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 struct process_attr_tracker_values_comm_header {
  24         uint32_t count;
  25 };
  26
  27 struct process_attr_tracker_value_comm {
  28         /* enum lttng_process_attr_value_type */
  29         int32_t type;
  30         union {
  31                 struct process_attr_integral_value_comm integral;
  32                 /* Includes the '\0' terminator. */
  33                 uint32_t name_len;
  34         } value;
  35 };
  36
  37 #define GET_INTEGRAL_COMM_VALUE(value_ptr, as_type)              \
  38         ((as_type)(std::is_signed<as_type>::value ? (value_ptr)->u._signed : \
  39                                         (value_ptr)->u._unsigned))
  40
  41 #define SET_INTEGRAL_COMM_VALUE(comm_value, val)                         \
  42         if (std::is_signed<typeof(val)>::value) {                                    \
  43                 (comm_value)->u._signed =                                  \
  44                                 (typeof((comm_value)->u._signed)) val;   \
  45         } else {                                                           \
  46                 (comm_value)->u._unsigned =                                \
  47                                 (typeof((comm_value)->u._unsigned)) val; \
  48         }
  49
  50 static inline bool is_virtual_process_attr(enum lttng_process_attr process_attr)
  51 {
  52         return process_attr == LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID ||
  53                process_attr == LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID ||
  54                process_attr == LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID;
  55 }
  56
  57 static inline bool is_value_type_name(
  58                 enum lttng_process_attr_value_type value_type)
  59 {
  60         return value_type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME ||
  61                value_type == LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME;
  62 }
  63
  64 enum lttng_error_code process_attr_value_from_comm(
  65                 enum lttng_domain_type domain,
  66                 enum lttng_process_attr process_attr,
  67                 enum lttng_process_attr_value_type value_type,
  68                 const struct process_attr_integral_value_comm *integral_value,
  69                 const struct lttng_buffer_view *value_view,
  70                 struct process_attr_value **_value)
  71 {
  72         char *name = NULL;
  73         enum lttng_error_code ret = LTTNG_OK;
  74         struct process_attr_value *value = (process_attr_value *) zmalloc(sizeof(*value));
  75
  76         if (!value) {
  77                 ret = LTTNG_ERR_NOMEM;
  78                 goto error;
  79         }
  80
  81         if (value_view && value_view->size > 0) {
  82                 if (value_view->data[value_view->size - 1] != '\0') {
  83                         ret = LTTNG_ERR_INVALID;
  84                         goto error;
  85                 }
  86                 name = strdup(value_view->data);
  87                 if (!name) {
  88                         ret = LTTNG_ERR_NOMEM;
  89                         goto error;
  90                 }
  91         }
  92
  93         if (domain != LTTNG_DOMAIN_UST && domain != LTTNG_DOMAIN_KERNEL) {
  94                 ERR("Only the user space and kernel space domains may be specified to configure process attribute trackers");
  95                 ret = LTTNG_ERR_UNSUPPORTED_DOMAIN;
  96                 goto error;
  97         }
  98
  99         if (!is_virtual_process_attr(process_attr) &&
 100                         domain != LTTNG_DOMAIN_KERNEL) {
 101                 ERR("Non-virtual process attributes can only be used in the kernel domain");
 102                 ret = LTTNG_ERR_UNSUPPORTED_DOMAIN;
 103                 goto error;
 104         }
 105
 106         /* Only expect a payload for name value types. */
 107         if (is_value_type_name(value_type) &&
 108                         (!value_view || value_view->size == 0)) {
 109                 ret = LTTNG_ERR_INVALID_PROTOCOL;
 110                 goto error;
 111         } else if (!is_value_type_name(value_type) && value_view &&
 112                         value_view->size != 0) {
 113                 ret = LTTNG_ERR_INVALID_PROTOCOL;
 114                 goto error;
 115         }
 116
 117         value->type = value_type;
 118         switch (process_attr) {
 119         case LTTNG_PROCESS_ATTR_PROCESS_ID:
 120         case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID:
 121                 if (value_type != LTTNG_PROCESS_ATTR_VALUE_TYPE_PID) {
 122                         ERR("Invalid value type used for process ID process attribute");
 123                         ret = LTTNG_ERR_INVALID;
 124                         goto error;
 125                 }
 126                 value->value.pid =
 127                                 GET_INTEGRAL_COMM_VALUE(integral_value, pid_t);
 128                 break;
 129         case LTTNG_PROCESS_ATTR_USER_ID:
 130         case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID:
 131                 switch (value_type) {
 132                 case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 133                         value->value.uid = GET_INTEGRAL_COMM_VALUE(
 134                                         integral_value, uid_t);
 135                         break;
 136                 case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 137                         if (!name) {
 138                                 ret = LTTNG_ERR_INVALID;
 139                                 goto error;
 140                         }
 141
 142                         value->value.user_name = name;
 143                         name = NULL;
 144                         break;
 145                 default:
 146                         ERR("Invalid value type used for user ID process attribute");
 147                         ret = LTTNG_ERR_INVALID;
 148                         goto error;
 149                 }
 150                 break;
 151         case LTTNG_PROCESS_ATTR_GROUP_ID:
 152         case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID:
 153                 switch (value_type) {
 154                 case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 155                         value->value.gid = GET_INTEGRAL_COMM_VALUE(
 156                                         integral_value, gid_t);
 157                         break;
 158                 case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 159                         if (!name) {
 160                                 ret = LTTNG_ERR_INVALID;
 161                                 goto error;
 162                         }
 163
 164                         value->value.group_name = name;
 165                         name = NULL;
 166                         break;
 167                 default:
 168                         ERR("Invalid value type used for group ID process attribute");
 169                         ret = LTTNG_ERR_INVALID;
 170                         goto error;
 171                 }
 172                 break;
 173         default:
 174                 ret = LTTNG_ERR_INVALID_PROTOCOL;
 175                 goto error;
 176         }
 177
 178         *_value = value;
 179         value = NULL;
 180         free(name);
 181         return LTTNG_OK;
 182 error:
 183         free(name);
 184         process_attr_value_destroy(value);
 185         return ret;
 186 }
 187
 188 const char *lttng_process_attr_to_string(enum lttng_process_attr process_attr)
 189 {
 190         switch (process_attr) {
 191         case LTTNG_PROCESS_ATTR_PROCESS_ID:
 192                 return "process ID";
 193         case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID:
 194                 return "virtual process ID";
 195         case LTTNG_PROCESS_ATTR_USER_ID:
 196                 return "user ID";
 197         case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID:
 198                 return "virtual user ID";
 199         case LTTNG_PROCESS_ATTR_GROUP_ID:
 200                 return "group ID";
 201         case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID:
 202                 return "virtual group ID";
 203         default:
 204                 return "unknown process attribute";
 205         }
 206 }
 207
 208 static void process_attr_tracker_value_destructor(void *ptr)
 209 {
 210         struct process_attr_value *value = (typeof(value)) ptr;
 211
 212         process_attr_value_destroy(value);
 213 }
 214
 215 struct lttng_process_attr_values *lttng_process_attr_values_create(void)
 216 {
 217         struct lttng_process_attr_values *values = (lttng_process_attr_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 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 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 (process_attr_value *) 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                         .value = {},
 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 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 ssize_t lttng_process_attr_values_create_from_buffer(
 326                 enum lttng_domain_type domain,
 327                 enum lttng_process_attr process_attr,
 328                 const struct lttng_buffer_view *buffer_view,
 329                 struct lttng_process_attr_values **_values)
 330 {
 331         ssize_t offset;
 332         unsigned int i;
 333         struct lttng_process_attr_values *values;
 334         struct lttng_buffer_view header_view;
 335         const struct process_attr_tracker_values_comm_header *header;
 336
 337         values = lttng_process_attr_values_create();
 338         if (!values) {
 339                 goto error;
 340         }
 341
 342         header_view = lttng_buffer_view_from_view(
 343                         buffer_view, 0, sizeof(*header));
 344         if (!lttng_buffer_view_is_valid(&header_view)) {
 345                 goto error;
 346         }
 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 (!lttng_buffer_view_is_valid(&value_view)) {
 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                         if (!lttng_buffer_view_is_valid(&value_name_view)) {
 383                                 goto error;
 384                         }
 385
 386                         offset += value_name_view.size;
 387                 }
 388
 389                 ret_code = process_attr_value_from_comm(domain, process_attr,
 390                                 type, &value_comm->value.integral,
 391                                 &value_name_view, &value);
 392                 if (ret_code != LTTNG_OK) {
 393                         goto error;
 394                 }
 395
 396                 ret = lttng_dynamic_pointer_array_add_pointer(
 397                                 &values->array, value);
 398                 if (ret) {
 399                         process_attr_value_destroy(value);
 400                         goto error;
 401                 }
 402         }
 403
 404         *_values = values;
 405         return offset;
 406 error:
 407         lttng_process_attr_values_destroy(values);
 408         return -1;
 409 }
 410
 411 void lttng_process_attr_values_destroy(struct lttng_process_attr_values *values)
 412 {
 413         if (!values) {
 414                 return;
 415         }
 416         lttng_dynamic_pointer_array_reset(&values->array);
 417         free(values);
 418 }
 419
 420 struct process_attr_value *process_attr_value_copy(
 421                 const struct process_attr_value *value)
 422 {
 423         struct process_attr_value *new_value = NULL;
 424
 425         if (!value) {
 426                 goto end;
 427         }
 428
 429         new_value = (process_attr_value *) zmalloc(sizeof(*new_value));
 430         if (!new_value) {
 431                 goto end;
 432         }
 433         if (is_value_type_name(value->type)) {
 434                 const char *src =
 435                                 value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME ?
 436                                                 value->value.user_name :
 437                                                 value->value.group_name;
 438                 char **dst = value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME ?
 439                                              &new_value->value.user_name :
 440                                              &new_value->value.group_name;
 441
 442                 new_value->type = value->type;
 443                 *dst = strdup(src);
 444                 if (!*dst) {
 445                         goto error;
 446                 }
 447         } else {
 448                 *new_value = *value;
 449         }
 450 end:
 451         return new_value;
 452 error:
 453         free(new_value);
 454         return NULL;
 455 }
 456
 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 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 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 }