- }
- } else if (WIFSIGNALED(status)) {
- debug2("Command '%s' returned on uncaught signal %d !",
- src->cmdstring, status);
- src->badness = src->sticky_badness = 128;
- return 0.0;
- } else
- return 0.0;
-}
-
-double
-stir_from_system(void)
-{
- double total_entropy_estimate;
- long int i;
-
- total_entropy_estimate = 0;
-
- i = getpid();
- RAND_add(&i, sizeof(i), 0.5);
- total_entropy_estimate += 0.1;
-
- i = getppid();
- RAND_add(&i, sizeof(i), 0.5);
- total_entropy_estimate += 0.1;
-
- i = getuid();
- RAND_add(&i, sizeof(i), 0.0);
- i = getgid();
- RAND_add(&i, sizeof(i), 0.0);
-
- total_entropy_estimate += stir_gettimeofday(1.0);
- total_entropy_estimate += stir_clock(0.5);
- total_entropy_estimate += stir_rusage(RUSAGE_SELF, 2.0);
-
- return total_entropy_estimate;
-}
-
-double
-stir_from_programs(void)
-{
- int c;
- double entropy, total_entropy;
- unsigned char hash[SHA_DIGEST_LENGTH];
-
- total_entropy = 0;
- for(c = 0; entropy_cmds[c].path != NULL; c++) {
- if (!entropy_cmds[c].badness) {
- /* Hash output from command */
- entropy = hash_command_output(&entropy_cmds[c],
- hash);
-
- /* Scale back estimate by command's rate */
- entropy *= entropy_cmds[c].rate;
-
- /* Upper bound of entropy is SHA_DIGEST_LENGTH */
- if (entropy > SHA_DIGEST_LENGTH)
- entropy = SHA_DIGEST_LENGTH;
-
- /* Stir it in */
- RAND_add(hash, sizeof(hash), entropy);
-
- debug3("Got %0.2f bytes of entropy from '%s'",
- entropy, entropy_cmds[c].cmdstring);
-
- total_entropy += entropy;
-
- /* Execution time should be a bit unpredictable */
- total_entropy += stir_gettimeofday(0.05);
- total_entropy += stir_clock(0.05);
- total_entropy += stir_rusage(RUSAGE_SELF, 0.1);
- total_entropy += stir_rusage(RUSAGE_CHILDREN, 0.1);
- } else {
- debug2("Command '%s' disabled (badness %d)",
- entropy_cmds[c].cmdstring,
- entropy_cmds[c].badness);
-
- if (entropy_cmds[c].badness > 0)
- entropy_cmds[c].badness--;
- }
- }
-
- return total_entropy;
-}
-
-/*
- * prng seedfile functions
- */
-int
-prng_check_seedfile(char *filename)
-{
- struct stat st;
-
- /*
- * XXX raceable: eg replace seed between this stat and subsequent
- * open. Not such a problem because we don't really trust the
- * seed file anyway.
- * XXX: use secure path checking as elsewhere in OpenSSH
- */
- if (lstat(filename, &st) == -1) {
- /* Give up on hard errors */
- if (errno != ENOENT)
- debug("WARNING: Couldn't stat random seed file "
- "\"%.100s\": %s", filename, strerror(errno));
- return 0;
- }
-
- /* regular file? */
- if (!S_ISREG(st.st_mode))
- fatal("PRNG seedfile %.100s is not a regular file",
- filename);
-
- /* mode 0600, owned by root or the current user? */
- if (((st.st_mode & 0177) != 0) || !(st.st_uid == getuid())) {
- debug("WARNING: PRNG seedfile %.100s must be mode 0600, "
- "owned by uid %li", filename, (long int)getuid());
- return 0;
- }
-
- return 1;
-}
-
-void
-prng_write_seedfile(void)
-{
- int fd, save_errno;
- unsigned char seed[SEED_FILE_SIZE];
- char filename[MAXPATHLEN], tmpseed[MAXPATHLEN];
- struct passwd *pw;
- mode_t old_umask;
-
- pw = getpwuid(getuid());
- if (pw == NULL)
- fatal("Couldn't get password entry for current user "
- "(%li): %s", (long int)getuid(), strerror(errno));
-
- /* Try to ensure that the parent directory is there */
- snprintf(filename, sizeof(filename), "%.512s/%s", pw->pw_dir,
- _PATH_SSH_USER_DIR);
- if (mkdir(filename, 0700) < 0 && errno != EEXIST)
- fatal("mkdir %.200s: %s", filename, strerror(errno));
-
- snprintf(filename, sizeof(filename), "%.512s/%s", pw->pw_dir,
- SSH_PRNG_SEED_FILE);
-
- strlcpy(tmpseed, filename, sizeof(tmpseed));
- if (strlcat(tmpseed, ".XXXXXXXXXX", sizeof(tmpseed)) >=
- sizeof(tmpseed))
- fatal("PRNG seed filename too long");
-
- if (RAND_bytes(seed, sizeof(seed)) <= 0)
- fatal("PRNG seed extraction failed");
-
- /* Don't care if the seed doesn't exist */
- prng_check_seedfile(filename);
-
- old_umask = umask(0177);
-
- if ((fd = mkstemp(tmpseed)) == -1) {
- debug("WARNING: couldn't make temporary PRNG seedfile %.100s "
- "(%.100s)", tmpseed, strerror(errno));
- } else {
- debug("writing PRNG seed to file %.100s", tmpseed);
- if (atomicio(vwrite, fd, &seed, sizeof(seed)) < sizeof(seed)) {
- save_errno = errno;
- close(fd);
- unlink(tmpseed);
- fatal("problem writing PRNG seedfile %.100s "
- "(%.100s)", filename, strerror(save_errno));
- }
- close(fd);
- debug("moving temporary PRNG seed to file %.100s", filename);
- if (rename(tmpseed, filename) == -1) {
- save_errno = errno;
- unlink(tmpseed);
- fatal("problem renaming PRNG seedfile from %.100s "
- "to %.100s (%.100s)", tmpseed, filename,
- strerror(save_errno));
- }
- }
- umask(old_umask);
-}
-
-void
-prng_read_seedfile(void)
-{
- int fd;
- char seed[SEED_FILE_SIZE], filename[MAXPATHLEN];
- struct passwd *pw;
-
- pw = getpwuid(getuid());
- if (pw == NULL)
- fatal("Couldn't get password entry for current user "
- "(%li): %s", (long int)getuid(), strerror(errno));
-
- snprintf(filename, sizeof(filename), "%.512s/%s", pw->pw_dir,
- SSH_PRNG_SEED_FILE);
-
- debug("loading PRNG seed from file %.100s", filename);
-
- if (!prng_check_seedfile(filename)) {
- verbose("Random seed file not found or invalid, ignoring.");
- return;
- }
-
- /* open the file and read in the seed */
- fd = open(filename, O_RDONLY);
- if (fd == -1)
- fatal("could not open PRNG seedfile %.100s (%.100s)",
- filename, strerror(errno));
-
- if (atomicio(read, fd, &seed, sizeof(seed)) < sizeof(seed)) {
- verbose("invalid or short read from PRNG seedfile "
- "%.100s - ignoring", filename);
- memset(seed, '\0', sizeof(seed));
- }
- close(fd);
-
- /* stir in the seed, with estimated entropy zero */
- RAND_add(&seed, sizeof(seed), 0.0);
-}
-
-
-/*
- * entropy command initialisation functions
- */
-int
-prng_read_commands(char *cmdfilename)
-{
- char cmd[SEED_FILE_SIZE], *cp, line[1024], path[SEED_FILE_SIZE];
- double est;
- entropy_cmd_t *entcmd;
- FILE *f;
- int cur_cmd, linenum, num_cmds, arg;
-
- if ((f = fopen(cmdfilename, "r")) == NULL) {
- fatal("couldn't read entropy commands file %.100s: %.100s",
- cmdfilename, strerror(errno));
- }
-
- num_cmds = 64;
- entcmd = xcalloc(num_cmds, sizeof(entropy_cmd_t));
-
- /* Read in file */
- cur_cmd = linenum = 0;
- while (fgets(line, sizeof(line), f)) {
- linenum++;
-
- /* Skip leading whitespace, blank lines and comments */
- cp = line + strspn(line, WHITESPACE);
- if ((*cp == 0) || (*cp == '#'))
- continue; /* done with this line */
-
- /*
- * The first non-whitespace char should be a double quote
- * delimiting the commandline
- */
- if (*cp != '"') {
- error("bad entropy command, %.100s line %d",
- cmdfilename, linenum);
- continue;
- }
-
- /*
- * First token, command args (incl. argv[0]) in double
- * quotes
- */
- cp = strtok(cp, "\"");
- if (cp == NULL) {
- error("missing or bad command string, %.100s "
- "line %d -- ignored", cmdfilename, linenum);
- continue;
- }
- strlcpy(cmd, cp, sizeof(cmd));
-
- /* Second token, full command path */
- if ((cp = strtok(NULL, WHITESPACE)) == NULL) {
- error("missing command path, %.100s "
- "line %d -- ignored", cmdfilename, linenum);
- continue;
- }
-
- /* Did configure mark this as dead? */
- if (strncmp("undef", cp, 5) == 0)
- continue;
-
- strlcpy(path, cp, sizeof(path));
-
- /* Third token, entropy rate estimate for this command */
- if ((cp = strtok(NULL, WHITESPACE)) == NULL) {
- error("missing entropy estimate, %.100s "
- "line %d -- ignored", cmdfilename, linenum);
- continue;
- }
- est = strtod(cp, NULL);
-
- /* end of line */
- if ((cp = strtok(NULL, WHITESPACE)) != NULL) {
- error("garbage at end of line %d in %.100s "
- "-- ignored", linenum, cmdfilename);
- continue;
- }
-
- /* save the command for debug messages */
- entcmd[cur_cmd].cmdstring = xstrdup(cmd);
-
- /* split the command args */
- cp = strtok(cmd, WHITESPACE);
- arg = 0;
- do {
- entcmd[cur_cmd].args[arg] = xstrdup(cp);
- arg++;
- } while(arg < NUM_ARGS && (cp = strtok(NULL, WHITESPACE)));
-
- if (strtok(NULL, WHITESPACE))
- error("ignored extra commands (max %d), %.100s "
- "line %d", NUM_ARGS, cmdfilename, linenum);
-
- /* Copy the command path and rate estimate */
- entcmd[cur_cmd].path = xstrdup(path);
- entcmd[cur_cmd].rate = est;
-
- /* Initialise other values */
- entcmd[cur_cmd].sticky_badness = 1;
-
- cur_cmd++;
-
- /*
- * If we've filled the array, reallocate it twice the size
- * Do this now because even if this we're on the last
- * command we need another slot to mark the last entry
- */
- if (cur_cmd == num_cmds) {
- num_cmds *= 2;
- entcmd = xrealloc(entcmd, num_cmds,
- sizeof(entropy_cmd_t));
- }
- }
-
- /* zero the last entry */
- memset(&entcmd[cur_cmd], '\0', sizeof(entropy_cmd_t));
-
- /* trim to size */
- entropy_cmds = xrealloc(entcmd, (cur_cmd + 1),
- sizeof(entropy_cmd_t));
-
- debug("Loaded %d entropy commands from %.100s", cur_cmd,
- cmdfilename);
-
- fclose(f);
- return cur_cmd < MIN_ENTROPY_SOURCES ? -1 : 0;
-}
-
-void
-usage(void)
-{
- fprintf(stderr, "Usage: %s [options]\n", __progname);
- fprintf(stderr, " -v Verbose; display verbose debugging messages.\n");
- fprintf(stderr, " Multiple -v increases verbosity.\n");
- fprintf(stderr, " -x Force output in hexadecimal (for debugging)\n");
- fprintf(stderr, " -X Force output in binary\n");
- fprintf(stderr, " -b bytes Number of bytes to output (default %d)\n",
- OUTPUT_SEED_SIZE);
-}
-
-int
-main(int argc, char **argv)
-{
- unsigned char *buf;
- int ret, ch, debug_level, output_hex, bytes;
- extern char *optarg;
- extern int optind;
- LogLevel ll;
-
- __progname = ssh_get_progname(argv[0]);
- log_init(argv[0], SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_USER, 1);
-
- ll = SYSLOG_LEVEL_INFO;
- debug_level = output_hex = 0;
- bytes = OUTPUT_SEED_SIZE;
-
- /* Don't write binary data to a tty, unless we are forced to */
- if (isatty(STDOUT_FILENO))
- output_hex = 1;
-
- while ((ch = getopt(argc, argv, "vxXhb:")) != -1) {
- switch (ch) {
- case 'v':
- if (debug_level < 3)
- ll = SYSLOG_LEVEL_DEBUG1 + debug_level++;
- break;
- case 'x':
- output_hex = 1;
- break;
- case 'X':
- output_hex = 0;
- break;
- case 'b':
- if ((bytes = atoi(optarg)) <= 0)
- fatal("Invalid number of output bytes");
- break;
- case 'h':
- usage();
- exit(0);
- default:
- error("Invalid commandline option");
- usage();
- exit(1);
- }
- }
- log_init(argv[0], ll, SYSLOG_FACILITY_USER, 1);
-
- if (argc != optind) {
- error("Unexpected commandline arguments.");
- usage();
- exit(1);
- }
-
-#ifdef USE_SEED_FILES
- prng_read_seedfile();
-#endif
-
- buf = xmalloc(bytes);
-
- /*
- * Seed the RNG from wherever we can
- */
-
- /* Take whatever is on the stack, but don't credit it */
- RAND_add(buf, bytes, 0);
-
- debug("Seeded RNG with %i bytes from system calls",
- (int)stir_from_system());
-
- /* try prngd, fall back to commands if prngd fails or not configured */
- if (seed_from_prngd(buf, bytes) == 0) {
- RAND_add(buf, bytes, bytes);
- } else {
- /* Read in collection commands */
- if (prng_read_commands(SSH_PRNG_COMMAND_FILE) == -1)
- fatal("PRNG initialisation failed -- exiting.");
- debug("Seeded RNG with %i bytes from programs",
- (int)stir_from_programs());
- }
-
-#ifdef USE_SEED_FILES
- prng_write_seedfile();
-#endif
-
- /*
- * Write the seed to stdout
- */
-
- if (!RAND_status())
- fatal("Not enough entropy in RNG");
-
- if (RAND_bytes(buf, bytes) <= 0)
- fatal("Couldn't extract entropy from PRNG");
-
- if (output_hex) {
- for(ret = 0; ret < bytes; ret++)
- printf("%02x", (unsigned char)(buf[ret]));
- printf("\n");
- } else
- ret = atomicio(vwrite, STDOUT_FILENO, buf, bytes);
-
- memset(buf, '\0', bytes);
- xfree(buf);
-
- return ret == bytes ? 0 : 1;
-}
-
-/*
- * We may attempt to re-seed during mkstemp if we are using the one in the
- * compat library (via mkstemp -> _gettemp -> arc4random -> seed_rng) so we
- * need our own seed_rng(). We must also check that we have enough entropy.
- */
-void
-seed_rng(void)
-{
- if (!RAND_status())
- fatal("Not enough entropy in RNG");
-}