Merge pull request torvalds#275 from libos-nuse/feature-dhclient

lkl: add dhcp client option

Documentation/lkl.txt

@@ -165,6 +165,12 @@ are the list of those variable for your environment.
 ```
     $ LKL_HIJACK_NET_IP=198.51.100.5 lkl-hijack.sh ip address show
 ```
+
+  Additionally, DHCP is experimentally available with the following syntax.
+```
+    $ LKL_HIJACK_NET_IP=dhcp LKL_HIJACK_NET_IFTYPE=tap LKL_HIJACK_NET_IFPARAMS=tap0 lkl-hijack.sh ip address show
+```
+
 * LKL_HIJACK_NET_NETMASK_LEN
 
   the network mask length of the interface specified by LKL_HIJACK_NET_TAP.

arch/lkl/Kconfig

@@ -21,6 +21,8 @@ config LKL
        select 64BIT if OUTPUT_FORMAT = "elf64-x86-64"
        select HAVE_UNDERSCORE_SYMBOL_PREFIX if OUTPUT_FORMAT = "pe-i386"
        select 64BIT if OUTPUT_FORMAT = "elf64-x86-64-freebsd"
+       select IP_PNP
+       select IP_PNP_DHCP
 
 config OUTPUTFORMAT
        string

tools/lkl/lib/hijack/init.c

@@ -218,6 +218,8 @@ hijack_init(void)
 	cpu_set_t ori_cpu;
 	char *offload1 = getenv("LKL_HIJACK_OFFLOAD");
 	int offload = 0;
+	/* with dhcp client by default */
+	char *boot_cmdline = "ip=dhcp";
 
 	memset(&nd_args, 0, sizeof(struct lkl_netdev_args));
 	if (!debug) {
@@ -323,7 +325,11 @@ hijack_init(void)
 	if (single_cpu_mode == 1)
 		PinToFirstCpu(&ori_cpu);
 
-	ret = lkl_start_kernel(&lkl_host_ops, 64 * 1024 * 1024UL, "");
+	/* clear cmdline if non-dhcp case */
+	if ((ip && strcmp(ip, "dhcp")) || (nd_id == -1))
+		boot_cmdline = "";
+
+	ret = lkl_start_kernel(&lkl_host_ops, 64 * 1024 * 1024UL, boot_cmdline);
 	if (ret) {
 		fprintf(stderr, "can't start kernel: %s\n", lkl_strerror(ret));
 		return;

tools/lkl/tests/net-test.c

@@ -97,7 +97,9 @@ static int test_icmp(char *str, int len)
 
 	iph = (struct iphdr *)buf;
 	icmp = (struct icmphdr *)(buf + iph->ihl * 4);
-	if (icmp->type != ICMP_ECHOREPLY || icmp->code != 0) {
+	/* DHCP server may issue an ICMP echo request to a dhcp client */
+	if ((icmp->type != ICMP_ECHOREPLY || icmp->code != 0) &&
+	    (icmp->type != ICMP_ECHO)) {
 		snprintf(str, len, "no ICMP echo reply (type=%d, code=%d)",
 			 icmp->type, icmp->code);
 		return TEST_FAILURE;
@@ -114,17 +116,19 @@ static int test_net_init(int argc, char **argv)
 	char *debug = getenv("LKL_DEBUG");
 	int ret, nd_id = -1, nd_ifindex = -1;
 	struct lkl_netdev *nd = NULL;
+	/* with dhcp client by default */
+	char boot_cmdline[256] = "\0";
 
-	if (argc < 6) {
-		printf("usage %s <iftype: tap|dpdk|raw> <ifname> <v4addr> <v4mask> <dstaddr> [gateway]\n", argv[0]);
+	if (argc < 3) {
+		printf("usage %s <iftype: tap|dpdk|raw> <ifname> <dstaddr> <v4addr>|dhcp <v4mask> [gateway]\n", argv[0]);
 		exit(0);
 	}
 
 	iftype = argv[1];
 	ifname = argv[2];
-	ip = argv[3];
-	netmask_len = argv[4];
-	dst = argv[5];
+	dst = argv[3];
+	ip = argv[4];
+	netmask_len = argv[5];
 
 	if (argc == 7)
 		gateway = argv[6];
@@ -156,7 +160,10 @@ static int test_net_init(int argc, char **argv)
 		lkl_host_ops.print = NULL;
 
 
-	ret = lkl_start_kernel(&lkl_host_ops, 64 * 1024 * 1024, "");
+	if (ip && !strcmp(ip, "dhcp"))
+		snprintf(boot_cmdline, sizeof(boot_cmdline), "ip=dhcp");
+
+	ret = lkl_start_kernel(&lkl_host_ops, 64 * 1024 * 1024, boot_cmdline);
 	if (ret) {
 		fprintf(stderr, "can't start kernel: %s\n", lkl_strerror(ret));
 		return -1;

tools/lkl/tests/net.sh

@@ -2,8 +2,12 @@
 
 IFNAME=`ip route |grep default | awk '{print $5}'`
 GW=`ip route |grep default | awk '{print $3}'`
-IPADDR=`echo $GW | sed -r "s/([0-9]+\.[0-9]+\.[0-9]+\.)([0-9]+)$/\1\`expr \2 + 10\`/"`
+HOST_IPADDR=`ip rou |grep ${IFNAME} | grep "scope link" | awk '{print $1}' | sed "s/\(.*\)\/.*/\1/"`
 PLEN=`ip rou |grep ${IFNAME} | grep "scope link" | awk '{print $1}' | sed "s/.*\/\(.*\)/\1/"`
+IPADDR=`echo ${HOST_IPADDR}|awk -F. '{printf ("%d.%d.%d.%d\n",$1,$2,$3,$4+10)}'`
+
+script_dir=$(cd $(dirname ${BASH_SOURCE:-$0}); pwd)
+cd ${script_dir}
 
 # And make sure we clean up when we're done
 function clear_work_dir {
@@ -22,7 +26,7 @@ if [ -c /dev/net/tun ]; then
     sudo ip link set dev lkl_ptt1 up
     sudo ip addr add dev lkl_ptt1 192.168.14.1/24
 
-    ./net-test tap lkl_ptt1 192.168.14.2 24 192.168.14.1
+    ./net-test tap lkl_ptt1 192.168.14.1 192.168.14.2 24
 
     sudo ip link set dev lkl_ptt1 down
     sudo ip tuntap del dev lkl_ptt1 mode tap
@@ -33,7 +37,11 @@ echo "== RAW socket (LKL net) tests =="
 if [ -n "`printenv CONFIG_AUTO_LKL_POSIX_HOST`" ] ; then
     sudo ip link set dev ${IFNAME} promisc on
     # this won't work if IFNAME is wifi since it rewrites the src macaddr
-    sudo ./net-test raw ${IFNAME} ${IPADDR} ${PLEN} 8.8.8.8 ${GW}
+    sudo ./net-test raw ${IFNAME} 8.8.8.8 ${IPADDR} ${PLEN} ${GW}
+
+    # DHCP test
+    echo "  == DHCP with RAW socket test =="
+    sudo ./net-test raw ${IFNAME} 8.8.8.8 dhcp
     sudo ip link set dev ${IFNAME} promisc off
 fi
 
@@ -44,13 +52,13 @@ if ls /dev/tap* > /dev/null 2>&1 ; then
     sudo ip link set dev lkl_vtap0 up
     sudo chown ${USER} `ls /dev/tap*`
 
-    ./net-test macvtap `ls /dev/tap*` ${IPADDR} ${PLEN} 8.8.8.8 ${GW}
+    ./net-test macvtap `ls /dev/tap*` 8.8.8.8 ${IPADDR} ${PLEN} ${GW}
 fi
 
 # we disabled this DPDK test because it's unlikely possible to describe
 # a generic set of commands for all environments to test with DPDK.  users
 # may customize those test commands for your host.
 if false ; then
     echo "== DPDK (LKL net) tests =="
-    sudo ./net-test dpdk dpdk0 192.168.15.2 24 192.168.15.1
+    sudo ./net-test dpdk dpdk0 192.168.15.1 192.168.15.2 24
 fi