NAME¶
Data::Validate::Domain - domain validation methods
SYNOPSIS¶
use Data::Validate::Domain qw(is_domain);
# as a function
my $test = is_domain($suspect);
die "$test is not a domain" unless defined $test;
or
my $test = is_domain($suspect,\%options);
die "$test is not a domain" unless defined $test;
# or as an object
my $v = Data::Validate::Domain->new(%options);
my $test = $v->is_domain($suspect);
die "$test is not a domain" unless defined $test;
DESCRIPTION¶
This module collects domain validation routines to make input validation, and
untainting easier and more readable.
All functions return an untainted value if the test passes, and undef if it
fails. This means that you should always check for a defined status
explicitly. Don't assume the return will be true. (e.g. is_username('0'))
The value to test is always the first (and often only) argument.
FUNCTIONS¶
- new - constructor for OO usage
-
$obj = Data::Validate::Domain->new();
my %options = (
domain_allow_underscore => 1,
);
or
my %options = (
domain_allow_single_label => 1,
domain_private_tld => {
'privatetld1 ' => 1,
'privatetld2' => 1,
}
);
or
my %options = (
domain_allow_single_label => 1,
domain_private_tld => qr /^(?:privatetld1|privatetld2)$/,
);
$obj = Data::Validate::Domain->new(%options);
- Description
- Returns a Data::Validator::Domain object. This lets you access all the
validator function calls as methods without importing them into your
namespace or using the clumsy
Data::Validate::Domain::function_name() format.
- Options
- domain_allow_underscore
- According to RFC underscores are forbidden in "hostnames" but
not "domainnames". By default is_domain,is_domain_label, and
is_hostname will fail if you include underscores, setting this to a true
value with authorize the use of underscores in all functions.
- domain_allow_single_label
- By default is_domain will fail if you ask it to verify a domain that only
has a single label i.e. 'neely.cx' is good, but 'com' would fail. If you
set this option to a true value then is_domain will allow single label
domains through. This is most likely to be useful in combination with
domain_private_tld
- domain_private_tld
- By default is_domain requires all domains to have a valid TLD (i.e. com,
net, org, uk, etc), this is verified using the Net::Domain::TLD module.
This behavior can be extended in two different ways. Either a hash
reference can be supplied keyed by the additional TLD's, or you can supply
a precompiled regular expression.
NOTE: The TLD is normalized to the lower case form prior to the check being
done. This is done only for the TLD check, and does not alter the output
in any way.
The hash reference example:
domain_private_tld => {
'privatetld1 ' => 1,
'privatetld2' => 1,
}
The precompiled regualar expression example:
domain_private_tld => qr /^(?:privatetld1|privatetld2)$/,
- Returns
- Returns a Data::Validate::Domain object
- is_domain - does the value look like a domain name?
-
is_domain($value);
or
$obj->is_domain($value);
or
is_domain($value,\%options);
or
$obj->is_domain($value,\%options);
- Description
- Returns the untainted domain name if the test value appears to be a
well-formed domain name.
Note: See new for list of options and how those alter the behavior of
this funciton.
- Arguments
- $value
- The potential domain to test.
- Returns
- Returns the untainted domain on success, undef on failure.
- Notes, Exceptions, & Bugs
- The function does not make any attempt to check whether a domain actually
exists. It only looks to see that the format is appropriate.
A dotted quad (such as 127.0.0.1) is not considered a domain and will return
false. See Data::Validate::IP(3) for IP Validation.
Performs a lookup via Net::Domain::TLD to verify that the TLD is valid for
this domain.
Does not consider "domain.com." a valid format.
- From RFC 952
-
A "name" (Net, Host, Gateway, or Domain name) is a text string up
to 24 characters drawn from the alphabet (A-Z), digits (0-9), minus
sign (-), and period (.). Note that periods are only allowed when
they serve to delimit components of "domain style names".
No blank or space characters are permitted as part of a
name. No distinction is made between upper and lower case. The first
character must be an alpha character [Relaxed in RFC 1123] . The last
character must not be a minus sign or period.
- From RFC 1035
-
labels 63 octets or less
names 255 octets or less
[snip] limit the label to 63 octets or less.
To simplify implementations, the total length of a domain name (i.e.,
label octets and label length octets) is restricted to 255 octets or
less.
- From RFC 1123
-
One aspect of host name syntax is hereby changed: the
restriction on the first character is relaxed to allow either a
letter or a digit. Host software MUST support this more liberal
syntax.
Host software MUST handle host names of up to 63 characters and
SHOULD handle host names of up to 255 characters.
- is_hostname - does the value look like a hostname
-
is_hostname($value);
or
$obj->is_hostname($value);
or
is_hostname($value,\%options);
or
$obj->is_hostname($value,\%options);
- Description
- Returns the untainted hostname if the test value appears to be a
well-formed hostname.
Note: See new for list of options and how those alter the behavior of
this funciton.
- Arguments
- $value
- The potential hostname to test.
- Returns
- Returns the untainted hostname on success, undef on failure.
- Notes, Exceptions, & Bugs
- The function does not make any attempt to check whether a hostname
actually exists. It only looks to see that the format is appropriate.
Functions much like is_domain, except that it does not verify whether or not
a valid TLD has been supplied and allows for there to only be a single
component of the hostname (i.e www)
Hostnames might or might not have a valid TLD attached.
- is_domain_label - does the value look like a domain label?
-
is_domain_label($value);
or
$obj->is_domain_label($value);
or
is_domain_label($value,\%options);
or
$obj->is_domain_label($value,\%options);
- Description
- Returns the untainted domain label if the test value appears to be a
well-formed domain label.
Note: See new for list of options and how those alter the behavior of
this funciton.
- Arguments
- $value
- The potential ip to test.
- Returns
- Returns the untainted domain label on success, undef on failure.
- Notes, Exceptions, & Bugs
- The function does not make any attempt to check whether a domain label
actually exists. It only looks to see that the format is appropriate.
SEE ALSO¶
[RFC 1034] [RFC 1035] [RFC 2181] [RFC 1123]
- Data::Validate(3)
- Data::Validate::IP(3)
AUTHOR¶
Neil Neely <
neil@neely.cx>.
ACKNOWLEDGEMENTS¶
Thanks to Richard Sonnen <
sonnen@richardsonnen.com> for writing
the Data::Validate module.
Thanks to Len Reed <
lreed@levanta.com> for helping develop the
options mechanism for Data::Validate modules.
COPYRIGHT AND LICENSE¶
Copyright (c) 2005-2007 Neil Neely.
This library is free software; you can redistribute it and/or modify it under
the same terms as Perl itself, either Perl version 5.8.2 or, at your option,
any later version of Perl 5 you may have available.