// MarshalPKIXPublicKey serialises a public key to DER-encoded PKIX format.
func MarshalPKIXPublicKey(pub interface{}) ([]byte, os.Error) {
var pubBytes []byte
switch pub := pub.(type) {
case *rsa.PublicKey:
pubBytes, _ = asn1.Marshal(rsaPublicKey{
N: pub.N,
E: pub.E,
})
default:
return nil, os.NewError("MarshalPKIXPublicKey: unknown public key type")
}
pkix := pkixPublicKey{
Algo: pkix.AlgorithmIdentifier{
Algorithm: []int{1, 2, 840, 113549, 1, 1, 1},
// 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.
Parameters: asn1.RawValue{
Tag: 5,
},
},
BitString: asn1.BitString{
Bytes: pubBytes,
BitLength: 8 * len(pubBytes),
},
}
ret, _ := asn1.Marshal(pkix)
return ret, nil
}
// CreateCRL returns a DER encoded CRL, signed by this Certificate, that
// contains the given list of revoked certificates.
func (c *Certificate) CreateCRL(rand io.Reader, priv *rsa.PrivateKey, revokedCerts []pkix.RevokedCertificate, now, expiry *time.Time) (crlBytes []byte, err os.Error) {
tbsCertList := pkix.TBSCertificateList{
Version: 2,
Signature: pkix.AlgorithmIdentifier{
Algorithm: oidSignatureSHA1WithRSA,
},
Issuer: c.Subject.ToRDNSequence(),
ThisUpdate: now,
NextUpdate: expiry,
RevokedCertificates: revokedCerts,
}
tbsCertListContents, err := asn1.Marshal(tbsCertList)
if err != nil {
return
}
h := sha1.New()
h.Write(tbsCertListContents)
digest := h.Sum()
signature, err := rsa.SignPKCS1v15(rand, priv, 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},
})
}
func GetStringValue(oid asn1.ObjectIdentifier, community string, addr net.UDPAddr) (string, os.Error) {
conn, err := net.DialUDP("udp", nil, &addr)
if err != nil {
return "", err
}
defer conn.Close()
r := PDU{
RequestId: 199,
ErrorStatus: 0,
ErrorIndex: 0,
VarBindList: []VarBind{
VarBind{
Name: oid,
Value: Null(),
},
},
}
data, err := asn1.Marshal(r)
if err != nil {
return "", err
}
m := Message{
Version: 1,
Community: NewOctetString(community),
Data: Any(data),
}
data, err = asn1.Marshal(m)
if err != nil {
return "", err
}
_, err = conn.Write(data)
if err != nil {
return "", err
}
data = make([]byte, 1500)
read, err := conn.Read(data)
if err != nil {
return "", err
}
pdu, err := decode(data[:read])
if err != nil {
return "", err
}
switch response := pdu.(type) {
case *PDU:
s, ok := response.VarBindList[0].Value.([]byte)
if !ok {
return "", fmt.Errorf("Invalid value returned")
}
return string(s), nil
}
return "", nil
}
// CreateSelfSignedCertificate creates a new certificate based on
// a template. The following members of template are used: SerialNumber,
// Subject, NotBefore, NotAfter, KeyUsage, 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.
func CreateCertificate(rand io.Reader, template, parent *Certificate, pub *rsa.PublicKey, priv *rsa.PrivateKey) (cert []byte, err os.Error) {
asn1PublicKey, err := asn1.Marshal(rsaPublicKey{
N: asn1.RawValue{Tag: 2, Bytes: pub.N.Bytes()},
E: pub.E,
})
if err != nil {
return
}
if len(parent.SubjectKeyId) > 0 {
template.AuthorityKeyId = parent.SubjectKeyId
}
extensions, err := buildExtensions(template)
if err != nil {
return
}
encodedPublicKey := asn1.BitString{BitLength: len(asn1PublicKey) * 8, Bytes: asn1PublicKey}
c := tbsCertificate{
Version: 2,
SerialNumber: asn1.RawValue{Bytes: template.SerialNumber, Tag: 2},
SignatureAlgorithm: algorithmIdentifier{Algorithm: oidSHA1WithRSA},
Issuer: parent.Subject.toRDNSequence(),
Validity: validity{template.NotBefore, template.NotAfter},
Subject: template.Subject.toRDNSequence(),
PublicKey: publicKeyInfo{nil, algorithmIdentifier{Algorithm: oidRSA}, encodedPublicKey},
Extensions: extensions,
}
tbsCertContents, err := asn1.Marshal(c)
if err != nil {
return
}
c.Raw = tbsCertContents
h := sha1.New()
h.Write(tbsCertContents)
digest := h.Sum()
signature, err := rsa.SignPKCS1v15(rand, priv, crypto.SHA1, digest)
if err != nil {
return
}
cert, err = asn1.Marshal(certificate{
nil,
c,
algorithmIdentifier{Algorithm: oidSHA1WithRSA},
asn1.BitString{Bytes: signature, BitLength: len(signature) * 8},
})
return
}
// 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
}
// 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: rawValueForBig(key.N),
E: key.PublicKey.E,
D: rawValueForBig(key.D),
P: rawValueForBig(key.Primes[0]),
Q: rawValueForBig(key.Primes[1]),
Dp: rawValueForBig(key.Precomputed.Dp),
Dq: rawValueForBig(key.Precomputed.Dq),
Qinv: rawValueForBig(key.Precomputed.Qinv),
}
priv.AdditionalPrimes = make([]pkcs1AdditionalRSAPrime, len(key.Precomputed.CRTValues))
for i, values := range key.Precomputed.CRTValues {
priv.AdditionalPrimes[i].Prime = rawValueForBig(key.Primes[2+i])
priv.AdditionalPrimes[i].Exp = rawValueForBig(values.Exp)
priv.AdditionalPrimes[i].Coeff = rawValueForBig(values.Coeff)
}
b, _ := asn1.Marshal(priv)
return b
}
func TestSNMPGetNextRequest(t *testing.T) {
r := PDU{
RequestId: 199,
ErrorStatus: 0,
ErrorIndex: 0,
VarBindList: []VarBind{
VarBind{
Name: []int{1, 3, 6, 1, 2, 1, 1, 1, 0},
Value: Null(),
},
},
}
data, err := asn1.Marshal(r)
if err != nil {
t.Error(err)
}
m := Message{
Version: 1,
Community: NewOctetString("timer"),
Data: Any(data),
}
data, err = asn1.Marshal(m)
if err != nil {
t.Error(err)
}
addr := net.UDPAddr{net.IPv4(192, 168, 1, 254), 161}
conn, err := net.DialUDP("udp4", nil, &addr)
if err != nil {
t.Error(err)
}
defer conn.Close()
written, err := conn.Write(data)
if err != nil {
t.Error(err)
}
if written != len(data) {
t.Errorf("did not write the full data %d", written)
}
}
// MarshalPKCS1PrivateKey converts a private key to ASN.1 DER encoded form.
func MarshalPKCS1PrivateKey(key *rsa.PrivateKey) []byte {
priv := pkcs1PrivateKey{
Version: 1,
N: asn1.RawValue{Tag: 2, Bytes: key.PublicKey.N.Bytes()},
E: key.PublicKey.E,
D: asn1.RawValue{Tag: 2, Bytes: key.D.Bytes()},
P: asn1.RawValue{Tag: 2, Bytes: key.P.Bytes()},
Q: asn1.RawValue{Tag: 2, Bytes: key.Q.Bytes()},
}
b, _ := asn1.Marshal(priv)
return b
}
func buildExtensions(template *Certificate) (ret []extension, err os.Error) {
ret = make([]extension, 6 /* maximum number of elements. */)
n := 0
if template.KeyUsage != 0 {
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 template.BasicConstraintsValid {
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 {
ret[n].Id = oidExtensionSubjectKeyId
ret[n].Value, err = asn1.Marshal(template.SubjectKeyId)
if err != nil {
return
}
n++
}
if len(template.AuthorityKeyId) > 0 {
ret[n].Id = oidExtensionAuthorityKeyId
ret[n].Value, err = asn1.Marshal(authKeyId{template.AuthorityKeyId})
if err != nil {
return
}
n++
}
if len(template.DNSNames) > 0 {
ret[n].Id = oidExtensionSubjectAltName
rawValues := make([]asn1.RawValue, len(template.DNSNames))
for i, name := range template.DNSNames {
rawValues[i] = asn1.RawValue{Tag: 2, Class: 2, Bytes: []byte(name)}
}
ret[n].Value, err = asn1.Marshal(rawValues)
if err != nil {
return
}
n++
}
if len(template.PolicyIdentifiers) > 0 {
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++
}
// Adding another extension here? Remember to update the maximum number
// of elements in the make() at the top of the function.
return ret[0:n], nil
}