/*
group.c - group entry lookup routines
Parts of this file were part of the nss_ldap library (as ldap-grp.c)
which has been forked into the nss-pam-ldapd library.
Copyright (C) 1997-2006 Luke Howard
Copyright (C) 2006 West Consulting
Copyright (C) 2006-2015 Arthur de Jong
Copyright (C) 2013 Steve Hill
This 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.
This 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 this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301 USA
*/
#include "config.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
/* for gid_t */
#include <grp.h>
#include "common/set.h"
#include "common.h"
#include "log.h"
#include "myldap.h"
#include "cfg.h"
#include "attmap.h"
#include "compat/strndup.h"
/* ( nisSchema.2.2 NAME 'posixGroup' SUP top STRUCTURAL
* DESC 'Abstraction of a group of accounts'
* MUST ( cn $ gidNumber )
* MAY ( userPassword $ memberUid $ description ) )
*
* apart from the above a member attribute is also supported that
* may contains a DN of a user
*
* nested groups (groups that are member of a group) are currently
* not supported
*/
/* the search base for searches */
const char *group_bases[NSS_LDAP_CONFIG_MAX_BASES] = { NULL };
/* the search scope for searches */
int group_scope = LDAP_SCOPE_DEFAULT;
/* the basic search filter for searches */
const char *group_filter = "(objectClass=posixGroup)";
/* the attributes to request with searches */
const char *attmap_group_cn = "cn";
const char *attmap_group_userPassword = "\"*\"";
const char *attmap_group_gidNumber = "gidNumber";
const char *attmap_group_memberUid = "memberUid";
const char *attmap_group_member = "member";
/* special property for objectSid-based searches
(these are already LDAP-escaped strings) */
static char *gidSid = NULL;
/* BUILTIN SID definitions */
static char *builtinSid = NULL;
const gid_t min_builtin_rid = 544;
const gid_t max_builtin_rid = 552;
/* default values for attributes */
static const char *default_group_userPassword = "*"; /* unmatchable */
/* the attribute list to request with searches */
static const char **group_attrs = NULL;
/* the attribute list for bymember searches (without member attributes) */
static const char **group_bymember_attrs = NULL;
/* create a search filter for searching a group entry
by name, return -1 on errors */
static int mkfilter_group_byname(const char *name,
char *buffer, size_t buflen)
{
char safename[BUFLEN_SAFENAME];
/* escape attribute */
if (myldap_escape(name, safename, sizeof(safename)))
{
log_log(LOG_ERR, "mkfilter_group_byname(): safename buffer too small");
return -1;
}
/* build filter */
return mysnprintf(buffer, buflen, "(&%s(%s=%s))",
group_filter, attmap_group_cn, safename);
}
/* create a search filter for searching a group entry
by gid, return -1 on errors */
static int mkfilter_group_bygid(gid_t gid, char *buffer, size_t buflen)
{
gid -= nslcd_cfg->nss_gid_offset;
/* if searching for a Windows domain SID */
if (gidSid != NULL)
{
/* the given gid is a BUILTIN gid, the SID prefix is not the domain SID */
if ((gid >= min_builtin_rid) && (gid <= max_builtin_rid))
return mysnprintf(buffer, buflen, "(&%s(%s=%s\\%02x\\%02x\\%02x\\%02x))",
group_filter, attmap_group_gidNumber, builtinSid,
(int)(gid & 0xff), (int)((gid >> 8) & 0xff),
(int)((gid >> 16) & 0xff), (int)((gid >> 24) & 0xff));
return mysnprintf(buffer, buflen, "(&%s(%s=%s\\%02x\\%02x\\%02x\\%02x))",
group_filter, attmap_group_gidNumber, gidSid,
(int)(gid & 0xff), (int)((gid >> 8) & 0xff),
(int)((gid >> 16) & 0xff), (int)((gid >> 24) & 0xff));
}
else
{
return mysnprintf(buffer, buflen, "(&%s(%s=%lu))",
group_filter, attmap_group_gidNumber, (unsigned long int)gid);
}
}
/* create a search filter for searching a group entry
by member uid, return -1 on errors */
static int mkfilter_group_bymember(MYLDAP_SESSION *session,
const char *uid,
char *buffer, size_t buflen)
{
char dn[BUFLEN_DN];
char safeuid[BUFLEN_SAFENAME];
char safedn[BUFLEN_SAFEDN];
/* escape attribute */
if (myldap_escape(uid, safeuid, sizeof(safeuid)))
{
log_log(LOG_ERR, "mkfilter_group_bymember(): safeuid buffer too small");
return -1;
}
/* try to translate uid to DN */
if ((strcasecmp(attmap_group_member, "\"\"") == 0) ||
(uid2dn(session, uid, dn, sizeof(dn)) == NULL))
return mysnprintf(buffer, buflen, "(&%s(%s=%s))",
group_filter, attmap_group_memberUid, safeuid);
/* escape DN */
if (myldap_escape(dn, safedn, sizeof(safedn)))
{
log_log(LOG_ERR, "mkfilter_group_bymember(): safedn buffer too small");
return -1;
}
/* also lookup using user DN */
return mysnprintf(buffer, buflen, "(&%s(|(%s=%s)(%s=%s)))",
group_filter,
attmap_group_memberUid, safeuid,
attmap_group_member, safedn);
}
static int mkfilter_group_bymemberdn(const char *dn,
char *buffer, size_t buflen)
{
char safedn[BUFLEN_SAFEDN];
/* escape DN */
if (myldap_escape(dn, safedn, sizeof(safedn)))
{
log_log(LOG_ERR, "mkfilter_group_bymemberdn(): safedn buffer too small");
return -1;
}
return mysnprintf(buffer, buflen,
"(&%s(%s=%s))",
group_filter,
attmap_group_member, safedn);
}
void group_init(void)
{
int i;
SET *set;
/* set up search bases */
if (group_bases[0] == NULL)
for (i = 0; i < NSS_LDAP_CONFIG_MAX_BASES; i++)
group_bases[i] = nslcd_cfg->bases[i];
/* set up scope */
if (group_scope == LDAP_SCOPE_DEFAULT)
group_scope = nslcd_cfg->scope;
/* special case when gidNumber references objectSid */
if (strncasecmp(attmap_group_gidNumber, "objectSid:", 10) == 0)
{
gidSid = sid2search(attmap_group_gidNumber + 10);
builtinSid = sid2search("S-1-5-32");
attmap_group_gidNumber = strndup(attmap_group_gidNumber, 9);
}
/* set up attribute list */
set = set_new();
attmap_add_attributes(set, attmap_group_cn);
attmap_add_attributes(set, attmap_group_userPassword);
attmap_add_attributes(set, attmap_group_gidNumber);
if (!nslcd_cfg->nss_getgrent_skipmembers)
{
attmap_add_attributes(set, attmap_group_memberUid);
attmap_add_attributes(set, attmap_group_member);
}
group_attrs = set_tolist(set);
if (group_attrs == NULL)
{
log_log(LOG_CRIT, "malloc() failed to allocate memory");
exit(EXIT_FAILURE);
}
set_free(set);
/* set up bymember attribute list */
set = set_new();
attmap_add_attributes(set, attmap_group_cn);
attmap_add_attributes(set, attmap_group_userPassword);
attmap_add_attributes(set, attmap_group_gidNumber);
group_bymember_attrs = set_tolist(set);
if (group_bymember_attrs == NULL)
{
log_log(LOG_CRIT, "malloc() failed to allocate memory");
exit(EXIT_FAILURE);
}
set_free(set);
}
static int do_write_group(TFILE *fp, MYLDAP_ENTRY *entry,
const char **names, gid_t gids[], int numgids,
const char *passwd, const char **members,
const char *reqname)
{
int32_t tmpint32, tmp2int32, tmp3int32;
int i, j;
/* write entries for all names and gids */
for (i = 0; names[i] != NULL; i++)
{
if (!isvalidname(names[i]))
{
log_log(LOG_WARNING, "%s: %s: denied by validnames option",
myldap_get_dn(entry), attmap_group_cn);
}
else if ((reqname == NULL) || (STR_CMP(reqname, names[i]) == 0))
{
for (j = 0; j < numgids; j++)
{
WRITE_INT32(fp, NSLCD_RESULT_BEGIN);
WRITE_STRING(fp, names[i]);
WRITE_STRING(fp, passwd);
WRITE_INT32(fp, gids[j]);
WRITE_STRINGLIST(fp, members);
}
}
}
return 0;
}
static void getmembers(MYLDAP_ENTRY *entry, MYLDAP_SESSION *session,
SET *members, SET *seen, SET *subgroups)
{
char buf[BUFLEN_NAME];
int i;
const char **values;
const char ***derefs;
/* add the memberUid values */
values = myldap_get_values(entry, attmap_group_memberUid);
if (values != NULL)
for (i = 0; values[i] != NULL; i++)
{
/* only add valid usernames */
if (isvalidname(values[i]))
set_add(members, values[i]);
}
/* skip rest if attmap_group_member is blank */
if (strcasecmp(attmap_group_member, "\"\"") == 0)
return;
/* add deref'd entries if we have them*/
derefs = myldap_get_deref_values(entry, attmap_group_member, attmap_passwd_uid);
if (derefs != NULL)
{
/* add deref'd uid attributes */
for (i = 0; derefs[0][i] != NULL; i++)
set_add(members, derefs[0][i]);
/* add non-deref'd attribute values as subgroups */
for (i = 0; derefs[1][i] != NULL; i++)
{
if ((seen == NULL) || (!set_contains(seen, derefs[1][i])))
{
if (seen != NULL)
set_add(seen, derefs[1][i]);
if (subgroups != NULL)
set_add(subgroups, derefs[1][i]);
}
}
return; /* no need to parse the member attribute ourselves */
}
/* add the member values */
values = myldap_get_values(entry, attmap_group_member);
if (values != NULL)
for (i = 0; values[i] != NULL; i++)
{
if ((seen == NULL) || (!set_contains(seen, values[i])))
{
if (seen != NULL)
set_add(seen, values[i]);
/* transform the DN into a uid (dn2uid() already checks validity) */
if (dn2uid(session, values[i], buf, sizeof(buf)) != NULL)
set_add(members, buf);
/* wasn't a UID - try handling it as a nested group */
else if (subgroups != NULL)
set_add(subgroups, values[i]);
}
}
}
/* the maximum number of gidNumber attributes per entry */
#define MAXGIDS_PER_ENTRY 5
static int write_group(TFILE *fp, MYLDAP_ENTRY *entry, const char *reqname,
const gid_t *reqgid, int wantmembers,
MYLDAP_SESSION *session)
{
const char **names, **gidvalues;
const char *passwd;
const char **members = NULL;
SET *set, *seen=NULL, *subgroups=NULL;
gid_t gids[MAXGIDS_PER_ENTRY];
int numgids;
char *tmp;
char passbuffer[BUFLEN_PASSWORDHASH];
MYLDAP_SEARCH *search;
MYLDAP_ENTRY *entry2;
int rc;
/* get group name (cn) */
names = myldap_get_values(entry, attmap_group_cn);
if ((names == NULL) || (names[0] == NULL))
{
log_log(LOG_WARNING, "%s: %s: missing",
myldap_get_dn(entry), attmap_group_cn);
return 0;
}
/* get the group id(s) */
if (reqgid != NULL)
{
gids[0] = *reqgid;
numgids = 1;
}
else
{
gidvalues = myldap_get_values_len(entry, attmap_group_gidNumber);
if ((gidvalues == NULL) || (gidvalues[0] == NULL))
{
log_log(LOG_WARNING, "%s: %s: missing",
myldap_get_dn(entry), attmap_group_gidNumber);
return 0;
}
for (numgids = 0; (numgids < MAXGIDS_PER_ENTRY) && (gidvalues[numgids] != NULL); numgids++)
{
if (gidSid != NULL)
gids[numgids] = (gid_t)binsid2id(gidvalues[numgids]);
else
{
errno = 0;
gids[numgids] = strtogid(gidvalues[numgids], &tmp, 10);
if ((*(gidvalues[numgids]) == '\0') || (*tmp != '\0'))
{
log_log(LOG_WARNING, "%s: %s: non-numeric",
myldap_get_dn(entry), attmap_group_gidNumber);
return 0;
}
else if ((errno != 0) || (strchr(gidvalues[numgids], '-') != NULL))
{
log_log(LOG_WARNING, "%s: %s: out of range",
myldap_get_dn(entry), attmap_group_gidNumber);
return 0;
}
}
gids[numgids] += nslcd_cfg->nss_gid_offset;
}
}
/* get group passwd (userPassword) (use only first entry) */
passwd = get_userpassword(entry, attmap_group_userPassword,
passbuffer, sizeof(passbuffer));
if (passwd == NULL)
passwd = default_group_userPassword;
/* get group members (memberUid&member) */
if (wantmembers)
{
set = set_new();
if (set != NULL)
{
if (nslcd_cfg->nss_nested_groups)
{
seen = set_new();
subgroups = set_new();
}
/* collect the members from this group */
getmembers(entry, session, set, seen, subgroups);
/* add the members of any nested groups */
if (subgroups != NULL)
{
while ((tmp = set_pop(subgroups)) != NULL)
{
search = myldap_search(session, tmp, LDAP_SCOPE_BASE, group_filter, group_attrs, NULL);
if (search != NULL)
while ((entry2 = myldap_get_entry(search, NULL)) != NULL)
getmembers(entry2, session, set, seen, subgroups);
free(tmp);
}
}
members = set_tolist(set);
set_free(set);
if (seen != NULL)
set_free(seen);
if (subgroups != NULL)
set_free(subgroups);
}
}
/* write entries (split to a separate function so we can ensure the call
to free() below in case a write fails) */
rc = do_write_group(fp, entry, names, gids, numgids, passwd, members,
reqname);
/* free and return */
if (members != NULL)
free(members);
return rc;
}
NSLCD_HANDLE(
group, byname, NSLCD_ACTION_GROUP_BYNAME,
char name[BUFLEN_NAME];
char filter[BUFLEN_FILTER];
READ_STRING(fp, name);
log_setrequest("group=\"%s\"", name);
if (!isvalidname(name))
{
log_log(LOG_WARNING, "request denied by validnames option");
return -1;
},
mkfilter_group_byname(name, filter, sizeof(filter)),
write_group(fp, entry, name, NULL, 1, session)
)
NSLCD_HANDLE(
group, bygid, NSLCD_ACTION_GROUP_BYGID,
gid_t gid;
char filter[BUFLEN_FILTER];
READ_INT32(fp, gid);
log_setrequest("group=%lu", (unsigned long int)gid);,
mkfilter_group_bygid(gid, filter, sizeof(filter)),
write_group(fp, entry, NULL, &gid, 1, session)
)
int nslcd_group_bymember(TFILE *fp, MYLDAP_SESSION *session)
{
/* define common variables */
int32_t tmpint32;
MYLDAP_SEARCH *search;
MYLDAP_ENTRY *entry;
const char *dn;
const char *base;
int rc, i;
char name[BUFLEN_NAME];
char filter[BUFLEN_FILTER];
SET *seen=NULL, *tocheck=NULL;
/* read request parameters */
READ_STRING(fp, name);
log_setrequest("group/member=\"%s\"", name);
/* validate request */
if (!isvalidname(name))
{
log_log(LOG_WARNING, "request denied by validnames option");
return -1;
}
if ((nslcd_cfg->nss_initgroups_ignoreusers != NULL) &&
set_contains(nslcd_cfg->nss_initgroups_ignoreusers, name))
{
log_log(LOG_DEBUG, "ignored group member");
/* just end the request, returning no results */
WRITE_INT32(fp, NSLCD_VERSION);
WRITE_INT32(fp, NSLCD_ACTION_GROUP_BYMEMBER);
WRITE_INT32(fp, NSLCD_RESULT_END);
return 0;
}
/* write the response header */
WRITE_INT32(fp, NSLCD_VERSION);
WRITE_INT32(fp, NSLCD_ACTION_GROUP_BYMEMBER);
/* prepare the search filter */
if (mkfilter_group_bymember(session, name, filter, sizeof(filter)))
{
log_log(LOG_WARNING, "nslcd_group_bymember(): filter buffer too small");
return -1;
}
if ((nslcd_cfg->nss_nested_groups) && (strcasecmp(attmap_group_member, "\"\"") != 0))
{
seen = set_new();
tocheck = set_new();
if ((seen != NULL) && (tocheck == NULL))
{
set_free(seen);
seen = NULL;
}
else if ((tocheck != NULL) && (seen == NULL))
{
set_free(tocheck);
tocheck = NULL;
}
}
/* perform a search for each search base */
for (i = 0; (base = group_bases[i]) != NULL; i++)
{
/* do the LDAP search */
search = myldap_search(session, base, group_scope, filter,
group_bymember_attrs, NULL);
if (search == NULL)
{
if (seen != NULL)
{
set_free(seen);
set_free(tocheck);
}
return -1;
}
/* go over results */
while ((entry = myldap_get_entry(search, &rc)) != NULL)
{
if ((seen == NULL) || (!set_contains(seen, dn = myldap_get_dn(entry))))
{
if (seen != NULL)
{
set_add(seen, dn);
set_add(tocheck, dn);
}
if (write_group(fp, entry, NULL, NULL, 0, session))
{
if (seen != NULL)
{
set_free(seen);
set_free(tocheck);
}
return -1;
}
}
}
}
/* write possible parent groups */
if (tocheck != NULL)
{
while ((dn = set_pop(tocheck)) != NULL)
{
/* make filter for finding groups with our group as member */
if (mkfilter_group_bymemberdn(dn, filter, sizeof(filter)))
{
log_log(LOG_WARNING, "nslcd_group_bymember(): filter buffer too small");
free((void *)dn);
set_free(seen);
set_free(tocheck);
return -1;
}
free((void *)dn);
/* do the LDAP searches */
for (i = 0; (base = group_bases[i]) != NULL; i++)
{
search = myldap_search(session, base, group_scope, filter, group_bymember_attrs, NULL);
if (search != NULL)
{
while ((entry = myldap_get_entry(search, NULL)) != NULL)
{
dn = myldap_get_dn(entry);
if (!set_contains(seen, dn))
{
set_add(seen, dn);
set_add(tocheck, dn);
if (write_group(fp, entry, NULL, NULL, 0, session))
{
set_free(seen);
set_free(tocheck);
return -1;
}
}
}
}
}
}
set_free(seen);
set_free(tocheck);
}
/* write the final result code */
if (rc == LDAP_SUCCESS)
{
WRITE_INT32(fp, NSLCD_RESULT_END);
}
return 0;
}
NSLCD_HANDLE(
group, all, NSLCD_ACTION_GROUP_ALL,
const char *filter;
log_setrequest("group(all)");,
(filter = group_filter, 0),
write_group(fp, entry, NULL, NULL, 1, session)
)