[Fix] Perform policy downgrade on sample out, add tests

src/plugins/lua/dmarc.lua

@@ -419,11 +419,19 @@ local function dmarc_validate_policy(task, policy, hdrfromdom, dmarc_esld)
       if (coin > policy.pct) then
         if (not no_sampling_domains or
             not no_sampling_domains:get_key(policy.domain)) then
-          task:insert_result(dmarc_symbols['softfail'], 1.0,
+
+          if what == 'reject' then
+            disposition = 'quarantine'
+          else
+            disposition = 'softfail'
+          end
+
+          task:insert_result(dmarc_symbols[disposition], 1.0,
               policy.domain .. ' : ' .. reason_str, policy.dmarc_policy, "sampled_out")
           sampled_out = true
-          lua_util.debugm(N, task, 'changed dmarc policy from %s to %s, sampled out: %s < %s',
-              what, 'softfail', coin, policy.pct)
+          lua_util.debugm(N, task,
+              'changed dmarc policy from %s to %s, sampled out: %s < %s',
+              what, disposition, coin, policy.pct)
         else
           task:insert_result(dmarc_symbols[what], 1.0,
               policy.domain .. ' : ' .. reason_str, policy.dmarc_policy, "local_policy")

test/functional/cases/115_dmarc.robot

@@ -77,9 +77,14 @@ DMARC NA NXDOMAIN
   ...  -i  37.48.67.26  --from  foo@mom.za.org
   Check Rspamc  ${result}  DMARC_NA
 
-DMARC PCT ZERO
+DMARC PCT ZERO REJECT
   ${result} =  Scan Message With Rspamc  ${TESTDIR}/messages/dmarc/pct_none.eml
   ...  -i  37.48.67.26  --from  foo@mom.za.org
+  Check Rspamc  ${result}  DMARC_POLICY_QUARANTINE
+
+DMARC PCT ZERO SP QUARANTINE
+  ${result} =  Scan Message With Rspamc  ${TESTDIR}/messages/dmarc/pct_none1.eml
+  ...  -i  37.48.67.26  --from  foo@mom.za.org
   Check Rspamc  ${result}  DMARC_POLICY_SOFTFAIL
 
 DKIM PERMFAIL NXDOMAIN

test/functional/messages/dmarc/pct_none1.eml

@@ -0,0 +1,17 @@
+Date: Tue, 09 Aug 2016 10:01:27 +0200
+Message-ID: <20160809100128@rspamd.tk>
+From: Rspamd <foo@subdomain.zero_pct.com>
+To: foo@rspamd.tk
+Subject: hello
+Content-Type: text/plain; charset=utf-8; format=flowed; DelSp=Yes
+MIME-Version: 1.0
+Content-Disposition: inline
+DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rspamd.tk; s=testdkim;
+	t=1470729879; h=from:subject:date:message-id:to:mime-version:content-type;
+	bh=7HkRgYnNru3SR2EWfgWU8yhM0MOH6ZZrPoEIgNIh8wc=;
+	b=kTIV4jcgv9sWFh2JFrS/+PcNxiloituqjmHHqeJOTfa+/9C+Er8BjnMysTJyYVq36Gnv0OZDgLr3Yy4YP5Lzbt1M9ZdN5cJqO7yn1N7wyaGfkt++b09rIYBy5Dkk7OWyP3cDThqDzv8C9heSvqBSEsirFsbt3Wx2g/hWiJlnjew=
+
+
+hello
+
+