fix(forge): new error message for vm.addr() when passing invalid priv…

…ate keys (#2164)

* fix(forge): new error message for vm.addr() when passing invalid private keys

* using curve order from the dependency and better error messages

* Apply suggestions from code review

Co-authored-by: Georgios Konstantopoulos <me@gakonst.com>

evm/src/executor/inspector/cheatcodes/util.rs

@@ -3,7 +3,11 @@ use crate::abi::HEVMCalls;
 use bytes::{BufMut, Bytes, BytesMut};
 use ethers::{
     abi::{AbiEncode, Address, Token},
-    prelude::{k256::ecdsa::SigningKey, Lazy, LocalWallet, Signer, H160},
+    core::k256::elliptic_curve::Curve,
+    prelude::{
+        k256::{ecdsa::SigningKey, elliptic_curve::bigint::Encoding, Secp256k1},
+        Lazy, LocalWallet, Signer, H160,
+    },
     types::{NameOrAddress, H256, U256},
     utils,
     utils::keccak256,
@@ -26,6 +30,10 @@ fn addr(private_key: U256) -> Result<Bytes, Bytes> {
         return Err("Private key cannot be 0.".to_string().encode().into())
     }
 
+    if private_key > U256::from_big_endian(&Secp256k1::ORDER.to_be_bytes()) {
+        return Err("Private key must be less than 115792089237316195423570985008687907852837564279074904382605163141518161494337 (the secp256k1 curve order).".to_string().encode().into())
+    }
+
     let mut bytes: [u8; 32] = [0; 32];
     private_key.to_big_endian(&mut bytes);
 
@@ -39,6 +47,10 @@ fn sign(private_key: U256, digest: H256, chain_id: U256) -> Result<Bytes, Bytes>
         return Err("Private key cannot be 0.".to_string().encode().into())
     }
 
+    if private_key > U256::from_big_endian(&Secp256k1::ORDER.to_be_bytes()) {
+        return Err("Private key must be less than 115792089237316195423570985008687907852837564279074904382605163141518161494337 (the secp256k1 curve order).".to_string().encode().into())
+    }
+
     let mut bytes: [u8; 32] = [0; 32];
     private_key.to_big_endian(&mut bytes);
 

forge/README.md

@@ -138,7 +138,8 @@ which implements the following methods:
 
 - `function addr(uint sk) public returns (address addr)` Derives an ethereum
   address from the private key `sk`. Note that `hevm.addr(0)` will fail with
-  `BadCheatCode` as `0` is an invalid ECDSA private key.
+  `BadCheatCode` as `0` is an invalid ECDSA private key. `sk` values above the 
+  secp256k1 curve order, near the max uint256 value will also fail.
 
 - `function ffi(string[] calldata) external returns (bytes memory)` Executes the
   arguments as a command in the system shell and returns stdout. Note that this