Commit f649f992 authored by Martin KaFai Lau's avatar Martin KaFai Lau Committed by Alexei Starovoitov
Browse files

selftest/bpf: Add test for bpf_getsockopt() 



This patch removes the __bpf_getsockopt() which directly
reads the sk by using PTR_TO_BTF_ID.  Instead, the test now directly
uses the kernel bpf helper bpf_getsockopt() which supports all
the required optname now.

TCP_SAVE[D]_SYN and TCP_MAXSEG are not tested in a loop for all
the hooks and sock_ops's cb.  TCP_SAVE[D]_SYN only works
in passive connection.  TCP_MAXSEG only works when
it is setsockopt before the connection is established and
the getsockopt return value can only be tested after
the connection is established.

Signed-off-by: default avatarMartin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20220902002937.2896904-1-kafai@fb.com


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 38566ec0

tools/testing/selftests/bpf/progs/bpf_tracing_net.h

+1 −0
Original line number Diff line number Diff line
@@ -38,6 +38,7 @@ 
#define TCP_USER_TIMEOUT	18

#define TCP_NOTSENT_LOWAT	25

#define TCP_SAVE_SYN		27

#define TCP_SAVED_SYN		28

#define TCP_CA_NAME_MAX		16

#define TCP_NAGLE_OFF		1

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

+42 −106
Original line number Diff line number Diff line
@@ -52,7 +52,6 @@ static const struct sockopt_test sol_socket_tests[] = { 


static const struct sockopt_test sol_tcp_tests[] = {

	{ .opt = TCP_NODELAY, .flip = 1, },

	{ .opt = TCP_MAXSEG, .new = 1314, .expected = 1314, },

	{ .opt = TCP_KEEPIDLE, .new = 123, .expected = 123, .restore = 321, },

	{ .opt = TCP_KEEPINTVL, .new = 123, .expected = 123, .restore = 321, },

	{ .opt = TCP_KEEPCNT, .new = 123, .expected = 123, .restore = 124, },
@@ -62,7 +61,6 @@ static const struct sockopt_test sol_tcp_tests[] = { 
	{ .opt = TCP_THIN_LINEAR_TIMEOUTS, .flip = 1, },

	{ .opt = TCP_USER_TIMEOUT, .new = 123400, .expected = 123400, },

	{ .opt = TCP_NOTSENT_LOWAT, .new = 1314, .expected = 1314, },

	{ .opt = TCP_SAVE_SYN, .new = 1, .expected = 1, },

	{ .opt = 0, },

};
@@ -82,102 +80,6 @@ struct loop_ctx { 
	struct sock *sk;

};



static int __bpf_getsockopt(void *ctx, struct sock *sk,

			    int level, int opt, int *optval,

			    int optlen)

{

	if (level == SOL_SOCKET) {

		switch (opt) {

		case SO_REUSEADDR:

			*optval = !!BPF_CORE_READ_BITFIELD(sk, sk_reuse);

			break;

		case SO_KEEPALIVE:

			*optval = !!(sk->sk_flags & (1UL << 3));

			break;

		case SO_RCVLOWAT:

			*optval = sk->sk_rcvlowat;

			break;

		case SO_MAX_PACING_RATE:

			*optval = sk->sk_max_pacing_rate;

			break;

		default:

			return bpf_getsockopt(ctx, level, opt, optval, optlen);

		}

		return 0;

	}



	if (level == IPPROTO_TCP) {

		struct tcp_sock *tp = bpf_skc_to_tcp_sock(sk);



		if (!tp)

			return -1;



		switch (opt) {

		case TCP_NODELAY:

			*optval = !!(BPF_CORE_READ_BITFIELD(tp, nonagle) & TCP_NAGLE_OFF);

			break;

		case TCP_MAXSEG:

			*optval = tp->rx_opt.user_mss;

			break;

		case TCP_KEEPIDLE:

			*optval = tp->keepalive_time / CONFIG_HZ;

			break;

		case TCP_SYNCNT:

			*optval = tp->inet_conn.icsk_syn_retries;

			break;

		case TCP_KEEPINTVL:

			*optval = tp->keepalive_intvl / CONFIG_HZ;

			break;

		case TCP_KEEPCNT:

			*optval = tp->keepalive_probes;

			break;

		case TCP_WINDOW_CLAMP:

			*optval = tp->window_clamp;

			break;

		case TCP_THIN_LINEAR_TIMEOUTS:

			*optval = !!BPF_CORE_READ_BITFIELD(tp, thin_lto);

			break;

		case TCP_USER_TIMEOUT:

			*optval = tp->inet_conn.icsk_user_timeout;

			break;

		case TCP_NOTSENT_LOWAT:

			*optval = tp->notsent_lowat;

			break;

		case TCP_SAVE_SYN:

			*optval = BPF_CORE_READ_BITFIELD(tp, save_syn);

			break;

		default:

			return bpf_getsockopt(ctx, level, opt, optval, optlen);

		}

		return 0;

	}



	if (level == IPPROTO_IPV6) {

		switch (opt) {

		case IPV6_AUTOFLOWLABEL: {

			__u16 proto = sk->sk_protocol;

			struct inet_sock *inet_sk;



			if (proto == IPPROTO_TCP)

				inet_sk = (struct inet_sock *)bpf_skc_to_tcp_sock(sk);

			else

				inet_sk = (struct inet_sock *)bpf_skc_to_udp6_sock(sk);



			if (!inet_sk)

				return -1;



			*optval = !!inet_sk->pinet6->autoflowlabel;

			break;

		}

		default:

			return bpf_getsockopt(ctx, level, opt, optval, optlen);

		}

		return 0;

	}



	return bpf_getsockopt(ctx, level, opt, optval, optlen);

}



static int bpf_test_sockopt_flip(void *ctx, struct sock *sk,

				 const struct sockopt_test *t,

				 int level)
@@ -186,7 +88,7 @@ static int bpf_test_sockopt_flip(void *ctx, struct sock *sk, 


	opt = t->opt;



	if (__bpf_getsockopt(ctx, sk, level, opt, &old, sizeof(old)))

	if (bpf_getsockopt(ctx, level, opt, &old, sizeof(old)))

		return 1;

	/* kernel initialized txrehash to 255 */

	if (level == SOL_SOCKET && opt == SO_TXREHASH && old != 0 && old != 1)
@@ -195,7 +97,7 @@ static int bpf_test_sockopt_flip(void *ctx, struct sock *sk, 
	new = !old;

	if (bpf_setsockopt(ctx, level, opt, &new, sizeof(new)))

		return 1;

	if (__bpf_getsockopt(ctx, sk, level, opt, &tmp, sizeof(tmp)) ||

	if (bpf_getsockopt(ctx, level, opt, &tmp, sizeof(tmp)) ||

	    tmp != new)

		return 1;
@@ -218,13 +120,13 @@ static int bpf_test_sockopt_int(void *ctx, struct sock *sk, 
	else

		expected = t->expected;



	if (__bpf_getsockopt(ctx, sk, level, opt, &old, sizeof(old)) ||

	if (bpf_getsockopt(ctx, level, opt, &old, sizeof(old)) ||

	    old == new)

		return 1;



	if (bpf_setsockopt(ctx, level, opt, &new, sizeof(new)))

		return 1;

	if (__bpf_getsockopt(ctx, sk, level, opt, &tmp, sizeof(tmp)) ||

	if (bpf_getsockopt(ctx, level, opt, &tmp, sizeof(tmp)) ||

	    tmp != expected)

		return 1;
@@ -410,6 +312,34 @@ static int binddev_test(void *ctx) 
	return 0;

}



static int test_tcp_maxseg(void *ctx, struct sock *sk)

{

	int val = 1314, tmp;



	if (sk->sk_state != TCP_ESTABLISHED)

		return bpf_setsockopt(ctx, IPPROTO_TCP, TCP_MAXSEG,

				      &val, sizeof(val));



	if (bpf_getsockopt(ctx, IPPROTO_TCP, TCP_MAXSEG, &tmp, sizeof(tmp)) ||

	    tmp > val)

		return -1;



	return 0;

}



static int test_tcp_saved_syn(void *ctx, struct sock *sk)

{

	__u8 saved_syn[20];

	int one = 1;



	if (sk->sk_state == TCP_LISTEN)

		return bpf_setsockopt(ctx, IPPROTO_TCP, TCP_SAVE_SYN,

				      &one, sizeof(one));



	return bpf_getsockopt(ctx, IPPROTO_TCP, TCP_SAVED_SYN,

			      saved_syn, sizeof(saved_syn));

}



SEC("lsm_cgroup/socket_post_create")

int BPF_PROG(socket_post_create, struct socket *sock, int family,

	     int type, int protocol, int kern)
@@ -440,16 +370,22 @@ int skops_sockopt(struct bpf_sock_ops *skops) 


	switch (skops->op) {

	case BPF_SOCK_OPS_TCP_LISTEN_CB:

		nr_listen += !bpf_test_sockopt(skops, sk);

		nr_listen += !(bpf_test_sockopt(skops, sk) ||

			       test_tcp_maxseg(skops, sk) ||

			       test_tcp_saved_syn(skops, sk));

		break;

	case BPF_SOCK_OPS_TCP_CONNECT_CB:

		nr_connect += !bpf_test_sockopt(skops, sk);

		nr_connect += !(bpf_test_sockopt(skops, sk) ||

				test_tcp_maxseg(skops, sk));

		break;

	case BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB:

		nr_active += !bpf_test_sockopt(skops, sk);

		nr_active += !(bpf_test_sockopt(skops, sk) ||

			       test_tcp_maxseg(skops, sk));

		break;

	case BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB:

		nr_passive += !bpf_test_sockopt(skops, sk);

		nr_passive += !(bpf_test_sockopt(skops, sk) ||

				test_tcp_maxseg(skops, sk) ||

				test_tcp_saved_syn(skops, sk));

		break;

	}