[syslog-ng] Cisco ASA parsing with patterndb/elasticsearch
Evan Rempel
erempel at uvic.ca
Wed Feb 28 02:05:35 UTC 2018
The program name will have an implied @ANYSTRING@ on the end, so if the
syslog payload could
be parsed to detect the program name of %ASA..... then your
patterndb.xml would work.
The problem is that they syslog payload can not be parsed.
What we do is use a hand crafted patterndb to detect all of the
different problem formats
that Cisco logs (in our environment) and change
a) the PROGRAM to be cisco_ASA or generally cisco_XXX where the XXX is
the leading characters of the %XXX-#-##### of the syslog body.
b) the MESSAGE to be %XXX-#-####... for the rest of the line.
All of the poor hosts, sequence numbers, timestamps etc are all thrown away.
After that, the internal buffers of syslog-ng contain a usable PROGRAM
and MESSAGE such that we can use
a patterndb to match the message part of the log line.
This does mean that we have two patterndb parsers for every log line but
it seems to work well for us.
What would work better is if Cisco would fix their logging, but that
isn't going to happen in my lifetime :-(
I hope that makes sense.
Evan.
On 02/27/2018 05:37 PM, Tim Ghetti wrote:
>
> Ok, that makes sense. I sort of suspected that this was due to the
> program name not matching, since pdbtool works when specifying the
> program name. Do you know if there is a way to configure patterndb so
> that it matches the program name, regardless of the full program name
> with event code? Is it possible to regex the program or use the
> patterndb format i.e. <pattern>%ASA at ANYSTRING::@</pattern> or
> something similar?
>
> Tim
>
> *From:*syslog-ng [mailto:syslog-ng-bounces at lists.balabit.hu] *On
> Behalf Of *Evan Rempel
> *Sent:* Tuesday, February 27, 2018 8:26 PM
> *To:* syslog-ng at lists.balabit.hu
> *Subject:* Re: [syslog-ng] Cisco ASA parsing with patterndb/elasticsearch
>
> Welcome to the horrible world of Cisco logging :-(
>
> The issue you are bumping into is that when these log lines are parsed
> by syslog-ng (or any
> syslog daemon that does not specifically understand Cisco logs) there
> is no program name, or the
> program name is the full %ASA-4-106023 part of the log line. There are
> so many ways that Cisco
> can log incorrectly it is not possible to say without seeing your
> exact log lines.
>
> Cisco can add a * to the date/time stamp to indicate that there is no
> time server configured on the device.
> That makes the date/time invalid as far as parsing is concerned.
>
> Cisco can add a period (.) to the date/time stamp to indicate that
> there is a time server configured on
> the device, but the time server can not be reached. Again, this makes
> the date/time invalid as far as parsing
> is concerned.
>
> Cisco can add a sequence number at the start of the log line rather
> than starting the line with a date/6time stamp.
> Invalid parsing again.
>
> Cisco can leave out the sequence number but still include the trailing
> colon from the sequence number.
>
> You get the idea. So many ways to get it wrong, and they never get it
> right :-(
>
> Evan.
>
> On 02/27/2018 04:46 PM, Tim Ghetti wrote:
>
> Hi – having some trouble getting paterndb functional and looking
> for some help. I would like to use patterndb to parse my cisco ass
> firewall logs before sending it to elasticsearch. However when the
> messages get to elasticsearch, I don’t see the messages being
> parsed. Running pdbtool against the logs seems to work.
>
> # pdbtool match -p /etc/syslog-ng/patterndb.d/ciscoasa.pdb -P %ASA
> -f /var/log/asatest.log |more
>
> HOST=X.X.X.X
>
> MESSAGE=Built dynamic TCP translation from INSIDE:X.X.X.X/X to
> OUTSIDE:X.X.X.X/X
>
> PROGRAM=%ASA-6-305011
>
> LEGACY_MSGHDR=%ASA-6-305011:
>
> .classifier.class=system
>
> .classifier.rule_id=e075efdc-c25f-5e49-a208-7661e3b5a29b
>
> Protocol=TCP
>
> GlobalIP=X.X.X.X
>
> GlobalPort=X
>
> LocalIP=X.X.X.X
>
> LocalPort=X
>
> TAGS=.classifier.system
>
> **********************
>
> SYSLOG-NG CONF FILE
>
> @version: 3.11
>
> source s_network { tcp(); udp(); };
>
> destination d_elastic {
>
> elasticsearch2(
>
> client-mode("http")
>
> cluster("ITESCL001")
>
> index("logstash-syslogng_${YEAR}.${MONTH}.${DAY}")
>
> cluster-url("http://X.X.X.X:9200")
>
> type("syslog")
>
> flush-limit("1")
>
> );
>
> };
>
> destination d_catchall { file("/var/log/catchall.log"); };
>
> filter f_ciscoasa { host("X.X.X.X"); };
>
> parser p_ciscoasa
> {db-parser(file("/etc/syslog-ng/patterndb.d/ciscoasa.pdb"));};
>
> log { source(s_network); filter(f_ciscoasa); parser(p_ciscoasa);
> destination(d_elastic); flags(final, flow-control); };
>
> log { source(s_network); destination(d_catchall); };
>
> **********************
>
> PATTERNDB FILE
>
> <?xml version='1.0' encoding='UTF-8'?>
>
> <patterndb version='4' pub_date='2018-02-19'>
>
> <ruleset name='%ASA' id='a300d776-8bd7-834d-a4a9-23eb81a4b3ba'>
>
> <pattern>%ASA</pattern>
>
> <description>
>
> This ruleset covers the Cisco ASA firewalls
>
> </description>
>
> <rules>
>
> <rule provider="%ASA"
> id="b3de7699-8213-c744-944e-9413298afe86" class="system">
>
> <!-- support: 1594 -->
>
> <patterns>
>
> <pattern>Teardown @ESTRING:Protocol: @connection for
> faddr @IPv4:SrcIP:/@@ESTRING:SrcPort: @gaddr
> @IPv4:GlobalIP:/@@ESTRING:GlobalPort: @laddr
> @IPv4:LocalIP:/@@ESTRING:LocalPort:@</pattern>
>
> </patterns>
>
> <examples>
>
> <example>
>
> <test_message program='%ASA'>Teardown ICMP
> connection for faddr X.X.X.X/X gaddr X.X.X.X/X laddr
> X.X.X.X/X</test_message>
>
> </example>
>
> </examples>
>
> </rule>
>
> <rule id='90d0f8c9-7591-d44e-b886-2f7e5cb17ce6'
> class='system' provider='%ASA'>
>
> <!-- support: 1369 -->
>
> <patterns>
>
> <pattern>Teardown dynamic @ESTRING:Protocol:
> @translation from @ESTRING:::@@IPv4:LocalIP:/@@ESTRING:LocalPort:
> @to @ESTRING:::@@IPv4:GlobalIP:/@@ESTRING:GlobalPort:
> @duration at ANYSTRING::@</pattern>
>
> </patterns>
>
> <examples>
>
> <example>
>
> <test_message program='%ASA'>Teardown dynamic UDP
> translation from any:X.X.X.X/X to outside:X.X.X.X/X duration
> 0:00:00</test_message>
>
> </example>
>
> </examples>
>
> </rule>
>
> <rule id='8f0a8d57-80c6-4745-8a8a-5ce018bb0d87'
> class='system' provider='%ASA'>
>
> <!-- support: 1254 -->
>
> <patterns>
>
> <pattern>Teardown @ESTRING:Protocol: @connection
> @ESTRING:: @for @ESTRING:::@@IPv4:DstIP:/@@ESTRING:DstPort: @to
> @ESTRING:::@@IPv4:SrcIP:/@@ESTRING:SrcPort: @@ESTRING::@</pattern>
>
> </patterns>
>
> <examples>
>
> <example>
>
> <test_message program='%ASA'>Teardown UDP
> connection 55101037 for outside:X.X.X.X/X to inside:X.X.X.X/X
> duration 0:00:00 bytes 132</test_message>
>
> </example>
>
> </examples>
>
> </rule>
>
> <rule id='00c0732d-1e34-7340-a75f-21198bf71137'
> class='system' provider='%ASA'>
>
> <!-- support: 1256 -->
>
> <patterns>
>
> <pattern>Built outbound @ESTRING:Protocol: @connection
> @ESTRING:: @for @ESTRING:::@@IPv4:DstIP:/@@ESTRING:DstPort:
> @(@ESTRING::)@ to @ESTRING:::@@IPv4:SrcIP:/@@ESTRING:SrcPort:
> @(@ESTRING::)@</pattern>
>
> </patterns>
>
> <examples>
>
> <example>
>
> <test_message program='%ASA'>Built outbound UDP
> connection 55101037 for outside:X.X.X.X/X (X.X.X.X/X) to
> inside:X.X.X.X/X (X.X.X.X/X)</test_message>
>
> </example>
>
> </examples>
>
> </rule>
>
> <rule id='4a586711-ebe2-dc4d-bf6e-e512666d8c5d'
> class='system' provider='%ASA'>
>
> <!-- support: 1594 -->
>
> <patterns>
>
> <pattern>Built inbound @ESTRING:Protocol: @connection
> for faddr @IPv4:SrcIP:/@@ESTRING:SrcPort: @gaddr
> @IPv4:GlobalIP:/@@ESTRING:GlobalPort: @laddr
> @IPv4:LocalIP:/@@ESTRING:LocalPort:@</pattern>
>
> </patterns>
>
> <examples>
>
> <example>
>
> <test_message program='%ASA'>Built inbound ICMP
> connection for faddr X.X.X.X/X gaddr X.X.X.X/X laddr
> X.X.X.X/X</test_message>
>
> </example>
>
> </examples>
>
> </rule>
>
> <rule id='8be7928d-66e7-7042-abd5-869d6b49c56e'
> class='system' provider='%ASA'>
>
> <!-- support: 1763 -->
>
> <patterns>
>
> <pattern>Built inbound @ESTRING:Protocol: @connection
> @ESTRING:: @for @ESTRING::@@IPv4:SrcIP:/@@ESTRING:SrcPort:
> @(@ESTRING::)@ to identity:@IPv4:DstIP:/@@ESTRING:DstPort:
> @(@ESTRING::)@</pattern>
>
> </patterns>
>
> <examples>
>
> <example>
>
> <test_message program='%ASA'>Built inbound UDP
> connection 55101078 for inside:X.X.X.X/X (X.X.X.X/X) to
> identity:X.X.X.X/X (X.X.X.X/X)</test_message>
>
> </example>
>
> </examples>
>
> </rule>
>
> <rule id='20aee256-b4f0-8b4d-93cb-263d5338fd21'
> class='system' provider='%ASA'>
>
> <!-- support: 1539 -->
>
> <patterns>
>
> <pattern>Teardown @ESTRING:Protocol: @connection
> @ESTRING:: @for @ESTRING:::@@IPv4:SrcIP:/@@ESTRING:SrcPort: @to
> identity:@IPv4:DstIP:/@@ESTRING:DstPort:
> @duration at ANYSTRING::@</pattern>
>
> </patterns>
>
> <examples>
>
> <example>
>
> <test_message program='%ASA'>Teardown UDP
> connection 55101084 for inside:X.X.X.X/X to identity:X.X.X.X/X
> duration 0:02:01 bytes 88</test_message>
>
> </example>
>
> </examples>
>
> </rule>
>
> <rule id='e075efdc-c25f-5e49-a208-7661e3b5a29b'
> class='system' provider='%ASA'>
>
> <!-- support: 3648 -->
>
> <patterns>
>
> <pattern>Built dynamic @ESTRING:Protocol: @translation
> from @ESTRING:::@@IPv4:LocalIP:/@@ESTRING:LocalPort: @to
> @ESTRING:::@@IPv4:GlobalIP:/@@ESTRING:GlobalPort:@</pattern>
>
> </patterns>
>
> <examples>
>
> <example>
>
> <test_message program='%ASA'>Built dynamic TCP
> translation from any:X.X.X.X/X to outside:X.X.X.X/X</test_message>
>
> </example>
>
> </examples>
>
> </rule>
>
> <rule provider='%ASA' class='system' id='39'>
>
> <patterns>
>
> <pattern>Cleared @ESTRING:: @urgent flag from
> @ESTRING:::@@ESTRING::/@@NUMBER::@ to @ESTRING:
> ::@@ESTRING::/@@NUMBER::@</pattern>
>
> <pattern>regular translation creation failed for
> @ESTRING:: @src @ESTRING:::@@ESTRING:: @dst @ESTRING:
> ::@@ESTRING:: @(type @NUMBER::@, code @NUMBER::@</pattern>
>
> </patterns>
>
> </rule>
>
> </rules>
>
> </ruleset>
>
> </patterndb>
>
>
>
> N�n�r����)em�h�yhiם�w^��
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