1/* ====================================================================
2 * Copyright (c) 1998-2005 The OpenSSL Project. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 *
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 *
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in
13 * the documentation and/or other materials provided with the
14 * distribution.
15 *
16 * 3. All advertising materials mentioning features or use of this
17 * software must display the following acknowledgment:
18 * "This product includes software developed by the OpenSSL Project
19 * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
20 *
21 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
22 * endorse or promote products derived from this software without
23 * prior written permission. For written permission, please contact
24 * openssl-core@OpenSSL.org.
25 *
26 * 5. Products derived from this software may not be called "OpenSSL"
27 * nor may "OpenSSL" appear in their names without prior written
28 * permission of the OpenSSL Project.
29 *
30 * 6. Redistributions of any form whatsoever must retain the following
31 * acknowledgment:
32 * "This product includes software developed by the OpenSSL Project
33 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
34 *
35 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
36 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
37 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
38 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
39 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
40 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
41 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
42 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
43 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
44 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
45 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
46 * OF THE POSSIBILITY OF SUCH DAMAGE.
47 * ====================================================================
48 *
49 * This product includes cryptographic software written by Eric Young
50 * (eay@cryptsoft.com). This product includes software written by Tim
51 * Hudson (tjh@cryptsoft.com). */
52
53#ifndef OPENSSL_HEADER_ECDSA_H
54#define OPENSSL_HEADER_ECDSA_H
55
56#include <openssl/base.h>
57
58#include <openssl/ec_key.h>
59
60#if defined(__cplusplus)
61extern "C" {
62#endif
63
64
65// ECDSA contains functions for signing and verifying with the Digital Signature
66// Algorithm over elliptic curves.
67
68
69// Signing and verifying.
70
71// ECDSA_sign signs |digest_len| bytes from |digest| with |key| and writes the
72// resulting signature to |sig|, which must have |ECDSA_size(key)| bytes of
73// space. On successful exit, |*sig_len| is set to the actual number of bytes
74// written. The |type| argument should be zero. It returns one on success and
75// zero otherwise.
76OPENSSL_EXPORT int ECDSA_sign(int type, const uint8_t *digest,
77 size_t digest_len, uint8_t *sig,
78 unsigned int *sig_len, const EC_KEY *key);
79
80// ECDSA_verify verifies that |sig_len| bytes from |sig| constitute a valid
81// signature by |key| of |digest|. (The |type| argument should be zero.) It
82// returns one on success or zero if the signature is invalid or an error
83// occurred.
84OPENSSL_EXPORT int ECDSA_verify(int type, const uint8_t *digest,
85 size_t digest_len, const uint8_t *sig,
86 size_t sig_len, const EC_KEY *key);
87
88// ECDSA_size returns the maximum size of an ECDSA signature using |key|. It
89// returns zero if |key| is NULL or if it doesn't have a group set.
90OPENSSL_EXPORT size_t ECDSA_size(const EC_KEY *key);
91
92
93// Low-level signing and verification.
94//
95// Low-level functions handle signatures as |ECDSA_SIG| structures which allow
96// the two values in an ECDSA signature to be handled separately.
97
98struct ecdsa_sig_st {
99 BIGNUM *r;
100 BIGNUM *s;
101};
102
103// ECDSA_SIG_new returns a fresh |ECDSA_SIG| structure or NULL on error.
104OPENSSL_EXPORT ECDSA_SIG *ECDSA_SIG_new(void);
105
106// ECDSA_SIG_free frees |sig| its member |BIGNUM|s.
107OPENSSL_EXPORT void ECDSA_SIG_free(ECDSA_SIG *sig);
108
109// ECDSA_SIG_get0 sets |*out_r| and |*out_s|, if non-NULL, to the two
110// components of |sig|.
111OPENSSL_EXPORT void ECDSA_SIG_get0(const ECDSA_SIG *sig, const BIGNUM **out_r,
112 const BIGNUM **out_s);
113
114// ECDSA_SIG_set0 sets |sig|'s components to |r| and |s|, neither of which may
115// be NULL. On success, it takes ownership of each argument and returns one.
116// Otherwise, it returns zero.
117OPENSSL_EXPORT int ECDSA_SIG_set0(ECDSA_SIG *sig, BIGNUM *r, BIGNUM *s);
118
119// ECDSA_do_sign signs |digest_len| bytes from |digest| with |key| and returns
120// the resulting signature structure, or NULL on error.
121OPENSSL_EXPORT ECDSA_SIG *ECDSA_do_sign(const uint8_t *digest,
122 size_t digest_len, const EC_KEY *key);
123
124// ECDSA_do_verify verifies that |sig| constitutes a valid signature by |key|
125// of |digest|. It returns one on success or zero if the signature is invalid
126// or on error.
127OPENSSL_EXPORT int ECDSA_do_verify(const uint8_t *digest, size_t digest_len,
128 const ECDSA_SIG *sig, const EC_KEY *key);
129
130
131// ASN.1 functions.
132
133// ECDSA_SIG_parse parses a DER-encoded ECDSA-Sig-Value structure from |cbs| and
134// advances |cbs|. It returns a newly-allocated |ECDSA_SIG| or NULL on error.
135OPENSSL_EXPORT ECDSA_SIG *ECDSA_SIG_parse(CBS *cbs);
136
137// ECDSA_SIG_from_bytes parses |in| as a DER-encoded ECDSA-Sig-Value structure.
138// It returns a newly-allocated |ECDSA_SIG| structure or NULL on error.
139OPENSSL_EXPORT ECDSA_SIG *ECDSA_SIG_from_bytes(const uint8_t *in,
140 size_t in_len);
141
142// ECDSA_SIG_marshal marshals |sig| as a DER-encoded ECDSA-Sig-Value and appends
143// the result to |cbb|. It returns one on success and zero on error.
144OPENSSL_EXPORT int ECDSA_SIG_marshal(CBB *cbb, const ECDSA_SIG *sig);
145
146// ECDSA_SIG_to_bytes marshals |sig| as a DER-encoded ECDSA-Sig-Value and, on
147// success, sets |*out_bytes| to a newly allocated buffer containing the result
148// and returns one. Otherwise, it returns zero. The result should be freed with
149// |OPENSSL_free|.
150OPENSSL_EXPORT int ECDSA_SIG_to_bytes(uint8_t **out_bytes, size_t *out_len,
151 const ECDSA_SIG *sig);
152
153// ECDSA_SIG_max_len returns the maximum length of a DER-encoded ECDSA-Sig-Value
154// structure for a group whose order is represented in |order_len| bytes, or
155// zero on overflow.
156OPENSSL_EXPORT size_t ECDSA_SIG_max_len(size_t order_len);
157
158
159// Deprecated functions.
160
161// d2i_ECDSA_SIG parses an ASN.1, DER-encoded, signature from |len| bytes at
162// |*inp|. If |out| is not NULL then, on exit, a pointer to the result is in
163// |*out|. Note that, even if |*out| is already non-NULL on entry, it will not
164// be written to. Rather, a fresh |ECDSA_SIG| is allocated and the previous one
165// is freed. On successful exit, |*inp| is advanced past the DER structure. It
166// returns the result or NULL on error.
167OPENSSL_EXPORT ECDSA_SIG *d2i_ECDSA_SIG(ECDSA_SIG **out, const uint8_t **inp,
168 long len);
169
170// i2d_ECDSA_SIG marshals a signature from |sig| to an ASN.1, DER
171// structure. If |outp| is not NULL then the result is written to |*outp| and
172// |*outp| is advanced just past the output. It returns the number of bytes in
173// the result, whether written or not, or a negative value on error.
174OPENSSL_EXPORT int i2d_ECDSA_SIG(const ECDSA_SIG *sig, uint8_t **outp);
175
176
177#if defined(__cplusplus)
178} // extern C
179
180extern "C++" {
181
182BSSL_NAMESPACE_BEGIN
183
184BORINGSSL_MAKE_DELETER(ECDSA_SIG, ECDSA_SIG_free)
185
186BSSL_NAMESPACE_END
187
188} // extern C++
189
190#endif
191
192#define ECDSA_R_BAD_SIGNATURE 100
193#define ECDSA_R_MISSING_PARAMETERS 101
194#define ECDSA_R_NEED_NEW_SETUP_VALUES 102
195#define ECDSA_R_NOT_IMPLEMENTED 103
196#define ECDSA_R_RANDOM_NUMBER_GENERATION_FAILED 104
197#define ECDSA_R_ENCODE_ERROR 105
198
199#endif // OPENSSL_HEADER_ECDSA_H
200