using glide

vendor/github.com/tjfoc/gmsm/sm2/pkcs1.go

@@ -0,0 +1,132 @@
+/*
+Copyright Suzhou Tongji Fintech Research Institute 2017 All Rights Reserved.
+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 sm2
+
+import (
+	"crypto/rsa"
+	"encoding/asn1"
+	"errors"
+	"math/big"
+)
+
+// pkcs1PrivateKey is a structure which mirrors the PKCS#1 ASN.1 for an RSA private key.
+type pkcs1PrivateKey struct {
+	Version int
+	N       *big.Int
+	E       int
+	D       *big.Int
+	P       *big.Int
+	Q       *big.Int
+	// We ignore these values, if present, because rsa will calculate them.
+	Dp   *big.Int `asn1:"optional"`
+	Dq   *big.Int `asn1:"optional"`
+	Qinv *big.Int `asn1:"optional"`
+
+	AdditionalPrimes []pkcs1AdditionalRSAPrime `asn1:"optional,omitempty"`
+}
+
+type pkcs1AdditionalRSAPrime struct {
+	Prime *big.Int
+
+	// We ignore these values because rsa will calculate them.
+	Exp   *big.Int
+	Coeff *big.Int
+}
+
+// ParsePKCS1PrivateKey returns an RSA private key from its ASN.1 PKCS#1 DER encoded form.
+func ParsePKCS1PrivateKey(der []byte) (*rsa.PrivateKey, error) {
+	var priv pkcs1PrivateKey
+	rest, err := asn1.Unmarshal(der, &priv)
+	if len(rest) > 0 {
+		return nil, asn1.SyntaxError{Msg: "trailing data"}
+	}
+	if err != nil {
+		return nil, err
+	}
+
+	if priv.Version > 1 {
+		return nil, errors.New("x509: unsupported private key version")
+	}
+
+	if priv.N.Sign() <= 0 || priv.D.Sign() <= 0 || priv.P.Sign() <= 0 || priv.Q.Sign() <= 0 {
+		return nil, errors.New("x509: private key contains zero or negative value")
+	}
+
+	key := new(rsa.PrivateKey)
+	key.PublicKey = rsa.PublicKey{
+		E: priv.E,
+		N: priv.N,
+	}
+
+	key.D = priv.D
+	key.Primes = make([]*big.Int, 2+len(priv.AdditionalPrimes))
+	key.Primes[0] = priv.P
+	key.Primes[1] = priv.Q
+	for i, a := range priv.AdditionalPrimes {
+		if a.Prime.Sign() <= 0 {
+			return nil, errors.New("x509: private key contains zero or negative prime")
+		}
+		key.Primes[i+2] = a.Prime
+		// We ignore the other two values because rsa will calculate
+		// them as needed.
+	}
+
+	err = key.Validate()
+	if err != nil {
+		return nil, err
+	}
+	key.Precompute()
+
+	return key, nil
+}
+
+// MarshalPKCS1PrivateKey converts a private key to ASN.1 DER encoded form.
+func MarshalPKCS1PrivateKey(key *rsa.PrivateKey) []byte {
+	key.Precompute()
+
+	version := 0
+	if len(key.Primes) > 2 {
+		version = 1
+	}
+
+	priv := pkcs1PrivateKey{
+		Version: version,
+		N:       key.N,
+		E:       key.PublicKey.E,
+		D:       key.D,
+		P:       key.Primes[0],
+		Q:       key.Primes[1],
+		Dp:      key.Precomputed.Dp,
+		Dq:      key.Precomputed.Dq,
+		Qinv:    key.Precomputed.Qinv,
+	}
+
+	priv.AdditionalPrimes = make([]pkcs1AdditionalRSAPrime, len(key.Precomputed.CRTValues))
+	for i, values := range key.Precomputed.CRTValues {
+		priv.AdditionalPrimes[i].Prime = key.Primes[2+i]
+		priv.AdditionalPrimes[i].Exp = values.Exp
+		priv.AdditionalPrimes[i].Coeff = values.Coeff
+	}
+
+	b, _ := asn1.Marshal(priv)
+	return b
+}
+
+// rsaPublicKey reflects the ASN.1 structure of a PKCS#1 public key.
+type rsaPublicKey struct {
+	N *big.Int
+	E int
+}