[nss_nonlocal.git] / nonlocal-group.c

/*
 * nonlocal-group.c
 * group database for nss_nonlocal proxy
 *
 * Copyright © 2007–2010 Anders Kaseorg <andersk@mit.edu> and Tim
 * Abbott <tabbott@mit.edu>
 *
 * This file is part of nss_nonlocal.
 *
 * nss_nonlocal is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public License
 * as published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * nss_nonlocal is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with nss_nonlocal; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301  USA
 */

#define _GNU_SOURCE
#include <sys/types.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <dlfcn.h>
#include <stdio.h>
#include <syslog.h>
#include <errno.h>
#include <pwd.h>
#include <grp.h>
#include <nss.h>
#include "nsswitch-internal.h"
#include "nonlocal.h"

/*
 * If the MAGIC_NONLOCAL_GROUPNAME local group exists, then nonlocal
 * users will be automatically added to it.  Furthermore, if a local
 * user is added to this group, then that user will inherit any
 * nonlocal gids from a nonlocal user of the same name, as
 * supplementary gids.
 */
#define MAGIC_NONLOCAL_GROUPNAME "nss-nonlocal-users"

/*
 * If the MAGIC_LOCAL_GROUPNAME local group exists, then local users
 * will be automatically added to it.
 */
#define MAGIC_LOCAL_GROUPNAME "nss-local-users"


enum nss_status
_nss_nonlocal_getgrnam_r(const char *name, struct group *grp,
			 char *buffer, size_t buflen, int *errnop);

enum nss_status
_nss_nonlocal_getgrgid_r(gid_t gid, struct group *grp,
			 char *buffer, size_t buflen, int *errnop);


static service_user *__nss_group_nonlocal_database;

static int
internal_function
__nss_group_nonlocal_lookup(service_user **ni, const char *fct_name,
			    void **fctp)
{
    if (__nss_group_nonlocal_database == NULL
	&& __nss_database_lookup("group_nonlocal", NULL, NULL,
				 &__nss_group_nonlocal_database) < 0)
	return -1;

    *ni = __nss_group_nonlocal_database;

    *fctp = __nss_lookup_function(*ni, fct_name);
    return 0;
}


enum nss_status
check_nonlocal_gid(const char *user, gid_t gid, int *errnop)
{
    enum nss_status status;
    struct group gbuf;
    char *buf;
    size_t buflen = sysconf(_SC_GETGR_R_SIZE_MAX);
    const struct walk_nss w = {
	.lookup = &__nss_group_lookup, .fct_name = "getgrgid_r",
	.status = &status, .errnop = errnop, .buf = &buf, .buflen = &buflen
    };
    const __typeof__(&_nss_nonlocal_getgrgid_r) self = &_nss_nonlocal_getgrgid_r;
#define args (gid, &gbuf, buf, buflen, errnop)
#include "walk_nss.h"
#undef args

    if (status == NSS_STATUS_SUCCESS) {
	syslog(LOG_DEBUG, "nss_nonlocal: removing local group %u (%s) from non-local user %s\n", gbuf.gr_gid, gbuf.gr_name, user);
	free(buf);
	status = NSS_STATUS_NOTFOUND;
    } else if (status != NSS_STATUS_TRYAGAIN) {
	status = NSS_STATUS_SUCCESS;
    }

    return status;
}

enum nss_status
check_nonlocal_group(const char *user, struct group *grp, int *errnop)
{
    enum nss_status status = NSS_STATUS_SUCCESS;
    int old_errno = errno;
    char *end;
    unsigned long gid;

    errno = 0;
    gid = strtoul(grp->gr_name, &end, 10);
    if (errno == 0 && *end == '\0' && (gid_t)gid == gid) {
	errno = old_errno;
	status = check_nonlocal_gid(user, gid, errnop);
    } else
	errno = old_errno;
    if (status != NSS_STATUS_SUCCESS)
	return status;

    return check_nonlocal_gid(user, grp->gr_gid, errnop);
}

enum nss_status
get_local_group(const char *name, struct group *grp, char **buffer, int *errnop)
{
    enum nss_status status;
    size_t buflen = sysconf(_SC_GETGR_R_SIZE_MAX);
    const struct walk_nss w = {
	.lookup = &__nss_group_lookup, .fct_name = "getgrnam_r",
	.status = &status, .errnop = errnop, .buf = buffer, .buflen = &buflen
    };
    const __typeof__(&_nss_nonlocal_getgrnam_r) self = &_nss_nonlocal_getgrnam_r;
#define args (name, grp, *buffer, buflen, errnop)
#include "walk_nss.h"
#undef args
    return status;
}

static service_user *grent_startp, *grent_nip;
static void *grent_fct_start;
static union {
    enum nss_status (*l)(struct group *grp, char *buffer, size_t buflen,
			 int *errnop);
    void *ptr;
} grent_fct;
static const char *grent_fct_name = "getgrent_r";

enum nss_status
_nss_nonlocal_setgrent(int stayopen)
{
    enum nss_status status;
    const struct walk_nss w = {
	.lookup = &__nss_group_nonlocal_lookup, .fct_name = "setgrent",
	.status = &status
    };
    const __typeof__(&_nss_nonlocal_setgrent) self = NULL;
#define args (stayopen)
#include "walk_nss.h"
#undef args
    if (status != NSS_STATUS_SUCCESS)
	return status;

    if (grent_fct_start == NULL)
	__nss_group_nonlocal_lookup(&grent_startp, grent_fct_name,
				    &grent_fct_start);
    grent_nip = grent_startp;
    grent_fct.ptr = grent_fct_start;
    return NSS_STATUS_SUCCESS;
}

enum nss_status
_nss_nonlocal_endgrent(void)
{
    enum nss_status status;
    const struct walk_nss w = {
	.lookup = &__nss_group_nonlocal_lookup, .fct_name = "endgrent",
	.status = &status
    };
    const __typeof__(&_nss_nonlocal_endgrent) self = NULL;

    grent_nip = NULL;

#define args ()
#include "walk_nss.h"
#undef args
    return status;
}

enum nss_status
_nss_nonlocal_getgrent_r(struct group *grp, char *buffer, size_t buflen,
			 int *errnop)
{
    enum nss_status status;

    char *nonlocal_ignore = getenv(NONLOCAL_IGNORE_ENV);
    if (nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0')
	return NSS_STATUS_UNAVAIL;

    if (grent_nip == NULL) {
	status = _nss_nonlocal_setgrent(0);
	if (status != NSS_STATUS_SUCCESS)
	    return status;
    }
    do {
	if (grent_fct.ptr == NULL)
	    status = NSS_STATUS_UNAVAIL;
	else {
	    int nonlocal_errno;
	    do
		status = DL_CALL_FCT(grent_fct.l, (grp, buffer, buflen, errnop));
	    while (status == NSS_STATUS_SUCCESS &&
		   check_nonlocal_group("(unknown)", grp, &nonlocal_errno) != NSS_STATUS_SUCCESS);
	}
	if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE)
	    return status;

	if (status == NSS_STATUS_SUCCESS)
	    return NSS_STATUS_SUCCESS;
    } while (__nss_next(&grent_nip, grent_fct_name, &grent_fct.ptr, status, 0) == 0);

    grent_nip = NULL;
    return NSS_STATUS_NOTFOUND;
}


enum nss_status
_nss_nonlocal_getgrnam_r(const char *name, struct group *grp,
			 char *buffer, size_t buflen, int *errnop)
{
    enum nss_status status;
    const struct walk_nss w = {
	.lookup = &__nss_group_nonlocal_lookup, .fct_name = "getgrnam_r",
	.status = &status, .errnop = errnop
    };
    const __typeof__(&_nss_nonlocal_getgrnam_r) self = NULL;

    char *nonlocal_ignore = getenv(NONLOCAL_IGNORE_ENV);
    if (nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0')
	return NSS_STATUS_UNAVAIL;

#define args (name, grp, buffer, buflen, errnop)
#include "walk_nss.h"
#undef args
    if (status != NSS_STATUS_SUCCESS)
	return status;

    if (strcmp(name, grp->gr_name) != 0) {
	syslog(LOG_ERR, "nss_nonlocal: discarding group %s from lookup for group %s\n", grp->gr_name, name);
	return NSS_STATUS_NOTFOUND;
    }

    return check_nonlocal_group(name, grp, errnop);
}

enum nss_status
_nss_nonlocal_getgrgid_r(gid_t gid, struct group *grp,
			 char *buffer, size_t buflen, int *errnop)
{
    enum nss_status status;
    const struct walk_nss w = {
	.lookup = &__nss_group_nonlocal_lookup, .fct_name = "getgrgid_r",
	.status = &status, .errnop = errnop
    };
    const __typeof__(&_nss_nonlocal_getgrgid_r) self = NULL;

    char *nonlocal_ignore = getenv(NONLOCAL_IGNORE_ENV);
    if (nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0')
	return NSS_STATUS_UNAVAIL;

#define args (gid, grp, buffer, buflen, errnop)
#include "walk_nss.h"
#undef args
    if (status != NSS_STATUS_SUCCESS)
	return status;

    if (gid != grp->gr_gid) {
	syslog(LOG_ERR, "nss_nonlocal: discarding gid %d from lookup for gid %d\n", grp->gr_gid, gid);
	return NSS_STATUS_NOTFOUND;
    }

    return check_nonlocal_group(grp->gr_name, grp, errnop);
}

static bool
add_group(gid_t group, long int *start, long int *size, gid_t **groupsp,
	  long int limit, int *errnop, enum nss_status *status)
{
    int i, old_errno = errno;
    for (i = 0; i < *start; ++i)
	if ((*groupsp)[i] == group)
	    return true;
    if (*start + 1 > *size) {
	gid_t *newgroups;
	long int newsize = 2 * *size;
	if (limit > 0) {
	    if (*size >= limit) {
		*status = NSS_STATUS_SUCCESS;
		return false;
	    }
	    if (newsize > limit)
		newsize = limit;
	}
	newgroups = realloc(*groupsp, newsize * sizeof((*groupsp)[0]));
	errno = old_errno;
	if (newgroups == NULL) {
	    *errnop = ENOMEM;
	    *status = NSS_STATUS_TRYAGAIN;
	    return false;
	}
	*groupsp = newgroups;
	*size = newsize;
    }
    (*groupsp)[(*start)++] = group;
    return true;
}

enum nss_status
_nss_nonlocal_initgroups_dyn(const char *user, gid_t group, long int *start,
			     long int *size, gid_t **groupsp, long int limit,
			     int *errnop)
{
    enum nss_status status;
    const struct walk_nss w = {
	.lookup = &__nss_group_nonlocal_lookup, .fct_name = "initgroups_dyn",
	.status = &status, .errnop = errnop
    };
    const __typeof__(&_nss_nonlocal_initgroups_dyn) self = NULL;

    struct group local_users_group, nonlocal_users_group;
    bool is_nonlocal = true;
    char *buffer;
    int in, out, i;

    /* Check that the user is a nonlocal user, or a member of the
     * MAGIC_NONLOCAL_GROUPNAME group, before adding any groups. */
    status = check_nonlocal_user(user, errnop);
    if (status == NSS_STATUS_TRYAGAIN) {
	return status;
    } else if (status != NSS_STATUS_SUCCESS) {
	is_nonlocal = false;

	status = get_local_group(MAGIC_LOCAL_GROUPNAME,
				 &local_users_group, &buffer, errnop);
	if (status == NSS_STATUS_SUCCESS) {
	    free(buffer);
	    if (!add_group(local_users_group.gr_gid, start, size, groupsp,
			   limit, errnop, &status))
		return status;
	} else if (status == NSS_STATUS_TRYAGAIN) {
	    return status;
	} else {
	    syslog(LOG_WARNING,
		   "nss_nonlocal: Group %s does not exist locally!",
		   MAGIC_LOCAL_GROUPNAME);
	}
    }

    status = get_local_group(MAGIC_NONLOCAL_GROUPNAME,
			     &nonlocal_users_group, &buffer, errnop);
    if (status == NSS_STATUS_SUCCESS) {
	free(buffer);
	if (is_nonlocal) {
	    if (!add_group(nonlocal_users_group.gr_gid, start, size, groupsp,
			   limit, errnop, &status))
		return status;
	} else {
	    int i;
	    for (i = 0; i < *start; ++i) {
		if ((*groupsp)[i] == nonlocal_users_group.gr_gid) {
		    is_nonlocal = true;
		    break;
		}
	    }

	    if (is_nonlocal) {
		struct passwd pwbuf;
		char *buf;
		int nonlocal_errno = *errnop;
		status = get_nonlocal_passwd(user, &pwbuf, &buf, errnop);

		if (status == NSS_STATUS_SUCCESS) {
		    nonlocal_errno = *errnop;
		    status = check_nonlocal_gid(user, pwbuf.pw_gid,
						&nonlocal_errno);
		    free(buf);
		}

		if (status == NSS_STATUS_SUCCESS) {
		    if (!add_group(pwbuf.pw_gid, start, size, groupsp, limit,
				   errnop, &status))
			return status;
		} else if (status == NSS_STATUS_TRYAGAIN) {
		    *errnop = nonlocal_errno;
		    return status;
		}
	    }
	}
    } else if (status == NSS_STATUS_TRYAGAIN) {
	if (is_nonlocal)
	    return status;
    } else {
	syslog(LOG_WARNING, "nss_nonlocal: Group %s does not exist locally!",
	       MAGIC_NONLOCAL_GROUPNAME);
    }

    if (!is_nonlocal)
	return NSS_STATUS_SUCCESS;

    in = out = *start;

#define args (user, group, start, size, groupsp, limit, errnop)
#include "walk_nss.h"
#undef args
    if (status != NSS_STATUS_SUCCESS)
        return status;

    for (; in < *start; ++in) {
	int nonlocal_errno = *errnop;

	for (i = 0; i < out; ++i)
	    if ((*groupsp)[i] == (*groupsp)[in])
		break;
	if (i < out)
	    continue;

	status = check_nonlocal_gid(user, (*groupsp)[in], &nonlocal_errno);
	if (status == NSS_STATUS_SUCCESS) {
	    (*groupsp)[out++] = (*groupsp)[in];
	} else if (status == NSS_STATUS_TRYAGAIN) {
	    *start = out;
	    *errnop = nonlocal_errno;
	    return status;
	}
    }

    *start = out;
    return NSS_STATUS_SUCCESS;
}
Commit	Line	Data
f6903667 AK	1	/*
	2	* nonlocal-group.c
	3	* group database for nss_nonlocal proxy
	4	*
96a1ee0f AK	5	* Copyright © 2007–2010 Anders Kaseorg <andersk@mit.edu> and Tim
96a1ee0f AK	6	* Abbott <tabbott@mit.edu>
f6903667	7	*
96a1ee0f	8	* This file is part of nss_nonlocal.
f6903667	9	*
96a1ee0f AK	10	* nss_nonlocal is free software; you can redistribute it and/or
	11	* modify it under the terms of the GNU Lesser General Public License
	12	* as published by the Free Software Foundation; either version 2.1 of
	13	* the License, or (at your option) any later version.
f6903667	14	*
96a1ee0f AK	15	* nss_nonlocal is distributed in the hope that it will be useful, but
	16	* WITHOUT ANY WARRANTY; without even the implied warranty of
	17	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	18	* Lesser General Public License for more details.
	19	*
	20	* You should have received a copy of the GNU Lesser General Public
	21	* License along with nss_nonlocal; if not, write to the Free Software
	22	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
	23	* 02110-1301 USA
f6903667 AK	24	*/
	25
	26	#define _GNU_SOURCE
	27	#include <sys/types.h>
	28	#include <unistd.h>
	29	#include <stdlib.h>
	30	#include <stdint.h>
	31	#include <string.h>
	32	#include <dlfcn.h>
	33	#include <stdio.h>
	34	#include <syslog.h>
	35	#include <errno.h>
775f7dc3	36	#include <pwd.h>
f6903667 AK	37	#include <grp.h>
	38	#include <nss.h>
	39	#include "nsswitch-internal.h"
	40	#include "nonlocal.h"
	41
6ca16423 AK	42	/*
6ca16423 AK	43	* If the MAGIC_NONLOCAL_GROUPNAME local group exists, then nonlocal
34cfeb28 AK	44	* users will be automatically added to it. Furthermore, if a local
34cfeb28 AK	45	* user is added to this group, then that user will inherit any
775f7dc3 AK	46	* nonlocal gids from a nonlocal user of the same name, as
775f7dc3 AK	47	* supplementary gids.
6ca16423	48	*/
48479fc7	49	#define MAGIC_NONLOCAL_GROUPNAME "nss-nonlocal-users"
6ca16423 AK	50
	51	/*
	52	* If the MAGIC_LOCAL_GROUPNAME local group exists, then local users
	53	* will be automatically added to it.
	54	*/
48479fc7	55	#define MAGIC_LOCAL_GROUPNAME "nss-local-users"
f7293a54	56
f6903667	57
c1812233 AK	58	enum nss_status
	59	_nss_nonlocal_getgrnam_r(const char name, struct group grp,
	60	char buffer, size_t buflen, int errnop);
	61
	62	enum nss_status
	63	_nss_nonlocal_getgrgid_r(gid_t gid, struct group *grp,
	64	char buffer, size_t buflen, int errnop);
	65
	66
cbb0e3ea AK	67	static service_user *__nss_group_nonlocal_database;
	68
	69	static int
	70	internal_function
	71	__nss_group_nonlocal_lookup(service_user *ni, const char fct_name,
	72	void **fctp)
f6903667	73	{
cbb0e3ea AK	74	if (__nss_group_nonlocal_database == NULL
	75	&& __nss_database_lookup("group_nonlocal", NULL, NULL,
	76	&__nss_group_nonlocal_database) < 0)
	77	return -1;
	78
	79	*ni = __nss_group_nonlocal_database;
48479fc7	80
cbb0e3ea AK	81	fctp = __nss_lookup_function(ni, fct_name);
cbb0e3ea AK	82	return 0;
f6903667 AK	83	}
	84
	85
f6903667 AK	86	enum nss_status
	87	check_nonlocal_gid(const char user, gid_t gid, int errnop)
	88	{
30fb3957	89	enum nss_status status;
f7293a54	90	struct group gbuf;
cbb0e3ea	91	char *buf;
8870ee9c	92	size_t buflen = sysconf(_SC_GETGR_R_SIZE_MAX);
cbb0e3ea AK	93	const struct walk_nss w = {
	94	.lookup = &__nss_group_lookup, .fct_name = "getgrgid_r",
	95	.status = &status, .errnop = errnop, .buf = &buf, .buflen = &buflen
	96	};
	97	const __typeof__(&_nss_nonlocal_getgrgid_r) self = &_nss_nonlocal_getgrgid_r;
	98	#define args (gid, &gbuf, buf, buflen, errnop)
	99	#include "walk_nss.h"
	100	#undef args
30fb3957 AK	101
30fb3957 AK	102	if (status == NSS_STATUS_SUCCESS) {
21b6ddd9	103	syslog(LOG_DEBUG, "nss_nonlocal: removing local group %u (%s) from non-local user %s\n", gbuf.gr_gid, gbuf.gr_name, user);
cbb0e3ea	104	free(buf);
f6903667	105	status = NSS_STATUS_NOTFOUND;
30fb3957 AK	106	} else if (status != NSS_STATUS_TRYAGAIN) {
30fb3957 AK	107	status = NSS_STATUS_SUCCESS;
f6903667	108	}
30fb3957	109
f6903667 AK	110	return status;
	111	}
	112
cf338316 AK	113	enum nss_status
	114	check_nonlocal_group(const char user, struct group grp, int *errnop)
	115	{
a07a7616 AK	116	enum nss_status status = NSS_STATUS_SUCCESS;
	117	int old_errno = errno;
	118	char *end;
	119	unsigned long gid;
	120
	121	errno = 0;
	122	gid = strtoul(grp->gr_name, &end, 10);
f4061d47 AK	123	if (errno == 0 && *end == '\0' && (gid_t)gid == gid) {
f4061d47 AK	124	errno = old_errno;
a07a7616	125	status = check_nonlocal_gid(user, gid, errnop);
f4061d47 AK	126	} else
f4061d47 AK	127	errno = old_errno;
a07a7616 AK	128	if (status != NSS_STATUS_SUCCESS)
	129	return status;
	130
cf338316 AK	131	return check_nonlocal_gid(user, grp->gr_gid, errnop);
	132	}
	133
48479fc7	134	enum nss_status
8aa9014e	135	get_local_group(const char name, struct group grp, char *buffer, int errnop)
48479fc7	136	{
30fb3957	137	enum nss_status status;
cbb0e3ea AK	138	size_t buflen = sysconf(_SC_GETGR_R_SIZE_MAX);
	139	const struct walk_nss w = {
	140	.lookup = &__nss_group_lookup, .fct_name = "getgrnam_r",
	141	.status = &status, .errnop = errnop, .buf = buffer, .buflen = &buflen
	142	};
	143	const __typeof__(&_nss_nonlocal_getgrnam_r) self = &_nss_nonlocal_getgrnam_r;
	144	#define args (name, grp, *buffer, buflen, errnop)
	145	#include "walk_nss.h"
	146	#undef args
48479fc7 TA	147	return status;
48479fc7 TA	148	}
f6903667	149
cbb0e3ea	150	static service_user grent_startp, grent_nip;
f6903667 AK	151	static void *grent_fct_start;
	152	static union {
	153	enum nss_status (l)(struct group grp, char *buffer, size_t buflen,
	154	int *errnop);
	155	void *ptr;
	156	} grent_fct;
	157	static const char *grent_fct_name = "getgrent_r";
	158
	159	enum nss_status
	160	_nss_nonlocal_setgrent(int stayopen)
	161	{
f6903667	162	enum nss_status status;
cbb0e3ea AK	163	const struct walk_nss w = {
	164	.lookup = &__nss_group_nonlocal_lookup, .fct_name = "setgrent",
	165	.status = &status
	166	};
	167	const __typeof__(&_nss_nonlocal_setgrent) self = NULL;
	168	#define args (stayopen)
	169	#include "walk_nss.h"
	170	#undef args
f6903667 AK	171	if (status != NSS_STATUS_SUCCESS)
	172	return status;
	173
f6903667	174	if (grent_fct_start == NULL)
cbb0e3ea AK	175	__nss_group_nonlocal_lookup(&grent_startp, grent_fct_name,
	176	&grent_fct_start);
	177	grent_nip = grent_startp;
f6903667 AK	178	grent_fct.ptr = grent_fct_start;
	179	return NSS_STATUS_SUCCESS;
	180	}
	181
	182	enum nss_status
	183	_nss_nonlocal_endgrent(void)
	184	{
f6903667	185	enum nss_status status;
cbb0e3ea AK	186	const struct walk_nss w = {
	187	.lookup = &__nss_group_nonlocal_lookup, .fct_name = "endgrent",
	188	.status = &status
	189	};
	190	const __typeof__(&_nss_nonlocal_endgrent) self = NULL;
f6903667 AK	191
	192	grent_nip = NULL;
	193
cbb0e3ea AK	194	#define args ()
	195	#include "walk_nss.h"
	196	#undef args
f6903667 AK	197	return status;
	198	}
	199
	200	enum nss_status
	201	_nss_nonlocal_getgrent_r(struct group grp, char buffer, size_t buflen,
	202	int *errnop)
	203	{
	204	enum nss_status status;
a360549e TA	205
a360549e TA	206	char *nonlocal_ignore = getenv(NONLOCAL_IGNORE_ENV);
c1812233	207	if (nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0')
a360549e TA	208	return NSS_STATUS_UNAVAIL;
a360549e TA	209
f6903667 AK	210	if (grent_nip == NULL) {
	211	status = _nss_nonlocal_setgrent(0);
	212	if (status != NSS_STATUS_SUCCESS)
	213	return status;
	214	}
	215	do {
	216	if (grent_fct.ptr == NULL)
	217	status = NSS_STATUS_UNAVAIL;
	218	else {
	219	int nonlocal_errno;
	220	do
	221	status = DL_CALL_FCT(grent_fct.l, (grp, buffer, buflen, errnop));
	222	while (status == NSS_STATUS_SUCCESS &&
cf338316	223	check_nonlocal_group("(unknown)", grp, &nonlocal_errno) != NSS_STATUS_SUCCESS);
f6903667 AK	224	}
	225	if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE)
	226	return status;
	227
	228	if (status == NSS_STATUS_SUCCESS)
	229	return NSS_STATUS_SUCCESS;
	230	} while (__nss_next(&grent_nip, grent_fct_name, &grent_fct.ptr, status, 0) == 0);
	231
	232	grent_nip = NULL;
	233	return NSS_STATUS_NOTFOUND;
	234	}
	235
	236
	237	enum nss_status
	238	_nss_nonlocal_getgrnam_r(const char name, struct group grp,
	239	char buffer, size_t buflen, int errnop)
	240	{
f6903667	241	enum nss_status status;
cbb0e3ea AK	242	const struct walk_nss w = {
	243	.lookup = &__nss_group_nonlocal_lookup, .fct_name = "getgrnam_r",
	244	.status = &status, .errnop = errnop
	245	};
	246	const __typeof__(&_nss_nonlocal_getgrnam_r) self = NULL;
f6903667	247
a360549e	248	char *nonlocal_ignore = getenv(NONLOCAL_IGNORE_ENV);
c1812233	249	if (nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0')
48479fc7 TA	250	return NSS_STATUS_UNAVAIL;
48479fc7 TA	251
cbb0e3ea AK	252	#define args (name, grp, buffer, buflen, errnop)
	253	#include "walk_nss.h"
	254	#undef args
f6903667 AK	255	if (status != NSS_STATUS_SUCCESS)
	256	return status;
	257
22562df0 AK	258	if (strcmp(name, grp->gr_name) != 0) {
	259	syslog(LOG_ERR, "nss_nonlocal: discarding group %s from lookup for group %s\n", grp->gr_name, name);
	260	return NSS_STATUS_NOTFOUND;
	261	}
	262
cf338316	263	return check_nonlocal_group(name, grp, errnop);
f6903667 AK	264	}
	265
	266	enum nss_status
	267	_nss_nonlocal_getgrgid_r(gid_t gid, struct group *grp,
	268	char buffer, size_t buflen, int errnop)
	269	{
f6903667	270	enum nss_status status;
cbb0e3ea AK	271	const struct walk_nss w = {
	272	.lookup = &__nss_group_nonlocal_lookup, .fct_name = "getgrgid_r",
	273	.status = &status, .errnop = errnop
	274	};
	275	const __typeof__(&_nss_nonlocal_getgrgid_r) self = NULL;
f6903667	276
a360549e	277	char *nonlocal_ignore = getenv(NONLOCAL_IGNORE_ENV);
c1812233	278	if (nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0')
f6903667 AK	279	return NSS_STATUS_UNAVAIL;
f6903667 AK	280
cbb0e3ea AK	281	#define args (gid, grp, buffer, buflen, errnop)
	282	#include "walk_nss.h"
	283	#undef args
f6903667 AK	284	if (status != NSS_STATUS_SUCCESS)
	285	return status;
	286
8027fdc4 AK	287	if (gid != grp->gr_gid) {
	288	syslog(LOG_ERR, "nss_nonlocal: discarding gid %d from lookup for gid %d\n", grp->gr_gid, gid);
	289	return NSS_STATUS_NOTFOUND;
	290	}
	291
cf338316	292	return check_nonlocal_group(grp->gr_name, grp, errnop);
f6903667 AK	293	}
f6903667 AK	294
dfc6e292 AK	295	static bool
	296	add_group(gid_t group, long int start, long int size, gid_t **groupsp,
	297	long int limit, int errnop, enum nss_status status)
	298	{
	299	int i, old_errno = errno;
	300	for (i = 0; i < *start; ++i)
	301	if ((*groupsp)[i] == group)
	302	return true;
	303	if (start + 1 > size) {
	304	gid_t *newgroups;
	305	long int newsize = 2 * *size;
	306	if (limit > 0) {
	307	if (*size >= limit) {
	308	*status = NSS_STATUS_SUCCESS;
	309	return false;
	310	}
	311	if (newsize > limit)
	312	newsize = limit;
	313	}
	314	newgroups = realloc(groupsp, newsize sizeof((*groupsp)[0]));
	315	errno = old_errno;
	316	if (newgroups == NULL) {
	317	*errnop = ENOMEM;
	318	*status = NSS_STATUS_TRYAGAIN;
	319	return false;
	320	}
	321	*groupsp = newgroups;
	322	*size = newsize;
	323	}
	324	(groupsp)[(start)++] = group;
	325	return true;
	326	}
	327
f6903667 AK	328	enum nss_status
	329	_nss_nonlocal_initgroups_dyn(const char user, gid_t group, long int start,
	330	long int size, gid_t *groupsp, long int limit,
	331	int *errnop)
	332	{
f6903667	333	enum nss_status status;
cbb0e3ea AK	334	const struct walk_nss w = {
	335	.lookup = &__nss_group_nonlocal_lookup, .fct_name = "initgroups_dyn",
	336	.status = &status, .errnop = errnop
	337	};
	338	const __typeof__(&_nss_nonlocal_initgroups_dyn) self = NULL;
1e78305d AK	339
1e78305d AK	340	struct group local_users_group, nonlocal_users_group;
b3831d60	341	bool is_nonlocal = true;
1e78305d	342	char *buffer;
d7bf1d11	343	int in, out, i;
48479fc7	344
34cfeb28 AK	345	/* Check that the user is a nonlocal user, or a member of the
34cfeb28 AK	346	* MAGIC_NONLOCAL_GROUPNAME group, before adding any groups. */
48479fc7	347	status = check_nonlocal_user(user, errnop);
3010a54b	348	if (status == NSS_STATUS_TRYAGAIN) {
48479fc7	349	return status;
3010a54b	350	} else if (status != NSS_STATUS_SUCCESS) {
b3831d60	351	is_nonlocal = false;
48479fc7	352
3010a54b AK	353	status = get_local_group(MAGIC_LOCAL_GROUPNAME,
	354	&local_users_group, &buffer, errnop);
	355	if (status == NSS_STATUS_SUCCESS) {
	356	free(buffer);
	357	if (!add_group(local_users_group.gr_gid, start, size, groupsp,
	358	limit, errnop, &status))
	359	return status;
	360	} else if (status == NSS_STATUS_TRYAGAIN) {
dfc6e292	361	return status;
3010a54b AK	362	} else {
	363	syslog(LOG_WARNING,
	364	"nss_nonlocal: Group %s does not exist locally!",
	365	MAGIC_LOCAL_GROUPNAME);
	366	}
a4e1e153 AK	367	}
	368
	369	status = get_local_group(MAGIC_NONLOCAL_GROUPNAME,
	370	&nonlocal_users_group, &buffer, errnop);
	371	if (status == NSS_STATUS_SUCCESS) {
	372	free(buffer);
	373	if (is_nonlocal) {
dfc6e292 AK	374	if (!add_group(nonlocal_users_group.gr_gid, start, size, groupsp,
	375	limit, errnop, &status))
	376	return status;
34cfeb28 AK	377	} else {
	378	int i;
	379	for (i = 0; i < *start; ++i) {
	380	if ((*groupsp)[i] == nonlocal_users_group.gr_gid) {
	381	is_nonlocal = true;
	382	break;
	383	}
	384	}
775f7dc3 AK	385
	386	if (is_nonlocal) {
	387	struct passwd pwbuf;
	388	char *buf;
	389	int nonlocal_errno = *errnop;
	390	status = get_nonlocal_passwd(user, &pwbuf, &buf, errnop);
	391
	392	if (status == NSS_STATUS_SUCCESS) {
	393	nonlocal_errno = *errnop;
	394	status = check_nonlocal_gid(user, pwbuf.pw_gid,
	395	&nonlocal_errno);
	396	free(buf);
	397	}
	398
	399	if (status == NSS_STATUS_SUCCESS) {
	400	if (!add_group(pwbuf.pw_gid, start, size, groupsp, limit,
	401	errnop, &status))
	402	return status;
	403	} else if (status == NSS_STATUS_TRYAGAIN) {
	404	*errnop = nonlocal_errno;
	405	return status;
	406	}
	407	}
1e78305d	408	}
a4e1e153 AK	409	} else if (status == NSS_STATUS_TRYAGAIN) {
	410	if (is_nonlocal)
	411	return status;
	412	} else {
	413	syslog(LOG_WARNING, "nss_nonlocal: Group %s does not exist locally!",
	414	MAGIC_NONLOCAL_GROUPNAME);
48479fc7	415	}
f6903667	416
b3831d60	417	if (!is_nonlocal)
1e78305d AK	418	return NSS_STATUS_SUCCESS;
1e78305d AK	419
d7bf1d11	420	in = out = *start;
1e78305d	421
cbb0e3ea AK	422	#define args (user, group, start, size, groupsp, limit, errnop)
	423	#include "walk_nss.h"
	424	#undef args
f6903667 AK	425	if (status != NSS_STATUS_SUCCESS)
	426	return status;
	427
	428	for (; in < *start; ++in) {
	429	int nonlocal_errno = *errnop;
	430
	431	for (i = 0; i < out; ++i)
	432	if ((groupsp)[i] == (groupsp)[in])
	433	break;
	434	if (i < out)
	435	continue;
	436
	437	status = check_nonlocal_gid(user, (*groupsp)[in], &nonlocal_errno);
	438	if (status == NSS_STATUS_SUCCESS) {
1e78305d	439	(groupsp)[out++] = (groupsp)[in];
5879a696	440	} else if (status == NSS_STATUS_TRYAGAIN) {
f6903667 AK	441	*start = out;
	442	*errnop = nonlocal_errno;
	443	return status;
	444	}
	445	}
	446
	447	*start = out;
	448	return NSS_STATUS_SUCCESS;
	449	}