1 files changed, 553 insertions, 0 deletions

diff --git a/src/vlib/unix/plugin.c b/src/vlib/unix/plugin.c
new file mode 100644
index 00000000..c2741aaa
--- /dev/null
+++ b/src/vlib/unix/plugin.c
@@ -0,0 +1,553 @@
+/*
+ * plugin.c: plugin handling
+ *
+ * Copyright (c) 2011 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.
+ */
+
+#include <vlib/unix/plugin.h>
+#include <vppinfra/elf.h>
+#include <dlfcn.h>
+#include <dirent.h>
+
+plugin_main_t vlib_plugin_main;
+
+char *vlib_plugin_path __attribute__ ((weak));
+char *vlib_plugin_path = "";
+char *vlib_plugin_app_version __attribute__ ((weak));
+char *vlib_plugin_app_version = "";
+
+void *
+vlib_get_plugin_symbol (char *plugin_name, char *symbol_name)
+{
+  plugin_main_t *pm = &vlib_plugin_main;
+  uword *p;
+  plugin_info_t *pi;
+
+  if ((p = hash_get_mem (pm->plugin_by_name_hash, plugin_name)) == 0)
+    return 0;
+
+  pi = vec_elt_at_index (pm->plugin_info, p[0]);
+  return dlsym (pi->handle, symbol_name);
+}
+
+static char *
+str_array_to_vec (char *array, int len)
+{
+  char c, *r = 0;
+  int n = 0;
+
+  do
+    {
+      c = array[n];
+      vec_add1 (r, c);
+    }
+  while (c && ++n < len);
+
+  if (c)
+    vec_add1 (r, 0);
+
+  return r;
+}
+
+static int
+load_one_plugin (plugin_main_t * pm, plugin_info_t * pi, int from_early_init)
+{
+  void *handle;
+  clib_error_t *error;
+  elf_main_t em = { 0 };
+  elf_section_t *section;
+  u8 *data;
+  char *version_required;
+  vlib_plugin_registration_t *reg;
+  plugin_config_t *pc = 0;
+  uword *p;
+
+  if (elf_read_file (&em, (char *) pi->filename))
+    return -1;
+
+  error = elf_get_section_by_name (&em, ".vlib_plugin_registration",
+				   &section);
+  if (error)
+    {
+      clib_warning ("Not a plugin: %s\n", (char *) pi->name);
+      return -1;
+    }
+
+  data = elf_get_section_contents (&em, section->index, 1);
+  reg = (vlib_plugin_registration_t *) data;
+
+  if (vec_len (data) != sizeof (*reg))
+    {
+      clib_warning ("vlib_plugin_registration size mismatch in plugin %s\n",
+		    (char *) pi->name);
+      goto error;
+    }
+
+  p = hash_get_mem (pm->config_index_by_name, pi->name);
+  if (p)
+    {
+      pc = vec_elt_at_index (pm->configs, p[0]);
+      if (pc->is_disabled)
+	{
+	  clib_warning ("Plugin disabled: %s", pi->name);
+	  goto error;
+	}
+      if (reg->default_disabled && pc->is_enabled == 0)
+	{
+	  clib_warning ("Plugin disabled (default): %s", pi->name);
+	  goto error;
+	}
+    }
+  else if (reg->default_disabled)
+    {
+      clib_warning ("Plugin disabled (default): %s", pi->name);
+      goto error;
+    }
+
+  version_required = str_array_to_vec ((char *) &reg->version_required,
+				       sizeof (reg->version_required));
+
+  if ((strlen (version_required) > 0) &&
+      (strncmp (vlib_plugin_app_version, version_required,
+		strlen (version_required))))
+    {
+      clib_warning ("Plugin %s version mismatch: %s != %s",
+		    pi->name, vlib_plugin_app_version, reg->version_required);
+      if (!(pc && pc->skip_version_check == 1))
+	{
+	  vec_free (version_required);
+	  goto error;
+	}
+    }
+
+  vec_free (version_required);
+  vec_free (data);
+  elf_main_free (&em);
+
+  handle = dlopen ((char *) pi->filename, RTLD_LAZY);
+
+  if (handle == 0)
+    {
+      clib_warning ("%s", dlerror ());
+      clib_warning ("Failed to load plugin '%s'", pi->name);
+      os_exit (1);
+    }
+
+  pi->handle = handle;
+
+  reg = dlsym (pi->handle, "vlib_plugin_registration");
+
+  if (reg == 0)
+    {
+      /* This should never happen unless somebody chagnes registration macro */
+      clib_warning ("Missing plugin registration in plugin '%s'", pi->name);
+      os_exit (1);
+    }
+
+  pi->reg = reg;
+  pi->version = str_array_to_vec ((char *) &reg->version,
+				  sizeof (reg->version));
+
+  if (reg->early_init)
+    {
+      clib_error_t *(*ei) (vlib_main_t *);
+      void *h;
+
+      h = dlsym (pi->handle, reg->early_init);
+      if (h)
+	{
+	  ei = h;
+	  error = (*ei) (pm->vlib_main);
+	  if (error)
+	    {
+	      clib_error_report (error);
+	      os_exit (1);
+	    }
+	}
+      else
+	clib_warning ("Plugin %s: early init function %s set but not found",
+		      (char *) pi->name, reg->early_init);
+    }
+
+  if (reg->description)
+    clib_warning ("Loaded plugin: %s (%s)", pi->name, reg->description);
+  else
+    clib_warning ("Loaded plugin: %s", pi->name);
+
+  return 0;
+error:
+  vec_free (data);
+  elf_main_free (&em);
+  return -1;
+}
+
+static u8 **
+split_plugin_path (plugin_main_t * pm)
+{
+  int i;
+  u8 **rv = 0;
+  u8 *path = pm->plugin_path;
+  u8 *this = 0;
+
+  for (i = 0; i < vec_len (pm->plugin_path); i++)
+    {
+      if (path[i] != ':')
+	{
+	  vec_add1 (this, path[i]);
+	  continue;
+	}
+      vec_add1 (this, 0);
+      vec_add1 (rv, this);
+      this = 0;
+    }
+  if (this)
+    {
+      vec_add1 (this, 0);
+      vec_add1 (rv, this);
+    }
+  return rv;
+}
+
+static int
+plugin_name_sort_cmp (void *a1, void *a2)
+{
+  plugin_info_t *p1 = a1;
+  plugin_info_t *p2 = a2;
+
+  return strcmp ((char *) p1->name, (char *) p2->name);
+}
+
+int
+vlib_load_new_plugins (plugin_main_t * pm, int from_early_init)
+{
+  DIR *dp;
+  struct dirent *entry;
+  struct stat statb;
+  uword *p;
+  plugin_info_t *pi;
+  u8 **plugin_path;
+  u32 *load_fail_indices = 0;
+  int i;
+
+  plugin_path = split_plugin_path (pm);
+
+  for (i = 0; i < vec_len (plugin_path); i++)
+    {
+      dp = opendir ((char *) plugin_path[i]);
+
+      if (dp == 0)
+	continue;
+
+      while ((entry = readdir (dp)))
+	{
+	  u8 *plugin_name;
+	  u8 *filename;
+
+	  if (pm->plugin_name_filter)
+	    {
+	      int j;
+	      for (j = 0; j < vec_len (pm->plugin_name_filter); j++)
+		if (entry->d_name[j] != pm->plugin_name_filter[j])
+		  goto next;
+	    }
+
+	  filename = format (0, "%s/%s%c", plugin_path[i], entry->d_name, 0);
+
+	  /* Only accept .so */
+	  char *ext = strrchr ((const char *) filename, '.');
+	  /* unreadable */
+	  if (!ext || (strcmp (ext, ".so") != 0) ||
+	      stat ((char *) filename, &statb) < 0)
+	    {
+	    ignore:
+	      vec_free (filename);
+	      continue;
+	    }
+
+	  /* a dir or other things which aren't plugins */
+	  if (!S_ISREG (statb.st_mode))
+	    goto ignore;
+
+	  plugin_name = format (0, "%s%c", entry->d_name, 0);
+	  /* Have we seen this plugin already? */
+	  p = hash_get_mem (pm->plugin_by_name_hash, plugin_name);
+	  if (p == 0)
+	    {
+	      /* No, add it to the plugin vector */
+	      vec_add2 (pm->plugin_info, pi, 1);
+	      pi->name = plugin_name;
+	      pi->filename = filename;
+	      pi->file_info = statb;
+	      hash_set_mem (pm->plugin_by_name_hash, plugin_name,
+			    pi - pm->plugin_info);
+	    }
+	next:
+	  ;
+	}
+      closedir (dp);
+      vec_free (plugin_path[i]);
+    }
+  vec_free (plugin_path);
+
+
+  /*
+   * Sort the plugins by name. This is important.
+   * API traces contain absolute message numbers.
+   * Loading plugins in directory (vs. alphabetical) order
+   * makes trace replay incredibly fragile.
+   */
+  vec_sort_with_function (pm->plugin_info, plugin_name_sort_cmp);
+
+  /*
+   * Attempt to load the plugins
+   */
+  for (i = 0; i < vec_len (pm->plugin_info); i++)
+    {
+      pi = vec_elt_at_index (pm->plugin_info, i);
+
+      if (load_one_plugin (pm, pi, from_early_init))
+	{
+	  /* Make a note of any which fail to load */
+	  vec_add1 (load_fail_indices, i);
+	  hash_unset_mem (pm->plugin_by_name_hash, pi->name);
+	  vec_free (pi->name);
+	  vec_free (pi->filename);
+	}
+    }
+
+  /* Remove plugin info vector elements corresponding to load failures */
+  if (vec_len (load_fail_indices) > 0)
+    {
+      for (i = vec_len (load_fail_indices) - 1; i >= 0; i--)
+	vec_delete (pm->plugin_info, 1, load_fail_indices[i]);
+      vec_free (load_fail_indices);
+    }
+
+  /* Recreate the plugin name hash */
+  for (i = 0; i < vec_len (pm->plugin_info); i++)
+    {
+      pi = vec_elt_at_index (pm->plugin_info, i);
+      hash_unset_mem (pm->plugin_by_name_hash, pi->name);
+      hash_set_mem (pm->plugin_by_name_hash, pi->name, pi - pm->plugin_info);
+    }
+
+  return 0;
+}
+
+int
+vlib_plugin_early_init (vlib_main_t * vm)
+{
+  plugin_main_t *pm = &vlib_plugin_main;
+
+  if (pm->plugin_path == 0)
+    pm->plugin_path = format (0, "%s%c", vlib_plugin_path, 0);
+
+  clib_warning ("plugin path %s", pm->plugin_path);
+
+  pm->plugin_by_name_hash = hash_create_string (0, sizeof (uword));
+  pm->vlib_main = vm;
+
+  return vlib_load_new_plugins (pm, 1 /* from_early_init */ );
+}
+
+static clib_error_t *
+vlib_plugins_show_cmd_fn (vlib_main_t * vm,
+			  unformat_input_t * input, vlib_cli_command_t * cmd)
+{
+  plugin_main_t *pm = &vlib_plugin_main;
+  u8 *s = 0;
+  u8 *key = 0;
+  uword value = 0;
+  int index = 1;
+  plugin_info_t *pi;
+
+  s = format (s, " Plugin path is: %s\n\n", pm->plugin_path);
+  s = format (s, "     %-41s%-33s%s\n", "Plugin", "Version", "Description");
+
+  /* *INDENT-OFF* */
+  hash_foreach_mem (key, value, pm->plugin_by_name_hash,
+    {
+      if (key != 0)
+        {
+          pi = vec_elt_at_index (pm->plugin_info, value);
+          s = format (s, "%3d. %-40s %-32s %s\n", index, key, pi->version,
+		      pi->reg->description ? pi->reg->description : "");
+	  index++;
+        }
+    });
+  /* *INDENT-ON* */
+
+  vlib_cli_output (vm, "%v", s);
+  vec_free (s);
+  return 0;
+}
+
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (plugins_show_cmd, static) =
+{
+  .path = "show plugins",
+  .short_help = "show loaded plugins",
+  .function = vlib_plugins_show_cmd_fn,
+};
+/* *INDENT-ON* */
+
+static clib_error_t *
+config_one_plugin (vlib_main_t * vm, char *name, unformat_input_t * input)
+{
+  plugin_main_t *pm = &vlib_plugin_main;
+  plugin_config_t *pc;
+  clib_error_t *error = 0;
+  uword *p;
+  int is_enable = 0;
+  int is_disable = 0;
+  int skip_version_check = 0;
+
+  if (pm->config_index_by_name == 0)
+    pm->config_index_by_name = hash_create_string (0, sizeof (uword));
+
+  p = hash_get_mem (pm->config_index_by_name, name);
+
+  if (p)
+    {
+      error = clib_error_return (0, "plugin '%s' already configured", name);
+      goto done;
+    }
+
+  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
+    {
+      if (unformat (input, "enable"))
+	is_enable = 1;
+      else if (unformat (input, "disable"))
+	is_disable = 1;
+      else if (unformat (input, "skip-version-check"))
+	skip_version_check = 1;
+      else
+	{
+	  error = clib_error_return (0, "unknown input '%U'",
+				     format_unformat_error, input);
+	  goto done;
+	}
+    }
+
+  if (is_enable && is_disable)
+    {
+      error = clib_error_return (0, "please specify either enable or disable"
+				 " for plugin '%s'", name);
+      goto done;
+    }
+
+  vec_add2 (pm->configs, pc, 1);
+  hash_set_mem (pm->config_index_by_name, name, pc - pm->configs);
+  pc->is_enabled = is_enable;
+  pc->is_disabled = is_disable;
+  pc->skip_version_check = skip_version_check;
+  pc->name = name;
+
+done:
+  return error;
+}
+
+clib_error_t *
+vlib_plugin_config (vlib_main_t * vm, unformat_input_t * input)
+{
+  plugin_main_t *pm = &vlib_plugin_main;
+  clib_error_t *error = 0;
+  unformat_input_t in;
+
+  unformat_init (&in, 0, 0);
+
+  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
+    {
+      u8 *s, *v;
+      if (unformat (input, "%s %v", &s, &v))
+	{
+	  if (strncmp ((const char *) s, "plugins", 8) == 0)
+	    {
+	      if (vec_len (in.buffer) > 0)
+		vec_add1 (in.buffer, ' ');
+	      vec_add (in.buffer, v, vec_len (v));
+	    }
+	}
+      else
+	{
+	  error = clib_error_return (0, "unknown input '%U'",
+				     format_unformat_error, input);
+	  goto done;
+	}
+
+      vec_free (v);
+      vec_free (s);
+    }
+done:
+  input = &in;
+  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
+    {
+      unformat_input_t sub_input;
+      u8 *s = 0;
+      if (unformat (input, "path %s", &s))
+	pm->plugin_path = s;
+      else if (unformat (input, "plugin %s %U", &s,
+			 unformat_vlib_cli_sub_input, &sub_input))
+	{
+	  error = config_one_plugin (vm, (char *) s, &sub_input);
+	  unformat_free (&sub_input);
+	  if (error)
+	    goto done2;
+	}
+      else
+	{
+	  error = clib_error_return (0, "unknown input '%U'",
+				     format_unformat_error, input);
+	  {
+	    vec_free (s);
+	    goto done2;
+	  }
+	}
+    }
+
+done2:
+  unformat_free (&in);
+  return error;
+}
+
+/* discard whole 'plugins' section, as it is already consumed prior to
+   plugin load */
+static clib_error_t *
+plugins_config (vlib_main_t * vm, unformat_input_t * input)
+{
+  u8 *junk;
+
+  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
+    {
+      if (unformat (input, "%s", &junk))
+	{
+	  vec_free (junk);
+	  return 0;
+	}
+      else
+	return clib_error_return (0, "unknown input '%U'",
+				  format_unformat_error, input);
+    }
+  return 0;
+}
+
+VLIB_CONFIG_FUNCTION (plugins_config, "plugins");
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */