nsswitch/wins.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    a WINS nsswitch module
   4    Copyright (C) Andrew Tridgell 1999
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18
  19 */
  20
  21 #include "includes.h"
  22 #include "nsswitch/winbind_nss.h"
  23 #include "nsswitch/libwbclient/wbclient.h"
  24
  25 #ifdef HAVE_NS_API_H
  26
  27 #include <ns_daemon.h>
  28 #endif
  29
  30 #if HAVE_PTHREAD_H
  31 #include <pthread.h>
  32 #endif
  33
  34 #if HAVE_PTHREAD
  35 static pthread_mutex_t wins_nss_mutex = PTHREAD_MUTEX_INITIALIZER;
  36 #endif
  37
  38 #ifndef INADDRSZ
  39 #define INADDRSZ 4
  40 #endif
  41
  42 NSS_STATUS _nss_wins_gethostbyname_r(const char *hostname, struct hostent *he,
  43                           char *buffer, size_t buflen, int *h_errnop);
  44 NSS_STATUS _nss_wins_gethostbyname2_r(const char *name, int af, struct hostent *he,
  45                            char *buffer, size_t buflen, int *h_errnop);
  46
  47 static char *lookup_byname_backend(const char *name)
  48 {
  49         const char *p;
  50         char *ip, *ipp;
  51         size_t nbt_len;
  52         wbcErr result;
  53
  54         nbt_len = strlen(name);
  55         if (nbt_len > MAX_NETBIOSNAME_LEN - 1) {
  56                 return NULL;
  57         }
  58         p = strchr(name, '.');
  59         if (p != NULL) {
  60                 return NULL;
  61         }
  62
  63         result = wbcResolveWinsByName(name, &ip);
  64         if (result != WBC_ERR_SUCCESS) {
  65                 return NULL;
  66         }
  67
  68         ipp = strchr(ip, '\t');
  69         if (ipp != NULL) {
  70                 *ipp = '\0';
  71         }
  72
  73         return ip;
  74 }
  75
  76 #ifdef HAVE_NS_API_H
  77
  78 static char *lookup_byaddr_backend(const char *ip)
  79 {
  80         wbcErr result;
  81         char *name = NULL;
  82
  83         result = wbcResolveWinsByIP(ip, &name);
  84         if (result != WBC_ERR_SUCCESS) {
  85                 return NULL;
  86         }
  87
  88         return name;
  89 }
  90
  91 /* IRIX version */
  92
  93 int init(void)
  94 {
  95         bool ok;
  96
  97         nsd_logprintf(NSD_LOG_MIN, "entering init (wins)\n");
  98
  99         ok = nss_wins_init();
 100         if (!ok) {
 101                 return NSD_ERROR;
 102         }
 103
 104         return NSD_OK;
 105 }
 106
 107 int lookup(nsd_file_t *rq)
 108 {
 109         char *map;
 110         char *key;
 111         char *addr;
 112         int i, count, len, size;
 113         char response[1024];
 114         bool found = False;
 115
 116         nsd_logprintf(NSD_LOG_MIN, "entering lookup (wins)\n");
 117         if (! rq)
 118                 return NSD_ERROR;
 119
 120         map = nsd_attr_fetch_string(rq->f_attrs, "table", (char*)0);
 121         if (! map) {
 122                 rq->f_status = NS_FATAL;
 123                 return NSD_ERROR;
 124         }
 125
 126         key = nsd_attr_fetch_string(rq->f_attrs, "key", (char*)0);
 127         if (! key || ! *key) {
 128                 rq->f_status = NS_FATAL;
 129                 return NSD_ERROR;
 130         }
 131
 132         response[0] = '\0';
 133         len = sizeof(response) - 2;
 134
 135         /*
 136          * response needs to be a string of the following format
 137          * ip_address[ ip_address]*\tname[ alias]*
 138          */
 139         if (strcasecmp_m(map,"hosts.byaddr") == 0) {
 140                 char *name;
 141
 142                 name = lookup_byaddr_backend(key);
 143                 if (name != NULL) {
 144                         size = strlen(key) + 1;
 145                         if (size > len) {
 146                                 return NSD_ERROR;
 147                         }
 148                         len -= size;
 149                         strncat(response,key,size);
 150                         strncat(response,"\t",1);
 151
 152                         size = strlen(name) + 1;
 153                         if (size > len) {
 154                                 return NSD_ERROR;
 155                         }
 156                         len -= size;
 157                         strncat(response, name, size);
 158                         strncat(response, " ", 1);
 159                         found = True;
 160                 }
 161                 response[strlen(response)-1] = '\n';
 162         } else if (strcasecmp_m(map,"hosts.byname") == 0) {
 163                 char *ip;
 164
 165                 ip = lookup_byname_backend(key);
 166                 if (ip != NULL) {
 167                         size = strlen(ip) + 1;
 168                         if (size > len) {
 169                                 wbcFreeMemory(ip);
 170                                 return NSD_ERROR;
 171                         }
 172                         len -= size;
 173                         strncat(response,ip,size);
 174                         strncat(response,"\t",1);
 175                         size = strlen(key) + 1;
 176                         wbcFreeMemory(ip);
 177                         if (size > len) {
 178                                 return NSD_ERROR;
 179                         }
 180                         strncat(response,key,size);
 181                         strncat(response,"\n",1);
 182
 183                         found = True;
 184                 }
 185         }
 186
 187         if (found) {
 188             nsd_logprintf(NSD_LOG_LOW, "lookup (wins %s) %s\n",map,response);
 189             nsd_set_result(rq,NS_SUCCESS,response,strlen(response),VOLATILE);
 190             return NSD_OK;
 191         }
 192         nsd_logprintf(NSD_LOG_LOW, "lookup (wins) not found\n");
 193         rq->f_status = NS_NOTFOUND;
 194         return NSD_NEXT;
 195 }
 196
 197 #else
 198
 199 /* Allocate some space from the nss static buffer.  The buffer and buflen
 200    are the pointers passed in by the C library to the _nss_*_*
 201    functions. */
 202
 203 static char *get_static(char **buffer, size_t *buflen, size_t len)
 204 {
 205         char *result;
 206
 207         /* Error check.  We return false if things aren't set up right, or
 208            there isn't enough buffer space left. */
 209
 210         if ((buffer == NULL) || (buflen == NULL) || (*buflen < len)) {
 211                 return NULL;
 212         }
 213
 214         /* Return an index into the static buffer */
 215
 216         result = *buffer;
 217         *buffer += len;
 218         *buflen -= len;
 219
 220         return result;
 221 }
 222
 223 /****************************************************************************
 224 gethostbyname() - we ignore any domain portion of the name and only
 225 handle names that are at most 15 characters long
 226   **************************************************************************/
 227 NSS_STATUS
 228 _nss_wins_gethostbyname_r(const char *hostname, struct hostent *he,
 229                           char *buffer, size_t buflen, int *h_errnop)
 230 {
 231         NSS_STATUS nss_status = NSS_STATUS_SUCCESS;
 232         char *ip;
 233         struct in_addr in;
 234         int i;
 235         fstring name;
 236         size_t namelen;
 237         int rc;
 238
 239 #if HAVE_PTHREAD
 240         pthread_mutex_lock(&wins_nss_mutex);
 241 #endif
 242
 243         memset(he, '\0', sizeof(*he));
 244         fstrcpy(name, hostname);
 245
 246         /* Do lookup */
 247
 248         ip = lookup_byname_backend(name);
 249         if (ip == NULL) {
 250                 nss_status = NSS_STATUS_NOTFOUND;
 251                 goto out;
 252         }
 253
 254         rc = inet_pton(AF_INET, ip, &in);
 255         wbcFreeMemory(ip);
 256         if (rc == 0) {
 257                 nss_status = NSS_STATUS_TRYAGAIN;
 258                 goto out;
 259         }
 260
 261         /* Copy h_name */
 262
 263         namelen = strlen(name) + 1;
 264
 265         if ((he->h_name = get_static(&buffer, &buflen, namelen)) == NULL) {
 266                 nss_status = NSS_STATUS_TRYAGAIN;
 267                 goto out;
 268         }
 269
 270         memcpy(he->h_name, name, namelen);
 271
 272         /* Copy h_addr_list, align to pointer boundary first */
 273
 274         if ((i = (unsigned long)(buffer) % sizeof(char*)) != 0)
 275                 i = sizeof(char*) - i;
 276
 277         if (get_static(&buffer, &buflen, i) == NULL) {
 278                 nss_status = NSS_STATUS_TRYAGAIN;
 279                 goto out;
 280         }
 281
 282         if ((he->h_addr_list = (char **)get_static(
 283                      &buffer, &buflen, 2 * sizeof(char *))) == NULL) {
 284                 nss_status = NSS_STATUS_TRYAGAIN;
 285                 goto out;
 286         }
 287
 288         if ((he->h_addr_list[0] = get_static(&buffer, &buflen,
 289                                              INADDRSZ)) == NULL) {
 290                 nss_status = NSS_STATUS_TRYAGAIN;
 291                 goto out;
 292         }
 293
 294         memcpy(he->h_addr_list[0], &in, INADDRSZ);
 295
 296         he->h_addr_list[1] = NULL;
 297
 298         /* Set h_addr_type and h_length */
 299
 300         he->h_addrtype = AF_INET;
 301         he->h_length = INADDRSZ;
 302
 303         /* Set h_aliases */
 304
 305         if ((i = (unsigned long)(buffer) % sizeof(char*)) != 0)
 306                 i = sizeof(char*) - i;
 307
 308         if (get_static(&buffer, &buflen, i) == NULL) {
 309                 nss_status = NSS_STATUS_TRYAGAIN;
 310                 goto out;
 311         }
 312
 313         if ((he->h_aliases = (char **)get_static(
 314                      &buffer, &buflen, sizeof(char *))) == NULL) {
 315                 nss_status = NSS_STATUS_TRYAGAIN;
 316                 goto out;
 317         }
 318
 319         he->h_aliases[0] = NULL;
 320
 321         nss_status = NSS_STATUS_SUCCESS;
 322
 323   out:
 324
 325 #if HAVE_PTHREAD
 326         pthread_mutex_unlock(&wins_nss_mutex);
 327 #endif
 328         return nss_status;
 329 }
 330
 331
 332 NSS_STATUS
 333 _nss_wins_gethostbyname2_r(const char *name, int af, struct hostent *he,
 334                            char *buffer, size_t buflen, int *h_errnop)
 335 {
 336         NSS_STATUS nss_status;
 337
 338         if(af!=AF_INET) {
 339                 *h_errnop = NO_DATA;
 340                 nss_status = NSS_STATUS_UNAVAIL;
 341         } else {
 342                 nss_status = _nss_wins_gethostbyname_r(
 343                                 name, he, buffer, buflen, h_errnop);
 344         }
 345         return nss_status;
 346 }
 347 #endif