File: boarding_pass_extractor.cc

package info (click to toggle)
chromium 139.0.7258.127-1
  • links: PTS, VCS
  • area: main
  • in suites:
  • size: 6,122,068 kB
  • sloc: cpp: 35,100,771; ansic: 7,163,530; javascript: 4,103,002; python: 1,436,920; asm: 946,517; xml: 746,709; pascal: 187,653; perl: 88,691; sh: 88,436; objc: 79,953; sql: 51,488; cs: 44,583; fortran: 24,137; makefile: 22,147; tcl: 15,277; php: 13,980; yacc: 8,984; ruby: 7,485; awk: 3,720; lisp: 3,096; lex: 1,327; ada: 727; jsp: 228; sed: 36
file content (185 lines) | stat: -rw-r--r-- 6,376 bytes parent folder | download | duplicates (9)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
// Copyright 2023 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifdef UNSAFE_BUFFERS_BUILD
// TODO(crbug.com/40285824): Remove this and convert code to safer constructs.
#pragma allow_unsafe_buffers
#endif

#include "chrome/renderer/wallet/boarding_pass_extractor.h"

#include "base/metrics/histogram_macros.h"
#include "chrome/common/chrome_isolated_world_ids.h"
#include "content/public/renderer/render_frame.h"
#include "content/public/renderer/render_thread.h"
#include "services/metrics/public/cpp/ukm_builders.h"
#include "third_party/blink/public/platform/browser_interface_broker_proxy.h"
#include "third_party/blink/public/platform/scheduler/web_agent_group_scheduler.h"
#include "third_party/blink/public/platform/web_string.h"
#include "third_party/blink/public/web/web_local_frame.h"
#include "third_party/blink/public/web/web_script_source.h"
#include "v8/include/v8-isolate.h"

namespace wallet {

namespace {
const std::string GetDefaultExtractionScript() {
  std::string script = R"###(
    // Check if the str contains 'boarding pass'.
    function containBoardingPass(str) {
        return str.toLowerCase().replace(/\s+/g, '').includes('boardingpass');
    }

    // Scale up the base64 encoded image to be detectable by BarcodeDetector.
    function scaleUpIfNeeded(img) {
        if (img.src.startsWith('data:image/')
            && (img.width < 500 || image.height < 500)) {
            let canvas = new OffscreenCanvas(500, 500);
            let ctx = canvas.getContext('2d');
            ctx.ImageSmoothingEnabled = false;
            ctx.drawImage(img, 0, 0, 500, 500);
            return canvas;
        }
        return img;
    }

    // Check if the rawValue is a valid BCBP string.
    function isValidBoardingPass(rawValue) {
        return rawValue.length > 60 && /^M[1-9]/.test(rawValue);
    }

    // Detect and decode boarding passes on current web page.
    async function detectBoardingPass() {
        var results = [];
        // Check if BarcodeDetector is supported by current browser.
        if (!'BarcodeDetector' in window) {
            return [];
        }

        // Check if current URL or page title contains 'boarding pass'.
        if (!containBoardingPass(window.location.href)
            && !containBoardingPass(document.title)) {
            return [];
        }

        var detector;
        try {
            detector = new BarcodeDetector();
        } catch (error) {
            return [];
        }
        for (let i = 0; i < document.images.length; ++i) {
            try {
                const barcodes = await detector.detect(
                    scaleUpIfNeeded(document.images[i]));
                for (const barcode of barcodes) {
                    // Check if it's a valid boarding pass
                    if (barcode.rawValue
                        && isValidBoardingPass(barcode.rawValue)) {
                        results.push(barcode.rawValue);
                    }
                }
            } catch (error) {
            }
        }
        return results;
    }

    detected_results_promise = detectBoardingPass();
  )###";
  return script;
}

std::vector<std::string> ConvertResultsToStrings(base::Value& value) {
  std::vector<std::string> results;

  if (!value.is_list()) {
    return results;
  }

  for (const auto& item : value.GetList()) {
    if (!item.is_string()) {
      continue;
    }
    results.push_back(item.GetString());
  }
  return results;
}
}  // namespace

BoardingPassExtractor::BoardingPassExtractor(
    content::RenderFrame* render_frame,
    service_manager::BinderRegistry* registry)
    : content::RenderFrameObserver(render_frame) {
  // Being a RenderFrameObserver, this object is scoped to the RenderFrame.
  // Unretained is safe here because `registry` is also scoped to the
  // RenderFrame.
  registry->AddInterface(base::BindRepeating(
      &BoardingPassExtractor::BindReceiver, base::Unretained(this)));

  mojo::Remote<ukm::mojom::UkmRecorderFactory> factory;
  content::RenderThread::Get()->BindHostReceiver(
      factory.BindNewPipeAndPassReceiver());
  ukm_recorder_ = ukm::MojoUkmRecorder::Create(*factory);
}

BoardingPassExtractor::~BoardingPassExtractor() = default;

void BoardingPassExtractor::BindReceiver(
    mojo::PendingReceiver<mojom::BoardingPassExtractor> receiver) {
  receiver_.reset();
  receiver_.Bind(std::move(receiver));
}

void BoardingPassExtractor::OnDestruct() {
  delete this;
}

void BoardingPassExtractor::ExtractBoardingPass(
    ExtractBoardingPassCallback callback) {
  ExtractBoardingPassWithScript(GetDefaultExtractionScript(),
                                std::move(callback));
}

void BoardingPassExtractor::ExtractBoardingPassWithScript(
    const std::string& script,
    ExtractBoardingPassCallback callback) {
  blink::WebLocalFrame* main_frame = render_frame()->GetWebFrame();
  v8::HandleScope handle_scope(main_frame->GetAgentGroupScheduler()->Isolate());
  blink::WebScriptSource source =
      blink::WebScriptSource(blink::WebString::FromUTF8(script));

  main_frame->RequestExecuteScript(
      ISOLATED_WORLD_ID_CHROME_INTERNAL, base::span_from_ref(source),
      blink::mojom::UserActivationOption::kDoNotActivate,
      blink::mojom::EvaluationTiming::kAsynchronous,
      blink::mojom::LoadEventBlockingOption::kDoNotBlock,
      base::BindOnce(&BoardingPassExtractor::OnBoardingPassExtracted,
                     base::Unretained(this), std::move(callback)),
      blink::BackForwardCacheAware::kAllow,
      blink::mojom::WantResultOption::kWantResult,
      blink::mojom::PromiseResultOption::kAwait);
}

void BoardingPassExtractor::OnBoardingPassExtracted(
    ExtractBoardingPassCallback callback,
    std::optional<base::Value> results,
    base::TimeTicks start_time) {
  std::vector<std::string> boarding_passes;
  if (results.has_value()) {
    boarding_passes = ConvertResultsToStrings(*results);
  }

  ukm::builders::Wallet_BoardingPassDetect(
      render_frame()->GetWebFrame()->GetDocument().GetUkmSourceId())
      .SetDetected(!boarding_passes.empty())
      .Record(ukm_recorder_.get());

  UMA_HISTOGRAM_BOOLEAN("Android.Wallet.BoardingPass.Detected",
                        !boarding_passes.empty());

  std::move(callback).Run(std::move(boarding_passes));
}

}  // namespace wallet