DKIM/CHUNKING: support CHUNKING when a transport_filter is used, if DKIM signing...

diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt
index c8b999c9f6201f17bdccf6b9681828a96e57661f..62109e91553cbca7c9068a18894975cd73d8080b 100644 (file)
--- a/doc/doc-docbook/spec.xfpt
+++ b/doc/doc-docbook/spec.xfpt
@@ -24897,6 +24897,9 @@ unauthenticated. See also &%hosts_require_auth%&, and chapter
 .cindex "RFC 3030" "CHUNKING"
 This option provides a list of servers to which, provided they announce
 CHUNKING support, Exim will attempt to use BDAT commands rather than DATA.
+.new
+Unless DKIM signing is being done,
+.wen
 BDAT will not be used in conjunction with a transport filter.
 
 .option hosts_try_dane smtp "host list&!!" *

diff --git a/doc/doc-txt/ChangeLog b/doc/doc-txt/ChangeLog
index 45d126ccdf9bf9ee4c61f7320c153af9da0493f3..f9e39d2dc09f2f8bd9e03a7bca003b693021da38 100644 (file)
--- a/doc/doc-txt/ChangeLog
+++ b/doc/doc-txt/ChangeLog
@@ -18,6 +18,10 @@ JH/03 DKIM verification defaults no long accept sha1 hashes, to conform to
       RFC 8301.  They can still be enabled, using the dkim_verify_hashes main
       option.
 
+JH/04 Support CHUNKING from an smtp transport using a transport_filter, when
+      DKIM signing is being done.  Previously a transport_filter would always
+      disable CHUNKING, falling back to traditional DATA.
+
 
 Exim version 4.93
 -----------------

diff --git a/src/src/transports/smtp.c b/src/src/transports/smtp.c
index b16b8b110ce3c93f2e58c9687c1670d2e00ac8e4..383d202b9ab73004e316056026cc9f54de908e27 100644 (file)
--- a/src/src/transports/smtp.c
+++ b/src/src/transports/smtp.c
@@ -3571,6 +3571,11 @@ if (tblock->filter_command)
      && *transport_filter_argv
      && **transport_filter_argv
      && sx.peer_offered & OPTION_CHUNKING
+#ifndef DISABLE_DKIM
+    /* When dkim signing, chunking is handled even with a transport-filter */
+     && !(ob->dkim.dkim_private_key && ob->dkim.dkim_domain && ob->dkim.dkim_selector)
+     && !ob->dkim.force_bodyhash
+#endif
      )
     {
     sx.peer_offered &= ~OPTION_CHUNKING;

diff --git a/test/aux-fixed/4525.mlistfooter b/test/aux-fixed/4525.mlistfooter
new file mode 100644 (file)
index 0000000..7c33b82
--- /dev/null
+++ b/test/aux-fixed/4525.mlistfooter
@@ -0,0 +1,4 @@
+
+-- 
+This is a generic mailinglist footer, using a traditional .sig-separator line
+----

diff --git a/test/confs/4525 b/test/confs/4525
new file mode 100644 (file)
index 0000000..3a843b9
--- /dev/null
+++ b/test/confs/4525
@@ -0,0 +1,113 @@
+# Exim test configuration 4525
+
+SERVER=
+OPT=
+FAKE =
+
+keep_environment = PATH:EXIM_TESTHARNESS_DISABLE_OCSPVALIDITYCHECK
+add_environment = SSLKEYLOGFILE=/home/jgh/git/exim/test/spool/sslkeys
+exim_path = EXIM_PATH
+host_lookup_order = bydns
+spool_directory = /home/jgh/git/exim/test/spool
+
+.ifdef SERVER
+log_file_path = /home/jgh/git/exim/test/spool/log/SERVER%slog
+.else
+log_file_path = /home/jgh/git/exim/test/spool/log/%slog
+.endif
+
+gecos_pattern = ""
+gecos_name = CALLER_NAME
+dns_cname_loops = 9
+chunking_advertise_hosts = *
+
+.ifdef _HAVE_REQTLS
+tls_advertise_requiretls =
+.endif
+.ifdef _HAVE_PIPE_CONNECT
+pipelining_connect_advertise_hosts = :
+.endif
+.ifdef _HAVE_DMARC
+dmarc_tld_file =
+.endif
+tls_advertise_hosts =
+
+primary_hostname = myhost.test.ex
+
+# ----- Main settings -----
+
+acl_smtp_rcpt = accept logwrite = rcpt acl: macro: _DKIM_SIGN_HEADERS
+acl_smtp_dkim = accept logwrite = dkim_acl: signer: $dkim_cur_signer bits: $dkim_key_length h=$dkim_headernames
+acl_smtp_data = accept logwrite = data acl: dkim status $dkim_verify_status
+
+dkim_verify_signers = $dkim_signers
+
+DDIR=DIR/aux-fixed/dkim
+
+log_selector = +received_recipients
+
+
+# ----- Routers
+
+begin routers
+
+server_store:
+  driver =     accept
+  condition =  ${if eq {SERVER}{server}{yes}{no}}
+  transport =  file
+
+client:
+  driver =     accept
+  transport =  send_to_server
+
+# ----- Transports
+
+begin transports
+
+send_to_server:
+  driver = smtp
+  allow_localhost
+  hosts = HOSTIPV4
+  port = PORT_D
+
+.ifdef FILTER
+  transport_filter =   /bin/cat - DIR/aux-fixed/TESTNUM.mlistfooter
+.endif
+.ifndef ALLOW
+  hosts_try_chunking = :
+.endif
+
+  dkim_domain =                test.ex
+.ifdef SELECTOR
+  dkim_selector =      SELECTOR
+.else
+  dkim_selector =      sel
+.endif
+
+  dkim_private_key =   ${extract {${length_3:$dkim_selector}} {\
+                               ses=dkim512.private \
+                               sel=dkim.private \
+                               sed=dkim_ed25519.private \
+                               }{DDIR/$value}}
+
+.ifndef HEADERS_MAXSIZE
+  dkim_sign_headers =  OPT
+.else
+  dkim_identity =      allheaders@$dkim_domain
+.endif
+.ifdef VALUE
+  dkim_hash =          VALUE
+.endif
+.ifdef STRICT
+  dkim_strict =                STRICT
+.endif
+.ifdef TIMES
+  dkim_timestamps =    TIMES
+.endif
+
+file:
+  driver =     appendfile
+  file =       DIR/test-mail/$local_part
+  user =       CALLER
+
+# End

diff --git a/test/log/4525 b/test/log/4525
new file mode 100644 (file)
index 0000000..f4b7496
--- /dev/null
+++ b/test/log/4525
@@ -0,0 +1,48 @@
+1999-03-02 09:44:33 10HmaX-0005vi-00 <= CALLER@myhost.test.ex U=CALLER P=local S=sss for a@test.ex
+1999-03-02 09:44:33 10HmaX-0005vi-00 => a@test.ex R=client T=send_to_server H=ip4.ip4.ip4.ip4 [ip4.ip4.ip4.ip4] C="250 OK id=10HmaY-0005vi-00"
+1999-03-02 09:44:33 10HmaX-0005vi-00 Completed
+1999-03-02 09:44:33 10HmaZ-0005vi-00 <= CALLER@myhost.test.ex U=CALLER P=local S=sss for b@test.ex
+1999-03-02 09:44:33 10HmaZ-0005vi-00 => b@test.ex R=client T=send_to_server H=ip4.ip4.ip4.ip4 [ip4.ip4.ip4.ip4] C="250 OK id=10HmbA-0005vi-00"
+1999-03-02 09:44:33 10HmaZ-0005vi-00 Completed
+1999-03-02 09:44:33 10HmbB-0005vi-00 <= CALLER@myhost.test.ex U=CALLER P=local S=sss for c@test.ex
+1999-03-02 09:44:33 10HmbB-0005vi-00 => c@test.ex R=client T=send_to_server H=ip4.ip4.ip4.ip4 [ip4.ip4.ip4.ip4] K C="250- 7nn byte chunk, total 7nn\\n250 OK id=10HmbC-0005vi-00"
+1999-03-02 09:44:33 10HmbB-0005vi-00 Completed
+1999-03-02 09:44:33 10HmbD-0005vi-00 <= CALLER@myhost.test.ex U=CALLER P=local S=sss for b@test.ex
+1999-03-02 09:44:33 10HmbD-0005vi-00 => b@test.ex R=client T=send_to_server H=ip4.ip4.ip4.ip4 [ip4.ip4.ip4.ip4] C="250 OK id=10HmbE-0005vi-00"
+1999-03-02 09:44:33 10HmbD-0005vi-00 Completed
+1999-03-02 09:44:33 10HmbF-0005vi-00 <= CALLER@myhost.test.ex U=CALLER P=local S=sss for c@test.ex
+1999-03-02 09:44:33 10HmbF-0005vi-00 => c@test.ex R=client T=send_to_server H=ip4.ip4.ip4.ip4 [ip4.ip4.ip4.ip4] K C="250- 7nn byte chunk, total 7nn\\n250 OK id=10HmbG-0005vi-00"
+1999-03-02 09:44:33 10HmbF-0005vi-00 Completed
+
+******** SERVER ********
+1999-03-02 09:44:33 exim x.yz daemon started: pid=pppp, no queue runs, listening for SMTP on port PORT_D
+1999-03-02 09:44:33 rcpt acl: macro: From:Sender:Reply-To:Subject:Date:Message-ID:To:Cc:MIME-Version:Content-Type:Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Id:List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive
+1999-03-02 09:44:33 10HmaY-0005vi-00 dkim_acl: signer: test.ex bits: 1024 h=From
+1999-03-02 09:44:33 10HmaY-0005vi-00 data acl: dkim status pass
+1999-03-02 09:44:33 10HmaY-0005vi-00 <= CALLER@myhost.test.ex H=the.local.host.name (myhost.test.ex) [ip4.ip4.ip4.ip4] P=esmtp S=sss DKIM=test.ex id=E10HmaX-0005vi-00@myhost.test.ex for a@test.ex
+1999-03-02 09:44:33 10HmaY-0005vi-00 => a <a@test.ex> R=server_store T=file
+1999-03-02 09:44:33 10HmaY-0005vi-00 Completed
+1999-03-02 09:44:33 rcpt acl: macro: From:Sender:Reply-To:Subject:Date:Message-ID:To:Cc:MIME-Version:Content-Type:Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Id:List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive
+1999-03-02 09:44:33 10HmbA-0005vi-00 dkim_acl: signer: test.ex bits: 1024 h=From
+1999-03-02 09:44:33 10HmbA-0005vi-00 data acl: dkim status pass
+1999-03-02 09:44:33 10HmbA-0005vi-00 <= CALLER@myhost.test.ex H=the.local.host.name (myhost.test.ex) [ip4.ip4.ip4.ip4] P=esmtp S=sss DKIM=test.ex id=E10HmaZ-0005vi-00@myhost.test.ex for b@test.ex
+1999-03-02 09:44:33 10HmbA-0005vi-00 => b <b@test.ex> R=server_store T=file
+1999-03-02 09:44:33 10HmbA-0005vi-00 Completed
+1999-03-02 09:44:33 rcpt acl: macro: From:Sender:Reply-To:Subject:Date:Message-ID:To:Cc:MIME-Version:Content-Type:Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Id:List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive
+1999-03-02 09:44:33 10HmbC-0005vi-00 dkim_acl: signer: test.ex bits: 1024 h=From
+1999-03-02 09:44:33 10HmbC-0005vi-00 data acl: dkim status pass
+1999-03-02 09:44:33 10HmbC-0005vi-00 <= CALLER@myhost.test.ex H=the.local.host.name (myhost.test.ex) [ip4.ip4.ip4.ip4] P=esmtp K S=sss DKIM=test.ex id=E10HmbB-0005vi-00@myhost.test.ex for c@test.ex
+1999-03-02 09:44:33 10HmbC-0005vi-00 => c <c@test.ex> R=server_store T=file
+1999-03-02 09:44:33 10HmbC-0005vi-00 Completed
+1999-03-02 09:44:33 rcpt acl: macro: From:Sender:Reply-To:Subject:Date:Message-ID:To:Cc:MIME-Version:Content-Type:Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Id:List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive
+1999-03-02 09:44:33 10HmbE-0005vi-00 dkim_acl: signer: test.ex bits: 1024 h=From
+1999-03-02 09:44:33 10HmbE-0005vi-00 data acl: dkim status pass
+1999-03-02 09:44:33 10HmbE-0005vi-00 <= CALLER@myhost.test.ex H=the.local.host.name (myhost.test.ex) [ip4.ip4.ip4.ip4] P=esmtp S=sss DKIM=test.ex id=E10HmbD-0005vi-00@myhost.test.ex for b@test.ex
+1999-03-02 09:44:33 10HmbE-0005vi-00 => b <b@test.ex> R=server_store T=file
+1999-03-02 09:44:33 10HmbE-0005vi-00 Completed
+1999-03-02 09:44:33 rcpt acl: macro: From:Sender:Reply-To:Subject:Date:Message-ID:To:Cc:MIME-Version:Content-Type:Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Id:List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive
+1999-03-02 09:44:33 10HmbG-0005vi-00 dkim_acl: signer: test.ex bits: 1024 h=From
+1999-03-02 09:44:33 10HmbG-0005vi-00 data acl: dkim status pass
+1999-03-02 09:44:33 10HmbG-0005vi-00 <= CALLER@myhost.test.ex H=the.local.host.name (myhost.test.ex) [ip4.ip4.ip4.ip4] P=esmtp K S=sss DKIM=test.ex id=E10HmbF-0005vi-00@myhost.test.ex for c@test.ex
+1999-03-02 09:44:33 10HmbG-0005vi-00 => c <c@test.ex> R=server_store T=file
+1999-03-02 09:44:33 10HmbG-0005vi-00 Completed

diff --git a/test/mail/4525.a b/test/mail/4525.a
new file mode 100644 (file)
index 0000000..2f78aec
--- /dev/null
+++ b/test/mail/4525.a
@@ -0,0 +1,22 @@
+From CALLER@myhost.test.ex Tue Mar 02 09:44:33 1999
+Received: from the.local.host.name ([ip4.ip4.ip4.ip4] helo=myhost.test.ex)
+       by myhost.test.ex with esmtp (Exim x.yz)
+       (envelope-from <CALLER@myhost.test.ex>)
+       id 10HmaY-0005vi-00
+       for a@test.ex; Tue, 2 Mar 1999 09:44:33 +0000
+DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=test.ex;
+       s=sel; h=From; bh=/Ab0giHZitYQbDhFszoqQRUkgqueaX9zatJttIU/plc=; b=toy5chxow6W
+       7Nn3qMvjZs+i0H00bQfi+6nakV6i36cRrZM/oWziHrc5IfYZuQunWNUA9UHnatK35Nsl7ZJRBU4em
+       wtzdO60jXnH7ZVyYjKxqTow9uCuuBKCgXdKxt1hpEfY0m7uUKt9OaqA0464NH5wEC4o/pt1aReidE
+       hvI6IY=;
+Received: from CALLER by myhost.test.ex with local (Exim x.yz)
+       (envelope-from <CALLER@myhost.test.ex>)
+       id 10HmaX-0005vi-00
+       for a@test.ex; Tue, 2 Mar 1999 09:44:33 +0000
+From: nobody@example.com
+Message-Id: <E10HmaX-0005vi-00@myhost.test.ex>
+Sender: CALLER_NAME <CALLER@myhost.test.ex>
+Date: Tue, 2 Mar 1999 09:44:33 +0000
+
+content
+

diff --git a/test/mail/4525.b b/test/mail/4525.b
new file mode 100644 (file)
index 0000000..6cd2538
--- /dev/null
+++ b/test/mail/4525.b
@@ -0,0 +1,52 @@
+From CALLER@myhost.test.ex Tue Mar 02 09:44:33 1999
+Received: from the.local.host.name ([ip4.ip4.ip4.ip4] helo=myhost.test.ex)
+       by myhost.test.ex with esmtp (Exim x.yz)
+       (envelope-from <CALLER@myhost.test.ex>)
+       id 10HmbA-0005vi-00
+       for b@test.ex; Tue, 2 Mar 1999 09:44:33 +0000
+DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=test.ex;
+       s=sel; h=From; bh=bzHKix52TV0ojCi2kd18gmIw/tcd5TnhO3QM+89xwyk=; b=LcQAFwKN9DL
+       wCbK0mcUtjmEoLaNUjwHmVrilQI1nBWJDoDUzpUl96U8YzdS/+Xut+pdS/YZf3m/Qbcw6ohO9pEmM
+       ncfURg55wr8fftAyRFA/L/svtP8h3Qv/+jv8gJ9nHyjk3z7Zmzzo8S54h9Ct9pJwkv0cpmdeLiDrL
+       ygZGjs=;
+Received: from CALLER by myhost.test.ex with local (Exim x.yz)
+       (envelope-from <CALLER@myhost.test.ex>)
+       id 10HmaZ-0005vi-00
+       for b@test.ex; Tue, 2 Mar 1999 09:44:33 +0000
+From: nobody@example.com
+Message-Id: <E10HmaZ-0005vi-00@myhost.test.ex>
+Sender: CALLER_NAME <CALLER@myhost.test.ex>
+Date: Tue, 2 Mar 1999 09:44:33 +0000
+
+content
+
+-- 
+This is a generic mailinglist footer, using a traditional .sig-separator line
+----
+
+From CALLER@myhost.test.ex Tue Mar 02 09:44:33 1999
+Received: from the.local.host.name ([ip4.ip4.ip4.ip4] helo=myhost.test.ex)
+       by myhost.test.ex with esmtp (Exim x.yz)
+       (envelope-from <CALLER@myhost.test.ex>)
+       id 10HmbE-0005vi-00
+       for b@test.ex; Tue, 2 Mar 1999 09:44:33 +0000
+DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=test.ex;
+       s=sel; h=From; bh=bzHKix52TV0ojCi2kd18gmIw/tcd5TnhO3QM+89xwyk=; b=LcQAFwKN9DL
+       wCbK0mcUtjmEoLaNUjwHmVrilQI1nBWJDoDUzpUl96U8YzdS/+Xut+pdS/YZf3m/Qbcw6ohO9pEmM
+       ncfURg55wr8fftAyRFA/L/svtP8h3Qv/+jv8gJ9nHyjk3z7Zmzzo8S54h9Ct9pJwkv0cpmdeLiDrL
+       ygZGjs=;
+Received: from CALLER by myhost.test.ex with local (Exim x.yz)
+       (envelope-from <CALLER@myhost.test.ex>)
+       id 10HmbD-0005vi-00
+       for b@test.ex; Tue, 2 Mar 1999 09:44:33 +0000
+From: nobody@example.com
+Message-Id: <E10HmbD-0005vi-00@myhost.test.ex>
+Sender: CALLER_NAME <CALLER@myhost.test.ex>
+Date: Tue, 2 Mar 1999 09:44:33 +0000
+
+content
+
+-- 
+This is a generic mailinglist footer, using a traditional .sig-separator line
+----
+

diff --git a/test/mail/4525.c b/test/mail/4525.c
new file mode 100644 (file)
index 0000000..1032c0d
--- /dev/null
+++ b/test/mail/4525.c
@@ -0,0 +1,52 @@
+From CALLER@myhost.test.ex Tue Mar 02 09:44:33 1999
+Received: from the.local.host.name ([ip4.ip4.ip4.ip4] helo=myhost.test.ex)
+       by myhost.test.ex with esmtp (Exim x.yz)
+       (envelope-from <CALLER@myhost.test.ex>)
+       id 10HmbC-0005vi-00
+       for c@test.ex; Tue, 2 Mar 1999 09:44:33 +0000
+DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=test.ex;
+       s=sel; h=From; bh=bzHKix52TV0ojCi2kd18gmIw/tcd5TnhO3QM+89xwyk=; b=LcQAFwKN9DL
+       wCbK0mcUtjmEoLaNUjwHmVrilQI1nBWJDoDUzpUl96U8YzdS/+Xut+pdS/YZf3m/Qbcw6ohO9pEmM
+       ncfURg55wr8fftAyRFA/L/svtP8h3Qv/+jv8gJ9nHyjk3z7Zmzzo8S54h9Ct9pJwkv0cpmdeLiDrL
+       ygZGjs=;
+Received: from CALLER by myhost.test.ex with local (Exim x.yz)
+       (envelope-from <CALLER@myhost.test.ex>)
+       id 10HmbB-0005vi-00
+       for c@test.ex; Tue, 2 Mar 1999 09:44:33 +0000
+From: nobody@example.com
+Message-Id: <E10HmbB-0005vi-00@myhost.test.ex>
+Sender: CALLER_NAME <CALLER@myhost.test.ex>
+Date: Tue, 2 Mar 1999 09:44:33 +0000
+
+content
+
+-- 
+This is a generic mailinglist footer, using a traditional .sig-separator line
+----
+
+From CALLER@myhost.test.ex Tue Mar 02 09:44:33 1999
+Received: from the.local.host.name ([ip4.ip4.ip4.ip4] helo=myhost.test.ex)
+       by myhost.test.ex with esmtp (Exim x.yz)
+       (envelope-from <CALLER@myhost.test.ex>)
+       id 10HmbG-0005vi-00
+       for c@test.ex; Tue, 2 Mar 1999 09:44:33 +0000
+DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=test.ex;
+       s=sel; h=From; bh=bzHKix52TV0ojCi2kd18gmIw/tcd5TnhO3QM+89xwyk=; b=LcQAFwKN9DL
+       wCbK0mcUtjmEoLaNUjwHmVrilQI1nBWJDoDUzpUl96U8YzdS/+Xut+pdS/YZf3m/Qbcw6ohO9pEmM
+       ncfURg55wr8fftAyRFA/L/svtP8h3Qv/+jv8gJ9nHyjk3z7Zmzzo8S54h9Ct9pJwkv0cpmdeLiDrL
+       ygZGjs=;
+Received: from CALLER by myhost.test.ex with local (Exim x.yz)
+       (envelope-from <CALLER@myhost.test.ex>)
+       id 10HmbF-0005vi-00
+       for c@test.ex; Tue, 2 Mar 1999 09:44:33 +0000
+From: nobody@example.com
+Message-Id: <E10HmbF-0005vi-00@myhost.test.ex>
+Sender: CALLER_NAME <CALLER@myhost.test.ex>
+Date: Tue, 2 Mar 1999 09:44:33 +0000
+
+content
+
+-- 
+This is a generic mailinglist footer, using a traditional .sig-separator line
+----
+

diff --git a/test/scripts/4500-DKIM/4525 b/test/scripts/4500-DKIM/4525
new file mode 100644 (file)
index 0000000..dced4ae
--- /dev/null
+++ b/test/scripts/4500-DKIM/4525
@@ -0,0 +1,54 @@
+# DKIM signing, with transport_filter
+#
+exim -bd -DSERVER=server -oX PORT_D
+****
+#
+# baseline (no transport_filter)
+exim -DOPT=From -odf a@test.ex
+From: nobody@example.com
+
+content
+****
+millisleep 500
+#
+#
+# with transport_filter
+exim -DOPT=From -DFILTER=y -odf b@test.ex
+From: nobody@example.com
+
+content
+****
+millisleep 500
+# with transport_filter and CHUNKING
+exim -DOPT=From -DFILTER=y -DALLOW=y -odf c@test.ex
+From: nobody@example.com
+
+content
+****
+millisleep 500
+#
+# for comparison, mails that should get identical sigs, though not using a transport_filter
+exim -DOPT=From -odf b@test.ex
+From: nobody@example.com
+
+content
+
+-- 
+This is a generic mailinglist footer, using a traditional .sig-separator line
+----
+****
+millisleep 500
+exim -DOPT=From -DALLOW=y -odf c@test.ex
+From: nobody@example.com
+
+content
+
+-- 
+This is a generic mailinglist footer, using a traditional .sig-separator line
+----
+****
+millisleep 500
+#
+#
+killdaemon
+no_msglog_check