/src/samba/source3/registry/reg_backend_db.c

Source
/* 
 *  Unix SMB/CIFS implementation.
 *  Virtual Windows Registry Layer
 *  Copyright (C) Gerald Carter                     2002-2005
 *  Copyright (C) Michael Adam                      2007-2011
 *  Copyright (C) Gregor Beck                       2011
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 3 of the License, or
 *  (at your option) any later version.
 *  
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *  
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, see <http://www.gnu.org/licenses/>.
 */

/* Implementation of internal registry database functions. */

#include "includes.h"
#include "system/filesys.h"
#include "registry.h"
#include "reg_db.h"
#include "reg_util_internal.h"
#include "reg_parse_internal.h"
#include "reg_backend_db.h"
#include "reg_objects.h"
#include "nt_printing.h"
#include "util_tdb.h"
#include "dbwrap/dbwrap.h"
#include "dbwrap/dbwrap_open.h"
#include "../libcli/security/secdesc.h"

#undef DBGC_CLASS
#define DBGC_CLASS DBGC_REGISTRY

#define REGDB_VERSION_KEYNAME "INFO/version"

static struct db_context *regdb = NULL;
static int regdb_refcount;

static bool regdb_key_exists(struct db_context *db, const char *key);
static WERROR regdb_fetch_keys_internal(struct db_context *db, const char *key,
          struct regsubkey_ctr *ctr);
static bool regdb_store_keys_internal(struct db_context *db, const char *key,
              struct regsubkey_ctr *ctr);
static int regdb_fetch_values_internal(struct db_context *db, const char* key,
               struct regval_ctr *values);
static NTSTATUS regdb_store_values_internal(struct db_context *db, const char *key,
              struct regval_ctr *values);
static WERROR regdb_store_subkey_list(struct db_context *db, const char *parent,
              const char *key);

static WERROR regdb_create_basekey(struct db_context *db, const char *key);
static WERROR regdb_create_subkey_internal(struct db_context *db,
             const char *key,
             const char *subkey);


struct regdb_trans_ctx {
  NTSTATUS (*action)(struct db_context *, void *);
  void *private_data;
};

static NTSTATUS regdb_trans_do_action(struct db_context *db, void *private_data)
{
  NTSTATUS status;
  int32_t version_id;
  struct regdb_trans_ctx *ctx = (struct regdb_trans_ctx *)private_data;

  status = dbwrap_fetch_int32_bystring(db, REGDB_VERSION_KEYNAME,
               &version_id);

  if (!NT_STATUS_IS_OK(status)) {
    DEBUG(0, ("ERROR: could not fetch registry db version: %s. "
        "Denying access.\n", nt_errstr(status)));
    return NT_STATUS_ACCESS_DENIED;
  }

  if (version_id != REGDB_CODE_VERSION) {
    DEBUG(0, ("ERROR: changed registry version %d found while "
        "trying to write to the registry. Version %d "
        "expected.  Denying access.\n",
        version_id, REGDB_CODE_VERSION));
    return NT_STATUS_ACCESS_DENIED;
  }

  status = ctx->action(db,  ctx->private_data);
  return status;
}

static WERROR regdb_trans_do(struct db_context *db,
           NTSTATUS (*action)(struct db_context *, void *),
           void *private_data)
{
  NTSTATUS status;
  struct regdb_trans_ctx ctx;


  ctx.action = action;
  ctx.private_data = private_data;

  status = dbwrap_trans_do(db, regdb_trans_do_action, &ctx);

  return ntstatus_to_werror(status);
}

/* List the deepest path into the registry.  All part components will be created.*/

/* If you want to have a part of the path controlled by the tdb and part by
   a virtual registry db (e.g. printing), then you have to list the deepest path.
   For example,"HKLM/SOFTWARE/Microsoft/Windows NT/CurrentVersion/Print" 
   allows the reg_db backend to handle everything up to 
   "HKLM/SOFTWARE/Microsoft/Windows NT/CurrentVersion" and then we'll hook 
   the reg_printing backend onto the last component of the path (see 
   KEY_PRINTING_2K in include/rpc_reg.h)   --jerry */

static const char *builtin_registry_paths[] = {
  KEY_PRINTING_2K,
  KEY_PCC,
  KEY_PRINTING_PORTS,
  KEY_PRINTING,
  KEY_PRINTING "\\Forms",
  KEY_PRINTING "\\Printers",
  KEY_PRINTING "\\Environments\\Windows NT x86\\Print Processors\\winprint",
  KEY_PRINTING "\\Environments\\Windows x64\\Print Processors\\winprint",
  KEY_SHARES,
  KEY_EVENTLOG,
  KEY_SMBCONF,
  KEY_PERFLIB,
  KEY_PERFLIB_009,
  KEY_GROUP_POLICY,
  KEY_SAMBA_GROUP_POLICY,
  KEY_GP_MACHINE_POLICY,
  KEY_GP_MACHINE_WIN_POLICY,
  KEY_HKCU,
  KEY_GP_USER_POLICY,
  KEY_GP_USER_WIN_POLICY,
  "HKLM\\Software\\Microsoft\\Windows NT\\CurrentVersion\\Winlogon\\GPExtensions",
  "HKLM\\SYSTEM\\CurrentControlSet\\Control\\Print\\Monitors",
  KEY_PROD_OPTIONS,
  "HKLM\\SYSTEM\\CurrentControlSet\\Control\\Terminal Server\\DefaultUserConfiguration",
  KEY_TCPIP_PARAMS,
  KEY_NETLOGON_PARAMS,
  KEY_HKU,
  KEY_HKCR,
  KEY_HKPD,
  KEY_HKPT,
   NULL };

struct builtin_regkey_value {
  const char *path;
  const char *valuename;
  uint32_t type;
  union {
    const char *string;
    uint32_t dw_value;
  } data;
};

static struct builtin_regkey_value builtin_registry_values[] = {
  { KEY_PRINTING_PORTS,
    SAMBA_PRINTER_PORT_NAME, REG_SZ, { "" } },
  { KEY_PRINTING_2K,
    "DefaultSpoolDirectory", REG_SZ, { "C:\\Windows\\System32\\Spool\\Printers" } },
  { KEY_EVENTLOG,
    "DisplayName", REG_SZ, { "Event Log" } },
  { KEY_EVENTLOG,
    "ErrorControl", REG_DWORD, { (char*)0x00000001 } },
  { NULL, NULL, 0, { NULL } }
};

static WERROR create_key_recursive(struct db_context *db,
           char *path,
           const char *subkey)
{
  WERROR werr;
  char *p;

  if (subkey == NULL) {
    return WERR_INVALID_PARAMETER;
  }

  if (path == NULL) {
    return regdb_create_basekey(db, subkey);
  }

  p = strrchr_m(path, '\\');

  if (p == NULL) {
    werr = create_key_recursive(db, NULL, path);
  } else {
    *p = '\0';
    werr = create_key_recursive(db, path, p+1);
    *p = '\\';
  }

  if (!W_ERROR_IS_OK(werr)) {
    goto done;
  }

  werr = regdb_create_subkey_internal(db, path, subkey);

done:
  return werr;
}

/**
 * Initialize a key in the registry:
 * create each component key of the specified path.
 */
static WERROR init_registry_key_internal(struct db_context *db,
           const char *add_path)
{
  char *subkey, *key;
  WERROR werr;
  TALLOC_CTX *frame = talloc_stackframe();

  if (add_path == NULL) {
    werr = WERR_INVALID_PARAMETER;
    goto done;
  }

  key = talloc_strdup(frame, add_path);

  subkey = strrchr_m(key, '\\');
  if (subkey == NULL) {
    subkey = key;
    key = NULL;
  } else {
    *subkey = '\0';
    subkey++;
  }

  werr = create_key_recursive(db, key, subkey);

done:
  talloc_free(frame);
  return werr;
}

struct init_registry_key_context {
  const char *add_path;
};

static NTSTATUS init_registry_key_action(struct db_context *db,
           void *private_data)
{
  struct init_registry_key_context *init_ctx =
    (struct init_registry_key_context *)private_data;

  return werror_to_ntstatus(init_registry_key_internal(
          db, init_ctx->add_path));
}

/**
 * Initialize a key in the registry:
 * create each component key of the specified path,
 * wrapped in one db transaction.
 */
WERROR init_registry_key(const char *add_path)
{
  struct init_registry_key_context init_ctx;

  if (regdb_key_exists(regdb, add_path)) {
    return WERR_OK;
  }

  init_ctx.add_path = add_path;

  return regdb_trans_do(regdb,
            init_registry_key_action,
            &init_ctx);
}

/***********************************************************************
 Open the registry data in the tdb
 ***********************************************************************/

static void regdb_ctr_add_value(struct regval_ctr *ctr,
        struct builtin_regkey_value *value)
{
  switch(value->type) {
  case REG_DWORD:
    regval_ctr_addvalue(ctr, value->valuename, REG_DWORD,
            (uint8_t *)&value->data.dw_value,
            sizeof(uint32_t));
    break;

  case REG_SZ:
    regval_ctr_addvalue_sz(ctr, value->valuename,
               value->data.string);
    break;

  default:
    DEBUG(0, ("regdb_ctr_add_value: invalid value type in "
        "registry values [%d]\n", value->type));
  }
}

static NTSTATUS init_registry_data_action(struct db_context *db,
            void *private_data)
{
  NTSTATUS status;
  TALLOC_CTX *frame = talloc_stackframe();
  struct regval_ctr *values;
  int i;

  /* loop over all of the predefined paths and add each component */

  for (i=0; builtin_registry_paths[i] != NULL; i++) {
    if (regdb_key_exists(db, builtin_registry_paths[i])) {
      continue;
    }
    status = werror_to_ntstatus(init_registry_key_internal(db,
              builtin_registry_paths[i]));
    if (!NT_STATUS_IS_OK(status)) {
      goto done;
    }
  }

  /* loop over all of the predefined values and add each component */

  for (i=0; builtin_registry_values[i].path != NULL; i++) {
    WERROR werr;

    werr = regval_ctr_init(frame, &values);
    if (!W_ERROR_IS_OK(werr)) {
      status = werror_to_ntstatus(werr);
      goto done;
    }

    regdb_fetch_values_internal(db,
              builtin_registry_values[i].path,
              values);

    /* preserve existing values across restarts. Only add new ones */

    if (!regval_ctr_value_exists(values,
          builtin_registry_values[i].valuename))
    {
      regdb_ctr_add_value(values,
              &builtin_registry_values[i]);
      status = regdb_store_values_internal(db,
          builtin_registry_values[i].path,
          values);
      if (!NT_STATUS_IS_OK(status)) {
        goto done;
      }
    }
    TALLOC_FREE(values);
  }

  status = NT_STATUS_OK;

done:

  TALLOC_FREE(frame);
  return status;
}

WERROR init_registry_data(void)
{
  WERROR werr;
  TALLOC_CTX *frame = talloc_stackframe();
  struct regval_ctr *values;
  int i;

  /*
   * First, check for the existence of the needed keys and values.
   * If all do already exist, we can save the writes.
   */
  for (i=0; builtin_registry_paths[i] != NULL; i++) {
    if (!regdb_key_exists(regdb, builtin_registry_paths[i])) {
      goto do_init;
    }
  }

  for (i=0; builtin_registry_values[i].path != NULL; i++) {
    werr = regval_ctr_init(frame, &values);
    W_ERROR_NOT_OK_GOTO_DONE(werr);

    regdb_fetch_values_internal(regdb,
              builtin_registry_values[i].path,
              values);
    if (!regval_ctr_value_exists(values,
          builtin_registry_values[i].valuename))
    {
      TALLOC_FREE(values);
      goto do_init;
    }

    TALLOC_FREE(values);
  }

  werr = WERR_OK;
  goto done;

do_init:

  /*
   * There are potentially quite a few store operations which are all
   * individually wrapped in tdb transactions. Wrapping them in a single
   * transaction gives just a single transaction_commit() to actually do
   * its fsync()s. See tdb/common/transaction.c for info about nested
   * transaction behaviour.
   */

  werr = regdb_trans_do(regdb,
            init_registry_data_action,
            NULL);

done:
  TALLOC_FREE(frame);
  return werr;
}

static int regdb_normalize_keynames_fn(struct db_record *rec,
               void *private_data)
{
  TALLOC_CTX *mem_ctx = talloc_tos();
  const char *keyname;
  NTSTATUS status;
  TDB_DATA key;
  TDB_DATA value;
  struct db_context *db = (struct db_context *)private_data;

  key = dbwrap_record_get_key(rec);
  if (key.dptr == NULL || key.dsize == 0) {
    return 0;
  }

  value = dbwrap_record_get_value(rec);

  if (db == NULL) {
    DEBUG(0, ("regdb_normalize_keynames_fn: ERROR: "
        "NULL db context handed in via private_data\n"));
    return 1;
  }

  if (strncmp((const char *)key.dptr, REGDB_VERSION_KEYNAME,
      strlen(REGDB_VERSION_KEYNAME)) == 0)
  {
    return 0;
  }

  keyname = strchr((const char *)key.dptr, '/');
  if (keyname) {
    keyname = talloc_string_sub(mem_ctx,
              (const char *)key.dptr,
              "/",
              "\\");

    DEBUG(2, ("regdb_normalize_keynames_fn: Convert %s to %s\n",
        (const char *)key.dptr,
        keyname));

    /* Delete the original record and store the normalized key */
    status = dbwrap_record_delete(rec);
    if (!NT_STATUS_IS_OK(status)) {
      DEBUG(0,("regdb_normalize_keynames_fn: "
         "tdb_delete for [%s] failed!\n",
         (const char *)key.dptr));
      return 1;
    }

    status = dbwrap_store_bystring(db, keyname, value, TDB_REPLACE);
    if (!NT_STATUS_IS_OK(status)) {
      DEBUG(0,("regdb_normalize_keynames_fn: "
         "failed to store new record for [%s]!\n",
         keyname));
      return 1;
    }
  }

  return 0;
}

static WERROR regdb_store_regdb_version(struct db_context *db, uint32_t version)
{
  NTSTATUS status;
  if (db == NULL) {
    return WERR_CAN_NOT_COMPLETE;
  }

  status = dbwrap_trans_store_int32_bystring(db, REGDB_VERSION_KEYNAME,
               version);
  if (!NT_STATUS_IS_OK(status)) {
    DEBUG(1, ("regdb_store_regdb_version: error storing %s = %d: %s\n",
        REGDB_VERSION_KEYNAME, version, nt_errstr(status)));
    return ntstatus_to_werror(status);
  } else {
    DEBUG(10, ("regdb_store_regdb_version: stored %s = %d\n",
        REGDB_VERSION_KEYNAME, version));
    return WERR_OK;
  }
}

static WERROR regdb_upgrade_v1_to_v2(struct db_context *db)
{
  TALLOC_CTX *mem_ctx;
  NTSTATUS status;
  WERROR werr;

  mem_ctx = talloc_stackframe();

  status = dbwrap_traverse(db, regdb_normalize_keynames_fn, db, NULL);
  if (!NT_STATUS_IS_OK(status)) {
    werr = WERR_REGISTRY_IO_FAILED;
    goto done;
  }

  werr = regdb_store_regdb_version(db, REGDB_VERSION_V2);

done:
  talloc_free(mem_ctx);
  return werr;
}

static bool tdb_data_read_uint32(TDB_DATA *buf, uint32_t *result)
{
  const size_t len = sizeof(uint32_t);
  if (buf->dsize >= len) {
    *result = IVAL(buf->dptr, 0);
    buf->dptr += len;
    buf->dsize -= len;
    return true;
  }
  return false;
}

static bool tdb_data_read_cstr(TDB_DATA *buf, char **result)
{
  const size_t len = strnlen((char*)buf->dptr, buf->dsize) + 1;
  if (buf->dsize >= len) {
    *result = (char*)buf->dptr;
    buf->dptr += len;
    buf->dsize -= len;
    return true;
  }
  return false;
}

static bool tdb_data_is_cstr(TDB_DATA d) {
  if (tdb_data_is_empty(d) || (d.dptr[d.dsize-1] != '\0')) {
    return false;
  }
  return strlen((char *)d.dptr) == (d.dsize-1);
}

static bool upgrade_v2_to_v3_check_subkeylist(struct db_context *db,
                const char *key,
                const char *subkey)
{
  static uint32_t zero = 0;
  static TDB_DATA empty_subkey_list = {
    .dptr = (unsigned char*)&zero,
    .dsize = sizeof(uint32_t),
  };
  bool success = false;
  char *path = talloc_asprintf(talloc_tos(), "%s\\%s", key, subkey);
  if (!strupper_m(path)) {
    goto done;
  }

  if (!dbwrap_exists(db, string_term_tdb_data(path))) {
    NTSTATUS status;

    DEBUG(10, ("regdb_upgrade_v2_to_v3: writing subkey list [%s]\n",
         path));

    status = dbwrap_store_bystring(db, path, empty_subkey_list,
                 TDB_INSERT);
    if (!NT_STATUS_IS_OK(status)) {
      DEBUG(0, ("regdb_upgrade_v2_to_v3: writing subkey list "
          "[%s] failed\n", path));
      goto done;
    }
  }
  success = true;
done:
  talloc_free(path);
  return success;
}

static bool upgrade_v2_to_v3_check_parent(struct db_context *db,
            const char *key)
{
  const char *sep = strrchr_m(key, '\\');
  if (sep != NULL) {
    char *pkey = talloc_strndup(talloc_tos(), key, sep-key);
    if (!dbwrap_exists(db, string_term_tdb_data(pkey))) {
      DEBUG(0, ("regdb_upgrade_v2_to_v3: missing subkey list "
          "[%s]\nrun \"net registry check\"\n", pkey));
    }
    talloc_free(pkey);
  }
  return true;
}


#define IS_EQUAL(d,s) (((d).dsize == strlen(s)+1) && \
           (strcmp((char*)(d).dptr, (s)) == 0))
#define STARTS_WITH(d,s) (((d).dsize > strlen(s)) &&     \
        (strncmp((char*)(d).dptr, (s), strlen(s)) == 0))
#define SSTR(d) (int)(d).dsize , (char*)(d).dptr


static int regdb_upgrade_v2_to_v3_fn(struct db_record *rec, void *private_data)
{
  struct db_context *db = (struct db_context *)private_data;
  TDB_DATA key = dbwrap_record_get_key(rec);
  TDB_DATA val = dbwrap_record_get_value(rec);

  if (tdb_data_is_empty(key)) {
    return 0;
  }

  if (db == NULL) {
    DEBUG(0, ("regdb_upgrade_v2_to_v3_fn: ERROR: "
        "NULL db context handed in via private_data\n"));
    return 1;
  }

  if (IS_EQUAL(key, REGDB_VERSION_KEYNAME) ||
      STARTS_WITH(key, REG_VALUE_PREFIX) ||
      STARTS_WITH(key, REG_SECDESC_PREFIX))
  {
    DEBUG(10, ("regdb_upgrade_v2_to_v3: skipping [%.*s]\n",
         SSTR(key)));
    return 0;
  }

  if (STARTS_WITH(key, REG_SORTED_SUBKEYS_PREFIX)) {
    NTSTATUS status;
    /* Delete the deprecated sorted subkeys cache. */

    DEBUG(10, ("regdb_upgrade_v2_to_v3: deleting [%.*s]\n",
         SSTR(key)));

    status = dbwrap_record_delete(rec);
    if (!NT_STATUS_IS_OK(status)) {
      DEBUG(0, ("regdb_upgrade_v2_to_v3: deleting [%.*s] "
          "failed!\n", SSTR(key)));
      return 1;
    }

    return 0;
  }

  if ( tdb_data_is_cstr(key) &&
       hive_info((char*)key.dptr) != NULL )
  {
    /*
     * Found a regular subkey list record.
     * Walk the list and create the list record for those
     * subkeys that don't already have one.
     */
    TDB_DATA pos = val;
    char *subkey, *path = (char*)key.dptr;
    uint32_t num_items, found_items = 0;


    DEBUG(10, ("regdb_upgrade_v2_to_v3: scanning subkeylist of "
         "[%s]\n", path));

    if (!tdb_data_read_uint32(&pos, &num_items)) {
      /* invalid or empty - skip */
      return 0;
    }

    while (tdb_data_read_cstr(&pos, &subkey)) {
      found_items++;

      if (!upgrade_v2_to_v3_check_subkeylist(db, path, subkey))
      {
        return 1;
      }

      if (!upgrade_v2_to_v3_check_parent(db, path)) {
        return 1;
      }
    }
    if (found_items != num_items) {
      DEBUG(0, ("regdb_upgrade_v2_to_v3: inconsistent subkey "
          "list [%s]\nrun \"net registry check\"\n",
          path));
    }
  } else {
    DEBUG(10, ("regdb_upgrade_v2_to_v3: skipping invalid [%.*s]\n"
         "run \"net registry check\"\n", SSTR(key)));
  }

  return 0;
}

static WERROR regdb_upgrade_v2_to_v3(struct db_context *db)
{
  NTSTATUS status;
  WERROR werr;

  status = dbwrap_traverse(db, regdb_upgrade_v2_to_v3_fn, db, NULL);
  if (!NT_STATUS_IS_OK(status)) {
    werr = WERR_REGISTRY_IO_FAILED;
    goto done;
  }

  werr = regdb_store_regdb_version(db, REGDB_VERSION_V3);

done:
  return werr;
}

/***********************************************************************
 Open the registry database
 ***********************************************************************/

WERROR regdb_init(void)
{
  int32_t vers_id;
  WERROR werr;
  NTSTATUS status;
  char *db_path;

  if (regdb) {
    DEBUG(10, ("regdb_init: incrementing refcount (%d->%d)\n",
         regdb_refcount, regdb_refcount+1));
    regdb_refcount++;
    return WERR_OK;
  }

        /*
         * Clustered Samba can only work as root because we need messaging to
         * talk to ctdb which only works as root.
         */
        if (!uid_wrapper_enabled() && lp_clustering() && geteuid() != 0) {
                DBG_ERR("Cluster mode requires running as root.\n");
    return WERR_ACCESS_DENIED;
        }

  db_path = state_path(talloc_tos(), "registry.tdb");
  if (db_path == NULL) {
    return WERR_NOT_ENOUGH_MEMORY;
  }

  regdb = db_open(NULL, db_path, 0,
      REG_TDB_FLAGS, O_RDWR, 0600,
      DBWRAP_LOCK_ORDER_1, REG_DBWRAP_FLAGS);
  if (!regdb) {
    regdb = db_open(NULL, db_path, 0,
        REG_TDB_FLAGS, O_RDWR|O_CREAT, 0600,
        DBWRAP_LOCK_ORDER_1, REG_DBWRAP_FLAGS);
    if (!regdb) {
      werr = ntstatus_to_werror(map_nt_error_from_unix(errno));
      DEBUG(1,("regdb_init: Failed to open registry %s (%s)\n",
        db_path, strerror(errno) ));
      TALLOC_FREE(db_path);
      return werr;
    }

    werr = regdb_store_regdb_version(regdb, REGDB_CODE_VERSION);
    if (!W_ERROR_IS_OK(werr)) {
      DEBUG(1, ("regdb_init: Failed to store version: %s\n",
          win_errstr(werr)));
      TALLOC_FREE(db_path);
      return werr;
    }

    DEBUG(10,("regdb_init: Successfully created registry tdb\n"));
  }
  TALLOC_FREE(db_path);

  regdb_refcount = 1;
  DEBUG(10, ("regdb_init: registry db opened. refcount reset (%d)\n",
       regdb_refcount));

  status = dbwrap_fetch_int32_bystring(regdb, REGDB_VERSION_KEYNAME,
               &vers_id);
  if (!NT_STATUS_IS_OK(status)) {
    DBG_DEBUG("Reading registry version failed: %s, "
        "initializing to version %d\n",
        nt_errstr(status), REGDB_VERSION_V1);

    /*
     * There was a regdb format version prior to version 1
     * which did not store a INFO/version key. The format
     * of this version was identical to version 1 except for
     * the lack of the sorted subkey cache records.
     * Since these are disposable, we can safely assume version
     * 1 if no INFO/version key is found and run the db through
     * the whole chain of upgrade. If the database was not
     * initialized, this does not harm. If it was the unversioned
     * version ("0"), then it do the right thing with the records.
     */
    werr = regdb_store_regdb_version(regdb, REGDB_VERSION_V1);
    if (!W_ERROR_IS_OK(werr)) {
      return werr;
    }
    vers_id = REGDB_VERSION_V1;
  }

  if (vers_id == REGDB_CODE_VERSION) {
    return WERR_OK;
  }

  if (vers_id > REGDB_CODE_VERSION || vers_id == 0) {
    DEBUG(0, ("regdb_init: unknown registry version %d "
        "(code version = %d), refusing initialization\n",
        vers_id, REGDB_CODE_VERSION));
    return WERR_CAN_NOT_COMPLETE;
  }

  if (dbwrap_transaction_start(regdb) != 0) {
    return WERR_REGISTRY_IO_FAILED;
  }

  if (vers_id == REGDB_VERSION_V1) {
    DEBUG(10, ("regdb_init: upgrading registry from version %d "
         "to %d\n", REGDB_VERSION_V1, REGDB_VERSION_V2));

    werr = regdb_upgrade_v1_to_v2(regdb);
    if (!W_ERROR_IS_OK(werr)) {
      dbwrap_transaction_cancel(regdb);
      return werr;
    }

    vers_id = REGDB_VERSION_V2;
  }

  if (vers_id == REGDB_VERSION_V2) {
    DEBUG(10, ("regdb_init: upgrading registry from version %d "
         "to %d\n", REGDB_VERSION_V2, REGDB_VERSION_V3));

    werr = regdb_upgrade_v2_to_v3(regdb);
    if (!W_ERROR_IS_OK(werr)) {
      dbwrap_transaction_cancel(regdb);
      return werr;
    }

    vers_id = REGDB_VERSION_V3;
  }

  /* future upgrade code should go here */

  if (dbwrap_transaction_commit(regdb) != 0) {
    return WERR_REGISTRY_IO_FAILED;
  }

  return WERR_OK;
}

/***********************************************************************
 Open the registry.  Must already have been initialized by regdb_init()
 ***********************************************************************/

WERROR regdb_open( void )
{
  WERROR result;
  char *db_path = NULL;
  int saved_errno;

  if ( regdb ) {
    DEBUG(10, ("regdb_open: incrementing refcount (%d->%d)\n",
         regdb_refcount, regdb_refcount+1));
    regdb_refcount++;
    result = WERR_OK;
    goto done;
  }

  db_path = state_path(talloc_tos(), "registry.tdb");
  if (db_path == NULL) {
    result = WERR_NOT_ENOUGH_MEMORY;
    goto done;
  }

  become_root();

  regdb = db_open(NULL, db_path, 0,
      REG_TDB_FLAGS, O_RDWR, 0600,
      DBWRAP_LOCK_ORDER_1, REG_DBWRAP_FLAGS);
  saved_errno = errno;
  unbecome_root();
  if ( !regdb ) {
    result = ntstatus_to_werror(map_nt_error_from_unix(saved_errno));
    DEBUG(0,("regdb_open: Failed to open %s! (%s)\n",
       db_path, strerror(saved_errno)));
    goto done;
  }

  regdb_refcount = 1;
  DEBUG(10, ("regdb_open: registry db opened. refcount reset (%d)\n",
       regdb_refcount));

  result = WERR_OK;
done:
  TALLOC_FREE(db_path);
  return result;
}

/***********************************************************************
 ***********************************************************************/

int regdb_close( void )
{
  if (regdb_refcount == 0) {
    return 0;
  }

  regdb_refcount--;

  DEBUG(10, ("regdb_close: decrementing refcount (%d->%d)\n",
       regdb_refcount+1, regdb_refcount));

  if ( regdb_refcount > 0 )
    return 0;

  SMB_ASSERT( regdb_refcount >= 0 );

  TALLOC_FREE(regdb);
  return 0;
}

WERROR regdb_transaction_start(void)
{
  return (dbwrap_transaction_start(regdb) == 0) ?
    WERR_OK : WERR_REGISTRY_IO_FAILED;
}

WERROR regdb_transaction_commit(void)
{
  return (dbwrap_transaction_commit(regdb) == 0) ?
    WERR_OK : WERR_REGISTRY_IO_FAILED;
}

WERROR regdb_transaction_cancel(void)
{
  return (dbwrap_transaction_cancel(regdb) == 0) ?
    WERR_OK : WERR_REGISTRY_IO_FAILED;
}

/***********************************************************************
 return the tdb sequence number of the registry tdb.
 this is an indicator for the content of the registry
 having changed. it will change upon regdb_init, too, though.
 ***********************************************************************/
int regdb_get_seqnum(void)
{
  return dbwrap_get_seqnum(regdb);
}


static WERROR regdb_delete_key_with_prefix(struct db_context *db,
             const char *keyname,
             const char *prefix)
{
  char *path;
  WERROR werr = WERR_NOT_ENOUGH_MEMORY;
  TALLOC_CTX *mem_ctx = talloc_stackframe();

  if (keyname == NULL) {
    werr = WERR_INVALID_PARAMETER;
    goto done;
  }

  if (prefix == NULL) {
    path = discard_const_p(char, keyname);
  } else {
    path = talloc_asprintf(mem_ctx, "%s\\%s", prefix, keyname);
    if (path == NULL) {
      goto done;
    }
  }

  path = normalize_reg_path(mem_ctx, path);
  if (path == NULL) {
    goto done;
  }

  werr = ntstatus_to_werror(dbwrap_purge_bystring(db, path));

done:
  talloc_free(mem_ctx);
  return werr;
}


static WERROR regdb_delete_values(struct db_context *db, const char *keyname)
{
  return regdb_delete_key_with_prefix(db, keyname, REG_VALUE_PREFIX);
}

static WERROR regdb_delete_secdesc(struct db_context *db, const char *keyname)
{
  return regdb_delete_key_with_prefix(db, keyname, REG_SECDESC_PREFIX);
}

static WERROR regdb_delete_subkeylist(struct db_context *db, const char *keyname)
{
  return regdb_delete_key_with_prefix(db, keyname, NULL);
}


static WERROR regdb_delete_key_lists(struct db_context *db, const char *keyname)
{
  WERROR werr;

  werr = regdb_delete_values(db, keyname);
  if (!W_ERROR_IS_OK(werr)) {
    DEBUG(1, (__location__ " Deleting %s\\%s failed: %s\n",
        REG_VALUE_PREFIX, keyname, win_errstr(werr)));
    goto done;
  }

  werr = regdb_delete_secdesc(db, keyname);
  if (!W_ERROR_IS_OK(werr)) {
    DEBUG(1, (__location__ " Deleting %s\\%s failed: %s\n",
        REG_SECDESC_PREFIX, keyname, win_errstr(werr)));
    goto done;
  }

  werr = regdb_delete_subkeylist(db, keyname);
  if (!W_ERROR_IS_OK(werr)) {
    DEBUG(1, (__location__ " Deleting %s failed: %s\n",
        keyname, win_errstr(werr)));
    goto done;
  }

done:
  return werr;
}

/***********************************************************************
 Add subkey strings to the registry tdb under a defined key
 fmt is the same format as tdb_pack except this function only supports
 fstrings
 ***********************************************************************/

static WERROR regdb_store_keys_internal2(struct db_context *db,
           const char *key,
           struct regsubkey_ctr *ctr)
{
  TDB_DATA dbuf;
  uint8_t *buffer = NULL;
  uint32_t i = 0;
  uint32_t len, buflen;
  uint32_t num_subkeys = regsubkey_ctr_numkeys(ctr);
  char *keyname = NULL;
  TALLOC_CTX *ctx = talloc_stackframe();
  WERROR werr;

  if (!key) {
    werr = WERR_INVALID_PARAMETER;
    goto done;
  }

  keyname = talloc_strdup(ctx, key);
  if (!keyname) {
    werr = WERR_NOT_ENOUGH_MEMORY;
    goto done;
  }

  keyname = normalize_reg_path(ctx, keyname);
  if (!keyname) {
    werr = WERR_NOT_ENOUGH_MEMORY;
    goto done;
  }

  /* allocate some initial memory */

  buffer = (uint8_t *)SMB_MALLOC(1024);
  if (buffer == NULL) {
    werr = WERR_NOT_ENOUGH_MEMORY;
    goto done;
  }
  buflen = 1024;
  len = 0;

  /* store the number of subkeys */

  len += tdb_pack(buffer+len, buflen-len, "d", num_subkeys);

  /* pack all the strings */

  for (i=0; i<num_subkeys; i++) {
    size_t thistime;

    thistime = tdb_pack(buffer+len, buflen-len, "f",
            regsubkey_ctr_specific_key(ctr, i));
    if (len+thistime > buflen) {
      size_t thistime2;
      /*
       * tdb_pack hasn't done anything because of the short
       * buffer, allocate extra space.
       */
      buffer = SMB_REALLOC_ARRAY(buffer, uint8_t,
               (len+thistime)*2);
      if(buffer == NULL) {
        DEBUG(0, ("regdb_store_keys: Failed to realloc "
            "memory of size [%u]\n",
            (unsigned int)(len+thistime)*2));
        werr = WERR_NOT_ENOUGH_MEMORY;
        goto done;
      }
      buflen = (len+thistime)*2;
      thistime2 = tdb_pack(
        buffer+len, buflen-len, "f",
        regsubkey_ctr_specific_key(ctr, i));
      if (thistime2 != thistime) {
        DEBUG(0, ("tdb_pack failed\n"));
        werr = WERR_CAN_NOT_COMPLETE;
        goto done;
      }
    }
    len += thistime;
  }

  /* finally write out the data */

  dbuf.dptr = buffer;
  dbuf.dsize = len;
  werr = ntstatus_to_werror(dbwrap_store_bystring(db, keyname, dbuf,
              TDB_REPLACE));

done:
  TALLOC_FREE(ctx);
  SAFE_FREE(buffer);
  return werr;
}

/**
 * Utility function to store a new empty list of
 * subkeys of given key specified as parent and subkey name
 * (thereby creating the key).
 * If the parent keyname is NULL, then the "subkey" is
 * interpreted as a base key.
 * If the subkey list does already exist, it is not modified.
 *
 * Must be called from within a transaction.
 */
static WERROR regdb_store_subkey_list(struct db_context *db, const char *parent,
              const char *key)
{
  WERROR werr;
  char *path = NULL;
  struct regsubkey_ctr *subkeys = NULL;
  TALLOC_CTX *frame = talloc_stackframe();

  if (parent == NULL) {
    path = talloc_strdup(frame, key);
  } else {
    path = talloc_asprintf(frame, "%s\\%s", parent, key);
  }
  if (!path) {
    werr = WERR_NOT_ENOUGH_MEMORY;
    goto done;
  }

  werr = regsubkey_ctr_init(frame, &subkeys);
  W_ERROR_NOT_OK_GOTO_DONE(werr);

  werr = regdb_fetch_keys_internal(db, path, subkeys);
  if (W_ERROR_IS_OK(werr)) {
    /* subkey list exists already - don't modify */
    goto done;
  }

  werr = regsubkey_ctr_reinit(subkeys);
  W_ERROR_NOT_OK_GOTO_DONE(werr);

  /* create a record with 0 subkeys */
  werr = regdb_store_keys_internal2(db, path, subkeys);
  if (!W_ERROR_IS_OK(werr)) {
    DEBUG(0, ("regdb_store_keys: Failed to store new record for "
        "key [%s]: %s\n", path, win_errstr(werr)));
    goto done;
  }

done:
  talloc_free(frame);
  return werr;
}

/***********************************************************************
 Store the new subkey record and create any child key records that
 do not currently exist
 ***********************************************************************/

struct regdb_store_keys_context {
  const char *key;
  struct regsubkey_ctr *ctr;
};

static NTSTATUS regdb_store_keys_action(struct db_context *db,
          void *private_data)
{
  struct regdb_store_keys_context *store_ctx;
  WERROR werr;
  int num_subkeys, i;
  char *path = NULL;
  struct regsubkey_ctr *old_subkeys = NULL;
  char *oldkeyname = NULL;
  TALLOC_CTX *mem_ctx = talloc_stackframe();

  store_ctx = (struct regdb_store_keys_context *)private_data;

  /*
   * Re-fetch the old keys inside the transaction
   */

  werr = regsubkey_ctr_init(mem_ctx, &old_subkeys);
  W_ERROR_NOT_OK_GOTO_DONE(werr);

  werr = regdb_fetch_keys_internal(db, store_ctx->key, old_subkeys);
  if (!W_ERROR_IS_OK(werr) &&
      !W_ERROR_EQUAL(werr, WERR_NOT_FOUND))
  {
    goto done;
  }

  /*
   * Make the store operation as safe as possible without transactions:
   *
   * (1) For each subkey removed from ctr compared with old_subkeys:
   *
   *     (a) First delete the value db entry.
   *
   *     (b) Next delete the secdesc db record.
   *
   *     (c) Then delete the subkey list entry.
   *
   * (2) Now write the list of subkeys of the parent key,
   *     deleting removed entries and adding new ones.
   *
   * (3) Finally create the subkey list entries for the added keys.
   *
   * This way if we crash half-way in between deleting the subkeys
   * and storing the parent's list of subkeys, no old data can pop up
   * out of the blue when re-adding keys later on.
   */

  /* (1) delete removed keys' lists (values/secdesc/subkeys) */

  num_subkeys = regsubkey_ctr_numkeys(old_subkeys);
  for (i=0; i<num_subkeys; i++) {
    oldkeyname = regsubkey_ctr_specific_key(old_subkeys, i);

    if (regsubkey_ctr_key_exists(store_ctx->ctr, oldkeyname)) {
      /*
       * It's still around, don't delete
       */
      continue;
    }

    path = talloc_asprintf(mem_ctx, "%s\\%s", store_ctx->key,
               oldkeyname);
    if (!path) {
      werr = WERR_NOT_ENOUGH_MEMORY;
      goto done;
    }

    werr = regdb_delete_key_lists(db, path);
    W_ERROR_NOT_OK_GOTO_DONE(werr);

    TALLOC_FREE(path);
  }

  TALLOC_FREE(old_subkeys);

  /* (2) store the subkey list for the parent */

  werr = regdb_store_keys_internal2(db, store_ctx->key, store_ctx->ctr);
  if (!W_ERROR_IS_OK(werr)) {
    DEBUG(0,("regdb_store_keys: Failed to store new subkey list "
       "for parent [%s]: %s\n", store_ctx->key,
       win_errstr(werr)));
    goto done;
  }

  /* (3) now create records for any subkeys that don't already exist */

  num_subkeys = regsubkey_ctr_numkeys(store_ctx->ctr);

  for (i=0; i<num_subkeys; i++) {
    const char *subkey;

    subkey = regsubkey_ctr_specific_key(store_ctx->ctr, i);

    werr = regdb_store_subkey_list(db, store_ctx->key, subkey);
    W_ERROR_NOT_OK_GOTO_DONE(werr);
  }

  /*
   * Update the seqnum in the container to possibly
   * prevent next read from going to disk
   */
  werr = regsubkey_ctr_set_seqnum(store_ctx->ctr, dbwrap_get_seqnum(db));

done:
  talloc_free(mem_ctx);
  return werror_to_ntstatus(werr);
}

static bool regdb_store_keys_internal(struct db_context *db, const char *key,
              struct regsubkey_ctr *ctr)
{
  int num_subkeys, old_num_subkeys, i;
  struct regsubkey_ctr *old_subkeys = NULL;
  TALLOC_CTX *ctx = talloc_stackframe();
  WERROR werr;
  bool ret = false;
  struct regdb_store_keys_context store_ctx;

  if (!regdb_key_exists(db, key)) {
    goto done;
  }

  /*
   * fetch a list of the old subkeys so we can determine if anything has
   * changed
   */

  werr = regsubkey_ctr_init(ctx, &old_subkeys);
  if (!W_ERROR_IS_OK(werr)) {
    DEBUG(0,("regdb_store_keys: talloc() failure!\n"));
    goto done;
  }

  werr = regdb_fetch_keys_internal(db, key, old_subkeys);
  if (!W_ERROR_IS_OK(werr) &&
      !W_ERROR_EQUAL(werr, WERR_NOT_FOUND))
  {
    goto done;
  }

  num_subkeys = regsubkey_ctr_numkeys(ctr);
  old_num_subkeys = regsubkey_ctr_numkeys(old_subkeys);
  if ((num_subkeys && old_num_subkeys) &&
      (num_subkeys == old_num_subkeys)) {

    for (i = 0; i < num_subkeys; i++) {
      if (strcmp(regsubkey_ctr_specific_key(ctr, i),
           regsubkey_ctr_specific_key(old_subkeys, i))
          != 0)
      {
        break;
      }
    }
    if (i == num_subkeys) {
      /*
       * Nothing changed, no point to even start a tdb
       * transaction
       */

      ret = true;
      goto done;
    }
  }

  TALLOC_FREE(old_subkeys);

  store_ctx.key = key;
  store_ctx.ctr = ctr;

  werr = regdb_trans_do(db,
            regdb_store_keys_action,
            &store_ctx);

  ret = W_ERROR_IS_OK(werr);

done:
  TALLOC_FREE(ctx);

  return ret;
}

static bool regdb_store_keys(const char *key, struct regsubkey_ctr *ctr)
{
  return regdb_store_keys_internal(regdb, key, ctr);
}

/**
 * create a subkey of a given key
 */

struct regdb_create_subkey_context {
  const char *key;
  const char *subkey;
};

static NTSTATUS regdb_create_subkey_action(struct db_context *db,
             void *private_data)
{
  WERROR werr;
  struct regdb_create_subkey_context *create_ctx;
  struct regsubkey_ctr *subkeys;
  TALLOC_CTX *mem_ctx = talloc_stackframe();

  create_ctx = (struct regdb_create_subkey_context *)private_data;

  werr = regsubkey_ctr_init(mem_ctx, &subkeys);
  W_ERROR_NOT_OK_GOTO_DONE(werr);

  werr = regdb_fetch_keys_internal(db, create_ctx->key, subkeys);
  W_ERROR_NOT_OK_GOTO_DONE(werr);

  werr = regsubkey_ctr_addkey(subkeys, create_ctx->subkey);
  W_ERROR_NOT_OK_GOTO_DONE(werr);

  werr = regdb_store_keys_internal2(db, create_ctx->key, subkeys);
  if (!W_ERROR_IS_OK(werr)) {
    DEBUG(0, (__location__ " failed to store new subkey list for "
       "parent key %s: %s\n", create_ctx->key,
       win_errstr(werr)));
  }

  werr = regdb_store_subkey_list(db, create_ctx->key, create_ctx->subkey);

done:
  talloc_free(mem_ctx);
  return werror_to_ntstatus(werr);
}

static WERROR regdb_create_subkey_internal(struct db_context *db,
             const char *key,
             const char *subkey)
{
  WERROR werr;
  struct regsubkey_ctr *subkeys;
  TALLOC_CTX *mem_ctx = talloc_stackframe();
  struct regdb_create_subkey_context create_ctx;

  if (!regdb_key_exists(db, key)) {
    werr = WERR_NOT_FOUND;
    goto done;
  }

  werr = regsubkey_ctr_init(mem_ctx, &subkeys);
  W_ERROR_NOT_OK_GOTO_DONE(werr);

  werr = regdb_fetch_keys_internal(db, key, subkeys);
  W_ERROR_NOT_OK_GOTO_DONE(werr);

  if (regsubkey_ctr_key_exists(subkeys, subkey)) {
    char *newkey;

    newkey = talloc_asprintf(mem_ctx, "%s\\%s", key, subkey);
    if (newkey == NULL) {
      werr = WERR_NOT_ENOUGH_MEMORY;
      goto done;
    }

    if (regdb_key_exists(db, newkey)) {
      werr = WERR_OK;
      goto done;
    }
  }

  talloc_free(subkeys);

  create_ctx.key = key;
  create_ctx.subkey = subkey;

  werr = regdb_trans_do(db,
            regdb_create_subkey_action,
            &create_ctx);

done:
  talloc_free(mem_ctx);
  return werr;
}

static WERROR regdb_create_subkey(const char *key, const char *subkey)
{
  return regdb_create_subkey_internal(regdb, key, subkey);
}

/**
 * create a base key
 */

struct regdb_create_basekey_context {
  const char *key;
};

static NTSTATUS regdb_create_basekey_action(struct db_context *db,
              void *private_data)
{
  WERROR werr;
  struct regdb_create_basekey_context *create_ctx;

  create_ctx = (struct regdb_create_basekey_context *)private_data;

  werr = regdb_store_subkey_list(db, NULL, create_ctx->key);

  return werror_to_ntstatus(werr);
}

static WERROR regdb_create_basekey(struct db_context *db, const char *key)
{
  WERROR werr;
  struct regdb_create_subkey_context create_ctx;

  create_ctx.key = key;

  werr = regdb_trans_do(db,
            regdb_create_basekey_action,
            &create_ctx);

  return werr;
}

/**
 * create a subkey of a given key
 */

struct regdb_delete_subkey_context {
  const char *key;
  const char *subkey;
  const char *path;
  bool lazy;
};

static NTSTATUS regdb_delete_subkey_action(struct db_context *db,
             void *private_data)
{
  WERROR werr;
  struct regdb_delete_subkey_context *delete_ctx;
  struct regsubkey_ctr *subkeys;
  TALLOC_CTX *mem_ctx = talloc_stackframe();

  delete_ctx = (struct regdb_delete_subkey_context *)private_data;

  werr = regdb_delete_key_lists(db, delete_ctx->path);
  W_ERROR_NOT_OK_GOTO_DONE(werr);

  if (delete_ctx->lazy) {
    goto done;
  }

  werr = regsubkey_ctr_init(mem_ctx, &subkeys);
  W_ERROR_NOT_OK_GOTO_DONE(werr);

  werr = regdb_fetch_keys_internal(db, delete_ctx->key, subkeys);
  W_ERROR_NOT_OK_GOTO_DONE(werr);

  werr = regsubkey_ctr_delkey(subkeys, delete_ctx->subkey);
  W_ERROR_NOT_OK_GOTO_DONE(werr);

  werr = regdb_store_keys_internal2(db, delete_ctx->key, subkeys);
  if (!W_ERROR_IS_OK(werr)) {
    DEBUG(0, (__location__ " failed to store new subkey_list for "
       "parent key %s: %s\n", delete_ctx->key,
       win_errstr(werr)));
  }

done:
  talloc_free(mem_ctx);
  return werror_to_ntstatus(werr);
}

static WERROR regdb_delete_subkey(const char *key, const char *subkey, bool lazy)
{
  WERROR werr;
  char *path;
  struct regdb_delete_subkey_context delete_ctx;
  TALLOC_CTX *mem_ctx = talloc_stackframe();

  if (!regdb_key_exists(regdb, key)) {
    werr = WERR_NOT_FOUND;
    goto done;
  }

  path = talloc_asprintf(mem_ctx, "%s\\%s", key, subkey);
  if (path == NULL) {
    werr = WERR_NOT_ENOUGH_MEMORY;
    goto done;
  }

  if (!regdb_key_exists(regdb, path)) {
    werr = WERR_OK;
    goto done;
  }

  delete_ctx.key = key;
  delete_ctx.subkey = subkey;
  delete_ctx.path = path;
  delete_ctx.lazy = lazy;

  werr = regdb_trans_do(regdb,
            regdb_delete_subkey_action,
            &delete_ctx);

done:
  talloc_free(mem_ctx);
  return werr;
}

static TDB_DATA regdb_fetch_key_internal(struct db_context *db,
           TALLOC_CTX *mem_ctx, const char *key)
{
  char *path = NULL;
  TDB_DATA data;
  NTSTATUS status;

  path = normalize_reg_path(mem_ctx, key);
  if (!path) {
    return make_tdb_data(NULL, 0);
  }

  status = dbwrap_fetch_bystring(db, mem_ctx, path, &data);
  if (!NT_STATUS_IS_OK(status)) {
    data = tdb_null;
  }

  TALLOC_FREE(path);
  return data;
}


/**
 * Check for the existence of a key.
 *
 * Existence of a key is authoritatively defined by
 * the existence of the record that contains the list
 * of its subkeys.
 *
 * Return false, if the record does not match the correct
 * structure of an initial 4-byte counter and then a
 * list of the corresponding number of zero-terminated
 * strings.
 */
static bool regdb_key_exists(struct db_context *db, const char *key)
{
  TALLOC_CTX *mem_ctx = talloc_stackframe();
  TDB_DATA value;
  bool ret = false;
  char *path;
  uint32_t buflen;
  const char *buf;
  uint32_t num_items, i;
  int32_t len;

  if (key == NULL) {
    goto done;
  }

  path = normalize_reg_path(mem_ctx, key);
  if (path == NULL) {
    DEBUG(0, ("out of memory! (talloc failed)\n"));
    goto done;
  }

  if (*path == '\0') {
    goto done;
  }

  value = regdb_fetch_key_internal(db, mem_ctx, path);
  if (value.dptr == NULL) {
    goto done;
  }

  if (value.dsize == 0) {
    DEBUG(10, ("regdb_key_exists: subkeylist-record for key "
        "[%s] is empty: Could be a deleted record in a "
        "clustered (ctdb) environment?\n",
        path));
    goto done;
  }

  len = tdb_unpack(value.dptr, value.dsize, "d", &num_items);
  if (len == (int32_t)-1) {
    DEBUG(1, ("regdb_key_exists: ERROR: subkeylist-record for key "
        "[%s] is invalid: Could not parse initial 4-byte "
        "counter. record data length is %u.\n",
        path, (unsigned int)value.dsize));
    goto done;
  }

  /*
   * Note: the tdb_unpack check above implies that len <= value.dsize
   */
  buflen = value.dsize - len;
  buf = (const char *)value.dptr + len;

  for (i = 0; i < num_items; i++) {
    if (buflen == 0) {
      break;
    }
    len = strnlen(buf, buflen) + 1;
    if (buflen < len) {
      DEBUG(1, ("regdb_key_exists: ERROR: subkeylist-record "
          "for key [%s] is corrupt: %u items expected, "
          "item number %u is not zero terminated.\n",
          path, num_items, i+1));
      goto done;
    }

    buf += len;
    buflen -= len;
  }

  if (buflen > 0) {
    DEBUG(1, ("regdb_key_exists: ERROR: subkeylist-record for key "
        "[%s] is corrupt: %u items expected and found, but "
        "the record contains additional %u bytes\n",
        path, num_items, buflen));
    goto done;
  }

  if (i < num_items) {
    DEBUG(1, ("regdb_key_exists: ERROR: subkeylist-record for key "
        "[%s] is corrupt: %u items expected, but only %u "
        "items found.\n",
        path, num_items, i+1));
    goto done;
  }

  ret = true;

done:
  TALLOC_FREE(mem_ctx);
  return ret;
}


/***********************************************************************
 Retrieve an array of strings containing subkeys.  Memory should be
 released by the caller.
 ***********************************************************************/

static WERROR regdb_fetch_keys_internal(struct db_context *db, const char *key,
          struct regsubkey_ctr *ctr)
{
  WERROR werr;
  uint32_t num_items;
  uint8_t *buf;
  uint32_t buflen, len;
  uint32_t i;
  fstring subkeyname;
  TALLOC_CTX *frame = talloc_stackframe();
  TDB_DATA value;
  int seqnum[2], count;

  DEBUG(11,("regdb_fetch_keys: Enter key => [%s]\n", key ? key : "NULL"));

  if (!regdb_key_exists(db, key)) {
    DEBUG(10, ("key [%s] not found\n", key));
    werr = WERR_NOT_FOUND;
    goto done;
  }

  werr = regsubkey_ctr_reinit(ctr);
  W_ERROR_NOT_OK_GOTO_DONE(werr);

  count = 0;
  ZERO_STRUCT(value);
  seqnum[0] = dbwrap_get_seqnum(db);

  do {
    count++;
    TALLOC_FREE(value.dptr);
    value = regdb_fetch_key_internal(db, frame, key);
    seqnum[count % 2] = dbwrap_get_seqnum(db);

  } while (seqnum[0] != seqnum[1]);

  if (count > 1) {
    DEBUG(5, ("regdb_fetch_keys_internal: it took %d attempts to "
        "fetch key '%s' with constant seqnum\n",
        count, key));
  }

  werr = regsubkey_ctr_set_seqnum(ctr, seqnum[0]);
  if (!W_ERROR_IS_OK(werr)) {
    goto done;
  }

  if (value.dsize == 0 || value.dptr == NULL) {
    DEBUG(10, ("regdb_fetch_keys: no subkeys found for key [%s]\n",
         key));
    goto done;
  }

  buf = value.dptr;
  buflen = value.dsize;
  len = tdb_unpack( buf, buflen, "d", &num_items);
  if (len == (uint32_t)-1) {
    werr = WERR_NOT_FOUND;
    goto done;
  }

  for (i=0; i<num_items; i++) {
    int this_len;

    this_len = tdb_unpack(buf+len, buflen-len, "f", subkeyname);
    if (this_len == -1) {
      DBG_WARNING("Invalid registry data, "
            "tdb_unpack failed\n");
      werr = WERR_INTERNAL_DB_CORRUPTION;
      goto done;
    }
    len += this_len;
    if (len < this_len) {
      DBG_WARNING("Invalid registry data, "
            "integer overflow\n");
      werr = WERR_INTERNAL_DB_CORRUPTION;
      goto done;
    }

    werr = regsubkey_ctr_addkey(ctr, subkeyname);
    if (!W_ERROR_IS_OK(werr)) {
      DEBUG(5, ("regdb_fetch_keys: regsubkey_ctr_addkey "
          "failed: %s\n", win_errstr(werr)));
      num_items = 0;
      goto done;
    }
  }

  DEBUG(11,("regdb_fetch_keys: Exit [%d] items\n", num_items));

done:
  TALLOC_FREE(frame);
  return werr;
}

static int regdb_fetch_keys(const char *key, struct regsubkey_ctr *ctr)
{
  WERROR werr;

  werr = regdb_fetch_keys_internal(regdb, key, ctr);
  if (!W_ERROR_IS_OK(werr)) {
    return -1;
  }

  return regsubkey_ctr_numkeys(ctr);
}

/****************************************************************************
 Unpack a list of registry values frem the TDB
 ***************************************************************************/

static int regdb_unpack_values(struct regval_ctr *values,
             uint8_t *buf,
             size_t buflen)
{
  int this_len;
  size_t    len = 0;
  uint32_t  type;
  fstring valuename;
  uint32_t  size;
  uint8_t   *data_p;
  uint32_t  num_values = 0;
  uint32_t  i;

  /* loop and unpack the rest of the registry values */

  this_len = tdb_unpack(buf, buflen, "d", &num_values);
  if (this_len == -1) {
    DBG_WARNING("Invalid registry data, "
          "tdb_unpack failed\n");
    return -1;
  }
  len = this_len;

  for ( i=0; i<num_values; i++ ) {
    /* unpack the next regval */

    type = REG_NONE;
    size = 0;
    data_p = NULL;
    valuename[0] = '\0';
    this_len = tdb_unpack(buf+len, buflen-len, "fdB",
              valuename,
              &type,
              &size,
              &data_p);
    if (this_len == -1) {
      DBG_WARNING("Invalid registry data, "
            "tdb_unpack failed\n");
      return -1;
    }
    len += this_len;
    if (len < (size_t)this_len) {
      DBG_WARNING("Invalid registry data, "
            "integer overflow\n");
      return -1;
    }

    regval_ctr_addvalue(values, valuename, type,
        (uint8_t *)data_p, size);
    SAFE_FREE(data_p); /* 'B' option to tdb_unpack does a malloc() */

    DEBUG(10, ("regdb_unpack_values: value[%d]: name[%s] len[%d]\n",
         i, valuename, size));
  }

  return len;
}

/****************************************************************************
 Pack all values in all printer keys
 ***************************************************************************/

static int regdb_pack_values(struct regval_ctr *values, uint8_t *buf, int buflen)
{
  int     len = 0;
  int     i;
  struct regval_blob  *val;
  int   num_values;

  if ( !values )
    return 0;

  num_values = regval_ctr_numvals( values );

  /* pack the number of values first */

  len += tdb_pack( buf+len, buflen-len, "d", num_values );

  /* loop over all values */

  for ( i=0; i<num_values; i++ ) {
    val = regval_ctr_specific_value( values, i );
    len += tdb_pack(buf+len, buflen-len, "fdB",
        regval_name(val),
        regval_type(val),
        regval_size(val),
        regval_data_p(val) );
  }

  return len;
}

/***********************************************************************
 Retrieve an array of strings containing subkeys.  Memory should be
 released by the caller.
 ***********************************************************************/

static int regdb_fetch_values_internal(struct db_context *db, const char* key,
               struct regval_ctr *values)
{
  char *keystr = NULL;
  TALLOC_CTX *ctx = talloc_stackframe();
  int ret = 0;
  TDB_DATA value;
  WERROR werr;
  int seqnum[2], count;

  DEBUG(10,("regdb_fetch_values: Looking for values of key [%s]\n", key));

  if (!regdb_key_exists(db, key)) {
    DEBUG(10, ("regb_fetch_values: key [%s] does not exist\n",
         key));
    ret = -1;
    goto done;
  }

  keystr = talloc_asprintf(ctx, "%s\\%s", REG_VALUE_PREFIX, key);
  if (!keystr) {
    goto done;
  }

  ZERO_STRUCT(value);
  count = 0;
  seqnum[0] = dbwrap_get_seqnum(db);

  do {
    count++;
    TALLOC_FREE(value.dptr);
    value = regdb_fetch_key_internal(db, ctx, keystr);
    seqnum[count % 2] = dbwrap_get_seqnum(db);
  } while (seqnum[0] != seqnum[1]);

  if (count > 1) {
    DEBUG(5, ("regdb_fetch_values_internal: it took %d attempts "
        "to fetch key '%s' with constant seqnum\n",
        count, key));
  }

  werr = regval_ctr_set_seqnum(values, seqnum[0]);
  if (!W_ERROR_IS_OK(werr)) {
    goto done;
  }

  if (!value.dptr) {
    /* all keys have zero values by default */
    goto done;
  }

  ret = regdb_unpack_values(values, value.dptr, value.dsize);
  if (ret == -1) {
    DBG_WARNING("regdb_unpack_values failed\n");
  }

  ret = regval_ctr_numvals(values);

done:
  TALLOC_FREE(ctx);
  return ret;
}

static int regdb_fetch_values(const char* key, struct regval_ctr *values)
{
  return regdb_fetch_values_internal(regdb, key, values);
}

static NTSTATUS regdb_store_values_internal(struct db_context *db,
              const char *key,
              struct regval_ctr *values)
{
  TDB_DATA old_data, data;
  char *keystr = NULL;
  TALLOC_CTX *ctx = talloc_stackframe();
  int len;
  NTSTATUS status;
  WERROR werr;

  DEBUG(10,("regdb_store_values: Looking for values of key [%s]\n", key));

  if (!regdb_key_exists(db, key)) {
    status = NT_STATUS_NOT_FOUND;
    goto done;
  }

  if (regval_ctr_numvals(values) == 0) {
    werr = regdb_delete_values(db, key);
    if (!W_ERROR_IS_OK(werr)) {
      status = werror_to_ntstatus(werr);
      goto done;
    }

    /*
     * update the seqnum in the cache to prevent the next read
     * from going to disk
     */
    werr = regval_ctr_set_seqnum(values, dbwrap_get_seqnum(db));
    status = werror_to_ntstatus(werr);
    goto done;
  }

  ZERO_STRUCT(data);

  len = regdb_pack_values(values, data.dptr, data.dsize);
  if (len <= 0) {
    DEBUG(0,("regdb_store_values: unable to pack values. len <= 0\n"));
    status = NT_STATUS_UNSUCCESSFUL;
    goto done;
  }

  data.dptr = talloc_array(ctx, uint8_t, len);
  data.dsize = len;

  len = regdb_pack_values(values, data.dptr, data.dsize);

  SMB_ASSERT( len == data.dsize );

  keystr = talloc_asprintf(ctx, "%s\\%s", REG_VALUE_PREFIX, key );
  if (!keystr) {
    status = NT_STATUS_NO_MEMORY;
    goto done;
  }
  keystr = normalize_reg_path(ctx, keystr);
  if (!keystr) {
    status = NT_STATUS_NO_MEMORY;
    goto done;
  }

  status = dbwrap_fetch_bystring(db, ctx, keystr, &old_data);

  if (NT_STATUS_IS_OK(status)
      && (old_data.dptr != NULL)
      && (old_data.dsize == data.dsize)
      && (memcmp(old_data.dptr, data.dptr, data.dsize) == 0))
  {
    status = NT_STATUS_OK;
    goto done;
  }

  status = dbwrap_trans_store_bystring(db, keystr, data, TDB_REPLACE);
  if (!NT_STATUS_IS_OK(status)) {
    DEBUG(0, ("regdb_store_values_internal: error storing: %s\n", nt_errstr(status)));
    goto done;
  }

  /*
   * update the seqnum in the cache to prevent the next read
   * from going to disk
   */
  werr = regval_ctr_set_seqnum(values, dbwrap_get_seqnum(db));
  status = werror_to_ntstatus(werr);

done:
  TALLOC_FREE(ctx);
  return status;
}

struct regdb_store_values_ctx {
  const char *key;
  struct regval_ctr *values;
};

static NTSTATUS regdb_store_values_action(struct db_context *db,
            void *private_data)
{
  NTSTATUS status;
  struct regdb_store_values_ctx *ctx =
    (struct regdb_store_values_ctx *)private_data;

  status = regdb_store_values_internal(db, ctx->key, ctx->values);

  return status;
}

static bool regdb_store_values(const char *key, struct regval_ctr *values)
{
  WERROR werr;
  struct regdb_store_values_ctx ctx;

  ctx.key = key;
  ctx.values = values;

  werr = regdb_trans_do(regdb, regdb_store_values_action, &ctx);

  return W_ERROR_IS_OK(werr);
}

static WERROR regdb_get_secdesc(TALLOC_CTX *mem_ctx, const char *key,
        struct security_descriptor **psecdesc)
{
  char *tdbkey;
  TDB_DATA data;
  NTSTATUS status;
  TALLOC_CTX *tmp_ctx = talloc_stackframe();
  WERROR err = WERR_OK;

  DEBUG(10, ("regdb_get_secdesc: Getting secdesc of key [%s]\n", key));

  if (!regdb_key_exists(regdb, key)) {
    err = WERR_FILE_NOT_FOUND;
    goto done;
  }

  tdbkey = talloc_asprintf(tmp_ctx, "%s\\%s", REG_SECDESC_PREFIX, key);
  if (tdbkey == NULL) {
    err = WERR_NOT_ENOUGH_MEMORY;
    goto done;
  }

  tdbkey = normalize_reg_path(tmp_ctx, tdbkey);
  if (tdbkey == NULL) {
    err = WERR_NOT_ENOUGH_MEMORY;
    goto done;
  }

  status = dbwrap_fetch_bystring(regdb, tmp_ctx, tdbkey, &data);
  if (!NT_STATUS_IS_OK(status)) {
    err = WERR_FILE_NOT_FOUND;
    goto done;
  }

  status = unmarshall_sec_desc(mem_ctx, (uint8_t *)data.dptr, data.dsize,
             psecdesc);

  if (NT_STATUS_EQUAL(status, NT_STATUS_NO_MEMORY)) {
    err = WERR_NOT_ENOUGH_MEMORY;
  } else if (!NT_STATUS_IS_OK(status)) {
    err = WERR_REGISTRY_CORRUPT;
  }

done:
  TALLOC_FREE(tmp_ctx);
  return err;
}

struct regdb_set_secdesc_ctx {
  const char *key;
  struct security_descriptor *secdesc;
};

static NTSTATUS regdb_set_secdesc_action(struct db_context *db,
           void *private_data)
{
  char *tdbkey;
  NTSTATUS status;
  TDB_DATA tdbdata;
  struct regdb_set_secdesc_ctx *ctx =
    (struct regdb_set_secdesc_ctx *)private_data;
  TALLOC_CTX *frame = talloc_stackframe();

  tdbkey = talloc_asprintf(frame, "%s\\%s", REG_SECDESC_PREFIX, ctx->key);
  if (tdbkey == NULL) {
    status = NT_STATUS_NO_MEMORY;
    goto done;
  }

  tdbkey = normalize_reg_path(frame, tdbkey);
  if (tdbkey == NULL) {
    status = NT_STATUS_NO_MEMORY;
    goto done;
  }

  if (ctx->secdesc == NULL) {
    /* assuming a delete */
    status = dbwrap_delete_bystring(db, tdbkey);
    goto done;
  }

  status = marshall_sec_desc(frame, ctx->secdesc, &tdbdata.dptr,
           &tdbdata.dsize);
  if (!NT_STATUS_IS_OK(status)) {
    goto done;
  }

  status = dbwrap_store_bystring(db, tdbkey, tdbdata, 0);

done:
  TALLOC_FREE(frame);
  return status;
}

static WERROR regdb_set_secdesc(const char *key,
        struct security_descriptor *secdesc)
{
  WERROR err;
  struct regdb_set_secdesc_ctx ctx;

  if (!regdb_key_exists(regdb, key)) {
    err = WERR_FILE_NOT_FOUND;
    goto done;
  }

  ctx.key = key;
  ctx.secdesc = secdesc;

  err = regdb_trans_do(regdb, regdb_set_secdesc_action, &ctx);

done:
  return err;
}

static bool regdb_subkeys_need_update(struct regsubkey_ctr *subkeys)
{
  return (regdb_get_seqnum() != regsubkey_ctr_get_seqnum(subkeys));
}

static bool regdb_values_need_update(struct regval_ctr *values)
{
  return (regdb_get_seqnum() != regval_ctr_get_seqnum(values));
}

/*
 * Table of function pointers for default access
 */

struct registry_ops regdb_ops = {
  .fetch_subkeys = regdb_fetch_keys,
  .fetch_values = regdb_fetch_values,
  .store_subkeys = regdb_store_keys,
  .store_values = regdb_store_values,
  .create_subkey = regdb_create_subkey,
  .delete_subkey = regdb_delete_subkey,
  .get_secdesc = regdb_get_secdesc,
  .set_secdesc = regdb_set_secdesc,
  .subkeys_need_update = regdb_subkeys_need_update,
  .values_need_update = regdb_values_need_update
};

Coverage Report

Created: 2025-11-16 06:57