selftests/net: Add TCP-AO library

Provide functions to create selftests dedicated to TCP-AO.
They can run in parallel, as they use temporary net namespaces.
They can be very specific to the feature being tested.
This will allow to create a lot of TCP-AO tests, without complicating
one binary with many --options and to create scenarios, that are
hard to put in bash script that uses one binary.

Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 254 insertions, 0 deletions

diff --git a/tools/testing/selftests/net/tcp_ao/lib/repair.c b/tools/testing/selftests/net/tcp_ao/lib/repair.c
new file mode 100644
index 000000000000..9893b3ba69f5
--- /dev/null
+++ b/tools/testing/selftests/net/tcp_ao/lib/repair.c
@@ -0,0 +1,254 @@
+// SPDX-License-Identifier: GPL-2.0
+/* This is over-simplified TCP_REPAIR for TCP_ESTABLISHED sockets
+ * It tests that TCP-AO enabled connection can be restored.
+ * For the proper socket repair see:
+ * https://github.com/checkpoint-restore/criu/blob/criu-dev/soccr/soccr.h
+ */
+#include <fcntl.h>
+#include <linux/sockios.h>
+#include <sys/ioctl.h>
+#include "aolib.h"
+
+#ifndef TCPOPT_MAXSEG
+# define TCPOPT_MAXSEG		2
+#endif
+#ifndef TCPOPT_WINDOW
+# define TCPOPT_WINDOW		3
+#endif
+#ifndef TCPOPT_SACK_PERMITTED
+# define TCPOPT_SACK_PERMITTED	4
+#endif
+#ifndef TCPOPT_TIMESTAMP
+# define TCPOPT_TIMESTAMP	8
+#endif
+
+enum {
+	TCP_ESTABLISHED = 1,
+	TCP_SYN_SENT,
+	TCP_SYN_RECV,
+	TCP_FIN_WAIT1,
+	TCP_FIN_WAIT2,
+	TCP_TIME_WAIT,
+	TCP_CLOSE,
+	TCP_CLOSE_WAIT,
+	TCP_LAST_ACK,
+	TCP_LISTEN,
+	TCP_CLOSING,	/* Now a valid state */
+	TCP_NEW_SYN_RECV,
+
+	TCP_MAX_STATES	/* Leave at the end! */
+};
+
+static void test_sock_checkpoint_queue(int sk, int queue, int qlen,
+				       struct tcp_sock_queue *q)
+{
+	socklen_t len;
+	int ret;
+
+	if (setsockopt(sk, SOL_TCP, TCP_REPAIR_QUEUE, &queue, sizeof(queue)))
+		test_error("setsockopt(TCP_REPAIR_QUEUE)");
+
+	len = sizeof(q->seq);
+	ret = getsockopt(sk, SOL_TCP, TCP_QUEUE_SEQ, &q->seq, &len);
+	if (ret || len != sizeof(q->seq))
+		test_error("getsockopt(TCP_QUEUE_SEQ): %d", (int)len);
+
+	if (!qlen) {
+		q->buf = NULL;
+		return;
+	}
+
+	q->buf = malloc(qlen);
+	if (q->buf == NULL)
+		test_error("malloc()");
+	ret = recv(sk, q->buf, qlen, MSG_PEEK | MSG_DONTWAIT);
+	if (ret != qlen)
+		test_error("recv(%d): %d", qlen, ret);
+}
+
+void __test_sock_checkpoint(int sk, struct tcp_sock_state *state,
+			    void *addr, size_t addr_size)
+{
+	socklen_t len = sizeof(state->info);
+	int ret;
+
+	memset(state, 0, sizeof(*state));
+
+	ret = getsockopt(sk, SOL_TCP, TCP_INFO, &state->info, &len);
+	if (ret || len != sizeof(state->info))
+		test_error("getsockopt(TCP_INFO): %d", (int)len);
+
+	len = addr_size;
+	if (getsockname(sk, addr, &len) || len != addr_size)
+		test_error("getsockname(): %d", (int)len);
+
+	len = sizeof(state->trw);
+	ret = getsockopt(sk, SOL_TCP, TCP_REPAIR_WINDOW, &state->trw, &len);
+	if (ret || len != sizeof(state->trw))
+		test_error("getsockopt(TCP_REPAIR_WINDOW): %d", (int)len);
+
+	if (ioctl(sk, SIOCOUTQ, &state->outq_len))
+		test_error("ioctl(SIOCOUTQ)");
+
+	if (ioctl(sk, SIOCOUTQNSD, &state->outq_nsd_len))
+		test_error("ioctl(SIOCOUTQNSD)");
+	test_sock_checkpoint_queue(sk, TCP_SEND_QUEUE, state->outq_len, &state->out);
+
+	if (ioctl(sk, SIOCINQ, &state->inq_len))
+		test_error("ioctl(SIOCINQ)");
+	test_sock_checkpoint_queue(sk, TCP_RECV_QUEUE, state->inq_len, &state->in);
+
+	if (state->info.tcpi_state == TCP_CLOSE)
+		state->outq_len = state->outq_nsd_len = 0;
+
+	len = sizeof(state->mss);
+	ret = getsockopt(sk, SOL_TCP, TCP_MAXSEG, &state->mss, &len);
+	if (ret || len != sizeof(state->mss))
+		test_error("getsockopt(TCP_MAXSEG): %d", (int)len);
+
+	len = sizeof(state->timestamp);
+	ret = getsockopt(sk, SOL_TCP, TCP_TIMESTAMP, &state->timestamp, &len);
+	if (ret || len != sizeof(state->timestamp))
+		test_error("getsockopt(TCP_TIMESTAMP): %d", (int)len);
+}
+
+void test_ao_checkpoint(int sk, struct tcp_ao_repair *state)
+{
+	socklen_t len = sizeof(*state);
+	int ret;
+
+	memset(state, 0, sizeof(*state));
+
+	ret = getsockopt(sk, SOL_TCP, TCP_AO_REPAIR, state, &len);
+	if (ret || len != sizeof(*state))
+		test_error("getsockopt(TCP_AO_REPAIR): %d", (int)len);
+}
+
+static void test_sock_restore_seq(int sk, int queue, uint32_t seq)
+{
+	if (setsockopt(sk, SOL_TCP, TCP_REPAIR_QUEUE, &queue, sizeof(queue)))
+		test_error("setsockopt(TCP_REPAIR_QUEUE)");
+
+	if (setsockopt(sk, SOL_TCP, TCP_QUEUE_SEQ, &seq, sizeof(seq)))
+		test_error("setsockopt(TCP_QUEUE_SEQ)");
+}
+
+static void test_sock_restore_queue(int sk, int queue, void *buf, int len)
+{
+	int chunk = len;
+	size_t off = 0;
+
+	if (len == 0)
+		return;
+
+	if (setsockopt(sk, SOL_TCP, TCP_REPAIR_QUEUE, &queue, sizeof(queue)))
+		test_error("setsockopt(TCP_REPAIR_QUEUE)");
+
+	do {
+		int ret;
+
+		ret = send(sk, buf + off, chunk, 0);
+		if (ret <= 0) {
+			if (chunk > 1024) {
+				chunk >>= 1;
+				continue;
+			}
+			test_error("send()");
+		}
+		off += ret;
+		len -= ret;
+	} while (len > 0);
+}
+
+void __test_sock_restore(int sk, const char *device,
+			 struct tcp_sock_state *state,
+			 void *saddr, void *daddr, size_t addr_size)
+{
+	struct tcp_repair_opt opts[4];
+	unsigned int opt_nr = 0;
+	long flags;
+
+	if (bind(sk, saddr, addr_size))
+		test_error("bind()");
+
+	flags = fcntl(sk, F_GETFL);
+	if ((flags < 0) || (fcntl(sk, F_SETFL, flags | O_NONBLOCK) < 0))
+		test_error("fcntl()");
+
+	test_sock_restore_seq(sk, TCP_RECV_QUEUE, state->in.seq - state->inq_len);
+	test_sock_restore_seq(sk, TCP_SEND_QUEUE, state->out.seq - state->outq_len);
+
+	if (device != NULL && setsockopt(sk, SOL_SOCKET, SO_BINDTODEVICE,
+					 device, strlen(device) + 1))
+		test_error("setsockopt(SO_BINDTODEVICE, %s)", device);
+
+	if (connect(sk, daddr, addr_size))
+		test_error("connect()");
+
+	if (state->info.tcpi_options & TCPI_OPT_SACK) {
+		opts[opt_nr].opt_code = TCPOPT_SACK_PERMITTED;
+		opts[opt_nr].opt_val = 0;
+		opt_nr++;
+	}
+	if (state->info.tcpi_options & TCPI_OPT_WSCALE) {
+		opts[opt_nr].opt_code = TCPOPT_WINDOW;
+		opts[opt_nr].opt_val = state->info.tcpi_snd_wscale +
+				(state->info.tcpi_rcv_wscale << 16);
+		opt_nr++;
+	}
+	if (state->info.tcpi_options & TCPI_OPT_TIMESTAMPS) {
+		opts[opt_nr].opt_code = TCPOPT_TIMESTAMP;
+		opts[opt_nr].opt_val = 0;
+		opt_nr++;
+	}
+	opts[opt_nr].opt_code = TCPOPT_MAXSEG;
+	opts[opt_nr].opt_val = state->mss;
+	opt_nr++;
+
+	if (setsockopt(sk, SOL_TCP, TCP_REPAIR_OPTIONS, opts, opt_nr * sizeof(opts[0])))
+		test_error("setsockopt(TCP_REPAIR_OPTIONS)");
+
+	if (state->info.tcpi_options & TCPI_OPT_TIMESTAMPS) {
+		if (setsockopt(sk, SOL_TCP, TCP_TIMESTAMP,
+			       &state->timestamp, opt_nr * sizeof(opts[0])))
+			test_error("setsockopt(TCP_TIMESTAMP)");
+	}
+	test_sock_restore_queue(sk, TCP_RECV_QUEUE, state->in.buf, state->inq_len);
+	test_sock_restore_queue(sk, TCP_SEND_QUEUE, state->out.buf, state->outq_len);
+	if (setsockopt(sk, SOL_TCP, TCP_REPAIR_WINDOW, &state->trw, sizeof(state->trw)))
+		test_error("setsockopt(TCP_REPAIR_WINDOW)");
+}
+
+void test_ao_restore(int sk, struct tcp_ao_repair *state)
+{
+	if (setsockopt(sk, SOL_TCP, TCP_AO_REPAIR, state, sizeof(*state)))
+		test_error("setsockopt(TCP_AO_REPAIR)");
+}
+
+void test_sock_state_free(struct tcp_sock_state *state)
+{
+	free(state->out.buf);
+	free(state->in.buf);
+}
+
+void test_enable_repair(int sk)
+{
+	int val = TCP_REPAIR_ON;
+
+	if (setsockopt(sk, SOL_TCP, TCP_REPAIR, &val, sizeof(val)))
+		test_error("setsockopt(TCP_REPAIR)");
+}
+
+void test_disable_repair(int sk)
+{
+	int val = TCP_REPAIR_OFF_NO_WP;
+
+	if (setsockopt(sk, SOL_TCP, TCP_REPAIR, &val, sizeof(val)))
+		test_error("setsockopt(TCP_REPAIR)");
+}
+
+void test_kill_sk(int sk)
+{
+	test_enable_repair(sk);
+	close(sk);
+}