You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
suricata/doc/userguide/file-extraction/md5.rst

267 lines
10 KiB
ReStructuredText

This file contains invisible Unicode characters!

This file contains invisible Unicode characters that may be processed differently from what appears below. If your use case is intentional and legitimate, you can safely ignore this warning. Use the Escape button to reveal hidden characters.

.. _md5:
Storing MD5s checksums
======================
In this particular example we are using: Ubuntu 14.04 LTS
Also - we are using the latest git master (git installation)
Make sure you have libnss and libnspr installed
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
::
root@LTS-64-1:~/Work/tmp/oisf# dpkg -l |grep libnss
ii libnss-mdns:amd64 0.10-6 amd64 NSS module for Multicast DNS name resolution
ii libnss3:amd64 2:3.17.4-0ubuntu0.14.04.1 amd64 Network Security Service libraries
ii libnss3-1d:amd64 2:3.17.4-0ubuntu0.14.04.1 amd64 Network Security Service libraries - transitional package
ii libnss3-dev:amd64 2:3.17.4-0ubuntu0.14.04.1 amd64 Development files for the Network Security Service libraries
ii libnss3-nssdb 2:3.17.4-0ubuntu0.14.04.1 all Network Security Security libraries - shared databases
ii libnss3-tools 2:3.17.4-0ubuntu0.14.04.1 amd64 Network Security Service tools
::
root@LTS-64-1:~/Work/tmp/oisf# dpkg -l |grep libnspr
ii libnspr4:amd64 2:4.10.7-0ubuntu0.14.04.1 amd64 NetScape Portable Runtime Library
ii libnspr4-dev 2:4.10.7-0ubuntu0.14.04.1 amd64 Development files for the NetScape Portable Runtime library
If not install them:
::
apt-get install libnss3-dev libnspr4-dev
**Note:** Fedora users need to install the following:
::
nss-util
nss-util-devel
nss-devel
nspr-devel
nspr
Get the Suricata code
~~~~~~~~~~~~~~~~~~~~~
Execute:
::
git clone git://phalanx.openinfosecfoundation.org/oisf.git && cd oisf
git clone https://github.com/OISF/libhtp.git -b 0.5.x
Building Suricata
~~~~~~~~~~~~~~~~~~
You have to compile/install suri like this in order to enable MD5s:
::
./autogen.sh
./configure --with-libnss-libraries=/usr/lib --with-libnss-includes=/usr/include/nss/ --with-libnspr-libraries=/usr/lib --with-libnspr-includes=/usr/include/nspr
make clean
make
sudo make install
Output of configure:
::
Suricata Configuration:
  AF_PACKET support:                       yes
  PF_RING support:                         no
  NFQueue support:                         no
  IPFW support:                            no
  DAG enabled:                             no
  Napatech enabled:                        no
  libnss support:                          yes
  libnspr support:                         yes
  Prelude support:                         no
  PCRE jit:                                no
This is what is important to have:
::
libnss support:                          yes
libnspr support:                         yes
Confirm everything is built correctly:
::
# suricata --build-info
[10010] 1/5/2012 -- 11:16:23 - (suricata.c:502) <Info> (SCPrintBuildInfo) -- This is Suricata version 1.3dev (rev e6dea5c)
[10010] 1/5/2012 -- 11:16:23 - (suricata.c:575) <Info> (SCPrintBuildInfo) -- Features: PCAP_SET_BUFF LIBPCAP_VERSION_MAJOR=1 AF_PACKET HAVE_PACKET_FANOUT LIBCAP_NG LIBNET1.1 HAVE_HTP_URI_NORMALIZE_HOOK HAVE_HTP_TX_GET_RESPONSE_HEADERS_RAW HAVE_NSS
[10010] 1/5/2012 -- 11:16:23 - (suricata.c:589) <Info> (SCPrintBuildInfo) -- 32-bits, Little-endian architecture
[10010] 1/5/2012 -- 11:16:23 - (suricata.c:591) <Info> (SCPrintBuildInfo) -- GCC version 4.4.5, C version 199901
[10010] 1/5/2012 -- 11:16:23 - (suricata.c:597) <Info> (SCPrintBuildInfo) -- __GCC_HAVE_SYNC_COMPARE_AND_SWAP_1
[10010] 1/5/2012 -- 11:16:23 - (suricata.c:600) <Info> (SCPrintBuildInfo) -- __GCC_HAVE_SYNC_COMPARE_AND_SWAP_2
[10010] 1/5/2012 -- 11:16:23 - (suricata.c:603) <Info> (SCPrintBuildInfo) -- __GCC_HAVE_SYNC_COMPARE_AND_SWAP_4
[10010] 1/5/2012 -- 11:16:23 - (suricata.c:606) <Info> (SCPrintBuildInfo) -- __GCC_HAVE_SYNC_COMPARE_AND_SWAP_8
[10010] 1/5/2012 -- 11:16:23 - (suricata.c:613) <Info> (SCPrintBuildInfo) -- compiled with -fstack-protector
[10010] 1/5/2012 -- 11:16:23 - (suricata.c:619) <Info> (SCPrintBuildInfo) -- compiled with _FORTIFY_SOURCE=2
Make sure we have **HAVE_NSS** in the **Features** line.
Configuration
~~~~~~~~~~~~~
In the suricata yaml:
::
 - file-store:
      enabled: yes       # set to yes to enable
      log-dir: files    # directory to store the files
      force-magic: yes   # force logging magic on all stored files
      force-md5: yes     # force logging of md5 checksums
      #waldo: file.waldo # waldo file to store the file_id across runs
Optionally, for JSON output:
::
- file-log:
enabled: yes
filename: files-json.log
append: no
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 Suricta (-S option loads ONLY the specified rule file, with disregard if any other rules that are enabled in suricata.yaml):
::
suricata -c /etc/suricata/suricata.yaml -S file.rules -i eth0
I tried that link (Cisco Prod Brochure PDF, just googled "Cisco PDF"):
* http://www.cisco.com/c/en/us/products/routers/3800-series-integrated-services-routers-isr/index.html
and in file directory (/var/log/suricata/files) I got the 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:
enabled: no # set to yes to enable
log-dir: files # directory to store the files
force-magic: yes # force logging magic on all stored files
force-md5: yes # force logging of md5 checksums
#waldo: file.waldo # waldo file to store the file_id across runs
- file-log:
enabled: yes
filename: files-json.log
append: no
#filetype: regular # 'regular', 'unix_stream' or 'unix_dgram'
force-magic: yes # force logging magic on all logged files
force-md5: yes # force logging of md5 checksums
This is in short what is needed to have MD5s logged.