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Network Working Group                                       R. HedbergRequest for Comments: 2378                             Umea UniversityCategory: Informational                                       P. Pomes                                                        QUALCOMM, Inc.                                                        September 1998The CCSO Nameserver (Ph) ArchitectureStatus of this Memo   This memo provides information for the Internet community.  It does   not specify an Internet standard of any kind.  Distribution of this   memo is unlimited.Copyright Notice   Copyright (C) The Internet Society (1998).  All Rights Reserved.Abstract   The Ph Nameserver from the Computing and Communications Services   Office (CCSO), University of Illinois at Urbana-Champaign has for   some time now been used by several organizations as their choice of   publicly available database for information about people as well as   other things.  This document provides a formal definition of the   client-server protocol.  The Ph service as specified in this document   is built around an information model, a client command language and   the server responses.1.  Overview1.1.  Basic Information Model   At its simplest the Ph database can be thought of as a computer-   resident "phone book".  However, it can be used to collect arbitrary   information about people, and in response to a query about an object   named in the database, return information about that entity.  It is   in short a nameserver for people and objects.  It was designed to   keep a relatively small amount of arbitrary information about a   relatively large number of people or things, and provide access to   that information over the Internet.  In order to structure the   information the manager of the database has to decide which views to   present of the real-world objects that are to be represented in the   database.  Each view is then composed of a number of fields and their   values.  To support this concept Ph has the notion of named   information, i.e., categorizing information into what are called   fields and assigning descriptive names to those fields.Hedberg & Pomes              Informational                      [Page 1]

RFC 2378         The CCSO Nameserver (Ph) Architecture    September 1998   Even if the database resides and is reachable from the Internet it is   local in the meaning that no server is supposed to be able to refer a   client to another server which might hold the wanted information.   However a server may contain a list of other Nameservers which can be   used by clients to query other Nameservers for information.1.1.1.  Fields   A field descriptor is associated with each field and is used to   describe the type and behavior of the field.  A field descriptor   includes the fieldname, the maximum length of information the field   can store before truncation, keywords describing the properties of   the field as well as free text describing what kind of information   the field is supposed to hold.   The keywords can be any of the following:   Always:   Forces the field's contents to be always printed in             addition to whatever fields specified by the query.   Any:      This field is always searched by queries. To be most             use ful, a field marked as Any should also have the Indexed             and Lookup keywords as well.   Change:   Can be changed by the owner of the entry.   Default:  Printed if no return clause is given in the query.   Encrypt:  Must be encrypted before transmission.   ForcePub: Viewable/searchable regardless of the content of the             suppress field   Indexed:  Fields that are kept track of in the database's index for             efficient lookups.  At least one indexed field must be             present in each query.   LocalPub: May be viewed by anyone in the "local" domain or address             space.  Fields with this keyword are completely invisible             outside of the "local" domain.  They will not be shown with             the fields command (section 3.3), and are disallowed in             query commands or return clauses (section 3.8).   Lookup:   May be used in the selection part of a query.  A Field             without this keyword may not be used to select entries.   NoMeta:   Wildcard searches are disallowed.Hedberg & Pomes              Informational                      [Page 2]

RFC 2378         The CCSO Nameserver (Ph) Architecture    September 1998   NoPeople: No entry of type "person" may include this field.   Private:  Field may be viewed by Heros (section 1.4) only.   Public:   May be viewed by anyone.  Fields not marked with this             keyword may only be viewed by the entry's owner or a Hero.   Sacred:   Changes to the field are prohibited except via non-network             invocations of the server, i.e., from a tty, file, or pipe.   Turn:     Users may turn off visibility of a field to everyone except             themselves and Heros by prefixing the field text with '*'.   Unique:   Any change to the field will be rejected if the change             causes the modified field to match the same field in any             other entry.1.1.2.  Character Sets   Historically Ph has been restricted to only handle printable   characters, that is characters with hexadecimal values between 0x20   and 0x7f.  Lately with the spreading of 8-bit clean Operating Systems   there is no reason to keep this limitation.   This document therefore proposes that ISO-8859-1 shall be regarded as   an alternative character set for Ph, the default still being US-   ASCII.   Clients that utilize ISO-8859-1 should request that the server return   ISO-8859-1 by using the "set"-command.   In the instance that values are stored using ISO-8859-1 and are to be   shown to a client expecting US-ASCII, the characters with character   codes outside of the US-ASCII range should be displayed in the   "Quoted-Printable" content-transfer-encoding form defined inRFC-2045   [MIME].   1.2.  Standardization issues   Each Nameserver manager is in essence free to name new fields to suit   the special needs of his/her organization.  But in order to make the   directory service useful outside of the organization it is   recommended that a core set of standard fields always should be   present.   Therefore this document defines a couple of standard collections of   fields (Appendix A).Hedberg & Pomes              Informational                      [Page 3]

RFC 2378         The CCSO Nameserver (Ph) Architecture    September 1998   Also note that the architecture makes no assumption about the search   and retrieval mechanisms used within individual servers.  Operators   are thereby free to use any kind of dedicated databases, fast   indexing software or even gateways to other directory services to   store and retrieve the information, if desired.   Ph simply functions as a known front-end, offering a simple data   model in addition to a well known port and simple query language.1.3.  Conventions Used in this Document   In examples, "C:" and "S:" indicate lines sent by the client and   server respectively.1.4.  Heros   For Ph a Hero is equivalent to a superuser or operator.  Being in   Hero mode means that some or all artificial limits are removed; full   Heros may change any field in any entry in the database, as well as   view as many entries as they wish.  Heros can also be limited to one   field of one other entry.  Hero mode is used mostly for   administrative purposes, delegation of group authority over selected   fields, and is controlled by the acl field.2.  Basic Operation   Initially, the server host starts the Ph service by listening on TCP   port 105.  When a client host wishes to make use of the service, it   establishes a TCP connection to the server host.  The client and the   Ph server then exchange commands and responses (respectively) until   the connection is closed or aborted.2.1.  Command syntax   Commands in Ph consist of a keyword optionally followed by zero or   more keywords or values, separated by spaces, tabs or newlines, and   followed by a carriage return-linefeed (CRLF) pair. A more thorough   description using BNF is given inAppendix C.   Values containing spaces, tabs or newlines must be enclosed in double   quotes ('"').  In addition the sequences "\n", "\t","\"" and "\\" may   be used to mean newline, tab, double quote and backslash,   respectively.   Keywords must be given in lower case; case in the values of fields is   preserved, although queries are not case-sensitive.Hedberg & Pomes              Informational                      [Page 4]

RFC 2378         The CCSO Nameserver (Ph) Architecture    September 19982.2.  Response syntax   Responses consist of a result code followed by additional information   possibly separated by entry index and/or field name and are   terminated by a CRLF pair.      result code:[entry index:][field name:]text   Responses to some commands might be multi-lined.  In these cases each   line in the response, except the last, has the appropriate result   code negated (prefaced with "-").  The last line then starts with the   appropriate result code without negation.  Each line must be   terminated by a CRLF pair.   If a particular command can apply to more than one entry, then the   multilined response must be so organized that all information   pertaining to each entry is returned on consecutive lines, and that   each of those lines must have one and the same entry index directly   following the resultcode.  The first entry index should be 1 and   incremented each time a new entry is referred to.      C: query hedberg return email name title      S: 102:There were 3 matches to your request.      S: -200:1:        email: canheg95@student.umu.se      S: -200:1:         name: Carl Johan Hedberg      S: -200:1:        title: Student      S: -200:2:        email: parheg95@student.umu.se      S: -200:2:         name: Par Hedberg      S: -200:2:        title: Student      S: -200:3:        email: Roland.Hedberg@umdac.umu.se      S: -200:3:         name: Roland Hedberg      S: -200:3:        title: Boss of the Network group      S: 200:Ok   Commands that can apply to more than one field must have the name of   the field to which the response applies directly following the entry   index.   The text of the response will be either an error message in human   readable format, or data from the Nameserver.  Whitespace (spaces or   tabs) may appear anywhere in the response, but the field name and   text columns if present must each begin with a whitespace character.   Since more than one specific piece of information may be manipulated   by a particular command, it is possible for parts of a command to   succeed, while other parts of the same command fail.  This situation   is handled as a single multi-line response with the result code   changing as appropriate.Hedberg & Pomes              Informational                      [Page 5]

RFC 2378         The CCSO Nameserver (Ph) Architecture    September 1998   As for FTP, the result codes are in the range 100-699 (or from -699   to -100 for multiline responses), where the leading digit has the   following significance:      1: In progress      2: Success      3: More information needed      4: Temporary failure; it may be worthwhile to try again.      5: Permanent failure      6: Phquery specific codes   Many commands generate more than one line of response; every client   should be prepared to deal with such continued responses.  Note that   a command is finished when and only when the result code on a   response line (treated as a signed integer) is greater than or equal   to 200.   Clients should assume that any numeric response, within the above   mentioned ranges, are valid.  Also note that the server is allowed to   send one or more lines with result codes between -199 - -100 (the   leading "-" indicates a continuation line) and 100 - 199, as status   information, before the actual results are transmitted.2.3.  Format of a search string   Matching is not sensitive to upper or lower case letters and is   normally done on a word-by-word basis. That is, both the query   expression and the entry information is broken up into words, and   individual words are compared using exact matching.  If the order of   the words is important in a query, then the query string can be   surrounded by '"' (double quotes), whereby the complete search string   is matched against the information in the Nameserver database.   Word delimiters are the following characters: <SPACE>, <TAB>, <NEW-   LINE>, ",", ";" and ":" .  These characters are not indexed and   should not be part of the search string.   However, special symbols, called "wildcard" characters, can be used   if the exact spelling is unknown.  The '*' (asterisk, 0x2A) is used   in place of zero or more characters, '+' (plus, 0x2B) in place of one   or more unknown characters, and '?' (question mark, 0x3F) can be used   when exactly one character is unknown.  If the unknown character can   be one of a limited set this can be specified by surrounding the set   with brackets, e.g., [ei] means that in that place an 'e' or an 'i'   would match.Hedberg & Pomes              Informational                      [Page 6]

RFC 2378         The CCSO Nameserver (Ph) Architecture    September 19983.  Commands3.1.  status   status   Prints the message of the day and the current status of the   nameserver.      C: status      S: 100:Qi server $Revision: 1.6 $      S: 100:Ph passwords may be obtained at CCSO Accounting,      S: 100:1420 Digital Computer Lab, between 8:30 and 5 Monday-Friday.      S: 100:Be sure to bring your U of I ID card.      S: 200:Database ready3.2.  siteinfo   siteinfo   Returns information about the servers site. Possible fields are   Version        Version information for the server.   Maildomain     The mail domain to use for phquery-type mail.   Mailfield      The field containing the specific email address.   Mailbox        Mandatory entry that names the field to use as                  maildrop.   Administrator  Guru in charge of service.   Passwords      Person in charge of ordinary password/change requests.   Authenticate   Authentication methods supported by the server,                  ordered in the site-preferred way.  Presently the                  following options are defined:                    1   attempt auto login                    2   allowed to be interactive if needed                    4   use ANSI X9.9 challenge/response                    8   use v4 Kerberos login                    16  use v5 Kerberos [KRB5] login                    32  use GSS-API [GSS-API] login                    64  use email login                    128 password encrypted response to challenge                    256 use clear-text password                    512 use HMAC [HMAC] with SHA-1 of challenge stringHedberg & Pomes              Informational                      [Page 7]

RFC 2378         The CCSO Nameserver (Ph) Architecture    September 1998   Example        C: siteinfo        S: -200:1:version:3.1        S: -200:2:maildomain:umu.se        S: -200:3:mailfield:alias        S: -200:4:mailbox:email        S: -200:5:administrator:roland.hedberg@umdac.umu.se        S: -200:6:passwords:roland.hedberg@umdac.umu.se        S: -200:7:authenticate:64:32:128        S: 200: Ok.   The mail fields in the siteinfo command direct how address   information stored in the Nameserver is to be used for delivering   mail.   The specific (username, host) pair to where a user's mail should be   sent for final delivery is stored in the field named by {mailbox}.   Phquery and like utilities will use this field.   To construct a useable email address from Nameserver information, the   algorithm below is followed:        if ({maildomain} is not null) then             address = (contents of {mailfield})@{maildomain}        else             address = (contents of {mailfield})   Some existing client software will not format email addresses   correctly if the value of {mailbox} is set to anything other than   "email" when {maildomain} is non-empty.   If {mailbox} is set to anything other than {email}, {maildomain} must   be reported empty by the siteinfo command.  Also reformatting of each   record's {mailfield} must be done by the server before reporting it   to the client.3.3.  fields   fields [field ...]   Without an argument, a list of all available field descriptors should   be delivered.  Any space-separated argument(s) restricts the list to   the named fields.  Fields marked with the "LocalPub" keyword (section1.1.1) should not be delivered outside of the local domain.Hedberg & Pomes              Informational                      [Page 8]

RFC 2378         The CCSO Nameserver (Ph) Architecture    September 1998   The output of the command consists of two lines describing each   field.  The first line defines the field in technical terms (max   length and field attributes), while the second line is a brief   description of what the field is intended to    hold.  The second   number of each response is the field id number.      C: fields      S: -200:6:alias:max 32 Indexed Lookup Public Default      S: -200:6:alias:Unique name for user.      S: -200:3:name:max 64 Indexed Lookup Public Default      S: -200:3:name:Fullname      S: -200:2:email:max 128 Lookup Public Default      S: -200:2:email:Account to receive electronic mail.      S: -200:16:other:max 256 Lookup Public Default Change      S: -200:16:other:Other info the user finds important.      S: -200:33:home_phone:max 60 Lookup Public Change Turn      S: -200:33:home_phone:Home telephone number.      S: 200:Ok.3.4.  id   id information   Enters the given information in the Nameserver's log.  This command   is used by the Ph client to enter the user id of the person running   it.3.5.  set   set [option[=value] ...]   Sets the named option for this nameserver session to a value.  The   default string "on" is used if no value is supplied.  Used without   arguments it return the settable options and their current value.   Some common options are   echo      If on, echo the client's commands back to the client.   limit     Changes that affect more than the specified number of                entries results in an error.   charset   Return responses to the client in the character set                specified.   verbose   If on, report interim progress messages to the client.   addonly   If on, change commands can only create fields in entries,                not modify them.   nolog     If on, disable logging.   external  If on, make Fields marked as "LocalPub" invisible.Hedberg & Pomes              Informational                      [Page 9]

RFC 2378         The CCSO Nameserver (Ph) Architecture    September 1998   Example      C: set verbose=off      S: 200:Done.      C: set      S: -200:echo:off      S: -200:limit:2      S: -200:charset:iso-8859-1      S: -200:verbose:off      S: -200:addonly:off      S: -200:nolog:off      S: -200:external:on      S: 200:Done.3.6.  login, logout, answer, clear, email, and xlogin3.6.1.  login   login [alias]   The "login" command allows client users to identify themselves to the   Nameserver. More specifically it identifies a client user with a   particular entry in the Nameserver and allows them to change fields   in that entry and possibly other entries.  It is also necessary to be   logged in to the Nameserver to view certain sensitive fields in the   user's own entry.   In order to use the "login" command the client must prompt the user   for their ph alias and password.  The client is then responsible for   (optionally) encrypting the password and sending it to the server.   This will be covered in sections3.6.3 (answer) and 3.6.4 (clear).      C: login foo      S: 301:,:P"_Y$ONU%"SDUQ6&^`ZZ'?*#Y`A_.Z/A>?@SH>*-3.6.2.  logout   logout   The "logout" command allows a user who is logged in to the Nameserver   to logout.      C: logout S: 200:Ok.Hedberg & Pomes              Informational                     [Page 10]

RFC 2378         The CCSO Nameserver (Ph) Architecture    September 19983.6.3.  answer   answer encrypted-response   In response to the login command, the Nameserver responds with a   random challenge string.  The Nameserver client encrypts the   challenge with the password supplied by the user, uuencodes the   result into US-ASCII, and returns the printable result in the   "answer" command:   C: login ppomes   S: 301:.%$&.D^67$*1?<.2S@DR:Z@M*)AV-<:4QM>#R>M*HT   C: answer M5K'F:NI(a?M?O2+-a9`48RA#ZF=L9)G)/XRS7Q^0>0@-R7X$WGb`50B]   S: 200:ppomes:Hi how are you?   The encryption algorithm is based on a three rotor Enigma engine.   There are known attacks on the security of this approach.   The answer command is also used to return method-specific responses   to the xlogin command (section 3.6.6).3.6.4.  clear   clear cleartext-password   The "clear" command can be used instead of the "answer" command to   complete a login sequence.  It's argument is the user's cleartext   password.  This command is supplied only to support those clients   that have not implemented one of the encryption engines used by the   "answer" command.  It's use is strongly discouraged.      C: login ppomes      S: 301:E=@Y&VW^_9YVI;D5.[EB0:B)9Z#_&X$:2)/eL$VJC87      C: clear MySecret      S: 200:ppomes:Hi how are you?3.6.5.  email   email local-userid   The "email" command can also be used instead of the "answer" command   to complete a login sequence.  The value of local-userid is the   user's login name on the local machine.  If all of the following   conditions are true, then the email command will be accepted by the   server:Hedberg & Pomes              Informational                     [Page 11]

RFC 2378         The CCSO Nameserver (Ph) Architecture    September 1998   1) The connection to the server originates on port 1023 or less on      the client.  Note: This is a system port.  Port 1023 is not      allocated to this use.   2) The canonical name of the client's host matches the right-hand      side of the email address of the requested alias specified in the      "login" command.   3) The "local-userid" matches the left-hand side of the email      address belonging to the requested alias.   This is a weak but convenient form of authentication.  Depending on   the information users are allowed to change about themselves and the   threat environment the server operates in, this method may be   appropriate.  Servers should take care to avoid DNS spoofing.3.6.6.  xlogin   xlogin option alias   Extended login command for GSS, Kerberos v4 and v5, ANSI X9.9 token   devices (e.g., SNK/4), etc. The option is one of the values returned   in the Authenticate field of the "siteinfo" command (section 3.2).   Alias is the user's alias.      C: xlogin 16 ppomes      S: 301:DoKrbLogin started; send Kerberos mutual authenticator.      C: answer MJa8QO1cJHYz2IdWyg7uhAnixVqgCZQBWr64ciXYku1ktdu....      S: 200:ppomes:Hi how are you?      C: xlogin 4 ppomes      S: 302:SNK Challenge "024142":      C: answer 82344338      S: 200:ppomes:Hi how are you?   The answer command returns the requested quantity, Kerberos   authenticator, X9.9 device response, etc.  Binary quantities are   first uuencoded into US-ASCII.3.7.  add   add field=value...   This command is used to add new entries to the database.  You must be   logged in and have full Hero privileges (section 1.4) to use "add".      C: add name="doe john" alias="j-doe"      S: 200:Ok.Hedberg & Pomes              Informational                     [Page 12]

RFC 2378         The CCSO Nameserver (Ph) Architecture    September 19983.8.  query   query [field=]value [field=value] . . . [return field1 [field2]]   If no field is specified together with a value then the field is   assumed to be "name" and/or "nickname".  When more than one field-   value specification are given in a query, entries matching all   specifications are returned (implicit AND).   It is possible to define which fields should be returned by adding a   "return" clause.  If no return clause is defined the Ph server will   return a default list of fields.  Typical default fields are "alias",   "name", "title", "email", "phone", "address", "department", "www",   and "other".  A return clause consists of the word "return" followed   by a list of fields or the word "all".  If the word "all" is used   then all viewable fields will be returned.      C: query name=doe name=john      S: 102:There was 1 match to your request.      S: -200:1:            alias: j-doe      S: -200:1:             name: doe john      S: 200:Ok.3.9.  delete   delete [field=]value...   This command is used to delete entire entries from the database.  You   must be logged in and have full Hero (section 1.4) privileges to use   "delete".   The arguments to the "delete" command are the same as the selection   part of a "query" command.  "Delete" finds all the entries that match   the argument(s) and deletes them.   The "delete" command obeys the Nameserver "limit" option, which can   be used to prevent deletion of more entries than intended.      C: delete name="doe john" alias="j-doe"      S: 200:1 entries deleted.3.10.  change   change [field=]value    [make|force] field="value"...   This command is used to change one or more fields in one or more   entries to the values specified.  The "change" command consists of   two clauses, the "change" clause and the "make" or "force" clause.Hedberg & Pomes              Informational                     [Page 13]

RFC 2378         The CCSO Nameserver (Ph) Architecture    September 1998   The "change" clause determines which entries will be affected by the   command.  It uses the same arguments as the selection clause of a   "query" command.  The "make" or "force" clause specifies which   field(s) will be changed and the new value(s) of the specified   field(s).  The "force" clause is only used to make non-encrypted   changes to fields marked "Encrypt".   You must be logged in to use "change".   The "change" command obeys the Nameserver "limit" option, which can   be used to prevent changing the field contents of more entries than   intended.      C: change alias=j-doe force password=NewSecret      S: 200:1 entry changed.      C: set limit=500      S: 200:Done.      C: change fax="(619) 555-1212" make fax="(760) 555-1212"      S: 200: 113 entries changed.3.11.  help   help    [{native|client} [topic ...]]   Prints help on the Nameserver or on specific clients.  If client is   specified, it should be a valid Nameserver client identifier, such as   "ph".  The client-specific help will first be searched for topic, and   then the native help will be searched.  If topic is omitted, a list   of all available help texts will be returned.  If "native" or client   are also omitted, a list of clients will be returned.C: help native 101-200:1:101:-200:1: The Nameserver echo option is set.  The text of this response is-200:1: the command you just gave, which has not (yet) been executed.200:Ok.3.12.  quit/exit/stop   quit   Terminates the session with the Nameserver and causes the client to   exit.      C: quit      S: 200:Bye!Hedberg & Pomes              Informational                     [Page 14]

RFC 2378         The CCSO Nameserver (Ph) Architecture    September 19984.  Security4.1.  Transport Layer   In the absence of encryption between client and server, all   Nameserver traffic is unsecure.  Kerberos v4, v5, and the GSS-API all   provide encryption mechanisms, however the Nameserver protocol does   not support the means to negotiate encryption between client and   server.  This implies that all traffic can be seen by other machines   having access to the network linking the client and server.   Furthermore clear-text traffic is subject to modification in transit   between client and server.  Possible ways of augmenting this would be   to use something like TLS [TLS] or IPSec [IPSEC].4.2.  Server Authentication   Unless one of the mutual authentication mechanisms is used, e.g.,   Kerberos 4/5 or GSS-API, there is no way to prove the identity of a   server.  Further, there is no mechanism to prove a given server is   authoritative for a set of information.4.3.  Secure User Authentication   The Ph protocol allows the negotiation of several authentication   protocols between client and server, some weak and some strong.  It   does not prohibit the use of cleartext passwords, something which   should be depreciated, but is useful when dealing with some clients.4.4.  Privacy and Access Lists   Directory services like the CCSO white pages server that contain   information on persons have to consider privacy issues.  This paper   describes one way of partitioning specific attributes from unwanted   access by designating them visible only to the "local" community,   visible only to the person connected with the information, or visible   only to the database administrator.Hedberg & Pomes              Informational                     [Page 15]

RFC 2378         The CCSO Nameserver (Ph) Architecture    September 19984.5.  References   [GSS-API] Linn, J., "Generic Security Service Application Program             Interface, Version 2",RFC 2078, January 1997.   [HMAC]    Krawczyk, H., Bellare, M., and R. Canetti, "HMAC: Keyed-             Hashing for Message Authentication",RFC 2104, February             1997.   [IPSEC]   Atkinson, R., "Security Architecture for the Internet             Protocol",RFC 1825, August 1995.   [KRB5]    Kohl, J., and C. Neuman, "The Kerberos Network             Authentication Service (V5)",RFC 1510, September 1993.   [TLS]     Dierks, T., and C. Allen, "The TLS Protocol,             Version 1.0", Work in Progress.   [MIME]    Freed, N., and N. Borenstein, "Multipurpose Internet Mail             Extensions, (MIME) Part One: Format of Internet Message             Bodies",RFC 2045, November 1996.5.  Miscellaneous5.1.  Authors' Addresses   Roland Hedberg   Umdac   Umea University   901 87 Umea   Sweden   EMail: Roland.Hedberg@umdac.umu.se   Paul Pomes   Qualcomm Inc   6455 Lusk Blvd   San Diego, CA   USA   EMail: ppomes@qualcomm.comHedberg & Pomes              Informational                     [Page 16]

RFC 2378         The CCSO Nameserver (Ph) Architecture    September 1998Appendix A   Default fields and suggested lengths connected to different object   types.   All entries:  Information common to all entries   type              64   name              256   address           128   proxy             32   password          32   type=phone:   Information found in a phonebook   phone             64   fax               64   type=person:  Information about a human being   alias             32   forename          64   surname           64   group             32   email             128   public_key        4096   nickname          128   www               256   acl               128   type=staff:   Information about an employee   empno             16   department        64   supervisor        64   secretary         64   office_location   128   office_address    128   office_phone      64   title             64   pager             64   hours             128   type=unit:   Information about an organizational unit   email             128   www               256   public_key        4096Hedberg & Pomes              Informational                     [Page 17]

RFC 2378         The CCSO Nameserver (Ph) Architecture    September 1998Appendix B   Result codes   100 In progress (general).   101 Echo of current command.   102 Count of number of matches to query.   103 No hostname found for IP address.   200 Success (general).   201 Database ready, but read-only.   300 More information (general).   301 Encrypt this string.   302 Print this prompt.   400 Temporary error (general).   401 Internal database error.   402 Lock not obtained within timeout period.   403 Login would have been OK, but database read-only   475 Database unavailable; try later.   500 Permanent error (general).   501 No matches to query.   502 Too many matches to query.   503 Not authorized for requested information.   504 Not authorized for requested search criteria.   505 Not authorized to change requested field.   506 Request refused; must be logged in to execute.   507 Field does not exist.   508 Field is not present in requested entry.   509 Alias already in use.   510 Not authorized to change this entry.   511 Not authorized to add entries.   512 Illegal value.   513 Unknown option.   514 Unknown command.   515 No indexed field in query.   516 No authorization for request.   517 Operation failed because database is read-only.   518 To many entries selected by change command.   520 CPU usage limit exceeded.   521 Change command would have overridden existing field,   and the "addonly" option is on.   522 Attempt to view "Encrypted" field.   523 Expecting "answer" or "clear".   524 Names of help topics may not contain "/".   525 Email authentication failed   526 Host name address not found in DNS   527 Reverse DNS lookup does not match forward DNS lookup   528 General Kerberos database error.   529 Selected authentication method not availableHedberg & Pomes              Informational                     [Page 18]

RFC 2378         The CCSO Nameserver (Ph) Architecture    September 1998   590 Remote queries not allowed.   598 Command unknown.   599 Syntax error.   600 Ambiguous or multiple matchHedberg & Pomes              Informational                     [Page 19]

RFC 2378         The CCSO Nameserver (Ph) Architecture    September 1998Appendix  C   Description of the client command language using the augmented   Backus-Naur Form (RFC822).   response = code [index] [field] text CRLF   code     = [-] LDIG 2DIGIT ":"   index    = number ":"   field    = 1*SPACE attribute ":" 1*SPACE   text     = 1*( CHAR / LWSP-char )   command     = ph-command CRLF   ph-command  =  "status" / a-command / oa-command   ph-command  =/ av-command / answer-command / query-command   ph-command  =/ delete-command / change-command / "help" / quit-command   a-command       = ("siteinfo"/"fields"/"id"/"login"/"help"/"email"/              "clear") [attribute]   oa-command      = ("xlogin") number attribute   av-command      = ("set"/"add"/"make") 1*attribute-value   answer-command  = ("answer") 1*printable   query-command   = ("query"/"ph") 1*selection ["return" 1*attribute]   quit-command    = "quit" / "exit" / "stop"   change-command  = "change" 1*selection make 1*attribute-value   delete-command  = "delete" selection   selection       = value / attribute-value   attribute-value = attribute "=" value   value           = 1*(cstring / quoted-string / set)   cstring         = 1*( ALPHA / DIGIT / S_SPEC / set / quoted-pair )   attribute       = 1*( ALPHA / DIGIT / "_" / "-" )   number          = 1*(DIGIT)   quoted-string   = <"> 1*(qtext/quoted-pair) <">   quoted-pair  =  "\" CHAR   qtext        = 1*( CHAR / CR / SPEC1 / DELIMIT1 / DELIMIT2 / LWS )   set          = '[' 1*(ALPHA/DIGIT) ']'   LWSP-char    = SPACE / HTAB   LWS          = 1*([CRLF] (LWSP-char))   CRLF         = CR LFHedberg & Pomes              Informational                     [Page 20]

RFC 2378         The CCSO Nameserver (Ph) Architecture    September 1998   S_SPEC       = '*'/'+'/'?'   SPEC1        = "=" / "*" / "?" / "+" / "[" / "]"   SPEC2        = "\" / """   DELIMIT1     = SPACE / HTAB / LF   DELIMIT2     = "," / ";" / ":"   PRINTABLE    = %d32..%d126   CTL          = %d0..%d31 / %d127..%d160   ALPHA        = %d65..%d90 / %d97..%d122   DIGIT        = %d48..%d57   LDIG         = %d49..%d54   SPACE        = %d32   SEP          = (CR LF) / LF   CR           = %d13   LF           = %d10   HTAB         = %d9   CHAR         = %d33..%d126 / %d160..%d255   OTHER        = "(" / ")" / "-" / "." / "/"          "@" / "$" / "_" / "!" / "~" /          "'" / "#" / "&" / "<" / ">" /          "^" / "`" / "{" / "|" / "}"Hedberg & Pomes              Informational                     [Page 21]

RFC 2378         The CCSO Nameserver (Ph) Architecture    September 1998Full Copyright Statement   Copyright (C) The Internet Society (1998).  All Rights Reserved.   This document and translations of it may be copied and furnished to   others, and derivative works that comment on or otherwise explain it   or assist in its implementation may be prepared, copied, published   and distributed, in whole or in part, without restriction of any   kind, provided that the above copyright notice and this paragraph are   included on all such copies and derivative works.  However, this   document itself may not be modified in any way, such as by removing   the copyright notice or references to the Internet Society or other   Internet organizations, except as needed for the purpose of   developing Internet standards in which case the procedures for   copyrights defined in the Internet Standards process must be   followed, or as required to translate it into languages other than   English.   The limited permissions granted above are perpetual and will not be   revoked by the Internet Society or its successors or assigns.   This document and the information contained herein is provided on an   "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING   TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING   BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION   HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.Hedberg & Pomes              Informational                     [Page 22]