Repair vlib API socket server

- Teach vpp_api_test to send/receive API messages over sockets
- Add memfd-based shared memory
- Add api messages to create memfd-based shared memory segments
- vpp_api_test supports both socket and shared memory segment connections
- vpp_api_test pivot from socket to shared memory API messaging
- add socket client support to libvlibclient.so
- dead client reaper sends ping messages, container-friendly
- dead client reaper falls back to kill (<pid>, 0) live checking
  if e.g. a python app goes silent for tens of seconds
- handle ping messages in python client support code
- teach show api ring about pairwise shared-memory segments
- fix ip probing of already resolved destinations (VPP-998)

We'll need this work to implement proper host-stack client isolation

Change-Id: Ic23b65f75c854d0393d9a2e9d6b122a9551be769
Signed-off-by: Dave Barach <dave@barachs.net>
Signed-off-by: Dave Wallace <dwallacelf@gmail.com>
Signed-off-by: Florin Coras <fcoras@cisco.com>

1 files changed, 194 insertions, 0 deletions

diff --git a/src/svm/memfd.h b/src/svm/memfd.h
new file mode 100644
index 00000000000..3ed4a9ab067
--- /dev/null
+++ b/src/svm/memfd.h
@@ -0,0 +1,194 @@
+/*
+ * Copyright (c) 2017 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_memfd_h__
+#define __included_memfd_h__
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <netinet/in.h>
+#include <signal.h>
+#include <pthread.h>
+#include <unistd.h>
+#include <time.h>
+#include <fcntl.h>
+#include <string.h>
+#include <vppinfra/clib.h>
+#include <vppinfra/vec.h>
+#include <vppinfra/hash.h>
+#include <vppinfra/bitmap.h>
+#include <vppinfra/fifo.h>
+#include <vppinfra/time.h>
+#include <vppinfra/mheap.h>
+#include <vppinfra/heap.h>
+#include <vppinfra/pool.h>
+#include <vppinfra/format.h>
+/* DGMS, memfd syscall not in glibc... */
+#include <vppinfra/linux/syscall.h>
+
+#ifndef MMAP_PAGESIZE
+#define MMAP_PAGESIZE (clib_mem_get_page_size())
+#endif
+
+#define MEMFD_N_OPAQUE 7
+
+typedef struct
+{
+  /* Spin-lock */
+  volatile u32 lock;
+  volatile u32 owner_pid;
+  int recursion_count;
+  u32 tag;			/* for debugging */
+
+  /* The allocation arena */
+  void *heap;
+
+  /* Segment must be mapped at this address, or no supper */
+  u64 memfd_va;
+  /* The actual mmap size */
+  u64 memfd_size;
+  u32 master_pid;
+  u32 slave_pid;
+  u8 *name;
+  void *opaque[MEMFD_N_OPAQUE];
+
+  /* Set when the master application thinks it's time to make the donuts */
+  volatile u32 ready;
+
+  /* Needed to make unique MAC addresses, etc. */
+  u32 master_index;
+} memfd_shared_header_t;
+
+typedef struct
+{
+  memfd_shared_header_t *sh;
+  int fd;
+  u64 memfd_size;
+  u32 my_pid;
+  u32 vlib_hw_if_index;
+  uword requested_va;
+  int i_am_master;
+  u32 per_interface_next_index;
+  u32 *rx_queue;
+  u8 *name;
+} memfd_private_t;
+
+always_inline void
+memfd_lock (memfd_shared_header_t * h, u32 my_pid, u32 tag)
+{
+  if (h->owner_pid == my_pid)
+    {
+      h->recursion_count++;
+      return;
+    }
+
+  while (__sync_lock_test_and_set (&h->lock, 1))
+    ;
+
+  h->owner_pid = my_pid;
+  h->recursion_count = 1;
+  h->tag = tag;
+}
+
+always_inline void
+memfd_lock_non_recursive (memfd_shared_header_t * h, u32 tag)
+{
+  while (__sync_lock_test_and_set (&h->lock, 1))
+    ;
+
+  h->tag = tag;
+}
+
+always_inline void
+memfd_unlock (memfd_shared_header_t * h)
+{
+  if (--h->recursion_count == 0)
+    {
+      h->owner_pid = 0;
+      h->tag = 0;
+      CLIB_MEMORY_BARRIER ();
+      h->lock = 0;
+    }
+}
+
+always_inline void
+memfd_unlock_non_recursive (memfd_shared_header_t * h)
+{
+  h->tag = 0;
+  CLIB_MEMORY_BARRIER ();
+  h->lock = 0;
+}
+
+static inline void *
+memfd_push_heap (memfd_shared_header_t * sh)
+{
+  u8 *oldheap;
+  oldheap = clib_mem_set_heap (sh->heap);
+  return ((void *) oldheap);
+}
+
+static inline void
+memfd_pop_heap (void *oldheap)
+{
+  clib_mem_set_heap (oldheap);
+}
+
+#define foreach_memfd_api_error                  \
+_(NO_NAME, "No shared segment name", -100)      \
+_(NO_SIZE, "Size not set (master)", -101)       \
+_(CREATE_FAILURE, "Create failed", -102)        \
+_(SET_SIZE, "Set size failed", -103)		\
+_(MMAP, "mmap failed", -104)			\
+_(SLAVE_TIMEOUT, "Slave map timeout", -105)
+
+typedef enum
+{
+#define _(n,s,c) MEMFD_API_ERROR_##n = c,
+  foreach_memfd_api_error
+#undef _
+} memfd_api_error_enum_t;
+
+#define MEMFD_API_ERROR_NO_NAME	(-10)
+
+int memfd_master_init (memfd_private_t * memfd, u32 master_index);
+int memfd_slave_init (memfd_private_t * memfd);
+void memfd_delete (memfd_private_t * memfd);
+
+/* These do not belong here, but the original keeps running around... */
+/* $$$$ work w/ Damjan to fix properly */
+
+#ifndef F_LINUX_SPECIFIC_BASE
+#define F_LINUX_SPECIFIC_BASE 1024
+#endif
+#define MFD_ALLOW_SEALING       0x0002U
+#define F_ADD_SEALS (F_LINUX_SPECIFIC_BASE + 9)
+#define F_GET_SEALS (F_LINUX_SPECIFIC_BASE + 10)
+
+#define F_SEAL_SEAL     0x0001	/* prevent further seals from being set */
+#define F_SEAL_SHRINK   0x0002	/* prevent file from shrinking */
+#define F_SEAL_GROW     0x0004	/* prevent file from growing */
+#define F_SEAL_WRITE    0x0008	/* prevent writes */
+
+#endif /* __included_memfd_h__ */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */