src/common/tracker.c

   1 /*
   2  * Copyright (C) 2019 Jonathan Rajotte <jonathan.rajotte-julien@efficios.com>
   3  * Copyright (C) 2020 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   4  *
   5  * SPDX-License-Identifier: LGPL-2.1-only
   6  *
   7  */
   8
   9 #include <lttng/domain.h>
  10 #include <lttng/lttng-error.h>
  11 #include <lttng/tracker.h>
  12
  13 #include <common/dynamic-array.h>
  14 #include <common/error.h>
  15 #include <common/hashtable/hashtable.h>
  16 #include <common/hashtable/utils.h>
  17 #include <common/tracker.h>
  18
  19 #include <stdbool.h>
  20
  21 struct process_attr_tracker_values_comm_header {
  22         uint32_t count;
  23 };
  24
  25 struct process_attr_tracker_value_comm {
  26         /* enum lttng_process_attr_value_type */
  27         int32_t type;
  28         union {
  29                 struct process_attr_integral_value_comm integral;
  30                 /* Includes the '\0' terminator. */
  31                 uint32_t name_len;
  32         } value;
  33 };
  34
  35 #define GET_INTEGRAL_COMM_VALUE(value_ptr, as_type)              \
  36         ((as_type)(is_signed(as_type) ? (value_ptr)->u._signed : \
  37                                         (value_ptr)->u._unsigned))
  38
  39 #define SET_INTEGRAL_COMM_VALUE(comm_value, value)                         \
  40         if (is_signed(typeof(value))) {                                    \
  41                 (comm_value)->u._signed =                                  \
  42                                 (typeof((comm_value)->u._signed)) value;   \
  43         } else {                                                           \
  44                 (comm_value)->u._unsigned =                                \
  45                                 (typeof((comm_value)->u._unsigned)) value; \
  46         }
  47
  48 static inline bool is_virtual_process_attr(enum lttng_process_attr process_attr)
  49 {
  50         return process_attr == LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID ||
  51                process_attr == LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID ||
  52                process_attr == LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID;
  53 }
  54
  55 static inline bool is_value_type_name(
  56                 enum lttng_process_attr_value_type value_type)
  57 {
  58         return value_type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME ||
  59                value_type == LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME;
  60 }
  61
  62 LTTNG_HIDDEN
  63 enum lttng_error_code process_attr_value_from_comm(
  64                 enum lttng_domain_type domain,
  65                 enum lttng_process_attr process_attr,
  66                 enum lttng_process_attr_value_type value_type,
  67                 const struct process_attr_integral_value_comm *integral_value,
  68                 const struct lttng_buffer_view *value_view,
  69                 struct process_attr_value **_value)
  70 {
  71         char *name = NULL;
  72         enum lttng_error_code ret = LTTNG_OK;
  73         struct process_attr_value *value = zmalloc(sizeof(*value));
  74
  75         if (!value) {
  76                 ret = LTTNG_ERR_NOMEM;
  77                 goto error;
  78         }
  79
  80         if (value_view && value_view->size > 0) {
  81                 if (value_view->data[value_view->size - 1] != '\0') {
  82                         ret = LTTNG_ERR_INVALID;
  83                         goto error;
  84                 }
  85                 name = strdup(value_view->data);
  86                 if (!name) {
  87                         ret = LTTNG_ERR_NOMEM;
  88                 }
  89         }
  90
  91         if (domain != LTTNG_DOMAIN_UST && domain != LTTNG_DOMAIN_KERNEL) {
  92                 ERR("Only the user space and kernel space domains may be specified to configure process attribute trackers");
  93                 ret = LTTNG_ERR_UNSUPPORTED_DOMAIN;
  94                 goto error;
  95         }
  96
  97         if (!is_virtual_process_attr(process_attr) &&
  98                         domain != LTTNG_DOMAIN_KERNEL) {
  99                 ERR("Non-virtual process attributes can only be used in the kernel domain");
 100                 ret = LTTNG_ERR_UNSUPPORTED_DOMAIN;
 101                 goto error;
 102         }
 103
 104         /* Only expect a payload for name value types. */
 105         if (is_value_type_name(value_type) && value_view->size == 0) {
 106                 ret = LTTNG_ERR_INVALID_PROTOCOL;
 107                 goto error;
 108         } else if (!is_value_type_name(value_type) && value_view->size != 0) {
 109                 ret = LTTNG_ERR_INVALID_PROTOCOL;
 110                 goto error;
 111         }
 112
 113         value->type = value_type;
 114         switch (process_attr) {
 115         case LTTNG_PROCESS_ATTR_PROCESS_ID:
 116         case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID:
 117                 if (value_type != LTTNG_PROCESS_ATTR_VALUE_TYPE_PID) {
 118                         ERR("Invalid value type used for process ID process attribute");
 119                         ret = LTTNG_ERR_INVALID;
 120                         goto error;
 121                 }
 122                 value->value.pid =
 123                                 GET_INTEGRAL_COMM_VALUE(integral_value, pid_t);
 124                 break;
 125         case LTTNG_PROCESS_ATTR_USER_ID:
 126         case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID:
 127                 switch (value_type) {
 128                 case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 129                         value->value.uid = GET_INTEGRAL_COMM_VALUE(
 130                                         integral_value, uid_t);
 131                         break;
 132                 case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 133                         if (!name) {
 134                                 ret = LTTNG_ERR_INVALID;
 135                                 goto error;
 136                         }
 137
 138                         value->value.user_name = name;
 139                         name = NULL;
 140                         break;
 141                 default:
 142                         ERR("Invalid value type used for user ID process attribute");
 143                         ret = LTTNG_ERR_INVALID;
 144                         goto error;
 145                 }
 146                 break;
 147         case LTTNG_PROCESS_ATTR_GROUP_ID:
 148         case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID:
 149                 switch (value_type) {
 150                 case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 151                         value->value.gid = GET_INTEGRAL_COMM_VALUE(
 152                                         integral_value, gid_t);
 153                         break;
 154                 case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 155                         if (!name) {
 156                                 ret = LTTNG_ERR_INVALID;
 157                                 goto error;
 158                         }
 159
 160                         value->value.group_name = name;
 161                         name = NULL;
 162                         break;
 163                 default:
 164                         ERR("Invalid value type used for group ID process attribute");
 165                         ret = LTTNG_ERR_INVALID;
 166                         goto error;
 167                 }
 168                 break;
 169         default:
 170                 ret = LTTNG_ERR_INVALID_PROTOCOL;
 171                 goto error;
 172         }
 173
 174         *_value = value;
 175         value = NULL;
 176         return LTTNG_OK;
 177 error:
 178         free(name);
 179         process_attr_value_destroy(value);
 180         return ret;
 181 }
 182
 183 LTTNG_HIDDEN
 184 const char *lttng_process_attr_to_string(enum lttng_process_attr process_attr)
 185 {
 186         switch (process_attr) {
 187         case LTTNG_PROCESS_ATTR_PROCESS_ID:
 188                 return "process ID";
 189         case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID:
 190                 return "virtual process ID";
 191         case LTTNG_PROCESS_ATTR_USER_ID:
 192                 return "user ID";
 193         case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID:
 194                 return "virtual user ID";
 195         case LTTNG_PROCESS_ATTR_GROUP_ID:
 196                 return "group ID";
 197         case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID:
 198                 return "virtual group ID";
 199         default:
 200                 return "unknown process attribute";
 201         }
 202 }
 203
 204 static void process_attr_tracker_value_destructor(void *ptr)
 205 {
 206         struct process_attr_value *value = (typeof(value)) ptr;
 207
 208         process_attr_value_destroy(value);
 209 }
 210
 211 LTTNG_HIDDEN
 212 struct lttng_process_attr_values *lttng_process_attr_values_create(void)
 213 {
 214         struct lttng_process_attr_values *values = zmalloc(sizeof(*values));
 215
 216         if (!values) {
 217                 goto end;
 218         }
 219
 220         lttng_dynamic_pointer_array_init(
 221                         &values->array, process_attr_tracker_value_destructor);
 222 end:
 223         return values;
 224 }
 225
 226 LTTNG_HIDDEN
 227 unsigned int _lttng_process_attr_values_get_count(
 228                 const struct lttng_process_attr_values *values)
 229 {
 230         return (unsigned int) lttng_dynamic_pointer_array_get_count(
 231                         &values->array);
 232 }
 233
 234 LTTNG_HIDDEN
 235 const struct process_attr_value *lttng_process_attr_tracker_values_get_at_index(
 236                 const struct lttng_process_attr_values *values,
 237                 unsigned int index)
 238 {
 239         return lttng_dynamic_pointer_array_get_pointer(&values->array, index);
 240 }
 241
 242 static
 243 int process_attr_tracker_value_serialize(const struct process_attr_value *value,
 244                 struct lttng_dynamic_buffer *buffer)
 245 {
 246         int ret;
 247         struct process_attr_tracker_value_comm value_comm = {
 248                         .type = (int32_t) value->type,
 249         };
 250         const char *name = NULL;
 251
 252         switch (value->type) {
 253         case LTTNG_PROCESS_ATTR_VALUE_TYPE_PID:
 254                 SET_INTEGRAL_COMM_VALUE(
 255                                 &value_comm.value.integral, value->value.pid);
 256                 break;
 257         case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 258                 SET_INTEGRAL_COMM_VALUE(
 259                                 &value_comm.value.integral, value->value.uid);
 260                 break;
 261         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 262                 SET_INTEGRAL_COMM_VALUE(
 263                                 &value_comm.value.integral, value->value.gid);
 264                 break;
 265         case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 266                 name = value->value.user_name;
 267                 break;
 268         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 269                 name = value->value.group_name;
 270                 break;
 271         default:
 272                 abort();
 273         }
 274
 275         if (name) {
 276                 value_comm.value.name_len = strlen(name) + 1;
 277         }
 278
 279         ret = lttng_dynamic_buffer_append(
 280                         buffer, &value_comm, sizeof(value_comm));
 281         if (ret) {
 282                 goto end;
 283         }
 284
 285         if (name) {
 286                 ret = lttng_dynamic_buffer_append(
 287                                 buffer, name, value_comm.value.name_len);
 288         }
 289 end:
 290         return ret;
 291 }
 292
 293 LTTNG_HIDDEN
 294 int lttng_process_attr_values_serialize(
 295                 const struct lttng_process_attr_values *values,
 296                 struct lttng_dynamic_buffer *buffer)
 297 {
 298         int ret;
 299         unsigned int count, i;
 300         struct process_attr_tracker_values_comm_header header = {};
 301
 302         count = _lttng_process_attr_values_get_count(values);
 303         header.count = (uint32_t) count;
 304
 305         ret = lttng_dynamic_buffer_append(buffer, &header, sizeof(header));
 306         if (ret) {
 307                 goto end;
 308         }
 309
 310         for (i = 0; i < count; i++) {
 311                 const struct process_attr_value *value =
 312                                 lttng_process_attr_tracker_values_get_at_index(
 313                                                 values, i);
 314
 315                 ret = process_attr_tracker_value_serialize(value, buffer);
 316                 if (ret) {
 317                         goto end;
 318                 }
 319         }
 320 end:
 321         return ret;
 322 }
 323
 324 LTTNG_HIDDEN
 325 ssize_t lttng_process_attr_values_create_from_buffer(
 326                 enum lttng_domain_type domain,
 327                 enum lttng_process_attr process_attr,
 328                 const struct lttng_buffer_view *buffer_view,
 329                 struct lttng_process_attr_values **_values)
 330 {
 331         ssize_t offset;
 332         unsigned int i;
 333         struct lttng_process_attr_values *values;
 334         struct lttng_buffer_view header_view;
 335         const struct process_attr_tracker_values_comm_header *header;
 336
 337         values = lttng_process_attr_values_create();
 338         if (!values) {
 339                 goto error;
 340         }
 341
 342         header_view = lttng_buffer_view_from_view(
 343                         buffer_view, 0, sizeof(*header));
 344         if (!header_view.data) {
 345                 goto error;
 346         }
 347         offset = header_view.size;
 348         header = (typeof(header)) header_view.data;
 349
 350         /*
 351          * Check that the number of values is not absurdly large with respect to
 352          * the received buffer's size.
 353          */
 354         if (buffer_view->size <
 355                         header->count * sizeof(struct process_attr_tracker_value_comm)) {
 356                 goto error;
 357         }
 358         for (i = 0; i < (unsigned int) header->count; i++) {
 359                 int ret;
 360                 enum lttng_error_code ret_code;
 361                 const struct process_attr_tracker_value_comm *value_comm;
 362                 struct process_attr_value *value;
 363                 enum lttng_process_attr_value_type type;
 364                 struct lttng_buffer_view value_view;
 365                 struct lttng_buffer_view value_name_view = {};
 366
 367                 value_view = lttng_buffer_view_from_view(
 368                                 buffer_view, offset, sizeof(*value_comm));
 369                 if (!value_view.data) {
 370                         goto error;
 371                 }
 372
 373                 offset += value_view.size;
 374                 value_comm = (typeof(value_comm)) value_view.data;
 375                 type = (typeof(type)) value_comm->type;
 376
 377                 if (is_value_type_name(type)) {
 378                         value_name_view = lttng_buffer_view_from_view(
 379                                         buffer_view, offset,
 380                                         value_comm->value.name_len);
 381                         offset += value_name_view.size;
 382                 }
 383                 ret_code = process_attr_value_from_comm(domain, process_attr,
 384                                 type, &value_comm->value.integral,
 385                                 &value_name_view, &value);
 386                 if (ret_code != LTTNG_OK) {
 387                         goto error;
 388                 }
 389
 390                 ret = lttng_dynamic_pointer_array_add_pointer(
 391                                 &values->array, value);
 392                 if (ret) {
 393                         process_attr_value_destroy(value);
 394                         goto error;
 395                 }
 396         }
 397
 398         *_values = values;
 399         return offset;
 400 error:
 401         lttng_process_attr_values_destroy(values);
 402         return -1;
 403 }
 404
 405 LTTNG_HIDDEN
 406 void lttng_process_attr_values_destroy(struct lttng_process_attr_values *values)
 407 {
 408         if (!values) {
 409                 return;
 410         }
 411         lttng_dynamic_pointer_array_reset(&values->array);
 412         free(values);
 413 }
 414
 415 LTTNG_HIDDEN
 416 struct process_attr_value *process_attr_value_copy(
 417                 const struct process_attr_value *value)
 418 {
 419         struct process_attr_value *new_value = NULL;
 420
 421         if (!value) {
 422                 goto end;
 423         }
 424
 425         new_value = zmalloc(sizeof(*new_value));
 426         if (!new_value) {
 427                 goto end;
 428         }
 429         if (is_value_type_name(value->type)) {
 430                 const char *src =
 431                                 value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME ?
 432                                                 value->value.user_name :
 433                                                 value->value.group_name;
 434                 char **dst = value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME ?
 435                                              &new_value->value.user_name :
 436                                              &new_value->value.group_name;
 437
 438                 new_value->type = value->type;
 439                 *dst = strdup(src);
 440                 if (!*dst) {
 441                         goto error;
 442                 }
 443         } else {
 444                 *new_value = *value;
 445         }
 446 end:
 447         return new_value;
 448 error:
 449         free(new_value);
 450         return NULL;
 451 }
 452
 453 LTTNG_HIDDEN
 454 unsigned long process_attr_value_hash(const struct process_attr_value *a)
 455 {
 456         unsigned long hash = hash_key_ulong((void *) a->type, lttng_ht_seed);
 457
 458         switch (a->type) {
 459         case LTTNG_PROCESS_ATTR_VALUE_TYPE_PID:
 460                 hash ^= hash_key_ulong((void *) (unsigned long) a->value.pid,
 461                                 lttng_ht_seed);
 462                 break;
 463         case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 464                 hash ^= hash_key_ulong((void *) (unsigned long) a->value.uid,
 465                                 lttng_ht_seed);
 466                 break;
 467         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 468                 hash ^= hash_key_ulong((void *) (unsigned long) a->value.gid,
 469                                 lttng_ht_seed);
 470                 break;
 471         case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 472                 hash ^= hash_key_str(a->value.user_name, lttng_ht_seed);
 473                 break;
 474         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 475                 hash ^= hash_key_str(a->value.group_name, lttng_ht_seed);
 476                 break;
 477         default:
 478                 abort();
 479         }
 480
 481         return hash;
 482 }
 483
 484 LTTNG_HIDDEN
 485 bool process_attr_tracker_value_equal(const struct process_attr_value *a,
 486                 const struct process_attr_value *b)
 487 {
 488         if (a->type != b->type) {
 489                 return false;
 490         }
 491         switch (a->type) {
 492         case LTTNG_PROCESS_ATTR_VALUE_TYPE_PID:
 493                 return a->value.pid == b->value.pid;
 494         case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 495                 return a->value.uid == b->value.uid;
 496         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 497                 return a->value.gid == b->value.gid;
 498         case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 499                 return !strcmp(a->value.user_name, b->value.user_name);
 500         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 501                 return !strcmp(a->value.group_name, b->value.group_name);
 502         default:
 503                 abort();
 504         }
 505 }
 506
 507 LTTNG_HIDDEN
 508 void process_attr_value_destroy(struct process_attr_value *value)
 509 {
 510         if (!value) {
 511                 return;
 512         }
 513         if (is_value_type_name(value->type)) {
 514                 free(value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME ?
 515                                                 value->value.user_name :
 516                                                 value->value.group_name);
 517         }
 518         free(value);
 519 }