s3:registry: add an extra check for dsize==0 to regdb_fetch_keys_internal()
[ira/wip.git] / source3 / registry / reg_backend_db.c
index e0e234f7c6880d59ebcfa0a4c400c8d7315ff067..43963db3c29a26d451b73141f56f73157fd655b6 100644 (file)
@@ -2,6 +2,7 @@
  *  Unix SMB/CIFS implementation.
  *  Virtual Windows Registry Layer
  *  Copyright (C) Gerald Carter                     2002-2005
+ *  Copyright (C) Michael Adam                      2007-2009
  *
  *  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
@@ -29,8 +30,8 @@ static int regdb_refcount;
 
 static bool regdb_key_exists(struct db_context *db, const char *key);
 static bool regdb_key_is_base_key(const char *key);
-static int regdb_fetch_keys_internal(struct db_context *db, const char *key,
-                                    struct regsubkey_ctr *ctr);
+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,
@@ -182,7 +183,13 @@ static WERROR init_registry_key_internal(struct db_context *db,
                        goto fail;
                }
 
-               regdb_fetch_keys_internal(db, base, subkeys);
+               werr = regdb_fetch_keys_internal(db, base, subkeys);
+               if (!W_ERROR_IS_OK(werr) &&
+                   !W_ERROR_EQUAL(werr, WERR_NOT_FOUND))
+               {
+                       goto fail;
+               }
+
                if (*subkeyname) {
                        werr = regsubkey_ctr_addkey(subkeys, subkeyname);
                        if (!W_ERROR_IS_OK(werr)) {
@@ -243,8 +250,6 @@ WERROR init_registry_key(const char *add_path)
 static void regdb_ctr_add_value(struct regval_ctr *ctr,
                                struct builtin_regkey_value *value)
 {
-       UNISTR2 data;
-
        switch(value->type) {
        case REG_DWORD:
                regval_ctr_addvalue(ctr, value->valuename, REG_DWORD,
@@ -253,10 +258,8 @@ static void regdb_ctr_add_value(struct regval_ctr *ctr,
                break;
 
        case REG_SZ:
-               init_unistr2(&data, value->data.string, UNI_STR_TERMINATE);
-               regval_ctr_addvalue(ctr, value->valuename, REG_SZ,
-                                   (char*)data.buffer,
-                                   data.uni_str_len*sizeof(uint16));
+               regval_ctr_addvalue_sz(ctr, value->valuename,
+                                      value->data.string);
                break;
 
        default:
@@ -750,7 +753,12 @@ static NTSTATUS regdb_store_keys_action(struct db_context *db,
        werr = regsubkey_ctr_init(mem_ctx, &old_subkeys);
        W_ERROR_NOT_OK_GOTO_DONE(werr);
 
-       regdb_fetch_keys_internal(db, store_ctx->key, old_subkeys);
+       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:
@@ -839,7 +847,8 @@ static NTSTATUS regdb_store_keys_action(struct db_context *db,
                werr = regsubkey_ctr_init(mem_ctx, &subkeys);
                W_ERROR_NOT_OK_GOTO_DONE(werr);
 
-               if (regdb_fetch_keys_internal(db, path, subkeys) == -1) {
+               werr = regdb_fetch_keys_internal(db, path, subkeys);
+               if (!W_ERROR_IS_OK(werr)) {
                        /* create a record with 0 subkeys */
                        werr = regdb_store_keys_internal2(db, path, subkeys);
                        if (!W_ERROR_IS_OK(werr)) {
@@ -886,7 +895,12 @@ static bool regdb_store_keys_internal(struct db_context *db, const char *key,
                goto done;
        }
 
-       regdb_fetch_keys_internal(db, key, old_subkeys);
+       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);
@@ -956,10 +970,8 @@ static NTSTATUS regdb_create_subkey_action(struct db_context *db,
        werr = regsubkey_ctr_init(mem_ctx, &subkeys);
        W_ERROR_NOT_OK_GOTO_DONE(werr);
 
-       if (regdb_fetch_keys_internal(db, create_ctx->key, subkeys) < 0) {
-               werr = WERR_REG_IO_FAILURE;
-               goto done;
-       }
+       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);
@@ -991,10 +1003,8 @@ static WERROR regdb_create_subkey(const char *key, const char *subkey)
        werr = regsubkey_ctr_init(mem_ctx, &subkeys);
        W_ERROR_NOT_OK_GOTO_DONE(werr);
 
-       if (regdb_fetch_keys_internal(regdb, key, subkeys) < 0) {
-               werr = WERR_REG_IO_FAILURE;
-               goto done;
-       }
+       werr = regdb_fetch_keys_internal(regdb, key, subkeys);
+       W_ERROR_NOT_OK_GOTO_DONE(werr);
 
        if (regsubkey_ctr_key_exists(subkeys, subkey)) {
                werr = WERR_OK;
@@ -1041,10 +1051,8 @@ static NTSTATUS regdb_delete_subkey_action(struct db_context *db,
        werr = regsubkey_ctr_init(mem_ctx, &subkeys);
        W_ERROR_NOT_OK_GOTO_DONE(werr);
 
-       if (regdb_fetch_keys_internal(db, delete_ctx->key, subkeys) < 0) {
-               werr = WERR_REG_IO_FAILURE;
-               goto done;
-       }
+       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);
@@ -1174,39 +1182,58 @@ static int cmp_keynames(const void *p1, const void *p2)
        return StrCaseCmp(*((char **)p1), *((char **)p2));
 }
 
-static bool create_sorted_subkeys(const char *key, const char *sorted_keyname)
+struct create_sorted_subkeys_context {
+       const char *key;
+       const char *sorted_keyname;
+};
+
+static NTSTATUS create_sorted_subkeys_action(struct db_context *db,
+                                            void *private_data)
 {
        char **sorted_subkeys;
        struct regsubkey_ctr *ctr;
-       bool result = false;
        NTSTATUS status;
        char *buf;
        char *p;
-       int i, res;
+       int i;
        size_t len;
        int num_subkeys;
-       WERROR werr;
+       struct create_sorted_subkeys_context *sorted_ctx;
 
-       if (regdb->transaction_start(regdb) != 0) {
-               DEBUG(0, ("create_sorted_subkeys: transaction_start "
-                         "failed\n"));
-               return false;
-       }
+       sorted_ctx = (struct create_sorted_subkeys_context *)private_data;
 
-       werr = regsubkey_ctr_init(talloc_tos(), &ctr);
-       if (!W_ERROR_IS_OK(werr)) {
-               goto commit;
+       /*
+        * In this function, we only treat failing of the actual write to
+        * the db as a real error. All preliminary errors, at a stage when
+        * nothing has been written to the DB yet are treated as success
+        * to be committed (as an empty transaction).
+        *
+        * The reason is that this (disposable) call might be nested in other
+        * transactions. Doing a cancel here would destroy the possibility of
+        * a transaction_commit for transactions that we might be wrapped in.
+        */
+
+       status = werror_to_ntstatus(regsubkey_ctr_init(talloc_tos(), &ctr));
+       if (!NT_STATUS_IS_OK(status)) {
+               /* don't treat this as an error */
+               status = NT_STATUS_OK;
+               goto done;
        }
 
-       res = regdb_fetch_keys_internal(regdb, key, ctr);
-       if (res == -1) {
-               goto commit;
+       status = werror_to_ntstatus(regdb_fetch_keys_internal(db,
+                                                             sorted_ctx->key,
+                                                             ctr));
+       if (!NT_STATUS_IS_OK(status)) {
+               /* don't treat this as an error */
+               status = NT_STATUS_OK;
+               goto done;
        }
 
        num_subkeys = regsubkey_ctr_numkeys(ctr);
        sorted_subkeys = talloc_array(ctr, char *, num_subkeys);
        if (sorted_subkeys == NULL) {
-               goto commit;
+               /* don't treat this as an error */
+               goto done;
        }
 
        len = 4 + 4*num_subkeys;
@@ -1215,7 +1242,8 @@ static bool create_sorted_subkeys(const char *key, const char *sorted_keyname)
                sorted_subkeys[i] = talloc_strdup_upper(sorted_subkeys,
                                        regsubkey_ctr_specific_key(ctr, i));
                if (sorted_subkeys[i] == NULL) {
-                       goto commit;
+                       /* don't treat this as an error */
+                       goto done;
                }
                len += strlen(sorted_subkeys[i])+1;
        }
@@ -1224,7 +1252,8 @@ static bool create_sorted_subkeys(const char *key, const char *sorted_keyname)
 
        buf = talloc_array(ctr, char, len);
        if (buf == NULL) {
-               goto commit;
+               /* don't treat this as an error */
+               goto done;
        }
        p = buf + 4 + 4*num_subkeys;
 
@@ -1238,43 +1267,28 @@ static bool create_sorted_subkeys(const char *key, const char *sorted_keyname)
        }
 
        status = dbwrap_store_bystring(
-               regdb, sorted_keyname, make_tdb_data((uint8_t *)buf, len),
+               db, sorted_ctx->sorted_keyname, make_tdb_data((uint8_t *)buf,
+               len),
                TDB_REPLACE);
-       if (!NT_STATUS_IS_OK(status)) {
-               /*
-                * Don't use a "goto commit;" here, this would commit the broken
-                * transaction. See below for an explanation.
-                */
-               goto cancel;
-       }
 
-       result = true;
+done:
+       talloc_free(ctr);
+       return status;
+}
 
-commit:
-       /*
-        * We only get here via the "goto commit" when we did not write anything
-        * yet. Using transaction_commit even in a failure case is necessary
-        * because this (disposable) call might be nested in other
-        * transactions. Doing a cancel here would destroy the possibility of
-        * a transaction_commit for transactions that we might be wrapped in.
-        */
-       if (regdb->transaction_commit(regdb) == -1) {
-               DEBUG(0, ("create_sorted_subkeys: transaction_commit "
-                         "failed\n"));
-               result = false;
-       }
-       goto done;
+static bool create_sorted_subkeys(const char *key, const char *sorted_keyname)
+{
+       NTSTATUS status;
+       struct create_sorted_subkeys_context sorted_ctx;
 
-cancel:
-       if (regdb->transaction_cancel(regdb) == -1) {
-               smb_panic("create_sorted_subkeys: transaction_cancel "
-                         "failed\n");
-       }
-       result = false;
+       sorted_ctx.key = key;
+       sorted_ctx.sorted_keyname = sorted_keyname;
 
-done:
-       TALLOC_FREE(ctr);
-       return result;
+       status = dbwrap_trans_do(regdb,
+                                create_sorted_subkeys_action,
+                                &sorted_ctx);
+
+       return NT_STATUS_IS_OK(status);
 }
 
 struct scan_subkey_state {
@@ -1420,42 +1434,49 @@ done:
  released by the caller.
  ***********************************************************************/
 
-static int regdb_fetch_keys_internal(struct db_context *db, const char *key,
-                                    struct regsubkey_ctr *ctr)
+static WERROR regdb_fetch_keys_internal(struct db_context *db, const char *key,
+                                       struct regsubkey_ctr *ctr)
 {
        WERROR werr;
-       uint32 num_items;
+       uint32_t num_items;
        uint8 *buf;
        uint32 buflen, len;
        int i;
        fstring subkeyname;
-       int ret = -1;
        TALLOC_CTX *frame = talloc_stackframe();
        TDB_DATA value;
 
        DEBUG(11,("regdb_fetch_keys: Enter key => [%s]\n", key ? key : "NULL"));
 
+       frame = talloc_stackframe();
+
        if (!regdb_key_exists(db, key)) {
+               DEBUG(10, ("key [%s] not found\n", key));
+               werr = WERR_NOT_FOUND;
                goto done;
        }
 
        werr = regsubkey_ctr_set_seqnum(ctr, db->get_seqnum(db));
-       if (!W_ERROR_IS_OK(werr)) {
-               goto done;
-       }
+       W_ERROR_NOT_OK_GOTO_DONE(werr);
 
        value = regdb_fetch_key_internal(db, frame, key);
 
-       if (value.dptr == NULL) {
+       if (value.dsize == 0 || value.dptr == NULL) {
                DEBUG(10, ("regdb_fetch_keys: no subkeys found for key [%s]\n",
                           key));
-               ret = 0;
                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;
+       }
+
+       werr = regsubkey_ctr_reinit(ctr);
+       W_ERROR_NOT_OK_GOTO_DONE(werr);
 
        for (i=0; i<num_items; i++) {
                len += tdb_unpack(buf+len, buflen-len, "f", subkeyname);
@@ -1463,21 +1484,28 @@ static int regdb_fetch_keys_internal(struct db_context *db, const char *key,
                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));
 
-       ret = num_items;
 done:
        TALLOC_FREE(frame);
-       return ret;
+       return werr;
 }
 
 int regdb_fetch_keys(const char *key, struct regsubkey_ctr *ctr)
 {
-       return regdb_fetch_keys_internal(regdb, key, ctr);
+       WERROR werr;
+
+       werr = regdb_fetch_keys_internal(regdb, key, ctr);
+       if (!W_ERROR_IS_OK(werr)) {
+               return -1;
+       }
+
+       return regsubkey_ctr_numkeys(ctr);
 }
 
 /****************************************************************************