Name
msys.av.scan — Perform a virus scan using the named engine
Synopsis
msys.av.scan(av_engine_name, msg, validate_context);
av_engine_name: string, optional msg: userdata, ec_message type, optional validate_context: userdata, validate_context type, optional
Description
Use this function with AV engines that depend on the AV module, such as the clamav module.
This function performs a virus scan. The scan is done using the specified engine or, if no engine is specified, any installed engines that are supported by the AV module. If a virus is detected by an engine, the function will skip the remaining engines and return. For a list of these engines, see “antivirus – Antivirus”.
Enable this function with the statement require('msys.av');.
This function takes the following parameters:
-
av_engine_name– optional engine name -
msg– optional message (msys.core:_ec_message) -
validate_context– optional validation context
If the msg and/or validate_context parameters are omitted, they will be inferred from the calling environment, if possible. If no message can be inferred, this function will raise an error.
This function returns four values:
-
The scan status , which is one of the following values:
-
msys.av.EC_AV_PART_IS_CONTAINER – A container was passed to
msys.av.scan. -
msys.av.EC_AV_NAME_TOO_LONG –
av_engine_nameis longer than 40 characters. -
msys.av.EC_AV_NO_ENGINE – No AV engine is configured.
-
msys.av.EC_AV_NOT_SUITABLE_FOR_STREAMING – AV engine cannot scan the message that was passed in as a stream.
-
msys.av.EC_AV_ERROR – A runtime error occurred. For clamav-specific information, see “clamav Runtime Usage”.
-
msys.av.EC_AV_CLEAN – Meaning of this status depends on the AV engine.
-
msys.av.EC_AV_INFECTED – Meaning of this status depends on the AV engine. For engine-specific information, see “Context Variables” and “clamav Runtime Usage”.
-
msys.av.EC_AV_UNSCANNABLE – Message could not be scanned.
-
-
An informational string , which typically contains the virus name; the precise contents of this string depend on the engine.
-
The name of the AV engine that detected the virus or
nilif no virus was detected. -
The engine scan code or
nilif no engine scan code is available. The scan code returned is specific to the engine reporting the error. For engine-specific information, see “Context Variables” and “clamav Runtime Usage”.
require("msys.av"); local mod = {}; function mod:validate_data(msg, accept, vctx) local rc local result local eng local s_code rc, result, eng, s_code = msys.av.scan("clamav", msg, vctx); print ("rc: ", rc, map_to_symbol(rc), " result: ", result, " engine: ", eng, " scan code: ", s_code) if rc == msys.av.EC_AV_INFECTED then vctx:set_code(550, "The mail contains virus: " .. result) return msys.core.VALIDATE_DONE; end return msys.core.VALIDATE_CONT; end local function map_to_symbol(rc) if rc == msys.av.EC_AV_PART_IS_CONTAINER then return "EC_AV_PART_IS_CONTAINER" elseif rc == msys.av.EC_AV_NAME_TOO_LONG then return "EC_AV_NAME_TOO_LONG" elseif rc == msys.av.EC_AV_NO_ENGINE then return "EC_AV_NO_ENGINE" elseif rc == msys.av.EC_AV_NOT_SUITABLE_FOR_STREAMING then return "EC_AV_NOT_SUITABLE_FOR_STREAMING" elseif rc == msys.av.EC_AV_ERROR then return "EC_AV_ERROR" elseif rc == msys.av.EC_AV_CLEAN then return "EC_AV_CLEAN" elseif rc == msys.av.EC_AV_INFECTED then return "EC_AV_INFECTED" elseif rc == msys.av.EC_AV_UNSCANNABLE then return "EC_AV_UNSCANNABLE" else return "UNKNOWN" end end msys.registerModule("test_av", mod);