Mercurial > prosody-modules
view mod_muc_ban_ip/mod_muc_ban_ip.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 |
parents | a7a06c8cea37 |
children | 47d9f704d14b |
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module:set_global(); local jid_bare = require "util.jid".bare; local st = require "util.stanza"; local xmlns_muc_user = "http://jabber.org/protocol/muc#user"; local ip_bans = module:shared("bans"); local full_sessions = prosody.full_sessions; local function ban_ip(session, from) local ip = session.ip; if not ip then module:log("warn", "Failed to ban IP (IP unknown) for %s", session.full_jid); return; end local banned_from = ip_bans[ip]; if not banned_from then banned_from = {}; ip_bans[ip] = banned_from; end banned_from[from] = true; module:log("debug", "Added ban for IP address %s from %s", ip, from); end local function check_for_incoming_ban(event) local stanza = event.stanza; local to_session = full_sessions[stanza.attr.to]; if to_session then local directed = to_session.directed; local from = stanza.attr.from; if directed and directed[from] and stanza.attr.type == "unavailable" then -- This is a stanza from somewhere we sent directed presence to (may be a MUC) local x = stanza:get_child("x", xmlns_muc_user); if x then for status in x:childtags("status") do if status.attr.code == '301' then ban_ip(to_session, jid_bare(from)); end end end end end end local function check_for_ban(event) local origin, stanza = event.origin, event.stanza; local ip = origin.ip; local to = jid_bare(stanza.attr.to); if ip_bans[ip] and ip_bans[ip][to] then (origin.log or module._log)("debug", "IP banned: %s is banned from %s", ip, to) if stanza.attr.type ~= "error" then origin.send(st.error_reply(stanza, "auth", "forbidden") :tag("x", { xmlns = xmlns_muc_user }) :tag("status", { code = '301' })); end return true; end (origin.log or module._log)("debug", "IP not banned: %s from %s", ip, to) end function module.add_host(module) module:hook("presence/full", check_for_incoming_ban, 100); module:hook("pre-presence/full", check_for_ban, 100); end