% JSON Domain Format as Implemented by Pdns-Pipe-Nmc
+This document is based on
+[Namecoin Domain Name Specification](https://wiki.namecoin.info/index.php?title=Domain_Name_Specification).
+It tries to follow it closely, and clarify parts that are not
+specified, or specified ambiguously, in the original document.
+
+One notable deviation is the specification of `"delegate"` and `"import"`
+attributes: domain objects to which their value point are
+replacing/merging to the domain object in which they are defined.
+This seems to be in line with at least one existing "real world"
+implementation.
+
+This specification is implemented by the `pdns-pipe-nmc` program.
+
## Data Format
### `DomObj` Object
-`DomObj` either a `String` containing a dotted quad (see Note below),
-or a JSON `Map`, with the following attributes, all optional:
+`DomObj` is a data structure that is associated with an FQDN. It is
+either a `String` containing a dotted quad (see Note below), or a
+JSON `Map`, with the following attributes, all optional:
| Key | Type | Comment |
|-------------|---------------------------------------|--------------------------------------------|
| i2p | I2pObj | |
| freenet | String | |
| alias | String | Nullifies other attributes |
-| translate | String | Nullifies other attributes |
+| translate | String | Nullifies the "map" attribute |
| email | String | Used in `SOA` |
| loc | String | Format suitable for `LOC` |
| info | JsonObj | Currently unspecified |
| 2 | Int | Priority |
| 3 | Int | Weight |
| 4 | Int | Port |
-| 5 | String | Hostname |
+| 5 | String | FQDN |
#### Notes
corresponding to the FQDN "sub.dom.bit" with the value
```
-"service": [ ["imap", "tcp", 0, 0, 143, "mail.host.com." ],
- ["smtp", "tcp", 0, 0, 25, "relay.host.com."] ]
+"service": [ ["imap", "tcp", 0, 0, 143, "mail.host.com" ],
+ ["smtp", "tcp", 0, 0, 25, "relay.host.com"] ]
```
corresponds to two `SRV` RRs at two different points in the
sub.dom.bit. IN MX 0 relay.host.com.
```
+Note: Hostname element **must** be specified as fully qualified domain
+name of the host, and **must not** terminate with a dot.
+This requirement seems to be in line with many existing definitions in
+the blockchain; however it deviates from the BIND zone file format, in
+which names that have not terminating dot are automatically expanded
+by attaching the current origin zone to the end of the name.
+
#### ip attribute
Contains a list of strings representing IPv4 addresses in dotted
Does not translate into any DNS RR. Contains Tor hidden service address.
+```
+"tor": "eqt5g4fuenphqinx.onion"
+```
+
#### i2p attribute
-Does not translate into any DNS RR. Contains an object with three
+Does not translate into any DNS RR. It is a JSON Map with three
optional String attributes: `"destination"`, `"name"` and `"b32"`.
+```
+"i2p": { "destination": "XaZscx...0jGAAAA"
+ , "name": "example.i2p"
+ , "b32" : "ukeu...nkdq.b32.i2p"
+ }
+```
+
#### freenet attribute
Does not translate into any DNS RR. Contains Freesite key.
+```
+"freenet": "USK@0I8g...xbZ4,AQACAAE/Example/42/"
+```
+
#### alias attribute
-Translates into `CNAME` RR. Invalidates all other attributes except
-the element of the `"map"` with empty key. Such element is analysed
-and its contents merged into the base domain before the check.
+Translates into `CNAME` RR. Invalidates all other attributes.
+
+```
+"alias": "realhost.example.bit"
+```
+
+Notes:
+* Hostname **must** be specified as fully qualified domain
+ name of the host, and **must not** terminate with a dot.
+* Element of the `"map"` with empty key, `"delegate"` and `"import"`
+ are processed before this invalidation takes place.
#### translate attribute
Translates into `DNAME` RR. Invalidates the contents of the `"map"`
-attribute, except the element of the `"map"` with empty key. Such
-element is analysed and its contents merged into the base domain
-before the check.
+attribute.
+
+```
+"translate": "otherhost.bit"
+```
+
+Notes:
+* Hostname **must** be specified as fully qualified domain
+ name of the host, and **must not** terminate with a dot.
+* Element of the `"map"` with empty key, `"delegate"` and `"import"`
+ are processed before this invalidation takes place.
#### email attribute
value `"email":"user@domain.tld"` becomes `user.domain.tld.`
in the DNS record.
+```
+"email": "hostmaster@example.bit"
+```
+
#### loc attribute
Translates into `LOC` RR. Value must conform to the format defined
by [RFC-1876](http://tools.ietf.org/html/rfc1876).
+```
+"loc": "46 31 18.000 N 6 34 26.000 E 401.00m 1m 10000m 10m"
+```
+
#### info attribute
Does not translate into any DNS RR. Contains a JSON object with
-format unspecified at the time of this writing.
+format unspecified at the time of this writing. Intented for
+the registrant information.
#### ns attribute
-Translates into `NS` RR. Invalidates all other attributes, except
-the element of the `"map"` with empty key. Such element is analysed
-and its contents merged into the base domain before the check.
+Translates into `NS` RR. Because it effectively delegates all
+control over the domain to external nameservers, it also invalidates
+all other attributes.
+
+```
+"ns": ["ns.myserver.net", "192.168.3.4"]
+```
+
+Notes:
+* Hostname **must** be specified as fully qualified domain
+ name of the host, and **must not** terminate with a dot.
+* Element of the `"map"` with empty key, `"delegate"` and `"import"`
+ are processed before this invalidation takes place.
#### delegate attribute
Does not translate into any DNS RR. Instead, the value is used as
a key for namecoin lookup (i.e. the value must be specified with
the namespace prefix), and the result of the lookup replaces all
-other attributes, except the element of the `"map"` with empty key.
-Such element is analysed and its contents merged into the base
-domain before the check.
+other attributes
+
+```
+"delegate": "s/example74845"
+```
+
+Notes:
+* Element of the `"map"` with empty key, `"delegate"` and
+ `"import"` are processed before this invalidation takes place.
+* Unlike many other attributes, this can only contain a single
+ string as the value, rather than a list.
#### import attribute
Does not translate into any DNS RR. Instead, the value is used as
-a key for namecoin lookup (i.e. the value must be specified with
+the key for namecoin lookup (i.e. the value must be specified with
the namespace prefix), and the result of the lookup is merged with
the current domain object.
+```
+"import": ["dd/example", "s/example6473"]
+```
+
#### map attribute
JSON Map object containing subdomain names as its keys and domain
the empty element of the `"map"` has been recursively merged into
the current object.
+```
+"map": { "www": { "alias" : "www.example.com" }
+ , "www2": { "delegate": "d/example" }
+ }
+```
+
+Note: When a key contains dots ".", it is converted to a nested
+map. Empty elements in the result of split, such as when a dot is
+at the beginning or at the end of the key, or there are
+consequitive dots, are diagnosed as erroneous data.
+
+```
+"map": { "www.uk": { "alias" : "www.example.co.uk" }
+ , "www..us": { "alias" : "www.example.com" }
+ , "smtp.us.": { "alias" : "smtp.example.com" }
+```
+
+is equivalent to
+
+```
+"map": { "uk": { "map": { "www": { "alias" : "www.example.co.uk" }}}
+ , "us": { "map": { "www": { "alias" : "www.example.com" }
+ , "smtp": { "alias" : "smtp.example.com" }}
+ }
+ }
+```
+
#### fingerprint attribute
Does not translate into any DNS RR. Contains a list of TLS
Intended to carry attributes as per
[RFC-6698](http://tools.ietf.org/html/rfc6698) ("DANE").
-As of this writing, the specification is under discussion.
+
+```
+"tls": {
+ "tcp": {
+ { "443": [ [1, "660008F9...7621B787", 1] ]
+ , "25": [ [1, "660008F9...7621B787", 1] ]
+ }
+ }
+ }
+```
+
+translates into:
+
+```
+_443._tcp TLSA (3 0 1 660008F9...7621B787)
+_25._tcp TLSA (3 0 1 660008F9...7621B787)
+```
+
+The third element of the `TlsObj` heterogenous array is an extention
+to the DANE definition. Value `0` means that this rule is not enforced
+upon subdomains, value `1` means that it is enforced on subdomains.
+Rule defined inside a subdomain `DomObj` that specifies `0` on a rule
+existing in upper domain, that specifies `1` should be ignored. I.e.
+subdomain rule cannot revoke enforcement imposed by an upper domain rule.
#### ds attribute
Translates into `DS` RR. Carries attributes defined by
[RFC-4034](http://tools.ietf.org/html/rfc4034).
+```
+"ds": [ [31381,8,1,"pA1W...ceTI="]
+ , [31381,8,2,"toHB...ndexitQ6j8E="]
+ ]
+```
+
### Lookup Sequence
Assuming a query is performed for
"normalized" by removal of attributes that are nullified by the
presence of other attributes.
-Note that the process involves recursion nested to three levels.
+Note that the process involves recursion nested levels deep.
### Merging Procedure