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