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 <common/dynamic-array.hpp>
  10 #include <common/error.hpp>
  11 #include <common/hashtable/hashtable.hpp>
  12 #include <common/hashtable/utils.hpp>
  13 #include <common/tracker.hpp>
  14
  15 #include <lttng/domain.h>
  16 #include <lttng/lttng-error.h>
  17 #include <lttng/tracker.h>
  18
  19 #include <stdbool.h>
  20 #include <type_traits>
  21
  22 namespace {
  23 struct process_attr_tracker_values_comm_header {
  24         uint32_t count;
  25 } LTTNG_PACKED;
  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 } LTTNG_PACKED;
  36 } /* namespace */
  37
  38 #define GET_INTEGRAL_COMM_VALUE(value_ptr, as_type)                           \
  39         ((as_type) (std::is_signed<as_type>::value ? (value_ptr)->u._signed : \
  40                                                      (value_ptr)->u._unsigned))
  41
  42 #define SET_INTEGRAL_COMM_VALUE(comm_value, val)                                       \
  43         if (std::is_signed<typeof(val)>::value) {                                      \
  44                 (comm_value)->u._signed = (typeof((comm_value)->u._signed)) (val);     \
  45         } else {                                                                       \
  46                 (comm_value)->u._unsigned = (typeof((comm_value)->u._unsigned)) (val); \
  47         }
  48
  49 static inline bool is_virtual_process_attr(enum lttng_process_attr process_attr)
  50 {
  51         return process_attr == LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID ||
  52                 process_attr == LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID ||
  53                 process_attr == LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID;
  54 }
  55
  56 static inline bool is_value_type_name(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
  63 process_attr_value_from_comm(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 = nullptr;
  71         enum lttng_error_code ret = LTTNG_OK;
  72         struct process_attr_value *value = zmalloc<process_attr_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) && domain != LTTNG_DOMAIN_KERNEL) {
  98                 ERR("Non-virtual process attributes can only be used in the kernel domain");
  99                 ret = LTTNG_ERR_UNSUPPORTED_DOMAIN;
 100                 goto error;
 101         }
 102
 103         /* Only expect a payload for name value types. */
 104         if (is_value_type_name(value_type) && (!value_view || value_view->size == 0)) {
 105                 ret = LTTNG_ERR_INVALID_PROTOCOL;
 106                 goto error;
 107         } else if (!is_value_type_name(value_type) && value_view && value_view->size != 0) {
 108                 ret = LTTNG_ERR_INVALID_PROTOCOL;
 109                 goto error;
 110         }
 111
 112         value->type = value_type;
 113         switch (process_attr) {
 114         case LTTNG_PROCESS_ATTR_PROCESS_ID:
 115         case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID:
 116                 if (value_type != LTTNG_PROCESS_ATTR_VALUE_TYPE_PID) {
 117                         ERR("Invalid value type used for process ID process attribute");
 118                         ret = LTTNG_ERR_INVALID;
 119                         goto error;
 120                 }
 121                 value->value.pid = GET_INTEGRAL_COMM_VALUE(integral_value, pid_t);
 122                 break;
 123         case LTTNG_PROCESS_ATTR_USER_ID:
 124         case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID:
 125                 switch (value_type) {
 126                 case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 127                         value->value.uid = GET_INTEGRAL_COMM_VALUE(integral_value, uid_t);
 128                         break;
 129                 case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 130                         if (!name) {
 131                                 ret = LTTNG_ERR_INVALID;
 132                                 goto error;
 133                         }
 134
 135                         value->value.user_name = name;
 136                         name = nullptr;
 137                         break;
 138                 default:
 139                         ERR("Invalid value type used for user ID process attribute");
 140                         ret = LTTNG_ERR_INVALID;
 141                         goto error;
 142                 }
 143                 break;
 144         case LTTNG_PROCESS_ATTR_GROUP_ID:
 145         case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID:
 146                 switch (value_type) {
 147                 case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 148                         value->value.gid = GET_INTEGRAL_COMM_VALUE(integral_value, gid_t);
 149                         break;
 150                 case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 151                         if (!name) {
 152                                 ret = LTTNG_ERR_INVALID;
 153                                 goto error;
 154                         }
 155
 156                         value->value.group_name = name;
 157                         name = nullptr;
 158                         break;
 159                 default:
 160                         ERR("Invalid value type used for group ID process attribute");
 161                         ret = LTTNG_ERR_INVALID;
 162                         goto error;
 163                 }
 164                 break;
 165         default:
 166                 ret = LTTNG_ERR_INVALID_PROTOCOL;
 167                 goto error;
 168         }
 169
 170         *_value = value;
 171         value = nullptr;
 172         free(name);
 173         return LTTNG_OK;
 174 error:
 175         free(name);
 176         process_attr_value_destroy(value);
 177         return ret;
 178 }
 179
 180 const char *lttng_process_attr_to_string(enum lttng_process_attr process_attr)
 181 {
 182         switch (process_attr) {
 183         case LTTNG_PROCESS_ATTR_PROCESS_ID:
 184                 return "process ID";
 185         case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID:
 186                 return "virtual process ID";
 187         case LTTNG_PROCESS_ATTR_USER_ID:
 188                 return "user ID";
 189         case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID:
 190                 return "virtual user ID";
 191         case LTTNG_PROCESS_ATTR_GROUP_ID:
 192                 return "group ID";
 193         case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID:
 194                 return "virtual group ID";
 195         default:
 196                 return "unknown process attribute";
 197         }
 198 }
 199
 200 static void process_attr_tracker_value_destructor(void *ptr)
 201 {
 202         struct process_attr_value *value = (typeof(value)) ptr;
 203
 204         process_attr_value_destroy(value);
 205 }
 206
 207 struct lttng_process_attr_values *lttng_process_attr_values_create()
 208 {
 209         struct lttng_process_attr_values *values = zmalloc<lttng_process_attr_values>();
 210
 211         if (!values) {
 212                 goto end;
 213         }
 214
 215         lttng_dynamic_pointer_array_init(&values->array, process_attr_tracker_value_destructor);
 216 end:
 217         return values;
 218 }
 219
 220 unsigned int _lttng_process_attr_values_get_count(const struct lttng_process_attr_values *values)
 221 {
 222         return (unsigned int) lttng_dynamic_pointer_array_get_count(&values->array);
 223 }
 224
 225 const struct process_attr_value *
 226 lttng_process_attr_tracker_values_get_at_index(const struct lttng_process_attr_values *values,
 227                                                unsigned int index)
 228 {
 229         return (process_attr_value *) lttng_dynamic_pointer_array_get_pointer(&values->array,
 230                                                                               index);
 231 }
 232
 233 static int process_attr_tracker_value_serialize(const struct process_attr_value *value,
 234                                                 struct lttng_dynamic_buffer *buffer)
 235 {
 236         int ret;
 237         struct process_attr_tracker_value_comm value_comm = {
 238                 .type = (int32_t) value->type,
 239                 .value = {},
 240         };
 241         const char *name = nullptr;
 242
 243         switch (value->type) {
 244         case LTTNG_PROCESS_ATTR_VALUE_TYPE_PID:
 245                 SET_INTEGRAL_COMM_VALUE(&value_comm.value.integral, value->value.pid);
 246                 break;
 247         case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 248                 SET_INTEGRAL_COMM_VALUE(&value_comm.value.integral, value->value.uid);
 249                 break;
 250         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 251                 SET_INTEGRAL_COMM_VALUE(&value_comm.value.integral, value->value.gid);
 252                 break;
 253         case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 254                 name = value->value.user_name;
 255                 break;
 256         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 257                 name = value->value.group_name;
 258                 break;
 259         default:
 260                 abort();
 261         }
 262
 263         if (name) {
 264                 value_comm.value.name_len = strlen(name) + 1;
 265         }
 266
 267         ret = lttng_dynamic_buffer_append(buffer, &value_comm, sizeof(value_comm));
 268         if (ret) {
 269                 goto end;
 270         }
 271
 272         if (name) {
 273                 ret = lttng_dynamic_buffer_append(buffer, name, value_comm.value.name_len);
 274         }
 275 end:
 276         return ret;
 277 }
 278
 279 int lttng_process_attr_values_serialize(const struct lttng_process_attr_values *values,
 280                                         struct lttng_dynamic_buffer *buffer)
 281 {
 282         int ret;
 283         unsigned int count, i;
 284         struct process_attr_tracker_values_comm_header header = {};
 285
 286         count = _lttng_process_attr_values_get_count(values);
 287         header.count = (uint32_t) count;
 288
 289         ret = lttng_dynamic_buffer_append(buffer, &header, sizeof(header));
 290         if (ret) {
 291                 goto end;
 292         }
 293
 294         for (i = 0; i < count; i++) {
 295                 const struct process_attr_value *value =
 296                         lttng_process_attr_tracker_values_get_at_index(values, i);
 297
 298                 ret = process_attr_tracker_value_serialize(value, buffer);
 299                 if (ret) {
 300                         goto end;
 301                 }
 302         }
 303 end:
 304         return ret;
 305 }
 306
 307 ssize_t lttng_process_attr_values_create_from_buffer(enum lttng_domain_type domain,
 308                                                      enum lttng_process_attr process_attr,
 309                                                      const struct lttng_buffer_view *buffer_view,
 310                                                      struct lttng_process_attr_values **_values)
 311 {
 312         ssize_t offset;
 313         unsigned int i;
 314         struct lttng_process_attr_values *values;
 315         struct lttng_buffer_view header_view;
 316         const struct process_attr_tracker_values_comm_header *header;
 317
 318         values = lttng_process_attr_values_create();
 319         if (!values) {
 320                 goto error;
 321         }
 322
 323         header_view = lttng_buffer_view_from_view(buffer_view, 0, sizeof(*header));
 324         if (!lttng_buffer_view_is_valid(&header_view)) {
 325                 goto error;
 326         }
 327
 328         offset = header_view.size;
 329         header = (typeof(header)) header_view.data;
 330
 331         /*
 332          * Check that the number of values is not absurdly large with respect to
 333          * the received buffer's size.
 334          */
 335         if (buffer_view->size < header->count * sizeof(struct process_attr_tracker_value_comm)) {
 336                 goto error;
 337         }
 338         for (i = 0; i < (unsigned int) header->count; i++) {
 339                 int ret;
 340                 enum lttng_error_code ret_code;
 341                 const struct process_attr_tracker_value_comm *value_comm;
 342                 struct process_attr_value *value;
 343                 enum lttng_process_attr_value_type type;
 344                 struct lttng_buffer_view value_view;
 345                 struct lttng_buffer_view value_name_view = {};
 346
 347                 value_view = lttng_buffer_view_from_view(buffer_view, offset, sizeof(*value_comm));
 348                 if (!lttng_buffer_view_is_valid(&value_view)) {
 349                         goto error;
 350                 }
 351
 352                 offset += value_view.size;
 353                 value_comm = (typeof(value_comm)) value_view.data;
 354                 type = (typeof(type)) value_comm->type;
 355
 356                 if (is_value_type_name(type)) {
 357                         value_name_view = lttng_buffer_view_from_view(
 358                                 buffer_view, offset, value_comm->value.name_len);
 359                         if (!lttng_buffer_view_is_valid(&value_name_view)) {
 360                                 goto error;
 361                         }
 362
 363                         offset += value_name_view.size;
 364                 }
 365
 366                 ret_code = process_attr_value_from_comm(domain,
 367                                                         process_attr,
 368                                                         type,
 369                                                         &value_comm->value.integral,
 370                                                         &value_name_view,
 371                                                         &value);
 372                 if (ret_code != LTTNG_OK) {
 373                         goto error;
 374                 }
 375
 376                 ret = lttng_dynamic_pointer_array_add_pointer(&values->array, value);
 377                 if (ret) {
 378                         process_attr_value_destroy(value);
 379                         goto error;
 380                 }
 381         }
 382
 383         *_values = values;
 384         return offset;
 385 error:
 386         lttng_process_attr_values_destroy(values);
 387         return -1;
 388 }
 389
 390 void lttng_process_attr_values_destroy(struct lttng_process_attr_values *values)
 391 {
 392         if (!values) {
 393                 return;
 394         }
 395         lttng_dynamic_pointer_array_reset(&values->array);
 396         free(values);
 397 }
 398
 399 struct process_attr_value *process_attr_value_copy(const struct process_attr_value *value)
 400 {
 401         struct process_attr_value *new_value = nullptr;
 402
 403         if (!value) {
 404                 goto end;
 405         }
 406
 407         new_value = zmalloc<process_attr_value>();
 408         if (!new_value) {
 409                 goto end;
 410         }
 411         if (is_value_type_name(value->type)) {
 412                 const char *src = value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME ?
 413                         value->value.user_name :
 414                         value->value.group_name;
 415                 char **dst = value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME ?
 416                         &new_value->value.user_name :
 417                         &new_value->value.group_name;
 418
 419                 new_value->type = value->type;
 420                 *dst = strdup(src);
 421                 if (!*dst) {
 422                         goto error;
 423                 }
 424         } else {
 425                 *new_value = *value;
 426         }
 427 end:
 428         return new_value;
 429 error:
 430         free(new_value);
 431         return nullptr;
 432 }
 433
 434 unsigned long process_attr_value_hash(const struct process_attr_value *a)
 435 {
 436         unsigned long hash = hash_key_ulong((void *) a->type, lttng_ht_seed);
 437
 438         switch (a->type) {
 439         case LTTNG_PROCESS_ATTR_VALUE_TYPE_PID:
 440                 hash ^= hash_key_ulong((void *) (unsigned long) a->value.pid, lttng_ht_seed);
 441                 break;
 442         case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 443                 hash ^= hash_key_ulong((void *) (unsigned long) a->value.uid, lttng_ht_seed);
 444                 break;
 445         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 446                 hash ^= hash_key_ulong((void *) (unsigned long) a->value.gid, lttng_ht_seed);
 447                 break;
 448         case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 449                 hash ^= hash_key_str(a->value.user_name, lttng_ht_seed);
 450                 break;
 451         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 452                 hash ^= hash_key_str(a->value.group_name, lttng_ht_seed);
 453                 break;
 454         default:
 455                 abort();
 456         }
 457
 458         return hash;
 459 }
 460
 461 bool process_attr_tracker_value_equal(const struct process_attr_value *a,
 462                                       const struct process_attr_value *b)
 463 {
 464         if (a->type != b->type) {
 465                 return false;
 466         }
 467         switch (a->type) {
 468         case LTTNG_PROCESS_ATTR_VALUE_TYPE_PID:
 469                 return a->value.pid == b->value.pid;
 470         case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 471                 return a->value.uid == b->value.uid;
 472         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 473                 return a->value.gid == b->value.gid;
 474         case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 475                 return !strcmp(a->value.user_name, b->value.user_name);
 476         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 477                 return !strcmp(a->value.group_name, b->value.group_name);
 478         default:
 479                 abort();
 480         }
 481 }
 482
 483 void process_attr_value_destroy(struct process_attr_value *value)
 484 {
 485         if (!value) {
 486                 return;
 487         }
 488         if (is_value_type_name(value->type)) {
 489                 free(value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME ?
 490                              value->value.user_name :
 491                              value->value.group_name);
 492         }
 493         free(value);
 494 }