Exemple #1
0
func marshalPublicKey(pub interface{}) (publicKeyBytes []byte, publicKeyAlgorithm pkix.AlgorithmIdentifier, err error) {
	switch pub := pub.(type) {
	case *rsa.PublicKey:
		publicKeyBytes, err = asn1.Marshal(rsaPublicKey{
			N: pub.N,
			E: pub.E,
		})
		publicKeyAlgorithm.Algorithm = oidPublicKeyRSA
		// This is a NULL parameters value which is technically
		// superfluous, but most other code includes it and, by
		// doing this, we match their public key hashes.
		publicKeyAlgorithm.Parameters = asn1.RawValue{
			Tag: 5,
		}
	case *ecdsa.PublicKey:
		publicKeyBytes = elliptic.Marshal(pub.Curve, pub.X, pub.Y)
		oid, ok := oidFromNamedCurve(pub.Curve)
		if !ok {
			return nil, pkix.AlgorithmIdentifier{}, errors.New("x509: unsupported elliptic curve")
		}
		publicKeyAlgorithm.Algorithm = oidPublicKeyECDSA
		var paramBytes []byte
		paramBytes, err = asn1.Marshal(oid)
		if err != nil {
			return
		}
		publicKeyAlgorithm.Parameters.FullBytes = paramBytes
	default:
		return nil, pkix.AlgorithmIdentifier{}, errors.New("x509: only RSA and ECDSA public keys supported")
	}

	return publicKeyBytes, publicKeyAlgorithm, nil
}
Exemple #2
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// 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
}
Exemple #3
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func subjectBytes(cert *Certificate) ([]byte, error) {
	if len(cert.RawSubject) > 0 {
		return cert.RawSubject, nil
	}

	return asn1.Marshal(cert.Subject.ToRDNSequence())
}
Exemple #4
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// MarshalECPrivateKey marshals an EC private key into ASN.1, DER format.
func MarshalECPrivateKey(key *ecdsa.PrivateKey) ([]byte, error) {
	oid, ok := oidFromNamedCurve(key.Curve)
	if !ok {
		return nil, errors.New("x509: unknown elliptic curve")
	}
	return asn1.Marshal(ecPrivateKey{
		Version:       1,
		PrivateKey:    key.D.Bytes(),
		NamedCurveOID: oid,
		PublicKey:     asn1.BitString{Bytes: elliptic.Marshal(key.Curve, key.X, key.Y)},
	})
}
Exemple #5
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// CreateCRL returns a DER encoded CRL, signed by this Certificate, that
// contains the given list of revoked certificates.
//
// The only supported key type is RSA (*rsa.PrivateKey for priv).
func (c *Certificate) CreateCRL(rand io.Reader, priv interface{}, revokedCerts []pkix.RevokedCertificate, now, expiry time.Time) (crlBytes []byte, err error) {
	rsaPriv, ok := priv.(*rsa.PrivateKey)
	if !ok {
		return nil, errors.New("x509: non-RSA private keys not supported")
	}
	tbsCertList := pkix.TBSCertificateList{
		Version: 2,
		Signature: pkix.AlgorithmIdentifier{
			Algorithm: oidSignatureSHA1WithRSA,
		},
		Issuer:              c.Subject.ToRDNSequence(),
		ThisUpdate:          now.UTC(),
		NextUpdate:          expiry.UTC(),
		RevokedCertificates: revokedCerts,
	}

	tbsCertListContents, err := asn1.Marshal(tbsCertList)
	if err != nil {
		return
	}

	h := sha1.New()
	h.Write(tbsCertListContents)
	digest := h.Sum(nil)

	signature, err := rsa.SignPKCS1v15(rand, rsaPriv, crypto.SHA1, digest)
	if err != nil {
		return
	}

	return asn1.Marshal(pkix.CertificateList{
		TBSCertList: tbsCertList,
		SignatureAlgorithm: pkix.AlgorithmIdentifier{
			Algorithm: oidSignatureSHA1WithRSA,
		},
		SignatureValue: asn1.BitString{Bytes: signature, BitLength: len(signature) * 8},
	})
}
Exemple #6
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// MarshalPKIXPublicKey serialises a public key to DER-encoded PKIX format.
func MarshalPKIXPublicKey(pub interface{}) ([]byte, error) {
	var publicKeyBytes []byte
	var publicKeyAlgorithm pkix.AlgorithmIdentifier
	var err error

	if publicKeyBytes, publicKeyAlgorithm, err = marshalPublicKey(pub); err != nil {
		return nil, err
	}

	pkix := pkixPublicKey{
		Algo: publicKeyAlgorithm,
		BitString: asn1.BitString{
			Bytes:     publicKeyBytes,
			BitLength: 8 * len(publicKeyBytes),
		},
	}

	ret, _ := asn1.Marshal(pkix)
	return ret, nil
}
Exemple #7
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// CreateCertificate creates a new certificate based on a template. The
// following members of template are used: SerialNumber, Subject, NotBefore,
// NotAfter, KeyUsage, ExtKeyUsage, UnknownExtKeyUsage, BasicConstraintsValid,
// IsCA, MaxPathLen, SubjectKeyId, DNSNames, PermittedDNSDomainsCritical,
// PermittedDNSDomains.
//
// The certificate is signed by parent. If parent is equal to template then the
// certificate is self-signed. The parameter pub is the public key of the
// signee and priv is the private key of the signer.
//
// The returned slice is the certificate in DER encoding.
//
// The only supported key types are RSA and ECDSA (*rsa.PublicKey or
// *ecdsa.PublicKey for pub, *rsa.PrivateKey or *ecdsa.PublicKey for priv).
func CreateCertificate(rand io.Reader, template, parent *Certificate, pub interface{}, priv interface{}) (cert []byte, err error) {
	var publicKeyBytes []byte
	var publicKeyAlgorithm pkix.AlgorithmIdentifier

	if publicKeyBytes, publicKeyAlgorithm, err = marshalPublicKey(pub); err != nil {
		return nil, err
	}

	var signatureAlgorithm pkix.AlgorithmIdentifier
	var hashFunc crypto.Hash

	switch priv := priv.(type) {
	case *rsa.PrivateKey:
		signatureAlgorithm.Algorithm = oidSignatureSHA1WithRSA
		hashFunc = crypto.SHA1
	case *ecdsa.PrivateKey:
		switch priv.Curve {
		case elliptic.P224(), elliptic.P256():
			hashFunc = crypto.SHA256
			signatureAlgorithm.Algorithm = oidSignatureECDSAWithSHA256
		case elliptic.P384():
			hashFunc = crypto.SHA384
			signatureAlgorithm.Algorithm = oidSignatureECDSAWithSHA384
		case elliptic.P521():
			hashFunc = crypto.SHA512
			signatureAlgorithm.Algorithm = oidSignatureECDSAWithSHA512
		default:
			return nil, errors.New("x509: unknown elliptic curve")
		}
	default:
		return nil, errors.New("x509: only RSA and ECDSA private keys supported")
	}

	if err != nil {
		return
	}

	if len(parent.SubjectKeyId) > 0 {
		template.AuthorityKeyId = parent.SubjectKeyId
	}

	extensions, err := buildExtensions(template)
	if err != nil {
		return
	}

	asn1Issuer, err := subjectBytes(parent)
	if err != nil {
		return
	}

	asn1Subject, err := subjectBytes(template)
	if err != nil {
		return
	}

	encodedPublicKey := asn1.BitString{BitLength: len(publicKeyBytes) * 8, Bytes: publicKeyBytes}
	c := tbsCertificate{
		Version:            2,
		SerialNumber:       template.SerialNumber,
		SignatureAlgorithm: signatureAlgorithm,
		Issuer:             asn1.RawValue{FullBytes: asn1Issuer},
		Validity:           validity{template.NotBefore.UTC(), template.NotAfter.UTC()},
		Subject:            asn1.RawValue{FullBytes: asn1Subject},
		PublicKey:          publicKeyInfo{nil, publicKeyAlgorithm, encodedPublicKey},
		Extensions:         extensions,
	}

	tbsCertContents, err := asn1.Marshal(c)
	if err != nil {
		return
	}

	c.Raw = tbsCertContents

	h := hashFunc.New()
	h.Write(tbsCertContents)
	digest := h.Sum(nil)

	var signature []byte

	switch priv := priv.(type) {
	case *rsa.PrivateKey:
		signature, err = rsa.SignPKCS1v15(rand, priv, hashFunc, digest)
	case *ecdsa.PrivateKey:
		var r, s *big.Int
		if r, s, err = ecdsa.Sign(rand, priv, digest); err == nil {
			signature, err = asn1.Marshal(ecdsaSignature{r, s})
		}
	default:
		panic("internal error")
	}

	if err != nil {
		return
	}

	cert, err = asn1.Marshal(certificate{
		nil,
		c,
		signatureAlgorithm,
		asn1.BitString{Bytes: signature, BitLength: len(signature) * 8},
	})
	return
}
Exemple #8
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func buildExtensions(template *Certificate) (ret []pkix.Extension, err error) {
	ret = make([]pkix.Extension, 10 /* maximum number of elements. */)
	n := 0

	if template.KeyUsage != 0 &&
		!oidInExtensions(oidExtensionKeyUsage, template.ExtraExtensions) {
		ret[n].Id = oidExtensionKeyUsage
		ret[n].Critical = true

		var a [2]byte
		a[0] = reverseBitsInAByte(byte(template.KeyUsage))
		a[1] = reverseBitsInAByte(byte(template.KeyUsage >> 8))

		l := 1
		if a[1] != 0 {
			l = 2
		}

		ret[n].Value, err = asn1.Marshal(asn1.BitString{Bytes: a[0:l], BitLength: l * 8})
		if err != nil {
			return
		}
		n++
	}

	if (len(template.ExtKeyUsage) > 0 || len(template.UnknownExtKeyUsage) > 0) &&
		!oidInExtensions(oidExtensionExtendedKeyUsage, template.ExtraExtensions) {
		ret[n].Id = oidExtensionExtendedKeyUsage

		var oids []asn1.ObjectIdentifier
		for _, u := range template.ExtKeyUsage {
			if oid, ok := oidFromExtKeyUsage(u); ok {
				oids = append(oids, oid)
			} else {
				panic("internal error")
			}
		}

		oids = append(oids, template.UnknownExtKeyUsage...)

		ret[n].Value, err = asn1.Marshal(oids)
		if err != nil {
			return
		}
		n++
	}

	if template.BasicConstraintsValid && !oidInExtensions(oidExtensionBasicConstraints, template.ExtraExtensions) {
		ret[n].Id = oidExtensionBasicConstraints
		ret[n].Value, err = asn1.Marshal(basicConstraints{template.IsCA, template.MaxPathLen})
		ret[n].Critical = true
		if err != nil {
			return
		}
		n++
	}

	if len(template.SubjectKeyId) > 0 && !oidInExtensions(oidExtensionSubjectKeyId, template.ExtraExtensions) {
		ret[n].Id = oidExtensionSubjectKeyId
		ret[n].Value, err = asn1.Marshal(template.SubjectKeyId)
		if err != nil {
			return
		}
		n++
	}

	if len(template.AuthorityKeyId) > 0 && !oidInExtensions(oidExtensionAuthorityKeyId, template.ExtraExtensions) {
		ret[n].Id = oidExtensionAuthorityKeyId
		ret[n].Value, err = asn1.Marshal(authKeyId{template.AuthorityKeyId})
		if err != nil {
			return
		}
		n++
	}

	if (len(template.OCSPServer) > 0 || len(template.IssuingCertificateURL) > 0) &&
		!oidInExtensions(oidExtensionAuthorityInfoAccess, template.ExtraExtensions) {
		ret[n].Id = oidExtensionAuthorityInfoAccess
		var aiaValues []authorityInfoAccess
		for _, name := range template.OCSPServer {
			aiaValues = append(aiaValues, authorityInfoAccess{
				Method:   oidAuthorityInfoAccessOcsp,
				Location: asn1.RawValue{Tag: 6, Class: 2, Bytes: []byte(name)},
			})
		}
		for _, name := range template.IssuingCertificateURL {
			aiaValues = append(aiaValues, authorityInfoAccess{
				Method:   oidAuthorityInfoAccessIssuers,
				Location: asn1.RawValue{Tag: 6, Class: 2, Bytes: []byte(name)},
			})
		}
		ret[n].Value, err = asn1.Marshal(aiaValues)
		if err != nil {
			return
		}
		n++
	}

	if (len(template.DNSNames) > 0 || len(template.EmailAddresses) > 0 || len(template.IPAddresses) > 0) &&
		!oidInExtensions(oidExtensionSubjectAltName, template.ExtraExtensions) {
		ret[n].Id = oidExtensionSubjectAltName
		var rawValues []asn1.RawValue
		for _, name := range template.DNSNames {
			rawValues = append(rawValues, asn1.RawValue{Tag: 2, Class: 2, Bytes: []byte(name)})
		}
		for _, email := range template.EmailAddresses {
			rawValues = append(rawValues, asn1.RawValue{Tag: 1, Class: 2, Bytes: []byte(email)})
		}
		for _, rawIP := range template.IPAddresses {
			// If possible, we always want to encode IPv4 addresses in 4 bytes.
			ip := rawIP.To4()
			if ip == nil {
				ip = rawIP
			}
			rawValues = append(rawValues, asn1.RawValue{Tag: 7, Class: 2, Bytes: ip})
		}
		ret[n].Value, err = asn1.Marshal(rawValues)
		if err != nil {
			return
		}
		n++
	}

	if len(template.PolicyIdentifiers) > 0 &&
		!oidInExtensions(oidExtensionCertificatePolicies, template.ExtraExtensions) {
		ret[n].Id = oidExtensionCertificatePolicies
		policies := make([]policyInformation, len(template.PolicyIdentifiers))
		for i, policy := range template.PolicyIdentifiers {
			policies[i].Policy = policy
		}
		ret[n].Value, err = asn1.Marshal(policies)
		if err != nil {
			return
		}
		n++
	}

	if len(template.PermittedDNSDomains) > 0 &&
		!oidInExtensions(oidExtensionNameConstraints, template.ExtraExtensions) {
		ret[n].Id = oidExtensionNameConstraints
		ret[n].Critical = template.PermittedDNSDomainsCritical

		var out nameConstraints
		out.Permitted = make([]generalSubtree, len(template.PermittedDNSDomains))
		for i, permitted := range template.PermittedDNSDomains {
			out.Permitted[i] = generalSubtree{Name: permitted}
		}
		ret[n].Value, err = asn1.Marshal(out)
		if err != nil {
			return
		}
		n++
	}

	if len(template.CRLDistributionPoints) > 0 &&
		!oidInExtensions(oidExtensionCRLDistributionPoints, template.ExtraExtensions) {
		ret[n].Id = oidExtensionCRLDistributionPoints

		var crlDp []distributionPoint
		for _, name := range template.CRLDistributionPoints {
			rawFullName, _ := asn1.Marshal(asn1.RawValue{Tag: 6, Class: 2, Bytes: []byte(name)})

			dp := distributionPoint{
				DistributionPoint: distributionPointName{
					FullName: asn1.RawValue{Tag: 0, Class: 2, Bytes: rawFullName},
				},
			}
			crlDp = append(crlDp, dp)
		}

		ret[n].Value, err = asn1.Marshal(crlDp)
		if err != nil {
			return
		}
		n++
	}

	// Adding another extension here? Remember to update the maximum number
	// of elements in the make() at the top of the function.

	return append(ret[:n], template.ExtraExtensions...), nil
}