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