MassDNS 0.3
A high-performance DNS stub resolver
MassDNS is a simple high-performance DNS stub resolver targetting those who seek to resolve a massive amount of domain names in the order of millions or even billions. Without special configuration, MassDNS is capable of resolving over 350,000 names per second using publicly available resolvers.
Installation
git clone https://github.com/blechschmidt/massdns.git
cd massdns
make
Usage
./bin/massdns [options] [domainlist]
-b --bindto Bind to IP address and port. (Default: 0.0.0.0:0)
-c --resolve-count Number of resolves for a name before giving up. (Default: 50)
--drop-user User to drop privileges to when running as root. (Default: nobody)
--flush Flush the output file whenever a response was received.
-h --help Show this help.
-i --interval Interval in milliseconds to wait between multiple resolves of the same
domain. (Default: 500)
-l --error-log Error log file path. (Default: /dev/stderr)
--norecurse Use non-recursive queries. Useful for DNS cache snooping.
-o --output Flags for output formatting.
--predictable Use resolvers incrementally. Useful for resolver tests.
--processes Number of processes to be used for resolving. (Default: 1)
-q --quiet Quiet mode.
--rcvbuf Size of the receive buffer in bytes.
--retry Unacceptable DNS response codes. (Default: REFUSED)
-r --resolvers Text file containing DNS resolvers.
--root Do not drop privileges when running as root. Not recommended.
-s --hashmap-size Number of concurrent lookups. (Default: 10000)
--sndbuf Size of the send buffer in bytes.
--sticky Do not switch the resolver when retrying.
--socket-count Socket count per process. (Default: 1)
-t --type Record type to be resolved. (Default: A)
--verify-ip Verify IP addresses of incoming replies.
-w --outfile Write to the specified output file instead of standard output.
Output flags:
S - simple text output
F - full text output
B - binary output
Example
Resolve all AAAA records from domains within domains.txt using the resolvers within resolvers.txt in lists and store the results within results.txt:
$ ./bin/massdns -r lists/resolvers.txt -t AAAA domains.txt > results.txt
This is equivalent to:
$ ./bin/massdns -r lists/resolvers.txt -t AAAA -w results.txt domains.txt
Example output
By default, MassDNS will output response packets in text format which looks similar to the following:
;; Server: 77.41.229.2:53
;; Size: 93
;; Unix time: 1513458347
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 51298
;; flags: qr rd ra ; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 0
;; QUESTION SECTION:
example.com. IN A
;; ANSWER SECTION:
example.com. 45929 IN A 93.184.216.34
;; AUTHORITY SECTION:
example.com. 24852 IN NS b.iana-servers.net.
example.com. 24852 IN NS a.iana-servers.net.
The resolver IP address is included in order to make it easier for you to filter the output in case you detect that some resolvers produce bad results.
Resolving
The repository includes the file resolvers.txt consisting of a filtered subset of the resolvers provided by the subbrute project. Please note that the usage of MassDNS may cause a significant load on the used resolvers and result in abuse complaints being sent to your ISP. Also note that the provided resolvers are not guaranteed to be trustworthy. The resolver list is currently outdated with a large share of resolvers being dysfunctional.
MassDNS’s DNS implementation is currently very sporadic and only supports the most common records. You are welcome to help to change this by collaborating.
Copyright (C) 2018 blechschmidt
Source: https://github.com/blechschmidt/
