[Ext][Thunderbird] DKIM Signature Verifier

[lieser]

Verifies the DKIM Signatures of e-mails.

More info about the Add-on at its homepage at https://github.com/lieser/dkim_verifier/wiki or on AMO.

Download

The add-on can be downloaded from https://addons.mozilla.org/addon/dkim-verifier/ or https://github.com/lieser/dkim_verifier/releases. The source code is available at https://github.com/lieser/dkim_verifier

Support / Bug report

Support is given at https://github.com/lieser/dkim_verifier/issues, in this thread or by e-mail to lieser+dkim@posteo.net (in English or German).

The preferred way to report bugs is by creating an issue at https://github.com/lieser/dkim_verifier/issues.

If debug information is needed, enabling of debugging in the advanced options is sufficient in most cases. Details about the available debug options can be found here.

Screenshots


More screenshots at Add-on home page at AMO.

[Jan.]

Great add-on!

I do have one suggestion: cache the DKIM results so it doesn't check every time you click on an email already processed by the add-on ? It should be an option I think.

[lieser]

I have added you suggestion in version 0.5.0, which is currently under review. It is off by default, so you will have to enable it after installing the new version.
If you click the "Other Actions" button, there is a entry to reverify the Signature if needed.

[hackery]

I'm not familiar with the extension API, so I don't know if this is practical, but could DKIM Verifier do something like the spam system, where on a failure, remote content is not loaded, and perhaps links are disabled (though I'm not sure if there's actually a way for the spam system to do the latter).

[lieser]

I'm not familiar with the extension API, so I don't know if this is practical, but could DKIM Verifier do something like the spam system, where on a failure, remote content is not loaded, and perhaps links are disabled (though I'm not sure if there's actually a way for the spam system to do the latter).

Disabling the loading of remote content should be already disabled by default (even for non spam messages). More about it at http://kb.mozillazine.org/Privacy_basic ... derbird%29.
If you are talking about temporary disabling the exceptions saved in the address book, I don't think there is an easy way to do it.

Disabling the links in plain text messages is probably not possible. In HTML messages it's probably possible by altering the body. More at http://kb.mozillazine.org/Links_generated_automatically.
But as you first have to click them before something happens, I don't see why they should be disabled in the first place.

[Zine2013]

A question: Can the DKIM Verifier use the default DNS server (i.e. the one configured in the OS and used by Thunderbird)? E.g. when the "DNS Nameserver" field in the "DNS Verifier Options" is left empty.

That would be useful:
- for people using the OS default DNS service (instead of GoogleDNS, etc.)
- if one wants to configure their DNS service IP in one place (i.e. OS), instead of additionally in the DKIM Verifier (which may be forgotten after a while)

Thanks in advance for your reply.

[lieser]

A question: Can the DKIM Verifier use the default DNS server (i.e. the one configured in the OS and used by Thunderbird)? E.g. when the "DNS Nameserver" field in the "DNS Verifier Options" is left empty.

That would be useful:
- for people using the OS default DNS service (instead of GoogleDNS, etc.)
- if one wants to configure their DNS service IP in one place (i.e. OS), instead of additionally in the DKIM Verifier (which may be forgotten after a while)

Thanks in advance for your reply.

I added an option for this in version 0.5.1 (enabled by default). The nameservers in the add-on options will be used as fallback, but you can also left the field empty if you don't want this.
Tested it with Windows and Linux. Don't know if it works also with Mac, as i don't have one to test it.
If you need it also to work with Mac, could you test if it works before I submit the new version to AMO?
To test it you can get the prerelease version from https://github.com/lieser/dkim_verifier (unpacked), or I could sent you a packed version via e-mail (just sent me on to dkim.verifier.addon@gmail.com so I have your address).

[Zine2013]

I added an option for this in version 0.5.1 (enabled by default). The nameservers in the add-on options will be used as fallback, but you can also left the field empty if you don't want this.
Tested it with Windows and Linux. Don't know if it works also with Mac, as i don't have one to test it.
If you need it also to work with Mac, could you test if it works before I submit the new version to AMO?
To test it you can get the prerelease version from https://github.com/lieser/dkim_verifier (unpacked), or I could sent you a packed version via e-mail (just sent me on to dkim.verifier.addon@gmail.com so I have your address).

Thank you very much for the update!
Unfortunately, I don't have a Mac either. So, volunteers, feel free to step forward.

[lieser]

Thank you very much for the update!
Unfortunately, I don't have a Mac either. So, volunteers, feel free to step forward.

I have just submitted the new version. Review is probably completed within the next week. Or you can already download it unreviewed from https://addons.mozilla.org/addon/dkim-verifier/versions.

[Zine2013]

Just a question from someone who doesn't know much about Thunderbird system architecture: Where do the verification results get saved if the "Save result of the verification" option is activated? In the MSF file of the respective folder?

(Background is the curiosity to know how evaluation results could possibly be lost, making a re-evaluation necessary with that option active. E.g. by hitting the "Rebuild Folder" button in the folder properties to rebuild the MSF file, thereby removing the evaluation results, etc. This question is out of curiousity only, not a change proposal in any way.)

[lieser]

Just a question from someone who doesn't know much about Thunderbird system architecture: Where do the verification results get saved if the "Save result of the verification" option is activated? In the MSF file of the respective folder?

(Background is the curiosity to know how evaluation results could possibly be lost, making a re-evaluation necessary with that option active. E.g. by hitting the "Rebuild Folder" button in the folder properties to rebuild the MSF file, thereby removing the evaluation results, etc. This question is out of curiousity only, not a change proposal in any way.)

Yes, currently it should be saved in the .msf files.
But for me the saved results are not lost if I click "Repair Folder" (at least if it wasn't broken in the first place), only if I delete the .msf file.

[Axel Grude]

How do I set up DKIM to send from Thunderbird (POP3)? I have looked at the Wikipedia article, my gmail settings and googled a bit but didn't come up with anything useful.

[lieser]

How do I set up DKIM to send from Thunderbird (POP3)? I have looked at the Wikipedia article, my gmail settings and googled a bit but didn't come up with anything useful.

This add-on only supports the verification of DKIM signatures, not the signing of e-mails. So if you want to sign outgoing e-mail, the e-mail server will have to do this.
In case of Gmail, outgoing e-mails are signed automatically, there is no option for this. Note that if you sent an e-mail to your own address, it will not be signed. So if you want to test this, send the e-mail to another address.