| 1 | /* |
| 2 | * Copyright (C) 2020 Jonathan Rajotte <jonathan.rajotte-julien@efficios.com> |
| 3 | * |
| 4 | * SPDX-License-Identifier: LGPL-2.1-only |
| 5 | * |
| 6 | */ |
| 7 | |
| 8 | #include <assert.h> |
| 9 | #include <common/error.h> |
| 10 | #include <common/macros.h> |
| 11 | #include <lttng/condition/condition-internal.h> |
| 12 | #include <lttng/condition/event-rule-internal.h> |
| 13 | #include <lttng/condition/event-rule.h> |
| 14 | #include <lttng/event-rule/event-rule-internal.h> |
| 15 | #include <stdbool.h> |
| 16 | |
| 17 | #define IS_EVENT_RULE_CONDITION(condition) \ |
| 18 | (lttng_condition_get_type(condition) == \ |
| 19 | LTTNG_CONDITION_TYPE_EVENT_RULE_HIT) |
| 20 | |
| 21 | static bool is_event_rule_evaluation(const struct lttng_evaluation *evaluation) |
| 22 | { |
| 23 | enum lttng_condition_type type = lttng_evaluation_get_type(evaluation); |
| 24 | |
| 25 | return type == LTTNG_CONDITION_TYPE_EVENT_RULE_HIT; |
| 26 | } |
| 27 | |
| 28 | static bool lttng_condition_event_rule_validate( |
| 29 | const struct lttng_condition *condition); |
| 30 | static int lttng_condition_event_rule_serialize( |
| 31 | const struct lttng_condition *condition, |
| 32 | struct lttng_payload *payload); |
| 33 | static bool lttng_condition_event_rule_is_equal( |
| 34 | const struct lttng_condition *_a, |
| 35 | const struct lttng_condition *_b); |
| 36 | static void lttng_condition_event_rule_destroy( |
| 37 | struct lttng_condition *condition); |
| 38 | |
| 39 | static bool lttng_condition_event_rule_validate( |
| 40 | const struct lttng_condition *condition) |
| 41 | { |
| 42 | bool valid = false; |
| 43 | struct lttng_condition_event_rule *event_rule; |
| 44 | |
| 45 | if (!condition) { |
| 46 | goto end; |
| 47 | } |
| 48 | |
| 49 | event_rule = container_of( |
| 50 | condition, struct lttng_condition_event_rule, parent); |
| 51 | if (!event_rule->rule) { |
| 52 | ERR("Invalid event rule condition: a rule must be set."); |
| 53 | goto end; |
| 54 | } |
| 55 | |
| 56 | valid = lttng_event_rule_validate(event_rule->rule); |
| 57 | end: |
| 58 | return valid; |
| 59 | } |
| 60 | |
| 61 | static int lttng_condition_event_rule_serialize( |
| 62 | const struct lttng_condition *condition, |
| 63 | struct lttng_payload *payload) |
| 64 | { |
| 65 | int ret; |
| 66 | size_t header_offset, size_before_payload; |
| 67 | struct lttng_condition_event_rule *event_rule; |
| 68 | struct lttng_condition_event_rule_comm event_rule_comm = {}; |
| 69 | struct lttng_condition_event_rule_comm *header = NULL; |
| 70 | |
| 71 | if (!condition || !IS_EVENT_RULE_CONDITION(condition)) { |
| 72 | ret = -1; |
| 73 | goto end; |
| 74 | } |
| 75 | |
| 76 | DBG("Serializing event rule condition"); |
| 77 | event_rule = container_of( |
| 78 | condition, struct lttng_condition_event_rule, parent); |
| 79 | |
| 80 | header_offset = payload->buffer.size; |
| 81 | ret = lttng_dynamic_buffer_append(&payload->buffer, &event_rule_comm, |
| 82 | sizeof(event_rule_comm)); |
| 83 | if (ret) { |
| 84 | goto end; |
| 85 | } |
| 86 | |
| 87 | size_before_payload = payload->buffer.size; |
| 88 | ret = lttng_event_rule_serialize(event_rule->rule, payload); |
| 89 | if (ret) { |
| 90 | goto end; |
| 91 | } |
| 92 | |
| 93 | /* Update payload size. */ |
| 94 | header = (struct lttng_condition_event_rule_comm *) |
| 95 | ((char *) payload->buffer.data + header_offset); |
| 96 | header->event_rule_length = payload->buffer.size - size_before_payload; |
| 97 | |
| 98 | end: |
| 99 | return ret; |
| 100 | } |
| 101 | |
| 102 | static bool lttng_condition_event_rule_is_equal( |
| 103 | const struct lttng_condition *_a, |
| 104 | const struct lttng_condition *_b) |
| 105 | { |
| 106 | bool is_equal = false; |
| 107 | struct lttng_condition_event_rule *a, *b; |
| 108 | |
| 109 | a = container_of(_a, struct lttng_condition_event_rule, parent); |
| 110 | b = container_of(_b, struct lttng_condition_event_rule, parent); |
| 111 | |
| 112 | /* Both event rules must be set or both must be unset. */ |
| 113 | if ((a->rule && !b->rule) || (!a->rule && b->rule)) { |
| 114 | WARN("Comparing event_rule conditions with uninitialized rule"); |
| 115 | goto end; |
| 116 | } |
| 117 | |
| 118 | is_equal = lttng_event_rule_is_equal(a->rule, b->rule); |
| 119 | end: |
| 120 | return is_equal; |
| 121 | } |
| 122 | |
| 123 | static void lttng_condition_event_rule_destroy( |
| 124 | struct lttng_condition *condition) |
| 125 | { |
| 126 | struct lttng_condition_event_rule *event_rule; |
| 127 | |
| 128 | event_rule = container_of( |
| 129 | condition, struct lttng_condition_event_rule, parent); |
| 130 | |
| 131 | lttng_event_rule_put(event_rule->rule); |
| 132 | free(event_rule); |
| 133 | } |
| 134 | |
| 135 | struct lttng_condition *lttng_condition_event_rule_create( |
| 136 | struct lttng_event_rule *rule) |
| 137 | { |
| 138 | struct lttng_condition *parent = NULL; |
| 139 | struct lttng_condition_event_rule *condition = NULL; |
| 140 | |
| 141 | if (!rule) { |
| 142 | goto end; |
| 143 | } |
| 144 | |
| 145 | condition = zmalloc(sizeof(struct lttng_condition_event_rule)); |
| 146 | if (!condition) { |
| 147 | return NULL; |
| 148 | } |
| 149 | |
| 150 | lttng_condition_init(&condition->parent, |
| 151 | LTTNG_CONDITION_TYPE_EVENT_RULE_HIT); |
| 152 | condition->parent.validate = lttng_condition_event_rule_validate, |
| 153 | condition->parent.serialize = lttng_condition_event_rule_serialize, |
| 154 | condition->parent.equal = lttng_condition_event_rule_is_equal, |
| 155 | condition->parent.destroy = lttng_condition_event_rule_destroy, |
| 156 | |
| 157 | lttng_event_rule_get(rule); |
| 158 | condition->rule = rule; |
| 159 | rule = NULL; |
| 160 | |
| 161 | parent = &condition->parent; |
| 162 | end: |
| 163 | return parent; |
| 164 | } |
| 165 | |
| 166 | LTTNG_HIDDEN |
| 167 | ssize_t lttng_condition_event_rule_create_from_payload( |
| 168 | struct lttng_payload_view *view, |
| 169 | struct lttng_condition **_condition) |
| 170 | { |
| 171 | ssize_t offset, event_rule_length; |
| 172 | struct lttng_condition *condition = NULL; |
| 173 | struct lttng_event_rule *event_rule = NULL; |
| 174 | const struct lttng_condition_event_rule_comm *header; |
| 175 | const struct lttng_payload_view header_view = |
| 176 | lttng_payload_view_from_view( |
| 177 | view, 0, sizeof(*header)); |
| 178 | |
| 179 | if (!view || !_condition) { |
| 180 | goto error; |
| 181 | } |
| 182 | |
| 183 | if (!lttng_payload_view_is_valid(&header_view)) { |
| 184 | ERR("Failed to initialize from malformed event rule condition: buffer too short to contain header"); |
| 185 | goto error; |
| 186 | } |
| 187 | |
| 188 | header = (const struct lttng_condition_event_rule_comm *) |
| 189 | header_view.buffer.data; |
| 190 | offset = sizeof(*header); |
| 191 | |
| 192 | /* lttng_event_rule payload. */ |
| 193 | { |
| 194 | struct lttng_payload_view event_rule_view = |
| 195 | lttng_payload_view_from_view(view, offset, -1); |
| 196 | |
| 197 | event_rule_length = lttng_event_rule_create_from_payload( |
| 198 | &event_rule_view, &event_rule); |
| 199 | } |
| 200 | |
| 201 | if (event_rule_length < 0 || !event_rule) { |
| 202 | goto error; |
| 203 | } |
| 204 | |
| 205 | if ((size_t) header->event_rule_length != event_rule_length) { |
| 206 | goto error; |
| 207 | } |
| 208 | |
| 209 | /* Move to the end of the payload. */ |
| 210 | offset += header->event_rule_length; |
| 211 | |
| 212 | /* Acquires a reference to the event rule. */ |
| 213 | condition = lttng_condition_event_rule_create(event_rule); |
| 214 | if (!condition) { |
| 215 | goto error; |
| 216 | } |
| 217 | |
| 218 | *_condition = condition; |
| 219 | condition = NULL; |
| 220 | goto end; |
| 221 | |
| 222 | error: |
| 223 | offset = -1; |
| 224 | |
| 225 | end: |
| 226 | lttng_event_rule_put(event_rule); |
| 227 | lttng_condition_put(condition); |
| 228 | return offset; |
| 229 | } |
| 230 | |
| 231 | LTTNG_HIDDEN |
| 232 | enum lttng_condition_status lttng_condition_event_rule_borrow_rule_mutable( |
| 233 | const struct lttng_condition *condition, |
| 234 | struct lttng_event_rule **rule) |
| 235 | { |
| 236 | struct lttng_condition_event_rule *event_rule; |
| 237 | enum lttng_condition_status status = LTTNG_CONDITION_STATUS_OK; |
| 238 | |
| 239 | if (!condition || !IS_EVENT_RULE_CONDITION(condition) || !rule) { |
| 240 | status = LTTNG_CONDITION_STATUS_INVALID; |
| 241 | goto end; |
| 242 | } |
| 243 | |
| 244 | event_rule = container_of( |
| 245 | condition, struct lttng_condition_event_rule, parent); |
| 246 | if (!event_rule->rule) { |
| 247 | status = LTTNG_CONDITION_STATUS_UNSET; |
| 248 | goto end; |
| 249 | } |
| 250 | |
| 251 | *rule = event_rule->rule; |
| 252 | end: |
| 253 | return status; |
| 254 | } |
| 255 | |
| 256 | enum lttng_condition_status lttng_condition_event_rule_get_rule( |
| 257 | const struct lttng_condition *condition, |
| 258 | const struct lttng_event_rule **rule) |
| 259 | { |
| 260 | struct lttng_event_rule *mutable_rule = NULL; |
| 261 | const enum lttng_condition_status status = |
| 262 | lttng_condition_event_rule_borrow_rule_mutable( |
| 263 | condition, &mutable_rule); |
| 264 | |
| 265 | *rule = mutable_rule; |
| 266 | return status; |
| 267 | } |
| 268 | |
| 269 | LTTNG_HIDDEN |
| 270 | ssize_t lttng_evaluation_event_rule_create_from_payload( |
| 271 | struct lttng_payload_view *view, |
| 272 | struct lttng_evaluation **_evaluation) |
| 273 | { |
| 274 | ssize_t ret, offset = 0; |
| 275 | const char *trigger_name; |
| 276 | struct lttng_evaluation *evaluation = NULL; |
| 277 | const struct lttng_evaluation_event_rule_comm *header; |
| 278 | const struct lttng_payload_view header_view = |
| 279 | lttng_payload_view_from_view( |
| 280 | view, 0, sizeof(*header)); |
| 281 | |
| 282 | if (!_evaluation) { |
| 283 | ret = -1; |
| 284 | goto error; |
| 285 | } |
| 286 | |
| 287 | if (!lttng_payload_view_is_valid(&header_view)) { |
| 288 | ERR("Failed to initialize from malformed event rule evaluation: buffer too short to contain header"); |
| 289 | ret = -1; |
| 290 | goto error; |
| 291 | } |
| 292 | |
| 293 | header = (typeof(header)) header_view.buffer.data; |
| 294 | |
| 295 | /* Map the originating trigger's name. */ |
| 296 | offset += sizeof(*header); |
| 297 | { |
| 298 | struct lttng_payload_view current_view = |
| 299 | lttng_payload_view_from_view(view, offset, |
| 300 | header->trigger_name_length); |
| 301 | |
| 302 | if (!lttng_payload_view_is_valid(¤t_view)) { |
| 303 | ERR("Failed to initialize from malformed event rule evaluation: buffer too short to contain trigger name"); |
| 304 | ret = -1; |
| 305 | goto error; |
| 306 | } |
| 307 | |
| 308 | trigger_name = current_view.buffer.data; |
| 309 | if (!lttng_buffer_view_contains_string(¤t_view.buffer, |
| 310 | trigger_name, header->trigger_name_length)) { |
| 311 | ERR("Failed to initialize from malformed event rule evaluation: invalid trigger name"); |
| 312 | ret = -1; |
| 313 | goto error; |
| 314 | } |
| 315 | } |
| 316 | |
| 317 | offset += header->trigger_name_length; |
| 318 | |
| 319 | evaluation = lttng_evaluation_event_rule_create(trigger_name); |
| 320 | if (!evaluation) { |
| 321 | ret = -1; |
| 322 | goto error; |
| 323 | } |
| 324 | |
| 325 | *_evaluation = evaluation; |
| 326 | evaluation = NULL; |
| 327 | ret = offset; |
| 328 | |
| 329 | error: |
| 330 | lttng_evaluation_destroy(evaluation); |
| 331 | return ret; |
| 332 | } |
| 333 | |
| 334 | static int lttng_evaluation_event_rule_serialize( |
| 335 | const struct lttng_evaluation *evaluation, |
| 336 | struct lttng_payload *payload) |
| 337 | { |
| 338 | int ret = 0; |
| 339 | struct lttng_evaluation_event_rule *hit; |
| 340 | struct lttng_evaluation_event_rule_comm comm; |
| 341 | |
| 342 | hit = container_of( |
| 343 | evaluation, struct lttng_evaluation_event_rule, parent); |
| 344 | |
| 345 | assert(hit->name); |
| 346 | comm.trigger_name_length = strlen(hit->name) + 1; |
| 347 | |
| 348 | ret = lttng_dynamic_buffer_append( |
| 349 | &payload->buffer, &comm, sizeof(comm)); |
| 350 | if (ret) { |
| 351 | goto end; |
| 352 | } |
| 353 | |
| 354 | ret = lttng_dynamic_buffer_append( |
| 355 | &payload->buffer, hit->name, comm.trigger_name_length); |
| 356 | end: |
| 357 | return ret; |
| 358 | } |
| 359 | |
| 360 | static void lttng_evaluation_event_rule_destroy( |
| 361 | struct lttng_evaluation *evaluation) |
| 362 | { |
| 363 | struct lttng_evaluation_event_rule *hit; |
| 364 | |
| 365 | hit = container_of( |
| 366 | evaluation, struct lttng_evaluation_event_rule, parent); |
| 367 | free(hit->name); |
| 368 | free(hit); |
| 369 | } |
| 370 | |
| 371 | LTTNG_HIDDEN |
| 372 | struct lttng_evaluation *lttng_evaluation_event_rule_create( |
| 373 | const char *trigger_name) |
| 374 | { |
| 375 | struct lttng_evaluation_event_rule *hit; |
| 376 | struct lttng_evaluation *evaluation = NULL; |
| 377 | |
| 378 | hit = zmalloc(sizeof(struct lttng_evaluation_event_rule)); |
| 379 | if (!hit) { |
| 380 | goto end; |
| 381 | } |
| 382 | |
| 383 | hit->name = strdup(trigger_name); |
| 384 | if (!hit->name) { |
| 385 | goto end; |
| 386 | } |
| 387 | |
| 388 | hit->parent.type = LTTNG_CONDITION_TYPE_EVENT_RULE_HIT; |
| 389 | hit->parent.serialize = lttng_evaluation_event_rule_serialize; |
| 390 | hit->parent.destroy = lttng_evaluation_event_rule_destroy; |
| 391 | |
| 392 | evaluation = &hit->parent; |
| 393 | hit = NULL; |
| 394 | |
| 395 | end: |
| 396 | if (hit) { |
| 397 | lttng_evaluation_event_rule_destroy(&hit->parent); |
| 398 | } |
| 399 | |
| 400 | return evaluation; |
| 401 | } |
| 402 | |
| 403 | enum lttng_evaluation_status lttng_evaluation_event_rule_get_trigger_name( |
| 404 | const struct lttng_evaluation *evaluation, const char **name) |
| 405 | { |
| 406 | struct lttng_evaluation_event_rule *hit; |
| 407 | enum lttng_evaluation_status status = LTTNG_EVALUATION_STATUS_OK; |
| 408 | |
| 409 | if (!evaluation || !is_event_rule_evaluation(evaluation) || !name) { |
| 410 | status = LTTNG_EVALUATION_STATUS_INVALID; |
| 411 | goto end; |
| 412 | } |
| 413 | |
| 414 | hit = container_of( |
| 415 | evaluation, struct lttng_evaluation_event_rule, parent); |
| 416 | *name = hit->name; |
| 417 | end: |
| 418 | return status; |
| 419 | } |