Move SCL Linked Lib to Embedded

src/libraries/P256SCLVerifierLib.sol

@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: MIT AND Apache-2.0
 pragma solidity 0.8.23;
 
-import { SCL_RIP7212 } from "@SCL/lib/libSCL_RIP7212.sol";
+import { SCL_RIP7212 } from "./libSCL_RIP7212.sol";
 import { ec_isOnCurve } from "@SCL/elliptic/SCL_ecOncurve.sol";
 import { a, b, p, n } from "@SCL/fields/SCL_secp256r1.sol";
 

src/libraries/libSCL_RIP7212.sol

@@ -0,0 +1,52 @@
+/**
+ *
+ */
+/*
+/*   ╔═╗╔╦╗╔═╗╔═╗╔╦╗╦ ╦  ╔═╗╦═╗╦ ╦╔═╗╔╦╗╔═╗╦  ╦╔╗ 
+/*   ╚═╗║║║║ ║║ ║ ║ ╠═╣  ║  ╠╦╝╚╦╝╠═╝ ║ ║ ║║  ║╠╩╗
+/*   ╚═╝╩ ╩╚═╝╚═╝o╩ ╩ ╩  ╚═╝╩╚═ ╩ ╩   ╩ ╚═╝╩═╝╩╚═╝
+/*              
+/* Copyright (C) 2024 - Renaud Dubois - This file is part of SCL (Smoo.th CryptoLib) project
+/* License: This software is licensed under MIT License (and allways will)      
+/* Description: This file implements the ecdsa verification protocol using Shamir's trick + 4bit windowing.                                        
+/********************************************************************************************/
+// SPDX-License-Identifier: MIT
+pragma solidity >=0.8.19 <0.9.0;
+
+import { a, b, p, gx, gy, n } from "@SCL/fields/SCL_secp256r1.sol";
+
+//import modular inversion over prime field defined over curve subgroup of prime order
+import { nModInv } from "@SCL/modular/SCL_modular.sol";
+//import point on curve checking
+import { ec_isOnCurve } from "@SCL/elliptic/SCL_ecOncurve.sol";
+//import point double multiplication and accumulation (RIP7696)
+import "@SCL/elliptic/SCL_mulmuladdX_fullgenW.sol";
+
+library SCL_RIP7212 {
+    function verify(bytes32 message, uint256 r, uint256 s, uint256 qx, uint256 qy) internal view returns (bool) {
+        // check the validity of the signature
+        if (r == 0 || r >= n || s == 0 || s >= n) {
+            return false;
+        }
+
+        // check the public key validity (rejecting not on curve and weak keys)
+        if (ec_isOnCurve(p, a, b, qx, qy) == false) {
+            return false;
+        }
+
+        // calculate the scalars used for the multiplication of the point
+        uint256 sInv = nModInv(s);
+        uint256 scalar_u = mulmod(uint256(message), sInv, n);
+        uint256 scalar_v = mulmod(r, sInv, n);
+        uint256[6] memory Qpa = [qx, qy, p, a, gx, gy];
+
+        uint256 x1;
+        (x1,) = ecGenMulmuladdB4W(Qpa, scalar_u, scalar_v);
+
+        assembly {
+            x1 := addmod(x1, sub(n, r), n)
+        }
+
+        return x1 == 0;
+    }
+}