cosmopolitan/third_party/mbedtls/pk.c
2022-07-21 21:46:07 -07:00

721 lines
27 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:4;tab-width:4;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright The Mbed TLS Contributors │
│ │
│ 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. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "third_party/mbedtls/common.h"
#include "third_party/mbedtls/ecdsa.h"
#include "third_party/mbedtls/ecp.h"
#include "third_party/mbedtls/error.h"
#include "third_party/mbedtls/pk.h"
#include "third_party/mbedtls/pk_internal.h"
#include "third_party/mbedtls/platform.h"
#include "third_party/mbedtls/rsa.h"
asm(".ident\t\"\\n\\n\
Mbed TLS (Apache 2.0)\\n\
Copyright ARM Limited\\n\
Copyright Mbed TLS Contributors\"");
asm(".include \"libc/disclaimer.inc\"");
/* clang-format off */
/**
* @fileoverview Public Key abstraction layer
*/
#if defined(MBEDTLS_PK_C)
#define PK_VALIDATE_RET( cond ) \
MBEDTLS_INTERNAL_VALIDATE_RET( cond, MBEDTLS_ERR_PK_BAD_INPUT_DATA )
#define PK_VALIDATE( cond ) \
MBEDTLS_INTERNAL_VALIDATE( cond )
/**
* \brief Initialize a #mbedtls_pk_context (as NONE).
*
* \param ctx The context to initialize.
* This must not be \c NULL.
*/
void mbedtls_pk_init( mbedtls_pk_context *ctx )
{
PK_VALIDATE( ctx );
ctx->pk_info = NULL;
ctx->pk_ctx = NULL;
}
/**
* \brief Free the components of a #mbedtls_pk_context.
*
* \param ctx The context to clear. It must have been initialized.
* If this is \c NULL, this function does nothing.
*
* \note For contexts that have been set up with
* mbedtls_pk_setup_opaque(), this does not free the underlying
* PSA key and you still need to call psa_destroy_key()
* independently if you want to destroy that key.
*/
void mbedtls_pk_free( mbedtls_pk_context *ctx )
{
if( ctx == NULL )
return;
if ( ctx->pk_info )
ctx->pk_info->ctx_free_func( ctx->pk_ctx );
mbedtls_platform_zeroize( ctx, sizeof( mbedtls_pk_context ) );
}
#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
/**
* \brief Initialize a restart context
*
* \param ctx The context to initialize.
* This must not be \c NULL.
*/
void mbedtls_pk_restart_init( mbedtls_pk_restart_ctx *ctx )
{
PK_VALIDATE( ctx );
ctx->pk_info = NULL;
ctx->rs_ctx = NULL;
}
/**
* \brief Free the components of a restart context
*
* \param ctx The context to clear. It must have been initialized.
* If this is \c NULL, this function does nothing.
*/
void mbedtls_pk_restart_free( mbedtls_pk_restart_ctx *ctx )
{
if( ctx == NULL || ctx->pk_info == NULL ||
ctx->pk_info->rs_free_func == NULL )
{
return;
}
ctx->pk_info->rs_free_func( ctx->rs_ctx );
ctx->pk_info = NULL;
ctx->rs_ctx = NULL;
}
#endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
/**
* \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 )
{
switch( pk_type ) {
#if defined(MBEDTLS_RSA_C)
case MBEDTLS_PK_RSA:
return( &mbedtls_rsa_info );
#endif
#if defined(MBEDTLS_ECP_C)
case MBEDTLS_PK_ECKEY:
return( &mbedtls_eckey_info );
case MBEDTLS_PK_ECKEY_DH:
return( &mbedtls_eckeydh_info );
#endif
#if defined(MBEDTLS_ECDSA_C)
case MBEDTLS_PK_ECDSA:
return( &mbedtls_ecdsa_info );
#endif
/* MBEDTLS_PK_RSA_ALT omitted on purpose */
default:
return( NULL );
}
}
/**
* \brief Initialize a PK context with the information given
* and allocates the type-specific PK subcontext.
*
* \param ctx Context to initialize. It must not have been set
* up yet (type #MBEDTLS_PK_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 )
{
PK_VALIDATE_RET( ctx );
if( info == NULL || ctx->pk_info )
return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
if( ( ctx->pk_ctx = info->ctx_alloc_func() ) == NULL )
return( MBEDTLS_ERR_PK_ALLOC_FAILED );
ctx->pk_info = info;
return( 0 );
}
/**
* \brief Initialize an RSA-alt context
*
* \param ctx Context to initialize. It must not have been set
* up yet (type #MBEDTLS_PK_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 )
{
mbedtls_rsa_alt_context *rsa_alt;
const mbedtls_pk_info_t *info = &mbedtls_rsa_alt_info;
PK_VALIDATE_RET( ctx );
if( ctx->pk_info )
return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
if( ( ctx->pk_ctx = info->ctx_alloc_func() ) == NULL )
return( MBEDTLS_ERR_PK_ALLOC_FAILED );
ctx->pk_info = info;
rsa_alt = (mbedtls_rsa_alt_context *) ctx->pk_ctx;
rsa_alt->key = key;
rsa_alt->decrypt_func = decrypt_func;
rsa_alt->sign_func = sign_func;
rsa_alt->key_len_func = key_len_func;
return( 0 );
}
/**
* \brief Tell if a context can do the operation given by type
*
* \param ctx The context to query. It must have been initialized.
* \param type The desired type.
*
* \return 1 if the context can do operations on the given type.
* \return 0 if the context cannot do the operations on the given
* type. This is always the case for a context that has
* been initialized but not set up, or that has been
* cleared with mbedtls_pk_free().
*/
int mbedtls_pk_can_do( const mbedtls_pk_context *ctx, mbedtls_pk_type_t type )
{
/* A context with null pk_info is not set up yet and can't do anything.
* For backward compatibility, also accept NULL instead of a context
* pointer. */
if( ctx == NULL || ctx->pk_info == NULL )
return( 0 );
return( ctx->pk_info->can_do( type ) );
}
/*
* Helper for mbedtls_pk_sign and mbedtls_pk_verify
*/
static inline int pk_hashlen_helper( mbedtls_md_type_t md_alg, size_t *hash_len )
{
const mbedtls_md_info_t *md_info;
if( *hash_len != 0 )
return( 0 );
if( ( md_info = mbedtls_md_info_from_type( md_alg ) ) == NULL )
return( -1 );
*hash_len = mbedtls_md_get_size( md_info );
return( 0 );
}
#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
/*
* Helper to set up a restart context if needed
*/
static int pk_restart_setup( mbedtls_pk_restart_ctx *ctx,
const mbedtls_pk_info_t *info )
{
/* Don't do anything if already set up or invalid */
if( ctx == NULL || ctx->pk_info )
return( 0 );
/* Should never happen when we're called */
if( info->rs_alloc_func == NULL || info->rs_free_func == NULL )
return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
if( ( ctx->rs_ctx = info->rs_alloc_func() ) == NULL )
return( MBEDTLS_ERR_PK_ALLOC_FAILED );
ctx->pk_info = info;
return( 0 );
}
#endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
/**
* \brief Restartable version of \c mbedtls_pk_verify()
*
* \note Performs the same job as \c mbedtls_pk_verify(), but can
* return early and restart according to the limit set with
* \c mbedtls_ecp_set_max_ops() to reduce blocking for ECC
* operations. For RSA, same as \c mbedtls_pk_verify().
*
* \param ctx The PK context to use. It must have been set up.
* \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
* \param rs_ctx Restart context (NULL to disable restart)
*
* \return See \c mbedtls_pk_verify(), or
* \return #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
* operations was reached: see \c mbedtls_ecp_set_max_ops().
*/
int mbedtls_pk_verify_restartable( 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,
mbedtls_pk_restart_ctx *rs_ctx )
{
PK_VALIDATE_RET( ctx );
PK_VALIDATE_RET( ( md_alg == MBEDTLS_MD_NONE && hash_len == 0 ) ||
hash );
PK_VALIDATE_RET( sig );
if( ctx->pk_info == NULL ||
pk_hashlen_helper( md_alg, &hash_len ) != 0 )
return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
/* optimization: use non-restartable version if restart disabled */
if( rs_ctx &&
mbedtls_ecp_restart_is_enabled() &&
ctx->pk_info->verify_rs_func )
{
int ret = MBEDTLS_ERR_THIS_CORRUPTION;
if( ( ret = pk_restart_setup( rs_ctx, ctx->pk_info ) ) != 0 )
return( ret );
ret = ctx->pk_info->verify_rs_func( ctx->pk_ctx,
md_alg, hash, hash_len, sig, sig_len, rs_ctx->rs_ctx );
if( ret != MBEDTLS_ERR_ECP_IN_PROGRESS )
mbedtls_pk_restart_free( rs_ctx );
return( ret );
}
#else /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
(void) rs_ctx;
#endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
if( ctx->pk_info->verify_func == NULL )
return( MBEDTLS_ERR_PK_TYPE_MISMATCH );
return( ctx->pk_info->verify_func( ctx->pk_ctx, md_alg, hash, hash_len,
sig, sig_len ) );
}
/**
* \brief Verify signature (including padding if relevant).
*
* \param ctx The PK context to use. It must have been set up.
* \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 there is a valid
* signature in sig but its length is less than \p siglen,
* 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 )
{
return( mbedtls_pk_verify_restartable( ctx, md_alg, hash, hash_len,
sig, sig_len, NULL ) );
}
/**
* \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 The PK context to use. It must have been set up.
* \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 there is a valid
* signature in sig but its length is less than \p siglen,
* 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 )
{
PK_VALIDATE_RET( ctx );
PK_VALIDATE_RET( ( md_alg == MBEDTLS_MD_NONE && hash_len == 0 ) ||
hash );
PK_VALIDATE_RET( sig );
if( ctx->pk_info == NULL )
return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
if( ! mbedtls_pk_can_do( ctx, type ) )
return( MBEDTLS_ERR_PK_TYPE_MISMATCH );
if( type == MBEDTLS_PK_RSASSA_PSS )
{
#if defined(MBEDTLS_RSA_C) && defined(MBEDTLS_PKCS1_V21)
int ret = MBEDTLS_ERR_THIS_CORRUPTION;
const mbedtls_pk_rsassa_pss_options *pss_opts;
#if SIZE_MAX > UINT_MAX
if( md_alg == MBEDTLS_MD_NONE && UINT_MAX < hash_len )
return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
#endif /* SIZE_MAX > UINT_MAX */
if( options == NULL )
return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
pss_opts = (const mbedtls_pk_rsassa_pss_options *) options;
if( sig_len < mbedtls_pk_get_len( ctx ) )
return( MBEDTLS_ERR_RSA_VERIFY_FAILED );
ret = mbedtls_rsa_rsassa_pss_verify_ext( mbedtls_pk_rsa( *ctx ),
NULL, NULL, MBEDTLS_RSA_PUBLIC,
md_alg, (unsigned int) hash_len, hash,
pss_opts->mgf1_hash_id,
pss_opts->expected_salt_len,
sig );
if( ret != 0 )
return( ret );
if( sig_len > mbedtls_pk_get_len( ctx ) )
return( MBEDTLS_ERR_PK_SIG_LEN_MISMATCH );
return( 0 );
#else
return( MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE );
#endif /* MBEDTLS_RSA_C && MBEDTLS_PKCS1_V21 */
}
/* General case: no options */
if( options )
return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
return( mbedtls_pk_verify( ctx, md_alg, hash, hash_len, sig, sig_len ) );
}
/**
* \brief Restartable version of \c mbedtls_pk_sign()
*
* \note Performs the same job as \c mbedtls_pk_sign(), but can
* return early and restart according to the limit set with
* \c mbedtls_ecp_set_max_ops() to reduce blocking for ECC
* operations. For RSA, same as \c mbedtls_pk_sign().
*
* \param ctx The PK context to use. It must have been set up
* with a private key.
* \param md_alg Hash algorithm used (see notes for mbedtls_pk_sign())
* \param hash Hash of the message to sign
* \param hash_len Hash length or 0 (see notes for mbedtls_pk_sign())
* \param sig Place to write the signature.
* It must have enough room for the signature.
* #MBEDTLS_PK_SIGNATURE_MAX_SIZE is always enough.
* You may use a smaller buffer if it is large enough
* given the key type.
* \param sig_len On successful return,
* the number of bytes written to \p sig.
* \param f_rng RNG function
* \param p_rng RNG parameter
* \param rs_ctx Restart context (NULL to disable restart)
*
* \return See \c mbedtls_pk_sign().
* \return #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
* operations was reached: see \c mbedtls_ecp_set_max_ops().
*/
int mbedtls_pk_sign_restartable( 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, mbedtls_pk_restart_ctx *rs_ctx )
{
PK_VALIDATE_RET( ctx );
PK_VALIDATE_RET( ( md_alg == MBEDTLS_MD_NONE && hash_len == 0 ) ||
hash );
PK_VALIDATE_RET( sig );
if( ctx->pk_info == NULL ||
pk_hashlen_helper( md_alg, &hash_len ) != 0 )
return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
/* optimization: use non-restartable version if restart disabled */
if( rs_ctx &&
mbedtls_ecp_restart_is_enabled() &&
ctx->pk_info->sign_rs_func )
{
int ret = MBEDTLS_ERR_THIS_CORRUPTION;
if( ( ret = pk_restart_setup( rs_ctx, ctx->pk_info ) ) != 0 )
return( ret );
ret = ctx->pk_info->sign_rs_func( ctx->pk_ctx, md_alg,
hash, hash_len, sig, sig_len, f_rng, p_rng, rs_ctx->rs_ctx );
if( ret != MBEDTLS_ERR_ECP_IN_PROGRESS )
mbedtls_pk_restart_free( rs_ctx );
return( ret );
}
#else /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
(void) rs_ctx;
#endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
if( ctx->pk_info->sign_func == NULL )
return( MBEDTLS_ERR_PK_TYPE_MISMATCH );
return( ctx->pk_info->sign_func( ctx->pk_ctx, md_alg, hash, hash_len,
sig, sig_len, f_rng, p_rng ) );
}
/**
* \brief Make signature, including padding if relevant.
*
* \param ctx The PK context to use. It must have been set up
* with 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.
* It must have enough room for the signature.
* #MBEDTLS_PK_SIGNATURE_MAX_SIZE is always enough.
* You may use a smaller buffer if it is large enough
* given the key type.
* \param sig_len On successful return,
* the number of bytes written to \p sig.
* \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 )
{
return( mbedtls_pk_sign_restartable( ctx, md_alg, hash, hash_len,
sig, sig_len, f_rng, p_rng, NULL ) );
}
/**
* \brief Decrypt message (including padding if relevant).
*
* \param ctx The PK context to use. It must have been set up
* with 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 )
{
PK_VALIDATE_RET( ctx );
PK_VALIDATE_RET( input || ilen == 0 );
PK_VALIDATE_RET( output || osize == 0 );
PK_VALIDATE_RET( olen );
if( ctx->pk_info == NULL )
return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
if( ctx->pk_info->decrypt_func == NULL )
return( MBEDTLS_ERR_PK_TYPE_MISMATCH );
return( ctx->pk_info->decrypt_func( ctx->pk_ctx, input, ilen,
output, olen, osize, f_rng, p_rng ) );
}
/**
* \brief Encrypt message (including padding if relevant).
*
* \param ctx The PK context to use. It must have been set up.
* \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 )
{
PK_VALIDATE_RET( ctx );
PK_VALIDATE_RET( input || ilen == 0 );
PK_VALIDATE_RET( output || osize == 0 );
PK_VALIDATE_RET( olen );
if( ctx->pk_info == NULL )
return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
if( ctx->pk_info->encrypt_func == NULL )
return( MBEDTLS_ERR_PK_TYPE_MISMATCH );
return( ctx->pk_info->encrypt_func( ctx->pk_ctx, input, ilen,
output, olen, osize, f_rng, 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 \c 0 on success (keys were checked and match each other).
* \return #MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE if the keys could not
* be checked - in that case they may or may not match.
* \return #MBEDTLS_ERR_PK_BAD_INPUT_DATA if a context is invalid.
* \return Another non-zero value if the keys do not match.
*/
int mbedtls_pk_check_pair( const mbedtls_pk_context *pub, const mbedtls_pk_context *prv )
{
PK_VALIDATE_RET( pub );
PK_VALIDATE_RET( prv );
if( pub->pk_info == NULL ||
prv->pk_info == NULL )
{
return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
}
if( prv->pk_info->check_pair_func == NULL )
return( MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE );
if( prv->pk_info->type == MBEDTLS_PK_RSA_ALT )
{
if( pub->pk_info->type != MBEDTLS_PK_RSA )
return( MBEDTLS_ERR_PK_TYPE_MISMATCH );
}
else
{
if( pub->pk_info != prv->pk_info )
return( MBEDTLS_ERR_PK_TYPE_MISMATCH );
}
return( prv->pk_info->check_pair_func( pub->pk_ctx, prv->pk_ctx ) );
}
/**
* \brief Get the size in bits of the underlying key
*
* \param ctx The context to query. It must have been initialized.
*
* \return Key size in bits, or 0 on error
*/
size_t mbedtls_pk_get_bitlen( const mbedtls_pk_context *ctx )
{
/* For backward compatibility, accept NULL or a context that
* isn't set up yet, and return a fake value that should be safe. */
if( ctx == NULL || ctx->pk_info == NULL )
return( 0 );
return( ctx->pk_info->get_bitlen( ctx->pk_ctx ) );
}
/**
* \brief Export debug information
*
* \param ctx The PK context to use. It must have been initialized.
* \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 )
{
PK_VALIDATE_RET( ctx );
if( ctx->pk_info == NULL )
return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
if( ctx->pk_info->debug_func == NULL )
return( MBEDTLS_ERR_PK_TYPE_MISMATCH );
ctx->pk_info->debug_func( ctx->pk_ctx, items );
return( 0 );
}
/**
* \brief Access the type name
*
* \param ctx The PK context to use. It must have been initialized.
*
* \return Type name on success, or "invalid PK"
*/
const char *mbedtls_pk_get_name( const mbedtls_pk_context *ctx )
{
if( ctx == NULL || ctx->pk_info == NULL )
return( "invalid PK" );
return( ctx->pk_info->name );
}
/**
* \brief Get the key type
*
* \param ctx The PK context to use. It must have been initialized.
*
* \return Type on success.
* \return #MBEDTLS_PK_NONE for a context that has not been set up.
*/
mbedtls_pk_type_t mbedtls_pk_get_type( const mbedtls_pk_context *ctx )
{
if( ctx == NULL || ctx->pk_info == NULL )
return( MBEDTLS_PK_NONE );
return( ctx->pk_info->type );
}
#endif /* MBEDTLS_PK_C */