samples/bpf: add comprehensive ipip, ipip6, ip6ip6 test

the test creates 3 namespaces with veth connected via bridge.
First two namespaces simulate two different hosts with the same
IPv4 and IPv6 addresses configured on the tunnel interface and they
communicate with outside world via standard tunnels.
Third namespace creates collect_md tunnel that is driven by BPF
program which selects different remote host (either first or
second namespace) based on tcp dest port number while tcp dst
ip is the same.
This scenario is rough approximation of load balancer use case.
The tests check both traditional tunnel configuration and collect_md mode.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 132 insertions, 0 deletions

diff --git a/samples/bpf/tcbpf2_kern.c b/samples/bpf/tcbpf2_kern.c
index c1917d968fb4..3303bb85593b 100644
--- a/samples/bpf/tcbpf2_kern.c
+++ b/samples/bpf/tcbpf2_kern.c
@@ -9,12 +9,15 @@
 #include <uapi/linux/if_ether.h>
 #include <uapi/linux/if_packet.h>
 #include <uapi/linux/ip.h>
+#include <uapi/linux/ipv6.h>
 #include <uapi/linux/in.h>
 #include <uapi/linux/tcp.h>
 #include <uapi/linux/filter.h>
 #include <uapi/linux/pkt_cls.h>
+#include <net/ipv6.h>
 #include "bpf_helpers.h"
 
+#define _htonl __builtin_bswap32
 #define ERROR(ret) do {\
 		char fmt[] = "ERROR line:%d ret:%d\n";\
 		bpf_trace_printk(fmt, sizeof(fmt), __LINE__, ret); \
@@ -246,4 +249,133 @@ int _ipip_get_tunnel(struct __sk_buff *skb)
 	return TC_ACT_OK;
 }
 
+SEC("ipip6_set_tunnel")
+int _ipip6_set_tunnel(struct __sk_buff *skb)
+{
+	struct bpf_tunnel_key key = {};
+	void *data = (void *)(long)skb->data;
+	struct iphdr *iph = data;
+	struct tcphdr *tcp = data + sizeof(*iph);
+	void *data_end = (void *)(long)skb->data_end;
+	int ret;
+
+	/* single length check */
+	if (data + sizeof(*iph) + sizeof(*tcp) > data_end) {
+		ERROR(1);
+		return TC_ACT_SHOT;
+	}
+
+	key.remote_ipv6[0] = _htonl(0x2401db00);
+	key.tunnel_ttl = 64;
+
+	if (iph->protocol == IPPROTO_ICMP) {
+		key.remote_ipv6[3] = _htonl(1);
+	} else {
+		if (iph->protocol != IPPROTO_TCP || iph->ihl != 5) {
+			ERROR(iph->protocol);
+			return TC_ACT_SHOT;
+		}
+
+		if (tcp->dest == htons(5200)) {
+			key.remote_ipv6[3] = _htonl(1);
+		} else if (tcp->dest == htons(5201)) {
+			key.remote_ipv6[3] = _htonl(2);
+		} else {
+			ERROR(tcp->dest);
+			return TC_ACT_SHOT;
+		}
+	}
+
+	ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key), BPF_F_TUNINFO_IPV6);
+	if (ret < 0) {
+		ERROR(ret);
+		return TC_ACT_SHOT;
+	}
+
+	return TC_ACT_OK;
+}
+
+SEC("ipip6_get_tunnel")
+int _ipip6_get_tunnel(struct __sk_buff *skb)
+{
+	int ret;
+	struct bpf_tunnel_key key;
+	char fmt[] = "remote ip6 %x::%x\n";
+
+	ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), BPF_F_TUNINFO_IPV6);
+	if (ret < 0) {
+		ERROR(ret);
+		return TC_ACT_SHOT;
+	}
+
+	bpf_trace_printk(fmt, sizeof(fmt), _htonl(key.remote_ipv6[0]),
+			 _htonl(key.remote_ipv6[3]));
+	return TC_ACT_OK;
+}
+
+SEC("ip6ip6_set_tunnel")
+int _ip6ip6_set_tunnel(struct __sk_buff *skb)
+{
+	struct bpf_tunnel_key key = {};
+	void *data = (void *)(long)skb->data;
+	struct ipv6hdr *iph = data;
+	struct tcphdr *tcp = data + sizeof(*iph);
+	void *data_end = (void *)(long)skb->data_end;
+	int ret;
+
+	/* single length check */
+	if (data + sizeof(*iph) + sizeof(*tcp) > data_end) {
+		ERROR(1);
+		return TC_ACT_SHOT;
+	}
+
+	key.remote_ipv6[0] = _htonl(0x2401db00);
+	key.tunnel_ttl = 64;
+
+	if (iph->nexthdr == NEXTHDR_ICMP) {
+		key.remote_ipv6[3] = _htonl(1);
+	} else {
+		if (iph->nexthdr != NEXTHDR_TCP) {
+			ERROR(iph->nexthdr);
+			return TC_ACT_SHOT;
+		}
+
+		if (tcp->dest == htons(5200)) {
+			key.remote_ipv6[3] = _htonl(1);
+		} else if (tcp->dest == htons(5201)) {
+			key.remote_ipv6[3] = _htonl(2);
+		} else {
+			ERROR(tcp->dest);
+			return TC_ACT_SHOT;
+		}
+	}
+
+	ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key), BPF_F_TUNINFO_IPV6);
+	if (ret < 0) {
+		ERROR(ret);
+		return TC_ACT_SHOT;
+	}
+
+	return TC_ACT_OK;
+}
+
+SEC("ip6ip6_get_tunnel")
+int _ip6ip6_get_tunnel(struct __sk_buff *skb)
+{
+	int ret;
+	struct bpf_tunnel_key key;
+	char fmt[] = "remote ip6 %x::%x\n";
+
+	ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), BPF_F_TUNINFO_IPV6);
+	if (ret < 0) {
+		ERROR(ret);
+		return TC_ACT_SHOT;
+	}
+
+	bpf_trace_printk(fmt, sizeof(fmt), _htonl(key.remote_ipv6[0]),
+			 _htonl(key.remote_ipv6[3]));
+	return TC_ACT_OK;
+}
+
+
 char _license[] SEC("license") = "GPL";