I'm trying to get some exclusions into our sendmail regular expression for the K command. The following configuration & regex works:
LOCAL_CONFIG
#
Kcheckaddress regex -a@MATCH
[a-zA-Z_0-9.-]+<@[a-zA-Z_0-9-]+?\.+[a-zA-Z_0-9.-]+?\.(us|info|to|br|bid|cn|ru)
LOCAL_RULESETS
SLocal_check_mail
# check address against various regex checks
R$* $: $>Parse0 $>3 $1
R$+ $: $(checkaddress $1 $)
R@MATCH $#error $: "553 Your Domain is Blocked for Unsolicited Mail"
So we are blocking anything@subdomain.domain.us but not anything@domain.us. I'd like to add exclusions for cities and schools so to allow user@ci.somedomain.us and user@subdomain.[state].us. (note that [state] means 1 of the 50 states including DC).
This regex with negative lookahead syntax is not working (using CA for California as a test):
(?!.*\@ci\..+?\.us$)(?!.*\@*\..+?\.ca.us$)([a-zA-Z_0-9.-]+@[a-zA-Z_0-9-]+?\.+[a-zA-Z_0-9.-]+?\.(us)$)
I get this error:
sendmail -bt
/etc/mail/sendmail.cf: line 199: pattern-compile-error: Invalid preceding regular expression
I'm pretty sure that sendmail's R & K commands do not support negative look-aheads. So if anyone can help re-write the regex in a sed-friendly format I'd be grateful! Here is a link to K command switches. Any suggestions on how to get the negative lookahead to work in sendmail?