Support SO_BINDTODEVICE in ICMP sockets

Adds support for the SO_BINDTODEVICE socket option in ICMP sockets with an
accompanying packetimpact test to exercise use of this socket option.

Adds a unit test to exercise the NIC selection logic introduced by this change.
The remaining unit tests for ICMP sockets need to be added in a subsequent CL.
See https://gvisor.dev/issues/5623 for the list of remaining unit tests.

Adds a "timeout" field to PacketimpactTestInfo, necessary due to the long
runtime of the newly added packetimpact test.

Fixes #5678
Fixes #4896
Updates #5623
Updates #5681
Updates #5763
Updates #5956
Updates #5966
Updates #5967

PiperOrigin-RevId: 376271581

1 files changed, 21 insertions, 1 deletions

diff --git a/test/packetimpact/testbench/testbench.go b/test/packetimpact/testbench/testbench.go
index 37d02365a..d0efbcc08 100644
--- a/test/packetimpact/testbench/testbench.go
+++ b/test/packetimpact/testbench/testbench.go
@@ -57,11 +57,21 @@ type DUTUname struct {
 	OperatingSystem string
 }
 
-// IsLinux returns true if we are running natively on Linux.
+// IsLinux returns true if the DUT is running Linux.
 func (n *DUTUname) IsLinux() bool {
 	return Native && n.OperatingSystem == "GNU/Linux"
 }
 
+// IsGvisor returns true if the DUT is running gVisor.
+func (*DUTUname) IsGvisor() bool {
+	return !Native
+}
+
+// IsFuchsia returns true if the DUT is running Fuchsia.
+func (n *DUTUname) IsFuchsia() bool {
+	return Native && n.OperatingSystem == "Fuchsia"
+}
+
 // DUTTestNet describes the test network setup on dut and how the testbench
 // should connect with an existing DUT.
 type DUTTestNet struct {
@@ -99,6 +109,16 @@ type DUTTestNet struct {
 	POSIXServerPort uint16
 }
 
+// SubnetBroadcast returns the test network's subnet broadcast address.
+func (n *DUTTestNet) SubnetBroadcast() net.IP {
+	addr := append([]byte(nil), n.RemoteIPv4...)
+	mask := net.CIDRMask(n.IPv4PrefixLength, net.IPv4len*8)
+	for i := range addr {
+		addr[i] |= ^mask[i]
+	}
+	return addr
+}
+
 // registerFlags defines flags and associates them with the package-level
 // exported variables above. It should be called by tests in their init
 // functions.