src/common/tracker.cpp

   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.hpp>
  14 #include <common/error.hpp>
  15 #include <common/hashtable/hashtable.hpp>
  16 #include <common/hashtable/utils.hpp>
  17 #include <common/tracker.hpp>
  18
  19 #include <stdbool.h>
  20
  21 #include <type_traits>
  22
  23 namespace {
  24 struct process_attr_tracker_values_comm_header {
  25         uint32_t count;
  26 } LTTNG_PACKED;
  27
  28 struct process_attr_tracker_value_comm {
  29         /* enum lttng_process_attr_value_type */
  30         int32_t type;
  31         union {
  32                 struct process_attr_integral_value_comm integral;
  33                 /* Includes the '\0' terminator. */
  34                 uint32_t name_len;
  35         } value;
  36 } LTTNG_PACKED;
  37 } /* namespace */
  38
  39 #define GET_INTEGRAL_COMM_VALUE(value_ptr, as_type)              \
  40         ((as_type)(std::is_signed<as_type>::value ? (value_ptr)->u._signed : \
  41                                         (value_ptr)->u._unsigned))
  42
  43 #define SET_INTEGRAL_COMM_VALUE(comm_value, val)                         \
  44         if (std::is_signed<typeof(val)>::value) {                                    \
  45                 (comm_value)->u._signed =                                  \
  46                                 (typeof((comm_value)->u._signed)) val;   \
  47         } else {                                                           \
  48                 (comm_value)->u._unsigned =                                \
  49                                 (typeof((comm_value)->u._unsigned)) val; \
  50         }
  51
  52 static inline bool is_virtual_process_attr(enum lttng_process_attr process_attr)
  53 {
  54         return process_attr == LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID ||
  55                process_attr == LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID ||
  56                process_attr == LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID;
  57 }
  58
  59 static inline bool is_value_type_name(
  60                 enum lttng_process_attr_value_type value_type)
  61 {
  62         return value_type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME ||
  63                value_type == LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME;
  64 }
  65
  66 enum lttng_error_code process_attr_value_from_comm(
  67                 enum lttng_domain_type domain,
  68                 enum lttng_process_attr process_attr,
  69                 enum lttng_process_attr_value_type value_type,
  70                 const struct process_attr_integral_value_comm *integral_value,
  71                 const struct lttng_buffer_view *value_view,
  72                 struct process_attr_value **_value)
  73 {
  74         char *name = NULL;
  75         enum lttng_error_code ret = LTTNG_OK;
  76         struct process_attr_value *value = zmalloc<process_attr_value>();
  77
  78         if (!value) {
  79                 ret = LTTNG_ERR_NOMEM;
  80                 goto error;
  81         }
  82
  83         if (value_view && value_view->size > 0) {
  84                 if (value_view->data[value_view->size - 1] != '\0') {
  85                         ret = LTTNG_ERR_INVALID;
  86                         goto error;
  87                 }
  88                 name = strdup(value_view->data);
  89                 if (!name) {
  90                         ret = LTTNG_ERR_NOMEM;
  91                         goto error;
  92                 }
  93         }
  94
  95         if (domain != LTTNG_DOMAIN_UST && domain != LTTNG_DOMAIN_KERNEL) {
  96                 ERR("Only the user space and kernel space domains may be specified to configure process attribute trackers");
  97                 ret = LTTNG_ERR_UNSUPPORTED_DOMAIN;
  98                 goto error;
  99         }
 100
 101         if (!is_virtual_process_attr(process_attr) &&
 102                         domain != LTTNG_DOMAIN_KERNEL) {
 103                 ERR("Non-virtual process attributes can only be used in the kernel domain");
 104                 ret = LTTNG_ERR_UNSUPPORTED_DOMAIN;
 105                 goto error;
 106         }
 107
 108         /* Only expect a payload for name value types. */
 109         if (is_value_type_name(value_type) &&
 110                         (!value_view || value_view->size == 0)) {
 111                 ret = LTTNG_ERR_INVALID_PROTOCOL;
 112                 goto error;
 113         } else if (!is_value_type_name(value_type) && value_view &&
 114                         value_view->size != 0) {
 115                 ret = LTTNG_ERR_INVALID_PROTOCOL;
 116                 goto error;
 117         }
 118
 119         value->type = value_type;
 120         switch (process_attr) {
 121         case LTTNG_PROCESS_ATTR_PROCESS_ID:
 122         case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID:
 123                 if (value_type != LTTNG_PROCESS_ATTR_VALUE_TYPE_PID) {
 124                         ERR("Invalid value type used for process ID process attribute");
 125                         ret = LTTNG_ERR_INVALID;
 126                         goto error;
 127                 }
 128                 value->value.pid =
 129                                 GET_INTEGRAL_COMM_VALUE(integral_value, pid_t);
 130                 break;
 131         case LTTNG_PROCESS_ATTR_USER_ID:
 132         case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID:
 133                 switch (value_type) {
 134                 case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 135                         value->value.uid = GET_INTEGRAL_COMM_VALUE(
 136                                         integral_value, uid_t);
 137                         break;
 138                 case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 139                         if (!name) {
 140                                 ret = LTTNG_ERR_INVALID;
 141                                 goto error;
 142                         }
 143
 144                         value->value.user_name = name;
 145                         name = NULL;
 146                         break;
 147                 default:
 148                         ERR("Invalid value type used for user ID process attribute");
 149                         ret = LTTNG_ERR_INVALID;
 150                         goto error;
 151                 }
 152                 break;
 153         case LTTNG_PROCESS_ATTR_GROUP_ID:
 154         case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID:
 155                 switch (value_type) {
 156                 case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 157                         value->value.gid = GET_INTEGRAL_COMM_VALUE(
 158                                         integral_value, gid_t);
 159                         break;
 160                 case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 161                         if (!name) {
 162                                 ret = LTTNG_ERR_INVALID;
 163                                 goto error;
 164                         }
 165
 166                         value->value.group_name = name;
 167                         name = NULL;
 168                         break;
 169                 default:
 170                         ERR("Invalid value type used for group ID process attribute");
 171                         ret = LTTNG_ERR_INVALID;
 172                         goto error;
 173                 }
 174                 break;
 175         default:
 176                 ret = LTTNG_ERR_INVALID_PROTOCOL;
 177                 goto error;
 178         }
 179
 180         *_value = value;
 181         value = NULL;
 182         free(name);
 183         return LTTNG_OK;
 184 error:
 185         free(name);
 186         process_attr_value_destroy(value);
 187         return ret;
 188 }
 189
 190 const char *lttng_process_attr_to_string(enum lttng_process_attr process_attr)
 191 {
 192         switch (process_attr) {
 193         case LTTNG_PROCESS_ATTR_PROCESS_ID:
 194                 return "process ID";
 195         case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID:
 196                 return "virtual process ID";
 197         case LTTNG_PROCESS_ATTR_USER_ID:
 198                 return "user ID";
 199         case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID:
 200                 return "virtual user ID";
 201         case LTTNG_PROCESS_ATTR_GROUP_ID:
 202                 return "group ID";
 203         case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID:
 204                 return "virtual group ID";
 205         default:
 206                 return "unknown process attribute";
 207         }
 208 }
 209
 210 static void process_attr_tracker_value_destructor(void *ptr)
 211 {
 212         struct process_attr_value *value = (typeof(value)) ptr;
 213
 214         process_attr_value_destroy(value);
 215 }
 216
 217 struct lttng_process_attr_values *lttng_process_attr_values_create(void)
 218 {
 219         struct lttng_process_attr_values *values = zmalloc<lttng_process_attr_values>();
 220
 221         if (!values) {
 222                 goto end;
 223         }
 224
 225         lttng_dynamic_pointer_array_init(
 226                         &values->array, process_attr_tracker_value_destructor);
 227 end:
 228         return values;
 229 }
 230
 231 unsigned int _lttng_process_attr_values_get_count(
 232                 const struct lttng_process_attr_values *values)
 233 {
 234         return (unsigned int) lttng_dynamic_pointer_array_get_count(
 235                         &values->array);
 236 }
 237
 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 (process_attr_value *) 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                         .value = {},
 253         };
 254         const char *name = NULL;
 255
 256         switch (value->type) {
 257         case LTTNG_PROCESS_ATTR_VALUE_TYPE_PID:
 258                 SET_INTEGRAL_COMM_VALUE(
 259                                 &value_comm.value.integral, value->value.pid);
 260                 break;
 261         case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 262                 SET_INTEGRAL_COMM_VALUE(
 263                                 &value_comm.value.integral, value->value.uid);
 264                 break;
 265         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 266                 SET_INTEGRAL_COMM_VALUE(
 267                                 &value_comm.value.integral, value->value.gid);
 268                 break;
 269         case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 270                 name = value->value.user_name;
 271                 break;
 272         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 273                 name = value->value.group_name;
 274                 break;
 275         default:
 276                 abort();
 277         }
 278
 279         if (name) {
 280                 value_comm.value.name_len = strlen(name) + 1;
 281         }
 282
 283         ret = lttng_dynamic_buffer_append(
 284                         buffer, &value_comm, sizeof(value_comm));
 285         if (ret) {
 286                 goto end;
 287         }
 288
 289         if (name) {
 290                 ret = lttng_dynamic_buffer_append(
 291                                 buffer, name, value_comm.value.name_len);
 292         }
 293 end:
 294         return ret;
 295 }
 296
 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 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 (!lttng_buffer_view_is_valid(&header_view)) {
 347                 goto error;
 348         }
 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 (!lttng_buffer_view_is_valid(&value_view)) {
 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                         if (!lttng_buffer_view_is_valid(&value_name_view)) {
 385                                 goto error;
 386                         }
 387
 388                         offset += value_name_view.size;
 389                 }
 390
 391                 ret_code = process_attr_value_from_comm(domain, process_attr,
 392                                 type, &value_comm->value.integral,
 393                                 &value_name_view, &value);
 394                 if (ret_code != LTTNG_OK) {
 395                         goto error;
 396                 }
 397
 398                 ret = lttng_dynamic_pointer_array_add_pointer(
 399                                 &values->array, value);
 400                 if (ret) {
 401                         process_attr_value_destroy(value);
 402                         goto error;
 403                 }
 404         }
 405
 406         *_values = values;
 407         return offset;
 408 error:
 409         lttng_process_attr_values_destroy(values);
 410         return -1;
 411 }
 412
 413 void lttng_process_attr_values_destroy(struct lttng_process_attr_values *values)
 414 {
 415         if (!values) {
 416                 return;
 417         }
 418         lttng_dynamic_pointer_array_reset(&values->array);
 419         free(values);
 420 }
 421
 422 struct process_attr_value *process_attr_value_copy(
 423                 const struct process_attr_value *value)
 424 {
 425         struct process_attr_value *new_value = NULL;
 426
 427         if (!value) {
 428                 goto end;
 429         }
 430
 431         new_value = zmalloc<process_attr_value>();
 432         if (!new_value) {
 433                 goto end;
 434         }
 435         if (is_value_type_name(value->type)) {
 436                 const char *src =
 437                                 value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME ?
 438                                                 value->value.user_name :
 439                                                 value->value.group_name;
 440                 char **dst = value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME ?
 441                                              &new_value->value.user_name :
 442                                              &new_value->value.group_name;
 443
 444                 new_value->type = value->type;
 445                 *dst = strdup(src);
 446                 if (!*dst) {
 447                         goto error;
 448                 }
 449         } else {
 450                 *new_value = *value;
 451         }
 452 end:
 453         return new_value;
 454 error:
 455         free(new_value);
 456         return NULL;
 457 }
 458
 459 unsigned long process_attr_value_hash(const struct process_attr_value *a)
 460 {
 461         unsigned long hash = hash_key_ulong((void *) a->type, lttng_ht_seed);
 462
 463         switch (a->type) {
 464         case LTTNG_PROCESS_ATTR_VALUE_TYPE_PID:
 465                 hash ^= hash_key_ulong((void *) (unsigned long) a->value.pid,
 466                                 lttng_ht_seed);
 467                 break;
 468         case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 469                 hash ^= hash_key_ulong((void *) (unsigned long) a->value.uid,
 470                                 lttng_ht_seed);
 471                 break;
 472         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 473                 hash ^= hash_key_ulong((void *) (unsigned long) a->value.gid,
 474                                 lttng_ht_seed);
 475                 break;
 476         case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 477                 hash ^= hash_key_str(a->value.user_name, lttng_ht_seed);
 478                 break;
 479         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 480                 hash ^= hash_key_str(a->value.group_name, lttng_ht_seed);
 481                 break;
 482         default:
 483                 abort();
 484         }
 485
 486         return hash;
 487 }
 488
 489 bool process_attr_tracker_value_equal(const struct process_attr_value *a,
 490                 const struct process_attr_value *b)
 491 {
 492         if (a->type != b->type) {
 493                 return false;
 494         }
 495         switch (a->type) {
 496         case LTTNG_PROCESS_ATTR_VALUE_TYPE_PID:
 497                 return a->value.pid == b->value.pid;
 498         case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 499                 return a->value.uid == b->value.uid;
 500         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 501                 return a->value.gid == b->value.gid;
 502         case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 503                 return !strcmp(a->value.user_name, b->value.user_name);
 504         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 505                 return !strcmp(a->value.group_name, b->value.group_name);
 506         default:
 507                 abort();
 508         }
 509 }
 510
 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 }