Using msmtp parameters

[Dominik Wild]

The cli parameter checks introduced in 1.2.5 are quite strict. We use certain parameters which are specific to msmtp and those parameters obviously don't pass the checks. Therefore an option to bypass the checks would be helpful.

[Daniel D. (cshoredaniel-deactivatedaccount)]

Hi. Thanks for the report. (Wow! Someone other than me uses the project!)

Would you rather have support for all the parameters msmtp can take, or just a bypass?

[Dominik Wild (wilddom)]

Well, I don't know the exact reason why you implemented the checks. Without the checks the plain and usually consice error message from msmtp was written to the queue folder. After updating the scripts it took me quite a while to figure out what's going on, because of the generic error message ("Failed to create .msmtp file"). Therefore I'm not sure it makes sense to implement checks for all of the command line options of msmtp, there are so many of them. Maybe it would be easier to just pass the error messages from msmtp and skip the checks.

[Daniel D. (cshoredaniel-deactivatedaccount)]

Sorry for the long silence. Life's been busy. The issue is that I am concerned about the security issues implicit in using raw command lines which may be partially supplied by the user (e.g. via parameters to the sendmail command). In fact I would rather make it harder to pass unverified command lines rather than easier (in particular I'm finding it difficult to figure out how allow valid email addresses but only valid (syntax-wise) email addresses where an email address is allowed).

In fact given the low usage rate of the project and my concerns about the overall security of the approach I'm still debating whether to keep this project alive or not.

The other big issue is with the fact that non-root daemons can issues with sending mail, particularly when using SELinux or similar mechanisms to restrict the daemon or cronjob that calls sendmail.

I think these issues are best resolved by doing something like the old 'nullmailer' approach that used to exist, but I'm not sure of whether it's really worth the effort of building that.