1 files changed, 470 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/network_helpers.c b/tools/testing/selftests/bpf/network_helpers.c
new file mode 100644
index 000000000..1fa467238
--- /dev/null
+++ b/tools/testing/selftests/bpf/network_helpers.c
@@ -0,0 +1,470 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#define _GNU_SOURCE
+
+#include <errno.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <sched.h>
+
+#include <arpa/inet.h>
+#include <sys/mount.h>
+#include <sys/stat.h>
+
+#include <linux/err.h>
+#include <linux/in.h>
+#include <linux/in6.h>
+#include <linux/limits.h>
+
+#include "bpf_util.h"
+#include "network_helpers.h"
+#include "test_progs.h"
+
+#ifndef IPPROTO_MPTCP
+#define IPPROTO_MPTCP 262
+#endif
+
+#define clean_errno() (errno == 0 ? "None" : strerror(errno))
+#define log_err(MSG, ...) ({						\
+			int __save = errno;				\
+			fprintf(stderr, "(%s:%d: errno: %s) " MSG "\n", \
+				__FILE__, __LINE__, clean_errno(),	\
+				##__VA_ARGS__);				\
+			errno = __save;					\
+})
+
+struct ipv4_packet pkt_v4 = {
+	.eth.h_proto = __bpf_constant_htons(ETH_P_IP),
+	.iph.ihl = 5,
+	.iph.protocol = IPPROTO_TCP,
+	.iph.tot_len = __bpf_constant_htons(MAGIC_BYTES),
+	.tcp.urg_ptr = 123,
+	.tcp.doff = 5,
+};
+
+struct ipv6_packet pkt_v6 = {
+	.eth.h_proto = __bpf_constant_htons(ETH_P_IPV6),
+	.iph.nexthdr = IPPROTO_TCP,
+	.iph.payload_len = __bpf_constant_htons(MAGIC_BYTES),
+	.tcp.urg_ptr = 123,
+	.tcp.doff = 5,
+};
+
+int settimeo(int fd, int timeout_ms)
+{
+	struct timeval timeout = { .tv_sec = 3 };
+
+	if (timeout_ms > 0) {
+		timeout.tv_sec = timeout_ms / 1000;
+		timeout.tv_usec = (timeout_ms % 1000) * 1000;
+	}
+
+	if (setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, &timeout,
+		       sizeof(timeout))) {
+		log_err("Failed to set SO_RCVTIMEO");
+		return -1;
+	}
+
+	if (setsockopt(fd, SOL_SOCKET, SO_SNDTIMEO, &timeout,
+		       sizeof(timeout))) {
+		log_err("Failed to set SO_SNDTIMEO");
+		return -1;
+	}
+
+	return 0;
+}
+
+#define save_errno_close(fd) ({ int __save = errno; close(fd); errno = __save; })
+
+static int __start_server(int type, int protocol, const struct sockaddr *addr,
+			  socklen_t addrlen, int timeout_ms, bool reuseport)
+{
+	int on = 1;
+	int fd;
+
+	fd = socket(addr->sa_family, type, protocol);
+	if (fd < 0) {
+		log_err("Failed to create server socket");
+		return -1;
+	}
+
+	if (settimeo(fd, timeout_ms))
+		goto error_close;
+
+	if (reuseport &&
+	    setsockopt(fd, SOL_SOCKET, SO_REUSEPORT, &on, sizeof(on))) {
+		log_err("Failed to set SO_REUSEPORT");
+		goto error_close;
+	}
+
+	if (bind(fd, addr, addrlen) < 0) {
+		log_err("Failed to bind socket");
+		goto error_close;
+	}
+
+	if (type == SOCK_STREAM) {
+		if (listen(fd, 1) < 0) {
+			log_err("Failed to listed on socket");
+			goto error_close;
+		}
+	}
+
+	return fd;
+
+error_close:
+	save_errno_close(fd);
+	return -1;
+}
+
+static int start_server_proto(int family, int type, int protocol,
+			      const char *addr_str, __u16 port, int timeout_ms)
+{
+	struct sockaddr_storage addr;
+	socklen_t addrlen;
+
+	if (make_sockaddr(family, addr_str, port, &addr, &addrlen))
+		return -1;
+
+	return __start_server(type, protocol, (struct sockaddr *)&addr,
+			      addrlen, timeout_ms, false);
+}
+
+int start_server(int family, int type, const char *addr_str, __u16 port,
+		 int timeout_ms)
+{
+	return start_server_proto(family, type, 0, addr_str, port, timeout_ms);
+}
+
+int start_mptcp_server(int family, const char *addr_str, __u16 port,
+		       int timeout_ms)
+{
+	return start_server_proto(family, SOCK_STREAM, IPPROTO_MPTCP, addr_str,
+				  port, timeout_ms);
+}
+
+int *start_reuseport_server(int family, int type, const char *addr_str,
+			    __u16 port, int timeout_ms, unsigned int nr_listens)
+{
+	struct sockaddr_storage addr;
+	unsigned int nr_fds = 0;
+	socklen_t addrlen;
+	int *fds;
+
+	if (!nr_listens)
+		return NULL;
+
+	if (make_sockaddr(family, addr_str, port, &addr, &addrlen))
+		return NULL;
+
+	fds = malloc(sizeof(*fds) * nr_listens);
+	if (!fds)
+		return NULL;
+
+	fds[0] = __start_server(type, 0, (struct sockaddr *)&addr, addrlen,
+				timeout_ms, true);
+	if (fds[0] == -1)
+		goto close_fds;
+	nr_fds = 1;
+
+	if (getsockname(fds[0], (struct sockaddr *)&addr, &addrlen))
+		goto close_fds;
+
+	for (; nr_fds < nr_listens; nr_fds++) {
+		fds[nr_fds] = __start_server(type, 0, (struct sockaddr *)&addr,
+					     addrlen, timeout_ms, true);
+		if (fds[nr_fds] == -1)
+			goto close_fds;
+	}
+
+	return fds;
+
+close_fds:
+	free_fds(fds, nr_fds);
+	return NULL;
+}
+
+void free_fds(int *fds, unsigned int nr_close_fds)
+{
+	if (fds) {
+		while (nr_close_fds)
+			close(fds[--nr_close_fds]);
+		free(fds);
+	}
+}
+
+int fastopen_connect(int server_fd, const char *data, unsigned int data_len,
+		     int timeout_ms)
+{
+	struct sockaddr_storage addr;
+	socklen_t addrlen = sizeof(addr);
+	struct sockaddr_in *addr_in;
+	int fd, ret;
+
+	if (getsockname(server_fd, (struct sockaddr *)&addr, &addrlen)) {
+		log_err("Failed to get server addr");
+		return -1;
+	}
+
+	addr_in = (struct sockaddr_in *)&addr;
+	fd = socket(addr_in->sin_family, SOCK_STREAM, 0);
+	if (fd < 0) {
+		log_err("Failed to create client socket");
+		return -1;
+	}
+
+	if (settimeo(fd, timeout_ms))
+		goto error_close;
+
+	ret = sendto(fd, data, data_len, MSG_FASTOPEN, (struct sockaddr *)&addr,
+		     addrlen);
+	if (ret != data_len) {
+		log_err("sendto(data, %u) != %d\n", data_len, ret);
+		goto error_close;
+	}
+
+	return fd;
+
+error_close:
+	save_errno_close(fd);
+	return -1;
+}
+
+static int connect_fd_to_addr(int fd,
+			      const struct sockaddr_storage *addr,
+			      socklen_t addrlen, const bool must_fail)
+{
+	int ret;
+
+	errno = 0;
+	ret = connect(fd, (const struct sockaddr *)addr, addrlen);
+	if (must_fail) {
+		if (!ret) {
+			log_err("Unexpected success to connect to server");
+			return -1;
+		}
+		if (errno != EPERM) {
+			log_err("Unexpected error from connect to server");
+			return -1;
+		}
+	} else {
+		if (ret) {
+			log_err("Failed to connect to server");
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+static const struct network_helper_opts default_opts;
+
+int connect_to_fd_opts(int server_fd, const struct network_helper_opts *opts)
+{
+	struct sockaddr_storage addr;
+	struct sockaddr_in *addr_in;
+	socklen_t addrlen, optlen;
+	int fd, type, protocol;
+
+	if (!opts)
+		opts = &default_opts;
+
+	optlen = sizeof(type);
+	if (getsockopt(server_fd, SOL_SOCKET, SO_TYPE, &type, &optlen)) {
+		log_err("getsockopt(SOL_TYPE)");
+		return -1;
+	}
+
+	if (getsockopt(server_fd, SOL_SOCKET, SO_PROTOCOL, &protocol, &optlen)) {
+		log_err("getsockopt(SOL_PROTOCOL)");
+		return -1;
+	}
+
+	addrlen = sizeof(addr);
+	if (getsockname(server_fd, (struct sockaddr *)&addr, &addrlen)) {
+		log_err("Failed to get server addr");
+		return -1;
+	}
+
+	addr_in = (struct sockaddr_in *)&addr;
+	fd = socket(addr_in->sin_family, type, protocol);
+	if (fd < 0) {
+		log_err("Failed to create client socket");
+		return -1;
+	}
+
+	if (settimeo(fd, opts->timeout_ms))
+		goto error_close;
+
+	if (opts->cc && opts->cc[0] &&
+	    setsockopt(fd, SOL_TCP, TCP_CONGESTION, opts->cc,
+		       strlen(opts->cc) + 1))
+		goto error_close;
+
+	if (connect_fd_to_addr(fd, &addr, addrlen, opts->must_fail))
+		goto error_close;
+
+	return fd;
+
+error_close:
+	save_errno_close(fd);
+	return -1;
+}
+
+int connect_to_fd(int server_fd, int timeout_ms)
+{
+	struct network_helper_opts opts = {
+		.timeout_ms = timeout_ms,
+	};
+
+	return connect_to_fd_opts(server_fd, &opts);
+}
+
+int connect_fd_to_fd(int client_fd, int server_fd, int timeout_ms)
+{
+	struct sockaddr_storage addr;
+	socklen_t len = sizeof(addr);
+
+	if (settimeo(client_fd, timeout_ms))
+		return -1;
+
+	if (getsockname(server_fd, (struct sockaddr *)&addr, &len)) {
+		log_err("Failed to get server addr");
+		return -1;
+	}
+
+	if (connect_fd_to_addr(client_fd, &addr, len, false))
+		return -1;
+
+	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;
+
+		memset(addr, 0, sizeof(*sin));
+		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;
+
+		memset(addr, 0, sizeof(*sin6));
+		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;
+}
+
+char *ping_command(int family)
+{
+	if (family == AF_INET6) {
+		/* On some systems 'ping' doesn't support IPv6, so use ping6 if it is present. */
+		if (!system("which ping6 >/dev/null 2>&1"))
+			return "ping6";
+		else
+			return "ping -6";
+	}
+	return "ping";
+}
+
+struct nstoken {
+	int orig_netns_fd;
+};
+
+static int setns_by_fd(int nsfd)
+{
+	int err;
+
+	err = setns(nsfd, CLONE_NEWNET);
+	close(nsfd);
+
+	if (!ASSERT_OK(err, "setns"))
+		return err;
+
+	/* Switch /sys to the new namespace so that e.g. /sys/class/net
+	 * reflects the devices in the new namespace.
+	 */
+	err = unshare(CLONE_NEWNS);
+	if (!ASSERT_OK(err, "unshare"))
+		return err;
+
+	/* Make our /sys mount private, so the following umount won't
+	 * trigger the global umount in case it's shared.
+	 */
+	err = mount("none", "/sys", NULL, MS_PRIVATE, NULL);
+	if (!ASSERT_OK(err, "remount private /sys"))
+		return err;
+
+	err = umount2("/sys", MNT_DETACH);
+	if (!ASSERT_OK(err, "umount2 /sys"))
+		return err;
+
+	err = mount("sysfs", "/sys", "sysfs", 0, NULL);
+	if (!ASSERT_OK(err, "mount /sys"))
+		return err;
+
+	err = mount("bpffs", "/sys/fs/bpf", "bpf", 0, NULL);
+	if (!ASSERT_OK(err, "mount /sys/fs/bpf"))
+		return err;
+
+	err = mount("debugfs", "/sys/kernel/debug", "debugfs", 0, NULL);
+	if (!ASSERT_OK(err, "mount /sys/kernel/debug"))
+		return err;
+
+	return 0;
+}
+
+struct nstoken *open_netns(const char *name)
+{
+	int nsfd;
+	char nspath[PATH_MAX];
+	int err;
+	struct nstoken *token;
+
+	token = calloc(1, sizeof(struct nstoken));
+	if (!ASSERT_OK_PTR(token, "malloc token"))
+		return NULL;
+
+	token->orig_netns_fd = open("/proc/self/ns/net", O_RDONLY);
+	if (!ASSERT_GE(token->orig_netns_fd, 0, "open /proc/self/ns/net"))
+		goto fail;
+
+	snprintf(nspath, sizeof(nspath), "%s/%s", "/var/run/netns", name);
+	nsfd = open(nspath, O_RDONLY | O_CLOEXEC);
+	if (!ASSERT_GE(nsfd, 0, "open netns fd"))
+		goto fail;
+
+	err = setns_by_fd(nsfd);
+	if (!ASSERT_OK(err, "setns_by_fd"))
+		goto fail;
+
+	return token;
+fail:
+	free(token);
+	return NULL;
+}
+
+void close_netns(struct nstoken *token)
+{
+	ASSERT_OK(setns_by_fd(token->orig_netns_fd), "setns_by_fd");
+	free(token);
+}