Fix race condition in unified2 file analyzer startup.

Retrieval of extended alert information from sid-msg.map, gen-msg.map,
and classification.config files uses Bro's input framework, but since
the unified2 file analyzer also relies on the input framework,
coordination is needed to start analysis only after extended info has
been read at least once.
This commit is contained in:
Jon Siwek 2015-01-05 15:21:13 -06:00
parent 494545f1eb
commit 1971d25a5c
4 changed files with 94 additions and 31 deletions

View file

@ -71,11 +71,50 @@ global classification_map: table[count] of string;
global sid_map: table[count] of string;
global gen_map: table[count] of string;
global num_classification_map_reads = 0;
global num_sid_map_reads = 0;
global num_gen_map_reads = 0;
global watching = F;
# For reading in config files.
type OneLine: record {
line: string;
};
function mappings_initialized(): bool
{
return num_classification_map_reads > 0 &&
num_sid_map_reads > 0 &&
num_gen_map_reads > 0;
}
function start_watching()
{
if ( watching )
return;
watching = T;
if ( watch_dir != "" )
{
Dir::monitor(watch_dir, function(fname: string)
{
Input::add_analysis([$source=fname,
$reader=Input::READER_BINARY,
$mode=Input::STREAM,
$name=fname]);
}, 10secs);
}
if ( watch_file != "" )
{
Input::add_analysis([$source=watch_file,
$reader=Input::READER_BINARY,
$mode=Input::STREAM,
$name=watch_file]);
}
}
function create_info(ev: IDSEvent): Info
{
local info = Info($ts=ev$ts,
@ -136,11 +175,33 @@ event Unified2::read_classification_line(desc: Input::EventDescription, tpe: Inp
}
}
event Input::end_of_data(name: string, source: string)
{
if ( name == classification_config )
++num_classification_map_reads;
else if ( name == sid_msg )
++num_sid_map_reads;
else if ( name == gen_msg )
++num_gen_map_reads;
else
return;
if ( watching )
return;
if ( mappings_initialized() )
start_watching();
}
event bro_init() &priority=5
{
Log::create_stream(Unified2::LOG, [$columns=Info, $ev=log_unified2]);
if ( sid_msg != "" )
if ( sid_msg == "" )
{
num_sid_map_reads = 1;
}
else
{
Input::add_event([$source=sid_msg,
$reader=Input::READER_RAW,
@ -151,7 +212,11 @@ event bro_init() &priority=5
$ev=Unified2::read_sid_msg_line]);
}
if ( gen_msg != "" )
if ( gen_msg == "" )
{
num_gen_map_reads = 1;
}
else
{
Input::add_event([$source=gen_msg,
$name=gen_msg,
@ -162,7 +227,11 @@ event bro_init() &priority=5
$ev=Unified2::read_gen_msg_line]);
}
if ( classification_config != "" )
if ( classification_config == "" )
{
num_classification_map_reads = 1;
}
else
{
Input::add_event([$source=classification_config,
$name=classification_config,
@ -173,24 +242,8 @@ event bro_init() &priority=5
$ev=Unified2::read_classification_line]);
}
if ( watch_dir != "" )
{
Dir::monitor(watch_dir, function(fname: string)
{
Input::add_analysis([$source=fname,
$reader=Input::READER_BINARY,
$mode=Input::STREAM,
$name=fname]);
}, 10secs);
}
if ( watch_file != "" )
{
Input::add_analysis([$source=watch_file,
$reader=Input::READER_BINARY,
$mode=Input::STREAM,
$name=watch_file]);
}
if ( mappings_initialized() )
start_watching();
}
event file_new(f: fa_file)