Ubuntu Manpage: ausearch - a tool to query audit daemon logs

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 example, 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 resulting 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 subsequent invocations.

An auditd event is made up of one or more records. When processing 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 subsequent 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 content safer for
certain uses. The options are raw , tty , shell , and shell_quote. Each mode
includes the characters of the preceding 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 triggering 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 formatting options are passed. It includes one line as a visual separator
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) format 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 command
which searches the node field.

-i, --interpret
Interpret numeric entities into text. For example, uid is converted 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 supplemental 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 searching. This is needed
if you are using ausearch from a cron job.

--just-one
Stop after emitting the first event that matches the search criteria.

-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 undesirable. 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
message 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
information 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 event with either scontext/subject or tcontext/object matching the
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 values 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 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, 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, boot, today, yesterday, this-week,
week-ago, this-month, this-year, or checkpoint. 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 midnight on day 0 of the week
determined by your locale (see localtime). 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 daemons 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