SYNOPSIS
lr_anonymize dumpfilestemDESCRIPTION
lr_anonymize is typically used when sending logs to a responder. See the section on ``Sending Anonymized Log Files To A Responder'' in the chapter on ``Using A Responder'' in the Lire User Manual for usage examples.lr_anonymize reads a file containing emailaddresses, ipnumbers, and hostnames (typically a logfile from an internet service) from stdin, and prints an ``anonymized'' version of this file to stdout. It dumps the information to ``deanonymize'' the file, using lr_deanonymize(1), to 5 Berkeley DB databases; the names of the files holding these databases is contructed by concatenating the strings 'inaddr', 'maildomain', 'email', 'ip' and 'domain' to dumpfilestem. dumpfilestem can be e.g. /tmp/dump, ../../var/dump or dump. The db files created silently overwrite stale ones, if found.
The script builds temporary files. By default, these are created in /tmp. One can override this by setting the TMPDIR environment variable.
CONNECTION WITH lr_deanonymize
When running
$ lr_anonymize dump < log > log.anon $ lr_deanonymize dump < log.anon > log.new
then log and log.new have the same content (except for case, check it with diff -i).
NOTES
We tried to optimize this script for memoryusage. This has the drawback the script will run for quite some time when anonymizing a big logfile.We've run the script on a 25 M sendmail logfile.
Typical values in such a case are 2500 K for total amount of physical memory used, and 15m real, 8m user and 22s systime spent on a 64 MB system with a 300 MHz Pentium II processor. de_anonymizing this file took 11m real, 8m user and 17s system time.
We store maildomains in the dumpfile. These are used by lr_deanonymize(1), in case email addresses in our input file reoccur in the file read by lr_deanonymize(1) in split form, i.e. [email protected] occurs as both [email protected] and example.com in the to be deanonymized file.
All dumped objects are casted to lowercase.
BACKGROUND
For your convenience, we quote a bit of rfc822:
SPACE = <ASCII SP, space> ; ( 40, 32.)
CTL = <any ASCII control ; ( 0- 37, 0.- 31.)
character and DEL> ; ( 177, 127.)
specials = "(" / ")" / "<" / ">" / "@" ; Must be in quoted-
/ "," / ";" / ":" / "\" / <"> ; string, to use
/ "." / "[" / "]" ; within a word.
atom = 1*<any CHAR except specials, SPACE and CTLs>
quoted-string = <"> *(qtext/quoted-pair) <">; Regular qtext or
; quoted chars.
word = atom / quoted-string
domain-ref = atom ; symbolic reference
domain-literal = "[" *(dtext / quoted-pair) "]"
sub-domain = domain-ref / domain-literal
domain = sub-domain *("." sub-domain)
local-part = word *("." word) ; uninterpreted
; case-preserved
addr-spec = local-part "@" domain ; global address
and of rfc 2181
The DNS itself places only one restriction on the particular labels that can be used to identify resource records. That one restriction relates to the length of the label and the full name. The length of any one label is limited to between 1 and 63 octets. A full domain name is limited to 255 octets (including the separators).
rfc1123
However, a valid host name can never have the dotted-decimal form #.#.#.#, since at least the highest-level component label will be alphabetic.
rfc819
<domain> ::= <naming-domain> | <naming-domain> "." <domain> <naming-domain> ::= <simple-name> | <address> <simple-name> ::= <a> <ldh-str> <let-dig> <ldh-str> ::= <let-dig-hyp> | <let-dig-hyp> <ldh-str> <let-dig> ::= <a> | <d> <let-dig-hyp> ::= <a> | <d> | "-" <a> ::= any one of the 52 alphabetic characters A through Z in upper case and a through z in lower case <d> ::= any one of the ten digits 0 through 9
EXAMPLE
A 'logfile' like e.g.
blaat fkrf 1.2.3.4.in-addr.arpa] [email protected] bla 1 2 3 lj;agas;gag blaat 1.2.3.4 fkrf 3.2.3.4.in-addr.arpa] bla 1 www.hotsex.com 2 3 lj;agas;gag [email protected] agagag blaat fkrf 4.2.3.4.in-addr.arpa] bla [email protected] www.hotsex.com 234.34.2.0 [email protected] 4.2.3.4.in-addr.arpa1 2 3 lj;agas;gag blaat fkrf tweede 3.2.3.4.in-addr.arpa] bla 1.2.3.4 1 blablabla.com 2 mdcc.cx 3 lj;agas;gag
wil get anonymized to
blaat fkrf 1.0.0.10.in-addr.arpa] [email protected] bla 1 2 3 lj;agas;gag blaat 10.0.0.1 fkrf 2.0.0.10.in-addr.arpa] bla 1 1.example.com 2 3 lj;agas;gag [email protected] agagag blaat fkrf 3.0.0.10.in-addr.arpa] bla [email protected] 1.example.com 10.0.0.2 [email protected] 3.0.0.10.in-addr.arpa1 2 3 lj;agas;gag blaat fkrf tweede 2.0.0.10.in-addr.arpa] bla 10.0.0.1 1 2.example.com 2 3.example.com 3 lj;agas;gag
The dumps will represent something like
ip 234.34.2.0 10.0.0.2 ip 1.2.3.4 10.0.0.1 inaddr 3.2.3.4.in-addr.arpa 2.0.0.10.in-addr.arpa inaddr 1.2.3.4.in-addr.arpa 1.0.0.10.in-addr.arpa inaddr 4.2.3.4.in-addr.arpa 3.0.0.10.in-addr.arpa domain mdcc.cx 3.example.com domain blablabla.com 2.example.com domain www.hotsex.com 1.example.com email [email protected] [email protected] email [email protected] [email protected]
BUGS
We can't handle files containing hostnames or email addresses in the example.com domain, usernames of the form john.doe.<someletters> or ipnumbers in the rfc 1918 private network 10.0.0.0 - 10.255.255.255 (10/8 prefix).We don't handle quoted-string's in email addresses. We don't handle domain-literals in email addresses' domain.
We regard 999.999.999.999 as an IP address: we don't mind the 255 limit.
We don't treat network ipaddresses like 100.10.3 as ipaddresses. These will not get anonymized.
VERSION
$Id: lr_anonymize.in,v 1.5 2006/07/23 13:16:32 vanbaal Exp $COPYRIGHT
Copyright (C) 2000-2001 Stichting LogReport Foundation [email protected]This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with this program (see COPYING); if not, check with http://www.gnu.org/copyleft/gpl.html.