[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

#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 */

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

	/*
	 * 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
7368a6c8	25
e78a59f5	26	#include "bufaux.h"
	27	#include "ssh2.h"
	28	#include "auth.h"
7368a6c8	29	#include "session.h"
	30	#include "dispatch.h"
	31
e78a59f5	32
7368a6c8	33	/* import */
	34	extern ServerOptions options;
	35	extern char *forced_command;
	36
	37	/*
	38	* Check if the user is allowed to log in via ssh. If user is listed in
	39	* DenyUsers or user's primary group is listed in DenyGroups, false will
	40	* be returned. If AllowUsers isn't empty and user isn't listed there, or
	41	* if AllowGroups isn't empty and user isn't listed there, false will be
6ae2364d	42	* returned.
7368a6c8	43	* If the user's shell is not executable, false will be returned.
6ae2364d	44	* Otherwise true is returned.
7368a6c8	45	*/
a306f2dd	46	int
7368a6c8	47	allowed_user(struct passwd * pw)
	48	{
	49	struct stat st;
	50	struct group *grp;
301e9b01	51	char *shell;
7368a6c8	52	int i;
	53	#ifdef WITH_AIXAUTHENTICATE
	54	char *loginmsg;
	55	#endif /* WITH_AIXAUTHENTICATE */
	56
	57	/* Shouldn't be called if pw is NULL, but better safe than sorry... */
	58	if (!pw)
	59	return 0;
	60
301e9b01	61	/*
	62	* Get the shell from the password data. An empty shell field is
	63	* legal, and means /bin/sh.
	64	*/
	65	shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell;
	66
	67	/* deny if shell does not exists or is not executable */
	68	if (stat(shell, &st) != 0)
7368a6c8	69	return 0;
	70	if (!((st.st_mode & S_IFREG) && (st.st_mode & (S_IXOTH\|S_IXUSR\|S_IXGRP))))
	71	return 0;
	72
	73	/* Return false if user is listed in DenyUsers */
	74	if (options.num_deny_users > 0) {
	75	if (!pw->pw_name)
	76	return 0;
	77	for (i = 0; i < options.num_deny_users; i++)
	78	if (match_pattern(pw->pw_name, options.deny_users[i]))
	79	return 0;
	80	}
	81	/* Return false if AllowUsers isn't empty and user isn't listed there */
	82	if (options.num_allow_users > 0) {
	83	if (!pw->pw_name)
	84	return 0;
	85	for (i = 0; i < options.num_allow_users; i++)
	86	if (match_pattern(pw->pw_name, options.allow_users[i]))
	87	break;
	88	/* i < options.num_allow_users iff we break for loop */
	89	if (i >= options.num_allow_users)
	90	return 0;
	91	}
	92	/* Get the primary group name if we need it. Return false if it fails */
	93	if (options.num_deny_groups > 0 \|\| options.num_allow_groups > 0) {
	94	grp = getgrgid(pw->pw_gid);
	95	if (!grp)
	96	return 0;
	97
	98	/* Return false if user's group is listed in DenyGroups */
	99	if (options.num_deny_groups > 0) {
	100	if (!grp->gr_name)
	101	return 0;
	102	for (i = 0; i < options.num_deny_groups; i++)
	103	if (match_pattern(grp->gr_name, options.deny_groups[i]))
	104	return 0;
	105	}
	106	/*
	107	* Return false if AllowGroups isn't empty and user's group
	108	* isn't listed there
	109	*/
	110	if (options.num_allow_groups > 0) {
	111	if (!grp->gr_name)
	112	return 0;
	113	for (i = 0; i < options.num_allow_groups; i++)
	114	if (match_pattern(grp->gr_name, options.allow_groups[i]))
	115	break;
	116	/* i < options.num_allow_groups iff we break for
	117	loop */
	118	if (i >= options.num_allow_groups)
	119	return 0;
	120	}
	121	}
	122
	123	#ifdef WITH_AIXAUTHENTICATE
c1ef8333	124	if (loginrestrictions(pw->pw_name,S_RLOGIN,NULL,&loginmsg) != 0) {
	125	if (loginmsg && *loginmsg) {
	126	/* Remove embedded newlines (if any) */
	127	char *p;
	128	for (p = loginmsg; *p; p++)
	129	if (*p == '\n')
	130	*p = ' ';
	131	/* Remove trailing newline */
	132	*--p = '\0';
	133	log("Login restricted for %s: %.100s",
	134	pw->pw_name, loginmsg);
	135	}
7368a6c8	136	return 0;
c1ef8333	137	}
7368a6c8	138	#endif /* WITH_AIXAUTHENTICATE */
	139
	140	/* We found no reason not to let this user try to log on... */
	141	return 1;
	142	}