The syscall package has been deprecated in favor of golang.org/x/sys.
Note that syscall is still used in some places because the following don't seem
to have an equivalent in unix package:
- syscall.SysProcIDMap
- syscall.Credential
Updates #214
PiperOrigin-RevId: 361332034
Previously, sending on an unconnected UDP socket would ignore the
SO_BINDTODEVICE option. Send on the configured interface when an UDP socket
is bound to an interface through setsockop SO_BINDTODEVICE.
Add packetimpact tests exercising UDP reads and writes with every combination
of bound/unbound, broadcast/multicast/unicast destination, and bound/not-bound
to device.
PiperOrigin-RevId: 354299670
Summary of the approach: the test runner will set up a few DUTs according to
a flag and pass all the test networks to the testbench. The testbench will only
reside in a single container. The testbench will put all the test networks into
a buffered channel which served as a semaphore and now the user can freely use
t.Parallel() in (sub)tests and the true parallelism will be determined by how
many DUTs are configured. Creating DUTs on demand is not supported yet, the
test author should determine the number of DUTs to be used statically.
Specifically in this change:
- Don't export any global variables about the test network in testbench.
- Sniffer only binds on the local interface because it will be possible to have
multiple interfaces to multiple DUTs in a single testbench container.
- Migrate existing tests to stop using global variables.
PiperOrigin-RevId: 343965962
Storing *testing.T on test helper structs is problematic when
subtests are used, because it is possible for nested tests to call
Fatal on parent test, which incorrect terminates the parent test.
For example
func TestOuter(t *testing.T) {
dut := NewDUT(t)
t.Run("first test", func(t *testing.T) {
dut.FallibleCall()
})
t.Run("second test", func(t *testing.T) {
dut.FallibleCall()
}
}
In the example above, assuming `FallibleCall` calls `t.Fatal` on the
`t` it holds, if `dut.FallibleCall` fails in "first test", it will
call `Fatal` on the parent `t`, quitting `TestOuter`. This is not a
behavior we want.
PiperOrigin-RevId: 323350241
Moved the function for generating a payload of random byets of a specified
length into the testbench package so that it's availbale for all tests to use.
Added a test case to the IPv4 ID uniqueness test which uses a payload length
of 512 bytes. This test case passes for gVisor currently, whereas the test case
with a small payload of 11 bytes fails because gVisor only assigns the ID field
if the IP payload is sufficiently large.
PiperOrigin-RevId: 316185097
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
Ayush Ranjan
Zeling Feng
Marina Ciocea
Jay Zhuang
Tony Gong
gVisor bot
Mithun Iyer
Bhasker Hariharan