gecko-dev/netwerk/dns/IDNBlocklistUtils.cpp

87 lines
2.7 KiB
C++

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "IDNBlocklistUtils.h"
#include "mozilla/Preferences.h"
#include "nsStringFwd.h"
namespace mozilla {
namespace net {
static constexpr char16_t sBlocklistPairs[][2] = {
#include "IDNCharacterBlocklist.inc"
};
void RemoveCharFromBlocklist(char16_t aChar,
nsTArray<BlocklistRange>& aBlocklist) {
auto pos = aBlocklist.BinaryIndexOf(aChar, BlocklistPairToCharComparator());
if (pos == nsTArray<BlocklistRange>::NoIndex) {
return;
}
auto& pair = aBlocklist[pos];
// If the matched range has a length of one, we can just remove it
if (pair.second == pair.first) {
aBlocklist.RemoveElementAt(pos);
return;
}
// If the character matches the first element in the range, just update
// the range.
if (aChar == pair.first) {
pair.first = pair.first + 1;
return;
}
// Also if it matches the last character in the range, we just update it.
if (aChar == pair.second) {
pair.second = pair.second - 1;
return;
}
// Our character is in the middle of the range, splitting it in two.
// We update the matched range to reflect the values before the character,
// and insert a new range that represents the values after.
char16_t lastElement = pair.second;
pair.second = aChar - 1;
aBlocklist.InsertElementAt(pos + 1,
std::make_pair(char16_t(aChar + 1), lastElement));
}
void InitializeBlocklist(nsTArray<BlocklistRange>& aBlocklist) {
aBlocklist.Clear();
for (auto const& arr : sBlocklistPairs) {
// The hardcoded pairs are already sorted.
aBlocklist.AppendElement(std::make_pair(arr[0], arr[1]));
}
nsAutoString extraAllowed;
nsresult rv =
Preferences::GetString("network.IDN.extra_allowed_chars", extraAllowed);
if (NS_SUCCEEDED(rv) && !extraAllowed.IsEmpty()) {
const char16_t* cur = extraAllowed.BeginReading();
const char16_t* end = extraAllowed.EndReading();
// Characters in the allowed list are removed from the blocklist.
for (; cur < end; ++cur) {
RemoveCharFromBlocklist(*cur, aBlocklist);
}
}
nsAutoString extraBlocked;
rv = Preferences::GetString("network.IDN.extra_blocked_chars", extraBlocked);
// We add each extra blocked character to the blocklist as a separate range.
if (NS_SUCCEEDED(rv) && !extraBlocked.IsEmpty()) {
for (size_t i = 0; i < extraBlocked.Length(); ++i) {
aBlocklist.AppendElement(
std::make_pair(extraBlocked[i], extraBlocked[i]));
}
aBlocklist.Sort(BlocklistEntryComparator());
}
}
} // namespace net
} // namespace mozilla