tap_v2: multiple improvements

 - add support for assigning tap interface to the bridge
 - add support for assigning tap interface host side ip4 and ip6 address
 - host namespace can be specified as PID (pid:12345) or full path to file
 - automatically bring linux interface up

Change-Id: I1cf7c3cad9a740e430cc1b9c2bb0aad0ba4cc8d8
Signed-off-by: Damjan Marion <damarion@cisco.com>

1 files changed, 145 insertions, 41 deletions

diff --git a/src/vnet/devices/netlink.c b/src/vnet/devices/netlink.c
index b05daf2674a..b3330dd89b9 100644
--- a/src/vnet/devices/netlink.c
+++ b/src/vnet/devices/netlink.c
@@ -31,22 +31,51 @@
 #include <vlib/vlib.h>
 #include <vlib/unix/unix.h>
 
-clib_error_t *
-vnet_netlink_set_if_attr (int ifindex, unsigned short rta_type, void *data,
-			  int data_len)
+typedef struct
+{
+  u8 *data;
+} vnet_netlink_msg_t;
+
+void
+vnet_netlink_msg_init (vnet_netlink_msg_t * m, u16 type, u16 flags,
+		       void *msg_data, int msg_len)
+{
+  struct nlmsghdr *nh;
+  u8 *p;
+  int len = NLMSG_LENGTH (msg_len);
+  memset (m, 0, sizeof (vnet_netlink_msg_t));
+  vec_add2 (m->data, p, len);
+  ASSERT (m->data == p);
+
+  nh = (struct nlmsghdr *) p;
+  nh->nlmsg_flags = flags;
+  nh->nlmsg_type = type;
+  clib_memcpy (m->data + sizeof (struct nlmsghdr), msg_data, msg_len);
+}
+
+static void
+vnet_netlink_msg_add_rtattr (vnet_netlink_msg_t * m, u16 rta_type,
+			     void *rta_data, int rta_data_len)
+{
+  struct rtattr *rta;
+  u8 *p;
+
+  vec_add2 (m->data, p, RTA_LENGTH (rta_data_len));
+  rta = (struct rtattr *) p;
+  rta->rta_type = rta_type;
+  rta->rta_len = RTA_LENGTH (rta_data_len);
+  clib_memcpy (RTA_DATA (rta), rta_data, rta_data_len);
+}
+
+static clib_error_t *
+vnet_netlink_msg_send (vnet_netlink_msg_t * m)
 {
   clib_error_t *err = 0;
-  int sock;
   struct sockaddr_nl ra = { 0 };
-  struct
-  {
-    struct nlmsghdr nh;
-    struct ifinfomsg ifmsg;
-    char attrbuf[512];
-  } req;
-  struct rtattr *rta;
+  int sock;
+  struct nlmsghdr *nh = (struct nlmsghdr *) m->data;
+  nh->nlmsg_len = vec_len (m->data);
 
-  memset (&req, 0, sizeof (req));
   if ((sock = socket (AF_NETLINK, SOCK_RAW, NETLINK_ROUTE)) == -1)
     return clib_error_return_unix (0, "socket(AF_NETLINK)");
 
@@ -59,51 +88,126 @@ vnet_netlink_set_if_attr (int ifindex, unsigned short rta_type, void *data,
       goto error;
     }
 
-  req.nh.nlmsg_len = NLMSG_LENGTH (sizeof (struct ifinfomsg));
-  req.nh.nlmsg_flags = NLM_F_REQUEST;
-  req.nh.nlmsg_type = RTM_SETLINK;
-  req.ifmsg.ifi_family = AF_UNSPEC;
-  req.ifmsg.ifi_index = ifindex;
-  req.ifmsg.ifi_change = 0xffffffff;
-  rta = (struct rtattr *) (((char *) &req) + NLMSG_ALIGN (req.nh.nlmsg_len));
-  rta->rta_type = rta_type;
-  rta->rta_len = RTA_LENGTH (data_len);
-  req.nh.nlmsg_len = NLMSG_ALIGN (req.nh.nlmsg_len) + RTA_LENGTH (data_len);
-  memcpy (RTA_DATA (rta), data, data_len);
-
-  if ((send (sock, &req, req.nh.nlmsg_len, 0)) == -1)
+  if ((send (sock, m->data, vec_len (m->data), 0)) == -1)
     err = clib_error_return_unix (0, "send");
 
 error:
   close (sock);
+  vec_free (m->data);
   return err;
 }
 
 clib_error_t *
-vnet_netlink_set_if_mtu (int ifindex, int mtu)
+vnet_netlink_set_if_namespace (int ifindex, char *net_ns)
 {
+  vnet_netlink_msg_t m;
+  struct ifinfomsg ifmsg = { 0 };
+
   clib_error_t *err;
+  int data;
+  u16 type;
+  u8 *s;
+
+  if (strncmp (net_ns, "pid:", 4) == 0)
+    {
+      data = atoi (net_ns + 4);
+      type = IFLA_NET_NS_PID;
+    }
+  else
+    {
+      if (net_ns[0] == '/')
+	s = format (0, "%s%c", net_ns, 0);
+      else
+	s = format (0, "/var/run/netns/%s%c", net_ns, 0);
+
+      data = open ((char *) s, O_RDONLY);
+      type = IFLA_NET_NS_FD;
+      vec_free (s);
+      if (data == -1)
+	return clib_error_return (0, "namespace '%s' doesn't exist", net_ns);
+    }
 
-  err = vnet_netlink_set_if_attr (ifindex, IFLA_MTU, &mtu, sizeof (int));
+  ifmsg.ifi_family = AF_UNSPEC;
+  ifmsg.ifi_index = ifindex;
+  ifmsg.ifi_change = 0xffffffff;
+  vnet_netlink_msg_init (&m, RTM_SETLINK, NLM_F_REQUEST,
+			 &ifmsg, sizeof (struct ifinfomsg));
+
+  vnet_netlink_msg_add_rtattr (&m, type, &data, sizeof (int));
+  err = vnet_netlink_msg_send (&m);
+
+  if (type == IFLA_NET_NS_FD)
+    close (data);
   return err;
 }
 
 clib_error_t *
-vnet_netlink_set_if_namespace (int ifindex, char *net_ns)
+vnet_netlink_set_if_master (int ifindex, int master_ifindex)
 {
-  clib_error_t *err;
-  int ns_fd;
-  u8 *s;
-  s = format (0, "/var/run/netns/%s%c", net_ns, 0);
-  ns_fd = open ((char *) s, O_RDONLY);
-  vec_free (s);
-  if (ns_fd == -1)
-    return clib_error_return (0, "namespace '%s' doesn't exist", net_ns);
-
-  err =
-    vnet_netlink_set_if_attr (ifindex, IFLA_NET_NS_FD, &ns_fd, sizeof (int));
-  close (ns_fd);
-  return err;
+  vnet_netlink_msg_t m;
+  struct ifinfomsg ifmsg = { 0 };
+
+  ifmsg.ifi_family = AF_UNSPEC;
+  ifmsg.ifi_index = ifindex;
+  ifmsg.ifi_change = 0xffffffff;
+  vnet_netlink_msg_init (&m, RTM_SETLINK, NLM_F_REQUEST,
+			 &ifmsg, sizeof (struct ifinfomsg));
+  vnet_netlink_msg_add_rtattr (&m, IFLA_MASTER, &master_ifindex,
+			       sizeof (int));
+  return vnet_netlink_msg_send (&m);
+}
+
+clib_error_t *
+vnet_netlink_set_if_mtu (int ifindex, int mtu)
+{
+  vnet_netlink_msg_t m;
+  struct ifinfomsg ifmsg = { 0 };
+
+  ifmsg.ifi_family = AF_UNSPEC;
+  ifmsg.ifi_index = ifindex;
+  ifmsg.ifi_change = 0xffffffff;
+  vnet_netlink_msg_init (&m, RTM_SETLINK, NLM_F_REQUEST,
+			 &ifmsg, sizeof (struct ifinfomsg));
+  vnet_netlink_msg_add_rtattr (&m, IFLA_MTU, &mtu, sizeof (int));
+  return vnet_netlink_msg_send (&m);
+}
+
+clib_error_t *
+vnet_netlink_add_ip4_addr (int ifindex, void *addr, int pfx_len)
+{
+  vnet_netlink_msg_t m;
+  struct ifaddrmsg ifa = { 0 };
+
+  ifa.ifa_family = AF_INET;
+  ifa.ifa_prefixlen = pfx_len;
+  ifa.ifa_index = ifindex;
+
+  vnet_netlink_msg_init (&m, RTM_NEWADDR,
+			 NLM_F_REQUEST | NLM_F_CREATE | NLM_F_EXCL,
+			 &ifa, sizeof (struct ifaddrmsg));
+
+  vnet_netlink_msg_add_rtattr (&m, IFA_LOCAL, addr, 4);
+  vnet_netlink_msg_add_rtattr (&m, IFA_ADDRESS, addr, 4);
+  return vnet_netlink_msg_send (&m);
+}
+
+clib_error_t *
+vnet_netlink_add_ip6_addr (int ifindex, void *addr, int pfx_len)
+{
+  vnet_netlink_msg_t m;
+  struct ifaddrmsg ifa = { 0 };
+
+  ifa.ifa_family = AF_INET6;
+  ifa.ifa_prefixlen = pfx_len;
+  ifa.ifa_index = ifindex;
+
+  vnet_netlink_msg_init (&m, RTM_NEWADDR,
+			 NLM_F_REQUEST | NLM_F_CREATE | NLM_F_EXCL,
+			 &ifa, sizeof (struct ifaddrmsg));
+
+  vnet_netlink_msg_add_rtattr (&m, IFA_LOCAL, addr, 16);
+  vnet_netlink_msg_add_rtattr (&m, IFA_ADDRESS, addr, 16);
+  return vnet_netlink_msg_send (&m);
 }
 
 /*