1/*
2 * Copyright (C) 2018 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include "src/perfetto_cmd/rate_limiter.h"
18
19#include <sys/stat.h>
20#include <sys/types.h>
21#include <unistd.h>
22
23#include "perfetto/base/logging.h"
24#include "perfetto/base/scoped_file.h"
25#include "perfetto/base/utils.h"
26#include "src/perfetto_cmd/perfetto_cmd.h"
27
28namespace perfetto {
29namespace {
30
31// 5 mins between traces.
32const uint64_t kCooldownInSeconds = 60 * 5;
33
34// Every 24 hours we reset how much we've uploaded.
35const uint64_t kMaxUploadResetPeriodInSeconds = 60 * 60 * 24;
36
37// Maximum of 10mb every 24h.
38const uint64_t kMaxUploadInBytes = 1024 * 1024 * 10;
39
40}  // namespace
41
42RateLimiter::RateLimiter() = default;
43RateLimiter::~RateLimiter() = default;
44
45bool RateLimiter::ShouldTrace(const Args& args) {
46  uint64_t now_in_s = static_cast<uint64_t>(args.current_time.count());
47
48  // Not uploading?
49  // -> We can just trace.
50  if (!args.is_dropbox)
51    return true;
52
53  // The state file is gone.
54  // Maybe we're tracing for the first time or maybe something went wrong the
55  // last time we tried to save the state. Either way reinitialize the state
56  // file.
57  if (!StateFileExists()) {
58    // We can't write the empty state file?
59    // -> Give up.
60    if (!ClearState()) {
61      PERFETTO_ELOG("Guardrail: failed to initialize guardrail state.");
62      return false;
63    }
64  }
65
66  bool loaded_state = LoadState(&state_);
67
68  // Failed to load the state?
69  // Current time is before either saved times?
70  // Last saved trace time is before first saved trace time?
71  // -> Try to save a clean state but don't trace.
72  if (!loaded_state || now_in_s < state_.first_trace_timestamp() ||
73      now_in_s < state_.last_trace_timestamp() ||
74      state_.last_trace_timestamp() < state_.first_trace_timestamp()) {
75    ClearState();
76    PERFETTO_ELOG("Guardrail: state invalid, clearing it.");
77    if (!args.ignore_guardrails)
78      return false;
79  }
80
81  // If we've uploaded in the last 5mins we shouldn't trace now.
82  if ((now_in_s - state_.last_trace_timestamp()) < kCooldownInSeconds) {
83    PERFETTO_ELOG("Guardrail: Uploaded to DropBox in the last 5mins.");
84    if (!args.ignore_guardrails)
85      return false;
86  }
87
88  // First trace was more than 24h ago? Reset state.
89  if ((now_in_s - state_.first_trace_timestamp()) >
90      kMaxUploadResetPeriodInSeconds) {
91    state_.set_first_trace_timestamp(0);
92    state_.set_last_trace_timestamp(0);
93    state_.set_total_bytes_uploaded(0);
94    return true;
95  }
96
97  // If we've uploaded more than 10mb in the last 24 hours we shouldn't trace
98  // now.
99  uint64_t max_upload_guardrail = args.max_upload_bytes_override > 0
100                                      ? args.max_upload_bytes_override
101                                      : kMaxUploadInBytes;
102  if (state_.total_bytes_uploaded() > max_upload_guardrail) {
103    PERFETTO_ELOG("Guardrail: Uploaded >10mb DropBox in the last 24h.");
104    if (!args.ignore_guardrails)
105      return false;
106  }
107
108  return true;
109}
110
111bool RateLimiter::OnTraceDone(const Args& args, bool success, size_t bytes) {
112  uint64_t now_in_s = static_cast<uint64_t>(args.current_time.count());
113
114  // Failed to upload? Don't update the state.
115  if (!success)
116    return false;
117
118  if (!args.is_dropbox)
119    return true;
120
121  // If the first trace timestamp is 0 (either because this is the
122  // first time or because it was reset for being more than 24h ago).
123  // -> We update it to the time of this trace.
124  if (state_.first_trace_timestamp() == 0)
125    state_.set_first_trace_timestamp(now_in_s);
126  // Always updated the last trace timestamp.
127  state_.set_last_trace_timestamp(now_in_s);
128  // Add the amount we uploaded to the running total.
129  state_.set_total_bytes_uploaded(state_.total_bytes_uploaded() + bytes);
130
131  if (!SaveState(state_)) {
132    PERFETTO_ELOG("Failed to save state.");
133    return false;
134  }
135
136  return true;
137}
138
139std::string RateLimiter::GetStateFilePath() const {
140  return std::string(kTempDropBoxTraceDir) + "/.guardraildata";
141}
142
143bool RateLimiter::StateFileExists() {
144  struct stat out;
145  return stat(GetStateFilePath().c_str(), &out) != -1;
146}
147
148bool RateLimiter::ClearState() {
149  PerfettoCmdState zero{};
150  zero.set_total_bytes_uploaded(0);
151  zero.set_last_trace_timestamp(0);
152  zero.set_first_trace_timestamp(0);
153  bool success = SaveState(zero);
154  if (!success && StateFileExists())
155    remove(GetStateFilePath().c_str());
156  return success;
157}
158
159bool RateLimiter::LoadState(PerfettoCmdState* state) {
160  base::ScopedFile in_fd;
161  in_fd.reset(open(GetStateFilePath().c_str(), O_RDONLY));
162
163  if (!in_fd)
164    return false;
165  char buf[1024];
166  ssize_t bytes = PERFETTO_EINTR(read(in_fd.get(), &buf, sizeof(buf)));
167  if (bytes <= 0)
168    return false;
169  return state->ParseFromArray(&buf, static_cast<int>(bytes));
170}
171
172bool RateLimiter::SaveState(const PerfettoCmdState& state) {
173  base::ScopedFile out_fd;
174  out_fd.reset(
175      open(GetStateFilePath().c_str(), O_WRONLY | O_CREAT | O_TRUNC, 0600));
176  if (!out_fd)
177    return false;
178  char buf[1024];
179  size_t size = static_cast<size_t>(state.ByteSize());
180  PERFETTO_CHECK(size < sizeof(buf));
181  if (!state.SerializeToArray(&buf, static_cast<int>(size)))
182    return false;
183  ssize_t written = PERFETTO_EINTR(write(out_fd.get(), &buf, size));
184  return written >= 0 && static_cast<size_t>(written) == size;
185}
186
187}  // namespace perfetto
188