From: Pekka Riikonen Date: Mon, 21 Nov 2005 18:07:41 +0000 (+0000) Subject: Added. X-Git-Tag: 1.2.beta1~770 X-Git-Url: http://git.silcnet.org/gitweb/?p=runtime.git;a=commitdiff_plain;h=d60003d3019371d4ce834a6cbfbf41c257f5a5f7 Added. --- diff --git a/doc/draft-riikonen-presence-attrs-04.nroff b/doc/draft-riikonen-presence-attrs-04.nroff new file mode 100644 index 00000000..7e48104e --- /dev/null +++ b/doc/draft-riikonen-presence-attrs-04.nroff @@ -0,0 +1,680 @@ +.pl 10.0i +.po 0 +.ll 7.2i +.lt 7.2i +.nr LL 7.2i +.nr LT 7.2i +.ds LF Riikonen +.ds RF FORMFEED[Page %] +.ds CF +.ds LH Internet Draft +.ds RH XXXXX +.ds CH +.na +.hy 0 +.in 0 +.nf +Network Working Group P. Riikonen +Internet-Draft +draft-riikonen-presence-attrs-03.txt XXXx +Expires: XXX + +.in 3 + +.ce 2 +User Online Presence and Information Attributes + + +.ti 0 +Status of this Memo + +This document is an Internet-Draft and is in full conformance with +all provisions of Section 10 of RFC 2026. Internet-Drafts are +working documents of the Internet Engineering Task Force (IETF), its +areas, and its working groups. Note that other groups may also +distribute working documents as Internet-Drafts. + +Internet-Drafts are draft documents valid for a maximum of six months +and may be updated, replaced, or obsoleted by other documents at any +time. It is inappropriate to use Internet-Drafts as reference +material or to cite them other than as "work in progress." + +The list of current Internet-Drafts can be accessed at +http://www.ietf.org/ietf/1id-abstracts.txt + +The list of Internet-Draft Shadow Directories can be accessed at +http://www.ietf.org/shadow.html + +The distribution of this memo is unlimited. + + +.ti 0 +Abstract + +This document defines set of attributes that can represent the online +user's presence in a network, and to provide general information about +the user. The purpose is to provide a generic mechanism to share +online presence and status, and general information about the user +to be used in several kind of network protocols and applications. +These attributes could be used by for example chat and conferencing +protocols (such as Instant Message protocols), network games, and +other similar network protocols and applications that has online +users in a network. + + + + + + + +.ti 0 +Table of Contents + +.nf +1 Introduction .................................................. 2 + 1.1 Requirements Terminology .................................. 2 +2 Attributes Concept ............................................ 3 + 2.1 Requesting Attributes ..................................... 3 + 2.2 Replying Attributes ....................................... 3 + 2.3 Attribute Data Types ...................................... 4 + 2.4 Attribute Payload ......................................... 4 + 2.5 Attributes ................................................ 5 +3 Security Considerations ....................................... 11 +4 References .................................................... 12 +5 Author's Address .............................................. 13 +6 Full Copyright Statement ...................................... 13 + + +.ti 0 +1. Introduction + +This document defines set of attributes that can represent the online +user's presence in a network, and to provide general information about +the user. The purpose is to provide a generic mechanism to share +online presence and status, and general information about the user +to be used in several kind of network protocols and applications. +These attributes could be used by for example chat and conferencing +protocols (such as Instant Message protocols), network games, and +other similar network protocols and applications that has online +users in a network. + +This document does not define these attributes to be used in any +specific protocol, but assumes that they can be used generally in +any kind of online network protocol. Furthermore, the document +pays attention to special needs of various protocols, such as +mobile network protocols, which requires the attributes to be +both robust and compact. The attributes are also considered to be +easily implementable and for this reason a clear and robust structure +was chosen for the attributes. + +This document is strongly influenced by Wireless Village Initiative +where similar attributes are defined, and credits for the ideas are +due there. However, they are defined only in the context of the +Wireless Village, and the format of the attributes used is not +suitable for general purpose usage. + + +.ti 0 +1.1 Requirements Terminology + +The keywords MUST, MUST NOT, REQUIRED, SHOULD, SHOULD NOT, RECOMMENDED, +MAY, and OPTIONAL, when they appear in this document, are to be +interpreted as described in [RFC2119]. + + +.ti 0 +2 Attributes Concept + +Many network protocols needs a way to transfer and retrieve status +information about users in a network. For example, many chat and +conferencing protocols such as IRC, and all Instant Message (IM) +protocols, such as ICQ has a way to retrieve presence and status +information about the users in the network. This could be added to +several other kind of network protocols as well, and for this reason +a defined mechanism to provide these informations is needed. + +The attributes are usually requested by an entity in the network +from other entity, usually a user or end user's device in the network. +The recipient then replies to each of the requested attributes and +sends the reply to the requester. + +This document does not define the actual transport for requesting and +providing the replies to the requests, since this is irrelevant. +This document defines a payload for requesting, and providing the +information, but how the payload is transported is not defined in +this document. In a client-server network model the user requesting +attributes usually destine the request to a remote user and the +server relays the attributes to the remote user. It is also possible +that the concept is not user-to-user, but the server replies to the +requested attributes on behalf of the user. + + +.ti 0 +2.1 Requesting Attributes + +When an entity requests attributes from a user in the network, +it assembles a list of Attribute Payloads, and sets the requested +attribute value into the payload. Each requested attribute is a separate +Attribute Payload and they MUST be appended one after the other. The +requester need to understand that the recipient may not understand all +the requested attributes, and may not reply to all of the requested +attributes. The requester also need to understand that the recipient +may reply with additional attributes that were not requested. + + +.ti 0 +2.2 Replying Attributes + +When en entity receives the Attribute Payloads it parses them one after +the other. The entity can parse each of the Attribute Payload separately +since it knows the length of the current attribute; next attribute +begins after the current attribute ends. The entity then checks the +requested attribute and SHOULD reply either with valid value or with +an indication that the attribute is unsupported or unknown. It is +also possible to reply with additional attributes that were not +requested. + +When replying to the requested attributes the entity assembles a list +of Attribute Payloads, each including the attribute type and the +actual attribute data. + + +.ti 0 +2.3 Attribute Data Types + +This section defines basic data types that can appear in the attributes +in this document. + +All integer values are stored in the MSB first order. The size of the +integer is provided separately with the attribute. Integer is +represented as "integer" in this documentation. + +Strings MUST be UTF-8 [RFC2279] encoded, and include 2 bytes length +field indicating the length of the string. Hence, when "string" value +appears in this documentation it is encoded as: + +.in 6 +Length Type Value +2 bytes integer Length of String field +variable UTF-8 String +.in 3 + +If string is not present then the length field includes zero (0) +value. + +Boolean value is represented as "boolean" and its size is 1 byte. +Value 0x00 indicates false value and value 0x01 indicates true value. + + +.ti 0 +2.4 Attribute Payload + +The Attribute Payload is used to request an attribute, and to reply +to the requested attribute. One payload includes one attribute. + + +.in 5 +.nf + 1 2 3 + 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 ++-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +| Attribute | Attr Flags | Attribute Length | ++-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +| | +~ Attribute Data ~ +| | ++-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +.in 3 + +.ce +Figure 1: Attribute Payload + + +.in 6 +o Attribute (1 byte) - Indicates the attribute included in this + Attribute Payload. + +o Attribute Flags (1 byte) - Indicates the flags associated + with this attribute. The following flags are defined: + + 0x01 ATTRIBUTE_FLAG_INVALID + + The attribute value in Attribute Data is invalid, or + unknown. This may be set to indicate that a requested + attribute is not available, its value is unknown, or + sender does not understand it. + + 0x02 ATTRIBUTE_FLAG_VALID + + The attribute value is included in the Attribute Data. + + When sending this payload to request attributes this value + MUST be set to zero (0) value. When sending a reply to the + request this field MUST NOT include a zero (0) value. + +o Attribute Length (2 bytes) - Indicates the length of the + Attribute Data field, not including any other field. + +o Attribute Data (variable length) - The Attribute Data. + The contents of this field is attribute specific, defined + subsequently. +.in 3 + + +.ti 0 +2.5 Attributes + +The following values can appear in the Attribute field in the +Attribute Payload to indicate the content of the attribute. The +format of the attribute data is represented as length, type and +value. Example: + +.in 6 +Length Type Value +2 bytes integer Some integer value +variable string Some string +1 byte boolean Boolean value +.in 3 + +When sending multiple Attribute Payloads it is possible to include +multiple same attributes in the packet. + + +.in 6 +0 ATTRIBUTE_NONE + + This attribute is reserved and it is never sent. + + +1 ATTRIBUTE_USER_INFO + + This attribute includes general information about the user, their + name and contact information. The content of this attribute is + a VCard version 3.0 as defined in RFC 2426 [RFC2426] and RFC 2425 + [RFC2425]. Note that some of the information that VCard provides + can be also provided in the means of providing other attributes. + The rationale for this is that the VCard does not provide all the + information, or with the required precision that may be desired in + some applications. It is therefore RECOMMENDED that this attribute + would be used to provide only basic and constant user information, + such as name and contact information, but not online status + information. + + Length Type Value + variable VCard Basic user information + + +2 ATTRIBUTE_SERVICE + + This attribute indicates a service in the Internet that the user + is currently using or has logged in. It also shows when the user + started using the service, and how long user has been idle in the + service. The value of this attribute is as follows: + + Length Type Value + 4 bytes integer Service Port (IANA specified) + variable string Service Address + 1 byte boolean Online status. If this is set to + 0x01 (true) it means the user is online + in the service. Set to 0x00 (false) when + out of reach. + variable string Signon date and time, UTC date, format as + in ISO 8601 + 4 bytes integer Idle time + + +3 ATTRIBUTE_STATUS_MOOD + + This attribute indicates the mood of the user. It can indicate + whether the user is eager to participate in the network. The + value of this attribute is as follows: + + Length Type Value + 4 bytes integer Mood mask (values ORed together) + + The following mood values are defined: + + 0x00000000 MOOD_NORMAL No specific mood, normal mood + 0x00000001 MOOD_HAPPY The user feels happy + 0x00000002 MOOD_SAD The user feels sad + 0x00000004 MOOD_ANGRY The user feels angry + 0x00000008 MOOD_JEALOUS The user feels jealous + 0x00000010 MOOD_ASHAMED The user feels ashamed + 0x00000020 MOOD_INVINCIBLE The user feels invincible + 0x00000040 MOOD_INLOVE The user feels being in love + 0x00000080 MOOD_SLEEPY The user feels sleepy + 0x00000100 MOOD_BORED The user feels bored + 0x00000200 MOOD_EXCITED The user feels excited + 0x00000400 MOOD_ANXIOUS The user feels anxious + + +4 ATTRIBUTE_STATUS_FREETEXT + + This attribute includes the user's online status free text. It + can provide personal status as a text message. The contents of + this attribute is a UTF-8 encoded free text string. + + Length Type Value + variable string Free text status string + + +5 ATTRIBUTE_STATUS_MESSAGE + + This attribute includes the user's online status message. It + could provide for example a multi media message showing the status + of the user. The contents of this attribute is a MIME object, + which can be used to provide for example video, audio, image or + other similar status message. It could also provide a reference + to the message, for example an URL address. + + Length Type Value + variable MIME Status message as MIME object + + +6 ATTRIBUTE_PREFERRED_LANGUAGE + + This attribute indicates the preferred language to be used when + communicating. The encoding of this attribute is as follows: + + Length Type Value + variable string ISO 639-2/T three letter code + + +7 ATTRIBUTE_PREFERRED_CONTACT + + This attribute indicates the preferred contact methods. It can + indicate the method the user prefers when contacting. The value + of this attribute is as follows: + + Length Type Value + 4 bytes integer Contact mask (values ORed together) + + The following contact methods are defined: + + 0x00000000 CONTACT_NONE No specific preferred contact method + 0x00000001 CONTACT_EMAIL Email is preferred + 0x00000002 CONTACT_CALL Phone call is preferred + 0x00000004 CONTACT_PAGE Paging is preferred + 0x00000008 CONTACT_SMS SMS is preferred + 0x00000010 CONTACT_MMS MMS is preferred + 0x00000020 CONTACT_CHAT Chatting is preferred + 0x00000040 CONTACT_VIDEO Video conferencing is preferred + + +8 ATTRIBUTE_TIMEZONE + + This attribute can be used to provide the current local time for + the user. The contents of this attribute is a UTF-8 encoded + string and the format of the string is UTC time zone defined + in the ISO 8601. + + Length Type Value + variable string UTC date, format as in ISO 8601 + + Note that ATTRIBUTE_USER_INFO may also provide this information. + However it is RECOMMENDED that this attribute is used when + current time zone information is provided. + + +9 ATTRIBUTE_GEOLOCATION + + This attribute can be used to provide measured global location of + the user. How this information is gathered is out of scope of + this document. The attribute can provide latitude and longitude + lateral positions, but also a vertical position. A parameter + describing the accuracy of the information can also be provided. + + Length Type Value + variable string Longitude (ex. 31 17 14.321W) + variable string Latitude (ex. 12 11 21.2N) + variable string Altitude + variable string Accuracy in meters + + Note that ATTRIBUTE_USER_INFO may also provide this information, + however it does not have the vertical position, or the accuracy + parameter. It is RECOMMENDED that this attribute is used when + providing current global position information. + + +10 ATTRIBUTE_DEVICE_INFO + + This attribute includes information about the user's device. + The encoding of this attribute is as follows: + + Length Type Value + 4 bytes integer Device type + variable string Name of the device manufacturer + variable string Device version + variable string Device model + variable string Device language (ISO 639-2/T) + + The following Device types are defined: + + 0 DEVICE_COMPUTER Device is a computer + 1 DEVICE_MOBILE_PHONE Device is a mobile phone + 2 DEVICE_PDA Device is a PDA + 3 DEVICE_TERMINAL Device is a terminal + + +11 ATTRIBUTE_EXTENSION + + This attribute indicates that the attribute value is vendor, + application or service specific attribute extension. This field + MUST include a MIME object, which is the extension value. This + document does not specify any explicit MIME objects for this + attribute. + + Length Type Value + variable MIME Attribute extension as MIME object + + +12 ATTRIBUTE_USER_PUBLIC_KEY + + This attribute includes the user's public key or certificate. + As the public key and certificate format depends on which sort + of algorithm or certificate encoding user is using we need to + define a mechanism to differentiate the public key types from + each other. This document specifies the most common public keys + and certificates. This attribute can be used to deliver the + user's public key, and it MUST be present if also the + ATTRIBUTE_USER_DIGITAL_SIGNATURE is present. Note that the + recipient of this attribute SHOULD verify the public key from + a third party, for example from Certification Authority. If + there are more than one ATTRIBUTE_USER_PUBLIC_KEY attributes set + and ATTRIBUTE_USER_DIGITAL_SIGNATURE is also set, the digital + signature SHOULD be verifiable with the first set public key. + + Length Type Value + variable string Public key/certificate type + variable data Public key/certificate data + + The following public key/certificate types are defined: + + ssh-rsa SSH RSA public key [SSH-TRANS] + ssh-dss SSH DSS public key [SSH-TRANS] + silc-rsa SILC RSA public key [SILC1] + silc-dss SILC DSS public key [SILC1] + pgp-sign-rsa OpenPGP RSA certificate [RFC2440] + pgp-sign-dss OpenPGP DSS certificate [RFC2440] + x509v3-sign-rsa X.509 Version 3 RSA certificate [RFC2459] + x509v3-sign-dss X.509 Version 3 DSS certificate [RFC2459] + + Most of these public key/certificate types are equivalent to + the types specified for SSH protocol [SSH-TRANS] and are expected + to be officially assigned by IANA. + + The encoding of the public key/certificate data in the attribute + is done in the manner defined in their respective definitions. + + Note that these public keys are intended for signing. Some + certificates may have a key usage restrictions and same key cannot + be used for both encryption and signing. Therefore, the name + of the certificate type indicates if they are intended for + signing only. + + +13 ATTRIBUTE_SERVER_PUBLIC_KEY + + This attribute includes a third party server or authority public + key or CA certificate and MUST be present if the attribute + ATTRIBUTE_SERVER_DIGITAL_SIGNATURE is also present. The format + for this attribute is identical to the ATTRIBUTE_USER_PUBLIC_KEY + attribute. If there are more than one ATTRIBUTE_SERVER_PUBLIC_KEY + attributes set and ATTRIBUTE_SERVER_DIGITAL_SIGNATURE is also set, + the digital signature SHOULD be verifiable with the first set public + key. + + +14 ATTRIBUTE_USER_DIGITAL_SIGNATURE + + This attribute value includes digital signature of all Attribute + Payloads except this attribute. This signature can be provided by + the user. This attribute SHOULD be last attribute provided in the + reply so that it is easier for the receiver to compute the signature + data to be verified. The format and encoding of this attribute + depends on the public key or certificate used to produce the + signature. See the ATTRIBUTE_USER_PUBLIC_KEY for all public keys + and certificates that can be used to produce a signature. + + Length Type Value + variable data Digital signature data + + The encodings are as follows per public key/certificate type: + + ssh-rsa and ssh-dss Defined in [SSH-TRANS] + silc-rsa and silc-dss Defined in [SILC1] + pgp-sign-rsa and pgp-sign-dss Defined in [RFC2440] + x509v3-sign-rsa and x509v3-sign-dss Defined in [PKCS7] + + The procedure producing the signature and encoding it are done + in the manner defined in their respective definitions, see the + provided references. Also the hash function used with the + signature procedure is defined by the public key/certificate type. + + +15 ATTRIBUTE_SERVER_DIGITAL_SIGNATURE + + This attribute value includes digital signature of all Attribute + Payloads except this attribute, but including the attribute + ATTRIBUTE_USER_DIGITAL_SIGNATURE. This signature can be provided + by a third party server or an authority which has verified the + information provided by the user. How it verifies this information + is out of scope of this document, however it may base its + information to a previous registration information and current + online status of the user in a service. This attribute SHOULD be + last when provided, so that it is easier for the receiver to + compute the signature data to be verified. The format for this + attribute is identical to the ATTRIBUTE_USER_DIGITAL_SIGNATURE + attribute. + + +16 ATTRIBUTE_USER_ICON + + This attribute includes the user's icon or picture that can be + associated with the user in the application's user interface. + The attribute is a MIME object of which content MUST be one of + the MIME image media types. + + Length Type Value + variable MIME Icon as MIME image message +.in 3 + + +.ti 0 +3 Security Considerations + +The use of these attributes dictates whether the attributes need to +be secured or not. However, as the attributes are considered to provide +accurate status information about specific user, it is suggested that +the attributes would be secured. The attributes should be digitally +signed whenever it is possible. Attributes can also be encrypted +if it is provided by the protocol using the attributes. A third party, +like a server in the network, could also verify the information and provide +digital signature in case the information is accurate. + +Even though the attributes would be digitally signed by the sender of +the attributes, the information contained in the attribute may still +be incorrect. The third party server should not apply digital signature +unless it can verify every attribute. The receiver of the attributes +should also not trust that the information in fact is correct. + +However, it is possible that the context where these attributes are used +the attributes are provided by a party that can provide the accurate +information. For example a server in the network could reply to the +attributes on behalf of the actual user for some of the attributes. + + +.ti 0 +4 References + +[RFC2119] Bradner, S., "Key Words for use in RFCs to Indicate + Requirement Levels", BCP 14, RFC 2119, March 1997. + +[RFC2279] Yergeau, F., "UTF-8, a transformation format of ISO + 10646", RFC 2279, January 1998. + +[RFC2425] Howes, T., et al, "A MIME Content-Type for Directory + Information", RFC 2425, September 1998. + +[RFC2426] Dawson, F., et al, "vCard MIME Directory Profile", + RFC 2426, September 1998. + +[SILC1] Riikonen, P., "Secure Internet Live Conferencing (SILC), + Protocol Specification", Internet Draft, May 2002. + +[RFC2440] Callas, J., et al, "OpenPGP Message Format", RFC 2440, + November 1998. + +[RFC2459] Housley, R., et al, "Internet X.509 Public Key + Infrastructure, Certificate and CRL Profile", RFC 2459, + January 1999. + +[SSH-TRANS] Ylonen, T., et al, "SSH Transport Layer Protocol", + Internet Draft. + +[PKCS7] Kalinski, B., "PKCS #7: Cryptographic Message Syntax, + Version 1.5", RFC 2315, March 1998. + + + + +.ti 0 +5 Author's Address + +Pekka Riikonen +Snellmaninkatu 34 A 15 +70100 Kuopio +Finland + +EMail: priikone@iki.fi + + +.ti 0 +6 Full Copyright Statement + +Copyright (C) The Internet Society (2003). 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. +