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 #ifdef HAVE_NS_API_H
  23
  24 #include <ns_daemon.h>
  25 #endif
  26
  27 #if HAVE_PTHREAD_H
  28 #include <pthread.h>
  29 #endif
  30
  31 #if HAVE_PTHREAD
  32 static pthread_mutex_t wins_nss_mutex = PTHREAD_MUTEX_INITIALIZER;
  33 #endif
  34
  35 #ifndef INADDRSZ
  36 #define INADDRSZ 4
  37 #endif
  38
  39 static int initialised;
  40
  41 extern bool AllowDebugChange;
  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         DEBUGLEVEL = 0;
  96         AllowDebugChange = False;
  97
  98         TimeInit();
  99         setup_logging("nss_wins",False);
 100         load_case_tables();
 101         lp_load(get_dyn_CONFIGFILE(),True,False,False,True);
 102         load_interfaces();
 103 }
 104
 105 static struct in_addr *lookup_byname_backend(const char *name, int *count)
 106 {
 107         int fd = -1;
 108         struct ip_service *address = NULL;
 109         struct in_addr *ret = NULL;
 110         int j, flags = 0;
 111
 112         if (!initialised) {
 113                 nss_wins_init();
 114         }
 115
 116         *count = 0;
 117
 118         /* always try with wins first */
 119         if (NT_STATUS_IS_OK(resolve_wins(name,0x00,&address,count))) {
 120                 if ( (ret = SMB_MALLOC_P(struct in_addr)) == NULL ) {
 121                         free( address );
 122                         return NULL;
 123                 }
 124                 if (address[0].ss.ss_family != AF_INET) {
 125                         free(address);
 126                         free(ret);
 127                         return NULL;
 128                 }
 129                 *ret = ((struct sockaddr_in *)&address[0].ss)->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                 if (!bcast) {
 145                         continue;
 146                 }
 147                 in_addr_to_sockaddr_storage(&ss, *bcast);
 148                 pss = name_query(fd,name,0x00,True,True,&ss,count, &flags, NULL);
 149                 if (pss) {
 150                         if ((ret = SMB_MALLOC_P(struct in_addr)) == NULL) {
 151                                 return NULL;
 152                         }
 153                         *ret = ((struct sockaddr_in *)pss)->sin_addr;
 154                         break;
 155                 }
 156         }
 157
 158         close(fd);
 159         return ret;
 160 }
 161
 162 #ifdef HAVE_NS_API_H
 163
 164 static NODE_STATUS_STRUCT *lookup_byaddr_backend(char *addr, int *count)
 165 {
 166         int fd;
 167         struct sockaddr_storage ss;
 168         struct nmb_name nname;
 169         NODE_STATUS_STRUCT *status;
 170
 171         if (!initialised) {
 172                 nss_wins_init();
 173         }
 174
 175         fd = wins_lookup_open_socket_in();
 176         if (fd == -1)
 177                 return NULL;
 178
 179         make_nmb_name(&nname, "*", 0);
 180         if (!interpret_string_addr(&ss, addr, AI_NUMERICHOST)) {
 181                 return NULL;
 182         }
 183         status = node_status_query(fd, &nname, &ss, count, NULL);
 184
 185         close(fd);
 186         return status;
 187 }
 188
 189 /* IRIX version */
 190
 191 int init(void)
 192 {
 193         nsd_logprintf(NSD_LOG_MIN, "entering init (wins)\n");
 194         nss_wins_init();
 195         return NSD_OK;
 196 }
 197
 198 int lookup(nsd_file_t *rq)
 199 {
 200         char *map;
 201         char *key;
 202         char *addr;
 203         struct in_addr *ip_list;
 204         NODE_STATUS_STRUCT *status;
 205         int i, count, len, size;
 206         char response[1024];
 207         bool found = False;
 208
 209         nsd_logprintf(NSD_LOG_MIN, "entering lookup (wins)\n");
 210         if (! rq)
 211                 return NSD_ERROR;
 212
 213         map = nsd_attr_fetch_string(rq->f_attrs, "table", (char*)0);
 214         if (! map) {
 215                 rq->f_status = NS_FATAL;
 216                 return NSD_ERROR;
 217         }
 218
 219         key = nsd_attr_fetch_string(rq->f_attrs, "key", (char*)0);
 220         if (! key || ! *key) {
 221                 rq->f_status = NS_FATAL;
 222                 return NSD_ERROR;
 223         }
 224
 225         response[0] = '\0';
 226         len = sizeof(response) - 2;
 227
 228         /*
 229          * response needs to be a string of the following format
 230          * ip_address[ ip_address]*\tname[ alias]*
 231          */
 232         if (StrCaseCmp(map,"hosts.byaddr") == 0) {
 233                 if ( status = lookup_byaddr_backend(key, &count)) {
 234                     size = strlen(key) + 1;
 235                     if (size > len) {
 236                         free(status);
 237                         return NSD_ERROR;
 238                     }
 239                     len -= size;
 240                     strncat(response,key,size);
 241                     strncat(response,"\t",1);
 242                     for (i = 0; i < count; i++) {
 243                         /* ignore group names */
 244                         if (status[i].flags & 0x80) continue;
 245                         if (status[i].type == 0x20) {
 246                                 size = sizeof(status[i].name) + 1;
 247                                 if (size > len) {
 248                                     free(status);
 249                                     return NSD_ERROR;
 250                                 }
 251                                 len -= size;
 252                                 strncat(response, status[i].name, size);
 253                                 strncat(response, " ", 1);
 254                                 found = True;
 255                         }
 256                     }
 257                     response[strlen(response)-1] = '\n';
 258                     free(status);
 259                 }
 260         } else if (StrCaseCmp(map,"hosts.byname") == 0) {
 261             if (ip_list = lookup_byname_backend(key, &count)) {
 262                 for (i = count; i ; i--) {
 263                     addr = inet_ntoa(ip_list[i-1]);
 264                     size = strlen(addr) + 1;
 265                     if (size > len) {
 266                         free(ip_list);
 267                         return NSD_ERROR;
 268                     }
 269                     len -= size;
 270                     if (i != 0)
 271                         response[strlen(response)-1] = ' ';
 272                     strncat(response,addr,size);
 273                     strncat(response,"\t",1);
 274                 }
 275                 size = strlen(key) + 1;
 276                 if (size > len) {
 277                     free(ip_list);
 278                     return NSD_ERROR;
 279                 }
 280                 strncat(response,key,size);
 281                 strncat(response,"\n",1);
 282                 found = True;
 283                 free(ip_list);
 284             }
 285         }
 286
 287         if (found) {
 288             nsd_logprintf(NSD_LOG_LOW, "lookup (wins %s) %s\n",map,response);
 289             nsd_set_result(rq,NS_SUCCESS,response,strlen(response),VOLATILE);
 290             return NSD_OK;
 291         }
 292         nsd_logprintf(NSD_LOG_LOW, "lookup (wins) not found\n");
 293         rq->f_status = NS_NOTFOUND;
 294         return NSD_NEXT;
 295 }
 296
 297 #else
 298
 299 /* Allocate some space from the nss static buffer.  The buffer and buflen
 300    are the pointers passed in by the C library to the _nss_*_*
 301    functions. */
 302
 303 static char *get_static(char **buffer, size_t *buflen, int len)
 304 {
 305         char *result;
 306
 307         /* Error check.  We return false if things aren't set up right, or
 308            there isn't enough buffer space left. */
 309
 310         if ((buffer == NULL) || (buflen == NULL) || (*buflen < len)) {
 311                 return NULL;
 312         }
 313
 314         /* Return an index into the static buffer */
 315
 316         result = *buffer;
 317         *buffer += len;
 318         *buflen -= len;
 319
 320         return result;
 321 }
 322
 323 /****************************************************************************
 324 gethostbyname() - we ignore any domain portion of the name and only
 325 handle names that are at most 15 characters long
 326   **************************************************************************/
 327 NSS_STATUS
 328 _nss_wins_gethostbyname_r(const char *hostname, struct hostent *he,
 329                           char *buffer, size_t buflen, int *h_errnop)
 330 {
 331         NSS_STATUS nss_status = NSS_STATUS_SUCCESS;
 332         struct in_addr *ip_list;
 333         int i, count;
 334         fstring name;
 335         size_t namelen;
 336         TALLOC_CTX *frame;
 337
 338 #if HAVE_PTHREAD
 339         pthread_mutex_lock(&wins_nss_mutex);
 340 #endif
 341
 342         frame = talloc_stackframe();
 343
 344         memset(he, '\0', sizeof(*he));
 345         fstrcpy(name, hostname);
 346
 347         /* Do lookup */
 348
 349         ip_list = lookup_byname_backend(name, &count);
 350
 351         if (!ip_list) {
 352                 nss_status = NSS_STATUS_NOTFOUND;
 353                 goto out;
 354         }
 355
 356         /* Copy h_name */
 357
 358         namelen = strlen(name) + 1;
 359
 360         if ((he->h_name = get_static(&buffer, &buflen, namelen)) == NULL) {
 361                 free(ip_list);
 362                 nss_status = NSS_STATUS_TRYAGAIN;
 363                 goto out;
 364         }
 365
 366         memcpy(he->h_name, name, namelen);
 367
 368         /* Copy h_addr_list, align to pointer boundary first */
 369
 370         if ((i = (unsigned long)(buffer) % sizeof(char*)) != 0)
 371                 i = sizeof(char*) - i;
 372
 373         if (get_static(&buffer, &buflen, i) == NULL) {
 374                 free(ip_list);
 375                 nss_status = NSS_STATUS_TRYAGAIN;
 376                 goto out;
 377         }
 378
 379         if ((he->h_addr_list = (char **)get_static(
 380                      &buffer, &buflen, (count + 1) * sizeof(char *))) == NULL) {
 381                 free(ip_list);
 382                 nss_status = NSS_STATUS_TRYAGAIN;
 383                 goto out;
 384         }
 385
 386         for (i = 0; i < count; i++) {
 387                 if ((he->h_addr_list[i] = get_static(&buffer, &buflen,
 388                                                      INADDRSZ)) == NULL) {
 389                         free(ip_list);
 390                         nss_status = NSS_STATUS_TRYAGAIN;
 391                         goto out;
 392                 }
 393                 memcpy(he->h_addr_list[i], &ip_list[i], INADDRSZ);
 394         }
 395
 396         he->h_addr_list[count] = NULL;
 397
 398         free(ip_list);
 399
 400         /* Set h_addr_type and h_length */
 401
 402         he->h_addrtype = AF_INET;
 403         he->h_length = INADDRSZ;
 404
 405         /* Set h_aliases */
 406
 407         if ((i = (unsigned long)(buffer) % sizeof(char*)) != 0)
 408                 i = sizeof(char*) - i;
 409
 410         if (get_static(&buffer, &buflen, i) == NULL) {
 411                 nss_status = NSS_STATUS_TRYAGAIN;
 412                 goto out;
 413         }
 414
 415         if ((he->h_aliases = (char **)get_static(
 416                      &buffer, &buflen, sizeof(char *))) == NULL) {
 417                 nss_status = NSS_STATUS_TRYAGAIN;
 418                 goto out;
 419         }
 420
 421         he->h_aliases[0] = NULL;
 422
 423         nss_status = NSS_STATUS_SUCCESS;
 424
 425   out:
 426
 427         TALLOC_FREE(frame);
 428
 429 #if HAVE_PTHREAD
 430         pthread_mutex_unlock(&wins_nss_mutex);
 431 #endif
 432         return nss_status;
 433 }
 434
 435
 436 NSS_STATUS
 437 _nss_wins_gethostbyname2_r(const char *name, int af, struct hostent *he,
 438                            char *buffer, size_t buflen, int *h_errnop)
 439 {
 440         NSS_STATUS nss_status;
 441
 442         if(af!=AF_INET) {
 443                 *h_errnop = NO_DATA;
 444                 nss_status = NSS_STATUS_UNAVAIL;
 445         } else {
 446                 nss_status = _nss_wins_gethostbyname_r(
 447                                 name, he, buffer, buflen, h_errnop);
 448         }
 449         return nss_status;
 450 }
 451 #endif