[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 1.8 2000/08/04 20:30:07 markus 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"

/* 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) {
		int days = time(NULL) / 86400;

		/* Check account expiry */
		if ((spw->sp_expire > 0) && (days > spw->sp_expire))
			return 0;

		/* Check password expiry */
		if ((spw->sp_lstchg > 0) && (spw->sp_inact > 0) && 
			(days > (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"
c345cf9d	8	RCSID("$OpenBSD: auth.c,v 1.8 2000/08/04 20:30:07 markus 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"
e78a59f5	33
7368a6c8	34	/* import */
	35	extern ServerOptions options;
	36	extern char *forced_command;
	37
	38	/*
	39	* Check if the user is allowed to log in via ssh. If user is listed in
	40	* DenyUsers or user's primary group is listed in DenyGroups, false will
	41	* be returned. If AllowUsers isn't empty and user isn't listed there, or
	42	* if AllowGroups isn't empty and user isn't listed there, false will be
6ae2364d	43	* returned.
7368a6c8	44	* If the user's shell is not executable, false will be returned.
6ae2364d	45	* Otherwise true is returned.
7368a6c8	46	*/
a306f2dd	47	int
7368a6c8	48	allowed_user(struct passwd * pw)
	49	{
	50	struct stat st;
	51	struct group *grp;
301e9b01	52	char *shell;
7368a6c8	53	int i;
	54	#ifdef WITH_AIXAUTHENTICATE
	55	char *loginmsg;
	56	#endif /* WITH_AIXAUTHENTICATE */
4cb5ffa0	57	#if defined(HAVE_SHADOW_H) && !defined(DISABLE_SHADOW) && \
	58	defined(HAS_SHADOW_EXPIRE)
	59	struct spwd *spw;
7368a6c8	60
	61	/* Shouldn't be called if pw is NULL, but better safe than sorry... */
	62	if (!pw)
	63	return 0;
	64
4cb5ffa0	65	spw = getspnam(pw->pw_name);
27494968	66	if (spw != NULL) {
27494968	67	int days = time(NULL) / 86400;
4cb5ffa0	68
27494968	69	/* Check account expiry */
	70	if ((spw->sp_expire > 0) && (days > spw->sp_expire))
	71	return 0;
	72
	73	/* Check password expiry */
	74	if ((spw->sp_lstchg > 0) && (spw->sp_inact > 0) &&
	75	(days > (spw->sp_lstchg + spw->sp_inact)))
	76	return 0;
	77	}
4cb5ffa0	78	#else
	79	/* Shouldn't be called if pw is NULL, but better safe than sorry... */
	80	if (!pw)
	81	return 0;
	82	#endif
	83
301e9b01	84	/*
	85	* Get the shell from the password data. An empty shell field is
	86	* legal, and means /bin/sh.
	87	*/
	88	shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell;
	89
	90	/* deny if shell does not exists or is not executable */
	91	if (stat(shell, &st) != 0)
7368a6c8	92	return 0;
	93	if (!((st.st_mode & S_IFREG) && (st.st_mode & (S_IXOTH\|S_IXUSR\|S_IXGRP))))
	94	return 0;
	95
	96	/* Return false if user is listed in DenyUsers */
	97	if (options.num_deny_users > 0) {
	98	if (!pw->pw_name)
	99	return 0;
	100	for (i = 0; i < options.num_deny_users; i++)
	101	if (match_pattern(pw->pw_name, options.deny_users[i]))
	102	return 0;
	103	}
	104	/* Return false if AllowUsers isn't empty and user isn't listed there */
	105	if (options.num_allow_users > 0) {
	106	if (!pw->pw_name)
	107	return 0;
	108	for (i = 0; i < options.num_allow_users; i++)
	109	if (match_pattern(pw->pw_name, options.allow_users[i]))
	110	break;
	111	/* i < options.num_allow_users iff we break for loop */
	112	if (i >= options.num_allow_users)
	113	return 0;
	114	}
	115	/* Get the primary group name if we need it. Return false if it fails */
	116	if (options.num_deny_groups > 0 \|\| options.num_allow_groups > 0) {
	117	grp = getgrgid(pw->pw_gid);
	118	if (!grp)
	119	return 0;
	120
	121	/* Return false if user's group is listed in DenyGroups */
	122	if (options.num_deny_groups > 0) {
	123	if (!grp->gr_name)
	124	return 0;
	125	for (i = 0; i < options.num_deny_groups; i++)
	126	if (match_pattern(grp->gr_name, options.deny_groups[i]))
	127	return 0;
	128	}
	129	/*
	130	* Return false if AllowGroups isn't empty and user's group
	131	* isn't listed there
	132	*/
	133	if (options.num_allow_groups > 0) {
	134	if (!grp->gr_name)
	135	return 0;
	136	for (i = 0; i < options.num_allow_groups; i++)
	137	if (match_pattern(grp->gr_name, options.allow_groups[i]))
	138	break;
	139	/* i < options.num_allow_groups iff we break for
	140	loop */
	141	if (i >= options.num_allow_groups)
	142	return 0;
	143	}
	144	}
	145
	146	#ifdef WITH_AIXAUTHENTICATE
5daf7064	147	if (loginrestrictions(pw->pw_name, S_RLOGIN, NULL, &loginmsg) != 0) {
c1ef8333	148	if (loginmsg && *loginmsg) {
	149	/* Remove embedded newlines (if any) */
	150	char *p;
5daf7064	151	for (p = loginmsg; *p; p++) {
c1ef8333	152	if (*p == '\n')
c1ef8333	153	*p = ' ';
5daf7064	154	}
c1ef8333	155	/* Remove trailing newline */
c1ef8333	156	*--p = '\0';
5daf7064	157	log("Login restricted for %s: %.100s", pw->pw_name, loginmsg);
c1ef8333	158	}
7368a6c8	159	return 0;
c1ef8333	160	}
7368a6c8	161	#endif /* WITH_AIXAUTHENTICATE */
	162
	163	/* We found no reason not to let this user try to log on... */
	164	return 1;
	165	}