include/crypto/akcipher.h

/*
 * QEMU Crypto asymmetric algorithms
 *
 * Copyright (c) 2022 Bytedance
 * Author: zhenwei pi <pizhenwei@bytedance.com>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
 *
 */

#ifndef QCRYPTO_AKCIPHER_H
#define QCRYPTO_AKCIPHER_H

#include "qapi/qapi-types-crypto.h"

typedef struct QCryptoAkCipher QCryptoAkCipher;

/**
 * qcrypto_akcipher_supports:
 * @opts: the asymmetric key algorithm and related options
 *
 * Determine if asymmetric key cipher decribed with @opts is
 * supported by the current configured build
 *
 * Returns: true if it is supported, false otherwise.
 */
bool qcrypto_akcipher_supports(QCryptoAkCipherOptions *opts);

/**
 * qcrypto_akcipher_new:
 * @opts: specify the algorithm and the related arguments
 * @type: private or public key type
 * @key: buffer to store the key
 * @key_len: the length of key buffer
 * @errp: error pointer
 *
 * Create akcipher context
 *
 * Returns: On success, a new QCryptoAkCipher initialized with @opt
 * is created and returned, otherwise NULL is returned.
 */

QCryptoAkCipher *qcrypto_akcipher_new(const QCryptoAkCipherOptions *opts,
                                      QCryptoAkCipherKeyType type,
                                      const uint8_t *key, size_t key_len,
                                      Error **errp);

/**
 * qcrypto_akcipher_encrypt:
 * @akcipher: akcipher context
 * @in: plaintext pending to be encrypted
 * @in_len: length of plaintext, less or equal to the size reported
 *          by a call to qcrypto_akcipher_max_plaintext_len()
 * @out: buffer to store the ciphertext
 * @out_len: length of ciphertext, less or equal to the size reported
 *           by a call to qcrypto_akcipher_max_ciphertext_len()
 * @errp: error pointer
 *
 * Encrypt @in and write ciphertext into @out
 *
 * Returns: length of ciphertext if encrypt succeed,
 *          otherwise -1 is returned
 */
int qcrypto_akcipher_encrypt(QCryptoAkCipher *akcipher,
                             const void *in, size_t in_len,
                             void *out, size_t out_len, Error **errp);

/**
 * qcrypto_akcipher_decrypt:
 * @akcipher: akcipher context
 * @in: ciphertext to be decrypted
 * @in_len: the length of ciphertext, less or equal to the size reported
 *          by a call to qcrypto_akcipher_max_ciphertext_len()
 * @out: buffer to store the plaintext
 * @out_len: length of the plaintext buffer, less or equal to the size
 *           reported by a call to qcrypto_akcipher_max_plaintext_len()
 * @errp: error pointer
 *
 * Decrypt @in and write plaintext into @out
 *
 * Returns: length of plaintext if decrypt succeed,
 *          otherwise -1 is returned
 */
int qcrypto_akcipher_decrypt(QCryptoAkCipher *akcipher,
                             const void *in, size_t in_len,
                             void *out, size_t out_len, Error **errp);

/**
 * qcrypto_akcipher_sign:
 * @akcipher: akcipher context
 * @in: data to be signed
 * @in_len: the length of data, less or equal to the size reported
 *          by a call to qcrypto_akcipher_max_dgst_len()
 * @out: buffer to store the signature
 * @out_len: length of the signature buffer, less or equal to the size
 *           by a call to qcrypto_akcipher_max_signature_len()
 * @errp: error pointer
 *
 * Generate signature for @in, write into @out
 *
 * Returns: length of signature if succeed,
 *          otherwise -1 is returned
 */
int qcrypto_akcipher_sign(QCryptoAkCipher *akcipher,
                          const void *in, size_t in_len,
                          void *out, size_t out_len, Error **errp);

/**
 * qcrypto_akcipher_verify:
 * @akcipher: akcipher context
 * @in: pointer to the signature
 * @in_len: length of signature, ess or equal to the size reported
 *          by a call to qcrypto_akcipher_max_signature_len()
 * @in2: pointer to original data
 * @in2_len: the length of original data, less or equal to the size
 *           by a call to qcrypto_akcipher_max_dgst_len()
 * @errp: error pointer
 *
 * Verify @in and @in2 match or not
 *
 * Returns: 0 for succeed,
 *          otherwise -1 is returned
 */
int qcrypto_akcipher_verify(QCryptoAkCipher *akcipher,
                            const void *in, size_t in_len,
                            const void *in2, size_t in2_len, Error **errp);

int qcrypto_akcipher_max_plaintext_len(QCryptoAkCipher *akcipher);

int qcrypto_akcipher_max_ciphertext_len(QCryptoAkCipher *akcipher);

int qcrypto_akcipher_max_signature_len(QCryptoAkCipher *akcipher);

int qcrypto_akcipher_max_dgst_len(QCryptoAkCipher *akcipher);

/**
 * qcrypto_akcipher_free:
 * @akcipher: akcipher context
 *
 * Free the akcipher context
 *
 */
void qcrypto_akcipher_free(QCryptoAkCipher *akcipher);

/**
 * qcrypto_akcipher_export_p8info:
 * @opts: the options of the akcipher to be exported.
 * @key: the original key of the akcipher to be exported.
 * @keylen: length of the 'key'
 * @dst: output parameter, if export succeed, *dst is set to the
 * PKCS#8 encoded private key, caller MUST free this key with
 * g_free after use.
 * @dst_len: output parameter, indicates the length of PKCS#8 encoded
 * key.
 *
 * Export the akcipher into DER encoded pkcs#8 private key info, expects
 * |key| stores a valid asymmetric PRIVATE key.
 *
 * Returns: 0 for succeed, otherwise -1 is returned.
 */
int qcrypto_akcipher_export_p8info(const QCryptoAkCipherOptions *opts,
                                   uint8_t *key, size_t keylen,
                                   uint8_t **dst, size_t *dst_len,
                                   Error **errp);

G_DEFINE_AUTOPTR_CLEANUP_FUNC(QCryptoAkCipher, qcrypto_akcipher_free)

#endif /* QCRYPTO_AKCIPHER_H */