source/lib/dbwrap_tdb.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Database interface wrapper around tdb
   4    Copyright (C) Volker Lendecke 2005-2007
   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 2 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, write to the Free Software
  18    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19 */
  20
  21 #include "includes.h"
  22
  23 struct db_tdb_ctx {
  24         struct tdb_wrap *wtdb;
  25 };
  26
  27 static NTSTATUS db_tdb_store(struct db_record *rec, TDB_DATA data, int flag);
  28 static NTSTATUS db_tdb_delete(struct db_record *rec);
  29
  30 static int db_tdb_record_destr(struct db_record* data)
  31 {
  32         struct db_tdb_ctx *ctx =
  33                 talloc_get_type_abort(data->private_data, struct db_tdb_ctx);
  34
  35         DEBUG(10, ("Unlocking key %s\n",
  36                    hex_encode(data, (unsigned char *)data->key.dptr,
  37                               data->key.dsize)));
  38
  39         if (tdb_chainunlock(ctx->wtdb->tdb, data->key) != 0) {
  40                 DEBUG(0, ("tdb_chainunlock failed\n"));
  41                 return -1;
  42         }
  43         return 0;
  44 }
  45
  46 static struct db_record *db_tdb_fetch_locked(struct db_context *db,
  47                                      TALLOC_CTX *mem_ctx, TDB_DATA key)
  48 {
  49         struct db_tdb_ctx *ctx = talloc_get_type_abort(db->private_data,
  50                                                        struct db_tdb_ctx);
  51         struct db_record *result;
  52         TDB_DATA value;
  53
  54         result = TALLOC_P(mem_ctx, struct db_record);
  55         if (result == NULL) {
  56                 DEBUG(0, ("talloc failed\n"));
  57                 return NULL;
  58         }
  59
  60         result->key.dsize = key.dsize;
  61         result->key.dptr = (uint8 *)talloc_memdup(result, key.dptr, key.dsize);
  62         if (result->key.dptr == NULL) {
  63                 DEBUG(0, ("talloc failed\n"));
  64                 TALLOC_FREE(result);
  65                 return NULL;
  66         }
  67
  68         result->value.dptr = NULL;
  69         result->value.dsize = 0;
  70         result->private_data = talloc_reference(result, ctx);
  71         result->store = db_tdb_store;
  72         result->delete_rec = db_tdb_delete;
  73
  74         {
  75                 char *keystr = hex_encode(NULL, (unsigned char *)key.dptr,
  76                                           key.dsize);
  77                 DEBUG(10, ("Locking key %s\n", keystr));
  78                 TALLOC_FREE(keystr);
  79         }
  80
  81         if (tdb_chainlock(ctx->wtdb->tdb, key) != 0) {
  82                 DEBUG(3, ("tdb_chainlock failed\n"));
  83                 TALLOC_FREE(result);
  84                 return NULL;
  85         }
  86
  87         talloc_set_destructor(result, db_tdb_record_destr);
  88
  89         value = tdb_fetch(ctx->wtdb->tdb, key);
  90
  91         if (value.dptr == NULL) {
  92                 return result;
  93         }
  94
  95         result->value.dsize = value.dsize;
  96         result->value.dptr = (uint8 *)talloc_memdup(result, value.dptr,
  97                                                     value.dsize);
  98         if (result->value.dptr == NULL) {
  99                 DEBUG(3, ("talloc failed\n"));
 100                 TALLOC_FREE(result);
 101                 return NULL;
 102         }
 103
 104         SAFE_FREE(value.dptr);
 105
 106         DEBUG(10, ("Allocated locked data 0x%p\n", result));
 107
 108         return result;
 109 }
 110
 111 static NTSTATUS db_tdb_store(struct db_record *rec, TDB_DATA data, int flag)
 112 {
 113         struct db_tdb_ctx *ctx = talloc_get_type_abort(rec->private_data,
 114                                                        struct db_tdb_ctx);
 115
 116         /*
 117          * This has a bug: We need to replace rec->value for correct
 118          * operation, but right now brlock and locking don't use the value
 119          * anymore after it was stored.
 120          */
 121
 122         return (tdb_store(ctx->wtdb->tdb, rec->key, data, flag) == 0) ?
 123                 NT_STATUS_OK : NT_STATUS_UNSUCCESSFUL;
 124 }
 125
 126 static NTSTATUS db_tdb_delete(struct db_record *rec)
 127 {
 128         struct db_tdb_ctx *ctx = talloc_get_type_abort(rec->private_data,
 129                                                        struct db_tdb_ctx);
 130         int res;
 131
 132         res = tdb_delete(ctx->wtdb->tdb, rec->key);
 133
 134         if (res == 0) {
 135                 return NT_STATUS_OK;
 136         }
 137
 138         return map_nt_error_from_tdb(tdb_error(ctx->wtdb->tdb));
 139 }
 140
 141 struct db_tdb_traverse_ctx {
 142         struct db_context *db;
 143         int (*f)(struct db_record *rec, void *private_data);
 144         void *private_data;
 145 };
 146
 147 static int db_tdb_traverse_func(TDB_CONTEXT *tdb, TDB_DATA kbuf, TDB_DATA dbuf,
 148                                 void *private_data)
 149 {
 150         struct db_tdb_traverse_ctx *ctx =
 151                 (struct db_tdb_traverse_ctx *)private_data;
 152         struct db_record rec;
 153
 154         rec.key = kbuf;
 155         rec.value = dbuf;
 156         rec.store = db_tdb_store;
 157         rec.delete_rec = db_tdb_delete;
 158         rec.private_data = ctx->db->private_data;
 159
 160         return ctx->f(&rec, ctx->private_data);
 161 }
 162
 163 static int db_tdb_traverse(struct db_context *db,
 164                            int (*f)(struct db_record *rec, void *private_data),
 165                            void *private_data)
 166 {
 167         struct db_tdb_ctx *db_ctx =
 168                 talloc_get_type_abort(db->private_data, struct db_tdb_ctx);
 169         struct db_tdb_traverse_ctx ctx;
 170
 171         ctx.db = db;
 172         ctx.f = f;
 173         ctx.private_data = private_data;
 174         return tdb_traverse(db_ctx->wtdb->tdb, db_tdb_traverse_func, &ctx);
 175 }
 176
 177 static NTSTATUS db_tdb_store_deny(struct db_record *rec, TDB_DATA data, int flag)
 178 {
 179         return NT_STATUS_MEDIA_WRITE_PROTECTED;
 180 }
 181
 182 static NTSTATUS db_tdb_delete_deny(struct db_record *rec)
 183 {
 184         return NT_STATUS_MEDIA_WRITE_PROTECTED;
 185 }
 186
 187 static int db_tdb_traverse_read_func(TDB_CONTEXT *tdb, TDB_DATA kbuf, TDB_DATA dbuf,
 188                                 void *private_data)
 189 {
 190         struct db_tdb_traverse_ctx *ctx =
 191                 (struct db_tdb_traverse_ctx *)private_data;
 192         struct db_record rec;
 193
 194         rec.key = kbuf;
 195         rec.value = dbuf;
 196         rec.store = db_tdb_store_deny;
 197         rec.delete_rec = db_tdb_delete_deny;
 198         rec.private_data = ctx->db->private_data;
 199
 200         return ctx->f(&rec, ctx->private_data);
 201 }
 202
 203 static int db_tdb_traverse_read(struct db_context *db,
 204                            int (*f)(struct db_record *rec, void *private_data),
 205                            void *private_data)
 206 {
 207         struct db_tdb_ctx *db_ctx =
 208                 talloc_get_type_abort(db->private_data, struct db_tdb_ctx);
 209         struct db_tdb_traverse_ctx ctx;
 210
 211         ctx.db = db;
 212         ctx.f = f;
 213         ctx.private_data = private_data;
 214         return tdb_traverse_read(db_ctx->wtdb->tdb, db_tdb_traverse_read_func, &ctx);
 215 }
 216
 217 static int db_tdb_get_seqnum(struct db_context *db)
 218
 219 {
 220         struct db_tdb_ctx *db_ctx =
 221                 talloc_get_type_abort(db->private_data, struct db_tdb_ctx);
 222         return tdb_get_seqnum(db_ctx->wtdb->tdb);
 223 }
 224
 225 struct db_context *db_open_tdb(TALLOC_CTX *mem_ctx,
 226                                const char *name,
 227                                int hash_size, int tdb_flags,
 228                                int open_flags, mode_t mode)
 229 {
 230         struct db_context *result = NULL;
 231         struct db_tdb_ctx *db_tdb;
 232
 233         result = TALLOC_ZERO_P(mem_ctx, struct db_context);
 234         if (result == NULL) {
 235                 DEBUG(0, ("talloc failed\n"));
 236                 goto fail;
 237         }
 238
 239         result->private_data = db_tdb = TALLOC_P(result, struct db_tdb_ctx);
 240         if (db_tdb == NULL) {
 241                 DEBUG(0, ("talloc failed\n"));
 242                 goto fail;
 243         }
 244
 245         db_tdb->wtdb = tdb_wrap_open(db_tdb, name, hash_size, tdb_flags,
 246                                      open_flags, mode);
 247         if (db_tdb->wtdb == NULL) {
 248                 DEBUG(3, ("Could not open tdb: %s\n", strerror(errno)));
 249                 goto fail;
 250         }
 251
 252         result->fetch_locked = db_tdb_fetch_locked;
 253         result->traverse = db_tdb_traverse;
 254         result->traverse_read = db_tdb_traverse_read;
 255         result->get_seqnum = db_tdb_get_seqnum;
 256         return result;
 257
 258  fail:
 259         if (result != NULL) {
 260                 TALLOC_FREE(result);
 261         }
 262         return NULL;
 263 }