;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;
; WebSocket (6455) - ABNF
;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
extension-param = token [ "=" (token / quoted-string) ]
NZDIGIT       =  "1" / "2" / "3" / "4" / "5" / "6" / "7" / "8" / "9"
version = DIGIT / (NZDIGIT DIGIT) / ("1" DIGIT DIGIT) / ("2" DIGIT DIGIT)
base64-character = ALPHA / DIGIT / "+" / "/"

Sec-WebSocket-Key = base64-value-non-empty
Sec-WebSocket-Extensions = extension-list
Sec-WebSocket-Protocol-Client = token *(COMMA token)
Sec-WebSocket-Version-Client = version

base64-value-non-empty = (1*base64-data [ base64-padding ]) / base64-padding
base64-data      = 4base64-character
base64-padding   = (2base64-character "==") / (3base64-character "=")

extension-list = extension *(COMMA extension)
extension = extension-token *( ";" extension-param )
extension-token = registered-token
registered-token = token

Sec-WebSocket-Accept     = base64-value-non-empty
Sec-WebSocket-Protocol-Server = token
Sec-WebSocket-Version-Server = version *(COMMA version)

Sec-WebSocket-Version = version *(COMMA version)
Sec-WebSocket-Protocol = token *(COMMA token)