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/*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <cassert>
#include <algorithm>
#include "cipher_ossl.hpp"
#include "utils.h"
#include "types.h"
#include <openssl/err.h>
static const id_str_pair cipher_mode_map[] = {
{PGP_CIPHER_MODE_CBC, "CBC"},
{PGP_CIPHER_MODE_OCB, "OCB"},
{0, NULL},
};
static const id_str_pair cipher_map[] = {
{PGP_SA_AES_128, "AES-128"},
{PGP_SA_AES_256, "AES-256"},
{PGP_SA_IDEA, "IDEA"},
{0, NULL},
};
EVP_CIPHER_CTX *
Cipher_OpenSSL::create(pgp_symm_alg_t alg,
const std::string &name,
bool encrypt,
size_t tag_size,
bool disable_padding)
{
#if !defined(ENABLE_IDEA)
if (alg == PGP_SA_IDEA) {
RNP_LOG("IDEA support has been disabled");
return nullptr;
}
#endif
#if !defined(ENABLE_BLOWFISH)
if (alg == PGP_SA_BLOWFISH) {
RNP_LOG("Blowfish support has been disabled");
return nullptr;
}
#endif
#if !defined(ENABLE_CAST5)
if (alg == PGP_SA_CAST5) {
RNP_LOG("CAST5 support has been disabled");
return nullptr;
}
#endif
const EVP_CIPHER *cipher = EVP_get_cipherbyname(name.c_str());
if (!cipher) {
RNP_LOG("Unsupported cipher: %s", name.c_str());
return nullptr;
}
EVP_CIPHER_CTX *ctx = EVP_CIPHER_CTX_new();
if (!ctx) {
RNP_LOG("Failed to create cipher context: %lu", ERR_peek_last_error());
return nullptr;
}
if (EVP_CipherInit_ex(ctx, cipher, NULL, NULL, NULL, encrypt ? 1 : 0) != 1) {
RNP_LOG("Failed to initialize cipher: %lu", ERR_peek_last_error());
EVP_CIPHER_CTX_free(ctx);
return nullptr;
}
// set tag size
if (encrypt && tag_size) {
if (EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_TAG, tag_size, NULL) != 1) {
RNP_LOG("Failed to set AEAD tag length: %lu", ERR_peek_last_error());
EVP_CIPHER_CTX_free(ctx);
return nullptr;
}
}
if (disable_padding) {
EVP_CIPHER_CTX_set_padding(ctx, 0);
}
return ctx;
}
static std::string
make_name(pgp_symm_alg_t cipher, pgp_cipher_mode_t mode)
{
const char *cipher_string = id_str_pair::lookup(cipher_map, cipher, NULL);
const char *mode_string = id_str_pair::lookup(cipher_mode_map, mode, NULL);
if (!cipher_string || !mode_string) {
return "";
}
return std::string(cipher_string) + "-" + mode_string;
}
std::unique_ptr<Cipher_OpenSSL>
Cipher_OpenSSL::encryption(pgp_symm_alg_t cipher,
pgp_cipher_mode_t mode,
size_t tag_size,
bool disable_padding)
{
EVP_CIPHER_CTX *ossl_ctx =
create(cipher, make_name(cipher, mode), true, tag_size, disable_padding);
if (!ossl_ctx) {
return NULL;
}
return std::unique_ptr<Cipher_OpenSSL>(new (std::nothrow)
Cipher_OpenSSL(cipher, ossl_ctx, tag_size, true));
}
std::unique_ptr<Cipher_OpenSSL>
Cipher_OpenSSL::decryption(pgp_symm_alg_t cipher,
pgp_cipher_mode_t mode,
size_t tag_size,
bool disable_padding)
{
EVP_CIPHER_CTX *ossl_ctx =
create(cipher, make_name(cipher, mode), false, tag_size, disable_padding);
if (!ossl_ctx) {
return NULL;
}
return std::unique_ptr<Cipher_OpenSSL>(
new (std::nothrow) Cipher_OpenSSL(cipher, ossl_ctx, tag_size, false));
}
bool
Cipher_OpenSSL::set_key(const uint8_t *key, size_t key_length)
{
assert(key_length <= INT_MAX);
return EVP_CIPHER_CTX_set_key_length(m_ctx, (int) key_length) == 1 &&
EVP_CipherInit_ex(m_ctx, NULL, NULL, key, NULL, -1) == 1;
}
bool
Cipher_OpenSSL::set_iv(const uint8_t *iv, size_t iv_length)
{
assert(iv_length <= INT_MAX);
// set IV len for AEAD modes
if (m_tag_size &&
EVP_CIPHER_CTX_ctrl(m_ctx, EVP_CTRL_AEAD_SET_IVLEN, (int) iv_length, NULL) != 1) {
RNP_LOG("Failed to set AEAD IV length: %lu", ERR_peek_last_error());
return false;
}
if (EVP_CIPHER_CTX_iv_length(m_ctx) != (int) iv_length) {
RNP_LOG("IV length mismatch");
return false;
}
if (EVP_CipherInit_ex(m_ctx, NULL, NULL, NULL, iv, -1) != 1) {
RNP_LOG("Failed to set IV: %lu", ERR_peek_last_error());
}
return true;
}
bool
Cipher_OpenSSL::set_ad(const uint8_t *ad, size_t ad_length)
{
assert(m_tag_size);
int outlen = 0;
if (EVP_CipherUpdate(m_ctx, NULL, &outlen, ad, ad_length) != 1) {
RNP_LOG("Failed to set AD: %lu", ERR_peek_last_error());
return false;
}
return true;
}
size_t
Cipher_OpenSSL::update_granularity() const
{
return (size_t) EVP_CIPHER_CTX_block_size(m_ctx);
}
bool
Cipher_OpenSSL::update(uint8_t * output,
size_t output_length,
size_t * output_written,
const uint8_t *input,
size_t input_length,
size_t * input_consumed)
{
if (input_length > INT_MAX) {
return false;
}
*input_consumed = 0;
*output_written = 0;
if (input_length == 0) {
return true;
}
int outl = 0;
if (EVP_CipherUpdate(m_ctx, output, &outl, input, (int) input_length) != 1) {
RNP_LOG("EVP_CipherUpdate failed: %lu", ERR_peek_last_error());
return false;
}
assert((size_t) outl < output_length);
*input_consumed = input_length;
*output_written = (size_t) outl;
return true;
}
bool
Cipher_OpenSSL::finish(uint8_t * output,
size_t output_length,
size_t * output_written,
const uint8_t *input,
size_t input_length,
size_t * input_consumed)
{
if (input_length > INT_MAX) {
return false;
}
if (!m_encrypt && input_length < m_tag_size) {
RNP_LOG("Insufficient input for final block (missing tag)");
return false;
}
*input_consumed = 0;
*output_written = 0;
if (!m_encrypt && m_tag_size) {
// set the tag from the end of the ciphertext
if (EVP_CIPHER_CTX_ctrl(m_ctx,
EVP_CTRL_AEAD_SET_TAG,
m_tag_size,
const_cast<uint8_t *>(input) + input_length - m_tag_size) !=
1) {
RNP_LOG("Failed to set expected AEAD tag: %lu", ERR_peek_last_error());
return false;
}
size_t ats = std::min(m_tag_size, input_length);
input_length -= ats; // m_tag_size;
*input_consumed += ats; // m_tag_size;
}
int outl = 0;
if (EVP_CipherUpdate(m_ctx, output, &outl, input, (int) input_length) != 1) {
RNP_LOG("EVP_CipherUpdate failed: %lu", ERR_peek_last_error());
return false;
}
input += input_length;
*input_consumed += input_length;
output += outl;
*output_written += (size_t) outl;
if (EVP_CipherFinal_ex(m_ctx, output, &outl) != 1) {
RNP_LOG("EVP_CipherFinal_ex failed: %lu", ERR_peek_last_error());
return false;
}
*output_written += (size_t) outl;
output += (size_t) outl;
if (m_encrypt && m_tag_size) {
// append the tag
if (EVP_CIPHER_CTX_ctrl(m_ctx, EVP_CTRL_AEAD_GET_TAG, m_tag_size, output) != 1) {
RNP_LOG("Failed to append AEAD tag: %lu", ERR_peek_last_error());
return false;
}
*output_written += m_tag_size;
}
return true;
}
Cipher_OpenSSL::Cipher_OpenSSL(pgp_symm_alg_t alg,
EVP_CIPHER_CTX *ctx,
size_t tag_size,
bool encrypt)
: Cipher(alg), m_ctx(ctx), m_tag_size(tag_size), m_encrypt(encrypt)
{
m_block_size = EVP_CIPHER_CTX_block_size(m_ctx);
}
Cipher_OpenSSL::~Cipher_OpenSSL()
{
EVP_CIPHER_CTX_free(m_ctx);
}