dns.name

Module name

DNS Names.

Classes

EmptyLabel
A DNS label is empty.

BadEscape
An escaped code in a text format of DNS name is invalid.

BadPointer
A DNS compression pointer points forward instead of backward.

BadLabelType
The label type in DNS name wire format is unknown.

NeedAbsoluteNameOrOrigin
An attempt was made to convert a non-absolute name to wire when there was also a non-absolute (or missing) origin.

NameTooLong
A DNS name is > 255 octets long.

LabelTooLong
A DNS label is > 63 octets long.

AbsoluteConcatenation
An attempt was made to append anything other than the empty name to an absolute DNS name.

NoParent
An attempt was made to get the parent of the root name or the empty name.

Name
A DNS name.

Functions

[hide private]

string

_escapify(label, unicode_mode=False)
Escape the characters in label which need it.

source code

_validate_labels(labels)
Check for empty labels in the middle of a label sequence, labels that are too long, and for too many labels.

source code

_ensure_bytes(label)

source code

dns.name.Name object

from_unicode(text, origin=<DNS name .>)
Convert unicode text into a Name object.

source code

dns.name.Name object

from_text(text, origin=<DNS name .>)
Convert text into a Name object.

source code

(dns.name.Name object, int) tuple

from_wire(message, current)
Convert possibly compressed wire format into a Name.

source code

Variables

[hide private]

maxint = 9223372036854775807

NAMERELN_NONE = 0

NAMERELN_SUPERDOMAIN = 1

NAMERELN_SUBDOMAIN = 2

NAMERELN_EQUAL = 3

NAMERELN_COMMONANCESTOR = 4

_escaped = bytearray(b'"().;\\@$')

dns.name.Name object

root = <DNS name .>
The DNS root name.

dns.name.Name object

empty = <DNS name @>
The empty DNS name.

__package__ = 'dns'

Function Details

[hide private]

_escapify(label, unicode_mode=False)

source code

Escape the characters in label which need it.

Parameters:

unicode_mode - escapify only special and whitespace (<= 0x20) characters

Returns: string

the escaped string

_validate_labels(labels)

source code

Check for empty labels in the middle of a label sequence, labels that are too long, and for too many labels.

Raises:

NameTooLong - the name as a whole is too long
EmptyLabel - a label is empty (i.e. the root label) and appears in a position other than the end of the label sequence

from_unicode(text, origin=<DNS name .>)

source code

Convert unicode text into a Name object.

Labels are encoded in IDN ACE form.

Returns: dns.name.Name object

from_wire(message, current)

source code

Convert possibly compressed wire format into a Name.

Parameters:

message (string) - the entire DNS message
current (int) - the offset of the beginning of the name from the start of the message

Returns: (dns.name.Name object, int) tuple

a tuple consisting of the name that was read and the number of bytes of the wire format message which were consumed reading it

Raises:

dns.name.BadPointer - a compression pointer did not point backwards in the message
dns.name.BadLabelType - an invalid label type was encountered.