Commit 0ab5539f authored by Jakub Sitnicki's avatar Jakub Sitnicki Committed by Alexei Starovoitov
Browse files

selftests/bpf: Tests for BPF_SK_LOOKUP attach point 



Add tests to test_progs that exercise:

 - attaching/detaching/querying programs to BPF_SK_LOOKUP hook,
 - redirecting socket lookup to a socket selected by BPF program,
 - failing a socket lookup on BPF program's request,
 - error scenarios for selecting a socket from BPF program,
 - accessing BPF program context,
 - attaching and running multiple BPF programs.

Run log:

  bash-5.0# ./test_progs -n 70
  #70/1 query lookup prog:OK
  #70/2 TCP IPv4 redir port:OK
  #70/3 TCP IPv4 redir addr:OK
  #70/4 TCP IPv4 redir with reuseport:OK
  #70/5 TCP IPv4 redir skip reuseport:OK
  #70/6 TCP IPv6 redir port:OK
  #70/7 TCP IPv6 redir addr:OK
  #70/8 TCP IPv4->IPv6 redir port:OK
  #70/9 TCP IPv6 redir with reuseport:OK
  #70/10 TCP IPv6 redir skip reuseport:OK
  #70/11 UDP IPv4 redir port:OK
  #70/12 UDP IPv4 redir addr:OK
  #70/13 UDP IPv4 redir with reuseport:OK
  #70/14 UDP IPv4 redir skip reuseport:OK
  #70/15 UDP IPv6 redir port:OK
  #70/16 UDP IPv6 redir addr:OK
  #70/17 UDP IPv4->IPv6 redir port:OK
  #70/18 UDP IPv6 redir and reuseport:OK
  #70/19 UDP IPv6 redir skip reuseport:OK
  #70/20 TCP IPv4 drop on lookup:OK
  #70/21 TCP IPv6 drop on lookup:OK
  #70/22 UDP IPv4 drop on lookup:OK
  #70/23 UDP IPv6 drop on lookup:OK
  #70/24 TCP IPv4 drop on reuseport:OK
  #70/25 TCP IPv6 drop on reuseport:OK
  #70/26 UDP IPv4 drop on reuseport:OK
  #70/27 TCP IPv6 drop on reuseport:OK
  #70/28 sk_assign returns EEXIST:OK
  #70/29 sk_assign honors F_REPLACE:OK
  #70/30 sk_assign accepts NULL socket:OK
  #70/31 access ctx->sk:OK
  #70/32 narrow access to ctx v4:OK
  #70/33 narrow access to ctx v6:OK
  #70/34 sk_assign rejects TCP established:OK
  #70/35 sk_assign rejects UDP connected:OK
  #70/36 multi prog - pass, pass:OK
  #70/37 multi prog - drop, drop:OK
  #70/38 multi prog - pass, drop:OK
  #70/39 multi prog - drop, pass:OK
  #70/40 multi prog - pass, redir:OK
  #70/41 multi prog - redir, pass:OK
  #70/42 multi prog - drop, redir:OK
  #70/43 multi prog - redir, drop:OK
  #70/44 multi prog - redir, redir:OK
  #70 sk_lookup:OK
  Summary: 1/44 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: default avatarJakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200717103536.397595-16-jakub@cloudflare.com
parent f7726cbe

tools/testing/selftests/bpf/network_helpers.c

+35 −23
Original line number Diff line number Diff line
@@ -73,29 +73,8 @@ int start_server(int family, int type, const char *addr_str, __u16 port, 
	socklen_t len;

	int fd;



	if (family == AF_INET) {

		struct sockaddr_in *sin = (void *)&addr;



		sin->sin_family = AF_INET;

		sin->sin_port = htons(port);

		if (addr_str &&

		    inet_pton(AF_INET, addr_str, &sin->sin_addr) != 1) {

			log_err("inet_pton(AF_INET, %s)", addr_str);

	if (make_sockaddr(family, addr_str, port, &addr, &len))

		return -1;

		}

		len = sizeof(*sin);

	} else {

		struct sockaddr_in6 *sin6 = (void *)&addr;



		sin6->sin6_family = AF_INET6;

		sin6->sin6_port = htons(port);

		if (addr_str &&

		    inet_pton(AF_INET6, addr_str, &sin6->sin6_addr) != 1) {

			log_err("inet_pton(AF_INET6, %s)", addr_str);

			return -1;

		}

		len = sizeof(*sin6);

	}



	fd = socket(family, type, 0);

	if (fd < 0) {
@@ -194,3 +173,36 @@ int connect_fd_to_fd(int client_fd, int server_fd, int timeout_ms) 


	return 0;

}



int make_sockaddr(int family, const char *addr_str, __u16 port,

		  struct sockaddr_storage *addr, socklen_t *len)

{

	if (family == AF_INET) {

		struct sockaddr_in *sin = (void *)addr;



		sin->sin_family = AF_INET;

		sin->sin_port = htons(port);

		if (addr_str &&

		    inet_pton(AF_INET, addr_str, &sin->sin_addr) != 1) {

			log_err("inet_pton(AF_INET, %s)", addr_str);

			return -1;

		}

		if (len)

			*len = sizeof(*sin);

		return 0;

	} else if (family == AF_INET6) {

		struct sockaddr_in6 *sin6 = (void *)addr;



		sin6->sin6_family = AF_INET6;

		sin6->sin6_port = htons(port);

		if (addr_str &&

		    inet_pton(AF_INET6, addr_str, &sin6->sin6_addr) != 1) {

			log_err("inet_pton(AF_INET6, %s)", addr_str);

			return -1;

		}

		if (len)

			*len = sizeof(*sin6);

		return 0;

	}

	return -1;

}

tools/testing/selftests/bpf/network_helpers.h

+2 −0
Original line number Diff line number Diff line
@@ -37,5 +37,7 @@ int start_server(int family, int type, const char *addr, __u16 port, 
		 int timeout_ms);

int connect_to_fd(int server_fd, int timeout_ms);

int connect_fd_to_fd(int client_fd, int server_fd, int timeout_ms);

int make_sockaddr(int family, const char *addr_str, __u16 port,

		  struct sockaddr_storage *addr, socklen_t *len);



#endif

tools/testing/selftests/bpf/prog_tests/sk_lookup.c

0 → 100644
+1282 −0

File added.

Preview size limit exceeded, changes collapsed.

tools/testing/selftests/bpf/progs/test_sk_lookup.c

0 → 100644
+641 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause

// Copyright (c) 2020 Cloudflare



#include <errno.h>

#include <stdbool.h>

#include <stddef.h>

#include <linux/bpf.h>

#include <linux/in.h>

#include <sys/socket.h>



#include <bpf/bpf_endian.h>

#include <bpf/bpf_helpers.h>



#define IP4(a, b, c, d)					\

	bpf_htonl((((__u32)(a) & 0xffU) << 24) |	\

		  (((__u32)(b) & 0xffU) << 16) |	\

		  (((__u32)(c) & 0xffU) <<  8) |	\

		  (((__u32)(d) & 0xffU) <<  0))

#define IP6(aaaa, bbbb, cccc, dddd)			\

	{ bpf_htonl(aaaa), bpf_htonl(bbbb), bpf_htonl(cccc), bpf_htonl(dddd) }



#define MAX_SOCKS 32



struct {

	__uint(type, BPF_MAP_TYPE_SOCKMAP);

	__uint(max_entries, MAX_SOCKS);

	__type(key, __u32);

	__type(value, __u64);

} redir_map SEC(".maps");



struct {

	__uint(type, BPF_MAP_TYPE_ARRAY);

	__uint(max_entries, 2);

	__type(key, int);

	__type(value, int);

} run_map SEC(".maps");



enum {

	PROG1 = 0,

	PROG2,

};



enum {

	SERVER_A = 0,

	SERVER_B,

};



/* Addressable key/value constants for convenience */

static const int KEY_PROG1 = PROG1;

static const int KEY_PROG2 = PROG2;

static const int PROG_DONE = 1;



static const __u32 KEY_SERVER_A = SERVER_A;

static const __u32 KEY_SERVER_B = SERVER_B;



static const __u16 DST_PORT = 7007; /* Host byte order */

static const __u32 DST_IP4 = IP4(127, 0, 0, 1);

static const __u32 DST_IP6[] = IP6(0xfd000000, 0x0, 0x0, 0x00000001);



SEC("sk_lookup/lookup_pass")

int lookup_pass(struct bpf_sk_lookup *ctx)

{

	return SK_PASS;

}



SEC("sk_lookup/lookup_drop")

int lookup_drop(struct bpf_sk_lookup *ctx)

{

	return SK_DROP;

}



SEC("sk_reuseport/reuse_pass")

int reuseport_pass(struct sk_reuseport_md *ctx)

{

	return SK_PASS;

}



SEC("sk_reuseport/reuse_drop")

int reuseport_drop(struct sk_reuseport_md *ctx)

{

	return SK_DROP;

}



/* Redirect packets destined for port DST_PORT to socket at redir_map[0]. */

SEC("sk_lookup/redir_port")

int redir_port(struct bpf_sk_lookup *ctx)

{

	struct bpf_sock *sk;

	int err;



	if (ctx->local_port != DST_PORT)

		return SK_PASS;



	sk = bpf_map_lookup_elem(&redir_map, &KEY_SERVER_A);

	if (!sk)

		return SK_PASS;



	err = bpf_sk_assign(ctx, sk, 0);

	bpf_sk_release(sk);

	return err ? SK_DROP : SK_PASS;

}



/* Redirect packets destined for DST_IP4 address to socket at redir_map[0]. */

SEC("sk_lookup/redir_ip4")

int redir_ip4(struct bpf_sk_lookup *ctx)

{

	struct bpf_sock *sk;

	int err;



	if (ctx->family != AF_INET)

		return SK_PASS;

	if (ctx->local_port != DST_PORT)

		return SK_PASS;

	if (ctx->local_ip4 != DST_IP4)

		return SK_PASS;



	sk = bpf_map_lookup_elem(&redir_map, &KEY_SERVER_A);

	if (!sk)

		return SK_PASS;



	err = bpf_sk_assign(ctx, sk, 0);

	bpf_sk_release(sk);

	return err ? SK_DROP : SK_PASS;

}



/* Redirect packets destined for DST_IP6 address to socket at redir_map[0]. */

SEC("sk_lookup/redir_ip6")

int redir_ip6(struct bpf_sk_lookup *ctx)

{

	struct bpf_sock *sk;

	int err;



	if (ctx->family != AF_INET6)

		return SK_PASS;

	if (ctx->local_port != DST_PORT)

		return SK_PASS;

	if (ctx->local_ip6[0] != DST_IP6[0] ||

	    ctx->local_ip6[1] != DST_IP6[1] ||

	    ctx->local_ip6[2] != DST_IP6[2] ||

	    ctx->local_ip6[3] != DST_IP6[3])

		return SK_PASS;



	sk = bpf_map_lookup_elem(&redir_map, &KEY_SERVER_A);

	if (!sk)

		return SK_PASS;



	err = bpf_sk_assign(ctx, sk, 0);

	bpf_sk_release(sk);

	return err ? SK_DROP : SK_PASS;

}



SEC("sk_lookup/select_sock_a")

int select_sock_a(struct bpf_sk_lookup *ctx)

{

	struct bpf_sock *sk;

	int err;



	sk = bpf_map_lookup_elem(&redir_map, &KEY_SERVER_A);

	if (!sk)

		return SK_PASS;



	err = bpf_sk_assign(ctx, sk, 0);

	bpf_sk_release(sk);

	return err ? SK_DROP : SK_PASS;

}



SEC("sk_lookup/select_sock_a_no_reuseport")

int select_sock_a_no_reuseport(struct bpf_sk_lookup *ctx)

{

	struct bpf_sock *sk;

	int err;



	sk = bpf_map_lookup_elem(&redir_map, &KEY_SERVER_A);

	if (!sk)

		return SK_DROP;



	err = bpf_sk_assign(ctx, sk, BPF_SK_LOOKUP_F_NO_REUSEPORT);

	bpf_sk_release(sk);

	return err ? SK_DROP : SK_PASS;

}



SEC("sk_reuseport/select_sock_b")

int select_sock_b(struct sk_reuseport_md *ctx)

{

	__u32 key = KEY_SERVER_B;

	int err;



	err = bpf_sk_select_reuseport(ctx, &redir_map, &key, 0);

	return err ? SK_DROP : SK_PASS;

}



/* Check that bpf_sk_assign() returns -EEXIST if socket already selected. */

SEC("sk_lookup/sk_assign_eexist")

int sk_assign_eexist(struct bpf_sk_lookup *ctx)

{

	struct bpf_sock *sk;

	int err, ret;



	ret = SK_DROP;

	sk = bpf_map_lookup_elem(&redir_map, &KEY_SERVER_B);

	if (!sk)

		goto out;

	err = bpf_sk_assign(ctx, sk, 0);

	if (err)

		goto out;

	bpf_sk_release(sk);



	sk = bpf_map_lookup_elem(&redir_map, &KEY_SERVER_A);

	if (!sk)

		goto out;

	err = bpf_sk_assign(ctx, sk, 0);

	if (err != -EEXIST) {

		bpf_printk("sk_assign returned %d, expected %d\n",

			   err, -EEXIST);

		goto out;

	}



	ret = SK_PASS; /* Success, redirect to KEY_SERVER_B */

out:

	if (sk)

		bpf_sk_release(sk);

	return ret;

}



/* Check that bpf_sk_assign(BPF_SK_LOOKUP_F_REPLACE) can override selection. */

SEC("sk_lookup/sk_assign_replace_flag")

int sk_assign_replace_flag(struct bpf_sk_lookup *ctx)

{

	struct bpf_sock *sk;

	int err, ret;



	ret = SK_DROP;

	sk = bpf_map_lookup_elem(&redir_map, &KEY_SERVER_A);

	if (!sk)

		goto out;

	err = bpf_sk_assign(ctx, sk, 0);

	if (err)

		goto out;

	bpf_sk_release(sk);



	sk = bpf_map_lookup_elem(&redir_map, &KEY_SERVER_B);

	if (!sk)

		goto out;

	err = bpf_sk_assign(ctx, sk, BPF_SK_LOOKUP_F_REPLACE);

	if (err) {

		bpf_printk("sk_assign returned %d, expected 0\n", err);

		goto out;

	}



	ret = SK_PASS; /* Success, redirect to KEY_SERVER_B */

out:

	if (sk)

		bpf_sk_release(sk);

	return ret;

}



/* Check that bpf_sk_assign(sk=NULL) is accepted. */

SEC("sk_lookup/sk_assign_null")

int sk_assign_null(struct bpf_sk_lookup *ctx)

{

	struct bpf_sock *sk = NULL;

	int err, ret;



	ret = SK_DROP;



	err = bpf_sk_assign(ctx, NULL, 0);

	if (err) {

		bpf_printk("sk_assign returned %d, expected 0\n", err);

		goto out;

	}



	sk = bpf_map_lookup_elem(&redir_map, &KEY_SERVER_B);

	if (!sk)

		goto out;

	err = bpf_sk_assign(ctx, sk, BPF_SK_LOOKUP_F_REPLACE);

	if (err) {

		bpf_printk("sk_assign returned %d, expected 0\n", err);

		goto out;

	}



	if (ctx->sk != sk)

		goto out;

	err = bpf_sk_assign(ctx, NULL, 0);

	if (err != -EEXIST)

		goto out;

	err = bpf_sk_assign(ctx, NULL, BPF_SK_LOOKUP_F_REPLACE);

	if (err)

		goto out;

	err = bpf_sk_assign(ctx, sk, BPF_SK_LOOKUP_F_REPLACE);

	if (err)

		goto out;



	ret = SK_PASS; /* Success, redirect to KEY_SERVER_B */

out:

	if (sk)

		bpf_sk_release(sk);

	return ret;

}



/* Check that selected sk is accessible through context. */

SEC("sk_lookup/access_ctx_sk")

int access_ctx_sk(struct bpf_sk_lookup *ctx)

{

	struct bpf_sock *sk1 = NULL, *sk2 = NULL;

	int err, ret;



	ret = SK_DROP;



	/* Try accessing unassigned (NULL) ctx->sk field */

	if (ctx->sk && ctx->sk->family != AF_INET)

		goto out;



	/* Assign a value to ctx->sk */

	sk1 = bpf_map_lookup_elem(&redir_map, &KEY_SERVER_A);

	if (!sk1)

		goto out;

	err = bpf_sk_assign(ctx, sk1, 0);

	if (err)

		goto out;

	if (ctx->sk != sk1)

		goto out;



	/* Access ctx->sk fields */

	if (ctx->sk->family != AF_INET ||

	    ctx->sk->type != SOCK_STREAM ||

	    ctx->sk->state != BPF_TCP_LISTEN)

		goto out;



	/* Reset selection */

	err = bpf_sk_assign(ctx, NULL, BPF_SK_LOOKUP_F_REPLACE);

	if (err)

		goto out;

	if (ctx->sk)

		goto out;



	/* Assign another socket */

	sk2 = bpf_map_lookup_elem(&redir_map, &KEY_SERVER_B);

	if (!sk2)

		goto out;

	err = bpf_sk_assign(ctx, sk2, BPF_SK_LOOKUP_F_REPLACE);

	if (err)

		goto out;

	if (ctx->sk != sk2)

		goto out;



	/* Access reassigned ctx->sk fields */

	if (ctx->sk->family != AF_INET ||

	    ctx->sk->type != SOCK_STREAM ||

	    ctx->sk->state != BPF_TCP_LISTEN)

		goto out;



	ret = SK_PASS; /* Success, redirect to KEY_SERVER_B */

out:

	if (sk1)

		bpf_sk_release(sk1);

	if (sk2)

		bpf_sk_release(sk2);

	return ret;

}



/* Check narrow loads from ctx fields that support them.

 *

 * Narrow loads of size >= target field size from a non-zero offset

 * are not covered because they give bogus results, that is the

 * verifier ignores the offset.

 */

SEC("sk_lookup/ctx_narrow_access")

int ctx_narrow_access(struct bpf_sk_lookup *ctx)

{

	struct bpf_sock *sk;

	int err, family;

	__u16 *half;

	__u8 *byte;

	bool v4;



	v4 = (ctx->family == AF_INET);



	/* Narrow loads from family field */

	byte = (__u8 *)&ctx->family;

	half = (__u16 *)&ctx->family;

	if (byte[0] != (v4 ? AF_INET : AF_INET6) ||

	    byte[1] != 0 || byte[2] != 0 || byte[3] != 0)

		return SK_DROP;

	if (half[0] != (v4 ? AF_INET : AF_INET6))

		return SK_DROP;



	byte = (__u8 *)&ctx->protocol;

	if (byte[0] != IPPROTO_TCP ||

	    byte[1] != 0 || byte[2] != 0 || byte[3] != 0)

		return SK_DROP;

	half = (__u16 *)&ctx->protocol;

	if (half[0] != IPPROTO_TCP)

		return SK_DROP;



	/* Narrow loads from remote_port field. Expect non-0 value. */

	byte = (__u8 *)&ctx->remote_port;

	if (byte[0] == 0 && byte[1] == 0 && byte[2] == 0 && byte[3] == 0)

		return SK_DROP;

	half = (__u16 *)&ctx->remote_port;

	if (half[0] == 0)

		return SK_DROP;



	/* Narrow loads from local_port field. Expect DST_PORT. */

	byte = (__u8 *)&ctx->local_port;

	if (byte[0] != ((DST_PORT >> 0) & 0xff) ||

	    byte[1] != ((DST_PORT >> 8) & 0xff) ||

	    byte[2] != 0 || byte[3] != 0)

		return SK_DROP;

	half = (__u16 *)&ctx->local_port;

	if (half[0] != DST_PORT)

		return SK_DROP;



	/* Narrow loads from IPv4 fields */

	if (v4) {

		/* Expect non-0.0.0.0 in remote_ip4 */

		byte = (__u8 *)&ctx->remote_ip4;

		if (byte[0] == 0 && byte[1] == 0 &&

		    byte[2] == 0 && byte[3] == 0)

			return SK_DROP;

		half = (__u16 *)&ctx->remote_ip4;

		if (half[0] == 0 && half[1] == 0)

			return SK_DROP;



		/* Expect DST_IP4 in local_ip4 */

		byte = (__u8 *)&ctx->local_ip4;

		if (byte[0] != ((DST_IP4 >>  0) & 0xff) ||

		    byte[1] != ((DST_IP4 >>  8) & 0xff) ||

		    byte[2] != ((DST_IP4 >> 16) & 0xff) ||

		    byte[3] != ((DST_IP4 >> 24) & 0xff))

			return SK_DROP;

		half = (__u16 *)&ctx->local_ip4;

		if (half[0] != ((DST_IP4 >>  0) & 0xffff) ||

		    half[1] != ((DST_IP4 >> 16) & 0xffff))

			return SK_DROP;

	} else {

		/* Expect 0.0.0.0 IPs when family != AF_INET */

		byte = (__u8 *)&ctx->remote_ip4;

		if (byte[0] != 0 || byte[1] != 0 &&

		    byte[2] != 0 || byte[3] != 0)

			return SK_DROP;

		half = (__u16 *)&ctx->remote_ip4;

		if (half[0] != 0 || half[1] != 0)

			return SK_DROP;



		byte = (__u8 *)&ctx->local_ip4;

		if (byte[0] != 0 || byte[1] != 0 &&

		    byte[2] != 0 || byte[3] != 0)

			return SK_DROP;

		half = (__u16 *)&ctx->local_ip4;

		if (half[0] != 0 || half[1] != 0)

			return SK_DROP;

	}



	/* Narrow loads from IPv6 fields */

	if (!v4) {

		/* Expenct non-:: IP in remote_ip6 */

		byte = (__u8 *)&ctx->remote_ip6;

		if (byte[0] == 0 && byte[1] == 0 &&

		    byte[2] == 0 && byte[3] == 0 &&

		    byte[4] == 0 && byte[5] == 0 &&

		    byte[6] == 0 && byte[7] == 0 &&

		    byte[8] == 0 && byte[9] == 0 &&

		    byte[10] == 0 && byte[11] == 0 &&

		    byte[12] == 0 && byte[13] == 0 &&

		    byte[14] == 0 && byte[15] == 0)

			return SK_DROP;

		half = (__u16 *)&ctx->remote_ip6;

		if (half[0] == 0 && half[1] == 0 &&

		    half[2] == 0 && half[3] == 0 &&

		    half[4] == 0 && half[5] == 0 &&

		    half[6] == 0 && half[7] == 0)

			return SK_DROP;



		/* Expect DST_IP6 in local_ip6 */

		byte = (__u8 *)&ctx->local_ip6;

		if (byte[0] != ((DST_IP6[0] >>  0) & 0xff) ||

		    byte[1] != ((DST_IP6[0] >>  8) & 0xff) ||

		    byte[2] != ((DST_IP6[0] >> 16) & 0xff) ||

		    byte[3] != ((DST_IP6[0] >> 24) & 0xff) ||

		    byte[4] != ((DST_IP6[1] >>  0) & 0xff) ||

		    byte[5] != ((DST_IP6[1] >>  8) & 0xff) ||

		    byte[6] != ((DST_IP6[1] >> 16) & 0xff) ||

		    byte[7] != ((DST_IP6[1] >> 24) & 0xff) ||

		    byte[8] != ((DST_IP6[2] >>  0) & 0xff) ||

		    byte[9] != ((DST_IP6[2] >>  8) & 0xff) ||

		    byte[10] != ((DST_IP6[2] >> 16) & 0xff) ||

		    byte[11] != ((DST_IP6[2] >> 24) & 0xff) ||

		    byte[12] != ((DST_IP6[3] >>  0) & 0xff) ||

		    byte[13] != ((DST_IP6[3] >>  8) & 0xff) ||

		    byte[14] != ((DST_IP6[3] >> 16) & 0xff) ||

		    byte[15] != ((DST_IP6[3] >> 24) & 0xff))

			return SK_DROP;

		half = (__u16 *)&ctx->local_ip6;

		if (half[0] != ((DST_IP6[0] >>  0) & 0xffff) ||

		    half[1] != ((DST_IP6[0] >> 16) & 0xffff) ||

		    half[2] != ((DST_IP6[1] >>  0) & 0xffff) ||

		    half[3] != ((DST_IP6[1] >> 16) & 0xffff) ||

		    half[4] != ((DST_IP6[2] >>  0) & 0xffff) ||

		    half[5] != ((DST_IP6[2] >> 16) & 0xffff) ||

		    half[6] != ((DST_IP6[3] >>  0) & 0xffff) ||

		    half[7] != ((DST_IP6[3] >> 16) & 0xffff))

			return SK_DROP;

	} else {

		/* Expect :: IPs when family != AF_INET6 */

		byte = (__u8 *)&ctx->remote_ip6;

		if (byte[0] != 0 || byte[1] != 0 ||

		    byte[2] != 0 || byte[3] != 0 ||

		    byte[4] != 0 || byte[5] != 0 ||

		    byte[6] != 0 || byte[7] != 0 ||

		    byte[8] != 0 || byte[9] != 0 ||

		    byte[10] != 0 || byte[11] != 0 ||

		    byte[12] != 0 || byte[13] != 0 ||

		    byte[14] != 0 || byte[15] != 0)

			return SK_DROP;

		half = (__u16 *)&ctx->remote_ip6;

		if (half[0] != 0 || half[1] != 0 ||

		    half[2] != 0 || half[3] != 0 ||

		    half[4] != 0 || half[5] != 0 ||

		    half[6] != 0 || half[7] != 0)

			return SK_DROP;



		byte = (__u8 *)&ctx->local_ip6;

		if (byte[0] != 0 || byte[1] != 0 ||

		    byte[2] != 0 || byte[3] != 0 ||

		    byte[4] != 0 || byte[5] != 0 ||

		    byte[6] != 0 || byte[7] != 0 ||

		    byte[8] != 0 || byte[9] != 0 ||

		    byte[10] != 0 || byte[11] != 0 ||

		    byte[12] != 0 || byte[13] != 0 ||

		    byte[14] != 0 || byte[15] != 0)

			return SK_DROP;

		half = (__u16 *)&ctx->local_ip6;

		if (half[0] != 0 || half[1] != 0 ||

		    half[2] != 0 || half[3] != 0 ||

		    half[4] != 0 || half[5] != 0 ||

		    half[6] != 0 || half[7] != 0)

			return SK_DROP;

	}



	/* Success, redirect to KEY_SERVER_B */

	sk = bpf_map_lookup_elem(&redir_map, &KEY_SERVER_B);

	if (sk) {

		bpf_sk_assign(ctx, sk, 0);

		bpf_sk_release(sk);

	}

	return SK_PASS;

}



/* Check that sk_assign rejects SERVER_A socket with -ESOCKNOSUPPORT */

SEC("sk_lookup/sk_assign_esocknosupport")

int sk_assign_esocknosupport(struct bpf_sk_lookup *ctx)

{

	struct bpf_sock *sk;

	int err, ret;



	ret = SK_DROP;

	sk = bpf_map_lookup_elem(&redir_map, &KEY_SERVER_A);

	if (!sk)

		goto out;



	err = bpf_sk_assign(ctx, sk, 0);

	if (err != -ESOCKTNOSUPPORT) {

		bpf_printk("sk_assign returned %d, expected %d\n",

			   err, -ESOCKTNOSUPPORT);

		goto out;

	}



	ret = SK_PASS; /* Success, pass to regular lookup */

out:

	if (sk)

		bpf_sk_release(sk);

	return ret;

}



SEC("sk_lookup/multi_prog_pass1")

int multi_prog_pass1(struct bpf_sk_lookup *ctx)

{

	bpf_map_update_elem(&run_map, &KEY_PROG1, &PROG_DONE, BPF_ANY);

	return SK_PASS;

}



SEC("sk_lookup/multi_prog_pass2")

int multi_prog_pass2(struct bpf_sk_lookup *ctx)

{

	bpf_map_update_elem(&run_map, &KEY_PROG2, &PROG_DONE, BPF_ANY);

	return SK_PASS;

}



SEC("sk_lookup/multi_prog_drop1")

int multi_prog_drop1(struct bpf_sk_lookup *ctx)

{

	bpf_map_update_elem(&run_map, &KEY_PROG1, &PROG_DONE, BPF_ANY);

	return SK_DROP;

}



SEC("sk_lookup/multi_prog_drop2")

int multi_prog_drop2(struct bpf_sk_lookup *ctx)

{

	bpf_map_update_elem(&run_map, &KEY_PROG2, &PROG_DONE, BPF_ANY);

	return SK_DROP;

}



static __always_inline int select_server_a(struct bpf_sk_lookup *ctx)

{

	struct bpf_sock *sk;

	int err;



	sk = bpf_map_lookup_elem(&redir_map, &KEY_SERVER_A);

	if (!sk)

		return SK_DROP;



	err = bpf_sk_assign(ctx, sk, 0);

	bpf_sk_release(sk);

	if (err)

		return SK_DROP;



	return SK_PASS;

}



SEC("sk_lookup/multi_prog_redir1")

int multi_prog_redir1(struct bpf_sk_lookup *ctx)

{

	int ret;



	ret = select_server_a(ctx);

	bpf_map_update_elem(&run_map, &KEY_PROG1, &PROG_DONE, BPF_ANY);

	return SK_PASS;

}



SEC("sk_lookup/multi_prog_redir2")

int multi_prog_redir2(struct bpf_sk_lookup *ctx)

{

	int ret;



	ret = select_server_a(ctx);

	bpf_map_update_elem(&run_map, &KEY_PROG2, &PROG_DONE, BPF_ANY);

	return SK_PASS;

}



char _license[] SEC("license") = "Dual BSD/GPL";

__u32 _version SEC("version") = 1;

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