PK: declare restartable sign/verify functions

For RSA, we could either have the function return an error code like
NOT_IMPLEMENTED or just run while disregarding ecp_max_ops. IMO the second
option makes more sense, as otherwise the caller would need to check whether
the key is EC or RSA before deciding to call either sign() or
sign_restartable(), and having to do this kind of check feels contrary to the
goal of the PK layer.
This commit is contained in:
Manuel Pégourié-Gonnard 2017-05-03 10:59:45 +02:00
parent fd838dab5c
commit 82cb27b3db
2 changed files with 94 additions and 6 deletions

View file

@ -284,6 +284,33 @@ 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 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 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
* \param rs_ctx Restart context: for ECC, must be NULL (no restart) or a
* pointer to a \c mbedtls_ecdsa_restart_ctx. Ignored for RSA.
*
* \return See \c mbedtls_pk_verify(), or
* 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,
void *rs_ctx );
/**
* \brief Verify signature, with options.
* (Includes verification of the padding depending on type.)
@ -347,6 +374,36 @@ int mbedtls_pk_sign( mbedtls_pk_context *ctx, mbedtls_md_type_t md_alg,
unsigned char *sig, size_t *sig_len,
int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
/**
* \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 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
* \param rs_ctx Restart context: for ECC, must be NULL (no restart) or a
* pointer to a \c mbedtls_ecdsa_restart_ctx. Ignored for RSA.
*
* \return See \c mbedtls_pk_sign(), or
* 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,
void *rs_ctx );
/**
* \brief Decrypt message (including padding if relevant).
*