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