mcs/class/System.Security/System.Security.Cryptography.Xml/SignedInfo.cs

   1 //
   2 // SignedInfo.cs - SignedInfo implementation for XML Signature
   3 //
   4 // Author:
   5 //      Sebastien Pouliot  <sebastien@ximian.com>
   6 //
   7 // (C) 2002, 2003 Motus Technologies Inc. (http://www.motus.com)
   8 // (C) 2004 Novell (http://www.novell.com)
   9 //
  10
  11 //
  12 // Permission is hereby granted, free of charge, to any person obtaining
  13 // a copy of this software and associated documentation files (the
  14 // "Software"), to deal in the Software without restriction, including
  15 // without limitation the rights to use, copy, modify, merge, publish,
  16 // distribute, sublicense, and/or sell copies of the Software, and to
  17 // permit persons to whom the Software is furnished to do so, subject to
  18 // the following conditions:
  19 //
  20 // The above copyright notice and this permission notice shall be
  21 // included in all copies or substantial portions of the Software.
  22 //
  23 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  27 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  28 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  29 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  30 //
  31
  32 using System.Collections;
  33 using System.Xml;
  34
  35 namespace System.Security.Cryptography.Xml {
  36
  37         public class SignedInfo : ICollection, IEnumerable {
  38
  39                 private ArrayList references;
  40                 private string c14nMethod;
  41                 private string id;
  42                 private string signatureMethod;
  43                 private string signatureLength;
  44                 private XmlElement element;
  45
  46                 public SignedInfo()
  47                 {
  48                         references = new ArrayList ();
  49                         c14nMethod = "http://www.w3.org/TR/2001/REC-xml-c14n-20010315";
  50                 }
  51
  52                 public string CanonicalizationMethod {
  53                         get { return c14nMethod; }
  54                         set {
  55                                 c14nMethod = value;
  56                                 element = null;
  57                         }
  58                 }
  59
  60                 // documented as not supported (and throwing exception)
  61                 public int Count {
  62                         get { throw new NotSupportedException (); }
  63                 }
  64
  65                 public string Id {
  66                         get { return id; }
  67                         set {
  68                                 element = null;
  69                                 id = value;
  70                         }
  71                 }
  72
  73                 // documented as not supported (and throwing exception)
  74                 public bool IsReadOnly {
  75                         get { throw new NotSupportedException (); }
  76                 }
  77
  78                 // documented as not supported (and throwing exception)
  79                 public bool IsSynchronized {
  80                         get { throw new NotSupportedException (); }
  81                 }
  82
  83                 // Manipulating this array never affects GetXml() when
  84                 // LoadXml() was used.
  85                 // (Actually, there is no way to detect modification.)
  86                 public ArrayList References {
  87                         get { return references; }
  88                 }
  89
  90                 public string SignatureLength {
  91                         get { return signatureLength; }
  92                         set {
  93                                 element = null;
  94                                 signatureLength = value;
  95                         }
  96                 }
  97
  98                 public string SignatureMethod {
  99                         get { return signatureMethod; }
 100                         set {
 101                                 element = null;
 102                                 signatureMethod = value;
 103                         }
 104                 }
 105
 106                 // documented as not supported (and throwing exception)
 107                 public object SyncRoot {
 108                         get { throw new NotSupportedException (); }
 109                 }
 110
 111                 public void AddReference (Reference reference)
 112                 {
 113                         references.Add (reference);
 114                 }
 115
 116                 // documented as not supported (and throwing exception)
 117                 public void CopyTo (Array array, int index)
 118                 {
 119                         throw new NotSupportedException ();
 120                 }
 121
 122                 public IEnumerator GetEnumerator ()
 123                 {
 124                         return references.GetEnumerator ();
 125                 }
 126
 127                 public XmlElement GetXml ()
 128                 {
 129                         if (element != null)
 130                                 return element;
 131
 132                         if (signatureMethod == null)
 133                                 throw new CryptographicException ("SignatureMethod");
 134                         if (references.Count == 0)
 135                                 throw new CryptographicException ("References empty");
 136
 137                         XmlDocument document = new XmlDocument ();
 138                         XmlElement xel = document.CreateElement (XmlSignature.ElementNames.SignedInfo, XmlSignature.NamespaceURI);
 139                         if (id != null)
 140                                 xel.SetAttribute (XmlSignature.AttributeNames.Id, id);
 141
 142                         if (c14nMethod != null) {
 143                                 XmlElement c14n = document.CreateElement (XmlSignature.ElementNames.CanonicalizationMethod, XmlSignature.NamespaceURI);
 144                                 c14n.SetAttribute (XmlSignature.AttributeNames.Algorithm, c14nMethod);
 145                                 xel.AppendChild (c14n);
 146                         }
 147                         if (signatureMethod != null) {
 148                                 XmlElement sm = document.CreateElement (XmlSignature.ElementNames.SignatureMethod, XmlSignature.NamespaceURI);
 149                                 sm.SetAttribute (XmlSignature.AttributeNames.Algorithm, signatureMethod);
 150                                 if (signatureLength != null) {
 151                                         XmlElement hmac = document.CreateElement (XmlSignature.ElementNames.HMACOutputLength, XmlSignature.NamespaceURI);
 152                                         hmac.InnerText = signatureLength;
 153                                         sm.AppendChild (hmac);
 154                                 }
 155                                 xel.AppendChild (sm);
 156                         }
 157
 158                         // This check is only done when element is created here.
 159                         if (references.Count == 0)
 160                                 throw new CryptographicException ("At least one Reference element is required in SignedInfo.");
 161
 162                         // we add References afterward so we don't end up with extraneous
 163                         // xmlns="..." in each reference elements.
 164                         foreach (Reference r in references) {
 165                                 XmlNode xn = r.GetXml ();
 166                                 XmlNode newNode = document.ImportNode (xn, true);
 167                                 xel.AppendChild (newNode);
 168                         }
 169
 170                         return xel;
 171                 }
 172
 173                 private string GetAttribute (XmlElement xel, string attribute)
 174                 {
 175                         XmlAttribute xa = xel.Attributes [attribute];
 176                         return ((xa != null) ? xa.InnerText : null);
 177                 }
 178
 179                 public void LoadXml (XmlElement value)
 180                 {
 181                         if (value == null)
 182                                 throw new ArgumentNullException ("value");
 183
 184                         if ((value.LocalName != XmlSignature.ElementNames.SignedInfo) || (value.NamespaceURI != XmlSignature.NamespaceURI))
 185                                 throw new CryptographicException ();
 186
 187                         id = GetAttribute (value, XmlSignature.AttributeNames.Id);
 188                         c14nMethod = XmlSignature.GetAttributeFromElement (value, XmlSignature.AttributeNames.Algorithm, XmlSignature.ElementNames.CanonicalizationMethod);
 189
 190                         XmlElement sm = XmlSignature.GetChildElement (value, XmlSignature.ElementNames.SignatureMethod, XmlSignature.NamespaceURI);
 191                         if (sm != null) {
 192                                 signatureMethod = sm.GetAttribute (XmlSignature.AttributeNames.Algorithm);
 193                                 XmlElement length = XmlSignature.GetChildElement (sm, XmlSignature.ElementNames.HMACOutputLength, XmlSignature.NamespaceURI);
 194                                 if (length != null) {
 195                                         signatureLength = length.InnerText;
 196                                 }
 197                         }
 198
 199                         for (int i = 0; i < value.ChildNodes.Count; i++) {
 200                                 XmlNode n = value.ChildNodes [i];
 201                                 if (n.NodeType == XmlNodeType.Element &&
 202                                         n.LocalName == XmlSignature.ElementNames.Reference &&
 203                                         n.NamespaceURI == XmlSignature.NamespaceURI) {
 204                                         Reference r = new Reference ();
 205                                         r.LoadXml ((XmlElement) n);
 206                                         AddReference (r);
 207                                 }
 208                         }
 209                         element = value;
 210                 }
 211         }
 212 }