Shorter unified curve argument name

[gogost.git] / gost3410 / public.go

diff --git a/gost3410/public.go b/gost3410/public.go
index 675431cf816f72bc4448c5916ef1fe3fb564ad9c..85d3557bfe03c7506e4417ed258c6e62665aa46f 100644 (file)
--- a/gost3410/public.go
+++ b/gost3410/public.go
@@ -1,5 +1,5 @@
 // GoGOST -- Pure Go GOST cryptographic functions library
-// Copyright (C) 2015-2020 Sergey Matveev <stargrave@stargrave.org>
+// Copyright (C) 2015-2021 Sergey Matveev <stargrave@stargrave.org>
 //
 // This program is free software: you can redistribute it and/or modify
 // it under the terms of the GNU General Public License as published by
@@ -16,19 +16,20 @@
 package gost3410
 
 import (
+       "crypto"
        "fmt"
        "math/big"
 )
 
 type PublicKey struct {
-       C    *Curve
-       Mode Mode
-       X    *big.Int
-       Y    *big.Int
+       C *Curve
+       X *big.Int
+       Y *big.Int
 }
 
-func NewPublicKey(curve *Curve, mode Mode, raw []byte) (*PublicKey, error) {
-       key := make([]byte, 2*int(mode))
+func NewPublicKey(c *Curve, raw []byte) (*PublicKey, error) {
+       pointSize := c.PointSize()
+       key := make([]byte, 2*pointSize)
        if len(raw) != len(key) {
                return nil, fmt.Errorf("gogost/gost3410: len(key) != %d", len(key))
        }
@@ -36,28 +37,29 @@ func NewPublicKey(curve *Curve, mode Mode, raw []byte) (*PublicKey, error) {
                key[i] = raw[len(raw)-i-1]
        }
        return &PublicKey{
-               curve,
-               mode,
-               bytes2big(key[int(mode) : 2*int(mode)]),
-               bytes2big(key[:int(mode)]),
+               c,
+               bytes2big(key[pointSize : 2*pointSize]),
+               bytes2big(key[:pointSize]),
        }, nil
 }
 
 func (pub *PublicKey) Raw() []byte {
+       pointSize := pub.C.PointSize()
        raw := append(
-               pad(pub.Y.Bytes(), int(pub.Mode)),
-               pad(pub.X.Bytes(), int(pub.Mode))...,
+               pad(pub.Y.Bytes(), pointSize),
+               pad(pub.X.Bytes(), pointSize)...,
        )
        reverse(raw)
        return raw
 }
 
 func (pub *PublicKey) VerifyDigest(digest, signature []byte) (bool, error) {
-       if len(signature) != 2*int(pub.Mode) {
-               return false, fmt.Errorf("gogost/gost3410: len(signature) != %d", 2*int(pub.Mode))
+       pointSize := pub.C.PointSize()
+       if len(signature) != 2*pointSize {
+               return false, fmt.Errorf("gogost/gost3410: len(signature) != %d", 2*pointSize)
        }
-       s := bytes2big(signature[:pub.Mode])
-       r := bytes2big(signature[pub.Mode:])
+       s := bytes2big(signature[:pointSize])
+       r := bytes2big(signature[pointSize:])
        if r.Cmp(zero) <= 0 ||
                r.Cmp(pub.C.Q) >= 0 ||
                s.Cmp(zero) <= 0 ||
@@ -106,3 +108,11 @@ func (pub *PublicKey) VerifyDigest(digest, signature []byte) (bool, error) {
        lm.Mod(lm, pub.C.Q)
        return lm.Cmp(r) == 0, nil
 }
+
+func (our *PublicKey) Equal(theirKey crypto.PublicKey) bool {
+       their, ok := theirKey.(*PublicKey)
+       if !ok {
+               return false
+       }
+       return our.X.Cmp(their.X) == 0 && our.Y.Cmp(their.Y) == 0 && our.C.Equal(their.C)
+}