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                         goto error;
  89                 }
  90         }
  91
  92         if (domain != LTTNG_DOMAIN_UST && domain != LTTNG_DOMAIN_KERNEL) {
  93                 ERR("Only the user space and kernel space domains may be specified to configure process attribute trackers");
  94                 ret = LTTNG_ERR_UNSUPPORTED_DOMAIN;
  95                 goto error;
  96         }
  97
  98         if (!is_virtual_process_attr(process_attr) &&
  99                         domain != LTTNG_DOMAIN_KERNEL) {
 100                 ERR("Non-virtual process attributes can only be used in the kernel domain");
 101                 ret = LTTNG_ERR_UNSUPPORTED_DOMAIN;
 102                 goto error;
 103         }
 104
 105         /* Only expect a payload for name value types. */
 106         if (is_value_type_name(value_type) && value_view->size == 0) {
 107                 ret = LTTNG_ERR_INVALID_PROTOCOL;
 108                 goto error;
 109         } else if (!is_value_type_name(value_type) && value_view->size != 0) {
 110                 ret = LTTNG_ERR_INVALID_PROTOCOL;
 111                 goto error;
 112         }
 113
 114         value->type = value_type;
 115         switch (process_attr) {
 116         case LTTNG_PROCESS_ATTR_PROCESS_ID:
 117         case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID:
 118                 if (value_type != LTTNG_PROCESS_ATTR_VALUE_TYPE_PID) {
 119                         ERR("Invalid value type used for process ID process attribute");
 120                         ret = LTTNG_ERR_INVALID;
 121                         goto error;
 122                 }
 123                 value->value.pid =
 124                                 GET_INTEGRAL_COMM_VALUE(integral_value, pid_t);
 125                 break;
 126         case LTTNG_PROCESS_ATTR_USER_ID:
 127         case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID:
 128                 switch (value_type) {
 129                 case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 130                         value->value.uid = GET_INTEGRAL_COMM_VALUE(
 131                                         integral_value, uid_t);
 132                         break;
 133                 case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 134                         if (!name) {
 135                                 ret = LTTNG_ERR_INVALID;
 136                                 goto error;
 137                         }
 138
 139                         value->value.user_name = name;
 140                         name = NULL;
 141                         break;
 142                 default:
 143                         ERR("Invalid value type used for user ID process attribute");
 144                         ret = LTTNG_ERR_INVALID;
 145                         goto error;
 146                 }
 147                 break;
 148         case LTTNG_PROCESS_ATTR_GROUP_ID:
 149         case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID:
 150                 switch (value_type) {
 151                 case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 152                         value->value.gid = GET_INTEGRAL_COMM_VALUE(
 153                                         integral_value, gid_t);
 154                         break;
 155                 case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 156                         if (!name) {
 157                                 ret = LTTNG_ERR_INVALID;
 158                                 goto error;
 159                         }
 160
 161                         value->value.group_name = name;
 162                         name = NULL;
 163                         break;
 164                 default:
 165                         ERR("Invalid value type used for group ID process attribute");
 166                         ret = LTTNG_ERR_INVALID;
 167                         goto error;
 168                 }
 169                 break;
 170         default:
 171                 ret = LTTNG_ERR_INVALID_PROTOCOL;
 172                 goto error;
 173         }
 174
 175         *_value = value;
 176         value = NULL;
 177         free(name);
 178         return LTTNG_OK;
 179 error:
 180         free(name);
 181         process_attr_value_destroy(value);
 182         return ret;
 183 }
 184
 185 LTTNG_HIDDEN
 186 const char *lttng_process_attr_to_string(enum lttng_process_attr process_attr)
 187 {
 188         switch (process_attr) {
 189         case LTTNG_PROCESS_ATTR_PROCESS_ID:
 190                 return "process ID";
 191         case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID:
 192                 return "virtual process ID";
 193         case LTTNG_PROCESS_ATTR_USER_ID:
 194                 return "user ID";
 195         case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID:
 196                 return "virtual user ID";
 197         case LTTNG_PROCESS_ATTR_GROUP_ID:
 198                 return "group ID";
 199         case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID:
 200                 return "virtual group ID";
 201         default:
 202                 return "unknown process attribute";
 203         }
 204 }
 205
 206 static void process_attr_tracker_value_destructor(void *ptr)
 207 {
 208         struct process_attr_value *value = (typeof(value)) ptr;
 209
 210         process_attr_value_destroy(value);
 211 }
 212
 213 LTTNG_HIDDEN
 214 struct lttng_process_attr_values *lttng_process_attr_values_create(void)
 215 {
 216         struct lttng_process_attr_values *values = zmalloc(sizeof(*values));
 217
 218         if (!values) {
 219                 goto end;
 220         }
 221
 222         lttng_dynamic_pointer_array_init(
 223                         &values->array, process_attr_tracker_value_destructor);
 224 end:
 225         return values;
 226 }
 227
 228 LTTNG_HIDDEN
 229 unsigned int _lttng_process_attr_values_get_count(
 230                 const struct lttng_process_attr_values *values)
 231 {
 232         return (unsigned int) lttng_dynamic_pointer_array_get_count(
 233                         &values->array);
 234 }
 235
 236 LTTNG_HIDDEN
 237 const struct process_attr_value *lttng_process_attr_tracker_values_get_at_index(
 238                 const struct lttng_process_attr_values *values,
 239                 unsigned int index)
 240 {
 241         return lttng_dynamic_pointer_array_get_pointer(&values->array, index);
 242 }
 243
 244 static
 245 int process_attr_tracker_value_serialize(const struct process_attr_value *value,
 246                 struct lttng_dynamic_buffer *buffer)
 247 {
 248         int ret;
 249         struct process_attr_tracker_value_comm value_comm = {
 250                         .type = (int32_t) value->type,
 251         };
 252         const char *name = NULL;
 253
 254         switch (value->type) {
 255         case LTTNG_PROCESS_ATTR_VALUE_TYPE_PID:
 256                 SET_INTEGRAL_COMM_VALUE(
 257                                 &value_comm.value.integral, value->value.pid);
 258                 break;
 259         case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 260                 SET_INTEGRAL_COMM_VALUE(
 261                                 &value_comm.value.integral, value->value.uid);
 262                 break;
 263         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 264                 SET_INTEGRAL_COMM_VALUE(
 265                                 &value_comm.value.integral, value->value.gid);
 266                 break;
 267         case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 268                 name = value->value.user_name;
 269                 break;
 270         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 271                 name = value->value.group_name;
 272                 break;
 273         default:
 274                 abort();
 275         }
 276
 277         if (name) {
 278                 value_comm.value.name_len = strlen(name) + 1;
 279         }
 280
 281         ret = lttng_dynamic_buffer_append(
 282                         buffer, &value_comm, sizeof(value_comm));
 283         if (ret) {
 284                 goto end;
 285         }
 286
 287         if (name) {
 288                 ret = lttng_dynamic_buffer_append(
 289                                 buffer, name, value_comm.value.name_len);
 290         }
 291 end:
 292         return ret;
 293 }
 294
 295 LTTNG_HIDDEN
 296 int lttng_process_attr_values_serialize(
 297                 const struct lttng_process_attr_values *values,
 298                 struct lttng_dynamic_buffer *buffer)
 299 {
 300         int ret;
 301         unsigned int count, i;
 302         struct process_attr_tracker_values_comm_header header = {};
 303
 304         count = _lttng_process_attr_values_get_count(values);
 305         header.count = (uint32_t) count;
 306
 307         ret = lttng_dynamic_buffer_append(buffer, &header, sizeof(header));
 308         if (ret) {
 309                 goto end;
 310         }
 311
 312         for (i = 0; i < count; i++) {
 313                 const struct process_attr_value *value =
 314                                 lttng_process_attr_tracker_values_get_at_index(
 315                                                 values, i);
 316
 317                 ret = process_attr_tracker_value_serialize(value, buffer);
 318                 if (ret) {
 319                         goto end;
 320                 }
 321         }
 322 end:
 323         return ret;
 324 }
 325
 326 LTTNG_HIDDEN
 327 ssize_t lttng_process_attr_values_create_from_buffer(
 328                 enum lttng_domain_type domain,
 329                 enum lttng_process_attr process_attr,
 330                 const struct lttng_buffer_view *buffer_view,
 331                 struct lttng_process_attr_values **_values)
 332 {
 333         ssize_t offset;
 334         unsigned int i;
 335         struct lttng_process_attr_values *values;
 336         struct lttng_buffer_view header_view;
 337         const struct process_attr_tracker_values_comm_header *header;
 338
 339         values = lttng_process_attr_values_create();
 340         if (!values) {
 341                 goto error;
 342         }
 343
 344         header_view = lttng_buffer_view_from_view(
 345                         buffer_view, 0, sizeof(*header));
 346         if (!header_view.data) {
 347                 goto error;
 348         }
 349         offset = header_view.size;
 350         header = (typeof(header)) header_view.data;
 351
 352         /*
 353          * Check that the number of values is not absurdly large with respect to
 354          * the received buffer's size.
 355          */
 356         if (buffer_view->size <
 357                         header->count * sizeof(struct process_attr_tracker_value_comm)) {
 358                 goto error;
 359         }
 360         for (i = 0; i < (unsigned int) header->count; i++) {
 361                 int ret;
 362                 enum lttng_error_code ret_code;
 363                 const struct process_attr_tracker_value_comm *value_comm;
 364                 struct process_attr_value *value;
 365                 enum lttng_process_attr_value_type type;
 366                 struct lttng_buffer_view value_view;
 367                 struct lttng_buffer_view value_name_view = {};
 368
 369                 value_view = lttng_buffer_view_from_view(
 370                                 buffer_view, offset, sizeof(*value_comm));
 371                 if (!value_view.data) {
 372                         goto error;
 373                 }
 374
 375                 offset += value_view.size;
 376                 value_comm = (typeof(value_comm)) value_view.data;
 377                 type = (typeof(type)) value_comm->type;
 378
 379                 if (is_value_type_name(type)) {
 380                         value_name_view = lttng_buffer_view_from_view(
 381                                         buffer_view, offset,
 382                                         value_comm->value.name_len);
 383                         offset += value_name_view.size;
 384                 }
 385                 ret_code = process_attr_value_from_comm(domain, process_attr,
 386                                 type, &value_comm->value.integral,
 387                                 &value_name_view, &value);
 388                 if (ret_code != LTTNG_OK) {
 389                         goto error;
 390                 }
 391
 392                 ret = lttng_dynamic_pointer_array_add_pointer(
 393                                 &values->array, value);
 394                 if (ret) {
 395                         process_attr_value_destroy(value);
 396                         goto error;
 397                 }
 398         }
 399
 400         *_values = values;
 401         return offset;
 402 error:
 403         lttng_process_attr_values_destroy(values);
 404         return -1;
 405 }
 406
 407 LTTNG_HIDDEN
 408 void lttng_process_attr_values_destroy(struct lttng_process_attr_values *values)
 409 {
 410         if (!values) {
 411                 return;
 412         }
 413         lttng_dynamic_pointer_array_reset(&values->array);
 414         free(values);
 415 }
 416
 417 LTTNG_HIDDEN
 418 struct process_attr_value *process_attr_value_copy(
 419                 const struct process_attr_value *value)
 420 {
 421         struct process_attr_value *new_value = NULL;
 422
 423         if (!value) {
 424                 goto end;
 425         }
 426
 427         new_value = zmalloc(sizeof(*new_value));
 428         if (!new_value) {
 429                 goto end;
 430         }
 431         if (is_value_type_name(value->type)) {
 432                 const char *src =
 433                                 value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME ?
 434                                                 value->value.user_name :
 435                                                 value->value.group_name;
 436                 char **dst = value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME ?
 437                                              &new_value->value.user_name :
 438                                              &new_value->value.group_name;
 439
 440                 new_value->type = value->type;
 441                 *dst = strdup(src);
 442                 if (!*dst) {
 443                         goto error;
 444                 }
 445         } else {
 446                 *new_value = *value;
 447         }
 448 end:
 449         return new_value;
 450 error:
 451         free(new_value);
 452         return NULL;
 453 }
 454
 455 LTTNG_HIDDEN
 456 unsigned long process_attr_value_hash(const struct process_attr_value *a)
 457 {
 458         unsigned long hash = hash_key_ulong((void *) a->type, lttng_ht_seed);
 459
 460         switch (a->type) {
 461         case LTTNG_PROCESS_ATTR_VALUE_TYPE_PID:
 462                 hash ^= hash_key_ulong((void *) (unsigned long) a->value.pid,
 463                                 lttng_ht_seed);
 464                 break;
 465         case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 466                 hash ^= hash_key_ulong((void *) (unsigned long) a->value.uid,
 467                                 lttng_ht_seed);
 468                 break;
 469         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 470                 hash ^= hash_key_ulong((void *) (unsigned long) a->value.gid,
 471                                 lttng_ht_seed);
 472                 break;
 473         case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 474                 hash ^= hash_key_str(a->value.user_name, lttng_ht_seed);
 475                 break;
 476         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 477                 hash ^= hash_key_str(a->value.group_name, lttng_ht_seed);
 478                 break;
 479         default:
 480                 abort();
 481         }
 482
 483         return hash;
 484 }
 485
 486 LTTNG_HIDDEN
 487 bool process_attr_tracker_value_equal(const struct process_attr_value *a,
 488                 const struct process_attr_value *b)
 489 {
 490         if (a->type != b->type) {
 491                 return false;
 492         }
 493         switch (a->type) {
 494         case LTTNG_PROCESS_ATTR_VALUE_TYPE_PID:
 495                 return a->value.pid == b->value.pid;
 496         case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 497                 return a->value.uid == b->value.uid;
 498         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 499                 return a->value.gid == b->value.gid;
 500         case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 501                 return !strcmp(a->value.user_name, b->value.user_name);
 502         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 503                 return !strcmp(a->value.group_name, b->value.group_name);
 504         default:
 505                 abort();
 506         }
 507 }
 508
 509 LTTNG_HIDDEN
 510 void process_attr_value_destroy(struct process_attr_value *value)
 511 {
 512         if (!value) {
 513                 return;
 514         }
 515         if (is_value_type_name(value->type)) {
 516                 free(value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME ?
 517                                                 value->value.user_name :
 518                                                 value->value.group_name);
 519         }
 520         free(value);
 521 }