This Python module acts as a DNS tap streams receiver for DNS servers. Input streams can be a unix socket or multiple remote dns servers. The output is printed directly to stdout or send to remote tcp address in JSON, YAML or one line text format and more.
Deploy the dnstap receiver in your DNS server with the pip command.
pip install dnstap_receiver
After installation, you can execute the dnstap_receiver
to start-it.
Usage:
usage: dnstap_receiver [-h] [-l L] [-p P] [-u U] [-v] [-c C]
optional arguments:
-h, --help show this help message and exit
-l L IP of the dnsptap server to receive dnstap payloads (default: '0.0.0.0')
-p P Port the dnstap receiver is listening on (default: 6000)
-u U read dnstap payloads from unix socket
-v verbose mode
-c C external config file
Pull the dnstap receiver image from Docker Hub.
docker pull dmachard/dnstap-receiver:latest
Deploy the container
docker run -d -p 6000:6000 --name=dnstap01 dmachard/dnstap-receiver
Follow containers logs
docker logs dnstap01 -f
Severals inputs handler are supported to read incoming dnstap messages:
The TCP socket input enable to receive dnstap messages from multiple dns servers.
This is the default input if you execute the binary without arguments.
The receiver is listening on localhost
interface and the tcp port 6000
.
You can change binding options with -l
and -p
arguments.
./dnstap_receiver -l 0.0.0.0 -p 6000
You can also activate TLS
on the socket, add the following config as external config file
to activate the tls support, configure the path of the certificate and key to use.
input:
tcp-socket:
# enable tls support
tls-support: true
# provide certificate server path
tls-server-cert: /etc/dnstap_receiver/server.crt
# provide certificate key path
tls-server-key: /etc/dnstap_receiver/server.key
Then execute the dnstap receiver with the configuration file:
./dnstap_receiver -c /etc/dnstap-receiver/dnstap.conf
The unix socket input enables read dnstap message from a unix socket.
Configure the path of the socket with the -u
argument.
./dnstap_receiver -u /var/run/dnstap.sock
Outputs handler can be configured to forward messages in several modes.
This output enables to forward dnstap messages directly to Stdout. Add the following configuration as external config to activate this output:
output:
stdout:
# enable or disable
enable: true
# format available text|json|yaml
format: text
Output can be formatted in different way:
- text (default one)
- json
- yaml
Text format:
2020-09-16T18:51:53.547352+00:00 centos RESOLVER_QUERY NOERROR - - IP4 UDP 43b ns2.google.com. A
2020-09-16T18:51:53.591736+00:00 centos RESOLVER_RESPONSE NOERROR - - IP4 UDP 59b ns2.google.com. A
JSON format:
{
"identity": "dev-centos8",
"query-name": "www.google.com.",
"query-type": "A",
"source-ip": "192.168.1.114",
"message": "CLIENT_QUERY",
"protocol": "IP4",
"transport": "UDP",
"source-port": 42222,
"length": 43,
"timestamp": "2020-09-16T18:51:53.591736+00:00",
"code": "NOERROR"
}
YAML format:
code: NOERROR
length: 49
message: RESOLVER_QUERY
protocol: IP4
query-name: dns4.comlaude-dns.eu.
query-type: AAAA
source-ip: '-'
source-port: '-'
timestamp: '2020-09-16T18:51:53.591736+00:00'
transport: UDP
This output enables to forward dnstap message to a remote tcp collector. Add the following configuration as external config to activate this output:
output:
# forward to remote tcp destination
tcp-socket:
# enable or disable
enable: true
# format available text|json|yaml
format: text
# delimiter
delimiter: "\n"
# retry interval in seconds to connect
retry: 5
# remote ipv4 or ipv6 address
remote-address: 10.0.0.2
# remote tcp port
remote-port: 8192
This output enables to forward dnstap message to a syslog server. Add the following configuration as external config to activate this output:
output:
syslog:
# enable or disable
enable: false
# syslog over tcp or udp
transport: udp
# format available text|json
format: text
# retry interval in seconds to connect
retry: 5
# remote ipv4 or ipv6 address of the syslog server
remote-address: 10.0.0.2
# remote port of the syslog server
remote-port: 514
Example of output on syslog server
Sep 22 12:43:01 bind CLIENT_RESPONSE NOERROR 192.168.1.100 51717 IP4 UDP 173b www.netflix.fr. A
Sep 22 12:43:01 bind CLIENT_RESPONSE NOERROR 192.168.1.100 51718 IP4 UDP 203b www.netflix.fr. AAAA
This output enables to generate metrics in one line and print-it to stdout. Add the following configuration as external config to activate this output:
output:
metrics:
# enable or disable
enable: true
# print every N seconds.
interval: 300
# cumulative statistics, without clearing them after printing
cumulative: false
Example of output
2020-10-13 05:19:35,522 18 QUERIES, 3.6 QPS, 1 CLIENTS, 18 IP4, 0 IP6,
18 UDP, 0 TCP, 17 NOERROR, 1 NXDOMAIN, 18 A, 0 AAAA
The dnstap_receiver
binary can takes an external config file with the -c
argument
See config file example.
./dnstap_receiver -c /etc/dnstap-receiver/dnstap.conf
You can execute the binary in verbose mode with the -v
argument:
./dnstap_receiver -v
2020-09-12 23:47:35,833 Start dnstap receiver...
2020-09-12 23:47:35,833 Using selector: EpollSelector
2020-09-12 23:47:35,834 Listening on 0.0.0.0:6000
This feature can be useful if you want to ignore some messages and keep just what you want. Several filter are available:
- by qname field
- by dnstap identity field.
You can filtering incoming dnstap messages according to the dnstap identity field. A regex can be configured in the external configuration file to do that
filter:
# dnstap identify filtering feature with regex support
dnstap-identities: dnsdist01|unbound01
You can filtering incoming dnstap messages according to the query name. A regex can be configured in the external configuration file to do that
filter:
# qname filtering feature with regex support
qname-regex: ".*.com"
This dnstap receiver has been tested with success with the following dns servers:
- ISC - bind
- PowerDNS - dnsdist, pdns-recursor
- NLnet Labs - nsd, unbound
Dnstap messages supported:
- RESOLVER_QUERY
- RESOLVER_RESPONSE
- CLIENT_QUERY
- CLIENT_RESPONSE
- AUTH_QUERY
- AUTH_RESPONSE
Download latest source and build-it with dnstap support:
./configure --enable-dnstap
make && make install
Update the configuration file /etc/named.conf
to activate the dnstap feature:
options {
dnstap { client; auth; resolver; forwarder; };
dnstap-output unix "/var/run/named/dnstap.sock";
dnstap-identity "dns-bind";
dnstap-version "bind";
}
Execute the dnstap receiver with named
user:
su - named -s /bin/bash -c "dnstap_receiver -u "/var/run/named/dnstap.sock""
Dnstap messages supported:
- RESOLVER_QUERY
- RESOLVER_RESPONSE
Update the configuration file to activate the dnstap feature:
vim /etc/pdns-recursor/recursor.conf
lua-config-file=/etc/pdns-recursor/recursor.lua
vim /etc/pdns-recursor/recursor.lua
dnstapFrameStreamServer("/var/run/pdns-recursor/dnstap.sock")
Execute the dnstap receiver with pdns-recursor
user:
su - pdns-recursor -s /bin/bash -c "dnstap_receiver -u "/var/run/pdns-recursor/dnstap.sock""
Update the configuration file to activate the dnstap feature with tcp mode and execute the dnstap receiver in listening tcp socket mode:
vim /etc/pdns-recursor/recursor.conf
lua-config-file=/etc/pdns-recursor/recursor.lua
vim /etc/pdns-recursor/recursor.lua
dnstapFrameStreamServer("10.0.0.100:6000")
Dnstap messages supported:
- CLIENT_QUERY
- CLIENT_RESPONSE
Create the dnsdist folder where the unix socket will be created:
mkdir -p /var/run/dnsdist/
chown dnsdist.dnsdist /var/run/dnsdist/
Update the configuration file /etc/dnsdist/dnsdist.conf
to activate the dnstap feature:
fsul = newFrameStreamUnixLogger("/var/run/dnsdist/dnstap.sock")
addAction(AllRule(), DnstapLogAction("dnsdist", fsul))
addResponseAction(AllRule(), DnstapLogResponseAction("dnsdist", fsul))
Execute the dnstap receiver with dnsdist
user:
su - dnsdist -s /bin/bash -c "dnstap_receiver -u "/var/run/dnsdist/dnstap.sock""
Update the configuration file /etc/dnsdist/dnsdist.conf
to activate the dnstap feature
with tcp stream and execute the dnstap receiver in listening tcp socket mode:
fsul = newFrameStreamTcpLogger("127.0.0.1:8888")
addAction(AllRule(), DnstapLogAction("dnsdist", fsul))
addResponseAction(AllRule(), DnstapLogResponseAction("dnsdist", fsul))
Dnstap messages supported:
- AUTH_QUERY
- AUTH_RESPONSE
Download latest source and build-it with dnstap support:
./configure --enable-dnstap
make && make install
Update the configuration file /etc/nsd/nsd.conf
to activate the dnstap feature:
dnstap:
dnstap-enable: yes
dnstap-socket-path: "/var/run/nsd/dnstap.sock"
dnstap-send-identity: yes
dnstap-send-version: yes
dnstap-log-auth-query-messages: yes
dnstap-log-auth-response-messages: yes
Execute the dnstap receiver with nsd
user:
su - nsd -s /bin/bash -c "dnstap_receiver -u "/var/run/nsd/dnstap.sock""
Dnstap messages supported:
- CLIENT_QUERY
- CLIENT_RESPONSE
- RESOLVER_QUERY
- RESOLVER_RESPONSE
- CLIENT_QUERY
- CLIENT_RESPONSE
Download latest source and build-it with dnstap support:
./configure --enable-dnstap
make && make install
Update the configuration file /etc/unbound/unbound.conf
to activate the dnstap feature:
dnstap:
dnstap-enable: yes
dnstap-socket-path: "dnstap.sock"
dnstap-send-identity: yes
dnstap-send-version: yes
dnstap-log-resolver-query-messages: yes
dnstap-log-resolver-response-messages: yes
dnstap-log-client-query-messages: yes
dnstap-log-client-response-messages: yes
dnstap-log-forwarder-query-messages: yes
dnstap-log-forwarder-response-messages: yes
Execute the dnstap receiver with unbound
user:
su - unbound -s /bin/bash -c "dnstap_receiver -u "/usr/local/etc/unbound/dnstap.sock""
Update the configuration file /etc/unbound/unbound.conf
to activate the dnstap feature
with tcp mode and execute the dnstap receiver in listening tcp socket mode:
dnstap:
dnstap-enable: yes
dnstap-socket-path: ""
dnstap-ip: "10.0.0.100@6000"
dnstap-tls: no
dnstap-send-identity: yes
dnstap-send-version: yes
dnstap-log-client-query-messages: yes
dnstap-log-client-response-messages: yes
Update the configuration file /etc/unbound/unbound.conf
to activate the dnstap feature
with tls mode and execute the dnstap receiver in listening tcp/tls socket mode:
dnstap:
dnstap-enable: yes
dnstap-socket-path: ""
dnstap-ip: "10.0.0.100@6000"
dnstap-tls: yes
dnstap-send-identity: yes
dnstap-send-version: yes
dnstap-log-client-query-messages: yes
dnstap-log-client-response-messages: yes
Author | Denis Machard d.machard@gmail.com |
PyPI | https://pypi.org/project/dnstap_receiver/ |
Github | https://github.com/dmachard/dnstap-receiver |
DockerHub | https://hub.docker.com/r/dmachard/dnstap-receiver |