XMLDSIG from .NET Core. (#6154)

12 files changed, 877 insertions, 1796 deletions

diff --git a/mcs/class/System.Security/Makefile b/mcs/class/System.Security/Makefile
index ae2de1a6370..04a3bea4d1e 100644
--- a/mcs/class/System.Security/Makefile
+++ b/mcs/class/System.Security/Makefile
@@ -8,6 +8,7 @@ MONO_SECURITY=Mono.Security
 endif
 
 LIBRARY = System.Security.dll
+API_BIN_REFS := System.Numerics
 LIB_REFS = secxml/System bare/System.Xml $(MONO_SECURITY)
 KEYFILE = ../msfinal.pub
 LIB_MCS_FLAGS = \
diff --git a/mcs/class/System.Security/System.Security.Cryptography.Xml/KeyInfoX509Data.cs b/mcs/class/System.Security/System.Security.Cryptography.Xml/KeyInfoX509Data.cs
deleted file mode 100644
index 74280cb9151..00000000000
--- a/mcs/class/System.Security/System.Security.Cryptography.Xml/KeyInfoX509Data.cs
+++ /dev/null
@@ -1,285 +0,0 @@
-//
-// KeyInfoX509Data.cs - KeyInfoX509Data implementation for XML Signature
-//
-// Authors:
-//	Sebastien Pouliot  <sebastien@ximian.com>
-//	Atsushi Enomoto (atsushi@ximian.com)
-//      Tim Coleman (tim@timcoleman.com)
-//
-// (C) 2002, 2003 Motus Technologies Inc. (http://www.motus.com)
-// Copyright (C) Tim Coleman, 2004
-// Copyright (C) 2004-2005 Novell, Inc (http://www.novell.com)
-//
-// Permission is hereby granted, free of charge, to any person obtaining
-// a copy of this software and associated documentation files (the
-// "Software"), to deal in the Software without restriction, including
-// without limitation the rights to use, copy, modify, merge, publish,
-// distribute, sublicense, and/or sell copies of the Software, and to
-// permit persons to whom the Software is furnished to do so, subject to
-// the following conditions:
-// 
-// The above copyright notice and this permission notice shall be
-// included in all copies or substantial portions of the Software.
-// 
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
-// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
-// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
-// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
-// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
-// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
-// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-//
-
-using System.Collections;
-using System.Runtime.InteropServices;
-using System.Security.Cryptography.X509Certificates;
-using System.Xml;
-
-namespace System.Security.Cryptography.Xml {
-
-	public class KeyInfoX509Data : KeyInfoClause {
-
-		private byte[] x509crl;
-		private ArrayList IssuerSerialList;
-		private ArrayList SubjectKeyIdList;
-		private ArrayList SubjectNameList;
-		private ArrayList X509CertificateList;
-
-		public KeyInfoX509Data () 
-		{
-		}
-
-		public KeyInfoX509Data (byte[] rgbCert)
-		{
-			AddCertificate (new X509Certificate (rgbCert));
-		}
-
-		public KeyInfoX509Data (X509Certificate cert)
-		{
-			AddCertificate (cert);
-		}
-
-#if SECURITY_DEP
-		public KeyInfoX509Data (X509Certificate cert, X509IncludeOption includeOption)
-		{
-			if (cert == null)
-				throw new ArgumentNullException ("cert");
-
-			switch (includeOption) {
-			case X509IncludeOption.None:
-			case X509IncludeOption.EndCertOnly:
-				AddCertificate (cert);
-				break;
-			case X509IncludeOption.ExcludeRoot:
-				AddCertificatesChainFrom (cert, false);
-				break;
-			case X509IncludeOption.WholeChain:
-				AddCertificatesChainFrom (cert, true);
-				break;
-			}
-		}
-
-		// this gets complicated because we must:
-		// 1. build the chain using a X509Certificate2 class;
-		// 2. test for root using the Mono.Security.X509.X509Certificate class;
-		// 3. add the certificates as X509Certificate instances;
-		private void AddCertificatesChainFrom (X509Certificate cert, bool root)
-		{
-			X509Chain chain = new X509Chain ();
-			chain.Build (new X509Certificate2 (cert));
-			foreach (X509ChainElement ce in chain.ChainElements) {
-				byte[] rawdata = ce.Certificate.RawData;
-				if (!root) {
-					// exclude root
-					Mono.Security.X509.X509Certificate mx = new Mono.Security.X509.X509Certificate (rawdata);
-					if (mx.IsSelfSigned)
-						rawdata = null;
-				}
-
-				if (rawdata != null)
-					AddCertificate (new X509Certificate (rawdata));
-			}
-		}
-#endif
-
-		public ArrayList Certificates {
-			get { return X509CertificateList; }
-		}
-
-		public byte[] CRL {
-			get { return x509crl; }
-			set { x509crl = value; }
-		}
-
-		public ArrayList IssuerSerials {
-			get { return IssuerSerialList; }
-		}
-
-		public ArrayList SubjectKeyIds {
-			get { return SubjectKeyIdList; }
-		}
-
-		public ArrayList SubjectNames {
-			get { return SubjectNameList; }
-		}
-
-		public void AddCertificate (X509Certificate certificate) 
-		{
-			if (certificate == null)
-				throw new ArgumentNullException ("certificate");
-			if (X509CertificateList == null)
-				X509CertificateList = new ArrayList ();
-			X509CertificateList.Add (certificate);
-		}
-
-		public void AddIssuerSerial (string issuerName, string serialNumber) 
-		{
-			if (issuerName == null)
-				throw new ArgumentException ("issuerName");
-			if (IssuerSerialList == null)
-				IssuerSerialList = new ArrayList ();
-
-			X509IssuerSerial xis = new X509IssuerSerial (issuerName, serialNumber);
-			IssuerSerialList.Add (xis);
-		}
-
-		public void AddSubjectKeyId (byte[] subjectKeyId) 
-		{
-			if (SubjectKeyIdList == null)
-				SubjectKeyIdList = new ArrayList ();
-
-			SubjectKeyIdList.Add (subjectKeyId);
-		}
-
-		[ComVisible (false)]
-		public void AddSubjectKeyId (string subjectKeyId)
-		{
-			if (SubjectKeyIdList == null)
-				SubjectKeyIdList = new ArrayList ();
-
-			byte[] id = null;
-			if (subjectKeyId != null)
-				id = Convert.FromBase64String (subjectKeyId);
-			SubjectKeyIdList.Add (id);
-		}
-
-		public void AddSubjectName (string subjectName) 
-		{
-			if (SubjectNameList == null)
-				SubjectNameList = new ArrayList ();
-
-			SubjectNameList.Add (subjectName);
-		}
-
-		public override XmlElement GetXml () 
-		{
-			XmlDocument document = new XmlDocument ();
-			XmlElement xel = document.CreateElement (XmlSignature.ElementNames.X509Data, XmlSignature.NamespaceURI);
-			// FIXME: hack to match MS implementation
-			xel.SetAttribute ("xmlns", XmlSignature.NamespaceURI);
-			// <X509IssuerSerial>
-			if ((IssuerSerialList != null) && (IssuerSerialList.Count > 0)) {
-				foreach (X509IssuerSerial iser in IssuerSerialList) {
-					XmlElement isl = document.CreateElement (XmlSignature.ElementNames.X509IssuerSerial, XmlSignature.NamespaceURI);
-					XmlElement xin = document.CreateElement (XmlSignature.ElementNames.X509IssuerName, XmlSignature.NamespaceURI);
-					xin.InnerText = iser.IssuerName;
-					isl.AppendChild (xin);
- 					XmlElement xsn = document.CreateElement (XmlSignature.ElementNames.X509SerialNumber, XmlSignature.NamespaceURI);
-					xsn.InnerText = iser.SerialNumber;
-					isl.AppendChild (xsn);
-					xel.AppendChild (isl);
-				}
-			}
-			// <X509SKI>
-			if ((SubjectKeyIdList != null) && (SubjectKeyIdList.Count > 0)) {
-				foreach (byte[] skid in SubjectKeyIdList) {
-					XmlElement ski = document.CreateElement (XmlSignature.ElementNames.X509SKI, XmlSignature.NamespaceURI);
-					ski.InnerText = Convert.ToBase64String (skid);
-					xel.AppendChild (ski);
-				}
-			}
-			// <X509SubjectName>
-			if ((SubjectNameList != null) && (SubjectNameList.Count > 0)) {
-				foreach (string subject in SubjectNameList) {
-					XmlElement sn = document.CreateElement (XmlSignature.ElementNames.X509SubjectName, XmlSignature.NamespaceURI);
-					sn.InnerText = subject;
-					xel.AppendChild (sn);
-				}
-			}
-			// <X509Certificate>
-			if ((X509CertificateList != null) && (X509CertificateList.Count > 0)) {
-				foreach (X509Certificate x509 in X509CertificateList) {
-					XmlElement cert = document.CreateElement (XmlSignature.ElementNames.X509Certificate, XmlSignature.NamespaceURI);
-					cert.InnerText = Convert.ToBase64String (x509.GetRawCertData ());
-					xel.AppendChild (cert);
-				}
-			}
-			// only one <X509CRL> 
-			if (x509crl != null) {
-				XmlElement crl = document.CreateElement (XmlSignature.ElementNames.X509CRL, XmlSignature.NamespaceURI);
-				crl.InnerText = Convert.ToBase64String (x509crl);
-				xel.AppendChild (crl);
-			}
-			return xel;
-		}
-
-		public override void LoadXml (XmlElement element) 
-		{
-			if (element == null)
-				throw new ArgumentNullException ("element");
-
-			if (IssuerSerialList != null)
-				IssuerSerialList.Clear ();
-			if (SubjectKeyIdList != null)
-				SubjectKeyIdList.Clear ();
-			if (SubjectNameList != null)
-				SubjectNameList.Clear ();
-			if (X509CertificateList != null)
-				X509CertificateList.Clear ();
-			x509crl = null;
-
-			if ((element.LocalName != XmlSignature.ElementNames.X509Data) || (element.NamespaceURI != XmlSignature.NamespaceURI))
-				throw new CryptographicException ("element");
-
-			XmlElement [] xnl = null;
-			// <X509IssuerSerial>
-			xnl = XmlSignature.GetChildElements (element, XmlSignature.ElementNames.X509IssuerSerial);
-			if (xnl != null) {
-				for (int i=0; i < xnl.Length; i++) {
-					XmlElement xel = (XmlElement) xnl[i];
-					XmlElement issuer = XmlSignature.GetChildElement (xel, XmlSignature.ElementNames.X509IssuerName, XmlSignature.NamespaceURI);
-					XmlElement serial = XmlSignature.GetChildElement (xel, XmlSignature.ElementNames.X509SerialNumber, XmlSignature.NamespaceURI);
-					AddIssuerSerial (issuer.InnerText, serial.InnerText);
-				}
-			}
-			// <X509SKI>
-			xnl = XmlSignature.GetChildElements (element, XmlSignature.ElementNames.X509SKI);
-			if (xnl != null) {
-				for (int i=0; i < xnl.Length; i++) {
-					byte[] skid = Convert.FromBase64String (xnl[i].InnerXml);
-					AddSubjectKeyId (skid);
-				}
-			}
-			// <X509SubjectName>
-			xnl = XmlSignature.GetChildElements (element, XmlSignature.ElementNames.X509SubjectName);
-			if (xnl != null) {
-				for (int i=0; i < xnl.Length; i++) {
-					AddSubjectName (xnl[i].InnerXml);
-				}
-			}
-			// <X509Certificate>
-			xnl = XmlSignature.GetChildElements (element, XmlSignature.ElementNames.X509Certificate);
-			if (xnl != null) {
-				for (int i=0; i < xnl.Length; i++) {
-					byte[] cert = Convert.FromBase64String (xnl[i].InnerXml);
-					AddCertificate (new X509Certificate (cert));
-				}
-			}
-			// only one <X509CRL> 
-			XmlElement x509el = XmlSignature.GetChildElement (element, XmlSignature.ElementNames.X509CRL, XmlSignature.NamespaceURI);
-			if (x509el != null) {
-				x509crl = Convert.FromBase64String (x509el.InnerXml);
-			}
-		}
-	}
-}
diff --git a/mcs/class/System.Security/System.Security.Cryptography.Xml/Manifest.cs b/mcs/class/System.Security/System.Security.Cryptography.Xml/Manifest.cs
deleted file mode 100644
index d52ea001d43..00000000000
--- a/mcs/class/System.Security/System.Security.Cryptography.Xml/Manifest.cs
+++ /dev/null
@@ -1,119 +0,0 @@
-//
-// Manifest.cs - Manifest implementation for XML Signature
-//
-// Author:
-//	Sebastien Pouliot  <sebastien@ximian.com>
-//
-// (C) 2004 Novell (http://www.novell.com)
-//
-
-//
-// Permission is hereby granted, free of charge, to any person obtaining
-// a copy of this software and associated documentation files (the
-// "Software"), to deal in the Software without restriction, including
-// without limitation the rights to use, copy, modify, merge, publish,
-// distribute, sublicense, and/or sell copies of the Software, and to
-// permit persons to whom the Software is furnished to do so, subject to
-// the following conditions:
-// 
-// The above copyright notice and this permission notice shall be
-// included in all copies or substantial portions of the Software.
-// 
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
-// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
-// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
-// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
-// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
-// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
-// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-//
-
-using System.Collections;
-using System.Xml;
-
-namespace System.Security.Cryptography.Xml { 
-
-	internal class Manifest {
-
-		private ArrayList references;
-		private string id;
-		private XmlElement element;
-
-		public Manifest ()
-		{
-			references = new ArrayList ();
-		}
-
-		public Manifest (XmlElement xel) : this ()
-		{
-			LoadXml (xel);
-		}
-
-		public string Id {
-			get { return id; }
-			set {
-				element = null;
-				id = value;
-			}
-		}
-
-		public ArrayList References {
-			get { return references; }
-		}
-
-		public void AddReference (Reference reference) 
-		{
-			references.Add (reference);
-		}
-
-		public XmlElement GetXml () 
-		{
-			if (element != null)
-				return element;
-
-			XmlDocument document = new XmlDocument ();
-			XmlElement xel = document.CreateElement (XmlSignature.ElementNames.SignedInfo, XmlSignature.NamespaceURI);
-			if (id != null)
-				xel.SetAttribute (XmlSignature.AttributeNames.Id, id);
-
-			// we add References afterward so we don't end up with extraneous
-			// xmlns="..." in each reference elements.
-			foreach (Reference r in references) {
-				XmlNode xn = r.GetXml ();
-				XmlNode newNode = document.ImportNode (xn, true);
-				xel.AppendChild (newNode);
-			}
-
-			return xel;
-		}
-
-		private string GetAttribute (XmlElement xel, string attribute) 
-		{
-			XmlAttribute xa = xel.Attributes [attribute];
-			return ((xa != null) ? xa.InnerText : null);
-		}
-
-		public void LoadXml (XmlElement value) 
-		{
-			if (value == null)
-				throw new ArgumentNullException ("value");
-
-			if ((value.LocalName != XmlSignature.ElementNames.Manifest) || (value.NamespaceURI != XmlSignature.NamespaceURI))
-				throw new CryptographicException ();
-
-			id = GetAttribute (value, XmlSignature.AttributeNames.Id);
-
-			for (int i = 0; i < value.ChildNodes.Count; i++) {
-				XmlNode n = value.ChildNodes [i];
-				if (n.NodeType == XmlNodeType.Element &&
-					n.LocalName == XmlSignature.ElementNames.Reference &&
-					n.NamespaceURI == XmlSignature.NamespaceURI) {
-					Reference r = new Reference ();
-					r.LoadXml ((XmlElement) n);
-					AddReference (r);
-				}
-			}
-			element = value;
-		}
-	}
-}
diff --git a/mcs/class/System.Security/System.Security.Cryptography.Xml/Signature.cs b/mcs/class/System.Security/System.Security.Cryptography.Xml/Signature.cs
deleted file mode 100644
index 49e9d3ad991..00000000000
--- a/mcs/class/System.Security/System.Security.Cryptography.Xml/Signature.cs
+++ /dev/null
@@ -1,221 +0,0 @@
-//
-// Signature.cs - Signature implementation for XML Signature
-//
-// Author:
-//	Sebastien Pouliot (spouliot@motus.com)
-//      Tim Coleman (tim@timcoleman.com)
-//
-// (C) 2002, 2003 Motus Technologies Inc. (http://www.motus.com)
-// Copyright (C) Tim Coleman, 2004
-//
-
-//
-// Permission is hereby granted, free of charge, to any person obtaining
-// a copy of this software and associated documentation files (the
-// "Software"), to deal in the Software without restriction, including
-// without limitation the rights to use, copy, modify, merge, publish,
-// distribute, sublicense, and/or sell copies of the Software, and to
-// permit persons to whom the Software is furnished to do so, subject to
-// the following conditions:
-// 
-// The above copyright notice and this permission notice shall be
-// included in all copies or substantial portions of the Software.
-// 
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
-// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
-// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
-// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
-// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
-// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
-// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-//
-
-using System.Collections;
-using System.Security.Cryptography;
-using System.Xml;
-
-namespace System.Security.Cryptography.Xml {
-
-	public class Signature {
-		static XmlNamespaceManager dsigNsmgr;
-		
-		static Signature ()
-		{
-			dsigNsmgr = new XmlNamespaceManager (new NameTable ());
-			dsigNsmgr.AddNamespace ("xd", XmlSignature.NamespaceURI);
-		}
-
-		private ArrayList list;
-		private SignedInfo info;
-		private KeyInfo key;
-		private string id;
-		private byte[] signature;
-		private XmlElement element;
-
-		public Signature () 
-		{
-			list = new ArrayList ();
-		}
-
-		public string Id {
-			get { return id; }
-			set {
-				element = null;
-				id = value;
-			}
-		}
-
-		public KeyInfo KeyInfo {
-			get { return key; }
-			set {
-				element = null;
-				key = value;
-			}
-		}
-
-		public IList ObjectList {
-			get { return list; }
-			set { list = ArrayList.Adapter (value); }
-		}
-
-		public byte[] SignatureValue {
-			get { return signature; }
-			set {
-				element = null;
-				signature = value;
-			}
-		}
-
-		public SignedInfo SignedInfo {
-			get { return info; }
-			set {
-				element = null;
-				info = value;
-			}
-		}
-
-		public void AddObject (DataObject dataObject) 
-		{
-			list.Add (dataObject);
-		}
-
-		public XmlElement GetXml () 
-		{
-			return GetXml (null);
-		}
-
-		internal XmlElement GetXml (XmlDocument document)
-		{
-			if (element != null)
-				return element;
-
-			if (info == null)
-				throw new CryptographicException ("SignedInfo");
-			if (signature == null)
-				throw new CryptographicException ("SignatureValue");
-
-			if (document == null)
-				document = new XmlDocument ();
-
-			XmlElement xel = document.CreateElement (XmlSignature.ElementNames.Signature, XmlSignature.NamespaceURI);
-			if (id != null)
-				xel.SetAttribute (XmlSignature.AttributeNames.Id, id);
-
-			XmlNode xn = info.GetXml ();
-			XmlNode newNode = document.ImportNode (xn, true);
-			xel.AppendChild (newNode);
-
-			if (signature != null) {
-				XmlElement sv = document.CreateElement (XmlSignature.ElementNames.SignatureValue, XmlSignature.NamespaceURI);
-				sv.InnerText = Convert.ToBase64String (signature);
-				xel.AppendChild (sv);
-			}
-
-			if (key != null) {
-				xn = key.GetXml ();
-				newNode = document.ImportNode (xn, true);
-				xel.AppendChild (newNode);
-			}
-
-			if (list.Count > 0) {
-				foreach (DataObject obj in list) {
-					xn = obj.GetXml ();
-					newNode = document.ImportNode (xn, true);
-					xel.AppendChild (newNode);
-				}
-			}
-
-			return xel;
-		}
-
-		private string GetAttribute (XmlElement xel, string attribute) 
-		{
-			XmlAttribute xa = xel.Attributes [attribute];
-			return ((xa != null) ? xa.InnerText : null);
-		}
-
-		public void LoadXml (XmlElement value) 
-		{
-			if (value == null)
-				throw new ArgumentNullException ("value");
-
-			if ((value.LocalName == XmlSignature.ElementNames.Signature) && (value.NamespaceURI == XmlSignature.NamespaceURI)) {
-				id = GetAttribute (value, XmlSignature.AttributeNames.Id);
-
-				// LAMESPEC: This library is totally useless against eXtensibly Marked-up document.
-				int i = NextElementPos (value.ChildNodes, 0, XmlSignature.ElementNames.SignedInfo, XmlSignature.NamespaceURI, true);
-				XmlElement sinfo = (XmlElement) value.ChildNodes [i];
-				info = new SignedInfo ();
-				info.LoadXml (sinfo);
-
-				i = NextElementPos (value.ChildNodes, ++i, XmlSignature.ElementNames.SignatureValue, XmlSignature.NamespaceURI, true);
-				XmlElement sigValue = (XmlElement) value.ChildNodes [i];
-				signature = Convert.FromBase64String (sigValue.InnerText);
-
-				// signature isn't required: <element ref="ds:KeyInfo" minOccurs="0"/> 
-				i = NextElementPos (value.ChildNodes, ++i, XmlSignature.ElementNames.KeyInfo, XmlSignature.NamespaceURI, false);
-				if (i > 0) {
-					XmlElement kinfo = (XmlElement) value.ChildNodes [i];
-					key = new KeyInfo ();
-					key.LoadXml (kinfo);
-				}
-
-				XmlNodeList xnl = value.SelectNodes ("xd:Object", dsigNsmgr);
-				foreach (XmlElement xn in xnl) {
-					DataObject obj = new DataObject ();
-					obj.LoadXml (xn);
-					AddObject (obj);
-				}
-			}
-			else
-				throw new CryptographicException ("Malformed element: Signature.");
-
-			// if invalid
-			if (info == null)
-				throw new CryptographicException ("SignedInfo");
-			if (signature == null)
-				throw new CryptographicException ("SignatureValue");
-		}
-
-		private int NextElementPos (XmlNodeList nl, int pos, string name, string ns, bool required)
-		{
-			while (pos < nl.Count) {
-				if (nl [pos].NodeType == XmlNodeType.Element) {
-					if (nl [pos].LocalName != name || nl [pos].NamespaceURI != ns) {
-						if (required)
-							throw new CryptographicException ("Malformed element " + name);
-						else
-							return -2;
-					}
-					else
-						return pos;
-				}
-				else
-					pos++;
-			}
-			if (required)
-				throw new CryptographicException ("Malformed element " + name);
-			return -1;
-		}
-	}
-}
diff --git a/mcs/class/System.Security/System.Security.Cryptography.Xml/SignedInfo.cs b/mcs/class/System.Security/System.Security.Cryptography.Xml/SignedInfo.cs
deleted file mode 100644
index f9d6d9f0048..00000000000
--- a/mcs/class/System.Security/System.Security.Cryptography.Xml/SignedInfo.cs
+++ /dev/null
@@ -1,219 +0,0 @@
-//
-// SignedInfo.cs - SignedInfo implementation for XML Signature
-//
-// Author:
-//	Sebastien Pouliot  <sebastien@ximian.com>
-//      Tim Coleman (tim@timcoleman.com)
-//
-// (C) 2002, 2003 Motus Technologies Inc. (http://www.motus.com)
-// Copyright (C) Tim Coleman, 2004
-// Copyright (C) 2004-2005 Novell, Inc (http://www.novell.com)
-//
-// Permission is hereby granted, free of charge, to any person obtaining
-// a copy of this software and associated documentation files (the
-// "Software"), to deal in the Software without restriction, including
-// without limitation the rights to use, copy, modify, merge, publish,
-// distribute, sublicense, and/or sell copies of the Software, and to
-// permit persons to whom the Software is furnished to do so, subject to
-// the following conditions:
-// 
-// The above copyright notice and this permission notice shall be
-// included in all copies or substantial portions of the Software.
-// 
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
-// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
-// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
-// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
-// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
-// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
-// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-//
-
-using System.Collections;
-using System.Runtime.InteropServices;
-using System.Xml;
-
-namespace System.Security.Cryptography.Xml { 
-
-	public class SignedInfo : ICollection, IEnumerable {
-
-		private ArrayList references;
-		private string c14nMethod;
-		private string id;
-		private string signatureMethod;
-		private string signatureLength;
-		private XmlElement element;
-
-		public SignedInfo() 
-		{
-			references = new ArrayList ();
-			c14nMethod = "http://www.w3.org/TR/2001/REC-xml-c14n-20010315";
-		}
-
-		public string CanonicalizationMethod {
-			get { return c14nMethod; }
-			set {
-				c14nMethod = value;
-				element = null;
-			}
-		}
-
-		[ComVisible (false)]
-		[MonoTODO]
-		public Transform CanonicalizationMethodObject {
-			get { throw new NotImplementedException (); }
-		}
-
-		// documented as not supported (and throwing exception)
-		public int Count {
-			get { throw new NotSupportedException (); }
-		}
-
-		public string Id {
-			get { return id; }
-			set {
-				element = null;
-				id = value;
-			}
-		}
-
-		// documented as not supported (and throwing exception)
-		public bool IsReadOnly {
-			get { throw new NotSupportedException (); }
-		}
-
-		// documented as not supported (and throwing exception)
-		public bool IsSynchronized {
-			get { throw new NotSupportedException (); }
-		}
-
-		// Manipulating this array never affects GetXml() when 
-		// LoadXml() was used. 
-		// (Actually, there is no way to detect modification.)
-		public ArrayList References {
-			get { return references; }
-		}
-
-		public string SignatureLength {
-			get { return signatureLength; }
-			set {
-				element = null;
-				signatureLength = value;
-			}
-		}
-
-		public string SignatureMethod {
-			get { return signatureMethod; }
-			set {
-				element = null;
-				signatureMethod = value;
-			}
-		}
-
-		// documented as not supported (and throwing exception)
-		public object SyncRoot {
-			get { throw new NotSupportedException (); }
-		}
-
-		public void AddReference (Reference reference) 
-		{
-			references.Add (reference);
-		}
-
-		// documented as not supported (and throwing exception)
-		public void CopyTo (Array array, int index) 
-		{
-			throw new NotSupportedException ();
-		}
-
-		public IEnumerator GetEnumerator () 
-		{
-			return references.GetEnumerator ();
-		}
-
-		public XmlElement GetXml ()
-		{
-			if (element != null)
-				return element;
-
-			if (signatureMethod == null)
-				throw new CryptographicException ("SignatureMethod");
-			if (references.Count == 0)
-				throw new CryptographicException ("References empty");
-
-			XmlDocument document = new XmlDocument ();
-			XmlElement xel = document.CreateElement (XmlSignature.ElementNames.SignedInfo, XmlSignature.NamespaceURI);
-			if (id != null)
-				xel.SetAttribute (XmlSignature.AttributeNames.Id, id);
-
-			if (c14nMethod != null) {
-				XmlElement c14n = document.CreateElement (XmlSignature.ElementNames.CanonicalizationMethod, XmlSignature.NamespaceURI);
-				c14n.SetAttribute (XmlSignature.AttributeNames.Algorithm, c14nMethod);
-				xel.AppendChild (c14n);
-			}
-			if (signatureMethod != null) {
-				XmlElement sm = document.CreateElement (XmlSignature.ElementNames.SignatureMethod, XmlSignature.NamespaceURI);
-				sm.SetAttribute (XmlSignature.AttributeNames.Algorithm, signatureMethod);
-				if (signatureLength != null) {
-					XmlElement hmac = document.CreateElement (XmlSignature.ElementNames.HMACOutputLength, XmlSignature.NamespaceURI);
-					hmac.InnerText = signatureLength;
-					sm.AppendChild (hmac);
-				}
-				xel.AppendChild (sm);
-			}
-
-			// This check is only done when element is created here.
-			if (references.Count == 0)
-				throw new CryptographicException ("At least one Reference element is required in SignedInfo.");
-
-			// we add References afterward so we don't end up with extraneous
-			// xmlns="..." in each reference elements.
-			foreach (Reference r in references) {
-				XmlNode xn = r.GetXml ();
-				XmlNode newNode = document.ImportNode (xn, true);
-				xel.AppendChild (newNode);
-			}
-
-			return xel;
-		}
-
-		private string GetAttribute (XmlElement xel, string attribute) 
-		{
-			XmlAttribute xa = xel.Attributes [attribute];
-			return ((xa != null) ? xa.InnerText : null);
-		}
-
-		public void LoadXml (XmlElement value) 
-		{
-			if (value == null)
-				throw new ArgumentNullException ("value");
-
-			if ((value.LocalName != XmlSignature.ElementNames.SignedInfo) || (value.NamespaceURI != XmlSignature.NamespaceURI))
-				throw new CryptographicException ();
-
-			id = GetAttribute (value, XmlSignature.AttributeNames.Id);
-			c14nMethod = XmlSignature.GetAttributeFromElement (value, XmlSignature.AttributeNames.Algorithm, XmlSignature.ElementNames.CanonicalizationMethod);
-
-			XmlElement sm = XmlSignature.GetChildElement (value, XmlSignature.ElementNames.SignatureMethod, XmlSignature.NamespaceURI);
-			if (sm != null) {
-				signatureMethod = sm.GetAttribute (XmlSignature.AttributeNames.Algorithm);
-				XmlElement length = XmlSignature.GetChildElement (sm, XmlSignature.ElementNames.HMACOutputLength, XmlSignature.NamespaceURI);
-				if (length != null) {
-					signatureLength = length.InnerText;
-				}
-			}
-
-			for (int i = 0; i < value.ChildNodes.Count; i++) {
-				XmlNode n = value.ChildNodes [i];
-				if (n.NodeType == XmlNodeType.Element &&
-					n.LocalName == XmlSignature.ElementNames.Reference &&
-					n.NamespaceURI == XmlSignature.NamespaceURI) {
-					Reference r = new Reference ();
-					r.LoadXml ((XmlElement) n);
-					AddReference (r);
-				}
-			}
-			element = value;
-		}
-	}
-}
diff --git a/mcs/class/System.Security/System.Security.Cryptography.Xml/SignedXml.cs b/mcs/class/System.Security/System.Security.Cryptography.Xml/SignedXml.cs
index 958f9138365..15e50ca5fcf 100644
--- a/mcs/class/System.Security/System.Security.Cryptography.Xml/SignedXml.cs
+++ b/mcs/class/System.Security/System.Security.Cryptography.Xml/SignedXml.cs
@@ -1,48 +1,57 @@
-//
-// SignedXml.cs - SignedXml implementation for XML Signature
-//
-// Author:
-//	Sebastien Pouliot  <sebastien@ximian.com>
-//	Atsushi Enomoto <atsushi@ximian.com>
-//      Tim Coleman <tim@timcoleman.com>
-//
-// (C) 2002, 2003 Motus Technologies Inc. (http://www.motus.com)
-// Copyright (C) Tim Coleman, 2004
-// Copyright (C) 2004-2005 Novell, Inc (http://www.novell.com)
-//
-// Permission is hereby granted, free of charge, to any person obtaining
-// a copy of this software and associated documentation files (the
-// "Software"), to deal in the Software without restriction, including
-// without limitation the rights to use, copy, modify, merge, publish,
-// distribute, sublicense, and/or sell copies of the Software, and to
-// permit persons to whom the Software is furnished to do so, subject to
-// the following conditions:
-// 
-// The above copyright notice and this permission notice shall be
-// included in all copies or substantial portions of the Software.
-// 
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
-// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
-// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
-// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
-// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
-// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
-// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-//
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
 
 using System.Collections;
-using System.IO;
+using System.Collections.Generic;
+using System.Collections.ObjectModel;
+using System.Runtime.CompilerServices;
 using System.Runtime.InteropServices;
-using System.Security.Cryptography;
-using System.Security.Policy;
-using System.Net;
-using System.Text;
-using System.Xml;
 using System.Security.Cryptography.X509Certificates;
+using System.Xml;
 
 namespace System.Security.Cryptography.Xml {
-
 	public class SignedXml {
+		/// <internalonly />
+		protected Signature m_signature;
+		/// <internalonly />
+		protected string m_strSigningKeyName;
+
+		private AsymmetricAlgorithm _signingKey;
+		private XmlDocument _containingDocument;
+		private IEnumerator _keyInfoEnum;
+		private X509Certificate2Collection _x509Collection;
+		private IEnumerator _x509Enum;
+
+		private bool[] _refProcessed;
+		private int[] _refLevelCache;
+
+		internal XmlResolver _xmlResolver;
+		internal XmlElement _context;
+		private bool _bResolverSet;
+
+		private Func<SignedXml, bool> _signatureFormatValidator = DefaultSignatureFormatValidator;
+		private Collection<string> _safeCanonicalizationMethods;
+
+		// Built in canonicalization algorithm URIs
+		private static IList<string> s_knownCanonicalizationMethods;
+		// Built in transform algorithm URIs (excluding canonicalization URIs)
+		private static IList<string> s_defaultSafeTransformMethods;
+
+		// additional HMAC Url identifiers
+		private const string XmlDsigMoreHMACMD5Url = "http://www.w3.org/2001/04/xmldsig-more#hmac-md5";
+		private const string XmlDsigMoreHMACSHA256Url = "http://www.w3.org/2001/04/xmldsig-more#hmac-sha256";
+		private const string XmlDsigMoreHMACSHA384Url = "http://www.w3.org/2001/04/xmldsig-more#hmac-sha384";
+		private const string XmlDsigMoreHMACSHA512Url = "http://www.w3.org/2001/04/xmldsig-more#hmac-sha512";
+		private const string XmlDsigMoreHMACRIPEMD160Url = "http://www.w3.org/2001/04/xmldsig-more#hmac-ripemd160";
+
+		// defines the XML encryption processing rules
+		private EncryptedXml _exml;
+
+		//
+		// public constant Url identifiers most frequently used within the XML Signature classes
+		//
+
 		public const string XmlDsigNamespaceUrl = "http://www.w3.org/2000/09/xmldsig#";
 		public const string XmlDsigMinimalCanonicalizationUrl = "http://www.w3.org/2000/09/xmldsig#minimal";
 		public const string XmlDsigCanonicalizationUrl = XmlDsigC14NTransformUrl;
@@ -63,6 +72,9 @@ namespace System.Security.Cryptography.Xml {
 		public const string XmlDsigSHA512Url = "http://www.w3.org/2001/04/xmlenc#sha512";
 		public const string XmlDsigRSASHA512Url = "http://www.w3.org/2001/04/xmldsig-more#rsa-sha512";
 
+		internal static readonly string XmlDsigDigestDefault = XmlDsigSHA256Url;
+		internal static readonly string XmlDsigRSADefault = XmlDsigRSASHA256Url;
+
 		public const string XmlDsigC14NTransformUrl = "http://www.w3.org/TR/2001/REC-xml-c14n-20010315";
 		public const string XmlDsigC14NWithCommentsTransformUrl = "http://www.w3.org/TR/2001/REC-xml-c14n-20010315#WithComments";
 		public const string XmlDsigExcC14NTransformUrl = "http://www.w3.org/2001/10/xml-exc-c14n#";
@@ -74,91 +86,50 @@ namespace System.Security.Cryptography.Xml {
 		public const string XmlDecryptionTransformUrl = "http://www.w3.org/2002/07/decrypt#XML";
 		public const string XmlLicenseTransformUrl = "urn:mpeg:mpeg21:2003:01-REL-R-NS:licenseTransform";
 
-		private EncryptedXml encryptedXml;
-
-		protected Signature m_signature;
-		private AsymmetricAlgorithm key;
-		protected string m_strSigningKeyName;
-		private XmlDocument envdoc;
-		private IEnumerator pkEnumerator;
-		private XmlElement signatureElement;
-		private Hashtable hashes;
-		// FIXME: enable it after CAS implementation
-		internal XmlResolver _xmlResolver = new XmlUrlResolver ();
-		private bool _bResolverSet = true;
-		internal XmlElement _context;
-		private ArrayList manifests;
-		private IEnumerator _x509Enumerator;
-
-		private static readonly char [] whitespaceChars = new char [] {' ', '\r', '\n', '\t'};
+		//
+		// public constructors
+		//
 
 		public SignedXml () 
 		{
-			m_signature = new Signature ();
-			m_signature.SignedInfo = new SignedInfo ();
-			hashes = new Hashtable (2); // 98% SHA1 for now
-			_context = null;
+			Initialize (null);
 		}
 
-		public SignedXml (XmlDocument document) : this ()
+		public SignedXml (XmlDocument document)
 		{
 			if (document == null)
-				throw new ArgumentNullException ("document");
-			envdoc = document;
-			_context = document.DocumentElement;
+				throw new ArgumentNullException (nameof (document));
+			
+			Initialize (document.DocumentElement);
 		}
 
-		public SignedXml (XmlElement elem) : this ()
+		public SignedXml (XmlElement elem)
 		{
 			if (elem == null)
-				throw new ArgumentNullException ("elem");
-			envdoc = new XmlDocument ();
-			_context = elem;
-			envdoc.LoadXml (elem.OuterXml);
-		}
-
-		[ComVisible (false)]
-		public EncryptedXml EncryptedXml {
-			get { return encryptedXml; }
-			set { encryptedXml = value; }
-		}
-
-		public KeyInfo KeyInfo {
-			get {
-				if (m_signature.KeyInfo == null)
-					m_signature.KeyInfo = new KeyInfo ();
-				return m_signature.KeyInfo;
-			}
-			set { m_signature.KeyInfo = value; }
-		}
-
-		public Signature Signature {
-			get { return m_signature; }
-		}
-
-		public string SignatureLength {
-			get { return m_signature.SignedInfo.SignatureLength; }
+				throw new ArgumentNullException (nameof (elem));
+			
+			Initialize (elem);
 		}
 
-		public string SignatureMethod {
-			get { return m_signature.SignedInfo.SignatureMethod; }
-		}
+		private void Initialize (XmlElement element)
+		{
+			_containingDocument = (element == null ? null : element.OwnerDocument);
+			_context = element;
+			m_signature = new Signature ();
+			m_signature.SignedXml = this;
+			m_signature.SignedInfo = new SignedInfo ();
+			_signingKey = null;
 
-		public byte[] SignatureValue {
-			get { return m_signature.SignatureValue; }
+			_safeCanonicalizationMethods = new Collection<string> (KnownCanonicalizationMethods);
 		}
 
-		public SignedInfo SignedInfo {
-			get { return m_signature.SignedInfo; }
-		}
+		//
+		// public properties
+		//
 
-		public AsymmetricAlgorithm SigningKey {
-			get { return key; }
-			set { key = value; }
-		}
-
-		// NOTE: CryptoAPI related ? documented as fx internal
-		public string SigningKeyName {
+		/// <internalonly />
+		public string SigningKeyName
+		{
 			get { return m_strSigningKeyName; }
 			set { m_strSigningKeyName = value; }
 		}
@@ -179,483 +150,221 @@ namespace System.Security.Cryptography.Xml {
 			get { return _bResolverSet; }
 		}
 
-		public void AddObject (DataObject dataObject) 
+		public Func<SignedXml, bool> SignatureFormatValidator
 		{
-			m_signature.AddObject (dataObject);
+			get { return _signatureFormatValidator; }
+			set { _signatureFormatValidator = value; }
 		}
 
-		public void AddReference (Reference reference) 
+		public Collection<string> SafeCanonicalizationMethods
 		{
-			if (reference == null)
-				throw new ArgumentNullException ("reference");
-			m_signature.SignedInfo.AddReference (reference);
+			get { return _safeCanonicalizationMethods; }
 		}
 
-		private Stream ApplyTransform (Transform t, XmlDocument input) 
+		public AsymmetricAlgorithm SigningKey
 		{
-			// These transformer modify input document, which should
-			// not affect to the input itself.
-			if (t is XmlDsigXPathTransform 
-				|| t is XmlDsigEnvelopedSignatureTransform
-				|| t is XmlDecryptionTransform
-			)
-				input = (XmlDocument) input.Clone ();
-
-			t.LoadInput (input);
-
-			if (t is XmlDsigEnvelopedSignatureTransform)
-				// It returns XmlDocument for XmlDocument input.
-				return CanonicalizeOutput (t.GetOutput ());
-
-			object obj = t.GetOutput ();
-			if (obj is Stream)
-				return (Stream) obj;
-			else if (obj is XmlDocument) {
-				MemoryStream ms = new MemoryStream ();
-				XmlTextWriter xtw = new XmlTextWriter (ms, Encoding.UTF8);
-				((XmlDocument) obj).WriteTo (xtw);
-
-				xtw.Flush ();
+			get { return _signingKey; }
+			set { _signingKey = value; }
+		}
 
-				// Rewind to the start of the stream
-				ms.Position = 0;
-				return ms;
-			}
-			else if (obj == null) {
-				throw new NotImplementedException ("This should not occur. Transform is " + t + ".");
-			}
-			else {
-				// e.g. XmlDsigXPathTransform returns XmlNodeList
-				return CanonicalizeOutput (obj);
+		public EncryptedXml EncryptedXml
+		{
+			get
+			{
+				if (_exml == null)
+					_exml = new EncryptedXml (_containingDocument); // default processing rules
+				
+				return _exml;
 			}
+
+			set { _exml = value; }
 		}
 
-		private Stream CanonicalizeOutput (object obj)
+		public Signature Signature
 		{
-			Transform c14n = GetC14NMethod ();
-			c14n.LoadInput (obj);
-			return (Stream) c14n.GetOutput ();
+			get { return m_signature; }
 		}
 
-		private XmlDocument GetManifest (Reference r) 
+		public SignedInfo SignedInfo
 		{
-			XmlDocument doc = new XmlDocument ();
-			doc.PreserveWhitespace = true;
-
-			if (r.Uri [0] == '#') {
-				// local manifest
-				if (signatureElement != null) {
-					XmlElement xel = GetIdElement (signatureElement.OwnerDocument, r.Uri.Substring (1));
-					if (xel == null)
-						throw new CryptographicException ("Manifest targeted by Reference was not found: " + r.Uri.Substring (1));
-					doc.AppendChild (doc.ImportNode (xel, true));
-					FixupNamespaceNodes (xel, doc.DocumentElement, false);
-				}
-			}
-			else if (_xmlResolver != null) {
-				// TODO: need testing
-				Stream s = (Stream) _xmlResolver.GetEntity (new Uri (r.Uri), null, typeof (Stream));
-				doc.Load (s);
-			}
-
-			if (doc.FirstChild != null) {
-				// keep a copy of the manifests to check their references later
-				if (manifests == null)
-					manifests = new ArrayList ();
-				manifests.Add (doc);
-
-				return doc;
-			}
-			return null;
+			get { return m_signature.SignedInfo; }
 		}
 
-		private void FixupNamespaceNodes (XmlElement src, XmlElement dst, bool ignoreDefault)
+		public string SignatureMethod
 		{
-			// add namespace nodes
-			foreach (XmlAttribute attr in src.SelectNodes ("namespace::*")) {
-				if (attr.LocalName == "xml")
-					continue;
-				if (ignoreDefault && attr.LocalName == "xmlns")
-					continue;
-				dst.SetAttributeNode (dst.OwnerDocument.ImportNode (attr, true) as XmlAttribute);
-			}
+			get { return m_signature.SignedInfo.SignatureMethod; }
 		}
 
-		private byte[] GetReferenceHash (Reference r, bool check_hmac) 
+		public string SignatureLength
 		{
-			Stream s = null;
-			XmlDocument doc = null;
-			if (r.Uri == String.Empty) {
-				doc = envdoc;
-			}
-			else if (r.Type == XmlSignature.Uri.Manifest) {
-				doc = GetManifest (r);
-			}
-			else {
-				doc = new XmlDocument ();
-				doc.PreserveWhitespace = true;
-				string objectName = null;
-
-				if (r.Uri.StartsWith ("#xpointer")) {
-					string uri = string.Join ("", r.Uri.Substring (9).Split (whitespaceChars));
-					if (uri.Length < 2 || uri [0] != '(' || uri [uri.Length - 1] != ')')
-						// FIXME: how to handle invalid xpointer?
-						uri = String.Empty;
-					else
-						uri = uri.Substring (1, uri.Length - 2);
-					if (uri == "/")
-						doc = envdoc;
-					else if (uri.Length > 6 && uri.StartsWith ("id(") && uri [uri.Length - 1] == ')')
-						// id('foo'), id("foo")
-						objectName = uri.Substring (4, uri.Length - 6);
-				}
-				else if (r.Uri [0] == '#') {
-					objectName = r.Uri.Substring (1);
-				}
-				else if (_xmlResolver != null) {
-					// TODO: test but doc says that Resolver = null -> no access
-					try {
-						// no way to know if valid without throwing an exception
-						Uri uri = new Uri (r.Uri);
-						s = (Stream) _xmlResolver.GetEntity (uri, null, typeof (Stream));
-					}
-					catch {
-						// may still be a local file (and maybe not xml)
-						s = File.OpenRead (r.Uri);
-					}
-				}
-				if (objectName != null) {
-					XmlElement found = null;
-					foreach (DataObject obj in m_signature.ObjectList) {
-						if (obj.Id == objectName) {
-							found = obj.GetXml ();
-							found.SetAttribute ("xmlns", SignedXml.XmlDsigNamespaceUrl);
-							doc.AppendChild (doc.ImportNode (found, true));
-							// FIXME: there should be theoretical justification of copying namespace declaration nodes this way.
-							foreach (XmlNode n in found.ChildNodes)
-								// Do not copy default namespace as it must be xmldsig namespace for "Object" element.
-								if (n.NodeType == XmlNodeType.Element)
-									FixupNamespaceNodes (n as XmlElement, doc.DocumentElement, true);
-							break;
-						}
-					}
-					if (found == null && envdoc != null) {
-						found = GetIdElement (envdoc, objectName);
-						if (found != null) {
-							doc.AppendChild (doc.ImportNode (found, true));
-							FixupNamespaceNodes (found, doc.DocumentElement, false);
-						}
-					}
-					if (found == null)
-						throw new CryptographicException (String.Format ("Malformed reference object: {0}", objectName));
-				}
-			}
-
-			if (r.TransformChain.Count > 0) {		
-				foreach (Transform t in r.TransformChain) {
-					if (s == null) {
-						s = ApplyTransform (t, doc);
-					}
-					else {
-						t.LoadInput (s);
-						object o = t.GetOutput ();
-						if (o is Stream)
-							s = (Stream) o;
-						else
-							s = CanonicalizeOutput (o);
-					}
-				}
-			}
-			else if (s == null) {
-				// we must not C14N references from outside the document
-				// e.g. non-xml documents
-				if (r.Uri [0] != '#') {
-					s = new MemoryStream ();
-					doc.Save (s);
-				}
-				else {
-					// apply default C14N transformation
-					s = ApplyTransform (new XmlDsigC14NTransform (), doc);
-				}
-			}
-			HashAlgorithm digest = GetHash (r.DigestMethod, check_hmac);
-			return (digest == null) ? null : digest.ComputeHash (s);
+			get { return m_signature.SignedInfo.SignatureLength; }
 		}
 
-		private void DigestReferences () 
+		public byte[] SignatureValue
 		{
-			// we must tell each reference which hash algorithm to use 
-			// before asking for the SignedInfo XML !
-			foreach (Reference r in m_signature.SignedInfo.References) {
-				// assume SHA-1 if nothing is specified
-				if (r.DigestMethod == null)
-					r.DigestMethod = XmlDsigSHA1Url;
-				r.DigestValue = GetReferenceHash (r, false);
-			}
+			get { return m_signature.SignatureValue; }
 		}
 
-		private Transform GetC14NMethod ()
+		public KeyInfo KeyInfo
 		{
-			Transform t = (Transform) CryptoConfig.CreateFromName (m_signature.SignedInfo.CanonicalizationMethod);
-			if (t == null)
-				throw new CryptographicException ("Unknown Canonicalization Method {0}", m_signature.SignedInfo.CanonicalizationMethod);
-			return t;
+			get { return m_signature.KeyInfo; }
+			set { m_signature.KeyInfo = value; }
 		}
 
-		private Stream SignedInfoTransformed () 
+		public XmlElement GetXml ()
 		{
-			Transform t = GetC14NMethod ();
+			// If we have a document context, then return a signature element in this context
+			if (_containingDocument != null)
+				return m_signature.GetXml (_containingDocument);
+			else
+				return m_signature.GetXml ();
+		}
 
-			if (signatureElement == null) {
-				// when creating signatures
-				XmlDocument doc = new XmlDocument ();
-				doc.PreserveWhitespace = true;
-				doc.LoadXml (m_signature.SignedInfo.GetXml ().OuterXml);
-				if (envdoc != null)
-				foreach (XmlAttribute attr in envdoc.DocumentElement.SelectNodes ("namespace::*")) {
-					if (attr.LocalName == "xml")
-						continue;
-					if (attr.Prefix == doc.DocumentElement.Prefix)
-						continue;
-					doc.DocumentElement.SetAttributeNode (doc.ImportNode (attr, true) as XmlAttribute);
-				}
-				t.LoadInput (doc);
-			}
-			else {
-				// when verifying signatures
-				// TODO - check m_signature.SignedInfo.Id
-				XmlElement el = signatureElement.GetElementsByTagName (XmlSignature.ElementNames.SignedInfo, XmlSignature.NamespaceURI) [0] as XmlElement;
-				StringWriter sw = new StringWriter ();
-				XmlTextWriter xtw = new XmlTextWriter (sw);
-				xtw.WriteStartElement (el.Prefix, el.LocalName, el.NamespaceURI);
-
-				// context namespace nodes (except for "xmlns:xml")
-				XmlNodeList nl = el.SelectNodes ("namespace::*");
-				foreach (XmlAttribute attr in nl) {
-					if (attr.ParentNode == el)
-						continue;
-					if (attr.LocalName == "xml")
-						continue;
-					if (attr.Prefix == el.Prefix)
-						continue;
-					attr.WriteTo (xtw);
-				}
-				foreach (XmlNode attr in el.Attributes)
-					attr.WriteTo (xtw);
-				foreach (XmlNode n in el.ChildNodes)
-					n.WriteTo (xtw);
+		public void LoadXml (XmlElement value)
+		{
+			if (value == null)
+				throw new ArgumentNullException (nameof (value));
 
-				xtw.WriteEndElement ();
-				byte [] si = Encoding.UTF8.GetBytes (sw.ToString ());
+			m_signature.LoadXml (value);
 
-				MemoryStream ms = new MemoryStream ();
-				ms.Write (si, 0, si.Length);
-				ms.Position = 0;
+			if (_context == null)
+				_context = value;
 
-				t.LoadInput (ms);
-			}
-			// C14N and C14NWithComments always return a Stream in GetOutput
-			return (Stream) t.GetOutput ();
+			_bCacheValid = false;
 		}
 
-		// reuse hash - most document will always use the same hash
-		private HashAlgorithm GetHash (string algorithm, bool check_hmac) 
-		{
-			HashAlgorithm hash = (HashAlgorithm) hashes [algorithm];
-			if (hash == null) {
-				hash = HashAlgorithm.Create (algorithm);
-				if (hash == null)
-					throw new CryptographicException ("Unknown hash algorithm: {0}", algorithm);
-				hashes.Add (algorithm, hash);
-				// now ready to be used
-			}
-			else {
-				// important before reusing an hash object
-				hash.Initialize ();
-			}
-			// we can sign using any hash algorith, including HMAC, but we can only verify hash (MS compatibility)
-			if (check_hmac && (hash is KeyedHashAlgorithm))
-				return null;
-			return hash;
-		}
+		//
+		// public methods
+		//
 
-		public bool CheckSignature () 
+		public void AddReference (Reference reference)
 		{
-			return (CheckSignatureInternal (null) != null);
+			m_signature.SignedInfo.AddReference (reference);
 		}
 
-		private bool CheckReferenceIntegrity (ArrayList referenceList) 
+		public void AddObject (DataObject dataObject) 
 		{
-			if (referenceList == null)
-				return false;
-
-			// check digest (hash) for every reference
-			foreach (Reference r in referenceList) {
-				// stop at first broken reference
-				byte[] hash = GetReferenceHash (r, true);
-				if (! Compare (r.DigestValue, hash))
-					return false;
-			}
-			return true;
+			m_signature.AddObject (dataObject);
 		}
 
-		public bool CheckSignature (AsymmetricAlgorithm key) 
+		public bool CheckSignature ()
 		{
-			if (key == null)
-				throw new ArgumentNullException ("key");
-			return (CheckSignatureInternal (key) != null);
+			AsymmetricAlgorithm signingKey;
+			return CheckSignatureReturningKey (out signingKey);
 		}
 
-		private AsymmetricAlgorithm CheckSignatureInternal (AsymmetricAlgorithm key)
+		public bool CheckSignatureReturningKey (out AsymmetricAlgorithm signingKey)
 		{
-			pkEnumerator = null;
+			SignedXmlDebugLog.LogBeginSignatureVerification (this, _context);
 
-			if (key != null) {
-				// check with supplied key
-				if (!CheckSignatureWithKey (key))
-					return null;
-			} else {
-				if (Signature.KeyInfo == null)
-					return null;
-				// no supplied key, iterates all KeyInfo
-				while ((key = GetPublicKey ()) != null) {
-					if (CheckSignatureWithKey (key)) {
-						break;
-					}
-				}
-				pkEnumerator = null;
-				if (key == null)
-					return null;
-			}
+			signingKey = null;
+			bool bRet = false;
+			AsymmetricAlgorithm key = null;
 
-			// some parts may need to be downloaded
-			// so where doing it last
-			if (!CheckReferenceIntegrity (m_signature.SignedInfo.References))
-				return null;
+			if (!CheckSignatureFormat ())
+				return false;
 
-			if (manifests != null) {
-				// do not use foreach as a manifest could contain manifests...
-				for (int i=0; i < manifests.Count; i++) {
-					Manifest manifest = new Manifest ((manifests [i] as XmlDocument).DocumentElement);
-					if (! CheckReferenceIntegrity (manifest.References))
-						return null;
+			do {
+				key = GetPublicKey ();
+				if (key != null) {
+					bRet = CheckSignature (key);
+					SignedXmlDebugLog.LogVerificationResult (this, key, bRet);
 				}
-			}
-			return key;
+			} while (key != null && bRet == false);
+
+			signingKey = key;
+			return bRet;
 		}
 
-		// Is the signature (over SignedInfo) valid ?
-		private bool CheckSignatureWithKey (AsymmetricAlgorithm key) 
+		public bool CheckSignature (AsymmetricAlgorithm key)
 		{
-			if (key == null)
+			if (!CheckSignatureFormat ())
 				return false;
 
-			SignatureDescription sd = (SignatureDescription) CryptoConfig.CreateFromName (m_signature.SignedInfo.SignatureMethod);
-			if (sd == null)
+			if (!CheckSignedInfo (key)) {
+				SignedXmlDebugLog.LogVerificationFailure (this, SR.Log_VerificationFailed_SignedInfo);
 				return false;
+			}
 
-			AsymmetricSignatureDeformatter verifier = (AsymmetricSignatureDeformatter) CryptoConfig.CreateFromName (sd.DeformatterAlgorithm);
-			if (verifier == null)
+			// Now is the time to go through all the references and see if their DigestValues are good
+			if (!CheckDigestedReferences ()) {
+				SignedXmlDebugLog.LogVerificationFailure (this, SR.Log_VerificationFailed_References);
 				return false;
+			}
 
-			try {
-				verifier.SetKey (key);
-				verifier.SetHashAlgorithm (sd.DigestAlgorithm);
+			SignedXmlDebugLog.LogVerificationResult (this, key, true);
+			return true;
+		}
 
-				HashAlgorithm hash = GetHash (sd.DigestAlgorithm, true);
-				// get the hash of the C14N SignedInfo element
-				MemoryStream ms = (MemoryStream) SignedInfoTransformed ();
+		public bool CheckSignature (KeyedHashAlgorithm macAlg)
+		{
+			if (!CheckSignatureFormat ())
+				return false;
 
-				byte[] digest = hash.ComputeHash (ms);
-				return verifier.VerifySignature (digest, m_signature.SignatureValue);
+			if (!CheckSignedInfo (macAlg)) {
+				SignedXmlDebugLog.LogVerificationFailure (this, SR.Log_VerificationFailed_SignedInfo);
+				return false;
 			}
-			catch {
-				// e.g. SignatureMethod != AsymmetricAlgorithm type
+
+			if (!CheckDigestedReferences ()) {
+				SignedXmlDebugLog.LogVerificationFailure (this, SR.Log_VerificationFailed_References);
 				return false;
-			} 
+			}
+
+			SignedXmlDebugLog.LogVerificationResult (this, macAlg, true);
+			return true;
 		}
 
-		private bool Compare (byte[] expected, byte[] actual) 
+		public bool CheckSignature (X509Certificate2 certificate, bool verifySignatureOnly)
 		{
-			bool result = ((expected != null) && (actual != null));
-			if (result) {
-				int l = expected.Length;
-				result = (l == actual.Length);
-				if (result) {
-					for (int i=0; i < l; i++) {
-						if (expected[i] != actual[i])
+			if (!verifySignatureOnly) {
+				// Check key usages to make sure it is good for signing.
+				foreach (X509Extension extension in certificate.Extensions) {
+					if (string.Compare (extension.Oid.Value, "2.5.29.15" /* szOID_KEY_USAGE */, StringComparison.OrdinalIgnoreCase) == 0) {
+						X509KeyUsageExtension keyUsage = new X509KeyUsageExtension ();
+						keyUsage.CopyFrom (extension);
+						SignedXmlDebugLog.LogVerifyKeyUsage (this, certificate, keyUsage);
+
+						bool validKeyUsage = (keyUsage.KeyUsages & X509KeyUsageFlags.DigitalSignature) != 0 ||
+						                     (keyUsage.KeyUsages & X509KeyUsageFlags.NonRepudiation) != 0;
+
+						if (!validKeyUsage) {
+							SignedXmlDebugLog.LogVerificationFailure (this, SR.Log_VerificationFailed_X509KeyUsage);
 							return false;
+						}
+						break;
 					}
 				}
-			}
-			return result;
-		}
 
-		public bool CheckSignature (KeyedHashAlgorithm macAlg) 
-		{
-			if (macAlg == null)
-				throw new ArgumentNullException ("macAlg");
+				// Do the chain verification to make sure the certificate is valid.
+				X509Chain chain = new X509Chain ();
+				chain.ChainPolicy.ExtraStore.AddRange (BuildBagOfCerts());
+				bool chainVerified = chain.Build (certificate);
+				SignedXmlDebugLog.LogVerifyX509Chain (this, chain, certificate);
 
-			pkEnumerator = null;
-
-			// Is the signature (over SignedInfo) valid ?
-			Stream s = SignedInfoTransformed ();
-			if (s == null)
-				return false;
-
-			byte[] actual = macAlg.ComputeHash (s);
-			// HMAC signature may be partial and specified by <HMACOutputLength>
-			if (m_signature.SignedInfo.SignatureLength != null) {
-				int length = Int32.Parse (m_signature.SignedInfo.SignatureLength);
-				// we only support signatures with a multiple of 8 bits
-				// and the value must match the signature length
-				if ((length & 7) != 0)
-					throw new CryptographicException ("Signature length must be a multiple of 8 bits.");
-
-				// SignatureLength is in bits (and we works on bytes, only in multiple of 8 bits)
-				// and both values must match for a signature to be valid
-				length >>= 3;
-				if (length != m_signature.SignatureValue.Length)
-					throw new CryptographicException ("Invalid signature length.");
-
-				// is the length "big" enough to make the signature meaningful ? 
-				// we use a minimum of 80 bits (10 bytes) or half the HMAC normal output length
-				// e.g. HMACMD5 output 128 bits but our minimum is 80 bits (not 64 bits)
-				int minimum = Math.Max (10, actual.Length / 2);
-				if (length < minimum)
-					throw new CryptographicException ("HMAC signature is too small");
-
-				if (length < actual.Length) {
-					byte[] trunked = new byte [length];
-					Buffer.BlockCopy (actual, 0, trunked, 0, length);
-					actual = trunked;
+				if (!chainVerified) {
+					SignedXmlDebugLog.LogVerificationFailure (this, SR.Log_VerificationFailed_X509Chain);
+					return false;
 				}
 			}
 
-			if (Compare (m_signature.SignatureValue, actual)) {
-				// some parts may need to be downloaded
-				// so where doing it last
-				return CheckReferenceIntegrity (m_signature.SignedInfo.References);
+			using (AsymmetricAlgorithm publicKey = Utils.GetAnyPublicKey (certificate)) {
+				if (!CheckSignature (publicKey))
+					return false;
 			}
-			return false;
-		}
 
-		[MonoTODO]
-		[ComVisible (false)]
-		public bool CheckSignature (X509Certificate2 certificate, bool verifySignatureOnly)
-		{
-			throw new NotImplementedException ();
+			SignedXmlDebugLog.LogVerificationResult (this, certificate, true);
+			return true;
 		}
 
-		public bool CheckSignatureReturningKey (out AsymmetricAlgorithm signingKey) 
+		public void ComputeSignature ()
 		{
-			signingKey = CheckSignatureInternal (null);
-			return (signingKey != null);
-		}
+			SignedXmlDebugLog.LogBeginSignatureComputation (this, _context);
 
-		public void ComputeSignature () 
-		{
-			DigestReferences ();
+			BuildDigestedReferences ();
+
+			// Load the key
+			AsymmetricAlgorithm key = SigningKey;
 
 			if (key == null)
 				throw new CryptographicException (SR.Cryptography_Xml_LoadKeyFailed);
@@ -665,86 +374,159 @@ namespace System.Security.Cryptography.Xml {
 				if (key is DSA) {
 					SignedInfo.SignatureMethod = XmlDsigDSAUrl;
 				} else if (key is RSA) {
-					// Default to RSA-SHA1
-					SignedInfo.SignatureMethod = XmlDsigRSASHA1Url;
+					if (SignedInfo.SignatureMethod == null)
+						SignedInfo.SignatureMethod = XmlDsigRSADefault;
 				} else {
 					throw new CryptographicException (SR.Cryptography_Xml_CreatedKeyFailed);
 				}
 			}
 
 			// See if there is a signature description class defined in the Config file
-			SignatureDescription signatureDescription = CryptoConfig.CreateFromName (SignedInfo.SignatureMethod) as SignatureDescription;
+			SignatureDescription signatureDescription = CryptoHelpers.CreateFromName (SignedInfo.SignatureMethod) as SignatureDescription;
 			if (signatureDescription == null)
 				throw new CryptographicException (SR.Cryptography_Xml_SignatureDescriptionNotCreated);
-
 			HashAlgorithm hashAlg = signatureDescription.CreateDigest ();
 			if (hashAlg == null)
 				throw new CryptographicException (SR.Cryptography_Xml_CreateHashAlgorithmFailed);
-
-			byte[] hashvalue = hashAlg.ComputeHash (SignedInfoTransformed ());
+			byte[] hashvalue = GetC14NDigest (hashAlg);
 			AsymmetricSignatureFormatter asymmetricSignatureFormatter = signatureDescription.CreateFormatter (key);
 
+			SignedXmlDebugLog.LogSigning (this, key, signatureDescription, hashAlg, asymmetricSignatureFormatter);
 			m_signature.SignatureValue = asymmetricSignatureFormatter.CreateSignature (hashAlg);
 		}
 
-		public void ComputeSignature (KeyedHashAlgorithm macAlg) 
+		public void ComputeSignature (KeyedHashAlgorithm macAlg)
 		{
 			if (macAlg == null)
-				throw new ArgumentNullException ("macAlg");
-
-			string method = null;
-
-			if (macAlg is HMACSHA1) {
-				method = XmlDsigHMACSHA1Url;
-			} else if (macAlg is HMACSHA256) {
-				method = "http://www.w3.org/2001/04/xmldsig-more#hmac-sha256";
-			} else if (macAlg is HMACSHA384) {
-				method = "http://www.w3.org/2001/04/xmldsig-more#hmac-sha384";
-			} else if (macAlg is HMACSHA512) {
-				method = "http://www.w3.org/2001/04/xmldsig-more#hmac-sha512";
-			} else if (macAlg is HMACRIPEMD160) {
-				method = "http://www.w3.org/2001/04/xmldsig-more#hmac-ripemd160";
+				throw new ArgumentNullException (nameof (macAlg));
+
+			HMAC hash = macAlg as HMAC;
+			if (hash == null)
+				throw new CryptographicException (SR.Cryptography_Xml_SignatureMethodKeyMismatch);
+
+			int signatureLength;
+			if (m_signature.SignedInfo.SignatureLength == null)
+				signatureLength = hash.HashSize;
+			else
+				signatureLength = Convert.ToInt32 (m_signature.SignedInfo.SignatureLength, null);
+			// signatureLength should be less than hash size
+			if (signatureLength < 0 || signatureLength > hash.HashSize)
+				throw new CryptographicException (SR.Cryptography_Xml_InvalidSignatureLength);
+			if (signatureLength % 8 != 0)
+				throw new CryptographicException (SR.Cryptography_Xml_InvalidSignatureLength2);
+
+			BuildDigestedReferences ();
+			switch (hash.HashName) {
+			case "SHA1":
+				SignedInfo.SignatureMethod = SignedXml.XmlDsigHMACSHA1Url;
+				break;
+			case "SHA256":
+				SignedInfo.SignatureMethod = SignedXml.XmlDsigMoreHMACSHA256Url;
+				break;
+			case "SHA384":
+				SignedInfo.SignatureMethod = SignedXml.XmlDsigMoreHMACSHA384Url;
+				break;
+			case "SHA512":
+				SignedInfo.SignatureMethod = SignedXml.XmlDsigMoreHMACSHA512Url;
+				break;
+			case "MD5":
+				SignedInfo.SignatureMethod = SignedXml.XmlDsigMoreHMACMD5Url;
+				break;
+			case "RIPEMD160":
+				SignedInfo.SignatureMethod = SignedXml.XmlDsigMoreHMACRIPEMD160Url;
+				break;
+			default:
+				throw new CryptographicException (SR.Cryptography_Xml_SignatureMethodKeyMismatch);
 			}
 
-			if (method == null)
-				throw new CryptographicException ("unsupported algorithm");
+			byte[] hashValue = GetC14NDigest (hash);
 
-			DigestReferences ();
-			m_signature.SignedInfo.SignatureMethod = method;
-			m_signature.SignatureValue = macAlg.ComputeHash (SignedInfoTransformed ());
+			SignedXmlDebugLog.LogSigning (this, hash);
+			m_signature.SignatureValue = new byte [signatureLength / 8];
+			Buffer.BlockCopy (hashValue, 0, m_signature.SignatureValue, 0, signatureLength / 8);
 		}
 
-		public virtual XmlElement GetIdElement (XmlDocument document, string idValue) 
+		//
+		// virtual methods
+		//
+
+		protected virtual AsymmetricAlgorithm GetPublicKey ()
 		{
-			if ((document == null) || (idValue == null))
-				return null;
+			if (KeyInfo == null)
+				throw new CryptographicException (SR.Cryptography_Xml_KeyInfoRequired);
+
+			if (_x509Enum != null) {
+				AsymmetricAlgorithm key = GetNextCertificatePublicKey ();
+				if (key != null)
+					return key;
+			}
 
-			// this works only if there's a DTD or XSD available to define the ID
-			XmlElement xel = document.GetElementById (idValue);
-			if (xel == null) {
-				// search an "undefined" ID
-				xel = (XmlElement) document.SelectSingleNode ("//*[@Id='" + idValue + "']");
-				if (xel == null) {
-					xel = (XmlElement) document.SelectSingleNode ("//*[@ID='" + idValue + "']");
-					if (xel == null) {
-						xel = (XmlElement) document.SelectSingleNode ("//*[@id='" + idValue + "']");
+			if (_keyInfoEnum == null)
+				_keyInfoEnum = KeyInfo.GetEnumerator ();
+
+			// In our implementation, we move to the next KeyInfo clause which is an RSAKeyValue, DSAKeyValue or KeyInfoX509Data
+			while (_keyInfoEnum.MoveNext()) {
+				RSAKeyValue rsaKeyValue = _keyInfoEnum.Current as RSAKeyValue;
+				if (rsaKeyValue != null)
+					return rsaKeyValue.Key;
+
+				DSAKeyValue dsaKeyValue = _keyInfoEnum.Current as DSAKeyValue;
+				if (dsaKeyValue != null)
+					return dsaKeyValue.Key;
+
+				KeyInfoX509Data x509Data = _keyInfoEnum.Current as KeyInfoX509Data;
+				if (x509Data != null) {
+					_x509Collection = Utils.BuildBagOfCerts (x509Data, CertUsageType.Verification);
+					if (_x509Collection.Count > 0) {
+						_x509Enum = _x509Collection.GetEnumerator ();
+						AsymmetricAlgorithm key = GetNextCertificatePublicKey ();
+						if (key != null)
+							return key;
 					}
 				}
 			}
-			return xel;
+
+			return null;
+		}
+
+		private X509Certificate2Collection BuildBagOfCerts ()
+		{
+			X509Certificate2Collection collection = new X509Certificate2Collection ();
+			if (KeyInfo != null) {
+				foreach (KeyInfoClause clause in KeyInfo) {
+					KeyInfoX509Data x509Data = clause as KeyInfoX509Data;
+					if (x509Data != null)
+						collection.AddRange (Utils.BuildBagOfCerts (x509Data, CertUsageType.Verification));
+				}
+			}
+
+			return collection;
+		}
+
+		private AsymmetricAlgorithm GetNextCertificatePublicKey ()
+		{
+			while (_x509Enum.MoveNext ()) {
+				X509Certificate2 certificate = (X509Certificate2)_x509Enum.Current;
+				if (certificate != null)
+					return Utils.GetAnyPublicKey (certificate);
+			}
+
+			return null;
+		}
+
+		public virtual XmlElement GetIdElement (XmlDocument document, string idValue)
+		{
+			return DefaultGetIdElement (document, idValue);
 		}
 
-		internal static XmlElement DefaultGetIdElement(XmlDocument document, string idValue)
+		internal static XmlElement DefaultGetIdElement (XmlDocument document, string idValue)
 		{
 			if (document == null)
 				return null;
 
-			try
-			{
-				XmlConvert.VerifyNCName(idValue);
-			}
-			catch
-			{
+			try {
+				XmlConvert.VerifyNCName (idValue);
+			} catch (XmlException) {
 				// Identifiers are required to be an NCName
 				//   (xml:id version 1.0, part 4, paragraph 2, bullet 1)
 				//
@@ -753,152 +535,515 @@ namespace System.Security.Cryptography.Xml {
 			}
 
 			// Get the element with idValue
-			XmlElement elem = document.GetElementById(idValue);
+			XmlElement elem = document.GetElementById (idValue);
 
-			if (elem != null)
-			{
+			if (elem != null) {
 				// Have to check for duplicate ID values from the DTD.
 
-				XmlDocument docClone = (XmlDocument)document.CloneNode(true);
-				XmlElement cloneElem = docClone.GetElementById(idValue);
+				XmlDocument docClone = (XmlDocument)document.CloneNode (true);
+				XmlElement cloneElem = docClone.GetElementById (idValue);
 
 				// If it's null here we want to know about it, because it means that
 				// GetElementById failed to work across the cloning, and our uniqueness
 				// test is invalid.
-				System.Diagnostics.Debug.Assert(cloneElem != null);
+				System.Diagnostics.Debug.Assert (cloneElem != null);
 
 				// Guard against null anyways
-				if (cloneElem != null)
-				{
-					cloneElem.Attributes.RemoveAll();
+				if (cloneElem != null) {
+					cloneElem.Attributes.RemoveAll ();
 
-					XmlElement cloneElem2 = docClone.GetElementById(idValue);
+					XmlElement cloneElem2 = docClone.GetElementById (idValue);
 
 					if (cloneElem2 != null)
-					{
-						throw new CryptographicException(
-							SR.Cryptography_Xml_InvalidReference);
-					}
+						throw new CryptographicException (SR.Cryptography_Xml_InvalidReference);
 				}
 
 				return elem;
 			}
 
-			elem = GetSingleReferenceTarget(document, "Id", idValue);
+			elem = GetSingleReferenceTarget (document, "Id", idValue);
 			if (elem != null)
 				return elem;
-			elem = GetSingleReferenceTarget(document, "id", idValue);
+			elem = GetSingleReferenceTarget (document, "id", idValue);
 			if (elem != null)
 				return elem;
-			elem = GetSingleReferenceTarget(document, "ID", idValue);
+			elem = GetSingleReferenceTarget (document, "ID", idValue);
 
 			return elem;
 		}
 
-		private static XmlElement GetSingleReferenceTarget(XmlDocument document, string idAttributeName, string idValue)
+		//
+		// private methods
+		//
+
+		private bool _bCacheValid;
+		private byte[] _digestedSignedInfo;
+
+		private static bool DefaultSignatureFormatValidator (SignedXml signedXml)
 		{
-			// idValue has already been tested as an NCName (unless overridden for compatibility), so there's no
-			// escaping that needs to be done here.
-			string xPath = "//*[@" + idAttributeName + "=\"" + idValue + "\"]";
+			// Reject the signature if it uses a truncated HMAC
+			if (signedXml.DoesSignatureUseTruncatedHmac ())
+				return false;
 
-			// http://www.w3.org/TR/xmldsig-core/#sec-ReferenceProcessingModel says that for the form URI="#chapter1":
-			//
-			//   Identifies a node-set containing the element with ID attribute value 'chapter1' ...
-			//
-			// Note that it uses the singular. Therefore, if the match is ambiguous, we should consider the document invalid.
-			//
-			// In this case, we'll treat it the same as having found nothing across all fallbacks (but shortcut so that we don't
-			// fall into a trap of finding a secondary element which wasn't the originally signed one).
+			// Reject the signature if it uses a canonicalization algorithm other than
+			// one of the ones explicitly allowed
+			if (!signedXml.DoesSignatureUseSafeCanonicalizationMethod ())
+				return false;
 
-			XmlNodeList nodeList = document.SelectNodes(xPath);
+			// Otherwise accept it
+			return true;
+		}
 
-			if (nodeList == null || nodeList.Count == 0)
-			{
-				return null;
+		// Validation function to see if the current signature is signed with a truncated HMAC - one which
+		// has a signature length of fewer bits than the whole HMAC output.
+		private bool DoesSignatureUseTruncatedHmac ()
+		{
+			// If we're not using the SignatureLength property, then we're not truncating the signature length
+			if (SignedInfo.SignatureLength == null)
+				return false;
+
+			// See if we're signed witn an HMAC algorithm
+			HMAC hmac = CryptoHelpers.CreateFromName (SignatureMethod) as HMAC;
+			if (hmac == null)
+				return false; // We aren't signed with an HMAC algorithm, so we cannot have a truncated HMAC
+
+			// Figure out how many bits the signature is using
+			int actualSignatureSize = 0;
+			if (!int.TryParse (SignedInfo.SignatureLength, out actualSignatureSize))
+				return true; // If the value wasn't a valid integer, then we'll conservatively reject it all together
+
+			// Make sure the full HMAC signature size is the same size that was specified in the XML
+			// signature.  If the actual signature size is not exactly the same as the full HMAC size, then
+			// reject the signature.
+			return actualSignatureSize != hmac.HashSize;
+		}
+
+		// Validation function to see if the signature uses a canonicalization algorithm from our list
+		// of approved algorithm URIs.
+		private bool DoesSignatureUseSafeCanonicalizationMethod ()
+		{
+			foreach (string safeAlgorithm in SafeCanonicalizationMethods) {
+				if (string.Equals (safeAlgorithm, SignedInfo.CanonicalizationMethod, StringComparison.OrdinalIgnoreCase))
+					return true;
 			}
 
-			if (nodeList.Count == 1)
-			{
-				return nodeList[0] as XmlElement;
+			SignedXmlDebugLog.LogUnsafeCanonicalizationMethod (this, SignedInfo.CanonicalizationMethod, SafeCanonicalizationMethods);
+			return false;
+		}
+
+		private bool ReferenceUsesSafeTransformMethods (Reference reference)
+		{
+			TransformChain transformChain = reference.TransformChain;
+			int transformCount = transformChain.Count;
+
+			for (int i = 0; i < transformCount; i++) {
+				Transform transform = transformChain [i];
+
+				if (!IsSafeTransform (transform.Algorithm))
+					return false;
 			}
 
-			throw new CryptographicException(SR.Cryptography_Xml_InvalidReference);
+			return true;
 		}
 
-		// According to book ".NET Framework Security" this method
-		// iterates all possible keys then return null
-		protected virtual AsymmetricAlgorithm GetPublicKey () 
+		private bool IsSafeTransform (string transformAlgorithm)
 		{
-			if (m_signature.KeyInfo == null)
-				return null;
+			// All canonicalization algorithms are valid transform algorithms.
+			foreach (string safeAlgorithm in SafeCanonicalizationMethods) {
+				if (string.Equals (safeAlgorithm, transformAlgorithm, StringComparison.OrdinalIgnoreCase))
+					return true;
+			}
 
-			if (pkEnumerator == null) {
-				pkEnumerator = m_signature.KeyInfo.GetEnumerator ();
+			foreach (string safeAlgorithm in DefaultSafeTransformMethods) {
+				if (string.Equals (safeAlgorithm, transformAlgorithm, StringComparison.OrdinalIgnoreCase))
+					return true;
 			}
-			
-#if SECURITY_DEP
-			if (_x509Enumerator != null) {
-				if (_x509Enumerator.MoveNext ()) {
-					X509Certificate cert = (X509Certificate) _x509Enumerator.Current;
-					return new X509Certificate2 (cert.GetRawCertData ()).PublicKey.Key;
-				} else {
-					_x509Enumerator = null;
+
+			SignedXmlDebugLog.LogUnsafeTransformMethod (
+				this,
+				transformAlgorithm,
+				SafeCanonicalizationMethods,
+				DefaultSafeTransformMethods);
+
+			return false;
+		}
+
+		// Get a list of the built in canonicalization algorithms, as well as any that the machine admin has
+		// added to the valid set.
+		private static IList<string> KnownCanonicalizationMethods {
+			get {
+				if (s_knownCanonicalizationMethods == null) {
+					// Start with the list that the machine admin added, if any
+					List<string> safeAlgorithms = new List<string> ();
+
+					// Built in algorithms
+					safeAlgorithms.Add (XmlDsigC14NTransformUrl);
+					safeAlgorithms.Add (XmlDsigC14NWithCommentsTransformUrl);
+					safeAlgorithms.Add (XmlDsigExcC14NTransformUrl);
+					safeAlgorithms.Add (XmlDsigExcC14NWithCommentsTransformUrl);
+
+					s_knownCanonicalizationMethods = safeAlgorithms;
 				}
-			}
-#endif
-			while (pkEnumerator.MoveNext ()) {
-				AsymmetricAlgorithm key = null;
-				KeyInfoClause kic = (KeyInfoClause) pkEnumerator.Current;
 
-				if (kic is DSAKeyValue)
-					key = DSA.Create ();
-				else if (kic is RSAKeyValue) 
-					key = RSA.Create ();
+				return s_knownCanonicalizationMethods;
+			}
+		}
 
-				if (key != null) {
-					key.FromXmlString (kic.GetXml ().InnerXml);
-					return key;
+		private static IList<string> DefaultSafeTransformMethods {
+			get {
+				if (s_defaultSafeTransformMethods == null) {
+					List<string> safeAlgorithms = new List<string> ();
+
+					// Built in algorithms
+
+					// KnownCanonicalizationMethods don't need to be added here, because
+					// the validator will automatically accept those.
+					//
+					// xmldsig 6.6.1:
+					//     Any canonicalization algorithm that can be used for
+					//     CanonicalizationMethod can be used as a Transform.
+					safeAlgorithms.Add (XmlDsigEnvelopedSignatureTransformUrl);
+					safeAlgorithms.Add (XmlDsigBase64TransformUrl);
+					safeAlgorithms.Add (XmlLicenseTransformUrl);
+					safeAlgorithms.Add (XmlDecryptionTransformUrl);
+
+					s_defaultSafeTransformMethods = safeAlgorithms;
 				}
 
-#if SECURITY_DEP
-				if (kic is KeyInfoX509Data) {
-					_x509Enumerator = ((KeyInfoX509Data) kic).Certificates.GetEnumerator ();
-					if (_x509Enumerator.MoveNext ()) {
-						X509Certificate cert = (X509Certificate) _x509Enumerator.Current;
-						return new X509Certificate2 (cert.GetRawCertData ()).PublicKey.Key;
+				return s_defaultSafeTransformMethods;
+			}
+		}
+
+		private byte[] GetC14NDigest (HashAlgorithm hash)
+		{
+			bool isKeyedHashAlgorithm = hash is KeyedHashAlgorithm;
+			if (isKeyedHashAlgorithm || !_bCacheValid || !SignedInfo.CacheValid) {
+				string baseUri = (_containingDocument == null ? null : _containingDocument.BaseURI);
+				XmlResolver resolver = (_bResolverSet ? _xmlResolver : new XmlSecureResolver (new XmlUrlResolver (), baseUri));
+				XmlDocument doc = Utils.PreProcessElementInput (SignedInfo.GetXml (), resolver, baseUri);
+
+				// Add non default namespaces in scope
+				CanonicalXmlNodeList namespaces = (_context == null ? null : Utils.GetPropagatedAttributes (_context));
+				SignedXmlDebugLog.LogNamespacePropagation (this, namespaces);
+				Utils.AddNamespaces (doc.DocumentElement, namespaces);
+
+				Transform c14nMethodTransform = SignedInfo.CanonicalizationMethodObject;
+				c14nMethodTransform.Resolver = resolver;
+				c14nMethodTransform.BaseURI = baseUri;
+
+				SignedXmlDebugLog.LogBeginCanonicalization (this, c14nMethodTransform);
+				c14nMethodTransform.LoadInput (doc);
+				SignedXmlDebugLog.LogCanonicalizedOutput (this, c14nMethodTransform);
+				_digestedSignedInfo = c14nMethodTransform.GetDigestedOutput (hash);
+
+				_bCacheValid = !isKeyedHashAlgorithm;
+			}
+			return _digestedSignedInfo;
+		}
+
+		private int GetReferenceLevel (int index, ArrayList references)
+		{
+			if (_refProcessed [index]) return _refLevelCache [index];
+			_refProcessed [index] = true;
+			Reference reference = (Reference)references [index];
+			if (reference.Uri == null || reference.Uri.Length == 0 || (reference.Uri.Length > 0 && reference.Uri [0] != '#')) {
+				_refLevelCache [index] = 0;
+				return 0;
+			}
+			if (reference.Uri.Length > 0 && reference.Uri [0] == '#')
+			{
+				string idref = Utils.ExtractIdFromLocalUri (reference.Uri);
+				if (idref == "xpointer(/)") {
+					_refLevelCache [index] = 0;
+					return 0;
+				}
+				// If this is pointing to another reference
+				for (int j = 0; j < references.Count; ++j) {
+					if (((Reference)references [j]).Id == idref) {
+						_refLevelCache [index] = GetReferenceLevel (j, references) + 1;
+						return (_refLevelCache [index]);
 					}
 				}
-#endif
+				// Then the reference points to an object tag
+				_refLevelCache [index] = 0;
+				return 0;
 			}
-			return null;
+			// Malformed reference
+			throw new CryptographicException (SR.Cryptography_Xml_InvalidReference);
 		}
 
-		public XmlElement GetXml () 
+		private class ReferenceLevelSortOrder : IComparer
 		{
-			return m_signature.GetXml (envdoc);
+			private ArrayList _references;
+
+			public ReferenceLevelSortOrder ()
+			{
+			}
+
+			public ArrayList References
+			{
+				get { return _references; }
+				set { _references = value; }
+			}
+
+			public int Compare (object a, object b)
+			{
+				Reference referenceA = a as Reference;
+				Reference referenceB = b as Reference;
+
+				// Get the indexes
+				int iIndexA = 0;
+				int iIndexB = 0;
+				int i = 0;
+				foreach (Reference reference in References) {
+					if (reference == referenceA) iIndexA = i;
+					if (reference == referenceB) iIndexB = i;
+					i++;
+				}
+
+				int iLevelA = referenceA.SignedXml.GetReferenceLevel (iIndexA, References);
+				int iLevelB = referenceB.SignedXml.GetReferenceLevel (iIndexB, References);
+				return iLevelA.CompareTo (iLevelB);
+			}
 		}
 
-		public void LoadXml (XmlElement value) 
+		private void BuildDigestedReferences ()
 		{
-			if (value == null)
-				throw new ArgumentNullException ("value");
+			// Default the DigestMethod and Canonicalization
+			ArrayList references = SignedInfo.References;
+			// Reset the cache
+			_refProcessed = new bool [references.Count];
+			_refLevelCache = new int [references.Count];
 
-			signatureElement = value;
-			m_signature.LoadXml (value);
+			ReferenceLevelSortOrder sortOrder = new ReferenceLevelSortOrder ();
+			sortOrder.References = references;
+			// Don't alter the order of the references array list
+			ArrayList sortedReferences = new ArrayList ();
 
-			if (_context == null) {
-				_context = value;
+			foreach (Reference reference in references)
+				sortedReferences.Add (reference);
+
+			sortedReferences.Sort (sortOrder);
+
+			CanonicalXmlNodeList nodeList = new CanonicalXmlNodeList ();
+
+			foreach (DataObject obj in m_signature.ObjectList)
+				nodeList.Add (obj.GetXml ());
+
+			foreach (Reference reference in sortedReferences) {
+				if (reference.DigestMethod == null)
+					reference.DigestMethod = XmlDsigDigestDefault;
+
+				SignedXmlDebugLog.LogSigningReference (this, reference);
+
+				reference.UpdateHashValue (_containingDocument, nodeList);
+				// If this reference has an Id attribute, add it
+				if (reference.Id != null)
+					nodeList.Add (reference.GetXml ());
 			}
+		}
+
+		private bool CheckDigestedReferences ()
+		{
+			ArrayList references = m_signature.SignedInfo.References;
+			for (int i = 0; i < references.Count; ++i) {
+				Reference digestedReference = (Reference)references [i];
+
+				if (!ReferenceUsesSafeTransformMethods (digestedReference))
+					return false;
+
+				SignedXmlDebugLog.LogVerifyReference (this, digestedReference);
+				byte[] calculatedHash = null;
+				try {
+					calculatedHash = digestedReference.CalculateHashValue (_containingDocument, m_signature.ReferencedItems);
+				} catch (CryptoSignedXmlRecursionException) {
+					SignedXmlDebugLog.LogSignedXmlRecursionLimit (this, digestedReference);
+					return false;
+				}
+				// Compare both hashes
+				SignedXmlDebugLog.LogVerifyReferenceHash (this, digestedReference, calculatedHash, digestedReference.DigestValue);
+
+				if (!CryptographicEquals (calculatedHash, digestedReference.DigestValue))
+					return false;
+			}
+
+			return true;
+		}
+
+		// Methods _must_ be marked both No Inlining and No Optimization to be fully opted out of optimization.
+		// This is because if a candidate method is inlined, its method level attributes, including the NoOptimization
+		// attribute, are lost. 
+		// This method makes no attempt to disguise the length of either of its inputs. It is assumed the attacker has 
+		// knowledge of the algorithms used, and thus the output length. Length is difficult to properly blind in modern CPUs.
+		[MethodImpl (MethodImplOptions.NoInlining | MethodImplOptions.NoOptimization)]
+		private static bool CryptographicEquals (byte[] a, byte[] b)
+		{
+			System.Diagnostics.Debug.Assert (a != null);
+			System.Diagnostics.Debug.Assert (b != null);
 
-			// Need to give the EncryptedXml object to the 
-			// XmlDecryptionTransform to give it a fighting 
-			// chance at decrypting the document.
-			foreach (Reference r in m_signature.SignedInfo.References) {
-				foreach (Transform t in r.TransformChain) {
-					if (t is XmlDecryptionTransform) 
-						((XmlDecryptionTransform) t).EncryptedXml = EncryptedXml;
+			int result = 0;
+
+			// Short cut if the lengths are not identical
+			if (a.Length != b.Length)
+				return false;
+
+			unchecked
+			{
+				// Normally this caching doesn't matter, but with the optimizer off, this nets a non-trivial speedup.
+				int aLength = a.Length;
+
+				for (int i = 0; i < aLength; i++) {
+					// We use subtraction here instead of XOR because the XOR algorithm gets ever so
+					// slightly faster as more and more differences pile up.
+					// This cannot overflow more than once (and back to 0) because bytes are 1 byte
+					// in length, and result is 4 bytes. The OR propagates all set bytes, so the differences
+					// can't add up and overflow a second time.
+					result = result | (a [i] - b [i]);
 				}
 			}
+
+			return (0 == result);
+		}
+
+		// If we have a signature format validation callback, check to see if this signature's format (not
+		// the signature itself) is valid according to the validator.  A return value of true indicates that
+		// the signature format is acceptable, false means that the format is not valid.
+		private bool CheckSignatureFormat ()
+		{
+			if (_signatureFormatValidator == null) {
+				// No format validator means that we default to accepting the signature.  (This is
+				// effectively compatibility mode with v3.5).
+				return true;
+			}
+
+			SignedXmlDebugLog.LogBeginCheckSignatureFormat (this, _signatureFormatValidator);
+
+			bool formatValid = _signatureFormatValidator (this);
+			SignedXmlDebugLog.LogFormatValidationResult (this, formatValid);
+			return formatValid;
+		}
+
+		private bool CheckSignedInfo (AsymmetricAlgorithm key)
+		{
+			if (key == null)
+				throw new ArgumentNullException (nameof (key));
+
+			SignedXmlDebugLog.LogBeginCheckSignedInfo (this, m_signature.SignedInfo);
+
+			SignatureDescription signatureDescription = CryptoHelpers.CreateFromName (SignatureMethod) as SignatureDescription;
+			if (signatureDescription == null)
+				throw new CryptographicException (SR.Cryptography_Xml_SignatureDescriptionNotCreated);
+
+			// Let's see if the key corresponds with the SignatureMethod 
+			Type ta = Type.GetType (signatureDescription.KeyAlgorithm);
+			if (!IsKeyTheCorrectAlgorithm (key, ta))
+				return false;
+
+			HashAlgorithm hashAlgorithm = signatureDescription.CreateDigest ();
+			if (hashAlgorithm == null)
+				throw new CryptographicException (SR.Cryptography_Xml_CreateHashAlgorithmFailed);
+			byte[] hashval = GetC14NDigest (hashAlgorithm);
+
+			AsymmetricSignatureDeformatter asymmetricSignatureDeformatter = signatureDescription.CreateDeformatter (key);
+			SignedXmlDebugLog.LogVerifySignedInfo (this,
+			                                       key,
+			                                       signatureDescription,
+			                                       hashAlgorithm,
+			                                       asymmetricSignatureDeformatter,
+			                                       hashval,
+			                                       m_signature.SignatureValue);
+			return asymmetricSignatureDeformatter.VerifySignature (hashval, m_signature.SignatureValue);
+		}
+
+		private bool CheckSignedInfo (KeyedHashAlgorithm macAlg)
+		{
+			if (macAlg == null)
+				throw new ArgumentNullException (nameof (macAlg));
+
+			SignedXmlDebugLog.LogBeginCheckSignedInfo (this, m_signature.SignedInfo);
+
+			int signatureLength;
+			if (m_signature.SignedInfo.SignatureLength == null)
+				signatureLength = macAlg.HashSize;
+			else
+				signatureLength = Convert.ToInt32 (m_signature.SignedInfo.SignatureLength, null);
+
+			// signatureLength should be less than hash size
+			if (signatureLength < 0 || signatureLength > macAlg.HashSize)
+				throw new CryptographicException (SR.Cryptography_Xml_InvalidSignatureLength);
+			if (signatureLength % 8 != 0)
+				throw new CryptographicException (SR.Cryptography_Xml_InvalidSignatureLength2);
+			if (m_signature.SignatureValue == null)
+				throw new CryptographicException (SR.Cryptography_Xml_SignatureValueRequired);
+			if (m_signature.SignatureValue.Length != signatureLength / 8)
+				throw new CryptographicException (SR.Cryptography_Xml_InvalidSignatureLength);
+
+			// Calculate the hash
+			byte[] hashValue = GetC14NDigest (macAlg);
+			SignedXmlDebugLog.LogVerifySignedInfo (this, macAlg, hashValue, m_signature.SignatureValue);
+
+			for (int i = 0; i < m_signature.SignatureValue.Length; i++)
+				if (m_signature.SignatureValue [i] != hashValue [i]) return false;
+
+			return true;
+		}
+
+		private static XmlElement GetSingleReferenceTarget (XmlDocument document, string idAttributeName, string idValue)
+		{
+			// idValue has already been tested as an NCName (unless overridden for compatibility), so there's no
+			// escaping that needs to be done here.
+			string xPath = "//*[@" + idAttributeName + "=\"" + idValue + "\"]";
+
+			// http://www.w3.org/TR/xmldsig-core/#sec-ReferenceProcessingModel says that for the form URI="#chapter1":
+			//
+			//   Identifies a node-set containing the element with ID attribute value 'chapter1' ...
+			//
+			// Note that it uses the singular. Therefore, if the match is ambiguous, we should consider the document invalid.
+			//
+			// In this case, we'll treat it the same as having found nothing across all fallbacks (but shortcut so that we don't
+			// fall into a trap of finding a secondary element which wasn't the originally signed one).
+
+			XmlNodeList nodeList = document.SelectNodes (xPath);
+
+			if (nodeList == null || nodeList.Count == 0)
+				return null;
+
+			if (nodeList.Count == 1)
+				return nodeList [0] as XmlElement;
+
+			throw new CryptographicException (SR.Cryptography_Xml_InvalidReference);
+		}
+
+		private static bool IsKeyTheCorrectAlgorithm (AsymmetricAlgorithm key, Type expectedType)
+		{
+			Type actualType = key.GetType ();
+
+			if (actualType == expectedType)
+				return true;
+
+			// This check exists solely for compatibility with 4.6. Normally, we would expect "expectedType" to be the superclass type and
+			// the actualType to be the subclass.
+			if (expectedType.IsSubclassOf (actualType))
+				return true;
+
+			//
+			// "expectedType" comes from the KeyAlgorithm property of a SignatureDescription. The BCL SignatureDescription classes have historically 
+			// denoted provider-specific implementations ("RSACryptoServiceProvider") rather than the base class for the algorithm ("RSA"). We could
+			// change those (at the risk of creating other compat problems) but we have no control over third party SignatureDescriptions.
+			//
+			// So, in the absence of a better approach, walk up the parent hierarchy until we find the ancestor that's a direct subclass of
+			// AsymmetricAlgorithm and treat that as the algorithm identifier.
+			//
+			while (expectedType != null && expectedType.BaseType != typeof (AsymmetricAlgorithm))
+				expectedType = expectedType.BaseType;
+
+			if (expectedType == null)
+				return false; // SignatureDescription specified something that isn't even a subclass of AsymmetricAlgorithm. For compatibility with 4.6, return false rather throw.
+
+			if (actualType.IsSubclassOf (expectedType))
+				return true;
+
+			return false;
 		}
 	}
-}
+}
\ No newline at end of file
diff --git a/mcs/class/System.Security/System.Security.Cryptography.Xml/X509IssuerSerial.cs b/mcs/class/System.Security/System.Security.Cryptography.Xml/X509IssuerSerial.cs
deleted file mode 100644
index 505752920a1..00000000000
--- a/mcs/class/System.Security/System.Security.Cryptography.Xml/X509IssuerSerial.cs
+++ /dev/null
@@ -1,56 +0,0 @@
-//
-// X509IssuerSerial.cs - X509IssuerSerial implementation for XML Encryption
-//
-// Author:
-//      Tim Coleman (tim@timcoleman.com)
-//	Sebastien Pouliot  <sebastien@ximian.com>
-//
-// Copyright (C) Tim Coleman, 2004
-// Copyright (C) 2004-2005 Novell Inc. (http://www.novell.com)
-//
-// Permission is hereby granted, free of charge, to any person obtaining
-// a copy of this software and associated documentation files (the
-// "Software"), to deal in the Software without restriction, including
-// without limitation the rights to use, copy, modify, merge, publish,
-// distribute, sublicense, and/or sell copies of the Software, and to
-// permit persons to whom the Software is furnished to do so, subject to
-// the following conditions:
-// 
-// The above copyright notice and this permission notice shall be
-// included in all copies or substantial portions of the Software.
-// 
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
-// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
-// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
-// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
-// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
-// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
-// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-//
-
-namespace System.Security.Cryptography.Xml {
-
-	public
-	struct X509IssuerSerial {
-
-		private string _issuerName;
-		private string _serialNumber;
-
-		internal X509IssuerSerial (string issuer, string serial) 
-		{
-			_issuerName = issuer;
-			_serialNumber = serial;
-		}
-
-		public string IssuerName {
-			get { return _issuerName; }
-			set { _issuerName = value; }
-		}
-
-		public string SerialNumber {
-			get { return _serialNumber; }
-			set { _serialNumber = value; }
-		}
-	}
-}
-
diff --git a/mcs/class/System.Security/System.Security.Cryptography.Xml/XmlSignature.cs b/mcs/class/System.Security/System.Security.Cryptography.Xml/XmlSignature.cs
deleted file mode 100644
index 1dc64eac1dc..00000000000
--- a/mcs/class/System.Security/System.Security.Cryptography.Xml/XmlSignature.cs
+++ /dev/null
@@ -1,128 +0,0 @@
-//
-// XmlSignature.cs: Handles Xml Signature
-//
-// Author:
-//	Sebastien Pouliot (spouliot@motus.com)
-//	Atsushi Enomoto (atsushi@ximian.com)
-//      Tim Coleman (tim@timcoleman.com)
-//
-// (C) 2003 Motus Technologies Inc. (http://www.motus.com)
-// Copyright (C) Tim Coleman, 2004
-// (C) 2004 Novell Inc.
-//
-
-//
-// Permission is hereby granted, free of charge, to any person obtaining
-// a copy of this software and associated documentation files (the
-// "Software"), to deal in the Software without restriction, including
-// without limitation the rights to use, copy, modify, merge, publish,
-// distribute, sublicense, and/or sell copies of the Software, and to
-// permit persons to whom the Software is furnished to do so, subject to
-// the following conditions:
-// 
-// The above copyright notice and this permission notice shall be
-// included in all copies or substantial portions of the Software.
-// 
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
-// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
-// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
-// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
-// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
-// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
-// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-//
-
-using System;
-using System.Collections;
-using System.Xml;
-
-namespace System.Security.Cryptography.Xml {
-
-	// following the design of WSE
-	internal class XmlSignature {
-
-		public class ElementNames {
-
-			public const string CanonicalizationMethod = "CanonicalizationMethod";
-			public const string DigestMethod = "DigestMethod";
-			public const string DigestValue = "DigestValue";
-			public const string DSAKeyValue = "DSAKeyValue";
-			public const string EncryptedKey = "EncryptedKey";
-			public const string HMACOutputLength = "HMACOutputLength";
-			public const string KeyInfo = "KeyInfo";
-			public const string KeyName = "KeyName";
-			public const string KeyValue = "KeyValue";
-			public const string Manifest = "Manifest";
-			public const string Object = "Object";
-			public const string Reference = "Reference";
-			public const string RetrievalMethod = "RetrievalMethod";
-			public const string RSAKeyValue = "RSAKeyValue";
-			public const string Signature = "Signature";
-			public const string SignatureMethod = "SignatureMethod";
-			public const string SignatureValue = "SignatureValue";
-			public const string SignedInfo = "SignedInfo";
-			public const string Transform = "Transform";
-			public const string Transforms = "Transforms";
-			public const string X509Data = "X509Data";
-			public const string X509IssuerSerial = "X509IssuerSerial";
-			public const string X509IssuerName = "X509IssuerName";
-			public const string X509SerialNumber = "X509SerialNumber";
-			public const string X509SKI = "X509SKI";
-			public const string X509SubjectName = "X509SubjectName";
-			public const string X509Certificate = "X509Certificate";
-			public const string X509CRL = "X509CRL";
-
-			public ElementNames () {}
-		}
-
-		public class AttributeNames {
-
-			public const string Algorithm = "Algorithm";
-			public const string Encoding = "Encoding";
-			public const string Id = "Id";
-			public const string MimeType = "MimeType";
-			public const string Type = "Type";
-			public const string URI = "URI";
-
-			public AttributeNames () {}
-		}
-
-		public class Uri {
-			public const string Manifest = "http://www.w3.org/2000/09/xmldsig#Manifest";
-		}
-
-		public const string NamespaceURI = "http://www.w3.org/2000/09/xmldsig#";
-		public const string Prefix = "ds";
-
-		public XmlSignature () 
-		{
-		}
-
-		public static XmlElement GetChildElement (XmlElement xel, string element, string ns)
-		{
-			for (int i = 0; i < xel.ChildNodes.Count; i++) {
-				XmlNode n = xel.ChildNodes [i];
-				if (n.NodeType == XmlNodeType.Element && n.LocalName == element && n.NamespaceURI == ns)
-					return n as XmlElement;
-			}
-			return null;
-		}
-
-		public static string GetAttributeFromElement (XmlElement xel, string attribute, string element) 
-		{
-			XmlElement el = GetChildElement (xel, element, XmlSignature.NamespaceURI);
-			return el != null ? el.GetAttribute (attribute) : null;
-		}
-
-		public static XmlElement [] GetChildElements (XmlElement xel, string element)
-		{
-			ArrayList al = new ArrayList ();
-			for (int i = 0; i < xel.ChildNodes.Count; i++) {
-				XmlNode n = xel.ChildNodes [i];
-				if (n.NodeType == XmlNodeType.Element && n.LocalName == element && n.NamespaceURI == XmlSignature.NamespaceURI)
-					al.Add (n);
-			}
-			return al.ToArray (typeof (XmlElement)) as XmlElement [];
-		}
-	}
-}
diff --git a/mcs/class/System.Security/System.Security.dll.sources b/mcs/class/System.Security/System.Security.dll.sources
index 75c0a6f9b0a..e77373a0ebe 100644
--- a/mcs/class/System.Security/System.Security.dll.sources
+++ b/mcs/class/System.Security/System.Security.dll.sources
@@ -1,5 +1,5 @@
 #include common_System.Security.dll.sources
-corefx/SR.cs
+
 Mono.Security.Cryptography/ManagedProtection.cs
 Mono.Security.Cryptography/NativeDapiProtection.cs
 System.Security.Cryptography/MemoryProtectionScope.cs
@@ -13,6 +13,8 @@ System.Security.Cryptography.Pkcs/SignerInfoEnumerator.cs
 ../System.Core/System.Security.Cryptography.X509Certificates/RSACertificateExtensions.cs
 System.Security.Cryptography.X509Certificates/X509Certificate2UI.cs
 System.Security.Cryptography.X509Certificates/X509SelectionFlag.cs
+
+# System.Security.Cryptography.Xml
 ../../../external/corefx/src/System.Security.Cryptography.Xml/src/System/Security/Cryptography/Xml/AncestralNamespaceContextManager.cs
 ../../../external/corefx/src/System.Security.Cryptography.Xml/src/System/Security/Cryptography/Xml/AttributeSortOrder.cs
 ../../../external/corefx/src/System.Security.Cryptography.Xml/src/System/Security/Cryptography/Xml/C14NAncestralNamespaceContextManager.cs
@@ -57,9 +59,8 @@ System.Security.Cryptography.X509Certificates/X509SelectionFlag.cs
 ../../../external/corefx/src/System.Security.Cryptography.Xml/src/System/Security/Cryptography/Xml/KeyInfoName.cs
 ../../../external/corefx/src/System.Security.Cryptography.Xml/src/System/Security/Cryptography/Xml/KeyInfoNode.cs
 ../../../external/corefx/src/System.Security.Cryptography.Xml/src/System/Security/Cryptography/Xml/KeyInfoRetrievalMethod.cs
-System.Security.Cryptography.Xml/KeyInfoX509Data.cs
+../../../external/corefx/src/System.Security.Cryptography.Xml/src/System/Security/Cryptography/Xml/KeyInfoX509Data.cs
 ../../../external/corefx/src/System.Security.Cryptography.Xml/src/System/Security/Cryptography/Xml/KeyReference.cs
-System.Security.Cryptography.Xml/Manifest.cs
 ../../../external/corefx/src/System.Security.Cryptography.Xml/src/System/Security/Cryptography/Xml/MyXmlDocument.cs
 ../../../external/corefx/src/System.Security.Cryptography.Xml/src/System/Security/Cryptography/Xml/NamespaceFrame.cs
 ../../../external/corefx/src/System.Security.Cryptography.Xml/src/System/Security/Cryptography/Xml/NamespaceSortOrder.cs
@@ -72,8 +73,8 @@ System.Security.Cryptography.Xml/Manifest.cs
 ../../../external/corefx/src/System.Security.Cryptography.Xml/src/System/Security/Cryptography/Xml/RSAPKCS1SHA384SignatureDescription.cs
 ../../../external/corefx/src/System.Security.Cryptography.Xml/src/System/Security/Cryptography/Xml/RSAPKCS1SHA512SignatureDescription.cs
 ../../../external/corefx/src/System.Security.Cryptography.Xml/src/System/Security/Cryptography/Xml/RSAPKCS1SignatureDescription.cs
-System.Security.Cryptography.Xml/Signature.cs
-System.Security.Cryptography.Xml/SignedInfo.cs
+../../../external/corefx/src/System.Security.Cryptography.Xml/src/System/Security/Cryptography/Xml/Signature.cs
+../../../external/corefx/src/System.Security.Cryptography.Xml/src/System/Security/Cryptography/Xml/SignedInfo.cs
 System.Security.Cryptography.Xml/SignedXml.cs
 ../../../external/corefx/src/System.Security.Cryptography.Xml/src/System/Security/Cryptography/Xml/SignedXmlDebugLog.cs
 ../../../external/corefx/src/System.Security.Cryptography.Xml/src/System/Security/Cryptography/Xml/SymmetricKeyWrap.cs
@@ -90,8 +91,8 @@ System.Security.Cryptography.Xml/SignedXml.cs
 ../../../external/corefx/src/System.Security.Cryptography.Xml/src/System/Security/Cryptography/Xml/XmlDsigXPathTransform.cs
 ../../../external/corefx/src/System.Security.Cryptography.Xml/src/System/Security/Cryptography/Xml/XmlDsigXsltTransform.cs
 ../../../external/corefx/src/System.Security.Cryptography.Xml/src/System/Security/Cryptography/Xml/XmlLicenseTransform.cs
-System.Security.Cryptography.Xml/XmlSignature.cs
-../../build/common/MonoTODOAttribute.cs
+
+# System.Security.Permissions
 System.Security.Permissions/DataProtectionPermission.cs
 System.Security.Permissions/DataProtectionPermissionAttribute.cs
 System.Security.Permissions/DataProtectionPermissionFlags.cs
diff --git a/mcs/class/System.Security/Test/System.Security.Cryptography.Xml/EncryptedXmlTest.cs b/mcs/class/System.Security/Test/System.Security.Cryptography.Xml/EncryptedXmlTest.cs
index 7ff9beef391..82fc0fb433a 100644
--- a/mcs/class/System.Security/Test/System.Security.Cryptography.Xml/EncryptedXmlTest.cs
+++ b/mcs/class/System.Security/Test/System.Security.Cryptography.Xml/EncryptedXmlTest.cs
@@ -180,11 +180,22 @@ namespace MonoTests.System.Security.Cryptography.Xml
 			Assert.IsNull (ex.GetIdElement (null, "value"));
 		}
 
+		[TestCase (null, TestName = "null")]
+		[TestCase ("", TestName = "empty")]
+		public void GetIdElement_WhenElementNameMustBeNonColonizedAndItIsNotProvided_ThrowsArgumentNullException (string elementName)
+		{
+			var sut = new EncryptedXml ();
+
+			var ex = Assert.Throws<ArgumentNullException> (() => sut.GetIdElement (new XmlDocument (), elementName), "Exception");
+			Assert.That (ex.ParamName, Is.EqualTo ("name"), "ParamName");
+		}
+
 		[Test]
-		public void GetIdElement_StringNull ()
+		public void GetIdElement_WhenElementNameMustBeNonColonizedAndItContainsColon_ReturnsNull ()
 		{
-			EncryptedXml ex = new EncryptedXml ();
-			Assert.IsNull (ex.GetIdElement (new XmlDocument (), null));
+			var sut = new EncryptedXml ();
+
+			Assert.That (sut.GetIdElement (new XmlDocument (), "t:test"), Is.Null);
 		}
 
 		[Test]
diff --git a/mcs/class/System.Security/Test/System.Security.Cryptography.Xml/SignedXmlTest.cs b/mcs/class/System.Security/Test/System.Security.Cryptography.Xml/SignedXmlTest.cs
index b5baf86ebdb..2a6aae4f774 100644
--- a/mcs/class/System.Security/Test/System.Security.Cryptography.Xml/SignedXmlTest.cs
+++ b/mcs/class/System.Security/Test/System.Security.Cryptography.Xml/SignedXmlTest.cs
@@ -253,7 +253,7 @@ namespace MonoTests.System.Security.Cryptography.Xml {
 			signedXml.ComputeSignature ();
 
 			Assert.IsNull (signedXml.SigningKeyName, "SigningKeyName");
-			Assert.AreEqual (SignedXml.XmlDsigRSASHA1Url, signedXml.SignatureMethod, "SignatureMethod");
+			Assert.AreEqual (SignedXml.XmlDsigRSASHA256Url, signedXml.SignatureMethod, "SignatureMethod");
 			Assert.AreEqual (128, signedXml.SignatureValue.Length, "SignatureValue");
 			Assert.IsNull (signedXml.SigningKeyName, "SigningKeyName");
 
@@ -638,13 +638,13 @@ namespace MonoTests.System.Security.Cryptography.Xml {
 		public void DataReferenceToNonDataObject ()
 		{
 			XmlDocument doc = new XmlDocument ();
-			doc.LoadXml ("<foo Id='id:1'/>");
+			doc.LoadXml ("<foo Id='test'/>");
 			SignedXml signedXml = new SignedXml (doc);
 			DSA key = DSA.Create ();
 			signedXml.SigningKey = key;
 
 			Reference reference = new Reference ();
-			reference.Uri = "#id:1";
+			reference.Uri = "#test";
 
 			XmlDsigC14NTransform t = new XmlDsigC14NTransform ();
 			reference.AddTransform (t);
@@ -707,12 +707,30 @@ namespace MonoTests.System.Security.Cryptography.Xml {
 			return sw.ToString ();
 		}
 
+		[TestCase (null, TestName = "null")]
+		[TestCase ("", TestName = "empty")]
+		public void GetIdElement_WhenElementNameMustBeNonColonizedAndItIsNotProvided_ThrowsArgumentNullException (string elementName)
+		{
+			var sut = new SignedXml ();
+
+			var ex = Assert.Throws<ArgumentNullException> (() => sut.GetIdElement (new XmlDocument (), elementName), "Exception");
+			Assert.That (ex.ParamName, Is.EqualTo ("name"), "ParamName");
+		}
+
 		[Test]
-		public void GetIdElement_Null ()
+		public void GetIdElement_WhenElementNameMustBeNonColonizedAndItContainsColon_ReturnsNull ()
 		{
-			SignedXml sign = new SignedXml ();
-			Assert.IsNull (sign.GetIdElement (null, "value"));
-			Assert.IsNull (sign.GetIdElement (new XmlDocument (), null));
+			var sut = new SignedXml ();
+
+			Assert.That (sut.GetIdElement (new XmlDocument (), "t:test"), Is.Null);
+		}
+
+		[Test]
+		public void GetIdElement_WhenXmlDocumentIsNotProvided_ReturnsNull ()
+		{
+			var sut = new SignedXml ();
+
+			Assert.That (sut.GetIdElement (null, "value"), Is.Null);
 		}
 
 		[Test]
@@ -789,6 +807,7 @@ namespace MonoTests.System.Security.Cryptography.Xml {
 			SignedXml signedXml = new SignedXml (doc);
 			signedXml.SigningKey = cert.PrivateKey;
 			signedXml.SignedInfo.CanonicalizationMethod = SignedXml.XmlDsigExcC14NTransformUrl;
+			signedXml.SignedInfo.SignatureMethod = SignedXml.XmlDsigRSASHA1Url;
 
 			Reference reference = new Reference ();
 			reference.DigestMethod = SignedXml.XmlDsigSHA1Url;
@@ -1408,13 +1427,6 @@ namespace MonoTests.System.Security.Cryptography.Xml {
 			// verify MS-generated signature
 			Assert.IsTrue (sign.CheckSignature (new HMACRIPEMD160 (hmackey)));
 		}
-		// CVE-2009-0217
-		// * a 0-length signature is the worse case - it accepts anything
-		// * between 1-7 bits length are considered invalid (not a multiple of 8)
-		// * a 8 bits signature would have one chance, out of 256, to be valid
-		// * and so on... until we hit (output-length / 2) or 80 bits (see ERRATUM)
-
-		static bool erratum = true; // xmldsig erratum for CVE-2009-0217
 
 		static SignedXml GetSignedXml (string xml)
 		{
@@ -1426,31 +1438,15 @@ namespace MonoTests.System.Security.Cryptography.Xml {
 			return sign;
 		}
 
-		static void CheckErratum (SignedXml signed, KeyedHashAlgorithm hmac, string message)
-		{
-			if (erratum) {
-				try {
-					signed.CheckSignature (hmac);
-					Assert.Fail (message + ": unexcepted success");
-				}
-				catch (CryptographicException) {
-				}
-				catch (Exception e) {
-					Assert.Fail (message + ": unexcepted " + e.ToString ());
-				}
-			} else {
-				Assert.IsTrue (signed.CheckSignature (hmac), message);
-			}
-		}
-
-		private void HmacMustBeMultipleOfEightBits (int bits)
+		[Test]
+		public void CheckSignature_WhenHmacOutputLengthIsNotMultipleOf8_ThrowsCryptographicException ()
 		{
 			string xml = @"<?xml version=""1.0"" encoding=""UTF-8""?>
 <Signature xmlns=""http://www.w3.org/2000/09/xmldsig#"">
   <SignedInfo>
     <CanonicalizationMethod Algorithm=""http://www.w3.org/TR/2001/REC-xml-c14n-20010315"" />
     <SignatureMethod Algorithm=""http://www.w3.org/2000/09/xmldsig#hmac-sha1"" >
-      <HMACOutputLength>{0}</HMACOutputLength>
+      <HMACOutputLength>81</HMACOutputLength>
     </SignatureMethod>
     <Reference URI=""#object"">
       <DigestMethod Algorithm=""http://www.w3.org/2000/09/xmldsig#sha1"" />
@@ -1463,96 +1459,41 @@ namespace MonoTests.System.Security.Cryptography.Xml {
   <Object Id=""object"">some other text</Object>
 </Signature>
 ";
-			SignedXml sign = GetSignedXml (String.Format (xml, bits));
-			// only multiple of 8 bits are supported
-			sign.CheckSignature (new HMACSHA1 (Encoding.ASCII.GetBytes ("secret")));
-		}
 
-		[Test]
-		public void HmacMustBeMultipleOfEightBits ()
-		{
-			for (int i = 1; i < 160; i++) {
-				// The .NET framework only supports multiple of 8 bits
-				if (i % 8 == 0)
-					continue;
-
-				try {
-					HmacMustBeMultipleOfEightBits (i);
-					Assert.Fail ("Unexpected Success " + i.ToString ());
-				}
-				catch (CryptographicException) {
-				}
-				catch (Exception e) {
-					Assert.Fail ("Unexpected Exception " + i.ToString () + " : " + e.ToString ());
-				}
-			}
-		}
+			var sut = GetSignedXml (xml);
+			sut.SignatureFormatValidator = null;
 
-		[Test]
-		[Category ("NotDotNet")] // will fail until a fix is available
-		public void VerifyHMAC_ZeroLength ()
-		{
-			string xml = @"<?xml version=""1.0"" encoding=""UTF-8""?>
-<Signature xmlns=""http://www.w3.org/2000/09/xmldsig#"">
-  <SignedInfo>
-    <CanonicalizationMethod Algorithm=""http://www.w3.org/TR/2001/REC-xml-c14n-20010315"" />
-    <SignatureMethod Algorithm=""http://www.w3.org/2000/09/xmldsig#hmac-sha1"" >
-      <HMACOutputLength>0</HMACOutputLength>
-    </SignatureMethod>
-    <Reference URI=""#object"">
-      <DigestMethod Algorithm=""http://www.w3.org/2000/09/xmldsig#sha1"" />
-      <DigestValue>nz4GS0NbH2SrWlD/4fX313CoTzc=</DigestValue>
-    </Reference>
-  </SignedInfo>
-  <SignatureValue>
-  </SignatureValue>
-  <Object Id=""object"">some other text</Object>
-</Signature>
-";
-			SignedXml sign = GetSignedXml (xml);
-
-			CheckErratum (sign, new HMACSHA1 (Encoding.ASCII.GetBytes ("no clue")), "1");
-			CheckErratum (sign, new HMACSHA1 (Encoding.ASCII.GetBytes ("")), "2");
-			CheckErratum (sign, new HMACSHA1 (Encoding.ASCII.GetBytes ("oops")), "3");
-			CheckErratum (sign, new HMACSHA1 (Encoding.ASCII.GetBytes ("secret")), "4");
+			var ex = Assert.Throws<CryptographicException> (() => sut.CheckSignature (new HMACSHA1 (Encoding.ASCII.GetBytes ("secret"))), "Exception");
+			Assert.That (ex.Message, Is.StringContaining ("multiple of 8").IgnoreCase, "Message");
 		}
 
 		[Test]
-		[Category ("NotDotNet")] // will fail until a fix is available
-		public void VerifyHMAC_SmallerThanMinimumLength ()
+		public void CheckSignature_WhenDefaultSignatureFormatValidatorIsUsedAndSignatureUsesTruncatedHmac_ReturnsFalse ()
 		{
-			// 72 is a multiple of 8 but smaller than the minimum of 80 bits
-			string xml = @"<Signature xmlns=""http://www.w3.org/2000/09/xmldsig#""><SignedInfo><CanonicalizationMethod Algorithm=""http://www.w3.org/TR/2001/REC-xml-c14n-20010315"" /><SignatureMethod Algorithm=""http://www.w3.org/2000/09/xmldsig#hmac-sha1""><HMACOutputLength>72</HMACOutputLength></SignatureMethod><Reference URI=""#object""><DigestMethod Algorithm=""http://www.w3.org/2000/09/xmldsig#sha1"" /><DigestValue>nz4GS0NbH2SrWlD/4fX313CoTzc=</DigestValue></Reference></SignedInfo><SignatureValue>2dimB+P5Aw5K</SignatureValue><Object Id=""object"">some other text</Object></Signature>";
-			SignedXml sign = GetSignedXml (xml);
-			CheckErratum (sign, new HMACSHA1 (Encoding.ASCII.GetBytes ("secret")), "72");
-		}
+			// The HMAC output length is 128, which is a half of HMACSHA256 that we're going to use.
+			string xml = @"<Signature xmlns=""http://www.w3.org/2000/09/xmldsig#""><SignedInfo><CanonicalizationMethod Algorithm=""http://www.w3.org/TR/2001/REC-xml-c14n-20010315"" /><SignatureMethod Algorithm=""http://www.w3.org/2001/04/xmldsig-more#hmac-sha256""><HMACOutputLength>128</HMACOutputLength></SignatureMethod><Reference URI=""#object""><DigestMethod Algorithm=""http://www.w3.org/2000/09/xmldsig#sha1"" /><DigestValue>nz4GS0NbH2SrWlD/4fX313CoTzc=</DigestValue></Reference></SignedInfo><SignatureValue>aegpvkAwOL8gN/CjSnW6qw==</SignatureValue><Object Id=""object"">some other text</Object></Signature>";
+			var sut = GetSignedXml (xml);
 
-		[Test]
-		public void VerifyHMAC_MinimumLength ()
-		{
-			// 80 bits is the minimum (and the half-size of HMACSHA1)
-			string xml = @"<Signature xmlns=""http://www.w3.org/2000/09/xmldsig#""><SignedInfo><CanonicalizationMethod Algorithm=""http://www.w3.org/TR/2001/REC-xml-c14n-20010315"" /><SignatureMethod Algorithm=""http://www.w3.org/2000/09/xmldsig#hmac-sha1""><HMACOutputLength>80</HMACOutputLength></SignatureMethod><Reference URI=""#object""><DigestMethod Algorithm=""http://www.w3.org/2000/09/xmldsig#sha1"" /><DigestValue>nz4GS0NbH2SrWlD/4fX313CoTzc=</DigestValue></Reference></SignedInfo><SignatureValue>jVQPtLj61zNYjw==</SignatureValue><Object Id=""object"">some other text</Object></Signature>";
-			SignedXml sign = GetSignedXml (xml);
-			Assert.IsTrue (sign.CheckSignature (new HMACSHA1 (Encoding.ASCII.GetBytes ("secret"))));
-		}
-		[Test]
-		[Category ("NotDotNet")] // will fail until a fix is available
-		public void VerifyHMAC_SmallerHalfLength ()
-		{
-			// 80bits is smaller than the half-size of HMACSHA256
-			string xml = @"<Signature xmlns=""http://www.w3.org/2000/09/xmldsig#""><SignedInfo><CanonicalizationMethod Algorithm=""http://www.w3.org/TR/2001/REC-xml-c14n-20010315"" /><SignatureMethod Algorithm=""http://www.w3.org/2001/04/xmldsig-more#hmac-sha256""><HMACOutputLength>80</HMACOutputLength></SignatureMethod><Reference URI=""#object""><DigestMethod Algorithm=""http://www.w3.org/2000/09/xmldsig#sha1"" /><DigestValue>nz4GS0NbH2SrWlD/4fX313CoTzc=</DigestValue></Reference></SignedInfo><SignatureValue>vPtw7zKVV/JwQg==</SignatureValue><Object Id=""object"">some other text</Object></Signature>";
-			SignedXml sign = GetSignedXml (xml);
-			CheckErratum (sign, new HMACSHA256 (Encoding.ASCII.GetBytes ("secret")), "80");
+			// Although the XML Signature standard allows using truncated HMACs (with some limitations),
+			// .NET Framework, by default, doesn't allow using them, since it may result in security issues.
+			Assert.That (sut.CheckSignature (new HMACSHA256 (Encoding.ASCII.GetBytes ("secret"))), Is.False);
 		}
 
 		[Test]
-		public void VerifyHMAC_HalfLength ()
+		public void CheckSignature_WhenDefaultSignatureFormatValidatorIsNotUsedAndSignatureUsesTruncatedHmac_ReturnsTrue ()
 		{
-			// 128 is the half-size of HMACSHA256
+			// The HMAC output length is 128, which is a half of HMACSHA256 that we're going to use.
 			string xml = @"<Signature xmlns=""http://www.w3.org/2000/09/xmldsig#""><SignedInfo><CanonicalizationMethod Algorithm=""http://www.w3.org/TR/2001/REC-xml-c14n-20010315"" /><SignatureMethod Algorithm=""http://www.w3.org/2001/04/xmldsig-more#hmac-sha256""><HMACOutputLength>128</HMACOutputLength></SignatureMethod><Reference URI=""#object""><DigestMethod Algorithm=""http://www.w3.org/2000/09/xmldsig#sha1"" /><DigestValue>nz4GS0NbH2SrWlD/4fX313CoTzc=</DigestValue></Reference></SignedInfo><SignatureValue>aegpvkAwOL8gN/CjSnW6qw==</SignatureValue><Object Id=""object"">some other text</Object></Signature>";
-			SignedXml sign = GetSignedXml (xml);
-			Assert.IsTrue (sign.CheckSignature (new HMACSHA256 (Encoding.ASCII.GetBytes ("secret"))));
+			var sut = GetSignedXml (xml);
+
+			// By default, .NET Framework doesn't allow using truncated HMACs, since it may lead to security issues.
+			// That being said, the XML Signature standard allows using truncated HMACs, but with some limitations.
+			// It's possible to use truncated HMACs by using a custom signature format validator, or not using it at all.
+			sut.SignatureFormatValidator = null;
+
+			Assert.That (sut.CheckSignature (new HMACSHA256 (Encoding.ASCII.GetBytes ("secret"))), Is.True);
 		}
+
 		[Test]
 		public void VerifyHMAC_FullLength ()
 		{
@@ -1562,8 +1503,7 @@ namespace MonoTests.System.Security.Cryptography.Xml {
 		}
 
 		[Test]
-		[ExpectedException (typeof (CryptographicException))]
-		public void VerifyHMAC_HMACOutputLength_Signature_Mismatch ()
+		public void CheckSignature_WhenSignatureLengthIsGreaterThanHmacOutputLength_ThrowsCryptographicException ()
 		{
 			string xml = @"<?xml version=""1.0"" encoding=""UTF-8""?>
 <Signature xmlns=""http://www.w3.org/2000/09/xmldsig#"">
@@ -1582,13 +1522,15 @@ namespace MonoTests.System.Security.Cryptography.Xml {
   <Object Id=""object"">some other text</Object>
 </Signature>
 ";
-			SignedXml sign = GetSignedXml (xml);
-			sign.CheckSignature (new HMACSHA1 (Encoding.ASCII.GetBytes ("no clue")));
+			var sut = GetSignedXml (xml);
+			sut.SignatureFormatValidator = null;
+
+			var ex = Assert.Throws<CryptographicException> (() => sut.CheckSignature (new HMACSHA1 (Encoding.ASCII.GetBytes ("no clue"))), "Exception");
+			Assert.That (ex.Message, Is.StringContaining ("length of the signature").IgnoreCase, "Message");
 		}
 
 		[Test]
-		[ExpectedException (typeof (FormatException))]
-		public void VerifyHMAC_HMACOutputLength_Invalid ()
+		public void CheckSignature_WhenHmacOutputLengthIsInvalid_ThrowsFormatException ()
 		{
 			string xml = @"<?xml version=""1.0"" encoding=""UTF-8""?>
 <Signature xmlns=""http://www.w3.org/2000/09/xmldsig#"">
@@ -1607,8 +1549,10 @@ namespace MonoTests.System.Security.Cryptography.Xml {
   <Object Id=""object"">some other text</Object>
 </Signature>
 ";
-			SignedXml sign = GetSignedXml (xml);
-			sign.CheckSignature (new HMACSHA1 (Encoding.ASCII.GetBytes ("no clue")));
+			var sut = GetSignedXml (xml);
+			sut.SignatureFormatValidator = null;
+
+			Assert.Throws<FormatException> (() => sut.CheckSignature (new HMACSHA1 (Encoding.ASCII.GetBytes ("no clue"))));
 		}
 
 		[Test]
@@ -1628,7 +1572,7 @@ namespace MonoTests.System.Security.Cryptography.Xml {
 		}
 
 		[Test]
-		public void ComputeSignature_WhenSignatureMethodIsNotSpecifiedAndRsaSigningKeyIsUsed_UsesRsaSha1Algorithm ()
+		public void ComputeSignature_WhenSignatureMethodIsNotSpecifiedAndRsaSigningKeyIsUsed_UsesRsaSha256Algorithm ()
 		{
 			var unsignedXml = new XmlDocument ();
 			unsignedXml.LoadXml ("<test />");
@@ -1651,7 +1595,7 @@ namespace MonoTests.System.Security.Cryptography.Xml {
 				string.Format ("/{0}:SignedInfo/{0}:SignatureMethod", XmlDsigNamespacePrefix),
 				namespaceManager);
 
-			Assert.That (signatureMethodElement.Attributes["Algorithm"].Value, Is.EqualTo (SignedXml.XmlDsigRSASHA1Url));
+			Assert.That (signatureMethodElement.Attributes["Algorithm"].Value, Is.EqualTo (SignedXml.XmlDsigRSASHA256Url));
 		}
 
 		[Test]
diff --git a/mcs/class/System.Security/common_System.Security.dll.sources b/mcs/class/System.Security/common_System.Security.dll.sources
index 5a34119a3ad..321dc74da7c 100644
--- a/mcs/class/System.Security/common_System.Security.dll.sources
+++ b/mcs/class/System.Security/common_System.Security.dll.sources
@@ -1,12 +1,18 @@
 Assembly/AssemblyInfo.cs
+corefx/SR.cs
+
 ../../build/common/Consts.cs
 ../../build/common/Locale.cs
 ../../build/common/MonoTODOAttribute.cs
+
+# System.Security.Cryptography
 System.Security.Cryptography/CryptographicAttribute.cs
 System.Security.Cryptography/CryptographicAttributeCollection.cs
 System.Security.Cryptography/CryptographicAttributeEnumerator.cs
 System.Security.Cryptography/DataProtectionScope.cs
 System.Security.Cryptography/ProtectedData.cs
+
+# System.Security.Cryptography.Pkcs
 System.Security.Cryptography.Pkcs/AlgorithmIdentifier.cs
 System.Security.Cryptography.Pkcs/CmsRecipient.cs
 System.Security.Cryptography.Pkcs/CmsRecipientCollection.cs
@@ -30,5 +36,6 @@ System.Security.Cryptography.Pkcs/SubjectIdentifier.cs
 System.Security.Cryptography.Pkcs/SubjectIdentifierOrKey.cs
 System.Security.Cryptography.Pkcs/SubjectIdentifierOrKeyType.cs
 System.Security.Cryptography.Pkcs/SubjectIdentifierType.cs
-System.Security.Cryptography.Xml/X509IssuerSerial.cs
 
+# System.Security.Cryptography.Xml
+../../../external/corefx/src/System.Security.Cryptography.Xml/src/System/Security/Cryptography/Xml/X509IssuerSerial.cs