Reduce limits for various WASM compilation parameters

.gitignore

@@ -1,3 +1,4 @@
 target
 Cargo.lock
 rusty-tags.*
+tags

src/limits.rs

@@ -13,22 +13,22 @@
  * limitations under the License.
  */
 
-// The following limits are imposed by wasmparser on WebAssembly modules.
-// The limits are agreed upon with other engines for consistency.
-pub const MAX_WASM_TYPES: usize = 1_000_000;
-pub const MAX_WASM_FUNCTIONS: usize = 1_000_000;
-pub const _MAX_WASM_IMPORTS: usize = 100_000;
-pub const _MAX_WASM_EXPORTS: usize = 100_000;
-pub const MAX_WASM_GLOBALS: usize = 1_000_000;
-pub const _MAX_WASM_DATA_SEGMENTS: usize = 100_000;
-pub const MAX_WASM_MEMORY_PAGES: usize = 65536;
+// The following limits are updated to fit the restrictions of a WASM smart
+// contract, which should be much lower than for the usual WASM use-case.
+pub const MAX_WASM_TYPES: usize = 10_000;
+pub const MAX_WASM_FUNCTIONS: usize = 10_000;
+pub const _MAX_WASM_IMPORTS: usize = 1000;
+pub const _MAX_WASM_EXPORTS: usize = 1000;
+pub const MAX_WASM_GLOBALS: usize = 4000; // max 32K
+pub const _MAX_WASM_DATA_SEGMENTS: usize = 10_000;
+pub const MAX_WASM_MEMORY_PAGES: usize = 1000; // max 64M memory
 pub const MAX_WASM_STRING_SIZE: usize = 100_000;
-pub const _MAX_WASM_MODULE_SIZE: usize = 1024 * 1024 * 1024; //= 1 GiB
+pub const _MAX_WASM_MODULE_SIZE: usize = 1024 * 1024 * 32; // 32M
 pub const MAX_WASM_FUNCTION_SIZE: usize = 128 * 1024;
-pub const MAX_WASM_FUNCTION_LOCALS: usize = 50000;
-pub const MAX_WASM_FUNCTION_PARAMS: usize = 1000;
-pub const MAX_WASM_FUNCTION_RETURNS: usize = 1000;
-pub const _MAX_WASM_TABLE_SIZE: usize = 10_000_000;
-pub const MAX_WASM_TABLE_ENTRIES: usize = 10_000_000;
+pub const MAX_WASM_FUNCTION_LOCALS: usize = 4000;
+pub const MAX_WASM_FUNCTION_PARAMS: usize = 100;
+pub const MAX_WASM_FUNCTION_RETURNS: usize = 100;
+pub const _MAX_WASM_TABLE_SIZE: usize = 10_000;
+pub const MAX_WASM_TABLE_ENTRIES: usize = 10_000;
 pub const MAX_WASM_TABLES: usize = 1;
 pub const MAX_WASM_MEMORIES: usize = 1;