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