diff options
| author | Ghanan Gowripalan <ghanan@google.com> | 2020-08-24 12:27:01 -0700 |
|---|---|---|
| committer | Andrei Vagin <avagin@gmail.com> | 2020-09-09 17:53:10 -0700 |
| commit | 901de6dc776c00bbdd60c12e800c6b10839b1466 (patch) | |
| tree | 6daeeac2e21847cb5304380d5d0516e1a929c464 /pkg/tcpip/stack/nic.go | |
| parent | 78c8c9e4c8a47818df14aac192a33a0f7b9f9006 (diff) | |
Consider loopback bound to all addresses in subnet
When a loopback interface is configurd with an address and associated
subnet, the loopback should treat all addresses in that subnet as an
address it owns.
This is mimicking linux behaviour as seen below:
```
$ ip addr show dev lo
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group ...
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
$ ping 192.0.2.1
PING 192.0.2.1 (192.0.2.1) 56(84) bytes of data.
^C
--- 192.0.2.1 ping statistics ---
2 packets transmitted, 0 received, 100% packet loss, time 1018ms
$ ping 192.0.2.2
PING 192.0.2.2 (192.0.2.2) 56(84) bytes of data.
^C
--- 192.0.2.2 ping statistics ---
3 packets transmitted, 0 received, 100% packet loss, time 2039ms
$ sudo ip addr add 192.0.2.1/24 dev lo
$ ip addr show dev lo
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group ...
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet 192.0.2.1/24 scope global lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
$ ping 192.0.2.1
PING 192.0.2.1 (192.0.2.1) 56(84) bytes of data.
64 bytes from 192.0.2.1: icmp_seq=1 ttl=64 time=0.131 ms
64 bytes from 192.0.2.1: icmp_seq=2 ttl=64 time=0.046 ms
64 bytes from 192.0.2.1: icmp_seq=3 ttl=64 time=0.048 ms
^C
--- 192.0.2.1 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2042ms
rtt min/avg/max/mdev = 0.046/0.075/0.131/0.039 ms
$ ping 192.0.2.2
PING 192.0.2.2 (192.0.2.2) 56(84) bytes of data.
64 bytes from 192.0.2.2: icmp_seq=1 ttl=64 time=0.131 ms
64 bytes from 192.0.2.2: icmp_seq=2 ttl=64 time=0.069 ms
64 bytes from 192.0.2.2: icmp_seq=3 ttl=64 time=0.049 ms
64 bytes from 192.0.2.2: icmp_seq=4 ttl=64 time=0.035 ms
^C
--- 192.0.2.2 ping statistics ---
4 packets transmitted, 4 received, 0% packet loss, time 3049ms
rtt min/avg/max/mdev = 0.035/0.071/0.131/0.036 ms
```
Test: integration_test.TestLoopbackAcceptAllInSubnet
PiperOrigin-RevId: 328188546
Diffstat (limited to 'pkg/tcpip/stack/nic.go')
| -rw-r--r-- | pkg/tcpip/stack/nic.go | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/pkg/tcpip/stack/nic.go b/pkg/tcpip/stack/nic.go index 728292782..aff29f9cc 100644 --- a/pkg/tcpip/stack/nic.go +++ b/pkg/tcpip/stack/nic.go @@ -666,8 +666,19 @@ func (n *NIC) getRefOrCreateTemp(protocol tcpip.NetworkProtocolNumber, address t } // A usable reference was not found, create a temporary one if requested by - // the caller or if the address is found in the NIC's subnets. + // the caller or if the address is found in the NIC's subnets and the NIC is + // a loopback interface. createTempEP := spoofingOrPromiscuous + if !createTempEP && n.isLoopback() { + for _, r := range n.mu.endpoints { + addr := r.addrWithPrefix() + subnet := addr.Subnet() + if subnet.Contains(address) { + createTempEP = true + break + } + } + } n.mu.RUnlock() if !createTempEP { |