draft-ietf-asid-whoispp-00.txt   draft-ietf-asid-whoispp-01.txt 
ASID Working Group Patrik Faltstrom ASID Working Group Patrik Faltstrom
Internet-Draft Tele 2 Internet-Draft Tele 2
Expires: May 1997 November 1996 Expires: September 1997 Sima Newell
draft-ietf-asid-whoispp-00.txt draft-ietf-asid-whoispp-01.txt Bunyip Information Systems Inc.
Replaces: RFC-1835 Replaces: RFC-1835 Leslie L. Daigle
Bunyip Information Systems Inc.
Architecture of the WHOIS++ service Architecture of the Whois++ service
Status of this Memo Status of this Memo
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Abstract Abstract
This document describes WHOIS++, an extension to the trivial WHOIS This document describes Whois++, an extension to the trivial WHOIS
service described in RFC 954 to permit WHOIS-like servers to make service described in RFC 954 to permit WHOIS-like servers to make
available more structured information to the Internet. We describe available more structured information to the Internet. We describe
an extension to the simple WHOIS data model and query protocol and a an extension to the simple WHOIS data model and query protocol and a
companion extensible, distributed indexing service. A number of companion extensible, distributed indexing service. A number of
options have also been added such as the use of multiple languages options have also been added such as the use of multiple languages
and character sets, more advanced search expressions, structured data and character sets, more advanced search expressions, structured data
and a number of other useful features. An optional authentication and a number of other useful features. An optional authentication
mechanism for protecting all or part of the associated WHOIS++ mechanism for protecting all or part of the associated Whois++
information database from unauthorized access is also described. information database from unauthorized access is also described.
Table of Contents Table of Contents
Part I - WHOIS++ Overview ................................. Part I - Whois++ Overview .................................
1.1. Purpose and Motivation .............................. 1.1. Purpose and Motivation ..............................
1.2. Basic Information Model ............................. 1.2. Basic Information Model .............................
1.2.1. Changes to the current WHOIS Model ................ 1.2.1. Changes to the current WHOIS Model ................
1.2.2. Registering WHOIS++ servers ....................... 1.2.2. Registering Whois++ servers .......................
1.2.3. The WHOIS++ Search Selection Mechanism ............ 1.2.3. The Whois++ Search Selection Mechanism ............
1.2.4. The WHOIS++ Architecture .......................... 1.2.4. The Whois++ Architecture ..........................
1.3. Indexing in WHOIS++ ................................. 1.3. Indexing in Whois++ .................................
1.4. Getting Help ........................................ 1.4. Getting Help ........................................
1.4.1. Minimum HELP Required ............................. 1.4.1. Minimum HELP Required .............................
1.5. Options and Constraints ............................. 1.5. Options and Constraints .............................
1.6. Formatting Responses ................................ 1.6. Formatting Responses ................................
1.7. Reporting Warnings and Errors ....................... 1.7. Reporting Warnings and Errors .......................
1.8. Privacy and Security Issues ......................... 1.8. Privacy and Security Issues .........................
Part II - WHOIS++ Implementation .......................... Part II - Whois++ Implementation ..........................
2.1. The WHOIS++ interaction model ....................... 2.1. The Whois++ interaction model .......................
2.2. The WHOIS++ Command set ............................. 2.2. The Whois++ Command set .............................
2.2.1. System Commands ................................... 2.2.1. System Commands ...................................
2.2.1.1. The COMMANDS command ............................ 2.2.1.1. The COMMANDS command ............................
2.2.1.2. The CONSTRAINTS command ......................... 2.2.1.2. The CONSTRAINTS command .........................
2.2.1.3. The DESCRIBE command ............................ 2.2.1.3. The DESCRIBE command ............................
2.2.1.4. The HELP command ................................ 2.2.1.4. The HELP command ................................
2.2.1.5. The LIST command ................................ 2.2.1.5. The LIST command ................................
2.2.1.6. The POLLED-BY command ........................... 2.2.1.6. The POLLED-BY command ...........................
2.2.1.7. The POLLED-FOR command .......................... 2.2.1.7. The POLLED-FOR command ..........................
2.2.1.8. The SHOW command ................................ 2.2.1.8. The SHOW command ................................
2.2.1.9. The VERSION command ............................. 2.2.1.9. The VERSION command .............................
2.2.2. The Search Command ................................ 2.2.2. The Search Command ................................
2.2.2.1. Format of a Search Term ......................... 2.2.2.1. Format of a Search Term .........................
2.2.2.2. Format of a Search String ....................... 2.2.2.2. Format of a Search String .......................
2.3. WHOIS++ Constraints ................................. 2.3. Whois++ Constraints .................................
2.3.1. Required Constraints .............................. 2.3.1. Required Constraints ..............................
2.3.2. Optional CONSTRAINTS .............................. 2.3.2. Optional CONSTRAINTS ..............................
2.3.2.1. The SEARCH Constraint ........................... 2.3.2.1. The SEARCH Constraint ...........................
2.3.2.2. The FORMAT Constraint ........................... 2.3.2.2. The FORMAT Constraint ...........................
2.3.2.3. The MAXFULL Constraint .......................... 2.3.2.3. The MAXFULL Constraint ..........................
2.3.2.4. The MAXHITS Constraint .......................... 2.3.2.4. The MAXHITS Constraint ..........................
2.3.2.5. The CASE Constraint ............................. 2.3.2.5. The CASE Constraint .............................
2.3.2.6. The AUTHENTICATE Constraint ..................... 2.3.2.6. The AUTHENTICATE Constraint .....................
2.3.2.7. The NAME Constraint ............................. 2.3.2.7. The NAME Constraint .............................
2.3.2.8. The PASSWORD Constraint ......................... 2.3.2.8. The PASSWORD Constraint .........................
skipping to change at line 110 skipping to change at line 111
2.4.3.5. SERVERS-TO-ASK Response ......................... 2.4.3.5. SERVERS-TO-ASK Response .........................
2.4.4. System Generated Messages ......................... 2.4.4. System Generated Messages .........................
2.5. Compatibility with Older WHOIS Servers .............. 2.5. Compatibility with Older WHOIS Servers ..............
3. Miscellaneous ......................................... 3. Miscellaneous .........................................
3.1. Acknowledgements .................................... 3.1. Acknowledgements ....................................
3.2. References .......................................... 3.2. References ..........................................
3.3. Authors' Addresses .................................. 3.3. Authors' Addresses ..................................
Appendix A - Some Sample Queries .......................... Appendix A - Some Sample Queries ..........................
Appendix B - Some sample responses ........................ Appendix B - Some sample responses ........................
Appendix C - Sample responses to system commands .......... Appendix C - Sample responses to system commands ..........
Appendix D - Sample whois++ session ....................... Appendix D - Sample Whois++ session .......................
Appendix E - System messages .............................. Appendix E - System messages ..............................
Appendix F - The WHOIS++ BNF Grammar ...................... Appendix F - The Whois++ Input Syntax .....................
Appendix G - Description of Regular expressions ........... Appendix G - The Whois++ Response Syntax ..................
Appendix H - Description of Regular expressions ...........
1. Part I - WHOIS++ Overview 1. Part I - Whois++ Overview
1.1. Purpose and Motivation 1.1. Purpose and Motivation
The current NIC WHOIS service [HARR85] is used to provide a very The current NIC WHOIS service [HARR85] is used to provide a very
limited directory service, serving information about a small number limited directory service, serving information about a small number
of Internet users registered with the DDN NIC. Over time the basic of Internet users registered with the DDN NIC. Over time the basic
service has been expanded to serve additional information and similar service has been expanded to serve additional information and similar
services have also been set up on other hosts. Unfortunately, these services have also been set up on other hosts. Unfortunately, these
additions and extensions have been done in an ad hoc and additions and extensions have been done in an ad hoc and
uncoordinated manner. uncoordinated manner.
skipping to change at line 143 skipping to change at line 145
protocol. protocol.
Despite its utility, the current NIC WHOIS service cannot function as Despite its utility, the current NIC WHOIS service cannot function as
a general White Pages service for the entire Internet. Given the a general White Pages service for the entire Internet. Given the
inability of a single server to offer guaranteed response or inability of a single server to offer guaranteed response or
reliability, the huge volume of traffic that a full scale directory reliability, the huge volume of traffic that a full scale directory
service will generate and the potentially huge number of users of service will generate and the potentially huge number of users of
such a service, such a trivial architecture is obviously unsuitable such a service, such a trivial architecture is obviously unsuitable
for the current Internet's needs for information services. for the current Internet's needs for information services.
This document describes the architecture and protocol for WHOIS++, a This document describes the architecture and protocol for Whois++, a
simple, distributed and extensible information lookup service based simple, distributed and extensible information lookup service based
upon a small set of extensions to the original WHOIS information upon a small set of extensions to the original WHOIS information
model. These extensions allow the new service to address the model. These extensions allow the new service to address the
community's needs for a simple directory service, yet the extensible community's needs for a simple directory service, yet the extensible
architecture is expected to also allow it to find application in a architecture is expected to also allow it to find applications in a
number of other information service areas. number of other information service areas.
Added features include an extension to the trivial WHOIS data model Added features include an extension to the trivial WHOIS data model
and query protocol and a companion extensible, distributed indexing and query protocol and a companion extensible, distributed indexing
service. A number of other options have also been added, like boolean service. A number of other options have also been added, like boolean
operators, more powerful search constraints and search methods, and operators, more powerful search constraints and search methods. In
most specificly structured the data to make both the client and the addition, the data has been structured to make both the client and
server part of the dialogue more stringent and parseable. An optional server elements of the dialogue more stringent and easily
authentication mechanism for protecting all or parts of the parsed. An optional authentication mechanism for protecting all or
associated WHOIS++ information database from unauthorized access is parts of the associated Whois++ information database from
also briefly described. unauthorized access is also briefly described.
The basic architecture of WHOIS++ allows distributed maintenance of The architecture of Whois++ allows distributed maintenance of
the directory contents and the use of the WHOIS++ indexing service the directory contents and the use of the Whois++ indexing service
for locating additional WHOIS++ servers. Although a general overview for locating additional Whois++ servers. Although a general overview
of this service is included for completeness, the indexing extensions of this service is included for completeness, the indexing extensions
are described in a separate paper. are described described separately in [WINDX].
WHOIS++ is though not backward compatible with WHOIS.
1.2. Basic Information Model It should be noted that Whois++ is not backward compatible with WHOIS.
The WHOIS++ service is centered in a recommendation to structure user 1.2. The Whois++ Information Model
information around a series of standardized information templates.
Such templates consist of ordered sets of data elements (or
attribute-value pairs).
It is intended that adding such structured templates to a server and The Whois++ service is based on the use of information templates, which
subsequently identifying and searching them be simple tasks. The consist of ordered sets of data elements (or attribute-value pairs).
creation and use of customized templates should also be possible with It underlying recommendation is to use standardized templates where
little effort, although their use should be discouraged where available.
appropriate standardized templates exist.
Registration and schema definitions are done attribute per attribute, It is intended that adding structured template types to a server
so a client that receives a record parses the record structure and subsequently searching through information stored in templates
attribute per attribute. Because of this, the client does not have of a specified type should be simple tasks. The creation and use of
to know the structure of the attribute values more than the whole customized templates should also be possible with little effort, although
template. If the client sees an unknown attribute, skip that one their use is discouraged where appropriate standardized templates exist.
and continue parsing on the next.
A server that defines schemas can because of this add their own Registration and schema definitions are done on an attribute by
unregistered attributes to a well-defined template type. attribute basis, so a client that receives a record parses the
record structure one attribute at a time. Because of this system,
the client does not need to know the structure of the whole record,
only individual attributes. If the client sees an unknown
attribute, it will skip that one and continue parsing the
subsequent attributes. A server that defines schemas can therefore
add its own unregistered attributes to a well-defined template type.
We also offer methods to allow the user to constrain searches to We also offer methods to allow the user to constrain searches to
desired attributes or template types, in addition to the existing desired attributes or template types, in addition to the existing
commands for specifying handles or simple strings. commands for specifying handles or simple strings.
It is expected that the minimalist approach we have taken will find It is expected that the minimalist approach we have taken will find
application where the high cost of configuring and operating applications where the high cost of configuring and operating
traditional White Pages services can not currently be justified. traditional White Pages services can not currently be justified.
Also note that the architecture makes no assumptions about the search Note also that the architecture makes no assumptions about the search
and retrieval mechanisms used within individual servers. Operators and retrieval mechanisms used within individual servers. Operators
are free to use dedicated database formats, fast indexing software or are free to use dedicated database formats, fast indexing software or
even provide gateways to other directory services to store and even provide gateways to other directory services to store and
retrieve information, if desired. retrieve information. The Whois++ server simply functions as a
known front end, offering a simple data model and communicating
The WHOIS++ server simply functions as a known front end, offering a through a well known port and query protocol. The format of both
simple data model and communicating through a well known port and queries and replies has been structured to allow the use of client
query protocol. The format of both queries and replies has been software for generating searches and displaying the results. At the
structured to allow the use of client software for generating same time, some effort has been made to keep responses legible (to
searches and displaying the results. At the same time, some effort some degree) by human users, both to ensure low entry cost and to
has been made to keep responses at least to some degree readible by ease debugging.
humans, to ensure low entry cost and to ease debugging.
The actual implemention details of an individual WHOIS++ search The actual implemention details of an individual Whois++ search
engine are left to the imagination of the implementor and it is hoped engine are left to the imagination of the implementor. It is hoped
that the simple, extensible approach taken will encourage that the simple, extensible approach taken will encourage
experimentation and the development of improved search engines. experimentation and the development of improved search engines.
1.2.1. Changes to the current WHOIS Model 1.2.1. Changes to the current WHOIS Model
The current WHOIS service is based upon an extremely simple data The current WHOIS service is based upon an extremely simple data
model. The NIC WHOIS database consists of a series of individual model. The NIC WHOIS database consists of a series of individual
records, each of which is identified by a single unique identifer records, each of which is identified by a single unique identifer
(the "handle"). Each record contains one or more lines of (the "handle"). Each record contains one or more lines of
information. Currently, there is no structure or implicit ordering of information. Currently, there is no structure or implicit ordering of
this information, although by implication each record is concerned this information, although each record is implicitly concerned
with information about a single user or service. with information about a single user or service.
We have implemented two basic changes to this model. First, we have We have implemented two basic changes to this model. First, we have
structured the information within the database as collections of data structured the information within the database as collections of data
elements, or simple attribute/value pairs. Each individual record elements that are simple attribute/value pairs. Each individual record
contains a specified ordered set of these data elements. contains a specified ordered set of these data elements.
Secondly, we have introduced typing of the database records. In Second, we have introduced the classing of database records into
effect, each record is based upon one of a specified set of template types. In effect, each record is based upon one template of a
templates, each containing a finite and specified number of data specified set; each template contains a finite and specified number
elements. This allow users to easily limit searches to specific of data elements. This classing allows users to limit searches
collections of information, such as information about users, to specific collections of information, such as information about
services, abstracts of papers, descriptions of software, and so on. users, services, abstracts of papers, or descriptions of software.
It is though possible, because of the typing per attribute, to add Since the data typing is done at the attribute level, not the template
non-standard attributes to a well-known template type. level, it is also possible to add non-standard attributes to a
well-known template type.
As a final extension, we require that each individual WHOIS++ As an addition to the model, we require that each individual Whois++
database on the Internet be assigned a unique handle, analogous to database on the Internet be assigned a unique handle, analogous to
the handle associated with each database record. the handle associated with each database record.
The WHOIS++ database structure is shown in Fig. 1. The Whois++ database structure is shown in Fig. 1.
1.2.2. Registering WHOIS++ servers
We propose that individual database handles be registered through the
Internet Assigned Numbers Authority (the IANA), ensuring their
uniqueness. This will allow us to specify each WHOIS++ entry on the
Internet as a unique pair consisting of a server handle and a record
handle.
A unique registered handle is preferable to using the host's IP
address, since it is conceivable that the WHOIS++ server for a
particular domain may move over time. If we preserve the unique
WHOIS++ handle in such cases we have the option of using it for
resource discovery and networked information retrieval (see [IIIR]
for a discussion of resource and discovery and support issues).
There are many ways of guaranteeing uniqueness of server handles; we
will discuss them in a separate paper.
We believe that organizing information around a series of such
templates will make it easier for administrators to gather and
maintain this information and thus encourage them to make such
information available. At the same time, as users become more
familiar with the data elements available within specific templates
they will be better able to specify their searches, leading to a more
useful service.
______________________________________________________________________ ______________________________________________________________________
| | | |
| + Single unique WHOIS++ server handle | | + Single unique Whois++ server handle |
| | | |
| _______ _______ _______ | | _______ _______ _______ |
| handle3 |.. .. | handle6 |.. .. | handle9 |.. .. | | | handle3 |.. .. | handle6 |.. .. | handle9 |.. .. | |
| _______ | _______ | _______ | | | _______ | _______ | _______ | |
| handle2 |.. .. | handle5 |.. .. | handle8 |.. .. | | | handle2 |.. .. | handle5 |.. .. | handle8 |.. .. | |
| _______ | _______ | _______ | | | _______ | _______ | _______ | |
| handle1 |.. .. | handle4 |.. .. | handle7 |.. .. | | | handle1 |.. .. | handle4 |.. .. | handle7 |.. .. | |
| |.. .. | |.. .. | |.. .. | | | |.. .. | |.. .. | |.. .. | |
| ------- ------- ------- | | ------- ------- ------- |
| Template Template Template | | Template Template Template |
| Type 1 Type 2 Type 3 | | Type 1 Type 2 Type 3 |
| | | |
| | | |
| | | |
| | | |
| Fig.1 - Structure of a WHOIS++ database. | | Fig.1 - Structure of a Whois++ database. |
| | | |
| Notes: - Entire database is identified by a single unique WHOIS++ | | Notes: - Entire database is identified by a single unique Whois++ |
| serverhandle. | | serverhandle. |
| - Each record has a single unique handle and a specific set | | - Each record has a single unique handle. |
| of attributes, determined by the template type used. | | - Each record has a specific set of attributes, which is |
| - Each value associated with an attribute can be any ASCII | | determined by the Template Type used. |
| string of an arbitrary length. | | - Each value associated with an attribute is a text string |
| of an arbitrary length. |
|______________________________________________________________________| |______________________________________________________________________|
1.2.3. The WHOIS++ Search Selection Mechanism 1.2.2. Registering Whois++ servers
We propose that individual database handles be registered through the
Internet Assigned Numbers Authority (the IANA), ensuring their
uniqueness. This will allow us to specify each Whois++ entry on the
Internet as a unique pair consisting of a server handle and a record
handle.
A unique registered handle is preferable to using the host's IP
address, since it is conceivable that the Whois++ server for a
particular domain may move over time. If we preserve the unique
Whois++ handle in such cases we have the option of using it for
resource discovery and networked information retrieval (see [IIIR]
for a discussion of resource and discovery and support issues).
Uniqueness of server handles can be guaranteed by registering them with
IANA.
We believe that organizing information around a series of such
templates will make it easier for administrators to gather and
maintain this information and thus encourage them to make such
information available. At the same time, as users become more
familiar with the data elements available within specific templates
they will be able to specify their searches better, and the service
will become more useful.
1.2.3. The Whois++ Search Selection Mechanism
The WHOIS++ search mechanism is intended to be extremely simple. A The WHOIS++ search mechanism is intended to be extremely simple. A
search command consists of one or more search terms, with an optional search command comprises one required element and one optional
set of global constraints (specifiers that modify or control a element. The first (required) element is a set of one or more search
search). terms. The second (optional) element is a colon followed by set of
one or more global constraints, which modify or control the search.
Search terms allow the user to specify template type, attribute, Within each search term, the user may specify the template type,
value or handle that any record returns must satisfy. Each search attribute, value or handle that any record returned must satisfy. Each
term can have an optional set of local constraints that apply to only search term can have an optional set of local constraints that apply
that term. only to that term.
A WHOIS++ database may be seen as a single rolodex-like collection of A Whois++ database may be seen as a single collection of
typed records. Each term specifies a further constraint that the typed records. Each search term specifies a further constraint that the
selected set of output records must satisfy. Each term may thus be selected set of output records must satisfy. Each term may thus be
thought of as performing a subtractive selection, in the sense that thought of as performing a subtractive selection, in the sense that
any record that does not fulfil the term is discarded from the result any record that does not fulfill the term is discarded from the result
set. Boolean searches are possible by the use of AND, OR, NOT and set. Result sets can be further specified by supplying multiple search
parenthesis. terms, related by logical connectives (AND, OR, NOT).
1.2.4. The WHOIS++ Architecture 1.2.4. The Whois++ Architecture
The WHOIS++ directory service has an architecture which is separated The Whois++ directory service has an architecture which is separated
into two components; the base level server, which is described in into two components: the base level server, which is described in
this paper, and a indexing server. A single physical server can act this paper, and an indexing server (described in [WINDX]). A single
as both a base level server and an indexing server. physical server can act as both a base level server and an indexing server.
A base level server is one which contains only filled templates. An A base level server is one which contains only filled templates. An
indexing server is one which contains forward knowledge (q.v.) and indexing server is one which contains forward knowledge (q.v.) and
pointers to other indexing servers or base level servers. pointers to other indexing servers or base level servers.
1.3. Indexing in WHOIS++ 1.3. Indexing in Whois++
Indexing in WHOIS++ is used to tie together many base level servers Indexing in Whois++ is used to tie together many base level servers
and index servers into a unified directory service. and index servers into a unified directory service. For more detailed
information on this subject, see [WINDX].
Each base level server and index server which wishes to participate Each base level server and index server that is to participate
in the unified directory service must generate "forward knowledge" in the unified directory service must generate forward knowledge
for the entries it contains. One type of forward knowledge is the for the entries it contains. One type of forward knowledge is the
"centroid". "centroid".
An example of a centroid is as follows: if a whois++ server contained An example of a centroid is as follows. Consider a Whois++ server
exactly three records, as follows: that contains exactly three records:
Record 1 Record 2 Record 1 Record 2
Template: Person Template: Person Template: Person Template: Person
First-Name: John First-Name: Joe First-Name: John First-Name: Joe
Last-Name: Smith Last-Name: Smith Last-Name: Smith Last-Name: Smith
Favourite-Drink: Labatt Beer Favourite-Drink: Molson Beer Favourite-Drink: Labatt Beer Favourite-Drink: Molson Beer
Record 3 Record 3
Template: Domain Template: Domain
Domain-Name: foo.edu Domain-Name: foo.edu
skipping to change at line 378 skipping to change at line 382
Template: Domain Template: Domain
Domain-Name: foo.edu Domain-Name: foo.edu
Contact-Name: Mike Contact-Name: Mike
Foobar Foobar
An index server would then collect this centroid for this server as An index server would then collect this centroid for this server as
forward knowledge. forward knowledge.
Index servers can collect forward knowledge for any servers it Index servers can collect forward knowledge for any servers it
wishes. In effect, all of the servers that the index server knows polls. In effect, all of the servers that the index server knows
about can be searched with a single query to the index server; the about can be searched with a single query to the index server; the
index server holds the forward knowledge along with pointers to the index server holds the forward knowledge along with pointers to the
servers it indexes, and can refer the query to servers which might servers it indexes, and can refer the query to servers which might
hold information which satisfies the query. hold information which satisfies the query.
Implementors of this protocol are strongly encouraged to incorporate Implementors of this protocol are strongly encouraged to incorporate
centroid generation abilities into their servers. centroid generation abilities into their servers.
Whois++ uses the Common Indexing Protocol [ALL96] to forward Whois++ uses the Common Indexing Protocol, which was originally described
knowledge, and more specifically a centroid-like CIP Index Object. in [WINDX] as a centroid-like object to provide index information
(forward knowledge) about server contents. This work is being extended in
the IETF's FIND Working-Group.
------------------------------------------------------------------- -------------------------------------------------------------------
____ ____ ____ ____
top level | | | | top level | | | |
whois index | | | | whois index | | | |
servers ---- ---- servers ---- ----
/ \________ / / \________ /
/ \ / / \ /
____ ____ ____ ____
skipping to change at line 418 skipping to change at line 424
Fig. 2 - Indexing system architecture. Fig. 2 - Indexing system architecture.
------------------------------------------------------------------- -------------------------------------------------------------------
1.4. Getting Help 1.4. Getting Help
Another extension to the basic WHOIS service is the requirement that Another extension to the basic WHOIS service is the requirement that
all servers support at least a minimal set of help commands, allowing all servers support at least a minimal set of help commands, allowing
users to find out information about both the individual server and users to find out information about both the individual server and
the entire WHOIS++ service itself. This is done in the context of the the entire Whois++ service itself. This is done in the context of the
new extended information model by defining two specific template new extended information model by defining two specific template
formats and requiring each server to offer at least one example of formats and requiring each server to offer at least one example of
each record using these formats. The operator of each WHOIS service each record using these formats. The operator of each Whois++ service
is therefor expected to have, as a minimum, a single example of is therefor expected to have, as a minimum, a single example of
SERVICES and HELP records, which can be accessed through appropriate SERVICES and HELP records, which can be accessed through appropriate
commands. commands.
1.4.1. Minimum HELP Required 1.4.1. Minimum HELP Required
Executing the command: Executing the command:
DESCRIBE DESCRIBE
gives a brief information about the WHOIS++ server. gives a brief information about the Whois++ server.
Executing the command: Executing the command:
HELP HELP
gives a brief description of the WHOIS++ service itself. gives a brief description of the Whois++ service itself.
The text of both required helped records should contain pointers to The text of both required helped records should contain pointers to
additional help subjects that are available. additional help subjects that are available.
Executing the command: Executing the command:
HELP <searchstring> HELP <searchstring>
may give information on any topic. gives information on <searchstring>.
1.5. Options and Constraints 1.5. Options and Constraints
The WHOIS++ service is based upon a minimal core set of commands and The Whois++ service is based upon a minimal core set of commands and
controlling constraints. A small set of additional optional commands controlling constraints. A small set of additional optional commands
and constraints can be supported. These would allow users to perform and constraints can be supported by a server. These allow users to
such tasks as provide security options, modify the information perform such tasks as provide security options, modify the
contents of a server or add multilingual support. The required set of information contents of a server or add multilingual support. The
WHOIS++ commands are summarized in section 2.2. WHOIS++ constraints required set of Whois++ commands are listed in section 2.2.
are described in section 2.3. Optional constraints are described in Whois++ constraints are described in section 2.3. Optional
section 2.3.2. constraints are described in section 2.3.2.
1.6. Formatting Responses 1.6. Formatting Responses
The output returned by a WHOIS++ server is structured to allow The output returned by a Whois++ server is structured to allow
machine parsing and automated handling. Of particular interest in the machine parsing and automated handling. Of particular interest is the
ability to return summary information about a search (without having ability to return summary information about a search instead of having
to return the entire results). to return the entire results.
All output of searches will be returned in one of five output All output of searches will be returned in one of five output
formats, which will be one of FULL, ABRIDGED, HANDLE, SUMMARY or formats, which will be one of FULL, ABRIDGED, HANDLE, SUMMARY or
SERVER-TO-ASK. Note that a conforming server is only required to SERVER-TO-ASK. Note that a conforming server is only required to
support the FULL format. support the FULL format.
When available, SERVER-TO-ASK format is used to indicate that a When available, SERVER-TO-ASK format is used to indicate that a
search cannot be completed but that one or more alternative WHOIS++ search cannot be completed but that one or more alternative Whois++
servers may be able to perform the search. servers may be able to perform the search.
Details of each output format are specified in section 2.4. Details of each output format are specified in section 2.4.
1.7. Reporting Warnings and Errors 1.7. Reporting Warnings and Errors
The formatted response of WHOIS++ commands allows the encoding of The formatted response of Whois++ commands allows the encoding of
warning or error messages to simplify parsing and machine handling. warning or error messages to simplify parsing and machine handling.
The syntax of output formats are described in detail in section 2.4, The syntax of output formats are described in detail in section 2.4,
and details of WHOIS++ warnings and error conditions are given in and details of Whois++ warnings and error conditions are given in
Appendix E. Appendix E.
All system messages are numerical, but can be tagged with text. It is All system messages are numerical, but can be tagged with text. It is
the clients decision if the text is presented to the user. the client's decision if the text is presented to the user.
1.8. Privacy and Security Issues 1.8. Privacy and Security Issues
The basic WHOIS++ service was conceived as a simple, unauthenticated The basic Whois++ service was conceived as a simple, unauthenticated
information lookup service, but there are occasions when information lookup service, but there are occasions when
authentication mechanisms are required. To handle such cases, an authentication mechanisms are required. To handle such cases, one
optional mechanism is provided for authenticating each WHOIS++ optional mechanism is provided for authenticating each Whois++
transaction. transaction. This is the ability to name a (mutually-recognized)
authentication scheme in the optional AUTHENTICATE global constraint.
The current identified authentication mechanism is PASSWORD, which The one currently defined authentication scheme is PASSWORD, which
uses simple password authentication. Any other scheme name used must uses simple password authentication. Any other scheme name used must
begin with the characters "X-" and should thus be regarded as begin with the characters "X-" and should thus be regarded as
experimental and non-standard. experimental and non-standard.
Note that the WHOIS++ authentication mechanism does not dictate the Note that the Whois++ authentication mechanism does not dictate the
actual authentication scheme used, it merely provides a framework for actual authentication scheme used, it merely provides a framework for
indicating that a particular transaction is to be authenticated, and indicating that a particular transaction is to be authenticated, and
the appropriate mechanisms to use. This mechanism is extensible and the appropriate scheme to use. This mechanism is extensible and
individual implementors are free to add additional mechanisms. individual implementors are free to add additional schemes.
This document includes a very simple authentication scheme where a This document describes a very simple authentication scheme in which a
combination of username and password is sent together with the search combination of username and password is sent together with the search
string so the server can verify that the user have access to the string so the server can verify that the user have access to the
information. Note that this is NOT by any means a method recommended information. Note that this is NOT by any means a method recommended
to secure the data itself because both password and information are to secure the data itself because both password and information are
tranferred unencrypted over the network. transferred unencrypted over the network.
Given the unauthenticated nature that default services like white
pages services are, it is easy to either forget the implications of
this and just show all data to the public Internet, or think that
Internet is so dangerous that information is hidden from the Internet
so the whole idea of a global white pages service is lost. Therefore
the type of authentication scheme selected and the public nature of
the Internet environment must still be taken into consideration when
assessing the security and authentication of the information served.
A more detailed exposition on security is outside the scope of this Other, more sophisticated security and authentication schemes may
document. be proposed to address specific needs. For example, the Simple
Authentication and Security Layer (SASL) work proposed by John Myers
(particularly for POP and IMAP) may be applicable here.
2. Part II - WHOIS++ Implementation 2. Part II - Whois++ Implementation
2.1. The WHOIS++ interaction model 2.1. The Whois++ interaction model
A WHOIS++ server will normally listen for a TCP connections on the The Whois++ service has an assigned port number -- number 63.
allocated WHOIS++ port 63 (although a WHOIS++ server can be accessed However, there is nothing inherent the Whois++ protocol or interaction
over any TCP connection). Once a connection is established, the model that prevents it from being used on any TCP connection on
any port -- the specification of the connection is outside the scope
of this protocol spec. Once a connection is established, the
server issues a banner message, and listens for input. The command server issues a banner message, and listens for input. The command
specified in this input is processed and the results returned specified in this input is processed and the results returned
including an ending system message. If the optional HOLD constraint including an ending system message. If the client
has not been specified the connection is then terminated. does not specify the optional HOLD constraint, the connection is
then terminated.
If the server supports the optional HOLD constraint, and this If the server supports the optional HOLD constraint, and this
constraint is specified as part of any command, the server continues constraint is specified as part of any command, the server continues
to listen on the connection for another line of input. This cycle to listen on the connection for another (single) line of input.
continues as long as the sender continues to append the required HOLD This cycle continues as long as the sender continues to append the
constraint to each subsequent command. required HOLD constraint to each subsequent command.
At the same time, each server is permitted to set an optional timeout
value (which should be indicated in the response to the CONSTRAINTS
command). If set, the server is free to terminate an idle connection
at any time after this delay has passed with no input from the
client. If the server terminates the connection due to timeout, it
will be indicated by the system message. The timeout value is not
changeable by the client.
2.2. The WHOIS++ Command set
There are two types of WHOIS++ commands - system commands and the 2.2. The Whois++ Command set
WHOIS++ search command.
The WHOIS++ command set consists of a core set of required systems The Whois++ command set consists of a core set of required systems
commands, a single required search command and an set of optional commands, a single required search command and an set of optional
system commands which support features that are not required by all system commands which support features that are not required by all
servers. The set of required WHOIS++ system commands are listed in servers. The set of required Whois++ system commands are listed in
Table I. Details of the allowable search terms for the search command Table I. Valid search terms for the search command
are included in Table II. are described in Table II.
Each WHOIS++ command also allows the use of one or more controlling Each Whois++ command also allows the use of one or more controlling
constraints, when selected can be used to override defaults or constraints, which, when selected, are used to override defaults or
otherwise modify server behavior. There is a core set of constraints otherwise modify the server's behavior. There is a core set of
that must be supported by all conforming servers. These include constraints that must be supported by all conforming servers:
SEARCH (which controls the type of search performed), FORMAT (which SEARCH (which controls the type of search performed), FORMAT (which
determines the output format used) and MAXHITS (which determines the determines the output format used) and MAXHITS (which determines the
maximum number of matches that a search can return). maximum number of matches that a search can return). These required
constraints are summarized in Table III.
These required constraints are summarized in Table III.
An additional set of optional constraints are used to provide support An additional set of optional constraints are used to provide support
for different character sets, indicate the need and type of for different character sets, provide data for the authentication
authentication to perform on a transaction, and permit multiple scheme, and requesting multiple transactions during a single communications
transactions during a single communications session. These optional session. These optional constraints are listed in Table IV.
constraints are listed in Table IV.
It is possible, using the required COMMANDS and CONSTRAINTS system It is possible, using the required COMMANDS and CONSTRAINTS system
commands, to query any WHOIS++ server for its list of supported commands, to query any Whois++ server for its list of supported
commands and constraints. commands and constraints.
Please note that the line terminator is defined as a carriage
return and line feed (CR/LF) pair. Also, none of the commands or
constraints supported by Whois++ are case sensitive. For example,
the following are equivalent: HELP, Help, help, hElp.
Capitalization of all letters (e.g. HELP) is used only to improve
the legibility of this document. Finally, "attribute value" is
defined as "the value associated with an attribute".
2.2.1. System Commands 2.2.1. System Commands
System commands are commands to the server for information or to System commands are commands to the server for information or to
control its operation. These include commands to list the template control its operation. These include commands to list the template
types available from individual servers, to obtain a single blank types available from individual servers, to obtain a single blank
template of any available type, and commands to obtain the list of template of any available type, and commands to obtain the list of
valid commands and constraints supported on a server. valid commands and constraints supported on a server.
There are also commands to obtain the current version of the WHOIS++ There are also commands to obtain the current version of the Whois++
protocol supported, to access a simple help subsystem, to obtain a protocol supported, to access a simple help subsystem, to obtain a
brief description of the service (which is intended, among other brief description of the service provided by the Whois++
things, to support the automated registration of the service by server. The DESCRIBE command is intended, among other
yellow pages directory services). All of these commands are required things, to support the automated registration of the service in
from a conforming WHOIS++ server. yellow pages directory services. The required commands are listed
in Table I.
------------------------------------------------------------------------ ------------------------------------------------------------------------
Short Long Form Functionality Short Long Form Functionality
----- --------- ------------- ----- --------- -------------
COMMANDS [ ':' HOLD ] list valid WHOIS++ commands COMMANDS [ ':' HOLD ] List Whois++ commands
supported by this server supported by this server
CONSTRAINTS [ ':' HOLD ] List valid constraints CONSTRAINTS [ ':' HOLD ] List valid constraints
supported by this server supported by this server
DESCRIBE [ ':' HOLD ] Describe this server, DESCRIBE [ ':' HOLD ] Describe this server,
formating the response formating the response
using a standard using a standard
"Services" template SERVICES template
'?' HELP [<string> [':' <cnstrnts>]] System help, using a "Help" '?' HELP [<string> [':' (<othercnstrnts> / HOLD)
template 0*(';' (<otherconstraints> / HOLD))]]
Provide help specific to this
Whois++ server, using a
"Help" template
LIST [':' <cnstrnts>] List templates supported LIST [':' (<othercnstrnts> / HOLD)
by this system 0*(';' (<otherconstraints> / HOLD))]
List templates supported
by this server
POLLED-BY [ ':' HOLD ] List indexing servers POLLED-BY [ ':' HOLD ] List indexing servers
that are know to track that are known to poll
this server this server
POLLED-FOR [ ':' HOLD ] List information about POLLED-FOR [ ':' HOLD ] List information about
what this server is servers this server polls
tracking for
SHOW <string> [':' <cnstrnts>] Show contents of templates SHOW <string> [':' <cnstrnts>] Show contents of template
specified specified in <string>
VERSION [ ':' HOLD ] return current version of VERSION [ ':' HOLD ] Show the version of
the protocol supported. the protocol supported by
this server
Table I - Required WHOIS++ SYSTEM commands. Table I - Required Whois++ SYSTEM commands.
------------------------------------------------------------------------ ------------------------------------------------------------------------
Below follows a descriptions for each command. Examples of responses Below follows a descriptions for each command. Examples of responses
to each command is in Appendix C. to each command are provided in Appendix C.
2.2.1.1. The COMMANDS command 2.2.1.1. The COMMANDS command
The COMMANDS command returns a list of commands that the server The COMMANDS command returns a list of commands that the server
supports. The response is formatted as a FULL response. supports. The response is formatted as a FULL response.
2.2.1.2. The CONSTRAINTS command 2.2.1.2. The CONSTRAINTS command
The CONSTRAINTS command returns a list of constraints and the values The CONSTRAINTS command returns a list of both the constraints and
of those that the server supports. The response is formatted as a their values that the server supports. The response is formatted as a
FULL response, where every constraint is represented as a separate FULL response, where every constraint is represented as a separate
record. The template name for these records is CONSTRAINT. No record. The template name for these records is CONSTRAINT. No
attention is paid to handles. Each record has, as a minimum, the attention is paid to handles. Each record has, as a minimum, the
following two fields: following two attributes:
- "Constraint", which contains the attribute name described - - "Constraint", whose value is the constraint name
"Default", which shows the default value for this constraint. - "Default", which shows the default value for this constraint.
If the client is permitted to change the value of the constraint, If the client is permitted to change the value of the constraint,
there is also: there is also:
- "Range" field, which contains a list of values that this - "Range", which contains a list of values that this
server supports, as a comma separated list; Or, if the range server supports, as a comma separated list, or, if the range
is numerical, as a pair of numbers separated with a hyphen. is numerical, as a pair of numbers separated with a hyphen.
Note that, irrespective of whether a session is continued (with the HOLD
constraint) or not, constraints are set to the default value unless
explicitly changed with a constraint in each query.
2.2.1.3. The DESCRIBE command 2.2.1.3. The DESCRIBE command
The DESCRIBE command gives a brief description about the server in a The DESCRIBE command gives a brief description about the server in a
"Services" template. The result is formatted as a FULL response with "Services" template. The result is formatted as a FULL response with
as a minimum one field: as a minimum one attribute:
- "Text", which in a human readable form describes the service. - "Text", which describes the service in a form legible by human users.
2.2.1.4. The HELP command 2.2.1.4. The HELP command
The HELP command takes an optional argument as subject to get help The HELP command takes an optional argument which is the subject on
for. which to get help. The answer is formatted as a FULL format response.
2.2.1.5. The LIST command 2.2.1.5. The LIST command
The LIST command returns the name of the templates available on the The LIST command returns the name of the templates available on the
server. The answer is formatted FULL format response. server. The answer is formatted as a FULL format response.
2.2.1.6. The POLLED-BY command 2.2.1.6. The POLLED-BY command
The POLLED-BY command returns a list of servers and the templates and The POLLED-BY command returns a list of servers and the templates and
attribute names that those server polled as centroids from this attribute names that those servers polled as centroids from this
server. The format is in FULL format with two attributes, Template server. The format is in FULL format with two attributes, "Template"
and Field. Each of these is a list of names of the templates or and "Field", whose values are lists of the names of the polled
fields polled. An empty result means either that the server is not templates and fields, respectively. An empty result means either
polled by anyone, or that it doesn't support indexing. that the server is not polled by anyone, or that it doesn't support
indexing.
2.2.1.7. The POLLED-FOR command 2.2.1.7. The POLLED-FOR command
The POLLED-FOR command returns a list of servers that this server has The POLLED-FOR command returns a list of servers that this server has
polled, and the template and attribute names for each of those. The polled, and the template and attribute names for each of those. The
answer is in FULL format with two attributes, Template and Field. An answer is in FULL format with two attributes, Template and Field. An
empty result means either that the server is not polling anyone, or empty result means either that the server is not polling anyone, or
that it doesn't support indexing. that it doesn't support indexing.
2.2.1.8. The SHOW command 2.2.1.8. The SHOW command
The SHOW command takes a template name as argument and returns The SHOW command takes a template name as argument and returns
information about a specific template, formatted as a FULL response. information about that template, formatted as a FULL response.
The answer is formatted as a blank template with the requested name. The answer is formatted as a blank template with the requested name.
2.2.1.9. The VERSION command 2.2.1.9. The VERSION command
The output format is a FULL response containg a record with template The output format is a FULL response containg a record with template
name VERSION. The record must have attribute name "Version", which name VERSION. The record must have attribute name "Version", whose
value is "2.0" for this version of the protocol. The record may also value is "2.0" for this version of the protocol. The record may also
have the additional fields "Program-Name" and "Program-Version" which have the additional fields "Program-Name" and "Program-Version" which
gives information about the server implementation if the server so gives information about the server implementation if the server so
desires. desires.
If the server also supports the earlier version of the protocol, If the server also supports the earlier version of the protocol,
"1.0", two records are given back as a response to the VERSION "1.0", two records are given back as a response to the VERSION
command, one for each version supported. command, one for each version supported.
2.2.2. The Search Command 2.2.2. The SEARCH Command
A search command consists of one or more search terms, which might A SEARCH command comprises one required element and one optional
each have local constraints, followed by an optional colon with a set element. The first (required) element is a set of one or more search
of global search constraints. terms. The second (optional) element is a set of global constraints,
which modify or control the search. Each search term can have an
optional set of local constraints that apply only to that term.
Each attribute value in the WHOIS++ database is divided into one or Each attribute value in the Whois++ database is divided into one or
more words separated by whitespace. Each search term operates on more words separated by whitespace (see Appendix F for a definition
every word in the attribute value. of whitespace) . Each search term operates on every word in the attribute
value.
Two or more search terms have to be combined with boolean operators AND, Two or more search terms have to be combined with boolean operators AND,
OR or NOT. The operator AND has higher precedence than the operator OR, OR or NOT. The operator AND has higher precedence than the operator OR,
but this can be changed by the use of parentheses. but this can be changed by the use of parentheses.
Boolean operators operates on the separate result sets created Boolean operators function as follows for two search terms, A and
when doing searches according to each of the search terms. The operation B. Let A1 be the result set from the first search term and B1 be the
A AND B produces C which have all objects occuring in both A and B. result set from the second search. The operation A AND B returns the
The operation A OR B creates a result set of all objects in either hits in the intersection of sets A1 and B1. The operation A OR B
A or B etc. The NOT operator is in the same way specifying when operating returns the hits in the union of the sets A1 and B1. The operation
on result set A, all objects not in the set A. NOT A returns all possible results that are not in set A1. The
behaviour of the boolean operators can be generalized to N search
terms where N > 2. Note that NOT has a higher precedence than AND
or OR, so NOT A AND B returns the hits in B that are not in A.
Search constraints that apply to every search term are specified as Search constraints that apply to all search terms are specified as
global constraints. Local constraints override global constraints for global constraints. Local constraints override global constraints for
the search term they are bound to. The search terms and the global the search term they are bound to. The search terms and the global
constraints are separated with a colon (':'). Additional global constraints are separated with a colon (':'). Each additional global
constraints are appended to the end of the search command delimited constraint is appended to the end of the search command, and a
with a semicolon ';'. semicolon ';' is used as the delimiter between global constraints.
If different search constraints can not be fulfilled, or the If any of the search constraints can not be fulfilled, or if
combination of different search constraints is uncombinable, the several of the specified constraints are mutually exclusive, the
server may choose to ignore some constraints, but still do the search server ignores the constraints that can not be fulfilled and those
and return some records. that are mutually exclusive. The server performs the search using
only the remaining constraints and returns the corresponding set of
records.
The set of required constraints are summarized in Table III. The set The set of required constraints are listed in Table III. The set
of optional constraints are summarized in Table IV. of optional constraints are listed in Table IV.
As an option, the server may accept specifications for attributes for As an option, the server may accept specifications for attributes
either inclusion or exclusion from a reply. Thus, users could specify to be included or excluded from a reply. Thus, users could specify
-only- those attributes to return, or specific attributes to filter -only- those attributes to return, or specific attributes to filter
out, thus creating custom views. out, thus creating custom views.
2.2.2.1. Format of a Search Term 2.2.2.1. Format of a Search Term
Each search term consists of one of the following: Each search term consists of one of the following:
1) A search string, followed by an optional semicolon and set of 1) A search string, followed by an optional set of semicolon-
semicolon-separated local constraints. separated local constraints. If local constraints are
specified, they are separated from the search string by a
semicolon. This is noted as:
<value> [';' <constraint>]*
2) A search term specifier (as listed in Table II), followed by a 2) A search term specifier (as listed in Table II), followed by a
'=', followed by a search string, an optional semicolon and a '=', followed by a search string, an optional set of
set of semicolon-separate local constraints. semicolon-separated local constraints. If local constraints are
specified, they are separated from the search string by a
semicolon. This is noted as:
3) An abbreviated search term specifier, followed by a search <specifier> = <value> [';' <constraint>]*
string, followed by an optional semicolon and set of
semicolon-separated local constraints.
4) A combination of attribute name, followed by '=', followed by 3) An attribute name, followed by '=', followed by
a search string, followed by an optional semicolon and set of a search string, followed by an optional set of
semicolon-separate local constraints. semicolon-separate local constraints. If local constraints are
specified, they are separated from the search string by a
semicolon.
If no term identifier is provided, then the search will be applied to <attribute_name> = <value> [';' <constraint>]*
attribute values only. This corresponds to an identifier of VALUE.
(Note: A <constraint> is a valid local constraint specification.)
If no search term specifier is provided, then the search will be
applied to attribute values only. This corresponds to an identifier
of VALUE.
When the user specifies the search term using the form: When the user specifies the search term using the form:
"<attribute_name> = <value>" "<attribute_name> = <value>"
this is considered to be an ATTRIBUTE-VALUE search. this is considered to be an ATTRIBUTE-VALUE search.
For discussion of the system reply format, and selecting the For discussion of the system reply format, and selecting the
appropriate reply format, see section 2.4. appropriate reply format, see section 2.4.
skipping to change at line 804 skipping to change at line 832
Valid specifiers: Valid specifiers:
----------------- -----------------
Name Functionality Name Functionality
---- ------------- ---- -------------
HANDLE Confine search to handles. HANDLE Confine search to handles.
VALUE Confine search to attribute VALUE Confine search to attribute
values. values.
(Note: The name HANDLE can be replaced with the shortname '!') (Note: The specifier HANDLE= can be replaced with the shorthand '!')
Acceptable forms of a search specifier:
---------------------------------------
1) <value> [';' <constraint>]*
2) <specifier> = <value> [';' <constraint>]*
3) <shortname> <value> [';' <constraint>]*
4) <attribute_name> = <value> [';' <constraint>]*
(Note: A <constraint> is a valid local constraint specification.)
Table II - Valid search command term specifiers. Table II - Valid search command term specifiers.
------------------------------------------------------------------- -------------------------------------------------------------------
2.2.2.2. Format of a Search String 2.2.2.2. Format of a Search String
Special characters that need to be quoted are preceeded by a Special characters that need to be quoted are preceeded by a
backslash, '\'. backslash, '\'.
Special characters are space ' ', tab, equal sign '=', comma ',', Special characters are space ' ', tab, equal sign '=', comma ',',
colon ':', backslash '\', semicolon ';', asterisk '*', period '.', colon ':', backslash '\', semicolon ';', asterisk '*', period '.',
parenthesis '()', square brackets '[]', dollar sign '$' and parenthesis '()', square brackets '[]', dollar sign '$' and
circumflex '^'. circumflex '^'.
If the search term is given in some other character set than ISO- If the search term is given in some other character set than ISO-
8859-1, it must be specified by the constraint INCHARSET. 8859-1, it must be specified by the constraint INCHARSET.
2.3. WHOIS++ Constraints 2.3. Whois++ Constraints
Constraints are intended to be hints or recommendations to the server Constraints are intended to be hints or recommendations to the server
about how to process a command. They may also be used to override about how to process a command. They may also be used to override
default behaviour, such as requesting that a server not drop the default behaviour, such as requesting that a server not drop the
connection after performing a command. connection after performing a command.
Thus, a user might specify a search constraint as "SEARCH=exact", Thus, a user might specify a search constraint as "SEARCH=exact",
which means that the search engine is to perform an exact match which means that the search engine is to perform an exact match
search. It might also specify "LANGUAGE=Fr", which implies that the search. The user might also specify "LANGUAGE=Fr", which means that the
server should display the french versions of the attribute values, server should (if possible) display the French versions of the attribute
and if possible use french in fuzzy matches. It might also values, and if possible use French in fuzzy matches. The server should also
be able to issue system messages in French. issue system messages in French.
In general, contraints take the form "<constraintname>=<value>", with In general, constraints take the form "<constraintname>=<value>", where
<value> being one of a specified set of valid values. The notable <value> is one of a specified set of valid values. The notable
exception is "HOLD", which takes no argument. exception is "HOLD", which takes no argument.
All constraints can be used as a global constraint, but only a few All constraints can be used as a global constraint (i.e., on the
can be used as local. See tables IV and V for information of which whole query transaction). Only a few can be used as a constraint
local to a search term. See tables III and IV for information about which
constraints can be local. constraints can be local.
The CONSTRAINTS system command is used to list the search constraints The CONSTRAINTS system command is used to list the search constraints
supported by an individual server. supported by an individual server.
If a server cannot satisfy the specified constraint there will be a If a server cannot satisfy the specified constraint, the server should
mechanism for informing the user in the reply, using system messages. indicate this to the user through the use of system messages.
In such cases, the search is still performed, with the the server In such cases, the search is still performed, with the the server
ignoring unsupported constraints. ignoring unsupported constraints.
2.3.1. Required Constraints 2.3.1. Required Constraints
The following CONSTRAINTS must be supported in all conforming WHOIS++ The following CONSTRAINTS must be supported in all conforming Whois++
servers. servers.
------------------------------------------------------------------ ------------------------------------------------------------------
Format LOCAL/GLOBAL Format LOCAL/GLOBAL
------ ------------- ------ -------------
SEARCH= {exact | lstring } LOCAL/GLOBAL SEARCH= exact / lstring LOCAL/GLOBAL
FORMAT= {full | abridged | handle | summary } GLOBAL FORMAT= full / abridged / handle / summary GLOBAL
MAXHITS= { 1-<max-allowed> } GLOBAL MAXHITS= 1-<max-allowed> GLOBAL
Table III - Required WHOIS++ constraints. Table III - Required Whois++ constraints.
------------------------------------------------------------------ ------------------------------------------------------------------
2.3.2. Optional CONSTRAINTS 2.3.2. Optional CONSTRAINTS
The following CONSTRAINTS and constraint values are not required of a The following CONSTRAINTS and constraint values are not required of a
conforming WHOIS++ server, but may be supported. If supported, their conforming Whois++ server, but may be supported. If supported, their
names and supported values must be returned in the response to the names and supported values must be returned in the response to the
CONSTRAINTS command. CONSTRAINTS command.
--------------------------------------------------------------------- ---------------------------------------------------------------------
Format LOCAL/GLOBAL Format LOCAL/GLOBAL
------ ------------- ------ -------------
SEARCH= { regex | fuzzy | substring | <X-format> } LOCAL/GLOBAL SEARCH= regex / fuzzy / substring LOCAL/GLOBAL
CASE= { ignore | consider } LOCAL/GLOBAL CASE= ignore | consider LOCAL/GLOBAL
FORMAT= { server-to-ask | <X-format> } GLOBAL FORMAT= server-to-ask GLOBAL
MAXFULL= { 1-<max-allowed> } GLOBAL MAXFULL= 1-<max-allowed> GLOBAL
AUTHENTICATE= password GLOBAL AUTHENTICATE= password GLOBAL
NAME= <string> GLOBAL NAME= <string> GLOBAL
PASSWORD= <string> GLOBAL PASSWORD= <string> GLOBAL
INCHARSET= { us-ascii | iso-8859-* | INCHARSET= us-ascii / iso-8859-* /
UNICODE-1-1-UTF-8 | UNICODE-2-0-UTF-8} GLOBAL UNICODE-1-1-UTF-8 / UNICODE-2-0-UTF-8 GLOBAL
OUTCHARSET= { us-ascii | iso-8859-* | OUTCHARSET= us-ascii / iso-8859-* /
UNICODE-1-1-UTF-8 | UNICODE-2-0-UTF-8} GLOBAL UNICODE-1-1-UTF-8 / UNICODE-2-0-UTF-8 GLOBAL
LANGUAGE= <As defined in ISO 639:1988> GLOBAL LANGUAGE= <As defined in ISO 639:1988> GLOBAL
HOLD GLOBAL HOLD GLOBAL
IGNORE= {attributelist} GLOBAL IGNORE= <attributelist> GLOBAL
INCLUDE= {attributelist} GLOBAL INCLUDE= <attributelist> GLOBAL
Table IV - Optional WHOIS++ constraints. Table IV - Optional Whois++ constraints.
---------------------------------------------------------------------- ----------------------------------------------------------------------
2.3.2.1. The SEARCH Constraint 2.3.2.1. The SEARCH Constraint
The SEARCH constraint is used for specifying the method that is to be The SEARCH constraint is used for specifying the method that is to be
used for the search. The default method is "exact". Following is a used for the search. The default method is "exact". Following is a
definition of each search method. definition of each search method.
exact The search will succeed for a word that exactly exact The search will succeed for a word that exactly
matches the search string. matches the search string.
substring The search will succeed for a word that matches substring The search will succeed for a word that matches
a part of a word. a part of a word.
regex The search will succeed for a word when a regular regex The search will succeed for a word when a regular
expression matches the searched data. Regular expression matches the searched data. Regular
expression is built up by using constructions of expression is built up by using constructions of
'*', '.', '^', '$', and '[]'. For use of '*', '.', '^', '$', and '[]'. For use of
regular expressions see Appendix G. regular expressions see Appendix H.
fuzzy The search will succeed for words that matches the fuzzy The search will succeed for words that matches the
search string by using an algorithm designed to catch search string by using an algorithm designed to catch
closely related names with different spelling, e.g. closely related names with different spelling, e.g.
names with the same pronounciation. The server names with the same pronunciation. The server
chooses which algorithm to use, but it may vary chooses which algorithm to use, but it may vary
depending on template name, attribute name and depending on template name, attribute name and
language used (see Constraint Language above). language used (see Constraint Language above).
lstring The search will succed for words that begins lstring The search will succeed for words that begins
with the search string. with the search string.
2.3.2.2. The FORMAT Constraint 2.3.2.2. The FORMAT Constraint
The FORMAT constraint describes what format the result will be in. The FORMAT constraint describes what format the result will be in.
Default format is FULL. For a description of each format, see Server Default format is FULL. For a description of each format, see Server
Response Modes below. Response Modes below.
2.3.2.3. The MAXFULL Constraint 2.3.2.3. The MAXFULL Constraint
The MAXFULL constraint sets the limit of the number of matching The MAXFULL constraint sets the limit of the number of matching
records the server allows before it enforces SUMMARY responses. The records the server allows before it enforces SUMMARY responses. The
client may attempt to override this value by specifying another value client may attempt to override this value by specifying another value
to that constraint. Example: If, for privacy reasons, the server will to that constraint. Example: If, for privacy reasons, the server is to
return the response in SUMMARY format if the number of hits exceeds return the response in SUMMARY format if the number of hits exceeds
2, the MAXFULL constraint is set to 2 by the server. 2, the MAXFULL constraint is set to 2 by the server.
Regardless of what format the client did or did not ask for, the Regardless of what format the client asked for, the server will change the
server will change the response format to SUMMARY when the number of response format to SUMMARY when the number of matching records equals or
matching records equals or exceeds this value. exceeds this value.
2.3.2.4. The MAXHITS Constraint 2.3.2.4. The MAXHITS Constraint
The MAXHITS constraint sets the maximum number of records the client The MAXHITS constraint sets the maximum number of records returned to the
can get in a search respone. client in response to a query.
2.3.2.5. The CASE Constraint 2.3.2.5. The CASE Constraint
The CASE constraint defines if the search should be done case The CASE constraint defines if the search should be case
sensistive or not. Default value is to have case ignored. sensitive or not. Default value is to have case ignored.
2.3.2.6. The AUTHENTICATE Constraint 2.3.2.6. The AUTHENTICATE Constraint
The AUTHENTICATE constraint describes which authentication method to The AUTHENTICATE constraint describes which authentication scheme to
use when executing the search. By using a specific authentication use when executing the search. Depending on the authentication scheme
method, some other constraints might be needed which is specified by used, some other constraints may have to be specified. The authentication
the authentication method. scheme definition identifies which constraints it requires.
The only authentication method described in this document is The only authentication scheme described in this document is
"password", if used, also the two other constraints "name" and "password". If used, also the two other constraints "name" and
"password" need to be set. "password" need to be set.
2.3.2.7. The NAME Constraint 2.3.2.7. The NAME Constraint
The NAME constraint is only used together with some authentication The NAME constraint is only used together with some authentication
method named by the constraint "authenticate". The only use described scheme named by the constraint "authenticate".
in this document is by sending a username as a string of characters
which together with the string given as an argument to the "password" With the password authentication scheme, this is expected to be a string
constraint is sent to the server. The server can use that pair of of characters representing a username, for which the specified password
strings to do a simple authentication check, similar to the UNIX should be verified (i.e., similar to the UNIX login program).
login program.
2.3.2.8. The PASSWORD Constraint 2.3.2.8. The PASSWORD Constraint
The PASSWORD constraint is only used together with some The PASSWORD constraint is only used together with some
authentication method named by the constraint "authenticate". The authentication scheme named by the constraint "authenticate".
only use described in this document is by sending a password as a
string of characters which together with the string given as an The password authentication scheme requires that the password associated
argument to the "name" constraint is sent to the server. The server with the username be supplied by this constraint. The server
can use that pair of strings to do a simple authentication check, can use that pair of strings to do a simple authentication check,
similar tothe UNIX login program. similar tothe UNIX login program.
2.3.2.9. The LANGUAGE Constraint 2.3.2.9. The LANGUAGE Constraint
The LANGUAGE constraints is given to specify which attribute values The LANGUAGE constraint specifies the language in which the client
should be presented to the client. It can be used as an extra wishes to receive responses. It therefore specifies which attribute
information to the fuzzy matching search method, and it might values should be presented to the user (i.e., only those in the specified
also be used to tell the server to give the system responses language, or for which no language information is available).
in another language, although this ability should be handled by It can also be used as an extra information to the fuzzy matching search
method, and it might also be used to tell the server to give the system
responses in another language. This should preferably be handled by
the client. The language codes defined in RFC 1766 [ALVE95] should be the client. The language codes defined in RFC 1766 [ALVE95] should be
used as a value for the language constraint. In these, the case of used as a value for the language constraint. In these, the case of
the letters are insignigicant. the letters are insignificant.
If a record have attribute values in different languages, and no LANGUAGE If a record has attribute values in different languages, and no LANGUAGE
search constraint was given in the query, the switch between the search constraint was given in the query, the switch between the
different languages should be given in the response by the use different languages should be given in the response by the use
of system messages 601 which has one argument only, the name of the of system messages 601 which has one argument only, the name of the
language or one of the predefined strings "ANY" or "DEF". A block language or one of the predefined strings "ANY" or "DEF". A block
of alternative attribute values starts with a language definition of alternative attribute values starts with a language definition
like "% 601 SE". After the first language specification, zero or like "% 601 SE". After the first language specification, zero or
more language specifications can be given, each switching into the more language specifications can be given, each switching into the
desired language. When all specific languages have been tagged, the desired language. When all specific languages have been tagged, the
specification "% 601 DEF" can be used for specifying default attribute specification "% 601 DEF" can be used for specifying default attribute
values. A block of alternative attributes must end with "% 601 ANY". values. A block of alternative attributes must end with "% 601 ANY".
The following is an example of the use of the language messages: The following is an example of a response using the language messages:
# FULL USER LOCAL USER-DOE # FULL USER LOCAL USER-DOE
% 601 FR % 601 FR
Name: Monsieur John Doe Name: Monsieur John Doe
% 601 SV % 601 SV
Name: Herr John Doe Name: Herr John Doe
% 601 DEF % 601 DEF
Name: Mister John Doe Name: Mister John Doe
% 601 ANY % 601 ANY
Email: jdoe@doe.pp.se Email: jdoe@doe.pp.se
# END # END
The language specifications might not be specified by the server if the The language specifications may be suppressed by the server (using
client has explicitely, by using the global constraint LANGUAGE, asked the % 601 messages) if the client has explicitly, by using the global
for a specific language. constraint LANGUAGE, asked for a specific language.
2.3.2.10. The INCHARSET Constraint 2.3.2.10. The INCHARSET Constraint
The INCHARSET constraint tells the server in which character set the The INCHARSET constraint tells the server in which character set the
search string itself is given in. The default character set is ISO- search string itself is given. The default character set is ISO-
8859-1. 8859-1.
2.3.2.11. The OUTCHARSET Constraint 2.3.2.11. The OUTCHARSET Constraint
The OUTCHARSET constraint tells the server in which character set the The OUTCHARSET constraint tells the server in which character set the
search result is supposed to be given in. The default character set is search result is supposed to be given in. The default character set is
ISO-8859-1, but the server might choose something else if necessary. ISO-8859-1, but the server may choose something else.
2.3.2.12. The IGNORE Constraint 2.3.2.12. The IGNORE Constraint
The IGNORE constraint specifies which attributes to NOT include in The IGNORE constraint specifies which attributes NOT to include in
the result. All other attributes will be included (as if named the result. All other attributes will be included (as if named
explicitly by the "include" constraint). explicitly by the "include" constraint).
If an attribute is named both with the "include" and "ignore" If an attribute is named both with the "include" and "ignore"
constraint, the attribute is to be included in the result, but the constraint, the attribute is to be included in the result, but the
system message must be "% 205 Requested constraint not fulfilled". system message "% 112 Requested constraint not fulfilled" must be
sent.
2.3.2.13. The INCLUDE Constraint 2.3.2.13. The INCLUDE Constraint
The INCLUDE constraint specifies which attributes to include in the The INCLUDE constraint specifies which attributes to include in the
result. All other attributes will be excluded (as if named explicitly result. All other attributes will be excluded (as if named explicitly
by the "ignore" constraint). by the "ignore" constraint).
If an attribute is named both with the "include" and "ignore" If an attribute is named both with the "include" and "ignore"
constraint, the attribute is to be included in the result, but the constraint, the attribute is to be included in the result, but the
system message must be "% 205 Requested constraint not fulfilled". system message must be "% 112 Requested constraint not fulfilled".
2.3.2.14. The HOLD Constraint
The HOLD constraint requests that the server hold open the connection
after sending the response to the query. The server waits for another
user input string.
2.4. Server Response Modes 2.4. Server Response Modes
The grammar for Whois++ responses is given in Appendix G, and described
below.
There are currently a total of five different response modes possible There are currently a total of five different response modes possible
for WHOIS++ servers. These are FULL, ABRIDGED, HANDLE, SUMMARY and for Whois++ servers. These are FULL, ABRIDGED, HANDLE, SUMMARY and
SERVER-TO-ASK. The syntax of each output format is specified in more SERVER-TO-ASK. The syntax of each output format is specified in more
detail in the following section. detail in Appendix G.
1) A FULL format response provides the complete contents of a 1) A FULL format response provides the complete contents of a
template matching the specified query, including the template template matching the specified query, including the template
type, the server handle and an optional record handle. type, the server handle and an optional record handle.
2) An ABRIDGED format response provides a brief summary, including 2) An ABRIDGED format response provides a brief summary, including
(as a minimum) the server handle, the corresponding record handle (as a minimum) the server handle, the corresponding record handle
and relevant information for that template. and relevant information for that template.
3) A HANDLE format response returns a line with information about 3) A HANDLE format response returns a line with information about
the server handle and record handle for a record that matched the server handle and record handle for a record that matched
the specified query. the specified query.
4) A SUMMARY response provides only a brief summary of information 4) A SUMMARY response provides only a brief summary of information
the number of matches and the list of template types in which the the number of matches and the list of template types in which the
matches occured. matches occurred.
5) A SERVER-TO-ASK response only returns pointers to other index 5) A SERVER-TO-ASK response only returns pointers to other index
servers which might possibly be able to answer the specified servers which might possibly be able to answer the specified
query. query.
The server may respond with a null answer and may also respond with a The server may optionally respond with an empty result set and may also
null answer together with a correct system message to indicate that respond with an empty response together with a system message to indicate
the query was too complex. that the query was too complex for it to fulfill.
2.4.1. Default Responses 2.4.1. Default Responses
By default, a WHOIS++ server will provide FULL responses. This may be By default, a Whois++ server will provide FULL responses. This may be
changed by the client with the use of the global constraint "format". changed by the client with the use of the global constraint "format".
The server will not respond with more matches than the value The server will not respond with more matches than the value
specified with the global constraint "maxhits" in any response specified with the global constraint "maxhits" in any response
format. If the number of matches exceeds this value, the server will format. If the number of matches exceeds this value, the server will
issues the system message 110 (maxhits value exceeded), but will issues the system message 110 (maxhits value exceeded), but will
still show the responses, up to the number of the "maxhits" still show the responses, up to the number of the "maxhits"
constraint value. This mechanism will allow the server to hide the constraint value. This mechanism will allow the server to hide the
number of possible matches to a search command. number of possible matches to a search command.
The server response modes are summarized in Table V.
2.4.2. Format of Responses 2.4.2. Format of Responses
Each response consists of a numerical system generated message, which Each response consists of a numerical system generated message, which
can be tagged with text, followed by an optional formatted response can be tagged with text, followed by an optional formatted response
message, followed by a second system generated message. The formatted message, followed by a second system generated message. The formatted
response itself can include system messages, for example for switches in response itself can include system messages, for example for switches in
language. language.
That is: That is:
'%' <system messages> <nl> '%' <system messages> <nl>
[ <formatted response> ] [ <formatted response> ]
'%' <system messages> <nl> '%' <system messages> <nl>
If there are no matches to a query, the system is not required to If there are no matches to a query, the system is not required to
generate any output as a formatted response, although it must still generate any output as a formatted response, although it must still
generate system messages. generate system messages.
For information about the format for system messages, see Appendix E. For information about the standard text for system messages, see
Appendix E.
2.4.3. Syntax of a Formatted Response 2.4.3. Syntax of a Formatted Response
All formatted responses except for the HANDLE response, consists of a All formatted responses except for the HANDLE response, consist of a
response-specific START line, followed by an optional response- response-specific START line, followed by an optional response-
specific data section, followed by a TERMINATION line. The HANDLE specific data section, followed by a TERMINATION line. The HANDLE
response is different in that it only consists of a START line. It response is different in that it only consists of a START line. It
is permissible to insert any number of lines consisting solely of is permissible to insert any number of lines consisting solely of
newlines within a formatted response to improve readibility. CR/LF pairs within a formatted response to improve readability.
Each line shall be limited to no more than 81 characters, including Each line shall be limited to no more than 81 characters, including
the terminating newline. If a line (including the required leading the terminating CR/LF pair. If a line (including the required leading
single space) would exceed 81 characters, it is to be broken into single space) would exceed 81 characters, it must be broken into
lines of no more than 81 characters, with each continuation line lines of no more than 81 characters, with each continuation line
beginning with a "+" character in the first column instead of the beginning with a "+" character in the first column instead of the
leading character. leading character.
If an attribute value in a data section includes a line break, the If an attribute value in a data section includes a line break, the
line break must be replaced by a CR/LF pair and the following line line break must be replaced by a CR/LF pair and the following line
begin with a "-" character in the first column, instead of the begin with a "-" character in the first column, instead of the
leading character. The attribute name is not repeated on consecutive leading character. The attribute name is not repeated on consecutive
lines. lines.
A TERMINATION line consists of a line with a '#' in the first column, A TERMINATION line consists of a line with a '#' in the first column,
followed by one white space character (SPACE or TAB), followed by the followed by one space (ASCII 32) character, followed by the keyword END,
keyword END, followed by zero or more characters, followed by a followed by zero or more characters, followed by a CR/LF pair.
newline.
A response-specific section will be one of the following: A response-specific section will be one of the following:
1) FULL Format Response 1) FULL Format Response
2) ABRIDGED Format Response 2) ABRIDGED Format Response
3) HANDLE Format Response 3) HANDLE Format Response
4) SUMMARY Format Response 4) SUMMARY Format Response
5) SERVER-TO-ASK Format Response 5) SERVER-TO-ASK Format Response
The details of each are specified in the following sections:
2.4.3.1. A FULL format response 2.4.3.1. A FULL format response
A FULL format response consists of a series of responses, each A FULL format response consists of a series of responses, each
consisting of a START line, followed by the complete template consisting of a START line, followed by the complete template
information for the matching record and a TERMINATION line. information for the matching record and a TERMINATION line.
Each START line consists of a '#' in the first column, followed by Each START line consists of a '#' in the first column, followed by
one white space character, the word "FULL", a white space character, one space character, the word "FULL", a space character,
the name of the corresponding template type, one white space the name of the corresponding template type, one space
character, the server handle, a white space character, an optional character, the server handle, a space character, (optionally) the
handle for the record, and a terminating newline. handle for the record, and a terminating CR/LF pair.
The template information for the record will be returned as a series The template information for the record will be returned as a series
of lines consisting of a single space, followed by the corresponding of lines consisting of a single space, followed by the corresponding
line of the record. line of the record.
The line of the record shall consist of a single space and the The line of the record shall consist of a single space and the
attribute name followed by a ':', a single space, the value of that attribute name followed by a ':', a single space, the value of that
attribute, and a newline. attribute, and a CR/LF pair.
2.4.3.2. ABRIDGED Format Response 2.4.3.2. ABRIDGED Format Response
Each ABRIDGED format response consists of a START line, a single line Each ABRIDGED format response consists of a START line, a single line
excerpt of the template information from each matching record and a excerpt of the template information from each matching record and a
TERMINATION line. The excerpt information shall include information TERMINATION line. The excerpt information shall include information
that is relevant to the template type. that is relevant to the template type.
The START line consists of a '#' in the first column, followed by one The START line consists of a '#' in the first column, followed by one
white space character, the word "ABRIDGED", a white space character, space character, the word "ABRIDGED", a space character,
the name of the corresponding template type, a white space character, the name of the corresponding template type, a space character,
the server handle, a white space character, the handle for the the server handle, a space character, the handle for the
record, and a terminating newline. record, and a terminating CR/LF pair.
The abridged template information will be returned as a line, The abridged template information will be returned as a line,
consisting of a single space, followed by the abridged line of the consisting of a single space, followed by the abridged line of the
record and a newline pair. record and a CR/LF pair.
2.4.3.3. HANDLE Format Response 2.4.3.3. HANDLE Format Response
A HANDLE response consists of a single START line, which shall start A HANDLE response consists of a single START line, which shall start
with a '#' in the first column, followed by one white space with a '#' in the first column, followed by one space
character, the word "HANDLE", a white space character, the name of character, the word "HANDLE", a space character, the name of
the corresponding template, a white space character, the handle for the corresponding template, a space character, the handle for
the server, a white space character, the handle for that record, and the server, a space character, the handle for that record, and
a terminating newline. a terminating CR/LF pair.
2.4.3.4. SUMMARY Format Response 2.4.3.4. SUMMARY Format Response
A SUMMARY format response consists of a single set of responses, A SUMMARY format response consists of a single response,
consisting of a line listing the number of matches to the specified consisting of a line listing the number of matches to the specified
query, followed by a list of all template types which satisfied the query, optionally a count of referrals, followed by a list of all template
query at least once. types which satisfied the query at least once.
The START line shall begin with a '#' in the first column, be The START line shall begin with a '#' in the first column, be
followed by one white space character, the word "SUMMARY", a white followed by one white space character, the word "SUMMARY", a white
space character, the handle for the server, and a terminating space character, the handle for the server, and a terminating
newline. CR/LF pair.
The format of the attributes in the SUMMARY format follows the The format of the attributes in the SUMMARY format follows the
rules for the FULL template, with the attributes "matches", rules for the FULL template, with the attributes "matches",
"referrals" and "templates". "matches" and "templates" are "referrals" and "templates". "matches" and "templates" are
mandatory, "referrals" optional. mandatory, "referrals" optional.
The first line must begin with the string "matches:", be The first line must begin with the string "matches:", be
followed by a space and the number of responses to the query and followed by a space and the number of responses to the query and
terminated by a newline. terminated by a CR/LF pair.
The following line shall either begin with the string "templates: " The following line shall either begin with the string "templates: "
or the string "referrals: ". The string "templates: " are followed or the string "referrals: ". The string "templates: " are followed
by a newline separated list of the name of the template types by a CR/LF separated list of the name of the template types
which matched the query. Each line following the first which which matched the query. Each line following the first which
include the text "templates:" must begin with a '-' instead of include the text "templates:" must begin with a '-' instead of
a space. The string "referrals: " is followed by the number of a space. The string "referrals: " is followed by the number of
referrals included in the number of hits. referrals included in the number of hits.
2.4.3.5. SERVER-TO-ASK Response 2.4.3.5. SERVER-TO-ASK Response
A SERVER-TO-ASK response consists of information to the client about A SERVER-TO-ASK response consists of information to the client about
a server to contact next to resolve a query. If the server has a server to contact next to resolve a query. If the server has
pointers to more than one server, it will present additional SERVER- pointers to more than one server, it will present additional SERVER-
TO-ASK responses. TO-ASK responses.
The SERVER-TO-ASK response will consist of a START line and a number The SERVER-TO-ASK response will consist of a START line and a number
of lines with attribute-value pairs, separated by CRLF. Each line is of lines with attribute-value pairs, separated by CRLF. Each line is
indented with one space. The end of a SERVER-TO-ASK response is indented with one space. The end of a SERVER-TO-ASK response is
indicated with a TERMINATION line. indicated with a TERMINATION line.
Each START line consists of a '#' in the first column, followed by Each START line consists of a '#' in the first column, followed by
one white space character, the word "SERVER-TO-ASK", a white space one space character, the word "SERVER-TO-ASK", a space
character, the handle of the server and a terminating newline. character, the handle of the server and a terminating CR/LF pair.
1. "Server-Handle" - The server handle of the server pointed at. 1. "Server-Handle" - The server handle of the server pointed at.
(req.) (req.)
2. "Host-Name" - Hostname for the server pointed at. 2. "Host-Name" - Hostname for the server pointed at.
3. "Host-Port" - Portnumber for the server pointed at. 3. "Host-Port" - Portnumber for the server pointed at.
4. "Protocol" - The protocol to use when contacting this server. (opt.) 4. "Protocol" - The protocol to use when contacting this server. (opt.)
Other attributes may be present, depending on the index server. Other attributes may be present, depending on the index server.
The default protocol to use is Whois++. The default protocol to use is Whois++.
2.4.4. System Generated Messages 2.4.4. System Generated Messages
All system generated messages must begin with a '%' as the first All system generated messages must have a '%' as the first
character, a space as the second one, followed by a three digit character, a space as the second one, followed by a three digit
number, a space and an optional text message. The total length of the number, a space and an optional text message. The total length of the
line must be no more than 81 characters long, including the line must be no more than 81 characters long, including the
terminating CR LF pair. There is no limit to the number of system terminating CR/LF pair. There is no limit to the number of system
messages that may be generated. messages that may be generated.
The format for multiline replies requires that every line, except the The format for multiline replies requires that every line, except the
last, begin with "%", followed by space, the reply code, a hyphen, last, begin with "%", followed by space, the reply code, a hyphen,
and an optional text. The last line will begin with "%", followed by and an optional text. The last line will begin with "%", followed by
space, the reply code, a space and some optional text. space, the reply code, a space and some optional text.
System generated messages displayed before or after the formatted System generated messages displayed before or after the formatted
response section are expected to refer to operation of the system or response section are expected to refer to operation of the system or
refer to the entire query. System generated messages within the refer to the entire query. System generated messages within the
output of an individual record during a FULL reponse are expected to output of an individual record during a FULL response are expected to
refer to that record only, and could (for example) be used to refer to that record only, and could (for example) be used to
indicate problems with that record of the response. See Appendix E indicate problems with that record of the response. See Appendix E
for a description of system messages. for a description of system messages.
2.5. Compatibility with Older WHOIS Servers 2.5. Compatibility with Older WHOIS Servers
Note that this format, although potentially more verbose, is still in Note that this format, although potentially more verbose, is still in
a human readible form. Responses from older systems that do not a human readable form. Responses from older systems that do not
follow this format are still conformant, since their responses would follow this format are still conformant, since their responses would
be interpreted as being equivalent to optional text messages, without be interpreted as being equivalent to optional text messages, without
a formatted response. Clients written to this specification would a formatted response. Clients written to this specification would
display the responses as a advisory text message, where it would display the responses as a advisory text message, where it would
still be readible by the user. still be readable by the user.
3. Miscellaneous 3. Miscellaneous
3.1. Acknowledgements 3.1. Acknowledgements
The WHOIS++ effort began as an intensive brainstorming session at the This document has been through many iterations of refinement, with
contributions of different natures along the way. These acknowledgements
accrue.
The Whois++ effort began as an intensive brainstorming session at the
24th IETF, in Boston Massachusetts. Present at the birth, and 24th IETF, in Boston Massachusetts. Present at the birth, and
contributing ideas through this early phase, were (alphabetically) contributing ideas through this early phase, were (alphabetically)
Peter Deutsch, Alan Emtage, Jim Fullton, Joan Gargano, Brad Peter Deutsch, Alan Emtage, Jim Fullton, Joan Gargano, Brad
Passwaters, Simon Spero, and Chris Weider. Others who have since Passwaters, Simon Spero, and Chris Weider. Others who have since
helped shape this document with feedback and suggestions include helped shape this document with feedback and suggestions include
Roxana Bradescu, Patrik Faltstrom, Kevin Gamiel, Dan Kegel, Michael Roxana Bradescu, Patrik Faltstrom, Kevin Gamiel, Dan Kegel, Michael
Mealling, Mark Prior and Rickard Schoultz. Mealling, Mark Prior and Rickard Schoultz.
Version 2 of the protocol is based on input during the lifetime of Version 2 of the protocol is based on input during the lifetime of
version 1. Especially I have to mention Jeff Allen, Leslie Daigle, version 1. Special mention goes to Jeff Allen, Leslie Daigle,
and Philippe Boucher. During the polishing of the RFC for version 2, and Philippe Boucher. During the polishing of the RFC for version 2,
important input was given by Len Charest, Clarke Anderson and others important input was given by Len Charest, Clarke Anderson and others
in the ASID working group of the IETF. in the ASID working group of the IETF.
3.2 References Work in the European ROADS project provided the opportunity to test this
protocol specification from the point of view of developing a test suite.
The challenge was not only to provide AN implementation that satisfied the
document, but to build tools that would be able to respond to all
POSSIBLE responses that could be implemented from the spec. This then
lead to the contribution of some textual clarifications. Specific thanks
go to Bill Heelan and Philippe Boucher.
[ALL96] Allen J., "The Common Indexing Protocol (CIP)", 3.2 References
draft-ietf-find-new-cip-02.txt, Nov 1996.
[ALVE95] Alvestrand H., "Tags for the Identification of [ALVE95] Alvestrand H., "Tags for the Identification of
Languages", RFC 1766, UNINETT, March 1995. Languages", RFC 1766, UNINETT, March 1995.
[RFC822] Crocker, D., "Standard for the Format of ARPA Internet
Text Messages", RFC 822, August 1982.
[HARR85] Harrenstein K., Stahl M., and E. Feinler, [HARR85] Harrenstein K., Stahl M., and E. Feinler,
"NICNAME/WHOIS", RFC 954, SRI, October 1985. "NICNAME/WHOIS", RFC 954, SRI, October 1985.
[POST82] Postel J., "Simple Mail Transfer Protocol", STD 10,
RFC 821, USC/Information Sciences Institute,
August 1982.
[IIIR] Weider C., and P. Deutsch, "A Vision of an [IIIR] Weider C., and P. Deutsch, "A Vision of an
Integrated Internet Information Service", RFC 1727 Integrated Internet Information Service", RFC 1727
Bunyip Information Systems, Inc., December 1994. Bunyip Information Systems, Inc., December 1994.
[POST82] Postel J., "Simple Mail Transfer Protocol", STD 10, [WINDX] Weider, C., J. Fullton, and S. Spero, "Architecture of
RFC 821, USC/Information Sciences Institute, the Whois++ Index Service", RFC 1913, February 1996.
August 1982.
3.3. Authors Addresses 3.3. Authors Addresses
Patrik Faltstrom Patrik Faltstrom
Tele2 Tele2
Borgarfjordsgatan 16 Borgarfjordsgatan 16
BOX 62 BOX 62
194 64 Kista 194 64 Kista
SWEDEN SWEDEN
Email: paf@swip.net Email: paf@swip.net
Sima Newell
Bunyip Information Systems Inc.
310 Ste. Catherine St. W
Suite 300
Montreal, Quebec, CANADA
H2X 2A1
Email: sima@bunyip.com
Leslie L. Daigle
Bunyip Information Systems Inc.
310 Ste. Catherine St. W
Suite 300
Montreal, Quebec, CANADA
H2X 2A1
Email: leslie@bunyip.com
Appendix A - Some Sample Queries Appendix A - Some Sample Queries
author=leslie and template=user author=leslie and template=user
The result will consist of all records where attribute "author" The result will consist of all records where attribute "author"
matches "chris" with case ignored. Only USER templates will be matches "leslie" with case ignored. Only USER templates will be
searched. An example of a matching attribute is "Author=Leslie L. Daigle". searched. An example of a matching attribute is "Author=Leslie L. Daigle".
This is the typical case of search. This is the typical case of searching.
author=leslie and template=user:language=fr author=leslie and template=user:language=fr
The result will consist of the same records as above, but if The result will consist of the same records as above, but if
attributes are available in alternative languages, only the attributes are available in alternative languages, only the
ones in french will be displayed. This means either the ones which ones in French will be displayed. These are either the ones which
have explicitely french values, or the default language. have explicitly been tagged as having French values, or ones that
are tagged as being in the "DEF" (default) language.
schoultz and rick;search=lstring schoultz and rick;search=lstring
The result will consist of all records which have one attribute value The result will consist of all records which have one attribute value
matching "schoultz" exactly and one having "rick" as leading matching "schoultz" exactly (because the default search type is exact)
substring, both with case ignored. One example is "Name=Rickard and one attribute with "rick" as leading substring, both with case ignored.
Schoultz". One example is "Name=Rickard Schoultz".
value=phone;search=substring value=phone;search=substring
The result will consist of all records which have attribute values The result will consist of all records which have attribute values
matching *phone*, for example the record "Name=Acme telephone inc.", matching *phone*, for example the record "Name=Acme telephone inc.",
but will not match the attribute name "phone". (Since "value" term but will not match the attribute name "phone". (Since term specifier
specifier is the default, the search term could be "phone" as well as is "value" by default, the search term could just as well have been
"value=phone".) simply "phone").
ucdavis;search=substring and (gargano or joan):include=name,email ucdavis;search=substring and (gargano or joan):include=name,email
This search command will find records which have records containing This search command will find records which have records containing
the words "gargano" or "joan" somewhere in the record, and has the the words "gargano" or "joan" somewhere in the record, and has the
word "ucdavis" somewhere in a word. The result will only show the word "ucdavis" somewhere in a word. The result will only show the
"name" and "email" fields. "name" and "email" fields.
Appendix B - Some sample responses Appendix B - Some sample responses
skipping to change at line 1466 skipping to change at line 1523
-------------------- --------------------
3) HANDLE format responses: 3) HANDLE format responses:
# HANDLE USER SERVERHANDLE1 PD45 # HANDLE USER SERVERHANDLE1 PD45
# HANDLE USER SERVERHANDLE1 AE1 # HANDLE USER SERVERHANDLE1 AE1
# HANDLE SERVICES SERVERHANDLE1 WWW1 # HANDLE SERVICES SERVERHANDLE1 WWW1
-------------------- --------------------
4) A SUMMARY HANDLE format response: 4) A SUMMARY format response:
# SUMMARY SERVERHANDLE1 # SUMMARY SERVERHANDLE1
Matches: 35 Matches: 35
Referrals: 2 Referrals: 2
Templates: User Templates: User
-Services -Services
-Abstracts -Abstracts
# END # END
Appendix C - Sample responses to system commands Appendix C - Sample responses to system commands
skipping to change at line 1574 skipping to change at line 1631
CONSTRAINT: incharset CONSTRAINT: incharset
DEFAULT: ISO-8859-1 DEFAULT: ISO-8859-1
RANGE: ISO-8859-1, UNICODE-1-1-UTF8 RANGE: ISO-8859-1, UNICODE-1-1-UTF8
# END # END
# FULL CONSTRAINTS SERVERHANDLE1 # FULL CONSTRAINTS SERVERHANDLE1
CONSTRAINT: outcharset CONSTRAINT: outcharset
DEFAULT: ISO-8859-1 DEFAULT: ISO-8859-1
RANGE: ISO-8859-1, UNICODE-1-1-UTF8, HTML RANGE: ISO-8859-1, UNICODE-1-1-UTF8, HTML
# END # END
C.3 Response to the COMMANDS command C.7 Response to the COMMANDS command
# FULL COMMANDS SERVERHANDLE1 # FULL COMMANDS SERVERHANDLE1
Commands: commands Commands: commands
-constraints -constraints
-describe -describe
-help -help
-list -list
-polled-by -polled-by
-polled-for -polled-for
-show -show
-version -version
# END # END
Appendix D - Sample whois++ session Appendix D - Sample Whois++ session
Below is an example of a session between a client and a server. The Below is an example of a session between a client and a server. The
angle brackets to the left is not part of the communication, but is angle brackets to the left is not part of the communication, but is
just put there to denonte the direction of the communication between just put there to denote the direction of the communication between
the server or the client. Text appended to '>' means messages from the server or the client. Text appended to '>' means messages from
the server and '<' from the client. the server and '<' from the client.
Client connects to the server Client connects to the server
>% 220-Welcome to >% 220-Welcome to
>% 220-the whois++ server >% 220-the Whois++ server
>% 220 at ACME inc. >% 220 at ACME inc.
<name=Nick:hold <name=Nick:hold
>% 200 Command okay >% 200 Command okay
> >
># FULL USER ACME.COM NW1 ># FULL USER ACME.COM NW1
> name: Nick West > name: Nick West
> email: nick@acme.com > email: nick@acme.com
># END ># END
># SERVER-TO-ASK ACME.COM ># SERVER-TO-ASK ACME.COM
> Server-Handle: SUNETSE01 > Server-Handle: SUNETSE01
> Host-Name: whois.sunet.se > Host-Name: whois.sunet.se
> Host-Port: 7070 > Host-Port: 7070
># END ># END
># SERVER-TO-ASK ACME.COM ># SERVER-TO-ASK ACME.COM
> Server-Handle: KTHSE01 > Server-Handle: KTHSE01
># END ># END
>% 226 Tranfer complete >% 226 Transfer complete
<version <version
>% 200 Command okay >% 200 Command okay
># FULL VERSION ACME.COM ># FULL VERSION ACME.COM
> Version: 2.0 > Version: 2.0
># END ># END
>% 226 Tranfer complete >% 226 Transfer complete
>% 203 Bye >% 203 Bye
Server closes the connection Server closes the connection
In the example above, the client connected to a whois++ server and In the example above, the client connected to a Whois++ server and
queried for all records where the attribute "name" equals "Nick", and queried for all records where the attribute "name" equals "Nick", and
asked the server not to close the connection after the response by asked the server not to close the connection after the response by
using the global constraint "HOLD". using the global constraint "HOLD".
The server responds with one record and a pointer to two other The server responds with one record and a pointer to two other
servers that either holds records or pointers to other servers. servers that either holds records or pointers to other servers.
The client continues with asking for the servers version number The client continues with asking for the servers version number
without using the HOLD constraint. After responding with protocol without using the HOLD constraint. After responding with protocol
version, the server closes the connection. version, the server closes the connection.
skipping to change at line 1660 skipping to change at line 1717
6, immediately after the numeric response code in all lines, except 6, immediately after the numeric response code in all lines, except
the last one, where the space is used. the last one, where the space is used.
Example 1 Example 1
% 200 Command okay % 200 Command okay
Example 2 Example 2
% 220-Welcome to % 220-Welcome to
% 220-the whois++ server % 220-the Whois++ server
% 220 at ACME inc. % 220 at ACME inc.
The client is not expected to parse the text part of the response The client is not expected to parse the text part of the response
message except when receiving reply 600 or 601, in which case the message except when receiving reply 600 or 601, in which case the
text part is in the former case the name of a character set that text part is in the former case the name of a character set that
will be used by the server in the rest of the response, and in the will be used by the server in the rest of the response, and in the
latter case when it specifies what language the attribute value is in. latter case when it specifies what language the attribute value is in.
The valid values for characters sets is specified in the "characterset" The valid values for characters sets is specified in the "characterset"
list in the BNF listing in Appendix F. list in the grammar in Appendix F.
The theory of reply codes is described in Appendix E in STD 10, RFC The theory of reply codes is described in Appendix E in STD 10, RFC
821 [POST82]. 821 [POST82].
------------------------------------------------------------------------ ------------------------------------------------------------------------
List of system response codes List of system response codes
------------------------------ ------------------------------
110 Too many hits The number of matches exceeded 110 Too many hits The number of matches exceeded
the value specified by the the value specified by the
maxhits constraint. Server maxhits constraint. Server
will still reply with as many will still reply with as many
records as "maxhits" allows. records as "maxhits" allows.
111 Requested constraint not supported One or more constraints in 111 Requested constraint not supported One or more constraints in
query is not implemented, but query is not implemented, but
the search is still done. the search is still done.
112 Requested constraint not fullfilled One or more constraints in 112 Requested constraint not fulfilled One or more constraints in
query has unacceptable value query has unacceptable value
and was therefore not used, and was therefore not used,
but the search is still done. but the search is still done.
200 Command Ok Command accepted and executed. 200 Command Ok Command accepted (i.e., syntax
okay, will be executed).
The client must wait for a The client must wait for a
transaction end system message. transaction end system message.
201 Command Completed successfully Command accepted and executed. 201 Command Completed successfully Command accepted and executed.
203 Bye Server is closing connection 203 Bye Server is closing connection
220 Service Ready Greeting message. Server is 220 Service Ready Greeting message. Server is
accepting commands. accepting commands.
skipping to change at line 1723 skipping to change at line 1781
502 Search expression too complicated This message is sent when the 502 Search expression too complicated This message is sent when the
server is not able to resolve server is not able to resolve
a query (i.e. when a client a query (i.e. when a client
sent a regular expression that sent a regular expression that
is too deeply nested). is too deeply nested).
530 Authentication failed The authentication phase 530 Authentication failed The authentication phase
failed. failed.
600 <token> Subsequent attribute values 600 <token> Subsequent attribute values
are encoded in the charater are encoded in the character
set specified by <token>. set specified by <token>.
601 <token> Subsequent attribute values 601 <token> Subsequent attribute values
are in the language specified are in the language specified
by <token>. by <token>.
601 DEF Subsequent attribute values 601 DEF Subsequent attribute values
are default values, i.e. they are default values, i.e. they
should be used for all languages should be used for all languages
not specified by "601 <token>" not specified by "601 <token>"
since last "601 ANY" message. since last "601 ANY" message.
601 ANY Subsequent attribute values 601 ANY Subsequent attribute values
are for all languages. are for all languages.
Table V - System response codes Table V - System response codes
------------------------------------------------------------------------ ------------------------------------------------------------------------
Appendix F - The WHOIS++ BNF Grammar Appendix F - The Whois++ Input Grammar
The following grammar, which uses BNF-like notation as defined in [RFC822],
defines the set of acceptable input to a Whois++ server.
N.B.: All Whois++ command, constraint, and value literals are shown here in
lower case for simplicity. These literals are to be accepted in upper, lower,
or mixed case.
whois-command = ( system-command [":" "hold"] whois-command = ( system-command [":" "hold"]
/ terms [":" globalcnstrnts] ) NL / terms [":" globalcnstrnts] ) NL
system-command = "constraints" system-command = "constraints"
/ "describe" / "describe"
/ "commands" / "commands"
/ "polled-by" / "polled-by"
/ "polled-for" / "polled-for"
/ "version" / "version"
skipping to change at line 1825 skipping to change at line 1890
casevalue = "ignore" / "consider" casevalue = "ignore" / "consider"
auth-method = "password" auth-method = "password"
string = 0*char string = 0*char
attributename = 1*normalchar attributename = 1*normalchar
char = "\" specialchar / normalchar char = "\" specialchar / normalchar
normalchar = <Characters 0-255 (decimal) except specialchar> normalchar = <Characters 32 to 254(decimal) except specialchar>
specialchar = " " / <tab> / "=" / "," / ":" / ";" / "\" / specialchar = " " / <tab> / "=" / "," / ":" / ";" / "\" /
"*" / "." / "(" / ")" / "[" / "]" / "^" / "*" / "." / "(" / ")" / "[" / "]" / "^" /
"$" / "!" / "?" "$" / "!" / "?"
whitespace = 1*(" " / <tab> / <CR> / <LF> / "@")
digit = "0" / "1" / "2" / "3" / "4" / digit = "0" / "1" / "2" / "3" / "4" /
"5" / "6" / "7" / "8" / "9" "5" / "6" / "7" / "8" / "9"
NL = <CR LF (decimal 13 10)> NL = <CR LF (decimal 13 10)>
NOTE: Significant blanks must be escaped. The following NOTE: Blanks that are significant to a query must be escaped. The
characters, when significant to the query, may be preceded following characters, when significant to the query, may be preceded
and/or followed by a single blank: and/or followed by a single blank:
: ; , ( ) = ! : ; , ( ) = !
Appendix G - Description of Regular expressions Appendix G - The Whois++ Response Grammar
The regular expressions described in this section is the same as used The following grammar, which uses BNF-like notation as defined in [RFC822],
in many other applications and operating systems. It is though very defines the set of responses expected from a Whois++ server upon receipt of a
valid Whois++ query.
N.B.: All the literals supplied by the Whois++ server may be in upper, lower,
or mixed case. For clarity, they are shown here in upper case only.
server = goodmessage mnl output mnl endmessage onlynl
/ badmessage onlynl endmessage onlynl
output = full / abridged / summary / handle
full = 0*(full-record / server-to-ask)
abridged = 0*(abridged-record / server-to-ask)
summary = summary-record
handle = 0*(handle-record / server-to-ask)
full-record = "# FULL " template serverhandle localhandle nl
1*(fulldata nl)
"# END" nl
abridged-record = "# ABRIDGED " template serverhandle localhandle nl
abridgeddata nl
"# END" nl
summary-record = "# SUMMARY " serverhandle nl
summarydata nl
"# END" nl
handle-record = "# HANDLE " template serverhandle localhandle nl
server-to-ask = "# SERVER-TO-ASK " serverhandle nl
server-to-askdata nl
"# END" nl
fulldata = " " attributename ": " attributevalue
abridgeddata = " " 0*( attributevalue / tab )
summarydata = " Matches: " number nl
[" Referrals: " number nl]
" Templates: " template 0*( nl "-" template)
server-to-ask-data = " Server-Handle:" <serverhandle> <nl>
" Host-Name: " hostname nl
" Host-Port: " number nl
[" Protocol: " prot nl]
0*(" " sstring ": " sstring nl)
attributename = sstring
attributevalue = longstring
template = sstring
serverhandle = sstring
localhandle = sstring
hostname = sstring
prot = sstring
longstring = string 0*( nl ( "+" / "-" ) string )
string = 0*char
sstring = 0*schar
schar = <Characters 32-254 (decimal) except special-char>
char = <Characters 32-254 (decimal) except nl>
special-char = ":" / " " / tab / nl
tab = <TAB (decimal 9)>
mnl = 1*nl
nl = onlynl [ 1*(message onlynl) ]
onlynl = <CR LF (decimal 13 10)>
message = [1*( messagestart "-" string onlynl)]
messagestart " " string onlynl
messagestart = "% " digit digit digit
goodmessage = [1*( goodmessagestart "-" string onlynl)]
goodmessagestart " " string onlynl
goodmessagestart= "% 200"
messagestart = "% " digit digit digit
badmessage = [1*( badmessagestart "-" string onlynl)]
badmessagestart " " string onlynl
badmessagestart = "% 5" digit digit
endmessage = endmessageclose / endmessagecont
endmessageclose = [endmessagestart " " string onlynl]
byemessage
endmessagecont = endmessagestart " " string onlynl
endmessagestart = "% 226"
byemessage = byemessagestart " " string onlynl
endmessagestart = "% 203"
number = 1*( digit )
digit = "0" / "1" / "2" / "3" / "4" / "5" / "6" / "7" / "8" / "9"
Appendix H - Description of Regular expressions
The regular expressions described in this section are the same as used
in many other applications and operating systems. However, it is very
simple and does not include logical operators AND and OR. simple and does not include logical operators AND and OR.
Searches using regular expressions are always using substring Searches using regular expressions always use substring
matching except when the regular expression contains the characters matching except when the regular expression contains the characters
'^' or '$'. '^' or '$'.
Character Function Character Function
--------- -------- --------- --------
<any except those listed in this table> Matches itself <any except those listed in this table> Matches itself
. Matches any character . Matches any character
skipping to change at line 1873 skipping to change at line 2061
[a-c] Matches 'a', 'b' or 'c' [a-c] Matches 'a', 'b' or 'c'
^ Matches beginning of ^ Matches beginning of
a token a token
$ Matches end of a token $ Matches end of a token
Examples Examples
--------- ---------
String Matches Matches not String Matches Doesn't match
------- ------- ----------- ------- ------- -------------
hello xhelloy heello hello xhelloy heello
h.llo hello helio h.llo hello helio
h.*o hello helloa h.*o hello helloa
h[a-f]llo hello hgllo h[a-f]llo hello hgllo
^he.* hello ehello ^he.* hello ehello
.*lo$ hello helloo .*lo$ hello helloo
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