libs/web: rework luci.sauth

[project/luci.git] / libs / web / luasrc / sauth.lua

diff --git a/libs/web/luasrc/sauth.lua b/libs/web/luasrc/sauth.lua
index e5cb178..32f172d 100644 (file)
--- a/libs/web/luasrc/sauth.lua
+++ b/libs/web/luasrc/sauth.lua
@@ -15,7 +15,6 @@ $Id$
 
 --- LuCI session library.
 module("luci.sauth", package.seeall)
-require("luci.fs")
 require("luci.util")
 require("luci.sys")
 require("luci.config")
@@ -27,84 +26,102 @@ luci.config.sauth = luci.config.sauth or {}
 sessionpath = luci.config.sauth.sessionpath
 sessiontime = tonumber(luci.config.sauth.sessiontime) or 15 * 60
 
---- Manually clean up expired sessions.
-function clean()
-       local now   = os.time()
-       local files = luci.fs.dir(sessionpath)
-       
-       if not files then
-               return nil
-       end
-       
-       for i, file in pairs(files) do
-               local fname = sessionpath .. "/" .. file
-               local stat = luci.fs.stat(fname)
-               if stat and stat.type == "reg" and stat.mtime + sessiontime < now then
-                       luci.fs.unlink(fname)
-               end 
-       end
-end
-
 --- Prepare session storage by creating the session directory.
 function prepare()
        fs.mkdir(sessionpath, 700)
-        
        if not sane() then
                error("Security Exception: Session path is not sane!")
        end
 end
 
---- Read a session and return its content.
--- @param id   Session identifier
--- @return             Session data
-function read(id)
-       if not id then
-               return
-       end
-       if not id:match("^%w+$") then
-               error("Session ID is not sane!")
-       end
-       clean()
-       if not sane(sessionpath .. "/" .. id) then
-               return
-       end
-       luci.fs.utime(sessionpath .. "/" .. id)
-       return luci.fs.readfile(sessionpath .. "/" .. id)
+local function _read(id)
+       local blob = fs.readfile(sessionpath .. "/" .. id)
+       return blob
 end
 
-
---- Check whether Session environment is sane.
--- @return Boolean status
-function sane(file)
-       return luci.sys.process.info("uid")
-                       == luci.fs.stat(file or sessionpath, "uid")
-               and luci.fs.stat(file or sessionpath, "modestr")
-                       == (file and "rw-------" or "rwx------")
+local function _write(id, data)
+       local f = nixio.open(sessionpath .. "/" .. id, "w", 600)
+       f:writeall(data)
+       f:close()
 end
 
+local function _checkid(id)
+       return not not (id and #id == 32 and id:match("^[a-fA-F0-9]+$"))
+end
 
 --- Write session data to a session file.
 -- @param id   Session identifier
--- @param data Session data
+-- @param data Session data table
 function write(id, data)
        if not sane() then
                prepare()
        end
-       if not id:match("^%w+$") then
-               error("Session ID is not sane!")
+
+       assert(_checkid(id), "Security Exception: Session ID is invalid!")
+       assert(type(data) == "table", "Security Exception: Session data invalid!")
+
+       data.atime = luci.sys.uptime()
+
+       _write(id, luci.util.get_bytecode(data))
+end
+
+--- Read a session and return its content.
+-- @param id   Session identifier
+-- @return             Session data table or nil if the given id is not found
+function read(id)
+       if not id or #id == 0 then
+               return nil
        end
-       
-       local f = nixio.open(sessionpath .. "/" .. id, "w", 600)
-       f:writeall(data)
-       f:close()
+
+       assert(_checkid(id), "Security Exception: Session ID is invalid!")
+
+       if not sane(sessionpath .. "/" .. id) then
+               return nil
+       end
+
+       local blob = _read(id)
+       local func = loadstring(blob)
+       setfenv(func, {})
+
+       local sess = func()
+       assert(type(sess) == "table", "Session data invalid!")
+
+       if sess.atime and sess.atime + sessiontime < luci.sys.uptime() then
+               kill(id)
+               return nil
+       end
+
+       -- refresh atime in session
+       write(id, sess)
+
+       return sess
 end
 
+--- Check whether Session environment is sane.
+-- @return Boolean status
+function sane(file)
+       return luci.sys.process.info("uid")
+                       == fs.stat(file or sessionpath, "uid")
+               and fs.stat(file or sessionpath, "modestr")
+                       == (file and "rw-------" or "rwx------")
+end
 
 --- Kills a session
 -- @param id   Session identifier
 function kill(id)
-       if not id:match("^%w+$") then
-               error("Session ID is not sane!")
+       assert(_checkid(id), "Security Exception: Session ID is invalid!")
+       fs.unlink(sessionpath .. "/" .. id)
+end
+
+--- Remove all expired session data files
+function reap()
+       if sane() then
+               local id
+               for id in nixio.fs.dir(sessionpath) do
+                       if _checkid(id) then
+                               -- reading the session will kill it if it is expired
+                               read(id)
+                       end
+               end
        end
-       luci.fs.unlink(sessionpath .. "/" .. id)
-end
\ No newline at end of file
+end