diff options
-rw-r--r-- | util/paseto.lua | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/util/paseto.lua b/util/paseto.lua index 8b564c96..44210b1e 100644 --- a/util/paseto.lua +++ b/util/paseto.lua @@ -14,7 +14,18 @@ local b64url_rep = { ["+"] = "-", ["/"] = "_", ["="] = "", ["-"] = "+", ["_"] = local function b64url(data) return (s_gsub(base64_encode(data), "[+/=]", b64url_rep)); end + +local valid_tails = { + nil; -- Always invalid + "^.[AQgw]$"; -- b??????00 + "^..[AQgwEUk0IYo4Mcs8]$"; -- b????0000 +} + local function unb64url(data) + local rem = #data%4; + if data:sub(-1,-1) == "=" or rem == 1 or (rem > 1 and not data:sub(-rem):match(valid_tails[rem])) then + return nil; + end return base64_decode(s_gsub(data, "[-_]", b64url_rep).."=="); end |