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 #define NO_SYSLOG
  23
  24 #include "includes.h"
  25 #ifdef HAVE_NS_API_H
  26 #undef VOLATILE
  27
  28 #include <ns_daemon.h>
  29 #endif
  30
  31 #ifndef INADDRSZ
  32 #define INADDRSZ 4
  33 #endif
  34
  35 static int initialised;
  36
  37 extern BOOL AllowDebugChange;
  38
  39 /* Use our own create socket code so we don't recurse.... */
  40
  41 static int wins_lookup_open_socket_in(void)
  42 {
  43         struct sockaddr_in sock;
  44         int val=1;
  45         int res;
  46
  47         memset((char *)&sock,'\0',sizeof(sock));
  48
  49 #ifdef HAVE_SOCK_SIN_LEN
  50         sock.sin_len = sizeof(sock);
  51 #endif
  52         sock.sin_port = 0;
  53         sock.sin_family = AF_INET;
  54         sock.sin_addr.s_addr = interpret_addr("0.0.0.0");
  55         res = socket(AF_INET, SOCK_DGRAM, 0);
  56         if (res == -1)
  57                 return -1;
  58
  59         setsockopt(res,SOL_SOCKET,SO_REUSEADDR,(char *)&val,sizeof(val));
  60 #ifdef SO_REUSEPORT
  61         setsockopt(res,SOL_SOCKET,SO_REUSEPORT,(char *)&val,sizeof(val));
  62 #endif /* SO_REUSEPORT */
  63
  64         /* now we've got a socket - we need to bind it */
  65
  66         if (bind(res, (struct sockaddr * ) &sock,sizeof(sock)) < 0) {
  67                 close(res);
  68                 return(-1);
  69         }
  70
  71         set_socket_options(res,"SO_BROADCAST");
  72
  73         return res;
  74 }
  75
  76
  77 static void nss_wins_init(void)
  78 {
  79         initialised = 1;
  80         DEBUGLEVEL = 0;
  81         AllowDebugChange = False;
  82
  83         TimeInit();
  84         setup_logging("nss_wins",False);
  85         lp_load(dyn_CONFIGFILE,True,False,False);
  86         load_interfaces();
  87 }
  88
  89 static struct in_addr *lookup_byname_backend(const char *name, int *count)
  90 {
  91         int fd = -1;
  92         struct ip_service *address = NULL;
  93         struct in_addr *ret = NULL;
  94         int j, flags = 0;
  95
  96         if (!initialised) {
  97                 nss_wins_init();
  98         }
  99
 100         *count = 0;
 101
 102         /* always try with wins first */
 103         if (resolve_wins(name,0x00,&address,count)) {
 104                 if ( (ret = SMB_MALLOC_P(struct in_addr)) == NULL ) {
 105                         free( address );
 106                         return NULL;
 107                 }
 108                 *ret = address[0].ip;
 109                 free( address );
 110                 return ret;
 111         }
 112
 113         fd = wins_lookup_open_socket_in();
 114         if (fd == -1) {
 115                 return NULL;
 116         }
 117
 118         /* uggh, we have to broadcast to each interface in turn */
 119         for (j=iface_count() - 1;j >= 0;j--) {
 120                 struct in_addr *bcast = iface_n_bcast(j);
 121                 ret = name_query(fd,name,0x00,True,True,*bcast,count, &flags, NULL);
 122                 if (ret) break;
 123         }
 124
 125         close(fd);
 126         return ret;
 127 }
 128
 129 #ifdef HAVE_NS_API_H
 130
 131 static struct node_status *lookup_byaddr_backend(char *addr, int *count)
 132 {
 133         int fd;
 134         struct in_addr  ip;
 135         struct nmb_name nname;
 136         struct node_status *status;
 137
 138         if (!initialised) {
 139                 nss_wins_init();
 140         }
 141
 142         fd = wins_lookup_open_socket_in();
 143         if (fd == -1)
 144                 return NULL;
 145
 146         make_nmb_name(&nname, "*", 0);
 147         ip = *interpret_addr2(addr);
 148         status = node_status_query(fd,&nname,ip, count, NULL);
 149
 150         close(fd);
 151         return status;
 152 }
 153
 154 /* IRIX version */
 155
 156 int init(void)
 157 {
 158         nsd_logprintf(NSD_LOG_MIN, "entering init (wins)\n");
 159         nss_wins_init();
 160         return NSD_OK;
 161 }
 162
 163 int lookup(nsd_file_t *rq)
 164 {
 165         char *map;
 166         char *key;
 167         char *addr;
 168         struct in_addr *ip_list;
 169         struct node_status *status;
 170         int i, count, len, size;
 171         char response[1024];
 172         BOOL found = False;
 173
 174         nsd_logprintf(NSD_LOG_MIN, "entering lookup (wins)\n");
 175         if (! rq)
 176                 return NSD_ERROR;
 177
 178         map = nsd_attr_fetch_string(rq->f_attrs, "table", (char*)0);
 179         if (! map) {
 180                 rq->f_status = NS_FATAL;
 181                 return NSD_ERROR;
 182         }
 183
 184         key = nsd_attr_fetch_string(rq->f_attrs, "key", (char*)0);
 185         if (! key || ! *key) {
 186                 rq->f_status = NS_FATAL;
 187                 return NSD_ERROR;
 188         }
 189
 190         response[0] = '\0';
 191         len = sizeof(response) - 2;
 192
 193         /*
 194          * response needs to be a string of the following format
 195          * ip_address[ ip_address]*\tname[ alias]*
 196          */
 197         if (StrCaseCmp(map,"hosts.byaddr") == 0) {
 198                 if ( status = lookup_byaddr_backend(key, &count)) {
 199                     size = strlen(key) + 1;
 200                     if (size > len) {
 201                         free(status);
 202                         return NSD_ERROR;
 203                     }
 204                     len -= size;
 205                     strncat(response,key,size);
 206                     strncat(response,"\t",1);
 207                     for (i = 0; i < count; i++) {
 208                         /* ignore group names */
 209                         if (status[i].flags & 0x80) continue;
 210                         if (status[i].type == 0x20) {
 211                                 size = sizeof(status[i].name) + 1;
 212                                 if (size > len) {
 213                                     free(status);
 214                                     return NSD_ERROR;
 215                                 }
 216                                 len -= size;
 217                                 strncat(response, status[i].name, size);
 218                                 strncat(response, " ", 1);
 219                                 found = True;
 220                         }
 221                     }
 222                     response[strlen(response)-1] = '\n';
 223                     free(status);
 224                 }
 225         } else if (StrCaseCmp(map,"hosts.byname") == 0) {
 226             if (ip_list = lookup_byname_backend(key, &count)) {
 227                 for (i = count; i ; i--) {
 228                     addr = inet_ntoa(ip_list[i-1]);
 229                     size = strlen(addr) + 1;
 230                     if (size > len) {
 231                         free(ip_list);
 232                         return NSD_ERROR;
 233                     }
 234                     len -= size;
 235                     if (i != 0)
 236                         response[strlen(response)-1] = ' ';
 237                     strncat(response,addr,size);
 238                     strncat(response,"\t",1);
 239                 }
 240                 size = strlen(key) + 1;
 241                 if (size > len) {
 242                     free(ip_list);
 243                     return NSD_ERROR;
 244                 }
 245                 strncat(response,key,size);
 246                 strncat(response,"\n",1);
 247                 found = True;
 248                 free(ip_list);
 249             }
 250         }
 251
 252         if (found) {
 253             nsd_logprintf(NSD_LOG_LOW, "lookup (wins %s) %s\n",map,response);
 254             nsd_set_result(rq,NS_SUCCESS,response,strlen(response),VOLATILE);
 255             return NSD_OK;
 256         }
 257         nsd_logprintf(NSD_LOG_LOW, "lookup (wins) not found\n");
 258         rq->f_status = NS_NOTFOUND;
 259         return NSD_NEXT;
 260 }
 261
 262 #else
 263
 264 /* Allocate some space from the nss static buffer.  The buffer and buflen
 265    are the pointers passed in by the C library to the _nss_*_*
 266    functions. */
 267
 268 static char *get_static(char **buffer, size_t *buflen, int len)
 269 {
 270         char *result;
 271
 272         /* Error check.  We return false if things aren't set up right, or
 273            there isn't enough buffer space left. */
 274
 275         if ((buffer == NULL) || (buflen == NULL) || (*buflen < len)) {
 276                 return NULL;
 277         }
 278
 279         /* Return an index into the static buffer */
 280
 281         result = *buffer;
 282         *buffer += len;
 283         *buflen -= len;
 284
 285         return result;
 286 }
 287
 288 /****************************************************************************
 289 gethostbyname() - we ignore any domain portion of the name and only
 290 handle names that are at most 15 characters long
 291   **************************************************************************/
 292 NSS_STATUS
 293 _nss_wins_gethostbyname_r(const char *hostname, struct hostent *he,
 294                           char *buffer, size_t buflen, int *h_errnop)
 295 {
 296         struct in_addr *ip_list;
 297         int i, count;
 298         fstring name;
 299         size_t namelen;
 300
 301         memset(he, '\0', sizeof(*he));
 302         fstrcpy(name, hostname);
 303
 304         /* Do lookup */
 305
 306         ip_list = lookup_byname_backend(name, &count);
 307
 308         if (!ip_list)
 309                 return NSS_STATUS_NOTFOUND;
 310
 311         /* Copy h_name */
 312
 313         namelen = strlen(name) + 1;
 314
 315         if ((he->h_name = get_static(&buffer, &buflen, namelen)) == NULL)
 316                 return NSS_STATUS_TRYAGAIN;
 317
 318         memcpy(he->h_name, name, namelen);
 319
 320         /* Copy h_addr_list, align to pointer boundary first */
 321
 322         if ((i = (unsigned long)(buffer) % sizeof(char*)) != 0)
 323                 i = sizeof(char*) - i;
 324
 325         if (get_static(&buffer, &buflen, i) == NULL)
 326                 return NSS_STATUS_TRYAGAIN;
 327
 328         if ((he->h_addr_list = (char **)get_static(
 329                      &buffer, &buflen, (count + 1) * sizeof(char *))) == NULL)
 330                 return NSS_STATUS_TRYAGAIN;
 331
 332         for (i = 0; i < count; i++) {
 333                 if ((he->h_addr_list[i] = get_static(&buffer, &buflen,
 334                                                      INADDRSZ)) == NULL)
 335                         return NSS_STATUS_TRYAGAIN;
 336                 memcpy(he->h_addr_list[i], &ip_list[i], INADDRSZ);
 337         }
 338
 339         he->h_addr_list[count] = NULL;
 340
 341         if (ip_list)
 342                 free(ip_list);
 343
 344         /* Set h_addr_type and h_length */
 345
 346         he->h_addrtype = AF_INET;
 347         he->h_length = INADDRSZ;
 348
 349         /* Set h_aliases */
 350
 351         if ((i = (unsigned long)(buffer) % sizeof(char*)) != 0)
 352                 i = sizeof(char*) - i;
 353
 354         if (get_static(&buffer, &buflen, i) == NULL)
 355                 return NSS_STATUS_TRYAGAIN;
 356
 357         if ((he->h_aliases = (char **)get_static(
 358                      &buffer, &buflen, sizeof(char *))) == NULL)
 359                 return NSS_STATUS_TRYAGAIN;
 360
 361         he->h_aliases[0] = NULL;
 362
 363         return NSS_STATUS_SUCCESS;
 364 }
 365
 366
 367 NSS_STATUS
 368 _nss_wins_gethostbyname2_r(const char *name, int af, struct hostent *he,
 369                            char *buffer, size_t buflen, int *h_errnop)
 370 {
 371         if(af!=AF_INET) {
 372                 *h_errnop = NO_DATA;
 373                 return NSS_STATUS_UNAVAIL;
 374         }
 375
 376         return _nss_wins_gethostbyname_r(
 377                 name, he, buffer, buflen, h_errnop);
 378 }
 379 #endif