1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
|
--[[
Session authentication
(c) 2008 Steven Barth <steven@midlink.org>
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
$Id$
]]--
--- LuCI session library.
module("luci.sauth", package.seeall)
require("luci.util")
require("luci.sys")
require("luci.config")
local nixio = require "nixio", require "nixio.util"
local fs = require "nixio.fs"
luci.config.sauth = luci.config.sauth or {}
sessionpath = luci.config.sauth.sessionpath
sessiontime = tonumber(luci.config.sauth.sessiontime) or 15 * 60
--- 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
local function _read(id)
local blob = fs.readfile(sessionpath .. "/" .. id)
return blob
end
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 table
function write(id, data)
if not sane() then
prepare()
end
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
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)
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
end
|