Initial ChronoSeal release

wasm/src/vm.rs

@@ -0,0 +1,55 @@
+use wasm_bindgen::prelude::*;
+use shared::protocol::StackState;
+
+#[wasm_bindgen]
+pub fn run_program(program_b64: &str) -> JsValue {
+    use base64::Engine;
+    let bytes = base64::engine::general_purpose::STANDARD.decode(program_b64).unwrap();
+    let state = execute(&bytes);
+    serde_wasm_bindgen::to_value(&state).unwrap()
+}
+
+fn execute(program: &[u8]) -> StackState {
+    let mut stack: Vec<u32> = Vec::new();
+    let mut ip: usize = 0;
+    while ip < program.len() {
+        let op = program[ip];
+        ip += 1;
+        match op {
+            0x00 => {
+                if ip + 4 > program.len() { break; }
+                let val = u32::from_le_bytes([program[ip], program[ip+1], program[ip+2], program[ip+3]]);
+                ip += 4;
+                stack.push(val);
+            }
+            0x01..=0x07 => {
+                if stack.len() < 2 { break; }
+                let b = stack.pop().unwrap();
+                let a = stack.pop().unwrap();
+                let r = match op {
+                    0x01 => a.wrapping_add(b),
+                    0x02 => a.wrapping_sub(b),
+                    0x03 => a.wrapping_mul(b),
+                    0x04 => a ^ b,
+                    0x05 => a & b,
+                    0x06 => a | b,
+                    0x07 => a.rotate_left(b % 32),
+                    _ => unreachable!(),
+                };
+                stack.push(r);
+            }
+            0x08 => {
+                if stack.is_empty() { break; }
+                let a = stack.pop().unwrap();
+                stack.push(!a);
+            }
+            0x09 => {
+                let r = shared::hashing::hash_stack(&stack);
+                stack.clear();
+                stack.push(r);
+            }
+            _ => break,
+        }
+    }
+    StackState { stack, ip: ip as u16 }
+}