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local st = require "util.stanza";
local send = require "core.sessionmanager".send_to_session;
local sm_bind_resource = require "core.sessionmanager".bind_resource;
local jid
local usermanager_validate_credentials = require "core.usermanager".validate_credentials;
local t_concat, t_insert = table.concat, table.insert;
local tostring = tostring;
local jid_split = require "util.jid".split
local log = require "util.logger".init("mod_saslauth");
local xmlns_sasl ='urn:ietf:params:xml:ns:xmpp-sasl';
local xmlns_bind ='urn:ietf:params:xml:ns:xmpp-bind';
local xmlns_stanzas ='urn:ietf:params:xml:ns:xmpp-stanzas';
local new_sasl = require "util.sasl".new;
local function build_reply(status, ret)
local reply = st.stanza(status, {xmlns = xmlns_sasl});
if status == "challenge" then
reply:text(ret or "");
elseif status == "failure" then
reply:tag(ret):up();
elseif status == "success" then
reply:text(ret or "");
else
error("Unknown sasl status: "..status);
end
return reply;
end
local function handle_status(session, status)
if status == "failure" then
session.sasl_handler = nil;
elseif status == "success" then
if not session.sasl_handler.username then error("SASL succeeded but we didn't get a username!"); end -- TODO move this to sessionmanager
sessionmanager.make_authenticated(session, session.sasl_handler.username);
session.sasl_handler = nil;
session:reset_stream();
end
end
local function password_callback(jid, mechanism)
local node, host = jid_split(jid);
local password = (datamanager.load(node, host, "accounts") or {}).password; -- FIXME handle hashed passwords
local func = function(x) return x; end;
if password then
if mechanism == "PLAIN" then
return func, password;
elseif mechanism == "DIGEST-MD5" then
return func, require "hashes".md5(node.."::"..password);
end
end
return func, nil;
end
function do_sasl(session, stanza)
local text = stanza[1];
if text then
text = base64.decode(text);
if not text then
session.sasl_handler = nil;
session.send(build_reply("failure", "incorrect-encoding"));
return;
end
end
local status, ret = session.sasl_handler:feed(text);
handle_status(session, status);
local s = build_reply(status, ret);
log("debug", "sasl reply: "..tostring(s));
session.send(s);
end
add_handler("c2s_unauthed", "auth", xmlns_sasl,
function (session, stanza)
if not session.sasl_handler then
session.sasl_handler = new_sasl(stanza.attr.mechanism, session.host, password_callback);
do_sasl(session, stanza);
else
error("Client tried to negotiate SASL again", 0);
end
end);
add_handler("c2s_unauthed", "abort", xmlns_sasl,
function(session, stanza)
if not session.sasl_handler then error("Attempt to abort when sasl has not started"); end
do_sasl(session, stanza);
end);
add_handler("c2s_unauthed", "response", xmlns_sasl,
function(session, stanza)
if not session.sasl_handler then error("Attempt to respond when sasl has not started"); end
do_sasl(session, stanza);
end);
add_event_hook("stream-features",
function (session, features)
if not session.username then
t_insert(features, "<mechanisms xmlns='urn:ietf:params:xml:ns:xmpp-sasl'>");
-- TODO: Provide PLAIN only if TLS is active, this is a SHOULD from the introduction of RFC 4616. This behavior could be overridden via configuration but will issuing a warning or so.
t_insert(features, "<mechanism>PLAIN</mechanism>");
-- t_insert(features, "<mechanism>DIGEST-MD5</mechanism>");
t_insert(features, "</mechanisms>");
else
t_insert(features, "<bind xmlns='urn:ietf:params:xml:ns:xmpp-bind'><required/></bind>");
t_insert(features, "<session xmlns='urn:ietf:params:xml:ns:xmpp-session'/>");
end
--send [[<register xmlns="http://jabber.org/features/iq-register"/> ]]
end);
add_iq_handler("c2s", "urn:ietf:params:xml:ns:xmpp-bind",
function (session, stanza)
log("debug", "Client tried to bind to a resource");
local resource;
if stanza.attr.type == "set" then
local bind = stanza.tags[1];
if bind and bind.attr.xmlns == xmlns_bind then
resource = bind:child_with_name("resource");
if resource then
resource = resource[1];
end
end
end
local success, err = sm_bind_resource(session, resource);
if not success then
local reply = st.reply(stanza);
reply.attr.type = "error";
if err == "conflict" then
reply:tag("error", { type = "modify" })
:tag("conflict", { xmlns = xmlns_stanzas });
elseif err == "constraint" then
reply:tag("error", { type = "cancel" })
:tag("resource-constraint", { xmlns = xmlns_stanzas });
elseif err == "auth" then
reply:tag("error", { type = "cancel" })
:tag("not-allowed", { xmlns = xmlns_stanzas });
end
send(session, reply);
else
local reply = st.reply(stanza);
reply:tag("bind", { xmlns = xmlns_bind})
:tag("jid"):text(session.full_jid);
send(session, reply);
end
end);
add_iq_handler("c2s", "urn:ietf:params:xml:ns:xmpp-session",
function (session, stanza)
log("debug", "Client tried to bind to a resource");
send(session, st.reply(stanza));
end);
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