libs/lucid-http/luasrc/lucid/http/server.lua

   1 --[[
   2 LuCId HTTP-Slave
   3 (c) 2009 Steven Barth <steven@midlink.org>
   4
   5 Licensed under the Apache License, Version 2.0 (the "License");
   6 you may not use this file except in compliance with the License.
   7 You may obtain a copy of the License at
   8
   9         http://www.apache.org/licenses/LICENSE-2.0
  10
  11 $Id$
  12 ]]--
  13
  14 local ipairs, pairs = ipairs, pairs
  15 local tostring, tonumber = tostring, tonumber
  16 local pcall, assert, type = pcall, assert, type
  17 local set_memory_limit = set_memory_limit
  18
  19 local os = require "os"
  20 local nixio = require "nixio"
  21 local util = require "luci.util"
  22 local ltn12 = require "luci.ltn12"
  23 local proto = require "luci.http.protocol"
  24 local table = require "table"
  25 local date = require "luci.http.protocol.date"
  26
  27 --- HTTP Daemon
  28 -- @cstyle instance
  29 module "luci.lucid.http.server"
  30
  31 VERSION = "1.0"
  32
  33 statusmsg = {
  34         [200] = "OK",
  35         [206] = "Partial Content",
  36         [301] = "Moved Permanently",
  37         [302] = "Found",
  38         [304] = "Not Modified",
  39         [400] = "Bad Request",
  40         [401] = "Unauthorized",
  41         [403] = "Forbidden",
  42         [404] = "Not Found",
  43         [405] = "Method Not Allowed",
  44         [408] = "Request Time-out",
  45         [411] = "Length Required",
  46         [412] = "Precondition Failed",
  47         [416] = "Requested range not satisfiable",
  48         [500] = "Internal Server Error",
  49         [503] = "Server Unavailable",
  50 }
  51
  52 --- Create a new IO resource response.
  53 -- @class function
  54 -- @param fd File descriptor
  55 -- @param len Length of data
  56 -- @return IO resource
  57 IOResource = util.class()
  58
  59 function IOResource.__init__(self, fd, len)
  60         self.fd, self.len = fd, len
  61 end
  62
  63
  64 --- Create a server handler.
  65 -- @class function
  66 -- @param name Name
  67 -- @return Handler
  68 Handler = util.class()
  69
  70 function Handler.__init__(self, name)
  71         self.name = name or tostring(self)
  72 end
  73
  74 --- Create a failure reply.
  75 -- @param code HTTP status code
  76 -- @param msg Status message
  77 -- @return status code, header table, response source
  78 function Handler.failure(self, code, msg)
  79         return code, { ["Content-Type"] = "text/plain" }, ltn12.source.string(msg)
  80 end
  81
  82 --- Add an access restriction.
  83 -- @param restriction Restriction specification
  84 function Handler.restrict(self, restriction)
  85         if not self.restrictions then
  86                 self.restrictions = {restriction}
  87         else
  88                 self.restrictions[#self.restrictions+1] = restriction
  89         end
  90 end
  91
  92 --- Enforce access restrictions.
  93 -- @param request Request object
  94 -- @return nil or HTTP statuscode, table of headers, response source
  95 function Handler.checkrestricted(self, request)
  96         if not self.restrictions then
  97                 return
  98         end
  99
 100         local localif, user, pass
 101
 102         for _, r in ipairs(self.restrictions) do
 103                 local stat = true
 104                 if stat and r.interface then    -- Interface restriction
 105                         if not localif then
 106                                 for _, v in ipairs(request.server.interfaces) do
 107                                         if v.addr == request.env.SERVER_ADDR then
 108                                                 localif = v.name
 109                                                 break
 110                                         end
 111                                 end
 112                         end
 113
 114                         if r.interface ~= localif then
 115                                 stat = false
 116                         end
 117                 end
 118
 119                 if stat and r.user then -- User restriction
 120                         local rh, pwe
 121                         if not user then
 122                                 rh = (request.headers.Authorization or ""):match("Basic (.*)")
 123                                 rh = rh and nixio.bin.b64decode(rh) or ""
 124                                 user, pass = rh:match("(.*):(.*)")
 125                                 pass = pass or ""
 126                         end
 127                         pwe = nixio.getsp and nixio.getsp(r.user) or nixio.getpw(r.user)
 128                         local pwh = (user == r.user) and pwe and (pwe.pwdp or pwe.passwd)
 129                         if not pwh or #pwh < 1 or nixio.crypt(pass, pwh) ~= pwh then
 130                                 stat = false
 131                         end
 132                 end
 133
 134                 if stat then
 135                         return
 136                 end
 137         end
 138
 139         return 401, {
 140                 ["WWW-Authenticate"] = ('Basic realm=%q'):format(self.name),
 141                 ["Content-Type"] = 'text/plain'
 142         }, ltn12.source.string("Unauthorized")
 143 end
 144
 145 --- Process a request.
 146 -- @param request Request object
 147 -- @param sourcein Request data source
 148 -- @return HTTP statuscode, table of headers, response source
 149 function Handler.process(self, request, sourcein)
 150         local stat, code, hdr, sourceout
 151
 152         local stat, code, msg = self:checkrestricted(request)
 153         if stat then    -- Access Denied
 154                 return stat, code, msg
 155         end
 156
 157         -- Detect request Method
 158         local hname = "handle_" .. request.env.REQUEST_METHOD
 159         if self[hname] then
 160                 -- Run the handler
 161                 stat, code, hdr, sourceout = pcall(self[hname], self, request, sourcein)
 162
 163                 -- Check for any errors
 164                 if not stat then
 165                         return self:failure(500, code)
 166                 end
 167         else
 168                 return self:failure(405, statusmsg[405])
 169         end
 170
 171         return code, hdr, sourceout
 172 end
 173
 174
 175 --- Create a Virtual Host.
 176 -- @class function
 177 -- @return Virtual Host
 178 VHost = util.class()
 179
 180 function VHost.__init__(self)
 181         self.handlers = {}
 182 end
 183
 184 --- Process a request and invoke the appropriate handler.
 185 -- @param request Request object
 186 -- @param ... Additional parameters passed to the handler
 187 -- @return HTTP statuscode, table of headers, response source
 188 function VHost.process(self, request, ...)
 189         local handler
 190         local hlen = -1
 191         local uri = request.env.SCRIPT_NAME
 192         local sc = ("/"):byte()
 193
 194         -- SCRIPT_NAME
 195         request.env.SCRIPT_NAME = ""
 196
 197         -- Call URI part
 198         request.env.PATH_INFO = uri
 199
 200         for k, h in pairs(self.handlers) do
 201                 if #k > hlen then
 202                         if uri == k or (uri:sub(1, #k) == k and uri:byte(#k+1) == sc) then
 203                                 handler = h
 204                                 hlen = #k
 205                                 request.env.SCRIPT_NAME = k
 206                                 request.env.PATH_INFO   = uri:sub(#k+1)
 207                         end
 208                 end
 209         end
 210
 211         if handler then
 212                 return handler:process(request, ...)
 213         else
 214                 return 404, nil, ltn12.source.string("No such handler")
 215         end
 216 end
 217
 218 --- Get a list of registered handlers.
 219 -- @return Table of handlers
 220 function VHost.get_handlers(self)
 221         return self.handlers
 222 end
 223
 224 --- Register handler with a given URI prefix.
 225 -- @oaram match URI prefix
 226 -- @param handler Handler object
 227 function VHost.set_handler(self, match, handler)
 228         self.handlers[match] = handler
 229 end
 230
 231 -- Remap IPv6-IPv4-compatibility addresses back to IPv4 addresses.
 232 local function remapipv6(adr)
 233         local map = "::ffff:"
 234         if adr:sub(1, #map) == map then
 235                 return adr:sub(#map+1)
 236         else
 237                 return adr
 238         end
 239 end
 240
 241 -- Create a source that decodes chunked-encoded data from a socket.
 242 local function chunksource(sock, buffer)
 243         buffer = buffer or ""
 244         return function()
 245                 local output
 246                 local _, endp, count = buffer:find("^([0-9a-fA-F]+);?.-\r\n")
 247                 while not count and #buffer <= 1024 do
 248                         local newblock, code = sock:recv(1024 - #buffer)
 249                         if not newblock then
 250                                 return nil, code
 251                         end
 252                         buffer = buffer .. newblock
 253                         _, endp, count = buffer:find("^([0-9a-fA-F]+);?.-\r\n")
 254                 end
 255                 count = tonumber(count, 16)
 256                 if not count then
 257                         return nil, -1, "invalid encoding"
 258                 elseif count == 0 then
 259                         return nil
 260                 elseif count + 2 <= #buffer - endp then
 261                         output = buffer:sub(endp+1, endp+count)
 262                         buffer = buffer:sub(endp+count+3)
 263                         return output
 264                 else
 265                         output = buffer:sub(endp+1, endp+count)
 266                         buffer = ""
 267                         if count - #output > 0 then
 268                                 local remain, code = sock:recvall(count-#output)
 269                                 if not remain then
 270                                         return nil, code
 271                                 end
 272                                 output = output .. remain
 273                                 count, code = sock:recvall(2)
 274                         else
 275                                 count, code = sock:recvall(count+2-#buffer+endp)
 276                         end
 277                         if not count then
 278                                 return nil, code
 279                         end
 280                         return output
 281                 end
 282         end
 283 end
 284
 285 -- Create a sink that chunk-encodes data and writes it on a given socket.
 286 local function chunksink(sock)
 287         return function(chunk, err)
 288                 if not chunk then
 289                         return sock:writeall("0\r\n\r\n")
 290                 else
 291                         return sock:writeall(("%X\r\n%s\r\n"):format(#chunk, tostring(chunk)))
 292                 end
 293         end
 294 end
 295
 296
 297 --- Create a server object.
 298 -- @class function
 299 -- @return Server object
 300 Server = util.class()
 301
 302 function Server.__init__(self)
 303         self.vhosts = {}
 304 end
 305
 306 --- Get a list of registered virtual hosts.
 307 -- @return Table of virtual hosts
 308 function Server.get_vhosts(self)
 309         return self.vhosts
 310 end
 311
 312 --- Register a virtual host with a given name.
 313 -- @param name Hostname
 314 -- @param vhost Virtual host object
 315 function Server.set_vhost(self, name, vhost)
 316         self.vhosts[name] = vhost
 317 end
 318
 319 --- Send a fatal error message to given client and close the connection.
 320 -- @param client Client socket
 321 -- @param code HTTP status code
 322 -- @param msg status message
 323 function Server.error(self, client, code, msg)
 324         hcode = tostring(code)
 325
 326         client:writeall( "HTTP/1.0 " .. hcode .. " " ..
 327          statusmsg[code] .. "\r\n" )
 328         client:writeall( "Connection: close\r\n" )
 329         client:writeall( "Content-Type: text/plain\r\n\r\n" )
 330
 331         if msg then
 332                 client:writeall( "HTTP-Error " .. code .. ": " .. msg .. "\r\n" )
 333         end
 334
 335         client:close()
 336 end
 337
 338 local hdr2env = {
 339         ["Content-Length"] = "CONTENT_LENGTH",
 340         ["Content-Type"] = "CONTENT_TYPE",
 341         ["Content-type"] = "CONTENT_TYPE",
 342         ["Accept"] = "HTTP_ACCEPT",
 343         ["Accept-Charset"] = "HTTP_ACCEPT_CHARSET",
 344         ["Accept-Encoding"] = "HTTP_ACCEPT_ENCODING",
 345         ["Accept-Language"] = "HTTP_ACCEPT_LANGUAGE",
 346         ["Connection"] = "HTTP_CONNECTION",
 347         ["Cookie"] = "HTTP_COOKIE",
 348         ["Host"] = "HTTP_HOST",
 349         ["Referer"] = "HTTP_REFERER",
 350         ["User-Agent"] = "HTTP_USER_AGENT"
 351 }
 352
 353 --- Parse the request headers and prepare the environment.
 354 -- @param source line-based input source
 355 -- @return Request object
 356 function Server.parse_headers(self, source)
 357         local env = {}
 358         local req = {env = env, headers = {}}
 359         local line, err
 360
 361         repeat  -- Ignore empty lines
 362                 line, err = source()
 363                 if not line then
 364                         return nil, err
 365                 end
 366         until #line > 0
 367
 368         env.REQUEST_METHOD, env.REQUEST_URI, env.SERVER_PROTOCOL =
 369                 line:match("^([A-Z]+) ([^ ]+) (HTTP/1%.[01])$")
 370
 371         if not env.REQUEST_METHOD then
 372                 return nil, "invalid magic"
 373         end
 374
 375         local key, envkey, val
 376         repeat
 377                 line, err = source()
 378                 if not line then
 379                         return nil, err
 380                 elseif #line > 0 then
 381                         key, val = line:match("^([%w-]+)%s?:%s?(.*)")
 382                         if key then
 383                                 req.headers[key] = val
 384                                 envkey = hdr2env[key]
 385                                 if envkey then
 386                                         env[envkey] = val
 387                                 end
 388                         else
 389                                 return nil, "invalid header line"
 390                         end
 391                 else
 392                         break
 393                 end
 394         until false
 395
 396         env.SCRIPT_NAME, env.QUERY_STRING = env.REQUEST_URI:match("([^?]*)%??(.*)")
 397         return req
 398 end
 399
 400 --- Handle a new client connection.
 401 -- @param client client socket
 402 -- @param env superserver environment
 403 function Server.process(self, client, env)
 404         local sourcein  = function() end
 405         local sourcehdr = client:linesource()
 406         local sinkout
 407         local buffer
 408
 409         local close = false
 410         local stat, code, msg, message, err
 411
 412         env.config.memlimit = tonumber(env.config.memlimit)
 413         if env.config.memlimit and set_memory_limit then
 414                 set_memory_limit(env.config.memlimit)
 415         end
 416
 417         client:setsockopt("socket", "rcvtimeo", 5)
 418         client:setsockopt("socket", "sndtimeo", 5)
 419
 420         repeat
 421                 -- parse headers
 422                 message, err = self:parse_headers(sourcehdr)
 423
 424                 -- any other error
 425                 if not message or err then
 426                         if err == 11 then       -- EAGAIN
 427                                 break
 428                         else
 429                                 return self:error(client, 400, err)
 430                         end
 431                 end
 432
 433                 -- Prepare sources and sinks
 434                 buffer = sourcehdr(true)
 435                 sinkout = client:sink()
 436                 message.server = env
 437
 438                 if client:is_tls_socket() then
 439                         message.env.HTTPS = "on"
 440                 end
 441
 442                 -- Addresses
 443                 message.env.REMOTE_ADDR = remapipv6(env.host)
 444                 message.env.REMOTE_PORT = env.port
 445
 446                 local srvaddr, srvport = client:getsockname()
 447                 message.env.SERVER_ADDR = remapipv6(srvaddr)
 448                 message.env.SERVER_PORT = srvport
 449
 450                 -- keep-alive
 451                 if message.env.SERVER_PROTOCOL == "HTTP/1.1" then
 452                         close = (message.env.HTTP_CONNECTION == "close")
 453                 else
 454                         close = not message.env.HTTP_CONNECTION
 455                                 or message.env.HTTP_CONNECTION == "close"
 456                 end
 457
 458                 -- Uncomment this to disable keep-alive
 459                 close = close or env.config.nokeepalive
 460
 461                 if message.env.REQUEST_METHOD == "GET"
 462                 or message.env.REQUEST_METHOD == "HEAD" then
 463                         -- Be happy
 464
 465                 elseif message.env.REQUEST_METHOD == "POST" then
 466                         -- If we have a HTTP/1.1 client and an Expect: 100-continue header
 467                         -- respond with HTTP 100 Continue message
 468                         if message.env.SERVER_PROTOCOL == "HTTP/1.1"
 469                         and message.headers.Expect == '100-continue' then
 470                                 client:writeall("HTTP/1.1 100 Continue\r\n\r\n")
 471                         end
 472
 473                         if message.headers['Transfer-Encoding'] and
 474                          message.headers['Transfer-Encoding'] ~= "identity" then
 475                                 sourcein = chunksource(client, buffer)
 476                                 buffer = nil
 477                         elseif message.env.CONTENT_LENGTH then
 478                                 local len = tonumber(message.env.CONTENT_LENGTH)
 479                                 if #buffer >= len then
 480                                         sourcein = ltn12.source.string(buffer:sub(1, len))
 481                                         buffer = buffer:sub(len+1)
 482                                 else
 483                                         sourcein = ltn12.source.cat(
 484                                                 ltn12.source.string(buffer),
 485                                                 client:blocksource(nil, len - #buffer)
 486                                         )
 487                                 end
 488                         else
 489                                 return self:error(client, 411, statusmsg[411])
 490                         end
 491
 492                         close = true
 493                 else
 494                         return self:error(client, 405, statusmsg[405])
 495                 end
 496
 497
 498                 local host = self.vhosts[message.env.HTTP_HOST] or self.vhosts[""]
 499                 if not host then
 500                         return self:error(client, 404, "No virtual host found")
 501                 end
 502
 503                 local code, headers, sourceout = host:process(message, sourcein)
 504                 headers = headers or {}
 505
 506                 -- Post process response
 507                 if sourceout then
 508                         if util.instanceof(sourceout, IOResource) then
 509                                 if not headers["Content-Length"] then
 510                                         headers["Content-Length"] = sourceout.len
 511                                 end
 512                         end
 513                         if not headers["Content-Length"] and not close then
 514                                 if message.env.SERVER_PROTOCOL == "HTTP/1.1" then
 515                                         headers["Transfer-Encoding"] = "chunked"
 516                                         sinkout = chunksink(client)
 517                                 else
 518                                         close = true
 519                                 end
 520                         end
 521                 elseif message.env.REQUEST_METHOD ~= "HEAD" then
 522                         headers["Content-Length"] = 0
 523                 end
 524
 525                 if close then
 526                         headers["Connection"] = "close"
 527                 elseif message.env.SERVER_PROTOCOL == "HTTP/1.0" then
 528                         headers["Connection"] = "Keep-Alive"
 529                 end
 530
 531                 headers["Date"] = date.to_http(os.time())
 532                 local header = {
 533                         message.env.SERVER_PROTOCOL .. " " .. tostring(code) .. " "
 534                                 .. statusmsg[code],
 535                         "Server: LuCId-HTTPd/" .. VERSION
 536                 }
 537
 538
 539                 for k, v in pairs(headers) do
 540                         if type(v) == "table" then
 541                                 for _, h in ipairs(v) do
 542                                         header[#header+1] = k .. ": " .. h
 543                                 end
 544                         else
 545                                 header[#header+1] = k .. ": " .. v
 546                         end
 547                 end
 548
 549                 header[#header+1] = ""
 550                 header[#header+1] = ""
 551
 552                 -- Output
 553                 stat, code, msg = client:writeall(table.concat(header, "\r\n"))
 554
 555                 if sourceout and stat then
 556                         if util.instanceof(sourceout, IOResource) then
 557                                 if not headers["Transfer-Encoding"] then
 558                                         stat, code, msg = sourceout.fd:copyz(client, sourceout.len)
 559                                         sourceout = nil
 560                                 else
 561                                         sourceout = sourceout.fd:blocksource(nil, sourceout.len)
 562                                 end
 563                         end
 564
 565                         if sourceout then
 566                                 stat, msg = ltn12.pump.all(sourceout, sinkout)
 567                         end
 568                 end
 569
 570
 571                 -- Write errors
 572                 if not stat then
 573                         if msg then
 574                                 nixio.syslog("err", "Error sending data to " .. env.host ..
 575                                         ": " .. msg .. "\n")
 576                         end
 577                         break
 578                 end
 579
 580                 if buffer then
 581                         sourcehdr(buffer)
 582                 end
 583         until close
 584
 585         client:shutdown()
 586         client:close()
 587 end