docs: update documentation for ecdsa and eddsa

std/signature/ecdsa/doc.go

@@ -0,0 +1,13 @@
+// Package ecdsa implements ECDSA signature verification over any elliptic curve.
+//
+// The package depends on the [emulated/sw_emulated] package for elliptic curve
+// group operations using non-native arithmetic. Thus we can verify ECDSA
+// signatures over any curve. The cost for a single secp256k1 signature
+// verification in a BN254-SNARK is approximately 122k constraints in R1CS and
+// 453k constraints in PLONKish.
+//
+// See [ECDSA] for the signature verification algorithm.
+//
+// [ECDSA]:
+// https://en.wikipedia.org/wiki/Elliptic_Curve_Digital_Signature_Algorithm
+package ecdsa

std/signature/ecdsa/ecdsa.go

@@ -1,16 +1,3 @@
-/*
-Package ecdsa implements ECDSA signature verification over any elliptic curve.
-
-The package depends on the [emulated/sw_emulated] package for elliptic curve group
-operations using non-native arithmetic. Thus we can verify ECDSA signatures over
-any curve. The cost for a single secp256k1 signature verification is
-approximately 4M constraints in R1CS and 10M constraints in PLONKish.
-
-See [ECDSA] for the signature verification algorithm.
-
-[ECDSA]:
-https://en.wikipedia.org/wiki/Elliptic_Curve_Digital_Signature_Algorithm
-*/
 package ecdsa
 
 import (

std/signature/eddsa/doc.go

@@ -0,0 +1,15 @@
+// Package eddsa implements EdDSA signature verification over twisted Edwards
+// elliptic curves available in gnark and gnark-crypto. These are the so-called
+// "embedded curves" (e.g. Baby-Jubjub, Bandersnatch...) defined over the scalar
+// field of the pairing-friendly SNARK curves (e.g. BN254, BLS12-381...)
+//
+// The package depends on the [native/twistededwards] package for elliptic
+// curve group operations in twisted Edwards form using native arithmetic. The
+// cost for a single baby-jubjub signature verification in a BN254-SNARK is
+// approximately 7k constraints in R1CS and 11k constraints in PLONKish.
+//
+// See [EdDSA] for the signature verification algorithm.
+//
+// [EdDSA]:
+// https://en.wikipedia.org/wiki/EdDSA
+package eddsa

std/signature/eddsa/eddsa.go

@@ -1,20 +1,3 @@
-/*
-Copyright © 2020 ConsenSys
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-// Package eddsa provides a ZKP-circuit function to verify a EdDSA signature.
 package eddsa
 
 import (