target = "https://www.rfc-editor.org/rfc/rfc9000#section-6.2"

# 6.2.  Handling Version Negotiation Packets
#
# Version Negotiation packets are designed to allow for functionality
# to be defined in the future that allows QUIC to negotiate the version
# of QUIC to use for a connection.  Future Standards Track
# specifications might change how implementations that support multiple
# versions of QUIC react to Version Negotiation packets received in
# response to an attempt to establish a connection using this version.
# 
# A client that supports only this version of QUIC MUST abandon the
# current connection attempt if it receives a Version Negotiation
# packet, with the following two exceptions.  A client MUST discard any
# Version Negotiation packet if it has received and successfully
# processed any other packet, including an earlier Version Negotiation
# packet.  A client MUST discard a Version Negotiation packet that
# lists the QUIC version selected by the client.
# 
# How to perform version negotiation is left as future work defined by
# future Standards Track specifications.  In particular, that future
# work will ensure robustness against version downgrade attacks; see
# Section 21.12.

[[spec]]
level = "MUST"
quote = '''
A client that supports only this version of QUIC MUST abandon the
current connection attempt if it receives a Version Negotiation
packet, with the following two exceptions.
'''

[[spec]]
level = "MUST"
quote = '''
A client MUST discard any
Version Negotiation packet if it has received and successfully
processed any other packet, including an earlier Version Negotiation
packet.
'''

[[spec]]
level = "MUST"
quote = '''
A client MUST discard a Version Negotiation packet that
lists the QUIC version selected by the client.
'''