[Rework] Lua_scanners: Further library split

1 files changed, 167 insertions, 0 deletions

diff --git a/lualib/lua_scanners/clamav.lua b/lualib/lua_scanners/clamav.lua
new file mode 100644
index 000000000..26d5e9c81
--- /dev/null
+++ b/lualib/lua_scanners/clamav.lua
@@ -0,0 +1,167 @@
+--[[
+Copyright (c) 2018, 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.
+]]--
+
+--[[[
+-- @module clamav
+-- This module contains clamav access functions
+--]]
+
+local lua_util = require "lua_util"
+local tcp = require "rspamd_tcp"
+local upstream_list = require "rspamd_upstream_list"
+local rspamd_util = require "rspamd_util"
+local rspamd_logger = require "rspamd_logger"
+local common = require "lua_scanners/common"
+
+local N = "antivirus"
+
+local default_message = '${SCANNER}: virus found: "${VIRUS}"'
+
+local function clamav_config(opts)
+  local clamav_conf = {
+    scan_mime_parts = true;
+    scan_text_mime = false;
+    scan_image_mime = false;
+    default_port = 3310,
+    log_clean = false,
+    timeout = 15.0, -- FIXME: this will break task_timeout!
+    retransmits = 2,
+    cache_expire = 3600, -- expire redis in one hour
+    message = default_message,
+  }
+
+  for k,v in pairs(opts) do
+    clamav_conf[k] = v
+  end
+
+  if not clamav_conf.prefix then
+    clamav_conf.prefix = 'rs_cl'
+  end
+
+  if not clamav_conf['servers'] then
+    rspamd_logger.errx(rspamd_config, 'no servers defined')
+
+    return nil
+  end
+
+  clamav_conf['upstreams'] = upstream_list.create(rspamd_config,
+      clamav_conf['servers'],
+      clamav_conf.default_port)
+
+  if clamav_conf['upstreams'] then
+    return clamav_conf
+  end
+
+  rspamd_logger.errx(rspamd_config, 'cannot parse servers %s',
+      clamav_conf['servers'])
+  return nil
+end
+
+local function clamav_check(task, content, digest, rule)
+  local function clamav_check_uncached ()
+    local upstream = rule.upstreams:get_upstream_round_robin()
+    local addr = upstream:get_addr()
+    local retransmits = rule.retransmits
+    local header = rspamd_util.pack("c9 c1 >I4", "zINSTREAM", "\0",
+        #content)
+    local footer = rspamd_util.pack(">I4", 0)
+
+    local function clamav_callback(err, data)
+      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 [%s]: retry IP: %s', rule['symbol'], rule['type'], addr)
+
+          tcp.request({
+            task = task,
+            host = addr:to_string(),
+            port = addr:get_port(),
+            timeout = rule['timeout'],
+            callback = clamav_callback,
+            data = { header, content, footer },
+            stop_pattern = '\0'
+          })
+        else
+          rspamd_logger.errx(task, '%s [%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
+        upstream:ok()
+        data = tostring(data)
+        local cached
+        lua_util.debugm(N, task, '%s [%s]: got reply: %s', rule['symbol'], rule['type'], data)
+        if data == 'stream: OK' then
+          cached = 'OK'
+          if rule['log_clean'] then
+            rspamd_logger.infox(task, '%s [%s]: message or mime_part is clean', rule['symbol'], rule['type'])
+          else
+            lua_util.debugm(N, task, '%s [%s]: message or mime_part is clean', rule['symbol'], rule['type'])
+          end
+        else
+          local vname = string.match(data, 'stream: (.+) FOUND')
+          if vname then
+            common.yield_result(task, rule, vname, N)
+            cached = vname
+          else
+            rspamd_logger.errx(task, 'unhandled response: %s', data)
+            task:insert_result(rule['symbol_fail'], 0.0, 'unhandled response')
+          end
+        end
+        if cached then
+          common.save_av_cache(task, digest, rule, cached, N)
+        end
+      end
+    end
+
+    tcp.request({
+      task = task,
+      host = addr:to_string(),
+      port = addr:get_port(),
+      timeout = rule['timeout'],
+      callback = clamav_callback,
+      data = { header, content, footer },
+      stop_pattern = '\0'
+    })
+  end
+
+  if common.need_av_check(task, content, rule) then
+    if common.check_av_cache(task, digest, rule, clamav_check_uncached, N) then
+      return
+    else
+      clamav_check_uncached()
+    end
+  end
+end
+
+return {
+  type = 'antivirus',
+  description = 'clamav antivirus',
+  configure = clamav_config,
+  check = clamav_check,
+  name = 'clamav'
+}
\ No newline at end of file