Use DKIM selector from Redis

data/Dockerfiles/rspamd/Dockerfile

@@ -13,7 +13,7 @@ RUN echo '.include $LOCAL_CONFDIR/local.d/rspamd.conf.local' > /etc/rspamd/rspam
 
 COPY settings.conf /etc/rspamd/modules.d/settings.conf
 COPY antivirus.conf /etc/rspamd/modules.d/antivirus.conf
-
+COPY dkim_signing.lua /usr/share/rspamd/lua/dkim_signing.lua
 RUN pip install -U oletools
 
 CMD /usr/bin/rspamd -f -u _rspamd -g _rspamd

data/Dockerfiles/rspamd/dkim_signing.lua

@@ -0,0 +1,287 @@
+--[[
+Copyright (c) 2016, Andrew Lewis <nerf@judo.za.org>
+Copyright (c) 2016, Vsevolod Stakhov <vsevolod@highsecure.ru>
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+]]--
+
+local rspamd_logger = require "rspamd_logger"
+local rspamd_util = require "rspamd_util"
+
+if confighelp then
+  return
+end
+
+local settings = {
+  allow_envfrom_empty = true,
+  allow_hdrfrom_mismatch = false,
+  allow_hdrfrom_mismatch_local = false,
+  allow_hdrfrom_mismatch_sign_networks = false,
+  allow_hdrfrom_multiple = false,
+  allow_username_mismatch = false,
+  auth_only = true,
+  domain = {},
+  path = string.format('%s/%s/%s', rspamd_paths['DBDIR'], 'dkim', '$domain.$selector.key'),
+  sign_local = true,
+  selector = 'dkim',
+  symbol = 'DKIM_SIGNED',
+  try_fallback = true,
+  use_domain = 'header',
+  use_esld = true,
+  use_redis = false,
+  key_prefix = 'dkim_keys', -- default hash name
+}
+
+local E = {}
+local N = 'dkim_signing'
+local redis_params
+
+local function simple_template(tmpl, keys)
+  local lpeg = require "lpeg"
+
+  local var_lit = lpeg.P { lpeg.R("az") + lpeg.R("AZ") + lpeg.R("09") + "_" }
+  local var = lpeg.P { (lpeg.P("$") / "") * ((var_lit^1) / keys) }
+  local var_braced = lpeg.P { (lpeg.P("${") / "") * ((var_lit^1) / keys) * (lpeg.P("}") / "") }
+
+  local template_grammar = lpeg.Cs((var + var_braced + 1)^0)
+
+  return lpeg.match(template_grammar, tmpl)
+end
+
+local function dkim_signing_cb(task)
+  local is_local, is_sign_networks
+  local auser = task:get_user()
+  local ip = task:get_from_ip()
+  if ip and ip:is_local() then
+    is_local = true
+  end
+  if settings.auth_only and not auser then
+    if (settings.sign_networks and settings.sign_networks:get_key(ip)) then
+      is_sign_networks = true
+      rspamd_logger.debugm(N, task, 'mail is from address in sign_networks')
+    elseif settings.sign_local and is_local then
+      rspamd_logger.debugm(N, task, 'mail is from local address')
+    else
+      rspamd_logger.debugm(N, task, 'ignoring unauthenticated mail')
+      return
+    end
+  end
+  local efrom = task:get_from('smtp')
+  if not settings.allow_envfrom_empty and
+      #(((efrom or E)[1] or E).addr or '') == 0 then
+    rspamd_logger.debugm(N, task, 'empty envelope from not allowed')
+    return false
+  end
+  local hfrom = task:get_from('mime')
+  if not settings.allow_hdrfrom_multiple and (hfrom or E)[2] then
+    rspamd_logger.debugm(N, task, 'multiple header from not allowed')
+    return false
+  end
+  local dkim_domain
+  local hdom = ((hfrom or E)[1] or E).domain
+  local edom = ((efrom or E)[1] or E).domain
+  if hdom then
+    hdom = hdom:lower()
+  end
+  if edom then
+    edom = edom:lower()
+  end
+  if settings.use_domain_sign_networks and is_sign_networks then
+    if settings.use_domain_sign_networks == 'header' then
+      dkim_domain = hdom
+    else
+      dkim_domain = edom
+    end
+  elseif settings.use_domain_local and is_local then
+    if settings.use_domain_local == 'header' then
+      dkim_domain = hdom
+    else
+      dkim_domain = edom
+    end
+  else
+    if settings.use_domain == 'header' then
+      dkim_domain = hdom
+    else
+      dkim_domain = edom
+    end
+  end
+  if not dkim_domain then
+    rspamd_logger.debugm(N, task, 'could not extract dkim domain')
+    return false
+  end
+  if settings.use_esld then
+    dkim_domain = rspamd_util.get_tld(dkim_domain)
+    if settings.use_domain == 'envelope' and hdom then
+      hdom = rspamd_util.get_tld(hdom)
+    elseif settings.use_domain == 'header' and edom then
+      edom = rspamd_util.get_tld(edom)
+    end
+  end
+  if edom and hdom and not settings.allow_hdrfrom_mismatch and hdom ~= edom then
+    if settings.allow_hdrfrom_mismatch_local and is_local then
+      rspamd_logger.debugm(N, task, 'domain mismatch allowed for local IP: %1 != %2', hdom, edom)
+    elseif settings.allow_hdrfrom_mismatch_sign_networks and is_sign_networks then
+      rspamd_logger.debugm(N, task, 'domain mismatch allowed for sign_networks: %1 != %2', hdom, edom)
+    else
+      rspamd_logger.debugm(N, task, 'domain mismatch not allowed: %1 != %2', hdom, edom)
+      return false
+    end
+  end
+  if auser and not settings.allow_username_mismatch then
+    local udom = string.match(auser, '.*@(.*)')
+    if not udom then
+      rspamd_logger.debugm(N, task, 'couldnt find domain in username')
+      return false
+    end
+    if settings.use_esld then
+      udom = rspamd_util.get_tld(udom)
+    end
+    if udom ~= dkim_domain then
+      rspamd_logger.debugm(N, task, 'user domain mismatch')
+      return false
+    end
+  end
+  local p = {}
+  if settings.domain[dkim_domain] then
+    p.selector = settings.domain[dkim_domain].selector
+    p.key = settings.domain[dkim_domain].path
+  end
+  if not (p.key and p.selector) and not
+    (settings.try_fallback or settings.use_redis or settings.selector_map or settings.path_map) then
+    rspamd_logger.debugm(N, task, 'dkim unconfigured and fallback disabled')
+    return false
+  end
+  if not p.key then
+    if not settings.use_redis then
+      p.key = settings.path
+    end
+  end
+  if not p.selector then
+    p.selector = settings.selector
+  end
+  p.domain = dkim_domain
+
+  if settings.selector_map then
+    local data = settings.selector_map:get_key(dkim_domain)
+    if data then
+      p.selector = data
+    end
+  end
+
+  if settings.path_map then
+    local data = settings.path_map:get_key(dkim_domain)
+    if data then
+      p.key = data
+    end
+  end
+
+  if settings.use_redis then
+    local function try_redis_key(selector)
+      p.key = nil
+      p.selector = selector
+      local rk = string.format('%s.%s', p.selector, p.domain)
+      local function redis_key_cb(err, data)
+        if err or type(data) ~= 'string' then
+          rspamd_logger.infox(rspamd_config, "cannot make request to load DKIM key for %s: %s",
+            rk, err)
+        else
+          p.rawkey = data
+          if rspamd_plugins.dkim.sign(task, p) then
+            task:insert_result(settings.symbol, 1.0)
+          end
+        end
+      end
+      local ret = rspamd_redis_make_request(task,
+        redis_params, -- connect params
+        rk, -- hash key
+        false, -- is write
+        redis_key_cb, --callback
+        'HGET', -- command
+        {settings.key_prefix, rk} -- arguments
+      )
+      if not ret then
+        rspamd_logger.infox(rspamd_config, "cannot make request to load DKIM key for %s", rk)
+      end
+    end
+    if settings.selector_prefix then
+      rspamd_logger.infox(rspamd_config, "Using selector prefix %s for domain %s", settings.selector_prefix, p.domain);
+      local function redis_selector_cb(err, data)
+        if err or type(data) ~= 'string' then
+          rspamd_logger.infox(rspamd_config, "cannot make request to load DKIM selector for domain %s: %s", p.domain, err)
+        else
+          try_redis_key(data)
+        end
+      end
+      local ret = rspamd_redis_make_request(task,
+        redis_params, -- connect params
+        p.domain, -- hash key
+        false, -- is write
+        redis_selector_cb, --callback
+        'HGET', -- command
+        {settings.selector_prefix, p.domain} -- arguments
+      )
+      if not ret then
+        rspamd_logger.infox(rspamd_config, "cannot make request to load DKIM selector for %s", p.domain)
+      end
+    else
+      if not p.selector then
+        rspamd_logger.errx(task, 'No selector specified')
+        return false
+      end
+      try_redis_key(p.selector)
+    end
+  else
+    if (p.key and p.selector) then
+      p.key = simple_template(p.key, {domain = p.domain, selector = p.selector})
+      return rspamd_plugins.dkim.sign(task, p)
+    else
+      rspamd_logger.infox(task, 'key path or dkim selector unconfigured; no signing')
+      return false
+    end
+  end
+end
+
+local opts =  rspamd_config:get_all_opt('dkim_signing')
+if not opts then return end
+for k,v in pairs(opts) do
+  if k == 'sign_networks' then
+    settings[k] = rspamd_map_add(N, k, 'radix', 'DKIM signing networks')
+  elseif k == 'path_map' then
+    settings[k] = rspamd_map_add(N, k, 'map', 'Paths to DKIM signing keys')
+  elseif k == 'selector_map' then
+    settings[k] = rspamd_map_add(N, k, 'map', 'DKIM selectors')
+  else
+    settings[k] = v
+  end
+end
+if not (settings.use_redis or settings.path or settings.domain or settings.path_map or settings.selector_map) then
+  rspamd_logger.infox(rspamd_config, 'mandatory parameters missing, disable dkim signing')
+  return
+end
+if settings.use_redis then
+  redis_params = rspamd_parse_redis_server('dkim_signing')
+
+  if not redis_params then
+    rspamd_logger.errx(rspamd_config, 'no servers are specified, but module is configured to load keys from redis, disable dkim signing')
+    return
+  end
+end
+if settings.use_domain ~= 'header' and settings.use_domain ~= 'envelope' then
+  rspamd_logger.errx(rspamd_config, "Value for 'use_domain' is invalid")
+  settings.use_domain = 'header'
+end
+
+rspamd_config:register_symbol({
+  name = settings['symbol'],
+  callback = dkim_signing_cb
+})

data/Dockerfiles/rspamd/docker-entrypoint.sh

@@ -0,0 +1,10 @@
+#!/bin/bash
+set -e
+
+if [[ ! -d "/data/dkim/txt" || ! -d "/data/dkim/keys" ]] ; then	mkdir -p /data/dkim/{txt,keys} ; chown -R www-data:www-data /data/dkim; fi
+if [[ $(stat -c %U /data/dkim/) != "www-data" ]] ; then chown -R www-data:www-data /data/dkim ; fi
+
+# Migrate domain table to redis
+
+
+exec "$@"