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Diffstat (limited to 'plugins/mod_blocklist.lua')
| -rw-r--r-- | plugins/mod_blocklist.lua | 325 |
1 files changed, 325 insertions, 0 deletions
diff --git a/plugins/mod_blocklist.lua b/plugins/mod_blocklist.lua new file mode 100644 index 00000000..8efbfd96 --- /dev/null +++ b/plugins/mod_blocklist.lua @@ -0,0 +1,325 @@ +-- Prosody IM +-- Copyright (C) 2009-2010 Matthew Wild +-- Copyright (C) 2009-2010 Waqas Hussain +-- Copyright (C) 2014-2015 Kim Alvefur +-- +-- This project is MIT/X11 licensed. Please see the +-- COPYING file in the source package for more information. +-- +-- This module implements XEP-0191: Blocking Command +-- + +local user_exists = require"core.usermanager".user_exists; +local rostermanager = require"core.rostermanager"; +local is_contact_subscribed = rostermanager.is_contact_subscribed; +local is_contact_pending_in = rostermanager.is_contact_pending_in; +local load_roster = rostermanager.load_roster; +local save_roster = rostermanager.save_roster; +local st = require"util.stanza"; +local st_error_reply = st.error_reply; +local jid_prep = require"util.jid".prep; +local jid_split = require"util.jid".split; + +local storage = module:open_store(); +local sessions = prosody.hosts[module.host].sessions; + +-- First level cache of blocklists by username. +-- Weak table so may randomly expire at any time. +local cache = setmetatable({}, { __mode = "v" }); + +-- Second level of caching, keeps a fixed number of items, also anchors +-- items in the above cache. +-- +-- The size of this affects how often we will need to load a blocklist from +-- disk, which we want to avoid during routing. On the other hand, we don't +-- want to use too much memory either, so this can be tuned by advanced +-- users. TODO use science to figure out a better default, 64 is just a guess. +local cache_size = module:get_option_number("blocklist_cache_size", 64); +local cache2 = require"util.cache".new(cache_size); + +local null_blocklist = {}; + +module:add_feature("urn:xmpp:blocking"); + +local function set_blocklist(username, blocklist) + local ok, err = storage:set(username, blocklist); + if not ok then + return ok, err; + end + -- Successful save, update the cache + cache2:set(username, blocklist); + cache[username] = blocklist; + return true; +end + +-- Migrates from the old mod_privacy storage +local function migrate_privacy_list(username) + local migrated_data = { [false] = "not empty" }; + local legacy_data = module:open_store("privacy"):get(username); + if legacy_data and legacy_data.lists and legacy_data.default then + legacy_data = legacy_data.lists[legacy_data.default]; + legacy_data = legacy_data and legacy_data.items; + else + return migrated_data; + end + if legacy_data then + module:log("info", "Migrating blocklist from mod_privacy storage for user '%s'", username); + local item, jid; + for i = 1, #legacy_data do + item = legacy_data[i]; + if item.type == "jid" and item.action == "deny" then + jid = jid_prep(item.value); + if not jid then + module:log("warn", "Invalid JID in privacy store for user '%s' not migrated: %s", username, tostring(item.value)); + else + migrated_data[jid] = true; + end + end + end + end + set_blocklist(username, migrated_data); + return migrated_data; +end + +local function get_blocklist(username) + local blocklist = cache[username]; + if not blocklist then + blocklist = cache2:get(username); + end + if not blocklist then + if not user_exists(username, module.host) then + return null_blocklist; + end + blocklist = storage:get(username); + if not blocklist then + blocklist = migrate_privacy_list(username); + end + cache2:set(username, blocklist); + end + cache[username] = blocklist; + return blocklist; +end + +module:hook("iq-get/self/urn:xmpp:blocking:blocklist", function (event) + local origin, stanza = event.origin, event.stanza; + local username = origin.username; + local reply = st.reply(stanza):tag("blocklist", { xmlns = "urn:xmpp:blocking" }); + local blocklist = get_blocklist(username); + for jid in pairs(blocklist) do + if jid then + reply:tag("item", { jid = jid }):up(); + end + end + origin.interested_blocklist = true; -- Gets notified about changes + origin.send(reply); + return true; +end); + +-- Add or remove some jid(s) from the blocklist +-- We want this to be atomic and not do a partial update +local function edit_blocklist(event) + local origin, stanza = event.origin, event.stanza; + local username = origin.username; + local action = stanza.tags[1]; -- "block" or "unblock" + local is_blocking = action.name == "block" or nil; -- nil if unblocking + local new = {}; -- JIDs to block depending or unblock on action + + -- XEP-0191 sayeth: + -- > When the user blocks communications with the contact, the user's + -- > server MUST send unavailable presence information to the contact (but + -- > only if the contact is allowed to receive presence notifications [...] + -- So contacts we need to do that for are added to the set below. + local send_unavailable = is_blocking and {}; + + -- Because blocking someone currently also blocks the ability to reject + -- subscription requests, we'll preemptively reject such + local remove_pending = is_blocking and {}; + + for item in action:childtags("item") do + local jid = jid_prep(item.attr.jid); + if not jid then + origin.send(st_error_reply(stanza, "modify", "jid-malformed")); + return true; + end + item.attr.jid = jid; -- echo back prepped + new[jid] = true; + if is_blocking then + if is_contact_subscribed(username, module.host, jid) then + send_unavailable[jid] = true; + elseif is_contact_pending_in(username, module.host, jid) then + remove_pending[jid] = true; + end + end + end + + if is_blocking and not next(new) then + -- <block/> element does not contain at least one <item/> child element + origin.send(st_error_reply(stanza, "modify", "bad-request")); + return true; + end + + local blocklist = get_blocklist(username); + + local new_blocklist = {}; + + if is_blocking or next(new) then + for jid in pairs(blocklist) do + new_blocklist[jid] = true; + end + for jid in pairs(new) do + new_blocklist[jid] = is_blocking; + end + -- else empty the blocklist + end + new_blocklist[false] = "not empty"; -- In order to avoid doing the migration thing twice + + local ok, err = set_blocklist(username, new_blocklist); + if ok then + origin.send(st.reply(stanza)); + else + origin.send(st_error_reply(stanza, "wait", "internal-server-error", err)); + return true; + end + + if is_blocking then + for jid in pairs(send_unavailable) do + if not blocklist[jid] then + for _, session in pairs(sessions[username].sessions) do + if session.presence then + module:send(st.presence({ type = "unavailable", to = jid, from = session.full_jid })); + end + end + end + end + + if next(remove_pending) then + local roster = load_roster(username, module.host); + for jid in pairs(remove_pending) do + roster[false].pending[jid] = nil; + end + save_roster(username, module.host, roster); + -- Not much we can do about save failing here + end + end + + local blocklist_push = st.iq({ type = "set", id = "blocklist-push" }) + :add_child(action); -- I am lazy + + for _, session in pairs(sessions[username].sessions) do + if session.interested_blocklist then + blocklist_push.attr.to = session.full_jid; + session.send(blocklist_push); + end + end + + return true; +end + +module:hook("iq-set/self/urn:xmpp:blocking:block", edit_blocklist); +module:hook("iq-set/self/urn:xmpp:blocking:unblock", edit_blocklist); + +-- Cache invalidation, solved! +module:hook_global("user-deleted", function (event) + if event.host == module.host then + cache2:set(event.username, nil); + cache[event.username] = nil; + end +end); + +-- Buggy clients +module:hook("iq-error/self/blocklist-push", function (event) + local _, condition, text = event.stanza:get_error(); + (event.origin.log or module._log)("warn", "Client returned an error in response to notification from mod_%s: %s%s%s", module.name, condition, text and ": " or "", text or ""); + return true; +end); + +local function is_blocked(user, jid) + local blocklist = cache[user] or get_blocklist(user); + if blocklist[jid] then return true; end + local node, host = jid_split(jid); + return blocklist[host] or node and blocklist[node..'@'..host]; +end + +-- Event handlers for bouncing or dropping stanzas +local function drop_stanza(event) + local stanza = event.stanza; + local attr = stanza.attr; + local to, from = attr.to, attr.from; + to = to and jid_split(to); + if to and from then + return is_blocked(to, from); + end +end + +local function bounce_stanza(event) + local origin, stanza = event.origin, event.stanza; + if drop_stanza(event) then + origin.send(st_error_reply(stanza, "cancel", "service-unavailable")); + return true; + end +end + +local function bounce_iq(event) + local type = event.stanza.attr.type; + if type == "set" or type == "get" then + return bounce_stanza(event); + end + return drop_stanza(event); -- result or error +end + +local function bounce_message(event) + local type = event.stanza.attr.type; + if type == "chat" or not type or type == "normal" then + return bounce_stanza(event); + end + return drop_stanza(event); -- drop headlines, groupchats etc +end + +local function drop_outgoing(event) + local origin, stanza = event.origin, event.stanza; + local username = origin.username or jid_split(stanza.attr.from); + if not username then return end + local to = stanza.attr.to; + if to then return is_blocked(username, to); end + -- nil 'to' means a self event, don't bock those +end + +local function bounce_outgoing(event) + local origin, stanza = event.origin, event.stanza; + local type = stanza.attr.type; + if type == "error" or stanza.name == "iq" and type == "result" then + return drop_outgoing(event); + end + if drop_outgoing(event) then + origin.send(st_error_reply(stanza, "cancel", "not-acceptable", "You have blocked this JID") + :tag("blocked", { xmlns = "urn:xmpp:blocking:errors" })); + return true; + end +end + +-- Hook all the events! +local prio_in, prio_out = 100, 100; +module:hook("presence/bare", drop_stanza, prio_in); +module:hook("presence/full", drop_stanza, prio_in); + +module:hook("message/bare", bounce_message, prio_in); +module:hook("message/full", bounce_message, prio_in); + +module:hook("iq/bare", bounce_iq, prio_in); +module:hook("iq/full", bounce_iq, prio_in); + +module:hook("pre-message/bare", bounce_outgoing, prio_out); +module:hook("pre-message/full", bounce_outgoing, prio_out); +module:hook("pre-message/host", bounce_outgoing, prio_out); + +-- Note: MUST bounce these, but we don't because this would produce +-- lots of error replies due to server-generated presence. +-- FIXME some day, likely needing changes to mod_presence +module:hook("pre-presence/bare", drop_outgoing, prio_out); +module:hook("pre-presence/full", drop_outgoing, prio_out); +module:hook("pre-presence/host", drop_outgoing, prio_out); + +module:hook("pre-iq/bare", bounce_outgoing, prio_out); +module:hook("pre-iq/full", bounce_outgoing, prio_out); +module:hook("pre-iq/host", bounce_outgoing, prio_out); + |