dnsviz: A Python repository from nrshrivatsan

Description

DNSViz is a tool suite for analysis and visualization of Domain Name System (DNS) behavior, including its security extensions (DNSSEC). This tool suite powers the Web-based analysis available at http://dnsviz.net/

Installation

Dependencies

python (2.6/2.7/3.4) - http://www.python.org/

python 2.6, 2.7, or 3.4 is required. For python 3.4 the other third-party dependencies must also support python 3.4. Note that for python 2.6 the importlib (https://pypi.python.org/pypi/importlib) and ordereddict (https://pypi.python.org/pypi/ordereddict) packages are also required.
dnspython (1.11.0 or later) - http://www.dnspython.org/

dnspython is required. Version 1.10.0 is sufficient if you're not issuing TLSA queries, but more generally version 1.11.0 or greater is required.
pygraphviz (1.1 or later) - http://pygraphviz.github.io/

pygraphviz is required for most functionality. dnsviz probe and dnsviz grok (without the -t option) can be used without pygraphviz installed. Version 1.1 or greater is required because of the support for unicode names and HTML-like labels, both of which are utilized in the visual output.
M2Crypto (0.24.0 or later) - https://gitlab.com/m2crypto/m2crypto

M2Crypto is required if cryptographic validation of signatures and digests is desired (and thus is highly recommended). The current code will display warnings if the cryptographic elements cannot be verified.

Note that M2Crypto version 0.21.1 or later can be used to validate some DNSSEC algorithms, but support for the following DNSSEC algorithms is not available in releases of M2Crypto prior to 0.24.0 without a patch: 3 (DSA-SHA1), 6 (DSA-NSEC3-SHA1), 12 (GOST R 34.10-2001), 13 (ECDSA Curve P-256 with SHA-256), 14 (ECDSA Curve P-384 with SHA-384). There are two patches included in the contrib directory that can be applied to pre-0.24.0 versions to get this functionality: contrib/m2crypto-pre0.23.patch or contrib/m2crypto-0.23.patch. For example:
```
$ patch -p1 < /path/to/dnsviz-source/contrib/m2crypto-pre0.23.patch
```
(optional) libnacl - https://github.com/saltstack/libnacl

libnacl is necessary to validate DNSSEC signatures with algorithm 15 (Ed25519).
(optional) ISC BIND - https://www.isc.org/downloads/bind/

When calling dnsviz probe if the -N option is used or if a zone file is used in conjunction with the -x option, named(8) is looked for in PATH and invoked to serve the zone file. ISC BIND is only needed in this specific case, and named(8) does not need to be running.

Generic Build and Install

A generic build and install is performed with the following commands:

$ python setup.py build
$ sudo python setup.py install

To see all installation options, run the following:

$ python setup.py --help

RPM Build and Install (RHEL6 or RHEL7)

Install pygraphviz and M2Crypto, after installing their build dependencies.

$ sudo yum install python-setuptools gcc python-devel graphviz-devel openssl-devel
$ sudo easy_install pbr
$ sudo easy_install m2crypto pygraphviz

(RHEL6 only) Install the EPEL repository, and the necessary python libraries from that repository.

$ sudo yum install epel-release
$ sudo yum install python-importlib python-ordereddict

Install dnspython.

$ sudo yum install python-dns

Install rpm-build tools, then build and install the DNSViz RPM.

$ sudo yum install rpm-build
$ python setup.py bdist_rpm --install-script contrib/rpm-install.sh --distribution-name el${RHEL_VERS}
$ sudo rpm -iv dist/dnsviz-*-1.noarch.rpm

Note that a custom install script is used to properly install the DNSViz man pages. The value of ${RHEL_VERS} corresponds to the RHEL version (e.g., 6 or 7).

Usage

DNSViz is invoked using the dnsviz command-line utility. dnsviz itself uses several subcommands: probe, grok, graph, print, and query. See the man pages associated with each subcommand, in the form of "dnsviz- (1)" (e.g., "man dnsviz-probe") for more detailed documentation and usage.

dnsviz probe

dnsviz probe takes one or more domain names as input and performs a series of queries to either recursive (default) or authoritative DNS servers, the results of which are serialized into JSON format.

Examples

Analyze the domain name example.com using your configured DNS resolvers (i.e., in /etc/resolv.conf) and store the queries and responses in the file named "example.com.json":

$ dnsviz probe example.com > example.com.json

Same thing:

$ dnsviz probe -o example.com.json example.com

Analyze the domain name example.com by querying its authoritative servers directly:

$ dnsviz probe -A -o example.com.json example.com

Analyze the domain name example.com by querying explicitly-defined authoritative servers, rather than learning the servers through referrals from the IANA root servers:

$ dnsviz probe -A \
  -x example.com:a.iana-servers.org=199.43.132.53,a.iana-servers.org=[2001:500:8c::53] \
  -x example.com:b.iana-servers.org=199.43.133.53,b.iana-servers.org=[2001:500:8d::53] \
  -o example.com.json example.com

Same, but have dnsviz probe resolve the names:

$ dnsviz probe -A \
  -x example.com:a.iana-servers.org,b.iana-servers.org \
  -o example.com.json example.com

Analyze the domain name example.com and its entire ancestry by querying authoritative servers and following delegations, starting at the root:

$ dnsviz probe -A -a . -o example.com.json example.com

Analyze multiple names in parallel (four threads) using explicit recursive resolvers (replace 192.0.1.2 and 2001:db8::1 with legitimate resolver addresses):

$ dnsviz probe -s 192.0.2.1,[2001:db8::1] -t 4 -o multiple.json \
  example.com sandia.gov verisignlabs.com dnsviz.net

dnsviz grok

dnsviz grok takes serialized query results in JSON format (i.e., output from dnsviz probe) as input and assesses specified domain names based on their corresponding content in the input. The output is also serialized into JSON format.

Examples

Process the query/response output produced by dnsviz probe, and store the serialized results in a file named "example.com-chk.json":

$ dnsviz grok < example.com.json > example.com-chk.json

Same thing:

$ dnsviz grok -r example.com.json -o example.com-chk.json example.com

Show only info-level information: descriptions, statuses, warnings, and errors:

$ dnsviz grok -l info -r example.com.json -o example.com-chk.json

Show descriptions only if there are related warnings or errors:

$ dnsviz grok -l warning -r example.com.json -o example.com-chk.json

Show descriptions only if there are related errors:

$ dnsviz grok -l error -r example.com.json -o example.com-chk.json

Use root key as DNSSEC trust anchor, to additionally indicate authentication status of responses:

$ dig +noall +answer . dnskey | awk '$5 % 2 { print $0 }' > tk.txt
$ dnsviz grok -l info -t tk.txt -r example.com.json -o example.com-chk.json

Pipe dnsviz probe output directly to dnsviz grok:

$ dnsviz probe example.com | \
      dnsviz grok -l info -o example.com-chk.json

Same thing, but save the raw output (for re-use) along the way:

$ dnsviz probe example.com | tee example.com.json | \
      dnsviz grok -l info -o example.com-chk.json

Assess multiple names at once with error level:

$ dnsviz grok -l error -r multiple.json -o example.com-chk.json

dnsviz graph

dnsviz graph takes serialized query results in JSON format (i.e., output from dnsviz probe) as input and assesses specified domain names based on their corresponding content in the input. The output is an image file, a dot (directed graph) file, or an HTML file, depending on the options passed.

Examples

Process the query/response output produced by dnsviz probe, and produce a graph visually representing the results in a png file named "example.com.png".

$ dnsviz graph -Tpng < example.com.json > example.com.png

Same thing:

$ dnsviz graph -Tpng -o example.com.png example.com < example.com.json

Same thing, but produce interactive HTML format: interactive HTML output in a file named "example.com.html":

$ dnsviz graph -Thtml < example.com.json > example.com.html

Same thing (filename is derived from domain name and output format):

$ dnsviz graph -Thtml -O -r example.com.json

Use alternate DNSSEC trust anchor:

$ dig +noall +answer example.com dnskey | awk '$5 % 2 { print $0 }' > tk.txt
$ dnsviz graph -Thtml -O -r example.com.json -t tk.txt

Pipe dnsviz probe output directly to dnsviz graph:

$ dnsviz probe example.com | \
      dnsviz graph -Thtml -O

Same thing, but save the raw output (for re-use) along the way:

$ dnsviz probe example.com | tee example.com.json | \
      dnsviz graph -Thtml -O

Process analysis of multiple domain names, creating an image for each name processed:

$ dnsviz graph -Thtml -O -r multiple.json

Process analysis of multiple domain names, creating a single image for all names.

$ dnsviz graph -Thtml -r multiple.json > multiple.html

dnsviz print

dnsviz print takes serialized query results in JSON format (i.e., output from dnsviz probe) as input and assesses specified domain names based on their corresponding content in the input. The output is textual output suitable for file or terminal display.

Examples

Process the query/response output produced by dnsviz probe, and output the results to the terminal:

$ dnsviz print < example.com.json

Use alternate DNSSEC trust anchor:

$ dig +noall +answer example.com dnskey | awk '$5 % 2 { print $0 }' > tk.txt
$ dnsviz print -r example.com.json -t tk.txt

Pipe dnsviz probe output directly to dnsviz print:

$ dnsviz probe example.com | \
      dnsviz print

Same thing, but save the raw output (for re-use) along the way:

$ dnsviz probe example.com | tee example.com.json | \
      dnsviz print

dnsviz query

dnsviz query is a wrapper that couples the functionality of dnsviz probe and dnsviz print into a tool with minimal dig-like usage, used to make analysis queries and return the textual output to terminal or file output in one go.

Examples

Analyze the domain name example.com using the first of your configured DNS resolvers (i.e., in /etc/resolv.conf):

$ dnsviz query example.com

Same, but specify an alternate trust anchor:

$ dnsviz query +trusted-key=tk.txt example.com

Analyze example.com through the recursive resolver at 192.0.2.1:

$ dnsviz query @192.0.2.1 +trusted-key=tk.txt example.com

Pre-Deployment DNS Testing

The examples in this section demonstrate usage of DNSViz for pre-deployment testing.

Pre-Delegation Testing

The following examples involve issuing diagnostic queries for a zone before it is ever delegated.

Issue queries against a zone file on the local system (example.com.zone). named(8) is invoked to serve the file locally:

$ dnsviz probe -A -x example.com+:example.com.zone example.com

(Note the use of "+", which designates that the parent servers should not be queried for DS records.)

Issue queries to a server that is serving the zone:

$ dnsviz probe -A -x example.com+:192.0.2.1 example.com

(Note that this server doesn't need to be a server in the NS RRset for example.com.)

Issue queries to the servers in the authoritative NS RRset, specified by name and/or address:

$ dnsviz probe -A \
      -x example.com+:ns1.example.com=192.0.2.1 \
      -x example.com+:ns2.example.com=192.0.2.1,ns2.example.com=[2001:db8::1] \
      example.com

Specify the names and addresses corresponding to the future delegation NS records and (as appropriate) A/AAAA glue records in the parent zone (com):

$ dnsviz probe -A \
      -N example.com:ns1.example.com=192.0.2.1 \
      -N example.com:ns2.example.com=192.0.2.1,ns2.example.com=[2001:db8::1] \
      example.com

Also supply future DS records:

$ dnsviz probe -A \
      -N example.com:ns1.example.com=192.0.2.1 \
      -N example.com:ns2.example.com=192.0.2.1,ns2.example.com=[2001:db8::1] \
      -D example.com:dsset-example.com. \
      example.com

Pre-Deployment Testing of Authoritative Zone Changes

The following examples involve issuing diagnostic queries for a delegated zone before changes are deployed.

Issue diagnostic queries for a new zone file that has been created but not yet been deployed (i.e., with changes to DNSKEY or other records):

$ dnsviz probe -A -x example.com:example.com.zone example.com

(Note the absence of "+", which designates that the parent servers will be queried for DS records.)

Issue queries to a server that is serving the new version of the zone:

$ dnsviz probe -A -x example.com:192.0.2.1 example.com

(Note that this server doesn't need to be a server in the NS RRset for example.com.)

Pre-Deployment Testing of Delegation Changes

The following examples involve issuing diagnostic queries for a delegated zone before changes are deployed to the delegation, glue, or DS records for that zone.

Specify the names and addresses corresponding to the new delegation NS records and (as appropriate) A/AAAA glue records in the parent zone (com):

$ dnsviz probe -A \
      -N example.com:ns1.example.com=192.0.2.1 \
      -N example.com:ns2.example.com=192.0.2.1,ns2.example.com=[2001:db8::1] \
      example.com

Also supply the replacement DS records:

$ dnsviz probe -A \
      -N example.com:ns1.example.com=192.0.2.1 \
      -N example.com:ns2.example.com=192.0.2.1,ns2.example.com=[2001:db8::1] \
      -D example.com:dsset-example.com. \
      example.com

nrshrivatsan/dnsviz

Description

Installation

Dependencies

Generic Build and Install

RPM Build and Install (RHEL6 or RHEL7)

Usage

dnsviz probe

Examples

dnsviz grok

Examples

dnsviz graph

Examples

dnsviz print

Examples

dnsviz query

Examples

Pre-Deployment DNS Testing

Pre-Delegation Testing

Pre-Deployment Testing of Authoritative Zone Changes

Pre-Deployment Testing of Delegation Changes