Merge branch 'Retire test_sock.c'

Jordan Rife says:

====================
This patch series migrates test cases out of test_sock.c to
prog_tests-style tests. It moves all BPF_CGROUP_INET4_POST_BIND and
BPF_CGROUP_INET6_POST_BIND test cases into a new prog_test,
sock_post_bind.c, while reimplementing all LOAD_REJECT test cases as
verifier tests in progs/verifier_sock.c. Finally, it moves remaining
BPF_CGROUP_INET_SOCK_CREATE test coverage into prog_tests/sock_create.c
before retiring test_sock.c completely.

Changes
=======
v1->v2:
- Remove superfluous verbose bool from the top of sock_post_bind.c.
- Use ASSERT_OK_FD instead of ASSERT_GE to test cgroup_fd validity.
- Run sock_post_bind tests in their own namespace, "sock_post_bind".
====================

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>

2 files changed, 451 insertions, 10 deletions

diff --git a/tools/testing/selftests/bpf/prog_tests/sock_create.c b/tools/testing/selftests/bpf/prog_tests/sock_create.c
index 17a3713621dd..187ffc5e60c4 100644
--- a/tools/testing/selftests/bpf/prog_tests/sock_create.c
+++ b/tools/testing/selftests/bpf/prog_tests/sock_create.c
@@ -237,6 +237,19 @@ static struct sock_create_test {
 
 		.error = DENY_CREATE,
 	},
+	{
+		.descr = "load w/o expected_attach_type (compat mode)",
+		.insns = {
+			/* return 1 */
+			BPF_MOV64_IMM(BPF_REG_0, 1),
+			BPF_EXIT_INSN(),
+		},
+		.expected_attach_type = 0,
+		.attach_type = BPF_CGROUP_INET_SOCK_CREATE,
+
+		.domain = AF_INET,
+		.type = SOCK_STREAM,
+	},
 };
 
 static int load_prog(const struct bpf_insn *insns,
@@ -291,16 +304,18 @@ static int run_test(int cgroup_fd, struct sock_create_test *test)
 		goto detach_prog;
 	}
 
-	err = getsockopt(sock_fd, SOL_SOCKET, test->optname, &optval, &optlen);
-	if (err) {
-		log_err("Failed to call getsockopt");
-		goto cleanup;
-	}
-
-	if (optval != test->optval) {
-		errno = 0;
-		log_err("getsockopt returned unexpected optval");
-		goto cleanup;
+	if (test->optname) {
+		err = getsockopt(sock_fd, SOL_SOCKET, test->optname, &optval, &optlen);
+		if (err) {
+			log_err("Failed to call getsockopt");
+			goto cleanup;
+		}
+
+		if (optval != test->optval) {
+			errno = 0;
+			log_err("getsockopt returned unexpected optval");
+			goto cleanup;
+		}
 	}
 
 	ret = test->error != OK;
diff --git a/tools/testing/selftests/bpf/prog_tests/sock_post_bind.c b/tools/testing/selftests/bpf/prog_tests/sock_post_bind.c
new file mode 100644
index 000000000000..788135c9c673
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/sock_post_bind.c
@@ -0,0 +1,426 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/bpf.h>
+#include <test_progs.h>
+#include "cgroup_helpers.h"
+
+#define TEST_NS "sock_post_bind"
+
+static char bpf_log_buf[4096];
+
+static struct sock_post_bind_test {
+	const char			*descr;
+	/* BPF prog properties */
+	const struct bpf_insn		insns[64];
+	enum bpf_attach_type		attach_type;
+	enum bpf_attach_type		expected_attach_type;
+	/* Socket properties */
+	int				domain;
+	int				type;
+	/* Endpoint to bind() to */
+	const char *ip;
+	unsigned short port;
+	unsigned short port_retry;
+
+	/* Expected test result */
+	enum {
+		ATTACH_REJECT,
+		BIND_REJECT,
+		SUCCESS,
+		RETRY_SUCCESS,
+		RETRY_REJECT
+	} result;
+} tests[] = {
+	{
+		.descr = "attach type mismatch bind4 vs bind6",
+		.insns = {
+			BPF_MOV64_IMM(BPF_REG_0, 1),
+			BPF_EXIT_INSN(),
+		},
+		.expected_attach_type = BPF_CGROUP_INET4_POST_BIND,
+		.attach_type = BPF_CGROUP_INET6_POST_BIND,
+		.result = ATTACH_REJECT,
+	},
+	{
+		.descr = "attach type mismatch bind6 vs bind4",
+		.insns = {
+			BPF_MOV64_IMM(BPF_REG_0, 1),
+			BPF_EXIT_INSN(),
+		},
+		.expected_attach_type = BPF_CGROUP_INET6_POST_BIND,
+		.attach_type = BPF_CGROUP_INET4_POST_BIND,
+		.result = ATTACH_REJECT,
+	},
+	{
+		.descr = "attach type mismatch default vs bind4",
+		.insns = {
+			BPF_MOV64_IMM(BPF_REG_0, 1),
+			BPF_EXIT_INSN(),
+		},
+		.expected_attach_type = 0,
+		.attach_type = BPF_CGROUP_INET4_POST_BIND,
+		.result = ATTACH_REJECT,
+	},
+	{
+		.descr = "attach type mismatch bind6 vs sock_create",
+		.insns = {
+			BPF_MOV64_IMM(BPF_REG_0, 1),
+			BPF_EXIT_INSN(),
+		},
+		.expected_attach_type = BPF_CGROUP_INET6_POST_BIND,
+		.attach_type = BPF_CGROUP_INET_SOCK_CREATE,
+		.result = ATTACH_REJECT,
+	},
+	{
+		.descr = "bind4 reject all",
+		.insns = {
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.expected_attach_type = BPF_CGROUP_INET4_POST_BIND,
+		.attach_type = BPF_CGROUP_INET4_POST_BIND,
+		.domain = AF_INET,
+		.type = SOCK_STREAM,
+		.ip = "0.0.0.0",
+		.result = BIND_REJECT,
+	},
+	{
+		.descr = "bind6 reject all",
+		.insns = {
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.expected_attach_type = BPF_CGROUP_INET6_POST_BIND,
+		.attach_type = BPF_CGROUP_INET6_POST_BIND,
+		.domain = AF_INET6,
+		.type = SOCK_STREAM,
+		.ip = "::",
+		.result = BIND_REJECT,
+	},
+	{
+		.descr = "bind6 deny specific IP & port",
+		.insns = {
+			BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
+
+			/* if (ip == expected && port == expected) */
+			BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_6,
+				    offsetof(struct bpf_sock, src_ip6[3])),
+			BPF_JMP_IMM(BPF_JNE, BPF_REG_7,
+				    __bpf_constant_ntohl(0x00000001), 4),
+			BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_6,
+				    offsetof(struct bpf_sock, src_port)),
+			BPF_JMP_IMM(BPF_JNE, BPF_REG_7, 0x2001, 2),
+
+			/* return DENY; */
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_JMP_A(1),
+
+			/* else return ALLOW; */
+			BPF_MOV64_IMM(BPF_REG_0, 1),
+			BPF_EXIT_INSN(),
+		},
+		.expected_attach_type = BPF_CGROUP_INET6_POST_BIND,
+		.attach_type = BPF_CGROUP_INET6_POST_BIND,
+		.domain = AF_INET6,
+		.type = SOCK_STREAM,
+		.ip = "::1",
+		.port = 8193,
+		.result = BIND_REJECT,
+	},
+	{
+		.descr = "bind4 allow specific IP & port",
+		.insns = {
+			BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
+
+			/* if (ip == expected && port == expected) */
+			BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_6,
+				    offsetof(struct bpf_sock, src_ip4)),
+			BPF_JMP_IMM(BPF_JNE, BPF_REG_7,
+				    __bpf_constant_ntohl(0x7F000001), 4),
+			BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_6,
+				    offsetof(struct bpf_sock, src_port)),
+			BPF_JMP_IMM(BPF_JNE, BPF_REG_7, 0x1002, 2),
+
+			/* return ALLOW; */
+			BPF_MOV64_IMM(BPF_REG_0, 1),
+			BPF_JMP_A(1),
+
+			/* else return DENY; */
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.expected_attach_type = BPF_CGROUP_INET4_POST_BIND,
+		.attach_type = BPF_CGROUP_INET4_POST_BIND,
+		.domain = AF_INET,
+		.type = SOCK_STREAM,
+		.ip = "127.0.0.1",
+		.port = 4098,
+		.result = SUCCESS,
+	},
+	{
+		.descr = "bind4 deny specific IP & port of TCP, and retry",
+		.insns = {
+			BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
+
+			/* if (ip == expected && port == expected) */
+			BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_6,
+				    offsetof(struct bpf_sock, src_ip4)),
+			BPF_JMP_IMM(BPF_JNE, BPF_REG_7,
+				    __bpf_constant_ntohl(0x7F000001), 4),
+			BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_6,
+				    offsetof(struct bpf_sock, src_port)),
+			BPF_JMP_IMM(BPF_JNE, BPF_REG_7, 0x1002, 2),
+
+			/* return DENY; */
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_JMP_A(1),
+
+			/* else return ALLOW; */
+			BPF_MOV64_IMM(BPF_REG_0, 1),
+			BPF_EXIT_INSN(),
+		},
+		.expected_attach_type = BPF_CGROUP_INET4_POST_BIND,
+		.attach_type = BPF_CGROUP_INET4_POST_BIND,
+		.domain = AF_INET,
+		.type = SOCK_STREAM,
+		.ip = "127.0.0.1",
+		.port = 4098,
+		.port_retry = 5000,
+		.result = RETRY_SUCCESS,
+	},
+	{
+		.descr = "bind4 deny specific IP & port of UDP, and retry",
+		.insns = {
+			BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
+
+			/* if (ip == expected && port == expected) */
+			BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_6,
+				    offsetof(struct bpf_sock, src_ip4)),
+			BPF_JMP_IMM(BPF_JNE, BPF_REG_7,
+				    __bpf_constant_ntohl(0x7F000001), 4),
+			BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_6,
+				    offsetof(struct bpf_sock, src_port)),
+			BPF_JMP_IMM(BPF_JNE, BPF_REG_7, 0x1002, 2),
+
+			/* return DENY; */
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_JMP_A(1),
+
+			/* else return ALLOW; */
+			BPF_MOV64_IMM(BPF_REG_0, 1),
+			BPF_EXIT_INSN(),
+		},
+		.expected_attach_type = BPF_CGROUP_INET4_POST_BIND,
+		.attach_type = BPF_CGROUP_INET4_POST_BIND,
+		.domain = AF_INET,
+		.type = SOCK_DGRAM,
+		.ip = "127.0.0.1",
+		.port = 4098,
+		.port_retry = 5000,
+		.result = RETRY_SUCCESS,
+	},
+	{
+		.descr = "bind6 deny specific IP & port, and retry",
+		.insns = {
+			BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
+
+			/* if (ip == expected && port == expected) */
+			BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_6,
+				    offsetof(struct bpf_sock, src_ip6[3])),
+			BPF_JMP_IMM(BPF_JNE, BPF_REG_7,
+				    __bpf_constant_ntohl(0x00000001), 4),
+			BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_6,
+				    offsetof(struct bpf_sock, src_port)),
+			BPF_JMP_IMM(BPF_JNE, BPF_REG_7, 0x2001, 2),
+
+			/* return DENY; */
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_JMP_A(1),
+
+			/* else return ALLOW; */
+			BPF_MOV64_IMM(BPF_REG_0, 1),
+			BPF_EXIT_INSN(),
+		},
+		.expected_attach_type = BPF_CGROUP_INET6_POST_BIND,
+		.attach_type = BPF_CGROUP_INET6_POST_BIND,
+		.domain = AF_INET6,
+		.type = SOCK_STREAM,
+		.ip = "::1",
+		.port = 8193,
+		.port_retry = 9000,
+		.result = RETRY_SUCCESS,
+	},
+	{
+		.descr = "bind4 allow all",
+		.insns = {
+			BPF_MOV64_IMM(BPF_REG_0, 1),
+			BPF_EXIT_INSN(),
+		},
+		.expected_attach_type = BPF_CGROUP_INET4_POST_BIND,
+		.attach_type = BPF_CGROUP_INET4_POST_BIND,
+		.domain = AF_INET,
+		.type = SOCK_STREAM,
+		.ip = "0.0.0.0",
+		.result = SUCCESS,
+	},
+	{
+		.descr = "bind6 allow all",
+		.insns = {
+			BPF_MOV64_IMM(BPF_REG_0, 1),
+			BPF_EXIT_INSN(),
+		},
+		.expected_attach_type = BPF_CGROUP_INET6_POST_BIND,
+		.attach_type = BPF_CGROUP_INET6_POST_BIND,
+		.domain = AF_INET6,
+		.type = SOCK_STREAM,
+		.ip = "::",
+		.result = SUCCESS,
+	},
+};
+
+static int load_prog(const struct bpf_insn *insns,
+		     enum bpf_attach_type expected_attach_type)
+{
+	LIBBPF_OPTS(bpf_prog_load_opts, opts,
+		    .expected_attach_type = expected_attach_type,
+		    .log_level = 2,
+		    .log_buf = bpf_log_buf,
+		    .log_size = sizeof(bpf_log_buf),
+	);
+	int fd, insns_cnt = 0;
+
+	for (;
+	     insns[insns_cnt].code != (BPF_JMP | BPF_EXIT);
+	     insns_cnt++) {
+	}
+	insns_cnt++;
+
+	fd = bpf_prog_load(BPF_PROG_TYPE_CGROUP_SOCK, NULL, "GPL", insns,
+			   insns_cnt, &opts);
+	if (fd < 0)
+		fprintf(stderr, "%s\n", bpf_log_buf);
+
+	return fd;
+}
+
+static int bind_sock(int domain, int type, const char *ip,
+		     unsigned short port, unsigned short port_retry)
+{
+	struct sockaddr_storage addr;
+	struct sockaddr_in6 *addr6;
+	struct sockaddr_in *addr4;
+	int sockfd = -1;
+	socklen_t len;
+	int res = SUCCESS;
+
+	sockfd = socket(domain, type, 0);
+	if (sockfd < 0)
+		goto err;
+
+	memset(&addr, 0, sizeof(addr));
+
+	if (domain == AF_INET) {
+		len = sizeof(struct sockaddr_in);
+		addr4 = (struct sockaddr_in *)&addr;
+		addr4->sin_family = domain;
+		addr4->sin_port = htons(port);
+		if (inet_pton(domain, ip, (void *)&addr4->sin_addr) != 1)
+			goto err;
+	} else if (domain == AF_INET6) {
+		len = sizeof(struct sockaddr_in6);
+		addr6 = (struct sockaddr_in6 *)&addr;
+		addr6->sin6_family = domain;
+		addr6->sin6_port = htons(port);
+		if (inet_pton(domain, ip, (void *)&addr6->sin6_addr) != 1)
+			goto err;
+	} else {
+		goto err;
+	}
+
+	if (bind(sockfd, (const struct sockaddr *)&addr, len) == -1) {
+		/* sys_bind() may fail for different reasons, errno has to be
+		 * checked to confirm that BPF program rejected it.
+		 */
+		if (errno != EPERM)
+			goto err;
+		if (port_retry)
+			goto retry;
+		res = BIND_REJECT;
+		goto out;
+	}
+
+	goto out;
+retry:
+	if (domain == AF_INET)
+		addr4->sin_port = htons(port_retry);
+	else
+		addr6->sin6_port = htons(port_retry);
+	if (bind(sockfd, (const struct sockaddr *)&addr, len) == -1) {
+		if (errno != EPERM)
+			goto err;
+		res = RETRY_REJECT;
+	} else {
+		res = RETRY_SUCCESS;
+	}
+	goto out;
+err:
+	res = -1;
+out:
+	close(sockfd);
+	return res;
+}
+
+static int run_test(int cgroup_fd, struct sock_post_bind_test *test)
+{
+	int err, prog_fd, res, ret = 0;
+
+	prog_fd = load_prog(test->insns, test->expected_attach_type);
+	if (prog_fd < 0)
+		goto err;
+
+	err = bpf_prog_attach(prog_fd, cgroup_fd, test->attach_type, 0);
+	if (err < 0) {
+		if (test->result == ATTACH_REJECT)
+			goto out;
+		else
+			goto err;
+	}
+
+	res = bind_sock(test->domain, test->type, test->ip, test->port,
+			test->port_retry);
+	if (res > 0 && test->result == res)
+		goto out;
+err:
+	ret = -1;
+out:
+	/* Detaching w/o checking return code: best effort attempt. */
+	if (prog_fd != -1)
+		bpf_prog_detach(cgroup_fd, test->attach_type);
+	close(prog_fd);
+	return ret;
+}
+
+void test_sock_post_bind(void)
+{
+	struct netns_obj *ns;
+	int cgroup_fd;
+	int i;
+
+	cgroup_fd = test__join_cgroup("/post_bind");
+	if (!ASSERT_OK_FD(cgroup_fd, "join_cgroup"))
+		return;
+
+	ns = netns_new(TEST_NS, true);
+	if (!ASSERT_OK_PTR(ns, "netns_new"))
+		goto cleanup;
+
+	for (i = 0; i < ARRAY_SIZE(tests); i++) {
+		if (!test__start_subtest(tests[i].descr))
+			continue;
+
+		ASSERT_OK(run_test(cgroup_fd, &tests[i]), tests[i].descr);
+	}
+
+cleanup:
+	netns_free(ns);
+	close(cgroup_fd);
+}