From fef90c61c6186c113cfdb0bbcf53f4ca70f9741a Mon Sep 17 00:00:00 2001 From: Bhasker Hariharan Date: Wed, 15 Jul 2020 14:13:42 -0700 Subject: Fix minor bugs in a couple of interface IOCTLs. gVisor incorrectly returns the wrong ARP type for SIOGIFHWADDR. This breaks tcpdump as it tries to interpret the packets incorrectly. Similarly, SIOCETHTOOL is used by tcpdump to query interface properties which fails with an EINVAL since we don't implement it. For now change it to return EOPNOTSUPP to indicate that we don't support the query rather than return EINVAL. NOTE: ARPHRD types for link endpoints are distinct from NIC capabilities and NIC flags. In Linux all 3 exist eg. ARPHRD types are stored in dev->type field while NIC capabilities are more like the device features which can be queried using SIOCETHTOOL but not modified and NIC Flags are fields that can be modified from user space. eg. NIC status (UP/DOWN/MULTICAST/BROADCAST) etc. Updates #2746 PiperOrigin-RevId: 321436525 --- pkg/tcpip/stack/registration.go | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'pkg/tcpip/stack/registration.go') diff --git a/pkg/tcpip/stack/registration.go b/pkg/tcpip/stack/registration.go index 5cbc946b6..f260eeb7f 100644 --- a/pkg/tcpip/stack/registration.go +++ b/pkg/tcpip/stack/registration.go @@ -18,6 +18,7 @@ import ( "gvisor.dev/gvisor/pkg/sleep" "gvisor.dev/gvisor/pkg/tcpip" "gvisor.dev/gvisor/pkg/tcpip/buffer" + "gvisor.dev/gvisor/pkg/tcpip/header" "gvisor.dev/gvisor/pkg/waiter" ) @@ -436,6 +437,12 @@ type LinkEndpoint interface { // Wait will not block if the endpoint hasn't started any goroutines // yet, even if it might later. Wait() + + // ARPHardwareType returns the ARPHRD_TYPE of the link endpoint. + // + // See: + // https://github.com/torvalds/linux/blob/aa0c9086b40c17a7ad94425b3b70dd1fdd7497bf/include/uapi/linux/if_arp.h#L30 + ARPHardwareType() header.ARPHardwareType } // InjectableLinkEndpoint is a LinkEndpoint where inbound packets are -- cgit v1.2.3