commit f0fac8631a58ee6f12755e35f0476bef3f9bbb97
author Lorenzo Colitti <lorenzo@google.com> Fri Jan 11 18:10:11 2019 +0900
committer Lorenzo Colitti <lorenzo@google.com> Tue Jan 15 13:33:36 2019 +0900
tree 2c211b29071463e15af4273b0d061f3b14d080e3
parent 33351930039785304a283b072251a48cfae30a35

Allow passing in the IPv4 and IPv6 addresses on the command line.

This allows the address to be determined by netd and passed in,
which makes it possible for the rest of the OS to know what the
clatd IPv6 address is.

Bug: 65674744
Test: atest clatd_test
Test: IPv4 on IPv6-only networks continues to work
Test: clatd continues to avoid existing IPv4 addresses in 192.0.0.0/29
Test: passing NAT64 prefix, IPv4/IPv6 addresses on command line works
Change-Id: I8519c2f01b44022ef036c80aa0df32cd76003055

main.c

diff --git a/main.c b/main.c
index 11c51a5..54d12d1 100644
--- a/main.c
+++ b/main.c
@@ -42,6 +42,8 @@
   printf("android-clat arguments:\n");
   printf("-i [uplink interface]\n");
   printf("-p [plat prefix]\n");
+  printf("-4 [IPv4 address]\n");
+  printf("-6 [IPv6 address]\n");
   printf("-n [NetId]\n");
   printf("-m [socket mark]\n");
 }
@@ -53,11 +55,12 @@
   struct tun_data tunnel;
   int opt;
   char *uplink_interface = NULL, *plat_prefix = NULL, *net_id_str = NULL, *mark_str = NULL;
+  char *v4_addr = NULL, *v6_addr = NULL;
   unsigned net_id = NETID_UNSET;
   uint32_t mark   = MARK_UNSET;
   unsigned len;
 
-  while ((opt = getopt(argc, argv, "i:p:n:m:h")) != -1) {
+  while ((opt = getopt(argc, argv, "i:p:4:6:n:m:h")) != -1) {
     switch (opt) {
       case 'i':
         uplink_interface = optarg;
@@ -65,6 +68,12 @@
       case 'p':
         plat_prefix = optarg;
         break;
+      case '4':
+        v4_addr = optarg;
+        break;
+      case '6':
+        v6_addr = optarg;
+        break;
       case 'n':
         net_id_str = optarg;
         break;
@@ -101,8 +110,10 @@
     exit(1);
   }
 
-  logmsg(ANDROID_LOG_INFO, "Starting clat version %s on %s netid=%s mark=%s", CLATD_VERSION,
-         uplink_interface, net_id_str ? net_id_str : "(none)", mark_str ? mark_str : "(none)");
+  logmsg(ANDROID_LOG_INFO, "Starting clat version %s on %s netid=%s mark=%s plat=%s v4=%s v6=%s",
+         CLATD_VERSION, uplink_interface, net_id_str ? net_id_str : "(none)",
+         mark_str ? mark_str : "(none)", plat_prefix ? plat_prefix : "(none)",
+         v4_addr ? v4_addr : "(none)", v6_addr ? v6_addr : "(none)");
 
   // run under a regular user but keep needed capabilities
   drop_root_but_keep_caps();
@@ -125,7 +136,7 @@
   // following line causes XLAT failure in permissive mode.
   unsetenv("ANDROID_DNS_MODE");
 
-  configure_interface(uplink_interface, plat_prefix, &tunnel, net_id);
+  configure_interface(uplink_interface, plat_prefix, v4_addr, v6_addr, &tunnel, net_id);
 
   // Drop all remaining capabilities.
   set_capability(0);