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 /* Use our own create socket code so we don't recurse.... */
  49
  50 static int wins_lookup_open_socket_in(void)
  51 {
  52         struct sockaddr_in sock;
  53         int val=1;
  54         int res;
  55
  56         memset((char *)&sock,'\0',sizeof(sock));
  57
  58 #ifdef HAVE_SOCK_SIN_LEN
  59         sock.sin_len = sizeof(sock);
  60 #endif
  61         sock.sin_port = 0;
  62         sock.sin_family = AF_INET;
  63         sock.sin_addr.s_addr = interpret_addr("0.0.0.0");
  64         res = socket(AF_INET, SOCK_DGRAM, 0);
  65         if (res == -1)
  66                 return -1;
  67
  68         if (setsockopt(res,SOL_SOCKET,SO_REUSEADDR,(char *)&val,sizeof(val)) != 0) {
  69                 close(res);
  70                 return -1;
  71         }
  72 #ifdef SO_REUSEPORT
  73         if (setsockopt(res,SOL_SOCKET,SO_REUSEPORT,(char *)&val,sizeof(val)) != 0) {
  74                 close(res);
  75                 return -1;
  76         }
  77 #endif /* SO_REUSEPORT */
  78
  79         /* now we've got a socket - we need to bind it */
  80
  81         if (bind(res, (struct sockaddr * ) &sock,sizeof(sock)) < 0) {
  82                 close(res);
  83                 return(-1);
  84         }
  85
  86         set_socket_options(res,"SO_BROADCAST");
  87
  88         return res;
  89 }
  90
  91
  92 static void nss_wins_init(void)
  93 {
  94         initialised = 1;
  95         load_case_tables();
  96         lp_set_cmdline("log level", "0");
  97
  98         TimeInit();
  99         setup_logging("nss_wins",False);
 100         lp_load(get_dyn_CONFIGFILE(),True,False,False,True);
 101         load_interfaces();
 102 }
 103
 104 static struct in_addr *lookup_byname_backend(const char *name, int *count)
 105 {
 106         int fd = -1;
 107         struct ip_service *address = NULL;
 108         struct in_addr *ret = NULL;
 109         int j, flags = 0;
 110
 111         if (!initialised) {
 112                 nss_wins_init();
 113         }
 114
 115         *count = 0;
 116
 117         /* always try with wins first */
 118         if (NT_STATUS_IS_OK(resolve_wins(name,0x00,&address,count))) {
 119                 if ( (ret = SMB_MALLOC_P(struct in_addr)) == NULL ) {
 120                         free( address );
 121                         return NULL;
 122                 }
 123                 if (address[0].ss.ss_family != AF_INET) {
 124                         free(address);
 125                         free(ret);
 126                         return NULL;
 127                 }
 128                 *ret = ((struct sockaddr_in *)(void *)&address[0].ss)
 129                         ->sin_addr;
 130                 free( address );
 131                 return ret;
 132         }
 133
 134         fd = wins_lookup_open_socket_in();
 135         if (fd == -1) {
 136                 return NULL;
 137         }
 138
 139         /* uggh, we have to broadcast to each interface in turn */
 140         for (j=iface_count() - 1;j >= 0;j--) {
 141                 const struct in_addr *bcast = iface_n_bcast_v4(j);
 142                 struct sockaddr_storage ss;
 143                 struct sockaddr_storage *pss;
 144                 NTSTATUS status;
 145
 146                 if (!bcast) {
 147                         continue;
 148                 }
 149                 in_addr_to_sockaddr_storage(&ss, *bcast);
 150                 status = name_query(fd, name, 0x00, True, True, &ss,
 151                                     NULL, &pss, count, &flags, NULL);
 152                 if (pss) {
 153                         if ((ret = SMB_MALLOC_P(struct in_addr)) == NULL) {
 154                                 return NULL;
 155                         }
 156                         *ret = ((struct sockaddr_in *)pss)->sin_addr;
 157                         TALLOC_FREE(pss);
 158                         break;
 159                 }
 160         }
 161
 162         close(fd);
 163         return ret;
 164 }
 165
 166 #ifdef HAVE_NS_API_H
 167
 168 static struct node_status *lookup_byaddr_backend(char *addr, int *count)
 169 {
 170         int fd;
 171         struct sockaddr_storage ss;
 172         struct nmb_name nname;
 173         struct node_status *status;
 174
 175         if (!initialised) {
 176                 nss_wins_init();
 177         }
 178
 179         fd = wins_lookup_open_socket_in();
 180         if (fd == -1)
 181                 return NULL;
 182
 183         make_nmb_name(&nname, "*", 0);
 184         if (!interpret_string_addr(&ss, addr, AI_NUMERICHOST)) {
 185                 return NULL;
 186         }
 187         status = node_status_query(fd, &nname, &ss, count, NULL);
 188
 189         close(fd);
 190         return status;
 191 }
 192
 193 /* IRIX version */
 194
 195 int init(void)
 196 {
 197         nsd_logprintf(NSD_LOG_MIN, "entering init (wins)\n");
 198         nss_wins_init();
 199         return NSD_OK;
 200 }
 201
 202 int lookup(nsd_file_t *rq)
 203 {
 204         char *map;
 205         char *key;
 206         char *addr;
 207         struct in_addr *ip_list;
 208         struct node_status *status;
 209         int i, count, len, size;
 210         char response[1024];
 211         bool found = False;
 212
 213         nsd_logprintf(NSD_LOG_MIN, "entering lookup (wins)\n");
 214         if (! rq)
 215                 return NSD_ERROR;
 216
 217         map = nsd_attr_fetch_string(rq->f_attrs, "table", (char*)0);
 218         if (! map) {
 219                 rq->f_status = NS_FATAL;
 220                 return NSD_ERROR;
 221         }
 222
 223         key = nsd_attr_fetch_string(rq->f_attrs, "key", (char*)0);
 224         if (! key || ! *key) {
 225                 rq->f_status = NS_FATAL;
 226                 return NSD_ERROR;
 227         }
 228
 229         response[0] = '\0';
 230         len = sizeof(response) - 2;
 231
 232         /*
 233          * response needs to be a string of the following format
 234          * ip_address[ ip_address]*\tname[ alias]*
 235          */
 236         if (StrCaseCmp(map,"hosts.byaddr") == 0) {
 237                 if ( status = lookup_byaddr_backend(key, &count)) {
 238                     size = strlen(key) + 1;
 239                     if (size > len) {
 240                         free(status);
 241                         return NSD_ERROR;
 242                     }
 243                     len -= size;
 244                     strncat(response,key,size);
 245                     strncat(response,"\t",1);
 246                     for (i = 0; i < count; i++) {
 247                         /* ignore group names */
 248                         if (status[i].flags & 0x80) continue;
 249                         if (status[i].type == 0x20) {
 250                                 size = sizeof(status[i].name) + 1;
 251                                 if (size > len) {
 252                                     free(status);
 253                                     return NSD_ERROR;
 254                                 }
 255                                 len -= size;
 256                                 strncat(response, status[i].name, size);
 257                                 strncat(response, " ", 1);
 258                                 found = True;
 259                         }
 260                     }
 261                     response[strlen(response)-1] = '\n';
 262                     free(status);
 263                 }
 264         } else if (StrCaseCmp(map,"hosts.byname") == 0) {
 265             if (ip_list = lookup_byname_backend(key, &count)) {
 266                 for (i = count; i ; i--) {
 267                     addr = inet_ntoa(ip_list[i-1]);
 268                     size = strlen(addr) + 1;
 269                     if (size > len) {
 270                         free(ip_list);
 271                         return NSD_ERROR;
 272                     }
 273                     len -= size;
 274                     if (i != 0)
 275                         response[strlen(response)-1] = ' ';
 276                     strncat(response,addr,size);
 277                     strncat(response,"\t",1);
 278                 }
 279                 size = strlen(key) + 1;
 280                 if (size > len) {
 281                     free(ip_list);
 282                     return NSD_ERROR;
 283                 }
 284                 strncat(response,key,size);
 285                 strncat(response,"\n",1);
 286                 found = True;
 287                 free(ip_list);
 288             }
 289         }
 290
 291         if (found) {
 292             nsd_logprintf(NSD_LOG_LOW, "lookup (wins %s) %s\n",map,response);
 293             nsd_set_result(rq,NS_SUCCESS,response,strlen(response),VOLATILE);
 294             return NSD_OK;
 295         }
 296         nsd_logprintf(NSD_LOG_LOW, "lookup (wins) not found\n");
 297         rq->f_status = NS_NOTFOUND;
 298         return NSD_NEXT;
 299 }
 300
 301 #else
 302
 303 /* Allocate some space from the nss static buffer.  The buffer and buflen
 304    are the pointers passed in by the C library to the _nss_*_*
 305    functions. */
 306
 307 static char *get_static(char **buffer, size_t *buflen, int len)
 308 {
 309         char *result;
 310
 311         /* Error check.  We return false if things aren't set up right, or
 312            there isn't enough buffer space left. */
 313
 314         if ((buffer == NULL) || (buflen == NULL) || (*buflen < len)) {
 315                 return NULL;
 316         }
 317
 318         /* Return an index into the static buffer */
 319
 320         result = *buffer;
 321         *buffer += len;
 322         *buflen -= len;
 323
 324         return result;
 325 }
 326
 327 /****************************************************************************
 328 gethostbyname() - we ignore any domain portion of the name and only
 329 handle names that are at most 15 characters long
 330   **************************************************************************/
 331 NSS_STATUS
 332 _nss_wins_gethostbyname_r(const char *hostname, struct hostent *he,
 333                           char *buffer, size_t buflen, int *h_errnop)
 334 {
 335         NSS_STATUS nss_status = NSS_STATUS_SUCCESS;
 336         struct in_addr *ip_list;
 337         int i, count;
 338         fstring name;
 339         size_t namelen;
 340         TALLOC_CTX *frame;
 341
 342 #if HAVE_PTHREAD
 343         pthread_mutex_lock(&wins_nss_mutex);
 344 #endif
 345
 346         frame = talloc_stackframe();
 347
 348         memset(he, '\0', sizeof(*he));
 349         fstrcpy(name, hostname);
 350
 351         /* Do lookup */
 352
 353         ip_list = lookup_byname_backend(name, &count);
 354
 355         if (!ip_list) {
 356                 nss_status = NSS_STATUS_NOTFOUND;
 357                 goto out;
 358         }
 359
 360         /* Copy h_name */
 361
 362         namelen = strlen(name) + 1;
 363
 364         if ((he->h_name = get_static(&buffer, &buflen, namelen)) == NULL) {
 365                 free(ip_list);
 366                 nss_status = NSS_STATUS_TRYAGAIN;
 367                 goto out;
 368         }
 369
 370         memcpy(he->h_name, name, namelen);
 371
 372         /* Copy h_addr_list, align to pointer boundary first */
 373
 374         if ((i = (unsigned long)(buffer) % sizeof(char*)) != 0)
 375                 i = sizeof(char*) - i;
 376
 377         if (get_static(&buffer, &buflen, i) == NULL) {
 378                 free(ip_list);
 379                 nss_status = NSS_STATUS_TRYAGAIN;
 380                 goto out;
 381         }
 382
 383         if ((he->h_addr_list = (char **)get_static(
 384                      &buffer, &buflen, (count + 1) * sizeof(char *))) == NULL) {
 385                 free(ip_list);
 386                 nss_status = NSS_STATUS_TRYAGAIN;
 387                 goto out;
 388         }
 389
 390         for (i = 0; i < count; i++) {
 391                 if ((he->h_addr_list[i] = get_static(&buffer, &buflen,
 392                                                      INADDRSZ)) == NULL) {
 393                         free(ip_list);
 394                         nss_status = NSS_STATUS_TRYAGAIN;
 395                         goto out;
 396                 }
 397                 memcpy(he->h_addr_list[i], &ip_list[i], INADDRSZ);
 398         }
 399
 400         he->h_addr_list[count] = NULL;
 401
 402         free(ip_list);
 403
 404         /* Set h_addr_type and h_length */
 405
 406         he->h_addrtype = AF_INET;
 407         he->h_length = INADDRSZ;
 408
 409         /* Set h_aliases */
 410
 411         if ((i = (unsigned long)(buffer) % sizeof(char*)) != 0)
 412                 i = sizeof(char*) - i;
 413
 414         if (get_static(&buffer, &buflen, i) == NULL) {
 415                 nss_status = NSS_STATUS_TRYAGAIN;
 416                 goto out;
 417         }
 418
 419         if ((he->h_aliases = (char **)get_static(
 420                      &buffer, &buflen, sizeof(char *))) == NULL) {
 421                 nss_status = NSS_STATUS_TRYAGAIN;
 422                 goto out;
 423         }
 424
 425         he->h_aliases[0] = NULL;
 426
 427         nss_status = NSS_STATUS_SUCCESS;
 428
 429   out:
 430
 431         TALLOC_FREE(frame);
 432
 433 #if HAVE_PTHREAD
 434         pthread_mutex_unlock(&wins_nss_mutex);
 435 #endif
 436         return nss_status;
 437 }
 438
 439
 440 NSS_STATUS
 441 _nss_wins_gethostbyname2_r(const char *name, int af, struct hostent *he,
 442                            char *buffer, size_t buflen, int *h_errnop)
 443 {
 444         NSS_STATUS nss_status;
 445
 446         if(af!=AF_INET) {
 447                 *h_errnop = NO_DATA;
 448                 nss_status = NSS_STATUS_UNAVAIL;
 449         } else {
 450                 nss_status = _nss_wins_gethostbyname_r(
 451                                 name, he, buffer, buflen, h_errnop);
 452         }
 453         return nss_status;
 454 }
 455 #endif