[nss_nonlocal.git] / nonlocal-group.c

/*
 * nonlocal-group.c
 * group database for nss_nonlocal proxy
 *
 * Copyright © 2007 Anders Kaseorg <andersk@mit.edu> and Tim Abbott
 * <tabbott@mit.edu>
 *
 * Permission is hereby granted, free of charge, to any person
 * obtaining a copy of this software and associated documentation
 * files (the "Software"), to deal in the Software without
 * restriction, including without limitation the rights to use, copy,
 * modify, merge, publish, distribute, sublicense, and/or sell copies
 * of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#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 <grp.h>
#include <nss.h>
#include "nsswitch-internal.h"
#include "nonlocal.h"

#define MAGIC_LOCAL_GR_BUFLEN (sysconf(_SC_GETGR_R_SIZE_MAX) + 7)
#define MAGIC_NONLOCAL_GROUPNAME "nss-nonlocal-users"
#define MAGIC_LOCAL_GROUPNAME "nss-local-users"


static service_user *
nss_group_nonlocal_database(void)
{
    static service_user *nip = NULL;
    if (nip == NULL)
	__nss_database_lookup("group_nonlocal", NULL, "", &nip);

    return nip;
}


enum nss_status
check_nonlocal_gid(const char *user, gid_t gid, int *errnop)
{
    enum nss_status status = NSS_STATUS_SUCCESS;
    struct group gbuf;
    struct group *gbufp = &gbuf;
    int ret;
    int old_errno = errno;
    int buflen = MAGIC_LOCAL_GR_BUFLEN;
    char *buf = malloc(buflen);
    if (buf == NULL) {
	*errnop = ENOMEM;
	errno = old_errno;
	return NSS_STATUS_TRYAGAIN;
    }
    errno = 0;
    ret = getgrgid_r(gid, gbufp, buf, buflen, &gbufp);
    if (ret != 0) {
	*errnop = old_errno;
	status = NSS_STATUS_TRYAGAIN;
    } else if (gbufp != NULL) {
	syslog(LOG_WARNING, "nss_nonlocal: removing local group %u (%s) from non-local user %s\n", gbuf.gr_gid, gbuf.gr_name, user);
	status = NSS_STATUS_NOTFOUND;
    }
    free(buf);
    errno = old_errno;
    return status;
}

enum nss_status
get_local_group(const char *name, struct group *grp, char *buffer, size_t buflen, int *errnop)
{
    enum nss_status status = NSS_STATUS_NOTFOUND;
    struct group gbuf;
    struct group *gbufp = &gbuf;
    int ret, n;
    int old_errno = errno;
    int len = MAGIC_LOCAL_GR_BUFLEN;
    char *buf = malloc(len);
    if (buf == NULL) {
	*errnop = ENOMEM;
	errno = old_errno;
	return NSS_STATUS_TRYAGAIN;
    }
    errno = 0;
    ret = getgrnam_r(name, gbufp, buf, len, &gbufp);
    if (ret != 0) {
	*errnop = old_errno;
	status = NSS_STATUS_TRYAGAIN;
    } else if (gbufp != NULL) {
	status = NSS_STATUS_SUCCESS;

	n = snprintf(buffer, buflen, "%s", gbufp->gr_name);
	if (n < 0 || n >= buflen) {
	    *errnop = ERANGE;
	    status = NSS_STATUS_TRYAGAIN;
	    goto get_local_group_done;
	}
	grp->gr_name = buffer;
	buffer += n;
	buflen -= n;

	n = snprintf(buffer, buflen, "%s", gbufp->gr_passwd);
	if (n < 0 || n >= buflen) {
	    *errnop = ERANGE;
	    status = NSS_STATUS_TRYAGAIN;
	    goto get_local_group_done;
	}
	grp->gr_passwd = buffer;
	buffer += n;
	buflen -= n;

	grp->gr_gid = gbufp->gr_gid;

	if (buflen < sizeof(void *)) {
	    *errnop = ERANGE;
	    status = NSS_STATUS_TRYAGAIN;
	    goto get_local_group_done;
	}
	*(void **)buffer = NULL;
	buffer += sizeof(void *);
	buflen -= sizeof(void *);
    }
 get_local_group_done:
    free(buf);
    errno = old_errno;
    return status;
}

static service_user *grent_nip = NULL;
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)
{
    static const char *fct_name = "setgrent";
    static void *fct_start = NULL;
    enum nss_status status;
    service_user *nip;
    union {
	enum nss_status (*l)(int stayopen);
	void *ptr;
    } fct;

    nip = nss_group_nonlocal_database();
    if (nip == NULL)
	return NSS_STATUS_UNAVAIL;
    if (fct_start == NULL)
	fct_start = __nss_lookup_function(nip, fct_name);
    fct.ptr = fct_start;
    do {
	if (fct.ptr == NULL)
	    status = NSS_STATUS_UNAVAIL;
	else
	    status = DL_CALL_FCT(fct.l, (stayopen));
    } while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
    if (status != NSS_STATUS_SUCCESS)
	return status;

    grent_nip = nip;
    if (grent_fct_start == NULL)
	grent_fct_start = __nss_lookup_function(nip, grent_fct_name);
    grent_fct.ptr = grent_fct_start;
    return NSS_STATUS_SUCCESS;
}

enum nss_status
_nss_nonlocal_endgrent(void)
{
    static const char *fct_name = "endgrent";
    static void *fct_start = NULL;
    enum nss_status status;
    service_user *nip;
    union {
	enum nss_status (*l)(void);
	void *ptr;
    } fct;

    grent_nip = NULL;

    nip = nss_group_nonlocal_database();
    if (nip == NULL)
	return NSS_STATUS_UNAVAIL;
    if (fct_start == NULL)
	fct_start = __nss_lookup_function(nip, fct_name);
    fct.ptr = fct_start;
    do {
	if (fct.ptr == NULL)
	    status = NSS_STATUS_UNAVAIL;
	else
	    status = DL_CALL_FCT(fct.l, ());
    } while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
    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 (buflen == MAGIC_LOCAL_GR_BUFLEN ||
	(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_gid("(unknown)", grp->gr_gid, &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)
{
    static const char *fct_name = "getgrnam_r";
    static void *fct_start = NULL;
    enum nss_status status;
    service_user *nip;
    union {
	enum nss_status (*l)(const char *name, struct group *grp,
			     char *buffer, size_t buflen, int *errnop);
	void *ptr;
    } fct;

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

    nip = nss_group_nonlocal_database();
    if (nip == NULL)
	return NSS_STATUS_UNAVAIL;
    if (fct_start == NULL)
	fct_start = __nss_lookup_function(nip, fct_name);
    fct.ptr = fct_start;
    do {
	if (fct.ptr == NULL)
	    status = NSS_STATUS_UNAVAIL;
	else
	    status = DL_CALL_FCT(fct.l, (name, grp, buffer, buflen, errnop));
	if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE)
	    break;
    } while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
    if (status != NSS_STATUS_SUCCESS)
	return status;

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

enum nss_status
_nss_nonlocal_getgrgid_r(gid_t gid, struct group *grp,
			 char *buffer, size_t buflen, int *errnop)
{
    static const char *fct_name = "getgrgid_r";
    static void *fct_start = NULL;
    enum nss_status status;
    service_user *nip;
    union {
	enum nss_status (*l)(gid_t gid, struct group *grp,
			     char *buffer, size_t buflen, int *errnop);
	void *ptr;
    } fct;

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

    nip = nss_group_nonlocal_database();
    if (nip == NULL)
	return NSS_STATUS_UNAVAIL;
    if (fct_start == NULL)
	fct_start = __nss_lookup_function(nip, fct_name);
    fct.ptr = fct_start;
    do {
	if (fct.ptr == NULL)
	    status = NSS_STATUS_UNAVAIL;
	else
	    status = DL_CALL_FCT(fct.l, (gid, grp, buffer, buflen, errnop));
	if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE)
	    break;
    } while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
    if (status != NSS_STATUS_SUCCESS)
	return status;

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

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)
{
    static const char *fct_name = "initgroups_dyn";
    static void *fct_start = NULL;
    enum nss_status status;
    service_user *nip;
    union {
	enum nss_status (*l)(const char *user, gid_t group, long int *start,
			     long int *size, gid_t **groupsp, long int limit,
			     int *errnop);
	void *ptr;
    } fct;

    struct group local_users_group, nonlocal_users_group;
    gid_t local_users_gid, gid;
    int is_local = 0;
    int buflen;
    char *buffer;

    /* Check that the user is a nonlocal user before adding any groups. */
    status = check_nonlocal_user(user, errnop);
    if (status == NSS_STATUS_NOTFOUND)
	is_local = 1;
    else if (status != NSS_STATUS_SUCCESS)
	return status;

    int old_errno = errno;

    buflen = sysconf(_SC_GETGR_R_SIZE_MAX);
    buffer = malloc(buflen);
    if (buffer == NULL) {
	*errnop = ENOMEM;
	errno = old_errno;
	return NSS_STATUS_TRYAGAIN;
    }
    status = get_local_group(MAGIC_LOCAL_GROUPNAME,
			     &local_users_group, buffer, buflen, errnop);
    if (status == NSS_STATUS_NOTFOUND) {
	syslog(LOG_WARNING, "nss_nonlocal: Group %s does not exist locally!",
	       MAGIC_LOCAL_GROUPNAME);
	local_users_gid = -1;
    } else if (status != NSS_STATUS_SUCCESS) {
	return status;
    } else
	local_users_gid = local_users_group.gr_gid;
    free(buffer);

    if (is_local) {
	gid = local_users_gid;
    } else {
	buflen = sysconf(_SC_GETGR_R_SIZE_MAX);
	buffer = malloc(buflen);
	if (buffer == NULL) {
	    *errnop = ENOMEM;
	    errno = old_errno;
	    return NSS_STATUS_TRYAGAIN;
	}
 	status = get_local_group(MAGIC_NONLOCAL_GROUPNAME,
				 &nonlocal_users_group, buffer, buflen, errnop);
	if (status == NSS_STATUS_NOTFOUND) {
	    syslog(LOG_WARNING, "nss_nonlocal: Group %s does not exist locally!",
		   MAGIC_NONLOCAL_GROUPNAME);
	    gid = -1;
	} else if (status != NSS_STATUS_SUCCESS) {
	    errno = old_errno;
	    return status;
	} else
	    gid = nonlocal_users_group.gr_gid;
	free(buffer);
    }

    if (gid != -1) {
	int i;
	for (i = 0; i < *start; ++i)
	    if ((*groupsp)[i] == gid)
		break;
	if (i >= *start) {
	    if (*start + 1 > *size) {
		gid_t *newgroups;
		long int newsize = 2 * *size;
		if (limit > 0) {
		    if (*size >= limit)
			return NSS_STATUS_SUCCESS;
		    if (newsize > limit)
			newsize = limit;
		}
		newgroups = realloc(*groupsp, *size * sizeof((*groupsp)[0]));
		if (newgroups == NULL) {
		    *errnop = ENOMEM;
		    errno = old_errno;
		    return NSS_STATUS_TRYAGAIN;
		}
		*groupsp = newgroups;
		*size = newsize;
	    }
	    (*groupsp)[(*start)++] = gid;
	}
    }

    errno = old_errno;

    if (is_local)
	return NSS_STATUS_SUCCESS;

    int in = *start, out = *start, i;

    nip = nss_group_nonlocal_database();
    if (nip == NULL)
	return NSS_STATUS_UNAVAIL;
    if (fct_start == NULL)
	fct_start = __nss_lookup_function(nip, fct_name);
    fct.ptr = fct_start;

    do {
	if (fct.ptr == NULL)
	    status = NSS_STATUS_UNAVAIL;
	else
	    status = DL_CALL_FCT(fct.l, (user, group, start, size, groupsp, limit, errnop));
        if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE)
            break;
    } while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
    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;

	/* Don't let users get into MAGIC_LOCAL_GROUPNAME from nonlocal reasons. */
	if (local_users_gid == (*groupsp)[in]) {
	    syslog(LOG_WARNING, "nss_nonlocal: Nonlocal user %s removed from special local users group %s",
		   user, MAGIC_LOCAL_GROUPNAME);
	    continue;
	}

	status = check_nonlocal_gid(user, (*groupsp)[in], &nonlocal_errno);
	if (status == NSS_STATUS_SUCCESS) {
	    (*groupsp)[out++] = (*groupsp)[in];
	} else if (status != NSS_STATUS_NOTFOUND) {
	    *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	*
48479fc7 TA	5	* Copyright © 2007 Anders Kaseorg <andersk@mit.edu> and Tim Abbott
48479fc7 TA	6	* <tabbott@mit.edu>
f6903667 AK	7	*
	8	* Permission is hereby granted, free of charge, to any person
	9	* obtaining a copy of this software and associated documentation
	10	* files (the "Software"), to deal in the Software without
	11	* restriction, including without limitation the rights to use, copy,
	12	* modify, merge, publish, distribute, sublicense, and/or sell copies
	13	* of the Software, and to permit persons to whom the Software is
	14	* furnished to do so, subject to the following conditions:
	15	*
	16	* The above copyright notice and this permission notice shall be
	17	* included in all copies or substantial portions of the Software.
	18	*
	19	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	20	* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	21	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
	22	* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
	23	* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
	24	* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
	25	* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	26	* SOFTWARE.
	27	*/
	28
	29	#define _GNU_SOURCE
	30	#include <sys/types.h>
	31	#include <unistd.h>
	32	#include <stdlib.h>
	33	#include <stdint.h>
	34	#include <string.h>
	35	#include <dlfcn.h>
	36	#include <stdio.h>
	37	#include <syslog.h>
	38	#include <errno.h>
	39	#include <grp.h>
	40	#include <nss.h>
	41	#include "nsswitch-internal.h"
	42	#include "nonlocal.h"
	43
f7293a54	44	#define MAGIC_LOCAL_GR_BUFLEN (sysconf(_SC_GETGR_R_SIZE_MAX) + 7)
48479fc7 TA	45	#define MAGIC_NONLOCAL_GROUPNAME "nss-nonlocal-users"
48479fc7 TA	46	#define MAGIC_LOCAL_GROUPNAME "nss-local-users"
f7293a54	47
f6903667 AK	48
	49	static service_user *
	50	nss_group_nonlocal_database(void)
	51	{
	52	static service_user *nip = NULL;
	53	if (nip == NULL)
	54	__nss_database_lookup("group_nonlocal", NULL, "", &nip);
48479fc7	55
f6903667 AK	56	return nip;
	57	}
	58
	59
f6903667 AK	60	enum nss_status
	61	check_nonlocal_gid(const char user, gid_t gid, int errnop)
	62	{
f7293a54 AK	63	enum nss_status status = NSS_STATUS_SUCCESS;
	64	struct group gbuf;
	65	struct group *gbufp = &gbuf;
	66	int ret;
	67	int old_errno = errno;
	68	int buflen = MAGIC_LOCAL_GR_BUFLEN;
	69	char *buf = malloc(buflen);
	70	if (buf == NULL) {
f6903667	71	*errnop = ENOMEM;
f7293a54	72	errno = old_errno;
f6903667 AK	73	return NSS_STATUS_TRYAGAIN;
f6903667 AK	74	}
f7293a54 AK	75	errno = 0;
	76	ret = getgrgid_r(gid, gbufp, buf, buflen, &gbufp);
	77	if (ret != 0) {
	78	*errnop = old_errno;
	79	status = NSS_STATUS_TRYAGAIN;
	80	} else if (gbufp != NULL) {
	81	syslog(LOG_WARNING, "nss_nonlocal: removing local group %u (%s) from non-local user %s\n", gbuf.gr_gid, gbuf.gr_name, user);
f6903667	82	status = NSS_STATUS_NOTFOUND;
f6903667	83	}
f7293a54 AK	84	free(buf);
f7293a54 AK	85	errno = old_errno;
f6903667 AK	86	return status;
	87	}
	88
48479fc7 TA	89	enum nss_status
	90	get_local_group(const char name, struct group grp, char buffer, size_t buflen, int errnop)
	91	{
	92	enum nss_status status = NSS_STATUS_NOTFOUND;
	93	struct group gbuf;
	94	struct group *gbufp = &gbuf;
1e78305d	95	int ret, n;
48479fc7 TA	96	int old_errno = errno;
	97	int len = MAGIC_LOCAL_GR_BUFLEN;
	98	char *buf = malloc(len);
	99	if (buf == NULL) {
	100	*errnop = ENOMEM;
	101	errno = old_errno;
	102	return NSS_STATUS_TRYAGAIN;
	103	}
	104	errno = 0;
	105	ret = getgrnam_r(name, gbufp, buf, len, &gbufp);
	106	if (ret != 0) {
	107	*errnop = old_errno;
	108	status = NSS_STATUS_TRYAGAIN;
	109	} else if (gbufp != NULL) {
	110	status = NSS_STATUS_SUCCESS;
1e78305d AK	111
	112	n = snprintf(buffer, buflen, "%s", gbufp->gr_name);
	113	if (n < 0 \|\| n >= buflen) {
	114	*errnop = ERANGE;
	115	status = NSS_STATUS_TRYAGAIN;
	116	goto get_local_group_done;
	117	}
	118	grp->gr_name = buffer;
	119	buffer += n;
	120	buflen -= n;
	121
	122	n = snprintf(buffer, buflen, "%s", gbufp->gr_passwd);
	123	if (n < 0 \|\| n >= buflen) {
	124	*errnop = ERANGE;
	125	status = NSS_STATUS_TRYAGAIN;
	126	goto get_local_group_done;
	127	}
	128	grp->gr_passwd = buffer;
	129	buffer += n;
	130	buflen -= n;
	131
48479fc7	132	grp->gr_gid = gbufp->gr_gid;
1e78305d	133
48479fc7 TA	134	if (buflen < sizeof(void *)) {
	135	*errnop = ERANGE;
	136	status = NSS_STATUS_TRYAGAIN;
1e78305d	137	goto get_local_group_done;
48479fc7	138	}
1e78305d AK	139	(void *)buffer = NULL;
	140	buffer += sizeof(void *);
	141	buflen -= sizeof(void *);
48479fc7	142	}
1e78305d	143	get_local_group_done:
48479fc7 TA	144	free(buf);
	145	errno = old_errno;
	146	return status;
	147	}
f6903667 AK	148
	149	static service_user *grent_nip = NULL;
	150	static void *grent_fct_start;
	151	static union {
	152	enum nss_status (l)(struct group grp, char *buffer, size_t buflen,
	153	int *errnop);
	154	void *ptr;
	155	} grent_fct;
	156	static const char *grent_fct_name = "getgrent_r";
	157
	158	enum nss_status
	159	_nss_nonlocal_setgrent(int stayopen)
	160	{
	161	static const char *fct_name = "setgrent";
	162	static void *fct_start = NULL;
	163	enum nss_status status;
	164	service_user *nip;
	165	union {
	166	enum nss_status (*l)(int stayopen);
	167	void *ptr;
	168	} fct;
	169
	170	nip = nss_group_nonlocal_database();
	171	if (nip == NULL)
	172	return NSS_STATUS_UNAVAIL;
	173	if (fct_start == NULL)
	174	fct_start = __nss_lookup_function(nip, fct_name);
	175	fct.ptr = fct_start;
	176	do {
	177	if (fct.ptr == NULL)
	178	status = NSS_STATUS_UNAVAIL;
	179	else
	180	status = DL_CALL_FCT(fct.l, (stayopen));
	181	} while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
	182	if (status != NSS_STATUS_SUCCESS)
	183	return status;
	184
	185	grent_nip = nip;
	186	if (grent_fct_start == NULL)
	187	grent_fct_start = __nss_lookup_function(nip, grent_fct_name);
	188	grent_fct.ptr = grent_fct_start;
	189	return NSS_STATUS_SUCCESS;
	190	}
	191
	192	enum nss_status
	193	_nss_nonlocal_endgrent(void)
	194	{
	195	static const char *fct_name = "endgrent";
	196	static void *fct_start = NULL;
	197	enum nss_status status;
	198	service_user *nip;
	199	union {
	200	enum nss_status (*l)(void);
	201	void *ptr;
	202	} fct;
	203
	204	grent_nip = NULL;
	205
	206	nip = nss_group_nonlocal_database();
	207	if (nip == NULL)
	208	return NSS_STATUS_UNAVAIL;
	209	if (fct_start == NULL)
	210	fct_start = __nss_lookup_function(nip, fct_name);
	211	fct.ptr = fct_start;
212	do {
213	if (fct.ptr == NULL)
214	status = NSS_STATUS_UNAVAIL;
215	else
216	status = DL_CALL_FCT(fct.l, ());
217	} while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
218	return status;
219	}
220
221	enum nss_status
222	_nss_nonlocal_getgrent_r(struct group grp, char buffer, size_t buflen,
223	int *errnop)
224	{
225	enum nss_status status;
a360549e TA	226
	227	char *nonlocal_ignore = getenv(NONLOCAL_IGNORE_ENV);
	228	if (buflen == MAGIC_LOCAL_GR_BUFLEN \|\|
	229	(nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0'))
	230	return NSS_STATUS_UNAVAIL;
	231
f6903667 AK	232	if (grent_nip == NULL) {
	233	status = _nss_nonlocal_setgrent(0);
	234	if (status != NSS_STATUS_SUCCESS)
	235	return status;
	236	}
	237	do {
	238	if (grent_fct.ptr == NULL)
	239	status = NSS_STATUS_UNAVAIL;
	240	else {
	241	int nonlocal_errno;
	242	do
	243	status = DL_CALL_FCT(grent_fct.l, (grp, buffer, buflen, errnop));
	244	while (status == NSS_STATUS_SUCCESS &&
	245	check_nonlocal_gid("(unknown)", grp->gr_gid, &nonlocal_errno) != NSS_STATUS_SUCCESS);
	246	}
	247	if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE)
	248	return status;
	249
	250	if (status == NSS_STATUS_SUCCESS)
	251	return NSS_STATUS_SUCCESS;
	252	} while (__nss_next(&grent_nip, grent_fct_name, &grent_fct.ptr, status, 0) == 0);
	253
	254	grent_nip = NULL;
	255	return NSS_STATUS_NOTFOUND;
	256	}
	257
	258
	259	enum nss_status
	260	_nss_nonlocal_getgrnam_r(const char name, struct group grp,
	261	char buffer, size_t buflen, int errnop)
	262	{
	263	static const char *fct_name = "getgrnam_r";
	264	static void *fct_start = NULL;
	265	enum nss_status status;
	266	service_user *nip;
	267	union {
	268	enum nss_status (l)(const char name, struct group *grp,
	269	char buffer, size_t buflen, int errnop);
	270	void *ptr;
	271	} fct;
	272
a360549e TA	273	char *nonlocal_ignore = getenv(NONLOCAL_IGNORE_ENV);
	274	if (buflen == MAGIC_LOCAL_GR_BUFLEN \|\|
	275	(nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0'))
48479fc7 TA	276	return NSS_STATUS_UNAVAIL;
48479fc7 TA	277
f6903667 AK	278	nip = nss_group_nonlocal_database();
	279	if (nip == NULL)
	280	return NSS_STATUS_UNAVAIL;
	281	if (fct_start == NULL)
	282	fct_start = __nss_lookup_function(nip, fct_name);
	283	fct.ptr = fct_start;
	284	do {
	285	if (fct.ptr == NULL)
	286	status = NSS_STATUS_UNAVAIL;
	287	else
	288	status = DL_CALL_FCT(fct.l, (name, grp, buffer, buflen, errnop));
	289	if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE)
	290	break;
	291	} while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
	292	if (status != NSS_STATUS_SUCCESS)
	293	return status;
	294
	295	return check_nonlocal_gid(name, grp->gr_gid, errnop);
	296	}
	297
	298	enum nss_status
	299	_nss_nonlocal_getgrgid_r(gid_t gid, struct group *grp,
	300	char buffer, size_t buflen, int errnop)
	301	{
	302	static const char *fct_name = "getgrgid_r";
	303	static void *fct_start = NULL;
	304	enum nss_status status;
	305	service_user *nip;
	306	union {
	307	enum nss_status (l)(gid_t gid, struct group grp,
	308	char buffer, size_t buflen, int errnop);
	309	void *ptr;
	310	} fct;
	311
a360549e TA	312	char *nonlocal_ignore = getenv(NONLOCAL_IGNORE_ENV);
	313	if (buflen == MAGIC_LOCAL_GR_BUFLEN \|\|
	314	(nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0'))
f6903667 AK	315	return NSS_STATUS_UNAVAIL;
	316
	317	nip = nss_group_nonlocal_database();
	318	if (nip == NULL)
	319	return NSS_STATUS_UNAVAIL;
	320	if (fct_start == NULL)
	321	fct_start = __nss_lookup_function(nip, fct_name);
	322	fct.ptr = fct_start;
	323	do {
	324	if (fct.ptr == NULL)
	325	status = NSS_STATUS_UNAVAIL;
	326	else
	327	status = DL_CALL_FCT(fct.l, (gid, grp, buffer, buflen, errnop));
	328	if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE)
	329	break;
	330	} while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
	331	if (status != NSS_STATUS_SUCCESS)
	332	return status;
	333
	334	return check_nonlocal_gid(grp->gr_name, grp->gr_gid, errnop);
	335	}
	336
	337	enum nss_status
	338	_nss_nonlocal_initgroups_dyn(const char user, gid_t group, long int start,
	339	long int size, gid_t *groupsp, long int limit,
	340	int *errnop)
	341	{
	342	static const char *fct_name = "initgroups_dyn";
	343	static void *fct_start = NULL;
	344	enum nss_status status;
	345	service_user *nip;
	346	union {
	347	enum nss_status (l)(const char user, gid_t group, long int *start,
	348	long int size, gid_t *groupsp, long int limit,
	349	int *errnop);
	350	void *ptr;
	351	} fct;
1e78305d AK	352
	353	struct group local_users_group, nonlocal_users_group;
	354	gid_t local_users_gid, gid;
48479fc7	355	int is_local = 0;
1e78305d AK	356	int buflen;
1e78305d AK	357	char *buffer;
48479fc7	358
1e78305d	359	/* Check that the user is a nonlocal user before adding any groups. */
48479fc7	360	status = check_nonlocal_user(user, errnop);
1e78305d	361	if (status == NSS_STATUS_NOTFOUND)
48479fc7	362	is_local = 1;
1e78305d	363	else if (status != NSS_STATUS_SUCCESS)
48479fc7	364	return status;
48479fc7	365
1e78305d AK	366	int old_errno = errno;
	367
	368	buflen = sysconf(_SC_GETGR_R_SIZE_MAX);
	369	buffer = malloc(buflen);
48479fc7 TA	370	if (buffer == NULL) {
48479fc7 TA	371	*errnop = ENOMEM;
1e78305d	372	errno = old_errno;
48479fc7 TA	373	return NSS_STATUS_TRYAGAIN;
48479fc7 TA	374	}
48479fc7 TA	375	status = get_local_group(MAGIC_LOCAL_GROUPNAME,
48479fc7 TA	376	&local_users_group, buffer, buflen, errnop);
48479fc7 TA	377	if (status == NSS_STATUS_NOTFOUND) {
	378	syslog(LOG_WARNING, "nss_nonlocal: Group %s does not exist locally!",
	379	MAGIC_LOCAL_GROUPNAME);
1e78305d AK	380	local_users_gid = -1;
	381	} else if (status != NSS_STATUS_SUCCESS) {
	382	return status;
	383	} else
	384	local_users_gid = local_users_group.gr_gid;
	385	free(buffer);
	386
	387	if (is_local) {
	388	gid = local_users_gid;
	389	} else {
	390	buflen = sysconf(_SC_GETGR_R_SIZE_MAX);
	391	buffer = malloc(buflen);
	392	if (buffer == NULL) {
	393	*errnop = ENOMEM;
	394	errno = old_errno;
	395	return NSS_STATUS_TRYAGAIN;
48479fc7	396	}
1e78305d AK	397	status = get_local_group(MAGIC_NONLOCAL_GROUPNAME,
	398	&nonlocal_users_group, buffer, buflen, errnop);
	399	if (status == NSS_STATUS_NOTFOUND) {
	400	syslog(LOG_WARNING, "nss_nonlocal: Group %s does not exist locally!",
	401	MAGIC_NONLOCAL_GROUPNAME);
	402	gid = -1;
	403	} else if (status != NSS_STATUS_SUCCESS) {
	404	errno = old_errno;
	405	return status;
	406	} else
	407	gid = nonlocal_users_group.gr_gid;
	408	free(buffer);
48479fc7	409	}
1e78305d AK	410
	411	if (gid != -1) {
	412	int i;
	413	for (i = 0; i < *start; ++i)
	414	if ((*groupsp)[i] == gid)
	415	break;
	416	if (i >= *start) {
	417	if (start + 1 > size) {
	418	gid_t *newgroups;
	419	long int newsize = 2 * *size;
	420	if (limit > 0) {
	421	if (*size >= limit)
	422	return NSS_STATUS_SUCCESS;
	423	if (newsize > limit)
	424	newsize = limit;
	425	}
	426	newgroups = realloc(groupsp, size * sizeof((*groupsp)[0]));
	427	if (newgroups == NULL) {
	428	*errnop = ENOMEM;
	429	errno = old_errno;
	430	return NSS_STATUS_TRYAGAIN;
	431	}
	432	*groupsp = newgroups;
	433	*size = newsize;
	434	}
	435	(groupsp)[(start)++] = gid;
	436	}
48479fc7	437	}
f6903667	438
1e78305d AK	439	errno = old_errno;
	440
	441	if (is_local)
	442	return NSS_STATUS_SUCCESS;
	443
	444	int in = start, out = start, i;
	445
f6903667 AK	446	nip = nss_group_nonlocal_database();
	447	if (nip == NULL)
	448	return NSS_STATUS_UNAVAIL;
	449	if (fct_start == NULL)
	450	fct_start = __nss_lookup_function(nip, fct_name);
	451	fct.ptr = fct_start;
	452
	453	do {
	454	if (fct.ptr == NULL)
	455	status = NSS_STATUS_UNAVAIL;
	456	else
	457	status = DL_CALL_FCT(fct.l, (user, group, start, size, groupsp, limit, errnop));
	458	if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE)
	459	break;
	460	} while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
	461	if (status != NSS_STATUS_SUCCESS)
	462	return status;
	463
	464	for (; in < *start; ++in) {
	465	int nonlocal_errno = *errnop;
	466
	467	for (i = 0; i < out; ++i)
	468	if ((groupsp)[i] == (groupsp)[in])
	469	break;
	470	if (i < out)
	471	continue;
	472
1e78305d AK	473	/* Don't let users get into MAGIC_LOCAL_GROUPNAME from nonlocal reasons. */
	474	if (local_users_gid == (*groupsp)[in]) {
	475	syslog(LOG_WARNING, "nss_nonlocal: Nonlocal user %s removed from special local users group %s",
	476	user, MAGIC_LOCAL_GROUPNAME);
	477	continue;
	478	}
	479
f6903667 AK	480	status = check_nonlocal_gid(user, (*groupsp)[in], &nonlocal_errno);
f6903667 AK	481	if (status == NSS_STATUS_SUCCESS) {
1e78305d	482	(groupsp)[out++] = (groupsp)[in];
f6903667 AK	483	} else if (status != NSS_STATUS_NOTFOUND) {
	484	*start = out;
	485	*errnop = nonlocal_errno;
	486	return status;
	487	}
	488	}
	489
	490	*start = out;
	491	return NSS_STATUS_SUCCESS;
	492	}