source4/lib/dbwrap/dbwrap_tdb.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    Database interface wrapper around tdb
   5
   6    Copyright (C) Volker Lendecke 2005
   7    Copyright (C) Andrew Tridgell 2007
   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 3 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, see <http://www.gnu.org/licenses/>.
  21 */
  22
  23 #include "includes.h"
  24 #include "lib/tdb/include/tdb.h"
  25 #include "lib/dbwrap/dbwrap.h"
  26 #include "system/filesys.h"
  27 #include "tdb_wrap.h"
  28 #include "param/param.h"
  29
  30 struct db_tdb_ctx {
  31         struct tdb_wrap *wtdb;
  32 };
  33
  34 static NTSTATUS db_tdb_store(struct db_record *rec, TDB_DATA data, int flag);
  35 static NTSTATUS db_tdb_delete(struct db_record *rec);
  36
  37 static int db_tdb_record_destr(struct db_record* data)
  38 {
  39         struct db_tdb_ctx *ctx = talloc_get_type(data->private_data, struct db_tdb_ctx);
  40
  41         if (tdb_chainunlock(ctx->wtdb->tdb, data->key) != 0) {
  42                 DEBUG(0, ("tdb_chainunlock failed\n"));
  43                 return -1;
  44         }
  45         return 0;
  46 }
  47
  48 static int db_tdb_fetch(struct db_context *db, TALLOC_CTX *mem_ctx, TDB_DATA key, TDB_DATA *data)
  49 {
  50         struct db_tdb_ctx *ctx = talloc_get_type(db->private_data, struct db_tdb_ctx);
  51         TDB_DATA value;
  52
  53         value = tdb_fetch(ctx->wtdb->tdb, key);
  54         if (value.dptr == NULL) {
  55                 return -1;
  56         }
  57
  58         data->dsize = value.dsize;
  59         data->dptr  = (uint8_t *)talloc_memdup(mem_ctx, value.dptr, value.dsize);
  60         free(value.dptr);
  61         if (data->dptr == NULL) {
  62                 errno = ENOMEM;
  63                 return -1;
  64         }
  65
  66         return 0;
  67 }
  68
  69 static struct db_record *db_tdb_fetch_locked(struct db_context *db,
  70                                      TALLOC_CTX *mem_ctx, TDB_DATA key)
  71 {
  72         struct db_tdb_ctx *ctx = talloc_get_type(db->private_data, struct db_tdb_ctx);
  73         struct db_record *result;
  74         TDB_DATA value;
  75
  76         result = talloc(mem_ctx, struct db_record);
  77         if (result == NULL) {
  78                 return NULL;
  79         }
  80
  81         result->key.dsize = key.dsize;
  82         result->key.dptr = (uint8_t *)talloc_memdup(result, key.dptr, key.dsize);
  83         if (result->key.dptr == NULL) {
  84                 talloc_free(result);
  85                 return NULL;
  86         }
  87
  88         result->value.dptr = NULL;
  89         result->value.dsize = 0;
  90         result->private_data = talloc_reference(result, ctx);
  91         result->store = db_tdb_store;
  92         result->delete_rec = db_tdb_delete;
  93
  94         if (tdb_chainlock(ctx->wtdb->tdb, key) != 0) {
  95                 talloc_free(result);
  96                 return NULL;
  97         }
  98
  99         talloc_set_destructor(result, db_tdb_record_destr);
 100
 101         value = tdb_fetch(ctx->wtdb->tdb, key);
 102
 103         if (value.dptr == NULL) {
 104                 return result;
 105         }
 106
 107         result->value.dsize = value.dsize;
 108         result->value.dptr = (uint8_t *)talloc_memdup(result, value.dptr,
 109                                                     value.dsize);
 110         free(value.dptr);
 111         if (result->value.dptr == NULL) {
 112                 talloc_free(result);
 113                 return NULL;
 114         }
 115
 116         return result;
 117 }
 118
 119 static NTSTATUS db_tdb_store(struct db_record *rec, TDB_DATA data, int flag)
 120 {
 121         struct db_tdb_ctx *ctx = talloc_get_type(rec->private_data, struct db_tdb_ctx);
 122
 123         /*
 124          * This has a bug: We need to replace rec->value for correct
 125          * operation, but right now brlock and locking don't use the value
 126          * anymore after it was stored.
 127          */
 128
 129         return (tdb_store(ctx->wtdb->tdb, rec->key, data, flag) == 0) ?
 130                 NT_STATUS_OK : NT_STATUS_UNSUCCESSFUL;
 131 }
 132
 133 static NTSTATUS db_tdb_delete(struct db_record *rec)
 134 {
 135         struct db_tdb_ctx *ctx = talloc_get_type(rec->private_data, struct db_tdb_ctx);
 136
 137         return (tdb_delete(ctx->wtdb->tdb, rec->key) == 0) ?
 138                 NT_STATUS_OK : NT_STATUS_UNSUCCESSFUL;
 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(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(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(db->private_data, struct db_tdb_ctx);
 222         return tdb_get_seqnum(db_ctx->wtdb->tdb);
 223 }
 224
 225 /*
 226   open a temporary database
 227  */
 228 struct db_context *db_tmp_open_tdb(TALLOC_CTX *mem_ctx, struct loadparm_context *lp_ctx,
 229                                    const char *name, int tdb_flags)
 230 {
 231         struct db_context *result;
 232         struct db_tdb_ctx *db_tdb;
 233         char *path;
 234
 235         result = talloc_zero(mem_ctx, struct db_context);
 236         if (result == NULL) goto failed;
 237
 238         db_tdb = talloc(result, struct db_tdb_ctx);
 239         if (db_tdb == NULL) goto failed;
 240
 241         result->private_data = db_tdb;
 242
 243         /* the name passed in should not be a full path, it should be
 244            just be the db name */
 245         path = smbd_tmp_path(result, lp_ctx, name);
 246
 247         db_tdb->wtdb = tdb_wrap_open(db_tdb, path, 0, tdb_flags,
 248                                      O_CREAT|O_RDWR, 0666);
 249         if (db_tdb->wtdb == NULL) {
 250                 DEBUG(3, ("Could not open tdb '%s': %s\n", path, strerror(errno)));
 251                 goto failed;
 252         }
 253
 254         talloc_free(path);
 255
 256         result->fetch_locked  = db_tdb_fetch_locked;
 257         result->fetch         = db_tdb_fetch;
 258         result->traverse      = db_tdb_traverse;
 259         result->traverse_read = db_tdb_traverse_read;
 260         result->get_seqnum    = db_tdb_get_seqnum;
 261
 262         return result;
 263
 264  failed:
 265         talloc_free(result);
 266         return NULL;
 267 }