source/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 #undef VOLATILE
  24
  25 #include <ns_daemon.h>
  26 #endif
  27
  28 #if HAVE_PTHREAD_H
  29 #include <pthread.h>
  30 #endif
  31
  32 #if HAVE_PTHREAD
  33 static pthread_mutex_t wins_nss_mutex = PTHREAD_MUTEX_INITIALIZER;
  34 #endif
  35
  36 #ifndef INADDRSZ
  37 #define INADDRSZ 4
  38 #endif
  39
  40 static int initialised;
  41
  42 extern bool AllowDebugChange;
  43
  44 NSS_STATUS _nss_wins_gethostbyname_r(const char *hostname, struct hostent *he,
  45                           char *buffer, size_t buflen, int *h_errnop);
  46 NSS_STATUS _nss_wins_gethostbyname2_r(const char *name, int af, struct hostent *he,
  47                            char *buffer, size_t buflen, int *h_errnop);
  48
  49 /* Use our own create socket code so we don't recurse.... */
  50
  51 static int wins_lookup_open_socket_in(void)
  52 {
  53         struct sockaddr_in sock;
  54         int val=1;
  55         int res;
  56
  57         memset((char *)&sock,'\0',sizeof(sock));
  58
  59 #ifdef HAVE_SOCK_SIN_LEN
  60         sock.sin_len = sizeof(sock);
  61 #endif
  62         sock.sin_port = 0;
  63         sock.sin_family = AF_INET;
  64         sock.sin_addr.s_addr = interpret_addr("0.0.0.0");
  65         res = socket(AF_INET, SOCK_DGRAM, 0);
  66         if (res == -1)
  67                 return -1;
  68
  69         if (setsockopt(res,SOL_SOCKET,SO_REUSEADDR,(char *)&val,sizeof(val)) != 0) {
  70                 close(res);
  71                 return -1;
  72         }
  73 #ifdef SO_REUSEPORT
  74         if (setsockopt(res,SOL_SOCKET,SO_REUSEPORT,(char *)&val,sizeof(val)) != 0) {
  75                 close(res);
  76                 return -1;
  77         }
  78 #endif /* SO_REUSEPORT */
  79
  80         /* now we've got a socket - we need to bind it */
  81
  82         if (bind(res, (struct sockaddr * ) &sock,sizeof(sock)) < 0) {
  83                 close(res);
  84                 return(-1);
  85         }
  86
  87         set_socket_options(res,"SO_BROADCAST");
  88
  89         return res;
  90 }
  91
  92
  93 static void nss_wins_init(void)
  94 {
  95         initialised = 1;
  96         DEBUGLEVEL = 0;
  97         AllowDebugChange = False;
  98
  99         TimeInit();
 100         setup_logging("nss_wins",False);
 101         load_case_tables();
 102         lp_load(get_dyn_CONFIGFILE(),True,False,False,True);
 103         load_interfaces();
 104 }
 105
 106 static struct in_addr *lookup_byname_backend(const char *name, int *count)
 107 {
 108         int fd = -1;
 109         struct ip_service *address = NULL;
 110         struct in_addr *ret = NULL;
 111         int j, flags = 0;
 112
 113         if (!initialised) {
 114                 nss_wins_init();
 115         }
 116
 117         *count = 0;
 118
 119         /* always try with wins first */
 120         if (NT_STATUS_IS_OK(resolve_wins(name,0x00,&address,count))) {
 121                 if ( (ret = SMB_MALLOC_P(struct in_addr)) == NULL ) {
 122                         free( address );
 123                         return NULL;
 124                 }
 125                 if (address[0].ss.ss_family != AF_INET) {
 126                         free(address);
 127                         free(ret);
 128                         return NULL;
 129                 }
 130                 *ret = ((struct sockaddr_in *)&address[0].ss)->sin_addr;
 131                 free( address );
 132                 return ret;
 133         }
 134
 135         fd = wins_lookup_open_socket_in();
 136         if (fd == -1) {
 137                 return NULL;
 138         }
 139
 140         /* uggh, we have to broadcast to each interface in turn */
 141         for (j=iface_count() - 1;j >= 0;j--) {
 142                 const struct in_addr *bcast = iface_n_bcast_v4(j);
 143                 struct sockaddr_storage ss;
 144                 struct sockaddr_storage *pss;
 145                 if (!bcast) {
 146                         continue;
 147                 }
 148                 in_addr_to_sockaddr_storage(&ss, *bcast);
 149                 pss = name_query(fd,name,0x00,True,True,&ss,count, &flags, NULL);
 150                 if (pss) {
 151                         if ((ret = SMB_MALLOC_P(struct in_addr)) == NULL) {
 152                                 return NULL;
 153                         }
 154                         *ret = ((struct sockaddr_in *)pss)->sin_addr;
 155                         break;
 156                 }
 157         }
 158
 159         close(fd);
 160         return ret;
 161 }
 162
 163 #ifdef HAVE_NS_API_H
 164
 165 static NODE_STATUS_STRUCT *lookup_byaddr_backend(char *addr, int *count)
 166 {
 167         int fd;
 168         struct sockaddr_storage ss;
 169         struct nmb_name nname;
 170         NODE_STATUS_STRUCT *status;
 171
 172         if (!initialised) {
 173                 nss_wins_init();
 174         }
 175
 176         fd = wins_lookup_open_socket_in();
 177         if (fd == -1)
 178                 return NULL;
 179
 180         make_nmb_name(&nname, "*", 0);
 181         if (!interpret_string_addr(&ss, addr, AI_NUMERICHOST)) {
 182                 return NULL;
 183         }
 184         status = node_status_query(fd, &nname, &ss, count, NULL);
 185
 186         close(fd);
 187         return status;
 188 }
 189
 190 /* IRIX version */
 191
 192 int init(void)
 193 {
 194         nsd_logprintf(NSD_LOG_MIN, "entering init (wins)\n");
 195         nss_wins_init();
 196         return NSD_OK;
 197 }
 198
 199 int lookup(nsd_file_t *rq)
 200 {
 201         char *map;
 202         char *key;
 203         char *addr;
 204         struct in_addr *ip_list;
 205         NODE_STATUS_STRUCT *status;
 206         int i, count, len, size;
 207         char response[1024];
 208         bool found = False;
 209
 210         nsd_logprintf(NSD_LOG_MIN, "entering lookup (wins)\n");
 211         if (! rq)
 212                 return NSD_ERROR;
 213
 214         map = nsd_attr_fetch_string(rq->f_attrs, "table", (char*)0);
 215         if (! map) {
 216                 rq->f_status = NS_FATAL;
 217                 return NSD_ERROR;
 218         }
 219
 220         key = nsd_attr_fetch_string(rq->f_attrs, "key", (char*)0);
 221         if (! key || ! *key) {
 222                 rq->f_status = NS_FATAL;
 223                 return NSD_ERROR;
 224         }
 225
 226         response[0] = '\0';
 227         len = sizeof(response) - 2;
 228
 229         /*
 230          * response needs to be a string of the following format
 231          * ip_address[ ip_address]*\tname[ alias]*
 232          */
 233         if (StrCaseCmp(map,"hosts.byaddr") == 0) {
 234                 if ( status = lookup_byaddr_backend(key, &count)) {
 235                     size = strlen(key) + 1;
 236                     if (size > len) {
 237                         free(status);
 238                         return NSD_ERROR;
 239                     }
 240                     len -= size;
 241                     strncat(response,key,size);
 242                     strncat(response,"\t",1);
 243                     for (i = 0; i < count; i++) {
 244                         /* ignore group names */
 245                         if (status[i].flags & 0x80) continue;
 246                         if (status[i].type == 0x20) {
 247                                 size = sizeof(status[i].name) + 1;
 248                                 if (size > len) {
 249                                     free(status);
 250                                     return NSD_ERROR;
 251                                 }
 252                                 len -= size;
 253                                 strncat(response, status[i].name, size);
 254                                 strncat(response, " ", 1);
 255                                 found = True;
 256                         }
 257                     }
 258                     response[strlen(response)-1] = '\n';
 259                     free(status);
 260                 }
 261         } else if (StrCaseCmp(map,"hosts.byname") == 0) {
 262             if (ip_list = lookup_byname_backend(key, &count)) {
 263                 for (i = count; i ; i--) {
 264                     addr = inet_ntoa(ip_list[i-1]);
 265                     size = strlen(addr) + 1;
 266                     if (size > len) {
 267                         free(ip_list);
 268                         return NSD_ERROR;
 269                     }
 270                     len -= size;
 271                     if (i != 0)
 272                         response[strlen(response)-1] = ' ';
 273                     strncat(response,addr,size);
 274                     strncat(response,"\t",1);
 275                 }
 276                 size = strlen(key) + 1;
 277                 if (size > len) {
 278                     free(ip_list);
 279                     return NSD_ERROR;
 280                 }
 281                 strncat(response,key,size);
 282                 strncat(response,"\n",1);
 283                 found = True;
 284                 free(ip_list);
 285             }
 286         }
 287
 288         if (found) {
 289             nsd_logprintf(NSD_LOG_LOW, "lookup (wins %s) %s\n",map,response);
 290             nsd_set_result(rq,NS_SUCCESS,response,strlen(response),VOLATILE);
 291             return NSD_OK;
 292         }
 293         nsd_logprintf(NSD_LOG_LOW, "lookup (wins) not found\n");
 294         rq->f_status = NS_NOTFOUND;
 295         return NSD_NEXT;
 296 }
 297
 298 #else
 299
 300 /* Allocate some space from the nss static buffer.  The buffer and buflen
 301    are the pointers passed in by the C library to the _nss_*_*
 302    functions. */
 303
 304 static char *get_static(char **buffer, size_t *buflen, int len)
 305 {
 306         char *result;
 307
 308         /* Error check.  We return false if things aren't set up right, or
 309            there isn't enough buffer space left. */
 310
 311         if ((buffer == NULL) || (buflen == NULL) || (*buflen < len)) {
 312                 return NULL;
 313         }
 314
 315         /* Return an index into the static buffer */
 316
 317         result = *buffer;
 318         *buffer += len;
 319         *buflen -= len;
 320
 321         return result;
 322 }
 323
 324 /****************************************************************************
 325 gethostbyname() - we ignore any domain portion of the name and only
 326 handle names that are at most 15 characters long
 327   **************************************************************************/
 328 NSS_STATUS
 329 _nss_wins_gethostbyname_r(const char *hostname, struct hostent *he,
 330                           char *buffer, size_t buflen, int *h_errnop)
 331 {
 332         NSS_STATUS nss_status = NSS_STATUS_SUCCESS;
 333         struct in_addr *ip_list;
 334         int i, count;
 335         fstring name;
 336         size_t namelen;
 337
 338 #if HAVE_PTHREAD
 339         pthread_mutex_lock(&wins_nss_mutex);
 340 #endif
 341
 342         memset(he, '\0', sizeof(*he));
 343         fstrcpy(name, hostname);
 344
 345         /* Do lookup */
 346
 347         ip_list = lookup_byname_backend(name, &count);
 348
 349         if (!ip_list) {
 350                 nss_status = NSS_STATUS_NOTFOUND;
 351                 goto out;
 352         }
 353
 354         /* Copy h_name */
 355
 356         namelen = strlen(name) + 1;
 357
 358         if ((he->h_name = get_static(&buffer, &buflen, namelen)) == NULL) {
 359                 free(ip_list);
 360                 nss_status = NSS_STATUS_TRYAGAIN;
 361                 goto out;
 362         }
 363
 364         memcpy(he->h_name, name, namelen);
 365
 366         /* Copy h_addr_list, align to pointer boundary first */
 367
 368         if ((i = (unsigned long)(buffer) % sizeof(char*)) != 0)
 369                 i = sizeof(char*) - i;
 370
 371         if (get_static(&buffer, &buflen, i) == NULL) {
 372                 free(ip_list);
 373                 nss_status = NSS_STATUS_TRYAGAIN;
 374                 goto out;
 375         }
 376
 377         if ((he->h_addr_list = (char **)get_static(
 378                      &buffer, &buflen, (count + 1) * sizeof(char *))) == NULL) {
 379                 free(ip_list);
 380                 nss_status = NSS_STATUS_TRYAGAIN;
 381                 goto out;
 382         }
 383
 384         for (i = 0; i < count; i++) {
 385                 if ((he->h_addr_list[i] = get_static(&buffer, &buflen,
 386                                                      INADDRSZ)) == NULL) {
 387                         free(ip_list);
 388                         nss_status = NSS_STATUS_TRYAGAIN;
 389                         goto out;
 390                 }
 391                 memcpy(he->h_addr_list[i], &ip_list[i], INADDRSZ);
 392         }
 393
 394         he->h_addr_list[count] = NULL;
 395
 396         free(ip_list);
 397
 398         /* Set h_addr_type and h_length */
 399
 400         he->h_addrtype = AF_INET;
 401         he->h_length = INADDRSZ;
 402
 403         /* Set h_aliases */
 404
 405         if ((i = (unsigned long)(buffer) % sizeof(char*)) != 0)
 406                 i = sizeof(char*) - i;
 407
 408         if (get_static(&buffer, &buflen, i) == NULL) {
 409                 nss_status = NSS_STATUS_TRYAGAIN;
 410                 goto out;
 411         }
 412
 413         if ((he->h_aliases = (char **)get_static(
 414                      &buffer, &buflen, sizeof(char *))) == NULL) {
 415                 nss_status = NSS_STATUS_TRYAGAIN;
 416                 goto out;
 417         }
 418
 419         he->h_aliases[0] = NULL;
 420
 421         nss_status = NSS_STATUS_SUCCESS;
 422
 423   out:
 424
 425 #if HAVE_PTHREAD
 426         pthread_mutex_unlock(&wins_nss_mutex);
 427 #endif
 428         return nss_status;
 429 }
 430
 431
 432 NSS_STATUS
 433 _nss_wins_gethostbyname2_r(const char *name, int af, struct hostent *he,
 434                            char *buffer, size_t buflen, int *h_errnop)
 435 {
 436         NSS_STATUS nss_status;
 437
 438         if(af!=AF_INET) {
 439                 *h_errnop = NO_DATA;
 440                 nss_status = NSS_STATUS_UNAVAIL;
 441         } else {
 442                 nss_status = _nss_wins_gethostbyname_r(
 443                                 name, he, buffer, buflen, h_errnop);
 444         }
 445         return nss_status;
 446 }
 447 #endif