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         free(name);
 177         return LTTNG_OK;
 178 error:
 179         free(name);
 180         process_attr_value_destroy(value);
 181         return ret;
 182 }
 183
 184 LTTNG_HIDDEN
 185 const char *lttng_process_attr_to_string(enum lttng_process_attr process_attr)
 186 {
 187         switch (process_attr) {
 188         case LTTNG_PROCESS_ATTR_PROCESS_ID:
 189                 return "process ID";
 190         case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID:
 191                 return "virtual process ID";
 192         case LTTNG_PROCESS_ATTR_USER_ID:
 193                 return "user ID";
 194         case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID:
 195                 return "virtual user ID";
 196         case LTTNG_PROCESS_ATTR_GROUP_ID:
 197                 return "group ID";
 198         case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID:
 199                 return "virtual group ID";
 200         default:
 201                 return "unknown process attribute";
 202         }
 203 }
 204
 205 static void process_attr_tracker_value_destructor(void *ptr)
 206 {
 207         struct process_attr_value *value = (typeof(value)) ptr;
 208
 209         process_attr_value_destroy(value);
 210 }
 211
 212 LTTNG_HIDDEN
 213 struct lttng_process_attr_values *lttng_process_attr_values_create(void)
 214 {
 215         struct lttng_process_attr_values *values = zmalloc(sizeof(*values));
 216
 217         if (!values) {
 218                 goto end;
 219         }
 220
 221         lttng_dynamic_pointer_array_init(
 222                         &values->array, process_attr_tracker_value_destructor);
 223 end:
 224         return values;
 225 }
 226
 227 LTTNG_HIDDEN
 228 unsigned int _lttng_process_attr_values_get_count(
 229                 const struct lttng_process_attr_values *values)
 230 {
 231         return (unsigned int) lttng_dynamic_pointer_array_get_count(
 232                         &values->array);
 233 }
 234
 235 LTTNG_HIDDEN
 236 const struct process_attr_value *lttng_process_attr_tracker_values_get_at_index(
 237                 const struct lttng_process_attr_values *values,
 238                 unsigned int index)
 239 {
 240         return lttng_dynamic_pointer_array_get_pointer(&values->array, index);
 241 }
 242
 243 static
 244 int process_attr_tracker_value_serialize(const struct process_attr_value *value,
 245                 struct lttng_dynamic_buffer *buffer)
 246 {
 247         int ret;
 248         struct process_attr_tracker_value_comm value_comm = {
 249                         .type = (int32_t) value->type,
 250         };
 251         const char *name = NULL;
 252
 253         switch (value->type) {
 254         case LTTNG_PROCESS_ATTR_VALUE_TYPE_PID:
 255                 SET_INTEGRAL_COMM_VALUE(
 256                                 &value_comm.value.integral, value->value.pid);
 257                 break;
 258         case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 259                 SET_INTEGRAL_COMM_VALUE(
 260                                 &value_comm.value.integral, value->value.uid);
 261                 break;
 262         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 263                 SET_INTEGRAL_COMM_VALUE(
 264                                 &value_comm.value.integral, value->value.gid);
 265                 break;
 266         case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 267                 name = value->value.user_name;
 268                 break;
 269         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 270                 name = value->value.group_name;
 271                 break;
 272         default:
 273                 abort();
 274         }
 275
 276         if (name) {
 277                 value_comm.value.name_len = strlen(name) + 1;
 278         }
 279
 280         ret = lttng_dynamic_buffer_append(
 281                         buffer, &value_comm, sizeof(value_comm));
 282         if (ret) {
 283                 goto end;
 284         }
 285
 286         if (name) {
 287                 ret = lttng_dynamic_buffer_append(
 288                                 buffer, name, value_comm.value.name_len);
 289         }
 290 end:
 291         return ret;
 292 }
 293
 294 LTTNG_HIDDEN
 295 int lttng_process_attr_values_serialize(
 296                 const struct lttng_process_attr_values *values,
 297                 struct lttng_dynamic_buffer *buffer)
 298 {
 299         int ret;
 300         unsigned int count, i;
 301         struct process_attr_tracker_values_comm_header header = {};
 302
 303         count = _lttng_process_attr_values_get_count(values);
 304         header.count = (uint32_t) count;
 305
 306         ret = lttng_dynamic_buffer_append(buffer, &header, sizeof(header));
 307         if (ret) {
 308                 goto end;
 309         }
 310
 311         for (i = 0; i < count; i++) {
 312                 const struct process_attr_value *value =
 313                                 lttng_process_attr_tracker_values_get_at_index(
 314                                                 values, i);
 315
 316                 ret = process_attr_tracker_value_serialize(value, buffer);
 317                 if (ret) {
 318                         goto end;
 319                 }
 320         }
 321 end:
 322         return ret;
 323 }
 324
 325 LTTNG_HIDDEN
 326 ssize_t lttng_process_attr_values_create_from_buffer(
 327                 enum lttng_domain_type domain,
 328                 enum lttng_process_attr process_attr,
 329                 const struct lttng_buffer_view *buffer_view,
 330                 struct lttng_process_attr_values **_values)
 331 {
 332         ssize_t offset;
 333         unsigned int i;
 334         struct lttng_process_attr_values *values;
 335         struct lttng_buffer_view header_view;
 336         const struct process_attr_tracker_values_comm_header *header;
 337
 338         values = lttng_process_attr_values_create();
 339         if (!values) {
 340                 goto error;
 341         }
 342
 343         header_view = lttng_buffer_view_from_view(
 344                         buffer_view, 0, sizeof(*header));
 345         if (!header_view.data) {
 346                 goto error;
 347         }
 348         offset = header_view.size;
 349         header = (typeof(header)) header_view.data;
 350
 351         /*
 352          * Check that the number of values is not absurdly large with respect to
 353          * the received buffer's size.
 354          */
 355         if (buffer_view->size <
 356                         header->count * sizeof(struct process_attr_tracker_value_comm)) {
 357                 goto error;
 358         }
 359         for (i = 0; i < (unsigned int) header->count; i++) {
 360                 int ret;
 361                 enum lttng_error_code ret_code;
 362                 const struct process_attr_tracker_value_comm *value_comm;
 363                 struct process_attr_value *value;
 364                 enum lttng_process_attr_value_type type;
 365                 struct lttng_buffer_view value_view;
 366                 struct lttng_buffer_view value_name_view = {};
 367
 368                 value_view = lttng_buffer_view_from_view(
 369                                 buffer_view, offset, sizeof(*value_comm));
 370                 if (!value_view.data) {
 371                         goto error;
 372                 }
 373
 374                 offset += value_view.size;
 375                 value_comm = (typeof(value_comm)) value_view.data;
 376                 type = (typeof(type)) value_comm->type;
 377
 378                 if (is_value_type_name(type)) {
 379                         value_name_view = lttng_buffer_view_from_view(
 380                                         buffer_view, offset,
 381                                         value_comm->value.name_len);
 382                         offset += value_name_view.size;
 383                 }
 384                 ret_code = process_attr_value_from_comm(domain, process_attr,
 385                                 type, &value_comm->value.integral,
 386                                 &value_name_view, &value);
 387                 if (ret_code != LTTNG_OK) {
 388                         goto error;
 389                 }
 390
 391                 ret = lttng_dynamic_pointer_array_add_pointer(
 392                                 &values->array, value);
 393                 if (ret) {
 394                         process_attr_value_destroy(value);
 395                         goto error;
 396                 }
 397         }
 398
 399         *_values = values;
 400         return offset;
 401 error:
 402         lttng_process_attr_values_destroy(values);
 403         return -1;
 404 }
 405
 406 LTTNG_HIDDEN
 407 void lttng_process_attr_values_destroy(struct lttng_process_attr_values *values)
 408 {
 409         if (!values) {
 410                 return;
 411         }
 412         lttng_dynamic_pointer_array_reset(&values->array);
 413         free(values);
 414 }
 415
 416 LTTNG_HIDDEN
 417 struct process_attr_value *process_attr_value_copy(
 418                 const struct process_attr_value *value)
 419 {
 420         struct process_attr_value *new_value = NULL;
 421
 422         if (!value) {
 423                 goto end;
 424         }
 425
 426         new_value = zmalloc(sizeof(*new_value));
 427         if (!new_value) {
 428                 goto end;
 429         }
 430         if (is_value_type_name(value->type)) {
 431                 const char *src =
 432                                 value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME ?
 433                                                 value->value.user_name :
 434                                                 value->value.group_name;
 435                 char **dst = value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME ?
 436                                              &new_value->value.user_name :
 437                                              &new_value->value.group_name;
 438
 439                 new_value->type = value->type;
 440                 *dst = strdup(src);
 441                 if (!*dst) {
 442                         goto error;
 443                 }
 444         } else {
 445                 *new_value = *value;
 446         }
 447 end:
 448         return new_value;
 449 error:
 450         free(new_value);
 451         return NULL;
 452 }
 453
 454 LTTNG_HIDDEN
 455 unsigned long process_attr_value_hash(const struct process_attr_value *a)
 456 {
 457         unsigned long hash = hash_key_ulong((void *) a->type, lttng_ht_seed);
 458
 459         switch (a->type) {
 460         case LTTNG_PROCESS_ATTR_VALUE_TYPE_PID:
 461                 hash ^= hash_key_ulong((void *) (unsigned long) a->value.pid,
 462                                 lttng_ht_seed);
 463                 break;
 464         case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 465                 hash ^= hash_key_ulong((void *) (unsigned long) a->value.uid,
 466                                 lttng_ht_seed);
 467                 break;
 468         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 469                 hash ^= hash_key_ulong((void *) (unsigned long) a->value.gid,
 470                                 lttng_ht_seed);
 471                 break;
 472         case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 473                 hash ^= hash_key_str(a->value.user_name, lttng_ht_seed);
 474                 break;
 475         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 476                 hash ^= hash_key_str(a->value.group_name, lttng_ht_seed);
 477                 break;
 478         default:
 479                 abort();
 480         }
 481
 482         return hash;
 483 }
 484
 485 LTTNG_HIDDEN
 486 bool process_attr_tracker_value_equal(const struct process_attr_value *a,
 487                 const struct process_attr_value *b)
 488 {
 489         if (a->type != b->type) {
 490                 return false;
 491         }
 492         switch (a->type) {
 493         case LTTNG_PROCESS_ATTR_VALUE_TYPE_PID:
 494                 return a->value.pid == b->value.pid;
 495         case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 496                 return a->value.uid == b->value.uid;
 497         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 498                 return a->value.gid == b->value.gid;
 499         case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 500                 return !strcmp(a->value.user_name, b->value.user_name);
 501         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 502                 return !strcmp(a->value.group_name, b->value.group_name);
 503         default:
 504                 abort();
 505         }
 506 }
 507
 508 LTTNG_HIDDEN
 509 void process_attr_value_destroy(struct process_attr_value *value)
 510 {
 511         if (!value) {
 512                 return;
 513         }
 514         if (is_value_type_name(value->type)) {
 515                 free(value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME ?
 516                                                 value->value.user_name :
 517                                                 value->value.group_name);
 518         }
 519         free(value);
 520 }