Relay rules for sender are not honored in some cases

[lucagasparini]

When configuring multiple relay rules for different senders but using the same host and port, only the first configured one in chronological order is always used.

Steps to reproduce

• creates two relay rules for senders with the same host and port (in chronological order first for user1 and then for user2)
  for example:

runagent -m mail1 podman exec -ti postfix ash -l
rl1:/etc/postfix# sqlite3 /srv/pcdb.sqlite
sqlite> select * from relayrules;

sender|user1@lg.nethserver.net|smtp|rl2.demo.neth.eu|587|encrypt|relay1|******|1
sender|user2@lg.nethserver.net|smtp|rl2.demo.neth.eu|587|encrypt|relay2|******|1

• send an email with from user2@lg.nethserver.net

Expected behavior

• the email is sent via Relay Host with sasl_username=user2 authentication

Actual behavior

• the email is sent via Relay Host with sasl_username=user1 authentication

from the maillog of the mail server that sends:

rl1 postfix/smtpd[1112149]: 51E56C011401: client=cluster-localnode[10.5.4.1], sasl_method=LOGIN, sasl_username=user2
rl1 postfix/cleanup[1112151]: 51E56C011401: message-id=<1592469657.17.1746000737282@webtop>
rl1 postfix/qmgr[1110131]: 51E56C011401: from=<user2@lg.nethserver.net>, size=1397, nrcpt=1 (queue active)
postfix/smtp[1112154]: 51E56C011401: to=<test@test.net>, relay=rl2.demo.neth.eu[147.182.130.69]:587, delay=2.4, delays=0.43/0.03/1.1/0.79, dsn=2.0.0, status=sent (250 2.0.0 Ok: queued as EA764F801C40)

from maillog host rl2.demo.neth.eu

rl2 postfix/smtpd[2523490]: EA764F801C40: client=rl1.lg.nethserver.net[128.199.41.194], sasl_method=LOGIN, sasl_username=relay1

I think the problem is in the query used here:
https://github.com/NethServer/ns8-mail/blob/main/postfix/etc/postfix/relaysender_transport.cf

Components

Mail 1.6.2

See also

• Discussion https://mattermost.nethesis.it/nethesis/pl/y6dskrosd7gcjkj6obfuoe7ruc
• https://community.nethserver.org/t/single-relay-for-account-does-not-work-but-in-a-strange-way/25575

---

Many thanks to Emiliano Vavassori (Ref: #189033)

[DavidePrincipi]

In Testing, Mail 1.7.0-dev.1

Test case

Check the bug is not reproducible

[lucagasparini]

Test case: VERIFIED