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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /tools/testing/selftests/bpf/progs/test_tc_tunnel.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/testing/selftests/bpf/progs/test_tc_tunnel.c')
-rw-r--r--tools/testing/selftests/bpf/progs/test_tc_tunnel.c620
1 files changed, 620 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/test_tc_tunnel.c b/tools/testing/selftests/bpf/progs/test_tc_tunnel.c
new file mode 100644
index 000000000..a0e7762b1
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/test_tc_tunnel.c
@@ -0,0 +1,620 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/* In-place tunneling */
+
+#include <stdbool.h>
+#include <string.h>
+
+#include <linux/stddef.h>
+#include <linux/bpf.h>
+#include <linux/if_ether.h>
+#include <linux/in.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <linux/mpls.h>
+#include <linux/tcp.h>
+#include <linux/udp.h>
+#include <linux/pkt_cls.h>
+#include <linux/types.h>
+
+#include <bpf/bpf_endian.h>
+#include <bpf/bpf_helpers.h>
+
+static const int cfg_port = 8000;
+
+static const int cfg_udp_src = 20000;
+
+#define L2_PAD_SZ (sizeof(struct vxlanhdr) + ETH_HLEN)
+
+#define UDP_PORT 5555
+#define MPLS_OVER_UDP_PORT 6635
+#define ETH_OVER_UDP_PORT 7777
+#define VXLAN_UDP_PORT 8472
+
+#define EXTPROTO_VXLAN 0x1
+
+#define VXLAN_N_VID (1u << 24)
+#define VXLAN_VNI_MASK bpf_htonl((VXLAN_N_VID - 1) << 8)
+#define VXLAN_FLAGS 0x8
+#define VXLAN_VNI 1
+
+/* MPLS label 1000 with S bit (last label) set and ttl of 255. */
+static const __u32 mpls_label = __bpf_constant_htonl(1000 << 12 |
+ MPLS_LS_S_MASK | 0xff);
+
+struct vxlanhdr {
+ __be32 vx_flags;
+ __be32 vx_vni;
+} __attribute__((packed));
+
+struct gre_hdr {
+ __be16 flags;
+ __be16 protocol;
+} __attribute__((packed));
+
+union l4hdr {
+ struct udphdr udp;
+ struct gre_hdr gre;
+};
+
+struct v4hdr {
+ struct iphdr ip;
+ union l4hdr l4hdr;
+ __u8 pad[L2_PAD_SZ]; /* space for L2 header / vxlan header ... */
+} __attribute__((packed));
+
+struct v6hdr {
+ struct ipv6hdr ip;
+ union l4hdr l4hdr;
+ __u8 pad[L2_PAD_SZ]; /* space for L2 header / vxlan header ... */
+} __attribute__((packed));
+
+static __always_inline void set_ipv4_csum(struct iphdr *iph)
+{
+ __u16 *iph16 = (__u16 *)iph;
+ __u32 csum;
+ int i;
+
+ iph->check = 0;
+
+#pragma clang loop unroll(full)
+ for (i = 0, csum = 0; i < sizeof(*iph) >> 1; i++)
+ csum += *iph16++;
+
+ iph->check = ~((csum & 0xffff) + (csum >> 16));
+}
+
+static __always_inline int __encap_ipv4(struct __sk_buff *skb, __u8 encap_proto,
+ __u16 l2_proto, __u16 ext_proto)
+{
+ __u16 udp_dst = UDP_PORT;
+ struct iphdr iph_inner;
+ struct v4hdr h_outer;
+ struct tcphdr tcph;
+ int olen, l2_len;
+ __u8 *l2_hdr = NULL;
+ int tcp_off;
+ __u64 flags;
+
+ /* Most tests encapsulate a packet into a tunnel with the same
+ * network protocol, and derive the outer header fields from
+ * the inner header.
+ *
+ * The 6in4 case tests different inner and outer protocols. As
+ * the inner is ipv6, but the outer expects an ipv4 header as
+ * input, manually build a struct iphdr based on the ipv6hdr.
+ */
+ if (encap_proto == IPPROTO_IPV6) {
+ const __u32 saddr = (192 << 24) | (168 << 16) | (1 << 8) | 1;
+ const __u32 daddr = (192 << 24) | (168 << 16) | (1 << 8) | 2;
+ struct ipv6hdr iph6_inner;
+
+ /* Read the IPv6 header */
+ if (bpf_skb_load_bytes(skb, ETH_HLEN, &iph6_inner,
+ sizeof(iph6_inner)) < 0)
+ return TC_ACT_OK;
+
+ /* Derive the IPv4 header fields from the IPv6 header */
+ memset(&iph_inner, 0, sizeof(iph_inner));
+ iph_inner.version = 4;
+ iph_inner.ihl = 5;
+ iph_inner.tot_len = bpf_htons(sizeof(iph6_inner) +
+ bpf_ntohs(iph6_inner.payload_len));
+ iph_inner.ttl = iph6_inner.hop_limit - 1;
+ iph_inner.protocol = iph6_inner.nexthdr;
+ iph_inner.saddr = __bpf_constant_htonl(saddr);
+ iph_inner.daddr = __bpf_constant_htonl(daddr);
+
+ tcp_off = sizeof(iph6_inner);
+ } else {
+ if (bpf_skb_load_bytes(skb, ETH_HLEN, &iph_inner,
+ sizeof(iph_inner)) < 0)
+ return TC_ACT_OK;
+
+ tcp_off = sizeof(iph_inner);
+ }
+
+ /* filter only packets we want */
+ if (iph_inner.ihl != 5 || iph_inner.protocol != IPPROTO_TCP)
+ return TC_ACT_OK;
+
+ if (bpf_skb_load_bytes(skb, ETH_HLEN + tcp_off,
+ &tcph, sizeof(tcph)) < 0)
+ return TC_ACT_OK;
+
+ if (tcph.dest != __bpf_constant_htons(cfg_port))
+ return TC_ACT_OK;
+
+ olen = sizeof(h_outer.ip);
+ l2_len = 0;
+
+ flags = BPF_F_ADJ_ROOM_FIXED_GSO | BPF_F_ADJ_ROOM_ENCAP_L3_IPV4;
+
+ switch (l2_proto) {
+ case ETH_P_MPLS_UC:
+ l2_len = sizeof(mpls_label);
+ udp_dst = MPLS_OVER_UDP_PORT;
+ break;
+ case ETH_P_TEB:
+ l2_len = ETH_HLEN;
+ if (ext_proto & EXTPROTO_VXLAN) {
+ udp_dst = VXLAN_UDP_PORT;
+ l2_len += sizeof(struct vxlanhdr);
+ } else
+ udp_dst = ETH_OVER_UDP_PORT;
+ break;
+ }
+ flags |= BPF_F_ADJ_ROOM_ENCAP_L2(l2_len);
+
+ switch (encap_proto) {
+ case IPPROTO_GRE:
+ flags |= BPF_F_ADJ_ROOM_ENCAP_L4_GRE;
+ olen += sizeof(h_outer.l4hdr.gre);
+ h_outer.l4hdr.gre.protocol = bpf_htons(l2_proto);
+ h_outer.l4hdr.gre.flags = 0;
+ break;
+ case IPPROTO_UDP:
+ flags |= BPF_F_ADJ_ROOM_ENCAP_L4_UDP;
+ olen += sizeof(h_outer.l4hdr.udp);
+ h_outer.l4hdr.udp.source = __bpf_constant_htons(cfg_udp_src);
+ h_outer.l4hdr.udp.dest = bpf_htons(udp_dst);
+ h_outer.l4hdr.udp.check = 0;
+ h_outer.l4hdr.udp.len = bpf_htons(bpf_ntohs(iph_inner.tot_len) +
+ sizeof(h_outer.l4hdr.udp) +
+ l2_len);
+ break;
+ case IPPROTO_IPIP:
+ case IPPROTO_IPV6:
+ break;
+ default:
+ return TC_ACT_OK;
+ }
+
+ /* add L2 encap (if specified) */
+ l2_hdr = (__u8 *)&h_outer + olen;
+ switch (l2_proto) {
+ case ETH_P_MPLS_UC:
+ *(__u32 *)l2_hdr = mpls_label;
+ break;
+ case ETH_P_TEB:
+ flags |= BPF_F_ADJ_ROOM_ENCAP_L2_ETH;
+
+ if (ext_proto & EXTPROTO_VXLAN) {
+ struct vxlanhdr *vxlan_hdr = (struct vxlanhdr *)l2_hdr;
+
+ vxlan_hdr->vx_flags = VXLAN_FLAGS;
+ vxlan_hdr->vx_vni = bpf_htonl((VXLAN_VNI & VXLAN_VNI_MASK) << 8);
+
+ l2_hdr += sizeof(struct vxlanhdr);
+ }
+
+ if (bpf_skb_load_bytes(skb, 0, l2_hdr, ETH_HLEN))
+ return TC_ACT_SHOT;
+
+ break;
+ }
+ olen += l2_len;
+
+ /* add room between mac and network header */
+ if (bpf_skb_adjust_room(skb, olen, BPF_ADJ_ROOM_MAC, flags))
+ return TC_ACT_SHOT;
+
+ /* prepare new outer network header */
+ h_outer.ip = iph_inner;
+ h_outer.ip.tot_len = bpf_htons(olen +
+ bpf_ntohs(h_outer.ip.tot_len));
+ h_outer.ip.protocol = encap_proto;
+
+ set_ipv4_csum((void *)&h_outer.ip);
+
+ /* store new outer network header */
+ if (bpf_skb_store_bytes(skb, ETH_HLEN, &h_outer, olen,
+ BPF_F_INVALIDATE_HASH) < 0)
+ return TC_ACT_SHOT;
+
+ /* if changing outer proto type, update eth->h_proto */
+ if (encap_proto == IPPROTO_IPV6) {
+ struct ethhdr eth;
+
+ if (bpf_skb_load_bytes(skb, 0, &eth, sizeof(eth)) < 0)
+ return TC_ACT_SHOT;
+ eth.h_proto = bpf_htons(ETH_P_IP);
+ if (bpf_skb_store_bytes(skb, 0, &eth, sizeof(eth), 0) < 0)
+ return TC_ACT_SHOT;
+ }
+
+ return TC_ACT_OK;
+}
+
+static __always_inline int encap_ipv4(struct __sk_buff *skb, __u8 encap_proto,
+ __u16 l2_proto)
+{
+ return __encap_ipv4(skb, encap_proto, l2_proto, 0);
+}
+
+static __always_inline int __encap_ipv6(struct __sk_buff *skb, __u8 encap_proto,
+ __u16 l2_proto, __u16 ext_proto)
+{
+ __u16 udp_dst = UDP_PORT;
+ struct ipv6hdr iph_inner;
+ struct v6hdr h_outer;
+ struct tcphdr tcph;
+ int olen, l2_len;
+ __u8 *l2_hdr = NULL;
+ __u16 tot_len;
+ __u64 flags;
+
+ if (bpf_skb_load_bytes(skb, ETH_HLEN, &iph_inner,
+ sizeof(iph_inner)) < 0)
+ return TC_ACT_OK;
+
+ /* filter only packets we want */
+ if (bpf_skb_load_bytes(skb, ETH_HLEN + sizeof(iph_inner),
+ &tcph, sizeof(tcph)) < 0)
+ return TC_ACT_OK;
+
+ if (tcph.dest != __bpf_constant_htons(cfg_port))
+ return TC_ACT_OK;
+
+ olen = sizeof(h_outer.ip);
+ l2_len = 0;
+
+ flags = BPF_F_ADJ_ROOM_FIXED_GSO | BPF_F_ADJ_ROOM_ENCAP_L3_IPV6;
+
+ switch (l2_proto) {
+ case ETH_P_MPLS_UC:
+ l2_len = sizeof(mpls_label);
+ udp_dst = MPLS_OVER_UDP_PORT;
+ break;
+ case ETH_P_TEB:
+ l2_len = ETH_HLEN;
+ if (ext_proto & EXTPROTO_VXLAN) {
+ udp_dst = VXLAN_UDP_PORT;
+ l2_len += sizeof(struct vxlanhdr);
+ } else
+ udp_dst = ETH_OVER_UDP_PORT;
+ break;
+ }
+ flags |= BPF_F_ADJ_ROOM_ENCAP_L2(l2_len);
+
+ switch (encap_proto) {
+ case IPPROTO_GRE:
+ flags |= BPF_F_ADJ_ROOM_ENCAP_L4_GRE;
+ olen += sizeof(h_outer.l4hdr.gre);
+ h_outer.l4hdr.gre.protocol = bpf_htons(l2_proto);
+ h_outer.l4hdr.gre.flags = 0;
+ break;
+ case IPPROTO_UDP:
+ flags |= BPF_F_ADJ_ROOM_ENCAP_L4_UDP;
+ olen += sizeof(h_outer.l4hdr.udp);
+ h_outer.l4hdr.udp.source = __bpf_constant_htons(cfg_udp_src);
+ h_outer.l4hdr.udp.dest = bpf_htons(udp_dst);
+ tot_len = bpf_ntohs(iph_inner.payload_len) + sizeof(iph_inner) +
+ sizeof(h_outer.l4hdr.udp) + l2_len;
+ h_outer.l4hdr.udp.check = 0;
+ h_outer.l4hdr.udp.len = bpf_htons(tot_len);
+ break;
+ case IPPROTO_IPV6:
+ break;
+ default:
+ return TC_ACT_OK;
+ }
+
+ /* add L2 encap (if specified) */
+ l2_hdr = (__u8 *)&h_outer + olen;
+ switch (l2_proto) {
+ case ETH_P_MPLS_UC:
+ *(__u32 *)l2_hdr = mpls_label;
+ break;
+ case ETH_P_TEB:
+ flags |= BPF_F_ADJ_ROOM_ENCAP_L2_ETH;
+
+ if (ext_proto & EXTPROTO_VXLAN) {
+ struct vxlanhdr *vxlan_hdr = (struct vxlanhdr *)l2_hdr;
+
+ vxlan_hdr->vx_flags = VXLAN_FLAGS;
+ vxlan_hdr->vx_vni = bpf_htonl((VXLAN_VNI & VXLAN_VNI_MASK) << 8);
+
+ l2_hdr += sizeof(struct vxlanhdr);
+ }
+
+ if (bpf_skb_load_bytes(skb, 0, l2_hdr, ETH_HLEN))
+ return TC_ACT_SHOT;
+ break;
+ }
+ olen += l2_len;
+
+ /* add room between mac and network header */
+ if (bpf_skb_adjust_room(skb, olen, BPF_ADJ_ROOM_MAC, flags))
+ return TC_ACT_SHOT;
+
+ /* prepare new outer network header */
+ h_outer.ip = iph_inner;
+ h_outer.ip.payload_len = bpf_htons(olen +
+ bpf_ntohs(h_outer.ip.payload_len));
+
+ h_outer.ip.nexthdr = encap_proto;
+
+ /* store new outer network header */
+ if (bpf_skb_store_bytes(skb, ETH_HLEN, &h_outer, olen,
+ BPF_F_INVALIDATE_HASH) < 0)
+ return TC_ACT_SHOT;
+
+ return TC_ACT_OK;
+}
+
+static __always_inline int encap_ipv6(struct __sk_buff *skb, __u8 encap_proto,
+ __u16 l2_proto)
+{
+ return __encap_ipv6(skb, encap_proto, l2_proto, 0);
+}
+
+SEC("encap_ipip_none")
+int __encap_ipip_none(struct __sk_buff *skb)
+{
+ if (skb->protocol == __bpf_constant_htons(ETH_P_IP))
+ return encap_ipv4(skb, IPPROTO_IPIP, ETH_P_IP);
+ else
+ return TC_ACT_OK;
+}
+
+SEC("encap_gre_none")
+int __encap_gre_none(struct __sk_buff *skb)
+{
+ if (skb->protocol == __bpf_constant_htons(ETH_P_IP))
+ return encap_ipv4(skb, IPPROTO_GRE, ETH_P_IP);
+ else
+ return TC_ACT_OK;
+}
+
+SEC("encap_gre_mpls")
+int __encap_gre_mpls(struct __sk_buff *skb)
+{
+ if (skb->protocol == __bpf_constant_htons(ETH_P_IP))
+ return encap_ipv4(skb, IPPROTO_GRE, ETH_P_MPLS_UC);
+ else
+ return TC_ACT_OK;
+}
+
+SEC("encap_gre_eth")
+int __encap_gre_eth(struct __sk_buff *skb)
+{
+ if (skb->protocol == __bpf_constant_htons(ETH_P_IP))
+ return encap_ipv4(skb, IPPROTO_GRE, ETH_P_TEB);
+ else
+ return TC_ACT_OK;
+}
+
+SEC("encap_udp_none")
+int __encap_udp_none(struct __sk_buff *skb)
+{
+ if (skb->protocol == __bpf_constant_htons(ETH_P_IP))
+ return encap_ipv4(skb, IPPROTO_UDP, ETH_P_IP);
+ else
+ return TC_ACT_OK;
+}
+
+SEC("encap_udp_mpls")
+int __encap_udp_mpls(struct __sk_buff *skb)
+{
+ if (skb->protocol == __bpf_constant_htons(ETH_P_IP))
+ return encap_ipv4(skb, IPPROTO_UDP, ETH_P_MPLS_UC);
+ else
+ return TC_ACT_OK;
+}
+
+SEC("encap_udp_eth")
+int __encap_udp_eth(struct __sk_buff *skb)
+{
+ if (skb->protocol == __bpf_constant_htons(ETH_P_IP))
+ return encap_ipv4(skb, IPPROTO_UDP, ETH_P_TEB);
+ else
+ return TC_ACT_OK;
+}
+
+SEC("encap_vxlan_eth")
+int __encap_vxlan_eth(struct __sk_buff *skb)
+{
+ if (skb->protocol == __bpf_constant_htons(ETH_P_IP))
+ return __encap_ipv4(skb, IPPROTO_UDP,
+ ETH_P_TEB,
+ EXTPROTO_VXLAN);
+ else
+ return TC_ACT_OK;
+}
+
+SEC("encap_sit_none")
+int __encap_sit_none(struct __sk_buff *skb)
+{
+ if (skb->protocol == __bpf_constant_htons(ETH_P_IPV6))
+ return encap_ipv4(skb, IPPROTO_IPV6, ETH_P_IP);
+ else
+ return TC_ACT_OK;
+}
+
+SEC("encap_ip6tnl_none")
+int __encap_ip6tnl_none(struct __sk_buff *skb)
+{
+ if (skb->protocol == __bpf_constant_htons(ETH_P_IPV6))
+ return encap_ipv6(skb, IPPROTO_IPV6, ETH_P_IPV6);
+ else
+ return TC_ACT_OK;
+}
+
+SEC("encap_ip6gre_none")
+int __encap_ip6gre_none(struct __sk_buff *skb)
+{
+ if (skb->protocol == __bpf_constant_htons(ETH_P_IPV6))
+ return encap_ipv6(skb, IPPROTO_GRE, ETH_P_IPV6);
+ else
+ return TC_ACT_OK;
+}
+
+SEC("encap_ip6gre_mpls")
+int __encap_ip6gre_mpls(struct __sk_buff *skb)
+{
+ if (skb->protocol == __bpf_constant_htons(ETH_P_IPV6))
+ return encap_ipv6(skb, IPPROTO_GRE, ETH_P_MPLS_UC);
+ else
+ return TC_ACT_OK;
+}
+
+SEC("encap_ip6gre_eth")
+int __encap_ip6gre_eth(struct __sk_buff *skb)
+{
+ if (skb->protocol == __bpf_constant_htons(ETH_P_IPV6))
+ return encap_ipv6(skb, IPPROTO_GRE, ETH_P_TEB);
+ else
+ return TC_ACT_OK;
+}
+
+SEC("encap_ip6udp_none")
+int __encap_ip6udp_none(struct __sk_buff *skb)
+{
+ if (skb->protocol == __bpf_constant_htons(ETH_P_IPV6))
+ return encap_ipv6(skb, IPPROTO_UDP, ETH_P_IPV6);
+ else
+ return TC_ACT_OK;
+}
+
+SEC("encap_ip6udp_mpls")
+int __encap_ip6udp_mpls(struct __sk_buff *skb)
+{
+ if (skb->protocol == __bpf_constant_htons(ETH_P_IPV6))
+ return encap_ipv6(skb, IPPROTO_UDP, ETH_P_MPLS_UC);
+ else
+ return TC_ACT_OK;
+}
+
+SEC("encap_ip6udp_eth")
+int __encap_ip6udp_eth(struct __sk_buff *skb)
+{
+ if (skb->protocol == __bpf_constant_htons(ETH_P_IPV6))
+ return encap_ipv6(skb, IPPROTO_UDP, ETH_P_TEB);
+ else
+ return TC_ACT_OK;
+}
+
+SEC("encap_ip6vxlan_eth")
+int __encap_ip6vxlan_eth(struct __sk_buff *skb)
+{
+ if (skb->protocol == __bpf_constant_htons(ETH_P_IPV6))
+ return __encap_ipv6(skb, IPPROTO_UDP,
+ ETH_P_TEB,
+ EXTPROTO_VXLAN);
+ else
+ return TC_ACT_OK;
+}
+
+static int decap_internal(struct __sk_buff *skb, int off, int len, char proto)
+{
+ struct gre_hdr greh;
+ struct udphdr udph;
+ int olen = len;
+
+ switch (proto) {
+ case IPPROTO_IPIP:
+ case IPPROTO_IPV6:
+ break;
+ case IPPROTO_GRE:
+ olen += sizeof(struct gre_hdr);
+ if (bpf_skb_load_bytes(skb, off + len, &greh, sizeof(greh)) < 0)
+ return TC_ACT_OK;
+ switch (bpf_ntohs(greh.protocol)) {
+ case ETH_P_MPLS_UC:
+ olen += sizeof(mpls_label);
+ break;
+ case ETH_P_TEB:
+ olen += ETH_HLEN;
+ break;
+ }
+ break;
+ case IPPROTO_UDP:
+ olen += sizeof(struct udphdr);
+ if (bpf_skb_load_bytes(skb, off + len, &udph, sizeof(udph)) < 0)
+ return TC_ACT_OK;
+ switch (bpf_ntohs(udph.dest)) {
+ case MPLS_OVER_UDP_PORT:
+ olen += sizeof(mpls_label);
+ break;
+ case ETH_OVER_UDP_PORT:
+ olen += ETH_HLEN;
+ break;
+ case VXLAN_UDP_PORT:
+ olen += ETH_HLEN + sizeof(struct vxlanhdr);
+ break;
+ }
+ break;
+ default:
+ return TC_ACT_OK;
+ }
+
+ if (bpf_skb_adjust_room(skb, -olen, BPF_ADJ_ROOM_MAC,
+ BPF_F_ADJ_ROOM_FIXED_GSO))
+ return TC_ACT_SHOT;
+
+ return TC_ACT_OK;
+}
+
+static int decap_ipv4(struct __sk_buff *skb)
+{
+ struct iphdr iph_outer;
+
+ if (bpf_skb_load_bytes(skb, ETH_HLEN, &iph_outer,
+ sizeof(iph_outer)) < 0)
+ return TC_ACT_OK;
+
+ if (iph_outer.ihl != 5)
+ return TC_ACT_OK;
+
+ return decap_internal(skb, ETH_HLEN, sizeof(iph_outer),
+ iph_outer.protocol);
+}
+
+static int decap_ipv6(struct __sk_buff *skb)
+{
+ struct ipv6hdr iph_outer;
+
+ if (bpf_skb_load_bytes(skb, ETH_HLEN, &iph_outer,
+ sizeof(iph_outer)) < 0)
+ return TC_ACT_OK;
+
+ return decap_internal(skb, ETH_HLEN, sizeof(iph_outer),
+ iph_outer.nexthdr);
+}
+
+SEC("decap")
+int decap_f(struct __sk_buff *skb)
+{
+ switch (skb->protocol) {
+ case __bpf_constant_htons(ETH_P_IP):
+ return decap_ipv4(skb);
+ case __bpf_constant_htons(ETH_P_IPV6):
+ return decap_ipv6(skb);
+ default:
+ /* does not match, ignore */
+ return TC_ACT_OK;
+ }
+}
+
+char __license[] SEC("license") = "GPL";