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

#include <linux/net_tstamp.h>
#include <sys/time.h>
#include <linux/errqueue.h>
#include "test_progs.h"
#include "network_helpers.h"
#include "net_timestamping.skel.h"

#define CG_NAME "/net-timestamping-test"
#define NSEC_PER_SEC    1000000000LL

static const char addr4_str[] = "127.0.0.1";
static const char addr6_str[] = "::1";
static struct net_timestamping *skel;
static const int cfg_payload_len = 30;
static struct timespec usr_ts;
static u64 delay_tolerance_nsec = 10000000000; /* 10 seconds */
int SK_TS_SCHED;
int SK_TS_TXSW;
int SK_TS_ACK;

static int64_t timespec_to_ns64(struct timespec *ts)
{
	return ts->tv_sec * NSEC_PER_SEC + ts->tv_nsec;
}

static void validate_key(int tskey, int tstype)
{
	static int expected_tskey = -1;

	if (tstype == SCM_TSTAMP_SCHED)
		expected_tskey = cfg_payload_len - 1;

	ASSERT_EQ(expected_tskey, tskey, "tskey mismatch");

	expected_tskey = tskey;
}

static void validate_timestamp(struct timespec *cur, struct timespec *prev)
{
	int64_t cur_ns, prev_ns;

	cur_ns = timespec_to_ns64(cur);
	prev_ns = timespec_to_ns64(prev);

	ASSERT_LT(cur_ns - prev_ns, delay_tolerance_nsec, "latency");
}

static void test_socket_timestamp(struct scm_timestamping *tss, int tstype,
				  int tskey)
{
	static struct timespec prev_ts;

	validate_key(tskey, tstype);

	switch (tstype) {
	case SCM_TSTAMP_SCHED:
		validate_timestamp(&tss->ts[0], &usr_ts);
		SK_TS_SCHED += 1;
		break;
	case SCM_TSTAMP_SND:
		validate_timestamp(&tss->ts[0], &prev_ts);
		SK_TS_TXSW += 1;
		break;
	case SCM_TSTAMP_ACK:
		validate_timestamp(&tss->ts[0], &prev_ts);
		SK_TS_ACK += 1;
		break;
	}

	prev_ts = tss->ts[0];
}

static void test_recv_errmsg_cmsg(struct msghdr *msg)
{
	struct sock_extended_err *serr = NULL;
	struct scm_timestamping *tss = NULL;
	struct cmsghdr *cm;

	for (cm = CMSG_FIRSTHDR(msg);
	     cm && cm->cmsg_len;
	     cm = CMSG_NXTHDR(msg, cm)) {
		if (cm->cmsg_level == SOL_SOCKET &&
		    cm->cmsg_type == SCM_TIMESTAMPING) {
			tss = (void *)CMSG_DATA(cm);
		} else if ((cm->cmsg_level == SOL_IP &&
			    cm->cmsg_type == IP_RECVERR) ||
			   (cm->cmsg_level == SOL_IPV6 &&
			    cm->cmsg_type == IPV6_RECVERR) ||
			   (cm->cmsg_level == SOL_PACKET &&
			    cm->cmsg_type == PACKET_TX_TIMESTAMP)) {
			serr = (void *)CMSG_DATA(cm);
			ASSERT_EQ(serr->ee_origin, SO_EE_ORIGIN_TIMESTAMPING,
				  "cmsg type");
		}

		if (serr && tss)
			test_socket_timestamp(tss, serr->ee_info,
					      serr->ee_data);
	}
}

static bool socket_recv_errmsg(int fd)
{
	static char ctrl[1024 /* overprovision*/];
	char data[cfg_payload_len];
	static struct msghdr msg;
	struct iovec entry;
	int n = 0;

	memset(&msg, 0, sizeof(msg));
	memset(&entry, 0, sizeof(entry));
	memset(ctrl, 0, sizeof(ctrl));

	entry.iov_base = data;
	entry.iov_len = cfg_payload_len;
	msg.msg_iov = &entry;
	msg.msg_iovlen = 1;
	msg.msg_name = NULL;
	msg.msg_namelen = 0;
	msg.msg_control = ctrl;
	msg.msg_controllen = sizeof(ctrl);

	n = recvmsg(fd, &msg, MSG_ERRQUEUE);
	if (n == -1)
		ASSERT_EQ(errno, EAGAIN, "recvmsg MSG_ERRQUEUE");

	if (n >= 0)
		test_recv_errmsg_cmsg(&msg);

	return n == -1;
}

static void test_socket_timestamping(int fd)
{
	while (!socket_recv_errmsg(fd));

	ASSERT_EQ(SK_TS_SCHED, 1, "SCM_TSTAMP_SCHED");
	ASSERT_EQ(SK_TS_TXSW, 1, "SCM_TSTAMP_SND");
	ASSERT_EQ(SK_TS_ACK, 1, "SCM_TSTAMP_ACK");

	SK_TS_SCHED = 0;
	SK_TS_TXSW = 0;
	SK_TS_ACK = 0;
}

static void test_tcp(int family, bool enable_socket_timestamping)
{
	struct net_timestamping__bss *bss;
	char buf[cfg_payload_len];
	int sfd = -1, cfd = -1;
	unsigned int sock_opt;
	struct netns_obj *ns;
	int cg_fd;
	int ret;

	cg_fd = test__join_cgroup(CG_NAME);
	if (!ASSERT_OK_FD(cg_fd, "join cgroup"))
		return;

	ns = netns_new("net_timestamping_ns", true);
	if (!ASSERT_OK_PTR(ns, "create ns"))
		goto out;

	skel = net_timestamping__open_and_load();
	if (!ASSERT_OK_PTR(skel, "open and load skel"))
		goto out;

	if (!ASSERT_OK(net_timestamping__attach(skel), "attach skel"))
		goto out;

	skel->links.skops_sockopt =
		bpf_program__attach_cgroup(skel->progs.skops_sockopt, cg_fd);
	if (!ASSERT_OK_PTR(skel->links.skops_sockopt, "attach cgroup"))
		goto out;

	bss = skel->bss;
	memset(bss, 0, sizeof(*bss));

	skel->bss->monitored_pid = getpid();

	sfd = start_server(family, SOCK_STREAM,
			   family == AF_INET6 ? addr6_str : addr4_str, 0, 0);
	if (!ASSERT_OK_FD(sfd, "start_server"))
		goto out;

	cfd = connect_to_fd(sfd, 0);
	if (!ASSERT_OK_FD(cfd, "connect_to_fd_server"))
		goto out;

	if (enable_socket_timestamping) {
		sock_opt = SOF_TIMESTAMPING_SOFTWARE |
			   SOF_TIMESTAMPING_OPT_ID |
			   SOF_TIMESTAMPING_TX_SCHED |
			   SOF_TIMESTAMPING_TX_SOFTWARE |
			   SOF_TIMESTAMPING_TX_ACK;
		ret = setsockopt(cfd, SOL_SOCKET, SO_TIMESTAMPING,
				 (char *) &sock_opt, sizeof(sock_opt));
		if (!ASSERT_OK(ret, "setsockopt SO_TIMESTAMPING"))
			goto out;

		ret = clock_gettime(CLOCK_REALTIME, &usr_ts);
		if (!ASSERT_OK(ret, "get user time"))
			goto out;
	}

	ret = write(cfd, buf, sizeof(buf));
	if (!ASSERT_EQ(ret, sizeof(buf), "send to server"))
		goto out;

	if (enable_socket_timestamping)
		test_socket_timestamping(cfd);

	ASSERT_EQ(bss->nr_active, 1, "nr_active");
	ASSERT_EQ(bss->nr_snd, 2, "nr_snd");
	ASSERT_EQ(bss->nr_sched, 1, "nr_sched");
	ASSERT_EQ(bss->nr_txsw, 1, "nr_txsw");
	ASSERT_EQ(bss->nr_ack, 1, "nr_ack");

out:
	if (sfd >= 0)
		close(sfd);
	if (cfd >= 0)
		close(cfd);
	net_timestamping__destroy(skel);
	netns_free(ns);
	close(cg_fd);
}

void test_net_timestamping(void)
{
	if (test__start_subtest("INET4: bpf timestamping"))
		test_tcp(AF_INET, false);
	if (test__start_subtest("INET4: bpf and socket timestamping"))
		test_tcp(AF_INET, true);
	if (test__start_subtest("INET6: bpf timestamping"))
		test_tcp(AF_INET6, false);
	if (test__start_subtest("INET6: bpf and socket timestamping"))
		test_tcp(AF_INET6, true);
}