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# Alternative (more granular) approach to a DNS library

> Less is more.

Complete and usable DNS library. All widely used Resource Records are
supported, including the DNSSEC types. It follows a lean and mean philosophy.
If there is stuff you should know as a DNS programmer there isn't a convenience
function for it. Server side and client side programming is supported, i.e. you
can build servers and resolvers with it.

We try to keep the "master" branch as sane as possible and at the bleeding edge
of standards, avoiding breaking changes wherever reasonable. We support the last
two versions of Go, currently: 1.4 and 1.5.

# Goals

* KISS;
* Fast;
* Small API, if its easy to code in Go, don't make a function for it.

# Users

A not-so-up-to-date-list-that-may-be-actually-current:

* https://cloudflare.com
* https://github.com/abh/geodns
* http://www.statdns.com/
* http://www.dnsinspect.com/
* https://github.com/chuangbo/jianbing-dictionary-dns
* http://www.dns-lg.com/
* https://github.com/fcambus/rrda
* https://github.com/kenshinx/godns
* https://github.com/skynetservices/skydns
* https://github.com/hashicorp/consul
* https://github.com/DevelopersPL/godnsagent
* https://github.com/duedil-ltd/discodns
* https://github.com/StalkR/dns-reverse-proxy
* https://github.com/tianon/rawdns
* https://mesosphere.github.io/mesos-dns/
* https://pulse.turbobytes.com/
* https://play.google.com/store/apps/details?id=com.turbobytes.dig
* https://github.com/fcambus/statzone
* https://github.com/benschw/dns-clb-go
* https://github.com/corny/dnscheck for http://public-dns.info/
* https://namesmith.io
* https://github.com/miekg/unbound
* https://github.com/miekg/exdns
* https://dnslookup.org

Send pull request if you want to be listed here.

# Features

* UDP/TCP queries, IPv4 and IPv6;
* RFC 1035 zone file parsing ($INCLUDE, $ORIGIN, $TTL and $GENERATE (for all record types) are supported;
* Fast:
    * Reply speed around ~ 80K qps (faster hardware results in more qps);
    * Parsing RRs ~ 100K RR/s, that's 5M records in about 50 seconds;
* Server side programming (mimicking the net/http package);
* Client side programming;
* DNSSEC: signing, validating and key generation for DSA, RSA and ECDSA;
* EDNS0, NSID;
* AXFR/IXFR;
* TSIG, SIG(0);
* DNS over TLS: optional encrypted connection between client and server;
* DNS name compression;
* Depends only on the standard library.

Have fun!

Miek Gieben  -  2010-2012  -  <miek@miek.nl>

# Building

Building is done with the `go` tool. If you have setup your GOPATH
correctly, the following should work:

    go get github.com/miekg/dns
    go build github.com/miekg/dns

## Examples

A short "how to use the API" is at the beginning of doc.go (this also will show
when you call `godoc github.com/miekg/dns`).

Example programs can be found in the `github.com/miekg/exdns` repository.

## Supported RFCs

*all of them*

* 103{4,5} - DNS standard
* 1348 - NSAP record (removed the record)
* 1982 - Serial Arithmetic
* 1876 - LOC record
* 1995 - IXFR
* 1996 - DNS notify
* 2136 - DNS Update (dynamic updates)
* 2181 - RRset definition - there is no RRset type though, just []RR
* 2537 - RSAMD5 DNS keys
* 2065 - DNSSEC (updated in later RFCs)
* 2671 - EDNS record
* 2782 - SRV record
* 2845 - TSIG record
* 2915 - NAPTR record
* 2929 - DNS IANA Considerations
* 3110 - RSASHA1 DNS keys
* 3225 - DO bit (DNSSEC OK)
* 340{1,2,3} - NAPTR record
* 3445 - Limiting the scope of (DNS)KEY
* 3597 - Unknown RRs
* 4025 - IPSECKEY
* 403{3,4,5} - DNSSEC + validation functions
* 4255 - SSHFP record
* 4343 - Case insensitivity
* 4408 - SPF record
* 4509 - SHA256 Hash in DS
* 4592 - Wildcards in the DNS
* 4635 - HMAC SHA TSIG
* 4701 - DHCID
* 4892 - id.server
* 5001 - NSID
* 5155 - NSEC3 record
* 5205 - HIP record
* 5702 - SHA2 in the DNS
* 5936 - AXFR
* 5966 - TCP implementation recommendations
* 6605 - ECDSA
* 6725 - IANA Registry Update
* 6742 - ILNP DNS
* 6840 - Clarifications and Implementation Notes for DNS Security
* 6844 - CAA record
* 6891 - EDNS0 update
* 6895 - DNS IANA considerations
* 6975 - Algorithm Understanding in DNSSEC
* 7043 - EUI48/EUI64 records
* 7314 - DNS (EDNS) EXPIRE Option
* 7553 - URI record
* xxxx - EDNS0 DNS Update Lease (draft)
* yyyy - DNS over TLS: Initiation and Performance Considerations (draft)

## Loosely based upon

* `ldns`
* `NSD`
* `Net::DNS`
* `GRONG`

## TODO

* privatekey.Precompute() when signing?
* Last remaining RRs: APL, ATMA, A6, NSAP and NXT.
* Missing in parsing: ISDN, UNSPEC, NSAP and ATMA.
* NSEC(3) cover/match/closest enclose.
* Replies with TC bit are not parsed to the end.
