applications/luci-app-commands/luasrc/controller/commands.lua

   1 -- Copyright 2012 Jo-Philipp Wich <jow@openwrt.org>
   2 -- Licensed to the public under the Apache License 2.0.
   3
   4 module("luci.controller.commands", package.seeall)
   5
   6 function index()
   7         entry({"admin", "system", "commands"}, firstchild(), _("Custom Commands"), 80)
   8         entry({"admin", "system", "commands", "dashboard"}, template("commands"), _("Dashboard"), 1)
   9         entry({"admin", "system", "commands", "config"}, cbi("commands"), _("Configure"), 2)
  10         entry({"admin", "system", "commands", "run"}, call("action_run"), nil, 3).leaf = true
  11         entry({"admin", "system", "commands", "download"}, call("action_download"), nil, 3).leaf = true
  12
  13         entry({"command"}, call("action_public"), nil, 1).leaf = true
  14 end
  15
  16 --- Decode a given string into arguments following shell quoting rules
  17 --- [[abc \def "foo\"bar" abc'def']] -> [[abc def]] [[foo"bar]] [[abcdef]]
  18 local function parse_args(str)
  19         local args = { }
  20
  21         local function isspace(c)
  22                 if c == 9 or c == 10 or c == 11 or c == 12 or c == 13 or c == 32 then
  23                         return c
  24                 end
  25         end
  26
  27         local function isquote(c)
  28                 if c == 34 or c == 39 or c == 96 then
  29                         return c
  30                 end
  31         end
  32
  33         local function isescape(c)
  34                 if c == 92 then
  35                         return c
  36                 end
  37         end
  38
  39         local function ismeta(c)
  40                 if c == 36 or c == 92 or c == 96 then
  41                         return c
  42                 end
  43         end
  44
  45         --- Convert given table of byte values into a Lua string and append it to
  46         --- the "args" table. Segment byte value sequence into chunks of 256 values
  47         --- to not trip over the parameter limit for string.char()
  48         local function putstr(bytes)
  49                 local chunks = { }
  50                 local csz = 256
  51                 local upk = unpack
  52                 local chr = string.char
  53                 local min = math.min
  54                 local len = #bytes
  55                 local off
  56
  57                 for off = 1, len, csz do
  58                         chunks[#chunks+1] = chr(upk(bytes, off, min(off + csz - 1, len)))
  59                 end
  60
  61                 args[#args+1] = table.concat(chunks)
  62         end
  63
  64         --- Scan substring defined by the indexes [s, e] of the string "str",
  65         --- perform unquoting and de-escaping on the fly and store the result in
  66         --- a table of byte values which is passed to putstr()
  67         local function unquote(s, e)
  68                 local off, esc, quote
  69                 local res = { }
  70
  71                 for off = s, e do
  72                         local byte = str:byte(off)
  73                         local q = isquote(byte)
  74                         local e = isescape(byte)
  75                         local m = ismeta(byte)
  76
  77                         if e then
  78                                 esc = true
  79                         elseif esc then
  80                                 if m then res[#res+1] = 92 end
  81                                 res[#res+1] = byte
  82                                 esc = false
  83                         elseif q and quote and q == quote then
  84                                 quote = nil
  85                         elseif q and not quote then
  86                                 quote = q
  87                         else
  88                                 if m then res[#res+1] = 92 end
  89                                 res[#res+1] = byte
  90                         end
  91                 end
  92
  93                 putstr(res)
  94         end
  95
  96         --- Find substring boundaries in "str". Ignore escaped or quoted
  97         --- whitespace, pass found start- and end-index for each substring
  98         --- to unquote()
  99         local off, esc, start, quote
 100         for off = 1, #str + 1 do
 101                 local byte = str:byte(off)
 102                 local q = isquote(byte)
 103                 local s = isspace(byte) or (off > #str)
 104                 local e = isescape(byte)
 105
 106                 if esc then
 107                         esc = false
 108                 elseif e then
 109                         esc = true
 110                 elseif q and quote and q == quote then
 111                         quote = nil
 112                 elseif q and not quote then
 113                         start = start or off
 114                         quote = q
 115                 elseif s and not quote then
 116                         if start then
 117                                 unquote(start, off - 1)
 118                                 start = nil
 119                         end
 120                 else
 121                         start = start or off
 122                 end
 123         end
 124
 125         --- If the "quote" is still set we encountered an unfinished string
 126         if quote then
 127                 unquote(start, #str)
 128         end
 129
 130         return args
 131 end
 132
 133 local function parse_cmdline(cmdid, args)
 134         local uci = require "luci.model.uci".cursor()
 135         if uci:get("luci", cmdid) == "command" then
 136                 local cmd = uci:get_all("luci", cmdid)
 137                 local argv = parse_args(cmd.command)
 138                 local i, v
 139
 140                 if cmd.param == "1" and args then
 141                         for i, v in ipairs(parse_args(luci.http.urldecode(args))) do
 142                                 argv[#argv+1] = v
 143                         end
 144                 end
 145
 146                 for i, v in ipairs(argv) do
 147                         if v:match("[^%w%.%-i/]") then
 148                                 argv[i] = '"%s"' % v:gsub('"', '\\"')
 149                         end
 150                 end
 151
 152                 return argv
 153         end
 154 end
 155
 156 function action_run(...)
 157         local fs   = require "nixio.fs"
 158         local argv = parse_cmdline(...)
 159         if argv then
 160                 local outfile = os.tmpname()
 161                 local errfile = os.tmpname()
 162
 163                 local rv = os.execute(table.concat(argv, " ") .. " >%s 2>%s" %{ outfile, errfile })
 164                 local stdout = fs.readfile(outfile, 1024 * 512) or ""
 165                 local stderr = fs.readfile(errfile, 1024 * 512) or ""
 166
 167                 fs.unlink(outfile)
 168                 fs.unlink(errfile)
 169
 170                 local binary = not not (stdout:match("[%z\1-\8\14-\31]"))
 171
 172                 luci.http.prepare_content("application/json")
 173                 luci.http.write_json({
 174                         command  = table.concat(argv, " "),
 175                         stdout   = not binary and stdout,
 176                         stderr   = stderr,
 177                         exitcode = rv,
 178                         binary   = binary
 179                 })
 180         else
 181                 luci.http.status(404, "No such command")
 182         end
 183 end
 184
 185 function action_download(...)
 186         local fs   = require "nixio.fs"
 187         local argv = parse_cmdline(...)
 188         if argv then
 189                 local fd = io.popen(table.concat(argv, " ") .. " 2>/dev/null")
 190                 if fd then
 191                         local chunk = fd:read(4096) or ""
 192                         local name
 193                         if chunk:match("[%z\1-\8\14-\31]") then
 194                                 luci.http.header("Content-Disposition", "attachment; filename=%s"
 195                                                  % fs.basename(argv[1]):gsub("%W+", ".") .. ".bin")
 196                                 luci.http.prepare_content("application/octet-stream")
 197                         else
 198                                 luci.http.header("Content-Disposition", "attachment; filename=%s"
 199                                                  % fs.basename(argv[1]):gsub("%W+", ".") .. ".txt")
 200                                 luci.http.prepare_content("text/plain")
 201                         end
 202
 203                         while chunk do
 204                                 luci.http.write(chunk)
 205                                 chunk = fd:read(4096)
 206                         end
 207
 208                         fd:close()
 209                 else
 210                         luci.http.status(500, "Failed to execute command")
 211                 end
 212         else
 213                 luci.http.status(404, "No such command")
 214         end
 215 end
 216
 217 function action_public(cmdid, args)
 218         local uci = require "luci.model.uci".cursor()
 219         if cmdid and
 220            uci:get("luci", cmdid) == "command" and
 221            uci:get("luci", cmdid, "public") == "1"
 222         then
 223                 action_download(cmdid, args)
 224         else
 225                 luci.http.status(403, "Access to command denied")
 226         end
 227 end