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) &&
 107                         (!value_view || value_view->size == 0)) {
 108                 ret = LTTNG_ERR_INVALID_PROTOCOL;
 109                 goto error;
 110         } else if (!is_value_type_name(value_type) && value_view &&
 111                         value_view->size != 0) {
 112                 ret = LTTNG_ERR_INVALID_PROTOCOL;
 113                 goto error;
 114         }
 115
 116         value->type = value_type;
 117         switch (process_attr) {
 118         case LTTNG_PROCESS_ATTR_PROCESS_ID:
 119         case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID:
 120                 if (value_type != LTTNG_PROCESS_ATTR_VALUE_TYPE_PID) {
 121                         ERR("Invalid value type used for process ID process attribute");
 122                         ret = LTTNG_ERR_INVALID;
 123                         goto error;
 124                 }
 125                 value->value.pid =
 126                                 GET_INTEGRAL_COMM_VALUE(integral_value, pid_t);
 127                 break;
 128         case LTTNG_PROCESS_ATTR_USER_ID:
 129         case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID:
 130                 switch (value_type) {
 131                 case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 132                         value->value.uid = GET_INTEGRAL_COMM_VALUE(
 133                                         integral_value, uid_t);
 134                         break;
 135                 case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 136                         if (!name) {
 137                                 ret = LTTNG_ERR_INVALID;
 138                                 goto error;
 139                         }
 140
 141                         value->value.user_name = name;
 142                         name = NULL;
 143                         break;
 144                 default:
 145                         ERR("Invalid value type used for user ID process attribute");
 146                         ret = LTTNG_ERR_INVALID;
 147                         goto error;
 148                 }
 149                 break;
 150         case LTTNG_PROCESS_ATTR_GROUP_ID:
 151         case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID:
 152                 switch (value_type) {
 153                 case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 154                         value->value.gid = GET_INTEGRAL_COMM_VALUE(
 155                                         integral_value, gid_t);
 156                         break;
 157                 case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 158                         if (!name) {
 159                                 ret = LTTNG_ERR_INVALID;
 160                                 goto error;
 161                         }
 162
 163                         value->value.group_name = name;
 164                         name = NULL;
 165                         break;
 166                 default:
 167                         ERR("Invalid value type used for group ID process attribute");
 168                         ret = LTTNG_ERR_INVALID;
 169                         goto error;
 170                 }
 171                 break;
 172         default:
 173                 ret = LTTNG_ERR_INVALID_PROTOCOL;
 174                 goto error;
 175         }
 176
 177         *_value = value;
 178         value = NULL;
 179         free(name);
 180         return LTTNG_OK;
 181 error:
 182         free(name);
 183         process_attr_value_destroy(value);
 184         return ret;
 185 }
 186
 187 LTTNG_HIDDEN
 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 LTTNG_HIDDEN
 216 struct lttng_process_attr_values *lttng_process_attr_values_create(void)
 217 {
 218         struct lttng_process_attr_values *values = zmalloc(sizeof(*values));
 219
 220         if (!values) {
 221                 goto end;
 222         }
 223
 224         lttng_dynamic_pointer_array_init(
 225                         &values->array, process_attr_tracker_value_destructor);
 226 end:
 227         return values;
 228 }
 229
 230 LTTNG_HIDDEN
 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 LTTNG_HIDDEN
 239 const struct process_attr_value *lttng_process_attr_tracker_values_get_at_index(
 240                 const struct lttng_process_attr_values *values,
 241                 unsigned int index)
 242 {
 243         return lttng_dynamic_pointer_array_get_pointer(&values->array, index);
 244 }
 245
 246 static
 247 int process_attr_tracker_value_serialize(const struct process_attr_value *value,
 248                 struct lttng_dynamic_buffer *buffer)
 249 {
 250         int ret;
 251         struct process_attr_tracker_value_comm value_comm = {
 252                         .type = (int32_t) value->type,
 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 LTTNG_HIDDEN
 298 int lttng_process_attr_values_serialize(
 299                 const struct lttng_process_attr_values *values,
 300                 struct lttng_dynamic_buffer *buffer)
 301 {
 302         int ret;
 303         unsigned int count, i;
 304         struct process_attr_tracker_values_comm_header header = {};
 305
 306         count = _lttng_process_attr_values_get_count(values);
 307         header.count = (uint32_t) count;
 308
 309         ret = lttng_dynamic_buffer_append(buffer, &header, sizeof(header));
 310         if (ret) {
 311                 goto end;
 312         }
 313
 314         for (i = 0; i < count; i++) {
 315                 const struct process_attr_value *value =
 316                                 lttng_process_attr_tracker_values_get_at_index(
 317                                                 values, i);
 318
 319                 ret = process_attr_tracker_value_serialize(value, buffer);
 320                 if (ret) {
 321                         goto end;
 322                 }
 323         }
 324 end:
 325         return ret;
 326 }
 327
 328 LTTNG_HIDDEN
 329 ssize_t lttng_process_attr_values_create_from_buffer(
 330                 enum lttng_domain_type domain,
 331                 enum lttng_process_attr process_attr,
 332                 const struct lttng_buffer_view *buffer_view,
 333                 struct lttng_process_attr_values **_values)
 334 {
 335         ssize_t offset;
 336         unsigned int i;
 337         struct lttng_process_attr_values *values;
 338         struct lttng_buffer_view header_view;
 339         const struct process_attr_tracker_values_comm_header *header;
 340
 341         values = lttng_process_attr_values_create();
 342         if (!values) {
 343                 goto error;
 344         }
 345
 346         header_view = lttng_buffer_view_from_view(
 347                         buffer_view, 0, sizeof(*header));
 348         if (!header_view.data) {
 349                 goto error;
 350         }
 351         offset = header_view.size;
 352         header = (typeof(header)) header_view.data;
 353
 354         /*
 355          * Check that the number of values is not absurdly large with respect to
 356          * the received buffer's size.
 357          */
 358         if (buffer_view->size <
 359                         header->count * sizeof(struct process_attr_tracker_value_comm)) {
 360                 goto error;
 361         }
 362         for (i = 0; i < (unsigned int) header->count; i++) {
 363                 int ret;
 364                 enum lttng_error_code ret_code;
 365                 const struct process_attr_tracker_value_comm *value_comm;
 366                 struct process_attr_value *value;
 367                 enum lttng_process_attr_value_type type;
 368                 struct lttng_buffer_view value_view;
 369                 struct lttng_buffer_view value_name_view = {};
 370
 371                 value_view = lttng_buffer_view_from_view(
 372                                 buffer_view, offset, sizeof(*value_comm));
 373                 if (!value_view.data) {
 374                         goto error;
 375                 }
 376
 377                 offset += value_view.size;
 378                 value_comm = (typeof(value_comm)) value_view.data;
 379                 type = (typeof(type)) value_comm->type;
 380
 381                 if (is_value_type_name(type)) {
 382                         value_name_view = lttng_buffer_view_from_view(
 383                                         buffer_view, offset,
 384                                         value_comm->value.name_len);
 385                         offset += value_name_view.size;
 386                 }
 387                 ret_code = process_attr_value_from_comm(domain, process_attr,
 388                                 type, &value_comm->value.integral,
 389                                 &value_name_view, &value);
 390                 if (ret_code != LTTNG_OK) {
 391                         goto error;
 392                 }
 393
 394                 ret = lttng_dynamic_pointer_array_add_pointer(
 395                                 &values->array, value);
 396                 if (ret) {
 397                         process_attr_value_destroy(value);
 398                         goto error;
 399                 }
 400         }
 401
 402         *_values = values;
 403         return offset;
 404 error:
 405         lttng_process_attr_values_destroy(values);
 406         return -1;
 407 }
 408
 409 LTTNG_HIDDEN
 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 LTTNG_HIDDEN
 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 = 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 LTTNG_HIDDEN
 458 unsigned long process_attr_value_hash(const struct process_attr_value *a)
 459 {
 460         unsigned long hash = hash_key_ulong((void *) a->type, lttng_ht_seed);
 461
 462         switch (a->type) {
 463         case LTTNG_PROCESS_ATTR_VALUE_TYPE_PID:
 464                 hash ^= hash_key_ulong((void *) (unsigned long) a->value.pid,
 465                                 lttng_ht_seed);
 466                 break;
 467         case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 468                 hash ^= hash_key_ulong((void *) (unsigned long) a->value.uid,
 469                                 lttng_ht_seed);
 470                 break;
 471         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 472                 hash ^= hash_key_ulong((void *) (unsigned long) a->value.gid,
 473                                 lttng_ht_seed);
 474                 break;
 475         case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 476                 hash ^= hash_key_str(a->value.user_name, lttng_ht_seed);
 477                 break;
 478         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 479                 hash ^= hash_key_str(a->value.group_name, lttng_ht_seed);
 480                 break;
 481         default:
 482                 abort();
 483         }
 484
 485         return hash;
 486 }
 487
 488 LTTNG_HIDDEN
 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 LTTNG_HIDDEN
 512 void process_attr_value_destroy(struct process_attr_value *value)
 513 {
 514         if (!value) {
 515                 return;
 516         }
 517         if (is_value_type_name(value->type)) {
 518                 free(value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME ?
 519                                                 value->value.user_name :
 520                                                 value->value.group_name);
 521         }
 522         free(value);
 523 }