Download web payment manifests.

components/payments/content/android/utility/fingerprint_parser.cc

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "components/payments/content/android/utility/fingerprint_parser.h"
+
+#include "base/logging.h"
+#include "base/numerics/safe_conversions.h"
+
+namespace payments {
+namespace {
+
+bool IsUpperCaseHexDigit(char c) {
+  return (c >= '0' && c <= '9') || (c >= 'A' && c <= 'F');
+}
+
+uint8_t HexDigitToByte(char c) {
+  DCHECK(IsUpperCaseHexDigit(c));
+  return base::checked_cast<uint8_t>(c >= '0' && c <= '9' ? c - '0'
+                                                          : c - 'A' + 10);
+}
+
+}  // namespace
+
+std::vector<uint8_t> FingerprintStringToByteArray(const std::string& input) {
+  std::vector<uint8_t> output;
+  if (input.size() != 32 * 3 - 1)
+    return output;
+
+  for (size_t i = 0; i < input.size(); i += 3) {
+    if (i < input.size() - 2 && input[i + 2] != ':') {
+      output.clear();
+      return output;
+    }
+
+    char big_end = input[i];
+    char little_end = input[i + 1];
+    if (!IsUpperCaseHexDigit(big_end) || !IsUpperCaseHexDigit(little_end)) {
+      output.clear();
+      return output;
+    }
+
+    output.push_back(HexDigitToByte(big_end) * static_cast<uint8_t>(16) +
+                     HexDigitToByte(little_end));
+  }
+
+  return output;
+}
+
+}  // namespace payments