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 #include <type_traits>
  21
  22 struct process_attr_tracker_values_comm_header {
  23         uint32_t count;
  24 };
  25
  26 struct process_attr_tracker_value_comm {
  27         /* enum lttng_process_attr_value_type */
  28         int32_t type;
  29         union {
  30                 struct process_attr_integral_value_comm integral;
  31                 /* Includes the '\0' terminator. */
  32                 uint32_t name_len;
  33         } value;
  34 };
  35
  36 #define GET_INTEGRAL_COMM_VALUE(value_ptr, as_type)              \
  37         ((as_type)(std::is_signed<as_type>::value ?              \
  38                         (value_ptr)->u._signed : (value_ptr)->u._unsigned))
  39
  40 #define SET_INTEGRAL_COMM_VALUE(comm_value, from_value)                         \
  41         if (std::is_signed<decltype(from_value)>::value) {                      \
  42                 (comm_value)->u._signed =                                  \
  43                                 (typeof((comm_value)->u._signed)) from_value;   \
  44         } else {                                                           \
  45                 (comm_value)->u._unsigned =                                \
  46                                 (typeof((comm_value)->u._unsigned)) from_value; \
  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(
  57                 enum lttng_process_attr_value_type value_type)
  58 {
  59         return value_type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME ||
  60                value_type == LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME;
  61 }
  62
  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 = (process_attr_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 const char *lttng_process_attr_to_string(enum lttng_process_attr process_attr)
 188 {
 189         switch (process_attr) {
 190         case LTTNG_PROCESS_ATTR_PROCESS_ID:
 191                 return "process ID";
 192         case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID:
 193                 return "virtual process ID";
 194         case LTTNG_PROCESS_ATTR_USER_ID:
 195                 return "user ID";
 196         case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID:
 197                 return "virtual user ID";
 198         case LTTNG_PROCESS_ATTR_GROUP_ID:
 199                 return "group ID";
 200         case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID:
 201                 return "virtual group ID";
 202         default:
 203                 return "unknown process attribute";
 204         }
 205 }
 206
 207 static void process_attr_tracker_value_destructor(void *ptr)
 208 {
 209         struct process_attr_value *value = (typeof(value)) ptr;
 210
 211         process_attr_value_destroy(value);
 212 }
 213
 214 struct lttng_process_attr_values *lttng_process_attr_values_create(void)
 215 {
 216         struct lttng_process_attr_values *values = (lttng_process_attr_values *) zmalloc(sizeof(*values));
 217
 218         if (!values) {
 219                 goto end;
 220         }
 221
 222         lttng_dynamic_pointer_array_init(
 223                         &values->array, process_attr_tracker_value_destructor);
 224 end:
 225         return values;
 226 }
 227
 228 unsigned int _lttng_process_attr_values_get_count(
 229                 const struct lttng_process_attr_values *values)
 230 {
 231         return (unsigned int) lttng_dynamic_pointer_array_get_count(
 232                         &values->array);
 233 }
 234
 235 const struct process_attr_value *lttng_process_attr_tracker_values_get_at_index(
 236                 const struct lttng_process_attr_values *values,
 237                 unsigned int index)
 238 {
 239         return (process_attr_value *) lttng_dynamic_pointer_array_get_pointer(&values->array, index);
 240 }
 241
 242 static
 243 int process_attr_tracker_value_serialize(const struct process_attr_value *value,
 244                 struct lttng_dynamic_buffer *buffer)
 245 {
 246         int ret;
 247         struct process_attr_tracker_value_comm value_comm = {
 248                         .type = (int32_t) value->type,
 249         };
 250         const char *name = NULL;
 251
 252         switch (value->type) {
 253         case LTTNG_PROCESS_ATTR_VALUE_TYPE_PID:
 254                 SET_INTEGRAL_COMM_VALUE(
 255                                 &value_comm.value.integral, value->value.pid);
 256                 break;
 257         case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 258                 SET_INTEGRAL_COMM_VALUE(
 259                                 &value_comm.value.integral, value->value.uid);
 260                 break;
 261         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 262                 SET_INTEGRAL_COMM_VALUE(
 263                                 &value_comm.value.integral, value->value.gid);
 264                 break;
 265         case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 266                 name = value->value.user_name;
 267                 break;
 268         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 269                 name = value->value.group_name;
 270                 break;
 271         default:
 272                 abort();
 273         }
 274
 275         if (name) {
 276                 value_comm.value.name_len = strlen(name) + 1;
 277         }
 278
 279         ret = lttng_dynamic_buffer_append(
 280                         buffer, &value_comm, sizeof(value_comm));
 281         if (ret) {
 282                 goto end;
 283         }
 284
 285         if (name) {
 286                 ret = lttng_dynamic_buffer_append(
 287                                 buffer, name, value_comm.value.name_len);
 288         }
 289 end:
 290         return ret;
 291 }
 292
 293 int lttng_process_attr_values_serialize(
 294                 const struct lttng_process_attr_values *values,
 295                 struct lttng_dynamic_buffer *buffer)
 296 {
 297         int ret;
 298         unsigned int count, i;
 299         struct process_attr_tracker_values_comm_header header = {};
 300
 301         count = _lttng_process_attr_values_get_count(values);
 302         header.count = (uint32_t) count;
 303
 304         ret = lttng_dynamic_buffer_append(buffer, &header, sizeof(header));
 305         if (ret) {
 306                 goto end;
 307         }
 308
 309         for (i = 0; i < count; i++) {
 310                 const struct process_attr_value *value =
 311                                 lttng_process_attr_tracker_values_get_at_index(
 312                                                 values, i);
 313
 314                 ret = process_attr_tracker_value_serialize(value, buffer);
 315                 if (ret) {
 316                         goto end;
 317                 }
 318         }
 319 end:
 320         return ret;
 321 }
 322
 323 ssize_t lttng_process_attr_values_create_from_buffer(
 324                 enum lttng_domain_type domain,
 325                 enum lttng_process_attr process_attr,
 326                 const struct lttng_buffer_view *buffer_view,
 327                 struct lttng_process_attr_values **_values)
 328 {
 329         ssize_t offset;
 330         unsigned int i;
 331         struct lttng_process_attr_values *values;
 332         struct lttng_buffer_view header_view;
 333         const struct process_attr_tracker_values_comm_header *header;
 334
 335         values = lttng_process_attr_values_create();
 336         if (!values) {
 337                 goto error;
 338         }
 339
 340         header_view = lttng_buffer_view_from_view(
 341                         buffer_view, 0, sizeof(*header));
 342         if (!lttng_buffer_view_is_valid(&header_view)) {
 343                 goto error;
 344         }
 345
 346         offset = header_view.size;
 347         header = (typeof(header)) header_view.data;
 348
 349         /*
 350          * Check that the number of values is not absurdly large with respect to
 351          * the received buffer's size.
 352          */
 353         if (buffer_view->size <
 354                         header->count * sizeof(struct process_attr_tracker_value_comm)) {
 355                 goto error;
 356         }
 357         for (i = 0; i < (unsigned int) header->count; i++) {
 358                 int ret;
 359                 enum lttng_error_code ret_code;
 360                 const struct process_attr_tracker_value_comm *value_comm;
 361                 struct process_attr_value *value;
 362                 enum lttng_process_attr_value_type type;
 363                 struct lttng_buffer_view value_view;
 364                 struct lttng_buffer_view value_name_view = {};
 365
 366                 value_view = lttng_buffer_view_from_view(
 367                                 buffer_view, offset, sizeof(*value_comm));
 368                 if (!lttng_buffer_view_is_valid(&value_view)) {
 369                         goto error;
 370                 }
 371
 372                 offset += value_view.size;
 373                 value_comm = (typeof(value_comm)) value_view.data;
 374                 type = (typeof(type)) value_comm->type;
 375
 376                 if (is_value_type_name(type)) {
 377                         value_name_view = lttng_buffer_view_from_view(
 378                                         buffer_view, offset,
 379                                         value_comm->value.name_len);
 380                         if (!lttng_buffer_view_is_valid(&value_name_view)) {
 381                                 goto error;
 382                         }
 383
 384                         offset += value_name_view.size;
 385                 }
 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 void lttng_process_attr_values_destroy(struct lttng_process_attr_values *values)
 410 {
 411         if (!values) {
 412                 return;
 413         }
 414         lttng_dynamic_pointer_array_reset(&values->array);
 415         free(values);
 416 }
 417
 418 struct process_attr_value *process_attr_value_copy(
 419                 const struct process_attr_value *value)
 420 {
 421         struct process_attr_value *new_value = NULL;
 422
 423         if (!value) {
 424                 goto end;
 425         }
 426
 427         new_value = (process_attr_value *) zmalloc(sizeof(*new_value));
 428         if (!new_value) {
 429                 goto end;
 430         }
 431         if (is_value_type_name(value->type)) {
 432                 const char *src =
 433                                 value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME ?
 434                                                 value->value.user_name :
 435                                                 value->value.group_name;
 436                 char **dst = value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME ?
 437                                              &new_value->value.user_name :
 438                                              &new_value->value.group_name;
 439
 440                 new_value->type = value->type;
 441                 *dst = strdup(src);
 442                 if (!*dst) {
 443                         goto error;
 444                 }
 445         } else {
 446                 *new_value = *value;
 447         }
 448 end:
 449         return new_value;
 450 error:
 451         free(new_value);
 452         return NULL;
 453 }
 454
 455 unsigned long process_attr_value_hash(const struct process_attr_value *a)
 456 {
 457         unsigned long hash = hash_key_ulong((void *) a->type, lttng_ht_seed);
 458
 459         switch (a->type) {
 460         case LTTNG_PROCESS_ATTR_VALUE_TYPE_PID:
 461                 hash ^= hash_key_ulong((void *) (unsigned long) a->value.pid,
 462                                 lttng_ht_seed);
 463                 break;
 464         case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 465                 hash ^= hash_key_ulong((void *) (unsigned long) a->value.uid,
 466                                 lttng_ht_seed);
 467                 break;
 468         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 469                 hash ^= hash_key_ulong((void *) (unsigned long) a->value.gid,
 470                                 lttng_ht_seed);
 471                 break;
 472         case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 473                 hash ^= hash_key_str(a->value.user_name, lttng_ht_seed);
 474                 break;
 475         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 476                 hash ^= hash_key_str(a->value.group_name, lttng_ht_seed);
 477                 break;
 478         default:
 479                 abort();
 480         }
 481
 482         return hash;
 483 }
 484
 485 bool process_attr_tracker_value_equal(const struct process_attr_value *a,
 486                 const struct process_attr_value *b)
 487 {
 488         if (a->type != b->type) {
 489                 return false;
 490         }
 491         switch (a->type) {
 492         case LTTNG_PROCESS_ATTR_VALUE_TYPE_PID:
 493                 return a->value.pid == b->value.pid;
 494         case LTTNG_PROCESS_ATTR_VALUE_TYPE_UID:
 495                 return a->value.uid == b->value.uid;
 496         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GID:
 497                 return a->value.gid == b->value.gid;
 498         case LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME:
 499                 return !strcmp(a->value.user_name, b->value.user_name);
 500         case LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME:
 501                 return !strcmp(a->value.group_name, b->value.group_name);
 502         default:
 503                 abort();
 504         }
 505 }
 506
 507 void process_attr_value_destroy(struct process_attr_value *value)
 508 {
 509         if (!value) {
 510                 return;
 511         }
 512         if (is_value_type_name(value->type)) {
 513                 free(value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME ?
 514                                                 value->value.user_name :
 515                                                 value->value.group_name);
 516         }
 517         free(value);
 518 }