ClamAV 之 Clamd.conf 配置文件參數文檔
#Time: 2020/03/14
#Author: Xiaohong
#運行環境: OS: Raspberry PI4
通過 man clamd.conf 獲取如下 Clamd.conf 配置文件參數文檔
NAME
clamd.conf - Configuration file for Clam AntiVirus Daemon
DESCRIPTION
clamd.conf configures the Clam AntiVirus daemon, clamd(8).
FILE FORMAT
The file consists of comments and options with arguments. Each line which starts with a hash (#) symbol is ig‐
nored by the parser. Options and arguments are case sensitive and of the form Option Argument. The arguments are
of the following types:
BOOL Boolean value (yes/no or true/false or 1/0).
STRING String without blank characters.
SIZE Size in bytes. You can use 'M' or 'm' modifiers for megabytes and 'K' or 'k' for kilobytes. To specify
the size in bytes just don't use modifiers.
NUMBER Unsigned integer.
DIRECTIVES
When some option is not used (commented out or not included in the configuration file at all) clamd takes a de‐
fault action.
Example
If this option is set clamd will not run.
LogFile STRING
Save all reports to a log file.
Default: disabled
LogFileUnlock BOOL
By default the log file is locked for writing and only a single daemon process can write to it. This op‐
tion disables the lock.
Default: no
LogFileMaxSize SIZE
Maximum size of the log file.
Value of 0 disables the limit.
Default: 1048576
LogTime BOOL
Log time for each message.
Default: no
LogClean BOOL
Log all clean files.
Useful in debugging but drastically increases the log size.
Default: no
LogSyslog BOOL
Use the system logger (can work together with LogFile).
Default: no
LogFacility STRING
Type of syslog messages
Please refer to 'man syslog' for facility names.
Default: LOG_LOCAL6
LogVerbose BOOL
Enable verbose logging.
Default: no
LogRotate BOOL
Rotate log file. Requires LogFileMaxSize option set prior to this option.
Default: no
ExtendedDetectionInfo BOOL
Log additional information about the infected file, such as its size and hash, together with the virus
name.
Default: no
PidFile STRING
Save the process identifier of a listening daemon (main thread) to a specified file.
Default: disabled
TemporaryDirectory STRING
This option allows you to change the default temporary directory.
Default: system specific (usually /tmp or /var/tmp).
DatabaseDirectory STRING
This option allows you to change the default database directory. If you enable it, please make sure it
points to the same directory in both clamd and freshclam.
Default: defined at configuration (/usr/local/share/clamav)
OfficialDatabaseOnly BOOL
Only load the official signatures published by the ClamAV project.
Default: no
LocalSocket STRING
Path to a local (Unix) socket the daemon will listen on.
Default: disabled
LocalSocketGroup STRING
Sets the group ownership on the unix socket.
Default: the primary group of the user running clamd
LocalSocketMode STRING
Sets the permissions on the unix socket to the specified mode.
Default: socket is world readable and writable
FixStaleSocket BOOL
Remove stale socket after unclean shutdown.
Default: yes
TCPSocket NUMBER
TCP port number the daemon will listen on.
Default: disabled
TCPAddr STRING
By default clamd binds to INADDR_ANY.
This option allows you to restrict the TCP address and provide some degree of protection from the outside
world. This option can be specified multiple times in order to listen on multiple IPs. IPv6 is now sup‐
ported.
Default: disabled
MaxConnectionQueueLength NUMBER
Maximum length the queue of pending connections may grow to.
Default: 200
StreamMaxLength SIZE
Close the STREAM session when the data size limit is exceeded.
The value should match your MTA's limit for the maximum attachment size.
Default: 25M
StreamMinPort NUMBER
The STREAM command uses an FTP-like protocol.
This option sets the lower boundary for the port range.
Default: 1024
StreamMaxPort NUMBER
This option sets the upper boundary for the port range.
Default: 2048
MaxThreads NUMBER
Maximum number of threads running at the same time.
Default: 10
ReadTimeout NUMBER
This option specifies the time (in seconds) after which clamd should timeout if a client doesn't provide
any data.
Default: 120
CommandReadTimeout NUMBER
This option specifies the time (in seconds) after which clamd should timeout if a client doesn't provide
any initial command after connecting. The default is set to 30 to avoid timeouts with TCP sockets when
processing large messages. If using a Unix socket, the value can be changed to 5. Note: the timeout for
subsequents commands, and/or data chunks is specified by ReadTimeout.
Default: 30
SendBufTimeout NUMBER
This option specifies how long to wait (in milliseconds) if the send buffer is full. Keep this value low
to prevent clamd hanging.
Default: 500
MaxQueue NUMBER
Maximum number of queued items (including those being processed by MaxThreads threads). It is recom‐
mended to have this value at least twice MaxThreads if possible.
WARNING: you shouldn't increase this too much to avoid running out of file descriptors, the following
condition should hold: MaxThreads*MaxRecursion + MaxQueue - MaxThreads + 6 < RLIMIT_NOFILE.
RLIMIT_NOFILE is the maximum number of open file descriptors (usually 1024), set by ulimit -n.
Default: 100
IdleTimeout NUMBER
This option specifies how long (in seconds) the process should wait for a new job.
Default: 30
ExcludePath REGEX
Don't scan files and directories matching REGEX. This directive can be used multiple times.
Default: disabled
MaxDirectoryRecursion NUMBER
Maximum depth directories are scanned at.
Default: 15
FollowDirectorySymlinks BOOL
Follow directory symlinks.
Default: no
CrossFilesystems BOOL
Scan files and directories on other filesystems.
Default: yes
FollowFileSymlinks BOOL
Follow regular file symlinks.
Default: no
SelfCheck NUMBER
This option specifies the time intervals (in seconds) in which clamd should perform a database check.
Default: 600
VirusEvent COMMAND
Execute a command when a virus is found. In the command string %v will be replaced with the virus name.
Additionally, two environment variables will be defined: $CLAM_VIRUSEVENT_FILENAME and $CLAM_VIRUSEV‐
ENT_VIRUSNAME.
Default: disabled
ExitOnOOM BOOL
Stop daemon when libclamav reports out of memory condition.
Default: no
AllowAllMatchScan BOOL
Permit use of the ALLMATCHSCAN command.
Default: yes
Foreground BOOL
Don't fork into background.
Default: no
Debug BOOL
Enable debug messages from libclamav.
Default: no
LeaveTemporaryFiles BOOL
Do not remove temporary files (for debugging purpose).
Default: no
User STRING
Run the daemon as a specified user (the process must be started by root).
Default: disabled
Bytecode BOOL
With this option enabled ClamAV will load bytecode from the database. It is highly recommended you keep
this option turned on, otherwise you may miss detections for many new viruses.
Default: yes
BytecodeSecurity STRING
Set bytecode security level.
Possible values:
TrustSigned - trust bytecode loaded from signed .c[lv]d files and insert runtime safety checks for
bytecode loaded from other sources,
Paranoid - don't trust any bytecode, insert runtime checks for all.
Recommended: TrustSigned, because bytecode in .cvd files already has these checks.
Default: TrustSigned
BytecodeTimeout NUMBER
Set bytecode timeout in milliseconds.
Default: 5000
BytecodeUnsigned BOOL
Allow loading bytecode from outside digitally signed .c[lv]d files.
Default: no
BytecodeMode STRING
Set bytecode execution mode.
Possible values:
Auto - automatically choose JIT if possible, fallback to interpreter
ForceJIT - always choose JIT, fail if not possible
ForceInterpreter - always choose interpreter
Test - run with both JIT and interpreter and compare results. Make all failures fatal.
Default: Auto
DetectPUA BOOL
Detect Possibly Unwanted Applications.
Default: No
ExcludePUA CATEGORY
Exclude a specific PUA category. This directive can be used multiple times. See https://www.cla‐
mav.net/documents/potentially-unwanted-applications-pua for the complete list of PUA categories.
Default: disabled
IncludePUA CATEGORY
Only include a specific PUA category. This directive can be used multiple times. See https://www.cla‐
mav.net/documents/potentially-unwanted-applications-pua for the complete list of PUA categories.
Default: disabled
HeuristicAlerts BOOL
In some cases (eg. complex malware, exploits in graphic files, and others), ClamAV uses special algo‐
rithms to provide accurate detection. This option controls the algorithmic detection.
Default: yes
HeuristicScanPrecedence BOOL
Allow heuristic match to take precedence. When enabled, if a heuristic scan (such as phishingScan) de‐
tects a possible virus/phishing it will stop scanning immediately. Recommended, saves CPU scan-time. When
disabled, virus/phishing detected by heuristic scans will be reported only at the end of a scan. If an
archive contains both a heuristically detected virus/phishing, and a real malware, the real malware will
be reported. Keep this disabled if you intend to handle "*.Heuristics.*" viruses differently from "real"
malware. If a non-heuristically-detected virus (signature-based) is found first, the scan is interrupted
immediately, regardless of this config option.
Default: no
ScanPE BOOL
PE stands for Portable Executable - it's an executable file format used in all 32 and 64-bit versions of
Windows operating systems. This option allows ClamAV to perform a deeper analysis of executable files and
it's also required for decompression of popular executable packers such as UPX.
If you turn off this option, the original files will still be scanned, but without additional processing.
Default: yes
ScanELF BOOL
Executable and Linking Format is a standard format for UN*X executables. This option allows you to con‐
trol the scanning of ELF files.
If you turn off this option, the original files will still be scanned, but without additional processing.
Default: yes
ScanMail BOOL
Enable scanning of mail files.
If you turn off this option, the original files will still be scanned, but without parsing individual
messages/attachments.
Default: yes
ScanPartialMessages BOOL
Scan RFC1341 messages split over many emails. You will need to periodically clean up $TemporaryDirec‐
tory/clamav-partial directory. WARNING: This option may open your system to a DoS attack. Never use it on
loaded servers.
Default: no
PhishingSignatures BOOL
Enable email signature-based phishing detection.
Default: yes
PhishingScanURLs BOOL
Enable URL signature-based phishing detection (Phishing.Heuristics.Email.*)
Default: yes
StructuredDataDetection BOOL
Enable the DLP module.
Default: no
StructuredMinCreditCardCount NUMBER
This option sets the lowest number of Credit Card numbers found in a file to generate a detect.
Default: 3
StructuredMinSSNCount NUMBER
This option sets the lowest number of Social Security Numbers found in a file to generate a detect.
Default: 3
StructuredSSNFormatNormal BOOL
With this option enabled the DLP module will search for valid SSNs formatted as xxx-yy-zzzz.
Default: Yes
StructuredSSNFormatStripped BOOL
With this option enabled the DLP module will search for valid SSNs formatted as xxxyyzzzz.
Default: No
ScanHTML BOOL
Perform HTML/JavaScript/ScriptEncoder normalisation and decryption.
If you turn off this option, the original files will still be scanned, but without additional processing.
Default: yes
ScanOLE2 BOOL
This option enables scanning of OLE2 files, such as Microsoft Office documents and .msi files.
If you turn off this option, the original files will still be scanned, but without additional processing.
Default: yes
ScanPDF BOOL
This option enables scanning within PDF files.
If you turn off this option, the original files will still be scanned, but without additional processing.
Default: yes
ScanSWF BOOL
This option enables scanning within SWF files.
If you turn off this option, the original files will still be scanned, but without decoding and addi‐
tional processing.
Default: yes
ScanXMLDOCS BOOL
This option enables scanning xml-based document files supported by libclamav.
If you turn off this option, the original files will still be scanned, but without additional processing.
Default: yes
ScanHWP3 BOOL
This option enables scanning HWP3 files.
If you turn off this option, the original files will still be scanned, but without additional processing.
Default: yes
ScanArchive BOOL
Scan within archives and compressed files.
If you turn off this option, the original files will still be scanned, but without unpacking and addi‐
tional processing.
Default: yes
AlertBrokenExecutables BOOL
Alert on broken executable files (PE & ELF).
Default: no
AlertEncrypted BOOL
Alert on encrypted archives and documents (encrypted .zip, .7zip, .rar, .pdf).
Default: no
AlertEncryptedArchive BOOL
Alert on encrypted archives (encrypted .zip, .7zip, .rar).
Default: no
AlertEncryptedDoc BOOL
Alert on encrypted documents (encrypted .pdf).
Default: no
AlertOLE2Macros BOOL
Alert on OLE2 files containing VBA macros (Heuristics.OLE2.ContainsMacros).
Default: no
AlertExceedsMax BOOL
Alert on files that exceed max file size, max scan size, or max recursion limit (Heuristics.Limits.Ex‐
ceeded).
Default: no
AlertPhishingSSLMismatch BOOL
Alert on emails containing SSL mismatches in URLs (might lead to false positives!).
Default: no
AlertPhishingCloak BOOL
Alert on emails containing cloaked URLs (might lead to some false positives).
Default: no
AlertPartitionIntersection BOOL
Alert on raw DMG image files containing partition intersections.
Default: no
ForceToDisk
This option causes memory or nested map scans to dump the content to disk.
If you turn on this option, more data is written to disk and is available when the leave-temps option is
enabled at the cost of more disk writes.
Default: no
MaxScanSize SIZE
Sets the maximum amount of data to be scanned for each input file. Archives and other containers are re‐
cursively extracted and scanned up to this value. The size of an archive plus the sum of the sizes of all
files within archive count toward the scan size. For example, a 1M uncompressed archive containing a sin‐
gle 1M inner file counts as 2M toward the max scan size. Warning: disabling this limit or setting it too
high may result in severe damage to the system.
Default: 100M
MaxFileSize SIZE
Files larger than this limit won't be scanned. Affects the input file itself as well as files contained
inside it (when the input file is an archive, a document or some other kind of container). Warning: dis‐
abling this limit or setting it too high may result in severe damage to the system.
Default: 25M
MaxRecursion NUMBER
Nested archives are scanned recursively, e.g. if a Zip archive contains a RAR file, all files within it
will also be scanned. This options specifies how deeply the process should be continued. Warning: setting
this limit too high may result in severe damage to the system.
Default: 16
MaxFiles NUMBER
Number of files to be scanned within an archive, a document, or any other kind of container. Warning:
disabling this limit or setting it too high may result in severe damage to the system.
Default: 10000
MaxEmbeddedPE SIZE
This option sets the maximum size of a file to check for embedded PE.
Files larger than this value will skip the additional analysis step.
Negative values are not allowed.
Default: 10M
MaxHTMLNormalize SIZE
This option sets the maximum size of a HTML file to normalize.
HTML files larger than this value will not be normalized or scanned.
Negative values are not allowed.
Default: 10M
MaxHTMLNoTags SIZE
This option sets the maximum size of a normalized HTML file to scan.
HTML files larger than this value after normalization will not be scanned.
Negative values are not allowed.
Default: 2M
MaxScriptNormalize SIZE
This option sets the maximum size of a script file to normalize.
Script content larger than this value will not be normalized or scanned.
Negative values are not allowed.
Default: 5M
MaxZipTypeRcg SIZE
This option sets the maximum size of a ZIP file to reanalyze type recognition.
ZIP files larger than this value will skip the step to potentially reanalyze as PE.
Negative values are not allowed.
WARNING: setting this limit too high may result in severe damage or impact performance.
Default: 1M
MaxPartitions SIZE
This option sets the maximum number of partitions of a raw disk image to be scanned.
Raw disk images with more partitions than this value will have up to the value partitions scanned.
Negative values are not allowed.
WARNING: setting this limit too high may result in severe damage or impact performance.
Default: 50
MaxIconsPE SIZE
This option sets the maximum number of icons within a PE to be scanned.
PE files with more icons than this value will have up to the value number icons scanned.
Negative values are not allowed.
WARNING: setting this limit too high may result in severe damage or impact performance.
Default: 100
MaxRecHWP3 NUMBER
This option sets the maximum recursive calls to HWP3 parsing function.
HWP3 files using more than this limit will be terminated and alert the user.
Scans will be unable to scan any HWP3 attachments if the recursive limit is reached.
Negative values are not allowed.
WARNING: setting this limit too high may result in severe damage or impact performance.
Default: 16
PCREMatchLimit NUMBER
This option sets the maximum calls to the PCRE match function during an instance of regex matching.
Instances using more than this limit will be terminated and alert the user but the scan will continue.
For more information on match_limit, see the PCRE documentation.
Negative values are not allowed.
WARNING: setting this limit too high may severely impact performance.
Default: 10000
PCRERecMatchLimit NUMBER
This option sets the maximum recursive calls to the PCRE match function during an instance of regex
matching.
Instances using more than this limit will be terminated and alert the user but the scan will continue.
For more information on match_limit_recursion, see the PCRE documentation.
Negative values are not allowed and values > PCREMatchLimit are superfluous.
WARNING: setting this limit too high may severely impact performance.
Default: 2000
PCREMaxFileSize SIZE
This option sets the maximum filesize for which PCRE subsigs will be executed.
Files exceeding this limit will not have PCRE subsigs executed unless a subsig is encompassed to a
smaller buffer.
Negative values are not allowed.
Setting this value to zero disables the limit.
WARNING: setting this limit too high or disabling it may severely impact performance.
Default: 25M
OnAccessIncludePath STRING
This option specifies a directory (including all files and directories inside it), which should be
scanned on access. This option can be used multiple times.
Default: disabled
OnAccessExcludePath STRING
This option allows excluding directories from on-access scanning. It can be used multiple times.
Default: disabled
OnAccessExcludeRootUID BOOL
With this option you can whitelist the root UID (0). Processes run under root will be able to access all
files without triggering scans or permission denied events.
Note that if clamd cannot check the uid of the process that generated an on-access scan event (e.g., be‐
cause OnAccessPrevention was not enabled, and the process already exited), clamd will perform a scan.
Thus, setting OnAccessExcludeRootUID is not guaranteed to prevent every access by the root user from
triggering a scan (unless OnAccessPrevention is enabled).
Default: no
OnAccessExcludeUID NUMBER
With this option you can whitelist specific UIDs. Processes with these UIDs will be able to access all
files without triggering scans or permission denied events.
This option can be used multiple times (one per line).
Note: using a value of 0 on any line will disable this option entirely. To whitelist the root UID (0)
please enable the OnAccessExcludeRootUID option.
Also note that if clamd cannot check the uid of the process that generated an on-access scan event (e.g.,
because OnAccessPrevention was not enabled, and the process already exited), clamd will perform a scan.
Thus, setting OnAccessExcludeUID is not guaranteed to prevent every access by the specified uid from
triggering a scan (unless OnAccessPrevention is enabled).
Default: disabled
OnAccessExcludeUname STRING
This option allows exclusions via user names when using the on-access scanning client. It can be used
multiple times, and has the same potential race condition limitations of the OnAccessExcludeUID option.
Default: disabled
OnAccessMaxFileSize SIZE
Files larger than this value will not be scanned in on access.
Default: 5M
OnAccessMaxThreads NUMBER
Max number of scanning threads to allocate to the OnAccess thread pool at startup. These threads are the
ones responsible for creating a connection with the daemon and kicking off scanning after an event has
been processed. To prevent clamonacc from consuming all clamd's resources keep this lower than clamd's
max threads.
Default: 5
OnAccessCurlTimeout NUMBER
Max amount of time (in milliseconds) that the OnAccess client should spend for every connect, send, and
recieve attempt when communicating with clamd via curl.
Default: 5000 (5 seconds)
OnAccessMountPath STRING
Specifies a mount point (including all files and directories under it), which should be scanned on ac‐
cess. This option can be used multiple times.
Default: disabled
OnAccessDisableDDD BOOL
Disables the dynamic directory determination system which allows for recursively watching include paths.
Default: no
OnAccessPrevention BOOL
Enables fanotify blocking when malicious files are found.
Default: disabled
OnAccessRetryAttempts NUMBER
Number of times the OnAccess client will retry a failed scan due to connection problems (or other is‐
sues).
Default: 0
OnAccessDenyOnError BOOL
When using prevention, if this option is turned on, any errors that occur during scanning will result in
the event attempt being denied. This could potentially lead to unwanted system behaviour with certain
configurations, so the client defaults this to off and prefers allowing access events in case of scan or
connection error.
Default: no
OnAccessExtraScanning BOOL
Toggles extra scanning and notifications when a file or directory is created or moved.
Requires the DDD system to kick-off extra scans.
Default: no
DisableCertCheck BOOL
Disable authenticode certificate chain verification in PE files.
Default: no
NOTES
All options expressing a size are limited to max 4GB. Values in excess will be reset to the maximum.
FILES
/etc/clamav/clamd.conf
AUTHORS
Tomasz Kojm <[email protected]>, Kevin Lin <[email protected]>
SEE ALSO
clamd(8), clamdscan(1), clamav-milter(8), freshclam(1), freshclam.conf(5)
ClamAV 0.102.2 December 4, 2013 clamd.conf(5)