Salesforce SPF and now DKIM support

Salesforce has published a SPF record for sending emails from Salesforce for years and with the Spring ’15 release, they will provide the option to sign with DKIM.
The SPF record is straight forward, include:_spf.salesforce.com which includes _spf.google.com, _spfblock.salesforce.com, several IP address blocks, mx, and ends with a SoftFail ~all.
Salesforce Knowledge Article Number: 000006347 goes in-depth with information regarding their SPF Record.

With the Spring ’15 Release, Salesforce offers the ability sign outbound emails with DomainKeys (DKIM).

DKIM signing of outbound email is available for Enterprise, Unlimited, and Developer Editions.  Salesforce recommends that you add the public key to your DNS before activating DKIM signing.  There is a limit of 1 DKIM key per domain and Salesforce gives you the option to domain match and sign emails for the domain only, subdomain only, or domain and subdomains.  More information about Salesforce DKIM signing can be found within their Spring 15’ Release Notes.
The ability to sign with non-Salesforce DKIM keys means that Salesforce users now have the option to use DMARC. Prior to this change all mail was authenticated as coming from Salesforce, which is perfectly acceptable and how authentication works. The ability to sign with the users’ DKIM key and domain means large Salesforce users are now able to track authentication failures or publish DMARC policy requests.

Related Posts

Troubleshooting tools

There have been a number of comments on my post about Hotmail moving to SPF authentication having to do with troubleshooting authentication failures. I have been helping clients troubleshoot these issues, and am able to take on new clients to solve authentication problems. Contact me for more information.
Of course, many of these issues can be solved with access to the right tools. Steve’s been working on a number of tools that may help the troubleshooting process and we’ve recently launched them on Emailstuff.org. The website itself contains a number of DNS and data related tools we use for investigations and thought we’d share with the public at large.
One of the really useful tools is the SPF record expander. Plug in any domain, like google.com, and see what IP addresses they authorize to send mail.

Read More

Office365 checking DMARC on the inbound

According to a recent blog post, Office365 is starting to evaluate incoming messages for DMARC. I talked a little bit about DMARC in April when Yahoo started publishing a p=reject message.

Read More

How long is your DKIM key?

While we were at M3AAWG, Wired published an article talking about how simple it was to crack DKIM keys. I didn’t post about it at the time because it didn’t really seem like news. DKIM keys smaller than 1024 are vulnerable and not secure and the DKIM spec does not recommend using keys smaller than 1024. When I asked the DKIM-people-who-would-know they did tell me that the news was that the keys had been cracked and used in the wild to spoof email.
Fair enough.
If you are signing with DKIM, use a key 1024 or longer. Anything shorter and your risk having the key cracked and your mail fraudulently signed.
This morning M3AAWG published recommendations on keeping DKIM keys secure.

Read More