[Xymon] xymonnet additional capability -- pause

[Shawn Heisey]

Over ten years ago, I asked on this list how I could get rid of the 
"incorrect pipelining message" logged by postfix every time the smtp, 
smtps, or submission tests are done.

https://lists.xymon.com/oldarchive/2010/11/msg00207.html

The fix that I claim worked (multiple send commands) was for a job I had 
at the time.  Now I am have a personal mail server (that also runs 
xymon) and that fix I mentioned so long ago is not working.

I tweaked the code to allow a "pause" action in protocols.cfg and after 
modifying protocols.cfg to utilize it, I have eliminated the "incorrect 
command pipelining" message in mail.log.  Here's the patch:

--- xymon-4.3.28/lib/netservices.c      2017-01-05 19:00:06.000000000 -0700
+++ pause-xymon-4.3.28/lib/netservices.c        2021-05-29 
12:51:09.717461323 -0600
@@ -259,6 +259,10 @@
                                 }
                         }
                 }
+               else if (strncmp(l, "pause ", 6) == 0) {
+                       int pausetime = atoi(skipwhitespace(l+5));
+                       sleep(pausetime);
+               }
         }

         if (fd) stackfclose(fd);

Here's the new definitions I created in protocols.cfg:

[smtp]
    pause 2
    send "ehlo xymonnet.localdomain\r\n"
    pause 2
    send "mail\r\n"
    pause 2
    send "quit\r\n"
    expect "220"
    options banner
    port 25

[smtps]
    pause 2
    send "ehlo xymonnet.localdomain\r\n"
    pause 2
    send "mail\r\n"
    pause 2
    send "quit\r\n"
    expect "220"
    options ssl,banner
#  No default port-number assignment for smtps - nonstandard according 
to IANA

[submission|msa]
    pause 2
    send "ehlo xymonnet.localdomain\r\n"
    pause 2
    send "mail\r\n"
    pause 2
    send "quit\r\n"
    expect "220"
    options banner
    port 587


And this is now what I see in mail.log (testing smtps and submission:

May 29 13:51:15 bilbo postfix/submission/smtpd[16324]: connect from 
bilbo.elyograg.org[172.31.8.104]
May 29 13:51:15 bilbo postfix/submission/smtpd[16324]: disconnect from 
bilbo.elyograg.org[172.31.8.104] quit=1 commands=1
May 29 13:51:15 bilbo postfix/smtps/smtpd[16325]: connect from 
bilbo.elyograg.org[172.31.8.104]
May 29 13:51:15 bilbo postfix/smtps/smtpd[16325]: disconnect from 
bilbo.elyograg.org[172.31.8.104] quit=1 commands=1

Interesting thing here is that it's not actually pausing.  Which 
probably means that I implemented it incorrectly.  My training on C is 
ancient and I'm very rusty.  But even though it doesn't pause, the error 
is gone, simply because each smtp command is now sent in a separate 
packet, which appears to *sometimes* be enough "delay" for postfix to 
not complain about pipelining.  What happens now is occasionally I will 
get a yellow status on smtps with the xymon UI saying "Service smtps on 
bilbo.elyograg.org is not OK : Unexpected service response".

So I think what I will do before submitting a patch is implement a 
"null" action (which will do nothing) as well as a "pause" action, and 
get some help from the real C developers here for making "pause" behave 
as advertised.  Can somebody point me to some instructions on properly 
creating and submitting a patch?  Also, if I could get some info on any 
other files I need to modify (man pages, readme files, etc), I would 
really appreciate it.

Thanks,
Shawn