lib/hdb/db3.c

   1 /*
   2  * Copyright (c) 1997 - 2006 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * 3. Neither the name of the Institute nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #include "hdb_locl.h"
  35
  36 #include <fcntl.h>
  37
  38 #if HAVE_DB3
  39
  40 #ifdef HAVE_DBHEADER
  41 #include <db.h>
  42 #elif HAVE_DB6_DB_H
  43 #include <db6/db.h>
  44 #elif HAVE_DB5_DB_H
  45 #include <db5/db.h>
  46 #elif HAVE_DB4_DB_H
  47 #include <db4/db.h>
  48 #elif HAVE_DB3_DB_H
  49 #include <db3/db.h>
  50 #else
  51 #include <db.h>
  52 #endif
  53
  54 typedef struct {
  55     HDB hdb;            /* generic members */
  56     int lock_fd;        /* DB3-specific */
  57 } DB3_HDB;
  58
  59
  60 static krb5_error_code
  61 DB_close(krb5_context context, HDB *db)
  62 {
  63     DB3_HDB *db3 = (DB3_HDB *)db;
  64     DB *d = (DB*)db->hdb_db;
  65     DBC *dbcp = (DBC*)db->hdb_dbc;
  66
  67     heim_assert(d != 0, "Closing already closed HDB");
  68
  69     if (dbcp != NULL)
  70         dbcp->c_close(dbcp);
  71     if (d != NULL)
  72         d->close(d, 0);
  73     if (db3->lock_fd >= 0)
  74         close(db3->lock_fd);
  75
  76     db3->lock_fd = -1;
  77     db->hdb_dbc = 0;
  78     db->hdb_db = 0;
  79
  80     return 0;
  81 }
  82
  83 static krb5_error_code
  84 DB_destroy(krb5_context context, HDB *db)
  85 {
  86     krb5_error_code ret;
  87
  88     ret = hdb_clear_master_key (context, db);
  89     free(db->hdb_name);
  90     free(db);
  91     return ret;
  92 }
  93
  94 static krb5_error_code
  95 DB_lock(krb5_context context, HDB *db, int operation)
  96 {
  97
  98     return 0;
  99 }
 100
 101 static krb5_error_code
 102 DB_unlock(krb5_context context, HDB *db)
 103 {
 104
 105     return 0;
 106 }
 107
 108
 109 static krb5_error_code
 110 DB_seq(krb5_context context, HDB *db,
 111        unsigned flags, hdb_entry_ex *entry, int flag)
 112 {
 113     DBT key, value;
 114     DBC *dbcp = db->hdb_dbc;
 115     krb5_data key_data, data;
 116     int code;
 117
 118     memset(&key, 0, sizeof(DBT));
 119     memset(&value, 0, sizeof(DBT));
 120     code = (*dbcp->c_get)(dbcp, &key, &value, flag);
 121     if (code == DB_NOTFOUND)
 122         return HDB_ERR_NOENTRY;
 123     if (code)
 124         return code;
 125
 126     key_data.data = key.data;
 127     key_data.length = key.size;
 128     data.data = value.data;
 129     data.length = value.size;
 130     memset(entry, 0, sizeof(*entry));
 131     if (hdb_value2entry(context, &data, &entry->entry))
 132         return DB_seq(context, db, flags, entry, DB_NEXT);
 133     if (db->hdb_master_key_set && (flags & HDB_F_DECRYPT)) {
 134         code = hdb_unseal_keys (context, db, &entry->entry);
 135         if (code)
 136             hdb_free_entry (context, entry);
 137     }
 138     if (entry->entry.principal == NULL) {
 139         entry->entry.principal = malloc(sizeof(*entry->entry.principal));
 140         if (entry->entry.principal == NULL) {
 141             hdb_free_entry (context, entry);
 142             krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
 143             return ENOMEM;
 144         } else {
 145             hdb_key2principal(context, &key_data, entry->entry.principal);
 146         }
 147     }
 148     return 0;
 149 }
 150
 151
 152 static krb5_error_code
 153 DB_firstkey(krb5_context context, HDB *db, unsigned flags, hdb_entry_ex *entry)
 154 {
 155     return DB_seq(context, db, flags, entry, DB_FIRST);
 156 }
 157
 158
 159 static krb5_error_code
 160 DB_nextkey(krb5_context context, HDB *db, unsigned flags, hdb_entry_ex *entry)
 161 {
 162     return DB_seq(context, db, flags, entry, DB_NEXT);
 163 }
 164
 165 static krb5_error_code
 166 DB_rename(krb5_context context, HDB *db, const char *new_name)
 167 {
 168     int ret;
 169     char *old, *new;
 170
 171     ret = asprintf(&old, "%s.db", db->hdb_name);
 172     if (ret == -1)
 173         return ENOMEM;
 174     ret = asprintf(&new, "%s.db", new_name);
 175     if (ret == -1) {
 176         free(old);
 177         return ENOMEM;
 178     }
 179     ret = rename(old, new);
 180     free(old);
 181     if(ret) {
 182         free(new);
 183         return errno;
 184     }
 185
 186     free(db->hdb_name);
 187     new[strlen(new) - 3] = '\0';
 188     db->hdb_name = new;
 189     return 0;
 190 }
 191
 192 static krb5_error_code
 193 DB__get(krb5_context context, HDB *db, krb5_data key, krb5_data *reply)
 194 {
 195     DB *d = (DB*)db->hdb_db;
 196     DBT k, v;
 197     int code;
 198
 199     memset(&k, 0, sizeof(DBT));
 200     memset(&v, 0, sizeof(DBT));
 201     k.data = key.data;
 202     k.size = key.length;
 203     k.flags = 0;
 204     code = (*d->get)(d, NULL, &k, &v, 0);
 205     if(code == DB_NOTFOUND)
 206         return HDB_ERR_NOENTRY;
 207     if(code)
 208         return code;
 209
 210     krb5_data_copy(reply, v.data, v.size);
 211     return 0;
 212 }
 213
 214 static krb5_error_code
 215 DB__put(krb5_context context, HDB *db, int replace,
 216         krb5_data key, krb5_data value)
 217 {
 218     DB *d = (DB*)db->hdb_db;
 219     DBT k, v;
 220     int code;
 221
 222     memset(&k, 0, sizeof(DBT));
 223     memset(&v, 0, sizeof(DBT));
 224     k.data = key.data;
 225     k.size = key.length;
 226     k.flags = 0;
 227     v.data = value.data;
 228     v.size = value.length;
 229     v.flags = 0;
 230     code = (*d->put)(d, NULL, &k, &v, replace ? 0 : DB_NOOVERWRITE);
 231     if(code == DB_KEYEXIST)
 232         return HDB_ERR_EXISTS;
 233     if(code)
 234         return errno;
 235     return 0;
 236 }
 237
 238 static krb5_error_code
 239 DB__del(krb5_context context, HDB *db, krb5_data key)
 240 {
 241     DB *d = (DB*)db->hdb_db;
 242     DBT k;
 243     krb5_error_code code;
 244     memset(&k, 0, sizeof(DBT));
 245     k.data = key.data;
 246     k.size = key.length;
 247     k.flags = 0;
 248     code = (*d->del)(d, NULL, &k, 0);
 249     if(code == DB_NOTFOUND)
 250         return HDB_ERR_NOENTRY;
 251     if(code)
 252         return code;
 253     return 0;
 254 }
 255
 256 #define RD_CACHE_SZ 0x8000     /* Minimal read cache size */
 257 #define WR_CACHE_SZ 0x8000     /* Minimal write cache size */
 258
 259 static int
 260 _open_db(DB *d, char *fn, int myflags, int flags, mode_t mode, int *fd)
 261 {
 262     int ret;
 263     int cache_size = (myflags & DB_RDONLY) ? RD_CACHE_SZ : WR_CACHE_SZ;
 264
 265     *fd = open(fn, flags, mode);
 266
 267     if (*fd == -1)
 268        return errno;
 269
 270     /*
 271      * Without DB_FCNTL_LOCKING, the DB library complains when initializing
 272      * a database in an empty file. Since the database is our lock file,
 273      * we create it before Berkeley DB does, so a new DB always starts empty.
 274      */
 275     myflags |= DB_FCNTL_LOCKING;
 276
 277     ret = flock(*fd, (myflags&DB_RDONLY) ? LOCK_SH : LOCK_EX);
 278     if (ret == -1) {
 279         ret = errno;
 280         close(*fd);
 281         *fd = -1;
 282         return ret;
 283     }
 284
 285     d->set_cachesize(d, 0, cache_size, 0);
 286
 287 #if (DB_VERSION_MAJOR > 4) || ((DB_VERSION_MAJOR == 4) && (DB_VERSION_MINOR >= 1))
 288     ret = (*d->open)(d, NULL, fn, NULL, DB_BTREE, myflags, mode);
 289 #else
 290     ret = (*d->open)(d, fn, NULL, DB_BTREE, myflags, mode);
 291 #endif
 292
 293     if (ret != 0) {
 294         close(*fd);
 295         *fd = -1;
 296     }
 297
 298     return ret;
 299 }
 300
 301 static krb5_error_code
 302 DB_open(krb5_context context, HDB *db, int flags, mode_t mode)
 303 {
 304     DB3_HDB *db3 = (DB3_HDB *)db;
 305     DBC *dbc = NULL;
 306     char *fn;
 307     krb5_error_code ret;
 308     DB *d;
 309     int myflags = 0;
 310     int aret;
 311
 312     heim_assert(db->hdb_db == 0, "Opening already open HDB");
 313
 314     if (flags & O_CREAT)
 315       myflags |= DB_CREATE;
 316
 317     if (flags & O_EXCL)
 318       myflags |= DB_EXCL;
 319
 320     if((flags & O_ACCMODE) == O_RDONLY)
 321       myflags |= DB_RDONLY;
 322
 323     if (flags & O_TRUNC)
 324       myflags |= DB_TRUNCATE;
 325
 326     aret = asprintf(&fn, "%s.db", db->hdb_name);
 327     if (aret == -1) {
 328         krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
 329         return ENOMEM;
 330     }
 331
 332     if (db_create(&d, NULL, 0) != 0) {
 333         free(fn);
 334         krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
 335         return ENOMEM;
 336     }
 337     db->hdb_db = d;
 338
 339     /* From here on out always DB_close() before returning on error */
 340
 341     ret = _open_db(d, fn, myflags, flags, mode, &db3->lock_fd);
 342     free(fn);
 343     if (ret == ENOENT) {
 344         /* try to open without .db extension */
 345         ret = _open_db(d, db->hdb_name, myflags, flags, mode, &db3->lock_fd);
 346     }
 347
 348     if (ret) {
 349         DB_close(context, db);
 350         krb5_set_error_message(context, ret, "opening %s: %s",
 351                                db->hdb_name, strerror(ret));
 352         return ret;
 353     }
 354
 355 #ifndef DB_CURSOR_BULK
 356 # define DB_CURSOR_BULK 0       /* Missing with DB < 4.8 */
 357 #endif
 358     ret = (*d->cursor)(d, NULL, &dbc, DB_CURSOR_BULK);
 359
 360     if (ret) {
 361         DB_close(context, db);
 362         krb5_set_error_message(context, ret, "d->cursor: %s", strerror(ret));
 363         return ret;
 364     }
 365     db->hdb_dbc = dbc;
 366
 367     if((flags & O_ACCMODE) == O_RDONLY)
 368         ret = hdb_check_db_format(context, db);
 369     else
 370         ret = hdb_init_db(context, db);
 371     if(ret == HDB_ERR_NOENTRY)
 372         return 0;
 373     if (ret) {
 374         DB_close(context, db);
 375         krb5_set_error_message(context, ret, "hdb_open: failed %s database %s",
 376                                (flags & O_ACCMODE) == O_RDONLY ?
 377                                "checking format of" : "initialize",
 378                                db->hdb_name);
 379     }
 380
 381     return ret;
 382 }
 383
 384 krb5_error_code
 385 hdb_db_create(krb5_context context, HDB **db,
 386               const char *filename)
 387 {
 388     DB3_HDB **db3 = (DB3_HDB **)db;
 389     *db = calloc(1, sizeof(**db3));    /* Allocate space for the larger db3 */
 390     if (*db == NULL) {
 391         krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
 392         return ENOMEM;
 393     }
 394
 395     (*db)->hdb_db = NULL;
 396     (*db)->hdb_name = strdup(filename);
 397     if ((*db)->hdb_name == NULL) {
 398         free(*db);
 399         *db = NULL;
 400         krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
 401         return ENOMEM;
 402     }
 403     (*db)->hdb_master_key_set = 0;
 404     (*db)->hdb_openp = 0;
 405     (*db)->hdb_capability_flags = HDB_CAP_F_HANDLE_ENTERPRISE_PRINCIPAL;
 406     (*db)->hdb_open  = DB_open;
 407     (*db)->hdb_close = DB_close;
 408     (*db)->hdb_fetch_kvno = _hdb_fetch_kvno;
 409     (*db)->hdb_store = _hdb_store;
 410     (*db)->hdb_remove = _hdb_remove;
 411     (*db)->hdb_firstkey = DB_firstkey;
 412     (*db)->hdb_nextkey= DB_nextkey;
 413     (*db)->hdb_lock = DB_lock;
 414     (*db)->hdb_unlock = DB_unlock;
 415     (*db)->hdb_rename = DB_rename;
 416     (*db)->hdb__get = DB__get;
 417     (*db)->hdb__put = DB__put;
 418     (*db)->hdb__del = DB__del;
 419     (*db)->hdb_destroy = DB_destroy;
 420
 421     (*db3)->lock_fd = -1;
 422     return 0;
 423 }
 424 #endif /* HAVE_DB3 */