Reorganize the Connection types such that the defined types no longer expose
the lower-level functions SendFrame and CreateFrame. These methods are still
exported on the underlying Connection type, and thus can be accessed via a
type-cast. In future, defined types should have one or more type-safe versions
of the send() method on Connection, e.g. UDPIPv4 has Send() which allows the UDP
header to be overridden and SendIP() which allows both the IPv4 and UDP headers
to be modified.
testbench.Connection gets a SendFrameStateless method which sends frames
without updating the state of any of the layers. This should be used when
sending out-of-band control messages such as ICMP messages, as using the
normal Send method can result in errors when attempting to update the TCP
state using an ICMP packet.
Also remove the localAddr field of testbench.Connection and instead compute
it on the fly as needed for UDPIPv4 and TCPIPv4.
PiperOrigin-RevId: 315969714
- Always split segments larger than MSS.
Currently, we base the segment split decision as a function of the
send congestion window and MSS, which could be greater than the MSS
advertised by remote.
- While splitting segments, ensure the PSH flag is reset when there
are segments that are queued to be sent.
- With TCP_CORK, hold up segments up until MSS. Fix a bug in computing
available send space before attempting to coalesce segments.
Fixes#2832
PiperOrigin-RevId: 314802928
Rather than have a struct for the state of each type of connection, such as
TCP/IPv4, UDP/IPv4, TCP/IPv6, etc, have a state for each layer, such as UDP,
TCP, IPv4, IPv6. Those states can be composed into connections.
Tested:
Existing unit tests still pass/fail as expected.
PiperOrigin-RevId: 306703180
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Mithun Iyer
Eyal Soha