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.. _md5:
Storing MD5s checksums
======================
Configuration
~~~~~~~~~~~~~
In the Suricata config file:
::
- file-store:
enabled: yes # set to yes to enable
dir: filestore # directory to store the files
force-hash: [md5] # force logging of md5 checksums
For JSON output:
::
outputs:
- eve-log:
enabled: yes
filetype: regular #regular|syslog|unix_dgram|unix_stream|redis
filename: eve.json
types:
- files:
force-magic: no # force logging magic on all logged files
# force logging of checksums, available hash functions are md5,
# sha1 and sha256
#force-hash: [md5]
Other settings affecting :doc:`file-extraction`
::
stream:
memcap: 64mb
checksum-validation: yes # reject wrong csums
inline: no # no inline mode
reassembly:
memcap: 32mb
depth: 0 # reassemble all of a stream
toserver-chunk-size: 2560
toclient-chunk-size: 2560
Make sure we have *depth: 0* so all files can be tracked fully.
::
libhtp:
default-config:
personality: IDS
# Can be specified in kb, mb, gb. Just a number indicates
# it's in bytes.
request-body-limit: 0
response-body-limit: 0
Make sure we have *request-body-limit: 0* and *response-body-limit: 0*
Testing
~~~~~~~
For the purpose of testing we use this rule only in a file.rules (a test/example file):
::
alert http any any -> any any (msg:"FILE store all"; filestore; sid:1; rev:1;)
This rule above will save all the file data for files that are opened/downloaded through HTTP
Start Suricata (``-S`` option *ONLY loads* the specified rule file and disregards any other rules that are enabled in suricata.yaml):
::
suricata -c /etc/suricata/suricata.yaml -S file.rules -i eth0
Meta data:
::
TIME: 05/01/2012-11:09:52.425751
SRC IP: 2.23.144.170
DST IP: 192.168.1.91
PROTO: 6
SRC PORT: 80
DST PORT: 51598
HTTP URI: /en/US/prod/collateral/routers/ps5855/prod_brochure0900aecd8019dc1f.pdf
HTTP HOST: www.cisco.com
HTTP REFERER: http://www.cisco.com/c/en/us/products/routers/3800-series-integrated-services-routers-isr/index.html
FILENAME: /en/US/prod/collateral/routers/ps5855/prod_brochure0900aecd8019dc1f.pdf
MAGIC: PDF document, version 1.6
STATE: CLOSED
MD5: 59eba188e52467adc11bf2442ee5bf57
SIZE: 9485123
and in files-json.log (or eve.json) :
::
{ "id": 1, "timestamp": "05\/01\/2012-11:10:27.693583", "ipver": 4, "srcip": "2.23.144.170", "dstip": "192.168.1.91", "protocol": 6, "sp": 80, "dp": 51598, "http_uri": "\/en\/US\/prod\/collateral\/routers\/ps5855\/prod_brochure0900aecd8019dc1f.pdf", "http_host": "www.cisco.com", "http_referer": "http:\/\/www.google.com\/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0CDAQFjAA&url=http%3A%2F%2Fwww.cisco.com%2Fen%2FUS%2Fprod%2Fcollateral%2Frouters%2Fps5855%2Fprod_brochure0900aecd8019dc1f.pdf&ei=OqyfT9eoJubi4QTyiamhAw&usg=AFQjCNGdjDBpBDfQv2r3VogSH41V6T5x9Q", "filename": "\/en\/US\/prod\/collateral\/routers\/ps5855\/prod_brochure0900aecd8019dc1f.pdf", "magic": "PDF document, version 1.6", "state": "CLOSED", "md5": "59eba188e52467adc11bf2442ee5bf57", "stored": true, "size": 9485123 }
{ "id": 12, "timestamp": "05\/01\/2012-11:12:57.421420", "ipver": 4, "srcip": "2.23.144.170", "dstip": "192.168.1.91", "protocol": 6, "sp": 80, "dp": 51598, "http_uri": "\/en\/US\/prod\/collateral\/routers\/ps5855\/prod_brochure0900aecd8019dc1f.pdf", "http_host": "www.cisco.com", "http_referer": "http:\/\/www.google.com\/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0CDAQFjAA&url=http%3A%2F%2Fwww.cisco.com%2Fen%2FUS%2Fprod%2Fcollateral%2Frouters%2Fps5855%2Fprod_brochure0900aecd8019dc1f.pdf&ei=OqyfT9eoJubi4QTyiamhAw&usg=AFQjCNGdjDBpBDfQv2r3VogSH41V6T5x9Q", "filename": "\/en\/US\/prod\/collateral\/routers\/ps5855\/prod_brochure0900aecd8019dc1f.pdf", "magic": "PDF document, version 1.6", "state": "CLOSED", "md5": "59eba188e52467adc11bf2442ee5bf57", "stored": true, "size": 9485123 }
Log all MD5s without any rules
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
If you would like to log MD5s for everything and anything that passes through the traffic that you are inspecting with Suricata, but not log the files themselves, all you have to do is disable file-store and enable only the JSON output with forced MD5s - in suricata.yaml like so:
::
- file-store:
version: 2
enabled: no # set to yes to enable
log-dir: files # directory to store the files
force-filestore: no
force-hash: [md5] # force logging of md5 checksums
|
