/// <summary>
/// Декодируем из байтового массива в формате ASN1
/// </summary>
/// <param name="baAsn1">Байтовый массив в формате ASN1</param>
/// <returns>Текстовое представление пакета ASN1</returns>
public string DecodeFromAsn1(byte[] baAsn1)
{
var memoryStream = new MemoryStream(baAsn1);
using (var berReader = new BerReader(memoryStream))
{
//Формируем маркант
try
{
var node = berReader.ReadToEnd().ChildNodes[0];
string result = "";
foreach (var childNode in node.ChildNodes)
{
result = berReader.PrintStructure(childNode, result, 1, true);
}
Version = (int)node.ChildNodes[0].ReadContentAsBigInteger();
SessionKey = node.ChildNodes[1].RawValue;
IV = node.ChildNodes[2].RawValue;
PublicKey = node.ChildNodes[3].RawValue;
return(result);
}
catch (Exception e)
{
throw new Exception("Invalid markant format", e);
}
}
}
/// <summary>
/// Формирует строка со структурным представлением байтового массива в формате ASN1
/// </summary>
/// <param name="baAsn1">Байтовый массив в формате ASN1</param>
/// <returns>Строка с текстовым представлением байтового массива в формате ASN1</returns>
public static string PrintFromAsn1(byte[] baAsn1)
{
var memoryStream = new MemoryStream(baAsn1);
using (var berReader = new BerReader(memoryStream))
{
//Формируем текстовое представление марканта
try
{
var node = berReader.ReadToEnd().ChildNodes[0];
string result = "ASN1:";
foreach (var childNode in node.ChildNodes)
{
result = berReader.PrintStructure(childNode, result, 1, true);
}
return(result);
}
catch (Exception e)
{
throw new Exception("Invalid ASN format", e);
}
}
}
/// <summary>
/// Печатает ASN.1 структуру
/// </summary>
/// <param name="reader">Объект BerReader</param>
/// <param name="node">Узел дерева</param>
/// <param name="relativeResult">Предыдущий результат работы данного метода</param>
/// <param name="depth">Глубина вложенности</param>
/// <param name="dumpValues">Печатать значения</param>
/// <returns>Структура ASN.1 представленная в виде строки</returns>
internal static string PrintStructure(this BerReader reader, InternalNode node, string relativeResult, int depth, bool dumpValues)
{
var offsetAndLength = String.Format("({0},{1})",
node.StartPosition.ToString(CultureInfo.InvariantCulture),
node.Length.ToString(CultureInfo.InvariantCulture));
var structure = String.Format("{0} {1}",
offsetAndLength,
(node.Identifier.Class == Asn1Class.ContextSpecific)
? String.Format("{0} ({1})", node.Identifier.Class, (int)node.Identifier.Tag)
: node.Identifier.Tag.ToString());
if (dumpValues)
{
if (node.NodeType == Asn1NodeType.Primitive)
{
string stringValue;
node.RawValue = reader.ReadContentAsBuffer(node);
switch (node.Identifier.Tag)
{
case Asn1Type.ObjectIdentifier:
stringValue = node.ReadContentAsObjectIdentifier();
break;
case Asn1Type.PrintableString:
case Asn1Type.Ia5String:
case Asn1Type.Utf8String:
stringValue = node.ReadContentAsString();
break;
case Asn1Type.GeneralizedTime:
case Asn1Type.UtcTime:
stringValue = node.ReadConventAsDateTimeOffset().ToString();
break;
case Asn1Type.Integer:
stringValue = node.ReadContentAsBigInteger().ToString();
break;
case Asn1Type.Boolean:
stringValue = node.ReadContentAsBoolean().ToString();
break;
default:
stringValue = node.RawValue.ToHexString();
break;
}
structure = string.Format("{0} : {1}", structure, stringValue);
}
}
for (int i = 0; i < depth; i++)
{
structure = "\t" + structure;
}
string res = relativeResult + Environment.NewLine + structure;
var innerdepth = (node.ChildNodes.Count > 0) ? depth + 1 : depth;
foreach (var innerNode in node.ChildNodes)
{
res = reader.PrintStructure(innerNode, res, innerdepth, dumpValues);
}
return(res);
}
/// <summary>
/// Prints structure of given ASN.1 node. Node should be the result of ReadToEnd method called before.
/// </summary>
/// <param name="reader">Extended object</param>
/// <param name="node">Node to print structure of.</param>
/// <param name="relativeResult">Relative result of this method. Used when iterating through the structure to build on top of previous results of this method.</param>
/// <param name="depth">Actual depth of parser.</param>
/// <param name="dumpValues">Flag indicating if values should be printed out.</param>
/// <returns>Structure of ASN.1 node as string.</returns>
internal static string PrintStructure(this BerReader reader, InternalNode node, string relativeResult, int depth, bool dumpValues)
{
// print offset in source stream and length of ASN.1 node
var offsetAndLength = String.Format("({0},{1})",
node.StartPosition.ToString(CultureInfo.InvariantCulture),
node.Length.ToString(CultureInfo.InvariantCulture));
// append tag name
var structure = String.Format("{0} {1}",
offsetAndLength,
(node.Identifier.Class == Asn1Class.ContextSpecific)
? String.Format("{0} ({1})", node.Identifier.Class, (int)node.Identifier.Tag)
: node.Identifier.Tag.ToString());
// append value of ASN.1 node
if (dumpValues)
{
if (node.NodeType == Asn1NodeType.Primitive)
{
string stringValue;
node.RawValue = reader.ReadContentAsBuffer(node);
switch (node.Identifier.Tag)
{
case Asn1Type.ObjectIdentifier:
stringValue = node.ReadContentAsObjectIdentifier();
break;
case Asn1Type.PrintableString:
case Asn1Type.Ia5String:
case Asn1Type.Utf8String:
stringValue = node.ReadContentAsString();
break;
case Asn1Type.GeneralizedTime:
case Asn1Type.UtcTime:
stringValue = node.ReadConventAsDateTimeOffset().ToString();
break;
case Asn1Type.Integer:
stringValue = node.ReadContentAsBigInteger().ToString();
break;
case Asn1Type.Boolean:
stringValue = node.ReadContentAsBoolean().ToString();
break;
default:
stringValue = node.RawValue.ToHexString();
break;
}
structure = string.Format("{0} : {1}", structure, stringValue);
}
}
// apply depth
for (int i = 0; i < depth; i++)
{
structure = "\t" + structure;
}
// append new line
string res = relativeResult + Environment.NewLine + structure;
// count new depth if node has children
var innerdepth = (node.ChildNodes.Count > 0) ? depth + 1 : depth;
// recursively go through children and print structure of them
foreach (var innerNode in node.ChildNodes)
{
res = reader.PrintStructure(innerNode, res, innerdepth, dumpValues);
}
// return result
return(res);
}