[net-dns-users] Bug report: Net::DNS::Zonefile fails to read escaped parenthesis

[Chris Buxton]

On Jun 18, 2013, at 6:34 AM, Bob Harold <rharolde at umich.edu> wrote:

> Section 2.3.1 restricts domain names to letters, digits, and hyphen, but the wording is pretty wishy-washy "Preferred Name Syntax".
> Section 5.1 allows files to use \X and \DDD but it is not clear if that includes domain names, or is for other fields, like text records, soa email fields (the example given), SPF records, etc.
> The caveat is still that non-standard domain names won't work with all applications, and are best avoided.  Use at your own risk.

Working from memory...

Hostnames are (supposed to be) restricted to letters, numbers, and hyphens. Domain names in general are fully 8 bit, other than the special character * and the terminal \000, except with regard to letter case. Representation in zone files of special characters follows a variety of escaping rules -- "\(" simply represents a "(" character.

A domain is a hostname if any of the following are true:

- the name owns an address record
- the name appears on the right hand side of an MX or SRV record
- the name owns an MX record

Chris