[openssh.git] / auth.c

/*
 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
 *                    All rights reserved
 * Copyright (c) 2000 Markus Friedl. All rights reserved.
 */

#include "includes.h"
RCSID("$OpenBSD: auth.c,v 1.7 2000/05/17 21:37:24 deraadt Exp $");

#include "xmalloc.h"
#include "rsa.h"
#include "ssh.h"
#include "pty.h"
#include "packet.h"
#include "buffer.h"
#include "cipher.h"
#include "mpaux.h"
#include "servconf.h"
#include "compat.h"
#include "channels.h"
#include "match.h"
#ifdef HAVE_LOGIN_H
#include <login.h>
#endif
#if defined(HAVE_SHADOW_H) && !defined(DISABLE_SHADOW)
#include <shadow.h>
#endif /* defined(HAVE_SHADOW_H) && !defined(DISABLE_SHADOW) */

#include "bufaux.h"
#include "ssh2.h"
#include "auth.h"
#include "session.h"
#include "dispatch.h"


/* import */
extern ServerOptions options;
extern char *forced_command;

/*
 * Check if the user is allowed to log in via ssh. If user is listed in
 * DenyUsers or user's primary group is listed in DenyGroups, false will
 * be returned. If AllowUsers isn't empty and user isn't listed there, or
 * if AllowGroups isn't empty and user isn't listed there, false will be
 * returned.
 * If the user's shell is not executable, false will be returned.
 * Otherwise true is returned.
 */
int
allowed_user(struct passwd * pw)
{
	struct stat st;
	struct group *grp;
	char *shell;
	int i;
#ifdef WITH_AIXAUTHENTICATE
	char *loginmsg;
#endif /* WITH_AIXAUTHENTICATE */
#if defined(HAVE_SHADOW_H) && !defined(DISABLE_SHADOW) && \
	defined(HAS_SHADOW_EXPIRE)
  struct spwd *spw;

	/* Shouldn't be called if pw is NULL, but better safe than sorry... */
	if (!pw)
		return 0;

	spw = getspnam(pw->pw_name);
	if (spw == NULL)
		return 0;
	
	/* Check account expiry */
	if ((spw->sp_expire > 0) && ((time(NULL) / 86400) > spw->sp_expire))
		return 0;

	/* Check password expiry */
	if ((spw->sp_lstchg > 0) && (spw->sp_inact > 0) && 
		((time(NULL) / 86400) > (spw->sp_lstchg + spw->sp_inact)))
		return 0;
#else
	/* Shouldn't be called if pw is NULL, but better safe than sorry... */
	if (!pw)
		return 0;
#endif

	/*
	 * Get the shell from the password data.  An empty shell field is
	 * legal, and means /bin/sh.
	 */
	shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell;

	/* deny if shell does not exists or is not executable */
	if (stat(shell, &st) != 0)
		return 0;
	if (!((st.st_mode & S_IFREG) && (st.st_mode & (S_IXOTH|S_IXUSR|S_IXGRP))))
		return 0;

	/* Return false if user is listed in DenyUsers */
	if (options.num_deny_users > 0) {
		if (!pw->pw_name)
			return 0;
		for (i = 0; i < options.num_deny_users; i++)
			if (match_pattern(pw->pw_name, options.deny_users[i]))
				return 0;
	}
	/* Return false if AllowUsers isn't empty and user isn't listed there */
	if (options.num_allow_users > 0) {
		if (!pw->pw_name)
			return 0;
		for (i = 0; i < options.num_allow_users; i++)
			if (match_pattern(pw->pw_name, options.allow_users[i]))
				break;
		/* i < options.num_allow_users iff we break for loop */
		if (i >= options.num_allow_users)
			return 0;
	}
	/* Get the primary group name if we need it. Return false if it fails */
	if (options.num_deny_groups > 0 || options.num_allow_groups > 0) {
		grp = getgrgid(pw->pw_gid);
		if (!grp)
			return 0;

		/* Return false if user's group is listed in DenyGroups */
		if (options.num_deny_groups > 0) {
			if (!grp->gr_name)
				return 0;
			for (i = 0; i < options.num_deny_groups; i++)
				if (match_pattern(grp->gr_name, options.deny_groups[i]))
					return 0;
		}
		/*
		 * Return false if AllowGroups isn't empty and user's group
		 * isn't listed there
		 */
		if (options.num_allow_groups > 0) {
			if (!grp->gr_name)
				return 0;
			for (i = 0; i < options.num_allow_groups; i++)
				if (match_pattern(grp->gr_name, options.allow_groups[i]))
					break;
			/* i < options.num_allow_groups iff we break for
			   loop */
			if (i >= options.num_allow_groups)
				return 0;
		}
	}

#ifdef WITH_AIXAUTHENTICATE
	if (loginrestrictions(pw->pw_name, S_RLOGIN, NULL, &loginmsg) != 0) {
		if (loginmsg && *loginmsg) {
			/* Remove embedded newlines (if any) */
			char *p;
			for (p = loginmsg; *p; p++) {
				if (*p == '\n')
					*p = ' ';
			}
			/* Remove trailing newline */
			*--p = '\0';
			log("Login restricted for %s: %.100s", pw->pw_name, loginmsg);
		}
		return 0;
	}
#endif /* WITH_AIXAUTHENTICATE */

	/* We found no reason not to let this user try to log on... */
	return 1;
}
Commit	Line	Data
7368a6c8	1	/*
	2	* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
	3	* All rights reserved
e78a59f5	4	* Copyright (c) 2000 Markus Friedl. All rights reserved.
7368a6c8	5	*/
	6
	7	#include "includes.h"
301e9b01	8	RCSID("$OpenBSD: auth.c,v 1.7 2000/05/17 21:37:24 deraadt Exp $");
7368a6c8	9
	10	#include "xmalloc.h"
	11	#include "rsa.h"
	12	#include "ssh.h"
	13	#include "pty.h"
	14	#include "packet.h"
	15	#include "buffer.h"
	16	#include "cipher.h"
	17	#include "mpaux.h"
	18	#include "servconf.h"
e78a59f5	19	#include "compat.h"
7368a6c8	20	#include "channels.h"
7368a6c8	21	#include "match.h"
c1ef8333	22	#ifdef HAVE_LOGIN_H
	23	#include <login.h>
	24	#endif
4cb5ffa0	25	#if defined(HAVE_SHADOW_H) && !defined(DISABLE_SHADOW)
	26	#include <shadow.h>
	27	#endif /* defined(HAVE_SHADOW_H) && !defined(DISABLE_SHADOW) */
7368a6c8	28
e78a59f5	29	#include "bufaux.h"
	30	#include "ssh2.h"
	31	#include "auth.h"
7368a6c8	32	#include "session.h"
	33	#include "dispatch.h"
	34
e78a59f5	35
7368a6c8	36	/* import */
	37	extern ServerOptions options;
	38	extern char *forced_command;
	39
	40	/*
	41	* Check if the user is allowed to log in via ssh. If user is listed in
	42	* DenyUsers or user's primary group is listed in DenyGroups, false will
	43	* be returned. If AllowUsers isn't empty and user isn't listed there, or
	44	* if AllowGroups isn't empty and user isn't listed there, false will be
6ae2364d	45	* returned.
7368a6c8	46	* If the user's shell is not executable, false will be returned.
6ae2364d	47	* Otherwise true is returned.
7368a6c8	48	*/
a306f2dd	49	int
7368a6c8	50	allowed_user(struct passwd * pw)
	51	{
	52	struct stat st;
	53	struct group *grp;
301e9b01	54	char *shell;
7368a6c8	55	int i;
	56	#ifdef WITH_AIXAUTHENTICATE
	57	char *loginmsg;
	58	#endif /* WITH_AIXAUTHENTICATE */
4cb5ffa0	59	#if defined(HAVE_SHADOW_H) && !defined(DISABLE_SHADOW) && \
	60	defined(HAS_SHADOW_EXPIRE)
	61	struct spwd *spw;
7368a6c8	62
	63	/* Shouldn't be called if pw is NULL, but better safe than sorry... */
	64	if (!pw)
	65	return 0;
	66
4cb5ffa0	67	spw = getspnam(pw->pw_name);
	68	if (spw == NULL)
	69	return 0;
	70
	71	/* Check account expiry */
	72	if ((spw->sp_expire > 0) && ((time(NULL) / 86400) > spw->sp_expire))
	73	return 0;
	74
	75	/* Check password expiry */
	76	if ((spw->sp_lstchg > 0) && (spw->sp_inact > 0) &&
	77	((time(NULL) / 86400) > (spw->sp_lstchg + spw->sp_inact)))
	78	return 0;
	79	#else
	80	/* Shouldn't be called if pw is NULL, but better safe than sorry... */
	81	if (!pw)
	82	return 0;
	83	#endif
	84
301e9b01	85	/*
	86	* Get the shell from the password data. An empty shell field is
	87	* legal, and means /bin/sh.
	88	*/
	89	shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell;
	90
	91	/* deny if shell does not exists or is not executable */
	92	if (stat(shell, &st) != 0)
7368a6c8	93	return 0;
	94	if (!((st.st_mode & S_IFREG) && (st.st_mode & (S_IXOTH\|S_IXUSR\|S_IXGRP))))
	95	return 0;
	96
	97	/* Return false if user is listed in DenyUsers */
	98	if (options.num_deny_users > 0) {
	99	if (!pw->pw_name)
	100	return 0;
	101	for (i = 0; i < options.num_deny_users; i++)
	102	if (match_pattern(pw->pw_name, options.deny_users[i]))
	103	return 0;
	104	}
	105	/* Return false if AllowUsers isn't empty and user isn't listed there */
	106	if (options.num_allow_users > 0) {
	107	if (!pw->pw_name)
	108	return 0;
	109	for (i = 0; i < options.num_allow_users; i++)
	110	if (match_pattern(pw->pw_name, options.allow_users[i]))
	111	break;
	112	/* i < options.num_allow_users iff we break for loop */
	113	if (i >= options.num_allow_users)
	114	return 0;
	115	}
	116	/* Get the primary group name if we need it. Return false if it fails */
	117	if (options.num_deny_groups > 0 \|\| options.num_allow_groups > 0) {
	118	grp = getgrgid(pw->pw_gid);
	119	if (!grp)
	120	return 0;
	121
	122	/* Return false if user's group is listed in DenyGroups */
	123	if (options.num_deny_groups > 0) {
	124	if (!grp->gr_name)
	125	return 0;
	126	for (i = 0; i < options.num_deny_groups; i++)
	127	if (match_pattern(grp->gr_name, options.deny_groups[i]))
	128	return 0;
	129	}
	130	/*
	131	* Return false if AllowGroups isn't empty and user's group
	132	* isn't listed there
	133	*/
	134	if (options.num_allow_groups > 0) {
	135	if (!grp->gr_name)
	136	return 0;
	137	for (i = 0; i < options.num_allow_groups; i++)
	138	if (match_pattern(grp->gr_name, options.allow_groups[i]))
	139	break;
	140	/* i < options.num_allow_groups iff we break for
	141	loop */
	142	if (i >= options.num_allow_groups)
	143	return 0;
	144	}
	145	}
	146
	147	#ifdef WITH_AIXAUTHENTICATE
5daf7064	148	if (loginrestrictions(pw->pw_name, S_RLOGIN, NULL, &loginmsg) != 0) {
c1ef8333	149	if (loginmsg && *loginmsg) {
	150	/* Remove embedded newlines (if any) */
	151	char *p;
5daf7064	152	for (p = loginmsg; *p; p++) {
c1ef8333	153	if (*p == '\n')
c1ef8333	154	*p = ' ';
5daf7064	155	}
c1ef8333	156	/* Remove trailing newline */
c1ef8333	157	*--p = '\0';
5daf7064	158	log("Login restricted for %s: %.100s", pw->pw_name, loginmsg);
c1ef8333	159	}
7368a6c8	160	return 0;
c1ef8333	161	}
7368a6c8	162	#endif /* WITH_AIXAUTHENTICATE */
	163
	164	/* We found no reason not to let this user try to log on... */
	165	return 1;
	166	}