Merge pull request #30 from unravelin/master

Support 31 and 32 byte elliptic curves
dvsekhvalnov · Nov 2, 2021 · feb89cf · feb89cf
2 parents b09cfaf + ffc75f2
commit feb89cf
Showing 1 changed file with 41 additions and 37 deletions.
diff --git a/keys/ecc/ecc.go b/keys/ecc/ecc.go
@@ -2,44 +2,44 @@
 package ecc
 
 import (
-	"math/big"
 	"crypto/ecdsa"
-	"crypto/elliptic"	
-    "crypto/x509"
-	"encoding/pem"	
+	"crypto/elliptic"
+	"crypto/x509"
+	"encoding/pem"
 	"errors"
+	"math/big"
 )
 
 // ReadPublic loads ecdsa.PublicKey from given PKCS1 X509 or PKIX blobs
-func ReadPublic(raw []byte) (key *ecdsa.PublicKey,err error) {
+func ReadPublic(raw []byte) (key *ecdsa.PublicKey, err error) {
 	var encoded *pem.Block
-	
+
 	if encoded, _ = pem.Decode(raw); encoded == nil {
 		return nil, errors.New("Ecc.ReadPublic(): Key must be PEM encoded PKCS1 X509 certificate or PKIX EC public key")
 	}
-		
+
 	var parsedKey interface{}
 	var cert *x509.Certificate
-	
+
 	if parsedKey, err = x509.ParsePKIXPublicKey(encoded.Bytes); err != nil {
-		if cert,err = x509.ParseCertificate(encoded.Bytes);err!=nil {
+		if cert, err = x509.ParseCertificate(encoded.Bytes); err != nil {
 			return nil, err
 		}
-		
-		parsedKey=cert.PublicKey
+
+		parsedKey = cert.PublicKey
 	}
-	
+
 	var ok bool
-	
+
 	if key, ok = parsedKey.(*ecdsa.PublicKey); !ok {
 		return nil, errors.New("Ecc.ReadPublic(): Key is not a valid *ecdsa.PublicKey")
 	}
-	
+
 	return key, nil
 }
 
 // ReadPrivate loads ecdsa.PrivateKey from given PKCS1 or PKCS8 blobs
-func ReadPrivate(raw []byte) (key *ecdsa.PrivateKey,err error) {
+func ReadPrivate(raw []byte) (key *ecdsa.PrivateKey, err error) {
 	var encoded *pem.Block
 
 	if encoded, _ = pem.Decode(raw); encoded == nil {
@@ -48,41 +48,45 @@ func ReadPrivate(raw []byte) (key *ecdsa.PrivateKey,err error) {
 
 	var parsedKey interface{}
 
-	if parsedKey,err=x509.ParseECPrivateKey(encoded.Bytes);err!=nil {
-		if parsedKey, err = x509.ParsePKCS8PrivateKey(encoded.Bytes);err!=nil {
-			return nil,err
+	if parsedKey, err = x509.ParseECPrivateKey(encoded.Bytes); err != nil {
+		if parsedKey, err = x509.ParsePKCS8PrivateKey(encoded.Bytes); err != nil {
+			return nil, err
 		}
 	}
 
 	var ok bool
-		
-	if key,ok=parsedKey.(*ecdsa.PrivateKey);!ok {
+
+	if key, ok = parsedKey.(*ecdsa.PrivateKey); !ok {
 		return nil, errors.New("Ecc.ReadPrivate(): Key is not valid *ecdsa.PrivateKey")
 	}
-	
-	return key,nil
+
+	return key, nil
 }
 
 // NewPublic constructs ecdsa.PublicKey from given (X,Y)
-func NewPublic(x,y []byte) (*ecdsa.PublicKey) {
-	return &ecdsa.PublicKey{ Curve: curve(len(x)), 
-							 X:new(big.Int).SetBytes(x), 
-							 Y:new(big.Int).SetBytes(y) }
+func NewPublic(x, y []byte) *ecdsa.PublicKey {
+	return &ecdsa.PublicKey{Curve: curve(len(x)),
+		X: new(big.Int).SetBytes(x),
+		Y: new(big.Int).SetBytes(y)}
 }
 
 // NewPrivate constructs ecdsa.PrivateKey from given (X,Y) and D
-func NewPrivate(x,y,d []byte) (*ecdsa.PrivateKey) {
-	return &ecdsa.PrivateKey {D:new(big.Int).SetBytes(d),
-							  PublicKey: ecdsa.PublicKey{ Curve:curve(len(x)),
-								  						  X:new(big.Int).SetBytes(x), 
-														  Y:new(big.Int).SetBytes(y)}}
+func NewPrivate(x, y, d []byte) *ecdsa.PrivateKey {
+	return &ecdsa.PrivateKey{D: new(big.Int).SetBytes(d),
+		PublicKey: ecdsa.PublicKey{Curve: curve(len(x)),
+			X: new(big.Int).SetBytes(x),
+			Y: new(big.Int).SetBytes(y)}}
 }
 
-func curve(size int) (elliptic.Curve) {
+func curve(size int) elliptic.Curve {
 	switch size {
-		case 32: return elliptic.P256()
-		case 48: return elliptic.P384()
-		case 65,66: return elliptic.P521() //adjust for P-521 curve, which can be 65 or 66 bytes
-		default: return nil //unsupported curve
+	case 31, 32:
+		return elliptic.P256()
+	case 48:
+		return elliptic.P384()
+	case 65, 66:
+		return elliptic.P521() //adjust for P-521 curve, which can be 65 or 66 bytes
+	default:
+		return nil //unsupported curve
 	}
-}
+}