platform/minimal-net: Better, more seamless support for OS X.

This patch enables automatic route setup and cleanup when
starting and stopping the minimal-net target on OS X.

Both IPv4 and IPv6 are supported.

Using the minimal-net target on OS X was absolute hell
before I came up with this patch. Now it is painless.

cpu/native/Makefile.native

@@ -18,10 +18,15 @@ CFLAGSWERROR=-Werror -pedantic -std=c99 -Werror
 endif
 CFLAGSNO = -Wall -g -I/usr/local/include $(CFLAGSWERROR)
 CFLAGS  += $(CFLAGSNO) -O
-ifeq ($(HOST_OS),Linux)
+
-  LDFLAGS  += -Wl,-Map=contiki-$(TARGET).map,-export-dynamic
+ifeq ($(shell uname),Darwin)
+AROPTS = -r
+LDFLAGS += -Wl,-flat_namespace
+CFLAGS += -DHAVE_SNPRINTF=1 -U__ASSERT_USE_STDERR
 else
-  LDFLAGS  += -Wl
+ifeq ($(HOST_OS),Linux)
+LDFLAGS  = -Wl,-Map=contiki-$(TARGET).map,-export-dynamic
+endif
 endif
 
 ### Compilation rules

cpu/native/net/tapdev.c

@@ -81,7 +81,7 @@ static void
 remove_route(void)
 {
   char buf[1024];
-  snprintf(buf, sizeof(buf), "route delete -net 172.16.0.0");
+  snprintf(buf, sizeof(buf), "route delete -net 172.18.0.0");
   system(buf);
   printf("%s\n", buf);
 
@@ -110,15 +110,15 @@ tapdev_init(void)
   }
 #endif /* Linux */
 
-  snprintf(buf, sizeof(buf), "ifconfig tap0 inet 192.168.1.1");
+  snprintf(buf, sizeof(buf), "ifconfig tap0 inet 172.18.0.1/16");
   system(buf);
   printf("%s\n", buf);
 #ifdef linux
   /* route add for linux */
-  snprintf(buf, sizeof(buf), "route add -net 172.16.0.0/16 gw 192.168.1.2");
+  snprintf(buf, sizeof(buf), "route add -net 172.18.0.0/16 dev tap0");
 #else /* linux */
   /* route add for freebsd */
-  snprintf(buf, sizeof(buf), "route add -net 172.16.0.0/16 192.168.1.2");
+  snprintf(buf, sizeof(buf), "route add -net 172.18.0.0/16 -iface tap0");
 #endif /* linux */
   
   system(buf);

cpu/native/net/tapdev6.c

@@ -56,6 +56,17 @@
 #define DEVTAP "/dev/tap0"
 #endif /* linux */
 
+#ifdef __APPLE__
+#include <net/if.h>
+#include <netinet/in.h>
+#include <netinet6/in6_var.h>
+#include <netinet6/nd6.h> // ND6_INFINITE_LIFETIME
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/errno.h>
+#include <net/if_dl.h> // struct sockaddr_dl
+#include <net/route.h> // AF_ROUTE things
+#endif
 
 #include "tapdev6.h"
 #include "contiki-net.h"
@@ -66,7 +77,7 @@
 static int drop = 0;
 #endif
 
-static int fd;
+static int fd = -1;
 
 static unsigned long lasttime;
 
@@ -123,6 +134,159 @@ tapdev_poll(void)
   return ret;
 }
 /*---------------------------------------------------------------------------*/
+#if defined(__APPLE__)
+static int reqfd = -1, sfd = -1, interface_index;
+
+static void
+tapdev_init_darwin_routes(void)
+{
+  struct stat st;
+
+  if(-1 == fstat(fd, &st)) {
+    perror("tapdev: fstat failed.");
+    exit(EXIT_FAILURE);
+  }
+
+  /************* Add address *************/
+
+  struct in6_aliasreq addreq6 = { };
+  reqfd = socket(AF_INET6, SOCK_DGRAM, 0);
+
+  if(-1 == fcntl(reqfd, F_SETFD, FD_CLOEXEC)) {
+    perror("tapdev: fcntl failed.");
+    exit(EXIT_FAILURE);
+  }
+
+  devname_r(st.st_rdev, S_IFCHR, addreq6.ifra_name,
+            sizeof(addreq6.ifra_name));
+
+  addreq6.ifra_addr.sin6_family = AF_INET6;
+  addreq6.ifra_addr.sin6_len = sizeof(addreq6.ifra_addr);
+  addreq6.ifra_addr.sin6_addr.__u6_addr.__u6_addr16[0] = UIP_HTONS(0xAAAA);
+  addreq6.ifra_addr.sin6_addr.__u6_addr.__u6_addr16[7] = UIP_HTONS(0x0001);
+
+  addreq6.ifra_prefixmask.sin6_family = AF_INET6;
+  addreq6.ifra_prefixmask.sin6_len = sizeof(addreq6.ifra_prefixmask);
+  addreq6.ifra_prefixmask.sin6_addr.__u6_addr.__u6_addr16[0] =
+    UIP_HTONS(0xFFFF);
+  addreq6.ifra_prefixmask.sin6_addr.__u6_addr.__u6_addr16[1] =
+    UIP_HTONS(0xFFFF);
+  addreq6.ifra_prefixmask.sin6_addr.__u6_addr.__u6_addr16[2] =
+    UIP_HTONS(0xFFFF);
+  addreq6.ifra_prefixmask.sin6_addr.__u6_addr.__u6_addr16[3] =
+    UIP_HTONS(0xFFFF);
+
+  addreq6.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME;
+  addreq6.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME;
+  addreq6.ifra_lifetime.ia6t_expire = ND6_INFINITE_LIFETIME;
+  addreq6.ifra_lifetime.ia6t_preferred = ND6_INFINITE_LIFETIME;
+
+  if(-1 == ioctl(reqfd, SIOCAIFADDR_IN6, &addreq6)) {
+    perror("tapdev: Uable to add address, call to ioctl failed.");
+    exit(EXIT_FAILURE);
+  }
+
+  /************* Add route *************/
+
+  int s = socket(AF_ROUTE, SOCK_RAW, AF_INET6);
+
+  if(s == -1) {
+    perror("tapdev: Unable to add route, call to socket() failed.");
+
+    // Failing to add the route is not fatal, so just return.
+    return;
+  }
+
+  sfd = s;
+  interface_index = if_nametoindex(devname(st.st_rdev, S_IFCHR));
+
+  PRINTF("tapdev: if_nametoindex(devname(st.st_rdev, S_IFCHR)) = %d\n",
+         interface_index);
+  PRINTF("tapdev: devname(st.st_rdev, S_IFCHR) = %s\n",
+         devname(st.st_rdev, S_IFCHR));
+
+  struct {
+    struct rt_msghdr hdr;
+    struct sockaddr_in6 dst;
+    struct sockaddr_dl gw;
+    struct sockaddr_in6 mask;
+  } msg = {};
+
+  msg.hdr.rtm_msglen = sizeof(msg);
+  msg.hdr.rtm_version = RTM_VERSION;
+  msg.hdr.rtm_type = RTM_ADD;
+  msg.hdr.rtm_index = interface_index;
+  msg.hdr.rtm_flags = RTF_UP | RTF_STATIC;
+  msg.hdr.rtm_addrs = RTA_DST | RTA_GATEWAY | RTA_NETMASK;
+  msg.hdr.rtm_pid = getpid();
+  msg.hdr.rtm_seq = 0;
+
+  msg.dst.sin6_family = AF_INET6;
+  msg.dst.sin6_len = sizeof(msg.dst);
+  msg.dst.sin6_addr.__u6_addr.__u6_addr16[0] = UIP_HTONS(0xAAAA);
+
+  msg.gw.sdl_family = AF_LINK;
+  msg.gw.sdl_len = sizeof(msg.gw);
+  msg.gw.sdl_index = interface_index;
+
+  msg.mask.sin6_family = AF_INET6;
+  msg.mask.sin6_len = sizeof(msg.mask);
+  msg.mask.sin6_addr.__u6_addr.__u6_addr16[0] = UIP_HTONS(0xFFFF);
+  msg.mask.sin6_addr.__u6_addr.__u6_addr16[1] = UIP_HTONS(0xFFFF);
+  msg.mask.sin6_addr.__u6_addr.__u6_addr16[2] = UIP_HTONS(0xFFFF);
+  msg.mask.sin6_addr.__u6_addr.__u6_addr16[3] = UIP_HTONS(0xFFFF);
+
+  if(-1 == write(s, &msg, sizeof(msg))) {
+    perror("tapdev: Unable to add route, call to write() failed.");
+
+    // Failing to add the route is not fatal, so just return.
+    return;
+  }
+}
+/*---------------------------------------------------------------------------*/
+static void
+tapdev_cleanup_darwin_routes(void)
+{
+  struct {
+    struct rt_msghdr hdr;
+    struct sockaddr_in6 dst;
+    struct sockaddr_dl gw;
+    struct sockaddr_in6 mask;
+  } msg = {};
+
+  msg.hdr.rtm_msglen = sizeof(msg);
+  msg.hdr.rtm_version = RTM_VERSION;
+  msg.hdr.rtm_type = RTM_DELETE;
+  msg.hdr.rtm_index = interface_index;
+  msg.hdr.rtm_flags = RTF_UP | RTF_STATIC;
+  msg.hdr.rtm_addrs = RTA_DST | RTA_GATEWAY | RTA_NETMASK;
+  msg.hdr.rtm_pid = getpid();
+  msg.hdr.rtm_seq = 0;
+
+  msg.dst.sin6_family = AF_INET6;
+  msg.dst.sin6_len = sizeof(msg.dst);
+  msg.dst.sin6_addr.__u6_addr.__u6_addr16[0] = UIP_HTONS(0xAAAA);
+
+  msg.gw.sdl_family = AF_LINK;
+  msg.gw.sdl_len = sizeof(msg.gw);
+  msg.gw.sdl_index = interface_index;
+
+  msg.mask.sin6_family = AF_INET6;
+  msg.mask.sin6_len = sizeof(msg.mask);
+  msg.mask.sin6_addr.__u6_addr.__u6_addr16[0] = UIP_HTONS(0xFFFF);
+  msg.mask.sin6_addr.__u6_addr.__u6_addr16[1] = UIP_HTONS(0xFFFF);
+  msg.mask.sin6_addr.__u6_addr.__u6_addr16[2] = UIP_HTONS(0xFFFF);
+  msg.mask.sin6_addr.__u6_addr.__u6_addr16[3] = UIP_HTONS(0xFFFF);
+  if(-1 == write(sfd, &msg, sizeof(msg))) {
+    perror("tapdev: Unable to delete route");
+    exit(EXIT_FAILURE);
+  }
+
+  close(reqfd);
+  close(sfd);
+}
+#endif // defined(__APPLE__)
+/*---------------------------------------------------------------------------*/
 void
 tapdev_init(void)
 {
@@ -146,6 +310,10 @@ tapdev_init(void)
   }
 #endif /* Linux */
 
+#ifdef __APPLE__
+  tapdev_init_darwin_routes();
+#endif
+
   /* Linux (ubuntu)
      snprintf(buf, sizeof(buf), "ip link set tap0 up");
      system(buf);
@@ -236,5 +404,12 @@ tapdev_do_send(void)
 void
 tapdev_exit(void)
 {
+  PRINTF("tapdev: Closing...\n");
+
+#ifdef __APPLE__
+  tapdev_cleanup_darwin_routes();
+#endif
+
+  close(fd);
 }
 /*---------------------------------------------------------------------------*/

platform/minimal-net/contiki-main.c

@@ -236,21 +236,21 @@ main(void)
 
     uip_gethostaddr(&addr);
     if(addr.u8[0] == 0) {
-      uip_ipaddr(&addr, 10,1,1,1);
+      uip_ipaddr(&addr, 172,18,0,2);
     }
     printf("IP Address:  %d.%d.%d.%d\n", uip_ipaddr_to_quad(&addr));
     uip_sethostaddr(&addr);
     
     uip_getnetmask(&addr);
     if(addr.u8[0] == 0) {
-      uip_ipaddr(&addr, 255,0,0,0);
+      uip_ipaddr(&addr, 255,255,0,0);
       uip_setnetmask(&addr);
     }
     printf("Subnet Mask: %d.%d.%d.%d\n", uip_ipaddr_to_quad(&addr));
     
     uip_getdraddr(&addr);
     if(addr.u8[0] == 0) {
-      uip_ipaddr(&addr, 10,1,1,100);
+      uip_ipaddr(&addr, 172,18,0,1);
       uip_setdraddr(&addr);
     }
     printf("Def. Router: %d.%d.%d.%d\n", uip_ipaddr_to_quad(&addr));