public static Email ParseEmail(string data)
{
var email = new Email();
bool isHeader = true;
using (var reader = new StringReader(data))
{
string line;
while ((line = reader.ReadLine()) != null)
{
if (isHeader)
{
if (line == string.Empty)
{
isHeader = false;
continue;
}
email.HeaderLines.Add(line);
}
else
{
email.BodyLines.Add(line);
}
}
}
email.Body = string.Join(Environment.NewLine, email.BodyLines);
email.Headers = string.Join(Environment.NewLine, email.HeaderLines) + Environment.NewLine;
return email;
}
string GenerateSignature(Email email, params string[] signHeaders)
{
// timestamp - seconds since 00:00:00 on January 1, 1970 UTC
TimeSpan t = DateTime.Now.ToUniversalTime() -
DateTime.SpecifyKind(DateTime.Parse("00:00:00 January 1, 1970"), DateTimeKind.Utc);
var signatureValue = new StringBuilder();
signatureValue.Append("v=1; ");
signatureValue.Append("a=rsa-sha256; ");
// Canonicalization
signatureValue.Append("c=");
signatureValue.Append(this.HeaderCanonicalization.ToString().ToLower());
signatureValue.Append('/');
signatureValue.Append(this.BodyCanonicalization.ToString().ToLower());
signatureValue.Append("; ");
signatureValue.Append("q=dns/txt; ");
// signing domain
signatureValue.Append("d=");
signatureValue.Append(this.Domain);
signatureValue.Append("; ");
// selector
signatureValue.Append("s=");
signatureValue.Append(this.Selector);
signatureValue.Append("; ");
// time sent
signatureValue.Append("t=");
signatureValue.Append((int)t.TotalSeconds);
signatureValue.Append("; ");
// hash of body
signatureValue.Append("bh=");
signatureValue.Append(SignBody(Canonicalization.CanonicalizationBody(email.Body, this.BodyCanonicalization)));
signatureValue.Append("; ");
// headers to be signed
signatureValue.Append("h=");
//sb.Append(string.Join(":", headers));
foreach (var header in signHeaders)
{
signatureValue.Append(header);
signatureValue.Append(':');
}
signatureValue.Length--;
signatureValue.Append("; ");
signatureValue.Append("b=");
Console.WriteLine();
Console.WriteLine("---- start sig ----");
Console.WriteLine(signatureValue);
Console.WriteLine("---- start sig ----");
var catHeaders = new StringBuilder();
catHeaders.Append(Canonicalization.CanonicalizationHeaders(email.Headers, this.HeaderCanonicalization));
//foreach (var header in signHeaders)
//{
// catHeaders.Append(header.ToLower());
// catHeaders.Append(':');
// catHeaders.AppendLine(headers[header]);
//}
catHeaders.Append("dkim-signature:");
catHeaders.Append(signatureValue);
Console.WriteLine("---- can sig ----");
Console.WriteLine(catHeaders);
Console.WriteLine("---- can end ----");
using (TextReader reader = new StringReader(this.PrivateKey))
{
var r = new PemReader(reader);
var o = (AsymmetricCipherKeyPair)r.ReadObject();
byte[] plaintext = this.Encoding.GetBytes(catHeaders.ToString());
ISigner sig = SignerUtilities.GetSigner("SHA256WithRSAEncryption");
sig.Init(true, o.Private);
sig.BlockUpdate(plaintext, 0, plaintext.Length);
byte[] signature = sig.GenerateSignature();
signatureValue.Append(Convert.ToBase64String(signature));
}
return signatureValue.ToString();
}
