add padding mode for DES, see #1179

test/testcrypt.lua

@@ -0,0 +1,24 @@
+local skynet = require "skynet"
+local crypt = require "skynet.crypt"
+
+local text = "hello world"
+local key = "12345678"
+
+local function desencode(key, text, padding)
+	local c = crypt.desencode(key, text, crypt.padding[padding or "iso7816_4"])
+	return crypt.base64encode(c)
+end
+
+local function desdecode(key, text, padding)
+	text = crypt.base64decode(text)
+	return crypt.desdecode(key, text, crypt.padding[padding or "iso7816_4"])
+end
+
+local etext = desencode(key, text)
+assert( etext == "KNugLrX23UcGtcVlk9y+LA==")
+assert(desdecode(key, etext) == text)
+
+local etext = desencode(key, text, "pkcs7")
+assert(desdecode(key, etext, "pkcs7") == text)
+
+skynet.start(skynet.exit)