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diff --git a/spec/zot.txt b/spec/zot.txt deleted file mode 100644 index 2c3bbb180..000000000 --- a/spec/zot.txt +++ /dev/null @@ -1,362 +0,0 @@ -This is the Zot! social communications protocol. - -Specification revision: 1 -2 October 2011 - -Mike Macgirvin -This specification is public domain. - -Zot is a framework for secure delivery of messages on the web based on -webfinger and encapsulating salmon. - -First read the salmon and salmon magic envelope specifications. Zot also -makes use of webfinger and ActivityStreams and several concepts from RFC822 -(email). Zot encompasses the zot delivery framework and the zid remote -access protocol. - -The current specification revision (1) is frozen until a reference -implementation is available. After that, any protocol changes will require a -change to the revision number. - -**************** -* Zot delivery * -**************** - -Format of a zot wrapper. This completely encapsulates a salmon magic envelope -and provides privacy protection, while defining a delivery envelope - a -concept familiar to email systems. All addresses in zot are webfinger -resolvable addresses containing zot endpoints and salmon public keys (zot -is a superset of salmon). - - -<?xml version='1.0' encoding='UTF-8'?> -<zot:msg xmlns:zot='http://purl.org/zot/1.0'> - <zot:key>((key))</zot:key> - <zot:iv>((iv))</zot:iv> - <zot:env_key>((env_key))</zot:env_key> - <zot:env_iv>((env_iv))</zot:env_iv> - <zot:env>((envelope))</zot:env> - <zot:sig key_id="xxx">((sender signature))</zot:sig> - <zot:alg>AES-256-CBC</zot:alg> - <zot:data type='application/magic-envelope+xml'>((salmon))</zot:data> -</zot:msg> - - -zot:key -******* - -A suitable randomly generated encyption key of length 32 octets for encrypting -the salmon packet. This is then encrypted with the sender's private key and -base64url encoded. - -zot:iv -****** - -A suitable randomly generated initialisation vector of length 16 octets for -encrypting the salmon packet. This is then encrypted with the sender's private -key and base64url encoded. - -zot:env_key -*********** - -A suitable randomly generated encyption key of length 32 octets for encrypting -the envelope. This is then encrypted with the recipient's public key and -base64url encoded. For bulk deliveries, it is encrypted with the site bulk -delivery public key. - - -zot:env_iv -********** - -A suitable randomly generated initialisation vector of length 16 octets for -encrypting the envelope. This is then encrypted with the recipient's public -key and base64url encoded. For bulk deliveries, it is encrypted with the site -bulk delivery public key. - - -zot:env -******* - -This consists of RFC822-style header fields representing the sender and -recipient(s). Line lengths have no defined limit and RFC822 continuation -lines are not supported. If an inbound server is not able to process an -envelope or post due to size constraints, it SHOULD return a -"413 Entity too large" HTTP response. - -Example: - -Z-From: zot:bob@example.com -Z-Sender: zot:bob@example.com -Z-To: zot:alice@example.com - -Both "Z-From:" and "Z-Sender:" MUST be provided, and represent a single -webfinger address of the author and sender respectively. The webfinger -address for the From address MUST contain a discoverable salmon public key -which is needed to verify the enclosed salmon data. Sender is used to indicate -the webfinger identity responsible for transmitting this message. From -indicates the message author. - -In web-based social systems, a reply to a message SHOULD be conveyed to all of -the original message participants. Only the author of the original message -may know all the recipients (such as those contained in Bcc: elements). The -author of a message always provides 'From'. They MUST duplicate this -information as 'Sender' when posting a followup message. - -A reply to a given message MUST be sent to the From address of the original -post, and MAY be sent to any additional addresses in the recipient list. The -original post author MUST send the reply to all known recipients of the -original message, with their webfinger identity as Sender, and the -comment/reply author as From. - -Receiving agents SHOULD validate the From identity as the signer of the salmon -magic envelope, and MAY reject it. They SHOULD also verify the Sender signature -of the zot packet if it is different than the salmon signature. They MAY -reject the message if the Sender is not allowed in their "friend list", or if -they do not have a suitable relationship with the Sender, or if either -signature fails to validate. Rejected messages for one of these reasons SHOULD -be indicated with a "400 Bad Request" HTTP response. - - -Z-To: * - -indicates a public message with no specifically enumerated recipients. - -The fields Z-To: and/or Z-Bcc: MAY be present. At least one recipient field -MUST be present. - -Z-To: zot:bob@example.com, zot:alice@example.com, mailto:dave@example.com -Z-Bcc: zot:https://example.com/profile/richard - -are valid entries. Adresses are comma separated and individual entries MUST NOT -contain commas. There MAY be any number of ASCII space characters between -entries for legibility. Header lines are terminated with a linefeed character -(ASCII 0x0A). - -This specification provides the following protocol address prefixes -for use in Z-To: or Z-Bcc: elements: - -zot: - normal zot delivery using webfinger or LRDD resolvable address -dfrn: - legacy DFRN mode delivery using webfinger or LRDD resovable address -ostatus: - normal OStatus delivery using webfinger or LRDD resovable address -diaspora: - Diaspora network delivery using webfinger address -facebook: - Facebook profile page URL -twitter: - Twitter personal page URL without AJAX '#!' fragment -mailto: - email RFC822/ESMTP address - -Examples: - -twitter:http://twitter.com/bjensen -facebook:http://facebook.com/profile.php?id=000000001 - -Foreign protocol addresses which have not been defined in this specification -or future revisions of this specification and which are unknown to the -recipient delivery process MAY be ignored. - -In cases where an address may contain either a webfinger or LRDD address, the -webfinger address SHOULD be used preferentially. - - -Z-Bcc: -****** - -The Z-Bcc element may contain one or more addresses which are hidden from end -user presentation. A zot receiving system MUST NOT store or allow for -the display of the Bcc information. Implementations which require extreme -privacy SHOULD send individual posts to each of the Bcc: recipients containing -only a single address. They MAY send all Bcc: posts using bulk delivery, -however this may have privacy implications as there is no guarantee a -receiving system will not log, store, or otherwise reveal the contents of the -Bcc recipient list. - -Z-To: addresses MAY be shown to an end user. - - -Envelope encryption -******************* - - -The entire envelope is encrypted using alg with env_key and env_iv and -base64url encoded for transmission. - -The zot envelope MAY include remote addresses. A zot inbound delivery agent -MUST parse the envelope and determine whether a delivery address to the -current endpoint is valid. This may be the result of: - - 1. An address contains the public message wildcard '*' - - 2. The current endpoint is a personal endpoint and one of the recipients -listed in the Z-To: or Z-Bcc: addresses matches the webfinger address of -the "owner" of the endpoint. - - 3. The current endpoint is a bulk delivery endpoint. The bulk delivery -endpoint is defined elsewhere in this document. The bulk delivery agent -will deliver to all local addresses found in the address lists. - -zot:sig -******* - -The Sender of the message signs the underlying salmon data in the manner -prescribed by salmon. If the Sender and From address are identical, the -signature will be identical to the signature of the underlying salmon packet. -If they are different, this signature is verified with the Sender's public -key to verify the Sender. - -zot:alg -******* - -Currently the only valid choice for alg is "AES-256-CBC". - - -zot:data -******** - -The data field is a salmon magic envelope. This is encrypted with alg using -key and iv. The result is then base64url encoded for transmission. - -For the first release of this specification, the data format of the enclosed -salmon SHOULD be 'application/atom+xml' representing an Atom formatted -ActivityStream. Future revisions MAY allow other alternate data formats. -All acceptable formats MUST be listed in an XRD property (described elsewhere -in this document). - - -Delivery -******** - -The zot message is then POSTed to the zot endpoint URL as -application/text+xml and can be decoded/decrypted by the recipient using -their private key. - -The normal salmon endpoint for a service MAY be used as an alternate -delivery method for non-encrypted (e.g. public) messages. - -Discover of the zot endpoint is based on webfinger XRD: - -<Link rel="http://purl.org/zot/1.0/post" - href="http://example/org/zot-endpoint" /> - - -Bulk Delivery -************* - -A site MAY provide a bulk delivery endpoint, which MAY be used to avoid -multiple encryptions of the same data for a single destination. -This is discoverable by providing a zot endpoint with a corresponding -salmon public key in the site's .well-known/host-meta file. -A delivery to this endpoint will deliver to all local recipients provided -within the zot envelope. - - -Extensibility -************* - -This specification is subject to change. The current version which is in -effect at a given site may be noted by XRD properties. The following -properties MUST be present in the XRD providing the relevant endpoint: - -<Property type="http://purl.org/zot/1.0/version">1</Property> -<Property type="http://purl.org/zot/1.0/accept">application/atom+xml</Property> - - -Version is specified in this document and indicates the current revision. -Version is an increasing non-zero integer value. There are no minor versions. -Implementations MAY provide compatibility to multiple incompatible versions -by using this version indication. The "accept" indicates a range of document -content types which may be enclosed in the underlying salmon magic envelope. -We anticipate this specification will in the future allow for a close variant -of "message/rfc822" and which may include MIME. This may also be used to -embed alternate message formats and protocols such as -"application/x-diaspora+xml". If a delivery agent is unable to provide any -acceptable data format to the remote system, the delivery to that system MUST -be terminated/cancelled. - -Foreign Messages -**************** - -Messages MAY be imported from other networks and systems which have no -knowledge of salmon signatures. The salmon signature in this case MUST be the -exact string 'NOTSIGNED' to indicate that the author (From address) cannot be -validated using salmon verification. This message MUST be relayed by a Sender -who can provide a valid salmon signature of the message via zot:sig. Delivery -systems MAY reject foreign messages. - - - - - -******************************* -* Zid (Zot-ID) authentication * -******************************* - -This section of the document is considered separate from the delivery -specification precding it and represents a different protocol, which is -currently incomplete. This will be split off into another document in the -future, but is presented here as a synergistic component of the Zot network -model. - - -URLs may be present within a zot message which refer to private and/or -protected resources. Zid uses OpenID to gain access to these protected -resources. These could be private photos or profile information - or *any* -web accessible resource. Using zid, these can have access controls which -extends to any resolvable webfinger address. - -Zid authentication relies on the presence of an OpenID provider element in -webfinger, and a URL template which is applied to protected resources within -a zot message. - -The template is designated with the characters "{zid=}" within a URL of a zot -message. When the page is rendered for viewing to an observer, this template -is replaced with the webfinger address of the viewer (if known), or an empty -string if the webfinger address of the viewer cannot be determined. - -For example in a message body: - -http://example.com/photos/bob/picture.jpg?{zid=} - -refers to a private photo which is only visible to alice@example.com. - -If Alice is viewing the page, the link is rendered with - -http://example.com/photos/bob/picture.jpg?zid=alice@example.com - -If the page viewer is unknown, it is rendered as - -http://example.com/photos/bob/picture.jpg?zid= - - -When the link is visited, the web server at example.com notes the presence of -the zid parameter and uses information from webfinger to locate the OpenID -provider for the zid webfinger address. It then redirects to the OpenID -server and requests authentication of the given person. If this is successful, -access to the protected resource is granted. - -A browser cookie may be provided to avoid future authentication redirects -and allow authenticated browsing to other resources on the website. - -Only authentication via OpenID is defined in this version of the specification. - -This can be used to provide access control of any web resource to any -webfinger identity on the internet. - - -********* -* Links * -********* - -Salmon Protocol - http://www.salmon-protocol.org/salmon-protocol-summary - -Salmon Magic Envelope - http://salmon-protocol.googlecode.com/svn/trunk/draft-panzer-magicsig-01.html - -Atom Activity Stream Draft - http://activitystrea.ms/specs/atom/1.0/ - -Activty Stream Base Schema - http://activitystrea.ms/head/activity-schema.html - -WebFinger Protocol - http://code.google.com/p/webfinger/wiki/WebFingerProtocol - - |