AUSEARCH(8) System Administration Utilities AUSEARCH(8)
NAME
ausearch - a tool to query audit daemon logs
SYNOPSIS
ausearch [options]
DESCRIPTION
ausearch is a tool that can query the audit daemon logs based for
events based on different search criteria. The ausearch utility can
also take input from stdin as long as the input is the raw log data.
Each commandline option given forms an "and" statement. For example,
searching with -m and -ui means return events that have both the
requested type and match the user id given. An exception is the -m and
-n options; multiple record types and nodes are allowed in a search
which will return any matching node and record.
It should also be noted that each syscall excursion from user space
into the kernel and back into user space has one event ID that is
unique. Any auditable event that is triggered during this trip share
this ID so that they may be correlated.
Different parts of the kernel may add supplemental records. For exam-
ple, an audit event on the syscall "open" will also cause the kernel to
emit a PATH record with the file name. The ausearch utility will
present all records that make up one event together. This could mean
that even though you search for a specific kind of record, the result-
ing events may contain SYSCALL records.
Also be aware that not all record types have the requested information.
For example, a PATH record does not have a hostname or a loginuid.
OPTIONS
-a, --event audit-event-id
Search for an event based on the given event ID. Messages always
start with something like msg=audit(1116360555.329:2401771). The
event ID is the number after the ':'. All audit events that are
recorded from one application's syscall have the same audit
event ID. A second syscall made by the same application will
have a different event ID. This way they are unique.
--arch CPU
Search for events based on a specific CPU architecture. If you
do not know the arch of your machine but you want to use the 32
bit syscall table and your machine supports 32 bits, you can
also use b32 for the arch. The same applies to the 64 bit
syscall table, you can use b64. The arch of your machine can be
found by doing 'uname -m'.
-c, --comm comm-name
Search for an event based on the given comm name. The comm name
is the executable's name from the task structure.
--debug
Write malformed events that are skipped to stderr.
--checkpoint checkpoint-file
Checkpoint the output between successive invocations of ausearch
such that only events not previously output will print in subse-
quent invocations.
An auditd event is made up of one or more records. When process-
ing events, ausearch defines events as either complete or in-
complete. A complete event is either a single record event or
one whose event time occurred 2 seconds in the past compared to
the event being currently processed.
A checkpoint is achieved by recording the last completed event
output along with the device number and inode of the file the
last completed event appeared in checkpoint-file. On a subse-
quent invocation, ausearch will load this checkpoint data and as
it processes the log files, it will discard all complete events
until it matches the checkpointed one. At this point, it will
start outputting complete events.
Should the file or the last checkpointed event not be found, one
of a number of errors will result and ausearch will terminate.
See EXIT STATUS for detail.
--eoe-timeout seconds
Set the end of event parsing timeout. See end_of_event_timeout
in auditd.conf(5) for details. Note that setting this value will
override any configured value found in /etc/auditd/auditd.conf.
-e, --exit exit-code-or-errno
Search for an event based on the given syscall exit code or
errno.
--escape option
This option determines if the output is escaped to make the con-
tent safer for certain uses. The options are raw , tty , shell ,
and shell_quote. Each mode includes the characters of the pre-
ceding mode and escapes more characters. That is to say shell
includes all characters escaped by tty and adds more. tty is the
default.
--extra-keys
When the format mode is csv, this option will add a final column
with key information if its exists for the event. This would
only occur on SYSCALL records which were the result of trigger-
ing an audit rule that defines a key.
--extra-labels
When the format mode is csv, this option will add columns of
information about subject and object labels when they exist.
--extra-obj2
When the format mode is csv, this option will add columns of
information about a second object when it exists. It's rare that
a second object is part of a record. Some examples are when a
file is renamed from one name to another or when a device is
mounted to a path.
--extra-time
When the format mode is csv, this option will add columns of
information about broken down time to make subsetting easier.
-f, --file file-name
Search for an event based on the given filename. The argument
will match normal files as well as af_unix sockets.
--format option
Events that match the search criteria are formatted using this
option. The supported formats are: raw, default, interpret, csv,
and text. The raw option is described under the --raw command
line option. The default option is what you get when no format-
ting options are passed. It includes one line as a visual sepa-
rator which indicates the time stamp and then the records of the
event follow. The interpret option is explained under the -i
command line option. The csv option outputs the results of the
search as a normalized event in comma separated value (CSV) for-
mat suitable for import into analytical programs. The text
option turns the event into an English sentence that is easier
to understand than other options, but it comes at the expense of
loss of detail. In most cases this is perfectly fine since the
original event still retains all the original information.
-ga, --gid-all all-group-id
Search for an event with either effective group ID or group ID
matching the given group ID.
-ge, --gid-effective effective-group-id
Search for an event with the given effective group ID or group
name.
-gi, --gid group-id
Search for an event with the given group ID or group name.
-h, --help
Help
-hn, --host host-name
Search for an event with the given host name. The hostname can
be either a hostname, fully qualified domain name, or numeric
network address. No attempt is made to resolve numeric addresses
to domain names or aliases. This search typically correlates to
the addr or host field of audit events. Also see the --node com-
mand which searches the node field.
-i, --interpret
Interpret numeric entities into text. For example, uid is con-
verted to account name. If the audit logs are unenriched, the
conversion is done using the current resources of the machine
where the search is being run. If you have renamed the accounts,
or don't have the same accounts on your machine, you could get
misleading results. If the logs are enriched, it uses the sup-
plemental data to do the conversion. This allows accurate log
reporting even when run on a different machine than the original
logs came from.
-if, --input file-name | directory
Use the given file or directory instead of the logs. This is to
aid analysis where the logs have been moved to another machine
or only part of a log was saved. The path length is limited to
4064 bytes.
--input-logs
Use the log file location from auditd.conf as input for search-
ing. This is needed if you are using ausearch from a cron job.
--just-one
Stop after emitting the first event that matches the search cri-
teria.
-k, --key key-string
Search for an event based on the given key string.
-l, --line-buffered
Flush output on every line. Most useful when stdout is connected
to a pipe and the default block buffering strategy is undesir-
able. May impose a performance penalty.
-m, --message message-type | comma-sep-message-type-list
Search for an event matching the given message type. (Message
types are also known as record types.) You may also enter a
comma separated list of message types or multiple individual
message types each with its own -m option. There is an ALL mes-
sage type that doesn't exist in the actual logs. It allows you
to get all messages in the system. The list of valid messages
types is long. The program will display the list whenever no
message type is passed with this parameter. The message type can
be either text or numeric. If you enter a list, there can be
only commas and no spaces separating the list.
-n, --node
Search for events originating from a specific machine. Multiple
nodes are allowed, and if any nodes match, the event is matched.
This search uses the node field in audit events. Also see the
--host command which search for events related to host informa-
tion in the audit trail.
-o, --object SE-Linux-context-string
Search for event with tcontext (object) matching the string.
-p, --pid process-id
Search for an event matching the given process ID.
-pp, --ppid parent-process-id
Search for an event matching the given parent process ID.
-r, --raw
Output is completely unformatted. This is useful for extracting
records to a file that can still be interpreted by audit tools
or when piping to other audit tools.
-sc, --syscall syscall-name-or-value
Search for an event matching the given syscall. You may either
give the numeric syscall value or the syscall name. If you give
the syscall name, it will use the syscall table for the machine
that you are using.
-se, --context SE-Linux-context-string
Search for events with either scontext/subject or tcon-
text/object matching the given string.
--session Login-Session-ID
Search for events matching the given Login Session ID. This
process attribute is set when a user logs in and can tie any
process to a particular user login.
-su, --subject SE-Linux-context-string
Search for event with scontext (subject) matching the string.
-sv, --success success-value
Search for an event matching the given success value. Legal val-
ues are yes and no.
-te, --end [end-date] [end-time]
Search for events with time stamps equal to or before the given
end time. The format of end time depends on your locale. You can
check the format of your locale by running date '+%x'. If the
date is omitted, today is assumed. If the time is omitted, now
is assumed. Use 24 hour clock time rather than AM or PM to spec-
ify time. An example date using the en_US.utf8 locale is
09/03/2009. An example of time is 18:00:00. The date format
accepted is influenced by the LC_TIME environmental variable.
You may also use the word: now, recent, this-hour, boot, today,
yesterday, this-week, week-ago, this-month, or this-year. Now
means starting now. Recent is 10 minutes ago. Boot means the
time of day to the second when the system last booted. Today
means now. Yesterday is 1 second after midnight the previous
day. This-week means starting 1 second after midnight on day 0
of the week determined by your locale (see localtime). Week-ago
means 1 second after midnight exactly 7 days ago. This-month
means 1 second after midnight on day 1 of the month. This-year
means the 1 second after midnight on the first day of the first
month.
-ts, --start [start-date] [start-time]
Search for events with time stamps equal to or after the given
start time. The format of start time depends on your locale. You
can check the format of your locale by running date '+%x'. If
the date is omitted, today is assumed. If the time is omitted,
midnight is assumed. Use 24 hour clock time rather than AM or PM
to specify time. An example date using the en_US.utf8 locale is
09/03/2009. An example of time is 18:00:00. The date format
accepted is influenced by the LC_TIME environmental variable.
You may also use the word: now, recent, this-hour, boot, today,
yesterday, this-week, week-ago, this-month, this-year, or check-
point. Boot means the time of day to the second when the system
last booted. Today means starting at 1 second after midnight.
Recent is 10 minutes ago. Yesterday is 1 second after midnight
the previous day. This-week means starting 1 second after mid-
night on day 0 of the week determined by your locale (see local-
time). Week-ago means starting 1 second after midnight exactly 7
days ago. This-month means 1 second after midnight on day 1 of
the month. This-year means the 1 second after midnight on the
first day of the first month.
checkpoint means ausearch will use the timestamp found within a
valid checkpoint file ignoring the recorded inode, device,
serial, node and event type also found within a checkpoint file.
Essentially, this is the recovery action should an invocation of
ausearch with a checkpoint option fail with an exit status of
10, 11 or 12. It could be used in a shell script something like:
ausearch --checkpoint /etc/audit/auditd_checkpoint.txt -i
_au_status=$?
if test ${_au_status} eq 10 -o ${_au_status} eq 11 -o ${_au_status} eq 12
then
ausearch --checkpoint /etc/audit/auditd_checkpoint.txt --start checkpoint -i
fi
-tm, --terminal terminal
Search for an event matching the given terminal value. Some dae-
mons such as cron and atd use the daemon name for the terminal.
-ua, --uid-all all-user-id
Search for an event with either user ID, effective user ID, or
login user ID (auid) matching the given user ID.
-ue, --uid-effective effective-user-id
Search for an event with the given effective user ID.
-ui, --uid user-id
Search for an event with the given user ID.
-ul, --loginuid login-id
Search for an event with the given login user ID. All entry
point programs that are PAMified need to be configured with
pam_loginuid required for the session for searching on loginuid
(auid) to be accurate.
-uu, --uuid guest-uuid
Search for an event with the given guest UUID.
-v, --version
Print the version and exit
-vm, --vm-name guest-name
Search for an event with the given guest name.
-w, --word
String based matches must match the whole word. This category of
matches include: filename, hostname, terminal, keys, and SE
Linux context.
-x, --executable executable
Search for an event matching the given executable name.
EXIT STATUS
0 if OK,
1 if nothing found, or argument errors or minor file access/read
errors,
10 invalid checkpoint data found in checkpoint file,
11 checkpoint processing error
12 checkpoint event not found in matching log file
NOTE
The boot time option is a convenience function and has limitations. The
time it calculates is based on time now minus /proc/uptime. If after
boot the system clock has been adjusted, perhaps by ntp, then the cal-
culation may be wrong. In that case you'll need to fully specify the
time. You can check the time it would use by running:
date -d "`cut -f1 -d. /proc/uptime` seconds ago"
EXAMPLES
Search for a specific user:
# ausearch --start today --loginuid john -i
Check the SELinux log for any denials today
# ausearch --start today -m avc -i
Output logs in text format
# ausearch --start today --format text
Output TTY events interpreted and shell escaped
# ausearch --start today -m TTY -i --escape shell_quote
SEE ALSO
auditd(8), auditd.conf(5), aureport(8), pam_loginuid(8).
Red Hat July 2023 AUSEARCH(8)
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