mirror of
https://github.com/tfussell/xlnt.git
synced 2024-03-22 13:11:17 +08:00
797 lines
33 KiB
C++
797 lines
33 KiB
C++
// Copyright (c) 2014-2017 Thomas Fussell
|
|
//
|
|
// 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, WRISING FROM,
|
|
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
|
// THE SOFTWARE
|
|
//
|
|
// @license: http://www.opensource.org/licenses/mit-license.php
|
|
// @author: see AUTHORS file
|
|
|
|
#include <array>
|
|
|
|
#include <xlnt/utils/exceptions.hpp>
|
|
#include <xlnt/workbook/workbook.hpp>
|
|
#include <detail/constants.hpp>
|
|
#include <detail/include_cryptopp.hpp>
|
|
#include <detail/include_libstudxml.hpp>
|
|
#include <detail/pole.hpp>
|
|
#include <detail/vector_streambuf.hpp>
|
|
#include <detail/xlsx_consumer.hpp>
|
|
#include <detail/xlsx_producer.hpp>
|
|
|
|
namespace xlnt {
|
|
namespace detail {
|
|
|
|
enum class hash_algorithm
|
|
{
|
|
sha1,
|
|
sha256,
|
|
sha384,
|
|
sha512,
|
|
md5,
|
|
md4,
|
|
md2,
|
|
ripemd128,
|
|
ripemd160,
|
|
whirlpool
|
|
};
|
|
|
|
} // namespace detail
|
|
} // namespace xlnt
|
|
|
|
namespace xml {
|
|
|
|
template <>
|
|
struct value_traits<xlnt::detail::hash_algorithm>
|
|
{
|
|
static xlnt::detail::hash_algorithm parse(std::string hash_algorithm_string, const parser &)
|
|
{
|
|
if (hash_algorithm_string == "SHA1")
|
|
return xlnt::detail::hash_algorithm::sha1;
|
|
else if (hash_algorithm_string == "SHA256")
|
|
return xlnt::detail::hash_algorithm::sha256;
|
|
else if (hash_algorithm_string == "SHA384")
|
|
return xlnt::detail::hash_algorithm::sha384;
|
|
else if (hash_algorithm_string == "SHA512")
|
|
return xlnt::detail::hash_algorithm::sha512;
|
|
else if (hash_algorithm_string == "MD5")
|
|
return xlnt::detail::hash_algorithm::md5;
|
|
else if (hash_algorithm_string == "MD4")
|
|
return xlnt::detail::hash_algorithm::md4;
|
|
else if (hash_algorithm_string == "MD2")
|
|
return xlnt::detail::hash_algorithm::md2;
|
|
else if (hash_algorithm_string == "Ripemd128")
|
|
return xlnt::detail::hash_algorithm::ripemd128;
|
|
else if (hash_algorithm_string == "Ripemd160")
|
|
return xlnt::detail::hash_algorithm::ripemd160;
|
|
else if (hash_algorithm_string == "Whirlpool")
|
|
return xlnt::detail::hash_algorithm::whirlpool;
|
|
throw xlnt::exception(hash_algorithm_string);
|
|
}
|
|
|
|
static std::string serialize(xlnt::detail::hash_algorithm algorithm, const serializer &)
|
|
{
|
|
switch (algorithm)
|
|
{
|
|
case xlnt::detail::hash_algorithm::sha1:
|
|
return "SHA1";
|
|
case xlnt::detail::hash_algorithm::sha256:
|
|
return "SHA256";
|
|
case xlnt::detail::hash_algorithm::sha384:
|
|
return "SHA384";
|
|
case xlnt::detail::hash_algorithm::sha512:
|
|
return "SHA512";
|
|
case xlnt::detail::hash_algorithm::md5:
|
|
return "MD5";
|
|
case xlnt::detail::hash_algorithm::md4:
|
|
return "MD4";
|
|
case xlnt::detail::hash_algorithm::md2:
|
|
return "MD2";
|
|
case xlnt::detail::hash_algorithm::ripemd128:
|
|
return "Ripemd128";
|
|
case xlnt::detail::hash_algorithm::ripemd160:
|
|
return "Ripemd160";
|
|
case xlnt::detail::hash_algorithm::whirlpool:
|
|
return "Whirlpool";
|
|
}
|
|
}
|
|
}; // struct value_traits<>
|
|
|
|
} // namespace xml
|
|
|
|
namespace xlnt {
|
|
namespace detail {
|
|
|
|
struct crypto_helper
|
|
{
|
|
static const std::size_t segment_length;
|
|
|
|
enum class cipher_algorithm
|
|
{
|
|
aes,
|
|
rc2,
|
|
rc4,
|
|
des,
|
|
desx,
|
|
triple_des,
|
|
triple_des_112
|
|
};
|
|
|
|
enum class cipher_chaining
|
|
{
|
|
ecb, // electronic code book
|
|
cbc, // cipher block chaining
|
|
cfb // cipher feedback chaining
|
|
};
|
|
|
|
enum class cipher_direction
|
|
{
|
|
encryption,
|
|
decryption
|
|
};
|
|
|
|
static std::vector<std::uint8_t> aes(const std::vector<std::uint8_t> &key, const std::vector<std::uint8_t> &iv,
|
|
const std::vector<std::uint8_t> &source, cipher_chaining chaining, cipher_direction direction)
|
|
{
|
|
std::vector<std::uint8_t> destination(source.size(), 0);
|
|
|
|
if (direction == cipher_direction::encryption && chaining == cipher_chaining::cbc)
|
|
{
|
|
CryptoPP::AES::Encryption aesEncryption(key.data(), key.size());
|
|
CryptoPP::CBC_Mode_ExternalCipher::Encryption cbcEncryption(aesEncryption, iv.data());
|
|
|
|
CryptoPP::ArraySource as(
|
|
source.data(), source.size(), true, new CryptoPP::StreamTransformationFilter(cbcEncryption,
|
|
new CryptoPP::ArraySink(destination.data(), destination.size()),
|
|
CryptoPP::BlockPaddingSchemeDef::NO_PADDING));
|
|
}
|
|
else if (direction == cipher_direction::decryption && chaining == cipher_chaining::cbc)
|
|
{
|
|
CryptoPP::AES::Decryption aesDecryption(key.data(), key.size());
|
|
CryptoPP::CBC_Mode_ExternalCipher::Decryption cbcDecryption(aesDecryption, iv.data());
|
|
|
|
CryptoPP::ArraySource as(
|
|
source.data(), source.size(), true, new CryptoPP::StreamTransformationFilter(cbcDecryption,
|
|
new CryptoPP::ArraySink(destination.data(), destination.size()),
|
|
CryptoPP::BlockPaddingSchemeDef::NO_PADDING));
|
|
}
|
|
else if (direction == cipher_direction::encryption && chaining == cipher_chaining::ecb)
|
|
{
|
|
CryptoPP::AES::Encryption aesEncryption(key.data(), key.size());
|
|
CryptoPP::ECB_Mode_ExternalCipher::Encryption cbcEncryption(aesEncryption, iv.data());
|
|
|
|
CryptoPP::ArraySource as(
|
|
source.data(), source.size(), true, new CryptoPP::StreamTransformationFilter(cbcEncryption,
|
|
new CryptoPP::ArraySink(destination.data(), destination.size()),
|
|
CryptoPP::BlockPaddingSchemeDef::NO_PADDING));
|
|
}
|
|
else if (direction == cipher_direction::decryption && chaining == cipher_chaining::ecb)
|
|
{
|
|
CryptoPP::AES::Decryption aesDecryption(key.data(), key.size());
|
|
CryptoPP::ECB_Mode_ExternalCipher::Decryption cbcDecryption(aesDecryption, iv.data());
|
|
|
|
CryptoPP::ArraySource as(
|
|
source.data(), source.size(), true, new CryptoPP::StreamTransformationFilter(cbcDecryption,
|
|
new CryptoPP::ArraySink(destination.data(), destination.size()),
|
|
CryptoPP::BlockPaddingSchemeDef::NO_PADDING));
|
|
}
|
|
|
|
return destination;
|
|
}
|
|
|
|
static std::vector<std::uint8_t> decode_base64(const std::string &encoded)
|
|
{
|
|
CryptoPP::Base64Decoder decoder;
|
|
decoder.Put(reinterpret_cast<const std::uint8_t *>(encoded.data()), encoded.size());
|
|
decoder.MessageEnd();
|
|
|
|
std::vector<std::uint8_t> decoded(decoder.MaxRetrievable(), 0);
|
|
decoder.Get(decoded.data(), decoded.size());
|
|
|
|
return decoded;
|
|
}
|
|
|
|
static std::string encode_base64(const std::vector<std::uint8_t> &decoded)
|
|
{
|
|
CryptoPP::Base64Decoder encoder;
|
|
encoder.Put(reinterpret_cast<const std::uint8_t *>(decoded.data()), decoded.size());
|
|
encoder.MessageEnd();
|
|
|
|
std::vector<std::uint8_t> encoded(encoder.MaxRetrievable(), 0);
|
|
encoder.Get(encoded.data(), encoded.size());
|
|
|
|
return std::string(encoded.begin(), encoded.end());
|
|
}
|
|
|
|
static std::vector<std::uint8_t> hash(hash_algorithm algorithm, const std::vector<std::uint8_t> &input)
|
|
{
|
|
std::vector<std::uint8_t> digest;
|
|
|
|
if (algorithm == hash_algorithm::sha512)
|
|
{
|
|
CryptoPP::SHA512 sha512;
|
|
digest.resize(CryptoPP::SHA512::DIGESTSIZE, 0);
|
|
sha512.CalculateDigest(digest.data(), input.data(), input.size());
|
|
}
|
|
else if (algorithm == hash_algorithm::sha1)
|
|
{
|
|
CryptoPP::SHA1 sha1;
|
|
digest.resize(CryptoPP::SHA1::DIGESTSIZE, 0);
|
|
sha1.CalculateDigest(digest.data(), input.data(), input.size());
|
|
}
|
|
|
|
return digest;
|
|
}
|
|
|
|
static std::vector<std::uint8_t> file(POLE::Storage &storage, const std::string &name)
|
|
{
|
|
POLE::Stream stream(&storage, name.c_str());
|
|
if (stream.fail()) return {};
|
|
std::vector<std::uint8_t> bytes(stream.size(), 0);
|
|
stream.read(bytes.data(), static_cast<unsigned long>(bytes.size()));
|
|
return bytes;
|
|
}
|
|
|
|
template <typename T>
|
|
static auto read_int(std::size_t &index, const std::vector<std::uint8_t> &raw_data)
|
|
{
|
|
auto result = *reinterpret_cast<const T *>(&raw_data[index]);
|
|
index += sizeof(T);
|
|
|
|
return result;
|
|
}
|
|
|
|
struct standard_encryption_info
|
|
{
|
|
const std::size_t spin_count = 50000;
|
|
std::size_t block_size;
|
|
std::size_t key_bits;
|
|
std::size_t key_bytes;
|
|
std::size_t hash_size;
|
|
cipher_algorithm cipher;
|
|
cipher_chaining chaining;
|
|
const hash_algorithm hash = hash_algorithm::sha1;
|
|
std::vector<std::uint8_t> salt_value;
|
|
std::vector<std::uint8_t> verifier_hash_input;
|
|
std::vector<std::uint8_t> verifier_hash_value;
|
|
std::vector<std::uint8_t> encrypted_key_value;
|
|
};
|
|
|
|
static std::vector<std::uint8_t> decrypt_xlsx_standard(const std::vector<std::uint8_t> &encryption_info,
|
|
const std::string &password, const std::vector<std::uint8_t> &encrypted_package)
|
|
{
|
|
std::size_t offset = 0;
|
|
|
|
standard_encryption_info info;
|
|
|
|
auto header_length = read_int<std::uint32_t>(offset, encryption_info);
|
|
auto index_at_start = offset;
|
|
/*auto skip_flags = */ read_int<std::uint32_t>(offset, encryption_info);
|
|
/*auto size_extra = */ read_int<std::uint32_t>(offset, encryption_info);
|
|
auto alg_id = read_int<std::uint32_t>(offset, encryption_info);
|
|
|
|
if (alg_id == 0 || alg_id == 0x0000660E || alg_id == 0x0000660F || alg_id == 0x00006610)
|
|
{
|
|
info.cipher = cipher_algorithm::aes;
|
|
}
|
|
else
|
|
{
|
|
throw xlnt::exception("invalid cipher algorithm");
|
|
}
|
|
|
|
auto alg_id_hash = read_int<std::uint32_t>(offset, encryption_info);
|
|
if (alg_id_hash != 0x00008004 && alg_id_hash == 0)
|
|
{
|
|
throw xlnt::exception("invalid hash algorithm");
|
|
}
|
|
|
|
info.key_bits = read_int<std::uint32_t>(offset, encryption_info);
|
|
info.key_bytes = info.key_bits / 8;
|
|
|
|
auto provider_type = read_int<std::uint32_t>(offset, encryption_info);
|
|
if (provider_type != 0 && provider_type != 0x00000018)
|
|
{
|
|
throw xlnt::exception("invalid provider type");
|
|
}
|
|
|
|
read_int<std::uint32_t>(offset, encryption_info); // reserved 1
|
|
if (read_int<std::uint32_t>(offset, encryption_info) != 0) // reserved 2
|
|
{
|
|
throw xlnt::exception("invalid header");
|
|
}
|
|
|
|
const auto csp_name_length = header_length - (offset - index_at_start);
|
|
std::vector<std::uint16_t> csp_name_wide(
|
|
reinterpret_cast<const std::uint16_t *>(&*(encryption_info.begin() + static_cast<std::ptrdiff_t>(offset))),
|
|
reinterpret_cast<const std::uint16_t *>(
|
|
&*(encryption_info.begin() + static_cast<std::ptrdiff_t>(offset + csp_name_length))));
|
|
std::string csp_name(csp_name_wide.begin(), csp_name_wide.end() - 1); // without trailing null
|
|
if (csp_name != "Microsoft Enhanced RSA and AES Cryptographic Provider (Prototype)"
|
|
&& csp_name != "Microsoft Enhanced RSA and AES Cryptographic Provider")
|
|
{
|
|
throw xlnt::exception("invalid cryptographic provider");
|
|
}
|
|
offset += csp_name_length;
|
|
|
|
const auto salt_size = read_int<std::uint32_t>(offset, encryption_info);
|
|
std::vector<std::uint8_t> salt(encryption_info.begin() + static_cast<std::ptrdiff_t>(offset),
|
|
encryption_info.begin() + static_cast<std::ptrdiff_t>(offset + salt_size));
|
|
offset += salt_size;
|
|
|
|
static const auto verifier_size = std::size_t(16);
|
|
std::vector<std::uint8_t> verifier_hash_input(encryption_info.begin() + static_cast<std::ptrdiff_t>(offset),
|
|
encryption_info.begin() + static_cast<std::ptrdiff_t>(offset + verifier_size));
|
|
offset += verifier_size;
|
|
|
|
const auto verifier_hash_size = read_int<std::uint32_t>(offset, encryption_info);
|
|
std::vector<std::uint8_t> verifier_hash_value(encryption_info.begin() + static_cast<std::ptrdiff_t>(offset),
|
|
encryption_info.begin() + static_cast<std::ptrdiff_t>(offset + verifier_hash_size));
|
|
offset += verifier_hash_size;
|
|
|
|
// begin key generation algorithm
|
|
|
|
// H_0 = H(salt + password)
|
|
auto salt_plus_password = salt;
|
|
std::vector<std::uint16_t> password_wide(password.begin(), password.end());
|
|
std::for_each(password_wide.begin(), password_wide.end(), [&salt_plus_password](std::uint16_t c) {
|
|
salt_plus_password.insert(salt_plus_password.end(), reinterpret_cast<char *>(&c),
|
|
reinterpret_cast<char *>(&c) + sizeof(std::uint16_t));
|
|
});
|
|
std::vector<std::uint8_t> h_0 = hash(info.hash, salt_plus_password);
|
|
|
|
// H_n = H(iterator + H_n-1)
|
|
std::vector<std::uint8_t> iterator_plus_h_n(4, 0);
|
|
iterator_plus_h_n.insert(iterator_plus_h_n.end(), h_0.begin(), h_0.end());
|
|
std::uint32_t &iterator = *reinterpret_cast<std::uint32_t *>(iterator_plus_h_n.data());
|
|
std::vector<std::uint8_t> h_n;
|
|
for (iterator = 0; iterator < info.spin_count; ++iterator)
|
|
{
|
|
h_n = hash(info.hash, iterator_plus_h_n);
|
|
std::copy(h_n.begin(), h_n.end(), iterator_plus_h_n.begin() + 4);
|
|
}
|
|
|
|
// H_final = H(H_n + block)
|
|
auto h_n_plus_block = h_n;
|
|
const std::uint32_t block_number = 0;
|
|
h_n_plus_block.insert(h_n_plus_block.end(), reinterpret_cast<const std::uint8_t *>(&block_number),
|
|
reinterpret_cast<const std::uint8_t *>(&block_number) + sizeof(std::uint32_t));
|
|
auto h_final = hash(info.hash, h_n_plus_block);
|
|
|
|
// X1 = H(h_final ^ 0x36)
|
|
std::vector<std::uint8_t> buffer(64, 0x36);
|
|
for (std::size_t i = 0; i < h_final.size(); ++i)
|
|
{
|
|
buffer[i] = static_cast<std::uint8_t>(0x36 ^ h_final[i]);
|
|
}
|
|
auto X1 = hash(info.hash, buffer);
|
|
|
|
// X2 = H(h_final ^ 0x5C)
|
|
buffer.assign(64, 0x5c);
|
|
for (std::size_t i = 0; i < h_final.size(); ++i)
|
|
{
|
|
buffer[i] = static_cast<std::uint8_t>(0x5c ^ h_final[i]);
|
|
}
|
|
auto X2 = hash(info.hash, buffer);
|
|
|
|
auto X3 = X1;
|
|
X3.insert(X3.end(), X2.begin(), X2.end());
|
|
|
|
auto key_derived =
|
|
std::vector<std::uint8_t>(X3.begin(), X3.begin() + static_cast<std::ptrdiff_t>(info.key_bytes));
|
|
|
|
// todo: verify here
|
|
|
|
std::size_t package_offset = 0;
|
|
auto decrypted_size = static_cast<std::size_t>(read_int<std::uint64_t>(package_offset, encrypted_package));
|
|
auto decrypted =
|
|
aes(key_derived, {}, std::vector<std::uint8_t>(encrypted_package.begin() + 8, encrypted_package.end()),
|
|
cipher_chaining::ecb, cipher_direction::decryption);
|
|
decrypted.resize(decrypted_size);
|
|
|
|
return decrypted;
|
|
}
|
|
|
|
struct agile_encryption_info
|
|
{
|
|
// key data
|
|
struct
|
|
{
|
|
std::size_t salt_size;
|
|
std::size_t block_size;
|
|
std::size_t key_bits;
|
|
std::size_t hash_size;
|
|
std::string cipher_algorithm;
|
|
std::string cipher_chaining;
|
|
std::string hash_algorithm;
|
|
std::vector<std::uint8_t> salt_value;
|
|
} key_data;
|
|
|
|
struct
|
|
{
|
|
std::vector<std::uint8_t> hmac_key;
|
|
std::vector<std::uint8_t> hmac_value;
|
|
} data_integrity;
|
|
|
|
struct
|
|
{
|
|
std::size_t spin_count;
|
|
std::size_t salt_size;
|
|
std::size_t block_size;
|
|
std::size_t key_bits;
|
|
std::size_t hash_size;
|
|
std::string cipher_algorithm;
|
|
std::string cipher_chaining;
|
|
hash_algorithm hash;
|
|
std::vector<std::uint8_t> salt_value;
|
|
std::vector<std::uint8_t> verifier_hash_input;
|
|
std::vector<std::uint8_t> verifier_hash_value;
|
|
std::vector<std::uint8_t> encrypted_key_value;
|
|
} key_encryptor;
|
|
};
|
|
|
|
static agile_encryption_info generate_agile_encryption_info(const std::string &password)
|
|
{
|
|
agile_encryption_info result;
|
|
result.key_data.salt_value.assign(password.begin(), password.end());
|
|
return result;
|
|
}
|
|
|
|
static std::vector<std::uint8_t> write_agile_encryption_info(const std::string &password)
|
|
{
|
|
static const auto &xmlns = xlnt::constants::namespace_("encryption");
|
|
static const auto &xmlns_p = xlnt::constants::namespace_("encryption-password");
|
|
|
|
std::vector<std::uint8_t> encryption_info;
|
|
xlnt::detail::vector_ostreambuf encryption_info_buffer(encryption_info);
|
|
std::ostream encryption_info_stream(&encryption_info_buffer);
|
|
xml::serializer serializer(encryption_info_stream, "EncryptionInfo");
|
|
|
|
agile_encryption_info result = generate_agile_encryption_info(password);
|
|
|
|
serializer.start_element(xmlns, "encryption");
|
|
|
|
serializer.start_element(xmlns, "keyData");
|
|
serializer.attribute("saltSize", result.key_data.salt_size);
|
|
serializer.attribute("blockSize", result.key_data.block_size);
|
|
serializer.attribute("keyBits", result.key_data.key_bits);
|
|
serializer.attribute("hashSize", result.key_data.hash_size);
|
|
serializer.attribute("cipherAlgorithm", result.key_data.cipher_algorithm);
|
|
serializer.attribute("cipherChaining", result.key_data.cipher_chaining);
|
|
serializer.attribute("hashAlgorithm", result.key_data.hash_algorithm);
|
|
serializer.attribute("saltValue", encode_base64(result.key_data.salt_value));
|
|
serializer.end_element(xmlns, "keyData");
|
|
|
|
serializer.start_element(xmlns, "dataIntegrity");
|
|
serializer.attribute("encryptedHmacKey", encode_base64(result.data_integrity.hmac_key));
|
|
serializer.attribute("encryptedHmacValue", encode_base64(result.data_integrity.hmac_value));
|
|
serializer.end_element(xmlns, "dataIntegrity");
|
|
|
|
serializer.start_element(xmlns, "keyEncryptors");
|
|
serializer.start_element(xmlns, "keyEncryptor");
|
|
serializer.attribute("uri", "");
|
|
serializer.start_element(xmlns_p, "encryptedKey");
|
|
serializer.attribute("spinCount", result.key_encryptor.spin_count);
|
|
serializer.attribute("saltSize", result.key_encryptor.salt_size);
|
|
serializer.attribute("blockSize", result.key_encryptor.block_size);
|
|
serializer.attribute("keyBits", result.key_encryptor.key_bits);
|
|
serializer.attribute("hashSize", result.key_encryptor.hash_size);
|
|
serializer.attribute("cipherAlgorithm", result.key_encryptor.cipher_algorithm);
|
|
serializer.attribute("cipherChaining", result.key_encryptor.cipher_chaining);
|
|
serializer.attribute("hashAlgorithm", result.key_encryptor.hash);
|
|
serializer.attribute("saltValue", encode_base64(result.key_encryptor.salt_value));
|
|
serializer.attribute("encryptedVerifierHashInput", encode_base64(result.key_encryptor.verifier_hash_input));
|
|
serializer.attribute("encryptedVerifierHashValue", encode_base64(result.key_encryptor.verifier_hash_value));
|
|
serializer.attribute("encryptedKeyValue", encode_base64(result.key_encryptor.encrypted_key_value));
|
|
serializer.end_element(xmlns_p, "encryptedKey");
|
|
serializer.end_element(xmlns, "keyEncryptor");
|
|
serializer.end_element(xmlns, "keyEncryptors");
|
|
|
|
serializer.end_element(xmlns, "encryption");
|
|
|
|
return encryption_info;
|
|
}
|
|
|
|
static std::vector<std::uint8_t> decrypt_xlsx_agile(const std::vector<std::uint8_t> &encryption_info,
|
|
const std::string &password, const std::vector<std::uint8_t> &encrypted_package)
|
|
{
|
|
static const auto &xmlns = xlnt::constants::namespace_("encryption");
|
|
static const auto &xmlns_p = xlnt::constants::namespace_("encryption-password");
|
|
// static const auto &xmlns_c = xlnt::constants::namespace_("encryption-certificate");
|
|
|
|
agile_encryption_info result;
|
|
|
|
xml::parser parser(encryption_info.data(), encryption_info.size(), "EncryptionInfo");
|
|
|
|
parser.next_expect(xml::parser::event_type::start_element, xmlns, "encryption");
|
|
|
|
parser.next_expect(xml::parser::event_type::start_element, xmlns, "keyData");
|
|
result.key_data.salt_size = parser.attribute<std::size_t>("saltSize");
|
|
result.key_data.block_size = parser.attribute<std::size_t>("blockSize");
|
|
result.key_data.key_bits = parser.attribute<std::size_t>("keyBits");
|
|
result.key_data.hash_size = parser.attribute<std::size_t>("hashSize");
|
|
result.key_data.cipher_algorithm = parser.attribute("cipherAlgorithm");
|
|
result.key_data.cipher_chaining = parser.attribute("cipherChaining");
|
|
result.key_data.hash_algorithm = parser.attribute("hashAlgorithm");
|
|
result.key_data.salt_value = decode_base64(parser.attribute("saltValue"));
|
|
parser.next_expect(xml::parser::event_type::end_element, xmlns, "keyData");
|
|
|
|
parser.next_expect(xml::parser::event_type::start_element, xmlns, "dataIntegrity");
|
|
result.data_integrity.hmac_key = decode_base64(parser.attribute("encryptedHmacKey"));
|
|
result.data_integrity.hmac_value = decode_base64(parser.attribute("encryptedHmacValue"));
|
|
parser.next_expect(xml::parser::event_type::end_element, xmlns, "dataIntegrity");
|
|
|
|
parser.next_expect(xml::parser::event_type::start_element, xmlns, "keyEncryptors");
|
|
parser.next_expect(xml::parser::event_type::start_element, xmlns, "keyEncryptor");
|
|
parser.attribute("uri");
|
|
bool any_password_key = false;
|
|
|
|
while (parser.peek() != xml::parser::event_type::end_element)
|
|
{
|
|
parser.next_expect(xml::parser::event_type::start_element);
|
|
|
|
if (parser.namespace_() == xmlns_p && parser.name() == "encryptedKey")
|
|
{
|
|
any_password_key = true;
|
|
result.key_encryptor.spin_count = parser.attribute<std::size_t>("spinCount");
|
|
result.key_encryptor.salt_size = parser.attribute<std::size_t>("saltSize");
|
|
result.key_encryptor.block_size = parser.attribute<std::size_t>("blockSize");
|
|
result.key_encryptor.key_bits = parser.attribute<std::size_t>("keyBits");
|
|
result.key_encryptor.hash_size = parser.attribute<std::size_t>("hashSize");
|
|
result.key_encryptor.cipher_algorithm = parser.attribute("cipherAlgorithm");
|
|
result.key_encryptor.cipher_chaining = parser.attribute("cipherChaining");
|
|
|
|
auto hash_algorithm_string = parser.attribute("hashAlgorithm");
|
|
if (hash_algorithm_string == "SHA512")
|
|
{
|
|
result.key_encryptor.hash = hash_algorithm::sha512;
|
|
}
|
|
else if (hash_algorithm_string == "SHA1")
|
|
{
|
|
result.key_encryptor.hash = hash_algorithm::sha1;
|
|
}
|
|
else if (hash_algorithm_string == "SHA256")
|
|
{
|
|
result.key_encryptor.hash = hash_algorithm::sha256;
|
|
}
|
|
else if (hash_algorithm_string == "SHA384")
|
|
{
|
|
result.key_encryptor.hash = hash_algorithm::sha384;
|
|
}
|
|
|
|
result.key_encryptor.salt_value = decode_base64(parser.attribute("saltValue"));
|
|
result.key_encryptor.verifier_hash_input =
|
|
decode_base64(parser.attribute("encryptedVerifierHashInput"));
|
|
result.key_encryptor.verifier_hash_value =
|
|
decode_base64(parser.attribute("encryptedVerifierHashValue"));
|
|
result.key_encryptor.encrypted_key_value = decode_base64(parser.attribute("encryptedKeyValue"));
|
|
}
|
|
else
|
|
{
|
|
throw xlnt::unsupported("other encryption key types not supported");
|
|
}
|
|
|
|
parser.next_expect(xml::parser::event_type::end_element);
|
|
}
|
|
|
|
if (!any_password_key)
|
|
{
|
|
throw "no password key in keyEncryptors";
|
|
}
|
|
|
|
parser.next_expect(xml::parser::event_type::end_element, xmlns, "keyEncryptor");
|
|
parser.next_expect(xml::parser::event_type::end_element, xmlns, "keyEncryptors");
|
|
|
|
parser.next_expect(xml::parser::event_type::end_element, xmlns, "encryption");
|
|
|
|
// begin key generation algorithm
|
|
|
|
// H_0 = H(salt + password)
|
|
auto salt_plus_password = result.key_encryptor.salt_value;
|
|
std::vector<std::uint16_t> password_wide(password.begin(), password.end());
|
|
|
|
std::for_each(password_wide.begin(), password_wide.end(), [&salt_plus_password](std::uint16_t c) {
|
|
salt_plus_password.insert(salt_plus_password.end(), reinterpret_cast<char *>(&c),
|
|
reinterpret_cast<char *>(&c) + sizeof(std::uint16_t));
|
|
});
|
|
|
|
auto h_0 = hash(result.key_encryptor.hash, salt_plus_password);
|
|
|
|
// H_n = H(iterator + H_n-1)
|
|
std::vector<std::uint8_t> iterator_plus_h_n(4, 0);
|
|
iterator_plus_h_n.insert(iterator_plus_h_n.end(), h_0.begin(), h_0.end());
|
|
std::uint32_t &iterator = *reinterpret_cast<std::uint32_t *>(iterator_plus_h_n.data());
|
|
std::vector<std::uint8_t> h_n;
|
|
|
|
for (iterator = 0; iterator < result.key_encryptor.spin_count; ++iterator)
|
|
{
|
|
h_n = hash(result.key_encryptor.hash, iterator_plus_h_n);
|
|
std::copy(h_n.begin(), h_n.end(), iterator_plus_h_n.begin() + 4);
|
|
}
|
|
|
|
static const std::size_t block_size = 8;
|
|
|
|
auto calculate_block = [&result](const std::vector<std::uint8_t> &raw_key,
|
|
const std::array<std::uint8_t, block_size> &block, const std::vector<std::uint8_t> &encrypted) {
|
|
auto combined = raw_key;
|
|
combined.insert(combined.end(), block.begin(), block.end());
|
|
auto key = hash(result.key_encryptor.hash, combined);
|
|
key.resize(result.key_encryptor.key_bits / 8);
|
|
return aes(
|
|
key, result.key_encryptor.salt_value, encrypted, cipher_chaining::cbc, cipher_direction::decryption);
|
|
};
|
|
|
|
const std::array<std::uint8_t, block_size> input_block_key = {{0xfe, 0xa7, 0xd2, 0x76, 0x3b, 0x4b, 0x9e, 0x79}};
|
|
auto hash_input = calculate_block(h_n, input_block_key, result.key_encryptor.verifier_hash_input);
|
|
auto calculated_verifier = hash(result.key_encryptor.hash, hash_input);
|
|
|
|
const std::array<std::uint8_t, block_size> verifier_block_key = {
|
|
{0xd7, 0xaa, 0x0f, 0x6d, 0x30, 0x61, 0x34, 0x4e}};
|
|
auto expected_verifier = calculate_block(h_n, verifier_block_key, result.key_encryptor.verifier_hash_value);
|
|
expected_verifier.resize(calculated_verifier.size());
|
|
|
|
if (calculated_verifier.size() != expected_verifier.size()
|
|
|| std::mismatch(calculated_verifier.begin(), calculated_verifier.end(), expected_verifier.begin(),
|
|
expected_verifier.end())
|
|
!= std::make_pair(calculated_verifier.end(), expected_verifier.end()))
|
|
{
|
|
throw xlnt::exception("bad password");
|
|
}
|
|
|
|
const std::array<std::uint8_t, block_size> key_value_block_key = {
|
|
{0x14, 0x6e, 0x0b, 0xe7, 0xab, 0xac, 0xd0, 0xd6}};
|
|
auto key = calculate_block(h_n, key_value_block_key, result.key_encryptor.encrypted_key_value);
|
|
|
|
auto salt_size = result.key_data.salt_size;
|
|
auto salt_with_block_key = result.key_data.salt_value;
|
|
salt_with_block_key.resize(salt_size + sizeof(std::uint32_t), 0);
|
|
|
|
auto &segment = *reinterpret_cast<std::uint32_t *>(salt_with_block_key.data() + salt_size);
|
|
auto total_size = static_cast<std::size_t>(*reinterpret_cast<const std::uint64_t *>(encrypted_package.data()));
|
|
|
|
std::vector<std::uint8_t> encrypted_segment(segment_length, 0);
|
|
std::vector<std::uint8_t> decrypted_package;
|
|
decrypted_package.reserve(encrypted_package.size() - 8);
|
|
|
|
for (std::size_t i = 8; i < encrypted_package.size(); i += segment_length)
|
|
{
|
|
auto iv = hash(result.key_encryptor.hash, salt_with_block_key);
|
|
iv.resize(16);
|
|
|
|
auto segment_begin = encrypted_package.begin() + static_cast<std::ptrdiff_t>(i);
|
|
auto current_segment_length = std::min(segment_length, encrypted_package.size() - i);
|
|
auto segment_end = encrypted_package.begin() + static_cast<std::ptrdiff_t>(i + current_segment_length);
|
|
encrypted_segment.assign(segment_begin, segment_end);
|
|
auto decrypted_segment =
|
|
aes(key, iv, encrypted_segment, cipher_chaining::cbc, cipher_direction::decryption);
|
|
decrypted_segment.resize(current_segment_length);
|
|
|
|
decrypted_package.insert(decrypted_package.end(), decrypted_segment.begin(), decrypted_segment.end());
|
|
|
|
++segment;
|
|
}
|
|
|
|
decrypted_package.resize(total_size);
|
|
|
|
return decrypted_package;
|
|
}
|
|
|
|
static std::vector<std::uint8_t> decrypt_xlsx(const std::vector<std::uint8_t> &bytes, const std::string &password)
|
|
{
|
|
if (bytes.empty())
|
|
{
|
|
throw xlnt::exception("empty file");
|
|
}
|
|
|
|
std::vector<char> as_chars(bytes.begin(), bytes.end());
|
|
POLE::Storage storage(as_chars.data(), static_cast<unsigned long>(bytes.size()));
|
|
|
|
if (!storage.open())
|
|
{
|
|
throw xlnt::exception("not an ole compound file");
|
|
}
|
|
|
|
auto encrypted_package = file(storage, "EncryptedPackage");
|
|
auto encryption_info = file(storage, "EncryptionInfo");
|
|
|
|
std::size_t index = 0;
|
|
|
|
auto version_major = read_int<std::uint16_t>(index, encryption_info);
|
|
auto version_minor = read_int<std::uint16_t>(index, encryption_info);
|
|
auto encryption_flags = read_int<std::uint32_t>(index, encryption_info);
|
|
|
|
// get rid of header
|
|
encryption_info.erase(encryption_info.begin(), encryption_info.begin() + static_cast<std::ptrdiff_t>(index));
|
|
|
|
// version 4.4 is agile
|
|
if (version_major == 4 && version_minor == 4)
|
|
{
|
|
if (encryption_flags != 0x40)
|
|
{
|
|
throw xlnt::exception("bad header");
|
|
}
|
|
|
|
return decrypt_xlsx_agile(encryption_info, password, encrypted_package);
|
|
}
|
|
|
|
// not agile, only try to decrypt versions 3.2 and 4.2
|
|
if (version_minor != 2 || (version_major != 2 && version_major != 3 && version_major != 4))
|
|
{
|
|
throw xlnt::exception("unsupported encryption version");
|
|
}
|
|
|
|
if ((encryption_flags & 0b00000011) != 0) // Reserved1 and Reserved2, MUST be 0
|
|
{
|
|
throw xlnt::exception("bad header");
|
|
}
|
|
|
|
if ((encryption_flags & 0b00000100) == 0 // fCryptoAPI
|
|
|| (encryption_flags & 0b00010000) != 0) // fExternal
|
|
{
|
|
throw xlnt::exception("extensible encryption is not supported");
|
|
}
|
|
|
|
if ((encryption_flags & 0b00100000) == 0) // fAES
|
|
{
|
|
throw xlnt::exception("not an OOXML document");
|
|
}
|
|
|
|
return decrypt_xlsx_standard(encryption_info, password, encrypted_package);
|
|
}
|
|
|
|
static std::vector<std::uint8_t> encrypt_xlsx(const std::vector<std::uint8_t> &bytes, const std::string &password)
|
|
{
|
|
if (bytes.empty())
|
|
{
|
|
throw xlnt::exception("empty file");
|
|
}
|
|
|
|
generate_agile_encryption_info(password);
|
|
|
|
return {};
|
|
}
|
|
};
|
|
|
|
const std::size_t crypto_helper::segment_length = 4096;
|
|
|
|
void xlsx_consumer::read(std::istream &source, const std::string &password)
|
|
{
|
|
std::vector<std::uint8_t> data((std::istreambuf_iterator<char>(source)), (std::istreambuf_iterator<char>()));
|
|
const auto decrypted = crypto_helper::decrypt_xlsx(data, password);
|
|
vector_istreambuf decrypted_buffer(decrypted);
|
|
std::istream decrypted_stream(&decrypted_buffer);
|
|
read(decrypted_stream);
|
|
}
|
|
|
|
void xlsx_producer::write(std::ostream &destination, const std::string &password)
|
|
{
|
|
std::vector<std::uint8_t> decrypted;
|
|
|
|
{
|
|
vector_ostreambuf decrypted_buffer(decrypted);
|
|
std::ostream decrypted_stream(&decrypted_buffer);
|
|
write(decrypted_stream);
|
|
}
|
|
|
|
const auto encrypted = crypto_helper::encrypt_xlsx(decrypted, password);
|
|
vector_istreambuf encrypted_buffer(encrypted);
|
|
|
|
destination << &encrypted_buffer;
|
|
}
|
|
|
|
} // namespace detail
|
|
} // namespace xlnt
|