-- mod_net_dovecotauth.lua -- -- Protocol spec: -- http://dovecot.org/doc/auth-protocol.txt -- -- Example postfix config: -- sudo postconf smtpd_sasl_path=inet:127.0.0.1:28484 -- sudo postconf smtpd_sasl_type=dovecot -- sudo postconf smtpd_sasl_auth_enable=yes module:set_global(); -- Imports local new_sasl = require "core.usermanager".get_sasl_handler; local user_exists = require "core.usermanager".user_exists; local base64 = require"util.encodings".base64; local dump = require"util.serialization".serialize; local pposix = require "util.pposix"; -- Config local default_vhost = module:get_option_string("dovecotauth_host", (next(hosts))); -- TODO Is there a better solution? local allow_master = module:get_option_boolean("dovecotauth_allow_master", false); -- Active sessions local sessions = {}; -- Session methods local new_session; do local sess = { }; local sess_mt = { __index = sess }; function new_session(conn) local s = { type = "?", conn = conn, buf = "", sasl = {} } function s:log(l, m, ...) return module:log(l, self.type..tonumber(tostring(self):match("%x+$"), 16)..": "..m, ...); end return setmetatable(s, sess_mt); end function sess:send(...) local data = table.concat({...}, "\t") .. "\n" -- self:log("debug", "SEND: %s", dump(ret)); return self.conn:write(data); end local mech_params = { ANONYMOUS = "anonymous"; PLAIN = "plaintext"; ["DIGEST-MD5"] = "mutual-auth"; ["SCRAM-SHA-1"] = "mutual-auth"; ["SCRAM-SHA-1-PLUS"] = "mutual-auth"; } function sess:handshake() self:send("VERSION", 1, 1); self:send("SPID", pposix.getpid()); self:send("CUID", tonumber(tostring(self):match"%x+$", 16)); for mech in pairs(self.g_sasl:mechanisms()) do self:send("MECH", mech, mech_params[mech]); end self:send("DONE"); end function sess:feed(data) -- TODO break this up a bit -- module:log("debug", "sess = %s", dump(self)); local buf = self.buf; buf = buf .. data; local line, eol = buf:match("(.-)\r?\n()") while line and line ~= "" do buf = buf:sub(eol); self.buf = buf; local part = line:gmatch("[^\t]+"); local command = part(); if command == "VERSION" then local major = tonumber(part()); local minor = tonumber(part()); if major ~= 1 then self:log("warn", "Wrong version, expected 1.1, got %s.%s", tostring(major), tostring(minor)); self.conn:close(); break; end elseif command == "CPID" then self.type = "C"; self.pid = part(); elseif command == "SPID" and allow_master then self.type = "M"; self.pid = part(); elseif command == "AUTH" and self.type ~= "?" then -- C: "AUTH" TAB TAB TAB service= [TAB ] local id = part() -- local sasl = self.sasl[id]; local mech = part(); if not sasl then -- TODO Should maybe initialize SASL handler after parsing the line? sasl = self.g_sasl:clean_clone(); self.sasl[id] = sasl; if not sasl:select(mech) then self:send("FAIL", id, "reason=invalid-mechanism"); self.sasl[id] = nil; sasl = false end end if sasl then local params = {}; -- Not used for anything yet for p in part do local k,v = p:match("^([^=]*)=(.*)$"); if k == "resp" then self:log("debug", "params = %s", dump(params)); v = base64.decode(v); local status, ret, err = sasl:process(v); self:log("debug", status); if status == "challenge" then self:send("CONT", id, base64.encode(ret)); elseif status == "failure" then self.sasl[id] = nil; self:send("FAIL", id, "reason="..tostring(err)); elseif status == "success" then self.sasl[id] = nil; self:send("OK", id, "user="..sasl.username, ret and "resp="..base64.encode(ret)); end break; -- resp MUST be the last param else params[k or p] = v or true; end end end elseif command == "USER" and self.type == "M" then -- FIXME Should this be on a separate listener? local id = part(); local user = part(); if user and user_exists(user, default_vhost) then self:send("USER", id); else self:send("NOTFOUND", id); end else self:log("warn", "Unhandled command %s", tostring(command)); self.conn:close(); break; end line, eol = buf:match("(.-)\r?\n()") end end end local listener = {} function listener.onconnect(conn) local s = new_session(conn); sessions[conn] = s; local g_sasl = new_sasl(default_vhost, s); s.g_sasl = g_sasl; s:handshake(); end function listener.onincoming(conn, data) local s = sessions[conn]; -- s:log("debug", "RECV %s", dump(data)); return s:feed(data); end function listener.ondisconnect(conn) sessions[conn] = nil; end function module.unload() for c in pairs(sessions) do c:close(); end end module:provides("net", { default_port = 28484; listener = listener; });