From 9b806e7bc55b2eeb87a57eb0a81b002e4cb82912 Mon Sep 17 00:00:00 2001 From: Vsevolod Stakhov Date: Thu, 3 Jan 2019 10:19:22 +0000 Subject: [PATCH] [Feature] Add pyzor support (by crosenberg) --- lualib/lua_scanners/pyzor.lua | 215 ++++++++++++++++++++++++++++++++++ 1 file changed, 215 insertions(+) create mode 100644 lualib/lua_scanners/pyzor.lua diff --git a/lualib/lua_scanners/pyzor.lua b/lualib/lua_scanners/pyzor.lua new file mode 100644 index 000000000..4bca6ace7 --- /dev/null +++ b/lualib/lua_scanners/pyzor.lua @@ -0,0 +1,215 @@ +--[[ +Copyright (c) 2018, Carsten Rosenberg +Copyright (c) 2018, Vsevolod Stakhov + +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. +]]-- + +--[[[ +-- @module pyzor +-- This module contains pyzor access functions +--]] + +local lua_util = require "lua_util" +local tcp = require "rspamd_tcp" +local upstream_list = require "rspamd_upstream_list" +local rspamd_logger = require "rspamd_logger" +local common = require "lua_scanners/common" +local ucl = require "ucl" + +local N = 'pyzor' +local categories = {'pyzor','bulk', 'hash', 'scanner'} + +local function pyzor_config(opts) + + local pyzor_conf = { + text_part_min_words = 2, + default_port = 5953, + timeout = 15.0, + log_clean = false, + retransmits = 2, + detection_category = "hash", + cache_expire = 7200, -- expire redis in one hour + message = '${SCANNER}: Pyzor bulk message found: "${VIRUS}"', + default_score = 1, + action = false, + } + + pyzor_conf = lua_util.override_defaults(pyzor_conf, opts) + + if not pyzor_conf.prefix then + pyzor_conf.prefix = 'rext_' .. N .. '_' + end + + if not pyzor_conf.log_prefix then + pyzor_conf.log_prefix = N .. ' (' .. pyzor_conf.detection_category .. ')' + end + + if not pyzor_conf['servers'] then + rspamd_logger.errx(rspamd_config, 'no servers defined') + + return nil + end + + pyzor_conf['upstreams'] = upstream_list.create(rspamd_config, + pyzor_conf['servers'], + pyzor_conf.default_port) + + if pyzor_conf['upstreams'] then + lua_util.add_debug_alias('external_services', N) + return pyzor_conf + end + + rspamd_logger.errx(rspamd_config, 'cannot parse servers %s', + pyzor_conf['servers']) + return nil +end + +local function pyzor_check(task, content, digest, rule) + local function pyzor_check_uncached () + local upstream = rule.upstreams:get_upstream_round_robin() + local addr = upstream:get_addr() + local retransmits = rule.retransmits + + local function pyzor_callback(err, data, conn) + + if err then + + -- set current upstream to fail because an error occurred + upstream:fail() + + -- retry with another upstream until retransmits exceeds + if retransmits > 0 then + + retransmits = retransmits - 1 + + -- Select a different upstream! + upstream = rule.upstreams:get_upstream_round_robin() + addr = upstream:get_addr() + + lua_util.debugm(N, task, '%s: retry IP: %s:%s err: %s', + rule.log_prefix, addr, addr:get_port(), err) + + tcp.request({ + task = task, + host = addr:to_string(), + port = addr:get_port(), + timeout = rule['timeout'], + shutdown = true, + data = { "CHECK\n" , content }, + callback = pyzor_callback, + }) + else + rspamd_logger.errx(task, '%s: failed to scan, maximum retransmits exceed', + rule['symbol'], rule['type']) + task:insert_result(rule['symbol_fail'], 0.0, + 'failed to scan and retransmits exceed') + end + else + -- Parse the response + if upstream then upstream:ok() end + + lua_util.debugm(N, task, '%s: returned data: %s', rule.log_prefix, tostring(data)) + local ucl_parser = ucl.parser() + local ok, py_err = ucl_parser:parse_string(tostring(data)) + if not ok then + rspamd_logger.errx(task, "error parsing response: %s", py_err) + return + end + + local resp = ucl_parser:get_object() + local whitelisted = tonumber(resp["WL-Count"]) + local reported = tonumber(resp["Count"]) + + --rspamd_logger.infox(task, "%s - count=%s wl=%s", addr:to_string(), reported, whitelisted) + + --[[ + @todo: Implement math function to calc the score dynamically based on return values. + Maybe check spamassassin implementation. + ]] -- + local entries = reported - whitelisted + + local weight = 0 + + if entries >= 100 then + weight = 1.5 + elseif entries >= 25 then + weight = 1.25 + elseif entries >= 5 then + weight = 1.0 + elseif entries >= 1 and whitelisted == 0 then + weight = 0.2 + end + + if whitelisted >= 100 then + weight = weight - 1.5 + elseif whitelisted >= 25 then + weight = weight - 1.25 + elseif whitelisted >= 5 then + weight = weight - 1.0 + elseif whitelisted >= 1 then + weight = weight - 0.2 + end + + local info = string.format("count=%d wl=%d", reported, whitelisted) + local threat_string = string.format("bl_%d_wl_%d", reported, whitelisted) + + if weight > 0 then + lua_util.debugm(N, task, '%s: returned result is spam - info: %s', rule.log_prefix, info) + common.yield_result(task, rule, threat_string, N, weight) + common.save_av_cache(task, digest, rule, threat_string, N) + else + if rule.log_clean then + rspamd_logger.infox(task, '%s: clean, returned result is ham - info: %s', rule.log_prefix, info) + else + lua_util.debugm(N, task, '%s: returned result is ham - info: %s', rule.log_prefix, info) + end + common.save_av_cache(task, digest, rule, 'OK', N) + end + + end + end + + if common.text_parts_min_words(task, rule.text_part_min_words) then + rspamd_logger.infox(task, '%s: #words is less then text_part_min_words: %s', + rule.log_prefix, rule.text_part_min_words) + return + end + + tcp.request({ + task = task, + host = addr:to_string(), + port = addr:get_port(), + timeout = rule.timeout, + shutdown = true, + data = { "CHECK\n" , content }, + callback = pyzor_callback, + }) + end + if common.need_av_check(task, content, rule, N) then + if common.check_av_cache(task, digest, rule, pyzor_check_uncached, N) then + return + else + pyzor_check_uncached() + end + end +end + + +return { + type = categories, + description = 'pyzor bulk scanner', + configure = pyzor_config, + check = pyzor_check, + name = 'pyzor' +} \ No newline at end of file -- 2.39.5