1/* 2 Unix SMB/CIFS implementation. 3 4 NetBIOS name cache module on top of gencache mechanism. 5 6 Copyright (C) Tim Potter 2002 7 Copyright (C) Rafal Szczesniak 2002 8 9 This program is free software; you can redistribute it and/or modify 10 it under the terms of the GNU General Public License as published by 11 the Free Software Foundation; either version 2 of the License, or 12 (at your option) any later version. 13 14 This program is distributed in the hope that it will be useful, 15 but WITHOUT ANY WARRANTY; without even the implied warranty of 16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 GNU General Public License for more details. 18 19 You should have received a copy of the GNU General Public License 20 along with this program; if not, write to the Free Software 21 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 22*/ 23 24#include "includes.h" 25 26#define NBTKEY_FMT "NBT/%s#%02X" 27 28 29/** 30 * Initialise namecache system. Function calls gencache 31 * initialisation function to perform necessary actions 32 * 33 * @return true upon successful initialisation of the cache or 34 * false on failure 35 **/ 36 37BOOL namecache_enable(void) 38{ 39 /* 40 * Check if name caching disabled by setting the name cache 41 * timeout to zero. 42 */ 43 44 if (lp_name_cache_timeout() == 0) { 45 DEBUG(5, ("namecache_enable: disabling netbios name cache\n")); 46 return False; 47 } 48 49 /* Init namecache by calling gencache initialisation */ 50 51 if (!gencache_init()) { 52 DEBUG(2, ("namecache_enable: Couldn't initialise namecache on top of gencache.\n")); 53 return False; 54 } 55 56 /* I leave it for now, though I don't think we really need this (mimir, 27.09.2002) */ 57 DEBUG(5, ("namecache_enable: enabling netbios namecache, timeout %d " 58 "seconds\n", lp_name_cache_timeout())); 59 60 return True; 61} 62 63 64/** 65 * Shutdown namecache. Routine calls gencache close function 66 * to safely close gencache file. 67 * 68 * @return true upon successful shutdown of the cache or 69 * false on failure 70 **/ 71 72BOOL namecache_shutdown(void) 73{ 74 if (!gencache_shutdown()) { 75 DEBUG(2, ("namecache_shutdown: Couldn't close namecache on top of gencache.\n")); 76 return False; 77 } 78 79 DEBUG(5, ("namecache_shutdown: netbios namecache closed successfully.\n")); 80 return True; 81} 82 83 84/** 85 * Generates a key for netbios name lookups on basis of 86 * netbios name and type. 87 * The caller must free returned key string when finished. 88 * 89 * @param name netbios name string (case insensitive) 90 * @param name_type netbios type of the name being looked up 91 * 92 * @return string consisted of uppercased name and appended 93 * type number 94 */ 95 96static char* namecache_key(const char *name, int name_type) 97{ 98 char *keystr; 99 asprintf(&keystr, NBTKEY_FMT, strupper_static(name), name_type); 100 101 return keystr; 102} 103 104 105/** 106 * Store a name(s) in the name cache 107 * 108 * @param name netbios names array 109 * @param name_type integer netbios name type 110 * @param num_names number of names being stored 111 * @param ip_list array of in_addr structures containing 112 * ip addresses being stored 113 **/ 114 115BOOL namecache_store(const char *name, int name_type, 116 int num_names, struct ip_service *ip_list) 117{ 118 time_t expiry; 119 char *key, *value_string; 120 int i; 121 BOOL ret; 122 123 /* 124 * we use gecache call to avoid annoying debug messages about 125 * initialised namecache again and again... 126 */ 127 if (!gencache_init()) return False; 128 129 if (name_type > 255) { 130 return False; /* Don't store non-real name types. */ 131 } 132 133 if ( DEBUGLEVEL >= 5 ) { 134 DEBUG(5, ("namecache_store: storing %d address%s for %s#%02x: ", 135 num_names, num_names == 1 ? "": "es", name, name_type)); 136 137 for (i = 0; i < num_names; i++) 138 DEBUGADD(5, ("%s:%d%s", inet_ntoa(ip_list[i].ip), 139 ip_list[i].port, (i == (num_names - 1) ? "" : ","))); 140 141 DEBUGADD(5, ("\n")); 142 } 143 144 key = namecache_key(name, name_type); 145 if (!key) { 146 return False; 147 } 148 149 expiry = time(NULL) + lp_name_cache_timeout(); 150 151 /* 152 * Generate string representation of ip addresses list 153 * First, store the number of ip addresses and then 154 * place each single ip 155 */ 156 if (!ipstr_list_make(&value_string, ip_list, num_names)) { 157 SAFE_FREE(key); 158 SAFE_FREE(value_string); 159 return False; 160 } 161 162 /* set the entry */ 163 ret = gencache_set(key, value_string, expiry); 164 SAFE_FREE(key); 165 SAFE_FREE(value_string); 166 return ret; 167} 168 169 170/** 171 * Look up a name in the cache. 172 * 173 * @param name netbios name to look up for 174 * @param name_type netbios name type of @param name 175 * @param ip_list mallocated list of IP addresses if found in the cache, 176 * NULL otherwise 177 * @param num_names number of entries found 178 * 179 * @return true upon successful fetch or 180 * false if name isn't found in the cache or has expired 181 **/ 182 183BOOL namecache_fetch(const char *name, int name_type, struct ip_service **ip_list, 184 int *num_names) 185{ 186 char *key, *value; 187 time_t timeout; 188 189 /* exit now if null pointers were passed as they're required further */ 190 if (!ip_list || !num_names) return False; 191 192 if (!gencache_init()) 193 return False; 194 195 if (name_type > 255) { 196 return False; /* Don't fetch non-real name types. */ 197 } 198 199 *num_names = 0; 200 201 /* 202 * Use gencache interface - lookup the key 203 */ 204 key = namecache_key(name, name_type); 205 if (!key) { 206 return False; 207 } 208 209 if (!gencache_get(key, &value, &timeout)) { 210 DEBUG(5, ("no entry for %s#%02X found.\n", name, name_type)); 211 SAFE_FREE(key); 212 return False; 213 } else { 214 DEBUG(5, ("name %s#%02X found.\n", name, name_type)); 215 } 216 217 /* 218 * Split up the stored value into the list of IP adresses 219 */ 220 *num_names = ipstr_list_parse(value, ip_list); 221 222 SAFE_FREE(key); 223 SAFE_FREE(value); 224 225 return *num_names > 0; /* true only if some ip has been fetched */ 226} 227 228/** 229 * Remove a namecache entry. Needed for site support. 230 * 231 **/ 232 233BOOL namecache_delete(const char *name, int name_type) 234{ 235 BOOL ret; 236 char *key; 237 238 if (!gencache_init()) 239 return False; 240 241 if (name_type > 255) { 242 return False; /* Don't fetch non-real name types. */ 243 } 244 245 key = namecache_key(name, name_type); 246 if (!key) { 247 return False; 248 } 249 ret = gencache_del(key); 250 SAFE_FREE(key); 251 return ret; 252} 253 254/** 255 * Delete single namecache entry. Look at the 256 * gencache_iterate definition. 257 * 258 **/ 259 260static void flush_netbios_name(const char* key, const char *value, time_t timeout, void* dptr) 261{ 262 gencache_del(key); 263 DEBUG(5, ("Deleting entry %s\n", key)); 264} 265 266 267/** 268 * Flush all names from the name cache. 269 * It's done by gencache_iterate() 270 * 271 * @return True upon successful deletion or 272 * False in case of an error 273 **/ 274 275void namecache_flush(void) 276{ 277 if (!gencache_init()) 278 return; 279 280 /* 281 * iterate through each NBT cache's entry and flush it 282 * by flush_netbios_name function 283 */ 284 gencache_iterate(flush_netbios_name, NULL, "NBT/*"); 285 DEBUG(5, ("Namecache flushed\n")); 286} 287 288/* Construct a name status record key. */ 289 290static char *namecache_status_record_key(const char *name, int name_type1, 291 int name_type2, struct in_addr keyip) 292{ 293 char *keystr; 294 295 asprintf(&keystr, "NBT/%s#%02X.%02X.%s", 296 strupper_static(name), name_type1, name_type2, inet_ntoa(keyip)); 297 return keystr; 298} 299 300/* Store a name status record. */ 301 302BOOL namecache_status_store(const char *keyname, int keyname_type, 303 int name_type, struct in_addr keyip, 304 const char *srvname) 305{ 306 char *key; 307 time_t expiry; 308 BOOL ret; 309 310 if (!gencache_init()) 311 return False; 312 313 key = namecache_status_record_key(keyname, keyname_type, name_type, keyip); 314 if (!key) 315 return False; 316 317 expiry = time(NULL) + lp_name_cache_timeout(); 318 ret = gencache_set(key, srvname, expiry); 319 320 if (ret) 321 DEBUG(5, ("namecache_status_store: entry %s -> %s\n", key, srvname )); 322 else 323 DEBUG(5, ("namecache_status_store: entry %s store failed.\n", key )); 324 325 SAFE_FREE(key); 326 return ret; 327} 328 329/* Fetch a name status record. */ 330 331BOOL namecache_status_fetch(const char *keyname, int keyname_type, 332 int name_type, struct in_addr keyip, char *srvname_out) 333{ 334 char *key = NULL; 335 char *value = NULL; 336 time_t timeout; 337 338 if (!gencache_init()) 339 return False; 340 341 key = namecache_status_record_key(keyname, keyname_type, name_type, keyip); 342 if (!key) 343 return False; 344 345 if (!gencache_get(key, &value, &timeout)) { 346 DEBUG(5, ("namecache_status_fetch: no entry for %s found.\n", key)); 347 SAFE_FREE(key); 348 return False; 349 } else { 350 DEBUG(5, ("namecache_status_fetch: key %s -> %s\n", key, value )); 351 } 352 353 strlcpy(srvname_out, value, 16); 354 SAFE_FREE(key); 355 SAFE_FREE(value); 356 return True; 357} 358