*/
#include "includes.h"
-RCSID("$OpenBSD: session.c,v 1.163 2003/08/31 13:29:05 markus Exp $");
+RCSID("$OpenBSD: session.c,v 1.172 2004/01/30 09:48:57 markus Exp $");
#include "ssh.h"
#include "ssh1.h"
#include "session.h"
#include "monitor_wrap.h"
+#if defined(KRB5) && defined(USE_AFS)
+#include <kafs.h>
+#endif
+
#ifdef GSSAPI
#include "ssh-gss.h"
#endif
Session *session_new(void);
void session_set_fds(Session *, int, int, int);
-void session_pty_cleanup(void *);
+void session_pty_cleanup(Session *);
void session_proctitle(Session *);
int session_setup_x11fwd(Session *);
void do_exec_pty(Session *, const char *);
login_cap_t *lc;
#endif
+static int is_child = 0;
+
/* Name and directory of socket for authentication agent forwarding. */
static char *auth_sock_name = NULL;
static char *auth_sock_dir = NULL;
/* removes the agent forwarding socket */
static void
-auth_sock_cleanup_proc(void *_pw)
+auth_sock_cleanup_proc(struct passwd *pw)
{
- struct passwd *pw = _pw;
-
if (auth_sock_name != NULL) {
temporarily_use_uid(pw);
unlink(auth_sock_name);
/* Allocate a buffer for the socket name, and format the name. */
auth_sock_name = xmalloc(MAXPATHLEN);
auth_sock_dir = xmalloc(MAXPATHLEN);
- strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXX", MAXPATHLEN);
+ strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXXXX", MAXPATHLEN);
/* Create private directory for socket */
if (mkdtemp(auth_sock_dir) == NULL) {
snprintf(auth_sock_name, MAXPATHLEN, "%s/agent.%ld",
auth_sock_dir, (long) getpid());
- /* delete agent socket on fatal() */
- fatal_add_cleanup(auth_sock_cleanup_proc, pw);
-
/* Create the socket. */
sock = socket(AF_UNIX, SOCK_STREAM, 0);
if (sock < 0)
restore_uid();
/* Start listening on the socket. */
- if (listen(sock, 5) < 0)
+ if (listen(sock, SSH_LISTEN_BACKLOG) < 0)
packet_disconnect("listen: %.100s", strerror(errno));
/* Allocate a channel for the authentication agent socket. */
return 1;
}
+static void
+display_loginmsg(void)
+{
+ if (buffer_len(&loginmsg) > 0) {
+ buffer_append(&loginmsg, "\0", 1);
+ printf("%s\n", (char *)buffer_ptr(&loginmsg));
+ buffer_clear(&loginmsg);
+ }
+ fflush(stdout);
+}
void
do_authenticated(Authctxt *authctxt)
close(startup_pipe);
startup_pipe = -1;
}
-
/* setup the channel layer */
if (!no_port_forwarding_flag && options.allow_tcp_forwarding)
channel_permit_all_opens();
else
do_authenticated1(authctxt);
- /* remove agent socket */
- if (auth_sock_name != NULL)
- auth_sock_cleanup_proc(authctxt->pw);
#ifdef SESSION_HOOKS
if (options.session_hooks_allow &&
options.session_hooks_shutdown_cmd)
}
}
#endif
-#ifdef KRB5
- if (options.kerberos_ticket_cleanup)
- krb5_cleanup_proc(authctxt);
-#endif
+
+ do_cleanup(authctxt);
}
/*
}
packet_check_eom();
session_close(s);
-#if defined(GSSAPI)
- if (options.gss_cleanup_creds)
- ssh_gssapi_cleanup_creds(NULL);
-#endif
return;
default:
session_proctitle(s);
#if defined(USE_PAM)
- if (options.use_pam) {
+ if (options.use_pam && !use_privsep)
do_pam_setcred(1);
- if (is_pam_password_change_required())
- packet_disconnect("Password change required but no "
- "TTY available");
- }
#endif /* USE_PAM */
/* Fork the child. */
if ((pid = fork()) == 0) {
- fatal_remove_all_cleanups();
+ is_child = 1;
/* Child. Reinitialize the log since the pid has changed. */
log_init(__progname, options.log_level, options.log_facility, log_stderr);
close(inout[0]);
close(err[0]);
+ /*
+ * Clear loginmsg, since it's the child's responsibility to display
+ * it to the user, otherwise multiple sessions may accumulate
+ * multiple copies of the login messages.
+ */
+ buffer_clear(&loginmsg);
+
/*
* Enter the interactive session. Note: server_loop must be able to
* handle the case that fdin and fdout are the same.
#if defined(USE_PAM)
if (options.use_pam) {
do_pam_set_tty(s->tty);
- do_pam_setcred(1);
+ if (!use_privsep)
+ do_pam_setcred(1);
}
#endif
/* Fork the child. */
if ((pid = fork()) == 0) {
- fatal_remove_all_cleanups();
+ is_child = 1;
/* Child. Reinitialize the log because the pid has changed. */
log_init(__progname, options.log_level, options.log_facility, log_stderr);
if (getpeername(packet_get_connection_in(),
(struct sockaddr *) & from, &fromlen) < 0) {
debug("getpeername: %.100s", strerror(errno));
- fatal_cleanup();
+ cleanup_exit(255);
}
}
if (getpeername(packet_get_connection_in(),
(struct sockaddr *) & from, &fromlen) < 0) {
debug("getpeername: %.100s", strerror(errno));
- fatal_cleanup();
+ cleanup_exit(255);
}
}
* If password change is needed, do it now.
* This needs to occur before the ~/.hushlogin check.
*/
- if (options.use_pam && is_pam_password_change_required()) {
- print_pam_messages();
+ if (options.use_pam && !use_privsep && s->authctxt->force_pwchange) {
+ display_loginmsg();
do_pam_chauthtok();
+ s->authctxt->force_pwchange = 0;
/* XXX - signal [net] parent to enable forwardings */
}
#endif
if (check_quietlogin(s, command))
return;
-#ifdef USE_PAM
- if (options.use_pam && !is_pam_password_change_required())
- print_pam_messages();
-#endif /* USE_PAM */
-
- /* display post-login message */
- if (buffer_len(&loginmsg) > 0) {
- buffer_append(&loginmsg, "\0", 1);
- printf("%s\n", (char *)buffer_ptr(&loginmsg));
- }
- buffer_free(&loginmsg);
+ display_loginmsg();
#ifndef NO_SSH_LASTLOG
if (options.print_lastlog && s->last_login_time != 0) {
child_set_env(char ***envp, u_int *envsizep, const char *name,
const char *value)
{
- u_int i, namelen;
char **env;
+ u_int envsize;
+ u_int i, namelen;
/*
* If we're passed an uninitialized list, allocate a single null
xfree(env[i]);
} else {
/* New variable. Expand if necessary. */
- if (i >= (*envsizep) - 1) {
- if (*envsizep >= 1000)
- fatal("child_set_env: too many env vars,"
- " skipping: %.100s", name);
- (*envsizep) += 50;
- env = (*envp) = xrealloc(env, (*envsizep) * sizeof(char *));
+ envsize = *envsizep;
+ if (i >= envsize - 1) {
+ if (envsize >= 1000)
+ fatal("child_set_env: too many env vars");
+ envsize += 50;
+ env = (*envp) = xrealloc(env, envsize * sizeof(char *));
+ *envsizep = envsize;
}
/* Need to set the NULL pointer at end of array beyond the new slot. */
env[i + 1] = NULL;
read_etc_default_login(char ***env, u_int *envsize, uid_t uid)
{
char **tmpenv = NULL, *var;
- u_int i;
- size_t tmpenvsize = 0;
- mode_t mask;
+ u_int i, tmpenvsize = 0;
+ u_long mask;
/*
* We don't want to copy the whole file to the child's environment,
*/
read_environment_file(&tmpenv, &tmpenvsize, "/etc/default/login");
+ if (tmpenv == NULL)
+ return;
+
if (uid == 0)
var = child_get_env(tmpenv, "SUPATH");
else
var = child_get_env(tmpenv, "PATH");
if (var != NULL)
child_set_env(env, envsize, "PATH", var);
-
+
if ((var = child_get_env(tmpenv, "UMASK")) != NULL)
if (sscanf(var, "%5lo", &mask) == 1)
- umask(mask);
-
+ umask((mode_t)mask);
+
for (i = 0; tmpenv[i] != NULL; i++)
xfree(tmpenv[i]);
xfree(tmpenv);
debug3("Copy environment: %s=%s", var_name, var_val);
child_set_env(env, envsize, var_name, var_val);
-
+
xfree(var_name);
}
}
#endif
#ifdef GSSAPI
- /* Allow any GSSAPI methods that we've used to alter
+ /* Allow any GSSAPI methods that we've used to alter
* the childs environment as they see fit
*/
ssh_gssapi_do_child(&env, &envsize);
* needed for loading shared libraries. So the path better
* remains intact here.
*/
- if (getenv("LD_LIBRARY_PATH"))
- child_set_env(&env, &envsize, "LD_LIBRARY_PATH",
- getenv("LD_LIBRARY_PATH"));
# ifdef HAVE_ETC_DEFAULT_LOGIN
read_etc_default_login(&env, &envsize, pw->pw_uid);
path = child_get_env(env, "PATH");
# endif /* HAVE_ETC_DEFAULT_LOGIN */
if (path == NULL || *path == '\0') {
- child_set_env(&env, &envsize, "PATH",
+ child_set_env(&env, &envsize, "PATH",
s->pw->pw_uid == 0 ?
SUPERUSER_PATH : _PATH_STDPATH);
}
if (getenv("TZ"))
child_set_env(&env, &envsize, "TZ", getenv("TZ"));
+#ifdef GSI /* GSI shared libs typically installed in non-system locations. */
+ {
+ char *cp;
+
+ if ((cp = getenv("LD_LIBRARY_PATH")) != NULL)
+ child_set_env(&env, &envsize, "LD_LIBRARY_PATH", cp);
+ if ((cp = getenv("LIBPATH")) != NULL)
+ child_set_env(&env, &envsize, "LIBPATH", cp);
+ if ((cp = getenv("SHLIB_PATH")) != NULL)
+ child_set_env(&env, &envsize, "SHLIB_PATH", cp);
+ if ((cp = getenv("LD_LIBRARYN32_PATH")) != NULL)
+ child_set_env(&env, &envsize, "LD_LIBRARYN32_PATH",cp);
+ if ((cp = getenv("LD_LIBRARY64_PATH")) != NULL)
+ child_set_env(&env, &envsize, "LD_LIBRARY64_PATH",cp);
+ }
+#endif
+
/* Set custom environment options from RSA authentication. */
if (!options.use_login) {
while (custom_environment) {
}
#endif
#ifdef KRB5
- if (s->authctxt->krb5_ticket_file)
+ if (s->authctxt->krb5_ccname)
child_set_env(&env, &envsize, "KRB5CCNAME",
- s->authctxt->krb5_ticket_file);
+ s->authctxt->krb5_ccname);
#endif
#ifdef USE_PAM
/*
* been set by PAM.
*/
if (options.use_pam) {
- char **p = fetch_pam_environment();
+ char **p;
+
+ p = fetch_pam_child_environment();
+ copy_environment(p, &env, &envsize);
+ free_pam_environment(p);
+ p = fetch_pam_environment();
copy_environment(p, &env, &envsize);
free_pam_environment(p);
}
if (debug_flag) {
fprintf(stderr,
"Running %.500s remove %.100s\n",
- options.xauth_location, s->auth_display);
+ options.xauth_location, s->auth_display);
fprintf(stderr,
"%.500s add %.100s %.100s %.100s\n",
options.xauth_location, s->auth_display,
# ifdef __bsdi__
setpgid(0, 0);
# endif
+# ifdef USE_PAM
+ if (options.use_pam) {
+ do_pam_session();
+ do_pam_setcred(0);
+ }
+# endif /* USE_PAM */
if (setusercontext(lc, pw, pw->pw_uid,
(LOGIN_SETALL & ~LOGIN_SETPATH)) < 0) {
perror("unable to set user context");
endgrent();
# ifdef USE_PAM
/*
- * PAM credentials may take the form of supplementary groups.
+ * PAM credentials may take the form of supplementary groups.
* These will have been wiped by the above initgroups() call.
* Reestablish them here.
*/
fatal("Failed to set uids to %u.", (u_int) pw->pw_uid);
}
+static void
+do_pwchange(Session *s)
+{
+ fprintf(stderr, "WARNING: Your password has expired.\n");
+ if (s->ttyfd != -1) {
+ fprintf(stderr,
+ "You must change your password now and login again!\n");
+ execl(_PATH_PASSWD_PROG, "passwd", (char *)NULL);
+ perror("passwd");
+ } else {
+ fprintf(stderr,
+ "Password change required but no TTY available.\n");
+ }
+ exit(1);
+}
+
static void
launch_login(struct passwd *pw, const char *hostname)
{
exit(1);
}
+static void
+child_close_fds(void)
+{
+ int i;
+
+ if (packet_get_connection_in() == packet_get_connection_out())
+ close(packet_get_connection_in());
+ else {
+ close(packet_get_connection_in());
+ close(packet_get_connection_out());
+ }
+ /*
+ * Close all descriptors related to channels. They will still remain
+ * open in the parent.
+ */
+ /* XXX better use close-on-exec? -markus */
+ channel_close_all();
+
+ /*
+ * Close any extra file descriptors. Note that there may still be
+ * descriptors left by system functions. They will be closed later.
+ */
+ endpwent();
+
+ /*
+ * Close any extra open file descriptors so that we don\'t have them
+ * hanging around in clients. Note that we want to do this after
+ * initgroups, because at least on Solaris 2.3 it leaves file
+ * descriptors open.
+ */
+ for (i = 3; i < 64; i++)
+ close(i);
+}
+
/*
* Performs common processing for the child, such as setting up the
* environment, closing extra file descriptors, setting the user and group
char *argv[10];
const char *shell, *shell0, *hostname = NULL;
struct passwd *pw = s->pw;
- u_int i;
#ifdef AFS_KRB5
/* Default place to look for aklog. */
/* remove hostkey from the child's memory */
destroy_sensitive_data();
+ /* Force a password change */
+ if (s->authctxt->force_pwchange) {
+ do_setusercontext(pw);
+ child_close_fds();
+ do_pwchange(s);
+ exit(1);
+ }
+
/* login(1) is only called if we execute the login shell */
if (options.use_login && command != NULL)
options.use_login = 0;
* closed before building the environment, as we call
* get_remote_ipaddr there.
*/
- if (packet_get_connection_in() == packet_get_connection_out())
- close(packet_get_connection_in());
- else {
- close(packet_get_connection_in());
- close(packet_get_connection_out());
- }
- /*
- * Close all descriptors related to channels. They will still remain
- * open in the parent.
- */
- /* XXX better use close-on-exec? -markus */
- channel_close_all();
+ child_close_fds();
/*
- * Close any extra file descriptors. Note that there may still be
- * descriptors left by system functions. They will be closed later.
+ * Must take new environment into use so that .ssh/rc,
+ * /etc/ssh/sshrc and xauth are run in the proper environment.
*/
- endpwent();
+ environ = env;
+#if defined(KRB5) && defined(USE_AFS)
/*
- * Close any extra open file descriptors so that we don\'t have them
- * hanging around in clients. Note that we want to do this after
- * initgroups, because at least on Solaris 2.3 it leaves file
- * descriptors open.
+ * At this point, we check to see if AFS is active and if we have
+ * a valid Kerberos 5 TGT. If so, it seems like a good idea to see
+ * if we can (and need to) extend the ticket into an AFS token. If
+ * we don't do this, we run into potential problems if the user's
+ * home directory is in AFS and it's not world-readable.
*/
- for (i = 3; i < 64; i++)
- close(i);
- /*
- * Must take new environment into use so that .ssh/rc,
- * /etc/ssh/sshrc and xauth are run in the proper environment.
- */
- environ = env;
+ if (options.kerberos_get_afs_token && k_hasafs() &&
+ (s->authctxt->krb5_ctx != NULL)) {
+ char cell[64];
+
+ debug("Getting AFS token");
+
+ k_setpag();
+
+ if (k_afs_cell_of_file(pw->pw_dir, cell, sizeof(cell)) == 0)
+ krb5_afslog(s->authctxt->krb5_ctx,
+ s->authctxt->krb5_fwd_ccache, cell, NULL);
+
+ krb5_afslog_home(s->authctxt->krb5_ctx,
+ s->authctxt->krb5_fwd_ccache, NULL, NULL, pw->pw_dir);
+ }
+#endif
#ifdef AFS_KRB5
}
s->authctxt = authctxt;
s->pw = authctxt->pw;
- if (s->pw == NULL)
+ if (s->pw == NULL || !authctxt->valid)
fatal("no user for session %d", s->self);
debug("session_open: session %d: link with channel %d", s->self, chanid);
s->chanid = chanid;
n_bytes = packet_remaining();
tty_parse_modes(s->ttyfd, &n_bytes);
- /*
- * Add a cleanup function to clear the utmp entry and record logout
- * time in case we call fatal() (e.g., the connection gets closed).
- */
- fatal_add_cleanup(session_pty_cleanup, (void *)s);
if (!use_privsep)
pty_setowner(s->pw, s->tty);
* (e.g., due to a dropped connection).
*/
void
-session_pty_cleanup2(void *session)
+session_pty_cleanup2(Session *s)
{
- Session *s = session;
-
if (s == NULL) {
error("session_pty_cleanup: no session");
return;
}
void
-session_pty_cleanup(void *session)
+session_pty_cleanup(Session *s)
{
- PRIVSEP(session_pty_cleanup2(session));
+ PRIVSEP(session_pty_cleanup2(s));
}
static char *
session_close(Session *s)
{
debug("session_close: session %d pid %ld", s->self, (long)s->pid);
- if (s->ttyfd != -1) {
- fatal_remove_cleanup(session_pty_cleanup, (void *)s);
+ if (s->ttyfd != -1)
session_pty_cleanup(s);
- }
if (s->term)
xfree(s->term);
if (s->display)
* delay detach of session, but release pty, since
* the fd's to the child are already closed
*/
- if (s->ttyfd != -1) {
- fatal_remove_cleanup(session_pty_cleanup, (void *)s);
+ if (s->ttyfd != -1)
session_pty_cleanup(s);
- }
return;
}
/* detach by removing callback */
for (i = 0; i < MAX_SESSIONS; i++) {
Session *s = &sessions[i];
if (s->used && s->ttyfd != -1) {
-
+
if (strncmp(s->tty, "/dev/", 5) != 0) {
cp = strrchr(s->tty, '/');
cp = (cp == NULL) ? s->tty : cp + 1;
} else
cp = s->tty + 5;
-
+
if (buf[0] != '\0')
strlcat(buf, ",", sizeof buf);
strlcat(buf, cp, sizeof buf);
do_authenticated2(Authctxt *authctxt)
{
server_loop2(authctxt);
-#if defined(GSSAPI)
- if (options.gss_cleanup_creds)
- ssh_gssapi_cleanup_creds(NULL);
+}
+
+void
+do_cleanup(Authctxt *authctxt)
+{
+ static int called = 0;
+
+ debug("do_cleanup");
+
+ /* no cleanup if we're in the child for login shell */
+ if (is_child)
+ return;
+
+ /* avoid double cleanup */
+ if (called)
+ return;
+ called = 1;
+
+ if (authctxt == NULL)
+ return;
+#ifdef KRB5
+ if (options.kerberos_ticket_cleanup &&
+ authctxt->krb5_ctx)
+ krb5_cleanup_proc(authctxt);
+#endif
+
+#ifdef GSSAPI
+ if (compat20 && options.gss_cleanup_creds)
+ ssh_gssapi_cleanup_creds();
#endif
+
+#ifdef USE_PAM
+ if (options.use_pam) {
+ sshpam_cleanup();
+ sshpam_thread_cleanup();
+ }
+#endif
+
+ /* remove agent socket */
+ auth_sock_cleanup_proc(authctxt->pw);
+
+ /*
+ * Cleanup ptys/utmp only if privsep is disabled,
+ * or if running in monitor.
+ */
+ if (!use_privsep || mm_is_monitor())
+ session_destroy_all(session_pty_cleanup2);
}