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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
commit36d22d82aa202bb199967e9512281e9a53db42c9 (patch)
tree105e8c98ddea1c1e4784a60a5a6410fa416be2de /media/gmp-clearkey/0.1/ClearKeyBase64.cpp
parentInitial commit. (diff)
downloadfirefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.tar.xz
firefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.zip
Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'media/gmp-clearkey/0.1/ClearKeyBase64.cpp')
-rw-r--r--media/gmp-clearkey/0.1/ClearKeyBase64.cpp90
1 files changed, 90 insertions, 0 deletions
diff --git a/media/gmp-clearkey/0.1/ClearKeyBase64.cpp b/media/gmp-clearkey/0.1/ClearKeyBase64.cpp
new file mode 100644
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+++ b/media/gmp-clearkey/0.1/ClearKeyBase64.cpp
@@ -0,0 +1,90 @@
+/*
+ * Copyright 2015, Mozilla Foundation and contributors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "ClearKeyBase64.h"
+
+#include <algorithm>
+
+using std::string;
+using std::vector;
+
+/**
+ * Take a base64-encoded string, convert (in-place) each character to its
+ * corresponding value in the [0x00, 0x3f] range, and truncate any padding.
+ */
+static bool Decode6Bit(string& aStr) {
+ for (size_t i = 0; i < aStr.length(); i++) {
+ if (aStr[i] >= 'A' && aStr[i] <= 'Z') {
+ aStr[i] -= 'A';
+ } else if (aStr[i] >= 'a' && aStr[i] <= 'z') {
+ aStr[i] -= 'a' - 26;
+ } else if (aStr[i] >= '0' && aStr[i] <= '9') {
+ aStr[i] -= '0' - 52;
+ } else if (aStr[i] == '-' || aStr[i] == '+') {
+ aStr[i] = 62;
+ } else if (aStr[i] == '_' || aStr[i] == '/') {
+ aStr[i] = 63;
+ } else {
+ // Truncate '=' padding at the end of the aString.
+ if (aStr[i] != '=') {
+ aStr.erase(i, string::npos);
+ return false;
+ }
+ aStr[i] = '\0';
+ aStr.resize(i);
+ break;
+ }
+ }
+
+ return true;
+}
+
+bool DecodeBase64(const string& aEncoded, vector<uint8_t>& aOutDecoded) {
+ if (aEncoded.empty()) {
+ aOutDecoded.clear();
+ return true;
+ }
+ if (aEncoded.size() == 1) {
+ // Invalid Base64 encoding.
+ return false;
+ }
+ string encoded = aEncoded;
+ if (!Decode6Bit(encoded)) {
+ return false;
+ }
+
+ // The number of bytes we haven't yet filled in the current byte, mod 8.
+ int shift = 0;
+
+ aOutDecoded.resize((encoded.size() * 3) / 4);
+ vector<uint8_t>::iterator out = aOutDecoded.begin();
+ for (size_t i = 0; i < encoded.length(); i++) {
+ if (!shift) {
+ *out = encoded[i] << 2;
+ } else {
+ *out |= encoded[i] >> (6 - shift);
+ out++;
+ if (out == aOutDecoded.end()) {
+ // Hit last 6bit octed in encoded, which is padding and can be ignored.
+ break;
+ }
+ *out = encoded[i] << (shift + 2);
+ }
+ shift = (shift + 2) % 8;
+ }
+
+ return true;
+}