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
  24 #ifdef HAVE_NS_API_H
  25
  26 #include <ns_daemon.h>
  27 #endif
  28
  29 #if HAVE_PTHREAD_H
  30 #include <pthread.h>
  31 #endif
  32
  33 #if HAVE_PTHREAD
  34 static pthread_mutex_t wins_nss_mutex = PTHREAD_MUTEX_INITIALIZER;
  35 #endif
  36
  37 #ifndef INADDRSZ
  38 #define INADDRSZ 4
  39 #endif
  40
  41 static int initialised;
  42
  43 NSS_STATUS _nss_wins_gethostbyname_r(const char *hostname, struct hostent *he,
  44                           char *buffer, size_t buflen, int *h_errnop);
  45 NSS_STATUS _nss_wins_gethostbyname2_r(const char *name, int af, struct hostent *he,
  46                            char *buffer, size_t buflen, int *h_errnop);
  47
  48 static void nss_wins_init(void)
  49 {
  50         initialised = 1;
  51         lp_set_cmdline("log level", "0");
  52
  53         TimeInit();
  54         setup_logging("nss_wins",False);
  55         lp_load(get_dyn_CONFIGFILE(),True,False,False,True);
  56         load_interfaces();
  57 }
  58
  59 static struct in_addr *lookup_byname_backend(const char *name, int *count)
  60 {
  61         TALLOC_CTX *frame;
  62         struct sockaddr_storage *address = NULL;
  63         struct in_addr *ret = NULL;
  64         NTSTATUS status;
  65         const char *p;
  66         size_t nbt_len;
  67         int j;
  68
  69         if (!initialised) {
  70                 nss_wins_init();
  71         }
  72
  73         *count = 0;
  74
  75         nbt_len = strlen(name);
  76         if (nbt_len > MAX_NETBIOSNAME_LEN - 1) {
  77                 return NULL;
  78         }
  79         p = strchr(name, '.');
  80         if (p != NULL) {
  81                 return NULL;
  82         }
  83
  84         frame = talloc_stackframe();
  85         /* always try with wins first */
  86         status = resolve_wins(name, 0x00, talloc_tos(),
  87                               &address, count);
  88         if (NT_STATUS_IS_OK(status)) {
  89                 if ( (ret = SMB_MALLOC_P(struct in_addr)) == NULL ) {
  90                         TALLOC_FREE(frame);
  91                         return NULL;
  92                 }
  93                 if (address[0].ss_family != AF_INET) {
  94                         free(ret);
  95                         TALLOC_FREE(frame);
  96                         return NULL;
  97                 }
  98                 *ret = ((struct sockaddr_in *)(void *)address)
  99                         ->sin_addr;
 100                 TALLOC_FREE(frame);
 101                 return ret;
 102         }
 103
 104         /* uggh, we have to broadcast to each interface in turn */
 105         for (j=iface_count() - 1;j >= 0;j--) {
 106                 const struct in_addr *bcast = iface_n_bcast_v4(j);
 107                 struct sockaddr_storage ss;
 108                 struct sockaddr_storage *pss;
 109
 110                 if (!bcast) {
 111                         continue;
 112                 }
 113                 in_addr_to_sockaddr_storage(&ss, *bcast);
 114                 status = name_query(name, 0x00, True, True, &ss,
 115                                     talloc_tos(), &pss, count, NULL);
 116                 if (NT_STATUS_IS_OK(status) && (*count > 0)) {
 117                         if ((ret = SMB_MALLOC_P(struct in_addr)) == NULL) {
 118                                 TALLOC_FREE(frame);
 119                                 return NULL;
 120                         }
 121                         *ret = ((struct sockaddr_in *)pss)->sin_addr;
 122                         break;
 123                 }
 124         }
 125         TALLOC_FREE(frame);
 126         return ret;
 127 }
 128
 129 #ifdef HAVE_NS_API_H
 130
 131 static struct node_status *lookup_byaddr_backend(char *addr, int *count)
 132 {
 133         struct sockaddr_storage ss;
 134         struct nmb_name nname;
 135         struct node_status *result;
 136         NTSTATUS status;
 137
 138         if (!initialised) {
 139                 nss_wins_init();
 140         }
 141
 142         make_nmb_name(&nname, "*", 0);
 143         if (!interpret_string_addr(&ss, addr, AI_NUMERICHOST)) {
 144                 return NULL;
 145         }
 146         status = node_status_query(NULL, &nname, &ss, &result, count, NULL);
 147         if (!NT_STATUS_IS_OK(status)) {
 148                 return NULL;
 149         }
 150
 151         return result;
 152 }
 153
 154 /* IRIX version */
 155
 156 int init(void)
 157 {
 158         nsd_logprintf(NSD_LOG_MIN, "entering init (wins)\n");
 159         nss_wins_init();
 160         return NSD_OK;
 161 }
 162
 163 int lookup(nsd_file_t *rq)
 164 {
 165         char *map;
 166         char *key;
 167         char *addr;
 168         struct in_addr *ip_list;
 169         struct node_status *status;
 170         int i, count, len, size;
 171         char response[1024];
 172         bool found = False;
 173
 174         nsd_logprintf(NSD_LOG_MIN, "entering lookup (wins)\n");
 175         if (! rq)
 176                 return NSD_ERROR;
 177
 178         map = nsd_attr_fetch_string(rq->f_attrs, "table", (char*)0);
 179         if (! map) {
 180                 rq->f_status = NS_FATAL;
 181                 return NSD_ERROR;
 182         }
 183
 184         key = nsd_attr_fetch_string(rq->f_attrs, "key", (char*)0);
 185         if (! key || ! *key) {
 186                 rq->f_status = NS_FATAL;
 187                 return NSD_ERROR;
 188         }
 189
 190         response[0] = '\0';
 191         len = sizeof(response) - 2;
 192
 193         /*
 194          * response needs to be a string of the following format
 195          * ip_address[ ip_address]*\tname[ alias]*
 196          */
 197         if (strcasecmp_m(map,"hosts.byaddr") == 0) {
 198                 if ( status = lookup_byaddr_backend(key, &count)) {
 199                     size = strlen(key) + 1;
 200                     if (size > len) {
 201                         talloc_free(status);
 202                         return NSD_ERROR;
 203                     }
 204                     len -= size;
 205                     strncat(response,key,size);
 206                     strncat(response,"\t",1);
 207                     for (i = 0; i < count; i++) {
 208                         /* ignore group names */
 209                         if (status[i].flags & 0x80) continue;
 210                         if (status[i].type == 0x20) {
 211                                 size = sizeof(status[i].name) + 1;
 212                                 if (size > len) {
 213                                     talloc_free(status);
 214                                     return NSD_ERROR;
 215                                 }
 216                                 len -= size;
 217                                 strncat(response, status[i].name, size);
 218                                 strncat(response, " ", 1);
 219                                 found = True;
 220                         }
 221                     }
 222                     response[strlen(response)-1] = '\n';
 223                     talloc_free(status);
 224                 }
 225         } else if (strcasecmp_m(map,"hosts.byname") == 0) {
 226             if (ip_list = lookup_byname_backend(key, &count)) {
 227                 for (i = count; i ; i--) {
 228                     addr = inet_ntoa(ip_list[i-1]);
 229                     size = strlen(addr) + 1;
 230                     if (size > len) {
 231                         free(ip_list);
 232                         return NSD_ERROR;
 233                     }
 234                     len -= size;
 235                     if (i != 0)
 236                         response[strlen(response)-1] = ' ';
 237                     strncat(response,addr,size);
 238                     strncat(response,"\t",1);
 239                 }
 240                 size = strlen(key) + 1;
 241                 if (size > len) {
 242                     free(ip_list);
 243                     return NSD_ERROR;
 244                 }
 245                 strncat(response,key,size);
 246                 strncat(response,"\n",1);
 247                 found = True;
 248                 free(ip_list);
 249             }
 250         }
 251
 252         if (found) {
 253             nsd_logprintf(NSD_LOG_LOW, "lookup (wins %s) %s\n",map,response);
 254             nsd_set_result(rq,NS_SUCCESS,response,strlen(response),VOLATILE);
 255             return NSD_OK;
 256         }
 257         nsd_logprintf(NSD_LOG_LOW, "lookup (wins) not found\n");
 258         rq->f_status = NS_NOTFOUND;
 259         return NSD_NEXT;
 260 }
 261
 262 #else
 263
 264 /* Allocate some space from the nss static buffer.  The buffer and buflen
 265    are the pointers passed in by the C library to the _nss_*_*
 266    functions. */
 267
 268 static char *get_static(char **buffer, size_t *buflen, int len)
 269 {
 270         char *result;
 271
 272         /* Error check.  We return false if things aren't set up right, or
 273            there isn't enough buffer space left. */
 274
 275         if ((buffer == NULL) || (buflen == NULL) || (*buflen < len)) {
 276                 return NULL;
 277         }
 278
 279         /* Return an index into the static buffer */
 280
 281         result = *buffer;
 282         *buffer += len;
 283         *buflen -= len;
 284
 285         return result;
 286 }
 287
 288 /****************************************************************************
 289 gethostbyname() - we ignore any domain portion of the name and only
 290 handle names that are at most 15 characters long
 291   **************************************************************************/
 292 NSS_STATUS
 293 _nss_wins_gethostbyname_r(const char *hostname, struct hostent *he,
 294                           char *buffer, size_t buflen, int *h_errnop)
 295 {
 296         NSS_STATUS nss_status = NSS_STATUS_SUCCESS;
 297         struct in_addr *ip_list;
 298         int i, count;
 299         fstring name;
 300         size_t namelen;
 301         TALLOC_CTX *frame;
 302
 303 #if HAVE_PTHREAD
 304         pthread_mutex_lock(&wins_nss_mutex);
 305 #endif
 306
 307         frame = talloc_stackframe();
 308
 309         memset(he, '\0', sizeof(*he));
 310         fstrcpy(name, hostname);
 311
 312         /* Do lookup */
 313
 314         ip_list = lookup_byname_backend(name, &count);
 315
 316         if (!ip_list) {
 317                 nss_status = NSS_STATUS_NOTFOUND;
 318                 goto out;
 319         }
 320
 321         /* Copy h_name */
 322
 323         namelen = strlen(name) + 1;
 324
 325         if ((he->h_name = get_static(&buffer, &buflen, namelen)) == NULL) {
 326                 free(ip_list);
 327                 nss_status = NSS_STATUS_TRYAGAIN;
 328                 goto out;
 329         }
 330
 331         memcpy(he->h_name, name, namelen);
 332
 333         /* Copy h_addr_list, align to pointer boundary first */
 334
 335         if ((i = (unsigned long)(buffer) % sizeof(char*)) != 0)
 336                 i = sizeof(char*) - i;
 337
 338         if (get_static(&buffer, &buflen, i) == NULL) {
 339                 free(ip_list);
 340                 nss_status = NSS_STATUS_TRYAGAIN;
 341                 goto out;
 342         }
 343
 344         if ((he->h_addr_list = (char **)get_static(
 345                      &buffer, &buflen, (count + 1) * sizeof(char *))) == NULL) {
 346                 free(ip_list);
 347                 nss_status = NSS_STATUS_TRYAGAIN;
 348                 goto out;
 349         }
 350
 351         for (i = 0; i < count; i++) {
 352                 if ((he->h_addr_list[i] = get_static(&buffer, &buflen,
 353                                                      INADDRSZ)) == NULL) {
 354                         free(ip_list);
 355                         nss_status = NSS_STATUS_TRYAGAIN;
 356                         goto out;
 357                 }
 358                 memcpy(he->h_addr_list[i], &ip_list[i], INADDRSZ);
 359         }
 360
 361         he->h_addr_list[count] = NULL;
 362
 363         free(ip_list);
 364
 365         /* Set h_addr_type and h_length */
 366
 367         he->h_addrtype = AF_INET;
 368         he->h_length = INADDRSZ;
 369
 370         /* Set h_aliases */
 371
 372         if ((i = (unsigned long)(buffer) % sizeof(char*)) != 0)
 373                 i = sizeof(char*) - i;
 374
 375         if (get_static(&buffer, &buflen, i) == NULL) {
 376                 nss_status = NSS_STATUS_TRYAGAIN;
 377                 goto out;
 378         }
 379
 380         if ((he->h_aliases = (char **)get_static(
 381                      &buffer, &buflen, sizeof(char *))) == NULL) {
 382                 nss_status = NSS_STATUS_TRYAGAIN;
 383                 goto out;
 384         }
 385
 386         he->h_aliases[0] = NULL;
 387
 388         nss_status = NSS_STATUS_SUCCESS;
 389
 390   out:
 391
 392         TALLOC_FREE(frame);
 393
 394 #if HAVE_PTHREAD
 395         pthread_mutex_unlock(&wins_nss_mutex);
 396 #endif
 397         return nss_status;
 398 }
 399
 400
 401 NSS_STATUS
 402 _nss_wins_gethostbyname2_r(const char *name, int af, struct hostent *he,
 403                            char *buffer, size_t buflen, int *h_errnop)
 404 {
 405         NSS_STATUS nss_status;
 406
 407         if(af!=AF_INET) {
 408                 *h_errnop = NO_DATA;
 409                 nss_status = NSS_STATUS_UNAVAIL;
 410         } else {
 411                 nss_status = _nss_wins_gethostbyname_r(
 412                                 name, he, buffer, buflen, h_errnop);
 413         }
 414         return nss_status;
 415 }
 416 #endif