Fix incorrect WASM memory offset

reserved_offset was two bytes off, this was causing adjustWebGL to replace two bytes of the xoring array in memory, which changed the farbling outcome on subsequent WebGL farbling runs.
polcak · Jul 4, 2023 · 141ee1d · 141ee1d
1 parent 10ae9ae
commit 141ee1d
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Showing 2 changed files with 4 additions and 4 deletions.
diff --git a/common/code_builders.js b/common/code_builders.js
@@ -371,10 +371,10 @@ function insert_wasm_code(code) {
 		// | CRC table       | Xoring table | Reserved | Data
 		// | 256 * u16       | 8 * u32      |          | 
 		// +-----------------+--------------+----------+---------------------------------------- - -
-		// 0                 512            542        1024
+		// 0                 512            544        1024
 		const crc_offset = 0;
 		const xoring_offset = 512;
-		const reserved_offset = 542;
+		const reserved_offset = 544;
 		const data_offset = 1024;
 
 		WebAssembly.instantiateStreaming(fetch("/* WASM_URL */"), {env: {memory: wasm_memory}}).then(result => {

diff --git a/wasm/assembly/farble.ts b/wasm/assembly/farble.ts
@@ -24,10 +24,10 @@
 // | CRC table       | Xoring table | Reserved | Data
 // | 256 * u16       | 8 * u32      |          | 
 // +-----------------+--------------+----------+---------------------------------------- - -
-// 0                 512            542        1024
+// 0                 512            544        1024
 const crc_offset: usize = 0;
 const xoring_offset: usize = 512;
-const reserved_offset: usize = 542;
+const reserved_offset: usize = 544;
 const data_offset: usize = 1024;
 
 var seed: u64;