diff options
Diffstat (limited to 'libs/web/luasrc/http/protocol/conditionals.lua')
| -rw-r--r-- | libs/web/luasrc/http/protocol/conditionals.lua | 153 |
1 files changed, 153 insertions, 0 deletions
diff --git a/libs/web/luasrc/http/protocol/conditionals.lua b/libs/web/luasrc/http/protocol/conditionals.lua new file mode 100644 index 0000000000..75e1f7b37c --- /dev/null +++ b/libs/web/luasrc/http/protocol/conditionals.lua @@ -0,0 +1,153 @@ +--[[ + +HTTP protocol implementation for LuCI - RFC2616 / 14.19, 14.24 - 14.28 +(c) 2008 Freifunk Leipzig / Jo-Philipp Wich <xm@leipzig.freifunk.net> + +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 http protocol implementation - HTTP/1.1 bits. +-- This class provides basic ETag handling and implements most of the +-- conditional HTTP/1.1 headers specified in RFC2616 Sct. 14.24 - 14.28 . +module("luci.http.protocol.conditionals", package.seeall) + +local date = require("luci.http.protocol.date") + + +--- Implement 14.19 / ETag. +-- @param stat A file.stat structure +-- @return String containing the generated tag suitable for ETag headers +function mk_etag( stat ) + if stat ~= nil then + return string.format( '"%x-%x-%x"', stat.ino, stat.size, stat.mtime ) + end +end + +--- 14.24 / If-Match +-- Test whether the given message object contains an "If-Match" header and +-- compare it against the given stat object. +-- @param req HTTP request message object +-- @param stat A file.stat object +-- @return Boolean indicating whether the precondition is ok +-- @return Alternative status code if the precondition failed +function if_match( req, stat ) + local h = req.headers + local etag = mk_etag( stat ) + + -- Check for matching resource + if type(h['If-Match']) == "string" then + for ent in h['If-Match']:gmatch("([^, ]+)") do + if ( ent == '*' or ent == etag ) and stat ~= nil then + return true + end + end + + return false, 412 + end + + return true +end + +--- 14.25 / If-Modified-Since +-- Test whether the given message object contains an "If-Modified-Since" header +-- and compare it against the given stat object. +-- @param req HTTP request message object +-- @param stat A file.stat object +-- @return Boolean indicating whether the precondition is ok +-- @return Alternative status code if the precondition failed +-- @return Table containing extra HTTP headers if the precondition failed +function if_modified_since( req, stat ) + local h = req.headers + + -- Compare mtimes + if type(h['If-Modified-Since']) == "string" then + local since = date.to_unix( h['If-Modified-Since'] ) + + if stat == nil or since < stat.mtime then + return true + end + + return false, 304, { + ["ETag"] = mk_etag( stat ); + ["Date"] = date.to_http( os.time() ); + ["Last-Modified"] = date.to_http( stat.mtime ) + } + end + + return true +end + +--- 14.26 / If-None-Match +-- Test whether the given message object contains an "If-None-Match" header and +-- compare it against the given stat object. +-- @param req HTTP request message object +-- @param stat A file.stat object +-- @return Boolean indicating whether the precondition is ok +-- @return Alternative status code if the precondition failed +-- @return Table containing extra HTTP headers if the precondition failed +function if_none_match( req, stat ) + local h = req.headers + local etag = mk_etag( stat ) + local method = req.env and req.env.REQUEST_METHOD or "GET" + + -- Check for matching resource + if type(h['If-None-Match']) == "string" then + for ent in h['If-None-Match']:gmatch("([^, ]+)") do + if ( ent == '*' or ent == etag ) and stat ~= nil then + if method == "GET" or method == "HEAD" then + return false, 304, { + ["ETag"] = etag; + ["Date"] = date.to_http( os.time() ); + ["Last-Modified"] = date.to_http( stat.mtime ) + } + else + return false, 412 + end + end + end + end + + return true +end + +--- 14.27 / If-Range +-- The If-Range header is currently not implemented due to the lack of general +-- byte range stuff in luci.http.protocol . This function will always return +-- false, 412 to indicate a failed precondition. +-- @param req HTTP request message object +-- @param stat A file.stat object +-- @return Boolean indicating whether the precondition is ok +-- @return Alternative status code if the precondition failed +function if_range( req, stat ) + -- Sorry, no subranges (yet) + return false, 412 +end + +--- 14.28 / If-Unmodified-Since +-- Test whether the given message object contains an "If-Unmodified-Since" +-- header and compare it against the given stat object. +-- @param req HTTP request message object +-- @param stat A file.stat object +-- @return Boolean indicating whether the precondition is ok +-- @return Alternative status code if the precondition failed +function if_unmodified_since( req, stat ) + local h = req.headers + + -- Compare mtimes + if type(h['If-Unmodified-Since']) == "string" then + local since = date.to_unix( h['If-Unmodified-Since'] ) + + if stat ~= nil and since <= stat.mtime then + return false, 412 + end + end + + return true +end |