db: add security pragmas and STRICT tables for developer mode

Enable trusted_schema=OFF and cell_size_check=ON pragmas when
running in developer mode for enhanced security and debugging.

Add STRICT keyword to CREATE TABLE statements in developer mode
for improved type safety with SQLite 3.37.0+.

Add missing VARCHAR and INT type conversions in sql-rewrite.py.

Addresses feedback from issue #7913.

Author: wqxoxo

db/db_sqlite3.c

@@ -205,16 +205,44 @@ static bool db_sqlite3_setup(struct db *db, bool create)
 			   "PRAGMA foreign_keys = ON;", -1, &stmt, NULL);
 	err = sqlite3_step(stmt);
 	sqlite3_finalize(stmt);
-	return err == SQLITE_DONE;
+
+	if (err != SQLITE_DONE)
+		return false;
+
+	if (db->developer) {
+		sqlite3_prepare_v2(conn2sql(db->conn),
+				   "PRAGMA trusted_schema = OFF;", -1, &stmt, NULL);
+		sqlite3_step(stmt);
+		sqlite3_finalize(stmt);
+
+		sqlite3_prepare_v2(conn2sql(db->conn),
+				   "PRAGMA cell_size_check = ON;", -1, &stmt, NULL);
+		sqlite3_step(stmt);
+		sqlite3_finalize(stmt);
+	}
+
+	return true;
 }
 
 static bool db_sqlite3_query(struct db_stmt *stmt)
 {
 	sqlite3_stmt *s;
 	sqlite3 *conn = conn2sql(stmt->db->conn);
 	int err;
+	const char *query = stmt->query->query;
+	char *modified_query = NULL;
+
+	if (stmt->db->developer &&
+	    strncasecmp(query, "CREATE TABLE", 12) == 0 &&
+	    !strstr(query, "STRICT")) {
+		modified_query = tal_fmt(stmt, "%s STRICT", query);
+		query = modified_query;
+	}
+
+	err = sqlite3_prepare_v2(conn, query, -1, &s, NULL);
 
-	err = sqlite3_prepare_v2(conn, stmt->query->query, -1, &s, NULL);
+	if (modified_query)
+		tal_free(modified_query);
 
 	for (size_t i=0; i<stmt->query->placeholders; i++) {
 		struct db_binding *b = &stmt->bindings[i];

devtools/sql-rewrite.py

@@ -45,6 +45,8 @@ def rewrite_single(self, query):
             r'BIGINT': 'INTEGER',
             r'BIGINTEGER': 'INTEGER',
             r'BIGSERIAL': 'INTEGER',
+            r'VARCHAR(?:\(\d+\))?': 'TEXT',
+            r'\bINT\b': 'INTEGER',
             r'CURRENT_TIMESTAMP\(\)': "strftime('%s', 'now')",
             r'INSERT INTO[ \t]+(.*)[ \t]+ON CONFLICT.*DO NOTHING;': 'INSERT OR IGNORE INTO \\1;',
             # Rewrite "decode('abcd', 'hex')" to become "x'abcd'"

tests/test_db.py

@@ -642,3 +642,22 @@ def test_channel_htlcs_id_change(bitcoind, node_factory):
     # Make some HTLCS
     for amt in (100, 500, 1000, 5000, 10000, 50000, 100000):
         l1.pay(l3, amt)
+
+
+@unittest.skipIf(os.getenv('TEST_DB_PROVIDER', 'sqlite3') != 'sqlite3', "STRICT tables are SQLite3 specific")
+def test_sqlite_strict_mode(node_factory):
+    """Test that STRICT is appended to CREATE TABLE in developer mode."""
+    l1 = node_factory.get_node(options={'developer': None})
+
+    # Query sqlite_master to check table definitions
+    tables = l1.db_query("SELECT name, sql FROM sqlite_master WHERE type='table' AND name NOT LIKE 'sqlite_%'")
+
+    strict_tables = [t for t in tables if t['sql'] and 'STRICT' in t['sql']]
+    assert len(strict_tables) > 0, f"Expected at least one STRICT table in developer mode, found none out of {len(tables)}"
+
+    # Check specific tables we know should be STRICT in developer mode
+    known_strict_tables = ['version', 'forwards', 'payments', 'local_anchors', 'addresses']
+    for table_name in known_strict_tables:
+        table_sql = next((t['sql'] for t in tables if t['name'] == table_name), None)
+        if table_sql:
+            assert 'STRICT' in table_sql, f"Expected table '{table_name}' to be STRICT in developer mode"