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.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 #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         };
 251         const char *name = NULL;
 252
 253         switch (value->type) {
 254         case LTTNG_PROCESS_ATTR_VALUE_TYPE_PID:
 255                 SET_INTEGRAL_COMM_VALUE(
 256                                 &value_comm.value.integral, value->value.pid);
 257                 break;
 258         case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 259                 SET_INTEGRAL_COMM_VALUE(
 260                                 &value_comm.value.integral, value->value.uid);
 261                 break;
 262         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 263                 SET_INTEGRAL_COMM_VALUE(
 264                                 &value_comm.value.integral, value->value.gid);
 265                 break;
 266         case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 267                 name = value->value.user_name;
 268                 break;
 269         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 270                 name = value->value.group_name;
 271                 break;
 272         default:
 273                 abort();
 274         }
 275
 276         if (name) {
 277                 value_comm.value.name_len = strlen(name) + 1;
 278         }
 279
 280         ret = lttng_dynamic_buffer_append(
 281                         buffer, &value_comm, sizeof(value_comm));
 282         if (ret) {
 283                 goto end;
 284         }
 285
 286         if (name) {
 287                 ret = lttng_dynamic_buffer_append(
 288                                 buffer, name, value_comm.value.name_len);
 289         }
 290 end:
 291         return ret;
 292 }
 293
 294 int lttng_process_attr_values_serialize(
 295                 const struct lttng_process_attr_values *values,
 296                 struct lttng_dynamic_buffer *buffer)
 297 {
 298         int ret;
 299         unsigned int count, i;
 300         struct process_attr_tracker_values_comm_header header = {};
 301
 302         count = _lttng_process_attr_values_get_count(values);
 303         header.count = (uint32_t) count;
 304
 305         ret = lttng_dynamic_buffer_append(buffer, &header, sizeof(header));
 306         if (ret) {
 307                 goto end;
 308         }
 309
 310         for (i = 0; i < count; i++) {
 311                 const struct process_attr_value *value =
 312                                 lttng_process_attr_tracker_values_get_at_index(
 313                                                 values, i);
 314
 315                 ret = process_attr_tracker_value_serialize(value, buffer);
 316                 if (ret) {
 317                         goto end;
 318                 }
 319         }
 320 end:
 321         return ret;
 322 }
 323
 324 ssize_t lttng_process_attr_values_create_from_buffer(
 325                 enum lttng_domain_type domain,
 326                 enum lttng_process_attr process_attr,
 327                 const struct lttng_buffer_view *buffer_view,
 328                 struct lttng_process_attr_values **_values)
 329 {
 330         ssize_t offset;
 331         unsigned int i;
 332         struct lttng_process_attr_values *values;
 333         struct lttng_buffer_view header_view;
 334         const struct process_attr_tracker_values_comm_header *header;
 335
 336         values = lttng_process_attr_values_create();
 337         if (!values) {
 338                 goto error;
 339         }
 340
 341         header_view = lttng_buffer_view_from_view(
 342                         buffer_view, 0, sizeof(*header));
 343         if (!lttng_buffer_view_is_valid(&header_view)) {
 344                 goto error;
 345         }
 346
 347         offset = header_view.size;
 348         header = (typeof(header)) header_view.data;
 349
 350         /*
 351          * Check that the number of values is not absurdly large with respect to
 352          * the received buffer's size.
 353          */
 354         if (buffer_view->size <
 355                         header->count * sizeof(struct process_attr_tracker_value_comm)) {
 356                 goto error;
 357         }
 358         for (i = 0; i < (unsigned int) header->count; i++) {
 359                 int ret;
 360                 enum lttng_error_code ret_code;
 361                 const struct process_attr_tracker_value_comm *value_comm;
 362                 struct process_attr_value *value;
 363                 enum lttng_process_attr_value_type type;
 364                 struct lttng_buffer_view value_view;
 365                 struct lttng_buffer_view value_name_view = {};
 366
 367                 value_view = lttng_buffer_view_from_view(
 368                                 buffer_view, offset, sizeof(*value_comm));
 369                 if (!lttng_buffer_view_is_valid(&value_view)) {
 370                         goto error;
 371                 }
 372
 373                 offset += value_view.size;
 374                 value_comm = (typeof(value_comm)) value_view.data;
 375                 type = (typeof(type)) value_comm->type;
 376
 377                 if (is_value_type_name(type)) {
 378                         value_name_view = lttng_buffer_view_from_view(
 379                                         buffer_view, offset,
 380                                         value_comm->value.name_len);
 381                         if (!lttng_buffer_view_is_valid(&value_name_view)) {
 382                                 goto error;
 383                         }
 384
 385                         offset += value_name_view.size;
 386                 }
 387
 388                 ret_code = process_attr_value_from_comm(domain, process_attr,
 389                                 type, &value_comm->value.integral,
 390                                 &value_name_view, &value);
 391                 if (ret_code != LTTNG_OK) {
 392                         goto error;
 393                 }
 394
 395                 ret = lttng_dynamic_pointer_array_add_pointer(
 396                                 &values->array, value);
 397                 if (ret) {
 398                         process_attr_value_destroy(value);
 399                         goto error;
 400                 }
 401         }
 402
 403         *_values = values;
 404         return offset;
 405 error:
 406         lttng_process_attr_values_destroy(values);
 407         return -1;
 408 }
 409
 410 void lttng_process_attr_values_destroy(struct lttng_process_attr_values *values)
 411 {
 412         if (!values) {
 413                 return;
 414         }
 415         lttng_dynamic_pointer_array_reset(&values->array);
 416         free(values);
 417 }
 418
 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 = (process_attr_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 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 bool process_attr_tracker_value_equal(const struct process_attr_value *a,
 487                 const struct process_attr_value *b)
 488 {
 489         if (a->type != b->type) {
 490                 return false;
 491         }
 492         switch (a->type) {
 493         case LTTNG_PROCESS_ATTR_VALUE_TYPE_PID:
 494                 return a->value.pid == b->value.pid;
 495         case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 496                 return a->value.uid == b->value.uid;
 497         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 498                 return a->value.gid == b->value.gid;
 499         case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 500                 return !strcmp(a->value.user_name, b->value.user_name);
 501         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 502                 return !strcmp(a->value.group_name, b->value.group_name);
 503         default:
 504                 abort();
 505         }
 506 }
 507
 508 void process_attr_value_destroy(struct process_attr_value *value)
 509 {
 510         if (!value) {
 511                 return;
 512         }
 513         if (is_value_type_name(value->type)) {
 514                 free(value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME ?
 515                                                 value->value.user_name :
 516                                                 value->value.group_name);
 517         }
 518         free(value);
 519 }