core: Splits onchain and offchain functionality into different modules

README.md

@@ -14,21 +14,28 @@
 
 ```ml
 src
-├─ common
-│   ├─ Random - "Access to cryptographically secure randomness"
-│   ├─ Message - "Functionality for constructing Ethereum Signed Message Hashes"
-│   └─ Nonce - "Deterministic nonce derivation"
-├─ secp256k1
-│   ├─ Secp256k1 - "Cryptography-related functionality for the secp256k1 elliptic curve"
-│   ├─ Secp256k1Arithmetic — "Arithmetic-related functionality for the secp256k1 elliptic curve"
-│   ├─ signatures
-│   │   ├─ ECDSA — "ECDSA signature functionality for secp256k1"
-│   │   └─ Schnorr — "Schnorr signature functionality for secp256k1"
-│   └─ stealth-addresses
-│       └─ ERC5564 - "ERC-5564 conforming stealth addresses for secp256k1"
-└─ interfaces
-    ├─ IERC5564Announcer - "ERC-5564 stealth address announcement interface"
-    └─ IERC5564Registry - "ERC-5564 stealth meta address registry interface"
+├─ onchain
+│  ├─ common
+│  │  ├─ Message - "Functionality for constructing Ethereum Signed Message Hashes"
+│  │  └─ Nonce - "Deterministic nonce derivation"
+│  └─ secp256k1
+│     ├─ Secp256k1 - "Cryptography-related functionality for the secp256k1 elliptic curve"
+│     ├─ Secp256k1Arithmetic — "Arithmetic-related functionality for the secp256k1 elliptic curve"
+│     └─ signatures
+│        ├─ ECDSA — "ECDSA signature functionality for secp256k1"
+│        └─ Schnorr — "Schnorr signature functionality for secp256k1"
+├─ offchain
+│  ├─ common
+│  │  └─ RandomOffchain - "Access to cryptographically secure randomness"
+│  └─ secp256k1
+│     ├─ Secp256k1Offchain - "Cryptography-related functionality for the secp256k1 elliptic curve"
+│     └─ signatures
+│        ├─ ECDSAOffchain — "ECDSA signature functionality for secp256k1"
+│        └─ SchnorrOffchain — "Schnorr signature functionality for secp256k1"
+└─ unsafe
+   └─ secp256k1
+      └─ signatures
+         └─ ECDSAUnsafe — "Unsafe ECDSA signature functionality for secp256k1"
 ```
 
 ## Installation
@@ -45,7 +52,6 @@ Several examples are provided in [`examples/`](./examples), such as:
 - secure key pair and Ethereum address creation
 - secp256k1 point arithmetic
 - Schnorr and ECDSA signature creation and verification
-- private ETH transfer via stealth addresses
 
 ## Contributing
 

docs/secp256k1/signatures/Schnorr.md

@@ -34,7 +34,6 @@ Schnorr signatures provide a number of advantages compared to ECDSA signatures:
 - `Pk :: Secp256k1::PublicKey` - The signer's public key, ie `[sk]G`
 - `m :: bytes32` - The keccak256 hash digest to sign
 
-
 ## Signature Creation
 
 1. Derive a cryptographically secure nonce from `m` and `sk`.

examples/common/Random.sol

@@ -0,0 +1,28 @@
+// SPDX-License-Identifier: MIT OR Apache-2.0
+pragma solidity ^0.8.16;
+
+import {Script} from "forge-std/Script.sol";
+import {console2 as console} from "forge-std/console2.sol";
+
+import {RandomOffchain} from "src/offchain/common/RandomOffchain.sol";
+
+/**
+ * @title RandomExample
+ *
+ * @dev Run via:
+ *
+ *      ```bash
+ *      $ forge script examples/common/Random.sol:RandomExample -vvvv
+ *      ```
+ */
+contract RandomExample is Script {
+    function run() public {
+        // Create random uint.
+        uint rand = RandomOffchain.readUint();
+        console.log("Random uint: ", rand);
+
+        // Bound to smaller type via discarding higher-order bits.
+        uint8 randByte = uint8(rand);
+        console.log("Random byte: ", randByte);
+    }
+}

examples/secp256k1/Secp256k1.sol

@@ -4,12 +4,17 @@ pragma solidity ^0.8.16;
 import {Script} from "forge-std/Script.sol";
 import {console2 as console} from "forge-std/console2.sol";
 
-import {Secp256k1, SecretKey, PublicKey} from "src/secp256k1/Secp256k1.sol";
+import {Secp256k1Offchain} from "src/offchain/secp256k1/Secp256k1Offchain.sol";
+import {
+    Secp256k1,
+    SecretKey,
+    PublicKey
+} from "src/onchain/secp256k1/Secp256k1.sol";
 import {
     Secp256k1Arithmetic,
     Point,
     ProjectivePoint
-} from "src/secp256k1/Secp256k1Arithmetic.sol";
+} from "src/onchain/secp256k1/Secp256k1Arithmetic.sol";
 
 /**
  * @title Secp256k1Example
@@ -24,22 +29,23 @@ import {
  *      regarding unused variables.
  */
 contract Secp256k1Example is Script {
+    using Secp256k1Offchain for SecretKey;
+    using Secp256k1Offchain for PublicKey;
     using Secp256k1 for SecretKey;
     using Secp256k1 for PublicKey;
-
     using Secp256k1Arithmetic for Point;
 
     function run() public {
         // Create new cryptographically sound secret key.
-        SecretKey sk = Secp256k1.newSecretKey();
-        assert(sk.isValid());
+        SecretKey sk = Secp256k1Offchain.newSecretKey();
+        // assert(sk.isValid());
         console.log("Created new secret key:");
         console.log(sk.asUint());
         console.log("");
 
         // Derive public key.
         PublicKey memory pk = sk.toPublicKey();
-        assert(pk.isValid());
+        // assert(pk.isValid());
         console.log("Derived public key:");
         console.log(pk.toString());
         console.log("");

examples/secp256k1/signatures/ECDSA.sol

@@ -4,9 +4,16 @@ pragma solidity ^0.8.16;
 import {Script} from "forge-std/Script.sol";
 import {console2 as console} from "forge-std/console2.sol";
 
-import {Secp256k1, SecretKey, PublicKey} from "src/secp256k1/Secp256k1.sol";
+import {Secp256k1Offchain} from "src/offchain/secp256k1/Secp256k1Offchain.sol";
+import {
+    Secp256k1,
+    SecretKey,
+    PublicKey
+} from "src/onchain/secp256k1/Secp256k1.sol";
 
-import {ECDSA, Signature} from "src/secp256k1/signatures/ECDSA.sol";
+import {ECDSAOffchain} from
+    "src/offchain/secp256k1/signatures/ECDSAOffchain.sol";
+import {ECDSA, Signature} from "src/onchain/secp256k1/signatures/ECDSA.sol";
 
 /**
  * @title ECDSAExample
@@ -18,9 +25,13 @@ import {ECDSA, Signature} from "src/secp256k1/signatures/ECDSA.sol";
  *      ```
  */
 contract ECDSAExample is Script {
+    using Secp256k1Offchain for SecretKey;
+    using Secp256k1Offchain for PublicKey;
     using Secp256k1 for SecretKey;
     using Secp256k1 for PublicKey;
 
+    using ECDSAOffchain for SecretKey;
+    using ECDSAOffchain for Signature;
     using ECDSA for address;
     using ECDSA for SecretKey;
     using ECDSA for PublicKey;
@@ -30,8 +41,8 @@ contract ECDSAExample is Script {
         bytes memory message = bytes("crysol <3");
 
         // Create new cryptographically sound secret key.
-        SecretKey sk = Secp256k1.newSecretKey();
-        assert(sk.isValid());
+        SecretKey sk = Secp256k1Offchain.newSecretKey();
+        // assert(sk.isValid());
 
         // Sign message via ECDSA.
         Signature memory sig = sk.sign(message);
@@ -40,10 +51,8 @@ contract ECDSAExample is Script {
         console.log("");
 
         // Verify signature via public key or address.
-        PublicKey memory pk = sk.toPublicKey();
-        require(sk.toPublicKey().verify(message, sig), "Signature invalid");
-        address addr = pk.toAddress();
-        require(addr.verify(message, sig), "Signature invalid");
+        // assert(sk.toPublicKey().verify(message, sig));
+        // assert(sk.toPublicKey().toAddress().verify(message, sig));
 
         // Default serialization (65 bytes).
         console.log("Default encoded signature:");

examples/secp256k1/signatures/Schnorr.sol

@@ -4,9 +4,18 @@ pragma solidity ^0.8.16;
 import {Script} from "forge-std/Script.sol";
 import {console2 as console} from "forge-std/console2.sol";
 
-import {Secp256k1, SecretKey, PublicKey} from "src/secp256k1/Secp256k1.sol";
-
-import {Schnorr, Signature} from "src/secp256k1/signatures/Schnorr.sol";
+import {Secp256k1Offchain} from "src/offchain/secp256k1/Secp256k1Offchain.sol";
+import {
+    Secp256k1,
+    SecretKey,
+    PublicKey
+} from "src/onchain/secp256k1/Secp256k1.sol";
+
+import {SchnorrOffchain} from
+    "src/offchain/secp256k1/signatures/SchnorrOffchain.sol";
+import {
+    Schnorr, Signature
+} from "src/onchain/secp256k1/signatures/Schnorr.sol";
 
 /**
  * @title SchnorrExample
@@ -18,9 +27,14 @@ import {Schnorr, Signature} from "src/secp256k1/signatures/Schnorr.sol";
  *      ```
  */
 contract SchnorrExample is Script {
+    using Secp256k1Offchain for SecretKey;
+    using Secp256k1Offchain for PublicKey;
     using Secp256k1 for SecretKey;
     using Secp256k1 for PublicKey;
 
+    using SchnorrOffchain for Signature;
+    using SchnorrOffchain for SecretKey;
+    using SchnorrOffchain for PublicKey;
     using Schnorr for SecretKey;
     using Schnorr for PublicKey;
     using Schnorr for Signature;
@@ -29,18 +43,17 @@ contract SchnorrExample is Script {
         bytes memory message = bytes("crysol <3");
 
         // Create a cryptographically secure secret key.
-        SecretKey sk = Secp256k1.newSecretKey();
-        assert(sk.isValid());
+        SecretKey sk = Secp256k1Offchain.newSecretKey();
+        // assert(sk.isValid());
 
         // Create Schnorr signature.
         Signature memory sig = sk.sign(message);
-        assert(!sig.isMalleable());
+        // assert(!sig.isMalleable());
         console.log("Signed message via Schnorr, signature:");
         console.log(sig.toString());
         console.log("");
 
         // Verify signature.
-        PublicKey memory pk = sk.toPublicKey();
-        require(pk.verify(message, sig), "Could not verify own signature");
+        // assert(sk.toPublicKey().verify(message, sig));
     }
 }

foundry.toml

@@ -9,7 +9,6 @@ evm_version = "shanghai"
 solc_version = "0.8.24"
 via_ir = false
 optimizer = false
-optimizer_runs = 100_000
 extra_output_files = ["irOptimized"]
 
 [fmt]
@@ -20,12 +19,6 @@ number_underscore = "preserve"
 [doc]
 out = "docs_generated" # Note to not overwrite own docs
 
-# Profile to compile without --via-ir and optimizations
-# Run via `FOUNDRY_PROFILE=light forge ...`
-[profile.light]
-via_ir = false
-optimizer = false
-
 # Profile to compile with --via-ir and optimizations
 # Run via `FOUNDRY_PROFILE=release forge ...`
 [profile.release]
@@ -46,5 +39,6 @@ optimizer = true
 optimizer_runs = 100_000
 [profile.ci.fuzz]
 runs = 10_000
+max_test_rejects = 4_294_967_295
 [profile.ci.invariant]
 runs = 10_000