The current sSMTP configuration could use some improvement when needing to configure SMTP AUTH. The sSMTP man page does mention -au/-ap/-am. However, such options do not provide for compatibility applications that do not allow the "sendmail" invocation to be modified. Therefore, in many installations it may be desirable to establish a system-wide authentication setting. sSMTP *does* support this in the AuthUser/AuthPass/AuthMethod settings, but you would only learn of these by examining the source code; there are not mentioned in either the man page nor the configuration file. I recommend minimally adding an example to the Gentoo sSMTP default/example configuration file. Using AuthUser/AuthPass/AuthMethod does have one immediate drawback with the current Gentoo packaging; the password for AuthPass is saved as plaintext in the sSMTP configuration file, which is world-readable. I solved this problem on my system by creating a new group "smtp". I then restricted the permissions on my ssmtp.conf file to be read-write by the root user, and read-only by the smtp group, and not readable to the world. Finally, I changed the group ownership of the ssmtp executable to be the smtp group and may the binary setgid, allowing anyone to execute the ssmtp ("sendmail") executable, temporarily pick up the smtp group membership so that it can read the authentication information from the sSMTP configuration file. I'd recommend that Gentoo do something similar.
Sorry but this is something that should be fixed in upstream (imho). If the 'feature' is both poor designed and not documented anywhere is again an upstream task to solve this problems. Contact upstream first, thats the best way. Cheers, Ferdy
