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/*
* Copyright (C) 2014 The Android Open Source Project
*
* 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.
*/
#ifndef LIBZIPARCHIVE_ENTRY_NAME_UTILS_INL_H_
#define LIBZIPARCHIVE_ENTRY_NAME_UTILS_INL_H_
#include <stddef.h>
#include <stdint.h>
#include <limits>
// Check if |length| bytes at |entry_name| constitute a valid entry name.
// Entry names must be valid UTF-8 and must not contain '0'. They also must
// fit into the central directory record.
inline bool IsValidEntryName(const uint8_t* entry_name, const size_t length) {
if (length > std::numeric_limits<uint16_t>::max()) {
return false;
}
for (size_t i = 0; i < length; ++i) {
const uint8_t byte = entry_name[i];
if (byte == 0) {
return false;
} else if ((byte & 0x80) == 0) {
// Single byte sequence.
continue;
} else if ((byte & 0xc0) == 0x80 || (byte & 0xfe) == 0xfe) {
// Invalid sequence.
return false;
} else {
// 2-5 byte sequences.
for (uint8_t first = static_cast<uint8_t>((byte & 0x7f) << 1); first & 0x80;
first = static_cast<uint8_t>((first & 0x7f) << 1)) {
++i;
// Missing continuation byte..
if (i == length) {
return false;
}
// Invalid continuation byte.
const uint8_t continuation_byte = entry_name[i];
if ((continuation_byte & 0xc0) != 0x80) {
return false;
}
}
}
}
return true;
}
#endif // LIBZIPARCHIVE_ENTRY_NAME_UTILS_INL_H_