add support for prevrando (solc 0.8.18)

CONTRIBUTING.md

@@ -106,7 +106,7 @@ For each new detector, at least one regression tests must be present.
 > - To run tests for a specific test case, run `pytest tests/e2e/solc_parsing/test_ast_parsing.py -k user_defined_value_type`  (the filename is the argument).
 > - To run tests for a specific version, run `pytest tests/e2e/solc_parsing/test_ast_parsing.py -k 0.8.12`.
 > - To run tests for a specific compiler json format, run `pytest tests/e2e/solc_parsing/test_ast_parsing.py -k legacy` (can be legacy or compact).
-> - The IDs of tests can be inspected using ``pytest tests/e2e/solc_parsing/test_ast_parsing.py --collect-only`.
+> - The IDs of tests can be inspected using `pytest tests/e2e/solc_parsing/test_ast_parsing.py --collect-only`.
 
 ### Synchronization with crytic-compile
 

slither/core/declarations/solidity_variables.py

@@ -21,10 +21,11 @@ SOLIDITY_VARIABLES_COMPOSED = {
     "block.basefee": "uint",
     "block.coinbase": "address",
     "block.difficulty": "uint256",
+    "block.prevrandao": "uint256",
     "block.gaslimit": "uint256",
     "block.number": "uint256",
     "block.timestamp": "uint256",
-    "block.blockhash": "uint256",  # alias for blockhash. It's a call
+    "block.blockhash": "bytes32",  # alias for blockhash. It's a call
     "block.chainid": "uint256",
     "msg.data": "bytes",
     "msg.gas": "uint256",
@@ -60,6 +61,7 @@ SOLIDITY_FUNCTIONS: Dict[str, List[str]] = {
     "log2(bytes32,bytes32,bytes32)": [],
     "log3(bytes32,bytes32,bytes32,bytes32)": [],
     "blockhash(uint256)": ["bytes32"],
+    "prevrandao()": ["uint256"],
     # the following need a special handling
     # as they are recognized as a SolidityVariableComposed
     # and converted to a SolidityFunction by SlithIR

slither/solc_parsing/yul/evm_functions.py

@@ -51,6 +51,7 @@ evm_opcodes = [
     "TIMESTAMP",
     "NUMBER",
     "DIFFICULTY",
+    "PREVRANDAO",
     "GASLIMIT",
     "CHAINID",
     "SELFBALANCE",
@@ -168,6 +169,7 @@ builtins = [
     )
 ] + yul_funcs
 
+# "identifier": [input_count, output_count]
 function_args = {
     "byte": [2, 1],
     "addmod": [3, 1],
@@ -221,6 +223,7 @@ function_args = {
     "timestamp": [0, 1],
     "number": [0, 1],
     "difficulty": [0, 1],
+    "prevrandao": [0, 1],
     "gaslimit": [0, 1],
 }
 

tests/e2e/solc_parsing/test_ast_parsing.py

@@ -308,6 +308,7 @@ ALL_TESTS = [
     Test("units_and_global_variables-0.8.0.sol", VERSIONS_08),
     Test("units_and_global_variables-0.8.4.sol", make_version(8, 4, 6)),
     Test("units_and_global_variables-0.8.7.sol", make_version(8, 7, 9)),
+    Test("global_variables-0.8.18.sol", make_version(8, 18, 18)),
     Test(
         "push-all.sol",
         ALL_VERSIONS,

tests/e2e/solc_parsing/test_data/expected/global_variables-0.8.18.sol-0.8.18-compact.json

@@ -0,0 +1,6 @@
+{
+  "C": {
+    "f()": "digraph{\n0[label=\"Node Type: ENTRY_POINT 0\n\"];\n0->1;\n1[label=\"Node Type: RETURN 1\n\"];\n}\n",
+    "g()": "digraph{\n0[label=\"Node Type: ENTRY_POINT 0\n\"];\n0->1;\n1[label=\"Node Type: INLINE ASM 1\n\"];\n1->2;\n2[label=\"Node Type: EXPRESSION 2\n\"];\n}\n"
+  }
+}

tests/e2e/solc_parsing/test_data/global_variables-0.8.18.sol

@@ -0,0 +1,11 @@
+contract C {
+    function f() public view returns (uint256) {
+        return block.prevrandao;
+    }
+
+    function g() public view returns (uint256 ret) {
+        assembly {
+            ret := prevrandao()
+        }
+    }
+}