How to sign gmail email with digital signature?

Question

I have my personal digital signature on the special card and the according reader. How can I sign an email (sending it with gmail) with this signature? I am on the latest OSX and use Google Chrome (but can use Windows 7, if it is really required).

Solution

Gmail doesn't have built-in support for encrypting and signing the emails, so there are others options you could try:

Note: There is an ongoing project for a Chrome extension named "End-to-End" which provides encryption, decryption and digital signature. It is not open for general use yet.

1. Use add-ons for Google Chrome i.e. EnigmaGPG, Mymail-crypt etc.

2. You can use PGP (Pretty Good Privacy). It works on public-key cryptography. First you have to generate a public-private key pair via GPG (so that others would be able to send you encrypted messages). You can sign the messages manually and make it armoured to send (provided that you have your recipient's correspondent public key to cipher) or in Mac OS use the gpgtools which contains everything to secure your communication.

3. There are email clients like Thunderbird which has the support for PGP via enigmail or openPGP.

Visit this site for the "End-to-End Chrome" extension.

Comments

[Ramhound]

You can't; Google does not support this;

[LA_]

I don't want just to encrypt the message, I should sign the message with the signature I have (in order to communicate with the government), so PGP wouldn't work here.

[skush]

I think i misunderstood your question regarding the card. Anyway as far as i know, to be able to sign/encrypt messages using your own card you have to have a digital certificate to endorse the ownership of your key-pair. The Card provider might provide an extension or kind of add-ons to the email client like Apple Mail, Thunderbird etc. in order to sign/encrypt the messages.

[maxheld]

just fyi; the Google Suite version of Gmail does appear to support S/MIME signing support.google.com/a/answer/6374496?hl=en