From 626a8d8d3df8880991684d6d1a06b82f6685b51a Mon Sep 17 00:00:00 2001 From: vnugent Date: Sun, 28 Jan 2024 19:23:18 -0500 Subject: initial commit --- include/mbedtls/rsa.h | 1152 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 1152 insertions(+) create mode 100644 include/mbedtls/rsa.h (limited to 'include/mbedtls/rsa.h') diff --git a/include/mbedtls/rsa.h b/include/mbedtls/rsa.h new file mode 100644 index 0000000..be831f1 --- /dev/null +++ b/include/mbedtls/rsa.h @@ -0,0 +1,1152 @@ +/** + * \file rsa.h + * + * \brief This file provides an API for the RSA public-key cryptosystem. + * + * The RSA public-key cryptosystem is defined in Public-Key + * Cryptography Standards (PKCS) #1 v1.5: RSA Encryption + * and Public-Key Cryptography Standards (PKCS) #1 v2.1: + * RSA Cryptography Specifications. + * + */ +/* + * Copyright The Mbed TLS Contributors + * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later + */ +#ifndef MBEDTLS_RSA_H +#define MBEDTLS_RSA_H +#include "mbedtls/private_access.h" + +#include "mbedtls/build_info.h" + +#include "mbedtls/bignum.h" +#include "mbedtls/md.h" + +#if defined(MBEDTLS_THREADING_C) +#include "mbedtls/threading.h" +#endif + +/* + * RSA Error codes + */ +/** Bad input parameters to function. */ +#define MBEDTLS_ERR_RSA_BAD_INPUT_DATA -0x4080 +/** Input data contains invalid padding and is rejected. */ +#define MBEDTLS_ERR_RSA_INVALID_PADDING -0x4100 +/** Something failed during generation of a key. */ +#define MBEDTLS_ERR_RSA_KEY_GEN_FAILED -0x4180 +/** Key failed to pass the validity check of the library. */ +#define MBEDTLS_ERR_RSA_KEY_CHECK_FAILED -0x4200 +/** The public key operation failed. */ +#define MBEDTLS_ERR_RSA_PUBLIC_FAILED -0x4280 +/** The private key operation failed. */ +#define MBEDTLS_ERR_RSA_PRIVATE_FAILED -0x4300 +/** The PKCS#1 verification failed. */ +#define MBEDTLS_ERR_RSA_VERIFY_FAILED -0x4380 +/** The output buffer for decryption is not large enough. */ +#define MBEDTLS_ERR_RSA_OUTPUT_TOO_LARGE -0x4400 +/** The random generator failed to generate non-zeros. */ +#define MBEDTLS_ERR_RSA_RNG_FAILED -0x4480 + +/* + * RSA constants + */ + +#define MBEDTLS_RSA_PKCS_V15 0 /**< Use PKCS#1 v1.5 encoding. */ +#define MBEDTLS_RSA_PKCS_V21 1 /**< Use PKCS#1 v2.1 encoding. */ + +#define MBEDTLS_RSA_SIGN 1 /**< Identifier for RSA signature operations. */ +#define MBEDTLS_RSA_CRYPT 2 /**< Identifier for RSA encryption and decryption operations. */ + +#define MBEDTLS_RSA_SALT_LEN_ANY -1 + +/* + * The above constants may be used even if the RSA module is compile out, + * eg for alternative (PKCS#11) RSA implementations in the PK layers. + */ + +#ifdef __cplusplus +extern "C" { +#endif + +#if !defined(MBEDTLS_RSA_ALT) +// Regular implementation +// + +#if !defined(MBEDTLS_RSA_GEN_KEY_MIN_BITS) +#define MBEDTLS_RSA_GEN_KEY_MIN_BITS 1024 +#elif MBEDTLS_RSA_GEN_KEY_MIN_BITS < 128 +#error "MBEDTLS_RSA_GEN_KEY_MIN_BITS must be at least 128 bits" +#endif + +/** + * \brief The RSA context structure. + */ +typedef struct mbedtls_rsa_context { + int MBEDTLS_PRIVATE(ver); /*!< Reserved for internal purposes. + * Do not set this field in application + * code. Its meaning might change without + * notice. */ + size_t MBEDTLS_PRIVATE(len); /*!< The size of \p N in Bytes. */ + + mbedtls_mpi MBEDTLS_PRIVATE(N); /*!< The public modulus. */ + mbedtls_mpi MBEDTLS_PRIVATE(E); /*!< The public exponent. */ + + mbedtls_mpi MBEDTLS_PRIVATE(D); /*!< The private exponent. */ + mbedtls_mpi MBEDTLS_PRIVATE(P); /*!< The first prime factor. */ + mbedtls_mpi MBEDTLS_PRIVATE(Q); /*!< The second prime factor. */ + + mbedtls_mpi MBEDTLS_PRIVATE(DP); /*!< D % (P - 1). */ + mbedtls_mpi MBEDTLS_PRIVATE(DQ); /*!< D % (Q - 1). */ + mbedtls_mpi MBEDTLS_PRIVATE(QP); /*!< 1 / (Q % P). */ + + mbedtls_mpi MBEDTLS_PRIVATE(RN); /*!< cached R^2 mod N. */ + + mbedtls_mpi MBEDTLS_PRIVATE(RP); /*!< cached R^2 mod P. */ + mbedtls_mpi MBEDTLS_PRIVATE(RQ); /*!< cached R^2 mod Q. */ + + mbedtls_mpi MBEDTLS_PRIVATE(Vi); /*!< The cached blinding value. */ + mbedtls_mpi MBEDTLS_PRIVATE(Vf); /*!< The cached un-blinding value. */ + + int MBEDTLS_PRIVATE(padding); /*!< Selects padding mode: + #MBEDTLS_RSA_PKCS_V15 for 1.5 padding and + #MBEDTLS_RSA_PKCS_V21 for OAEP or PSS. */ + int MBEDTLS_PRIVATE(hash_id); /*!< Hash identifier of mbedtls_md_type_t type, + as specified in md.h for use in the MGF + mask generating function used in the + EME-OAEP and EMSA-PSS encodings. */ +#if defined(MBEDTLS_THREADING_C) + /* Invariant: the mutex is initialized iff ver != 0. */ + mbedtls_threading_mutex_t MBEDTLS_PRIVATE(mutex); /*!< Thread-safety mutex. */ +#endif +} +mbedtls_rsa_context; + +#else /* MBEDTLS_RSA_ALT */ +#include "rsa_alt.h" +#endif /* MBEDTLS_RSA_ALT */ + +/** + * \brief This function initializes an RSA context. + * + * \note This function initializes the padding and the hash + * identifier to respectively #MBEDTLS_RSA_PKCS_V15 and + * #MBEDTLS_MD_NONE. See mbedtls_rsa_set_padding() for more + * information about those parameters. + * + * \param ctx The RSA context to initialize. This must not be \c NULL. + */ +void mbedtls_rsa_init(mbedtls_rsa_context *ctx); + +/** + * \brief This function sets padding for an already initialized RSA + * context. + * + * \note Set padding to #MBEDTLS_RSA_PKCS_V21 for the RSAES-OAEP + * encryption scheme and the RSASSA-PSS signature scheme. + * + * \note The \p hash_id parameter is ignored when using + * #MBEDTLS_RSA_PKCS_V15 padding. + * + * \note The choice of padding mode is strictly enforced for private + * key operations, since there might be security concerns in + * mixing padding modes. For public key operations it is + * a default value, which can be overridden by calling specific + * \c mbedtls_rsa_rsaes_xxx or \c mbedtls_rsa_rsassa_xxx + * functions. + * + * \note The hash selected in \p hash_id is always used for OEAP + * encryption. For PSS signatures, it is always used for + * making signatures, but can be overridden for verifying them. + * If set to #MBEDTLS_MD_NONE, it is always overridden. + * + * \param ctx The initialized RSA context to be configured. + * \param padding The padding mode to use. This must be either + * #MBEDTLS_RSA_PKCS_V15 or #MBEDTLS_RSA_PKCS_V21. + * \param hash_id The hash identifier for PSS or OAEP, if \p padding is + * #MBEDTLS_RSA_PKCS_V21. #MBEDTLS_MD_NONE is accepted by this + * function but may be not suitable for some operations. + * Ignored if \p padding is #MBEDTLS_RSA_PKCS_V15. + * + * \return \c 0 on success. + * \return #MBEDTLS_ERR_RSA_INVALID_PADDING failure: + * \p padding or \p hash_id is invalid. + */ +int mbedtls_rsa_set_padding(mbedtls_rsa_context *ctx, int padding, + mbedtls_md_type_t hash_id); + +/** + * \brief This function retrieves padding mode of initialized + * RSA context. + * + * \param ctx The initialized RSA context. + * + * \return RSA padding mode. + * + */ +int mbedtls_rsa_get_padding_mode(const mbedtls_rsa_context *ctx); + +/** + * \brief This function retrieves hash identifier of mbedtls_md_type_t + * type. + * + * \param ctx The initialized RSA context. + * + * \return Hash identifier of mbedtls_md_type_t type. + * + */ +int mbedtls_rsa_get_md_alg(const mbedtls_rsa_context *ctx); + +/** + * \brief This function imports a set of core parameters into an + * RSA context. + * + * \note This function can be called multiple times for successive + * imports, if the parameters are not simultaneously present. + * + * Any sequence of calls to this function should be followed + * by a call to mbedtls_rsa_complete(), which checks and + * completes the provided information to a ready-for-use + * public or private RSA key. + * + * \note See mbedtls_rsa_complete() for more information on which + * parameters are necessary to set up a private or public + * RSA key. + * + * \note The imported parameters are copied and need not be preserved + * for the lifetime of the RSA context being set up. + * + * \param ctx The initialized RSA context to store the parameters in. + * \param N The RSA modulus. This may be \c NULL. + * \param P The first prime factor of \p N. This may be \c NULL. + * \param Q The second prime factor of \p N. This may be \c NULL. + * \param D The private exponent. This may be \c NULL. + * \param E The public exponent. This may be \c NULL. + * + * \return \c 0 on success. + * \return A non-zero error code on failure. + */ +int mbedtls_rsa_import(mbedtls_rsa_context *ctx, + const mbedtls_mpi *N, + const mbedtls_mpi *P, const mbedtls_mpi *Q, + const mbedtls_mpi *D, const mbedtls_mpi *E); + +/** + * \brief This function imports core RSA parameters, in raw big-endian + * binary format, into an RSA context. + * + * \note This function can be called multiple times for successive + * imports, if the parameters are not simultaneously present. + * + * Any sequence of calls to this function should be followed + * by a call to mbedtls_rsa_complete(), which checks and + * completes the provided information to a ready-for-use + * public or private RSA key. + * + * \note See mbedtls_rsa_complete() for more information on which + * parameters are necessary to set up a private or public + * RSA key. + * + * \note The imported parameters are copied and need not be preserved + * for the lifetime of the RSA context being set up. + * + * \param ctx The initialized RSA context to store the parameters in. + * \param N The RSA modulus. This may be \c NULL. + * \param N_len The Byte length of \p N; it is ignored if \p N == NULL. + * \param P The first prime factor of \p N. This may be \c NULL. + * \param P_len The Byte length of \p P; it is ignored if \p P == NULL. + * \param Q The second prime factor of \p N. This may be \c NULL. + * \param Q_len The Byte length of \p Q; it is ignored if \p Q == NULL. + * \param D The private exponent. This may be \c NULL. + * \param D_len The Byte length of \p D; it is ignored if \p D == NULL. + * \param E The public exponent. This may be \c NULL. + * \param E_len The Byte length of \p E; it is ignored if \p E == NULL. + * + * \return \c 0 on success. + * \return A non-zero error code on failure. + */ +int mbedtls_rsa_import_raw(mbedtls_rsa_context *ctx, + unsigned char const *N, size_t N_len, + unsigned char const *P, size_t P_len, + unsigned char const *Q, size_t Q_len, + unsigned char const *D, size_t D_len, + unsigned char const *E, size_t E_len); + +/** + * \brief This function completes an RSA context from + * a set of imported core parameters. + * + * To setup an RSA public key, precisely \c N and \c E + * must have been imported. + * + * To setup an RSA private key, sufficient information must + * be present for the other parameters to be derivable. + * + * The default implementation supports the following: + * + * Alternative implementations need not support these. + * + * If this function runs successfully, it guarantees that + * the RSA context can be used for RSA operations without + * the risk of failure or crash. + * + * \warning This function need not perform consistency checks + * for the imported parameters. In particular, parameters that + * are not needed by the implementation might be silently + * discarded and left unchecked. To check the consistency + * of the key material, see mbedtls_rsa_check_privkey(). + * + * \param ctx The initialized RSA context holding imported parameters. + * + * \return \c 0 on success. + * \return #MBEDTLS_ERR_RSA_BAD_INPUT_DATA if the attempted derivations + * failed. + * + */ +int mbedtls_rsa_complete(mbedtls_rsa_context *ctx); + +/** + * \brief This function exports the core parameters of an RSA key. + * + * If this function runs successfully, the non-NULL buffers + * pointed to by \p N, \p P, \p Q, \p D, and \p E are fully + * written, with additional unused space filled leading by + * zero Bytes. + * + * Possible reasons for returning + * #MBEDTLS_ERR_PLATFORM_FEATURE_UNSUPPORTED: + * + * If the function fails due to an unsupported operation, + * the RSA context stays intact and remains usable. + * + * \param ctx The initialized RSA context. + * \param N The MPI to hold the RSA modulus. + * This may be \c NULL if this field need not be exported. + * \param P The MPI to hold the first prime factor of \p N. + * This may be \c NULL if this field need not be exported. + * \param Q The MPI to hold the second prime factor of \p N. + * This may be \c NULL if this field need not be exported. + * \param D The MPI to hold the private exponent. + * This may be \c NULL if this field need not be exported. + * \param E The MPI to hold the public exponent. + * This may be \c NULL if this field need not be exported. + * + * \return \c 0 on success. + * \return #MBEDTLS_ERR_PLATFORM_FEATURE_UNSUPPORTED if exporting the + * requested parameters cannot be done due to missing + * functionality or because of security policies. + * \return A non-zero return code on any other failure. + * + */ +int mbedtls_rsa_export(const mbedtls_rsa_context *ctx, + mbedtls_mpi *N, mbedtls_mpi *P, mbedtls_mpi *Q, + mbedtls_mpi *D, mbedtls_mpi *E); + +/** + * \brief This function exports core parameters of an RSA key + * in raw big-endian binary format. + * + * If this function runs successfully, the non-NULL buffers + * pointed to by \p N, \p P, \p Q, \p D, and \p E are fully + * written, with additional unused space filled leading by + * zero Bytes. + * + * Possible reasons for returning + * #MBEDTLS_ERR_PLATFORM_FEATURE_UNSUPPORTED: + * If the function fails due to an unsupported operation, + * the RSA context stays intact and remains usable. + * + * \note The length parameters are ignored if the corresponding + * buffer pointers are NULL. + * + * \param ctx The initialized RSA context. + * \param N The Byte array to store the RSA modulus, + * or \c NULL if this field need not be exported. + * \param N_len The size of the buffer for the modulus. + * \param P The Byte array to hold the first prime factor of \p N, + * or \c NULL if this field need not be exported. + * \param P_len The size of the buffer for the first prime factor. + * \param Q The Byte array to hold the second prime factor of \p N, + * or \c NULL if this field need not be exported. + * \param Q_len The size of the buffer for the second prime factor. + * \param D The Byte array to hold the private exponent, + * or \c NULL if this field need not be exported. + * \param D_len The size of the buffer for the private exponent. + * \param E The Byte array to hold the public exponent, + * or \c NULL if this field need not be exported. + * \param E_len The size of the buffer for the public exponent. + * + * \return \c 0 on success. + * \return #MBEDTLS_ERR_PLATFORM_FEATURE_UNSUPPORTED if exporting the + * requested parameters cannot be done due to missing + * functionality or because of security policies. + * \return A non-zero return code on any other failure. + */ +int mbedtls_rsa_export_raw(const mbedtls_rsa_context *ctx, + unsigned char *N, size_t N_len, + unsigned char *P, size_t P_len, + unsigned char *Q, size_t Q_len, + unsigned char *D, size_t D_len, + unsigned char *E, size_t E_len); + +/** + * \brief This function exports CRT parameters of a private RSA key. + * + * \note Alternative RSA implementations not using CRT-parameters + * internally can implement this function based on + * mbedtls_rsa_deduce_opt(). + * + * \param ctx The initialized RSA context. + * \param DP The MPI to hold \c D modulo `P-1`, + * or \c NULL if it need not be exported. + * \param DQ The MPI to hold \c D modulo `Q-1`, + * or \c NULL if it need not be exported. + * \param QP The MPI to hold modular inverse of \c Q modulo \c P, + * or \c NULL if it need not be exported. + * + * \return \c 0 on success. + * \return A non-zero error code on failure. + * + */ +int mbedtls_rsa_export_crt(const mbedtls_rsa_context *ctx, + mbedtls_mpi *DP, mbedtls_mpi *DQ, mbedtls_mpi *QP); + +/** + * \brief This function retrieves the length of RSA modulus in Bytes. + * + * \param ctx The initialized RSA context. + * + * \return The length of the RSA modulus in Bytes. + * + */ +size_t mbedtls_rsa_get_len(const mbedtls_rsa_context *ctx); + +/** + * \brief This function generates an RSA keypair. + * + * \note mbedtls_rsa_init() must be called before this function, + * to set up the RSA context. + * + * \param ctx The initialized RSA context used to hold the key. + * \param f_rng The RNG function to be used for key generation. + * This is mandatory and must not be \c NULL. + * \param p_rng The RNG context to be passed to \p f_rng. + * This may be \c NULL if \p f_rng doesn't need a context. + * \param nbits The size of the public key in bits. + * \param exponent The public exponent to use. For example, \c 65537. + * This must be odd and greater than \c 1. + * + * \return \c 0 on success. + * \return An \c MBEDTLS_ERR_RSA_XXX error code on failure. + */ +int mbedtls_rsa_gen_key(mbedtls_rsa_context *ctx, + int (*f_rng)(void *, unsigned char *, size_t), + void *p_rng, + unsigned int nbits, int exponent); + +/** + * \brief This function checks if a context contains at least an RSA + * public key. + * + * If the function runs successfully, it is guaranteed that + * enough information is present to perform an RSA public key + * operation using mbedtls_rsa_public(). + * + * \param ctx The initialized RSA context to check. + * + * \return \c 0 on success. + * \return An \c MBEDTLS_ERR_RSA_XXX error code on failure. + * + */ +int mbedtls_rsa_check_pubkey(const mbedtls_rsa_context *ctx); + +/** + * \brief This function checks if a context contains an RSA private key + * and perform basic consistency checks. + * + * \note The consistency checks performed by this function not only + * ensure that mbedtls_rsa_private() can be called successfully + * on the given context, but that the various parameters are + * mutually consistent with high probability, in the sense that + * mbedtls_rsa_public() and mbedtls_rsa_private() are inverses. + * + * \warning This function should catch accidental misconfigurations + * like swapping of parameters, but it cannot establish full + * trust in neither the quality nor the consistency of the key + * material that was used to setup the given RSA context: + * + * + * \param ctx The initialized RSA context to check. + * + * \return \c 0 on success. + * \return An \c MBEDTLS_ERR_RSA_XXX error code on failure. + */ +int mbedtls_rsa_check_privkey(const mbedtls_rsa_context *ctx); + +/** + * \brief This function checks a public-private RSA key pair. + * + * It checks each of the contexts, and makes sure they match. + * + * \param pub The initialized RSA context holding the public key. + * \param prv The initialized RSA context holding the private key. + * + * \return \c 0 on success. + * \return An \c MBEDTLS_ERR_RSA_XXX error code on failure. + */ +int mbedtls_rsa_check_pub_priv(const mbedtls_rsa_context *pub, + const mbedtls_rsa_context *prv); + +/** + * \brief This function performs an RSA public key operation. + * + * \param ctx The initialized RSA context to use. + * \param input The input buffer. This must be a readable buffer + * of length \c ctx->len Bytes. For example, \c 256 Bytes + * for an 2048-bit RSA modulus. + * \param output The output buffer. This must be a writable buffer + * of length \c ctx->len Bytes. For example, \c 256 Bytes + * for an 2048-bit RSA modulus. + * + * \note This function does not handle message padding. + * + * \note Make sure to set \p input[0] = 0 or ensure that + * input is smaller than \c N. + * + * \return \c 0 on success. + * \return An \c MBEDTLS_ERR_RSA_XXX error code on failure. + */ +int mbedtls_rsa_public(mbedtls_rsa_context *ctx, + const unsigned char *input, + unsigned char *output); + +/** + * \brief This function performs an RSA private key operation. + * + * \note Blinding is used if and only if a PRNG is provided. + * + * \note If blinding is used, both the base of exponentiation + * and the exponent are blinded, providing protection + * against some side-channel attacks. + * + * \warning It is deprecated and a security risk to not provide + * a PRNG here and thereby prevent the use of blinding. + * Future versions of the library may enforce the presence + * of a PRNG. + * + * \param ctx The initialized RSA context to use. + * \param f_rng The RNG function, used for blinding. It is mandatory. + * \param p_rng The RNG context to pass to \p f_rng. This may be \c NULL + * if \p f_rng doesn't need a context. + * \param input The input buffer. This must be a readable buffer + * of length \c ctx->len Bytes. For example, \c 256 Bytes + * for an 2048-bit RSA modulus. + * \param output The output buffer. This must be a writable buffer + * of length \c ctx->len Bytes. For example, \c 256 Bytes + * for an 2048-bit RSA modulus. + * + * \return \c 0 on success. + * \return An \c MBEDTLS_ERR_RSA_XXX error code on failure. + * + */ +int mbedtls_rsa_private(mbedtls_rsa_context *ctx, + int (*f_rng)(void *, unsigned char *, size_t), + void *p_rng, + const unsigned char *input, + unsigned char *output); + +/** + * \brief This function adds the message padding, then performs an RSA + * operation. + * + * It is the generic wrapper for performing a PKCS#1 encryption + * operation. + * + * \param ctx The initialized RSA context to use. + * \param f_rng The RNG to use. It is used for padding generation + * and it is mandatory. + * \param p_rng The RNG context to be passed to \p f_rng. May be + * \c NULL if \p f_rng doesn't need a context argument. + * \param ilen The length of the plaintext in Bytes. + * \param input The input data to encrypt. This must be a readable + * buffer of size \p ilen Bytes. It may be \c NULL if + * `ilen == 0`. + * \param output The output buffer. This must be a writable buffer + * of length \c ctx->len Bytes. For example, \c 256 Bytes + * for an 2048-bit RSA modulus. + * + * \return \c 0 on success. + * \return An \c MBEDTLS_ERR_RSA_XXX error code on failure. + */ +int mbedtls_rsa_pkcs1_encrypt(mbedtls_rsa_context *ctx, + int (*f_rng)(void *, unsigned char *, size_t), + void *p_rng, + size_t ilen, + const unsigned char *input, + unsigned char *output); + +/** + * \brief This function performs a PKCS#1 v1.5 encryption operation + * (RSAES-PKCS1-v1_5-ENCRYPT). + * + * \param ctx The initialized RSA context to use. + * \param f_rng The RNG function to use. It is mandatory and used for + * padding generation. + * \param p_rng The RNG context to be passed to \p f_rng. This may + * be \c NULL if \p f_rng doesn't need a context argument. + * \param ilen The length of the plaintext in Bytes. + * \param input The input data to encrypt. This must be a readable + * buffer of size \p ilen Bytes. It may be \c NULL if + * `ilen == 0`. + * \param output The output buffer. This must be a writable buffer + * of length \c ctx->len Bytes. For example, \c 256 Bytes + * for an 2048-bit RSA modulus. + * + * \return \c 0 on success. + * \return An \c MBEDTLS_ERR_RSA_XXX error code on failure. + */ +int mbedtls_rsa_rsaes_pkcs1_v15_encrypt(mbedtls_rsa_context *ctx, + int (*f_rng)(void *, unsigned char *, size_t), + void *p_rng, + size_t ilen, + const unsigned char *input, + unsigned char *output); + +/** + * \brief This function performs a PKCS#1 v2.1 OAEP encryption + * operation (RSAES-OAEP-ENCRYPT). + * + * \note The output buffer must be as large as the size + * of ctx->N. For example, 128 Bytes if RSA-1024 is used. + * + * \param ctx The initialized RSA context to use. + * \param f_rng The RNG function to use. This is needed for padding + * generation and is mandatory. + * \param p_rng The RNG context to be passed to \p f_rng. This may + * be \c NULL if \p f_rng doesn't need a context argument. + * \param label The buffer holding the custom label to use. + * This must be a readable buffer of length \p label_len + * Bytes. It may be \c NULL if \p label_len is \c 0. + * \param label_len The length of the label in Bytes. + * \param ilen The length of the plaintext buffer \p input in Bytes. + * \param input The input data to encrypt. This must be a readable + * buffer of size \p ilen Bytes. It may be \c NULL if + * `ilen == 0`. + * \param output The output buffer. This must be a writable buffer + * of length \c ctx->len Bytes. For example, \c 256 Bytes + * for an 2048-bit RSA modulus. + * + * \return \c 0 on success. + * \return An \c MBEDTLS_ERR_RSA_XXX error code on failure. + */ +int mbedtls_rsa_rsaes_oaep_encrypt(mbedtls_rsa_context *ctx, + int (*f_rng)(void *, unsigned char *, size_t), + void *p_rng, + const unsigned char *label, size_t label_len, + size_t ilen, + const unsigned char *input, + unsigned char *output); + +/** + * \brief This function performs an RSA operation, then removes the + * message padding. + * + * It is the generic wrapper for performing a PKCS#1 decryption + * operation. + * + * \warning When \p ctx->padding is set to #MBEDTLS_RSA_PKCS_V15, + * mbedtls_rsa_rsaes_pkcs1_v15_decrypt() is called, which is an + * inherently dangerous function (CWE-242). + * + * \note The output buffer length \c output_max_len should be + * as large as the size \p ctx->len of \p ctx->N (for example, + * 128 Bytes if RSA-1024 is used) to be able to hold an + * arbitrary decrypted message. If it is not large enough to + * hold the decryption of the particular ciphertext provided, + * the function returns \c MBEDTLS_ERR_RSA_OUTPUT_TOO_LARGE. + * + * \param ctx The initialized RSA context to use. + * \param f_rng The RNG function. This is used for blinding and is + * mandatory; see mbedtls_rsa_private() for more. + * \param p_rng The RNG context to be passed to \p f_rng. This may be + * \c NULL if \p f_rng doesn't need a context. + * \param olen The address at which to store the length of + * the plaintext. This must not be \c NULL. + * \param input The ciphertext buffer. This must be a readable buffer + * of length \c ctx->len Bytes. For example, \c 256 Bytes + * for an 2048-bit RSA modulus. + * \param output The buffer used to hold the plaintext. This must + * be a writable buffer of length \p output_max_len Bytes. + * \param output_max_len The length in Bytes of the output buffer \p output. + * + * \return \c 0 on success. + * \return An \c MBEDTLS_ERR_RSA_XXX error code on failure. + */ +int mbedtls_rsa_pkcs1_decrypt(mbedtls_rsa_context *ctx, + int (*f_rng)(void *, unsigned char *, size_t), + void *p_rng, + size_t *olen, + const unsigned char *input, + unsigned char *output, + size_t output_max_len); + +/** + * \brief This function performs a PKCS#1 v1.5 decryption + * operation (RSAES-PKCS1-v1_5-DECRYPT). + * + * \warning This is an inherently dangerous function (CWE-242). Unless + * it is used in a side channel free and safe way (eg. + * implementing the TLS protocol as per 7.4.7.1 of RFC 5246), + * the calling code is vulnerable. + * + * \note The output buffer length \c output_max_len should be + * as large as the size \p ctx->len of \p ctx->N, for example, + * 128 Bytes if RSA-1024 is used, to be able to hold an + * arbitrary decrypted message. If it is not large enough to + * hold the decryption of the particular ciphertext provided, + * the function returns #MBEDTLS_ERR_RSA_OUTPUT_TOO_LARGE. + * + * \param ctx The initialized RSA context to use. + * \param f_rng The RNG function. This is used for blinding and is + * mandatory; see mbedtls_rsa_private() for more. + * \param p_rng The RNG context to be passed to \p f_rng. This may be + * \c NULL if \p f_rng doesn't need a context. + * \param olen The address at which to store the length of + * the plaintext. This must not be \c NULL. + * \param input The ciphertext buffer. This must be a readable buffer + * of length \c ctx->len Bytes. For example, \c 256 Bytes + * for an 2048-bit RSA modulus. + * \param output The buffer used to hold the plaintext. This must + * be a writable buffer of length \p output_max_len Bytes. + * \param output_max_len The length in Bytes of the output buffer \p output. + * + * \return \c 0 on success. + * \return An \c MBEDTLS_ERR_RSA_XXX error code on failure. + * + */ +int mbedtls_rsa_rsaes_pkcs1_v15_decrypt(mbedtls_rsa_context *ctx, + int (*f_rng)(void *, unsigned char *, size_t), + void *p_rng, + size_t *olen, + const unsigned char *input, + unsigned char *output, + size_t output_max_len); + +/** + * \brief This function performs a PKCS#1 v2.1 OAEP decryption + * operation (RSAES-OAEP-DECRYPT). + * + * \note The output buffer length \c output_max_len should be + * as large as the size \p ctx->len of \p ctx->N, for + * example, 128 Bytes if RSA-1024 is used, to be able to + * hold an arbitrary decrypted message. If it is not + * large enough to hold the decryption of the particular + * ciphertext provided, the function returns + * #MBEDTLS_ERR_RSA_OUTPUT_TOO_LARGE. + * + * \param ctx The initialized RSA context to use. + * \param f_rng The RNG function. This is used for blinding and is + * mandatory. + * \param p_rng The RNG context to be passed to \p f_rng. This may be + * \c NULL if \p f_rng doesn't need a context. + * \param label The buffer holding the custom label to use. + * This must be a readable buffer of length \p label_len + * Bytes. It may be \c NULL if \p label_len is \c 0. + * \param label_len The length of the label in Bytes. + * \param olen The address at which to store the length of + * the plaintext. This must not be \c NULL. + * \param input The ciphertext buffer. This must be a readable buffer + * of length \c ctx->len Bytes. For example, \c 256 Bytes + * for an 2048-bit RSA modulus. + * \param output The buffer used to hold the plaintext. This must + * be a writable buffer of length \p output_max_len Bytes. + * \param output_max_len The length in Bytes of the output buffer \p output. + * + * \return \c 0 on success. + * \return An \c MBEDTLS_ERR_RSA_XXX error code on failure. + */ +int mbedtls_rsa_rsaes_oaep_decrypt(mbedtls_rsa_context *ctx, + int (*f_rng)(void *, unsigned char *, size_t), + void *p_rng, + const unsigned char *label, size_t label_len, + size_t *olen, + const unsigned char *input, + unsigned char *output, + size_t output_max_len); + +/** + * \brief This function performs a private RSA operation to sign + * a message digest using PKCS#1. + * + * It is the generic wrapper for performing a PKCS#1 + * signature. + * + * \note The \p sig buffer must be as large as the size + * of \p ctx->N. For example, 128 Bytes if RSA-1024 is used. + * + * \note For PKCS#1 v2.1 encoding, see comments on + * mbedtls_rsa_rsassa_pss_sign() for details on + * \p md_alg and \p hash_id. + * + * \param ctx The initialized RSA context to use. + * \param f_rng The RNG function to use. This is mandatory and + * must not be \c NULL. + * \param p_rng The RNG context to be passed to \p f_rng. This may be \c NULL + * if \p f_rng doesn't need a context argument. + * \param md_alg The message-digest algorithm used to hash the original data. + * Use #MBEDTLS_MD_NONE for signing raw data. + * \param hashlen The length of the message digest or raw data in Bytes. + * If \p md_alg is not #MBEDTLS_MD_NONE, this must match the + * output length of the corresponding hash algorithm. + * \param hash The buffer holding the message digest or raw data. + * This must be a readable buffer of at least \p hashlen Bytes. + * \param sig The buffer to hold the signature. This must be a writable + * buffer of length \c ctx->len Bytes. For example, \c 256 Bytes + * for an 2048-bit RSA modulus. A buffer length of + * #MBEDTLS_MPI_MAX_SIZE is always safe. + * + * \return \c 0 if the signing operation was successful. + * \return An \c MBEDTLS_ERR_RSA_XXX error code on failure. + */ +int mbedtls_rsa_pkcs1_sign(mbedtls_rsa_context *ctx, + int (*f_rng)(void *, unsigned char *, size_t), + void *p_rng, + mbedtls_md_type_t md_alg, + unsigned int hashlen, + const unsigned char *hash, + unsigned char *sig); + +/** + * \brief This function performs a PKCS#1 v1.5 signature + * operation (RSASSA-PKCS1-v1_5-SIGN). + * + * \param ctx The initialized RSA context to use. + * \param f_rng The RNG function. This is used for blinding and is + * mandatory; see mbedtls_rsa_private() for more. + * \param p_rng The RNG context to be passed to \p f_rng. This may be \c NULL + * if \p f_rng doesn't need a context argument. + * \param md_alg The message-digest algorithm used to hash the original data. + * Use #MBEDTLS_MD_NONE for signing raw data. + * \param hashlen The length of the message digest or raw data in Bytes. + * If \p md_alg is not #MBEDTLS_MD_NONE, this must match the + * output length of the corresponding hash algorithm. + * \param hash The buffer holding the message digest or raw data. + * This must be a readable buffer of at least \p hashlen Bytes. + * \param sig The buffer to hold the signature. This must be a writable + * buffer of length \c ctx->len Bytes. For example, \c 256 Bytes + * for an 2048-bit RSA modulus. A buffer length of + * #MBEDTLS_MPI_MAX_SIZE is always safe. + * + * \return \c 0 if the signing operation was successful. + * \return An \c MBEDTLS_ERR_RSA_XXX error code on failure. + */ +int mbedtls_rsa_rsassa_pkcs1_v15_sign(mbedtls_rsa_context *ctx, + int (*f_rng)(void *, unsigned char *, size_t), + void *p_rng, + mbedtls_md_type_t md_alg, + unsigned int hashlen, + const unsigned char *hash, + unsigned char *sig); + +/** + * \brief This function performs a PKCS#1 v2.1 PSS signature + * operation (RSASSA-PSS-SIGN). + * + * \note The \c hash_id set in \p ctx by calling + * mbedtls_rsa_set_padding() selects the hash used for the + * encoding operation and for the mask generation function + * (MGF1). For more details on the encoding operation and the + * mask generation function, consult RFC-3447: Public-Key + * Cryptography Standards (PKCS) #1 v2.1: RSA Cryptography + * Specifications. + * + * \note This function enforces that the provided salt length complies + * with FIPS 186-4 §5.5 (e) and RFC 8017 (PKCS#1 v2.2) §9.1.1 + * step 3. The constraint is that the hash length plus the salt + * length plus 2 bytes must be at most the key length. If this + * constraint is not met, this function returns + * #MBEDTLS_ERR_RSA_BAD_INPUT_DATA. + * + * \param ctx The initialized RSA context to use. + * \param f_rng The RNG function. It is mandatory and must not be \c NULL. + * \param p_rng The RNG context to be passed to \p f_rng. This may be \c NULL + * if \p f_rng doesn't need a context argument. + * \param md_alg The message-digest algorithm used to hash the original data. + * Use #MBEDTLS_MD_NONE for signing raw data. + * \param hashlen The length of the message digest or raw data in Bytes. + * If \p md_alg is not #MBEDTLS_MD_NONE, this must match the + * output length of the corresponding hash algorithm. + * \param hash The buffer holding the message digest or raw data. + * This must be a readable buffer of at least \p hashlen Bytes. + * \param saltlen The length of the salt that should be used. + * If passed #MBEDTLS_RSA_SALT_LEN_ANY, the function will use + * the largest possible salt length up to the hash length, + * which is the largest permitted by some standards including + * FIPS 186-4 §5.5. + * \param sig The buffer to hold the signature. This must be a writable + * buffer of length \c ctx->len Bytes. For example, \c 256 Bytes + * for an 2048-bit RSA modulus. A buffer length of + * #MBEDTLS_MPI_MAX_SIZE is always safe. + * + * \return \c 0 if the signing operation was successful. + * \return An \c MBEDTLS_ERR_RSA_XXX error code on failure. + */ +int mbedtls_rsa_rsassa_pss_sign_ext(mbedtls_rsa_context *ctx, + int (*f_rng)(void *, unsigned char *, size_t), + void *p_rng, + mbedtls_md_type_t md_alg, + unsigned int hashlen, + const unsigned char *hash, + int saltlen, + unsigned char *sig); + +/** + * \brief This function performs a PKCS#1 v2.1 PSS signature + * operation (RSASSA-PSS-SIGN). + * + * \note The \c hash_id set in \p ctx by calling + * mbedtls_rsa_set_padding() selects the hash used for the + * encoding operation and for the mask generation function + * (MGF1). For more details on the encoding operation and the + * mask generation function, consult RFC-3447: Public-Key + * Cryptography Standards (PKCS) #1 v2.1: RSA Cryptography + * Specifications. + * + * \note This function always uses the maximum possible salt size, + * up to the length of the payload hash. This choice of salt + * size complies with FIPS 186-4 §5.5 (e) and RFC 8017 (PKCS#1 + * v2.2) §9.1.1 step 3. Furthermore this function enforces a + * minimum salt size which is the hash size minus 2 bytes. If + * this minimum size is too large given the key size (the salt + * size, plus the hash size, plus 2 bytes must be no more than + * the key size in bytes), this function returns + * #MBEDTLS_ERR_RSA_BAD_INPUT_DATA. + * + * \param ctx The initialized RSA context to use. + * \param f_rng The RNG function. It is mandatory and must not be \c NULL. + * \param p_rng The RNG context to be passed to \p f_rng. This may be \c NULL + * if \p f_rng doesn't need a context argument. + * \param md_alg The message-digest algorithm used to hash the original data. + * Use #MBEDTLS_MD_NONE for signing raw data. + * \param hashlen The length of the message digest or raw data in Bytes. + * If \p md_alg is not #MBEDTLS_MD_NONE, this must match the + * output length of the corresponding hash algorithm. + * \param hash The buffer holding the message digest or raw data. + * This must be a readable buffer of at least \p hashlen Bytes. + * \param sig The buffer to hold the signature. This must be a writable + * buffer of length \c ctx->len Bytes. For example, \c 256 Bytes + * for an 2048-bit RSA modulus. A buffer length of + * #MBEDTLS_MPI_MAX_SIZE is always safe. + * + * \return \c 0 if the signing operation was successful. + * \return An \c MBEDTLS_ERR_RSA_XXX error code on failure. + */ +int mbedtls_rsa_rsassa_pss_sign(mbedtls_rsa_context *ctx, + int (*f_rng)(void *, unsigned char *, size_t), + void *p_rng, + mbedtls_md_type_t md_alg, + unsigned int hashlen, + const unsigned char *hash, + unsigned char *sig); + +/** + * \brief This function performs a public RSA operation and checks + * the message digest. + * + * This is the generic wrapper for performing a PKCS#1 + * verification. + * + * \note For PKCS#1 v2.1 encoding, see comments on + * mbedtls_rsa_rsassa_pss_verify() about \c md_alg and + * \c hash_id. + * + * \param ctx The initialized RSA public key context to use. + * \param md_alg The message-digest algorithm used to hash the original data. + * Use #MBEDTLS_MD_NONE for signing raw data. + * \param hashlen The length of the message digest or raw data in Bytes. + * If \p md_alg is not #MBEDTLS_MD_NONE, this must match the + * output length of the corresponding hash algorithm. + * \param hash The buffer holding the message digest or raw data. + * This must be a readable buffer of at least \p hashlen Bytes. + * \param sig The buffer holding the signature. This must be a readable + * buffer of length \c ctx->len Bytes. For example, \c 256 Bytes + * for an 2048-bit RSA modulus. + * + * \return \c 0 if the verify operation was successful. + * \return An \c MBEDTLS_ERR_RSA_XXX error code on failure. + */ +int mbedtls_rsa_pkcs1_verify(mbedtls_rsa_context *ctx, + mbedtls_md_type_t md_alg, + unsigned int hashlen, + const unsigned char *hash, + const unsigned char *sig); + +/** + * \brief This function performs a PKCS#1 v1.5 verification + * operation (RSASSA-PKCS1-v1_5-VERIFY). + * + * \param ctx The initialized RSA public key context to use. + * \param md_alg The message-digest algorithm used to hash the original data. + * Use #MBEDTLS_MD_NONE for signing raw data. + * \param hashlen The length of the message digest or raw data in Bytes. + * If \p md_alg is not #MBEDTLS_MD_NONE, this must match the + * output length of the corresponding hash algorithm. + * \param hash The buffer holding the message digest or raw data. + * This must be a readable buffer of at least \p hashlen Bytes. + * \param sig The buffer holding the signature. This must be a readable + * buffer of length \c ctx->len Bytes. For example, \c 256 Bytes + * for an 2048-bit RSA modulus. + * + * \return \c 0 if the verify operation was successful. + * \return An \c MBEDTLS_ERR_RSA_XXX error code on failure. + */ +int mbedtls_rsa_rsassa_pkcs1_v15_verify(mbedtls_rsa_context *ctx, + mbedtls_md_type_t md_alg, + unsigned int hashlen, + const unsigned char *hash, + const unsigned char *sig); + +/** + * \brief This function performs a PKCS#1 v2.1 PSS verification + * operation (RSASSA-PSS-VERIFY). + * + * \note The \c hash_id set in \p ctx by calling + * mbedtls_rsa_set_padding() selects the hash used for the + * encoding operation and for the mask generation function + * (MGF1). For more details on the encoding operation and the + * mask generation function, consult RFC-3447: Public-Key + * Cryptography Standards (PKCS) #1 v2.1: RSA Cryptography + * Specifications. If the \c hash_id set in \p ctx by + * mbedtls_rsa_set_padding() is #MBEDTLS_MD_NONE, the \p md_alg + * parameter is used. + * + * \param ctx The initialized RSA public key context to use. + * \param md_alg The message-digest algorithm used to hash the original data. + * Use #MBEDTLS_MD_NONE for signing raw data. + * \param hashlen The length of the message digest or raw data in Bytes. + * If \p md_alg is not #MBEDTLS_MD_NONE, this must match the + * output length of the corresponding hash algorithm. + * \param hash The buffer holding the message digest or raw data. + * This must be a readable buffer of at least \p hashlen Bytes. + * \param sig The buffer holding the signature. This must be a readable + * buffer of length \c ctx->len Bytes. For example, \c 256 Bytes + * for an 2048-bit RSA modulus. + * + * \return \c 0 if the verify operation was successful. + * \return An \c MBEDTLS_ERR_RSA_XXX error code on failure. + */ +int mbedtls_rsa_rsassa_pss_verify(mbedtls_rsa_context *ctx, + mbedtls_md_type_t md_alg, + unsigned int hashlen, + const unsigned char *hash, + const unsigned char *sig); + +/** + * \brief This function performs a PKCS#1 v2.1 PSS verification + * operation (RSASSA-PSS-VERIFY). + * + * \note The \p sig buffer must be as large as the size + * of \p ctx->N. For example, 128 Bytes if RSA-1024 is used. + * + * \note The \c hash_id set in \p ctx by mbedtls_rsa_set_padding() is + * ignored. + * + * \param ctx The initialized RSA public key context to use. + * \param md_alg The message-digest algorithm used to hash the original data. + * Use #MBEDTLS_MD_NONE for signing raw data. + * \param hashlen The length of the message digest or raw data in Bytes. + * If \p md_alg is not #MBEDTLS_MD_NONE, this must match the + * output length of the corresponding hash algorithm. + * \param hash The buffer holding the message digest or raw data. + * This must be a readable buffer of at least \p hashlen Bytes. + * \param mgf1_hash_id The message digest algorithm used for the + * verification operation and the mask generation + * function (MGF1). For more details on the encoding + * operation and the mask generation function, consult + * RFC-3447: Public-Key Cryptography Standards + * (PKCS) #1 v2.1: RSA Cryptography + * Specifications. + * \param expected_salt_len The length of the salt used in padding. Use + * #MBEDTLS_RSA_SALT_LEN_ANY to accept any salt length. + * \param sig The buffer holding the signature. This must be a readable + * buffer of length \c ctx->len Bytes. For example, \c 256 Bytes + * for an 2048-bit RSA modulus. + * + * \return \c 0 if the verify operation was successful. + * \return An \c MBEDTLS_ERR_RSA_XXX error code on failure. + */ +int mbedtls_rsa_rsassa_pss_verify_ext(mbedtls_rsa_context *ctx, + mbedtls_md_type_t md_alg, + unsigned int hashlen, + const unsigned char *hash, + mbedtls_md_type_t mgf1_hash_id, + int expected_salt_len, + const unsigned char *sig); + +/** + * \brief This function copies the components of an RSA context. + * + * \param dst The destination context. This must be initialized. + * \param src The source context. This must be initialized. + * + * \return \c 0 on success. + * \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory allocation failure. + */ +int mbedtls_rsa_copy(mbedtls_rsa_context *dst, const mbedtls_rsa_context *src); + +/** + * \brief This function frees the components of an RSA key. + * + * \param ctx The RSA context to free. May be \c NULL, in which case + * this function is a no-op. If it is not \c NULL, it must + * point to an initialized RSA context. + */ +void mbedtls_rsa_free(mbedtls_rsa_context *ctx); + +#if defined(MBEDTLS_SELF_TEST) + +/** + * \brief The RSA checkup routine. + * + * \return \c 0 on success. + * \return \c 1 on failure. + */ +int mbedtls_rsa_self_test(int verbose); + +#endif /* MBEDTLS_SELF_TEST */ + +#ifdef __cplusplus +} +#endif + +#endif /* rsa.h */ -- cgit