target = "https://www.rfc-editor.org/rfc/rfc9001#section-4.6.1"

# 4.6.1.  Enabling 0-RTT
#
# The TLS early_data extension in the NewSessionTicket message is
# defined to convey (in the max_early_data_size parameter) the amount
# of TLS 0-RTT data the server is willing to accept.  QUIC does not use
# TLS early data.  QUIC uses 0-RTT packets to carry early data.
# Accordingly, the max_early_data_size parameter is repurposed to hold
# a sentinel value 0xffffffff to indicate that the server is willing to
# accept QUIC 0-RTT data.  To indicate that the server does not accept
# 0-RTT data, the early_data extension is omitted from the
# NewSessionTicket.  The amount of data that the client can send in
# QUIC 0-RTT is controlled by the initial_max_data transport parameter
# supplied by the server.
# 
# Servers MUST NOT send the early_data extension with a
# max_early_data_size field set to any value other than 0xffffffff.  A
# client MUST treat receipt of a NewSessionTicket that contains an
# early_data extension with any other value as a connection error of
# type PROTOCOL_VIOLATION.
# 
# A client that wishes to send 0-RTT packets uses the early_data
# extension in the ClientHello message of a subsequent handshake; see
# Section 4.2.10 of [TLS13].  It then sends application data in 0-RTT
# packets.
# 
# A client that attempts 0-RTT might also provide an address validation
# token if the server has sent a NEW_TOKEN frame; see Section 8.1 of
# [QUIC-TRANSPORT].

[[spec]]
level = "MUST"
quote = '''
Servers MUST NOT send the early_data extension with a
max_early_data_size field set to any value other than 0xffffffff.
'''

[[spec]]
level = "MUST"
quote = '''
A
client MUST treat receipt of a NewSessionTicket that contains an
early_data extension with any other value as a connection error of
type PROTOCOL_VIOLATION.
'''