crypto/x509: keep the raw Subject and Issuer.

X509 names, like everything else X509, are ludicrously general. This
change keeps the raw version of the subject and issuer around for
matching. Since certificates use a distinguished encoding, comparing
the encoding is the same as comparing the values directly. This came
up recently when parsing the NSS built-in certificates which use the
raw subject and issuer for matching trust records to certificates.

R=bradfitz
CC=golang-dev
https://golang.org/cl/5275047

src/pkg/asn1/marshal.go

@@ -464,11 +464,15 @@ func marshalField(out *forkableWriter, v reflect.Value, params fieldParameters)
 
 	if v.Type() == rawValueType {
 		rv := v.Interface().(RawValue)
-		err = marshalTagAndLength(out, tagAndLength{rv.Class, rv.Tag, len(rv.Bytes), rv.IsCompound})
-		if err != nil {
-			return
+		if len(rv.FullBytes) != 0 {
+			_, err = out.Write(rv.FullBytes)
+		} else {
+			err = marshalTagAndLength(out, tagAndLength{rv.Class, rv.Tag, len(rv.Bytes), rv.IsCompound})
+			if err != nil {
+				return
+			}
+			_, err = out.Write(rv.Bytes)
 		}
-		_, err = out.Write(rv.Bytes)
 		return
 	}
 

src/pkg/crypto/x509/cert_pool.go

@@ -5,9 +5,7 @@
 package x509
 
 import (
-	"crypto/x509/pkix"
 	"encoding/pem"
-	"strings"
 )
 
 // Roots is a set of certificates.
@@ -26,10 +24,6 @@ func NewCertPool() *CertPool {
 	}
 }
 
-func nameToKey(name *pkix.Name) string {
-	return strings.Join(name.Country, ",") + "/" + strings.Join(name.Organization, ",") + "/" + strings.Join(name.OrganizationalUnit, ",") + "/" + name.CommonName
-}
-
 // findVerifiedParents attempts to find certificates in s which have signed the
 // given certificate. If no such certificate can be found or the signature
 // doesn't match, it returns nil.
@@ -40,7 +34,7 @@ func (s *CertPool) findVerifiedParents(cert *Certificate) (parents []int) {
 		candidates = s.bySubjectKeyId[string(cert.AuthorityKeyId)]
 	}
 	if len(candidates) == 0 {
-		candidates = s.byName[nameToKey(&cert.Issuer)]
+		candidates = s.byName[string(cert.RawIssuer)]
 	}
 
 	for _, c := range candidates {
@@ -72,7 +66,7 @@ func (s *CertPool) AddCert(cert *Certificate) {
 		keyId := string(cert.SubjectKeyId)
 		s.bySubjectKeyId[keyId] = append(s.bySubjectKeyId[keyId], n)
 	}
-	name := nameToKey(&cert.Subject)
+	name := string(cert.RawSubject)
 	s.byName[name] = append(s.byName[name], n)
 }
 

src/pkg/crypto/x509/pkix/pkix.go

@@ -43,6 +43,8 @@ type Name struct {
 	Locality, Province                        []string
 	StreetAddress, PostalCode                 []string
 	SerialNumber, CommonName                  string
+
+	Names []AttributeTypeAndValue
 }
 
 func (n *Name) FillFromRDNSequence(rdns *RDNSequence) {
@@ -51,6 +53,7 @@ func (n *Name) FillFromRDNSequence(rdns *RDNSequence) {
 			continue
 		}
 		atv := rdn[0]
+		n.Names = append(n.Names, atv)
 		value, ok := atv.Value.(string)
 		if !ok {
 			continue

src/pkg/crypto/x509/verify_test.go

@@ -5,6 +5,7 @@
 package x509
 
 import (
+	"crypto/x509/pkix"
 	"encoding/pem"
 	"os"
 	"strings"
@@ -211,6 +212,10 @@ func chainToDebugString(chain []*Certificate) string {
 	return chainStr
 }
 
+func nameToKey(name *pkix.Name) string {
+	return strings.Join(name.Country, ",") + "/" + strings.Join(name.Organization, ",") + "/" + strings.Join(name.OrganizationalUnit, ",") + "/" + name.CommonName
+}
+
 const verisignRoot = `-----BEGIN CERTIFICATE-----
 MIICPDCCAaUCEHC65B0Q2Sk0tjjKewPMur8wDQYJKoZIhvcNAQECBQAwXzELMAkG
 A1UEBhMCVVMxFzAVBgNVBAoTDlZlcmlTaWduLCBJbmMuMTcwNQYDVQQLEy5DbGFz

src/pkg/crypto/x509/x509.go

@@ -138,9 +138,9 @@ type tbsCertificate struct {
 	Version            int `asn1:"optional,explicit,default:1,tag:0"`
 	SerialNumber       *big.Int
 	SignatureAlgorithm pkix.AlgorithmIdentifier
-	Issuer             pkix.RDNSequence
+	Issuer             asn1.RawValue
 	Validity           validity
-	Subject            pkix.RDNSequence
+	Subject            asn1.RawValue
 	PublicKey          publicKeyInfo
 	UniqueId           asn1.BitString   `asn1:"optional,tag:1"`
 	SubjectUniqueId    asn1.BitString   `asn1:"optional,tag:2"`
@@ -339,6 +339,8 @@ type Certificate struct {
 	Raw                     []byte // Complete ASN.1 DER content (certificate, signature algorithm and signature).
 	RawTBSCertificate       []byte // Certificate part of raw ASN.1 DER content.
 	RawSubjectPublicKeyInfo []byte // DER encoded SubjectPublicKeyInfo.
+	RawSubject              []byte // DER encoded Subject
+	RawIssuer               []byte // DER encoded Issuer
 
 	Signature          []byte
 	SignatureAlgorithm SignatureAlgorithm
@@ -556,6 +558,8 @@ func parseCertificate(in *certificate) (*Certificate, os.Error) {
 	out.Raw = in.Raw
 	out.RawTBSCertificate = in.TBSCertificate.Raw
 	out.RawSubjectPublicKeyInfo = in.TBSCertificate.PublicKey.Raw
+	out.RawSubject = in.TBSCertificate.Subject.FullBytes
+	out.RawIssuer = in.TBSCertificate.Issuer.FullBytes
 
 	out.Signature = in.SignatureValue.RightAlign()
 	out.SignatureAlgorithm =
@@ -575,8 +579,18 @@ func parseCertificate(in *certificate) (*Certificate, os.Error) {
 
 	out.Version = in.TBSCertificate.Version + 1
 	out.SerialNumber = in.TBSCertificate.SerialNumber
-	out.Issuer.FillFromRDNSequence(&in.TBSCertificate.Issuer)
-	out.Subject.FillFromRDNSequence(&in.TBSCertificate.Subject)
+
+	var issuer, subject pkix.RDNSequence
+	if _, err := asn1.Unmarshal(in.TBSCertificate.Subject.FullBytes, &subject); err != nil {
+		return nil, err
+	}
+	if _, err := asn1.Unmarshal(in.TBSCertificate.Issuer.FullBytes, &issuer); err != nil {
+		return nil, err
+	}
+
+	out.Issuer.FillFromRDNSequence(&issuer)
+	out.Subject.FillFromRDNSequence(&subject)
+
 	out.NotBefore = in.TBSCertificate.Validity.NotBefore
 	out.NotAfter = in.TBSCertificate.Validity.NotAfter
 
@@ -968,14 +982,23 @@ func CreateCertificate(rand io.Reader, template, parent *Certificate, pub *rsa.P
 		return
 	}
 
+	asn1Issuer, err := asn1.Marshal(parent.Issuer.ToRDNSequence())
+	if err != nil {
+		return
+	}
+	asn1Subject, err := asn1.Marshal(parent.Subject.ToRDNSequence())
+	if err != nil {
+		return
+	}
+
 	encodedPublicKey := asn1.BitString{BitLength: len(asn1PublicKey) * 8, Bytes: asn1PublicKey}
 	c := tbsCertificate{
 		Version:            2,
 		SerialNumber:       template.SerialNumber,
 		SignatureAlgorithm: pkix.AlgorithmIdentifier{Algorithm: oidSHA1WithRSA},
-		Issuer:             parent.Subject.ToRDNSequence(),
+		Issuer:             asn1.RawValue{FullBytes: asn1Issuer},
 		Validity:           validity{template.NotBefore, template.NotAfter},
-		Subject:            template.Subject.ToRDNSequence(),
+		Subject:            asn1.RawValue{FullBytes: asn1Subject},
 		PublicKey:          publicKeyInfo{nil, pkix.AlgorithmIdentifier{Algorithm: oidRSA}, encodedPublicKey},
 		Extensions:         extensions,
 	}