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--- ssh_sendmail_instead_of_login_shell [2022/11/12 01:56] – formatted code block jquah
+++ ssh_sendmail_instead_of_login_shell [2022/11/13 23:41] (current) – delete --- to be recreated with a more accurate name jquah
@@ Line 1: / Line 1: @@
-==== SSH session that runs sendmail instead of your login shell ====
-=== What? ===
-A wrapper for your local mail transfer agent (MTA) that initiates an SSH session when your SDF email address appears in the "From:" header.
-=== Why? ===
-You want to send email from your SDF address without running the risk that the receiving server will reject it due to a mismatch between the "From" header and your ISP's IP block, but the low volume of your outgoing mail cannot justify the cost of a VPM/VHOST/MetaARPA membership.
-=== Where? ===
-a *BSD, Linux, or WSL environment with a client that generates MIME-formatted mail (as expected by sendmail-compatible MTAs such as msmtp)
-=== How? ===
-  - Set up SSH public key authentication, if you have not already done so. This step can be omitted if you prefer to type your password for each outgoing mail.
-  - Save the wrapper script below somewhere in your $PATH. Change the value of $MTA to the mail transport agent that you would otherwise be using for outgoing mail, and of course change all email addresses to the ones you actually want to wrap.
-  - Configure your mail user agent (MUA) to call the wrapper script, rather than calling your MTA directly.
-<code>
-#!/usr/bin/env bash
-#
-# msmtp.wrap - bypass local in favor of remote sendmail,
-#              if certain headers are found
-Account0=me@sdf.org
-Account1=me@other-pubnix.net
-MTA=msmtp
-draft="$(mktemp -t sendmail.XXXXXX)"
-cat /dev/stdin > "$draft"
-sender="$(grep '^From:' "$draft" | head -n 1 | cut -d: -f2)"
-case "$sender" in
-    *me@sdf.org* )
-        sendmail="ssh $Account0 sendmail -t" ;;
-    *me@other-pubnix.net* )
-        sendmail="ssh $Account1 sendmail -t" ;;
-    * )
-        sendmail="$MTA $*" ;;
-esac
-< "$draft" $sendmail; status=$?
-rm -f "$draft"; exit $status
-</code>