[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;

    int 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
get_local_group(const char *name, struct group *grp, char *buffer, size_t buflen, 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;
    struct group gbuf;
    int n;
    int old_errno = errno;

    int len = sysconf(_SC_GETGR_R_SIZE_MAX);
    char *buf = malloc(len);
    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_getgrnam_r)
	    status = NSS_STATUS_NOTFOUND;
	else
	    status = DL_CALL_FCT(fct.l, (name, &gbuf, buf, len, errnop));
	if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE) {
	    free(buf);
	    len *= 2;
	    buf = malloc(len);
	    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)
	goto get_local_group_done;

    n = snprintf(buffer, buflen, "%s", gbuf.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", gbuf.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 = gbuf.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);
    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_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 (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 (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_TRYAGAIN)
	return status;
    else if (status != NSS_STATUS_SUCCESS)
	is_local = 1;

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

    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_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 AK	83
c1812233 AK	84	int 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
48479fc7 TA	129	enum nss_status
	130	get_local_group(const char name, struct group grp, char buffer, size_t buflen, int errnop)
	131	{
30fb3957 AK	132	static const char *fct_name = "getgrnam_r";
	133	static service_user *startp = NULL;
	134	static void *fct_start = NULL;
	135	enum nss_status status;
	136	service_user *nip;
	137	union {
	138	enum nss_status (l)(const char name, struct group *grp,
	139	char buffer, size_t buflen, int errnop);
	140	void *ptr;
	141	} fct;
48479fc7	142	struct group gbuf;
30fb3957	143	int n;
48479fc7	144	int old_errno = errno;
c1812233 AK	145
c1812233 AK	146	int len = sysconf(_SC_GETGR_R_SIZE_MAX);
48479fc7 TA	147	char *buf = malloc(len);
	148	if (buf == NULL) {
	149	*errnop = ENOMEM;
	150	errno = old_errno;
	151	return NSS_STATUS_TRYAGAIN;
	152	}
1e78305d	153
30fb3957 AK	154	if (fct_start == NULL &&
	155	__nss_group_lookup(&startp, fct_name, &fct_start) != 0) {
	156	free(buf);
	157	return NSS_STATUS_UNAVAIL;
	158	}
	159	nip = startp;
	160	fct.ptr = fct_start;
	161	do {
d905b369	162	morebuf:
c1812233 AK	163	if (fct.l == _nss_nonlocal_getgrnam_r)
	164	status = NSS_STATUS_NOTFOUND;
	165	else
c5e25ab7	166	status = DL_CALL_FCT(fct.l, (name, &gbuf, buf, len, errnop));
d905b369 AK	167	if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE) {
	168	free(buf);
	169	len *= 2;
	170	buf = malloc(len);
	171	if (buf == NULL) {
	172	*errnop = ENOMEM;
	173	errno = old_errno;
	174	return NSS_STATUS_TRYAGAIN;
	175	}
	176	goto morebuf;
	177	}
30fb3957 AK	178	} while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
30fb3957 AK	179
f943c4ed AK	180	if (status != NSS_STATUS_SUCCESS)
	181	goto get_local_group_done;
	182
	183	n = snprintf(buffer, buflen, "%s", gbuf.gr_name);
	184	if (n < 0 \|\| n >= buflen) {
	185	*errnop = ERANGE;
	186	status = NSS_STATUS_TRYAGAIN;
	187	goto get_local_group_done;
	188	}
	189	grp->gr_name = buffer;
	190	buffer += n;
	191	buflen -= n;
	192
	193	n = snprintf(buffer, buflen, "%s", gbuf.gr_passwd);
	194	if (n < 0 \|\| n >= buflen) {
	195	*errnop = ERANGE;
	196	status = NSS_STATUS_TRYAGAIN;
	197	goto get_local_group_done;
	198	}
	199	grp->gr_passwd = buffer;
	200	buffer += n;
	201	buflen -= n;
	202
	203	grp->gr_gid = gbuf.gr_gid;
	204
	205	if (buflen < sizeof(void *)) {
	206	*errnop = ERANGE;
	207	status = NSS_STATUS_TRYAGAIN;
	208	goto get_local_group_done;
48479fc7	209	}
f943c4ed AK	210	(void *)buffer = NULL;
	211	buffer += sizeof(void *);
	212	buflen -= sizeof(void *);
30fb3957	213
1e78305d	214	get_local_group_done:
48479fc7	215	free(buf);
48479fc7 TA	216	return status;
48479fc7 TA	217	}
f6903667 AK	218
	219	static service_user *grent_nip = NULL;
	220	static void *grent_fct_start;
	221	static union {
	222	enum nss_status (l)(struct group grp, char *buffer, size_t buflen,
	223	int *errnop);
	224	void *ptr;
	225	} grent_fct;
	226	static const char *grent_fct_name = "getgrent_r";
	227
	228	enum nss_status
	229	_nss_nonlocal_setgrent(int stayopen)
	230	{
	231	static const char *fct_name = "setgrent";
	232	static void *fct_start = NULL;
	233	enum nss_status status;
	234	service_user *nip;
	235	union {
	236	enum nss_status (*l)(int stayopen);
	237	void *ptr;
	238	} fct;
	239
	240	nip = nss_group_nonlocal_database();
	241	if (nip == NULL)
	242	return NSS_STATUS_UNAVAIL;
	243	if (fct_start == NULL)
	244	fct_start = __nss_lookup_function(nip, fct_name);
	245	fct.ptr = fct_start;
	246	do {
	247	if (fct.ptr == NULL)
	248	status = NSS_STATUS_UNAVAIL;
	249	else
	250	status = DL_CALL_FCT(fct.l, (stayopen));
	251	} while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
	252	if (status != NSS_STATUS_SUCCESS)
	253	return status;
	254
	255	grent_nip = nip;
	256	if (grent_fct_start == NULL)
	257	grent_fct_start = __nss_lookup_function(nip, grent_fct_name);
	258	grent_fct.ptr = grent_fct_start;
	259	return NSS_STATUS_SUCCESS;
	260	}
	261
	262	enum nss_status
	263	_nss_nonlocal_endgrent(void)
	264	{
	265	static const char *fct_name = "endgrent";
	266	static void *fct_start = NULL;
	267	enum nss_status status;
	268	service_user *nip;
	269	union {
	270	enum nss_status (*l)(void);
	271	void *ptr;
	272	} fct;
	273
	274	grent_nip = NULL;
	275
	276	nip = nss_group_nonlocal_database();
	277	if (nip == NULL)
	278	return NSS_STATUS_UNAVAIL;
	279	if (fct_start == NULL)
	280	fct_start = __nss_lookup_function(nip, fct_name);
	281	fct.ptr = fct_start;
282	do {
283	if (fct.ptr == NULL)
284	status = NSS_STATUS_UNAVAIL;
285	else
286	status = DL_CALL_FCT(fct.l, ());
287	} while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
288	return status;
289	}
290
291	enum nss_status
292	_nss_nonlocal_getgrent_r(struct group grp, char buffer, size_t buflen,
293	int *errnop)
294	{
295	enum nss_status status;
a360549e TA	296
a360549e TA	297	char *nonlocal_ignore = getenv(NONLOCAL_IGNORE_ENV);
c1812233	298	if (nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0')
a360549e TA	299	return NSS_STATUS_UNAVAIL;
a360549e TA	300
f6903667 AK	301	if (grent_nip == NULL) {
	302	status = _nss_nonlocal_setgrent(0);
	303	if (status != NSS_STATUS_SUCCESS)
	304	return status;
	305	}
	306	do {
	307	if (grent_fct.ptr == NULL)
	308	status = NSS_STATUS_UNAVAIL;
	309	else {
	310	int nonlocal_errno;
	311	do
	312	status = DL_CALL_FCT(grent_fct.l, (grp, buffer, buflen, errnop));
	313	while (status == NSS_STATUS_SUCCESS &&
	314	check_nonlocal_gid("(unknown)", grp->gr_gid, &nonlocal_errno) != NSS_STATUS_SUCCESS);
	315	}
	316	if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE)
	317	return status;
	318
	319	if (status == NSS_STATUS_SUCCESS)
	320	return NSS_STATUS_SUCCESS;
	321	} while (__nss_next(&grent_nip, grent_fct_name, &grent_fct.ptr, status, 0) == 0);
	322
	323	grent_nip = NULL;
	324	return NSS_STATUS_NOTFOUND;
	325	}
	326
	327
	328	enum nss_status
	329	_nss_nonlocal_getgrnam_r(const char name, struct group grp,
	330	char buffer, size_t buflen, int errnop)
	331	{
	332	static const char *fct_name = "getgrnam_r";
	333	static void *fct_start = NULL;
	334	enum nss_status status;
	335	service_user *nip;
	336	union {
	337	enum nss_status (l)(const char name, struct group *grp,
	338	char buffer, size_t buflen, int errnop);
	339	void *ptr;
	340	} fct;
	341
a360549e	342	char *nonlocal_ignore = getenv(NONLOCAL_IGNORE_ENV);
c1812233	343	if (nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0')
48479fc7 TA	344	return NSS_STATUS_UNAVAIL;
48479fc7 TA	345
f6903667 AK	346	nip = nss_group_nonlocal_database();
	347	if (nip == NULL)
	348	return NSS_STATUS_UNAVAIL;
	349	if (fct_start == NULL)
	350	fct_start = __nss_lookup_function(nip, fct_name);
	351	fct.ptr = fct_start;
	352	do {
	353	if (fct.ptr == NULL)
	354	status = NSS_STATUS_UNAVAIL;
	355	else
	356	status = DL_CALL_FCT(fct.l, (name, grp, buffer, buflen, errnop));
	357	if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE)
	358	break;
	359	} while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
	360	if (status != NSS_STATUS_SUCCESS)
	361	return status;
	362
	363	return check_nonlocal_gid(name, grp->gr_gid, errnop);
	364	}
	365
	366	enum nss_status
	367	_nss_nonlocal_getgrgid_r(gid_t gid, struct group *grp,
	368	char buffer, size_t buflen, int errnop)
	369	{
	370	static const char *fct_name = "getgrgid_r";
	371	static void *fct_start = NULL;
	372	enum nss_status status;
	373	service_user *nip;
	374	union {
	375	enum nss_status (l)(gid_t gid, struct group grp,
	376	char buffer, size_t buflen, int errnop);
	377	void *ptr;
	378	} fct;
	379
a360549e	380	char *nonlocal_ignore = getenv(NONLOCAL_IGNORE_ENV);
c1812233	381	if (nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0')
f6903667 AK	382	return NSS_STATUS_UNAVAIL;
	383
	384	nip = nss_group_nonlocal_database();
	385	if (nip == NULL)
	386	return NSS_STATUS_UNAVAIL;
	387	if (fct_start == NULL)
	388	fct_start = __nss_lookup_function(nip, fct_name);
	389	fct.ptr = fct_start;
	390	do {
	391	if (fct.ptr == NULL)
	392	status = NSS_STATUS_UNAVAIL;
	393	else
	394	status = DL_CALL_FCT(fct.l, (gid, grp, buffer, buflen, errnop));
	395	if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE)
	396	break;
	397	} while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
	398	if (status != NSS_STATUS_SUCCESS)
	399	return status;
	400
	401	return check_nonlocal_gid(grp->gr_name, grp->gr_gid, errnop);
	402	}
	403
	404	enum nss_status
	405	_nss_nonlocal_initgroups_dyn(const char user, gid_t group, long int start,
	406	long int size, gid_t *groupsp, long int limit,
	407	int *errnop)
	408	{
	409	static const char *fct_name = "initgroups_dyn";
	410	static void *fct_start = NULL;
	411	enum nss_status status;
	412	service_user *nip;
	413	union {
	414	enum nss_status (l)(const char user, gid_t group, long int *start,
	415	long int size, gid_t *groupsp, long int limit,
	416	int *errnop);
	417	void *ptr;
	418	} fct;
1e78305d AK	419
	420	struct group local_users_group, nonlocal_users_group;
	421	gid_t local_users_gid, gid;
48479fc7	422	int is_local = 0;
1e78305d AK	423	int buflen;
1e78305d AK	424	char *buffer;
48479fc7	425
1e78305d	426	/* Check that the user is a nonlocal user before adding any groups. */
48479fc7	427	status = check_nonlocal_user(user, errnop);
5879a696	428	if (status == NSS_STATUS_TRYAGAIN)
48479fc7	429	return status;
5879a696 AK	430	else if (status != NSS_STATUS_SUCCESS)
5879a696 AK	431	is_local = 1;
48479fc7	432
1e78305d AK	433	int old_errno = errno;
	434
	435	buflen = sysconf(_SC_GETGR_R_SIZE_MAX);
	436	buffer = malloc(buflen);
48479fc7 TA	437	if (buffer == NULL) {
48479fc7 TA	438	*errnop = ENOMEM;
1e78305d	439	errno = old_errno;
48479fc7 TA	440	return NSS_STATUS_TRYAGAIN;
48479fc7 TA	441	}
48479fc7 TA	442	status = get_local_group(MAGIC_LOCAL_GROUPNAME,
48479fc7 TA	443	&local_users_group, buffer, buflen, errnop);
5879a696 AK	444	if (status == NSS_STATUS_SUCCESS) {
	445	local_users_gid = local_users_group.gr_gid;
	446	} else if (status == NSS_STATUS_TRYAGAIN) {
dc94c928	447	free(buffer);
5879a696 AK	448	return status;
5879a696 AK	449	} else {
48479fc7 TA	450	syslog(LOG_WARNING, "nss_nonlocal: Group %s does not exist locally!",
48479fc7 TA	451	MAGIC_LOCAL_GROUPNAME);
1e78305d	452	local_users_gid = -1;
5879a696	453	}
1e78305d AK	454	free(buffer);
	455
	456	if (is_local) {
	457	gid = local_users_gid;
	458	} else {
	459	buflen = sysconf(_SC_GETGR_R_SIZE_MAX);
	460	buffer = malloc(buflen);
	461	if (buffer == NULL) {
	462	*errnop = ENOMEM;
	463	errno = old_errno;
	464	return NSS_STATUS_TRYAGAIN;
48479fc7	465	}
1e78305d AK	466	status = get_local_group(MAGIC_NONLOCAL_GROUPNAME,
1e78305d AK	467	&nonlocal_users_group, buffer, buflen, errnop);
5879a696 AK	468	if (status == NSS_STATUS_SUCCESS) {
	469	gid = nonlocal_users_group.gr_gid;
	470	} else if (status == NSS_STATUS_TRYAGAIN) {
dc94c928	471	free(buffer);
5879a696 AK	472	return status;
5879a696 AK	473	} else {
1e78305d AK	474	syslog(LOG_WARNING, "nss_nonlocal: Group %s does not exist locally!",
	475	MAGIC_NONLOCAL_GROUPNAME);
	476	gid = -1;
5879a696	477	}
1e78305d	478	free(buffer);
48479fc7	479	}
1e78305d AK	480
	481	if (gid != -1) {
	482	int i;
	483	for (i = 0; i < *start; ++i)
	484	if ((*groupsp)[i] == gid)
	485	break;
	486	if (i >= *start) {
	487	if (start + 1 > size) {
	488	gid_t *newgroups;
	489	long int newsize = 2 * *size;
	490	if (limit > 0) {
	491	if (*size >= limit)
	492	return NSS_STATUS_SUCCESS;
	493	if (newsize > limit)
	494	newsize = limit;
	495	}
ad0399bd	496	newgroups = realloc(groupsp, newsize sizeof((*groupsp)[0]));
1e78305d AK	497	if (newgroups == NULL) {
	498	*errnop = ENOMEM;
	499	errno = old_errno;
	500	return NSS_STATUS_TRYAGAIN;
	501	}
	502	*groupsp = newgroups;
	503	*size = newsize;
	504	}
	505	(groupsp)[(start)++] = gid;
	506	}
48479fc7	507	}
f6903667	508
1e78305d AK	509	if (is_local)
	510	return NSS_STATUS_SUCCESS;
	511
	512	int in = start, out = start, i;
	513
f6903667 AK	514	nip = nss_group_nonlocal_database();
	515	if (nip == NULL)
	516	return NSS_STATUS_UNAVAIL;
	517	if (fct_start == NULL)
	518	fct_start = __nss_lookup_function(nip, fct_name);
	519	fct.ptr = fct_start;
	520
	521	do {
	522	if (fct.ptr == NULL)
	523	status = NSS_STATUS_UNAVAIL;
	524	else
	525	status = DL_CALL_FCT(fct.l, (user, group, start, size, groupsp, limit, errnop));
	526	if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE)
	527	break;
	528	} while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
	529	if (status != NSS_STATUS_SUCCESS)
	530	return status;
	531
	532	for (; in < *start; ++in) {
	533	int nonlocal_errno = *errnop;
	534
	535	for (i = 0; i < out; ++i)
	536	if ((groupsp)[i] == (groupsp)[in])
	537	break;
	538	if (i < out)
	539	continue;
	540
1e78305d AK	541	/* Don't let users get into MAGIC_LOCAL_GROUPNAME from nonlocal reasons. */
	542	if (local_users_gid == (*groupsp)[in]) {
	543	syslog(LOG_WARNING, "nss_nonlocal: Nonlocal user %s removed from special local users group %s",
	544	user, MAGIC_LOCAL_GROUPNAME);
	545	continue;
	546	}
	547
f6903667 AK	548	status = check_nonlocal_gid(user, (*groupsp)[in], &nonlocal_errno);
f6903667 AK	549	if (status == NSS_STATUS_SUCCESS) {
1e78305d	550	(groupsp)[out++] = (groupsp)[in];
5879a696	551	} else if (status == NSS_STATUS_TRYAGAIN) {
f6903667 AK	552	*start = out;
	553	*errnop = nonlocal_errno;
	554	return status;
	555	}
	556	}
	557
	558	*start = out;
	559	return NSS_STATUS_SUCCESS;
	560	}