123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216 |
- --[[
- Copyright (c) 2022, Vsevolod Stakhov <vsevolod@rspamd.com>
- Copyright (c) 2019, Carsten Rosenberg <c.rosenberg@heinlein-support.de>
-
- 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 spamassassin
- -- This module contains spamd 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 N = 'spamassassin'
-
- local function spamassassin_config(opts)
-
- local spamassassin_conf = {
- N = N,
- scan_mime_parts = false,
- scan_text_mime = false,
- scan_image_mime = false,
- default_port = 783,
- timeout = 15.0,
- log_clean = false,
- retransmits = 2,
- cache_expire = 3600, -- expire redis in one hour
- symbol = "SPAMD",
- message = '${SCANNER}: Spamassassin bulk message found: "${VIRUS}"',
- detection_category = "spam",
- default_score = 1,
- action = false,
- extended = false,
- symbol_type = 'postfilter',
- dynamic_scan = true,
- }
-
- spamassassin_conf = lua_util.override_defaults(spamassassin_conf, opts)
-
- if not spamassassin_conf.prefix then
- spamassassin_conf.prefix = 'rs_' .. spamassassin_conf.name .. '_'
- end
-
- if not spamassassin_conf.log_prefix then
- if spamassassin_conf.name:lower() == spamassassin_conf.type:lower() then
- spamassassin_conf.log_prefix = spamassassin_conf.name
- else
- spamassassin_conf.log_prefix = spamassassin_conf.name .. ' (' .. spamassassin_conf.type .. ')'
- end
- end
-
- if not spamassassin_conf.servers then
- rspamd_logger.errx(rspamd_config, 'no servers defined')
-
- return nil
- end
-
- spamassassin_conf.upstreams = upstream_list.create(rspamd_config,
- spamassassin_conf.servers,
- spamassassin_conf.default_port)
-
- if spamassassin_conf.upstreams then
- lua_util.add_debug_alias('external_services', spamassassin_conf.N)
- return spamassassin_conf
- end
-
- rspamd_logger.errx(rspamd_config, 'cannot parse servers %s',
- spamassassin_conf.servers)
- return nil
- end
-
- local function spamassassin_check(task, content, digest, rule)
- local function spamassassin_check_uncached ()
- local upstream = rule.upstreams:get_upstream_round_robin()
- local addr = upstream:get_addr()
- local retransmits = rule.retransmits
-
- -- Build the spamd query
- -- https://svn.apache.org/repos/asf/spamassassin/trunk/spamd/PROTOCOL
- local request_data = {
- "HEADERS SPAMC/1.5\r\n",
- "User: root\r\n",
- "Content-length: ".. #content .. "\r\n",
- "\r\n",
- content,
- }
-
- local function spamassassin_callback(err, data)
-
- local function spamassassin_requery(error)
- -- 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
-
- lua_util.debugm(rule.N, task, '%s: Request Error: %s - retries left: %s',
- rule.log_prefix, error, retransmits)
-
- -- Select a different upstream!
- upstream = rule.upstreams:get_upstream_round_robin()
- addr = upstream:get_addr()
-
- lua_util.debugm(rule.N, task, '%s: retry IP: %s:%s',
- rule.log_prefix, addr, addr:get_port())
-
- tcp.request({
- task = task,
- host = addr:to_string(),
- port = addr:get_port(),
- timeout = rule['timeout'],
- data = request_data,
- callback = spamassassin_callback,
- })
- else
- rspamd_logger.errx(task, '%s: failed to scan, maximum retransmits '..
- 'exceed - err: %s', rule.log_prefix, error)
- common.yield_result(task, rule, 'failed to scan and retransmits exceed: ' .. error, 0.0, 'fail')
- end
- end
-
- if err then
-
- spamassassin_requery(err)
-
- else
- -- Parse the response
- if upstream then upstream:ok() end
-
- --lua_util.debugm(rule.N, task, '%s: returned result: %s', rule.log_prefix, data)
-
- --[[
- patterns tested against Spamassassin 3.4.6
-
- X-Spam-Status: No, score=1.1 required=5.0 tests=HTML_MESSAGE,MIME_HTML_ONLY,
- TVD_RCVD_SPACE_BRACKET,UNPARSEABLE_RELAY autolearn=no
- autolearn_force=no version=3.4.6
- ]] --
- local header = string.gsub(tostring(data), "[\r\n]+[\t ]", " ")
- --lua_util.debugm(rule.N, task, '%s: returned header: %s', rule.log_prefix, header)
-
- local symbols = ""
- local spam_score = 0
- for s in header:gmatch("[^\r\n]+") do
- if string.find(s, 'X%-Spam%-Status: %S+, score') then
- local pattern_symbols = "X%-Spam%-Status: %S+, score%=([%-%d%.]+)%s.*tests%=(.*,?)(%s*%S+)%sautolearn.*"
- spam_score = string.gsub(s, pattern_symbols, "%1")
- symbols = string.gsub(s, pattern_symbols, "%2%3")
- symbols = string.gsub(symbols, "%s", "")
- end
- end
-
- lua_util.debugm(rule.N, task, '%s: spam_score: %s, symbols: %s, int spam_score: |%s|, type spam_score: |%s|',
- rule.log_prefix, spam_score, symbols, tonumber(spam_score), type(spam_score))
-
- if tonumber(spam_score) > 0 and #symbols > 0 and symbols ~= "none" then
-
- if rule.extended == false then
- common.yield_result(task, rule, symbols, spam_score)
- common.save_cache(task, digest, rule, symbols, spam_score)
- else
- local symbols_table = lua_util.str_split(symbols, ",")
- lua_util.debugm(rule.N, task, '%s: returned symbols as table: %s', rule.log_prefix, symbols_table)
-
- common.yield_result(task, rule, symbols_table, spam_score)
- common.save_cache(task, digest, rule, symbols_table, spam_score)
- end
- else
- common.save_cache(task, digest, rule, 'OK')
- common.log_clean(task, rule, 'no spam detected - spam score: ' .. spam_score .. ', symbols: ' .. symbols)
- end
- end
- end
-
- tcp.request({
- task = task,
- host = addr:to_string(),
- port = addr:get_port(),
- timeout = rule['timeout'],
- data = request_data,
- callback = spamassassin_callback,
- })
- end
-
- if common.condition_check_and_continue(task, content, rule, digest, spamassassin_check_uncached) then
- return
- else
- spamassassin_check_uncached()
- end
-
- end
-
- return {
- type = {N,'spam', 'scanner'},
- description = 'spamassassin spam scanner',
- configure = spamassassin_config,
- check = spamassassin_check,
- name = N
- }
|