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/* ====================================================================
* Copyright (c) 1998-2005 The OpenSSL Project. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. All advertising materials mentioning features or use of this
* software must display the following acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
*
* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
* endorse or promote products derived from this software without
* prior written permission. For written permission, please contact
* openssl-core@OpenSSL.org.
*
* 5. Products derived from this software may not be called "OpenSSL"
* nor may "OpenSSL" appear in their names without prior written
* permission of the OpenSSL Project.
*
* 6. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
*
* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
* ====================================================================
*
* This product includes cryptographic software written by Eric Young
* (eay@cryptsoft.com). This product includes software written by Tim
* Hudson (tjh@cryptsoft.com). */
#ifndef OPENSSL_HEADER_ECDSA_H
#define OPENSSL_HEADER_ECDSA_H
#include <openssl/base.h>
#include <openssl/ec_key.h>
#if defined(__cplusplus)
extern "C" {
#endif
/* ECDSA contains functions for signing and verifying with the Digital Signature
* Algorithm over elliptic curves. */
/* Signing and verifing. */
/* ECDSA_sign signs |digest_len| bytes from |digest| with |key| and writes the
* resulting signature to |sig|, which must have |ECDSA_size(key)| bytes of
* space. On successful exit, |*sig_len| is set to the actual number of bytes
* written. The |type| argument should be zero. It returns one on success and
* zero otherwise. */
OPENSSL_EXPORT int ECDSA_sign(int type, const uint8_t *digest,
size_t digest_len, uint8_t *sig,
unsigned int *sig_len, EC_KEY *key);
/* ECDSA_verify verifies that |sig_len| bytes from |sig| constitute a valid
* signature by |key| of |digest|. (The |type| argument should be zero.) It
* returns one on success or zero if the signature is invalid or an error
* occured. */
OPENSSL_EXPORT int ECDSA_verify(int type, const uint8_t *digest,
size_t digest_len, const uint8_t *sig,
size_t sig_len, EC_KEY *key);
/* ECDSA_size returns the maximum size of an ECDSA signature using |key|. It
* returns zero on error. */
OPENSSL_EXPORT size_t ECDSA_size(const EC_KEY *key);
/* Low-level signing and verification.
*
* Low-level functions handle signatures as |ECDSA_SIG| structures which allow
* the two values in an ECDSA signature to be handled separately. */
struct ecdsa_sig_st {
BIGNUM *r;
BIGNUM *s;
};
/* ECDSA_SIG_new returns a fresh |ECDSA_SIG| structure or NULL on error. */
OPENSSL_EXPORT ECDSA_SIG *ECDSA_SIG_new(void);
/* ECDSA_SIG_free frees |sig| its member |BIGNUM|s. */
OPENSSL_EXPORT void ECDSA_SIG_free(ECDSA_SIG *sig);
/* ECDSA_sign signs |digest_len| bytes from |digest| with |key| and returns the
* resulting signature structure, or NULL on error. */
OPENSSL_EXPORT ECDSA_SIG *ECDSA_do_sign(const uint8_t *digest,
size_t digest_len, EC_KEY *key);
/* ECDSA_verify verifies that |sig| constitutes a valid signature by |key| of
* |digest|. It returns one on success or zero if the signature is invalid or
* on error. */
OPENSSL_EXPORT int ECDSA_do_verify(const uint8_t *digest, size_t digest_len,
const ECDSA_SIG *sig, EC_KEY *key);
/* Signing with precomputation.
*
* Parts of the ECDSA signature can be independent of the message to be signed
* thus it's possible to precompute them and reduce the signing latency.
*
* TODO(fork): remove support for this as it cannot support safe-randomness. */
/* ECDSA_sign_setup precomputes parts of an ECDSA signing operation. It sets
* |*kinv| and |*rp| to the precomputed values and uses the |ctx| argument, if
* not NULL. It returns one on success and zero otherwise. */
OPENSSL_EXPORT int ECDSA_sign_setup(EC_KEY *eckey, BN_CTX *ctx, BIGNUM **kinv,
BIGNUM **rp);
/* ECDSA_do_sign_ex is the same as |ECDSA_do_sign| but takes precomputed values
* as generated by |ECDSA_sign_setup|. */
OPENSSL_EXPORT ECDSA_SIG *ECDSA_do_sign_ex(const uint8_t *digest,
size_t digest_len,
const BIGNUM *kinv, const BIGNUM *rp,
EC_KEY *eckey);
/* ECDSA_sign_ex is the same as |ECDSA_sign| but takes precomputed values as
* generated by |ECDSA_sign_setup|. */
OPENSSL_EXPORT int ECDSA_sign_ex(int type, const uint8_t *digest,
size_t digest_len, uint8_t *sig,
unsigned int *sig_len, const BIGNUM *kinv,
const BIGNUM *rp, EC_KEY *eckey);
/* ASN.1 functions. */
/* ECDSA_SIG_parse parses a DER-encoded ECDSA-Sig-Value structure from |cbs| and
* advances |cbs|. It returns a newly-allocated |ECDSA_SIG| or NULL on error. */
OPENSSL_EXPORT ECDSA_SIG *ECDSA_SIG_parse(CBS *cbs);
/* ECDSA_SIG_from_bytes parses |in| as a DER-encoded ECDSA-Sig-Value structure.
* It returns a newly-allocated |ECDSA_SIG| structure or NULL on error. */
OPENSSL_EXPORT ECDSA_SIG *ECDSA_SIG_from_bytes(const uint8_t *in,
size_t in_len);
/* ECDSA_SIG_marshal marshals |sig| as a DER-encoded ECDSA-Sig-Value and appends
* the result to |cbb|. It returns one on success and zero on error. */
OPENSSL_EXPORT int ECDSA_SIG_marshal(CBB *cbb, const ECDSA_SIG *sig);
/* ECDSA_SIG_to_asn1 marshals |sig| as a DER-encoded ECDSA-Sig-Value and, on
* success, sets |*out_bytes| to a newly allocated buffer containing the result
* and returns one. Otherwise, it returns zero. The result should be freed with
* |OPENSSL_free|. */
OPENSSL_EXPORT int ECDSA_SIG_to_bytes(uint8_t **out_bytes, size_t *out_len,
const ECDSA_SIG *sig);
/* ECDSA_SIG_max_len returns the maximum length of a DER-encoded ECDSA-Sig-Value
* structure for a group whose order is represented in |order_len| bytes, or
* zero on overflow. */
OPENSSL_EXPORT size_t ECDSA_SIG_max_len(size_t order_len);
/* Deprecated functions. */
/* d2i_ECDSA_SIG parses an ASN.1, DER-encoded, signature from |len| bytes at
* |*inp|. If |out| is not NULL then, on exit, a pointer to the result is in
* |*out|. If |*out| is already non-NULL on entry then the result is written
* directly into |*out|, otherwise a fresh |ECDSA_SIG| is allocated. On
* successful exit, |*inp| is advanced past the DER structure. It returns the
* result or NULL on error. */
OPENSSL_EXPORT ECDSA_SIG *d2i_ECDSA_SIG(ECDSA_SIG **out, const uint8_t **inp,
long len);
/* i2d_ECDSA_SIG marshals a signature from |sig| to an ASN.1, DER
* structure. If |outp| is not NULL then the result is written to |*outp| and
* |*outp| is advanced just past the output. It returns the number of bytes in
* the result, whether written or not, or a negative value on error. */
OPENSSL_EXPORT int i2d_ECDSA_SIG(const ECDSA_SIG *sig, uint8_t **outp);
#if defined(__cplusplus)
} /* extern C */
#endif
#define ECDSA_R_BAD_SIGNATURE 100
#define ECDSA_R_MISSING_PARAMETERS 101
#define ECDSA_R_NEED_NEW_SETUP_VALUES 102
#define ECDSA_R_NOT_IMPLEMENTED 103
#define ECDSA_R_RANDOM_NUMBER_GENERATION_FAILED 104
#define ECDSA_R_ENCODE_ERROR 105
#endif /* OPENSSL_HEADER_ECDSA_H */