public static Email Parse([NotNull] this MailMessage message)
{
if (message == null)
{
throw new ArgumentNullException("message");
}
return(Email.Parse(message.GetText()));
}
public string SignEmail(string message)
{
// get email content and generate initial signature
var email = Email.Parse(message);
email.Headers.Add(SignatureKey, new EmailHeader {
Key = SignatureKey, Value = this.GenerateDkimHeaderValue(email)
});
email.Headers[SignatureKey].Value += this.GenerateSignature(email);
return(SignatureKey + ':' + email.Headers[SignatureKey].Value + Email.NewLine + email.Raw);
}
//public static void PrependHeader([NotNull]this MailMessage message, bool useEnvelope, [NotNull]string key, [NotNull]string value)
//{
// if (message == null)
// {
// throw new ArgumentNullException("message");
// }
// var msg = MsgField.GetValue(message);
// var headers = (NameValueCollection)HeadersProperty.GetValue(msg, null);
// if (useEnvelope)
// {
// headers.Prepend(key, value);
// }
// else
// {
// message.Headers.Prepend(key, value);
// }
//}
/// <summary>
/// Indicates if the library is able to sign the given MailMessage
/// </summary>
/// <param name="message"></param>
/// <returns></returns>
public static bool CanSign([NotNull] this MailMessage message)
{
// the signing process for mail messages involves 'sending' it multiple times
// to an in memory stream instead of an SMTP server. Unfortunately every time
// the message is sent the boundary header value is regenerated meaning the signing is broken.
// Boundaries are used with mulit part emails e.g. adding attachments or including a text and html version
if (message == null)
{
throw new ArgumentNullException("message");
}
var email = Email.Parse(message.GetText());
return(CanSign(email));
}
public static MailMessage DkimSign([NotNull] this MailMessage message, DkimSigner signer)
{
if (message == null)
{
throw new ArgumentNullException("message");
}
if (signer == null)
{
throw new ArgumentNullException("signer");
}
message.BodyEncoding = signer.Encoding;
message.SubjectEncoding = signer.Encoding;
message.HeadersEncoding = signer.Encoding;
// get email content and generate initial signature
var email = Email.Parse(message.GetText());
if (!CanSign(email))
{
throw new InvalidOperationException("Unable to Domain Key sign the message");
}
var value = signer.GenerateDkimHeaderValue(email);
// signature value get formatted so add dummy signature value then remove it
message.Headers.Prepend(DkimSigner.SignatureKey, value + new string('0', 70));
email = message.Parse();
var formattedSig = email.Headers[DkimSigner.SignatureKey].Value;
email.Headers[DkimSigner.SignatureKey].Value = formattedSig.Substring(0, formattedSig.Length - 70);
// sign email
value += signer.GenerateSignature(email);
message.Headers.Set(DkimSigner.SignatureKey, value);
return(message);
}
