1 // Copyright 2011 The Go Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style
3 // license that can be found in the LICENSE file.
14 // pkcs1PrivateKey is a structure which mirrors the PKCS#1 ASN.1 for an RSA private key.
15 type pkcs1PrivateKey struct {
22 // We ignore these values, if present, because rsa will calculate them.
23 Dp *big.Int `asn1:"optional"`
24 Dq *big.Int `asn1:"optional"`
25 Qinv *big.Int `asn1:"optional"`
27 AdditionalPrimes []pkcs1AdditionalRSAPrime `asn1:"optional"`
30 type pkcs1AdditionalRSAPrime struct {
33 // We ignore these values because rsa will calculate them.
38 // ParsePKCS1PrivateKey returns an RSA private key from its ASN.1 PKCS#1 DER encoded form.
39 func ParsePKCS1PrivateKey(der []byte) (key *rsa.PrivateKey, err os.Error) {
40 var priv pkcs1PrivateKey
41 rest, err := asn1.Unmarshal(der, &priv)
43 err = asn1.SyntaxError{"trailing data"}
51 return nil, os.NewError("x509: unsupported private key version")
54 if priv.N.Sign() <= 0 || priv.D.Sign() <= 0 || priv.P.Sign() <= 0 || priv.Q.Sign() <= 0 {
55 return nil, os.NewError("private key contains zero or negative value")
58 key = new(rsa.PrivateKey)
59 key.PublicKey = rsa.PublicKey{
65 key.Primes = make([]*big.Int, 2+len(priv.AdditionalPrimes))
66 key.Primes[0] = priv.P
67 key.Primes[1] = priv.Q
68 for i, a := range priv.AdditionalPrimes {
69 if a.Prime.Sign() <= 0 {
70 return nil, os.NewError("private key contains zero or negative prime")
72 key.Primes[i+2] = a.Prime
73 // We ignore the other two values because rsa will calculate
86 // MarshalPKCS1PrivateKey converts a private key to ASN.1 DER encoded form.
87 func MarshalPKCS1PrivateKey(key *rsa.PrivateKey) []byte {
91 if len(key.Primes) > 2 {
95 priv := pkcs1PrivateKey{
102 Dp: key.Precomputed.Dp,
103 Dq: key.Precomputed.Dq,
104 Qinv: key.Precomputed.Qinv,
107 priv.AdditionalPrimes = make([]pkcs1AdditionalRSAPrime, len(key.Precomputed.CRTValues))
108 for i, values := range key.Precomputed.CRTValues {
109 priv.AdditionalPrimes[i].Prime = key.Primes[2+i]
110 priv.AdditionalPrimes[i].Exp = values.Exp
111 priv.AdditionalPrimes[i].Coeff = values.Coeff
114 b, _ := asn1.Marshal(priv)
118 // rsaPublicKey reflects the ASN.1 structure of a PKCS#1 public key.
119 type rsaPublicKey struct {