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 &&
 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 LTTNG_HIDDEN
 187 const char *lttng_process_attr_to_string(enum lttng_process_attr process_attr)
 188 {
 189         switch (process_attr) {
 190         case LTTNG_PROCESS_ATTR_PROCESS_ID:
 191                 return "process ID";
 192         case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID:
 193                 return "virtual process ID";
 194         case LTTNG_PROCESS_ATTR_USER_ID:
 195                 return "user ID";
 196         case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID:
 197                 return "virtual user ID";
 198         case LTTNG_PROCESS_ATTR_GROUP_ID:
 199                 return "group ID";
 200         case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID:
 201                 return "virtual group ID";
 202         default:
 203                 return "unknown process attribute";
 204         }
 205 }
 206
 207 static void process_attr_tracker_value_destructor(void *ptr)
 208 {
 209         struct process_attr_value *value = (typeof(value)) ptr;
 210
 211         process_attr_value_destroy(value);
 212 }
 213
 214 LTTNG_HIDDEN
 215 struct lttng_process_attr_values *lttng_process_attr_values_create(void)
 216 {
 217         struct lttng_process_attr_values *values = zmalloc(sizeof(*values));
 218
 219         if (!values) {
 220                 goto end;
 221         }
 222
 223         lttng_dynamic_pointer_array_init(
 224                         &values->array, process_attr_tracker_value_destructor);
 225 end:
 226         return values;
 227 }
 228
 229 LTTNG_HIDDEN
 230 unsigned int _lttng_process_attr_values_get_count(
 231                 const struct lttng_process_attr_values *values)
 232 {
 233         return (unsigned int) lttng_dynamic_pointer_array_get_count(
 234                         &values->array);
 235 }
 236
 237 LTTNG_HIDDEN
 238 const struct process_attr_value *lttng_process_attr_tracker_values_get_at_index(
 239                 const struct lttng_process_attr_values *values,
 240                 unsigned int index)
 241 {
 242         return lttng_dynamic_pointer_array_get_pointer(&values->array, index);
 243 }
 244
 245 static
 246 int process_attr_tracker_value_serialize(const struct process_attr_value *value,
 247                 struct lttng_dynamic_buffer *buffer)
 248 {
 249         int ret;
 250         struct process_attr_tracker_value_comm value_comm = {
 251                         .type = (int32_t) value->type,
 252         };
 253         const char *name = NULL;
 254
 255         switch (value->type) {
 256         case LTTNG_PROCESS_ATTR_VALUE_TYPE_PID:
 257                 SET_INTEGRAL_COMM_VALUE(
 258                                 &value_comm.value.integral, value->value.pid);
 259                 break;
 260         case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 261                 SET_INTEGRAL_COMM_VALUE(
 262                                 &value_comm.value.integral, value->value.uid);
 263                 break;
 264         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 265                 SET_INTEGRAL_COMM_VALUE(
 266                                 &value_comm.value.integral, value->value.gid);
 267                 break;
 268         case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 269                 name = value->value.user_name;
 270                 break;
 271         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 272                 name = value->value.group_name;
 273                 break;
 274         default:
 275                 abort();
 276         }
 277
 278         if (name) {
 279                 value_comm.value.name_len = strlen(name) + 1;
 280         }
 281
 282         ret = lttng_dynamic_buffer_append(
 283                         buffer, &value_comm, sizeof(value_comm));
 284         if (ret) {
 285                 goto end;
 286         }
 287
 288         if (name) {
 289                 ret = lttng_dynamic_buffer_append(
 290                                 buffer, name, value_comm.value.name_len);
 291         }
 292 end:
 293         return ret;
 294 }
 295
 296 LTTNG_HIDDEN
 297 int lttng_process_attr_values_serialize(
 298                 const struct lttng_process_attr_values *values,
 299                 struct lttng_dynamic_buffer *buffer)
 300 {
 301         int ret;
 302         unsigned int count, i;
 303         struct process_attr_tracker_values_comm_header header = {};
 304
 305         count = _lttng_process_attr_values_get_count(values);
 306         header.count = (uint32_t) count;
 307
 308         ret = lttng_dynamic_buffer_append(buffer, &header, sizeof(header));
 309         if (ret) {
 310                 goto end;
 311         }
 312
 313         for (i = 0; i < count; i++) {
 314                 const struct process_attr_value *value =
 315                                 lttng_process_attr_tracker_values_get_at_index(
 316                                                 values, i);
 317
 318                 ret = process_attr_tracker_value_serialize(value, buffer);
 319                 if (ret) {
 320                         goto end;
 321                 }
 322         }
 323 end:
 324         return ret;
 325 }
 326
 327 LTTNG_HIDDEN
 328 ssize_t lttng_process_attr_values_create_from_buffer(
 329                 enum lttng_domain_type domain,
 330                 enum lttng_process_attr process_attr,
 331                 const struct lttng_buffer_view *buffer_view,
 332                 struct lttng_process_attr_values **_values)
 333 {
 334         ssize_t offset;
 335         unsigned int i;
 336         struct lttng_process_attr_values *values;
 337         struct lttng_buffer_view header_view;
 338         const struct process_attr_tracker_values_comm_header *header;
 339
 340         values = lttng_process_attr_values_create();
 341         if (!values) {
 342                 goto error;
 343         }
 344
 345         header_view = lttng_buffer_view_from_view(
 346                         buffer_view, 0, sizeof(*header));
 347         if (!header_view.data) {
 348                 goto error;
 349         }
 350         offset = header_view.size;
 351         header = (typeof(header)) header_view.data;
 352
 353         /*
 354          * Check that the number of values is not absurdly large with respect to
 355          * the received buffer's size.
 356          */
 357         if (buffer_view->size <
 358                         header->count * sizeof(struct process_attr_tracker_value_comm)) {
 359                 goto error;
 360         }
 361         for (i = 0; i < (unsigned int) header->count; i++) {
 362                 int ret;
 363                 enum lttng_error_code ret_code;
 364                 const struct process_attr_tracker_value_comm *value_comm;
 365                 struct process_attr_value *value;
 366                 enum lttng_process_attr_value_type type;
 367                 struct lttng_buffer_view value_view;
 368                 struct lttng_buffer_view value_name_view = {};
 369
 370                 value_view = lttng_buffer_view_from_view(
 371                                 buffer_view, offset, sizeof(*value_comm));
 372                 if (!value_view.data) {
 373                         goto error;
 374                 }
 375
 376                 offset += value_view.size;
 377                 value_comm = (typeof(value_comm)) value_view.data;
 378                 type = (typeof(type)) value_comm->type;
 379
 380                 if (is_value_type_name(type)) {
 381                         value_name_view = lttng_buffer_view_from_view(
 382                                         buffer_view, offset,
 383                                         value_comm->value.name_len);
 384                         offset += value_name_view.size;
 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 LTTNG_HIDDEN
 409 void lttng_process_attr_values_destroy(struct lttng_process_attr_values *values)
 410 {
 411         if (!values) {
 412                 return;
 413         }
 414         lttng_dynamic_pointer_array_reset(&values->array);
 415         free(values);
 416 }
 417
 418 LTTNG_HIDDEN
 419 struct process_attr_value *process_attr_value_copy(
 420                 const struct process_attr_value *value)
 421 {
 422         struct process_attr_value *new_value = NULL;
 423
 424         if (!value) {
 425                 goto end;
 426         }
 427
 428         new_value = zmalloc(sizeof(*new_value));
 429         if (!new_value) {
 430                 goto end;
 431         }
 432         if (is_value_type_name(value->type)) {
 433                 const char *src =
 434                                 value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME ?
 435                                                 value->value.user_name :
 436                                                 value->value.group_name;
 437                 char **dst = value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME ?
 438                                              &new_value->value.user_name :
 439                                              &new_value->value.group_name;
 440
 441                 new_value->type = value->type;
 442                 *dst = strdup(src);
 443                 if (!*dst) {
 444                         goto error;
 445                 }
 446         } else {
 447                 *new_value = *value;
 448         }
 449 end:
 450         return new_value;
 451 error:
 452         free(new_value);
 453         return NULL;
 454 }
 455
 456 LTTNG_HIDDEN
 457 unsigned long process_attr_value_hash(const struct process_attr_value *a)
 458 {
 459         unsigned long hash = hash_key_ulong((void *) a->type, lttng_ht_seed);
 460
 461         switch (a->type) {
 462         case LTTNG_PROCESS_ATTR_VALUE_TYPE_PID:
 463                 hash ^= hash_key_ulong((void *) (unsigned long) a->value.pid,
 464                                 lttng_ht_seed);
 465                 break;
 466         case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 467                 hash ^= hash_key_ulong((void *) (unsigned long) a->value.uid,
 468                                 lttng_ht_seed);
 469                 break;
 470         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 471                 hash ^= hash_key_ulong((void *) (unsigned long) a->value.gid,
 472                                 lttng_ht_seed);
 473                 break;
 474         case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 475                 hash ^= hash_key_str(a->value.user_name, lttng_ht_seed);
 476                 break;
 477         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 478                 hash ^= hash_key_str(a->value.group_name, lttng_ht_seed);
 479                 break;
 480         default:
 481                 abort();
 482         }
 483
 484         return hash;
 485 }
 486
 487 LTTNG_HIDDEN
 488 bool process_attr_tracker_value_equal(const struct process_attr_value *a,
 489                 const struct process_attr_value *b)
 490 {
 491         if (a->type != b->type) {
 492                 return false;
 493         }
 494         switch (a->type) {
 495         case LTTNG_PROCESS_ATTR_VALUE_TYPE_PID:
 496                 return a->value.pid == b->value.pid;
 497         case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 498                 return a->value.uid == b->value.uid;
 499         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 500                 return a->value.gid == b->value.gid;
 501         case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 502                 return !strcmp(a->value.user_name, b->value.user_name);
 503         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 504                 return !strcmp(a->value.group_name, b->value.group_name);
 505         default:
 506                 abort();
 507         }
 508 }
 509
 510 LTTNG_HIDDEN
 511 void process_attr_value_destroy(struct process_attr_value *value)
 512 {
 513         if (!value) {
 514                 return;
 515         }
 516         if (is_value_type_name(value->type)) {
 517                 free(value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME ?
 518                                                 value->value.user_name :
 519                                                 value->value.group_name);
 520         }
 521         free(value);
 522 }