| 1 | /* |
| 2 | * Copyright (C) 2017 - Jérémie Galarneau <jeremie.galarneau@efficios.com> |
| 3 | * |
| 4 | * This library is free software; you can redistribute it and/or modify it |
| 5 | * under the terms of the GNU Lesser General Public License, version 2.1 only, |
| 6 | * as published by the Free Software Foundation. |
| 7 | * |
| 8 | * This library is distributed in the hope that it will be useful, but WITHOUT |
| 9 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 10 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License |
| 11 | * for more details. |
| 12 | * |
| 13 | * You should have received a copy of the GNU Lesser General Public License |
| 14 | * along with this library; if not, write to the Free Software Foundation, |
| 15 | * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 16 | */ |
| 17 | |
| 18 | #include <lttng/condition/condition-internal.h> |
| 19 | #include <lttng/condition/event-rule-internal.h> |
| 20 | #include <lttng/event-rule/event-rule-internal.h> |
| 21 | #include <common/macros.h> |
| 22 | #include <common/error.h> |
| 23 | #include <assert.h> |
| 24 | #include <stdbool.h> |
| 25 | |
| 26 | #define IS_EVENT_RULE_CONDITION(condition) ( \ |
| 27 | lttng_condition_get_type(condition) == LTTNG_CONDITION_TYPE_EVENT_RULE_HIT \ |
| 28 | ) |
| 29 | |
| 30 | static |
| 31 | bool is_event_rule_evaluation(const struct lttng_evaluation *evaluation) |
| 32 | { |
| 33 | enum lttng_condition_type type = lttng_evaluation_get_type(evaluation); |
| 34 | |
| 35 | return type == LTTNG_CONDITION_TYPE_EVENT_RULE_HIT; |
| 36 | } |
| 37 | |
| 38 | |
| 39 | static |
| 40 | bool lttng_condition_event_rule_validate( |
| 41 | const struct lttng_condition *condition); |
| 42 | static |
| 43 | int lttng_condition_event_rule_serialize( |
| 44 | const struct lttng_condition *condition, |
| 45 | struct lttng_dynamic_buffer *buf, |
| 46 | int *fd_to_send); |
| 47 | static |
| 48 | bool lttng_condition_event_rule_is_equal(const struct lttng_condition *_a, |
| 49 | const struct lttng_condition *_b); |
| 50 | static |
| 51 | void lttng_condition_event_rule_destroy( |
| 52 | struct lttng_condition *condition); |
| 53 | |
| 54 | |
| 55 | static |
| 56 | bool lttng_condition_event_rule_validate( |
| 57 | const struct lttng_condition *condition) |
| 58 | { |
| 59 | bool valid = false; |
| 60 | struct lttng_condition_event_rule *event_rule; |
| 61 | |
| 62 | if (!condition) { |
| 63 | goto end; |
| 64 | } |
| 65 | |
| 66 | event_rule = container_of(condition, |
| 67 | struct lttng_condition_event_rule, parent); |
| 68 | if (!event_rule->rule) { |
| 69 | ERR("Invalid session event_rule condition: a rule must be set."); |
| 70 | goto end; |
| 71 | } |
| 72 | |
| 73 | valid = lttng_event_rule_validate(event_rule->rule); |
| 74 | end: |
| 75 | return valid; |
| 76 | } |
| 77 | |
| 78 | static |
| 79 | int lttng_condition_event_rule_serialize( |
| 80 | const struct lttng_condition *condition, |
| 81 | struct lttng_dynamic_buffer *buf, |
| 82 | int *fd_to_send) |
| 83 | { |
| 84 | int ret; |
| 85 | size_t header_offset, size_before_payload; |
| 86 | struct lttng_condition_event_rule *event_rule; |
| 87 | struct lttng_condition_event_rule_comm event_rule_comm = { 0 }; |
| 88 | struct lttng_condition_event_rule_comm *header; |
| 89 | |
| 90 | if (!condition || !IS_EVENT_RULE_CONDITION(condition)) { |
| 91 | ret = -1; |
| 92 | goto end; |
| 93 | } |
| 94 | |
| 95 | DBG("Serializing event rule condition"); |
| 96 | event_rule = container_of(condition, struct lttng_condition_event_rule, |
| 97 | parent); |
| 98 | |
| 99 | header_offset = buf->size; |
| 100 | ret = lttng_dynamic_buffer_append(buf, &event_rule_comm, |
| 101 | sizeof(event_rule_comm)); |
| 102 | if (ret) { |
| 103 | goto end; |
| 104 | } |
| 105 | |
| 106 | size_before_payload = buf->size; |
| 107 | ret = lttng_event_rule_serialize(event_rule->rule, buf, fd_to_send); |
| 108 | if (ret) { |
| 109 | goto end; |
| 110 | } |
| 111 | |
| 112 | /* Update payload size */ |
| 113 | header = (struct lttng_condition_event_rule_comm *) ((char *) buf->data + header_offset); |
| 114 | header->length = buf->size - size_before_payload; |
| 115 | |
| 116 | end: |
| 117 | return ret; |
| 118 | } |
| 119 | |
| 120 | static |
| 121 | bool lttng_condition_event_rule_is_equal(const struct lttng_condition *_a, |
| 122 | const struct lttng_condition *_b) |
| 123 | { |
| 124 | bool is_equal = false; |
| 125 | struct lttng_condition_event_rule *a, *b; |
| 126 | |
| 127 | a = container_of(_a, struct lttng_condition_event_rule, parent); |
| 128 | b = container_of(_b, struct lttng_condition_event_rule, parent); |
| 129 | |
| 130 | /* Both session names must be set or both must be unset. */ |
| 131 | if ((a->rule && !b->rule) || |
| 132 | (!a->rule && b->rule)) { |
| 133 | WARN("Comparing session event_rule conditions with uninitialized rule."); |
| 134 | goto end; |
| 135 | } |
| 136 | |
| 137 | is_equal = lttng_event_rule_is_equal(a->rule, b->rule); |
| 138 | end: |
| 139 | return is_equal; |
| 140 | } |
| 141 | |
| 142 | static |
| 143 | void lttng_condition_event_rule_destroy( |
| 144 | struct lttng_condition *condition) |
| 145 | { |
| 146 | struct lttng_condition_event_rule *event_rule; |
| 147 | |
| 148 | event_rule = container_of(condition, |
| 149 | struct lttng_condition_event_rule, parent); |
| 150 | |
| 151 | |
| 152 | lttng_event_rule_destroy(event_rule->rule); |
| 153 | free(event_rule); |
| 154 | } |
| 155 | |
| 156 | struct lttng_condition *lttng_condition_event_rule_create( |
| 157 | struct lttng_event_rule *rule) |
| 158 | { |
| 159 | struct lttng_condition *parent = NULL; |
| 160 | struct lttng_condition_event_rule *condition = NULL; |
| 161 | |
| 162 | if (!rule) { |
| 163 | goto end; |
| 164 | } |
| 165 | |
| 166 | condition = zmalloc(sizeof(struct lttng_condition_event_rule)); |
| 167 | if (!condition) { |
| 168 | return NULL; |
| 169 | } |
| 170 | |
| 171 | lttng_condition_init(&condition->parent, LTTNG_CONDITION_TYPE_EVENT_RULE_HIT); |
| 172 | condition->parent.validate = lttng_condition_event_rule_validate, |
| 173 | condition->parent.serialize = lttng_condition_event_rule_serialize, |
| 174 | condition->parent.equal = lttng_condition_event_rule_is_equal, |
| 175 | condition->parent.destroy = lttng_condition_event_rule_destroy, |
| 176 | |
| 177 | condition->rule = rule; |
| 178 | parent = &condition->parent; |
| 179 | end: |
| 180 | return parent; |
| 181 | } |
| 182 | |
| 183 | LTTNG_HIDDEN |
| 184 | ssize_t lttng_condition_event_rule_create_from_buffer( |
| 185 | const struct lttng_buffer_view *view, |
| 186 | struct lttng_condition **_condition) |
| 187 | { |
| 188 | ssize_t offset, event_rule_size; |
| 189 | const struct lttng_condition_event_rule_comm *comm; |
| 190 | struct lttng_condition *condition = NULL; |
| 191 | struct lttng_event_rule *event_rule = NULL; |
| 192 | struct lttng_buffer_view event_rule_view; |
| 193 | |
| 194 | if (!view || !_condition) { |
| 195 | goto error; |
| 196 | } |
| 197 | |
| 198 | if (view->size < sizeof(*comm)) { |
| 199 | ERR("Failed to initialize from malformed event rule condition: buffer too short to contain header"); |
| 200 | goto error; |
| 201 | } |
| 202 | |
| 203 | comm = (const struct lttng_condition_event_rule_comm *) view->data; |
| 204 | offset = sizeof(*comm); |
| 205 | |
| 206 | /* Struct lttng_event_rule */ |
| 207 | event_rule_view = lttng_buffer_view_from_view(view, offset, -1); |
| 208 | event_rule_size = lttng_event_rule_create_from_buffer(&event_rule_view, &event_rule); |
| 209 | if (event_rule_size < 0 || !event_rule) { |
| 210 | goto error; |
| 211 | } |
| 212 | |
| 213 | if ((size_t) comm->length != event_rule_size) { |
| 214 | goto error; |
| 215 | } |
| 216 | |
| 217 | /* Move to the end */ |
| 218 | offset += comm->length; |
| 219 | |
| 220 | condition = lttng_condition_event_rule_create(event_rule); |
| 221 | if (!condition) { |
| 222 | goto error; |
| 223 | } |
| 224 | |
| 225 | /* Ownership passed on condition event rule create */ |
| 226 | event_rule = NULL; |
| 227 | |
| 228 | *_condition = condition; |
| 229 | condition = NULL; |
| 230 | goto end; |
| 231 | |
| 232 | error: |
| 233 | offset = -1; |
| 234 | |
| 235 | end: |
| 236 | lttng_event_rule_destroy(event_rule); |
| 237 | lttng_condition_destroy(condition); |
| 238 | return offset; |
| 239 | } |
| 240 | |
| 241 | LTTNG_HIDDEN |
| 242 | enum lttng_condition_status |
| 243 | lttng_condition_event_rule_get_rule_no_const( |
| 244 | const struct lttng_condition *condition, |
| 245 | struct lttng_event_rule **rule) |
| 246 | { |
| 247 | struct lttng_condition_event_rule *event_rule; |
| 248 | enum lttng_condition_status status = LTTNG_CONDITION_STATUS_OK; |
| 249 | |
| 250 | if (!condition || !IS_EVENT_RULE_CONDITION(condition) || !rule) { |
| 251 | status = LTTNG_CONDITION_STATUS_INVALID; |
| 252 | goto end; |
| 253 | } |
| 254 | |
| 255 | event_rule = container_of(condition, struct lttng_condition_event_rule, |
| 256 | parent); |
| 257 | if (!event_rule->rule) { |
| 258 | status = LTTNG_CONDITION_STATUS_UNSET; |
| 259 | goto end; |
| 260 | } |
| 261 | *rule = event_rule->rule; |
| 262 | end: |
| 263 | return status; |
| 264 | } |
| 265 | |
| 266 | enum lttng_condition_status |
| 267 | lttng_condition_event_rule_get_rule( |
| 268 | const struct lttng_condition *condition, |
| 269 | const struct lttng_event_rule **rule) |
| 270 | { |
| 271 | struct lttng_event_rule *no_const_rule = NULL; |
| 272 | enum lttng_condition_status status; |
| 273 | |
| 274 | status = lttng_condition_event_rule_get_rule_no_const(condition, &no_const_rule); |
| 275 | *rule = no_const_rule; |
| 276 | return status; |
| 277 | } |
| 278 | |
| 279 | LTTNG_HIDDEN |
| 280 | ssize_t lttng_evaluation_event_rule_create_from_buffer( |
| 281 | const struct lttng_buffer_view *view, |
| 282 | struct lttng_evaluation **_evaluation) |
| 283 | { |
| 284 | ssize_t ret, offset = 0; |
| 285 | const char *name; |
| 286 | struct lttng_evaluation *evaluation = NULL; |
| 287 | const struct lttng_evaluation_event_rule_comm *comm = |
| 288 | (const struct lttng_evaluation_event_rule_comm *) view->data; |
| 289 | struct lttng_buffer_view current_view; |
| 290 | |
| 291 | if (!_evaluation) { |
| 292 | ret = -1; |
| 293 | goto error; |
| 294 | } |
| 295 | |
| 296 | if (view->size < sizeof(*comm)) { |
| 297 | ret = -1; |
| 298 | goto error; |
| 299 | } |
| 300 | |
| 301 | /* Map the name, view of the payload */ |
| 302 | offset += sizeof(*comm); |
| 303 | current_view = lttng_buffer_view_from_view(view, offset, comm->trigger_name_length); |
| 304 | name = current_view.data; |
| 305 | if (!name) { |
| 306 | ret = -1; |
| 307 | goto error; |
| 308 | } |
| 309 | |
| 310 | if (comm->trigger_name_length == 1 || |
| 311 | name[comm->trigger_name_length - 1] != '\0' || |
| 312 | strlen(name) != comm->trigger_name_length - 1) { |
| 313 | /* |
| 314 | * Check that the name is not NULL, is NULL-terminated, and |
| 315 | * does not contain a NULL before the last byte. |
| 316 | */ |
| 317 | ret = -1; |
| 318 | goto error; |
| 319 | } |
| 320 | |
| 321 | offset += comm->trigger_name_length; |
| 322 | |
| 323 | evaluation = lttng_evaluation_event_rule_create(name); |
| 324 | if (!evaluation) { |
| 325 | ret = -1; |
| 326 | goto error; |
| 327 | } |
| 328 | |
| 329 | *_evaluation = evaluation; |
| 330 | evaluation = NULL; |
| 331 | ret = offset; |
| 332 | |
| 333 | error: |
| 334 | lttng_evaluation_destroy(evaluation); |
| 335 | return ret; |
| 336 | } |
| 337 | |
| 338 | static |
| 339 | int lttng_evaluation_event_rule_serialize( |
| 340 | const struct lttng_evaluation *evaluation, |
| 341 | struct lttng_dynamic_buffer *buf) |
| 342 | { |
| 343 | int ret = 0; |
| 344 | struct lttng_evaluation_event_rule *hit; |
| 345 | struct lttng_evaluation_event_rule_comm comm; |
| 346 | |
| 347 | hit = container_of(evaluation, struct lttng_evaluation_event_rule, |
| 348 | parent); |
| 349 | comm.trigger_name_length = strlen(hit->name) + 1; |
| 350 | ret = lttng_dynamic_buffer_append(buf, &comm, sizeof(comm)); |
| 351 | if (ret) { |
| 352 | goto end; |
| 353 | } |
| 354 | ret = lttng_dynamic_buffer_append(buf, hit->name, comm.trigger_name_length); |
| 355 | end: |
| 356 | return ret; |
| 357 | } |
| 358 | |
| 359 | static |
| 360 | void lttng_evaluation_event_rule_destroy( |
| 361 | struct lttng_evaluation *evaluation) |
| 362 | { |
| 363 | struct lttng_evaluation_event_rule *hit; |
| 364 | |
| 365 | hit = container_of(evaluation, struct lttng_evaluation_event_rule, |
| 366 | parent); |
| 367 | free(hit->name); |
| 368 | free(hit); |
| 369 | } |
| 370 | |
| 371 | LTTNG_HIDDEN |
| 372 | struct lttng_evaluation *lttng_evaluation_event_rule_create(const char *trigger_name) |
| 373 | { |
| 374 | struct lttng_evaluation_event_rule *hit; |
| 375 | |
| 376 | hit = zmalloc(sizeof(struct lttng_evaluation_event_rule)); |
| 377 | if (!hit) { |
| 378 | goto end; |
| 379 | } |
| 380 | |
| 381 | /* TODO errir handling */ |
| 382 | hit->name = strdup(trigger_name); |
| 383 | |
| 384 | hit->parent.type = LTTNG_CONDITION_TYPE_EVENT_RULE_HIT; |
| 385 | hit->parent.serialize = lttng_evaluation_event_rule_serialize; |
| 386 | hit->parent.destroy = lttng_evaluation_event_rule_destroy; |
| 387 | end: |
| 388 | return &hit->parent; |
| 389 | } |
| 390 | |
| 391 | enum lttng_evaluation_status |
| 392 | lttng_evaluation_event_rule_get_trigger_name( |
| 393 | const struct lttng_evaluation *evaluation, |
| 394 | const char **name) |
| 395 | { |
| 396 | struct lttng_evaluation_event_rule *hit; |
| 397 | enum lttng_evaluation_status status = LTTNG_EVALUATION_STATUS_OK; |
| 398 | |
| 399 | if (!evaluation || !is_event_rule_evaluation(evaluation) || !name) { |
| 400 | status = LTTNG_EVALUATION_STATUS_INVALID; |
| 401 | goto end; |
| 402 | } |
| 403 | |
| 404 | hit = container_of(evaluation, struct lttng_evaluation_event_rule, |
| 405 | parent); |
| 406 | *name = hit->name; |
| 407 | end: |
| 408 | return status; |
| 409 | } |