NEX-14547 Get UNIX group info. from AD/LDAP with partial RFC2307 schema
NEX-13132 smbd dumping core in nss_ldap.so.1`getbymember
Reviewed by: Matt Barden <matt.barden@nexenta.com>
Reviewed by: Evan Layton <evan.layton@nexenta.com>

*** 18,27 ****
--- 18,28 ----
   *
   * CDDL HEADER END
   */
  /*
   * Copyright (c) 1999, 2010, Oracle and/or its affiliates. All rights reserved.
+  * Copyright 2017 Nexenta Systems, Inc.  All rights reserved.
   */
  
  #include <stdio.h>
  #include <sys/types.h>
  #include <stdlib.h>
*** 225,235 ****
                  return (NULL);
  
          if ((rdns = ldap_explode_dn(dn, 0)) == NULL)
                  return (NULL);
  
!         for (nRdn = 0; rdns[nRdn] != NULL; nRdn++);
  
          if ((mapped_rdns = (char **)calloc(nRdn, sizeof (char *))) == NULL) {
                  ldap_value_free(rdns);
                  return (NULL);
          }
--- 226,237 ----
                  return (NULL);
  
          if ((rdns = ldap_explode_dn(dn, 0)) == NULL)
                  return (NULL);
  
!         for (nRdn = 0; rdns[nRdn] != NULL; nRdn++)
!                 ;
  
          if ((mapped_rdns = (char **)calloc(nRdn, sizeof (char *))) == NULL) {
                  ldap_value_free(rdns);
                  return (NULL);
          }
*** 4228,4239 ****
--- 4230,4320 ----
          (void) __ns_ldap_freeResult(&result);
          result = NULL;
          return (NS_LDAP_SUCCESS);
  }
  
+ #define _P_UID  "uid"
+ static const char *dn2uid_attrs[] = {
+         _P_CN,
+         _P_UID,
+         (char *)NULL
+ };
  
  /*ARGSUSED*/
+ int
+ __ns_ldap_dn2uid(const char *dn,
+                 char **userID,
+                 const ns_cred_t *cred,  /* cred is ignored */
+                 ns_ldap_error_t **errorp)
+ {
+         ns_ldap_result_t        *result = NULL;
+         char            *filter, *userdata;
+         char            errstr[MAXERROR];
+         char            **value;
+         int             rc = 0;
+         size_t          len;
+ 
+         *errorp = NULL;
+         *userID = NULL;
+         if ((dn == NULL) || (dn[0] == '\0'))
+                 return (NS_LDAP_INVALID_PARAM);
+ 
+         len = strlen(UIDDNFILTER) + strlen(dn) + 1;
+         filter = (char *)malloc(len);
+         if (filter == NULL) {
+                 return (NS_LDAP_MEMORY);
+         }
+         (void) snprintf(filter, len, UIDDNFILTER, dn);
+ 
+         len = strlen(UIDDNFILTER_SSD) + strlen(dn) + 1;
+         userdata = (char *)malloc(len);
+         if (userdata == NULL) {
+                 return (NS_LDAP_MEMORY);
+         }
+         (void) snprintf(userdata, len, UIDDNFILTER_SSD, dn);
+ 
+         /*
+          * Unlike uid2dn, we DO want attribute mapping, so that
+          * "uid" is mapped to/from samAccountName, for example.
+          */
+         rc = __ns_ldap_list("passwd", filter,
+             __s_api_merge_SSD_filter,
+             dn2uid_attrs, cred, 0,
+             &result, errorp, NULL,
+             userdata);
+         free(filter);
+         filter = NULL;
+         free(userdata);
+         userdata = NULL;
+         if (rc != NS_LDAP_SUCCESS)
+                 goto out;
+ 
+         if (result->entries_count > 1) {
+                 (void) sprintf(errstr,
+                     gettext("Too many entries are returned for %s"), dn);
+                 MKERROR(LOG_WARNING, *errorp, NS_LDAP_INTERNAL, strdup(errstr),
+                     NULL);
+                 rc = NS_LDAP_INTERNAL;
+                 goto out;
+         }
+ 
+         value = __ns_ldap_getAttr(result->entry, _P_UID);
+         if (value == NULL || value[0] == NULL) {
+                 rc = NS_LDAP_NOTFOUND;
+                 goto out;
+         }
+ 
+         *userID = strdup(value[0]);
+         rc = NS_LDAP_SUCCESS;
+ 
+ out:
+         (void) __ns_ldap_freeResult(&result);
+         result = NULL;
+         return (rc);
+ }
+ 
+ /*ARGSUSED*/
  int
  __ns_ldap_host2dn(const char *host,
                  const char *domain,
                  char **hostDN,
                  const ns_cred_t *cred,  /* cred is ignored */