; Collected rules from RFC 7235
; https://tools.ietf.org/html/rfc7235

Authorization = credentials

Proxy-Authenticate = *( "," OWS ) challenge *( OWS ("," / challenge) )

Proxy-Authorization = credentials

WWW-Authenticate = *( "," OWS ) challenge *( OWS ("," / challenge) )

auth-param = token BWS "=" BWS ( token / quoted-string )

auth-scheme = token

challenge = auth-scheme [ 1*SP ( token68 / [ ( "," / auth-param ) *(OWS "," [ OWS auth-param ] ) ] ) ]

credentials = auth-scheme [ 1*SP ( token68 / [ ( "," / auth-param ) *( OWS "," [ OWS auth-param ] ) ] ) ]

token68 = 1*( ALPHA / DIGIT / "-" / "." / "_" / "~" / "+" / "/" ) *"="
