support for password change; ok dtucker@

(set password-dead=1w in login.conf to use this).

4 files changed, 116 insertions, 51 deletions

diff --git a/usr.bin/ssh/auth-passwd.c b/usr.bin/ssh/auth-passwd.c
index 1ef70dee5e6..ac2f1d5b25c 100644
--- a/usr.bin/ssh/auth-passwd.c
+++ b/usr.bin/ssh/auth-passwd.c
@@ -36,15 +36,24 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: auth-passwd.c,v 1.30 2003/11/04 08:54:09 djm Exp $");
+RCSID("$OpenBSD: auth-passwd.c,v 1.31 2004/01/30 09:48:57 markus Exp $");
 
 #include "packet.h"
 #include "log.h"
 #include "servconf.h"
 #include "auth.h"
-
+#include "auth-options.h"
 
 extern ServerOptions options;
+int sys_auth_passwd(Authctxt *, const char *);
+
+static void
+disable_forwarding(void)
+{
+	no_port_forwarding_flag = 1;
+	no_agent_forwarding_flag = 1;
+	no_x11_forwarding_flag = 1;
+}
 
 /*
  * Tries to authenticate the user using password.  Returns true if
@@ -68,26 +77,47 @@ auth_password(Authctxt *authctxt, const char *password)
 		/* Fall back to ordinary passwd authentication. */
 	}
 #endif
+	return (sys_auth_passwd(authctxt, password) && ok);
+}
+
 #ifdef BSD_AUTH
-	if (auth_userokay(pw->pw_name, authctxt->style, "auth-ssh",
-	    (char *)password) == 0)
-		return 0;
-	else
-		return ok;
+int
+sys_auth_passwd(Authctxt *authctxt, const char *password)
+{
+	struct passwd *pw = authctxt->pw;
+	auth_session_t *as;
+
+	as = auth_usercheck(pw->pw_name, authctxt->style, "auth-ssh",
+	    (char *)password);
+	if (auth_getstate(as) & AUTH_PWEXPIRED) {
+		auth_close(as);
+		disable_forwarding();
+		authctxt->force_pwchange = 1;
+		return (1);
+	} else {
+		return (auth_close(as));
+	}
+}
 #else
+int
+sys_auth_passwd(Authctxt *authctxt, const char *password)
+{
+	struct passwd *pw = authctxt->pw;
+	char *encrypted_password;
+
 	/* Check for users with no password. */
 	if (strcmp(password, "") == 0 && strcmp(pw->pw_passwd, "") == 0)
-		return ok;
-	else {
-		/* Encrypt the candidate password using the proper salt. */
-		char *encrypted_password = crypt(password,
-		    (pw->pw_passwd[0] && pw->pw_passwd[1]) ?
-		    pw->pw_passwd : "xx");
-		/*
-		 * Authentication is accepted if the encrypted passwords
-		 * are identical.
-		 */
-		return (strcmp(encrypted_password, pw->pw_passwd) == 0) && ok;
-	}
-#endif
+		return (1);
+
+	/* Encrypt the candidate password using the proper salt. */
+	encrypted_password = crypt(password,
+	    (pw->pw_passwd[0] && pw->pw_passwd[1]) ?
+	    pw->pw_passwd : "xx");
+
+	/*
+	 * Authentication is accepted if the encrypted passwords
+	 * are identical.
+	 */
+	return (strcmp(encrypted_password, pw->pw_passwd) == 0);
 }
+#endif
diff --git a/usr.bin/ssh/auth.h b/usr.bin/ssh/auth.h
index 360e9c3c5d7..e45137bdce8 100644
--- a/usr.bin/ssh/auth.h
+++ b/usr.bin/ssh/auth.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: auth.h,v 1.48 2003/11/04 08:54:09 djm Exp $	*/
+/*	$OpenBSD: auth.h,v 1.49 2004/01/30 09:48:57 markus Exp $	*/
 
 /*
  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
@@ -52,6 +52,7 @@ struct Authctxt {
 	int		 valid;		/* user exists and is allowed to login */
 	int		 attempt;
 	int		 failures;
+	int		 force_pwchange;
 	char		*user;		/* username sent by the client */
 	char		*service;
 	struct passwd	*pw;		/* set if 'valid' */
diff --git a/usr.bin/ssh/pathnames.h b/usr.bin/ssh/pathnames.h
index 3bc6b50e12b..2037054a76d 100644
--- a/usr.bin/ssh/pathnames.h
+++ b/usr.bin/ssh/pathnames.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: pathnames.h,v 1.13 2002/05/23 19:24:30 markus Exp $	*/
+/*	$OpenBSD: pathnames.h,v 1.14 2004/01/30 09:48:57 markus Exp $	*/
 
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
@@ -128,3 +128,6 @@
 
 /* chroot directory for unprivileged user when UsePrivilegeSeparation=yes */
 #define _PATH_PRIVSEP_CHROOT_DIR	"/var/empty"
+
+/* for passwd change */
+#define _PATH_PASSWD_PROG		"/usr/bin/passwd"
diff --git a/usr.bin/ssh/session.c b/usr.bin/ssh/session.c
index fd3cc58a5b4..ab425aed95f 100644
--- a/usr.bin/ssh/session.c
+++ b/usr.bin/ssh/session.c
@@ -33,7 +33,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: session.c,v 1.171 2004/01/13 19:23:15 markus Exp $");
+RCSID("$OpenBSD: session.c,v 1.172 2004/01/30 09:48:57 markus Exp $");
 
 #include "ssh.h"
 #include "ssh1.h"
@@ -1007,6 +1007,22 @@ do_setusercontext(struct passwd *pw)
 }
 
 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)
 {
 	/* Launch login(1). */
@@ -1020,6 +1036,40 @@ 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
@@ -1033,11 +1083,18 @@ do_child(Session *s, const char *command)
 	char *argv[10];
 	const char *shell, *shell0, *hostname = NULL;
 	struct passwd *pw = s->pw;
-	u_int i;
 
 	/* 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;
@@ -1078,33 +1135,7 @@ do_child(Session *s, const char *command)
 	 * 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();
-
-	/*
-	 * 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);
+	child_close_fds();
 
 	/*
 	 * Must take new environment into use so that .ssh/rc,