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 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         if (setsockopt(res,SOL_SOCKET,SO_REUSEADDR,(char *)&val,sizeof(val)) != 0) {
  71                 close(res);
  72                 return -1;
  73         }
  74 #ifdef SO_REUSEPORT
  75         if (setsockopt(res,SOL_SOCKET,SO_REUSEPORT,(char *)&val,sizeof(val)) != 0) {
  76                 close(res);
  77                 return -1;
  78         }
  79 #endif /* SO_REUSEPORT */
  80
  81         /* now we've got a socket - we need to bind it */
  82
  83         if (bind(res, (struct sockaddr * ) &sock,sizeof(sock)) < 0) {
  84                 close(res);
  85                 return(-1);
  86         }
  87
  88         set_socket_options(res,"SO_BROADCAST");
  89
  90         return res;
  91 }
  92
  93
  94 static void nss_wins_init(void)
  95 {
  96         initialised = 1;
  97         DEBUGLEVEL = 0;
  98         AllowDebugChange = False;
  99
 100         TimeInit();
 101         setup_logging("nss_wins",False);
 102         load_case_tables();
 103         lp_load(get_dyn_CONFIGFILE(),True,False,False,True);
 104         load_interfaces();
 105 }
 106
 107 static struct in_addr *lookup_byname_backend(const char *name, int *count)
 108 {
 109         int fd = -1;
 110         struct ip_service *address = NULL;
 111         struct in_addr *ret = NULL;
 112         int j, flags = 0;
 113
 114         if (!initialised) {
 115                 nss_wins_init();
 116         }
 117
 118         *count = 0;
 119
 120         /* always try with wins first */
 121         if (NT_STATUS_IS_OK(resolve_wins(name,0x00,&address,count))) {
 122                 if ( (ret = SMB_MALLOC_P(struct in_addr)) == NULL ) {
 123                         free( address );
 124                         return NULL;
 125                 }
 126                 if (address[0].ss.ss_family != AF_INET) {
 127                         free(address);
 128                         free(ret);
 129                         return NULL;
 130                 }
 131                 *ret = ((struct sockaddr_in *)&address[0].ss)->sin_addr;
 132                 free( address );
 133                 return ret;
 134         }
 135
 136         fd = wins_lookup_open_socket_in();
 137         if (fd == -1) {
 138                 return NULL;
 139         }
 140
 141         /* uggh, we have to broadcast to each interface in turn */
 142         for (j=iface_count() - 1;j >= 0;j--) {
 143                 const struct in_addr *bcast = iface_n_bcast_v4(j);
 144                 struct sockaddr_storage ss;
 145                 struct sockaddr_storage *pss;
 146                 if (!bcast) {
 147                         continue;
 148                 }
 149                 in_addr_to_sockaddr_storage(&ss, *bcast);
 150                 pss = name_query(fd,name,0x00,True,True,&ss,count, &flags, NULL);
 151                 if (pss) {
 152                         if ((ret = SMB_MALLOC_P(struct in_addr)) == NULL) {
 153                                 return NULL;
 154                         }
 155                         *ret = ((struct sockaddr_in *)pss)->sin_addr;
 156                         break;
 157                 }
 158         }
 159
 160         close(fd);
 161         return ret;
 162 }
 163
 164 #ifdef HAVE_NS_API_H
 165
 166 static NODE_STATUS_STRUCT *lookup_byaddr_backend(char *addr, int *count)
 167 {
 168         int fd;
 169         struct sockaddr_storage ss;
 170         struct nmb_name nname;
 171         NODE_STATUS_STRUCT *status;
 172
 173         if (!initialised) {
 174                 nss_wins_init();
 175         }
 176
 177         fd = wins_lookup_open_socket_in();
 178         if (fd == -1)
 179                 return NULL;
 180
 181         make_nmb_name(&nname, "*", 0);
 182         if (!interpret_string_addr(&ss, addr, AI_NUMERICHOST)) {
 183                 return NULL;
 184         }
 185         status = node_status_query(fd, &nname, &ss, count, NULL);
 186
 187         close(fd);
 188         return status;
 189 }
 190
 191 /* IRIX version */
 192
 193 int init(void)
 194 {
 195         nsd_logprintf(NSD_LOG_MIN, "entering init (wins)\n");
 196         nss_wins_init();
 197         return NSD_OK;
 198 }
 199
 200 int lookup(nsd_file_t *rq)
 201 {
 202         char *map;
 203         char *key;
 204         char *addr;
 205         struct in_addr *ip_list;
 206         NODE_STATUS_STRUCT *status;
 207         int i, count, len, size;
 208         char response[1024];
 209         bool found = False;
 210
 211         nsd_logprintf(NSD_LOG_MIN, "entering lookup (wins)\n");
 212         if (! rq)
 213                 return NSD_ERROR;
 214
 215         map = nsd_attr_fetch_string(rq->f_attrs, "table", (char*)0);
 216         if (! map) {
 217                 rq->f_status = NS_FATAL;
 218                 return NSD_ERROR;
 219         }
 220
 221         key = nsd_attr_fetch_string(rq->f_attrs, "key", (char*)0);
 222         if (! key || ! *key) {
 223                 rq->f_status = NS_FATAL;
 224                 return NSD_ERROR;
 225         }
 226
 227         response[0] = '\0';
 228         len = sizeof(response) - 2;
 229
 230         /*
 231          * response needs to be a string of the following format
 232          * ip_address[ ip_address]*\tname[ alias]*
 233          */
 234         if (StrCaseCmp(map,"hosts.byaddr") == 0) {
 235                 if ( status = lookup_byaddr_backend(key, &count)) {
 236                     size = strlen(key) + 1;
 237                     if (size > len) {
 238                         free(status);
 239                         return NSD_ERROR;
 240                     }
 241                     len -= size;
 242                     strncat(response,key,size);
 243                     strncat(response,"\t",1);
 244                     for (i = 0; i < count; i++) {
 245                         /* ignore group names */
 246                         if (status[i].flags & 0x80) continue;
 247                         if (status[i].type == 0x20) {
 248                                 size = sizeof(status[i].name) + 1;
 249                                 if (size > len) {
 250                                     free(status);
 251                                     return NSD_ERROR;
 252                                 }
 253                                 len -= size;
 254                                 strncat(response, status[i].name, size);
 255                                 strncat(response, " ", 1);
 256                                 found = True;
 257                         }
 258                     }
 259                     response[strlen(response)-1] = '\n';
 260                     free(status);
 261                 }
 262         } else if (StrCaseCmp(map,"hosts.byname") == 0) {
 263             if (ip_list = lookup_byname_backend(key, &count)) {
 264                 for (i = count; i ; i--) {
 265                     addr = inet_ntoa(ip_list[i-1]);
 266                     size = strlen(addr) + 1;
 267                     if (size > len) {
 268                         free(ip_list);
 269                         return NSD_ERROR;
 270                     }
 271                     len -= size;
 272                     if (i != 0)
 273                         response[strlen(response)-1] = ' ';
 274                     strncat(response,addr,size);
 275                     strncat(response,"\t",1);
 276                 }
 277                 size = strlen(key) + 1;
 278                 if (size > len) {
 279                     free(ip_list);
 280                     return NSD_ERROR;
 281                 }
 282                 strncat(response,key,size);
 283                 strncat(response,"\n",1);
 284                 found = True;
 285                 free(ip_list);
 286             }
 287         }
 288
 289         if (found) {
 290             nsd_logprintf(NSD_LOG_LOW, "lookup (wins %s) %s\n",map,response);
 291             nsd_set_result(rq,NS_SUCCESS,response,strlen(response),VOLATILE);
 292             return NSD_OK;
 293         }
 294         nsd_logprintf(NSD_LOG_LOW, "lookup (wins) not found\n");
 295         rq->f_status = NS_NOTFOUND;
 296         return NSD_NEXT;
 297 }
 298
 299 #else
 300
 301 /* Allocate some space from the nss static buffer.  The buffer and buflen
 302    are the pointers passed in by the C library to the _nss_*_*
 303    functions. */
 304
 305 static char *get_static(char **buffer, size_t *buflen, int len)
 306 {
 307         char *result;
 308
 309         /* Error check.  We return false if things aren't set up right, or
 310            there isn't enough buffer space left. */
 311
 312         if ((buffer == NULL) || (buflen == NULL) || (*buflen < len)) {
 313                 return NULL;
 314         }
 315
 316         /* Return an index into the static buffer */
 317
 318         result = *buffer;
 319         *buffer += len;
 320         *buflen -= len;
 321
 322         return result;
 323 }
 324
 325 /****************************************************************************
 326 gethostbyname() - we ignore any domain portion of the name and only
 327 handle names that are at most 15 characters long
 328   **************************************************************************/
 329 NSS_STATUS
 330 _nss_wins_gethostbyname_r(const char *hostname, struct hostent *he,
 331                           char *buffer, size_t buflen, int *h_errnop)
 332 {
 333         NSS_STATUS nss_status = NSS_STATUS_SUCCESS;
 334         struct in_addr *ip_list;
 335         int i, count;
 336         fstring name;
 337         size_t namelen;
 338         TALLOC_CTX *frame;
 339
 340 #if HAVE_PTHREAD
 341         pthread_mutex_lock(&wins_nss_mutex);
 342 #endif
 343
 344         frame = talloc_stackframe();
 345
 346         memset(he, '\0', sizeof(*he));
 347         fstrcpy(name, hostname);
 348
 349         /* Do lookup */
 350
 351         ip_list = lookup_byname_backend(name, &count);
 352
 353         if (!ip_list) {
 354                 nss_status = NSS_STATUS_NOTFOUND;
 355                 goto out;
 356         }
 357
 358         /* Copy h_name */
 359
 360         namelen = strlen(name) + 1;
 361
 362         if ((he->h_name = get_static(&buffer, &buflen, namelen)) == NULL) {
 363                 free(ip_list);
 364                 nss_status = NSS_STATUS_TRYAGAIN;
 365                 goto out;
 366         }
 367
 368         memcpy(he->h_name, name, namelen);
 369
 370         /* Copy h_addr_list, align to pointer boundary first */
 371
 372         if ((i = (unsigned long)(buffer) % sizeof(char*)) != 0)
 373                 i = sizeof(char*) - i;
 374
 375         if (get_static(&buffer, &buflen, i) == NULL) {
 376                 free(ip_list);
 377                 nss_status = NSS_STATUS_TRYAGAIN;
 378                 goto out;
 379         }
 380
 381         if ((he->h_addr_list = (char **)get_static(
 382                      &buffer, &buflen, (count + 1) * sizeof(char *))) == NULL) {
 383                 free(ip_list);
 384                 nss_status = NSS_STATUS_TRYAGAIN;
 385                 goto out;
 386         }
 387
 388         for (i = 0; i < count; i++) {
 389                 if ((he->h_addr_list[i] = get_static(&buffer, &buflen,
 390                                                      INADDRSZ)) == NULL) {
 391                         free(ip_list);
 392                         nss_status = NSS_STATUS_TRYAGAIN;
 393                         goto out;
 394                 }
 395                 memcpy(he->h_addr_list[i], &ip_list[i], INADDRSZ);
 396         }
 397
 398         he->h_addr_list[count] = NULL;
 399
 400         free(ip_list);
 401
 402         /* Set h_addr_type and h_length */
 403
 404         he->h_addrtype = AF_INET;
 405         he->h_length = INADDRSZ;
 406
 407         /* Set h_aliases */
 408
 409         if ((i = (unsigned long)(buffer) % sizeof(char*)) != 0)
 410                 i = sizeof(char*) - i;
 411
 412         if (get_static(&buffer, &buflen, i) == NULL) {
 413                 nss_status = NSS_STATUS_TRYAGAIN;
 414                 goto out;
 415         }
 416
 417         if ((he->h_aliases = (char **)get_static(
 418                      &buffer, &buflen, sizeof(char *))) == NULL) {
 419                 nss_status = NSS_STATUS_TRYAGAIN;
 420                 goto out;
 421         }
 422
 423         he->h_aliases[0] = NULL;
 424
 425         nss_status = NSS_STATUS_SUCCESS;
 426
 427   out:
 428
 429         TALLOC_FREE(frame);
 430
 431 #if HAVE_PTHREAD
 432         pthread_mutex_unlock(&wins_nss_mutex);
 433 #endif
 434         return nss_status;
 435 }
 436
 437
 438 NSS_STATUS
 439 _nss_wins_gethostbyname2_r(const char *name, int af, struct hostent *he,
 440                            char *buffer, size_t buflen, int *h_errnop)
 441 {
 442         NSS_STATUS nss_status;
 443
 444         if(af!=AF_INET) {
 445                 *h_errnop = NO_DATA;
 446                 nss_status = NSS_STATUS_UNAVAIL;
 447         } else {
 448                 nss_status = _nss_wins_gethostbyname_r(
 449                                 name, he, buffer, buflen, h_errnop);
 450         }
 451         return nss_status;
 452 }
 453 #endif