src/common/event-rule/event-rule.c

   1 /*
   2  * Copyright (C) 2019 Jonathan Rajotte
   3  * <jonathan.rajotte-julien@efficios.com>
   4  *
   5  * SPDX-License-Identifier: LGPL-2.1-only
   6  *
   7  */
   8
   9 #include <assert.h>
  10 #include <common/error.h>
  11 #include <common/macros.h>
  12 #include <common/payload.h>
  13 #include <common/payload-view.h>
  14 #include <common/hashtable/hashtable.h>
  15 #include <common/hashtable/utils.h>
  16 #include <lttng/event-rule/event-rule-internal.h>
  17 #include <lttng/event-rule/kprobe-internal.h>
  18 #include <lttng/event-rule/syscall-internal.h>
  19 #include <lttng/event-rule/tracepoint-internal.h>
  20 #include <lttng/event-rule/uprobe-internal.h>
  21 #include <stdbool.h>
  22
  23 enum lttng_event_rule_type lttng_event_rule_get_type(
  24                 const struct lttng_event_rule *event_rule)
  25 {
  26         return event_rule ? event_rule->type : LTTNG_EVENT_RULE_TYPE_UNKNOWN;
  27 }
  28
  29 LTTNG_HIDDEN
  30 enum lttng_domain_type lttng_event_rule_get_domain_type(
  31                 const struct lttng_event_rule *event_rule)
  32 {
  33         enum lttng_domain_type domain_type = LTTNG_DOMAIN_NONE;
  34
  35         switch (lttng_event_rule_get_type(event_rule)) {
  36         case LTTNG_EVENT_RULE_TYPE_TRACEPOINT:
  37         {
  38                 enum lttng_event_rule_status status;
  39                 status = lttng_event_rule_tracepoint_get_domain_type(event_rule, &domain_type);
  40                 assert(status == LTTNG_EVENT_RULE_STATUS_OK);
  41                 break;
  42         }
  43         case LTTNG_EVENT_RULE_TYPE_SYSCALL:
  44         case LTTNG_EVENT_RULE_TYPE_KPROBE:
  45         case LTTNG_EVENT_RULE_TYPE_KRETPROBE:
  46         case LTTNG_EVENT_RULE_TYPE_UPROBE:
  47                 domain_type = LTTNG_DOMAIN_KERNEL;
  48                 break;
  49         case LTTNG_EVENT_RULE_TYPE_UNKNOWN:
  50                 domain_type = LTTNG_DOMAIN_NONE;
  51                 break;
  52         }
  53
  54         return domain_type;
  55 }
  56
  57 static void lttng_event_rule_release(struct urcu_ref *ref)
  58 {
  59         struct lttng_event_rule *event_rule =
  60                         container_of(ref, typeof(*event_rule), ref);
  61
  62         assert(event_rule->destroy);
  63         event_rule->destroy(event_rule);
  64 }
  65
  66 void lttng_event_rule_destroy(struct lttng_event_rule *event_rule)
  67 {
  68         lttng_event_rule_put(event_rule);
  69 }
  70
  71 LTTNG_HIDDEN
  72 bool lttng_event_rule_validate(const struct lttng_event_rule *event_rule)
  73 {
  74         bool valid;
  75
  76         if (!event_rule) {
  77                 valid = false;
  78                 goto end;
  79         }
  80
  81         if (!event_rule->validate) {
  82                 /* Sub-class guarantees that it can never be invalid. */
  83                 valid = true;
  84                 goto end;
  85         }
  86
  87         valid = event_rule->validate(event_rule);
  88 end:
  89         return valid;
  90 }
  91
  92 LTTNG_HIDDEN
  93 int lttng_event_rule_serialize(const struct lttng_event_rule *event_rule,
  94                 struct lttng_payload *payload)
  95 {
  96         int ret;
  97         struct lttng_event_rule_comm event_rule_comm = {};
  98
  99         if (!event_rule) {
 100                 ret = -1;
 101                 goto end;
 102         }
 103
 104         event_rule_comm.event_rule_type = (int8_t) event_rule->type;
 105
 106         ret = lttng_dynamic_buffer_append(
 107                         &payload->buffer, &event_rule_comm, sizeof(event_rule_comm));
 108         if (ret) {
 109                 goto end;
 110         }
 111
 112         ret = event_rule->serialize(event_rule, payload);
 113         if (ret) {
 114                 goto end;
 115         }
 116 end:
 117         return ret;
 118 }
 119
 120 LTTNG_HIDDEN
 121 bool lttng_event_rule_is_equal(const struct lttng_event_rule *a,
 122                 const struct lttng_event_rule *b)
 123 {
 124         bool is_equal = false;
 125
 126         if (!a || !b) {
 127                 goto end;
 128         }
 129
 130         if (a->type != b->type) {
 131                 goto end;
 132         }
 133
 134         if (a == b) {
 135                 is_equal = true;
 136                 goto end;
 137         }
 138
 139         is_equal = a->equal ? a->equal(a, b) : true;
 140 end:
 141         return is_equal;
 142 }
 143
 144 LTTNG_HIDDEN
 145 ssize_t lttng_event_rule_create_from_payload(
 146                 struct lttng_payload_view *view,
 147                 struct lttng_event_rule **event_rule)
 148 {
 149         ssize_t ret, consumed = 0;
 150         event_rule_create_from_payload_cb create_from_payload = NULL;
 151         const struct lttng_event_rule_comm *event_rule_comm;
 152         const struct lttng_payload_view event_rule_comm_view =
 153                         lttng_payload_view_from_view(
 154                                         view, 0, sizeof(*event_rule_comm));
 155
 156         if (!view || !event_rule) {
 157                 ret = -1;
 158                 goto end;
 159         }
 160
 161         if (!lttng_payload_view_is_valid(&event_rule_comm_view)) {
 162                 ret = -1;
 163                 goto end;
 164         }
 165
 166         DBG("Deserializing event_rule from payload");
 167         event_rule_comm = (const struct lttng_event_rule_comm *) event_rule_comm_view.buffer.data;
 168         consumed += sizeof(*event_rule_comm);
 169
 170         switch ((enum lttng_event_rule_type) event_rule_comm->event_rule_type) {
 171         case LTTNG_EVENT_RULE_TYPE_TRACEPOINT:
 172                 create_from_payload =
 173                                 lttng_event_rule_tracepoint_create_from_payload;
 174                 break;
 175         case LTTNG_EVENT_RULE_TYPE_KPROBE:
 176                 create_from_payload = lttng_event_rule_kprobe_create_from_payload;
 177                 break;
 178         case LTTNG_EVENT_RULE_TYPE_KRETPROBE:
 179                 /* TODO */
 180                 break;
 181         case LTTNG_EVENT_RULE_TYPE_UPROBE:
 182                 create_from_payload = lttng_event_rule_uprobe_create_from_payload;
 183                 break;
 184         case LTTNG_EVENT_RULE_TYPE_SYSCALL:
 185                 create_from_payload =
 186                                 lttng_event_rule_syscall_create_from_payload;
 187                 break;
 188         default:
 189                 ERR("Attempted to create event rule of unknown type (%i)",
 190                                 (int) event_rule_comm->event_rule_type);
 191                 ret = -1;
 192                 goto end;
 193         }
 194
 195         assert(create_from_payload);
 196
 197         {
 198                 struct lttng_payload_view child_view =
 199                                 lttng_payload_view_from_view(
 200                                                 view, consumed, -1);
 201
 202                 ret = create_from_payload(&child_view, event_rule);
 203                 if (ret < 0) {
 204                         goto end;
 205                 }
 206
 207                 consumed += ret;
 208         }
 209
 210         if (!lttng_event_rule_validate(*event_rule)) {
 211                 ret = -1;
 212                 goto end;
 213         }
 214
 215         ret = consumed;
 216 end:
 217         return ret;
 218 }
 219
 220 LTTNG_HIDDEN
 221 void lttng_event_rule_init(struct lttng_event_rule *event_rule,
 222                 enum lttng_event_rule_type type)
 223 {
 224         urcu_ref_init(&event_rule->ref);
 225         event_rule->type = type;
 226 }
 227
 228 LTTNG_HIDDEN
 229 bool lttng_event_rule_get(struct lttng_event_rule *event_rule)
 230 {
 231         return urcu_ref_get_unless_zero(&event_rule->ref);
 232 }
 233
 234 LTTNG_HIDDEN
 235 void lttng_event_rule_put(struct lttng_event_rule *event_rule)
 236 {
 237         if (!event_rule) {
 238                 return;
 239         }
 240
 241         assert(event_rule->ref.refcount);
 242         urcu_ref_put(&event_rule->ref, lttng_event_rule_release);
 243 }
 244
 245 LTTNG_HIDDEN
 246 enum lttng_error_code lttng_event_rule_generate_filter_bytecode(
 247                 struct lttng_event_rule *rule,
 248                 const struct lttng_credentials *creds)
 249 {
 250         assert(rule->generate_filter_bytecode);
 251         return rule->generate_filter_bytecode(rule, creds);
 252 }
 253
 254 LTTNG_HIDDEN
 255 const char *lttng_event_rule_get_filter(const struct lttng_event_rule *rule)
 256 {
 257         assert(rule->get_filter);
 258         return rule->get_filter(rule);
 259 }
 260
 261 LTTNG_HIDDEN
 262 const struct lttng_filter_bytecode *lttng_event_rule_get_filter_bytecode(
 263                 const struct lttng_event_rule *rule)
 264 {
 265         assert(rule->get_filter_bytecode);
 266         return rule->get_filter_bytecode(rule);
 267 }
 268
 269 LTTNG_HIDDEN
 270 struct lttng_event_exclusion *lttng_event_rule_generate_exclusions(
 271                 const struct lttng_event_rule *rule)
 272 {
 273         assert(rule->generate_exclusions);
 274         return rule->generate_exclusions(rule);
 275 }
 276
 277 LTTNG_HIDDEN
 278 const char *lttng_event_rule_type_str(enum lttng_event_rule_type type)
 279 {
 280         switch (type) {
 281         case LTTNG_EVENT_RULE_TYPE_UNKNOWN:
 282                 return "unknown";
 283         case LTTNG_EVENT_RULE_TYPE_TRACEPOINT:
 284                 return "tracepoint";
 285         case LTTNG_EVENT_RULE_TYPE_SYSCALL:
 286                 return "syscall";
 287         case LTTNG_EVENT_RULE_TYPE_KPROBE:
 288                 return "probe";
 289         case LTTNG_EVENT_RULE_TYPE_KRETPROBE:
 290                 return "function";
 291         case LTTNG_EVENT_RULE_TYPE_UPROBE:
 292                 return "userspace-probe";
 293         default:
 294                 abort();
 295         }
 296 }
 297
 298 LTTNG_HIDDEN
 299 unsigned long lttng_event_rule_hash(const struct lttng_event_rule *rule)
 300 {
 301         assert(rule->hash);
 302         return rule->hash(rule);
 303 }