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