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