Add netlink regression test and gVisor test

test/Makefile

@@ -70,6 +70,9 @@ $(INITRAMFS)/lib/x86_64-linux-gnu: | $(VDSO_LIB)
 	@cp -L /lib/x86_64-linux-gnu/libevent-2.1.so.7 $@
 	@# required for VDSO
 	@cp -L $(VDSO_LIB) $@
+	@# required for netlink test
+	@cp -L /lib/x86_64-linux-gnu/libnl-3.so.200 $@
+	@cp -L /lib/x86_64-linux-gnu/libnl-route-3.so.200 $@
 
 $(VDSO_LIB): | $(VDSO_DIR) $(BINARY_CACHE_DIR)/vdso64.so
 	@# TODO: use a custom compiled vdso.so file in the future.

test/apps/network/Makefile

@@ -2,4 +2,4 @@
 
 include ../test_common.mk
 
-EXTRA_C_FLAGS :=
+EXTRA_C_FLAGS := -I/usr/include/libnl3 -lnl-3 -lnl-route-3

test/apps/network/netlink_route.c

@@ -0,0 +1,227 @@
+// SPDX-License-Identifier: MPL-2.0
+
+#include <netlink/netlink.h>
+#include <netlink/route/link.h>
+#include <netlink/route/addr.h>
+#include <net/if.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "test.h"
+
+#define ETHER_NAME "eth0"
+#define LOOPBACK_NAME "lo"
+
+#define SUCC(expr) ((expr), 0)
+
+int find_lo_and_eth0_by_libc(struct if_nameindex *if_ni)
+{
+	int found_links = 0;
+
+	for (struct if_nameindex *i = if_ni;
+	     !(i->if_index == 0 && i->if_name == NULL); i++) {
+		if (strcmp(i->if_name, LOOPBACK_NAME) == 0) {
+			found_links++;
+		}
+
+		if (strcmp(i->if_name, ETHER_NAME) == 0) {
+			found_links++;
+		}
+	}
+
+	return found_links;
+}
+
+FN_TEST(if_nameindex)
+{
+	struct if_nameindex *if_ni;
+
+	CHECK_WITH(SUCC(if_ni = if_nameindex()), if_ni != NULL);
+
+	TEST_RES(find_lo_and_eth0_by_libc(if_ni), _ret == 2);
+
+	if_freenameindex(if_ni);
+}
+END_TEST()
+
+void find_lo_and_eth0_by_libnl(struct nl_object *obj, void *arg)
+{
+	int *found_links = (int *)arg;
+	struct rtnl_link *link = (struct rtnl_link *)obj;
+
+	if (strcmp(rtnl_link_get_name(link), LOOPBACK_NAME) == 0) {
+		*found_links += 1;
+	}
+
+	if (strcmp(rtnl_link_get_name(link), ETHER_NAME) == 0) {
+		*found_links += 1;
+	}
+}
+
+FN_TEST(get_link_by_libnl)
+{
+	struct nl_sock *sock;
+	struct nl_cache *link_cache;
+
+	// 1. Create netlink socket and connect
+	sock = nl_socket_alloc();
+	TEST_RES(nl_connect(sock, NETLINK_ROUTE), _ret >= 0);
+
+	// 2. Allocate and retrieve link cache
+	TEST_RES(rtnl_link_alloc_cache(sock, AF_UNSPEC, &link_cache),
+		 _ret >= 0);
+
+	// 3. Iterate over all links to find lo and eth0
+	int found_links = 0;
+	TEST_RES(SUCC(nl_cache_foreach(link_cache, find_lo_and_eth0_by_libnl,
+				       &found_links)),
+		 found_links == 2);
+
+	// 4. Cleanup
+	nl_cache_free(link_cache);
+	nl_close(sock);
+	nl_socket_free(sock);
+}
+END_TEST()
+
+void find_loopback_address(struct nl_object *obj, void *arg)
+{
+	int *found_loopback = (int *)arg;
+	struct rtnl_addr *addr = (struct rtnl_addr *)obj;
+	struct nl_addr *local;
+	char buf[INET_ADDRSTRLEN];
+
+	int family = rtnl_addr_get_family(addr);
+	if (family != AF_INET) {
+		return;
+	}
+
+	local = rtnl_addr_get_local(addr);
+	if (local) {
+		nl_addr2str(local, buf, sizeof(buf));
+		if (strcmp(buf, "127.0.0.1/8") == 0) {
+			*found_loopback = 1;
+		}
+	}
+}
+
+FN_TEST(get_loopback_address)
+{
+	struct nl_sock *sock;
+	struct nl_cache *addr_cache;
+
+	// 1. Create netlink socket and connect
+	sock = nl_socket_alloc();
+	TEST_RES(nl_connect(sock, NETLINK_ROUTE), _ret >= 0);
+
+	// 2. Allocate and retrieve address cache
+	TEST_RES(rtnl_addr_alloc_cache(sock, &addr_cache), _ret >= 0);
+
+	// 3. Iterate over all addresses to find loopback address
+	int found_loopback = 0;
+	TEST_RES(SUCC(nl_cache_foreach(addr_cache, find_loopback_address,
+				       &found_loopback)),
+		 found_loopback == 1);
+
+	// 4. Cleanup
+	nl_cache_free(addr_cache);
+	nl_close(sock);
+	nl_socket_free(sock);
+}
+END_TEST()
+
+int find_new_addr_until_done(char *buffer, size_t len, int *found_new_addr)
+{
+	struct nlmsghdr *nlh = (struct nlmsghdr *)buffer;
+
+	for (; NLMSG_OK(nlh, len); nlh = NLMSG_NEXT(nlh, len)) {
+		if (nlh->nlmsg_type == NLMSG_DONE) {
+			return *found_new_addr ? 1 : -1;
+		}
+
+		if (nlh->nlmsg_type == RTM_NEWADDR) {
+			*found_new_addr += 1;
+		} else {
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+FN_TEST(get_addr_error)
+{
+#define BUFFER_SIZE 8192
+
+	struct nl_req {
+		struct nlmsghdr hdr;
+		struct ifaddrmsg ifa;
+	};
+
+	int sock_fd;
+	struct sockaddr_nl sa;
+	char buffer[BUFFER_SIZE];
+
+	sock_fd = TEST_SUCC(socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE));
+
+	memset(&sa, 0, sizeof(sa));
+	sa.nl_family = AF_NETLINK;
+
+	TEST_SUCC(bind(sock_fd, (struct sockaddr *)&sa, sizeof(sa)));
+
+	// 1. Without NLM_F_DUMP flag
+	struct nl_req req;
+	memset(&req, 0, sizeof(req));
+	req.hdr.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifaddrmsg));
+	req.hdr.nlmsg_type = RTM_GETADDR;
+	req.hdr.nlmsg_flags = NLM_F_REQUEST;
+	req.hdr.nlmsg_seq = 1;
+	req.ifa.ifa_family = AF_UNSPEC;
+
+	struct iovec iov = { &req, req.hdr.nlmsg_len };
+	struct msghdr msg = { &sa, sizeof(sa), &iov, 1, NULL, 0, 0 };
+
+	TEST_SUCC(sendmsg(sock_fd, &msg, 0));
+	TEST_RES(recv(sock_fd, buffer, BUFFER_SIZE, 0),
+		 ((struct nlmsghdr *)buffer)->nlmsg_type == NLMSG_ERROR &&
+			 ((struct nlmsgerr *)NLMSG_DATA(buffer))->error ==
+				 -EOPNOTSUPP);
+
+	// 2. Invalid required index
+	req.hdr.nlmsg_flags = NLM_F_REQUEST | NLM_F_DUMP | NLM_F_ACK;
+	req.ifa.ifa_index = 9999;
+	TEST_SUCC(sendmsg(sock_fd, &msg, 0));
+
+	int found_new_addr = 0;
+	while (1) {
+		size_t recv_len =
+			TEST_SUCC(recv(sock_fd, buffer, BUFFER_SIZE, 0));
+
+		int found_done = TEST_SUCC(find_new_addr_until_done(
+			buffer, recv_len, &found_new_addr));
+
+		if (found_done != 0) {
+			break;
+		}
+	}
+
+	// 3. Invalid required family
+	req.ifa.ifa_family = 255;
+	req.ifa.ifa_index = 0;
+	TEST_SUCC(sendmsg(sock_fd, &msg, 0));
+
+	found_new_addr = 0;
+	while (1) {
+		size_t recv_len =
+			TEST_SUCC(recv(sock_fd, buffer, BUFFER_SIZE, 0));
+
+		int found_done = TEST_SUCC(find_new_addr_until_done(
+			buffer, recv_len, &found_new_addr));
+
+		if (found_done != 0) {
+			break;
+		}
+	}
+}
+END_TEST()

test/apps/test_common.mk

@@ -22,7 +22,7 @@ $(OBJ_OUTPUT_DIR) $(DEP_OUTPUT_DIR):
 	@mkdir -p $@
 
 $(OBJ_OUTPUT_DIR)/%: %.c | $(OBJ_OUTPUT_DIR) $(DEP_OUTPUT_DIR)
-	@$(CC) $(C_FLAGS) $(EXTRA_C_FLAGS) $< -o $@ \
+	@$(CC) $(C_FLAGS) $< -o $@ $(EXTRA_C_FLAGS) \
 		-MMD -MF $(DEP_OUTPUT_DIR)/$*.d
 	@echo "CC <= $@"
 

test/syscall_test/Makefile

@@ -46,6 +46,7 @@ TESTS ?= \
 	sigaction_test \
 	sigaltstack_test \
 	signalfd_test \
+	socket_netlink_route_test \
 	stat_test \
 	stat_times_test \
 	statfs_test \

test/syscall_test/blocklists/socket_netlink_route_test

@@ -0,0 +1,12 @@
+NetlinkRouteTest.MsgHdrMsgUnsuppType
+NetlinkRouteTest.MsgHdrMsgTrunc
+NetlinkRouteTest.MsgTruncMsgHdrMsgTrunc
+NetlinkRouteTest.ControlMessageIgnored
+NetlinkRouteTest.AddAddr
+NetlinkRouteTest.GetRouteDump
+NetlinkRouteTest.GetRouteRequest
+NetlinkRouteTest.RecvmsgTrunc
+NetlinkRouteTest.RecvmsgTruncPeek
+NetlinkRouteTest.NoPasscredNoCreds
+NetlinkRouteTest.PasscredCreds
+NetlinkRouteTest/SockOptTest.GetSockOpt/*