FD.io VPP  v17.07-30-g839fa73
Vector Packet Processing
plugin.c
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1 /*
2  * plugin.c: plugin handling
3  *
4  * Copyright (c) 2011 Cisco and/or its affiliates.
5  * Licensed under the Apache License, Version 2.0 (the "License");
6  * you may not use this file except in compliance with the License.
7  * You may obtain a copy of the License at:
8  *
9  * http://www.apache.org/licenses/LICENSE-2.0
10  *
11  * Unless required by applicable law or agreed to in writing, software
12  * distributed under the License is distributed on an "AS IS" BASIS,
13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  * See the License for the specific language governing permissions and
15  * limitations under the License.
16  */
17 
18 #include <vlib/unix/plugin.h>
19 #include <vppinfra/elf.h>
20 #include <dlfcn.h>
21 #include <dirent.h>
22 
24 
25 char *vlib_plugin_path __attribute__ ((weak));
26 char *vlib_plugin_path = "";
27 char *vlib_plugin_app_version __attribute__ ((weak));
28 char *vlib_plugin_app_version = "";
29 
30 void *
31 vlib_get_plugin_symbol (char *plugin_name, char *symbol_name)
32 {
34  uword *p;
35  plugin_info_t *pi;
36 
37  if ((p = hash_get_mem (pm->plugin_by_name_hash, plugin_name)) == 0)
38  return 0;
39 
40  pi = vec_elt_at_index (pm->plugin_info, p[0]);
41  return dlsym (pi->handle, symbol_name);
42 }
43 
44 static char *
45 str_array_to_vec (char *array, int len)
46 {
47  char c, *r = 0;
48  int n = 0;
49 
50  do
51  {
52  c = array[n];
53  vec_add1 (r, c);
54  }
55  while (c && ++n < len);
56 
57  if (c)
58  vec_add1 (r, 0);
59 
60  return r;
61 }
62 
63 static int
64 load_one_plugin (plugin_main_t * pm, plugin_info_t * pi, int from_early_init)
65 {
66  void *handle;
67  clib_error_t *error;
68  elf_main_t em = { 0 };
69  elf_section_t *section;
70  u8 *data;
71  char *version_required;
72  vlib_plugin_registration_t *reg;
73  plugin_config_t *pc = 0;
74  uword *p;
75 
76  if (elf_read_file (&em, (char *) pi->filename))
77  return -1;
78 
79  error = elf_get_section_by_name (&em, ".vlib_plugin_registration",
80  &section);
81  if (error)
82  {
83  clib_warning ("Not a plugin: %s\n", (char *) pi->name);
84  return -1;
85  }
86 
87  data = elf_get_section_contents (&em, section->index, 1);
88  reg = (vlib_plugin_registration_t *) data;
89 
90  if (vec_len (data) != sizeof (*reg))
91  {
92  clib_warning ("vlib_plugin_registration size mismatch in plugin %s\n",
93  (char *) pi->name);
94  goto error;
95  }
96 
97  p = hash_get_mem (pm->config_index_by_name, pi->name);
98  if (p)
99  {
100  pc = vec_elt_at_index (pm->configs, p[0]);
101  if (pc->is_disabled)
102  {
103  clib_warning ("Plugin disabled: %s", pi->name);
104  goto error;
105  }
106  if (reg->default_disabled && pc->is_enabled == 0)
107  {
108  clib_warning ("Plugin disabled (default): %s", pi->name);
109  goto error;
110  }
111  }
112  else if (reg->default_disabled)
113  {
114  clib_warning ("Plugin disabled (default): %s", pi->name);
115  goto error;
116  }
117 
118  version_required = str_array_to_vec ((char *) &reg->version_required,
119  sizeof (reg->version_required));
120 
121  if ((strlen (version_required) > 0) &&
122  (strncmp (vlib_plugin_app_version, version_required,
123  strlen (version_required))))
124  {
125  clib_warning ("Plugin %s version mismatch: %s != %s",
126  pi->name, vlib_plugin_app_version, reg->version_required);
127  if (!(pc && pc->skip_version_check == 1))
128  {
129  vec_free (version_required);
130  goto error;
131  }
132  }
133 
134  vec_free (version_required);
135  vec_free (data);
136  elf_main_free (&em);
137 
138  handle = dlopen ((char *) pi->filename, RTLD_LAZY);
139 
140  if (handle == 0)
141  {
142  clib_warning ("%s", dlerror ());
143  clib_warning ("Failed to load plugin '%s'", pi->name);
144  os_exit (1);
145  }
146 
147  pi->handle = handle;
148 
149  reg = dlsym (pi->handle, "vlib_plugin_registration");
150 
151  if (reg == 0)
152  {
153  /* This should never happen unless somebody chagnes registration macro */
154  clib_warning ("Missing plugin registration in plugin '%s'", pi->name);
155  os_exit (1);
156  }
157 
158  pi->reg = reg;
159  pi->version = str_array_to_vec ((char *) &reg->version,
160  sizeof (reg->version));
161 
162  if (reg->early_init)
163  {
164  clib_error_t *(*ei) (vlib_main_t *);
165  void *h;
166 
167  h = dlsym (pi->handle, reg->early_init);
168  if (h)
169  {
170  ei = h;
171  error = (*ei) (pm->vlib_main);
172  if (error)
173  {
174  clib_error_report (error);
175  os_exit (1);
176  }
177  }
178  else
179  clib_warning ("Plugin %s: early init function %s set but not found",
180  (char *) pi->name, reg->early_init);
181  }
182 
183  if (reg->description)
184  clib_warning ("Loaded plugin: %s (%s)", pi->name, reg->description);
185  else
186  clib_warning ("Loaded plugin: %s", pi->name);
187 
188  return 0;
189 error:
190  vec_free (data);
191  elf_main_free (&em);
192  return -1;
193 }
194 
195 static u8 **
197 {
198  int i;
199  u8 **rv = 0;
200  u8 *path = pm->plugin_path;
201  u8 *this = 0;
202 
203  for (i = 0; i < vec_len (pm->plugin_path); i++)
204  {
205  if (path[i] != ':')
206  {
207  vec_add1 (this, path[i]);
208  continue;
209  }
210  vec_add1 (this, 0);
211  vec_add1 (rv, this);
212  this = 0;
213  }
214  if (this)
215  {
216  vec_add1 (this, 0);
217  vec_add1 (rv, this);
218  }
219  return rv;
220 }
221 
222 static int
223 plugin_name_sort_cmp (void *a1, void *a2)
224 {
225  plugin_info_t *p1 = a1;
226  plugin_info_t *p2 = a2;
227 
228  return strcmp ((char *) p1->name, (char *) p2->name);
229 }
230 
231 int
232 vlib_load_new_plugins (plugin_main_t * pm, int from_early_init)
233 {
234  DIR *dp;
235  struct dirent *entry;
236  struct stat statb;
237  uword *p;
238  plugin_info_t *pi;
239  u8 **plugin_path;
240  u32 *load_fail_indices = 0;
241  int i;
242 
243  plugin_path = split_plugin_path (pm);
244 
245  for (i = 0; i < vec_len (plugin_path); i++)
246  {
247  dp = opendir ((char *) plugin_path[i]);
248 
249  if (dp == 0)
250  continue;
251 
252  while ((entry = readdir (dp)))
253  {
254  u8 *plugin_name;
255  u8 *filename;
256 
257  if (pm->plugin_name_filter)
258  {
259  int j;
260  for (j = 0; j < vec_len (pm->plugin_name_filter); j++)
261  if (entry->d_name[j] != pm->plugin_name_filter[j])
262  goto next;
263  }
264 
265  filename = format (0, "%s/%s%c", plugin_path[i], entry->d_name, 0);
266 
267  /* Only accept .so */
268  char *ext = strrchr ((const char *) filename, '.');
269  /* unreadable */
270  if (!ext || (strcmp (ext, ".so") != 0) ||
271  stat ((char *) filename, &statb) < 0)
272  {
273  ignore:
274  vec_free (filename);
275  continue;
276  }
277 
278  /* a dir or other things which aren't plugins */
279  if (!S_ISREG (statb.st_mode))
280  goto ignore;
281 
282  plugin_name = format (0, "%s%c", entry->d_name, 0);
283  /* Have we seen this plugin already? */
284  p = hash_get_mem (pm->plugin_by_name_hash, plugin_name);
285  if (p == 0)
286  {
287  /* No, add it to the plugin vector */
288  vec_add2 (pm->plugin_info, pi, 1);
289  pi->name = plugin_name;
290  pi->filename = filename;
291  pi->file_info = statb;
292  hash_set_mem (pm->plugin_by_name_hash, plugin_name,
293  pi - pm->plugin_info);
294  }
295  next:
296  ;
297  }
298  closedir (dp);
299  vec_free (plugin_path[i]);
300  }
301  vec_free (plugin_path);
302 
303 
304  /*
305  * Sort the plugins by name. This is important.
306  * API traces contain absolute message numbers.
307  * Loading plugins in directory (vs. alphabetical) order
308  * makes trace replay incredibly fragile.
309  */
311 
312  /*
313  * Attempt to load the plugins
314  */
315  for (i = 0; i < vec_len (pm->plugin_info); i++)
316  {
317  pi = vec_elt_at_index (pm->plugin_info, i);
318 
319  if (load_one_plugin (pm, pi, from_early_init))
320  {
321  /* Make a note of any which fail to load */
322  vec_add1 (load_fail_indices, i);
324  vec_free (pi->name);
325  vec_free (pi->filename);
326  }
327  }
328 
329  /* Remove plugin info vector elements corresponding to load failures */
330  if (vec_len (load_fail_indices) > 0)
331  {
332  for (i = vec_len (load_fail_indices) - 1; i >= 0; i--)
333  vec_delete (pm->plugin_info, 1, load_fail_indices[i]);
334  vec_free (load_fail_indices);
335  }
336 
337  /* Recreate the plugin name hash */
338  for (i = 0; i < vec_len (pm->plugin_info); i++)
339  {
340  pi = vec_elt_at_index (pm->plugin_info, i);
342  hash_set_mem (pm->plugin_by_name_hash, pi->name, pi - pm->plugin_info);
343  }
344 
345  return 0;
346 }
347 
348 int
350 {
352 
353  if (pm->plugin_path == 0)
354  pm->plugin_path = format (0, "%s%c", vlib_plugin_path, 0);
355 
356  clib_warning ("plugin path %s", pm->plugin_path);
357 
358  pm->plugin_by_name_hash = hash_create_string (0, sizeof (uword));
359  pm->vlib_main = vm;
360 
361  return vlib_load_new_plugins (pm, 1 /* from_early_init */ );
362 }
363 
364 static clib_error_t *
366  unformat_input_t * input, vlib_cli_command_t * cmd)
367 {
369  u8 *s = 0;
370  u8 *key = 0;
371  uword value = 0;
372  int index = 1;
373  plugin_info_t *pi;
374 
375  s = format (s, " Plugin path is: %s\n\n", pm->plugin_path);
376  s = format (s, " %-41s%-33s%s\n", "Plugin", "Version", "Description");
377 
378  /* *INDENT-OFF* */
379  hash_foreach_mem (key, value, pm->plugin_by_name_hash,
380  {
381  if (key != 0)
382  {
383  pi = vec_elt_at_index (pm->plugin_info, value);
384  s = format (s, "%3d. %-40s %-32s %s\n", index, key, pi->version,
385  pi->reg->description ? pi->reg->description : "");
386  index++;
387  }
388  });
389  /* *INDENT-ON* */
390 
391  vlib_cli_output (vm, "%v", s);
392  vec_free (s);
393  return 0;
394 }
395 
396 /* *INDENT-OFF* */
397 VLIB_CLI_COMMAND (plugins_show_cmd, static) =
398 {
399  .path = "show plugins",
400  .short_help = "show loaded plugins",
401  .function = vlib_plugins_show_cmd_fn,
402 };
403 /* *INDENT-ON* */
404 
405 static clib_error_t *
406 config_one_plugin (vlib_main_t * vm, char *name, unformat_input_t * input)
407 {
409  plugin_config_t *pc;
410  clib_error_t *error = 0;
411  uword *p;
412  int is_enable = 0;
413  int is_disable = 0;
414  int skip_version_check = 0;
415 
416  if (pm->config_index_by_name == 0)
417  pm->config_index_by_name = hash_create_string (0, sizeof (uword));
418 
419  p = hash_get_mem (pm->config_index_by_name, name);
420 
421  if (p)
422  {
423  error = clib_error_return (0, "plugin '%s' already configured", name);
424  goto done;
425  }
426 
428  {
429  if (unformat (input, "enable"))
430  is_enable = 1;
431  else if (unformat (input, "disable"))
432  is_disable = 1;
433  else if (unformat (input, "skip-version-check"))
434  skip_version_check = 1;
435  else
436  {
437  error = clib_error_return (0, "unknown input '%U'",
438  format_unformat_error, input);
439  goto done;
440  }
441  }
442 
443  if (is_enable && is_disable)
444  {
445  error = clib_error_return (0, "please specify either enable or disable"
446  " for plugin '%s'", name);
447  goto done;
448  }
449 
450  vec_add2 (pm->configs, pc, 1);
451  hash_set_mem (pm->config_index_by_name, name, pc - pm->configs);
452  pc->is_enabled = is_enable;
453  pc->is_disabled = is_disable;
454  pc->skip_version_check = skip_version_check;
455  pc->name = name;
456 
457 done:
458  return error;
459 }
460 
461 clib_error_t *
463 {
465  clib_error_t *error = 0;
466  unformat_input_t in;
467 
468  unformat_init (&in, 0, 0);
469 
471  {
472  u8 *s, *v;
473  if (unformat (input, "%s %v", &s, &v))
474  {
475  if (strncmp ((const char *) s, "plugins", 8) == 0)
476  {
477  if (vec_len (in.buffer) > 0)
478  vec_add1 (in.buffer, ' ');
479  vec_add (in.buffer, v, vec_len (v));
480  }
481  }
482  else
483  {
484  error = clib_error_return (0, "unknown input '%U'",
485  format_unformat_error, input);
486  goto done;
487  }
488 
489  vec_free (v);
490  vec_free (s);
491  }
492 done:
493  input = &in;
495  {
496  unformat_input_t sub_input;
497  u8 *s = 0;
498  if (unformat (input, "path %s", &s))
499  pm->plugin_path = s;
500  else if (unformat (input, "plugin %s %U", &s,
501  unformat_vlib_cli_sub_input, &sub_input))
502  {
503  error = config_one_plugin (vm, (char *) s, &sub_input);
504  unformat_free (&sub_input);
505  if (error)
506  goto done2;
507  }
508  else
509  {
510  error = clib_error_return (0, "unknown input '%U'",
511  format_unformat_error, input);
512  {
513  vec_free (s);
514  goto done2;
515  }
516  }
517  }
518 
519 done2:
520  unformat_free (&in);
521  return error;
522 }
523 
524 /* discard whole 'plugins' section, as it is already consumed prior to
525  plugin load */
526 static clib_error_t *
528 {
529  u8 *junk;
530 
532  {
533  if (unformat (input, "%s", &junk))
534  {
535  vec_free (junk);
536  return 0;
537  }
538  else
539  return clib_error_return (0, "unknown input '%U'",
540  format_unformat_error, input);
541  }
542  return 0;
543 }
544 
546 
547 /*
548  * fd.io coding-style-patch-verification: ON
549  *
550  * Local Variables:
551  * eval: (c-set-style "gnu")
552  * End:
553  */
plugin_config_t * configs
Definition: plugin.h:100
static void elf_main_free(elf_main_t *em)
Definition: elf.h:926
u8 * filename
Definition: plugin.h:72
u8 * plugin_path
Definition: plugin.h:96
sll srl srl sll sra u16x4 i
Definition: vector_sse2.h:337
u8 * plugin_name_filter
Definition: plugin.h:97
static clib_error_t * plugins_config(vlib_main_t *vm, unformat_input_t *input)
Definition: plugin.c:527
char * name
Definition: plugin.h:83
static int plugin_name_sort_cmp(void *a1, void *a2)
Definition: plugin.c:223
u32 index
Definition: elf.h:857
#define vec_add1(V, E)
Add 1 element to end of vector (unspecified alignment).
Definition: vec.h:522
clib_error_t * vlib_plugin_config(vlib_main_t *vm, unformat_input_t *input)
Definition: plugin.c:462
vlib_main_t * vlib_main
Definition: plugin.h:104
#define vec_add2(V, P, N)
Add N elements to end of vector V, return pointer to new elements in P.
Definition: vec.h:561
#define hash_set_mem(h, key, value)
Definition: hash.h:274
u8 * format(u8 *s, const char *fmt,...)
Definition: format.c:419
#define vec_add(V, E, N)
Add N elements to end of vector V (no header, unspecified alignment)
Definition: vec.h:599
static int load_one_plugin(plugin_main_t *pm, plugin_info_t *pi, int from_early_init)
Definition: plugin.c:64
vlib_plugin_registration_t * reg
Definition: plugin.h:77
u8 is_disabled
Definition: plugin.h:84
#define vec_elt_at_index(v, i)
Get vector value at index i checking that i is in bounds.
#define clib_error_return(e, args...)
Definition: error.h:99
u8 * name
Definition: plugin.h:71
int vlib_plugin_early_init(vlib_main_t *vm)
Definition: plugin.c:349
#define hash_create_string(elts, value_bytes)
Definition: hash.h:652
uword * config_index_by_name
Definition: plugin.h:101
#define hash_unset_mem(h, key)
Definition: hash.h:280
#define v
Definition: acl.c:320
char * version
Definition: plugin.h:78
struct _unformat_input_t unformat_input_t
#define VLIB_CONFIG_FUNCTION(x, n,...)
Definition: init.h:119
plugin_info_t * plugin_info
Definition: plugin.h:92
#define hash_foreach_mem(key_var, value_var, h, body)
Definition: hash.h:437
#define UNFORMAT_END_OF_INPUT
Definition: format.h:143
svmdb_client_t * c
#define vec_free(V)
Free vector&#39;s memory (no header).
Definition: vec.h:340
#define clib_warning(format, args...)
Definition: error.h:59
clib_error_t * elf_read_file(elf_main_t *em, char *file_name)
Definition: elf.c:1329
void os_exit(int code)
Definition: unix-misc.c:182
char * vlib_plugin_app_version
Definition: plugin.c:27
static clib_error_t * config_one_plugin(vlib_main_t *vm, char *name, unformat_input_t *input)
Definition: plugin.c:406
#define VLIB_CLI_COMMAND(x,...)
Definition: cli.h:154
unsigned int u32
Definition: types.h:88
static void unformat_init(unformat_input_t *i, uword(*fill_buffer)(unformat_input_t *), void *fill_buffer_arg)
Definition: format.h:151
#define vec_delete(V, N, M)
Delete N elements starting at element M.
Definition: vec.h:785
static void * elf_get_section_contents(elf_main_t *em, uword section_index, uword elt_size)
Definition: elf.h:958
#define clib_error_report(e)
Definition: error.h:113
int vlib_load_new_plugins(plugin_main_t *pm, int from_early_init)
Definition: plugin.c:232
void * vlib_get_plugin_symbol(char *plugin_name, char *symbol_name)
Definition: plugin.c:31
static u8 ** split_plugin_path(plugin_main_t *pm)
Definition: plugin.c:196
u64 uword
Definition: types.h:112
void * handle
Definition: plugin.h:74
#define vec_len(v)
Number of elements in vector (rvalue-only, NULL tolerant)
unsigned char u8
Definition: types.h:56
uword unformat_vlib_cli_sub_input(unformat_input_t *i, va_list *args)
Definition: cli.c:152
#define vec_sort_with_function(vec, f)
Sort a vector using the supplied element comparison function.
Definition: vec.h:960
static void unformat_free(unformat_input_t *i)
Definition: format.h:161
#define hash_get_mem(h, key)
Definition: hash.h:268
u8 * format_unformat_error(u8 *s, va_list *va)
Definition: unformat.c:91
struct stat file_info
Definition: plugin.h:73
clib_error_t * elf_get_section_by_name(elf_main_t *em, char *section_name, elf_section_t **result)
Definition: elf.c:47
void vlib_cli_output(vlib_main_t *vm, char *fmt,...)
Definition: cli.c:680
static char * str_array_to_vec(char *array, int len)
Definition: plugin.c:45
u8 skip_version_check
Definition: plugin.h:86
plugin_main_t vlib_plugin_main
Definition: plugin.c:23
uword * plugin_by_name_hash
Definition: plugin.h:93
uword unformat(unformat_input_t *i, const char *fmt,...)
Definition: unformat.c:972
static clib_error_t * vlib_plugins_show_cmd_fn(vlib_main_t *vm, unformat_input_t *input, vlib_cli_command_t *cmd)
Definition: plugin.c:365
static uword unformat_check_input(unformat_input_t *i)
Definition: format.h:169