pigweed / third_party / github / ARMmbed / mbedtls / c2a938711085813eae11d99550b280c416a8242e / . / library / rsa_alt_helpers.h

/** | |

* \file rsa_alt_helpers.h | |

* | |

* \brief Context-independent RSA helper functions | |

* | |

* This module declares some RSA-related helper functions useful when | |

* implementing the RSA interface. These functions are provided in a separate | |

* compilation unit in order to make it easy for designers of alternative RSA | |

* implementations to use them in their own code, as it is conceived that the | |

* functionality they provide will be necessary for most complete | |

* implementations. | |

* | |

* End-users of Mbed TLS who are not providing their own alternative RSA | |

* implementations should not use these functions directly, and should instead | |

* use only the functions declared in rsa.h. | |

* | |

* The interface provided by this module will be maintained through LTS (Long | |

* Term Support) branches of Mbed TLS, but may otherwise be subject to change, | |

* and must be considered an internal interface of the library. | |

* | |

* There are two classes of helper functions: | |

* | |

* (1) Parameter-generating helpers. These are: | |

* - mbedtls_rsa_deduce_primes | |

* - mbedtls_rsa_deduce_private_exponent | |

* - mbedtls_rsa_deduce_crt | |

* Each of these functions takes a set of core RSA parameters and | |

* generates some other, or CRT related parameters. | |

* | |

* (2) Parameter-checking helpers. These are: | |

* - mbedtls_rsa_validate_params | |

* - mbedtls_rsa_validate_crt | |

* They take a set of core or CRT related RSA parameters and check their | |

* validity. | |

* | |

*/ | |

/* | |

* Copyright The Mbed TLS Contributors | |

* SPDX-License-Identifier: Apache-2.0 | |

* | |

* 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 MBEDTLS_RSA_INTERNAL_H | |

#define MBEDTLS_RSA_INTERNAL_H | |

#include "mbedtls/build_info.h" | |

#include "mbedtls/bignum.h" | |

#ifdef __cplusplus | |

extern "C" { | |

#endif | |

/** | |

* \brief Compute RSA prime moduli P, Q from public modulus N=PQ | |

* and a pair of private and public key. | |

* | |

* \note This is a 'static' helper function not operating on | |

* an RSA context. Alternative implementations need not | |

* overwrite it. | |

* | |

* \param N RSA modulus N = PQ, with P, Q to be found | |

* \param E RSA public exponent | |

* \param D RSA private exponent | |

* \param P Pointer to MPI holding first prime factor of N on success | |

* \param Q Pointer to MPI holding second prime factor of N on success | |

* | |

* \return | |

* - 0 if successful. In this case, P and Q constitute a | |

* factorization of N. | |

* - A non-zero error code otherwise. | |

* | |

* \note It is neither checked that P, Q are prime nor that | |

* D, E are modular inverses wrt. P-1 and Q-1. For that, | |

* use the helper function \c mbedtls_rsa_validate_params. | |

* | |

*/ | |

int mbedtls_rsa_deduce_primes( mbedtls_mpi const *N, mbedtls_mpi const *E, | |

mbedtls_mpi const *D, | |

mbedtls_mpi *P, mbedtls_mpi *Q ); | |

/** | |

* \brief Compute RSA private exponent from | |

* prime moduli and public key. | |

* | |

* \note This is a 'static' helper function not operating on | |

* an RSA context. Alternative implementations need not | |

* overwrite it. | |

* | |

* \param P First prime factor of RSA modulus | |

* \param Q Second prime factor of RSA modulus | |

* \param E RSA public exponent | |

* \param D Pointer to MPI holding the private exponent on success. | |

* | |

* \return | |

* - 0 if successful. In this case, D is set to a simultaneous | |

* modular inverse of E modulo both P-1 and Q-1. | |

* - A non-zero error code otherwise. | |

* | |

* \note This function does not check whether P and Q are primes. | |

* | |

*/ | |

int mbedtls_rsa_deduce_private_exponent( mbedtls_mpi const *P, | |

mbedtls_mpi const *Q, | |

mbedtls_mpi const *E, | |

mbedtls_mpi *D ); | |

/** | |

* \brief Generate RSA-CRT parameters | |

* | |

* \note This is a 'static' helper function not operating on | |

* an RSA context. Alternative implementations need not | |

* overwrite it. | |

* | |

* \param P First prime factor of N | |

* \param Q Second prime factor of N | |

* \param D RSA private exponent | |

* \param DP Output variable for D modulo P-1 | |

* \param DQ Output variable for D modulo Q-1 | |

* \param QP Output variable for the modular inverse of Q modulo P. | |

* | |

* \return 0 on success, non-zero error code otherwise. | |

* | |

* \note This function does not check whether P, Q are | |

* prime and whether D is a valid private exponent. | |

* | |

*/ | |

int mbedtls_rsa_deduce_crt( const mbedtls_mpi *P, const mbedtls_mpi *Q, | |

const mbedtls_mpi *D, mbedtls_mpi *DP, | |

mbedtls_mpi *DQ, mbedtls_mpi *QP ); | |

/** | |

* \brief Check validity of core RSA parameters | |

* | |

* \note This is a 'static' helper function not operating on | |

* an RSA context. Alternative implementations need not | |

* overwrite it. | |

* | |

* \param N RSA modulus N = PQ | |

* \param P First prime factor of N | |

* \param Q Second prime factor of N | |

* \param D RSA private exponent | |

* \param E RSA public exponent | |

* \param f_rng PRNG to be used for primality check, or NULL | |

* \param p_rng PRNG context for f_rng, or NULL | |

* | |

* \return | |

* - 0 if the following conditions are satisfied | |

* if all relevant parameters are provided: | |

* - P prime if f_rng != NULL (%) | |

* - Q prime if f_rng != NULL (%) | |

* - 1 < N = P * Q | |

* - 1 < D, E < N | |

* - D and E are modular inverses modulo P-1 and Q-1 | |

* (%) This is only done if MBEDTLS_GENPRIME is defined. | |

* - A non-zero error code otherwise. | |

* | |

* \note The function can be used with a restricted set of arguments | |

* to perform specific checks only. E.g., calling it with | |

* (-,P,-,-,-) and a PRNG amounts to a primality check for P. | |

*/ | |

int mbedtls_rsa_validate_params( const mbedtls_mpi *N, const mbedtls_mpi *P, | |

const mbedtls_mpi *Q, const mbedtls_mpi *D, | |

const mbedtls_mpi *E, | |

int (*f_rng)(void *, unsigned char *, size_t), | |

void *p_rng ); | |

/** | |

* \brief Check validity of RSA CRT parameters | |

* | |

* \note This is a 'static' helper function not operating on | |

* an RSA context. Alternative implementations need not | |

* overwrite it. | |

* | |

* \param P First prime factor of RSA modulus | |

* \param Q Second prime factor of RSA modulus | |

* \param D RSA private exponent | |

* \param DP MPI to check for D modulo P-1 | |

* \param DQ MPI to check for D modulo P-1 | |

* \param QP MPI to check for the modular inverse of Q modulo P. | |

* | |

* \return | |

* - 0 if the following conditions are satisfied: | |

* - D = DP mod P-1 if P, D, DP != NULL | |

* - Q = DQ mod P-1 if P, D, DQ != NULL | |

* - QP = Q^-1 mod P if P, Q, QP != NULL | |

* - \c MBEDTLS_ERR_RSA_KEY_CHECK_FAILED if check failed, | |

* potentially including \c MBEDTLS_ERR_MPI_XXX if some | |

* MPI calculations failed. | |

* - \c MBEDTLS_ERR_RSA_BAD_INPUT_DATA if insufficient | |

* data was provided to check DP, DQ or QP. | |

* | |

* \note The function can be used with a restricted set of arguments | |

* to perform specific checks only. E.g., calling it with the | |

* parameters (P, -, D, DP, -, -) will check DP = D mod P-1. | |

*/ | |

int mbedtls_rsa_validate_crt( const mbedtls_mpi *P, const mbedtls_mpi *Q, | |

const mbedtls_mpi *D, const mbedtls_mpi *DP, | |

const mbedtls_mpi *DQ, const mbedtls_mpi *QP ); | |

#ifdef __cplusplus | |

} | |

#endif | |

#endif /* rsa_alt_helpers.h */ |