*/
#include "includes.h"
-RCSID("$OpenBSD: sshd.c,v 1.239 2002/03/30 18:51:15 markus Exp $");
+RCSID("$OpenBSD: sshd.c,v 1.268 2003/06/04 10:23:48 djm Exp $");
#include <openssl/dh.h>
#include <openssl/bn.h>
#include <openssl/md5.h>
#include <openssl/rand.h>
+#ifdef HAVE_SECUREWARE
+#include <sys/security.h>
+#include <prot.h>
+#endif
#include "ssh.h"
#include "ssh1.h"
* Flag indicating whether IPv4 or IPv6. This can be set on the command line.
* Default value is AF_UNSPEC means both IPv4 and IPv6.
*/
-#ifdef IPV4_DEFAULT
-int IPv4or6 = AF_INET;
-#else
int IPv4or6 = AF_UNSPEC;
-#endif
/*
* Debug mode flag. This can be set on the command line. If debug
int startup_pipe; /* in child */
/* variables used for privilege separation */
-extern struct monitor *monitor;
-extern int use_privsep;
+int use_privsep;
+struct monitor *pmonitor;
/* Prototypes for various functions defined later in this file. */
void destroy_sensitive_data(void);
close_listen_socks(void)
{
int i;
+
for (i = 0; i < num_listen_socks; i++)
close(listen_socks[i]);
num_listen_socks = -1;
close_startup_pipes(void)
{
int i;
+
if (startup_pipes)
for (i = 0; i < options.max_startups; i++)
if (startup_pipes[i] != -1)
static void
sighup_restart(void)
{
- log("Received SIGHUP; restarting.");
+ logit("Received SIGHUP; restarting.");
close_listen_socks();
close_startup_pipes();
execv(saved_argv[0], saved_argv);
- log("RESTART FAILED: av[0]='%.100s', error: %.100s.", saved_argv[0], strerror(errno));
+ logit("RESTART FAILED: av[0]='%.100s', error: %.100s.", saved_argv[0],
+ strerror(errno));
exit(1);
}
static void
main_sigchld_handler(int sig)
{
- pid_t pid;
int save_errno = errno;
+ pid_t pid;
int status;
while ((pid = waitpid(-1, &status, WNOHANG)) > 0 ||
{
/* XXX no idea how fix this signal handler */
- /* Close the connection. */
- packet_close();
-
/* Log error and exit. */
- fatal("Timeout before authentication for %s.", get_remote_ipaddr());
+ fatal("Timeout before authentication for %s", get_remote_ipaddr());
}
/*
static void
generate_ephemeral_server_key(void)
{
- u_int32_t rand = 0;
+ u_int32_t rnd = 0;
int i;
verbose("Generating %s%d bit RSA key.",
for (i = 0; i < SSH_SESSION_KEY_LENGTH; i++) {
if (i % 4 == 0)
- rand = arc4random();
- sensitive_data.ssh1_cookie[i] = rand & 0xff;
- rand >>= 8;
+ rnd = arc4random();
+ sensitive_data.ssh1_cookie[i] = rnd & 0xff;
+ rnd >>= 8;
}
arc4random_stir();
}
key_regeneration_alarm(int sig)
{
int save_errno = errno;
+
signal(SIGALRM, SIG_DFL);
errno = save_errno;
key_do_regen = 1;
if (client_version_string == NULL) {
/* Send our protocol version identification. */
- if (atomicio(write, sock_out, server_version_string, strlen(server_version_string))
+ if (atomicio(write, sock_out, server_version_string,
+ strlen(server_version_string))
!= strlen(server_version_string)) {
- log("Could not write ident string to %s", get_remote_ipaddr());
+ logit("Could not write ident string to %s", get_remote_ipaddr());
fatal_cleanup();
}
- /* Read other side's version identification. */
+ /* Read other sides version identification. */
memset(buf, 0, sizeof(buf));
for (i = 0; i < sizeof(buf) - 1; i++) {
if (atomicio(read, sock_in, &buf[i], 1) != 1) {
- log("Did not receive identification string from %s",
+ logit("Did not receive identification string from %s",
get_remote_ipaddr());
fatal_cleanup();
}
(void) atomicio(write, sock_out, s, strlen(s));
close(sock_in);
close(sock_out);
- log("Bad protocol version identification '%.100s' from %s",
+ logit("Bad protocol version identification '%.100s' from %s",
client_version_string, get_remote_ipaddr());
fatal_cleanup();
}
compat_datafellows(remote_version);
+ if (datafellows & SSH_BUG_PROBE) {
+ logit("probed from %s with %s. Don't panic.",
+ get_remote_ipaddr(), client_version_string);
+ fatal_cleanup();
+ }
+
if (datafellows & SSH_BUG_SCANNER) {
- log("scanned from %s with %s. Don't panic.",
+ logit("scanned from %s with %s. Don't panic.",
get_remote_ipaddr(), client_version_string);
fatal_cleanup();
}
(void) atomicio(write, sock_out, s, strlen(s));
close(sock_in);
close(sock_out);
- log("Protocol major versions differ for %s: %.200s vs. %.200s",
+ logit("Protocol major versions differ for %s: %.200s vs. %.200s",
get_remote_ipaddr(),
server_version_string, client_version_string);
fatal_cleanup();
}
}
-
/* Destroy the host and server keys. They will no longer be needed. */
void
destroy_sensitive_data(void)
static void
privsep_preauth_child(void)
{
- u_int32_t rand[256];
- int i;
+ u_int32_t rnd[256];
+ gid_t gidset[1];
struct passwd *pw;
+ int i;
/* Enable challenge-response authentication for privilege separation */
privsep_challenge_enable();
for (i = 0; i < 256; i++)
- rand[i] = arc4random();
- RAND_seed(rand, sizeof(rand));
+ rnd[i] = arc4random();
+ RAND_seed(rnd, sizeof(rnd));
/* Demote the private keys to public keys. */
demote_sensitive_data();
if ((pw = getpwnam(SSH_PRIVSEP_USER)) == NULL)
- fatal("%s: no user", SSH_PRIVSEP_USER);
+ fatal("Privilege separation user %s does not exist",
+ SSH_PRIVSEP_USER);
memset(pw->pw_passwd, 0, strlen(pw->pw_passwd));
endpwent();
- /* Change our root directory*/
+ /* Change our root directory */
if (chroot(_PATH_PRIVSEP_CHROOT_DIR) == -1)
fatal("chroot(\"%s\"): %s", _PATH_PRIVSEP_CHROOT_DIR,
strerror(errno));
/* Drop our privileges */
debug3("privsep user:group %u:%u", (u_int)pw->pw_uid,
(u_int)pw->pw_gid);
+#if 0
+ /* XXX not ready, to heavy after chroot */
do_setusercontext(pw);
+#else
+ gidset[0] = pw->pw_gid;
+ if (setgroups(1, gidset) < 0)
+ fatal("setgroups: %.100s", strerror(errno));
+ permanently_set_uid(pw);
+#endif
}
-static Authctxt*
+static Authctxt *
privsep_preauth(void)
{
Authctxt *authctxt = NULL;
pid_t pid;
/* Set up unprivileged child process to deal with network data */
- monitor = monitor_init();
+ pmonitor = monitor_init();
/* Store a pointer to the kex for later rekeying */
- monitor->m_pkex = &xxx_kex;
+ pmonitor->m_pkex = &xxx_kex;
pid = fork();
if (pid == -1) {
fatal("fork of unprivileged child failed");
} else if (pid != 0) {
- debug2("Network child is on pid %d", pid);
+ fatal_remove_cleanup((void (*) (void *)) packet_close, NULL);
- close(monitor->m_recvfd);
- authctxt = monitor_child_preauth(monitor);
- close(monitor->m_sendfd);
+ debug2("Network child is on pid %ld", (long)pid);
+
+ close(pmonitor->m_recvfd);
+ authctxt = monitor_child_preauth(pmonitor);
+ close(pmonitor->m_sendfd);
/* Sync memory */
- monitor_sync(monitor);
+ monitor_sync(pmonitor);
/* Wait for the child's exit status */
while (waitpid(pid, &status, 0) < 0)
if (errno != EINTR)
break;
+
+ /* Reinstall, since the child has finished */
+ fatal_add_cleanup((void (*) (void *)) packet_close, NULL);
+
return (authctxt);
} else {
/* child */
- close(monitor->m_sendfd);
+ close(pmonitor->m_sendfd);
/* Demote the child */
if (getuid() == 0 || geteuid() == 0)
/* XXX - Remote port forwarding */
x_authctxt = authctxt;
+#ifdef DISABLE_FD_PASSING
+ if (1) {
+#else
if (authctxt->pw->pw_uid == 0 || options.use_login) {
+#endif
/* File descriptor passing is broken or root login */
- monitor_apply_keystate(monitor);
+ monitor_apply_keystate(pmonitor);
use_privsep = 0;
return;
}
}
/* New socket pair */
- monitor_reinit(monitor);
+ monitor_reinit(pmonitor);
- monitor->m_pid = fork();
- if (monitor->m_pid == -1)
+ pmonitor->m_pid = fork();
+ if (pmonitor->m_pid == -1)
fatal("fork of unprivileged child failed");
- else if (monitor->m_pid != 0) {
- debug2("User child is on pid %d", monitor->m_pid);
- close(monitor->m_recvfd);
- monitor_child_postauth(monitor);
+ else if (pmonitor->m_pid != 0) {
+ fatal_remove_cleanup((void (*) (void *)) packet_close, NULL);
+
+ debug2("User child is on pid %ld", (long)pmonitor->m_pid);
+ close(pmonitor->m_recvfd);
+ monitor_child_postauth(pmonitor);
/* NEVERREACHED */
exit(0);
}
- close(monitor->m_sendfd);
+ close(pmonitor->m_sendfd);
/* Demote the private keys to public keys. */
demote_sensitive_data();
do_setusercontext(authctxt->pw);
/* It is safe now to apply the key state */
- monitor_apply_keystate(monitor);
+ monitor_apply_keystate(pmonitor);
}
static char *
get_hostkey_by_type(int type)
{
int i;
+
for (i = 0; i < options.num_host_key_files; i++) {
Key *key = sensitive_data.host_keys[i];
if (key != NULL && key->type == type)
get_hostkey_index(Key *key)
{
int i;
+
for (i = 0; i < options.num_host_key_files; i++) {
if (key == sensitive_data.host_keys[i])
return (i);
const char *remote_ip;
int remote_port;
FILE *f;
- struct linger linger;
struct addrinfo *ai;
char ntop[NI_MAXHOST], strport[NI_MAXSERV];
int listen_sock, maxfd;
Key *key;
int ret, key_used = 0;
+#ifdef HAVE_SECUREWARE
+ (void)set_auth_parameters(ac, av);
+#endif
__progname = get_progname(av[0]);
init_rng();
- /* Save argv. */
+ /* Save argv. Duplicate so setproctitle emulation doesn't clobber it */
saved_argc = ac;
- saved_argv = av;
+ saved_argv = xmalloc(sizeof(*saved_argv) * (ac + 1));
+ for (i = 0; i < ac; i++)
+ saved_argv[i] = xstrdup(av[i]);
+ saved_argv[i] = NULL;
+
+#ifndef HAVE_SETPROCTITLE
+ /* Prepare for later setproctitle emulation */
+ compat_init_setproctitle(ac, av);
+ av = saved_argv;
+#endif
/* Initialize configuration options to their default values. */
initialize_server_options(&options);
break;
case 'u':
utmp_len = atoi(optarg);
+ if (utmp_len > MAXHOSTNAMELEN) {
+ fprintf(stderr, "Invalid utmp length.\n");
+ exit(1);
+ }
break;
case 'o':
if (process_server_config_line(&options, optarg,
SYSLOG_LEVEL_INFO : options.log_level,
options.log_facility == SYSLOG_FACILITY_NOT_SET ?
SYSLOG_FACILITY_AUTH : options.log_facility,
- !inetd_flag);
+ log_stderr || !inetd_flag);
-#ifdef _CRAY
+#ifdef _UNICOS
/* Cray can define user privs drop all prives now!
* Not needed on PRIV_SU systems!
*/
debug("sshd version %.100s", SSH_VERSION);
/* load private host keys */
- sensitive_data.host_keys = xmalloc(options.num_host_key_files*sizeof(Key*));
+ sensitive_data.host_keys = xmalloc(options.num_host_key_files *
+ sizeof(Key *));
for (i = 0; i < options.num_host_key_files; i++)
sensitive_data.host_keys[i] = NULL;
sensitive_data.server_key = NULL;
key_type(key));
}
if ((options.protocol & SSH_PROTO_1) && !sensitive_data.have_ssh1_key) {
- log("Disabling protocol version 1. Could not load host key");
+ logit("Disabling protocol version 1. Could not load host key");
options.protocol &= ~SSH_PROTO_1;
}
if ((options.protocol & SSH_PROTO_2) && !sensitive_data.have_ssh2_key) {
- log("Disabling protocol version 2. Could not load host key");
+ logit("Disabling protocol version 2. Could not load host key");
options.protocol &= ~SSH_PROTO_2;
}
if (!(options.protocol & (SSH_PROTO_1|SSH_PROTO_2))) {
- log("sshd: no hostkeys available -- exiting.");
+ logit("sshd: no hostkeys available -- exiting.");
exit(1);
}
* hate software patents. I dont know if this can go? Niels
*/
if (options.server_key_bits >
- BN_num_bits(sensitive_data.ssh1_host_key->rsa->n) - SSH_KEY_BITS_RESERVED &&
- options.server_key_bits <
- BN_num_bits(sensitive_data.ssh1_host_key->rsa->n) + SSH_KEY_BITS_RESERVED) {
+ BN_num_bits(sensitive_data.ssh1_host_key->rsa->n) -
+ SSH_KEY_BITS_RESERVED && options.server_key_bits <
+ BN_num_bits(sensitive_data.ssh1_host_key->rsa->n) +
+ SSH_KEY_BITS_RESERVED) {
options.server_key_bits =
- BN_num_bits(sensitive_data.ssh1_host_key->rsa->n) + SSH_KEY_BITS_RESERVED;
+ BN_num_bits(sensitive_data.ssh1_host_key->rsa->n) +
+ SSH_KEY_BITS_RESERVED;
debug("Forcing server key to %d bits to make it differ from host key.",
options.server_key_bits);
}
}
+ if (use_privsep) {
+ struct passwd *pw;
+ struct stat st;
+
+ if ((pw = getpwnam(SSH_PRIVSEP_USER)) == NULL)
+ fatal("Privilege separation user %s does not exist",
+ SSH_PRIVSEP_USER);
+ if ((stat(_PATH_PRIVSEP_CHROOT_DIR, &st) == -1) ||
+ (S_ISDIR(st.st_mode) == 0))
+ fatal("Missing privilege separation directory: %s",
+ _PATH_PRIVSEP_CHROOT_DIR);
+
+#ifdef HAVE_CYGWIN
+ if (check_ntsec(_PATH_PRIVSEP_CHROOT_DIR) &&
+ (st.st_uid != getuid () ||
+ (st.st_mode & (S_IWGRP|S_IWOTH)) != 0))
+#else
+ if (st.st_uid != 0 || (st.st_mode & (S_IWGRP|S_IWOTH)) != 0)
+#endif
+ fatal("%s must be owned by root and not group or "
+ "world-writable.", _PATH_PRIVSEP_CHROOT_DIR);
+ }
+
/* Configuration looks good, so exit if in test mode. */
if (test_flag)
exit(0);
-#ifdef HAVE_SCO_PROTECTED_PW
- (void) set_auth_parameters(ac, av);
-#endif
+ /*
+ * Clear out any supplemental groups we may have inherited. This
+ * prevents inadvertent creation of files with bad modes (in the
+ * portable version at least, it's certainly possible for PAM
+ * to create a file, and we can't control the code in every
+ * module which might be used).
+ */
+ if (setgroups(0, NULL) < 0)
+ debug("setgroups() failed: %.200s", strerror(errno));
/* Initialize the log (it is reinitialized below in case we forked). */
if (debug_flag && !inetd_flag)
continue;
}
/* Create socket for listening. */
- listen_sock = socket(ai->ai_family, SOCK_STREAM, 0);
+ listen_sock = socket(ai->ai_family, ai->ai_socktype,
+ ai->ai_protocol);
if (listen_sock < 0) {
/* kernel may not support ipv6 */
verbose("socket: %.100s", strerror(errno));
continue;
}
/*
- * Set socket options. We try to make the port
- * reusable and have it close as fast as possible
- * without waiting in unnecessary wait states on
- * close.
+ * Set socket options.
+ * Allow local port reuse in TIME_WAIT.
*/
- setsockopt(listen_sock, SOL_SOCKET, SO_REUSEADDR,
- &on, sizeof(on));
- linger.l_onoff = 1;
- linger.l_linger = 5;
- setsockopt(listen_sock, SOL_SOCKET, SO_LINGER,
- &linger, sizeof(linger));
+ if (setsockopt(listen_sock, SOL_SOCKET, SO_REUSEADDR,
+ &on, sizeof(on)) == -1)
+ error("setsockopt SO_REUSEADDR: %s", strerror(errno));
debug("Bind to port %s on %s.", strport, ntop);
num_listen_socks++;
/* Start listening on the port. */
- log("Server listening on %s port %s.", ntop, strport);
+ logit("Server listening on %s port %s.", ntop, strport);
if (listen(listen_sock, 5) < 0)
fatal("listen: %.100s", strerror(errno));
*/
f = fopen(options.pid_file, "wb");
if (f) {
- fprintf(f, "%u\n", (u_int) getpid());
+ fprintf(f, "%ld\n", (long) getpid());
fclose(f);
}
}
if (ret < 0 && errno != EINTR)
error("select: %.100s", strerror(errno));
if (received_sigterm) {
- log("Received signal %d; terminating.",
+ logit("Received signal %d; terminating.",
(int) received_sigterm);
close_listen_socks();
unlink(options.pid_file);
if (pid < 0)
error("fork: %.100s", strerror(errno));
else
- debug("Forked child %d.", pid);
+ debug("Forked child %ld.", (long)pid);
close(startup_p[1]);
if ((options.protocol & SSH_PROTO_1) &&
key_used == 0) {
/* Schedule server key regeneration alarm. */
- signal(SIGALRM, key_regeneration_alarm);
+ mysignal(SIGALRM, key_regeneration_alarm);
alarm(options.key_regeneration_time);
key_used = 1;
}
/* This is the child processing a new connection. */
+ /*
+ * Create a new session and process group since the 4.4BSD
+ * setlogin() affects the entire process group. We don't
+ * want the child to be able to affect the parent.
+ */
+#if !defined(SSHD_ACQUIRES_CTTY)
+ /*
+ * If setsid is called, on some platforms sshd will later acquire a
+ * controlling terminal which will result in "could not set
+ * controlling tty" errors.
+ */
+ if (!debug_flag && !inetd_flag && setsid() < 0)
+ error("setsid: %.100s", strerror(errno));
+#endif
+
/*
* Disable the key regeneration alarm. We will not regenerate the
* key since we are no longer in a position to give it to anyone. We
signal(SIGCHLD, SIG_DFL);
signal(SIGINT, SIG_DFL);
- /*
- * Set socket options for the connection. We want the socket to
- * close as fast as possible without waiting for anything. If the
- * connection is not a socket, these will do nothing.
- */
- /* setsockopt(sock_in, SOL_SOCKET, SO_REUSEADDR, (void *)&on, sizeof(on)); */
- linger.l_onoff = 1;
- linger.l_linger = 5;
- setsockopt(sock_in, SOL_SOCKET, SO_LINGER, &linger, sizeof(linger));
-
/* Set keepalives if requested. */
if (options.keepalives &&
setsockopt(sock_in, SOL_SOCKET, SO_KEEPALIVE, &on,
* mode; it is just annoying to have the server exit just when you
* are about to discover the bug.
*/
- signal(SIGALRM, grace_alarm_handler);
+ mysignal(SIGALRM, grace_alarm_handler);
if (!debug_flag)
alarm(options.login_grace_time);
sshd_exchange_identification(sock_in, sock_out);
/*
* Check that the connection comes from a privileged port.
- * Rhosts-Authentication only makes sense from priviledged
+ * Rhosts-Authentication only makes sense from privileged
* programs. Of course, if the intruder has root access on his local
* machine, he can connect from any port. So do not use these
* authentication methods from machines that you do not trust.
* the current keystate and exits
*/
if (use_privsep) {
- mm_send_keystate(monitor);
+ mm_send_keystate(pmonitor);
exit(0);
}
verbose("Closing connection to %.100s", remote_ip);
#ifdef USE_PAM
- finish_pam();
+ if (options.use_pam)
+ finish_pam();
#endif /* USE_PAM */
packet_close();
u_char session_key[SSH_SESSION_KEY_LENGTH];
u_char cookie[8];
u_int cipher_type, auth_mask, protocol_flags;
- u_int32_t rand = 0;
+ u_int32_t rnd = 0;
/*
* Generate check bytes that the client must send back in the user
*/
for (i = 0; i < 8; i++) {
if (i % 4 == 0)
- rand = arc4random();
- cookie[i] = rand & 0xff;
- rand >>= 8;
+ rnd = arc4random();
+ cookie[i] = rnd & 0xff;
+ rnd >>= 8;
}
/*
u_char *buf = xmalloc(bytes);
MD5_CTX md;
- log("do_connection: generating a fake encryption key");
+ logit("do_connection: generating a fake encryption key");
BN_bn2bin(session_key_int, buf);
MD5_Init(&md);
MD5_Update(&md, buf, bytes);
debug("Received session key; encryption turned on.");
- /* Send an acknowledgement packet. Note that this packet is sent encrypted. */
+ /* Send an acknowledgment packet. Note that this packet is sent encrypted. */
packet_start(SSH_SMSG_SUCCESS);
packet_send();
packet_write_wait();
myproposal[PROPOSAL_MAC_ALGS_CTOS] =
myproposal[PROPOSAL_MAC_ALGS_STOC] = options.macs;
}
+ if (!options.compression) {
+ myproposal[PROPOSAL_COMP_ALGS_CTOS] =
+ myproposal[PROPOSAL_COMP_ALGS_STOC] = "none";
+ }
myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] = list_hostkey_types();
/* start key exchange */
kex = kex_setup(myproposal);
+ kex->kex[KEX_DH_GRP1_SHA1] = kexdh_server;
+ kex->kex[KEX_DH_GEX_SHA1] = kexgex_server;
kex->server = 1;
kex->client_version_string=client_version_string;
kex->server_version_string=server_version_string;
andersk / openssh.git / blobdiff