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mod_host_blacklist/mod_host_blacklist.lua @ 4651:8231774f5bfd
mod_cloud_notify_encrypted: Ensure body substring remains valid UTF-8
The `body:sub()` call risks splitting the string in the middle of a
multi-byte UTF-8 sequence. This should have been caught by util.stanza
validation, but that would have caused some havoc, at the very least causing
the notification to not be sent.
There have been no reports of this happening. Likely because this module
isn't widely deployed among users with languages that use many longer UTF-8
sequences.
The util.encodings.utf8.valid() function is O(n) where only the last
sequence really needs to be checked, but it's in C and expected to be fast.
author | Kim Alvefur <zash@zash.se> |
---|---|
date | Sun, 22 Aug 2021 13:22:59 +0200 |
parent | 1182:547b3c05cc06 |
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local jid_split = require "util.jid".split; local st = require "util.stanza"; local set = require "util.set"; local select = select; local blacklist = module:get_option_inherited_set("host_blacklist", {}); local function stanza_checker(attr) return function (event) local host = select(2, jid_split(event.stanza.attr[attr])); if blacklist:contains(host) then module:send(st.error_reply(event.stanza, "cancel", "not-allowed", "Communication with this domain is restricted")); return true; end end end check_incoming_stanza = stanza_checker("from"); check_outgoing_stanza = stanza_checker("to"); for stanza_type in set.new{"presence","message","iq"}:items() do for jid_type in set.new{"bare", "full", "host"}:items() do module:hook("pre-"..stanza_type.."/"..jid_type, check_outgoing_stanza, 500); module:hook(stanza_type.."/"..jid_type, check_incoming_stanza, 500); end end