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 enum lttng_error_code process_attr_value_from_comm(
  63                 enum lttng_domain_type domain,
  64                 enum lttng_process_attr process_attr,
  65                 enum lttng_process_attr_value_type value_type,
  66                 const struct process_attr_integral_value_comm *integral_value,
  67                 const struct lttng_buffer_view *value_view,
  68                 struct process_attr_value **_value)
  69 {
  70         char *name = NULL;
  71         enum lttng_error_code ret = LTTNG_OK;
  72         struct process_attr_value *value = zmalloc(sizeof(*value));
  73
  74         if (!value) {
  75                 ret = LTTNG_ERR_NOMEM;
  76                 goto error;
  77         }
  78
  79         if (value_view && value_view->size > 0) {
  80                 if (value_view->data[value_view->size - 1] != '\0') {
  81                         ret = LTTNG_ERR_INVALID;
  82                         goto error;
  83                 }
  84                 name = strdup(value_view->data);
  85                 if (!name) {
  86                         ret = LTTNG_ERR_NOMEM;
  87                         goto error;
  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) &&
 106                         (!value_view || value_view->size == 0)) {
 107                 ret = LTTNG_ERR_INVALID_PROTOCOL;
 108                 goto error;
 109         } else if (!is_value_type_name(value_type) && value_view &&
 110                         value_view->size != 0) {
 111                 ret = LTTNG_ERR_INVALID_PROTOCOL;
 112                 goto error;
 113         }
 114
 115         value->type = value_type;
 116         switch (process_attr) {
 117         case LTTNG_PROCESS_ATTR_PROCESS_ID:
 118         case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID:
 119                 if (value_type != LTTNG_PROCESS_ATTR_VALUE_TYPE_PID) {
 120                         ERR("Invalid value type used for process ID process attribute");
 121                         ret = LTTNG_ERR_INVALID;
 122                         goto error;
 123                 }
 124                 value->value.pid =
 125                                 GET_INTEGRAL_COMM_VALUE(integral_value, pid_t);
 126                 break;
 127         case LTTNG_PROCESS_ATTR_USER_ID:
 128         case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID:
 129                 switch (value_type) {
 130                 case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 131                         value->value.uid = GET_INTEGRAL_COMM_VALUE(
 132                                         integral_value, uid_t);
 133                         break;
 134                 case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 135                         if (!name) {
 136                                 ret = LTTNG_ERR_INVALID;
 137                                 goto error;
 138                         }
 139
 140                         value->value.user_name = name;
 141                         name = NULL;
 142                         break;
 143                 default:
 144                         ERR("Invalid value type used for user ID process attribute");
 145                         ret = LTTNG_ERR_INVALID;
 146                         goto error;
 147                 }
 148                 break;
 149         case LTTNG_PROCESS_ATTR_GROUP_ID:
 150         case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID:
 151                 switch (value_type) {
 152                 case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 153                         value->value.gid = GET_INTEGRAL_COMM_VALUE(
 154                                         integral_value, gid_t);
 155                         break;
 156                 case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 157                         if (!name) {
 158                                 ret = LTTNG_ERR_INVALID;
 159                                 goto error;
 160                         }
 161
 162                         value->value.group_name = name;
 163                         name = NULL;
 164                         break;
 165                 default:
 166                         ERR("Invalid value type used for group ID process attribute");
 167                         ret = LTTNG_ERR_INVALID;
 168                         goto error;
 169                 }
 170                 break;
 171         default:
 172                 ret = LTTNG_ERR_INVALID_PROTOCOL;
 173                 goto error;
 174         }
 175
 176         *_value = value;
 177         value = NULL;
 178         free(name);
 179         return LTTNG_OK;
 180 error:
 181         free(name);
 182         process_attr_value_destroy(value);
 183         return ret;
 184 }
 185
 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 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 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 const struct process_attr_value *lttng_process_attr_tracker_values_get_at_index(
 235                 const struct lttng_process_attr_values *values,
 236                 unsigned int index)
 237 {
 238         return lttng_dynamic_pointer_array_get_pointer(&values->array, index);
 239 }
 240
 241 static
 242 int process_attr_tracker_value_serialize(const struct process_attr_value *value,
 243                 struct lttng_dynamic_buffer *buffer)
 244 {
 245         int ret;
 246         struct process_attr_tracker_value_comm value_comm = {
 247                         .type = (int32_t) value->type,
 248         };
 249         const char *name = NULL;
 250
 251         switch (value->type) {
 252         case LTTNG_PROCESS_ATTR_VALUE_TYPE_PID:
 253                 SET_INTEGRAL_COMM_VALUE(
 254                                 &value_comm.value.integral, value->value.pid);
 255                 break;
 256         case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 257                 SET_INTEGRAL_COMM_VALUE(
 258                                 &value_comm.value.integral, value->value.uid);
 259                 break;
 260         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 261                 SET_INTEGRAL_COMM_VALUE(
 262                                 &value_comm.value.integral, value->value.gid);
 263                 break;
 264         case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 265                 name = value->value.user_name;
 266                 break;
 267         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 268                 name = value->value.group_name;
 269                 break;
 270         default:
 271                 abort();
 272         }
 273
 274         if (name) {
 275                 value_comm.value.name_len = strlen(name) + 1;
 276         }
 277
 278         ret = lttng_dynamic_buffer_append(
 279                         buffer, &value_comm, sizeof(value_comm));
 280         if (ret) {
 281                 goto end;
 282         }
 283
 284         if (name) {
 285                 ret = lttng_dynamic_buffer_append(
 286                                 buffer, name, value_comm.value.name_len);
 287         }
 288 end:
 289         return ret;
 290 }
 291
 292 int lttng_process_attr_values_serialize(
 293                 const struct lttng_process_attr_values *values,
 294                 struct lttng_dynamic_buffer *buffer)
 295 {
 296         int ret;
 297         unsigned int count, i;
 298         struct process_attr_tracker_values_comm_header header = {};
 299
 300         count = _lttng_process_attr_values_get_count(values);
 301         header.count = (uint32_t) count;
 302
 303         ret = lttng_dynamic_buffer_append(buffer, &header, sizeof(header));
 304         if (ret) {
 305                 goto end;
 306         }
 307
 308         for (i = 0; i < count; i++) {
 309                 const struct process_attr_value *value =
 310                                 lttng_process_attr_tracker_values_get_at_index(
 311                                                 values, i);
 312
 313                 ret = process_attr_tracker_value_serialize(value, buffer);
 314                 if (ret) {
 315                         goto end;
 316                 }
 317         }
 318 end:
 319         return ret;
 320 }
 321
 322 ssize_t lttng_process_attr_values_create_from_buffer(
 323                 enum lttng_domain_type domain,
 324                 enum lttng_process_attr process_attr,
 325                 const struct lttng_buffer_view *buffer_view,
 326                 struct lttng_process_attr_values **_values)
 327 {
 328         ssize_t offset;
 329         unsigned int i;
 330         struct lttng_process_attr_values *values;
 331         struct lttng_buffer_view header_view;
 332         const struct process_attr_tracker_values_comm_header *header;
 333
 334         values = lttng_process_attr_values_create();
 335         if (!values) {
 336                 goto error;
 337         }
 338
 339         header_view = lttng_buffer_view_from_view(
 340                         buffer_view, 0, sizeof(*header));
 341         if (!lttng_buffer_view_is_valid(&header_view)) {
 342                 goto error;
 343         }
 344
 345         offset = header_view.size;
 346         header = (typeof(header)) header_view.data;
 347
 348         /*
 349          * Check that the number of values is not absurdly large with respect to
 350          * the received buffer's size.
 351          */
 352         if (buffer_view->size <
 353                         header->count * sizeof(struct process_attr_tracker_value_comm)) {
 354                 goto error;
 355         }
 356         for (i = 0; i < (unsigned int) header->count; i++) {
 357                 int ret;
 358                 enum lttng_error_code ret_code;
 359                 const struct process_attr_tracker_value_comm *value_comm;
 360                 struct process_attr_value *value;
 361                 enum lttng_process_attr_value_type type;
 362                 struct lttng_buffer_view value_view;
 363                 struct lttng_buffer_view value_name_view = {};
 364
 365                 value_view = lttng_buffer_view_from_view(
 366                                 buffer_view, offset, sizeof(*value_comm));
 367                 if (!lttng_buffer_view_is_valid(&value_view)) {
 368                         goto error;
 369                 }
 370
 371                 offset += value_view.size;
 372                 value_comm = (typeof(value_comm)) value_view.data;
 373                 type = (typeof(type)) value_comm->type;
 374
 375                 if (is_value_type_name(type)) {
 376                         value_name_view = lttng_buffer_view_from_view(
 377                                         buffer_view, offset,
 378                                         value_comm->value.name_len);
 379                         if (!lttng_buffer_view_is_valid(&value_name_view)) {
 380                                 goto error;
 381                         }
 382
 383                         offset += value_name_view.size;
 384                 }
 385
 386                 ret_code = process_attr_value_from_comm(domain, process_attr,
 387                                 type, &value_comm->value.integral,
 388                                 &value_name_view, &value);
 389                 if (ret_code != LTTNG_OK) {
 390                         goto error;
 391                 }
 392
 393                 ret = lttng_dynamic_pointer_array_add_pointer(
 394                                 &values->array, value);
 395                 if (ret) {
 396                         process_attr_value_destroy(value);
 397                         goto error;
 398                 }
 399         }
 400
 401         *_values = values;
 402         return offset;
 403 error:
 404         lttng_process_attr_values_destroy(values);
 405         return -1;
 406 }
 407
 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 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 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 bool process_attr_tracker_value_equal(const struct process_attr_value *a,
 485                 const struct process_attr_value *b)
 486 {
 487         if (a->type != b->type) {
 488                 return false;
 489         }
 490         switch (a->type) {
 491         case LTTNG_PROCESS_ATTR_VALUE_TYPE_PID:
 492                 return a->value.pid == b->value.pid;
 493         case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 494                 return a->value.uid == b->value.uid;
 495         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 496                 return a->value.gid == b->value.gid;
 497         case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 498                 return !strcmp(a->value.user_name, b->value.user_name);
 499         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 500                 return !strcmp(a->value.group_name, b->value.group_name);
 501         default:
 502                 abort();
 503         }
 504 }
 505
 506 void process_attr_value_destroy(struct process_attr_value *value)
 507 {
 508         if (!value) {
 509                 return;
 510         }
 511         if (is_value_type_name(value->type)) {
 512                 free(value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME ?
 513                                                 value->value.user_name :
 514                                                 value->value.group_name);
 515         }
 516         free(value);
 517 }