zeek/scripts/policy/protocols/conn/known-hosts.bro
Jon Siwek 47500ceef4 Add a test that checks each individual script can be loaded in bare-mode.
Fixed most @load dependency issues in the process.  The test is still
failing in a "known" way due to hot.conn.bro and scan.bro.

Adressess #545
2011-08-10 15:38:21 -05:00

52 lines
1.5 KiB
Text

##! This script logs hosts that Bro determines have performed complete TCP
##! handshakes and logs the address once per day (by default). The log that
##! output provides an easy way to determine a count of the IP addresses in
##! use on a network per day.
@load base/utils/directions-and-hosts
module KnownHosts;
export {
redef enum Log::ID += { KNOWN_HOSTS };
type Info: record {
## The timestamp at which the host was detected.
ts: time &log;
## The address that was detected originating or responding to a TCP
## connection.
host: addr &log;
};
## The hosts whose existence should be logged and tracked.
## Choices are: LOCAL_HOSTS, REMOTE_HOSTS, ALL_HOSTS, NO_HOSTS
const asset_tracking = LOCAL_HOSTS &redef;
## The set of all known addresses to store for preventing duplicate
## logging of addresses. It can also be used from other scripts to
## inspect if an address has been seen in use.
## Maintain the list of known hosts for 24 hours so that the existence
## of each individual address is logged each day.
global known_hosts: set[addr] &create_expire=1day &synchronized &redef;
global log_known_hosts: event(rec: Info);
}
event bro_init()
{
Log::create_stream(KNOWN_HOSTS, [$columns=Info, $ev=log_known_hosts]);
}
event connection_established(c: connection) &priority=5
{
local id = c$id;
for ( host in set(id$orig_h, id$resp_h) )
{
if ( host !in known_hosts && addr_matches_host(host, asset_tracking) )
{
add known_hosts[host];
Log::write(KNOWN_HOSTS, [$ts=network_time(), $host=host]);
}
}
}