1EC_KEY_NEW(3ossl) OpenSSL EC_KEY_NEW(3ossl)
2
6 EVP_EC_gen, EC_KEY_get_method, EC_KEY_set_method, EC_KEY_new_ex,
7 EC_KEY_new, EC_KEY_get_flags, EC_KEY_set_flags, EC_KEY_clear_flags,
8 EC_KEY_new_by_curve_name_ex, EC_KEY_new_by_curve_name, EC_KEY_free,
9 EC_KEY_copy, EC_KEY_dup, EC_KEY_up_ref, EC_KEY_get0_engine,
10 EC_KEY_get0_group, EC_KEY_set_group, EC_KEY_get0_private_key,
11 EC_KEY_set_private_key, EC_KEY_get0_public_key, EC_KEY_set_public_key,
12 EC_KEY_get_conv_form, EC_KEY_set_conv_form, EC_KEY_set_asn1_flag,
13 EC_KEY_decoded_from_explicit_params, EC_KEY_precompute_mult,
14 EC_KEY_generate_key, EC_KEY_check_key,
15 EC_KEY_set_public_key_affine_coordinates, EC_KEY_oct2key,
16 EC_KEY_key2buf, EC_KEY_oct2priv, EC_KEY_priv2oct, EC_KEY_priv2buf -
17 Functions for creating, destroying and manipulating EC_KEY objects
18
20 #include <openssl/ec.h>
21 EVP_PKEY *EVP_EC_gen(const char *curve);
23 The following functions have been deprecated since OpenSSL 3.0, and can
25 be hidden entirely by defining OPENSSL_API_COMPAT with a suitable
26 version value, see openssl_user_macros(7):
27 EC_KEY *EC_KEY_new_ex(OSSL_LIB_CTX *ctx, const char *propq);
29 EC_KEY *EC_KEY_new(void);
30 int EC_KEY_get_flags(const EC_KEY *key);
31 void EC_KEY_set_flags(EC_KEY *key, int flags);
32 void EC_KEY_clear_flags(EC_KEY *key, int flags);
33 EC_KEY *EC_KEY_new_by_curve_name_ex(OSSL_LIB_CTX *ctx, const char *propq,
34 int nid);
35 EC_KEY *EC_KEY_new_by_curve_name(int nid);
36 void EC_KEY_free(EC_KEY *key);
37 EC_KEY *EC_KEY_copy(EC_KEY *dst, const EC_KEY *src);
38 EC_KEY *EC_KEY_dup(const EC_KEY *src);
39 int EC_KEY_up_ref(EC_KEY *key);
40 ENGINE *EC_KEY_get0_engine(const EC_KEY *eckey);
41 const EC_GROUP *EC_KEY_get0_group(const EC_KEY *key);
42 int EC_KEY_set_group(EC_KEY *key, const EC_GROUP *group);
43 const BIGNUM *EC_KEY_get0_private_key(const EC_KEY *key);
44 int EC_KEY_set_private_key(EC_KEY *key, const BIGNUM *priv_key);
45 const EC_POINT *EC_KEY_get0_public_key(const EC_KEY *key);
46 int EC_KEY_set_public_key(EC_KEY *key, const EC_POINT *pub);
47 point_conversion_form_t EC_KEY_get_conv_form(const EC_KEY *key);
48 void EC_KEY_set_conv_form(EC_KEY *eckey, point_conversion_form_t cform);
49 void EC_KEY_set_asn1_flag(EC_KEY *eckey, int asn1_flag);
50 int EC_KEY_decoded_from_explicit_params(const EC_KEY *key);
51 int EC_KEY_generate_key(EC_KEY *key);
52 int EC_KEY_check_key(const EC_KEY *key);
53 int EC_KEY_set_public_key_affine_coordinates(EC_KEY *key, BIGNUM *x, BIGNUM *y);
54 const EC_KEY_METHOD *EC_KEY_get_method(const EC_KEY *key);
55 int EC_KEY_set_method(EC_KEY *key, const EC_KEY_METHOD *meth);
56 int EC_KEY_oct2key(EC_KEY *eckey, const unsigned char *buf, size_t len, BN_CTX *ctx);
58 size_t EC_KEY_key2buf(const EC_KEY *eckey, point_conversion_form_t form,
59 unsigned char **pbuf, BN_CTX *ctx);
60 int EC_KEY_oct2priv(EC_KEY *eckey, const unsigned char *buf, size_t len);
62 size_t EC_KEY_priv2oct(const EC_KEY *eckey, unsigned char *buf, size_t len);
63 size_t EC_KEY_priv2buf(const EC_KEY *eckey, unsigned char **pbuf);
65 int EC_KEY_precompute_mult(EC_KEY *key, BN_CTX *ctx);
66
68 EVP_EC_gen() generates a new EC key pair on the given curve.
69 All of the functions described below are deprecated. Applications
71 should instead use EVP_EC_gen(), EVP_PKEY_Q_keygen(3), or
72 EVP_PKEY_keygen_init(3) and EVP_PKEY_keygen(3).
73 An EC_KEY represents a public key and, optionally, the associated
75 private key. A new EC_KEY with no associated curve can be constructed
76 by calling EC_KEY_new_ex() and specifying the associated library
77 context in ctx (see OSSL_LIB_CTX(3)) and property query string propq.
78 The ctx parameter may be NULL in which case the default library context
79 is used. The reference count for the newly created EC_KEY is initially
80 set to 1. A curve can be associated with the EC_KEY by calling
81 EC_KEY_set_group().
82 EC_KEY_new() is the same as EC_KEY_new_ex() except that the default
84 library context is always used.
85 Alternatively a new EC_KEY can be constructed by calling
87 EC_KEY_new_by_curve_name_ex() and supplying the nid of the associated
88 curve, the library context to be used ctx (see OSSL_LIB_CTX(3)) and any
89 property query string propq. The ctx parameter may be NULL in which
90 case the default library context is used. The propq value may also be
91 NULL. See EC_GROUP_new(3) for a description of curve names. This
92 function simply wraps calls to EC_KEY_new_ex() and
93 EC_GROUP_new_by_curve_name_ex().
94 EC_KEY_new_by_curve_name() is the same as EC_KEY_new_by_curve_name_ex()
96 except that the default library context is always used and a NULL
97 property query string.
98 Calling EC_KEY_free() decrements the reference count for the EC_KEY
100 object, and if it has dropped to zero then frees the memory associated
101 with it. If key is NULL nothing is done.
102 EC_KEY_copy() copies the contents of the EC_KEY in src into dest.
104 EC_KEY_dup() creates a new EC_KEY object and copies ec_key into it.
106 EC_KEY_up_ref() increments the reference count associated with the
108 EC_KEY object.
109 EC_KEY_get0_engine() returns a handle to the ENGINE that has been set
111 for this EC_KEY object.
112 EC_KEY_generate_key() generates a new public and private key for the
114 supplied eckey object. eckey must have an EC_GROUP object associated
115 with it before calling this function. The private key is a random
116 integer (0 < priv_key < order, where order is the order of the EC_GROUP
117 object). The public key is an EC_POINT on the curve calculated by
118 multiplying the generator for the curve by the private key.
119 EC_KEY_check_key() performs various sanity checks on the EC_KEY object
121 to confirm that it is valid.
122 EC_KEY_set_public_key_affine_coordinates() sets the public key for key
124 based on its affine coordinates; i.e., it constructs an EC_POINT object
125 based on the supplied x and y values and sets the public key to be this
126 EC_POINT. It also performs certain sanity checks on the key to confirm
127 that it is valid.
128 The functions EC_KEY_get0_group(), EC_KEY_set_group(),
130 EC_KEY_get0_private_key(), EC_KEY_set_private_key(),
131 EC_KEY_get0_public_key(), and EC_KEY_set_public_key() get and set the
132 EC_GROUP object, the private key, and the EC_POINT public key for the
133 key respectively. The function EC_KEY_set_private_key() accepts NULL as
134 the priv_key argument to securely clear the private key component from
135 the EC_KEY.
136 The functions EC_KEY_get_conv_form() and EC_KEY_set_conv_form() get and
138 set the point_conversion_form for the key. For a description of
139 point_conversion_forms please see EC_POINT_new(3).
140 EC_KEY_set_flags() sets the flags in the flags parameter on the EC_KEY
142 object. Any flags that are already set are left set. The flags
143 currently defined are EC_FLAG_NON_FIPS_ALLOW and EC_FLAG_FIPS_CHECKED.
144 In addition there is the flag EC_FLAG_COFACTOR_ECDH which is specific
145 to ECDH. EC_KEY_get_flags() returns the current flags that are set for
146 this EC_KEY. EC_KEY_clear_flags() clears the flags indicated by the
147 flags parameter; all other flags are left in their existing state.
148 EC_KEY_set_asn1_flag() sets the asn1_flag on the underlying EC_GROUP
150 object (if set). Refer to EC_GROUP_copy(3) for further information on
151 the asn1_flag.
152 EC_KEY_decoded_from_explicit_params() returns 1 if the group of the key
154 was decoded from data with explicitly encoded group parameters, -1 if
155 the key is NULL or the group parameters are missing, and 0 otherwise.
156 EC_KEY_precompute_mult() stores multiples of the underlying EC_GROUP
158 generator for faster point multiplication. See also EC_POINT_add(3).
159 Modern versions should instead switch to named curves which OpenSSL has
160 hardcoded lookup tables for.
161 EC_KEY_oct2key() and EC_KEY_key2buf() are identical to the functions
163 EC_POINT_oct2point() and EC_POINT_point2buf() except they use the
164 public key EC_POINT in eckey.
165 EC_KEY_oct2priv() and EC_KEY_priv2oct() convert between the private key
167 component of eckey and octet form. The octet form consists of the
168 content octets of the privateKey OCTET STRING in an ECPrivateKey ASN.1
169 structure.
170 The function EC_KEY_priv2oct() must be supplied with a buffer long
172 enough to store the octet form. The return value provides the number of
173 octets stored. Calling the function with a NULL buffer will not
174 perform the conversion but will just return the required buffer length.
175 The function EC_KEY_priv2buf() allocates a buffer of suitable length
177 and writes an EC_KEY to it in octet format. The allocated buffer is
178 written to *pbuf and its length is returned. The caller must free up
179 the allocated buffer with a call to OPENSSL_free(). Since the allocated
180 buffer value is written to *pbuf the pbuf parameter MUST NOT be NULL.
181 EC_KEY_priv2buf() converts an EC_KEY private key into an allocated
183 buffer.
184
186 EC_KEY_new_ex(), EC_KEY_new(), EC_KEY_new_by_curve_name_ex(),
187 EC_KEY_new_by_curve_name() and EC_KEY_dup() return a pointer to the
188 newly created EC_KEY object, or NULL on error.
189 EC_KEY_get_flags() returns the flags associated with the EC_KEY object
191 as an integer.
192 EC_KEY_copy() returns a pointer to the destination key, or NULL on
194 error.
195 EC_KEY_get0_engine() returns a pointer to an ENGINE, or NULL if it
197 wasn't set.
198 EC_KEY_up_ref(), EC_KEY_set_group(), EC_KEY_set_public_key(),
200 EC_KEY_precompute_mult(), EC_KEY_generate_key(), EC_KEY_check_key(),
201 EC_KEY_set_public_key_affine_coordinates(), EC_KEY_oct2key() and
202 EC_KEY_oct2priv() return 1 on success or 0 on error.
203 EC_KEY_set_private_key() returns 1 on success or 0 on error except when
205 the priv_key argument is NULL, in that case it returns 0, for legacy
206 compatibility, and should not be treated as an error.
207 EC_KEY_get0_group() returns the EC_GROUP associated with the EC_KEY.
209 EC_KEY_get0_private_key() returns the private key associated with the
211 EC_KEY.
212 EC_KEY_get_conv_form() return the point_conversion_form for the EC_KEY.
214 EC_KEY_key2buf(), EC_KEY_priv2oct() and EC_KEY_priv2buf() return the
216 length of the buffer or 0 on error.
217
219 EVP_PKEY_Q_keygen(3) crypto(7), EC_GROUP_new(3), EC_GROUP_copy(3),
220 EC_POINT_new(3), EC_POINT_add(3), EC_GFp_simple_method(3),
221 d2i_ECPKParameters(3), OSSL_LIB_CTX(3)
222
224 EVP_EC_gen() was added in OpenSSL 3.0. All other functions described
225 here were deprecated in OpenSSL 3.0. For replacement see
226 EVP_PKEY-EC(7).
227
229 Copyright 2013-2023 The OpenSSL Project Authors. All Rights Reserved.
230 Licensed under the Apache License 2.0 (the "License"). You may not use
232 this file except in compliance with the License. You can obtain a copy
233 in the file LICENSE in the source distribution or at
234 <https://www.openssl.org/source/license.html>.
2353.1.1 2023-08-31 EC_KEY_NEW(3ossl)