adjustments

Signed-off-by: Ignacio Hagopian <jsign.uy@gmail.com>

Author: jsign

tests/zkevm/test_worst_compute.py

@@ -115,33 +115,25 @@ def test_worst_keccak(
         36_000_000,
     ],
 )
-@pytest.mark.parametrize(
-    "base_mod_length, exp_length",
-    [
-        (32, 32),
-    ],
-)
 def test_worst_modexp(
     blockchain_test: BlockchainTestFiller,
     pre: Alloc,
     fork: Fork,
     gas_limit: int,
-    base_mod_length: int,
-    exp_length: int,
+    
 ):
     """Test running a block with as many MODEXP calls as possible."""
     env = Environment(gas_limit=gas_limit)
 
+    base_mod_length = 32
+    exp_length = 32
+
     base = 2 ** (8 * base_mod_length) - 1
-    mod = 2 ** (8 * base_mod_length) - 1
+    mod = 2 ** (8 * base_mod_length) - 2 # Prevnts base == mod
     exp = 2 ** (8 * exp_length) - 1
 
-    # EIP-7883 (TODO: generalize)
-    mul_complexity = math.ceil(base_mod_length / 8) ** 2
-    iter_complexity = exp.bit_length() - 1
-    gas_cost = math.floor((mul_complexity * iter_complexity) / 3)
-
-    mem_prep = (
+    # MODEXP calldata
+    calldata = (
         Op.MSTORE(0 * 32, 32)
         + Op.MSTORE(1 * 32, 32)
         + Op.MSTORE(2 * 32, 32)
@@ -150,14 +142,19 @@ def test_worst_modexp(
         + Op.MSTORE(5 * 32, mod)
     )
 
+    # EIP-2565
+    mul_complexity = math.ceil(base_mod_length / 8) ** 2
+    iter_complexity = exp.bit_length() - 1
+    gas_cost = math.floor((mul_complexity * iter_complexity) / 3)
     attack_block = Op.STATICCALL(gas_cost, 0x5, 0, 32 * 6, 0, 0) + Op.POP
 
+    # The attack contract is: JUMPDEST + [attack_block]* + PUSH0 + JUMP
     jumpdest = Op.JUMPDEST
-    jump_back = Op.JUMP(len(mem_prep))
-    max_iters_loop = (MAX_CODE_SIZE - len(mem_prep) - len(jumpdest) - len(jump_back)) // len(
+    jump_back = Op.JUMP(len(calldata))
+    max_iters_loop = (MAX_CODE_SIZE - len(calldata) - len(jumpdest) - len(jump_back)) // len(
         attack_block
     )
-    code = mem_prep + jumpdest + sum([attack_block] * max_iters_loop) + jump_back
+    code = calldata + jumpdest + sum([attack_block] * max_iters_loop) + jump_back
     if len(code) > MAX_CODE_SIZE:
         # Must never happen, but keep it as a sanity check.
         raise ValueError(f"Code size {len(code)} exceeds maximum code size {MAX_CODE_SIZE}")