@@ -2,7 +2,7 @@
# Makefile for net selftests
CFLAGS = -Wall -Wl,--no-as-needed -O2 -g
-CFLAGS += -I../../../../usr/include/ $(KHDR_INCLUDES)
+CFLAGS += -I../../../../usr/include/ -I../../../include/ $(KHDR_INCLUDES)
# Additional include paths needed by kselftest.h
CFLAGS += -I../
@@ -2,21 +2,39 @@
#define _GNU_SOURCE
+#include <endian.h>
#include <errno.h>
#include <fcntl.h>
+#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
-#include <linux/if.h>
+#include <net/if.h>
+#include <netinet/ip.h>
+#include <sys/ioctl.h>
+#include <sys/socket.h>
+#include <linux/compiler.h>
+#include <linux/icmp.h>
+#include <linux/if_arp.h>
#include <linux/if_tun.h>
+#include <linux/ipv6.h>
#include <linux/netlink.h>
#include <linux/rtnetlink.h>
-#include <sys/ioctl.h>
-#include <sys/socket.h>
+#include <linux/sockios.h>
+#include <linux/tcp.h>
+#include <linux/udp.h>
+#include <linux/virtio_net.h>
#include "../kselftest_harness.h"
+#define TUN_HWADDR_SOURCE { 0x02, 0x00, 0x00, 0x00, 0x00, 0x00 }
+
+#define TUN_HWADDR_DEST { 0x02, 0x00, 0x00, 0x00, 0x00, 0x01 }
+
+#define TUN_IPADDR_SOURCE htonl((172 << 24) | (17 << 16) | 0)
+#define TUN_IPADDR_DEST htonl((172 << 24) | (17 << 16) | 1)
+
static int tun_attach(int fd, char *dev)
{
struct ifreq ifr;
@@ -39,7 +57,7 @@ static int tun_detach(int fd, char *dev)
return ioctl(fd, TUNSETQUEUE, (void *) &ifr);
}
-static int tun_alloc(char *dev)
+static int tun_alloc(char *dev, short flags)
{
struct ifreq ifr;
int fd, err;
@@ -52,7 +70,8 @@ static int tun_alloc(char *dev)
memset(&ifr, 0, sizeof(ifr));
strcpy(ifr.ifr_name, dev);
- ifr.ifr_flags = IFF_TAP | IFF_NAPI | IFF_MULTI_QUEUE;
+ ifr.ifr_flags = flags | IFF_TAP | IFF_NAPI | IFF_NO_PI |
+ IFF_MULTI_QUEUE;
err = ioctl(fd, TUNSETIFF, (void *) &ifr);
if (err < 0) {
@@ -64,6 +83,40 @@ static int tun_alloc(char *dev)
return fd;
}
+static bool tun_add_to_bridge(int local_fd, const char *name)
+{
+ struct ifreq ifreq = {
+ .ifr_name = "xbridge",
+ .ifr_ifindex = if_nametoindex(name)
+ };
+
+ if (!ifreq.ifr_ifindex) {
+ perror("if_nametoindex");
+ return false;
+ }
+
+ if (ioctl(local_fd, SIOCBRADDIF, &ifreq)) {
+ perror("SIOCBRADDIF");
+ return false;
+ }
+
+ return true;
+}
+
+static bool tun_set_flags(int local_fd, const char *name, short flags)
+{
+ struct ifreq ifreq = { .ifr_flags = flags };
+
+ strcpy(ifreq.ifr_name, name);
+
+ if (ioctl(local_fd, SIOCSIFFLAGS, &ifreq)) {
+ perror("SIOCSIFFLAGS");
+ return false;
+ }
+
+ return true;
+}
+
static int tun_delete(char *dev)
{
struct {
@@ -102,6 +155,153 @@ static int tun_delete(char *dev)
return ret;
}
+static uint32_t tun_sum(const void *buf, size_t len)
+{
+ const uint16_t *sbuf = buf;
+ uint32_t sum = 0;
+
+ while (len > 1) {
+ sum += *sbuf++;
+ len -= 2;
+ }
+
+ if (len)
+ sum += *(uint8_t *)sbuf;
+
+ return sum;
+}
+
+static uint16_t tun_build_ip_check(uint32_t sum)
+{
+ return ~((sum & 0xffff) + (sum >> 16));
+}
+
+static uint32_t tun_build_ip_pseudo_sum(const void *iphdr)
+{
+ uint16_t tot_len = ntohs(((struct iphdr *)iphdr)->tot_len);
+
+ return tun_sum((char *)iphdr + offsetof(struct iphdr, saddr), 8) +
+ htons(((struct iphdr *)iphdr)->protocol) +
+ htons(tot_len - sizeof(struct iphdr));
+}
+
+static uint32_t tun_build_ipv6_pseudo_sum(const void *ipv6hdr)
+{
+ return tun_sum((char *)ipv6hdr + offsetof(struct ipv6hdr, saddr), 32) +
+ ((struct ipv6hdr *)ipv6hdr)->payload_len +
+ htons(((struct ipv6hdr *)ipv6hdr)->nexthdr);
+}
+
+static void tun_build_ethhdr(struct ethhdr *ethhdr, uint16_t proto)
+{
+ *ethhdr = (struct ethhdr) {
+ .h_dest = TUN_HWADDR_DEST,
+ .h_source = TUN_HWADDR_SOURCE,
+ .h_proto = htons(proto)
+ };
+}
+
+static void tun_build_iphdr(void *dest, uint16_t len, uint8_t protocol)
+{
+ struct iphdr iphdr = {
+ .ihl = sizeof(iphdr) / 4,
+ .version = 4,
+ .tot_len = htons(sizeof(iphdr) + len),
+ .ttl = 255,
+ .protocol = protocol,
+ .saddr = TUN_IPADDR_SOURCE,
+ .daddr = TUN_IPADDR_DEST
+ };
+
+ iphdr.check = tun_build_ip_check(tun_sum(&iphdr, sizeof(iphdr)));
+ memcpy(dest, &iphdr, sizeof(iphdr));
+}
+
+static void tun_build_ipv6hdr(void *dest, uint16_t len, uint8_t protocol)
+{
+ struct ipv6hdr ipv6hdr = {
+ .version = 6,
+ .payload_len = htons(len),
+ .nexthdr = protocol,
+ .saddr = {
+ .s6_addr32 = {
+ htonl(0xffff0000), 0, 0, TUN_IPADDR_SOURCE
+ }
+ },
+ .daddr = {
+ .s6_addr32 = {
+ htonl(0xffff0000), 0, 0, TUN_IPADDR_DEST
+ }
+ },
+ };
+
+ memcpy(dest, &ipv6hdr, sizeof(ipv6hdr));
+}
+
+static void tun_build_tcphdr(void *dest, uint32_t sum)
+{
+ struct tcphdr tcphdr = {
+ .source = htons(9),
+ .dest = htons(9),
+ .fin = 1,
+ .doff = sizeof(tcphdr) / 4,
+ };
+ uint32_t tcp_sum = tun_sum(&tcphdr, sizeof(tcphdr));
+
+ tcphdr.check = tun_build_ip_check(sum + tcp_sum);
+ memcpy(dest, &tcphdr, sizeof(tcphdr));
+}
+
+static void tun_build_udphdr(void *dest, uint32_t sum)
+{
+ struct udphdr udphdr = {
+ .source = htons(9),
+ .dest = htons(9),
+ .len = htons(sizeof(udphdr)),
+ };
+ uint32_t udp_sum = tun_sum(&udphdr, sizeof(udphdr));
+
+ udphdr.check = tun_build_ip_check(sum + udp_sum);
+ memcpy(dest, &udphdr, sizeof(udphdr));
+}
+
+static bool tun_vnet_hash_check(int source_fd, const int *dest_fds,
+ const void *buffer, size_t len,
+ uint16_t report, uint32_t value)
+{
+ size_t read_len = sizeof(struct virtio_net_hdr_v1_hash) + len;
+ struct virtio_net_hdr_v1_hash *read_buffer;
+ int ret;
+
+ if (write(source_fd, buffer, len) != len) {
+ perror("write");
+ return false;
+ }
+
+ read_buffer = malloc(read_len);
+ if (!read_buffer) {
+ perror("malloc");
+ return false;
+ }
+
+ ret = read(dest_fds[value & 1], read_buffer, read_len);
+ if (ret != read_len) {
+ perror("read");
+ free(read_buffer);
+ return false;
+ }
+
+ if (read_buffer->hash_value != htole32(value) ||
+ read_buffer->hash_report != htole16(report) ||
+ memcmp(read_buffer + 1, buffer, len)) {
+ free(read_buffer);
+ return false;
+ }
+
+ free(read_buffer);
+ return true;
+}
+
FIXTURE(tun)
{
char ifname[IFNAMSIZ];
@@ -112,10 +312,10 @@ FIXTURE_SETUP(tun)
{
memset(self->ifname, 0, sizeof(self->ifname));
- self->fd = tun_alloc(self->ifname);
+ self->fd = tun_alloc(self->ifname, 0);
ASSERT_GE(self->fd, 0);
- self->fd2 = tun_alloc(self->ifname);
+ self->fd2 = tun_alloc(self->ifname, 0);
ASSERT_GE(self->fd2, 0);
}
@@ -159,4 +359,368 @@ TEST_F(tun, reattach_close_delete) {
EXPECT_EQ(tun_delete(self->ifname), 0);
}
+FIXTURE(tun_vnet_hash)
+{
+ int local_fd;
+ int source_fd;
+ int dest_fds[2];
+};
+
+FIXTURE_SETUP(tun_vnet_hash)
+{
+ static const struct {
+ struct tun_vnet_hash hdr;
+ uint16_t indirection_table[ARRAY_SIZE(self->dest_fds)];
+ uint8_t key[40];
+ } vnet_hash = {
+ .hdr = {
+ .flags = TUN_VNET_HASH_REPORT | TUN_VNET_HASH_RSS,
+ .types = VIRTIO_NET_RSS_HASH_TYPE_IPv4 |
+ VIRTIO_NET_RSS_HASH_TYPE_TCPv4 |
+ VIRTIO_NET_RSS_HASH_TYPE_UDPv4 |
+ VIRTIO_NET_RSS_HASH_TYPE_IPv6 |
+ VIRTIO_NET_RSS_HASH_TYPE_TCPv6 |
+ VIRTIO_NET_RSS_HASH_TYPE_UDPv6,
+ .indirection_table_mask = 1
+ },
+ .indirection_table = { 0, 1 },
+ .key = {
+ 0x6d, 0x5a, 0x56, 0xda, 0x25, 0x5b, 0x0e, 0xc2,
+ 0x41, 0x67, 0x25, 0x3d, 0x43, 0xa3, 0x8f, 0xb0,
+ 0xd0, 0xca, 0x2b, 0xcb, 0xae, 0x7b, 0x30, 0xb4,
+ 0x77, 0xcb, 0x2d, 0xa3, 0x80, 0x30, 0xf2, 0x0c,
+ 0x6a, 0x42, 0xb7, 0x3b, 0xbe, 0xac, 0x01, 0xfa
+ }
+ };
+
+ struct {
+ struct virtio_net_hdr_v1_hash vnet_hdr;
+ struct ethhdr ethhdr;
+ struct arphdr arphdr;
+ unsigned char sender_hwaddr[6];
+ uint32_t sender_ipaddr;
+ unsigned char target_hwaddr[6];
+ uint32_t target_ipaddr;
+ } __packed packet = {
+ .ethhdr = {
+ .h_source = TUN_HWADDR_SOURCE,
+ .h_dest = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff },
+ .h_proto = htons(ETH_P_ARP)
+ },
+ .arphdr = {
+ .ar_hrd = htons(ARPHRD_ETHER),
+ .ar_pro = htons(ETH_P_IP),
+ .ar_hln = ETH_ALEN,
+ .ar_pln = 4,
+ .ar_op = htons(ARPOP_REQUEST)
+ },
+ .sender_hwaddr = TUN_HWADDR_DEST,
+ .sender_ipaddr = TUN_IPADDR_DEST,
+ .target_ipaddr = TUN_IPADDR_DEST
+ };
+
+ char ifname[IFNAMSIZ];
+ int i;
+
+ self->local_fd = socket(AF_LOCAL, SOCK_STREAM, 0);
+ ASSERT_GE(self->local_fd, 0);
+
+ ASSERT_EQ(ioctl(self->local_fd, SIOCBRADDBR, "xbridge"), 0);
+ ASSERT_TRUE(tun_set_flags(self->local_fd, "xbridge", IFF_UP));
+
+ ifname[0] = 0;
+ self->source_fd = tun_alloc(ifname, 0);
+ ASSERT_GE(self->source_fd, 0);
+ ASSERT_TRUE(tun_add_to_bridge(self->local_fd, ifname));
+ ASSERT_TRUE(tun_set_flags(self->local_fd, ifname, IFF_UP));
+
+ ifname[0] = 0;
+ for (size_t i = 0; i < ARRAY_SIZE(self->dest_fds); i++) {
+ self->dest_fds[i] = tun_alloc(ifname, IFF_VNET_HDR);
+ ASSERT_GE(self->dest_fds[i], 0);
+ }
+
+ ASSERT_TRUE(tun_add_to_bridge(self->local_fd, ifname));
+ i = sizeof(struct virtio_net_hdr_v1_hash);
+ ASSERT_EQ(ioctl(self->dest_fds[0], TUNSETVNETHDRSZ, &i), 0);
+ i = 1;
+ ASSERT_EQ(ioctl(self->dest_fds[0], TUNSETVNETLE, &i), 0);
+ ASSERT_TRUE(tun_set_flags(self->local_fd, ifname, IFF_UP));
+ ASSERT_EQ(write(self->dest_fds[0], &packet, sizeof(packet)),
+ sizeof(packet));
+ ASSERT_EQ(ioctl(self->dest_fds[0], TUNSETVNETHASH, &vnet_hash), 0);
+}
+
+FIXTURE_TEARDOWN(tun_vnet_hash)
+{
+ ASSERT_TRUE(tun_set_flags(self->local_fd, "xbridge", 0));
+ EXPECT_EQ(ioctl(self->local_fd, SIOCBRDELBR, "xbridge"), 0);
+ EXPECT_EQ(close(self->source_fd), 0);
+
+ for (size_t i = 0; i < ARRAY_SIZE(self->dest_fds); i++)
+ EXPECT_EQ(close(self->dest_fds[i]), 0);
+
+ EXPECT_EQ(close(self->local_fd), 0);
+}
+
+TEST_F(tun_vnet_hash, ipv4)
+{
+ struct {
+ struct ethhdr ethhdr;
+ struct iphdr iphdr;
+ } __packed packet;
+
+ tun_build_ethhdr(&packet.ethhdr, ETH_P_IP);
+ tun_build_iphdr(&packet.iphdr, 0, 253);
+
+ EXPECT_TRUE(tun_vnet_hash_check(self->source_fd, self->dest_fds,
+ &packet, sizeof(packet),
+ VIRTIO_NET_HASH_REPORT_IPv4,
+ 0x9246d590));
+}
+
+TEST_F(tun_vnet_hash, tcpv4)
+{
+ struct {
+ struct ethhdr ethhdr;
+ struct iphdr iphdr;
+ struct tcphdr tcphdr;
+ } __packed packet;
+
+ tun_build_ethhdr(&packet.ethhdr, ETH_P_IP);
+ tun_build_iphdr(&packet.iphdr, sizeof(struct tcphdr), IPPROTO_TCP);
+
+ tun_build_tcphdr(&packet.tcphdr,
+ tun_build_ip_pseudo_sum(&packet.iphdr));
+
+ EXPECT_TRUE(tun_vnet_hash_check(self->source_fd, self->dest_fds,
+ &packet, sizeof(packet),
+ VIRTIO_NET_HASH_REPORT_TCPv4,
+ 0xfad3f31a));
+}
+
+TEST_F(tun_vnet_hash, udpv4)
+{
+ struct {
+ struct ethhdr ethhdr;
+ struct iphdr iphdr;
+ struct udphdr udphdr;
+ } __packed packet;
+
+ tun_build_ethhdr(&packet.ethhdr, ETH_P_IP);
+ tun_build_iphdr(&packet.iphdr, sizeof(struct udphdr), IPPROTO_UDP);
+
+ tun_build_udphdr(&packet.udphdr,
+ tun_build_ip_pseudo_sum(&packet.iphdr));
+
+ EXPECT_TRUE(tun_vnet_hash_check(self->source_fd, self->dest_fds,
+ &packet, sizeof(packet),
+ VIRTIO_NET_HASH_REPORT_UDPv4,
+ 0xfad3f31a));
+}
+
+TEST_F(tun_vnet_hash, ipv6)
+{
+ struct {
+ struct ethhdr ethhdr;
+ struct ipv6hdr ipv6hdr;
+ } __packed packet;
+
+ tun_build_ethhdr(&packet.ethhdr, ETH_P_IPV6);
+ tun_build_ipv6hdr(&packet.ipv6hdr, 0, 253);
+
+ EXPECT_TRUE(tun_vnet_hash_check(self->source_fd, self->dest_fds,
+ &packet, sizeof(packet),
+ VIRTIO_NET_HASH_REPORT_IPv6,
+ 0x6b7835b3));
+}
+
+TEST_F(tun_vnet_hash, tcpv6)
+{
+ struct {
+ struct ethhdr ethhdr;
+ struct ipv6hdr ipv6hdr;
+ struct tcphdr tcphdr;
+ } __packed packet;
+
+ tun_build_ethhdr(&packet.ethhdr, ETH_P_IPV6);
+ tun_build_ipv6hdr(&packet.ipv6hdr, sizeof(struct tcphdr), IPPROTO_TCP);
+
+ tun_build_tcphdr(&packet.tcphdr,
+ tun_build_ipv6_pseudo_sum(&packet.ipv6hdr));
+
+ EXPECT_TRUE(tun_vnet_hash_check(self->source_fd, self->dest_fds,
+ &packet, sizeof(packet),
+ VIRTIO_NET_HASH_REPORT_TCPv6,
+ 0x6c6717));
+}
+
+TEST_F(tun_vnet_hash, udpv6)
+{
+ struct {
+ struct ethhdr ethhdr;
+ struct ipv6hdr ipv6hdr;
+ struct udphdr udphdr;
+ } __packed packet;
+
+ tun_build_ethhdr(&packet.ethhdr, ETH_P_IPV6);
+ tun_build_ipv6hdr(&packet.ipv6hdr, sizeof(struct udphdr), IPPROTO_UDP);
+
+ tun_build_udphdr(&packet.udphdr,
+ tun_build_ipv6_pseudo_sum(&packet.ipv6hdr));
+
+ EXPECT_TRUE(tun_vnet_hash_check(self->source_fd, self->dest_fds,
+ &packet, sizeof(packet),
+ VIRTIO_NET_HASH_REPORT_UDPv6,
+ 0x6c6717));
+}
+
+FIXTURE(tun_vnet_hash_config)
+{
+ int fd;
+};
+
+FIXTURE_SETUP(tun_vnet_hash_config)
+{
+ char ifname[IFNAMSIZ];
+
+ ifname[0] = 0;
+ self->fd = tun_alloc(ifname, 0);
+ ASSERT_GE(self->fd, 0);
+}
+
+FIXTURE_TEARDOWN(tun_vnet_hash_config)
+{
+ EXPECT_EQ(close(self->fd), 0);
+}
+
+TEST_F(tun_vnet_hash_config, cap)
+{
+ struct tun_vnet_hash_cap cap;
+
+ ASSERT_EQ(ioctl(self->fd, TUNGETVNETHASHCAP, &cap), 0);
+ EXPECT_EQ(cap.max_indirection_table_length, 128);
+ EXPECT_EQ(cap.types,
+ VIRTIO_NET_RSS_HASH_TYPE_IPv4 |
+ VIRTIO_NET_RSS_HASH_TYPE_TCPv4 |
+ VIRTIO_NET_RSS_HASH_TYPE_UDPv4 |
+ VIRTIO_NET_RSS_HASH_TYPE_IPv6 |
+ VIRTIO_NET_RSS_HASH_TYPE_TCPv6 |
+ VIRTIO_NET_RSS_HASH_TYPE_UDPv6);
+}
+
+TEST_F(tun_vnet_hash_config, insufficient_hdr_sz)
+{
+ static const struct tun_vnet_hash vnet_hash = {
+ .flags = TUN_VNET_HASH_REPORT
+ };
+ int i;
+
+ i = 1;
+ ASSERT_EQ(ioctl(self->fd, TUNSETVNETLE, &i), 0);
+
+ ASSERT_EQ(ioctl(self->fd, TUNSETVNETHASH, &vnet_hash), -1);
+ EXPECT_EQ(errno, EINVAL);
+}
+
+TEST_F(tun_vnet_hash_config, shrink_hdr_sz)
+{
+ static const struct tun_vnet_hash vnet_hash = {
+ .flags = TUN_VNET_HASH_REPORT
+ };
+ int i;
+
+ i = sizeof(struct virtio_net_hdr_v1_hash);
+ ASSERT_EQ(ioctl(self->fd, TUNSETVNETHDRSZ, &i), 0);
+
+ i = 1;
+ ASSERT_EQ(ioctl(self->fd, TUNSETVNETLE, &i), 0);
+
+ ASSERT_EQ(ioctl(self->fd, TUNSETVNETHASH, &vnet_hash), 0);
+
+ i = sizeof(struct virtio_net_hdr);
+ ASSERT_EQ(ioctl(self->fd, TUNSETVNETHDRSZ, &i), -1);
+ EXPECT_EQ(errno, EINVAL);
+}
+
+TEST_F(tun_vnet_hash_config, too_big_indirection_table)
+{
+ static const struct tun_vnet_hash vnet_hash = {
+ .flags = TUN_VNET_HASH_REPORT,
+ .indirection_table_mask = 255
+ };
+ int i;
+
+ i = sizeof(struct virtio_net_hdr_v1_hash);
+ ASSERT_EQ(ioctl(self->fd, TUNSETVNETHDRSZ, &i), 0);
+
+ i = 1;
+ ASSERT_EQ(ioctl(self->fd, TUNSETVNETLE, &i), 0);
+
+ ASSERT_EQ(ioctl(self->fd, TUNSETVNETHASH, &vnet_hash), -1);
+ EXPECT_EQ(errno, EINVAL);
+}
+
+TEST_F(tun_vnet_hash_config, set_be_early)
+{
+ static const struct tun_vnet_hash vnet_hash = {
+ .flags = TUN_VNET_HASH_REPORT
+ };
+ int i;
+
+ i = 1;
+ if (ioctl(self->fd, TUNSETVNETBE, &i))
+ return;
+
+ i = sizeof(struct virtio_net_hdr_v1_hash);
+ ASSERT_EQ(ioctl(self->fd, TUNSETVNETHDRSZ, &i), 0);
+
+ ASSERT_EQ(ioctl(self->fd, TUNSETVNETHASH, &vnet_hash), -1);
+ EXPECT_EQ(errno, EINVAL);
+}
+
+TEST_F(tun_vnet_hash_config, set_be_later)
+{
+ static const struct tun_vnet_hash vnet_hash = {
+ .flags = TUN_VNET_HASH_REPORT
+ };
+ int i;
+
+ i = sizeof(struct virtio_net_hdr_v1_hash);
+ ASSERT_EQ(ioctl(self->fd, TUNSETVNETHDRSZ, &i), 0);
+
+ if (ioctl(self->fd, TUNSETVNETHASH, &vnet_hash))
+ return;
+
+ i = 1;
+ ASSERT_EQ(ioctl(self->fd, TUNSETVNETBE, &i), -1);
+ EXPECT_EQ(errno, EINVAL);
+}
+
+TEST_F(tun_vnet_hash_config, unset_le_later)
+{
+ static const struct tun_vnet_hash vnet_hash = {
+ .flags = TUN_VNET_HASH_REPORT
+ };
+ int i;
+
+ i = sizeof(struct virtio_net_hdr_v1_hash);
+ ASSERT_EQ(ioctl(self->fd, TUNSETVNETHDRSZ, &i), 0);
+
+ i = 1;
+ ioctl(self->fd, TUNSETVNETBE, &i);
+
+ if (!ioctl(self->fd, TUNSETVNETHASH, &vnet_hash))
+ return;
+
+ i = 1;
+ ASSERT_EQ(ioctl(self->fd, TUNSETVNETLE, &i), 0);
+
+ ASSERT_EQ(ioctl(self->fd, TUNSETVNETHASH, &vnet_hash), 0);
+
+ i = 0;
+ ASSERT_EQ(ioctl(self->fd, TUNSETVNETLE, &i), -1);
+ EXPECT_EQ(errno, EINVAL);
+}
+
TEST_HARNESS_MAIN
The added tests confirm tun can perform RSS and hash reporting, and reject invalid configurations for them. Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com> --- tools/testing/selftests/net/Makefile | 2 +- tools/testing/selftests/net/tun.c | 578 ++++++++++++++++++++++++++- 2 files changed, 572 insertions(+), 8 deletions(-)