add URI attribute to <Reference>

signature.go

@@ -10,6 +10,18 @@ import (
 type Method struct {
 	Algorithm string `xml:",attr"`
 }
+type Reference struct {
+	URI                 string   `xml:"URI,attr"`
+	ReferenceTransforms []Method `xml:"Transforms>Transform"`
+	DigestMethod        Method   `xml:"DigestMethod"`
+	DigestValue         string   `xml:"DigestValue"`
+}
+
+type SignedInfo struct {
+	CanonicalizationMethod Method    `xml:"CanonicalizationMethod"`
+	SignatureMethod        Method    `xml:"SignatureMethod"`
+	Reference              Reference `xml:"Reference"`
+}
 
 // Signature is a model for the Signature object specified by XMLDSIG. This is
 // convenience object when constructing XML that you'd like to sign. For example:
@@ -26,12 +38,7 @@ type Method struct {
 //
 type Signature struct {
 	XMLName         xml.Name `xml:"http://www.w3.org/2000/09/xmldsig# Signature"`
-
-	CanonicalizationMethod Method             `xml:"SignedInfo>CanonicalizationMethod"`
-	SignatureMethod        Method             `xml:"SignedInfo>SignatureMethod"`
-	ReferenceTransforms    []Method           `xml:"SignedInfo>Reference>Transforms>Transform"`
-	DigestMethod           Method             `xml:"SignedInfo>Reference>DigestMethod"`
-	DigestValue            string             `xml:"SignedInfo>Reference>DigestValue"`
+	SignedInfo      SignedInfo
 	SignatureValue  string             `xml:"SignatureValue"`
 	KeyName         string             `xml:"KeyInfo>KeyName,omitempty"`
 	X509Certificate *SignatureX509Data `xml:"KeyInfo>X509Data,omitempty"`
@@ -50,18 +57,22 @@ func DefaultSignature(pemEncodedPublicKey []byte) Signature {
 	certStr := base64.StdEncoding.EncodeToString(pemBlock.Bytes)
 
 	return Signature{
+		SignedInfo: SignedInfo{
 			CanonicalizationMethod: Method{
 				Algorithm: "http://www.w3.org/TR/2001/REC-xml-c14n-20010315",
 			},
 			SignatureMethod: Method{
 				Algorithm: "http://www.w3.org/2000/09/xmldsig#rsa-sha1",
 			},
+			Reference: Reference{
 				ReferenceTransforms: []Method{
 					Method{Algorithm: "http://www.w3.org/2000/09/xmldsig#enveloped-signature"},
 				},
 				DigestMethod: Method{
 					Algorithm: "http://www.w3.org/2000/09/xmldsig#sha1",
 				},
+			},
+		},
 		X509Certificate: &SignatureX509Data{
 			X509Certificate: certStr,
 		},