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 2 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, write to the Free Software
  18    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19
  20 */
  21
  22 #include "includes.h"
  23 #ifdef HAVE_NS_API_H
  24 #undef VOLATILE
  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 extern BOOL AllowDebugChange;
  44
  45 NSS_STATUS _nss_wins_gethostbyname_r(const char *hostname, struct hostent *he,
  46                           char *buffer, size_t buflen, int *h_errnop);
  47 NSS_STATUS _nss_wins_gethostbyname2_r(const char *name, int af, struct hostent *he,
  48                            char *buffer, size_t buflen, int *h_errnop);
  49
  50 /* Use our own create socket code so we don't recurse.... */
  51
  52 static int wins_lookup_open_socket_in(void)
  53 {
  54         struct sockaddr_in sock;
  55         int val=1;
  56         int res;
  57
  58         memset((char *)&sock,'\0',sizeof(sock));
  59
  60 #ifdef HAVE_SOCK_SIN_LEN
  61         sock.sin_len = sizeof(sock);
  62 #endif
  63         sock.sin_port = 0;
  64         sock.sin_family = AF_INET;
  65         sock.sin_addr.s_addr = interpret_addr("0.0.0.0");
  66         res = socket(AF_INET, SOCK_DGRAM, 0);
  67         if (res == -1)
  68                 return -1;
  69
  70         setsockopt(res,SOL_SOCKET,SO_REUSEADDR,(char *)&val,sizeof(val));
  71 #ifdef SO_REUSEPORT
  72         setsockopt(res,SOL_SOCKET,SO_REUSEPORT,(char *)&val,sizeof(val));
  73 #endif /* SO_REUSEPORT */
  74
  75         /* now we've got a socket - we need to bind it */
  76
  77         if (bind(res, (struct sockaddr * ) &sock,sizeof(sock)) < 0) {
  78                 close(res);
  79                 return(-1);
  80         }
  81
  82         set_socket_options(res,"SO_BROADCAST");
  83
  84         return res;
  85 }
  86
  87
  88 static void nss_wins_init(void)
  89 {
  90         initialised = 1;
  91         DEBUGLEVEL = 0;
  92         AllowDebugChange = False;
  93
  94         TimeInit();
  95         setup_logging("nss_wins",False);
  96         load_case_tables();
  97         lp_load(dyn_CONFIGFILE,True,False,False,True);
  98         load_interfaces();
  99 }
 100
 101 static struct in_addr *lookup_byname_backend(const char *name, int *count)
 102 {
 103         int fd = -1;
 104         struct ip_service *address = NULL;
 105         struct in_addr *ret = NULL;
 106         int j, flags = 0;
 107
 108         if (!initialised) {
 109                 nss_wins_init();
 110         }
 111
 112         *count = 0;
 113
 114         /* always try with wins first */
 115         if (resolve_wins(name,0x00,&address,count)) {
 116                 if ( (ret = SMB_MALLOC_P(struct in_addr)) == NULL ) {
 117                         free( address );
 118                         return NULL;
 119                 }
 120                 *ret = address[0].ip;
 121                 free( address );
 122                 return ret;
 123         }
 124
 125         fd = wins_lookup_open_socket_in();
 126         if (fd == -1) {
 127                 return NULL;
 128         }
 129
 130         /* uggh, we have to broadcast to each interface in turn */
 131         for (j=iface_count() - 1;j >= 0;j--) {
 132                 struct in_addr *bcast = iface_n_bcast(j);
 133                 ret = name_query(fd,name,0x00,True,True,*bcast,count, &flags, NULL);
 134                 if (ret) break;
 135         }
 136
 137         close(fd);
 138         return ret;
 139 }
 140
 141 #ifdef HAVE_NS_API_H
 142
 143 static NODE_STATUS_STRUCT *lookup_byaddr_backend(char *addr, int *count)
 144 {
 145         int fd;
 146         struct in_addr  ip;
 147         struct nmb_name nname;
 148         NODE_STATUS_STRUCT *status;
 149
 150         if (!initialised) {
 151                 nss_wins_init();
 152         }
 153
 154         fd = wins_lookup_open_socket_in();
 155         if (fd == -1)
 156                 return NULL;
 157
 158         make_nmb_name(&nname, "*", 0);
 159         ip = *interpret_addr2(addr);
 160         status = node_status_query(fd,&nname,ip, count, NULL);
 161
 162         close(fd);
 163         return status;
 164 }
 165
 166 /* IRIX version */
 167
 168 int init(void)
 169 {
 170         nsd_logprintf(NSD_LOG_MIN, "entering init (wins)\n");
 171         nss_wins_init();
 172         return NSD_OK;
 173 }
 174
 175 int lookup(nsd_file_t *rq)
 176 {
 177         char *map;
 178         char *key;
 179         char *addr;
 180         struct in_addr *ip_list;
 181         NODE_STATUS_STRUCT *status;
 182         int i, count, len, size;
 183         char response[1024];
 184         BOOL found = False;
 185
 186         nsd_logprintf(NSD_LOG_MIN, "entering lookup (wins)\n");
 187         if (! rq)
 188                 return NSD_ERROR;
 189
 190         map = nsd_attr_fetch_string(rq->f_attrs, "table", (char*)0);
 191         if (! map) {
 192                 rq->f_status = NS_FATAL;
 193                 return NSD_ERROR;
 194         }
 195
 196         key = nsd_attr_fetch_string(rq->f_attrs, "key", (char*)0);
 197         if (! key || ! *key) {
 198                 rq->f_status = NS_FATAL;
 199                 return NSD_ERROR;
 200         }
 201
 202         response[0] = '\0';
 203         len = sizeof(response) - 2;
 204
 205         /*
 206          * response needs to be a string of the following format
 207          * ip_address[ ip_address]*\tname[ alias]*
 208          */
 209         if (StrCaseCmp(map,"hosts.byaddr") == 0) {
 210                 if ( status = lookup_byaddr_backend(key, &count)) {
 211                     size = strlen(key) + 1;
 212                     if (size > len) {
 213                         free(status);
 214                         return NSD_ERROR;
 215                     }
 216                     len -= size;
 217                     strncat(response,key,size);
 218                     strncat(response,"\t",1);
 219                     for (i = 0; i < count; i++) {
 220                         /* ignore group names */
 221                         if (status[i].flags & 0x80) continue;
 222                         if (status[i].type == 0x20) {
 223                                 size = sizeof(status[i].name) + 1;
 224                                 if (size > len) {
 225                                     free(status);
 226                                     return NSD_ERROR;
 227                                 }
 228                                 len -= size;
 229                                 strncat(response, status[i].name, size);
 230                                 strncat(response, " ", 1);
 231                                 found = True;
 232                         }
 233                     }
 234                     response[strlen(response)-1] = '\n';
 235                     free(status);
 236                 }
 237         } else if (StrCaseCmp(map,"hosts.byname") == 0) {
 238             if (ip_list = lookup_byname_backend(key, &count)) {
 239                 for (i = count; i ; i--) {
 240                     addr = inet_ntoa(ip_list[i-1]);
 241                     size = strlen(addr) + 1;
 242                     if (size > len) {
 243                         free(ip_list);
 244                         return NSD_ERROR;
 245                     }
 246                     len -= size;
 247                     if (i != 0)
 248                         response[strlen(response)-1] = ' ';
 249                     strncat(response,addr,size);
 250                     strncat(response,"\t",1);
 251                 }
 252                 size = strlen(key) + 1;
 253                 if (size > len) {
 254                     free(ip_list);
 255                     return NSD_ERROR;
 256                 }
 257                 strncat(response,key,size);
 258                 strncat(response,"\n",1);
 259                 found = True;
 260                 free(ip_list);
 261             }
 262         }
 263
 264         if (found) {
 265             nsd_logprintf(NSD_LOG_LOW, "lookup (wins %s) %s\n",map,response);
 266             nsd_set_result(rq,NS_SUCCESS,response,strlen(response),VOLATILE);
 267             return NSD_OK;
 268         }
 269         nsd_logprintf(NSD_LOG_LOW, "lookup (wins) not found\n");
 270         rq->f_status = NS_NOTFOUND;
 271         return NSD_NEXT;
 272 }
 273
 274 #else
 275
 276 /* Allocate some space from the nss static buffer.  The buffer and buflen
 277    are the pointers passed in by the C library to the _nss_*_*
 278    functions. */
 279
 280 static char *get_static(char **buffer, size_t *buflen, int len)
 281 {
 282         char *result;
 283
 284         /* Error check.  We return false if things aren't set up right, or
 285            there isn't enough buffer space left. */
 286
 287         if ((buffer == NULL) || (buflen == NULL) || (*buflen < len)) {
 288                 return NULL;
 289         }
 290
 291         /* Return an index into the static buffer */
 292
 293         result = *buffer;
 294         *buffer += len;
 295         *buflen -= len;
 296
 297         return result;
 298 }
 299
 300 /****************************************************************************
 301 gethostbyname() - we ignore any domain portion of the name and only
 302 handle names that are at most 15 characters long
 303   **************************************************************************/
 304 NSS_STATUS
 305 _nss_wins_gethostbyname_r(const char *hostname, struct hostent *he,
 306                           char *buffer, size_t buflen, int *h_errnop)
 307 {
 308         NSS_STATUS nss_status = NSS_STATUS_SUCCESS;
 309         struct in_addr *ip_list;
 310         int i, count;
 311         fstring name;
 312         size_t namelen;
 313
 314 #if HAVE_PTHREAD
 315         pthread_mutex_lock(&wins_nss_mutex);
 316 #endif
 317
 318         memset(he, '\0', sizeof(*he));
 319         fstrcpy(name, hostname);
 320
 321         /* Do lookup */
 322
 323         ip_list = lookup_byname_backend(name, &count);
 324
 325         if (!ip_list) {
 326                 nss_status = NSS_STATUS_NOTFOUND;
 327                 goto out;
 328         }
 329
 330         /* Copy h_name */
 331
 332         namelen = strlen(name) + 1;
 333
 334         if ((he->h_name = get_static(&buffer, &buflen, namelen)) == NULL) {
 335                 nss_status = NSS_STATUS_TRYAGAIN;
 336                 goto out;
 337         }
 338
 339         memcpy(he->h_name, name, namelen);
 340
 341         /* Copy h_addr_list, align to pointer boundary first */
 342
 343         if ((i = (unsigned long)(buffer) % sizeof(char*)) != 0)
 344                 i = sizeof(char*) - i;
 345
 346         if (get_static(&buffer, &buflen, i) == NULL) {
 347                 nss_status = NSS_STATUS_TRYAGAIN;
 348                 goto out;
 349         }
 350
 351         if ((he->h_addr_list = (char **)get_static(
 352                      &buffer, &buflen, (count + 1) * sizeof(char *))) == NULL) {
 353                 nss_status = NSS_STATUS_TRYAGAIN;
 354                 goto out;
 355         }
 356
 357         for (i = 0; i < count; i++) {
 358                 if ((he->h_addr_list[i] = get_static(&buffer, &buflen,
 359                                                      INADDRSZ)) == NULL) {
 360                         nss_status = NSS_STATUS_TRYAGAIN;
 361                         goto out;
 362                 }
 363                 memcpy(he->h_addr_list[i], &ip_list[i], INADDRSZ);
 364         }
 365
 366         he->h_addr_list[count] = NULL;
 367
 368         if (ip_list)
 369                 free(ip_list);
 370
 371         /* Set h_addr_type and h_length */
 372
 373         he->h_addrtype = AF_INET;
 374         he->h_length = INADDRSZ;
 375
 376         /* Set h_aliases */
 377
 378         if ((i = (unsigned long)(buffer) % sizeof(char*)) != 0)
 379                 i = sizeof(char*) - i;
 380
 381         if (get_static(&buffer, &buflen, i) == NULL) {
 382                 nss_status = NSS_STATUS_TRYAGAIN;
 383                 goto out;
 384         }
 385
 386         if ((he->h_aliases = (char **)get_static(
 387                      &buffer, &buflen, sizeof(char *))) == NULL) {
 388                 nss_status = NSS_STATUS_TRYAGAIN;
 389                 goto out;
 390         }
 391
 392         he->h_aliases[0] = NULL;
 393
 394         nss_status = NSS_STATUS_SUCCESS;
 395
 396   out:
 397
 398 #if HAVE_PTHREAD
 399         pthread_mutex_unlock(&wins_nss_mutex);
 400 #endif
 401         return nss_status;
 402 }
 403
 404
 405 NSS_STATUS
 406 _nss_wins_gethostbyname2_r(const char *name, int af, struct hostent *he,
 407                            char *buffer, size_t buflen, int *h_errnop)
 408 {
 409         NSS_STATUS nss_status;
 410
 411 #if HAVE_PTHREAD
 412         pthread_mutex_lock(&wins_nss_mutex);
 413 #endif
 414
 415         if(af!=AF_INET) {
 416                 *h_errnop = NO_DATA;
 417                 nss_status = NSS_STATUS_UNAVAIL;
 418         } else {
 419                 nss_status = _nss_wins_gethostbyname_r(
 420                                 name, he, buffer, buflen, h_errnop);
 421         }
 422 #if HAVE_PTHREAD
 423         pthread_mutex_unlock(&wins_nss_mutex);
 424 #endif
 425         return nss_status;
 426 }
 427 #endif