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_client.h"
  23 #include "nsswitch/libwbclient/wbclient.h"
  24 #include "lib/util/string_wrappers.h"
  25
  26 #ifdef HAVE_NS_API_H
  27
  28 #include <ns_daemon.h>
  29 #endif
  30
  31 #ifdef HAVE_PTHREAD_H
  32 #include <pthread.h>
  33 #endif
  34
  35 #ifdef HAVE_PTHREAD
  36 static pthread_mutex_t wins_nss_mutex = PTHREAD_MUTEX_INITIALIZER;
  37 #endif
  38
  39 #ifndef INADDRSZ
  40 #define INADDRSZ 4
  41 #endif
  42
  43 #ifndef NETDB_INTERNAL
  44 #define NETDB_INTERNAL -1
  45 #endif
  46
  47 #ifndef NETDB_SUCCESS
  48 #define NETDB_SUCCESS 0
  49 #endif
  50
  51 _PUBLIC_ON_LINUX_
  52 NSS_STATUS _nss_wins_gethostbyname_r(const char *hostname,
  53                                      struct hostent *he,
  54                                      char *buffer,
  55                                      size_t buflen,
  56                                      int *errnop,
  57                                      int *h_errnop);
  58 NSS_STATUS _nss_wins_gethostbyname2_r(const char *name,
  59                                       int af,
  60                                       struct hostent *he,
  61                                       char *buffer,
  62                                       size_t buflen,
  63                                       int *errnop,
  64                                       int *h_errnop);
  65
  66 static char *lookup_byname_backend(const char *name)
  67 {
  68         const char *p;
  69         char *ip, *ipp;
  70         size_t nbt_len;
  71         wbcErr result;
  72
  73         nbt_len = strlen(name);
  74         if (nbt_len > MAX_NETBIOSNAME_LEN - 1) {
  75                 return NULL;
  76         }
  77         p = strchr(name, '.');
  78         if (p != NULL) {
  79                 return NULL;
  80         }
  81
  82         wbcSetClientProcessName("nss_wins");
  83         result = wbcResolveWinsByName(name, &ip);
  84         if (result != WBC_ERR_SUCCESS) {
  85                 return NULL;
  86         }
  87
  88         ipp = strchr(ip, '\t');
  89         if (ipp != NULL) {
  90                 *ipp = '\0';
  91         }
  92
  93         return ip;
  94 }
  95
  96 #ifdef HAVE_NS_API_H
  97
  98 static char *lookup_byaddr_backend(const char *ip)
  99 {
 100         wbcErr result;
 101         char *name = NULL;
 102
 103         wbcSetClientProcessName("nss_wins");
 104         result = wbcResolveWinsByIP(ip, &name);
 105         if (result != WBC_ERR_SUCCESS) {
 106                 return NULL;
 107         }
 108
 109         return name;
 110 }
 111
 112 /* IRIX version */
 113
 114 int init(void)
 115 {
 116         bool ok;
 117
 118         nsd_logprintf(NSD_LOG_MIN, "entering init (wins)\n");
 119
 120         ok = nss_wins_init();
 121         if (!ok) {
 122                 return NSD_ERROR;
 123         }
 124
 125         return NSD_OK;
 126 }
 127
 128 int lookup(nsd_file_t *rq)
 129 {
 130         char *map;
 131         char *key;
 132         char *addr;
 133         int i, count, len, size;
 134         char response[1024];
 135         bool found = False;
 136
 137         nsd_logprintf(NSD_LOG_MIN, "entering lookup (wins)\n");
 138         if (! rq)
 139                 return NSD_ERROR;
 140
 141         map = nsd_attr_fetch_string(rq->f_attrs, "table", (char*)0);
 142         if (! map) {
 143                 rq->f_status = NS_FATAL;
 144                 return NSD_ERROR;
 145         }
 146
 147         key = nsd_attr_fetch_string(rq->f_attrs, "key", (char*)0);
 148         if (! key || ! *key) {
 149                 rq->f_status = NS_FATAL;
 150                 return NSD_ERROR;
 151         }
 152
 153         response[0] = '\0';
 154         len = sizeof(response) - 2;
 155
 156         /*
 157          * response needs to be a string of the following format
 158          * ip_address[ ip_address]*\tname[ alias]*
 159          */
 160         if (strcasecmp_m(map,"hosts.byaddr") == 0) {
 161                 char *name;
 162
 163                 name = lookup_byaddr_backend(key);
 164                 if (name != NULL) {
 165                         size = strlen(key) + 1;
 166                         if (size > len) {
 167                                 return NSD_ERROR;
 168                         }
 169                         len -= size;
 170                         strncat(response,key,size);
 171                         strncat(response,"\t",1);
 172
 173                         size = strlen(name) + 1;
 174                         if (size > len) {
 175                                 return NSD_ERROR;
 176                         }
 177                         len -= size;
 178                         strncat(response, name, size);
 179                         strncat(response, " ", 1);
 180                         found = True;
 181                 }
 182                 response[strlen(response)-1] = '\n';
 183         } else if (strcasecmp_m(map,"hosts.byname") == 0) {
 184                 char *ip;
 185
 186                 ip = lookup_byname_backend(key);
 187                 if (ip != NULL) {
 188                         size = strlen(ip) + 1;
 189                         if (size > len) {
 190                                 wbcFreeMemory(ip);
 191                                 return NSD_ERROR;
 192                         }
 193                         len -= size;
 194                         strncat(response,ip,size);
 195                         strncat(response,"\t",1);
 196                         size = strlen(key) + 1;
 197                         wbcFreeMemory(ip);
 198                         if (size > len) {
 199                                 return NSD_ERROR;
 200                         }
 201                         strncat(response,key,size);
 202                         strncat(response,"\n",1);
 203
 204                         found = True;
 205                 }
 206         }
 207
 208         if (found) {
 209             nsd_logprintf(NSD_LOG_LOW, "lookup (wins %s) %s\n",map,response);
 210             nsd_set_result(rq,NS_SUCCESS,response,strlen(response),VOLATILE);
 211             return NSD_OK;
 212         }
 213         nsd_logprintf(NSD_LOG_LOW, "lookup (wins) not found\n");
 214         rq->f_status = NS_NOTFOUND;
 215         return NSD_NEXT;
 216 }
 217
 218 #else
 219
 220 /* Allocate some space from the nss static buffer.  The buffer and buflen
 221    are the pointers passed in by the C library to the _nss_*_*
 222    functions. */
 223
 224 static char *get_static(char **buffer, size_t *buflen, size_t len)
 225 {
 226         char *result;
 227
 228         /* Error check.  We return false if things aren't set up right, or
 229            there isn't enough buffer space left. */
 230
 231         if ((buffer == NULL) || (buflen == NULL) || (*buflen < len)) {
 232                 return NULL;
 233         }
 234
 235         /* Return an index into the static buffer */
 236
 237         result = *buffer;
 238         *buffer += len;
 239         *buflen -= len;
 240
 241         return result;
 242 }
 243
 244 /****************************************************************************
 245 gethostbyname() - we ignore any domain portion of the name and only
 246 handle names that are at most 15 characters long
 247   **************************************************************************/
 248 _PUBLIC_ON_LINUX_
 249 NSS_STATUS
 250 _nss_wins_gethostbyname_r(const char *hostname,
 251                           struct hostent *he,
 252                           char *buffer,
 253                           size_t buflen,
 254                           int *errnop,
 255                           int *h_errnop)
 256 {
 257         NSS_STATUS nss_status = NSS_STATUS_SUCCESS;
 258         char *ip;
 259         struct in_addr in;
 260         int i;
 261         fstring name;
 262         size_t namelen;
 263         int rc;
 264
 265 #ifdef HAVE_PTHREAD
 266         pthread_mutex_lock(&wins_nss_mutex);
 267 #endif
 268
 269         memset(he, '\0', sizeof(*he));
 270         fstrcpy(name, hostname);
 271
 272         /* Do lookup */
 273
 274         ip = lookup_byname_backend(name);
 275         if (ip == NULL) {
 276                 *h_errnop = HOST_NOT_FOUND;
 277                 nss_status = NSS_STATUS_NOTFOUND;
 278                 goto out;
 279         }
 280
 281         rc = inet_pton(AF_INET, ip, &in);
 282         wbcFreeMemory(ip);
 283         if (rc == 0) {
 284                 *errnop = errno;
 285                 *h_errnop = NETDB_INTERNAL;
 286                 nss_status = NSS_STATUS_TRYAGAIN;
 287                 goto out;
 288         }
 289
 290         /* Copy h_name */
 291
 292         namelen = strlen(name) + 1;
 293
 294         if ((he->h_name = get_static(&buffer, &buflen, namelen)) == NULL) {
 295                 *errnop = EAGAIN;
 296                 *h_errnop = NETDB_INTERNAL;
 297                 nss_status = NSS_STATUS_TRYAGAIN;
 298                 goto out;
 299         }
 300
 301         memcpy(he->h_name, name, namelen);
 302
 303         /* Copy h_addr_list, align to pointer boundary first */
 304
 305         if ((i = (unsigned long)(buffer) % sizeof(char*)) != 0)
 306                 i = sizeof(char*) - i;
 307
 308         if (get_static(&buffer, &buflen, i) == NULL) {
 309                 *errnop = EAGAIN;
 310                 *h_errnop = NETDB_INTERNAL;
 311                 nss_status = NSS_STATUS_TRYAGAIN;
 312                 goto out;
 313         }
 314
 315         if ((he->h_addr_list = (char **)get_static(
 316                      &buffer, &buflen, 2 * sizeof(char *))) == NULL) {
 317                 *errnop = EAGAIN;
 318                 *h_errnop = NETDB_INTERNAL;
 319                 nss_status = NSS_STATUS_TRYAGAIN;
 320                 goto out;
 321         }
 322
 323         if ((he->h_addr_list[0] = get_static(&buffer, &buflen,
 324                                              INADDRSZ)) == NULL) {
 325                 *errnop = EAGAIN;
 326                 *h_errnop = NETDB_INTERNAL;
 327                 nss_status = NSS_STATUS_TRYAGAIN;
 328                 goto out;
 329         }
 330
 331         memcpy(he->h_addr_list[0], &in, INADDRSZ);
 332
 333         he->h_addr_list[1] = NULL;
 334
 335         /* Set h_addr_type and h_length */
 336
 337         he->h_addrtype = AF_INET;
 338         he->h_length = INADDRSZ;
 339
 340         /* Set h_aliases */
 341
 342         if ((i = (unsigned long)(buffer) % sizeof(char*)) != 0)
 343                 i = sizeof(char*) - i;
 344
 345         if (get_static(&buffer, &buflen, i) == NULL) {
 346                 *errnop = EAGAIN;
 347                 *h_errnop = NETDB_INTERNAL;
 348                 nss_status = NSS_STATUS_TRYAGAIN;
 349                 goto out;
 350         }
 351
 352         if ((he->h_aliases = (char **)get_static(
 353                      &buffer, &buflen, sizeof(char *))) == NULL) {
 354                 *errnop = EAGAIN;
 355                 *h_errnop = NETDB_INTERNAL;
 356                 nss_status = NSS_STATUS_TRYAGAIN;
 357                 goto out;
 358         }
 359
 360         he->h_aliases[0] = NULL;
 361
 362         *h_errnop = NETDB_SUCCESS;
 363         nss_status = NSS_STATUS_SUCCESS;
 364
 365   out:
 366
 367 #ifdef HAVE_PTHREAD
 368         pthread_mutex_unlock(&wins_nss_mutex);
 369 #endif
 370         return nss_status;
 371 }
 372
 373
 374 _PUBLIC_ON_LINUX_
 375 NSS_STATUS
 376 _nss_wins_gethostbyname2_r(const char *name,
 377                            int af,
 378                            struct hostent *he,
 379                            char *buffer,
 380                            size_t buflen,
 381                            int *errnop,
 382                            int *h_errnop)
 383 {
 384         NSS_STATUS nss_status;
 385
 386         if(af!=AF_INET) {
 387                 *errnop = EAFNOSUPPORT;
 388                 *h_errnop = NO_DATA;
 389                 nss_status = NSS_STATUS_UNAVAIL;
 390         } else {
 391                 nss_status = _nss_wins_gethostbyname_r(name,
 392                                                        he,
 393                                                        buffer,
 394                                                        buflen,
 395                                                        errnop,
 396                                                        h_errnop);
 397         }
 398         return nss_status;
 399 }
 400 #endif