*/
#include "includes.h"
-RCSID("$OpenBSD: sshd.c,v 1.233 2002/03/19 10:35:39 markus Exp $");
+RCSID("$OpenBSD: sshd.c,v 1.249 2002/06/23 03:30:17 deraadt 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"
int startup_pipe; /* in child */
/* variables used for privilege separation */
-extern struct monitor *monitor;
+extern struct monitor *pmonitor;
extern int use_privsep;
/* Prototypes for various functions defined later in this file. */
static void
main_sigchld_handler(int sig)
{
+ pid_t pid;
int save_errno = errno;
int status;
- while (waitpid(-1, &status, WNOHANG) > 0)
+ while ((pid = waitpid(-1, &status, WNOHANG)) > 0 ||
+ (pid < 0 && errno == EINTR))
;
signal(SIGCHLD, main_sigchld_handler);
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());
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) {
}
}
-
/* Destroy the host and server keys. They will no longer be needed. */
void
destroy_sensitive_data(void)
{
u_int32_t rand[256];
int i;
+ struct passwd *pw;
/* Enable challenge-response authentication for privilege separation */
privsep_challenge_enable();
/* Demote the private keys to public keys. */
demote_sensitive_data();
+ if ((pw = getpwnam(SSH_PRIVSEP_USER)) == NULL)
+ 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*/
if (chroot(_PATH_PRIVSEP_CHROOT_DIR) == -1)
fatal("chroot(\"%s\"): %s", _PATH_PRIVSEP_CHROOT_DIR,
strerror(errno));
if (chdir("/") == -1)
- fatal("chdir(/)");
-
+ fatal("chdir(\"/\"): %s", strerror(errno));
+
/* Drop our privileges */
- setegid(options.unprivileged_group);
- setgid(options.unprivileged_group);
- seteuid(options.unprivileged_user);
- setuid(options.unprivileged_user);
+ debug3("privsep user:group %u:%u", (u_int)pw->pw_uid,
+ (u_int)pw->pw_gid);
+ do_setusercontext(pw);
}
-static void
-privsep_postauth(Authctxt *authctxt, pid_t pid)
+static Authctxt*
+privsep_preauth(void)
{
- extern Authctxt *x_authctxt;
+ Authctxt *authctxt = NULL;
int status;
+ pid_t pid;
+
+ /* Set up unprivileged child process to deal with network data */
+ pmonitor = monitor_init();
+ /* Store a pointer to the kex for later rekeying */
+ 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 %ld", (long)pid);
+
+ close(pmonitor->m_recvfd);
+ authctxt = monitor_child_preauth(pmonitor);
+ close(pmonitor->m_sendfd);
+
+ /* Sync memory */
+ monitor_sync(pmonitor);
- /* Wait for the child's exit status */
- waitpid(pid, &status, 0);
+ /* Wait for the child's exit status */
+ while (waitpid(pid, &status, 0) < 0)
+ if (errno != EINTR)
+ break;
+ return (authctxt);
+ } else {
+ /* child */
+
+ close(pmonitor->m_sendfd);
+
+ /* Demote the child */
+ if (getuid() == 0 || geteuid() == 0)
+ privsep_preauth_child();
+ setproctitle("%s", "[net]");
+ }
+ return (NULL);
+}
+
+static void
+privsep_postauth(Authctxt *authctxt)
+{
+ extern Authctxt *x_authctxt;
/* XXX - Remote port forwarding */
x_authctxt = authctxt;
if (authctxt->pw->pw_uid == 0 || options.use_login) {
/* File descriptor passing is broken or root login */
- monitor_apply_keystate(monitor);
+ monitor_apply_keystate(pmonitor);
use_privsep = 0;
return;
}
-
+
/* Authentication complete */
alarm(0);
if (startup_pipe != -1) {
}
/* 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", pid);
- close(monitor->m_recvfd);
- monitor_child_postauth(monitor);
+ else if (pmonitor->m_pid != 0) {
+ 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 *
list_hostkey_types(void)
{
Key *key;
int ret, key_used = 0;
+#ifdef HAVE_SECUREWARE
+ (void)set_auth_parameters(ac, av);
+#endif
__progname = get_progname(av[0]);
init_rng();
}
}
+ 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);
+ if (st.st_uid != 0 || (st.st_mode & (S_IWGRP|S_IWOTH)) != 0)
+ fatal("Bad owner or mode for %s",
+ _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)
*/
f = fopen(options.pid_file, "wb");
if (f) {
- fprintf(f, "%u\n", (u_int) getpid());
+ fprintf(f, "%ld\n", (long) getpid());
fclose(f);
}
}
if (pid < 0)
error("fork: %.100s", strerror(errno));
else
- debug("Forked child %d.", pid);
+ debug("Forked child %ld.", (long)pid);
close(startup_p[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 0
+ /* XXX: this breaks Solaris */
+ 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
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.
packet_set_nonblocking();
- if (!use_privsep)
- goto skip_privilegeseparation;
-
- /* Set up unprivileged child process to deal with network data */
- monitor = monitor_init();
- /* Store a pointer to the kex for later rekeying */
- monitor->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);
-
- close(monitor->m_recvfd);
- authctxt = monitor_child_preauth(monitor);
- close(monitor->m_sendfd);
-
- /* Sync memory */
- monitor_sync(monitor);
- goto authenticated;
- } else {
- close(monitor->m_sendfd);
-
- /* Demote the child */
- if (getuid() == 0 || geteuid() == 0)
- privsep_preauth_child();
- }
-
- skip_privilegeseparation:
+ if (use_privsep)
+ if ((authctxt = privsep_preauth()) != NULL)
+ goto authenticated;
/* perform the key exchange */
/* authenticate user and start session */
do_ssh1_kex();
authctxt = do_authentication();
}
- if (use_privsep)
- mm_send_keystate(monitor);
-
- /* If we use privilege separation, the unprivileged child exits */
- if (use_privsep)
+ /*
+ * If we use privilege separation, the unprivileged child transfers
+ * the current keystate and exits
+ */
+ if (use_privsep) {
+ mm_send_keystate(pmonitor);
exit(0);
+ }
authenticated:
- /*
+ /*
* In privilege separation, we fork another child and prepare
* file descriptor passing.
*/
if (use_privsep) {
- privsep_postauth(authctxt, pid);
+ privsep_postauth(authctxt);
+ /* the monitor process [priv] will not return */
if (!compat20)
destroy_sensitive_data();
}
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 */
andersk / openssh.git / blobdiff