github-com-docker-mailserver/docker-mailserver
1
0
Fork 0
mirror of https://github.com/docker-mailserver/docker-mailserver.git synced 2024-01-19 02:48:50 +00:00
Code Issues Projects Releases Wiki Activity

Postfix: add smtpd_data_restrictions = reject_unauth_pipelining (#3744)

Browse source 
* add `smtpd_data_restrictions = reject_unauth_pipelining`

* fix: Skip restriction if trusted

* add changelog entry

* revert change to `postfix-amavis.cf`

* Update CHANGELOG.md

---------

Co-authored-by: Brennan Kinney <5098581+polarathene@users.noreply.github.com>
This commit is contained in:
Georg Lauterbach 2024-01-04 22:13:13 +01:00 committed by GitHub
parent 25c7024cc4
commit bf69ef248e
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
3 changed files with 8 additions and 3 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

4
CHANGELOG.md
View file

@ -25,6 +25,10 @@ DMS is now secured against the [recently published spoofing attack "SMTP Smuggli
- `swaks` handles pipelining correctly, hence we can now use `reject_unauth_pipelining` in Postfix's configuration.
- `swaks` provides better CLI options that make many files superflous.
- `swaks` can also replace `openssl s_client` and handles authentication on submission ports better.
- **Postfix:**
- We now defer rejection from unauthorized pipelining until the SMTP `DATA` command via `smtpd_data_restrictions` (_i.e. at the end of the mail transfer transaction_) ([#3744](https://github.com/docker-mailserver/docker-mailserver/pull/3744))
- Prevously our configuration only handled this during the client and recipient restriction stages. Postfix will flag this activity when encountered, but the rejection now is handled at `DATA` where unauthorized pipelining would have been valid from this point.
- If you had the Amavis service enabled (default), this restriction was already in place. Otherwise the concerns expressed with `smtpd_data_restrictions = reject_unauth_pipelining` from the security section above apply. We have permitted trusted clients (_`$mynetworks` or authenticated_) to bypass this restriction.
## [v13.1.0](https://github.com/docker-mailserver/docker-mailserver/releases/tag/v13.1.0)

5
target/postfix/main.cf
View file

@ -51,10 +51,11 @@ smtpd_helo_required = yes
smtpd_delay_reject = yes
smtpd_helo_restrictions = permit_mynetworks, reject_invalid_helo_hostname, permit
smtpd_relay_restrictions = permit_mynetworks permit_sasl_authenticated defer_unauth_destination
smtpd_recipient_restrictions = permit_sasl_authenticated, permit_mynetworks, reject_unauth_destination, reject_unauth_pipelining, reject_invalid_helo_hostname, reject_non_fqdn_helo_hostname, reject_unknown_recipient_domain
smtpd_client_restrictions = permit_mynetworks, permit_sasl_authenticated, reject_unauth_destination, reject_unauth_pipelining
smtpd_recipient_restrictions = permit_sasl_authenticated, permit_mynetworks, reject_unauth_destination, reject_invalid_helo_hostname, reject_non_fqdn_helo_hostname, reject_unknown_recipient_domain
smtpd_client_restrictions = permit_mynetworks, permit_sasl_authenticated, reject_unauth_destination
smtpd_sender_restrictions = $dms_smtpd_sender_restrictions
smtpd_discard_ehlo_keywords = silent-discard, dsn
smtpd_data_restrictions = permit_mynetworks, permit_sasl_authenticated, reject_unauth_pipelining
disable_vrfy_command = yes
# Security - Prevent SMTP Smuggling attack

2
test/tests/parallel/set1/spam_virus/postgrey_enabled.bats
View file

@ -44,7 +44,7 @@ function teardown_file() { _default_teardown ; }
# The other spam checks in `main.cf:smtpd_recipient_restrictions` would interfere with testing postgrey.
_run_in_container sed -i \
-e 's/permit_sasl_authenticated.*policyd-spf,$//g' \
-e 's/reject_unauth_pipelining.*reject_unknown_recipient_domain,$//g' \
-e 's/reject_invalid_helo_hostname.*reject_unknown_recipient_domain,$//g' \
-e 's/reject_rbl_client.*inet:127\.0\.0\.1:10023$//g' \
-e 's/smtpd_recipient_restrictions =/smtpd_recipient_restrictions = check_policy_service inet:127.0.0.1:10023/g' \
/etc/postfix/main.cf