include/openssl/ecdsa.h - boringssl - Git at Google

 // Copyright 2002-2016 The OpenSSL Project Authors. All Rights Reserved.
 //
 // 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
 //
 //     https://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.

 #ifndef OPENSSL_HEADER_ECDSA_H
 #define OPENSSL_HEADER_ECDSA_H

 #include <openssl/base.h>   // IWYU pragma: export

 #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 verifying.
 //
 // ECDSA does not have a single, common signature format across all
 // applications. These functions implement the more common, ASN.1-based format.
 // In it, signatures are a DER-encoded ECDSA-Sig-Value structure. Note that this
 // format is variable-length. Callers must be prepared to receive signatures
 // that are slightly shorter than the maximum for the ECDSA curve.

 // ECDSA_sign signs `digest_len` bytes from `digest` with `key` and writes the
 // resulting ASN.1-based 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.
 //
 // WARNING: `digest` must be the output of some hash function on the data to be
 // signed. Passing unhashed inputs will not result in a secure signature scheme.
 OPENSSL_EXPORT int ECDSA_sign(int type, const uint8_t *digest,
                               size_t digest_len, uint8_t *sig,
                               unsigned int *sig_len, const EC_KEY *key);

 // ECDSA_verify verifies that `sig_len` bytes from `sig` constitute a valid
 // ASN.1-based 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 occurred.
 //
 // WARNING: `digest` must be the output of some hash function on the data to be
 // verified. Passing unhashed inputs will not result in a secure signature
 // scheme.
 OPENSSL_EXPORT int ECDSA_verify(int type, const uint8_t *digest,
                                 size_t digest_len, const uint8_t *sig,
                                 size_t sig_len, const EC_KEY *key);

 // ECDSA_size returns the maximum size of an ASN.1-based ECDSA signature using
 // `key`. It returns zero if `key` is NULL or if it doesn't have a group set.
 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_SIG_get0_r returns the r component of `sig`.
 OPENSSL_EXPORT const BIGNUM *ECDSA_SIG_get0_r(const ECDSA_SIG *sig);

 // ECDSA_SIG_get0_s returns the s component of `sig`.
 OPENSSL_EXPORT const BIGNUM *ECDSA_SIG_get0_s(const ECDSA_SIG *sig);

 // ECDSA_SIG_get0 sets `*out_r` and `*out_s`, if non-NULL, to the two
 // components of `sig`.
 OPENSSL_EXPORT void ECDSA_SIG_get0(const ECDSA_SIG *sig, const BIGNUM **out_r,
                                    const BIGNUM **out_s);

 // ECDSA_SIG_set0 sets `sig`'s components to `r` and `s`, neither of which may
 // be NULL. On success, it takes ownership of each argument and returns one.
 // Otherwise, it returns zero.
 OPENSSL_EXPORT int ECDSA_SIG_set0(ECDSA_SIG *sig, BIGNUM *r, BIGNUM *s);

 // ECDSA_do_sign signs `digest_len` bytes from `digest` with `key` and returns
 // the resulting signature structure, or NULL on error.
 //
 // WARNING: `digest` must be the output of some hash function on the data to be
 // signed. Passing unhashed inputs will not result in a secure signature scheme.
 OPENSSL_EXPORT ECDSA_SIG *ECDSA_do_sign(const uint8_t *digest,
                                         size_t digest_len, const EC_KEY *key);

 // ECDSA_do_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.
 //
 // WARNING: `digest` must be the output of some hash function on the data to be
 // verified. Passing unhashed inputs will not result in a secure signature
 // scheme.
 OPENSSL_EXPORT int ECDSA_do_verify(const uint8_t *digest, size_t digest_len,
                                    const ECDSA_SIG *sig, const EC_KEY *key);


 // 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_bytes 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);


 // IEEE P1363 signing and verifying.
 //
 // ECDSA does not have a single, common signature format across all
 // applications. These functions implement the less common, fixed-width format,
 // defined in IEEE P1363. It is also used in PKCS#11 and DNSSEC. In it,
 // signatures are a concatenation of r and s components, each zero-padded up to
 // the width of the group order. This format is fixed-width, so a given ECDSA
 // curve's signatures will always have the same size.

 // ECDSA_sign_p1363 signs `digest_len` bytes from `digest` with `key` and writes
 // the resulting P1363-based signature to `sig`, which must have
 // `ECDSA_size_p1363(key)` bytes of space. On successful exit, `*out_sig_len` is
 // set to the actual number of bytes written, which will always match
 // `ECDSA_size_p1363(key)`. It returns one on success and zero otherwise.
 //
 // WARNING: `digest` must be the output of some hash function on the data to be
 // signed. Passing unhashed inputs will not result in a secure signature scheme.
 OPENSSL_EXPORT int ECDSA_sign_p1363(const uint8_t *digest, size_t digest_len,
                                     uint8_t *sig, size_t *out_sig_len,
                                     size_t max_sig_len, const EC_KEY *key);

 // ECDSA_verify_p1363 verifies that `sig_len` bytes from `sig` constitute a
 // valid P1363-based signature by `key` of `digest`. It returns one on success
 // or zero if the signature is invalid or an error occurred.
 //
 // WARNING: `digest` must be the output of some hash function on the data to be
 // verified. Passing unhashed inputs will not result in a secure signature
 // scheme.
 OPENSSL_EXPORT int ECDSA_verify_p1363(const uint8_t *digest, size_t digest_len,
                                       const uint8_t *sig, size_t sig_len,
                                       const EC_KEY *key);

 // ECDSA_size_p1363 returns the size of a P1363-based ECDSA signature using
 // `key`. It returns zero if `key` is NULL or if it doesn't have a group set.
 OPENSSL_EXPORT size_t ECDSA_size_p1363(const EC_KEY *key);


 // Testing-only functions.

 // ECDSA_sign_with_nonce_and_leak_private_key_for_testing behaves like
 // `ECDSA_do_sign` but uses `nonce` for the ECDSA nonce 'k', instead of a random
 // value. `nonce` is interpreted as a big-endian integer. It must be reduced
 // modulo the group order and padded with zeros up to `BN_num_bytes(order)`
 // bytes.
 //
 // WARNING: This function is only exported for testing purposes, when using test
 // vectors or fuzzing strategies. It must not be used outside tests and may leak
 // any private keys it is used with.
 OPENSSL_EXPORT ECDSA_SIG *
 ECDSA_sign_with_nonce_and_leak_private_key_for_testing(const uint8_t *digest,
                                                        size_t digest_len,
                                                        const EC_KEY *eckey,
                                                        const uint8_t *nonce,
                                                        size_t nonce_len);


 // Deprecated functions.

 // d2i_ECDSA_SIG parses aa DER-encoded ECDSA-Sig-Value structure from `len`
 // bytes at `*inp`, as described in `d2i_SAMPLE`.
 //
 // Use `ECDSA_SIG_parse` instead.
 OPENSSL_EXPORT ECDSA_SIG *d2i_ECDSA_SIG(ECDSA_SIG **out, const uint8_t **inp,
                                         long len);

 // i2d_ECDSA_SIG marshals `sig` as a DER-encoded ECDSA-Sig-Value, as described
 // in `i2d_SAMPLE`.
 //
 // Use `ECDSA_SIG_marshal` instead.
 OPENSSL_EXPORT int i2d_ECDSA_SIG(const ECDSA_SIG *sig, uint8_t **outp);


 #if defined(__cplusplus)
 }  // extern C

 extern "C++" {

 BSSL_NAMESPACE_BEGIN

 BORINGSSL_MAKE_DELETER(ECDSA_SIG, ECDSA_SIG_free)

 BSSL_NAMESPACE_END

 }  // 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
 #define ECDSA_R_TOO_MANY_ITERATIONS 106

 #endif  // OPENSSL_HEADER_ECDSA_H
	// Copyright 2002-2016 The OpenSSL Project Authors. All Rights Reserved.
	//
	// 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
	//
	// https://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.

	#ifndef OPENSSL_HEADER_ECDSA_H
	#define OPENSSL_HEADER_ECDSA_H

	#include <openssl/base.h> // IWYU pragma: export

	#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 verifying.
	//
	// ECDSA does not have a single, common signature format across all
	// applications. These functions implement the more common, ASN.1-based format.
	// In it, signatures are a DER-encoded ECDSA-Sig-Value structure. Note that this
	// format is variable-length. Callers must be prepared to receive signatures
	// that are slightly shorter than the maximum for the ECDSA curve.

	// ECDSA_sign signs `digest_len` bytes from `digest` with `key` and writes the
	// resulting ASN.1-based 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.
	//
	// WARNING: `digest` must be the output of some hash function on the data to be
	// signed. Passing unhashed inputs will not result in a secure signature scheme.
	OPENSSL_EXPORT int ECDSA_sign(int type, const uint8_t *digest,
	size_t digest_len, uint8_t *sig,
	unsigned int sig_len, const EC_KEY key);

	// ECDSA_verify verifies that `sig_len` bytes from `sig` constitute a valid
	// ASN.1-based 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 occurred.
	//
	// WARNING: `digest` must be the output of some hash function on the data to be
	// verified. Passing unhashed inputs will not result in a secure signature
	// scheme.
	OPENSSL_EXPORT int ECDSA_verify(int type, const uint8_t *digest,
	size_t digest_len, const uint8_t *sig,
	size_t sig_len, const EC_KEY *key);

	// ECDSA_size returns the maximum size of an ASN.1-based ECDSA signature using
	// `key`. It returns zero if `key` is NULL or if it doesn't have a group set.
	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_SIG_get0_r returns the r component of `sig`.
	OPENSSL_EXPORT const BIGNUM ECDSA_SIG_get0_r(const ECDSA_SIG sig);

	// ECDSA_SIG_get0_s returns the s component of `sig`.
	OPENSSL_EXPORT const BIGNUM ECDSA_SIG_get0_s(const ECDSA_SIG sig);

	// ECDSA_SIG_get0 sets `out_r` and `out_s`, if non-NULL, to the two
	// components of `sig`.
	OPENSSL_EXPORT void ECDSA_SIG_get0(const ECDSA_SIG sig, const BIGNUM *out_r,
	const BIGNUM **out_s);

	// ECDSA_SIG_set0 sets `sig`'s components to `r` and `s`, neither of which may
	// be NULL. On success, it takes ownership of each argument and returns one.
	// Otherwise, it returns zero.
	OPENSSL_EXPORT int ECDSA_SIG_set0(ECDSA_SIG sig, BIGNUM r, BIGNUM *s);

	// ECDSA_do_sign signs `digest_len` bytes from `digest` with `key` and returns
	// the resulting signature structure, or NULL on error.
	//
	// WARNING: `digest` must be the output of some hash function on the data to be
	// signed. Passing unhashed inputs will not result in a secure signature scheme.
	OPENSSL_EXPORT ECDSA_SIG ECDSA_do_sign(const uint8_t digest,
	size_t digest_len, const EC_KEY *key);

	// ECDSA_do_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.
	//
	// WARNING: `digest` must be the output of some hash function on the data to be
	// verified. Passing unhashed inputs will not result in a secure signature
	// scheme.
	OPENSSL_EXPORT int ECDSA_do_verify(const uint8_t *digest, size_t digest_len,
	const ECDSA_SIG sig, const EC_KEY key);


	// 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_bytes 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);


	// IEEE P1363 signing and verifying.
	//
	// ECDSA does not have a single, common signature format across all
	// applications. These functions implement the less common, fixed-width format,
	// defined in IEEE P1363. It is also used in PKCS#11 and DNSSEC. In it,
	// signatures are a concatenation of r and s components, each zero-padded up to
	// the width of the group order. This format is fixed-width, so a given ECDSA
	// curve's signatures will always have the same size.

	// ECDSA_sign_p1363 signs `digest_len` bytes from `digest` with `key` and writes
	// the resulting P1363-based signature to `sig`, which must have
	// `ECDSA_size_p1363(key)` bytes of space. On successful exit, `*out_sig_len` is
	// set to the actual number of bytes written, which will always match
	// `ECDSA_size_p1363(key)`. It returns one on success and zero otherwise.
	//
	// WARNING: `digest` must be the output of some hash function on the data to be
	// signed. Passing unhashed inputs will not result in a secure signature scheme.
	OPENSSL_EXPORT int ECDSA_sign_p1363(const uint8_t *digest, size_t digest_len,
	uint8_t sig, size_t out_sig_len,
	size_t max_sig_len, const EC_KEY *key);

	// ECDSA_verify_p1363 verifies that `sig_len` bytes from `sig` constitute a
	// valid P1363-based signature by `key` of `digest`. It returns one on success
	// or zero if the signature is invalid or an error occurred.
	//
	// WARNING: `digest` must be the output of some hash function on the data to be
	// verified. Passing unhashed inputs will not result in a secure signature
	// scheme.
	OPENSSL_EXPORT int ECDSA_verify_p1363(const uint8_t *digest, size_t digest_len,
	const uint8_t *sig, size_t sig_len,
	const EC_KEY *key);

	// ECDSA_size_p1363 returns the size of a P1363-based ECDSA signature using
	// `key`. It returns zero if `key` is NULL or if it doesn't have a group set.
	OPENSSL_EXPORT size_t ECDSA_size_p1363(const EC_KEY *key);


	// Testing-only functions.

	// ECDSA_sign_with_nonce_and_leak_private_key_for_testing behaves like
	// `ECDSA_do_sign` but uses `nonce` for the ECDSA nonce 'k', instead of a random
	// value. `nonce` is interpreted as a big-endian integer. It must be reduced
	// modulo the group order and padded with zeros up to `BN_num_bytes(order)`
	// bytes.
	//
	// WARNING: This function is only exported for testing purposes, when using test
	// vectors or fuzzing strategies. It must not be used outside tests and may leak
	// any private keys it is used with.
	OPENSSL_EXPORT ECDSA_SIG *
	ECDSA_sign_with_nonce_and_leak_private_key_for_testing(const uint8_t *digest,
	size_t digest_len,
	const EC_KEY *eckey,
	const uint8_t *nonce,
	size_t nonce_len);


	// Deprecated functions.

	// d2i_ECDSA_SIG parses aa DER-encoded ECDSA-Sig-Value structure from `len`
	// bytes at `*inp`, as described in `d2i_SAMPLE`.
	//
	// Use `ECDSA_SIG_parse` instead.
	OPENSSL_EXPORT ECDSA_SIG d2i_ECDSA_SIG(ECDSA_SIG out, const uint8_t *inp,
	long len);

	// i2d_ECDSA_SIG marshals `sig` as a DER-encoded ECDSA-Sig-Value, as described
	// in `i2d_SAMPLE`.
	//
	// Use `ECDSA_SIG_marshal` instead.
	OPENSSL_EXPORT int i2d_ECDSA_SIG(const ECDSA_SIG sig, uint8_t *outp);


	#if defined(__cplusplus)
	} // extern C

	extern "C++" {

	BSSL_NAMESPACE_BEGIN

	BORINGSSL_MAKE_DELETER(ECDSA_SIG, ECDSA_SIG_free)

	BSSL_NAMESPACE_END

	} // 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
	#define ECDSA_R_TOO_MANY_ITERATIONS 106

	#endif // OPENSSL_HEADER_ECDSA_H