[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
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_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;

    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_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;
    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
48479fc7	129	enum nss_status
8aa9014e	130	get_local_group(const char name, struct group grp, char *buffer, int errnop)
48479fc7	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;
8aa9014e	142	size_t buflen;
48479fc7	143	int old_errno = errno;
c1812233	144
8aa9014e AK	145	buflen = sysconf(_SC_GETGR_R_SIZE_MAX);
	146	*buffer = malloc(buflen);
	147	if (*buffer == NULL) {
48479fc7 TA	148	*errnop = ENOMEM;
	149	errno = old_errno;
	150	return NSS_STATUS_TRYAGAIN;
	151	}
1e78305d	152
30fb3957 AK	153	if (fct_start == NULL &&
30fb3957 AK	154	__nss_group_lookup(&startp, fct_name, &fct_start) != 0) {
8aa9014e AK	155	free(*buffer);
8aa9014e AK	156	*buffer = NULL;
30fb3957 AK	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
8aa9014e	166	status = DL_CALL_FCT(fct.l, (name, grp, *buffer, buflen, errnop));
d905b369	167	if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE) {
8aa9014e AK	168	free(*buffer);
	169	buflen *= 2;
	170	*buffer = malloc(buflen);
	171	if (*buffer == NULL) {
d905b369 AK	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
8aa9014e AK	180	if (status != NSS_STATUS_SUCCESS) {
	181	free(*buffer);
	182	*buffer = NULL;
48479fc7	183	}
30fb3957	184
48479fc7 TA	185	return status;
48479fc7 TA	186	}
f6903667 AK	187
	188	static service_user *grent_nip = NULL;
	189	static void *grent_fct_start;
	190	static union {
	191	enum nss_status (l)(struct group grp, char *buffer, size_t buflen,
	192	int *errnop);
	193	void *ptr;
	194	} grent_fct;
	195	static const char *grent_fct_name = "getgrent_r";
	196
	197	enum nss_status
	198	_nss_nonlocal_setgrent(int stayopen)
	199	{
	200	static const char *fct_name = "setgrent";
	201	static void *fct_start = NULL;
	202	enum nss_status status;
	203	service_user *nip;
	204	union {
	205	enum nss_status (*l)(int stayopen);
	206	void *ptr;
	207	} fct;
	208
	209	nip = nss_group_nonlocal_database();
	210	if (nip == NULL)
	211	return NSS_STATUS_UNAVAIL;
	212	if (fct_start == NULL)
	213	fct_start = __nss_lookup_function(nip, fct_name);
	214	fct.ptr = fct_start;
	215	do {
	216	if (fct.ptr == NULL)
	217	status = NSS_STATUS_UNAVAIL;
	218	else
	219	status = DL_CALL_FCT(fct.l, (stayopen));
	220	} while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
	221	if (status != NSS_STATUS_SUCCESS)
	222	return status;
	223
	224	grent_nip = nip;
	225	if (grent_fct_start == NULL)
	226	grent_fct_start = __nss_lookup_function(nip, grent_fct_name);
	227	grent_fct.ptr = grent_fct_start;
	228	return NSS_STATUS_SUCCESS;
	229	}
	230
	231	enum nss_status
	232	_nss_nonlocal_endgrent(void)
	233	{
	234	static const char *fct_name = "endgrent";
	235	static void *fct_start = NULL;
	236	enum nss_status status;
	237	service_user *nip;
	238	union {
	239	enum nss_status (*l)(void);
	240	void *ptr;
	241	} fct;
	242
	243	grent_nip = NULL;
	244
	245	nip = nss_group_nonlocal_database();
	246	if (nip == NULL)
	247	return NSS_STATUS_UNAVAIL;
	248	if (fct_start == NULL)
	249	fct_start = __nss_lookup_function(nip, fct_name);
	250	fct.ptr = fct_start;
251	do {
252	if (fct.ptr == NULL)
253	status = NSS_STATUS_UNAVAIL;
254	else
255	status = DL_CALL_FCT(fct.l, ());
256	} while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
257	return status;
258	}
259
260	enum nss_status
261	_nss_nonlocal_getgrent_r(struct group grp, char buffer, size_t buflen,
262	int *errnop)
263	{
264	enum nss_status status;
a360549e TA	265
a360549e TA	266	char *nonlocal_ignore = getenv(NONLOCAL_IGNORE_ENV);
c1812233	267	if (nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0')
a360549e TA	268	return NSS_STATUS_UNAVAIL;
a360549e TA	269
f6903667 AK	270	if (grent_nip == NULL) {
	271	status = _nss_nonlocal_setgrent(0);
	272	if (status != NSS_STATUS_SUCCESS)
	273	return status;
	274	}
	275	do {
	276	if (grent_fct.ptr == NULL)
	277	status = NSS_STATUS_UNAVAIL;
	278	else {
	279	int nonlocal_errno;
	280	do
	281	status = DL_CALL_FCT(grent_fct.l, (grp, buffer, buflen, errnop));
	282	while (status == NSS_STATUS_SUCCESS &&
	283	check_nonlocal_gid("(unknown)", grp->gr_gid, &nonlocal_errno) != NSS_STATUS_SUCCESS);
	284	}
	285	if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE)
	286	return status;
	287
	288	if (status == NSS_STATUS_SUCCESS)
	289	return NSS_STATUS_SUCCESS;
	290	} while (__nss_next(&grent_nip, grent_fct_name, &grent_fct.ptr, status, 0) == 0);
	291
	292	grent_nip = NULL;
	293	return NSS_STATUS_NOTFOUND;
	294	}
	295
	296
	297	enum nss_status
	298	_nss_nonlocal_getgrnam_r(const char name, struct group grp,
	299	char buffer, size_t buflen, int errnop)
	300	{
	301	static const char *fct_name = "getgrnam_r";
	302	static void *fct_start = NULL;
	303	enum nss_status status;
	304	service_user *nip;
	305	union {
	306	enum nss_status (l)(const char name, struct group *grp,
	307	char buffer, size_t buflen, int errnop);
	308	void *ptr;
	309	} fct;
	310
a360549e	311	char *nonlocal_ignore = getenv(NONLOCAL_IGNORE_ENV);
c1812233	312	if (nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0')
48479fc7 TA	313	return NSS_STATUS_UNAVAIL;
48479fc7 TA	314
f6903667 AK	315	nip = nss_group_nonlocal_database();
	316	if (nip == NULL)
	317	return NSS_STATUS_UNAVAIL;
	318	if (fct_start == NULL)
	319	fct_start = __nss_lookup_function(nip, fct_name);
	320	fct.ptr = fct_start;
	321	do {
	322	if (fct.ptr == NULL)
	323	status = NSS_STATUS_UNAVAIL;
	324	else
	325	status = DL_CALL_FCT(fct.l, (name, grp, buffer, buflen, errnop));
	326	if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE)
	327	break;
	328	} while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
	329	if (status != NSS_STATUS_SUCCESS)
	330	return status;
	331
22562df0 AK	332	if (strcmp(name, grp->gr_name) != 0) {
	333	syslog(LOG_ERR, "nss_nonlocal: discarding group %s from lookup for group %s\n", grp->gr_name, name);
	334	return NSS_STATUS_NOTFOUND;
	335	}
	336
f6903667 AK	337	return check_nonlocal_gid(name, grp->gr_gid, errnop);
	338	}
	339
	340	enum nss_status
	341	_nss_nonlocal_getgrgid_r(gid_t gid, struct group *grp,
	342	char buffer, size_t buflen, int errnop)
	343	{
	344	static const char *fct_name = "getgrgid_r";
	345	static void *fct_start = NULL;
	346	enum nss_status status;
	347	service_user *nip;
	348	union {
	349	enum nss_status (l)(gid_t gid, struct group grp,
	350	char buffer, size_t buflen, int errnop);
	351	void *ptr;
	352	} fct;
	353
a360549e	354	char *nonlocal_ignore = getenv(NONLOCAL_IGNORE_ENV);
c1812233	355	if (nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0')
f6903667 AK	356	return NSS_STATUS_UNAVAIL;
	357
	358	nip = nss_group_nonlocal_database();
	359	if (nip == NULL)
	360	return NSS_STATUS_UNAVAIL;
	361	if (fct_start == NULL)
	362	fct_start = __nss_lookup_function(nip, fct_name);
	363	fct.ptr = fct_start;
	364	do {
	365	if (fct.ptr == NULL)
	366	status = NSS_STATUS_UNAVAIL;
	367	else
	368	status = DL_CALL_FCT(fct.l, (gid, grp, buffer, buflen, errnop));
	369	if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE)
	370	break;
	371	} while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
	372	if (status != NSS_STATUS_SUCCESS)
	373	return status;
	374
	375	return check_nonlocal_gid(grp->gr_name, grp->gr_gid, errnop);
	376	}
	377
	378	enum nss_status
	379	_nss_nonlocal_initgroups_dyn(const char user, gid_t group, long int start,
	380	long int size, gid_t *groupsp, long int limit,
	381	int *errnop)
	382	{
	383	static const char *fct_name = "initgroups_dyn";
	384	static void *fct_start = NULL;
	385	enum nss_status status;
	386	service_user *nip;
	387	union {
	388	enum nss_status (l)(const char user, gid_t group, long int *start,
	389	long int size, gid_t *groupsp, long int limit,
	390	int *errnop);
	391	void *ptr;
	392	} fct;
1e78305d AK	393
	394	struct group local_users_group, nonlocal_users_group;
	395	gid_t local_users_gid, gid;
48479fc7	396	int is_local = 0;
1e78305d	397	char *buffer;
d7bf1d11 AK	398	int old_errno;
d7bf1d11 AK	399	int in, out, i;
48479fc7	400
1e78305d	401	/* Check that the user is a nonlocal user before adding any groups. */
48479fc7	402	status = check_nonlocal_user(user, errnop);
5879a696	403	if (status == NSS_STATUS_TRYAGAIN)
48479fc7	404	return status;
5879a696 AK	405	else if (status != NSS_STATUS_SUCCESS)
5879a696 AK	406	is_local = 1;
48479fc7	407
d7bf1d11	408	old_errno = errno;
1e78305d	409
48479fc7	410	status = get_local_group(MAGIC_LOCAL_GROUPNAME,
8aa9014e	411	&local_users_group, &buffer, errnop);
5879a696 AK	412	if (status == NSS_STATUS_SUCCESS) {
5879a696 AK	413	local_users_gid = local_users_group.gr_gid;
dc94c928	414	free(buffer);
8aa9014e	415	} else if (status == NSS_STATUS_TRYAGAIN) {
5879a696 AK	416	return status;
5879a696 AK	417	} else {
48479fc7 TA	418	syslog(LOG_WARNING, "nss_nonlocal: Group %s does not exist locally!",
48479fc7 TA	419	MAGIC_LOCAL_GROUPNAME);
1e78305d	420	local_users_gid = -1;
5879a696	421	}
1e78305d AK	422
	423	if (is_local) {
	424	gid = local_users_gid;
	425	} else {
1e78305d	426	status = get_local_group(MAGIC_NONLOCAL_GROUPNAME,
8aa9014e	427	&nonlocal_users_group, &buffer, errnop);
5879a696 AK	428	if (status == NSS_STATUS_SUCCESS) {
5879a696 AK	429	gid = nonlocal_users_group.gr_gid;
dc94c928	430	free(buffer);
8aa9014e	431	} else if (status == NSS_STATUS_TRYAGAIN) {
5879a696 AK	432	return status;
5879a696 AK	433	} else {
1e78305d AK	434	syslog(LOG_WARNING, "nss_nonlocal: Group %s does not exist locally!",
	435	MAGIC_NONLOCAL_GROUPNAME);
	436	gid = -1;
5879a696	437	}
48479fc7	438	}
1e78305d AK	439
	440	if (gid != -1) {
	441	int i;
	442	for (i = 0; i < *start; ++i)
	443	if ((*groupsp)[i] == gid)
	444	break;
	445	if (i >= *start) {
	446	if (start + 1 > size) {
	447	gid_t *newgroups;
	448	long int newsize = 2 * *size;
	449	if (limit > 0) {
	450	if (*size >= limit)
	451	return NSS_STATUS_SUCCESS;
	452	if (newsize > limit)
	453	newsize = limit;
	454	}
ad0399bd	455	newgroups = realloc(groupsp, newsize sizeof((*groupsp)[0]));
1e78305d AK	456	if (newgroups == NULL) {
	457	*errnop = ENOMEM;
	458	errno = old_errno;
	459	return NSS_STATUS_TRYAGAIN;
	460	}
	461	*groupsp = newgroups;
	462	*size = newsize;
	463	}
	464	(groupsp)[(start)++] = gid;
	465	}
48479fc7	466	}
f6903667	467
1e78305d AK	468	if (is_local)
	469	return NSS_STATUS_SUCCESS;
	470
d7bf1d11	471	in = out = *start;
1e78305d	472
f6903667 AK	473	nip = nss_group_nonlocal_database();
	474	if (nip == NULL)
	475	return NSS_STATUS_UNAVAIL;
	476	if (fct_start == NULL)
	477	fct_start = __nss_lookup_function(nip, fct_name);
	478	fct.ptr = fct_start;
	479
	480	do {
	481	if (fct.ptr == NULL)
	482	status = NSS_STATUS_UNAVAIL;
	483	else
	484	status = DL_CALL_FCT(fct.l, (user, group, start, size, groupsp, limit, errnop));
	485	if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE)
	486	break;
	487	} while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
	488	if (status != NSS_STATUS_SUCCESS)
	489	return status;
	490
	491	for (; in < *start; ++in) {
	492	int nonlocal_errno = *errnop;
	493
	494	for (i = 0; i < out; ++i)
	495	if ((groupsp)[i] == (groupsp)[in])
	496	break;
	497	if (i < out)
	498	continue;
	499
1e78305d AK	500	/* Don't let users get into MAGIC_LOCAL_GROUPNAME from nonlocal reasons. */
	501	if (local_users_gid == (*groupsp)[in]) {
	502	syslog(LOG_WARNING, "nss_nonlocal: Nonlocal user %s removed from special local users group %s",
	503	user, MAGIC_LOCAL_GROUPNAME);
	504	continue;
	505	}
	506
f6903667 AK	507	status = check_nonlocal_gid(user, (*groupsp)[in], &nonlocal_errno);
f6903667 AK	508	if (status == NSS_STATUS_SUCCESS) {
1e78305d	509	(groupsp)[out++] = (groupsp)[in];
5879a696	510	} else if (status == NSS_STATUS_TRYAGAIN) {
f6903667 AK	511	*start = out;
	512	*errnop = nonlocal_errno;
	513	return status;
	514	}
	515	}
	516
	517	*start = out;
	518	return NSS_STATUS_SUCCESS;
	519	}