-- XEP-0357: Push (aka: My mobile OS vendor won't let me have persistent TCP connections)
-- Copyright (C) 2015-2016 Kim Alvefur
-- Copyright (C) 2017 Thilo Molitor
--
-- This file is MIT/X11 licensed.
local t_insert = table.insert;
local s_match = string.match;
local s_sub = string.sub;
local st = require"util.stanza";
local jid = require"util.jid";
local dataform = require"util.dataforms".new;
local filters = require"util.filters";
local hashes = require"util.hashes";
local xmlns_push = "urn:xmpp:push:0";
-- configuration
local include_body = module:get_option_boolean("push_notification_with_body", false);
local include_sender = module:get_option_boolean("push_notification_with_sender", false);
local max_push_errors = module:get_option_number("push_max_errors", 50);
local dummy_body = module:get_option_string("push_notification_important_body", "");
local host_sessions = prosody.hosts[module.host].sessions;
local push_errors = {};
local id2node = {};
-- For keeping state across reloads while caching reads
local push_store = (function()
local store = module:open_store();
local push_services = {};
local api = {};
function api:get(user)
if not push_services[user] then
local err;
push_services[user], err = store:get(user);
if not push_services[user] and err then
module:log("warn", "Error reading push notification storage for user '%s': %s", user, tostring(err));
push_services[user] = {};
return push_services[user], false;
end
end
if not push_services[user] then push_services[user] = {} end
return push_services[user], true;
end
function api:set(user, data)
push_services[user] = data;
local ok, err = store:set(user, push_services[user]);
if not ok then
module:log("error", "Error writing push notification storage for user '%s': %s", user, tostring(err));
return false;
end
return true;
end
function api:set_identifier(user, push_identifier, data)
local services = self:get(user);
services[push_identifier] = data;
return self:set(user, services);
end
return api;
end)();
-- Forward declarations, as both functions need to reference each other
local handle_push_success, handle_push_error;
function handle_push_error(event)
local stanza = event.stanza;
local error_type, condition = stanza:get_error();
local node = id2node[stanza.attr.id];
if node == nil then return false; end -- unknown stanza? Ignore for now!
local from = stanza.attr.from;
local user_push_services = push_store:get(node);
for push_identifier, _ in pairs(user_push_services) do
local stanza_id = hashes.sha256(push_identifier, true);
if stanza_id == stanza.attr.id then
if user_push_services[push_identifier] and user_push_services[push_identifier].jid == from and error_type ~= "wait" then
push_errors[push_identifier] = push_errors[push_identifier] + 1;
module:log("info", "Got error of type '%s' (%s) for identifier '%s': "
.."error count for this identifier is now at %s", error_type, condition, push_identifier,
tostring(push_errors[push_identifier]));
if push_errors[push_identifier] >= max_push_errors then
module:log("warn", "Disabling push notifications for identifier '%s'", push_identifier);
-- remove push settings from sessions
if host_sessions[node] then
for _, session in pairs(host_sessions[node].sessions) do
if session.push_identifier == push_identifier then
session.push_identifier = nil;
session.push_settings = nil;
end
end
end
-- save changed global config
push_store:set_identifier(node, push_identifier, nil);
push_errors[push_identifier] = nil;
-- unhook iq handlers for this identifier (if possible)
if module.unhook then
module:unhook("iq-error/host/"..stanza_id, handle_push_error);
module:unhook("iq-result/host/"..stanza_id, handle_push_success);
id2node[stanza_id] = nil;
end
end
elseif user_push_services[push_identifier] and user_push_services[push_identifier].jid == from and error_type == "wait" then
module:log("debug", "Got error of type '%s' (%s) for identifier '%s': "
.."NOT increasing error count for this identifier", error_type, condition, push_identifier);
end
end
end
return true;
end
function handle_push_success(event)
local stanza = event.stanza;
local node = id2node[stanza.attr.id];
if node == nil then return false; end -- unknown stanza? Ignore for now!
local from = stanza.attr.from;
local user_push_services = push_store:get(node);
for push_identifier, _ in pairs(user_push_services) do
if hashes.sha256(push_identifier, true) == stanza.attr.id then
if user_push_services[push_identifier] and user_push_services[push_identifier].jid == from and push_errors[push_identifier] > 0 then
push_errors[push_identifier] = 0;
module:log("debug", "Push succeeded, error count for identifier '%s' is now at %s again", push_identifier, tostring(push_errors[push_identifier]));
end
end
end
return true;
end
-- http://xmpp.org/extensions/xep-0357.html#disco
local function account_dico_info(event)
(event.reply or event.stanza):tag("feature", {var=xmlns_push}):up();
end
module:hook("account-disco-info", account_dico_info);
-- http://xmpp.org/extensions/xep-0357.html#enabling
local function push_enable(event)
local origin, stanza = event.origin, event.stanza;
local enable = stanza.tags[1];
origin.log("debug", "Attempting to enable push notifications");
-- MUST contain a 'jid' attribute of the XMPP Push Service being enabled
local push_jid = enable.attr.jid;
-- SHOULD contain a 'node' attribute
local push_node = enable.attr.node;
-- CAN contain a 'include_payload' attribute
local include_payload = enable.attr.include_payload;
if not push_jid then
origin.log("debug", "Push notification enable request missing the 'jid' field");
origin.send(st.error_reply(stanza, "modify", "bad-request", "Missing jid"));
return true;
end
local publish_options = enable:get_child("x", "jabber:x:data");
if not publish_options then
-- Could be intentional
origin.log("debug", "No publish options in request");
end
local push_identifier = push_jid .. "<" .. (push_node or "");
local push_service = {
jid = push_jid;
node = push_node;
include_payload = include_payload;
options = publish_options and st.preserialize(publish_options);
};
local ok = push_store:set_identifier(origin.username, push_identifier, push_service);
if not ok then
origin.send(st.error_reply(stanza, "wait", "internal-server-error"));
else
origin.push_identifier = push_identifier;
origin.push_settings = push_service;
origin.log("info", "Push notifications enabled for %s (%s)", tostring(stanza.attr.from), tostring(origin.push_identifier));
origin.send(st.reply(stanza));
end
return true;
end
module:hook("iq-set/self/"..xmlns_push..":enable", push_enable);
-- http://xmpp.org/extensions/xep-0357.html#disabling
local function push_disable(event)
local origin, stanza = event.origin, event.stanza;
local push_jid = stanza.tags[1].attr.jid; -- MUST include a 'jid' attribute
local push_node = stanza.tags[1].attr.node; -- A 'node' attribute MAY be included
if not push_jid then
origin.send(st.error_reply(stanza, "modify", "bad-request", "Missing jid"));
return true;
end
local user_push_services = push_store:get(origin.username);
for key, push_info in pairs(user_push_services) do
if push_info.jid == push_jid and (not push_node or push_info.node == push_node) then
origin.log("info", "Push notifications disabled (%s)", tostring(key));
if origin.push_identifier == key then
origin.push_identifier = nil;
origin.push_settings = nil;
end
user_push_services[key] = nil;
push_errors[key] = nil;
if module.unhook then
module:unhook("iq-error/host/"..key, handle_push_error);
module:unhook("iq-result/host/"..key, handle_push_success);
id2node[key] = nil;
end
end
end
local ok = push_store:set(origin.username, user_push_services);
if not ok then
origin.send(st.error_reply(stanza, "wait", "internal-server-error"));
else
origin.send(st.reply(stanza));
end
return true;
end
module:hook("iq-set/self/"..xmlns_push..":disable", push_disable);
-- Patched version of util.stanza:find() that supports giving stanza names
-- without their namespace, allowing for every namespace.
local function find(self, path)
local pos = 1;
local len = #path + 1;
repeat
local xmlns, name, text;
local char = s_sub(path, pos, pos);
if char == "@" then
return self.attr[s_sub(path, pos + 1)];
elseif char == "{" then
xmlns, pos = s_match(path, "^([^}]+)}()", pos + 1);
end
name, text, pos = s_match(path, "^([^@/#]*)([/#]?)()", pos);
name = name ~= "" and name or nil;
if pos == len then
if text == "#" then
local child = xmlns ~= nil and self:get_child(name, xmlns) or self:child_with_name(name);
return child and child:get_text() or nil;
end
return xmlns ~= nil and self:get_child(name, xmlns) or self:child_with_name(name);
end
self = xmlns ~= nil and self:get_child(name, xmlns) or self:child_with_name(name);
until not self
return nil;
end
-- is this push a high priority one (this is needed for ios apps not using voip pushes)
local function is_important(stanza)
local st_name = stanza and stanza.name or nil;
if not st_name then return false; end -- nonzas are never important here
if st_name == "presence" then
return false; -- same for presences
elseif st_name == "message" then
-- unpack carbon copies
local stanza_direction = "in";
local carbon;
local st_type;
-- support carbon copied message stanzas having an arbitrary message-namespace or no message-namespace at all
if not carbon then carbon = find(stanza, "{urn:xmpp:carbons:2}/forwarded/message"); end
if not carbon then carbon = find(stanza, "{urn:xmpp:carbons:1}/forwarded/message"); end
stanza_direction = carbon and stanza:child_with_name("sent") and "out" or "in";
if carbon then stanza = carbon; end
st_type = stanza.attr.type;
-- headline message are always not important
if st_type == "headline" then return false; end
-- carbon copied outgoing messages are not important
if carbon and stanza_direction == "out" then return false; end
-- We can't check for body contents in encrypted messages, so let's treat them as important
-- Some clients don't even set a body or an empty body for encrypted messages
-- check omemo https://xmpp.org/extensions/inbox/omemo.html
if stanza:get_child("encrypted", "eu.siacs.conversations.axolotl") or stanza:get_child("encrypted", "urn:xmpp:omemo:0") then return true; end
-- check xep27 pgp https://xmpp.org/extensions/xep-0027.html
if stanza:get_child("x", "jabber:x:encrypted") then return true; end
-- check xep373 pgp (OX) https://xmpp.org/extensions/xep-0373.html
if stanza:get_child("openpgp", "urn:xmpp:openpgp:0") then return true; end
local body = stanza:get_child_text("body");
if st_type == "groupchat" and stanza:get_child_text("subject") then return false; end -- groupchat subjects are not important here
return body ~= nil and body ~= ""; -- empty bodies are not important
end
return false; -- this stanza wasn't one of the above cases --> it is not important, too
end
local push_form = dataform {
{ name = "FORM_TYPE"; type = "hidden"; value = "urn:xmpp:push:summary"; };
{ name = "message-count"; type = "text-single"; };
{ name = "pending-subscription-count"; type = "text-single"; };
{ name = "last-message-sender"; type = "jid-single"; };
{ name = "last-message-body"; type = "text-single"; };
};
-- http://xmpp.org/extensions/xep-0357.html#publishing
local function handle_notify_request(stanza, node, user_push_services)
local pushes = 0;
if not user_push_services or not #user_push_services then return pushes end
for push_identifier, push_info in pairs(user_push_services) do
local send_push = true; -- only send push to this node when not already done for this stanza or if no stanza is given at all
if stanza then
if not stanza._push_notify then stanza._push_notify = {}; end
if stanza._push_notify[push_identifier] then
module:log("debug", "Already sent push notification for %s@%s to %s (%s)", node, module.host, push_info.jid, tostring(push_info.node));
send_push = false;
end
stanza._push_notify[push_identifier] = true;
end
if send_push then
-- construct push stanza
local stanza_id = hashes.sha256(push_identifier, true);
local push_publish = st.iq({ to = push_info.jid, from = module.host, type = "set", id = stanza_id })
:tag("pubsub", { xmlns = "http://jabber.org/protocol/pubsub" })
:tag("publish", { node = push_info.node })
:tag("item")
:tag("notification", { xmlns = xmlns_push });
local form_data = {
-- hardcode to 1 because other numbers are just meaningless (the XEP does not specify *what exactly* to count)
["message-count"] = "1";
};
if stanza and include_sender then
form_data["last-message-sender"] = stanza.attr.from;
end
if stanza and include_body then
form_data["last-message-body"] = stanza:get_child_text("body");
elseif stanza and dummy_body ~= "" and is_important(stanza) then
form_data["last-message-body"] = dummy_body;
end
push_publish:add_child(push_form:form(form_data));
push_publish:up(); -- / notification
push_publish:up(); -- / publish
push_publish:up(); -- / pubsub
if push_info.options then
push_publish:tag("publish-options"):add_child(st.deserialize(push_info.options));
end
-- send out push
module:log("debug", "Sending push notification for %s@%s to %s (%s)", node, module.host, push_info.jid, tostring(push_info.node));
-- module:log("debug", "PUSH STANZA: %s", tostring(push_publish));
-- handle push errors for this node
if push_errors[push_identifier] == nil then
push_errors[push_identifier] = 0;
module:hook("iq-error/host/"..stanza_id, handle_push_error);
module:hook("iq-result/host/"..stanza_id, handle_push_success);
id2node[stanza_id] = node;
end
module:send(push_publish);
pushes = pushes + 1;
end
end
return pushes;
end
-- small helper function to extract relevant push settings
local function get_push_settings(stanza, session)
local to = stanza.attr.to;
local node = to and jid.split(to) or session.username;
local user_push_services = push_store:get(node);
return node, user_push_services;
end
-- publish on offline message
module:hook("message/offline/handle", function(event)
local node, user_push_services = get_push_settings(event.stanza, event.origin);
module:log("debug", "Invoking cloud handle_notify_request() for offline stanza");
handle_notify_request(event.stanza, node, user_push_services);
end, 1);
-- publish on unacked smacks message
local function process_smacks_stanza(stanza, session)
if session.push_identifier then
session.log("debug", "Invoking cloud handle_notify_request() for smacks queued stanza");
local user_push_services = {[session.push_identifier] = session.push_settings};
local node = get_push_settings(stanza, session);
handle_notify_request(stanza, node, user_push_services);
end
return stanza;
end
local function process_smacks_queue(queue, session)
if not session.push_identifier then return; end
local user_push_services = {[session.push_identifier] = session.push_settings};
for i=1, #queue do
local stanza = queue[i];
local node = get_push_settings(stanza, session);
session.log("debug", "Invoking cloud handle_notify_request() for smacks queued stanza: %d", i);
if handle_notify_request(stanza, node, user_push_services) ~= 0 then
session.log("debug", "Cloud handle_notify_request() > 0, not notifying for other queued stanzas");
return; -- only notify for one stanza in the queue, not for all in a row
end
end
end
-- smacks hibernation is started
local function hibernate_session(event)
local session = event.origin;
local queue = event.queue;
-- process unacked stanzas
process_smacks_queue(queue, session);
-- process future unacked (hibernated) stanzas
filters.add_filter(session, "stanzas/out", process_smacks_stanza, -990);
end
-- smacks hibernation is ended
local function restore_session(event)
local session = event.resumed;
if session then -- older smacks module versions send only the "intermediate" session in event.session and no session.resumed one
filters.remove_filter(session, "stanzas/out", process_smacks_stanza);
end
end
-- smacks ack is delayed
local function ack_delayed(event)
local session = event.origin;
local queue = event.queue;
-- process unacked stanzas (handle_notify_request() will only send push requests for new stanzas)
process_smacks_queue(queue, session);
end
-- archive message added
local function archive_message_added(event)
-- event is: { origin = origin, stanza = stanza, for_user = store_user, id = id }
-- only notify for new mam messages when at least one device is only
if not event.for_user or not host_sessions[event.for_user] then return; end
local stanza = event.stanza;
local user_session = host_sessions[event.for_user].sessions;
local to = stanza.attr.to;
to = to and jid.split(to) or event.origin.username;
-- only notify if the stanza destination is the mam user we store it for
if event.for_user == to then
local user_push_services = push_store:get(to);
if not #user_push_services then return end
-- only notify nodes with no active sessions (smacks is counted as active and handled separate)
local notify_push_sevices = {};
for identifier, push_info in pairs(user_push_services) do
local identifier_found = nil;
for _, session in pairs(user_session) do
-- module:log("debug", "searching for '%s': identifier '%s' for session %s", tostring(identifier), tostring(session.push_identifier), tostring(session.full_jid));
if session.push_identifier == identifier then
identifier_found = session;
break;
end
end
if identifier_found then
identifier_found.log("debug", "Not cloud notifying '%s' of new MAM stanza (session still alive)", identifier);
else
notify_push_sevices[identifier] = push_info;
end
end
handle_notify_request(event.stanza, to, notify_push_sevices);
end
end
module:hook("smacks-hibernation-start", hibernate_session);
module:hook("smacks-hibernation-end", restore_session);
module:hook("smacks-ack-delayed", ack_delayed);
module:hook("archive-message-added", archive_message_added);
local function send_ping(event)
local user = event.user;
local user_push_services = push_store:get(user);
local push_services = event.push_services or user_push_services;
handle_notify_request(nil, user, push_services);
end
-- can be used by other modules to ping one or more (or all) push endpoints
module:hook("cloud-notify-ping", send_ping);
module:log("info", "Module loaded");
function module.unload()
if module.unhook then
module:unhook("account-disco-info", account_dico_info);
module:unhook("iq-set/self/"..xmlns_push..":enable", push_enable);
module:unhook("iq-set/self/"..xmlns_push..":disable", push_disable);
module:unhook("smacks-hibernation-start", hibernate_session);
module:unhook("smacks-hibernation-end", restore_session);
module:unhook("smacks-ack-delayed", ack_delayed);
module:unhook("archive-message-added", archive_message_added);
module:unhook("cloud-notify-ping", send_ping);
for push_identifier, _ in pairs(push_errors) do
local stanza_id = hashes.sha256(push_identifier, true);
module:unhook("iq-error/host/"..stanza_id, handle_push_error);
module:unhook("iq-result/host/"..stanza_id, handle_push_success);
id2node[stanza_id] = nil;
end
end
module:log("info", "Module unloaded");
end