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46aa3e0ce1
openbsd-compat/bindresvport.c openbsd-compat/getrrsetbyname.c openbsd-compat/port-tun.c openbsd-compat/rresvport.c] Include <arpa/inet.h> for hton* and ntoh* macros. Required on (at least) HP-UX since we define _XOPEN_SOURCE_EXTENDED. Found by santhi.amirta at gmail com.
925 lines
22 KiB
C
925 lines
22 KiB
C
/*
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* Copyright (c) 2001-2002 Damien Miller. All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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#include "includes.h"
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#include <sys/types.h>
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#include <sys/resource.h>
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#include <sys/stat.h>
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#include <sys/wait.h>
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#include <sys/socket.h>
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#include <stdarg.h>
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#include <stddef.h>
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#include <netinet/in.h>
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#include <arpa/inet.h>
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#ifdef HAVE_SYS_UN_H
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# include <sys/un.h>
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#endif
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#include <errno.h>
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#include <fcntl.h>
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#include <pwd.h>
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#include <signal.h>
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#include <time.h>
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#include <unistd.h>
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#include <openssl/rand.h>
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#include <openssl/sha.h>
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#include <openssl/crypto.h>
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/* SunOS 4.4.4 needs this */
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#ifdef HAVE_FLOATINGPOINT_H
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# include <floatingpoint.h>
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#endif /* HAVE_FLOATINGPOINT_H */
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#include "misc.h"
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#include "xmalloc.h"
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#include "atomicio.h"
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#include "pathnames.h"
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#include "log.h"
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/* Number of bytes we write out */
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#define OUTPUT_SEED_SIZE 48
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/* Length of on-disk seedfiles */
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#define SEED_FILE_SIZE 1024
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/* Maximum number of command-line arguments to read from file */
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#define NUM_ARGS 10
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/* Minimum number of usable commands to be considered sufficient */
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#define MIN_ENTROPY_SOURCES 16
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/* Path to on-disk seed file (relative to user's home directory */
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#ifndef SSH_PRNG_SEED_FILE
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# define SSH_PRNG_SEED_FILE _PATH_SSH_USER_DIR"/prng_seed"
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#endif
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/* Path to PRNG commands list */
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#ifndef SSH_PRNG_COMMAND_FILE
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# define SSH_PRNG_COMMAND_FILE SSHDIR "/ssh_prng_cmds"
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#endif
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extern char *__progname;
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#define WHITESPACE " \t\n"
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#ifndef RUSAGE_SELF
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# define RUSAGE_SELF 0
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#endif
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#ifndef RUSAGE_CHILDREN
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# define RUSAGE_CHILDREN 0
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#endif
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#if !defined(PRNGD_SOCKET) && !defined(PRNGD_PORT)
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# define USE_SEED_FILES
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#endif
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typedef struct {
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/* Proportion of data that is entropy */
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double rate;
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/* Counter goes positive if this command times out */
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unsigned int badness;
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/* Increases by factor of two each timeout */
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unsigned int sticky_badness;
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/* Path to executable */
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char *path;
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/* argv to pass to executable */
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char *args[NUM_ARGS]; /* XXX: arbitrary limit */
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/* full command string (debug) */
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char *cmdstring;
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} entropy_cmd_t;
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/* slow command timeouts (all in milliseconds) */
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/* static int entropy_timeout_default = ENTROPY_TIMEOUT_MSEC; */
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static int entropy_timeout_current = ENTROPY_TIMEOUT_MSEC;
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/* this is initialised from a file, by prng_read_commands() */
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static entropy_cmd_t *entropy_cmds = NULL;
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/* Prototypes */
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double stir_from_system(void);
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double stir_from_programs(void);
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double stir_gettimeofday(double entropy_estimate);
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double stir_clock(double entropy_estimate);
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double stir_rusage(int who, double entropy_estimate);
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double hash_command_output(entropy_cmd_t *src, unsigned char *hash);
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int get_random_bytes_prngd(unsigned char *buf, int len,
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unsigned short tcp_port, char *socket_path);
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/*
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* Collect 'len' bytes of entropy into 'buf' from PRNGD/EGD daemon
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* listening either on 'tcp_port', or via Unix domain socket at *
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* 'socket_path'.
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* Either a non-zero tcp_port or a non-null socket_path must be
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* supplied.
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* Returns 0 on success, -1 on error
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*/
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int
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get_random_bytes_prngd(unsigned char *buf, int len,
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unsigned short tcp_port, char *socket_path)
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{
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int fd, addr_len, rval, errors;
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u_char msg[2];
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struct sockaddr_storage addr;
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struct sockaddr_in *addr_in = (struct sockaddr_in *)&addr;
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struct sockaddr_un *addr_un = (struct sockaddr_un *)&addr;
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mysig_t old_sigpipe;
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/* Sanity checks */
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if (socket_path == NULL && tcp_port == 0)
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fatal("You must specify a port or a socket");
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if (socket_path != NULL &&
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strlen(socket_path) >= sizeof(addr_un->sun_path))
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fatal("Random pool path is too long");
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if (len <= 0 || len > 255)
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fatal("Too many bytes (%d) to read from PRNGD", len);
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memset(&addr, '\0', sizeof(addr));
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if (tcp_port != 0) {
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addr_in->sin_family = AF_INET;
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addr_in->sin_addr.s_addr = htonl(INADDR_LOOPBACK);
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addr_in->sin_port = htons(tcp_port);
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addr_len = sizeof(*addr_in);
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} else {
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addr_un->sun_family = AF_UNIX;
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strlcpy(addr_un->sun_path, socket_path,
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sizeof(addr_un->sun_path));
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addr_len = offsetof(struct sockaddr_un, sun_path) +
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strlen(socket_path) + 1;
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}
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old_sigpipe = mysignal(SIGPIPE, SIG_IGN);
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errors = 0;
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rval = -1;
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reopen:
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fd = socket(addr.ss_family, SOCK_STREAM, 0);
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if (fd == -1) {
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error("Couldn't create socket: %s", strerror(errno));
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goto done;
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}
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if (connect(fd, (struct sockaddr*)&addr, addr_len) == -1) {
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if (tcp_port != 0) {
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error("Couldn't connect to PRNGD port %d: %s",
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tcp_port, strerror(errno));
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} else {
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error("Couldn't connect to PRNGD socket \"%s\": %s",
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addr_un->sun_path, strerror(errno));
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}
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goto done;
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}
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/* Send blocking read request to PRNGD */
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msg[0] = 0x02;
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msg[1] = len;
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if (atomicio(vwrite, fd, msg, sizeof(msg)) != sizeof(msg)) {
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if (errno == EPIPE && errors < 10) {
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close(fd);
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errors++;
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goto reopen;
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}
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error("Couldn't write to PRNGD socket: %s",
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strerror(errno));
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goto done;
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}
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if (atomicio(read, fd, buf, len) != (size_t)len) {
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if (errno == EPIPE && errors < 10) {
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close(fd);
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errors++;
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goto reopen;
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}
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error("Couldn't read from PRNGD socket: %s",
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strerror(errno));
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goto done;
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}
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rval = 0;
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done:
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mysignal(SIGPIPE, old_sigpipe);
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if (fd != -1)
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close(fd);
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return rval;
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}
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static int
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seed_from_prngd(unsigned char *buf, size_t bytes)
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{
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#ifdef PRNGD_PORT
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debug("trying egd/prngd port %d", PRNGD_PORT);
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if (get_random_bytes_prngd(buf, bytes, PRNGD_PORT, NULL) == 0)
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return 0;
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#endif
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#ifdef PRNGD_SOCKET
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debug("trying egd/prngd socket %s", PRNGD_SOCKET);
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if (get_random_bytes_prngd(buf, bytes, 0, PRNGD_SOCKET) == 0)
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return 0;
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#endif
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return -1;
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}
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double
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stir_gettimeofday(double entropy_estimate)
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{
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struct timeval tv;
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if (gettimeofday(&tv, NULL) == -1)
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fatal("Couldn't gettimeofday: %s", strerror(errno));
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RAND_add(&tv, sizeof(tv), entropy_estimate);
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return entropy_estimate;
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}
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double
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stir_clock(double entropy_estimate)
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{
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#ifdef HAVE_CLOCK
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clock_t c;
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c = clock();
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RAND_add(&c, sizeof(c), entropy_estimate);
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return entropy_estimate;
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#else /* _HAVE_CLOCK */
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return 0;
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#endif /* _HAVE_CLOCK */
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}
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double
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stir_rusage(int who, double entropy_estimate)
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{
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#ifdef HAVE_GETRUSAGE
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struct rusage ru;
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if (getrusage(who, &ru) == -1)
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return 0;
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RAND_add(&ru, sizeof(ru), entropy_estimate);
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return entropy_estimate;
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#else /* _HAVE_GETRUSAGE */
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return 0;
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#endif /* _HAVE_GETRUSAGE */
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}
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static int
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timeval_diff(struct timeval *t1, struct timeval *t2)
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{
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int secdiff, usecdiff;
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secdiff = t2->tv_sec - t1->tv_sec;
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usecdiff = (secdiff*1000000) + (t2->tv_usec - t1->tv_usec);
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return (int)(usecdiff / 1000);
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}
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double
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hash_command_output(entropy_cmd_t *src, unsigned char *hash)
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{
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char buf[8192];
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fd_set rdset;
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int bytes_read, cmd_eof, error_abort, msec_elapsed, p[2];
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int status, total_bytes_read;
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static int devnull = -1;
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pid_t pid;
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SHA_CTX sha;
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struct timeval tv_start, tv_current;
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debug3("Reading output from \'%s\'", src->cmdstring);
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if (devnull == -1) {
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devnull = open("/dev/null", O_RDWR);
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if (devnull == -1)
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fatal("Couldn't open /dev/null: %s",
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strerror(errno));
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}
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if (pipe(p) == -1)
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fatal("Couldn't open pipe: %s", strerror(errno));
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(void)gettimeofday(&tv_start, NULL); /* record start time */
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switch (pid = fork()) {
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case -1: /* Error */
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close(p[0]);
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close(p[1]);
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fatal("Couldn't fork: %s", strerror(errno));
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/* NOTREACHED */
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case 0: /* Child */
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dup2(devnull, STDIN_FILENO);
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dup2(p[1], STDOUT_FILENO);
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dup2(p[1], STDERR_FILENO);
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close(p[0]);
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close(p[1]);
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close(devnull);
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execv(src->path, (char**)(src->args));
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debug("(child) Couldn't exec '%s': %s",
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src->cmdstring, strerror(errno));
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_exit(-1);
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default: /* Parent */
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break;
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}
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RAND_add(&pid, sizeof(&pid), 0.0);
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close(p[1]);
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/* Hash output from child */
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SHA1_Init(&sha);
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cmd_eof = error_abort = msec_elapsed = total_bytes_read = 0;
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while (!error_abort && !cmd_eof) {
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int ret;
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struct timeval tv;
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int msec_remaining;
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(void) gettimeofday(&tv_current, 0);
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msec_elapsed = timeval_diff(&tv_start, &tv_current);
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if (msec_elapsed >= entropy_timeout_current) {
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error_abort=1;
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continue;
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}
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msec_remaining = entropy_timeout_current - msec_elapsed;
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FD_ZERO(&rdset);
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FD_SET(p[0], &rdset);
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tv.tv_sec = msec_remaining / 1000;
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tv.tv_usec = (msec_remaining % 1000) * 1000;
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ret = select(p[0] + 1, &rdset, NULL, NULL, &tv);
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RAND_add(&tv, sizeof(tv), 0.0);
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switch (ret) {
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case 0:
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/* timer expired */
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error_abort = 1;
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kill(pid, SIGINT);
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break;
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case 1:
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/* command input */
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do {
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bytes_read = read(p[0], buf, sizeof(buf));
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} while (bytes_read == -1 && errno == EINTR);
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RAND_add(&bytes_read, sizeof(&bytes_read), 0.0);
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if (bytes_read == -1) {
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error_abort = 1;
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break;
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} else if (bytes_read) {
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SHA1_Update(&sha, buf, bytes_read);
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total_bytes_read += bytes_read;
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} else {
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cmd_eof = 1;
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}
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break;
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case -1:
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default:
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/* error */
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debug("Command '%s': select() failed: %s",
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src->cmdstring, strerror(errno));
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error_abort = 1;
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break;
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}
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}
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SHA1_Final(hash, &sha);
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close(p[0]);
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debug3("Time elapsed: %d msec", msec_elapsed);
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if (waitpid(pid, &status, 0) == -1) {
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error("Couldn't wait for child '%s' completion: %s",
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src->cmdstring, strerror(errno));
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return 0.0;
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}
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RAND_add(&status, sizeof(&status), 0.0);
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if (error_abort) {
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/*
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* Closing p[0] on timeout causes the entropy command to
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* SIGPIPE. Take whatever output we got, and mark this
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* command as slow
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*/
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debug2("Command '%s' timed out", src->cmdstring);
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src->sticky_badness *= 2;
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src->badness = src->sticky_badness;
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return total_bytes_read;
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}
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if (WIFEXITED(status)) {
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if (WEXITSTATUS(status) == 0) {
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return total_bytes_read;
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} else {
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debug2("Command '%s' exit status was %d",
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src->cmdstring, WEXITSTATUS(status));
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src->badness = src->sticky_badness = 128;
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return 0.0;
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}
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} else if (WIFSIGNALED(status)) {
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debug2("Command '%s' returned on uncaught signal %d !",
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src->cmdstring, status);
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src->badness = src->sticky_badness = 128;
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return 0.0;
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} else
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return 0.0;
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}
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double
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stir_from_system(void)
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{
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double total_entropy_estimate;
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long int i;
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total_entropy_estimate = 0;
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i = getpid();
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RAND_add(&i, sizeof(i), 0.5);
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total_entropy_estimate += 0.1;
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i = getppid();
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RAND_add(&i, sizeof(i), 0.5);
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total_entropy_estimate += 0.1;
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i = getuid();
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RAND_add(&i, sizeof(i), 0.0);
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i = getgid();
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RAND_add(&i, sizeof(i), 0.0);
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total_entropy_estimate += stir_gettimeofday(1.0);
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total_entropy_estimate += stir_clock(0.5);
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total_entropy_estimate += stir_rusage(RUSAGE_SELF, 2.0);
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return total_entropy_estimate;
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}
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double
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stir_from_programs(void)
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{
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int c;
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double entropy, total_entropy;
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unsigned char hash[SHA_DIGEST_LENGTH];
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total_entropy = 0;
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for(c = 0; entropy_cmds[c].path != NULL; c++) {
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if (!entropy_cmds[c].badness) {
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/* Hash output from command */
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entropy = hash_command_output(&entropy_cmds[c],
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hash);
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/* Scale back estimate by command's rate */
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entropy *= entropy_cmds[c].rate;
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/* Upper bound of entropy is SHA_DIGEST_LENGTH */
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if (entropy > SHA_DIGEST_LENGTH)
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entropy = SHA_DIGEST_LENGTH;
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/* Stir it in */
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RAND_add(hash, sizeof(hash), entropy);
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debug3("Got %0.2f bytes of entropy from '%s'",
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entropy, entropy_cmds[c].cmdstring);
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total_entropy += entropy;
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/* Execution time should be a bit unpredictable */
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total_entropy += stir_gettimeofday(0.05);
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total_entropy += stir_clock(0.05);
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total_entropy += stir_rusage(RUSAGE_SELF, 0.1);
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total_entropy += stir_rusage(RUSAGE_CHILDREN, 0.1);
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|
} 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;
|
|
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();
|
|
}
|
|
}
|
|
|
|
log_init(argv[0], ll, SYSLOG_FACILITY_USER, 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");
|
|
}
|