vppinfra: add abstract socket & netns fns

* Add clib_socket_init support for abstract sockets
if name starts with an '@'
* Add clib_socket_init_netns to open socket in netns
* Add clib_netns_open

Type: feature

Change-Id: I89637ad657c702ec38ddecb5c03a1673d0dfb104
Signed-off-by: Nathan Skrzypczak <nathan.skrzypczak@gmail.com>

2 files changed, 87 insertions, 0 deletions

diff --git a/src/vppinfra/linux/netns.c b/src/vppinfra/linux/netns.c
new file mode 100644
index 00000000000..2bd62bd7d92
--- /dev/null
+++ b/src/vppinfra/linux/netns.c
@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2021 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define _GNU_SOURCE
+#include <fcntl.h>
+#include <sched.h>
+
+#include <vppinfra/format.h>
+
+__clib_export int
+clib_netns_open (u8 *netns_u8)
+{
+  char *netns = (char *) netns_u8;
+  u8 *s = 0;
+  int fd;
+
+  if ((NULL) == netns)
+    s = format (0, "/proc/self/ns/net");
+  else if (strncmp (netns, "pid:", 4) == 0)
+    s = format (0, "/proc/%u/ns/net%c", atoi (netns + 4), 0);
+  else if (netns[0] == '/')
+    s = format (0, "%s%c", netns, 0);
+  else
+    s = format (0, "/var/run/netns/%s%c", netns, 0);
+
+  fd = open ((char *) s, O_RDONLY);
+  vec_free (s);
+  return fd;
+}
+
+__clib_export int
+clib_setns (int nfd)
+{
+  return setns (nfd, CLONE_NEWNET);
+}
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/src/vppinfra/linux/netns.h b/src/vppinfra/linux/netns.h
new file mode 100644
index 00000000000..5a094607953
--- /dev/null
+++ b/src/vppinfra/linux/netns.h
@@ -0,0 +1,32 @@
+/*
+ * Copyright (c) 2021 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef included_vppinfra_netns_h
+#define included_vppinfra_netns_h
+
+#include <vppinfra/clib.h>
+
+int clib_netns_open (u8 *netns);
+int clib_setns (int nfd);
+
+#endif /* included_vppinfra_netns_h */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */