dndns Work Item Rss Feed

Commented Issue: Error in SrvRecord class

jmonty — Mon, 24 Nov 2008 18:41:50 GMT

Change the line:

_port = (ushort)IPAddress.NetworkToHostOrder(BitConverter.ToUInt16(port, 0));

to:

_port = (ushort)IPAddress.NetworkToHostOrder((short)BitConverter.ToUInt16(port, 0));

otherwise the returned port is always 0.

Stefano
Comments: ** Comment from web user: jmonty **

Fixed SrvRecord and AfsdbRecord cast issue in ChangeSet #18865.

Closed Issue: Error in SrvRecord class

jmonty — Mon, 24 Nov 2008 18:33:32 GMT

Closed Issue: Bug in Message Decompression

jmonty — Mon, 24 Nov 2008 18:30:46 GMT

The Message Compression pointer is notated by the two most significant bits set to one in first 2 bytes of the . e.g. 11000000 00000000. The remaining 14 bits contain the offset. DnDns has a bug calculating the offset position.

For example, 11000000 00001100 (0xc0 0x0c), indicates a pointer to location 1100 (0x0c). So any offset contained in the first byte is ignored, so 11000001 00011100 (0xc1 0x1c) was interpreted as 11000000 00011100 (0xc0 0x1c) and the DnDns will crash.

Created Issue: Bug in Message Decompression

jmonty — Mon, 24 Nov 2008 18:29:25 GMT

Commented Issue: Error in SrvRecord class

jmonty — Mon, 24 Nov 2008 15:00:26 GMT

Good catch! I've found several other instances that were missing the CAST.

Closed Issue: UDP Timeout concerns

jmonty — Mon, 24 Nov 2008 14:21:26 GMT

I appreciate the work you put into this. We were just talking about implementing something like this in-house. You saved us some time! I had one issue come up while using it though. I had a situation where a DNS server didn't exist or wasn't properly set, so the UDP Receive function would hang indefinitely. I changed your code to take in a timeout_ms parameter in the Resolve function, and I set the underlying socket receive timeout to use it so everything could dispose properly when it timed out. Works like a charm now! Thanks!

Here's a snippet

UdpClient udpClient = new UdpClient();
try
{
udpClient.Connect(ipep);
udpClient.Send(bDnsQuery, bDnsQuery.Length);

udpClient.Client.ReceiveTimeout = timeout_ms; //added socket timeout here.
recvBytes = udpClient.Receive(ref ipep);

}
finally
{
udpClient.Close();
}
Comments: Fixed in changeset 18841.

Commented Issue: UDP Timeout concerns

jmonty — Mon, 24 Nov 2008 14:21:02 GMT

Get changeset #18841 to get the Socket Timeout fix.

Commented Issue: UDP Timeout concerns

mman — Thu, 07 Aug 2008 15:37:13 GMT

I got the same problem with infinite timeout when server is not responding. I use downloaded library. Should I get source code and recompile with above patch or there will be a new precompiled version of library?

CREATED ISSUE: Error in SrvRecord class

jmonty — Thu, 29 May 2008 16:38:28 GMT

CREATED ISSUE: UDP Timeout concerns

jmonty — Sun, 06 Apr 2008 01:27:27 GMT

CREATED FEATURE: Add Support for Dynamic Updates (DNS UPDATE)

jmonty — Thu, 13 Mar 2008 20:30:09 GMT

DNS servers allow clients to dynamically update their DNS records when their IP address changes (for instance, useful when a client receives a new IP Addresses from a DHCP server).

References:
RFC 2136: Dynamic Updates in the Domain Name System (DNS UPDATE)
http://www.ietf.org/rfc/rfc2136.txt

RFC 2137: Secure Dynamic Updates in the Domain Name System (DNS UPDATE)

RFC 3007: Secure Domain Name System (DNS) Dynamic Update
http://www.ietf.org/rfc/rfc3007.txt

CREATED FEATURE: Add Support for Zone Transfers (AXFR)

jmonty — Tue, 11 Mar 2008 13:58:34 GMT

NOTE: "Because accuracy is essential, TCP or some other reliable protocol must be used for AXFR requests.", RFC 1024

References:
RFC 1034 - DOMAIN NAMES - CONCEPTS AND FACILITIES
http://www.ietf.org/rfc/rfc1034.txt

RFC 1996 - A Mechanism for Prompt Notification of Zone Changes (DNS NOTIFY)
http://www.ietf.org/rfc/rfc1996.txt

Notes on Implementing AXFR Zone Transfers (from DJB)
See: http://cr.yp.to/djbdns/axfr-notes.html

Also explore IXFR, RFC 1995 - Incremental Zone Transfer in DNS
http://www.ietf.org/rfc/rfc1995.txt

CREATED ISSUE: Add IPv6 Network Support

jmonty — Tue, 05 Feb 2008 15:11:59 GMT

Currently only IPv4 is used to query DNS Servers. As IPv6 become more prevalent, DnDns needs to support IPv6 networks as well.

CREATED ISSUE: Add IPv6 Specific DNS Record Support

jmonty — Tue, 05 Feb 2008 15:02:21 GMT

RFC 2874 introduces IPv6 Record Types to the DNS system. Add additional record type A6 and modify the following existing record types to support IPv6 specifics as well.

ref: http://www.ietf.org/rfc/rfc2874.txt

CREATED FEATURE: Create full client sample based on DnDns Library

jmonty — Sat, 02 Feb 2008 05:38:50 GMT

Tool would be similar to nslookup, perhaps more verbose.

CREATED ISSUE: Add Unit Tests

jmonty — Sat, 02 Feb 2008 05:32:55 GMT

This project started long before I knew or understood what test driven development or unit testing was. Ideally I'd like to add unit testing to the project to make additions/patching, etc. for this project a bit easier to maintain.

CREATED ISSUE: Add support for newer DNS Security Features (DNSSEC)

jmonty — Sat, 02 Feb 2008 05:32:02 GMT

"DNSSEC was designed to protect the Internet from certain attacks, such as DNS cache poisoning [0]. It is a set of extensions to DNS, which provide: a) origin authentication of DNS data, b) data integrity, and c) authenticated denial of existence."

Reference: http://www.dnssec.net/

CREATED FEATURE: Add Support for DNS Queries using the TCP protocol

jmonty — Sat, 02 Feb 2008 05:31:05 GMT

Infrastructure in code supports the addition of TCP DNS queries, but it's currently throws a NotImplementedException(). Finish up adding TCP support.