antispam: rspamd strips a sender's own verdict for every client
test / test (push) Canceled after 0s

rspamd 3.11.1's milter_headers skips its verdict routines - removes none
of the sender's X-Spamd-Result / X-Rspamd-Action, adds none - for a client
it counts as local (loopback, a unix socket, local_addrs: the private
ranges) or one that authenticated (skip_local, skip_authenticated, both on
by default; milter_headers.lua skip_wanted(), lua_ip.c lua_ip_is_local()).
The custom routine that signs X-SelfPost-Filter is never put through
skip_wanted(), so it signed the sender's own verdict, and Inbound > Log
showed it as rspamd's. Every sender is private when Docker's proxy relays
port 25 from the bridge gateway. Both options set to false.

Tried 2026-10-14 in a throwaway rspamd/rspamd:3.11.1-3 on the test server
(rspamc --ucl, a message carrying its own verdict headers): old config,
from 10.0.0.5 and as an authenticated user, the milter reply removed and
added neither and added the signature; new config, both removed and
rspamd's own added, as from 203.0.113.9.

Also: the sender rules take the envelope only (extract_from = "smtp"; by
default a bounce's From: header is used - tried: a bounce whose From:
domain is denied was refused before, is not now; a denied sender is
refused either way); the image pinned to 3.11.1-3, the build read (3.11 and
3.11.1 move with each rebuild); the prefilter lines no longer read go.
architecture.md and security.md say so. Assumptions C-R7, B-R1, C-R4,
C-R12, C-R5.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
This commit is contained in:
mix
2026-10-14 19:48:07 +03:00
co-authored by Claude Opus 5.5
parent a658da11f7
commit 31c2b50457
6 changed files with 90 additions and 20 deletions
+20 -2
View File
@@ -6,8 +6,24 @@
# and the upstream mailbox server receives them with the mail.
#
# rspamd removes headers of these names that a sender wrote himself before it
# adds its own. Without this file the journal still lists accepted mail, with
# no verdict next to it.
# adds its own - for every client, because of the two lines below. Without
# them it would do neither for a client it counts as local or one that
# authenticated: rspamd 3.11.1, src/plugins/lua/milter_headers.lua,
# skip_wanted() - skip_local and skip_authenticated are on by default, and
# "local" is loopback, a unix socket, or an address in local_addrs, the
# private ranges (src/lua/lua_ip.c, lua_ip_is_local(); conf/options.inc). The
# sender's own verdict would then pass untouched while the signature below,
# a custom routine that skip_wanted() never consults, signed it (assumptions
# C-R7). A private client address is ordinary here: a LAN sender, or every
# sender when Docker's proxy relays port 25 from the bridge gateway.
# Tried on 2026-10-14 in a throwaway rspamd/rspamd:3.11.1-3 (rspamc --ucl, a
# message carrying its own X-Spamd-Result and X-Rspamd-Action): without the
# two lines, from 10.0.0.5 or as an authenticated user, the milter reply
# removed neither header, added neither, and added the signature; with
# them, both removed and rspamd's own added, as from a public address.
#
# Without this file the journal still lists accepted mail, with no verdict
# next to it.
#
# The third header is the proof that the other two are rspamd's. The filter is
# attached so that mail still flows when it is down, and then nothing removes
@@ -30,6 +46,8 @@
# end-of-message (Postfix 3.7.11, src/global/mail_params.h, DEF_MILT_EOD_MACROS
# "i").
use = ["x-spamd-result", "x-rspamd-action", "selfpost-signature"];
skip_local = false;
skip_authenticated = false;
custom {
selfpost-signature = <<EOD