feat: added action to validate ddos protection cookie

scripts/cookie.lua

@@ -0,0 +1,82 @@
+-- Copyright (C) 2013-2016 Jiale Zhi (calio), CloudFlare Inc.
+-- See RFC6265 http://tools.ietf.org/search/rfc6265
+-- require "luacov"
+
+local type          = type
+local byte          = string.byte
+local sub           = string.sub
+
+local EQUAL         = byte("=")
+local SEMICOLON     = byte(";")
+local SPACE         = byte(" ")
+local HTAB          = byte("\t")
+
+
+local _M = {}
+_M._VERSION = '0.01'
+
+
+function _M.get_cookie_table(text_cookie)
+    if type(text_cookie) ~= "string" then
+        return {}
+    end
+
+    local EXPECT_KEY    = 1
+    local EXPECT_VALUE  = 2
+    local EXPECT_SP     = 3
+
+    local n = 0
+    local len = #text_cookie
+
+    for i=1, len do
+        if byte(text_cookie, i) == SEMICOLON then
+            n = n + 1
+        end
+    end
+
+    local cookie_table  = {}
+
+    local state = EXPECT_SP
+    local i = 1
+    local j = 1
+    local key, value
+
+    while j <= len do
+        if state == EXPECT_KEY then
+            if byte(text_cookie, j) == EQUAL then
+                key = sub(text_cookie, i, j - 1)
+                state = EXPECT_VALUE
+                i = j + 1
+            end
+        elseif state == EXPECT_VALUE then
+            if byte(text_cookie, j) == SEMICOLON
+                    or byte(text_cookie, j) == SPACE
+                    or byte(text_cookie, j) == HTAB
+            then
+                value = sub(text_cookie, i, j - 1)
+                cookie_table[key] = value
+
+                key, value = nil, nil
+                state = EXPECT_SP
+                i = j + 1
+            end
+        elseif state == EXPECT_SP then
+            if byte(text_cookie, j) ~= SPACE
+                and byte(text_cookie, j) ~= HTAB
+            then
+                state = EXPECT_KEY
+                i = j
+                j = j - 1
+            end
+        end
+        j = j + 1
+    end
+
+    if key ~= nil and value == nil then
+        cookie_table[key] = sub(text_cookie, i)
+    end
+
+    return cookie_table
+end
+
+return _M