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