net.http.server: Properly handle persistent connections
[prosody.git] / plugins / mod_saslauth.lua
index c6ead31a49f2aba14af9a01414ba1ee2ad0d93d5..f6abd3b88838f34371ba7524cab26b378e07a63b 100644 (file)
 local st = require "util.stanza";
 local sm_bind_resource = require "core.sessionmanager".bind_resource;
 local sm_make_authenticated = require "core.sessionmanager".make_authenticated;
+local s2s_make_authenticated = require "core.s2smanager".make_authenticated;
 local base64 = require "util.encodings".base64;
 
-local nodeprep = require "util.encodings".stringprep.nodeprep;
+local cert_verify_identity = require "util.x509".verify_identity;
+
 local usermanager_get_sasl_handler = require "core.usermanager".get_sasl_handler;
-local t_concat, t_insert = table.concat, table.insert;
 local tostring = tostring;
 
 local secure_auth_only = module:get_option("c2s_require_encryption") or module:get_option("require_encryption");
-local anonymous_login = module:get_option("anonymous_login");
 local allow_unencrypted_plain_auth = module:get_option("allow_unencrypted_plain_auth")
 
 local log = module._log;
 
 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 anonymous_authentication_profile = {
-       anonymous = function(username, realm)
-               return true; -- for normal usage you should always return true here
-       end
-};
 
 local function build_reply(status, ret, err_msg)
        local reply = st.stanza(status, {xmlns = xmlns_sasl});
@@ -55,16 +46,17 @@ end
 
 local function handle_status(session, status, ret, err_msg)
        if status == "failure" then
+               module:fire_event("authentication-failure", { session = session, condition = ret, text = err_msg });
                session.sasl_handler = session.sasl_handler:clean_clone();
        elseif status == "success" then
-               local username = nodeprep(session.sasl_handler.username);
-
                local ok, err = sm_make_authenticated(session, session.sasl_handler.username);
                if ok then
+                       module:fire_event("authentication-success", { session = session });
                        session.sasl_handler = nil;
                        session:reset_stream();
                else
                        module:log("warn", "SASL succeeded but username was invalid");
+                       module:fire_event("authentication-failure", { session = session, condition = "not-authorized", text = err });
                        session.sasl_handler = session.sasl_handler:clean_clone();
                        return "failure", "not-authorized", "User authenticated successfully, but username was invalid";
                end
@@ -91,30 +83,134 @@ local function sasl_process_cdata(session, stanza)
        return true;
 end
 
+module:hook_stanza(xmlns_sasl, "success", function (session, stanza)
+       if session.type ~= "s2sout_unauthed" or session.external_auth ~= "attempting" then return; end
+       module:log("debug", "SASL EXTERNAL with %s succeeded", session.to_host);
+       session.external_auth = "succeeded"
+       session:reset_stream();
+
+       local default_stream_attr = {xmlns = "jabber:server", ["xmlns:stream"] = "http://etherx.jabber.org/streams",
+                                   ["xmlns:db"] = 'jabber:server:dialback', version = "1.0", to = session.to_host, from = session.from_host};
+       session.sends2s("<?xml version='1.0'?>");
+       session.sends2s(st.stanza("stream:stream", default_stream_attr):top_tag());
+
+       s2s_make_authenticated(session, session.to_host);
+       return true;
+end)
+
+module:hook_stanza(xmlns_sasl, "failure", function (session, stanza)
+       if session.type ~= "s2sout_unauthed" or session.external_auth ~= "attempting" then return; end
+
+       module:log("info", "SASL EXTERNAL with %s failed", session.to_host)
+       -- TODO: Log the failure reason
+       session.external_auth = "failed"
+end, 500)
+
+module:hook_stanza(xmlns_sasl, "failure", function (session, stanza)
+       -- TODO: Dialback wasn't loaded.  Do something useful.
+end, 90)
+
+module:hook_stanza("http://etherx.jabber.org/streams", "features", function (session, stanza)
+       if session.type ~= "s2sout_unauthed" or not session.secure then return; end
+
+       local mechanisms = stanza:get_child("mechanisms", xmlns_sasl)
+       if mechanisms then
+               for mech in mechanisms:childtags() do
+                       if mech[1] == "EXTERNAL" then
+                               module:log("debug", "Initiating SASL EXTERNAL with %s", session.to_host);
+                               local reply = st.stanza("auth", {xmlns = xmlns_sasl, mechanism = "EXTERNAL"});
+                               reply:text(base64.encode(session.from_host))
+                               session.sends2s(reply)
+                               session.external_auth = "attempting"
+                               return true
+                       end
+               end
+       end
+end, 150);
+
+local function s2s_external_auth(session, stanza)
+       local mechanism = stanza.attr.mechanism;
+
+       if not session.secure then
+               if mechanism == "EXTERNAL" then
+                       session.sends2s(build_reply("failure", "encryption-required"))
+               else
+                       session.sends2s(build_reply("failure", "invalid-mechanism"))
+               end
+               return true;
+       end
+
+       if mechanism ~= "EXTERNAL" or session.cert_chain_status ~= "valid" then
+               session.sends2s(build_reply("failure", "invalid-mechanism"))
+               return true;
+       end
+
+       local text = stanza[1]
+       if not text then
+               session.sends2s(build_reply("failure", "malformed-request"))
+               return true
+       end
+
+       -- Either the value is "=" and we've already verified the external
+       -- cert identity, or the value is a string and either matches the
+       -- from_host (
+
+       text = base64.decode(text)
+       if not text then
+               session.sends2s(build_reply("failure", "incorrect-encoding"))
+               return true;
+       end
+
+       if session.cert_identity_status == "valid" then
+               if text ~= "" and text ~= session.from_host then
+                       session.sends2s(build_reply("failure", "invalid-authzid"))
+                       return true
+               end
+       else
+               if text == "" then
+                       session.sends2s(build_reply("failure", "invalid-authzid"))
+                       return true
+               end
+
+               local cert = session.conn:socket():getpeercertificate()
+               if (cert_verify_identity(text, "xmpp-server", cert)) then
+                       session.cert_identity_status = "valid"
+               else
+                       session.cert_identity_status = "invalid"
+                       session.sends2s(build_reply("failure", "invalid-authzid"))
+                       return true
+               end
+       end
+
+       session.external_auth = "succeeded"
+
+       if not session.from_host then
+               session.from_host = text;
+       end
+       session.sends2s(build_reply("success"))
+
+       local domain = text ~= "" and text or session.from_host;
+       module:log("info", "Accepting SASL EXTERNAL identity from %s", domain);
+       s2s_make_authenticated(session, domain);
+       session:reset_stream();
+       return true
+end
+
 module:hook("stanza/urn:ietf:params:xml:ns:xmpp-sasl:auth", function(event)
        local session, stanza = event.origin, event.stanza;
+       if session.type == "s2sin_unauthed" then
+               return s2s_external_auth(session, stanza)
+       end
+
        if session.type ~= "c2s_unauthed" then return; end
 
        if session.sasl_handler and session.sasl_handler.selected then
                session.sasl_handler = nil; -- allow starting a new SASL negotiation before completing an old one
        end
        if not session.sasl_handler then
-               if anonymous_login then
-                       session.sasl_handler = new_sasl(module.host, anonymous_authentication_profile);
-               else
-                       session.sasl_handler = usermanager_get_sasl_handler(module.host);
-               end
+               session.sasl_handler = usermanager_get_sasl_handler(module.host, session);
        end
        local mechanism = stanza.attr.mechanism;
-       if anonymous_login then
-               if mechanism ~= "ANONYMOUS" then
-                       session.send(build_reply("failure", "invalid-mechanism"));
-                       return true;
-               end
-       elseif mechanism == "ANONYMOUS" then
-               session.send(build_reply("failure", "mechanism-too-weak"));
-               return true;
-       end
        if not session.secure and (secure_auth_only or (mechanism == "PLAIN" and not allow_unencrypted_plain_auth)) then
                session.send(build_reply("failure", "encryption-required"));
                return true;
@@ -150,24 +246,34 @@ module:hook("stream-features", function(event)
                if secure_auth_only and not origin.secure then
                        return;
                end
-               if anonymous_login then
-                       origin.sasl_handler = new_sasl(module.host, anonymous_authentication_profile);
-               else
-                       origin.sasl_handler = usermanager_get_sasl_handler(module.host);
-               end
-               features:tag("mechanisms", mechanisms_attr);
+               origin.sasl_handler = usermanager_get_sasl_handler(module.host, origin);
+               local mechanisms = st.stanza("mechanisms", mechanisms_attr);
                for mechanism in pairs(origin.sasl_handler:mechanisms()) do
                        if mechanism ~= "PLAIN" or origin.secure or allow_unencrypted_plain_auth then
-                               features:tag("mechanism"):text(mechanism):up();
+                               mechanisms:tag("mechanism"):text(mechanism):up();
                        end
                end
-               features:up();
+               if mechanisms[1] then features:add_child(mechanisms); end
        else
                features:tag("bind", bind_attr):tag("required"):up():up();
                features:tag("session", xmpp_session_attr):tag("optional"):up():up();
        end
 end);
 
+module:hook("s2s-stream-features", function(event)
+       local origin, features = event.origin, event.features;
+       if origin.secure and origin.type == "s2sin_unauthed" then
+               -- Offer EXTERNAL if chain is valid and either we didn't validate
+               -- the identity or it passed.
+               if origin.cert_chain_status == "valid" and origin.cert_identity_status ~= "invalid" then --TODO: Configurable
+                       module:log("debug", "Offering SASL EXTERNAL")
+                       features:tag("mechanisms", { xmlns = xmlns_sasl })
+                               :tag("mechanism"):text("EXTERNAL")
+                       :up():up();
+               end
+       end
+end);
+
 module:hook("iq/self/urn:ietf:params:xml:ns:xmpp-bind:bind", function(event)
        local origin, stanza = event.origin, event.stanza;
        local resource;
@@ -189,7 +295,10 @@ module:hook("iq/self/urn:ietf:params:xml:ns:xmpp-bind:bind", function(event)
        return true;
 end);
 
-module:hook("iq/self/urn:ietf:params:xml:ns:xmpp-session:session", function(event)
+local function handle_legacy_session(event)
        event.origin.send(st.reply(event.stanza));
        return true;
-end);
+end
+
+module:hook("iq/self/urn:ietf:params:xml:ns:xmpp-session:session", handle_legacy_session);
+module:hook("iq/host/urn:ietf:params:xml:ns:xmpp-session:session", handle_legacy_session);