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doc/session.txt @ 12180:53e0ae770917
util.xml: Do not allow doctypes, comments or processing instructions
Yes. This is as bad as it sounds. CVE pending.
In Prosody itself, this only affects mod_websocket, which uses util.xml
to parse the <open/> frame, thus allowing unauthenticated remote DoS
using Billion Laughs. However, third-party modules using util.xml may
also be affected by this.
This commit installs handlers which disallow the use of doctype
declarations and processing instructions without any escape hatch. It,
by default, also introduces such a handler for comments, however, there
is a way to enable comments nontheless.
This is because util.xml is used to parse human-facing data, where
comments are generally a desirable feature, and also because comments
are generally harmless.
author | Jonas Schäfer <jonas@wielicki.name> |
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date | Mon, 10 Jan 2022 18:23:54 +0100 |
parent | 8728:41c959c5c84b |
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Structure of a session: session { -- properties -- conn -- the tcp connection notopen -- true if stream has not been initiated, removed after receiving <stream:steam> type -- the connection type. Valid values include: -- "c2s_unauthed" - connection has not been authenticated yet -- "c2s" - from a local client to the server username -- the node part of the client's jid (not defined before auth) host -- the host part of the client's jid (not defined before stream initiation) resource -- the resource part of the client's full jid (not defined before resource binding) full_jid -- convenience for the above 3 as string in username@host/resource form (not defined before resource binding) priority -- the resource priority, default: 0 presence -- the last non-directed presence with no type attribute. initially nil. reset to nil on unavailable presence. interested -- true if the resource requested the roster. Interested resources receive roster updates. Initially nil. roster -- the user's roster. Loaded as soon as the resource is bound (session becomes a connected resource). -- methods -- send(x) -- converts x to a string, and writes it to the connection close(x) -- Disconnect the user and clean up the session, best call sessionmanager.destroy_session() instead of this in most cases } if session.full_jid (also session.roster and session.resource) then this is a "connected resource" if session.presence then this is an "available resource" (all available resources are connected resources) if session.interested then this is an "interested resource" (all interested resources are connected resources)