mbedtls/include/mbedtls/pk.h
2016-05-23 14:29:30 +01:00

617 lines
21 KiB
C

/**
* \file pk.h
*
* \brief Public Key abstraction layer
*
* Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
* 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.
*
* This file is part of mbed TLS (https://tls.mbed.org)
*/
#ifndef MBEDTLS_PK_H
#define MBEDTLS_PK_H
#if !defined(MBEDTLS_CONFIG_FILE)
#include "config.h"
#else
#include MBEDTLS_CONFIG_FILE
#endif
#include "md.h"
#if defined(MBEDTLS_RSA_C)
#include "rsa.h"
#endif
#if defined(MBEDTLS_ECP_C)
#include "ecp.h"
#endif
#if defined(MBEDTLS_ECDSA_C)
#include "ecdsa.h"
#endif
#if ( defined(__ARMCC_VERSION) || defined(_MSC_VER) ) && \
!defined(inline) && !defined(__cplusplus)
#define inline __inline
#endif
#define MBEDTLS_ERR_PK_ALLOC_FAILED -0x3F80 /**< Memory allocation failed. */
#define MBEDTLS_ERR_PK_TYPE_MISMATCH -0x3F00 /**< Type mismatch, eg attempt to encrypt with an ECDSA key */
#define MBEDTLS_ERR_PK_BAD_INPUT_DATA -0x3E80 /**< Bad input parameters to function. */
#define MBEDTLS_ERR_PK_FILE_IO_ERROR -0x3E00 /**< Read/write of file failed. */
#define MBEDTLS_ERR_PK_KEY_INVALID_VERSION -0x3D80 /**< Unsupported key version */
#define MBEDTLS_ERR_PK_KEY_INVALID_FORMAT -0x3D00 /**< Invalid key tag or value. */
#define MBEDTLS_ERR_PK_UNKNOWN_PK_ALG -0x3C80 /**< Key algorithm is unsupported (only RSA and EC are supported). */
#define MBEDTLS_ERR_PK_PASSWORD_REQUIRED -0x3C00 /**< Private key password can't be empty. */
#define MBEDTLS_ERR_PK_PASSWORD_MISMATCH -0x3B80 /**< Given private key password does not allow for correct decryption. */
#define MBEDTLS_ERR_PK_INVALID_PUBKEY -0x3B00 /**< The pubkey tag or value is invalid (only RSA and EC are supported). */
#define MBEDTLS_ERR_PK_INVALID_ALG -0x3A80 /**< The algorithm tag or value is invalid. */
#define MBEDTLS_ERR_PK_UNKNOWN_NAMED_CURVE -0x3A00 /**< Elliptic curve is unsupported (only NIST curves are supported). */
#define MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE -0x3980 /**< Unavailable feature, e.g. RSA disabled for RSA key. */
#define MBEDTLS_ERR_PK_SIG_LEN_MISMATCH -0x3900 /**< The signature is valid but its length is less than expected. */
#ifdef __cplusplus
extern "C" {
#endif
/**
* \brief Public key types
*/
typedef enum {
MBEDTLS_PK_NONE=0,
MBEDTLS_PK_RSA,
MBEDTLS_PK_ECKEY,
MBEDTLS_PK_ECKEY_DH,
MBEDTLS_PK_ECDSA,
MBEDTLS_PK_RSA_ALT,
MBEDTLS_PK_RSASSA_PSS,
} mbedtls_pk_type_t;
/**
* \brief Options for RSASSA-PSS signature verification.
* See \c mbedtls_rsa_rsassa_pss_verify_ext()
*/
typedef struct
{
mbedtls_md_type_t mgf1_hash_id;
int expected_salt_len;
} mbedtls_pk_rsassa_pss_options;
/**
* \brief Types for interfacing with the debug module
*/
typedef enum
{
MBEDTLS_PK_DEBUG_NONE = 0,
MBEDTLS_PK_DEBUG_MPI,
MBEDTLS_PK_DEBUG_ECP,
} mbedtls_pk_debug_type;
/**
* \brief Item to send to the debug module
*/
typedef struct
{
mbedtls_pk_debug_type type;
const char *name;
void *value;
} mbedtls_pk_debug_item;
/** Maximum number of item send for debugging, plus 1 */
#define MBEDTLS_PK_DEBUG_MAX_ITEMS 3
/**
* \brief Public key information and operations
*/
typedef struct mbedtls_pk_info_t mbedtls_pk_info_t;
/**
* \brief Public key container
*/
typedef struct
{
const mbedtls_pk_info_t * pk_info; /**< Public key informations */
void * pk_ctx; /**< Underlying public key context */
} mbedtls_pk_context;
#if defined(MBEDTLS_RSA_C)
/**
* Quick access to an RSA context inside a PK context.
*
* \warning You must make sure the PK context actually holds an RSA context
* before using this function!
*/
static inline mbedtls_rsa_context *mbedtls_pk_rsa( const mbedtls_pk_context pk )
{
return( (mbedtls_rsa_context *) (pk).pk_ctx );
}
#endif /* MBEDTLS_RSA_C */
#if defined(MBEDTLS_ECP_C)
/**
* Quick access to an EC context inside a PK context.
*
* \warning You must make sure the PK context actually holds an EC context
* before using this function!
*/
static inline mbedtls_ecp_keypair *mbedtls_pk_ec( const mbedtls_pk_context pk )
{
return( (mbedtls_ecp_keypair *) (pk).pk_ctx );
}
#endif /* MBEDTLS_ECP_C */
#if defined(MBEDTLS_PK_RSA_ALT_SUPPORT)
/**
* \brief Types for RSA-alt abstraction
*/
typedef int (*mbedtls_pk_rsa_alt_decrypt_func)( void *ctx, int mode, size_t *olen,
const unsigned char *input, unsigned char *output,
size_t output_max_len );
typedef int (*mbedtls_pk_rsa_alt_sign_func)( void *ctx,
int (*f_rng)(void *, unsigned char *, size_t), void *p_rng,
int mode, mbedtls_md_type_t md_alg, unsigned int hashlen,
const unsigned char *hash, unsigned char *sig );
typedef size_t (*mbedtls_pk_rsa_alt_key_len_func)( void *ctx );
#endif /* MBEDTLS_PK_RSA_ALT_SUPPORT */
/**
* \brief Return information associated with the given PK type
*
* \param pk_type PK type to search for.
*
* \return The PK info associated with the type or NULL if not found.
*/
const mbedtls_pk_info_t *mbedtls_pk_info_from_type( mbedtls_pk_type_t pk_type );
/**
* \brief Initialize a mbedtls_pk_context (as NONE)
*/
void mbedtls_pk_init( mbedtls_pk_context *ctx );
/**
* \brief Free a mbedtls_pk_context
*/
void mbedtls_pk_free( mbedtls_pk_context *ctx );
/**
* \brief Initialize a PK context with the information given
* and allocates the type-specific PK subcontext.
*
* \param ctx Context to initialize. Must be empty (type NONE).
* \param info Information to use
*
* \return 0 on success,
* MBEDTLS_ERR_PK_BAD_INPUT_DATA on invalid input,
* MBEDTLS_ERR_PK_ALLOC_FAILED on allocation failure.
*
* \note For contexts holding an RSA-alt key, use
* \c mbedtls_pk_setup_rsa_alt() instead.
*/
int mbedtls_pk_setup( mbedtls_pk_context *ctx, const mbedtls_pk_info_t *info );
#if defined(MBEDTLS_PK_RSA_ALT_SUPPORT)
/**
* \brief Initialize an RSA-alt context
*
* \param ctx Context to initialize. Must be empty (type NONE).
* \param key RSA key pointer
* \param decrypt_func Decryption function
* \param sign_func Signing function
* \param key_len_func Function returning key length in bytes
*
* \return 0 on success, or MBEDTLS_ERR_PK_BAD_INPUT_DATA if the
* context wasn't already initialized as RSA_ALT.
*
* \note This function replaces \c mbedtls_pk_setup() for RSA-alt.
*/
int mbedtls_pk_setup_rsa_alt( mbedtls_pk_context *ctx, void * key,
mbedtls_pk_rsa_alt_decrypt_func decrypt_func,
mbedtls_pk_rsa_alt_sign_func sign_func,
mbedtls_pk_rsa_alt_key_len_func key_len_func );
#endif /* MBEDTLS_PK_RSA_ALT_SUPPORT */
/**
* \brief Get the size in bits of the underlying key
*
* \param ctx Context to use
*
* \return Key size in bits, or 0 on error
*/
size_t mbedtls_pk_get_bitlen( const mbedtls_pk_context *ctx );
/**
* \brief Get the length in bytes of the underlying key
* \param ctx Context to use
*
* \return Key length in bytes, or 0 on error
*/
static inline size_t mbedtls_pk_get_len( const mbedtls_pk_context *ctx )
{
return( ( mbedtls_pk_get_bitlen( ctx ) + 7 ) / 8 );
}
/**
* \brief Tell if a context can do the operation given by type
*
* \param ctx Context to test
* \param type Target type
*
* \return 0 if context can't do the operations,
* 1 otherwise.
*/
int mbedtls_pk_can_do( const mbedtls_pk_context *ctx, mbedtls_pk_type_t type );
/**
* \brief Verify signature (including padding if relevant).
*
* \param ctx PK context to use
* \param md_alg Hash algorithm used (see notes)
* \param hash Hash of the message to sign
* \param hash_len Hash length or 0 (see notes)
* \param sig Signature to verify
* \param sig_len Signature length
*
* \return 0 on success (signature is valid),
* MBEDTLS_ERR_PK_SIG_LEN_MISMATCH if the signature is
* valid but its actual length is less than sig_len,
* or a specific error code.
*
* \note For RSA keys, the default padding type is PKCS#1 v1.5.
* Use \c mbedtls_pk_verify_ext( MBEDTLS_PK_RSASSA_PSS, ... )
* to verify RSASSA_PSS signatures.
*
* \note If hash_len is 0, then the length associated with md_alg
* is used instead, or an error returned if it is invalid.
*
* \note md_alg may be MBEDTLS_MD_NONE, only if hash_len != 0
*/
int mbedtls_pk_verify( mbedtls_pk_context *ctx, mbedtls_md_type_t md_alg,
const unsigned char *hash, size_t hash_len,
const unsigned char *sig, size_t sig_len );
/**
* \brief Verify signature, with options.
* (Includes verification of the padding depending on type.)
*
* \param type Signature type (inc. possible padding type) to verify
* \param options Pointer to type-specific options, or NULL
* \param ctx PK context to use
* \param md_alg Hash algorithm used (see notes)
* \param hash Hash of the message to sign
* \param hash_len Hash length or 0 (see notes)
* \param sig Signature to verify
* \param sig_len Signature length
*
* \return 0 on success (signature is valid),
* MBEDTLS_ERR_PK_TYPE_MISMATCH if the PK context can't be
* used for this type of signatures,
* MBEDTLS_ERR_PK_SIG_LEN_MISMATCH if the signature is
* valid but its actual length is less than sig_len,
* or a specific error code.
*
* \note If hash_len is 0, then the length associated with md_alg
* is used instead, or an error returned if it is invalid.
*
* \note md_alg may be MBEDTLS_MD_NONE, only if hash_len != 0
*
* \note If type is MBEDTLS_PK_RSASSA_PSS, then options must point
* to a mbedtls_pk_rsassa_pss_options structure,
* otherwise it must be NULL.
*/
int mbedtls_pk_verify_ext( mbedtls_pk_type_t type, const void *options,
mbedtls_pk_context *ctx, mbedtls_md_type_t md_alg,
const unsigned char *hash, size_t hash_len,
const unsigned char *sig, size_t sig_len );
/**
* \brief Make signature, including padding if relevant.
*
* \param ctx PK context to use - must hold a private key
* \param md_alg Hash algorithm used (see notes)
* \param hash Hash of the message to sign
* \param hash_len Hash length or 0 (see notes)
* \param sig Place to write the signature
* \param sig_len Number of bytes written
* \param f_rng RNG function
* \param p_rng RNG parameter
*
* \return 0 on success, or a specific error code.
*
* \note For RSA keys, the default padding type is PKCS#1 v1.5.
* There is no interface in the PK module to make RSASSA-PSS
* signatures yet.
*
* \note If hash_len is 0, then the length associated with md_alg
* is used instead, or an error returned if it is invalid.
*
* \note For RSA, md_alg may be MBEDTLS_MD_NONE if hash_len != 0.
* For ECDSA, md_alg may never be MBEDTLS_MD_NONE.
*/
int mbedtls_pk_sign( mbedtls_pk_context *ctx, mbedtls_md_type_t md_alg,
const unsigned char *hash, size_t hash_len,
unsigned char *sig, size_t *sig_len,
int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
/**
* \brief Decrypt message (including padding if relevant).
*
* \param ctx PK context to use - must hold a private key
* \param input Input to decrypt
* \param ilen Input size
* \param output Decrypted output
* \param olen Decrypted message length
* \param osize Size of the output buffer
* \param f_rng RNG function
* \param p_rng RNG parameter
*
* \note For RSA keys, the default padding type is PKCS#1 v1.5.
*
* \return 0 on success, or a specific error code.
*/
int mbedtls_pk_decrypt( mbedtls_pk_context *ctx,
const unsigned char *input, size_t ilen,
unsigned char *output, size_t *olen, size_t osize,
int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
/**
* \brief Encrypt message (including padding if relevant).
*
* \param ctx PK context to use
* \param input Message to encrypt
* \param ilen Message size
* \param output Encrypted output
* \param olen Encrypted output length
* \param osize Size of the output buffer
* \param f_rng RNG function
* \param p_rng RNG parameter
*
* \note For RSA keys, the default padding type is PKCS#1 v1.5.
*
* \return 0 on success, or a specific error code.
*/
int mbedtls_pk_encrypt( mbedtls_pk_context *ctx,
const unsigned char *input, size_t ilen,
unsigned char *output, size_t *olen, size_t osize,
int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
/**
* \brief Check if a public-private pair of keys matches.
*
* \param pub Context holding a public key.
* \param prv Context holding a private (and public) key.
*
* \return 0 on success or MBEDTLS_ERR_PK_BAD_INPUT_DATA
*/
int mbedtls_pk_check_pair( const mbedtls_pk_context *pub, const mbedtls_pk_context *prv );
/**
* \brief Export debug information
*
* \param ctx Context to use
* \param items Place to write debug items
*
* \return 0 on success or MBEDTLS_ERR_PK_BAD_INPUT_DATA
*/
int mbedtls_pk_debug( const mbedtls_pk_context *ctx, mbedtls_pk_debug_item *items );
/**
* \brief Access the type name
*
* \param ctx Context to use
*
* \return Type name on success, or "invalid PK"
*/
const char * mbedtls_pk_get_name( const mbedtls_pk_context *ctx );
/**
* \brief Get the key type
*
* \param ctx Context to use
*
* \return Type on success, or MBEDTLS_PK_NONE
*/
mbedtls_pk_type_t mbedtls_pk_get_type( const mbedtls_pk_context *ctx );
#if defined(MBEDTLS_PK_PARSE_C)
/** \ingroup pk_module */
/**
* \brief Parse a private key in PEM or DER format
*
* \param ctx key to be initialized
* \param key input buffer
* \param keylen size of the buffer
* (including the terminating null byte for PEM data)
* \param pwd password for decryption (optional)
* \param pwdlen size of the password
*
* \note On entry, ctx must be empty, either freshly initialised
* with mbedtls_pk_init() or reset with mbedtls_pk_free(). If you need a
* specific key type, check the result with mbedtls_pk_can_do().
*
* \note The key is also checked for correctness.
*
* \return 0 if successful, or a specific PK or PEM error code
*/
int mbedtls_pk_parse_key( mbedtls_pk_context *ctx,
const unsigned char *key, size_t keylen,
const unsigned char *pwd, size_t pwdlen );
/** \ingroup pk_module */
/**
* \brief Parse a public key in PEM or DER format
*
* \param ctx key to be initialized
* \param key input buffer
* \param keylen size of the buffer
* (including the terminating null byte for PEM data)
*
* \note On entry, ctx must be empty, either freshly initialised
* with mbedtls_pk_init() or reset with mbedtls_pk_free(). If you need a
* specific key type, check the result with mbedtls_pk_can_do().
*
* \note The key is also checked for correctness.
*
* \return 0 if successful, or a specific PK or PEM error code
*/
int mbedtls_pk_parse_public_key( mbedtls_pk_context *ctx,
const unsigned char *key, size_t keylen );
#if defined(MBEDTLS_FS_IO)
/** \ingroup pk_module */
/**
* \brief Load and parse a private key
*
* \param ctx key to be initialized
* \param path filename to read the private key from
* \param password password to decrypt the file (can be NULL)
*
* \note On entry, ctx must be empty, either freshly initialised
* with mbedtls_pk_init() or reset with mbedtls_pk_free(). If you need a
* specific key type, check the result with mbedtls_pk_can_do().
*
* \note The key is also checked for correctness.
*
* \return 0 if successful, or a specific PK or PEM error code
*/
int mbedtls_pk_parse_keyfile( mbedtls_pk_context *ctx,
const char *path, const char *password );
/** \ingroup pk_module */
/**
* \brief Load and parse a public key
*
* \param ctx key to be initialized
* \param path filename to read the public key from
*
* \note On entry, ctx must be empty, either freshly initialised
* with mbedtls_pk_init() or reset with mbedtls_pk_free(). If
* you need a specific key type, check the result with
* mbedtls_pk_can_do().
*
* \note The key is also checked for correctness.
*
* \return 0 if successful, or a specific PK or PEM error code
*/
int mbedtls_pk_parse_public_keyfile( mbedtls_pk_context *ctx, const char *path );
#endif /* MBEDTLS_FS_IO */
#endif /* MBEDTLS_PK_PARSE_C */
#if defined(MBEDTLS_PK_WRITE_C)
/**
* \brief Write a private key to a PKCS#1 or SEC1 DER structure
* Note: data is written at the end of the buffer! Use the
* return value to determine where you should start
* using the buffer
*
* \param ctx private to write away
* \param buf buffer to write to
* \param size size of the buffer
*
* \return length of data written if successful, or a specific
* error code
*/
int mbedtls_pk_write_key_der( mbedtls_pk_context *ctx, unsigned char *buf, size_t size );
/**
* \brief Write a public key to a SubjectPublicKeyInfo DER structure
* Note: data is written at the end of the buffer! Use the
* return value to determine where you should start
* using the buffer
*
* \param ctx public key to write away
* \param buf buffer to write to
* \param size size of the buffer
*
* \return length of data written if successful, or a specific
* error code
*/
int mbedtls_pk_write_pubkey_der( mbedtls_pk_context *ctx, unsigned char *buf, size_t size );
#if defined(MBEDTLS_PEM_WRITE_C)
/**
* \brief Write a public key to a PEM string
*
* \param ctx public key to write away
* \param buf buffer to write to
* \param size size of the buffer
*
* \return 0 if successful, or a specific error code
*/
int mbedtls_pk_write_pubkey_pem( mbedtls_pk_context *ctx, unsigned char *buf, size_t size );
/**
* \brief Write a private key to a PKCS#1 or SEC1 PEM string
*
* \param ctx private to write away
* \param buf buffer to write to
* \param size size of the buffer
*
* \return 0 if successful, or a specific error code
*/
int mbedtls_pk_write_key_pem( mbedtls_pk_context *ctx, unsigned char *buf, size_t size );
#endif /* MBEDTLS_PEM_WRITE_C */
#endif /* MBEDTLS_PK_WRITE_C */
/*
* WARNING: Low-level functions. You probably do not want to use these unless
* you are certain you do ;)
*/
#if defined(MBEDTLS_PK_PARSE_C)
/**
* \brief Parse a SubjectPublicKeyInfo DER structure
*
* \param p the position in the ASN.1 data
* \param end end of the buffer
* \param pk the key to fill
*
* \return 0 if successful, or a specific PK error code
*/
int mbedtls_pk_parse_subpubkey( unsigned char **p, const unsigned char *end,
mbedtls_pk_context *pk );
#endif /* MBEDTLS_PK_PARSE_C */
#if defined(MBEDTLS_PK_WRITE_C)
/**
* \brief Write a subjectPublicKey to ASN.1 data
* Note: function works backwards in data buffer
*
* \param p reference to current position pointer
* \param start start of the buffer (for bounds-checking)
* \param key public key to write away
*
* \return the length written or a negative error code
*/
int mbedtls_pk_write_pubkey( unsigned char **p, unsigned char *start,
const mbedtls_pk_context *key );
#endif /* MBEDTLS_PK_WRITE_C */
/*
* Internal module functions. You probably do not want to use these unless you
* know you do.
*/
#if defined(MBEDTLS_FS_IO)
int mbedtls_pk_load_file( const char *path, unsigned char **buf, size_t *n );
#endif
#ifdef __cplusplus
}
#endif
#endif /* MBEDTLS_PK_H */