[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_NONLOCAL_GROUPNAME "nss-nonlocal-users"
#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(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)
{
    static const char *fct_name = "getgrgid_r";
    static service_user *startp = NULL;
    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;
    struct group gbuf;
    int old_errno = errno;

    size_t buflen = sysconf(_SC_GETGR_R_SIZE_MAX);
    char *buf = malloc(buflen);
    if (buf == NULL) {
	*errnop = ENOMEM;
	errno = old_errno;
	return NSS_STATUS_TRYAGAIN;
    }

    if (fct_start == NULL &&
	__nss_group_lookup(&startp, fct_name, &fct_start) != 0) {
	free(buf);
	return NSS_STATUS_UNAVAIL;
    }
    nip = startp;
    fct.ptr = fct_start;
    do {
    morebuf:
	if (fct.l == _nss_nonlocal_getgrgid_r)
	    status = NSS_STATUS_NOTFOUND;
	else
	    status = DL_CALL_FCT(fct.l, (gid, &gbuf, buf, buflen, errnop));
	if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE) {
	    free(buf);
	    buflen *= 2;
	    buf = malloc(buflen);
	    if (buf == NULL) {
		*errnop = ENOMEM;
		errno = old_errno;
		return NSS_STATUS_TRYAGAIN;
	    }
	    goto morebuf;
	}
    } while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);

    if (status == NSS_STATUS_SUCCESS) {
	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;
    } else if (status != NSS_STATUS_TRYAGAIN) {
	status = NSS_STATUS_SUCCESS;
    }

    free(buf);
    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)
	status = check_nonlocal_gid(user, gid, errnop);
    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)
{
    static const char *fct_name = "getgrnam_r";
    static service_user *startp = NULL;
    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;
    size_t buflen;
    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;
    }

    if (fct_start == NULL &&
	__nss_group_lookup(&startp, fct_name, &fct_start) != 0) {
	free(*buffer);
	*buffer = NULL;
	return NSS_STATUS_UNAVAIL;
    }
    nip = startp;
    fct.ptr = fct_start;
    do {
    morebuf:
	if (fct.l == _nss_nonlocal_getgrnam_r)
	    status = NSS_STATUS_NOTFOUND;
	else
	    status = DL_CALL_FCT(fct.l, (name, grp, *buffer, buflen, errnop));
	if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE) {
	    free(*buffer);
	    buflen *= 2;
	    *buffer = malloc(buflen);
	    if (*buffer == NULL) {
		*errnop = ENOMEM;
		errno = old_errno;
		return NSS_STATUS_TRYAGAIN;
	    }
	    goto morebuf;
	}
    } while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);

    if (status != NSS_STATUS_SUCCESS) {
	free(*buffer);
	*buffer = NULL;
    }

    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 (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)
{
    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 (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;

    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)
{
    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 (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;

    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);
}

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;
    char *buffer;
    int old_errno;
    int in, out, i;

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

    old_errno = errno;

    status = get_local_group(MAGIC_LOCAL_GROUPNAME,
			     &local_users_group, &buffer, errnop);
    if (status == NSS_STATUS_SUCCESS) {
	local_users_gid = local_users_group.gr_gid;
	free(buffer);
    } else if (status == NSS_STATUS_TRYAGAIN) {
	return status;
    } else {
	syslog(LOG_WARNING, "nss_nonlocal: Group %s does not exist locally!",
	       MAGIC_LOCAL_GROUPNAME);
	local_users_gid = -1;
    }

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

    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, newsize * sizeof((*groupsp)[0]));
		if (newgroups == NULL) {
		    *errnop = ENOMEM;
		    errno = old_errno;
		    return NSS_STATUS_TRYAGAIN;
		}
		*groupsp = newgroups;
		*size = newsize;
	    }
	    (*groupsp)[(*start)++] = gid;
	}
    }

    if (is_local)
	return NSS_STATUS_SUCCESS;

    in = out = *start;

    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_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	*
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
48479fc7 TA	44	#define MAGIC_NONLOCAL_GROUPNAME "nss-nonlocal-users"
48479fc7 TA	45	#define MAGIC_LOCAL_GROUPNAME "nss-local-users"
f7293a54	46
f6903667	47
c1812233 AK	48	enum nss_status
	49	_nss_nonlocal_getgrnam_r(const char name, struct group grp,
	50	char buffer, size_t buflen, int errnop);
	51
	52	enum nss_status
	53	_nss_nonlocal_getgrgid_r(gid_t gid, struct group *grp,
	54	char buffer, size_t buflen, int errnop);
	55
	56
f6903667 AK	57	static service_user *
	58	nss_group_nonlocal_database(void)
	59	{
	60	static service_user *nip = NULL;
	61	if (nip == NULL)
	62	__nss_database_lookup("group_nonlocal", NULL, "", &nip);
48479fc7	63
f6903667 AK	64	return nip;
	65	}
	66
	67
f6903667 AK	68	enum nss_status
	69	check_nonlocal_gid(const char user, gid_t gid, int errnop)
	70	{
30fb3957 AK	71	static const char *fct_name = "getgrgid_r";
	72	static service_user *startp = NULL;
	73	static void *fct_start = NULL;
	74	enum nss_status status;
	75	service_user *nip;
	76	union {
	77	enum nss_status (l)(gid_t gid, struct group grp,
	78	char buffer, size_t buflen, int errnop);
	79	void *ptr;
	80	} fct;
f7293a54	81	struct group gbuf;
f7293a54	82	int old_errno = errno;
c1812233	83
8870ee9c	84	size_t buflen = sysconf(_SC_GETGR_R_SIZE_MAX);
f7293a54 AK	85	char *buf = malloc(buflen);
f7293a54 AK	86	if (buf == NULL) {
f6903667	87	*errnop = ENOMEM;
f7293a54	88	errno = old_errno;
f6903667 AK	89	return NSS_STATUS_TRYAGAIN;
f6903667 AK	90	}
30fb3957 AK	91
	92	if (fct_start == NULL &&
	93	__nss_group_lookup(&startp, fct_name, &fct_start) != 0) {
	94	free(buf);
	95	return NSS_STATUS_UNAVAIL;
	96	}
	97	nip = startp;
	98	fct.ptr = fct_start;
	99	do {
d905b369	100	morebuf:
c1812233 AK	101	if (fct.l == _nss_nonlocal_getgrgid_r)
	102	status = NSS_STATUS_NOTFOUND;
	103	else
	104	status = DL_CALL_FCT(fct.l, (gid, &gbuf, buf, buflen, errnop));
d905b369 AK	105	if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE) {
	106	free(buf);
	107	buflen *= 2;
	108	buf = malloc(buflen);
	109	if (buf == NULL) {
	110	*errnop = ENOMEM;
	111	errno = old_errno;
	112	return NSS_STATUS_TRYAGAIN;
	113	}
	114	goto morebuf;
	115	}
30fb3957 AK	116	} while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
	117
	118	if (status == NSS_STATUS_SUCCESS) {
f7293a54	119	syslog(LOG_WARNING, "nss_nonlocal: removing local group %u (%s) from non-local user %s\n", gbuf.gr_gid, gbuf.gr_name, user);
f6903667	120	status = NSS_STATUS_NOTFOUND;
30fb3957 AK	121	} else if (status != NSS_STATUS_TRYAGAIN) {
30fb3957 AK	122	status = NSS_STATUS_SUCCESS;
f6903667	123	}
30fb3957	124
f7293a54	125	free(buf);
f6903667 AK	126	return status;
	127	}
	128
cf338316 AK	129	enum nss_status
	130	check_nonlocal_group(const char user, struct group grp, int *errnop)
	131	{
a07a7616 AK	132	enum nss_status status = NSS_STATUS_SUCCESS;
	133	int old_errno = errno;
	134	char *end;
	135	unsigned long gid;
	136
	137	errno = 0;
	138	gid = strtoul(grp->gr_name, &end, 10);
	139	if (errno == 0 && *end == '\0' && (gid_t)gid == gid)
	140	status = check_nonlocal_gid(user, gid, errnop);
	141	errno = old_errno;
	142	if (status != NSS_STATUS_SUCCESS)
	143	return status;
	144
cf338316 AK	145	return check_nonlocal_gid(user, grp->gr_gid, errnop);
	146	}
	147
48479fc7	148	enum nss_status
8aa9014e	149	get_local_group(const char name, struct group grp, char *buffer, int errnop)
48479fc7	150	{
30fb3957 AK	151	static const char *fct_name = "getgrnam_r";
	152	static service_user *startp = NULL;
	153	static void *fct_start = NULL;
	154	enum nss_status status;
	155	service_user *nip;
	156	union {
	157	enum nss_status (l)(const char name, struct group *grp,
	158	char buffer, size_t buflen, int errnop);
	159	void *ptr;
	160	} fct;
8aa9014e	161	size_t buflen;
48479fc7	162	int old_errno = errno;
c1812233	163
8aa9014e AK	164	buflen = sysconf(_SC_GETGR_R_SIZE_MAX);
	165	*buffer = malloc(buflen);
	166	if (*buffer == NULL) {
48479fc7 TA	167	*errnop = ENOMEM;
	168	errno = old_errno;
	169	return NSS_STATUS_TRYAGAIN;
	170	}
1e78305d	171
30fb3957 AK	172	if (fct_start == NULL &&
30fb3957 AK	173	__nss_group_lookup(&startp, fct_name, &fct_start) != 0) {
8aa9014e AK	174	free(*buffer);
8aa9014e AK	175	*buffer = NULL;
30fb3957 AK	176	return NSS_STATUS_UNAVAIL;
	177	}
	178	nip = startp;
	179	fct.ptr = fct_start;
	180	do {
d905b369	181	morebuf:
c1812233 AK	182	if (fct.l == _nss_nonlocal_getgrnam_r)
	183	status = NSS_STATUS_NOTFOUND;
	184	else
8aa9014e	185	status = DL_CALL_FCT(fct.l, (name, grp, *buffer, buflen, errnop));
d905b369	186	if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE) {
8aa9014e AK	187	free(*buffer);
	188	buflen *= 2;
	189	*buffer = malloc(buflen);
	190	if (*buffer == NULL) {
d905b369 AK	191	*errnop = ENOMEM;
	192	errno = old_errno;
	193	return NSS_STATUS_TRYAGAIN;
	194	}
	195	goto morebuf;
	196	}
30fb3957 AK	197	} while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
30fb3957 AK	198
8aa9014e AK	199	if (status != NSS_STATUS_SUCCESS) {
	200	free(*buffer);
	201	*buffer = NULL;
48479fc7	202	}
30fb3957	203
48479fc7 TA	204	return status;
48479fc7 TA	205	}
f6903667 AK	206
	207	static service_user *grent_nip = NULL;
	208	static void *grent_fct_start;
	209	static union {
	210	enum nss_status (l)(struct group grp, char *buffer, size_t buflen,
	211	int *errnop);
	212	void *ptr;
	213	} grent_fct;
	214	static const char *grent_fct_name = "getgrent_r";
	215
	216	enum nss_status
	217	_nss_nonlocal_setgrent(int stayopen)
	218	{
	219	static const char *fct_name = "setgrent";
	220	static void *fct_start = NULL;
	221	enum nss_status status;
	222	service_user *nip;
	223	union {
	224	enum nss_status (*l)(int stayopen);
	225	void *ptr;
	226	} fct;
	227
	228	nip = nss_group_nonlocal_database();
	229	if (nip == NULL)
	230	return NSS_STATUS_UNAVAIL;
	231	if (fct_start == NULL)
	232	fct_start = __nss_lookup_function(nip, fct_name);
	233	fct.ptr = fct_start;
	234	do {
	235	if (fct.ptr == NULL)
	236	status = NSS_STATUS_UNAVAIL;
	237	else
	238	status = DL_CALL_FCT(fct.l, (stayopen));
	239	} while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
	240	if (status != NSS_STATUS_SUCCESS)
	241	return status;
	242
	243	grent_nip = nip;
	244	if (grent_fct_start == NULL)
	245	grent_fct_start = __nss_lookup_function(nip, grent_fct_name);
	246	grent_fct.ptr = grent_fct_start;
	247	return NSS_STATUS_SUCCESS;
	248	}
	249
	250	enum nss_status
	251	_nss_nonlocal_endgrent(void)
	252	{
	253	static const char *fct_name = "endgrent";
	254	static void *fct_start = NULL;
	255	enum nss_status status;
	256	service_user *nip;
	257	union {
	258	enum nss_status (*l)(void);
	259	void *ptr;
	260	} fct;
	261
	262	grent_nip = NULL;
	263
	264	nip = nss_group_nonlocal_database();
	265	if (nip == NULL)
	266	return NSS_STATUS_UNAVAIL;
	267	if (fct_start == NULL)
	268	fct_start = __nss_lookup_function(nip, fct_name);
	269	fct.ptr = fct_start;
270	do {
271	if (fct.ptr == NULL)
272	status = NSS_STATUS_UNAVAIL;
273	else
274	status = DL_CALL_FCT(fct.l, ());
275	} while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
276	return status;
277	}
278
279	enum nss_status
280	_nss_nonlocal_getgrent_r(struct group grp, char buffer, size_t buflen,
281	int *errnop)
282	{
283	enum nss_status status;
a360549e TA	284
a360549e TA	285	char *nonlocal_ignore = getenv(NONLOCAL_IGNORE_ENV);
c1812233	286	if (nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0')
a360549e TA	287	return NSS_STATUS_UNAVAIL;
a360549e TA	288
f6903667 AK	289	if (grent_nip == NULL) {
	290	status = _nss_nonlocal_setgrent(0);
	291	if (status != NSS_STATUS_SUCCESS)
	292	return status;
	293	}
	294	do {
	295	if (grent_fct.ptr == NULL)
	296	status = NSS_STATUS_UNAVAIL;
	297	else {
	298	int nonlocal_errno;
	299	do
	300	status = DL_CALL_FCT(grent_fct.l, (grp, buffer, buflen, errnop));
	301	while (status == NSS_STATUS_SUCCESS &&
cf338316	302	check_nonlocal_group("(unknown)", grp, &nonlocal_errno) != NSS_STATUS_SUCCESS);
f6903667 AK	303	}
	304	if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE)
	305	return status;
	306
	307	if (status == NSS_STATUS_SUCCESS)
	308	return NSS_STATUS_SUCCESS;
	309	} while (__nss_next(&grent_nip, grent_fct_name, &grent_fct.ptr, status, 0) == 0);
	310
	311	grent_nip = NULL;
	312	return NSS_STATUS_NOTFOUND;
	313	}
	314
	315
	316	enum nss_status
	317	_nss_nonlocal_getgrnam_r(const char name, struct group grp,
	318	char buffer, size_t buflen, int errnop)
	319	{
	320	static const char *fct_name = "getgrnam_r";
	321	static void *fct_start = NULL;
	322	enum nss_status status;
	323	service_user *nip;
	324	union {
	325	enum nss_status (l)(const char name, struct group *grp,
	326	char buffer, size_t buflen, int errnop);
	327	void *ptr;
	328	} fct;
	329
a360549e	330	char *nonlocal_ignore = getenv(NONLOCAL_IGNORE_ENV);
c1812233	331	if (nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0')
48479fc7 TA	332	return NSS_STATUS_UNAVAIL;
48479fc7 TA	333
f6903667 AK	334	nip = nss_group_nonlocal_database();
	335	if (nip == NULL)
	336	return NSS_STATUS_UNAVAIL;
	337	if (fct_start == NULL)
	338	fct_start = __nss_lookup_function(nip, fct_name);
	339	fct.ptr = fct_start;
	340	do {
	341	if (fct.ptr == NULL)
	342	status = NSS_STATUS_UNAVAIL;
	343	else
	344	status = DL_CALL_FCT(fct.l, (name, grp, buffer, buflen, errnop));
	345	if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE)
	346	break;
	347	} while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
	348	if (status != NSS_STATUS_SUCCESS)
	349	return status;
	350
22562df0 AK	351	if (strcmp(name, grp->gr_name) != 0) {
	352	syslog(LOG_ERR, "nss_nonlocal: discarding group %s from lookup for group %s\n", grp->gr_name, name);
	353	return NSS_STATUS_NOTFOUND;
	354	}
	355
cf338316	356	return check_nonlocal_group(name, grp, errnop);
f6903667 AK	357	}
	358
	359	enum nss_status
	360	_nss_nonlocal_getgrgid_r(gid_t gid, struct group *grp,
	361	char buffer, size_t buflen, int errnop)
	362	{
	363	static const char *fct_name = "getgrgid_r";
	364	static void *fct_start = NULL;
	365	enum nss_status status;
	366	service_user *nip;
	367	union {
	368	enum nss_status (l)(gid_t gid, struct group grp,
	369	char buffer, size_t buflen, int errnop);
	370	void *ptr;
	371	} fct;
	372
a360549e	373	char *nonlocal_ignore = getenv(NONLOCAL_IGNORE_ENV);
c1812233	374	if (nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0')
f6903667 AK	375	return NSS_STATUS_UNAVAIL;
	376
	377	nip = nss_group_nonlocal_database();
	378	if (nip == NULL)
	379	return NSS_STATUS_UNAVAIL;
	380	if (fct_start == NULL)
	381	fct_start = __nss_lookup_function(nip, fct_name);
	382	fct.ptr = fct_start;
	383	do {
	384	if (fct.ptr == NULL)
	385	status = NSS_STATUS_UNAVAIL;
	386	else
	387	status = DL_CALL_FCT(fct.l, (gid, grp, buffer, buflen, errnop));
	388	if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE)
	389	break;
	390	} while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
	391	if (status != NSS_STATUS_SUCCESS)
	392	return status;
	393
8027fdc4 AK	394	if (gid != grp->gr_gid) {
	395	syslog(LOG_ERR, "nss_nonlocal: discarding gid %d from lookup for gid %d\n", grp->gr_gid, gid);
	396	return NSS_STATUS_NOTFOUND;
	397	}
	398
cf338316	399	return check_nonlocal_group(grp->gr_name, grp, errnop);
f6903667 AK	400	}
	401
	402	enum nss_status
	403	_nss_nonlocal_initgroups_dyn(const char user, gid_t group, long int start,
	404	long int size, gid_t *groupsp, long int limit,
	405	int *errnop)
	406	{
	407	static const char *fct_name = "initgroups_dyn";
	408	static void *fct_start = NULL;
	409	enum nss_status status;
	410	service_user *nip;
	411	union {
	412	enum nss_status (l)(const char user, gid_t group, long int *start,
	413	long int size, gid_t *groupsp, long int limit,
	414	int *errnop);
	415	void *ptr;
	416	} fct;
1e78305d AK	417
	418	struct group local_users_group, nonlocal_users_group;
	419	gid_t local_users_gid, gid;
48479fc7	420	int is_local = 0;
1e78305d	421	char *buffer;
d7bf1d11 AK	422	int old_errno;
d7bf1d11 AK	423	int in, out, i;
48479fc7	424
1e78305d	425	/* Check that the user is a nonlocal user before adding any groups. */
48479fc7	426	status = check_nonlocal_user(user, errnop);
5879a696	427	if (status == NSS_STATUS_TRYAGAIN)
48479fc7	428	return status;
5879a696 AK	429	else if (status != NSS_STATUS_SUCCESS)
5879a696 AK	430	is_local = 1;
48479fc7	431
d7bf1d11	432	old_errno = errno;
1e78305d	433
48479fc7	434	status = get_local_group(MAGIC_LOCAL_GROUPNAME,
8aa9014e	435	&local_users_group, &buffer, errnop);
5879a696 AK	436	if (status == NSS_STATUS_SUCCESS) {
5879a696 AK	437	local_users_gid = local_users_group.gr_gid;
dc94c928	438	free(buffer);
8aa9014e	439	} else if (status == NSS_STATUS_TRYAGAIN) {
5879a696 AK	440	return status;
5879a696 AK	441	} else {
48479fc7 TA	442	syslog(LOG_WARNING, "nss_nonlocal: Group %s does not exist locally!",
48479fc7 TA	443	MAGIC_LOCAL_GROUPNAME);
1e78305d	444	local_users_gid = -1;
5879a696	445	}
1e78305d AK	446
	447	if (is_local) {
	448	gid = local_users_gid;
	449	} else {
1e78305d	450	status = get_local_group(MAGIC_NONLOCAL_GROUPNAME,
8aa9014e	451	&nonlocal_users_group, &buffer, errnop);
5879a696 AK	452	if (status == NSS_STATUS_SUCCESS) {
5879a696 AK	453	gid = nonlocal_users_group.gr_gid;
dc94c928	454	free(buffer);
8aa9014e	455	} else if (status == NSS_STATUS_TRYAGAIN) {
5879a696 AK	456	return status;
5879a696 AK	457	} else {
1e78305d AK	458	syslog(LOG_WARNING, "nss_nonlocal: Group %s does not exist locally!",
	459	MAGIC_NONLOCAL_GROUPNAME);
	460	gid = -1;
5879a696	461	}
48479fc7	462	}
1e78305d AK	463
	464	if (gid != -1) {
	465	int i;
	466	for (i = 0; i < *start; ++i)
	467	if ((*groupsp)[i] == gid)
	468	break;
	469	if (i >= *start) {
	470	if (start + 1 > size) {
	471	gid_t *newgroups;
	472	long int newsize = 2 * *size;
	473	if (limit > 0) {
	474	if (*size >= limit)
	475	return NSS_STATUS_SUCCESS;
	476	if (newsize > limit)
	477	newsize = limit;
	478	}
ad0399bd	479	newgroups = realloc(groupsp, newsize sizeof((*groupsp)[0]));
1e78305d AK	480	if (newgroups == NULL) {
	481	*errnop = ENOMEM;
	482	errno = old_errno;
	483	return NSS_STATUS_TRYAGAIN;
	484	}
	485	*groupsp = newgroups;
	486	*size = newsize;
	487	}
	488	(groupsp)[(start)++] = gid;
	489	}
48479fc7	490	}
f6903667	491
1e78305d AK	492	if (is_local)
	493	return NSS_STATUS_SUCCESS;
	494
d7bf1d11	495	in = out = *start;
1e78305d	496
f6903667 AK	497	nip = nss_group_nonlocal_database();
	498	if (nip == NULL)
	499	return NSS_STATUS_UNAVAIL;
	500	if (fct_start == NULL)
	501	fct_start = __nss_lookup_function(nip, fct_name);
	502	fct.ptr = fct_start;
	503
	504	do {
	505	if (fct.ptr == NULL)
	506	status = NSS_STATUS_UNAVAIL;
	507	else
	508	status = DL_CALL_FCT(fct.l, (user, group, start, size, groupsp, limit, errnop));
	509	if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE)
	510	break;
	511	} while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
	512	if (status != NSS_STATUS_SUCCESS)
	513	return status;
	514
	515	for (; in < *start; ++in) {
	516	int nonlocal_errno = *errnop;
	517
	518	for (i = 0; i < out; ++i)
	519	if ((groupsp)[i] == (groupsp)[in])
	520	break;
	521	if (i < out)
	522	continue;
	523
1e78305d AK	524	/* Don't let users get into MAGIC_LOCAL_GROUPNAME from nonlocal reasons. */
	525	if (local_users_gid == (*groupsp)[in]) {
	526	syslog(LOG_WARNING, "nss_nonlocal: Nonlocal user %s removed from special local users group %s",
	527	user, MAGIC_LOCAL_GROUPNAME);
	528	continue;
	529	}
	530
f6903667 AK	531	status = check_nonlocal_gid(user, (*groupsp)[in], &nonlocal_errno);
f6903667 AK	532	if (status == NSS_STATUS_SUCCESS) {
1e78305d	533	(groupsp)[out++] = (groupsp)[in];
5879a696	534	} else if (status == NSS_STATUS_TRYAGAIN) {
f6903667 AK	535	*start = out;
	536	*errnop = nonlocal_errno;
	537	return status;
	538	}
	539	}
	540
	541	*start = out;
	542	return NSS_STATUS_SUCCESS;
	543	}