mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-27 11:55:06 +00:00
240 lines
6.4 KiB
C
240 lines
6.4 KiB
C
/*
|
|
* Copyright (c) 2001 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/socket.h>
|
|
#ifdef HAVE_SYS_UN_H
|
|
# include <sys/un.h>
|
|
#endif
|
|
|
|
#include <netinet/in.h>
|
|
#include <arpa/inet.h>
|
|
|
|
#include <errno.h>
|
|
#include <signal.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
#include <stddef.h> /* for offsetof */
|
|
|
|
#include <openssl/rand.h>
|
|
#include <openssl/crypto.h>
|
|
#include <openssl/err.h>
|
|
|
|
#include "ssh.h"
|
|
#include "misc.h"
|
|
#include "xmalloc.h"
|
|
#include "atomicio.h"
|
|
#include "pathnames.h"
|
|
#include "log.h"
|
|
#include "buffer.h"
|
|
|
|
/*
|
|
* Portable OpenSSH PRNG seeding:
|
|
* If OpenSSL has not "internally seeded" itself (e.g. pulled data from
|
|
* /dev/random), then collect RANDOM_SEED_SIZE bytes of randomness from
|
|
* PRNGd.
|
|
*/
|
|
#ifndef OPENSSL_PRNG_ONLY
|
|
|
|
#define RANDOM_SEED_SIZE 48
|
|
|
|
/*
|
|
* 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;
|
|
}
|
|
|
|
void
|
|
rexec_send_rng_seed(Buffer *m)
|
|
{
|
|
u_char buf[RANDOM_SEED_SIZE];
|
|
|
|
if (RAND_bytes(buf, sizeof(buf)) <= 0) {
|
|
error("Couldn't obtain random bytes (error %ld)",
|
|
ERR_get_error());
|
|
buffer_put_string(m, "", 0);
|
|
} else
|
|
buffer_put_string(m, buf, sizeof(buf));
|
|
}
|
|
|
|
void
|
|
rexec_recv_rng_seed(Buffer *m)
|
|
{
|
|
u_char *buf;
|
|
u_int len;
|
|
|
|
buf = buffer_get_string_ret(m, &len);
|
|
if (buf != NULL) {
|
|
debug3("rexec_recv_rng_seed: seeding rng with %u bytes", len);
|
|
RAND_add(buf, len, len);
|
|
}
|
|
}
|
|
#endif /* OPENSSL_PRNG_ONLY */
|
|
|
|
void
|
|
seed_rng(void)
|
|
{
|
|
#ifndef OPENSSL_PRNG_ONLY
|
|
unsigned char buf[RANDOM_SEED_SIZE];
|
|
#endif
|
|
/*
|
|
* OpenSSL version numbers: MNNFFPPS: major minor fix patch status
|
|
* We match major, minor, fix and status (not patch) for <1.0.0.
|
|
* After that, we acceptable compatible fix versions (so we
|
|
* allow 1.0.1 to work with 1.0.0). Going backwards is only allowed
|
|
* within a patch series.
|
|
*/
|
|
u_long version_mask = SSLeay() >= 0x1000000f ? ~0xffff0L : ~0xff0L;
|
|
if (((SSLeay() ^ OPENSSL_VERSION_NUMBER) & version_mask) ||
|
|
(SSLeay() >> 12) < (OPENSSL_VERSION_NUMBER >> 12))
|
|
fatal("OpenSSL version mismatch. Built against %lx, you "
|
|
"have %lx", (u_long)OPENSSL_VERSION_NUMBER, SSLeay());
|
|
|
|
#ifndef OPENSSL_PRNG_ONLY
|
|
if (RAND_status() == 1) {
|
|
debug3("RNG is ready, skipping seeding");
|
|
return;
|
|
}
|
|
|
|
if (seed_from_prngd(buf, sizeof(buf)) == -1)
|
|
fatal("Could not obtain seed from PRNGd");
|
|
RAND_add(buf, sizeof(buf), sizeof(buf));
|
|
memset(buf, '\0', sizeof(buf));
|
|
|
|
#endif /* OPENSSL_PRNG_ONLY */
|
|
if (RAND_status() != 1)
|
|
fatal("PRNG is not seeded");
|
|
}
|