FD.io VPP  v18.11-rc0-18-g2a3fb1a
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 
98  reg->default_disabled = 1;
99 
100  p = hash_get_mem (pm->config_index_by_name, pi->name);
101  if (p)
102  {
103  pc = vec_elt_at_index (pm->configs, p[0]);
104  if (pc->is_disabled)
105  {
106  clib_warning ("Plugin disabled: %s", pi->name);
107  goto error;
108  }
109  if (reg->default_disabled && pc->is_enabled == 0)
110  {
111  clib_warning ("Plugin disabled (default): %s", pi->name);
112  goto error;
113  }
114  }
115  else if (reg->default_disabled)
116  {
117  clib_warning ("Plugin disabled (default): %s", pi->name);
118  goto error;
119  }
120 
121  version_required = str_array_to_vec ((char *) &reg->version_required,
122  sizeof (reg->version_required));
123 
124  if ((strlen (version_required) > 0) &&
125  (strncmp (vlib_plugin_app_version, version_required,
126  strlen (version_required))))
127  {
128  clib_warning ("Plugin %s version mismatch: %s != %s",
129  pi->name, vlib_plugin_app_version, reg->version_required);
130  if (!(pc && pc->skip_version_check == 1))
131  {
132  vec_free (version_required);
133  goto error;
134  }
135  }
136 
137  vec_free (version_required);
138  vec_free (data);
139  elf_main_free (&em);
140 
141  handle = dlopen ((char *) pi->filename, RTLD_LAZY);
142 
143  if (handle == 0)
144  {
145  clib_warning ("%s", dlerror ());
146  clib_warning ("Failed to load plugin '%s'", pi->name);
147  goto error;
148  }
149 
150  pi->handle = handle;
151 
152  reg = dlsym (pi->handle, "vlib_plugin_registration");
153 
154  if (reg == 0)
155  {
156  /* This should never happen unless somebody chagnes registration macro */
157  clib_warning ("Missing plugin registration in plugin '%s'", pi->name);
158  dlclose (pi->handle);
159  goto error;
160  }
161 
162  pi->reg = reg;
163  pi->version = str_array_to_vec ((char *) &reg->version,
164  sizeof (reg->version));
165 
166  if (reg->early_init)
167  {
168  clib_error_t *(*ei) (vlib_main_t *);
169  void *h;
170 
171  h = dlsym (pi->handle, reg->early_init);
172  if (h)
173  {
174  ei = h;
175  error = (*ei) (pm->vlib_main);
176  if (error)
177  {
178  clib_error_report (error);
179  dlclose (pi->handle);
180  goto error;
181  }
182  }
183  else
184  clib_warning ("Plugin %s: early init function %s set but not found",
185  (char *) pi->name, reg->early_init);
186  }
187 
188  if (reg->description)
189  clib_warning ("Loaded plugin: %s (%s)", pi->name, reg->description);
190  else
191  clib_warning ("Loaded plugin: %s", pi->name);
192 
193  return 0;
194 error:
195  vec_free (data);
196  elf_main_free (&em);
197  return -1;
198 }
199 
200 static u8 **
202 {
203  int i;
204  u8 **rv = 0;
205  u8 *path = pm->plugin_path;
206  u8 *this = 0;
207 
208  for (i = 0; i < vec_len (pm->plugin_path); i++)
209  {
210  if (path[i] != ':')
211  {
212  vec_add1 (this, path[i]);
213  continue;
214  }
215  vec_add1 (this, 0);
216  vec_add1 (rv, this);
217  this = 0;
218  }
219  if (this)
220  {
221  vec_add1 (this, 0);
222  vec_add1 (rv, this);
223  }
224  return rv;
225 }
226 
227 static int
228 plugin_name_sort_cmp (void *a1, void *a2)
229 {
230  plugin_info_t *p1 = a1;
231  plugin_info_t *p2 = a2;
232 
233  return strcmp ((char *) p1->name, (char *) p2->name);
234 }
235 
236 int
237 vlib_load_new_plugins (plugin_main_t * pm, int from_early_init)
238 {
239  DIR *dp;
240  struct dirent *entry;
241  struct stat statb;
242  uword *p;
243  plugin_info_t *pi;
244  u8 **plugin_path;
245  u32 *load_fail_indices = 0;
246  int i;
247 
248  plugin_path = split_plugin_path (pm);
249 
250  for (i = 0; i < vec_len (plugin_path); i++)
251  {
252  dp = opendir ((char *) plugin_path[i]);
253 
254  if (dp == 0)
255  continue;
256 
257  while ((entry = readdir (dp)))
258  {
259  u8 *plugin_name;
260  u8 *filename;
261 
262  if (pm->plugin_name_filter)
263  {
264  int j;
265  for (j = 0; j < vec_len (pm->plugin_name_filter); j++)
266  if (entry->d_name[j] != pm->plugin_name_filter[j])
267  goto next;
268  }
269 
270  filename = format (0, "%s/%s%c", plugin_path[i], entry->d_name, 0);
271 
272  /* Only accept .so */
273  char *ext = strrchr ((const char *) filename, '.');
274  /* unreadable */
275  if (!ext || (strcmp (ext, ".so") != 0) ||
276  stat ((char *) filename, &statb) < 0)
277  {
278  ignore:
279  vec_free (filename);
280  continue;
281  }
282 
283  /* a dir or other things which aren't plugins */
284  if (!S_ISREG (statb.st_mode))
285  goto ignore;
286 
287  plugin_name = format (0, "%s%c", entry->d_name, 0);
288  /* Have we seen this plugin already? */
289  p = hash_get_mem (pm->plugin_by_name_hash, plugin_name);
290  if (p == 0)
291  {
292  /* No, add it to the plugin vector */
293  vec_add2 (pm->plugin_info, pi, 1);
294  pi->name = plugin_name;
295  pi->filename = filename;
296  pi->file_info = statb;
297  hash_set_mem (pm->plugin_by_name_hash, plugin_name,
298  pi - pm->plugin_info);
299  }
300  next:
301  ;
302  }
303  closedir (dp);
304  vec_free (plugin_path[i]);
305  }
306  vec_free (plugin_path);
307 
308 
309  /*
310  * Sort the plugins by name. This is important.
311  * API traces contain absolute message numbers.
312  * Loading plugins in directory (vs. alphabetical) order
313  * makes trace replay incredibly fragile.
314  */
316 
317  /*
318  * Attempt to load the plugins
319  */
320  for (i = 0; i < vec_len (pm->plugin_info); i++)
321  {
322  pi = vec_elt_at_index (pm->plugin_info, i);
323 
324  if (load_one_plugin (pm, pi, from_early_init))
325  {
326  /* Make a note of any which fail to load */
327  vec_add1 (load_fail_indices, i);
329  vec_free (pi->name);
330  vec_free (pi->filename);
331  }
332  }
333 
334  /* Remove plugin info vector elements corresponding to load failures */
335  if (vec_len (load_fail_indices) > 0)
336  {
337  for (i = vec_len (load_fail_indices) - 1; i >= 0; i--)
338  vec_delete (pm->plugin_info, 1, load_fail_indices[i]);
339  vec_free (load_fail_indices);
340  }
341 
342  /* Recreate the plugin name hash */
343  for (i = 0; i < vec_len (pm->plugin_info); i++)
344  {
345  pi = vec_elt_at_index (pm->plugin_info, i);
347  hash_set_mem (pm->plugin_by_name_hash, pi->name, pi - pm->plugin_info);
348  }
349 
350  return 0;
351 }
352 
353 int
355 {
357 
358  if (pm->plugin_path == 0)
359  pm->plugin_path = format (0, "%s%c", vlib_plugin_path, 0);
360 
361  clib_warning ("plugin path %s", pm->plugin_path);
362 
363  pm->plugin_by_name_hash = hash_create_string (0, sizeof (uword));
364  pm->vlib_main = vm;
365 
366  return vlib_load_new_plugins (pm, 1 /* from_early_init */ );
367 }
368 
369 u8 *
371 {
373  return (pm->vat_plugin_path);
374 }
375 
376 u8 *
378 {
380  return (pm->vat_plugin_name_filter);
381 }
382 
383 static clib_error_t *
385  unformat_input_t * input, vlib_cli_command_t * cmd)
386 {
388  u8 *s = 0;
389  u8 *key = 0;
390  uword value = 0;
391  int index = 1;
392  plugin_info_t *pi;
393 
394  s = format (s, " Plugin path is: %s\n\n", pm->plugin_path);
395  s = format (s, " %-41s%-33s%s\n", "Plugin", "Version", "Description");
396 
397  /* *INDENT-OFF* */
398  hash_foreach_mem (key, value, pm->plugin_by_name_hash,
399  {
400  if (key != 0)
401  {
402  pi = vec_elt_at_index (pm->plugin_info, value);
403  s = format (s, "%3d. %-40s %-32s %s\n", index, key, pi->version,
404  pi->reg->description ? pi->reg->description : "");
405  index++;
406  }
407  });
408  /* *INDENT-ON* */
409 
410  vlib_cli_output (vm, "%v", s);
411  vec_free (s);
412  return 0;
413 }
414 
415 /* *INDENT-OFF* */
416 VLIB_CLI_COMMAND (plugins_show_cmd, static) =
417 {
418  .path = "show plugins",
419  .short_help = "show loaded plugins",
420  .function = vlib_plugins_show_cmd_fn,
421 };
422 /* *INDENT-ON* */
423 
424 static clib_error_t *
426 {
428  plugin_config_t *pc;
429  clib_error_t *error = 0;
430  uword *p;
431  int is_enable = 0;
432  int is_disable = 0;
433  int skip_version_check = 0;
434 
435  if (pm->config_index_by_name == 0)
436  pm->config_index_by_name = hash_create_string (0, sizeof (uword));
437 
438  p = hash_get_mem (pm->config_index_by_name, name);
439 
440  if (p)
441  {
442  error = clib_error_return (0, "plugin '%s' already configured", name);
443  goto done;
444  }
445 
447  {
448  if (unformat (input, "enable"))
449  is_enable = 1;
450  else if (unformat (input, "disable"))
451  is_disable = 1;
452  else if (unformat (input, "skip-version-check"))
453  skip_version_check = 1;
454  else
455  {
456  error = clib_error_return (0, "unknown input '%U'",
457  format_unformat_error, input);
458  goto done;
459  }
460  }
461 
462  if (is_enable && is_disable)
463  {
464  error = clib_error_return (0, "please specify either enable or disable"
465  " for plugin '%s'", name);
466  goto done;
467  }
468 
469  vec_add2 (pm->configs, pc, 1);
470  hash_set_mem (pm->config_index_by_name, name, pc - pm->configs);
471  pc->is_enabled = is_enable;
472  pc->is_disabled = is_disable;
473  pc->skip_version_check = skip_version_check;
474  pc->name = name;
475 
476 done:
477  return error;
478 }
479 
480 clib_error_t *
482 {
484  clib_error_t *error = 0;
485  unformat_input_t in;
486 
487  unformat_init (&in, 0, 0);
488 
490  {
491  u8 *s, *v;
492  if (unformat (input, "%s %v", &s, &v))
493  {
494  if (strncmp ((const char *) s, "plugins", 8) == 0)
495  {
496  if (vec_len (in.buffer) > 0)
497  vec_add1 (in.buffer, ' ');
498  vec_add (in.buffer, v, vec_len (v));
499  }
500  }
501  else
502  {
503  error = clib_error_return (0, "unknown input '%U'",
504  format_unformat_error, input);
505  goto done;
506  }
507 
508  vec_free (v);
509  vec_free (s);
510  }
511 done:
512  input = &in;
514  {
515  unformat_input_t sub_input;
516  u8 *s = 0;
517  if (unformat (input, "path %s", &s))
518  pm->plugin_path = s;
519  else if (unformat (input, "name-filter %s", &s))
520  pm->plugin_name_filter = s;
521  else if (unformat (input, "vat-path %s", &s))
522  pm->vat_plugin_path = s;
523  else if (unformat (input, "vat-name-filter %s", &s))
524  pm->vat_plugin_name_filter = s;
525  else if (unformat (input, "plugin default %U",
526  unformat_vlib_cli_sub_input, &sub_input))
527  {
529  unformat (&sub_input, "disable") ? 1 : 0;
530  unformat_free (&sub_input);
531  }
532  else if (unformat (input, "plugin %s %U", &s,
533  unformat_vlib_cli_sub_input, &sub_input))
534  {
535  error = config_one_plugin (vm, (char *) s, &sub_input);
536  unformat_free (&sub_input);
537  if (error)
538  goto done2;
539  }
540  else
541  {
542  error = clib_error_return (0, "unknown input '%U'",
543  format_unformat_error, input);
544  {
545  vec_free (s);
546  goto done2;
547  }
548  }
549  }
550 
551 done2:
552  unformat_free (&in);
553  return error;
554 }
555 
556 /* discard whole 'plugins' section, as it is already consumed prior to
557  plugin load */
558 static clib_error_t *
560 {
561  u8 *junk;
562 
564  {
565  if (unformat (input, "%s", &junk))
566  {
567  vec_free (junk);
568  return 0;
569  }
570  else
571  return clib_error_return (0, "unknown input '%U'",
572  format_unformat_error, input);
573  }
574  return 0;
575 }
576 
578 
579 /*
580  * fd.io coding-style-patch-verification: ON
581  *
582  * Local Variables:
583  * eval: (c-set-style "gnu")
584  * End:
585  */
u8 * vlib_get_vat_plugin_name_filter(void)
Definition: plugin.c:377
vlib_main_t * vlib_main
Definition: plugin.h:107
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
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:559
char * name
Definition: plugin.h:83
u8 * vat_plugin_name_filter
Definition: plugin.h:99
static int plugin_name_sort_cmp(void *a1, void *a2)
Definition: plugin.c:228
u32 index
Definition: elf.h:857
u8 * vlib_get_vat_plugin_path(void)
Definition: plugin.c:370
#define vec_add1(V, E)
Add 1 element to end of vector (unspecified alignment).
Definition: vec.h:523
clib_error_t * vlib_plugin_config(vlib_main_t *vm, unformat_input_t *input)
Definition: plugin.c:481
#define vec_add2(V, P, N)
Add N elements to end of vector V, return pointer to new elements in P.
Definition: vec.h:562
int i
#define hash_set_mem(h, key, value)
Definition: hash.h:275
u8 * format(u8 *s, const char *fmt,...)
Definition: format.c:419
unsigned char u8
Definition: types.h:56
uword * config_index_by_name
Definition: plugin.h:104
#define vec_add(V, E, N)
Add N elements to end of vector V (no header, unspecified alignment)
Definition: vec.h:600
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
unsigned int u32
Definition: types.h:88
int vlib_plugin_early_init(vlib_main_t *vm)
Definition: plugin.c:354
#define hash_create_string(elts, value_bytes)
Definition: hash.h:690
#define hash_unset_mem(h, key)
Definition: hash.h:291
#define v
Definition: acl.c:491
char * version
Definition: plugin.h:78
struct _unformat_input_t unformat_input_t
#define VLIB_CONFIG_FUNCTION(x, n,...)
Definition: init.h:164
plugin_info_t * plugin_info
Definition: plugin.h:92
#define hash_foreach_mem(key_var, value_var, h, body)
Definition: hash.h:461
#define UNFORMAT_END_OF_INPUT
Definition: format.h:144
svmdb_client_t * c
vlib_main_t * vm
Definition: buffer.c:294
#define vec_free(V)
Free vector&#39;s memory (no header).
Definition: vec.h:339
#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
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:425
#define VLIB_CLI_COMMAND(x,...)
Definition: cli.h:154
u8 * vat_plugin_path
Definition: plugin.h:98
static void unformat_init(unformat_input_t *i, uword(*fill_buffer)(unformat_input_t *), void *fill_buffer_arg)
Definition: format.h:152
#define vec_delete(V, N, M)
Delete N elements starting at element M.
Definition: vec.h:786
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:237
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:201
void * handle
Definition: plugin.h:74
#define vec_len(v)
Number of elements in vector (rvalue-only, NULL tolerant)
uword unformat_vlib_cli_sub_input(unformat_input_t *i, va_list *args)
Definition: cli.c:153
u64 uword
Definition: types.h:112
#define vec_sort_with_function(vec, f)
Sort a vector using the supplied element comparison function.
Definition: vec.h:982
static void unformat_free(unformat_input_t *i)
Definition: format.h:162
#define hash_get_mem(h, key)
Definition: hash.h:269
u8 * format_unformat_error(u8 *s, va_list *va)
Definition: unformat.c:91
plugin_config_t * configs
Definition: plugin.h:103
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:681
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
u8 plugins_default_disable
Definition: plugin.h:100
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:384
static uword unformat_check_input(unformat_input_t *i)
Definition: format.h:170