Add a tun_vnet_udptnl_proto fixture writing single 4in4 Geneve GSO frames to a tap device with UDP tunnel offloads enabled:
- outer_proto_ok: an outer IPv4 header, with or without an 802.1Q tag, is accepted. - outer_proto_bad: an outer ethertype that does not match the declared tunnel type (IPv6 on an IPv4 tunnel, or NSH, with or without a VLAN tag) is rejected with EINVAL. Without the previous virtio_net patch, outer_proto_bad fails because the kernel accepts the frames. Signed-off-by: Eric Dumazet <[email protected]> --- tools/testing/selftests/net/tun.c | 130 ++++++++++++++++++++++++++++++ 1 file changed, 130 insertions(+) diff --git a/tools/testing/selftests/net/tun.c b/tools/testing/selftests/net/tun.c index 34de2580e32e..47a24b9c477b 100644 --- a/tools/testing/selftests/net/tun.c +++ b/tools/testing/selftests/net/tun.c @@ -683,6 +683,136 @@ TEST_F(tun_vnet_gso, vlan_tcpv4_gso_no_csum_64k) ASSERT_EQ(ret, len); } +#ifndef ETH_P_NSH +#define ETH_P_NSH 0x894F +#endif + +FIXTURE(tun_vnet_udptnl_proto) +{ + char ifname[IFNAMSIZ]; + uint8_t *pkt; + int fd; +}; + +FIXTURE_SETUP(tun_vnet_udptnl_proto) +{ + int flags = IFF_TAP | IFF_NO_PI | IFF_VNET_HDR; + int features = TUN_F_CSUM | TUN_F_UDP_TUNNEL_GSO | + TUN_F_UDP_TUNNEL_GSO_CSUM | TUN_F_USO4 | TUN_F_USO6; + + self->fd = -1; + if (unshare(CLONE_NEWNET)) + SKIP(return, "Cannot create network namespace: %s", + strerror(errno)); + + self->pkt = calloc(1, MAX_VNET_TUNNEL_PACKET_SZ); + ASSERT_NE(self->pkt, NULL); + + memset(self->ifname, 0, sizeof(self->ifname)); + self->fd = tun_open(self->ifname, flags, TUN_VNET_TNL_SIZE, features, + param_hwaddr_outer_src); + ASSERT_GE(self->fd, 0); +} + +FIXTURE_TEARDOWN(tun_vnet_udptnl_proto) +{ + if (self->fd >= 0) + close(self->fd); + free(self->pkt); +} + +/* Build a 4in4 Geneve GSO frame whose outer ethertype is @l3proto, + * optionally behind an 802.1Q tag. + */ +static int build_udptnl_frame(uint8_t *buf, bool vlan, uint16_t l3proto, + int payload_len) +{ + struct virtio_net_hdr_v1_hash_tunnel *vh = (void *)buf; + int vlan_len = vlan ? 4 : 0; + int hlen = ETH_HLEN + vlan_len + UDP_TUNNEL_GENEVE_4IN4_HDRLEN; + uint8_t *outer_udph, *cur = buf; + int pktlen; + + cur += build_virtio_net_hdr_v1_hash_tunnel(cur, true, hlen, 1400, + AF_INET, AF_INET); + vh->outer_th_offset += vlan_len; + vh->inner_nh_offset += vlan_len; + vh->hash_hdr.hdr.csum_start += vlan_len; + + if (vlan) { + uint16_t vlan_tag[2] = { htons(100), htons(l3proto) }; + + cur += build_eth(cur, ETH_P_8021Q, param_hwaddr_outer_dst, + param_hwaddr_outer_src); + memcpy(cur, vlan_tag, sizeof(vlan_tag)); + cur += sizeof(vlan_tag); + } else { + cur += build_eth(cur, l3proto, param_hwaddr_outer_dst, + param_hwaddr_outer_src); + } + + pktlen = UDP_TUNNEL_GENEVE_4IN4_HDRLEN - sizeof(struct iphdr) + + payload_len; + cur += build_ipv4_header(cur, IPPROTO_UDP, pktlen, + ¶m_ipaddr4_outer_dst, + ¶m_ipaddr4_outer_src); + + outer_udph = cur; + cur += build_udp_header(cur, UDP_SRC_PORT, VN_PORT, + pktlen - sizeof(struct udphdr)); + cur += build_geneve_header(cur, VN_ID); + cur += build_eth(cur, ETH_P_IP, param_hwaddr_inner_dst, + param_hwaddr_inner_src); + cur += build_ipv4_header(cur, IPPROTO_UDP, + sizeof(struct udphdr) + payload_len, + ¶m_ipaddr4_inner_dst, + ¶m_ipaddr4_inner_src); + cur += build_udp_packet(cur, UDP_DST_PORT, UDP_SRC_PORT, payload_len, + AF_INET, false); + build_udp_packet_csum(outer_udph, AF_INET, false); + + return cur - buf; +} + +TEST_F(tun_vnet_udptnl_proto, outer_proto_ok) +{ + uint8_t *pkt = self->pkt; + int len, ret; + + len = build_udptnl_frame(pkt, false, ETH_P_IP, 2800); + ret = write(self->fd, pkt, len); + ASSERT_EQ(ret, len); + + /* The outer IPv4 header can follow a VLAN tag. */ + len = build_udptnl_frame(pkt, true, ETH_P_IP, 2800); + ret = write(self->fd, pkt, len); + ASSERT_EQ(ret, len); +} + +TEST_F(tun_vnet_udptnl_proto, outer_proto_bad) +{ + uint8_t *pkt = self->pkt; + int len, ret; + + /* Outer ethertype does not match the declared IPv4 tunnel. */ + len = build_udptnl_frame(pkt, false, ETH_P_IPV6, 2800); + ret = write(self->fd, pkt, len); + ASSERT_EQ(ret, -1); + ASSERT_EQ(errno, EINVAL); + + /* Outer header is not IP at all. */ + len = build_udptnl_frame(pkt, false, ETH_P_NSH, 2800); + ret = write(self->fd, pkt, len); + ASSERT_EQ(ret, -1); + ASSERT_EQ(errno, EINVAL); + + /* Same, behind a VLAN tag. */ + len = build_udptnl_frame(pkt, true, ETH_P_NSH, 2800); + ret = write(self->fd, pkt, len); + ASSERT_EQ(ret, -1); + ASSERT_EQ(errno, EINVAL); +} + FIXTURE(tun_vnet_udptnl) { char ifname[IFNAMSIZ]; -- 2.53.0
