glibc/nis/nss_nis/nis-initgroups.c

336 lines
7.8 KiB
C

/* Copyright (C) 1998-2000, 2002, 2003, 2004 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Thorsten Kukuk <kukuk@suse.de>, 1998.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <alloca.h>
#include <ctype.h>
#include <errno.h>
#include <grp.h>
#include <nss.h>
#include <pwd.h>
#include <string.h>
#include <unistd.h>
#include <rpcsvc/yp.h>
#include <rpcsvc/ypclnt.h>
#include <sys/param.h>
#include "nss-nis.h"
/* Get the declaration of the parser function. */
#define ENTNAME grent
#define STRUCTURE group
#define EXTERN_PARSER
#include <nss/nss_files/files-parse.c>
struct response_t
{
struct response_t *next;
char val[0];
};
struct intern_t
{
struct response_t *start;
struct response_t *next;
};
typedef struct intern_t intern_t;
static int
saveit (int instatus, char *inkey, int inkeylen, char *inval,
int invallen, char *indata)
{
intern_t *intern = (intern_t *) indata;
if (instatus != YP_TRUE)
return 1;
if (inkey && inkeylen > 0 && inval && invallen > 0)
{
struct response_t *newp = malloc (sizeof (struct response_t)
+ invallen + 1);
if (newp == NULL)
return 1; /* We have no error code for out of memory */
if (intern->start == NULL)
intern->start = newp;
else
intern->next->next = newp;
intern->next = newp;
newp->next = NULL;
*((char *) mempcpy (newp->val, inval, invallen)) = '\0';
}
return 0;
}
static enum nss_status
internal_setgrent (char *domainname, intern_t *intern)
{
struct ypall_callback ypcb;
enum nss_status status;
intern->start = NULL;
ypcb.foreach = saveit;
ypcb.data = (char *) intern;
status = yperr2nss (yp_all (domainname, "group.byname", &ypcb));
intern->next = intern->start;
return status;
}
static enum nss_status
internal_getgrent_r (struct group *grp, char *buffer, size_t buflen,
int *errnop, intern_t *intern)
{
struct parser_data *data = (void *) buffer;
int parse_res;
char *p;
if (intern->start == NULL)
return NSS_STATUS_NOTFOUND;
/* Get the next entry until we found a correct one. */
do
{
if (intern->next == NULL)
return NSS_STATUS_NOTFOUND;
p = strncpy (buffer, intern->next->val, buflen);
while (isspace (*p))
++p;
parse_res = _nss_files_parse_grent (p, grp, data, buflen, errnop);
if (parse_res == -1)
return NSS_STATUS_TRYAGAIN;
intern->next = intern->next->next;
}
while (!parse_res);
return NSS_STATUS_SUCCESS;
}
static int
get_uid (const char *user, uid_t *uidp)
{
size_t buflen = sysconf (_SC_GETPW_R_SIZE_MAX);
char *buf = (char *) alloca (buflen);
while (1)
{
struct passwd result;
struct passwd *resp;
int r = getpwnam_r (user, &result, buf, buflen, &resp);
if (r == 0 && resp != NULL)
{
*uidp = resp->pw_uid;
return 0;
}
if (r != ERANGE)
break;
extend_alloca (buf, buflen, 2 * buflen);
}
return 1;
}
static enum nss_status
initgroups_netid (uid_t uid, gid_t group, long int *start, long int *size,
gid_t **groupsp, long int limit, int *errnop,
const char *domainname)
{
/* Prepare the key. The form is "unix.UID@DOMAIN" with the UID and
DOMAIN field filled in appropriately. */
char key[sizeof ("unix.@") + sizeof (uid_t) * 3 + strlen (domainname)];
ssize_t keylen = snprintf (key, sizeof (key), "unix.%lu@%s",
(unsigned long int) uid, domainname);
enum nss_status retval;
char *result;
int reslen;
retval = yperr2nss (yp_match (domainname, "netid.byname", key, keylen,
&result, &reslen));
if (retval != NSS_STATUS_SUCCESS)
return retval;
/* Parse the result: following the colon is a comma separated list of
group IDs. */
char *cp = strchr (result, ':');
if (cp == NULL)
{
errout:
free (result);
return NSS_STATUS_NOTFOUND;
}
/* Skip the colon. */
++cp;
gid_t *groups = *groupsp;
while (*cp != '\0')
{
char *endp;
unsigned long int gid = strtoul (cp, &endp, 0);
if (cp == endp)
goto errout;
if (*endp == ',')
++endp;
else if (*endp != '\0')
goto errout;
cp = endp;
if (gid == group)
/* We do not need this group again. */
continue;
/* Insert this group. */
if (*start == *size)
{
/* Need a bigger buffer. */
gid_t *newgroups;
long int newsize;
if (limit > 0 && *size == limit)
/* We reached the maximum. */
break;
if (limit <= 0)
newsize = 2 * *size;
else
newsize = MIN (limit, 2 * *size);
newgroups = realloc (groups, newsize * sizeof (*groups));
if (newgroups == NULL)
goto errout;
*groupsp = groups = newgroups;
*size = newsize;
}
groups[*start] = gid;
*start += 1;
}
free (result);
return NSS_STATUS_SUCCESS;
}
enum nss_status
_nss_nis_initgroups_dyn (const char *user, gid_t group, long int *start,
long int *size, gid_t **groupsp, long int limit,
int *errnop)
{
/* We always need the domain name. */
char *domainname;
if (yp_get_default_domain (&domainname))
return NSS_STATUS_UNAVAIL;
/* Check whether we are supposed to use the netid.byname map. */
if (_nis_default_nss () & NSS_FLAG_NETID_AUTHORITATIVE)
{
/* We need the user ID. */
uid_t uid;
if (get_uid (user, &uid) == 0
&& initgroups_netid (uid, group, start, size, groupsp, limit,
errnop, domainname) == NSS_STATUS_SUCCESS)
return NSS_STATUS_SUCCESS;
}
struct group grpbuf, *g;
size_t buflen = sysconf (_SC_GETPW_R_SIZE_MAX);
char *tmpbuf;
enum nss_status status;
intern_t intern = { NULL, NULL };
gid_t *groups = *groupsp;
status = internal_setgrent (domainname, &intern);
if (status != NSS_STATUS_SUCCESS)
return status;
tmpbuf = __alloca (buflen);
do
{
while ((status =
internal_getgrent_r (&grpbuf, tmpbuf, buflen, errnop,
&intern)) == NSS_STATUS_TRYAGAIN
&& *errnop == ERANGE)
tmpbuf = extend_alloca (tmpbuf, buflen, 2 * buflen);
if (status != NSS_STATUS_SUCCESS)
goto done;
g = &grpbuf;
if (g->gr_gid != group)
{
char **m;
for (m = g->gr_mem; *m != NULL; ++m)
if (strcmp (*m, user) == 0)
{
/* Matches user. Insert this group. */
if (*start == *size)
{
/* Need a bigger buffer. */
gid_t *newgroups;
long int newsize;
if (limit > 0 && *size == limit)
/* We reached the maximum. */
goto done;
if (limit <= 0)
newsize = 2 * *size;
else
newsize = MIN (limit, 2 * *size);
newgroups = realloc (groups, newsize * sizeof (*groups));
if (newgroups == NULL)
goto done;
*groupsp = groups = newgroups;
*size = newsize;
}
groups[*start] = g->gr_gid;
*start += 1;
break;
}
}
}
while (status == NSS_STATUS_SUCCESS);
done:
while (intern.start != NULL)
{
intern.next = intern.start;
intern.start = intern.start->next;
free (intern.next);
}
return NSS_STATUS_SUCCESS;
}