01d5c463be
The error check was added for `FileAccessUnix` but it's not an error when both `p_src` and `p_length` are zero. Added correct error checks to all implementations to prevent the actual erroneous case: `p_src` is nullptr but `p_length > 0` (risk of null pointer indexing). Fixes #33564.
319 lines
8.6 KiB
C++
319 lines
8.6 KiB
C++
/*************************************************************************/
|
|
/* file_access_encrypted.cpp */
|
|
/*************************************************************************/
|
|
/* This file is part of: */
|
|
/* GODOT ENGINE */
|
|
/* https://godotengine.org */
|
|
/*************************************************************************/
|
|
/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur. */
|
|
/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md). */
|
|
/* */
|
|
/* Permission is hereby granted, free of charge, to any person obtaining */
|
|
/* a copy of this software and associated documentation files (the */
|
|
/* "Software"), to deal in the Software without restriction, including */
|
|
/* without limitation the rights to use, copy, modify, merge, publish, */
|
|
/* distribute, sublicense, and/or sell copies of the Software, and to */
|
|
/* permit persons to whom the Software is furnished to do so, subject to */
|
|
/* the following conditions: */
|
|
/* */
|
|
/* The above copyright notice and this permission notice shall be */
|
|
/* included in all copies or substantial portions of the Software. */
|
|
/* */
|
|
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
|
|
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
|
|
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
|
|
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
|
|
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
|
|
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
|
|
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
|
|
/*************************************************************************/
|
|
|
|
#include "file_access_encrypted.h"
|
|
|
|
#include "core/crypto/crypto_core.h"
|
|
#include "core/string/print_string.h"
|
|
#include "core/variant/variant.h"
|
|
|
|
#include <stdio.h>
|
|
|
|
Error FileAccessEncrypted::open_and_parse(FileAccess *p_base, const Vector<uint8_t> &p_key, Mode p_mode, bool p_with_magic) {
|
|
ERR_FAIL_COND_V_MSG(file != nullptr, ERR_ALREADY_IN_USE, "Can't open file while another file from path '" + file->get_path_absolute() + "' is open.");
|
|
ERR_FAIL_COND_V(p_key.size() != 32, ERR_INVALID_PARAMETER);
|
|
|
|
pos = 0;
|
|
eofed = false;
|
|
use_magic = p_with_magic;
|
|
|
|
if (p_mode == MODE_WRITE_AES256) {
|
|
data.clear();
|
|
writing = true;
|
|
file = p_base;
|
|
key = p_key;
|
|
|
|
} else if (p_mode == MODE_READ) {
|
|
writing = false;
|
|
key = p_key;
|
|
|
|
if (use_magic) {
|
|
uint32_t magic = p_base->get_32();
|
|
ERR_FAIL_COND_V(magic != ENCRYPTED_HEADER_MAGIC, ERR_FILE_UNRECOGNIZED);
|
|
}
|
|
|
|
unsigned char md5d[16];
|
|
p_base->get_buffer(md5d, 16);
|
|
length = p_base->get_64();
|
|
|
|
unsigned char iv[16];
|
|
for (int i = 0; i < 16; i++) {
|
|
iv[i] = p_base->get_8();
|
|
}
|
|
|
|
base = p_base->get_position();
|
|
ERR_FAIL_COND_V(p_base->get_length() < base + length, ERR_FILE_CORRUPT);
|
|
uint64_t ds = length;
|
|
if (ds % 16) {
|
|
ds += 16 - (ds % 16);
|
|
}
|
|
data.resize(ds);
|
|
|
|
uint64_t blen = p_base->get_buffer(data.ptrw(), ds);
|
|
ERR_FAIL_COND_V(blen != ds, ERR_FILE_CORRUPT);
|
|
|
|
{
|
|
CryptoCore::AESContext ctx;
|
|
|
|
ctx.set_encode_key(key.ptrw(), 256); // Due to the nature of CFB, same key schedule is used for both encryption and decryption!
|
|
ctx.decrypt_cfb(ds, iv, data.ptrw(), data.ptrw());
|
|
}
|
|
|
|
data.resize(length);
|
|
|
|
unsigned char hash[16];
|
|
ERR_FAIL_COND_V(CryptoCore::md5(data.ptr(), data.size(), hash) != OK, ERR_BUG);
|
|
|
|
ERR_FAIL_COND_V_MSG(String::md5(hash) != String::md5(md5d), ERR_FILE_CORRUPT, "The MD5 sum of the decrypted file does not match the expected value. It could be that the file is corrupt, or that the provided decryption key is invalid.");
|
|
|
|
file = p_base;
|
|
}
|
|
|
|
return OK;
|
|
}
|
|
|
|
Error FileAccessEncrypted::open_and_parse_password(FileAccess *p_base, const String &p_key, Mode p_mode) {
|
|
String cs = p_key.md5_text();
|
|
ERR_FAIL_COND_V(cs.length() != 32, ERR_INVALID_PARAMETER);
|
|
Vector<uint8_t> key;
|
|
key.resize(32);
|
|
for (int i = 0; i < 32; i++) {
|
|
key.write[i] = cs[i];
|
|
}
|
|
|
|
return open_and_parse(p_base, key, p_mode);
|
|
}
|
|
|
|
Error FileAccessEncrypted::_open(const String &p_path, int p_mode_flags) {
|
|
return OK;
|
|
}
|
|
|
|
void FileAccessEncrypted::close() {
|
|
if (!file) {
|
|
return;
|
|
}
|
|
|
|
_release();
|
|
|
|
file->close();
|
|
memdelete(file);
|
|
|
|
file = nullptr;
|
|
}
|
|
|
|
void FileAccessEncrypted::release() {
|
|
if (!file) {
|
|
return;
|
|
}
|
|
|
|
_release();
|
|
|
|
file = nullptr;
|
|
}
|
|
|
|
void FileAccessEncrypted::_release() {
|
|
if (writing) {
|
|
Vector<uint8_t> compressed;
|
|
uint64_t len = data.size();
|
|
if (len % 16) {
|
|
len += 16 - (len % 16);
|
|
}
|
|
|
|
unsigned char hash[16];
|
|
ERR_FAIL_COND(CryptoCore::md5(data.ptr(), data.size(), hash) != OK); // Bug?
|
|
|
|
compressed.resize(len);
|
|
memset(compressed.ptrw(), 0, len);
|
|
for (int i = 0; i < data.size(); i++) {
|
|
compressed.write[i] = data[i];
|
|
}
|
|
|
|
CryptoCore::AESContext ctx;
|
|
ctx.set_encode_key(key.ptrw(), 256);
|
|
|
|
if (use_magic) {
|
|
file->store_32(ENCRYPTED_HEADER_MAGIC);
|
|
}
|
|
|
|
file->store_buffer(hash, 16);
|
|
file->store_64(data.size());
|
|
|
|
unsigned char iv[16];
|
|
for (int i = 0; i < 16; i++) {
|
|
iv[i] = Math::rand() % 256;
|
|
file->store_8(iv[i]);
|
|
}
|
|
|
|
ctx.encrypt_cfb(len, iv, compressed.ptrw(), compressed.ptrw());
|
|
|
|
file->store_buffer(compressed.ptr(), compressed.size());
|
|
data.clear();
|
|
}
|
|
}
|
|
|
|
bool FileAccessEncrypted::is_open() const {
|
|
return file != nullptr;
|
|
}
|
|
|
|
String FileAccessEncrypted::get_path() const {
|
|
if (file) {
|
|
return file->get_path();
|
|
} else {
|
|
return "";
|
|
}
|
|
}
|
|
|
|
String FileAccessEncrypted::get_path_absolute() const {
|
|
if (file) {
|
|
return file->get_path_absolute();
|
|
} else {
|
|
return "";
|
|
}
|
|
}
|
|
|
|
void FileAccessEncrypted::seek(uint64_t p_position) {
|
|
if (p_position > get_length()) {
|
|
p_position = get_length();
|
|
}
|
|
|
|
pos = p_position;
|
|
eofed = false;
|
|
}
|
|
|
|
void FileAccessEncrypted::seek_end(int64_t p_position) {
|
|
seek(get_length() + p_position);
|
|
}
|
|
|
|
uint64_t FileAccessEncrypted::get_position() const {
|
|
return pos;
|
|
}
|
|
|
|
uint64_t FileAccessEncrypted::get_length() const {
|
|
return data.size();
|
|
}
|
|
|
|
bool FileAccessEncrypted::eof_reached() const {
|
|
return eofed;
|
|
}
|
|
|
|
uint8_t FileAccessEncrypted::get_8() const {
|
|
ERR_FAIL_COND_V_MSG(writing, 0, "File has not been opened in read mode.");
|
|
if (pos >= get_length()) {
|
|
eofed = true;
|
|
return 0;
|
|
}
|
|
|
|
uint8_t b = data[pos];
|
|
pos++;
|
|
return b;
|
|
}
|
|
|
|
uint64_t FileAccessEncrypted::get_buffer(uint8_t *p_dst, uint64_t p_length) const {
|
|
ERR_FAIL_COND_V(!p_dst && p_length > 0, -1);
|
|
ERR_FAIL_COND_V_MSG(writing, -1, "File has not been opened in read mode.");
|
|
|
|
uint64_t to_copy = MIN(p_length, get_length() - pos);
|
|
for (uint64_t i = 0; i < to_copy; i++) {
|
|
p_dst[i] = data[pos++];
|
|
}
|
|
|
|
if (to_copy < p_length) {
|
|
eofed = true;
|
|
}
|
|
|
|
return to_copy;
|
|
}
|
|
|
|
Error FileAccessEncrypted::get_error() const {
|
|
return eofed ? ERR_FILE_EOF : OK;
|
|
}
|
|
|
|
void FileAccessEncrypted::store_buffer(const uint8_t *p_src, uint64_t p_length) {
|
|
ERR_FAIL_COND_MSG(!writing, "File has not been opened in write mode.");
|
|
ERR_FAIL_COND(!p_src && p_length > 0);
|
|
|
|
if (pos < get_length()) {
|
|
for (uint64_t i = 0; i < p_length; i++) {
|
|
store_8(p_src[i]);
|
|
}
|
|
} else if (pos == get_length()) {
|
|
data.resize(pos + p_length);
|
|
for (uint64_t i = 0; i < p_length; i++) {
|
|
data.write[pos + i] = p_src[i];
|
|
}
|
|
pos += p_length;
|
|
}
|
|
}
|
|
|
|
void FileAccessEncrypted::flush() {
|
|
ERR_FAIL_COND_MSG(!writing, "File has not been opened in write mode.");
|
|
|
|
// encrypted files keep data in memory till close()
|
|
}
|
|
|
|
void FileAccessEncrypted::store_8(uint8_t p_dest) {
|
|
ERR_FAIL_COND_MSG(!writing, "File has not been opened in write mode.");
|
|
|
|
if (pos < get_length()) {
|
|
data.write[pos] = p_dest;
|
|
pos++;
|
|
} else if (pos == get_length()) {
|
|
data.push_back(p_dest);
|
|
pos++;
|
|
}
|
|
}
|
|
|
|
bool FileAccessEncrypted::file_exists(const String &p_name) {
|
|
FileAccess *fa = FileAccess::open(p_name, FileAccess::READ);
|
|
if (!fa) {
|
|
return false;
|
|
}
|
|
memdelete(fa);
|
|
return true;
|
|
}
|
|
|
|
uint64_t FileAccessEncrypted::_get_modified_time(const String &p_file) {
|
|
return 0;
|
|
}
|
|
|
|
uint32_t FileAccessEncrypted::_get_unix_permissions(const String &p_file) {
|
|
return 0;
|
|
}
|
|
|
|
Error FileAccessEncrypted::_set_unix_permissions(const String &p_file, uint32_t p_permissions) {
|
|
ERR_PRINT("Setting UNIX permissions on encrypted files is not implemented yet.");
|
|
return ERR_UNAVAILABLE;
|
|
}
|
|
|
|
FileAccessEncrypted::~FileAccessEncrypted() {
|
|
if (file) {
|
|
close();
|
|
}
|
|
}
|