--[[
Copyright (c) 2011-2015, 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.
]]--

if confighelp then
  return
end

-- Multimap is rspamd module designed to define and operate with different maps

local rules = {}
local rspamd_logger = require "rspamd_logger"
local cdb = require "rspamd_cdb"
local util = require "rspamd_util"
local regexp = require "rspamd_regexp"
local rspamd_expression = require "rspamd_expression"
local rspamd_ip = require "rspamd_ip"
local lua_util = require "lua_util"
local rspamd_dns = require "rspamd_dns"
local lua_selectors = require "lua_selectors"
local redis_params
local fun = require "fun"
local N = 'multimap'

local urls = {}

local value_types = {
  ip = {
    get_value = function(ip) return ip:to_string() end,
  },
  from = {
    get_value = function(val) return val end,
  },
  helo = {
    get_value = function(val) return val end,
  },
  header = {
    get_value = function(val) return val end,
  },
  rcpt = {
    get_value = function(val) return val end,
  },
  user = {
    get_value = function(val) return val end,
  },
  url = {
    get_value = function(val) return val end,
  },
  dnsbl = {
    get_value = function(ip) return ip:to_string() end,
  },
  filename = {
    get_value = function(val) return val end,
  },
  content = {
    get_value = function() return nil end,
  },
  hostname = {
    get_value = function(val) return val end,
  },
  asn = {
    get_value = function(val) return val end,
  },
  country = {
    get_value = function(val) return val end,
  },
  received = {
    get_value = function(val) return val end,
  },
  mempool = {
    get_value = function(val) return val end,
  },
  selector = {
    get_value = function(val) return val end,
  },
  symbol_options = {
    get_value = function(val) return val end,
  },
}

local function ip_to_rbl(ip, rbl)
  return table.concat(ip:inversed_str_octets(), ".") .. '.' .. rbl
end

local function apply_hostname_filter(task, filter, hostname, r)
  if filter == 'tld' then
    local tld = util.get_tld(hostname)
    return tld
  elseif filter == 'top' then
    local tld = util.get_tld(hostname)
    return tld:match('[^.]*$') or tld
  else
    if not r['re_filter'] then
      local pat = string.match(filter, 'tld:regexp:(.+)')
      if not pat then
        rspamd_logger.errx(task, 'bad search filter: %s', filter)
        return
      end
      r['re_filter'] = regexp.create(pat)
      if not r['re_filter'] then
        rspamd_logger.errx(task, 'couldnt create regex: %s', pat)
        return
      end
    end
    local tld = util.get_tld(hostname)
    local res = r['re_filter']:search(tld)
    if res then
      return res[1]
    else
      return nil
    end
  end
end

local function apply_url_filter(task, filter, url, r)
  if not filter then
    return url:get_host()
  end

  if filter == 'tld' then
    return url:get_tld()
  elseif filter == 'top' then
    local tld = url:get_tld()
    return tld:match('[^.]*$') or tld
  elseif filter == 'full' then
    return url:get_text()
  elseif filter == 'is_phished' then
    if url:is_phished() then
      return url:get_host()
    else
      return nil
    end
  elseif filter == 'is_redirected' then
    if url:is_redirected() then
      return url:get_host()
    else
      return nil
    end
  elseif filter == 'is_obscured' then
    if url:is_obscured() then
      return url:get_host()
    else
      return nil
    end
  elseif filter == 'path' then
    return url:get_path()
  elseif filter == 'query' then
    return url:get_query()
  elseif string.find(filter, 'tag:') then
    local tags = url:get_tags()
    local want_tag = string.match(filter, 'tag:(.*)')
    for _, t in ipairs(tags) do
      if t == want_tag then
        return url:get_host()
      end
    end
    return nil
  elseif string.find(filter, 'tld:regexp:') then
    if not r['re_filter'] then
      local type,pat = string.match(filter, '(regexp:)(.+)')
      if type and pat then
        r['re_filter'] = regexp.create(pat)
      end
    end

    if not r['re_filter'] then
      rspamd_logger.errx(task, 'bad search filter: %s', filter)
    else
      local results = r['re_filter']:search(url:get_tld())
      if results then
        return results[1]
      else
        return nil
      end
    end
  elseif string.find(filter, 'full:regexp:') then
    if not r['re_filter'] then
      local type,pat = string.match(filter, '(regexp:)(.+)')
      if type and pat then
        r['re_filter'] = regexp.create(pat)
      end
    end

    if not r['re_filter'] then
      rspamd_logger.errx(task, 'bad search filter: %s', filter)
    else
      local results = r['re_filter']:search(url:get_text())
      if results then
        return results[1]
      else
        return nil
      end
    end
  elseif string.find(filter, 'regexp:') then
    if not r['re_filter'] then
      local type,pat = string.match(filter, '(regexp:)(.+)')
      if type and pat then
        r['re_filter'] = regexp.create(pat)
      end
    end

    if not r['re_filter'] then
      rspamd_logger.errx(task, 'bad search filter: %s', filter)
    else
      local results = r['re_filter']:search(url:get_host())
      if results then
        return results[1]
      else
        return nil
      end
    end
  elseif string.find(filter, '^template:') then
    if not r['template'] then
      r['template'] = string.match(filter, '^template:(.+)')
    end

    if r['template'] then
      return lua_util.template(r['template'], url:to_table())
    end
  end

  return url:get_host()
end

local function apply_addr_filter(task, filter, input, rule)
  if filter == 'email:addr' or filter == 'email' then
    local addr = util.parse_mail_address(input, task:get_mempool())
    if addr and addr[1] then
      return addr[1]['addr']
    end
  elseif filter == 'email:user' then
    local addr = util.parse_mail_address(input, task:get_mempool())
    if addr and addr[1] then
      return addr[1]['user']
    end
  elseif filter == 'email:domain' then
    local addr = util.parse_mail_address(input, task:get_mempool())
    if addr and addr[1] then
      return addr[1]['domain']
    end
  elseif filter == 'email:domain:tld' then
    local addr = util.parse_mail_address(input, task:get_mempool())
    if addr and addr[1] then
      return util.get_tld(addr[1]['domain'])
    end
  elseif filter == 'email:name' then
    local addr = util.parse_mail_address(input, task:get_mempool())
    if addr and addr[1] then
      return addr[1]['name']
    end
  else
    -- regexp case
    if not rule['re_filter'] then
      local type,pat = string.match(filter, '(regexp:)(.+)')
      if type and pat then
        rule['re_filter'] = regexp.create(pat)
      end
    end

    if not rule['re_filter'] then
      rspamd_logger.errx(task, 'bad search filter: %s', filter)
    else
      local results = rule['re_filter']:search(input)
      if results then
        return results[1]
      end
    end
  end

  return input
end
local function apply_filename_filter(task, filter, fn, r)
  if filter == 'extension' or filter == 'ext' then
    return string.match(fn, '%.([^.]+)$')
  elseif string.find(filter, 'regexp:') then
    if not r['re_filter'] then
      local type,pat = string.match(filter, '(regexp:)(.+)')
      if type and pat then
        r['re_filter'] = regexp.create(pat)
      end
    end

    if not r['re_filter'] then
      rspamd_logger.errx(task, 'bad search filter: %s', filter)
    else
      local results = r['re_filter']:search(fn)
      if results then
        return results[1]
      else
        return nil
      end
    end
  end

  return fn
end

local function apply_regexp_filter(task, filter, fn, r)
  if string.find(filter, 'regexp:') then
    if not r['re_filter'] then
      local type,pat = string.match(filter, '(regexp:)(.+)')
      if type and pat then
        r['re_filter'] = regexp.create(pat)
      end
    end

    if not r['re_filter'] then
      rspamd_logger.errx(task, 'bad search filter: %s', filter)
    else
      local results = r['re_filter']:search(fn, false, true)
      if results then
        return results[1][2]
      else
        return nil
      end
    end
  end

  return fn
end

local function apply_content_filter(task, filter)
  if filter == 'body' then
    return {task:get_rawbody()}
  elseif filter == 'full' then
    return {task:get_content()}
  elseif filter == 'headers' then
    return {task:get_raw_headers()}
  elseif filter == 'text' then
    local ret = {}
    for _,p in ipairs(task:get_text_parts()) do
      table.insert(ret, p:get_content())
    end
    return ret
  elseif filter == 'rawtext' then
    local ret = {}
    for _,p in ipairs(task:get_text_parts()) do
      table.insert(ret, p:get_raw_content())
    end
    return ret
  elseif filter == 'oneline' then
    local ret = {}
    for _,p in ipairs(task:get_text_parts()) do
      table.insert(ret, p:get_content_oneline())
    end
    return ret
  else
    rspamd_logger.errx(task, 'bad search filter: %s', filter)
  end

  return {}
end

local multimap_filters = {
  from = apply_addr_filter,
  rcpt = apply_addr_filter,
  helo = apply_hostname_filter,
  symbol_options = apply_regexp_filter,
  header = apply_addr_filter,
  url = apply_url_filter,
  filename = apply_filename_filter,
  mempool = apply_regexp_filter,
  selector = apply_regexp_filter,
  hostname = apply_hostname_filter,
  --content = apply_content_filter, -- Content filters are special :(
}

local multimap_grammar

local function multimap_callback(task, rule)
  local pre_filter = rule['prefilter']

  local function match_element(r, value, callback)
   if not value then
      return false
    end

    local function redis_map_cb(err, data)
      if not err and type(data) ~= 'userdata' then
        callback(data)
      end
    end

    local ret = false

    if r['cdb'] then
      local srch = value
      if r['type'] == 'ip' then
        srch = value:to_string()
      end
      ret = r['cdb']:lookup(srch)
    elseif r['redis_key'] then
      local srch = {value}
      local cmd = 'HGET'
      if r['type'] == 'ip' or (r['type'] == 'received' and
        (r['filter'] == 'real_ip' or r['filter'] == 'from_ip' or not r['filter'])) then
        srch = {value:to_string()}
        cmd = 'HMGET'
        local maxbits = 128
        local minbits = 32
        if value:get_version() == 4 then
            maxbits = 32
            minbits = 8
        end
        for i=maxbits,minbits,-1 do
            local nip = value:apply_mask(i):to_string() .. "/" .. i
            table.insert(srch, nip)
        end
      end

      table.insert(srch, 1, r['redis_key'])
      ret = rspamd_redis_make_request(task,
        redis_params, -- connect params
        r['redis_key'], -- hash key
        false, -- is write
        redis_map_cb, --callback
        cmd, -- command
        srch -- arguments
      )

      return ret
    elseif r['radix'] then
      ret = r['radix']:get_key(value)
    elseif r['hash'] then
      ret = r['hash']:get_key(value)
    end

    if ret then
      if type(ret) == 'table' then
        for _,elt in ipairs(ret) do
          callback(elt)
        end

        ret = true
      else
        callback(ret)
      end
    end

    return ret
  end

  -- Parse result in form: <symbol>:<score>|<symbol>|<score>
  local function parse_ret(parse_rule, p_ret)
    if p_ret and type(p_ret) == 'string' then
      local lpeg = require "lpeg"

      if not multimap_grammar then
      local number = {}

        local digit = lpeg.R("09")
        number.integer =
        (lpeg.S("+-") ^ -1) *
                (digit   ^  1)

        -- Matches: .6, .899, .9999873
        number.fractional =
        (lpeg.P(".")   ) *
                (digit ^ 1)

        -- Matches: 55.97, -90.8, .9
        number.decimal =
        (number.integer *              -- Integer
                (number.fractional ^ -1)) +    -- Fractional
                (lpeg.S("+-") * number.fractional)  -- Completely fractional number

        local sym_start = lpeg.R("az", "AZ") + lpeg.S("_")
        local sym_elt = sym_start + lpeg.R("09")
        local symbol = sym_start * sym_elt ^0
        local symbol_cap = lpeg.Cg(symbol, 'symbol')
        local score_cap = lpeg.Cg(number.decimal, 'score')
        local symscore_cap = (symbol_cap * lpeg.P(":") * score_cap)
        local grammar = symscore_cap + symbol_cap + score_cap
        multimap_grammar = lpeg.Ct(grammar)
      end
      local tbl = multimap_grammar:match(p_ret)

      if tbl then
        local sym
        local score = 1.0

        if tbl['symbol'] then
          sym = tbl['symbol']
        end
        if tbl['score'] then
          score = tbl['score']
        end

        return true,sym,score
      else
        if p_ret ~= '' then
          rspamd_logger.infox(task, '%s: cannot parse string "%s"',
            parse_rule.symbol, p_ret)
        end

        return true,nil,1.0
      end
    elseif type(p_ret) == 'boolean' then
      return p_ret,nil,0.0
    end

    return false,nil,0.0
  end

  -- Match a single value for against a single rule
  local function match_rule(r, value)
    local function rule_callback(result)
      if result then
        if type(result) == 'table' then
          for _,rs in ipairs(result) do
            if type(rs) ~= 'userdata' then
              rule_callback(rs)
            end
          end
          return
        end
        local _,symbol,score = parse_ret(r, result)
        local forced = false
        if symbol then
          if r['symbols_set'] then
            if not r['symbols_set'][symbol] then
              rspamd_logger.infox(task, 'symbol %s is not registered for map %s, ' ..
                  'replace it with just %s',
                  symbol, r['symbol'], r['symbol'])
              symbol = r['symbol']
            end
          else
            forced = true
          end
        else
          symbol = r['symbol']
        end

        local opt = value_types[r['type']].get_value(value)
        if opt then
          task:insert_result(forced, symbol, score, opt)
        else
          task:insert_result(forced, symbol, score)
        end

        if pre_filter then
          if r['message_func'] then
            r['message'] = r.message_func(task, r['symbol'], opt)
          end
          if r['message'] then
            task:set_pre_result(r['action'], r['message'])
          else
            task:set_pre_result(r['action'], 'Matched map: ' .. r['symbol'])
          end
        end
      end
    end

    if r['filter'] or r['type'] == 'url' then
      local fn = multimap_filters[r['type']]

      if fn then
        value = fn(task, r['filter'], value, r)
      end
    end

    match_element(r, value, rule_callback)
  end

  -- Match list of values according to the field
  local function match_list(r, ls, fields)
    if ls then
      if fields then
        fun.each(function(e)
          local match = e[fields[1]]
          if match then
            if fields[2] then
              match = fields[2](match)
            end
            match_rule(r, match)
          end
        end, ls)
      else
        fun.each(function(e) match_rule(r, e) end, ls)
      end
    end
  end

  local function match_addr(r, addr)
    match_list(r, addr, {'addr'})

    if not r.filter then
      match_list(r, addr, {'domain'})
      match_list(r, addr, {'user'})
    end
  end

  local function match_url(r, url)
    match_rule(r, url)
  end

  local function match_hostname(r, hostname)
     match_rule(r, hostname)
  end

  local function match_filename(r, fn)
    match_rule(r, fn)
  end

  local function match_received_header(r, pos, total, h)
    local use_tld = false
    local filter = r['filter'] or 'real_ip'
    if filter:match('^tld:') then
      filter = filter:sub(5)
      use_tld = true
    end
    local v = h[filter]
    if v then
      local min_pos = tonumber(r['min_pos'])
      local max_pos = tonumber(r['max_pos'])
      if min_pos then
        if min_pos < 0 then
          if min_pos == -1 then
            if (pos ~= total) then
              return
            end
          else
            if pos <= (total - (min_pos*-1)) then
              return
            end
          end
        elseif pos < min_pos then
          return
        end
      end
      if max_pos then
        if max_pos < -1 then
          if (total - (max_pos*-1)) >= pos then
            return
          end
        elseif max_pos > 0 then
          if pos > max_pos then
            return
          end
        end
      end
      local match_flags = r['flags']
      local nmatch_flags = r['nflags']
      if match_flags or nmatch_flags then
        local got_flags = h['flags']
        if match_flags then
          for _, flag in ipairs(match_flags) do
            if not got_flags[flag] then return end
          end
        end
        if nmatch_flags then
          for _, flag in ipairs(nmatch_flags) do
            if got_flags[flag] then return end
          end
        end
      end
      if filter == 'real_ip' or filter == 'from_ip' then
        if type(v) == 'string' then
          v = rspamd_ip.from_string(v)
        end
        if v and v:is_valid() then
          match_rule(r, v)
        end
      else
        if use_tld and type(v) == 'string' then
          v = util.get_tld(v)
        end
        match_rule(r, v)
      end
    end
  end

  local function match_content(r)
    local data

    if r['filter'] then
      data = apply_content_filter(task, r['filter'], r)
    else
      data = {task:get_content()}
    end

    for _,v in ipairs(data) do
      match_rule(r, v)
    end
  end

  if rule['expression'] then
    local res,trace = rule['expression']:process_traced(task)

    if not res or res == 0 then
      lua_util.debugm(N, task, 'condition is false for %s', rule['symbol'])
      return
    else
      lua_util.debugm(N, task, 'condition is true for %s: %s', rule['symbol'],
        trace)
    end
  end

  local rt = rule['type']
  local process_rule_funcs = {
    dnsbl = function()
      local ip = task:get_from_ip()
      if ip:is_valid() then
        if rt == 'ip' then
          match_rule(rule, ip)
        else
          local to_resolve = ip_to_rbl(ip, rule['map'])

          local is_ok, results = rspamd_dns.request({
            type = "a",
            task = task,
            name = to_resolve,
          })

          lua_util.debugm(N, rspamd_config, 'resolve() finished: results=%1, is_ok=%2, to_resolve=%3', results, is_ok, to_resolve)

          if not is_ok and (results ~= 'requested record is not found' and results ~= 'no records with this name') then
            rspamd_logger.errx(task, 'error looking up %s: %s', to_resolve, results)
          elseif is_ok then
            task:insert_result(rule['symbol'], 1, rule['map'])
            if pre_filter then
              task:set_pre_result(rule['action'], 'Matched map: ' .. rule['symbol'])
            end
          end

        end
      end
    end,
    header = function()
      if type(rule['header']) == 'table' then
        for _,rh in ipairs(rule['header']) do
          local hv = task:get_header_full(rh)
          match_list(rule, hv, {'decoded'})
        end
      else
        local hv = task:get_header_full(rule['header'])
        match_list(rule, hv, {'decoded'})
      end
    end,
    rcpt = function()
      if task:has_recipients('smtp') then
        local rcpts = task:get_recipients('smtp')
        match_addr(rule, rcpts)
      elseif task:has_recipients('mime') then
        local rcpts = task:get_recipients('mime')
        match_addr(rule, rcpts)
      end
    end,
    from = function()
      if task:has_from('smtp') then
        local from = task:get_from('smtp')
        match_addr(rule, from)
      elseif task:has_from('mime') then
        local from = task:get_from('mime')
        match_addr(rule, from)
      end
    end,
    helo = function()
      local helo = task:get_helo()
      if helo then
        match_hostname(rule, helo)
      end
    end,
    url = function()
      if task:has_urls() then
        local msg_urls = task:get_urls()

        for _,url in ipairs(msg_urls) do
          match_url(rule, url)
        end
      end
    end,
    filename = function()
      local parts = task:get_parts()
      for _,p in ipairs(parts) do
        if p:is_archive() and not rule['skip_archives'] then
          local fnames = p:get_archive():get_files()

          for _,fn in ipairs(fnames) do
            match_filename(rule, fn)
          end
        end

        local fn = p:get_filename()
        if fn then
          match_filename(rule, fn)
        end
      end
    end,
    content = function()
      match_content(rule)
    end,
    hostname = function()
      local hostname = task:get_hostname()
      if hostname then
        match_hostname(rule, hostname)
      end
    end,
    asn = function()
      local asn = task:get_mempool():get_variable('asn')
      if asn then
        match_rule(rule, asn)
      end
    end,
    country = function()
      local country = task:get_mempool():get_variable('country')
      if country then
        match_rule(rule, country)
      end
    end,
    mempool = function()
      local var = task:get_mempool():get_variable(rule['variable'])
      if var then
        match_rule(rule, var)
      end
    end,
    symbol_options = function()
      local sym = task:get_symbol(rule['target_symbol'])
      if sym and sym[1].options then
        for _, o in ipairs(sym[1].options) do
          match_rule(rule, o)
        end
      end
    end,
    received = function()
      local hdrs = task:get_received_headers()
      if hdrs and hdrs[1] then
        if not rule['artificial'] then
          hdrs = fun.filter(function(h)
            return not h['flags']['artificial']
          end, hdrs):totable()
        end
        for pos, h in ipairs(hdrs) do
          match_received_header(rule, pos, #hdrs, h)
        end
      end
    end,
    selector = function()
      local elts = rule.selector(task)

      if elts then
        if type(elts) == 'table' then
          for _,elt in ipairs(elts) do
            match_rule(rule, elt)
          end
        else
          match_rule(rule, elts)
        end
      end
    end,
  }

  process_rule_funcs.ip = process_rule_funcs.dnsbl
  local f = process_rule_funcs[rt]
  if f then
    f()
  else
    rspamd_logger.errx(task, 'Unrecognised rule type: %s', rt)
  end
end

local function gen_multimap_callback(rule)
  return function(task)
    multimap_callback(task, rule)
  end
end

local function add_multimap_rule(key, newrule)
  local ret = false

  local function multimap_load_hash(rule)
    if rule['regexp'] then
      if rule['multi'] then
        rule['hash'] = rspamd_config:add_map ({
          url = rule['map'],
          description = rule['description'],
          type = 'regexp_multi'
        })
      else
        rule['hash'] = rspamd_config:add_map ({
          url = newrule['map'],
          description = newrule['description'],
          type = 'regexp'
        })
      end
    elseif rule['glob'] then
      if rule['multi'] then
        rule['hash'] = rspamd_config:add_map ({
          url = rule['map'],
          description = rule['description'],
          type = 'glob_multi'
        })
      else
        rule['hash'] = rspamd_config:add_map ({
          url = rule['map'],
          description = rule['description'],
          type = 'glob'
        })
      end
    else
      rule['hash'] = rspamd_config:add_map ({
        url = rule['map'],
        description = rule['description'],
        type = 'hash'
      })
    end
  end

  if newrule['message_func'] then
    newrule['message_func'] = assert(load(newrule['message_func']))()
  end
  if newrule['url'] and not newrule['map'] then
    newrule['map'] = newrule['url']
  end
  if not newrule['map'] then
    rspamd_logger.errx(rspamd_config, 'incomplete rule, missing map')
    return nil
  end
  if not newrule['symbol'] and key then
    newrule['symbol'] = key
  elseif not newrule['symbol'] then
    rspamd_logger.errx(rspamd_config, 'incomplete rule, missing symbol')
    return nil
  end
  if not newrule['description'] then
    newrule['description'] = string.format('multimap, type %s: %s', newrule['type'],
      newrule['symbol'])
  end
  if newrule['type'] == 'mempool' and not newrule['variable'] then
    rspamd_logger.errx(rspamd_config, 'mempool map requires variable')
    return nil
  end
  if newrule['type'] == 'selector' then
    if not newrule['selector'] then
      rspamd_logger.errx(rspamd_config, 'selector map requires selector definition')
      return nil
    else
      local selector = lua_selectors.create_selector_closure(
          rspamd_config, newrule['selector'], newrule['delimiter'] or "")

      if not selector then
        rspamd_logger.errx(rspamd_config, 'selector map has invalid selector: "%s", symbol: %s',
            newrule['selector'], newrule['symbol'])
        return nil
      end

      newrule.selector = selector
    end
  end
  -- Check cdb flag
  if type(newrule['map']) == 'string' and string.find(newrule['map'], '^cdb://.*$') then
    newrule['cdb'] = cdb.create(newrule['map'])
    if newrule['cdb'] then
      ret = true
    else
      rspamd_logger.warnx(rspamd_config, 'Cannot add rule: map doesn\'t exists: %1',
          newrule['map'])
    end
  elseif type(newrule['map']) == 'string' and string.find(newrule['map'], '^redis://.*$') then
    if not redis_params then
      rspamd_logger.infox(rspamd_config, 'no redis servers are specified, ' ..
        'cannot add redis map %s: %s', newrule['symbol'], newrule['map'])
      return nil
    end

    newrule['redis_key'] = string.match(newrule['map'], '^redis://(.*)$')

    if newrule['redis_key'] then
      ret = true
    end
  else
    if type(newrule['map']) == 'string' then
      local map = urls[newrule['map']]
      if map and map['regexp'] == newrule['regexp'] and
          map['glob'] == newrule['glob'] then
        if newrule['type'] == 'ip' then
          newrule['radix'] = map['map']
        else
          newrule['hash'] = map['map']
        end
        rspamd_logger.infox(rspamd_config, 'reuse url for %s: "%s"',
          newrule['symbol'], newrule['map'])
        ret = true
      end
    end
    if not ret then
      if newrule['type'] == 'ip' then
        newrule['radix'] = rspamd_config:add_map ({
          url = newrule['map'],
          description = newrule['description'],
          type = 'radix'
        })
        if newrule['radix'] then
          ret = true
          if type(newrule['map']) == 'string' then
            urls[newrule['map']] = {
              type = 'ip',
              map = newrule['radix'],
              regexp = false
            }
          end
        else
          rspamd_logger.warnx(rspamd_config, 'Cannot add rule: map doesn\'t exists: %1',
            newrule['map'])
        end
      elseif newrule['type'] == 'received' then
        if type(newrule['flags']) == 'table' and newrule['flags'][1] then
          newrule['flags'] = newrule['flags']
        elseif type(newrule['flags']) == 'string' then
          newrule['flags'] = {newrule['flags']}
        end
        if type(newrule['nflags']) == 'table' and newrule['nflags'][1] then
          newrule['nflags'] = newrule['nflags']
        elseif type(newrule['nflags']) == 'string' then
          newrule['nflags'] = {newrule['nflags']}
        end
        local filter = newrule['filter'] or 'real_ip'
        if filter == 'real_ip' or filter == 'from_ip' then
          newrule['radix'] = rspamd_config:add_map ({
            url = newrule['map'],
            description = newrule['description'],
            type = 'radix'
          })
          if newrule['radix'] then
            ret = true
          end
        else
          multimap_load_hash(newrule)

          if newrule['hash'] then
            ret = true
            if type(newrule['map']) == 'string' then
              urls[newrule['map']] = {
                type = newrule['type'],
                map = newrule['hash'],
                regexp = newrule['regexp']
              }
            end
          else
            rspamd_logger.warnx(rspamd_config, 'Cannot add rule: map doesn\'t exists: %1',
              newrule['map'])
          end
        end
      elseif newrule['type'] == 'header'
          or newrule['type'] == 'rcpt'
          or newrule['type'] == 'from'
          or newrule['type'] == 'helo'
          or newrule['type'] == 'symbol_options'
          or newrule['type'] == 'filename'
          or newrule['type'] == 'url'
          or newrule['type'] == 'content'
          or newrule['type'] == 'hostname'
          or newrule['type'] == 'asn'
          or newrule['type'] == 'country'
          or newrule['type'] == 'mempool'
          or newrule['type'] == 'selector'then

        multimap_load_hash(newrule)

        if newrule['hash'] then
          ret = true
          if type(newrule['map']) == 'string' then
            urls[newrule['map']] = {
              type = newrule['type'],
              map = newrule['hash'],
              regexp = newrule['regexp']
            }
          end
        else
          rspamd_logger.warnx(rspamd_config, 'Cannot add rule: map doesn\'t exists: %1',
            newrule['map'])
        end
      elseif newrule['type'] == 'dnsbl' then
        ret = true
      end
    end
  end

  if newrule['action'] then
    newrule['prefilter'] = true
  else
    newrule['prefilter'] = false
  end

  if ret then
    if newrule['type'] == 'symbol_options' then
      rspamd_config:register_dependency(newrule['symbol'], newrule['target_symbol'])
    end
    if newrule['require_symbols'] and not newrule['prefilter'] then
      local atoms = {}

      local function parse_atom(str)
        local atom = table.concat(fun.totable(fun.take_while(function(c)
          if string.find(', \t()><+!|&\n', c) then
            return false
          end
          return true
        end, fun.iter(str))), '')
        table.insert(atoms, atom)
        return atom
      end

      local function process_atom(atom, task)
        local f_ret = task:has_symbol(atom)
        lua_util.debugm(N, rspamd_config, 'check for symbol %s: %s', atom, f_ret)

        if f_ret then
          return 1
        end

        return 0
      end

      local expression = rspamd_expression.create(newrule['require_symbols'],
        {parse_atom, process_atom}, rspamd_config:get_mempool())
      if expression then
        newrule['expression'] = expression

        fun.each(function(v)
          lua_util.debugm(N, rspamd_config, 'add dependency %s -> %s',
            newrule['symbol'], v)
          rspamd_config:register_dependency(newrule['symbol'], v)
        end, atoms)
      end
    end
    return newrule
  end

  return nil
end

-- Registration
local opts = rspamd_config:get_all_opt(N)
if opts and type(opts) == 'table' then
  redis_params = rspamd_parse_redis_server(N)
  for k,m in pairs(opts) do
    if type(m) == 'table' and m['type'] then
      local rule = add_multimap_rule(k, m)
      if not rule then
        rspamd_logger.errx(rspamd_config, 'cannot add rule: "'..k..'"')
      else
        rspamd_logger.infox(rspamd_config, 'added multimap rule: %s (%s)',
            k, rule.type)
        table.insert(rules, rule)
      end
    end
  end
  -- add fake symbol to check all maps inside a single callback
  fun.each(function(rule)
    local id = rspamd_config:register_symbol({
      type = 'normal',
      name = rule['symbol'],
      callback = gen_multimap_callback(rule),
    })
    if rule['symbols'] then
      -- Find allowed symbols by this map
      rule['symbols_set'] = {}
      fun.each(function(s)
        rspamd_config:register_symbol({
          type = 'virtual',
          name = s,
          parent = id
        })
        rule['symbols_set'][s] = 1
      end, rule['symbols'])
    end
    if rule['score'] then
      -- Register metric symbol
      rule.name = rule.symbol
      rule.description = rule.description or 'multimap symbol'
      rule.group = rule.group or N

      rspamd_config:set_metric_symbol(rule)
    end
  end,
  fun.filter(function(r) return not r['prefilter'] end, rules))

  fun.each(function(r)
    rspamd_config:register_symbol({
      type = 'prefilter',
      name = r['symbol'],
      callback = gen_multimap_callback(r),
    })
  end,
  fun.filter(function(r) return r['prefilter'] end, rules))

  if #rules == 0 then
    lua_util.disable_module(N, "config")
  end
end
