Erre con erre cigarro
Erre con erre barril
Rápido ruedan los carros
En el ferrocarril
NAME
maradns - DNS server
SYNOPSIS
maradns [ -v | -f mararc_file_location ]
TABLE OF CONTENTS
This man page has the following sections:
Name
Synopsis
Table of Contents
Description
Usage
Firewall Configuration
Frequently Asked Questions
Bugs
Unimplemented Features
Legal Disclaimer
Authors
DESCRIPTION
maradns is a DNS server written with security, simplicity, and
performance in mind.
maradns has two forms of arguments, both of which are optional.
The first is the location of a mararc file which MaraDNS obtains
all configuration information from. The default location of this
file is /etc/mararc. This is specified in the form maradns -f
mararc_file_location; mararc_file_location is the location of
the mararc file.
It is also possible to have MaraDNS display the version number
and exit. This is specified by invoking maradns in the form
maradns -v or maradns --version
USAGE
If MaraDNS is functioning only as a recursive nameserver, just
one file needs to be set up: The mararc file.
In order for MaraDNS to function as an authoritative nameserver,
two or more files need to be set up: the mararc file and one or
more "csv2" (or "csv1") zone files.
The format of a csv2 zone file can be obtained from the csv2(5)
manual page. The configuration format of the mararc file can be
obtained from the mararc(5) manual page.
In order to have MaraDNS run as a daemon, the duende program is
used to daemonize MaraDNS. See the duende(8) manual page for
details.
FIREWALL CONFIGURATION
If MaraDNS is being used as an authoritative nameserver, allow
UDP connections from all hosts on the internet to UDP port 53
for the IP that the authoritative nameserver uses.
If MaraDNS is being used as a recursive nameserver, the firewall
needs to allow the following packets to go to and from the IP
the recursive nameserver uses:
* Allow UDP connections from the MaraDNS-running server to any
machine on the internet where the UDP destination port is 53
* Allow UDP connections from any machine on the internet to
the IP of the recursive server, where the source port from
the remote server is 53, and the destination port is between
15000 and 19095 (inclusive)
* Allow UDP connections from IPs that use MaraDNS as a
recursive DNS server to port 53 of the MaraDNS server
MaraDNS uses a strong secure RNG for both the query (16 bits of
entropy) and the source port of the query (12 bits of entropy).
This makes spoofing replies to a MaraDNS server more difficult,
since the attacker has only a one in 250 million chance that a
given spoofed reply will be considered valid.
FREQUENTLY ASKED QUESTIONS
INDEX
1. I'm using an older version of MaraDNS
2. How do I try out MaraDNS?
3. What license is MaraDNS released under?
4. How do I report bugs in MaraDNS?
5. Some of the postings to the mailing list do not talk
about MaraDNS!
6. How do I get off the mailing list?
7. How do I set up reverse DNS on MaraDNS?
8. I am on a slow network, and MaraDNS can not process
recursive queries
9. When I try to run MaraDNS, I get a cryptic error
message.
10. After I start MaraDNS, I can not see the process when
I run netstat -na
11. What string library does MaraDNS use?
12. Why does MaraDNS use a multi-threaded model?
13. I feel that XXX feature should be added to MaraDNS
14. I feel that MaraDNS should use another documentation
format
15. Is there any process I need to follow to add a patch
to MaraDNS?
16. Can MaraDNS act as a primary nameserver?
17. Can MaraDNS act as a secondary nameserver?
18. What is the difference between an authoritative and a
recursive DNS server?
19. The getzone client isn't allowing me to add certain
hostnames to my zone
20. Is MaraDNS portable?
21. Can I use MaraDNS in Windows?
22. MaraDNS freezes up after being used for a while
23. What kind of Python integration does MaraDNS have
24. Doesn't "kvar" mean "four" in Esperanto?
25. How scalable is MaraDNS?
26. I am having problems setting upstream_servers
27. Why doesn't the MaraDNS.org web page validate?
28. How do MX records work?
29. Does MaraDNS have support for SPF?
30. I'm having problems resolving CNAMES I have set up.
31. I have a NS delegation, and MaraDNS is doing strange
things.
32. I am transferring a zone from another server, but the
NS records are these strange "synth-ip" records.
33. Where is the root.hints file?
34. Are there any plans to use autoconf to build MaraDNS?
35. How do I change the compiler or compile-time flags
with MaraDNS' build process?
36. Will you make a package for the particular Linux
distribution I am using?
37. I am using the native Windows port of MaraDNS, and
some features are not working.
38. MaraDNS isn't starting up
39. You make a lot of releases of MaraDNS; at our ISP/IT
department, updating software is non-trivial.
40. I have star records in my zones, and am having
problems with NXDOMAINs/IPV6 resolution
41. I have a zone with only SOA/NS records, and the zone
is not working.
42. I am having problems registering my domain with AFNIC
(the registrar for .fr domains)
43. I can't see the full answers for subdomains I have
delegated
44. MaraDNS 1 has a problem resolving a domain
45. MaraDNS 1.2 has issues with NXDOMAINS and case
sensitivity.
46. Can MaraDNS offer protection from phishing and
malicious sites?
47. Does maradns support star (wildcard) records?
48. I'm having problems using MaraDNS with some *NIX
command line applications like telnet
49. My virus scanner reports that MaraDNS or Deadwood has
a virus
50. I can not subscribe to the MaraDNS mailing list
51. How does MaraDNS respond to EDNS (RFC2671) packets?
52. How to I get MaraDNS to always give the same IP to all
DNS queries?
ANSWERS
1. I'm using an older version of MaraDNS
Upgrade to MaraDNS 1.4. MaraDNS 1.4 is compatible with older
versions of MaraDNS, with the relatively few changes need to
upgrade documented.
MaraDNS 1.0 and 1.2 are only supported for critical security
updates, and will no longer be supported on December 21, 2010.
MaraDNS 1.3 is also only supported for critical security
updates, and support will stop on December 21, 2012. MaraDNS 1.4
will be fully supported (security and other important bug fixes)
for the foreseeable future, alongside MaraDNS 2.0 when and if it
comes out.
2. How do I try out MaraDNS?
Read the quick start guide, which is the file named
0QuickStart in the MaraDNS distribution.
3. What license is MaraDNS released under?
MaraDNS 1.2 is released with the following two-clause BSD-type
license:
Copyright (c) 2002-2009 Sam Trenholme and others
TERMS
Redistribution and use in source and binary forms, with or
without modification, are permitted provided that the
following conditions are met:
1. Redistributions of source code must retain the above
copyright notice, this list of conditions and the following
disclaimer.
2. Redistributions in binary form must reproduce the above
copyright notice, this list of conditions and the following
disclaimer in the documentation and/or other materials
provided with the distribution.
This software is provided 'as is' with no guarantees of
correctness or fitness for purpose.
4. How do I report bugs in MaraDNS?
Send an email to the MaraDNS mailing list. Details on how to do
this are at http://www.maradns.org/
5. Some of the postings to the mailing list do not talk about MaraDNS!
Topic drift sometimes happens. It's a part of life.
6. How do I get off the mailing list?
Send an email to list-request@maradns.org with "unsubscribe" as
the subject line.
7. How do I set up reverse DNS on MaraDNS?
Reverse DNS (sometimes called "reverse mapping") is set up by
using PTR (pointer) records. For example, the PTR record which
performs the reverse DNS lookup for the ip 10.2.3.4 looks like
this in a CSV2 zone file:
4.3.2.10.in-addr.arpa. PTR www.example.com.
It is also possible to use a special "FQDN4" which automatically
sets up the reverse mapping of a given record:
www.example.com. FQDN4 10.2.3.4
If you wish to have a PTR (reverse DNS lookup; getting a DNS
name from a numeric IP) record work on the internet at large, it
is not a simple matter of just adding a record like this to a
MaraDNS zonefile. One also needs control of the appropriate
in-addr.arpa. domain.
While it can make logical sense to contact the IP 10.11.12.13
when trying to get the reverse DNS lookup (fully qualified
domain name) for a given IP, DNS servers don't do this. DNS
server, instead, contact the root DNS servers for a given
in-addr.arpa name to get the reverse DNS lookup, just like they
do with any other record type.
When an internet service provider is given a block of IPs, they
are also given control of the DNS zones which allow them to
control reverse DNS lookups for those IPs. While it is possible
to obtain a domain and run a DNS server without the knowledge or
intervention of an ISP, being able to control reverse DNS
lookups for those IPs requires ISP intervention.
8. I am on a slow network, and MaraDNS can not process recursive
queries
MaraDNS, by default, only waits two seconds for a reply from a
remote DNS server. This default can be increased by adding a
line like this in the mararc file:
timeout_seconds = 5
Note that making this too high will slow MaraDNS down when DNS
servers are down, which is, alas, all too common on today's
internet.
9. When I try to run MaraDNS, I get a cryptic error message.
There is usually some context of where there is a syntax error
in a data file before the cryptic error message. For example,
when there is a syntax error in a csv2 zone file, MaraDNS will
tell you exactly at what point it had to terminate parsing of
the zone file.
If MaraDNS does return a cryptic error message without letting
you know what is wrong, let us know on the mailing list so that
we can fix the bug. MaraDNS is designed to be easy to use;
cryptic error messages go against this spirit.
10. After I start MaraDNS, I can not see the process when I run
netstat -na
Udp services do not have a prominent "LISTEN" when netstat is
run.
When MaraDNS is up, the relevant line in the netstat output
looks like this: udp 0 0 127.0.0.1:53 0.0.0.0:*
While on the topic of netstat, if you run netstat -nap as root
on Linux and some other *nix operating systems, you can see the
names of the processes which are providing internet services.
11. What string library does MaraDNS use?
MaraDNS uses its own string library, which is called the
"js_string" library. Man pages for most of the functions in the
js_string library are in the folder doc/man of the MaraDNS
distribution
12. Why does MaraDNS use a multi-threaded model?
The multi-threaded model is, plain and simple, the simplest way
to write a functioning recursive DNS server. There is a reason
why MaraDNS, pdnsd, and BIND 9 all use the multi-threaded model.
MaraDNS 2.0, when and if it is released, will not use threads.
13. I feel that XXX feature should be added to MaraDNS
The only thing that will convince me to implement a given
feature for MaraDNS is cold, hard cash. If you want me to keep a
given feature proprietary, you better have lots of cold hard
cash.
The only feature I will implement for free is to finish up full
recursion in Deadwood, including IPv6 support. I have no
plans to implement DNS curve, nor DNSsec, Geo IP, or
whatever feature you want me to implement for fun and for free.
Keep in mind that both the BIND and NSD name servers were
developed by having the programmers paid to work on the
programs. PowerDNS was originally commercial software with the
author only reluctantly made GPL after seeing that the market
for a commercial DNS server is very small. All of the other DNS
servers which have been developed as hobbyist projects (Posadis,
Pdnsd, and djbdns) are no longer being actively worked on by the
primary developer.
14. I feel that MaraDNS should use another documentation format
The reason that MaraDNS uses its own documentation format is to
satisfy both the needs of translators to have a unified document
format and my own need to use a documentation format that is
simple enough to be readily understood and which I can add
features on an as needed basis.
The documentation format is essentially simplified HTML with
some special tags added to meet MaraDNS' special needs.
This gives me more flexibility to adapt the documentation format
to changing needs. For example, when someone pointed out that
it's not a good idea to have man pages with hi-bit characters,
it was a simple matter to add a new HIBIT tag which allows man
pages to be without hi-bit characters, and other document
formats to retain hi-bit characters.
Having a given program have its own documentation format is not
without precedent; Perl uses its own "pod" documentation format.
15. Is there any process I need to follow to add a patch to MaraDNS?
Yes.
Here is the procedure for making a proper patch:
* Enter the directory that the file is in, for example
maradns-1.4.01/server
* Copy over the file that you wish to modify to another file
name. For example: cp MaraDNS.c MaraDNS.c.orig
* Edit the file in question, e.g: vi MaraDNS.c
* After editing, do something like this:
diff -u MaraDNS.c.orig MaraDNS.c > maradns.patch
* Make sure the modified version compiles cleanly
Send a patch to the MaraDNS mailing list, along with a statement
that you place the contents of the patch under MaraDNS' BSD
license. If I find that the patch works well, I will integrate
it in to MaraDNS.
16. Can MaraDNS act as a primary nameserver?
Yes.
The zoneserver program serves zones so that other DNS servers
can be secondaries for zones which MaraDNS serves. This is a
separate program from the maradns server, which processes both
authoritative and recursive UDP DNS queries.
See the DNS master document in the MaraDNS tutorial for
details.
17. Can MaraDNS act as a secondary nameserver?
Yes.
Please read the DNS slave document, which is part of the
MaraDNS tutorial.
18. What is the difference between an authoritative and a recursive
DNS server?
A recursive DNS server is a DNS server that is able to contact
other DNS servers in order to resolve a given domain name label.
This is the kind of DNS server one points to in
/etc/resolve.conf
An authoritative DNS server is a DNS server that a recursive
server contacts in order to find out the answer to a given DNS
query.
19. The fetchzone client isn't allowing me to add certain hostnames to
my zone
For security reasons, MaraDNS' fetchzone client does not add
records which are not part of the zone in question. For example,
if someone has a zone for example.com, and this record in the
zone:
1.1.1.10.in-addr.arpa. PTR dns.example.com.
MaraDNS will not add the record, since the record is
out-of-bailiwick. In other words, it is a host name that does
not end in .example.com.
There are two workarounds for this issue:
* Create a zone file for 1.1.10.in-addr.arpa., and put the PTR
records there.
* Use rcp, rsync, or another method to copy over the zone
files in question.
20. Is MaraDNS portable?
MaraDNS is developed on a CentOS 5 and Windows XP dual boot
laptop. MaraDNS may or may not compile and run on other systems.
21. Can I use MaraDNS in Windows?
Yes. There is both a partial mingw32 (native win32 binary) port
and a full Cygwin port of MaraDNS; both of these ports are part
of the native build of MaraDNS. Deadwood has full Windows
support, including the ability to run as a service.
22. MaraDNS freezes up after being used for a while
There is a bug with the Linux kernel which causes UDP clients to
freeze unless code is written to work around the kernel bug.
This workaround was first introduced in MaraDNS 1.0.28 and
1.1.35 and accidently disabled in 1.2.03.1.
If using your ISP's name servers or some other name servers
which are not, in fact, root name servers, please make sure that
you are using the upstream_servers dictionary variable instead
of the root_servers dictionary variable.
If you still see MaraDNS freeze up after making this correction,
please send a bug report to the mailing list.
23. What kind of Python integration does MaraDNS have
The mararc file uses the same syntax that Python uses; in fact,
Python can parse a properly formatted mararc file.
There is currently no other integration with Python.
24. Doesn't "kvar" mean "four" in Esperanto?
Indeed, it does. However the use of "kvar" in the MaraDNS source
code only coincidentally is an Esperanto word. "kvar" is short
for "Kiwi variable"; a lot of the parsing code comes from the
code used in the Kiwi spam filter project.
25. How scalable is MaraDNS?
MaraDNS is optimized for serving a small number of domains as
quickly as possible. That said, MaraDNS is remarkably efficnent
for serving a large number of domains, as long as the server
MaraDNS is on has the memory to fit all of the domains, and as
long as the startup time for loading a large number of domains
can be worked around.
The "big-O" or "theta" growth rates for various MaraDNS
functions are as follows, where N is the number of authoritative
host names being served:
Startup time N
Memory usage N
Processing incoming DNS requests 1
As can be seen, MaraDNS will process 1 or 100000 domains in the
same amount of time, once the domain names are loaded in to
memory.
26. I am having problems setting upstream_servers
The upstream_servers mararc variable is set thusly:
upstream_servers["."] = "10.3.28.79, 10.2.19.83"
Note the ["."]. The reason for this is so future versions of
MaraDNS may have more fine-grained control over the
upstream_servers and root_servers values.
Note that the upstream_servers variable needs to be initialized
before being used via upstream_servers = {} (the reason for this
is so that a mararc file has 100% Python-compatible syntax). A
complete mararc file that uses upstream_servers may look like
this:
ipv4_bind_addresses = "127.0.0.1"
chroot_dir = "/etc/maradns"
recursive_acl = "127.0.0.1/8"
upstream_servers = {}
upstream_servers["."] = "10.1.2.3, 10.2.4.6"
27. Why doesn't the MaraDNS.org web page validate?
HTML pages on the MaraDNS.org web site should validate as HTML
4.0 Transitional. However, the CSS will not validate.
I have designed MaraDNS' web page to be usable and as attractive
as possible in any major browser released in the last ten years.
Cross-browser support is more important than strict W3
validation. The reason why the CSS does not validate is because
I need a way to make sure there is always a scrollbar on the web
page, even if the content is not big enough to merit one; this
is to avoid the content jumping from page to page. There is no
standard CSS tag that lets me do this. I'm using a non-standard
tag to enable this in Gecko (Firefox's rendering engine); this
is enabled by default in Trident (Internet Explorer's rendering
engine). The standards are deficient and blind adherence to them
would result in an inferior web site.
There are also two validation warnings generated by
redefinitions which are needed as part of the CSS filters used
to make the site attractive on older browsers with limited CSS
support.
On a related note, the reason why I use tables instead of CSS
for some of the layout is because Microsoft Internet Explorer 6
and other browsers do not have support for the max-width CSS
property. Without this property, the web page will not scale
down correctly without using tables. Additionally, tables allow
a reasonably attractive header in browsers without CSS support.
28. How do MX records work?
How MX records work:
* The mail transport agent (Sendmail, Postfix, Qmail, MS
Exchange, etc.) looks up the MX record for the domain
* For each of the records returned, the MTA (mail transport
agent) looks up the IP for the names.
* It will choose, at random, any of the MXes with the lowest
priority number.
* Should that server fail, it will try another server with the
same priority number.
* Should all MX records with a given priority number fail, the
MTA will try sending email to any of the MX records with the
second-lowest priority value.
As an aside, do not have MX records point to CNAMEs.
29. Does MaraDNS have support for SPF?
SPF, or sender policy framework, is method of using DNS that
makes it more difficult to forge email. MaraDNS has full support
for SPF, both via TXT records and, starting with MaraDNS 1.2.08,
via RFC4408 SPF records.
SPF configuration is beyond the scope of MaraDNS' documentation.
However, at the time of this FAQ entry being written (June,
2006), information and documentation concerning SPF is available
at http://openspf.org. The BIND examples will work in
MaraDNS csv2 zone files as long as the double quotes (") are
replaced by single quotes ('). For example, a SPF TXT record
that looks like example.net. IN TXT "v=spf1 +mx
a:colo.example.com/28 -all" in a BIND zone file will look like
example.net. TXT 'v=spf1 +mx a:colo.example.com/28 -all' in a
MaraDNS zone file. MaraDNS version 1.2.08 and higher can also
make the corresponding SPF record, which will have the syntax
example.net. SPF 'v=spf1 +mx a:colo.example.com/28 -all'.
30. I'm having problems resolving CNAMES I have set up.
This is probably because you have set up what MaraDNS calls a
dangling CNAME record.
Let us suppose we have a CNAME record without an A record in the
local DNS server's database, such as:
google.example.com. CNAME www.google.com.
This record, which is a CNAME record for "google.example.com",
points to "www.google.com". Some DNS servers will recursively
look up www.google.com, and render the above record like this:
google.example.com. CNAME www.google.com.
www.google.com. CNAME 66.102.7.104
For security reasons, MaraDNS doesn't do this. Instead, MaraDNS
will simply output:
google.example.com. CNAME www.google.com.
Some stub resolvers will be unable to resolve google.example.com
as a consequence.
If you set up MaraDNS to resolve CNAMEs thusly, you will get a
warning in your logs about having a dangling CNAME record.
If you want to remove these warnings, add the following to your
mararc file:
no_cname_warnings = 1
Information about how to get MaraDNS to resolve dangling CNAME
records is in the tutorial file dangling.html
31. I have a NS delegation, and MaraDNS is doing strange things.
In the case of there being a NS delegation, MaraDNS handles
recursive queries and non-recursive DNS queries differently.
Basically, unless you use askmara with the -n option, dig with
the +norecuse option, or nslookup with the -norec option,
MaraDNS will try to recursively resolve the record that is
delegated.
The thinking is this: A normal recursive DNS query is usually
one where one wants to know the final DNS output. So, if MaraDNS
delegates a given record to another DNS server, and gets a
recursive request for said query, MaraDNS will recursively
resolve the query for you.
For example, let us suppose we have a mararc file that looks
like this:
chroot_dir = "/etc/maradns"
ipv4_bind_addresses = "10.1.2.3"
chroot_dir = "/etc/maradns"
recursive_acl = "127.0.0.1/8, 10.0.0.0/8"
csv2 = {}
csv2["example.com."] = "db.example.com"
And a db.example.com file that looks like this:
www.example.com. 10.1.2.3
joe.example.com. NS ns.joe.example.com.
ns.joe.example.com. A 10.1.2.4
Next, you are trying to find out why www.joe.example.com is not
resolving. If you naively send a query to 10.1.2.3 for
www.joe.example.com as askmara Awww.joe.example.com. 10.1.2.3 or
as dig @10.1.2.3 www.joe.example.com. or as nslookup
www.joe.example.com. 10.1.2.3, you will not get any information
that will help you solve the problem, since 10.1.2.3 will try to
contact 10.1.2.4 to resolve www.joe.example.com.
The solution is to run your DNS query client thusly:
* Askmara would be run thusly:
askmara -n Awww.joe.example.com. 10.1.2.3
* Dig would be run thusly:
dig +norecurse @10.1.2.3 www.joe.example.com
* Nslookup would be run thusly:
nslookup -norec www.joe.example.com 10.1.2.3
This will allow you to see that packets MaraDNS actually sends
to a recursive DNS server.
As an aside, this particular problem will not happen if MaraDNS
is run only as an authoritative nameserver.
32. I am transferring a zone from another server, but the NS records
are these strange "synth-ip" records.
MaraDNS expects, in csv2 zone files, for all delegation NS
records to be between the SOA record and the first non-NS
record.
If a zone looks like this:
example.net. +600 soa ns1.example.net.
hostmaster@example.net 10 10800 3600 604800 1080
example.net. +600 mx 10 mail.example.net.
example.net. +600 a 10.2.3.5
example.net. +600 ns ns1.example.net.
example.net. +600 ns ns3.example.net.
mail.example.net. +600 a 10.2.3.7
www.example.net. +600 a 10.2.3.11
Then the NS records will be "synth-ip" records.
The zone should look like this:
example.net. +600 soa ns1.example.net.
hostmaster@example.net 10 10800 3600 604800 1080
example.net. +600 ns ns1.example.net.
example.net. +600 ns ns3.example.net.
example.net. +600 mx 10 mail.example.net.
example.net. +600 a 10.2.3.5
mail.example.net. +600 a 10.2.3.7
www.example.net. +600 a 10.2.3.11
This will remove the "synth-ip" records.
To automate this process, this awk script is useful:
fetchzone whatever.zone.foo 10.1.2.3 | awk '
{if($3 ~ /ns/ || $3 ~ /soa/){print}
else{a = a "\n" $0}}
END{print a}' > zonefile.csv2
Replace "whatever.zone.foo" with the name of the zone you are
fetchin 10.1.2.3 with the IP address of the DNS master, and
zonefile.csv2 with the name of the zone file MaraDNS loads.
33. Where is the root.hints file?
MaraDNS, unlike BIND, does not need a complicated root.hints
file in order to have custom root servers. In order to change
the root.hints file, add something like this to your mararc
file:
root_servers["."] = "131.161.247.232,"
root_servers["."] += "208.185.249.250,"
root_servers["."] += "66.227.42.140,"
root_servers["."] += "66.227.42.149,"
root_servers["."] += "65.243.92.254"
Note that there is no "+=" in the first line, and the last line
does not have a comma at the end. Read the recursive tutorial
document for more information.
34. Are there any plans to use autoconf to build MaraDNS?
No. OK, let me qualify that: I won't do it unless you pay me
enough money.
In more detail, MaraDNS does not use autoconf for the following
reasons:
* Autoconf is designed to solve a problem that existed in the
mid 1990s but does not exist today: A large number of
different incompatible C compilers and libc implementations.
These days, most systems are using gcc as the compiler and
some version of glibc as the libc. There is no longer a
need, for example, to figure out whether a given
implementation of getopt() allows '--' options. MaraDNS's
./configure script can be run in only a second or two;
compare this to the 3-5 minute process autoconf's
./configure needs.
* Autoconf leaves GPL-tained files in a program's build tree.
MaraDNS is licensed under a BSD license that is not
GPL-compatible, so MaraDNS can not be distributed with these
GPL-licensed files.
This leads us to the next question:
35. How do I change the compiler or compile-time flags with MaraDNS'
build process?
To change the compiler used by MaraDNS:
* Run the ./configure script
* Open up the file Makefile with an editor
* Look for a line that starts with CC
* If there is no line that starts with CC, create one just
before the line that starts with FLAGS
* Change (or create) that line to look something like
CC=gcc296 In this example, the 2.96 version of gcc is used
to compile MaraDNS.
* Note that it is important to not remove anything from this
line you do not understand; doing so will make MaraDNS
unable to compile or run. So, if the CC line looks like
CC=gcc $(LDFLAGS) -DNO_FLOCK and you want to compile with
gcc 2.96, change the line to look like
CC=gcc296 $(LDFLAGS) -DNO_FLOCK retaining the flags added by
the configuration script.
Changing compile-time flags is a similar process:
* Run the ./configure script
* Open up the file Makefile with an editor
* Look for a line that starts with FLAGS
* Change (or create) that line to look something like
FLAGS=-O3 In this example, MaraDNS is compiled with the -O3
option.
* Note that it is important to not remove anything from this
line you do not understand; doing so will make MaraDNS
unable to compile or run. So, if the FLAGS line looks like
FLAGS=-O2 -Wall -DSELECT_PROBLEM and you want to compile at
optimization level three, change this line to look like
FLAGS=-O2 -Wall -DSELECT_PROBLEM retaining the flags added
by the configuration script. -DSELECT_PROBLEM for example,
is needed in the Linux compile or MaraDNS will have problems
with freezing up.
36. Will you make a package for the particular Linux distribution I am
using?
No. OK, let me qualify that: I won't do it unless you pay me
enough money.
There is, however, a CentOS 5-compatible RPM spec file in the
build directory.
37. I am using the native Windows port of MaraDNS, and some features
are not working.
Since Windows 32 does not have some features that *NIX OSes
have, the native Windows port does not have all of the features
of the *NIX version of MaraDNS. In particular, the following
features are disabled:
* ipv6 (this is actually a mingw32, not a Windows deficiency)
* The chroot_dir mararc variable
* The maradns_gid and maradns_uid mararc variables
* The maxprocs mararc variable
* The synth_soa_serial variable can not have a value of 2
If any of the above features are desired, try compiling MaraDNS
using Cygwin. Note that the Cygwin port of MaraDNS does not have
ipv6 support, and that while chroot_dir works in Cygwin, it does
not have the security that the *NIX chroot() call has.
38. MaraDNS isn't starting up
This is usually caused by a syntax error in one's mararc file,
or by another MaraDNS process already running. To see what is
happening, look at your system log (/var/log/messages in Centos
3) to see what errors MaraDNS reports. If you do not know how to
look at a system log, you can also invoke MaraDNS from the
command line as root; any errors will be visible when starting
MaraDNS.
39. You make a lot of releases of MaraDNS; at our ISP/IT department,
updating software is non-trivial.
The number of releases seen in the changelog is not an
accurate reflection of how often someone using a stable branch
of MaraDNS will need to update.
MaraDNS 1.2 and 1.3.07, the older stable branches of MaraDNS,
were last updated in August of 2008.
I go to a great deal of effort to make sure MaraDNS releases are
as painless to update as possible. I ensure configuration file
format compatibility, even between major versions of MaraDNS.
With the exception of configuration file parser bugfixes,
MaraDNS 1.0 configuration files are compatible with MaraDNS 1.4.
It is impossible to make code that is bug-free or without
security problems. This is especially true with code that runs
on the public internet.^1 Code has to be updated from time to
time. What I do in order to minimize the disruption caused by an
update is to always have a stable bugfix-only branch of MaraDNS
(right now I have two bugfix-only branches), and to, as much as
possible, evenly space out the bugfix updates.
Footnote 1: Even DJB's code has security problems. Both Qmail
and DjbDNS have known security problems, and need to be patched
before put on a public internet server.
40. I have star records in my zones, and am having problems with
NXDOMAINs/IPV6 resolution
This was a bug in MaraDNS 1.2 which has long since been fixed.
41. I have a zone with only SOA/NS records, and the zone is not
working.
MaraDNS 1.2 has a bug where it does not correctly process zones
without any "normal" records. For example, suppose a zone like
this:
% SOA localhost. root@localhost. 1 7200 600 1209600 3600
% NS localhost.
This zone will not work until some non-SOA/NS record is added,
such as in this zone file:
% SOA localhost. root@localhost. 1 7200 600 1209600 3600
% NS localhost.
foo.% TXT 'MaraDNS 1.2 needs this record.'
This bug has been fixed in MaraDNS 1.3 and 1.4; since this is
not a security bug (there is a perfectly good workaround), this
bug will not be fixed in MaraDNS 1.2 unless you pay me to fix
it.
42. I am having problems registering my domain with AFNIC (the
registrar for .fr domains)
Because of an issue with AFNIC (who, annoyingly enough, check
the RA bit when registering a domain), in order to register a
domain with AFNIC using MaraDNS as your DNS server, the
following steps need to be followed:
* MaraDNS version 1.4 needs to be used; if you're using an
older version of MaraDNS, upgrade.
* It is necessary to have recursion disabled. This can be done
either by compiling MaraDNS without recursive support
(./configure --authonly ; make), or by making sure MaraDNS
does not have recursion enabled (by not having recursive_acl
set in one's mararc file)
If one wishes to both register domains with AFNIC and use
MaraDNS as a recursive DNS server, it is required to have the
recursive server be a separate instance of MaraDNS on a separate
IP. It is not possible to have the same DNS server both send DNS
packets in a way that both makes AFNIC happy and allows
recursive queries.
Note also: AFNIC gives warnings about reverse DNS lookups; more
information about this issue can be found in the FAQ entry
about reverse DNS mappings (question 7). In addition, AFNIC
requires DNS-over-TCP to work; information on configuring
MaraDNS to have this can be found in the DNS-over-TCP
tutorial.
43. I can't see the full answers for subdomains I have delegated
To have the subdomains be visible to recursive nameservers, add
the following to your mararc file:
recurse_delegation = 1
44. MaraDNS 1 has a problem resolving a domain
This issue should be fixed when I release MaraDNS 2.0.
Here's what happening: I have rewritten the recursive resolver
for MaraDNS. The old code was always designed to be a
placeholder until I wrote a new recursive resolver.
The new recursive resolver is called "Deadwood"; right now it's
fully functional and undergoing beta-testing. More information
is here:
http://maradns.blogspot.com/search/label/Deadwood
http://maradns.org/deadwood/
Since the old recursive code is a bit difficult to maintain, and
since I in the process of rewriting the recursive code, my rule
is that I will only resolve security issues with MaraDNS 1.0's
recursive resolver without getting paid.
If resolving a given domain with MaraDNS' code is an urgent
issue for you, please consider helping beta-test Deadwood, or
sponsoring MaraDNS:
http://www.maradns.org/products.html
45. MaraDNS 1.2 has issues with NXDOMAINS and case sensitivity.
There is a known bug in MaraDNS 1.2.12 where, should a client
ask for a non-existent record in all caps, MaraDNS 1.2.12 will
return a NXDOMAIN instead of a "not there" reply. This can cause
there to be problems delivering email to the host in question if
a mail transport agent asks for a name in all caps.
If this is an issue for your organization, please upgrade to a
newer version of MaraDNS; MaraDNS 1.4 does not have this bug. If
you want to see this bug fixed in MaraDNS 1.2, please help
sponsor MaraDNS.
46. Can MaraDNS offer protection from phishing and malicious sites?
Yes.
Here is a webpage that explains how its done:
http://www.malwaredomains.com/?p=288
Should that website be down, I have made a local mirror of the
Perl script here:
createmaradns-pl.txt
47. Does maradns support star (wildcard) records?
Yes.
MaraDNS supports both having stars at the beginning of records
and the end of records. For example, to have
anything.example.com. have the IP 10.1.2.3, add this line to the
zone file for example.com:
*.example.com. A 10.1.2.3
To have stars at the end of records, csv2_default_zonefile has
to be set. The mararc parameter bind_star_handling affects how
star records are handled. More information is in the mararc
man page.
48. I'm having problems using MaraDNS with some *NIX command line
applications like telnet.
Some *NIX command line networking applications, such as telnet
and ssh, try to do either a reverse DNS lookup (IP-to-host name
conversion) or an IPv6 lookup. This slows things down and
sometimes causes the applications to not work at all.
For people who do not need IPv6 lookups, add the following line
to one's mararc file to have MaraDNS respond to all IPv6 lookups
with a bogus "not found" reply:
reject_aaaa = 1
If knowing the hostname a given IP has isn't important, these
kinds of lookups can also be disabled:
reject_ptr = 1
49. My virus scanner reports that MaraDNS or Deadwood has a virus
This can be caused either by a poorly written anti-virus program
reporting a false positive, or because a virus on your system
has infected your copy of MaraDNS/Deadwood.
Please use GPG to verify that the file which your scanner
reports having a virus in has not been altered. In addition,
please scan the file with AVG (free for non-commercial use) to
verify your virus scanner has not reported a false positive.
If you have verified the GPG signature of the program and AVG
reports a virus, please let us know on the MaraDNS mailing list.
Otherwise, please use a better virus scanner and make sure there
are no viruses on your computer.
50. I can not subscribe to the MaraDNS mailing list
The procedure for subscribing to the mailing list is as follows:
* Send an email to list-request@maradns.org with "Subscribe"
as the subject
* You will get an email from list-request@maradns.org asking
you to confirm your subscription. This can be done by
replying to the message, or, more simply, by clicking on the
link in the message.
* Once you click on that link, click on the button marked
"subscribe to list list"
* You will now get a message stating 'Welcome to the "list"
mailing list'.
* This email will tell you how to post to the mailing list. I
suggest reading it.
If you get an email from list-request@maradns.org with the
subject "The results of your email commands", you did not
correctly send an email to list-request@maradns.org with the
subject "Subscribe".
If you do not get the email from list-request@maradns.org asking
you for a confirmation, ensure that this email is not in your
"spam" or "junk mail" folder. If you are unable to get these
emails at your email address, please get a gmail email account,
which can successfully subscribe to the MaraDNS mailing list.
51. How does MaraDNS respond to EDNS (RFC2671) packets?
MaraDNS 1.4 responds to EDNS packets by ignoring the OPT record
and acting as if it the packet did not have an OPT record.
Deadwood (the recursive resolver for Deadwood 2.0, available
in the deadwood-#.#.## directory of any 1.4 MaraDNS release), up
through Deadwood 2.9.02 responds to EDNS packets by discarding
the packet and not responding. This was changed in Deadwood
2.9.03: Deadwood, as per RFC2671 section 5.3, now responds to
EDNS queries by replying with the NOTIMPL ("not implemented")
error code instead of answering the query. This was changed
again in Deadwood 2.9.04: Deadwood now, like MaraDNS 1 (as well
as DJBdns), handles a EDNS packet as if the OPT record did not
exist.
MicroDNS (available in the tools/misc directory of any 1.4
MaraDNS release), as of MaraDNS 1.4.05, responds to EDNS queries
the same way Deadwood 2.9.03 did: By giving back "NOTIMPL"
instead of answering the query with the default IP. NanoDNS,
in the interest of minimizing code side, responds to EDNS
requests by returning NOTIMPL in the header, giving the OPT
query in the AN section of the response, and giving the default
IP in the AR section of the DNS reply packet.
52. How to I get MaraDNS to always give the same IP to all DNS
queries?
There are three ways to have MaraDNS always give the same IP in
reply to any DNS query given to it:
* The best way to do this is to set up a default zonefile
that causes any and all A queries to always give the IP (and
also allows all AAAA queries to always give out the same
IP6, all SPF or TXT queries to give out the same SPF record,
etc.).
* Another possibility, if someone just wants a simple DNS
server that always gives out the same IP address to any and
all DNS queries, is to use the MicroDNS program, available
in tools/misc, as well as having its own web page.
* If MicroDNS is too bloated, there is also NanoDNS, which
I will include the source code of below:
/*Placed in the public domain by Sam Trenholme*/
#include <arpa/inet.h>
#include <string.h>
#include <stdint.h>
#define Z struct sockaddr
#define Y sizeof(d)
int main(int a,char **b){uint32_t i;char q
,p="\xc0\f\0\x01\0\x01\0\0\0\0\0\x04";if(a>
1){struct sockaddr_in d;socklen_t f=511;bzero(&
d,Y);a=socket(AF_INET,SOCK_DGRAM,0);*((uint32_t
*)(p+12))=inet_addr(b);d.sin_family=AF_INET;
d.sin_port=htons(53);bind(a,(Z*)&d,Y);for(;;){i
=recvfrom(a,q,255,0,(Z*)&d,&f);if(i>9&&q>=0)
{q|=128;q?q|=4:1;q++;memcpy(q+i,p,
16);sendto(a,q,i+16,0,(Z*)&d,Y);}}}return 0;}
NanoDNS takes one argument: The IP we return. This program binds
to all IP addresses a given machine has on the UDP DNS port
(port 53). For example, to make a DNS server that binds to all
IPs your system has and return the IP 10.11.12.13 to any UDP DNS
queries sent to it, compile the above C program, call it
NanoDNS, and invoke it with NanoDNS 10.11.12.13 Note that
NanoDNS does not daemonize, nor log anything, nor have any other
space-wasting features.
BUGS
In the unusual case of having a csv2 zone file with
Macintosh-style newlines (as opposed to DOS or UNIX newlines),
while the file will parse, any errors in the file will be
reported as being on line 1.
The maximum allowed number of threads is 5000.
The system startup script included with MaraDNS assumes that the
only MaraDNS processes running are started by the script; it
stops all MaraDNS processes running on the server when asked to
stop MaraDNS.
When a resolver asks for an A record, and the A record is a
CNAME which points to a list of IPs, MaraDNS' recursive resolver
only returns the first IP listed along with the CNAME. This is
somewhat worked around by having a CNAME record only stay in the
recursive cache for 15 minutes.
When a resolver asks for an A record, and the A record is a
CNAME that points to another CNAME (and possibly a longer CNAME
chain), while MaraDNS returns the correct IP (as long as the
glueless level is not exceeded), MaraDNS will incorrectly state
that the first CNAME in the chain directly points to the IP.
If a NS record points to a list of IPs, and the NS record in
question is a "glueless" record (MaraDNS had to go back to the
root servers to find out the IP of the machine in question),
MaraDNS' recursive resolver only uses the first listed IP as a
name server.
When MaraDNS' recursive resolver receives a "host not there"
reply, instead of using the SOA minimum of the "host not there"
reply as the TTL (Look at RFC1034 §4.3.4), MaraDNS uses the TTL
of the SOA reply.
MaraDNS keeps referral NS records in the cache for one day
instead of the TTL specified by the remote server.
MaraDNS needs to use the zoneserver program to serve DNS records
over TCP. See zoneserver(8) for usage information.
MaraDNS does not use the zone file ("master file") format
specified in chapter 5 of RFC1035.
MaraDNS default behavior with star records is not RFC-compliant.
In more detail, if a wildcard MX record exists in the form
"*.example.com", and there is an A record for "www.example.com",
but no MX record for "www.example.com", the correct behavior
(based on RFC1034 §4.3.3) is to return "no host" (nothing in
the answer section, SOA in the authority section, 0 result code)
for a MX request to "www.example.com". Instead, MaraDNS returns
the MX record attached to "*.example.com". This can be changed
by setting bind_star_handling to 1.
Star records (what RFC1034 calls "wildcards") can not be
attached to NS records.
MaraDNS recursive resolver treats any TTL shorter than min_ttl
seconds (min_ttl_cname seconds when the record is a CNAME
record) as if the TTL in question was min_ttl (or min_ttl_cname)
seconds long when determining when to expire a record from
MaraDNS' cache.
TTLs which are shorter than 20 seconds long are given a TTL of
20 seconds; TTLs which are more than 63072000 (2 years) long are
given a TTL of 2 years.
MaraDNS' recursive resolver's method of deleting not recently
accessed records from the cache when the cache starts to fill up
can deleted records from the cache before they expire. Some
people consider this undesirable behavior; I feel it is
necessary behavior if one wishes to place a limit on the memory
resources a DNS server may use.
MaraDNS' recursive resolver stops resolving when it finds an
answer in the AR section. This is a problem in the case where a
given host name and IP is registered with the root name servers,
and the registered IP is out of date. When this happens, a
server "closer" to the root server will give an out-of-date IP,
even though the authoritative DNS servers for the host in
question have the correct IP. Note that resolving this will
result in increased DNS traffic.
MaraDNS, like every other known DNS implementation, only
supports a QDCOUNT of 0 or 1.
MaraDNS spawns a new thread for every single recursive DNS
request when the data in question is not in MaraDNS' cache; this
makes MaraDNS an excellent stress tester for pthread
implementations. Many pthread implementations can not handle
this kind of load; symptoms include high memory usage and
termination of the MaraDNS process.
MaraDNS does not handle the case of a glueless in-bailiwick NS
referral very gracefully; this usually causes the zone pointed
to by the offending NS record to be unreachable by MaraDNS, even
if other DNS servers for the domain have correct NS referrals.
UNIMPLEMENTED FEATURES
These are features which I do not plan to implement in MaraDNS.
If you wish to see these features, consider sponsoring MaraDNS
development:
MaraDNS does not have a disk-based caching scheme for
authoritative zones.
MaraDNS' UDP server only loads zone files while MaraDNS is first
started. UDP Zone information can only be updated by stopping
MaraDNS, and restarting MaraDNS again. Note that TCP zone files
are loaded from the filesystem at the time the client requests a
zone.
MaraDNS does not have support for allowing given host names to
only resolve for a limited range of IPs querying the DNS server,
or for host names to resolve differently, depending on the IP
querying the host name.
MaraDNS 1.4 only has authoritative-only support for IPv6.
Deadwood, however, has full IPv6 support.
MaraDNS only allows wildcards at the beginning or end of a host
name. E.g. names with wildcards like "foo.*.example.com".
"www.*" will work, however, if a default zonefile is set up.
MaraDNS does not have support for MRTG or any other SNMP-based
logging mechanism.
LEGAL DISCLAIMER
THIS SOFTWARE IS PROVIDED BY THE AUTHORS ''AS IS'' AND ANY
EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS
OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
THE POSSIBILITY OF SUCH DAMAGE.
AUTHORS
Sam Trenholme (http://www.samiam.org) is responsible for
this man page.
MaraDNS is written by me, Sam Trenholme, with a little help from
my friends. Naturally, all errors in MaraDNS are my own (but
read the disclaimer above).
Here is a partial list of people who have provided assistance:
Floh has generously set up a FreeBSD 4, FreeBSD 6, and Mac OS X
system so that I can port MaraDNS to more platforms.
Albert Lee has provided countless bug reports, and, nicely
enough, patches to fix said bugs. He has also made improvements
to the code in the tcp "zoneserver".
Franky Van Liedekerke has provided much invaluable assistance.
As just one example, he provided invaluable assistance in
getting MaraDNS to compile on Solaris. In addition, he has
provided much valuable SQA help.
Christian Kurz, who has provided invaluable bug reports,
especially when I had to re-implement the core hashing
algorithm.
Remmy, who is providing both the web space and a mailing list
for maradns.org.
Phil Homewood, who provided invaluable assistance with finding
and fixing bugs in the authoritative portion of the MaraDNS
server. He helped me plug memory leaks, find uninitialized
variables being used, and found a number of bugs I was unable to
find.
Albert Prats kindly provided Spanish translations for various
text files.
Shin Zukeran provided a patch to recursive.c which properly
makes a normal null-terminated string from a js_string object,
to send as an argument to open() so we can get the rijndael key
for the PRNG.
D Richard Felker III has provided invaluable bug reports. By
looking at his bug reports, I have been able to hunt down and
fix many problems that the recursive nameserver had, in addition
to at least one problem with the authoritative nameserver.
Ole Tange has also given me many valuable MaraDNS bug reports.
Florin Iucha provided a tip in the FAQ for how to compile
MaraDNS on OpenBSD.
Roy Arends (one of the BIND developers, as it turns out) found a
serious security problem with MaraDNS, where MaraDNS would
answer answers, and pointed it out to me.
Code used as the basis for the psudo-random-number generator was
written by Vincent Rijmen, Antoon Bosselaers, and Paulo Barreto.
I appreciate these programmers making the code public domain,
which is the only license under which I can add code to MaraDNS
under.
Ross Johnson and others have made a Win32 port of the Pthreads
library; this has made a native win32 port of MaraDNS possible.
I also appreciate the work of Dr. Brian Gladman and Fritz
Schneider, who have both written independent implementations of
AES from which I obtained test vectors. With the help of their
hard work, I was able to discover a subtle security problem that
previous releases of MaraDNS had.
distrib
>
Mageia
>
4
>
i586
>
media
>
core-release
>
by-pkgid
>
07a81589bb2c4aa5e88f35a4a345a184
>
files
>
302
