/// <summary>
/// Construct a GroupSerializable object from a Group object.
/// </summary>
/// <param name="group">The Group object being serialized.</param>
public GroupSerializable(Group group)
{
if (this.InRecommendedGroup(group.GroupName))
{
this.type = "named";
this.name = group.GroupName;
this.sgDesc = null;
}
else if (group.Type == GroupType.ECC)
{
this.type = "ec";
this.name = null;
this.sgDesc = null;
}
else if (group.Type == GroupType.Subgroup)
{
this.type = "sg";
this.sgDesc = new SubgroupGroupSerializable((SubgroupGroup)group);
this.name = null;
}
else
{
throw new UProveSerializationException("Invalid GroupConstruction");
}
return;
}
public static GroupElement CreateGroupElement(Group Gq, string value)
{
if (Gq is SubgroupGroup)
{
return Gq.CreateGroupElement(HexToBytes(value));
}
else
{
ECGroup ecGq = Gq as ECGroup;
string[] point = value.Split(',');
return ecGq.CreateGroupElement(HexToBytes(point[0]), HexToBytes(point[1]));
}
}
/// <summary>
/// Private constructor - takes and sets all fields.
/// </summary>
/// <param name="Gq">The group</param>
/// <param name="gd">The device generator</param>
/// <param name="Zq">The Field associated to the group <c>Gq</c></param>
/// <param name="xd">The xd.</param>
/// <param name="preGenWdPrime">The pre gen wd prime.</param>
VirtualDevice(Group Gq, GroupElement gd, FieldZq Zq, FieldZqElement xd, FieldZqElement preGenWdPrime)
{
if (xd != null && !Zq.IsElement(xd))
{
throw new ArgumentException("xd is not a valid Zq element");
}
this.Gd = gd;
this.Gq = Gq;
this.Zq = Zq;
this.xd = xd ?? this.Zq.GetRandomElement(true); // assign xd a random value if null
this.wdPrime = preGenWdPrime;
this.hd = this.Gd.Exponentiate(this.xd);
}
/// <summary>
/// Convert a base64 string to a GroupElement[] using a specific Group object.
/// </summary>
/// <param name="encodedElements">The encoded string to convert.</param>
/// <param name="group">The group object to use.</param>
/// <returns>The converted object.</returns>
public static GroupElement[] ToGroupElementArray(this String[] encodedElements, Group group)
{
if (encodedElements == null) return null;
if (group == null) throw new ArgumentNullException("group");
GroupElement[] groupElements = new GroupElement[encodedElements.Length];
for (int i = 0; i < encodedElements.Length; i++)
{
groupElements[i] = encodedElements[i].ToGroupElement(group);
}
return groupElements;
}
/// <summary>
/// Convert a base64 string to a GroupElement using a specific Group object.
/// </summary>
/// <param name="encodedString">The encoded string to convert.</param>
/// <param name="group">The group object to use.</param>
/// <returns>The converted object.</returns>
public static GroupElement ToGroupElement(this String encodedString, Group group)
{
if (encodedString == null) return null;
if (group == null) throw new ArgumentNullException("group");
return group.CreateGroupElement(encodedString.ToByteArray());
}
/// <summary>
/// Hash a Group.
/// </summary>
/// <param name="value">A group to be hashed.</param>
public void Hash(Group value)
{
value.UpdateHash(this);
}
/// <summary>
/// Create the group element associated with a scope.
/// </summary>
public static GroupElement GenerateScopeElement(Group Gq, byte[] scope)
{
int counter;
return Gq.DeriveElement(scope, ScopeElementIndex, out counter);
}