gnunet-android

GNUnet for Android
Log | Files | Refs | README

ec_key.h (15646B)


      1 // Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved.
      2 // Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved.
      3 //
      4 // Licensed under the Apache License, Version 2.0 (the "License");
      5 // you may not use this file except in compliance with the License.
      6 // You may obtain a copy of the License at
      7 //
      8 //     https://www.apache.org/licenses/LICENSE-2.0
      9 //
     10 // Unless required by applicable law or agreed to in writing, software
     11 // distributed under the License is distributed on an "AS IS" BASIS,
     12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13 // See the License for the specific language governing permissions and
     14 // limitations under the License.
     15 
     16 #ifndef OPENSSL_HEADER_EC_KEY_H
     17 #define OPENSSL_HEADER_EC_KEY_H
     18 
     19 #include <openssl/base.h>   // IWYU pragma: export
     20 
     21 #include <openssl/ec.h>
     22 #include <openssl/engine.h>
     23 #include <openssl/ex_data.h>
     24 
     25 #if defined(__cplusplus)
     26 extern "C" {
     27 #endif
     28 
     29 
     30 // ec_key.h contains functions that handle elliptic-curve points that are
     31 // public/private keys.
     32 
     33 
     34 // EC key objects.
     35 //
     36 // An |EC_KEY| object represents a public or private EC key. A given object may
     37 // be used concurrently on multiple threads by non-mutating functions, provided
     38 // no other thread is concurrently calling a mutating function. Unless otherwise
     39 // documented, functions which take a |const| pointer are non-mutating and
     40 // functions which take a non-|const| pointer are mutating.
     41 
     42 // EC_KEY_new returns a fresh |EC_KEY| object or NULL on error.
     43 OPENSSL_EXPORT EC_KEY *EC_KEY_new(void);
     44 
     45 // EC_KEY_new_method acts the same as |EC_KEY_new|, but takes an explicit
     46 // |ENGINE|.
     47 OPENSSL_EXPORT EC_KEY *EC_KEY_new_method(const ENGINE *engine);
     48 
     49 // EC_KEY_new_by_curve_name returns a fresh EC_KEY for group specified by |nid|
     50 // or NULL on error.
     51 OPENSSL_EXPORT EC_KEY *EC_KEY_new_by_curve_name(int nid);
     52 
     53 // EC_KEY_free frees all the data owned by |key| and |key| itself.
     54 OPENSSL_EXPORT void EC_KEY_free(EC_KEY *key);
     55 
     56 // EC_KEY_dup returns a fresh copy of |src| or NULL on error.
     57 OPENSSL_EXPORT EC_KEY *EC_KEY_dup(const EC_KEY *src);
     58 
     59 // EC_KEY_up_ref increases the reference count of |key| and returns one. It does
     60 // not mutate |key| for thread-safety purposes and may be used concurrently.
     61 OPENSSL_EXPORT int EC_KEY_up_ref(EC_KEY *key);
     62 
     63 // EC_KEY_is_opaque returns one if |key| is opaque and doesn't expose its key
     64 // material. Otherwise it return zero.
     65 OPENSSL_EXPORT int EC_KEY_is_opaque(const EC_KEY *key);
     66 
     67 // EC_KEY_get0_group returns a pointer to the |EC_GROUP| object inside |key|.
     68 OPENSSL_EXPORT const EC_GROUP *EC_KEY_get0_group(const EC_KEY *key);
     69 
     70 // EC_KEY_set_group sets the |EC_GROUP| object that |key| will use to |group|.
     71 // It returns one on success and zero if |key| is already configured with a
     72 // different group.
     73 OPENSSL_EXPORT int EC_KEY_set_group(EC_KEY *key, const EC_GROUP *group);
     74 
     75 // EC_KEY_get0_private_key returns a pointer to the private key inside |key|.
     76 OPENSSL_EXPORT const BIGNUM *EC_KEY_get0_private_key(const EC_KEY *key);
     77 
     78 // EC_KEY_set_private_key sets the private key of |key| to |priv|. It returns
     79 // one on success and zero otherwise. |key| must already have had a group
     80 // configured (see |EC_KEY_set_group| and |EC_KEY_new_by_curve_name|).
     81 OPENSSL_EXPORT int EC_KEY_set_private_key(EC_KEY *key, const BIGNUM *priv);
     82 
     83 // EC_KEY_get0_public_key returns a pointer to the public key point inside
     84 // |key|.
     85 OPENSSL_EXPORT const EC_POINT *EC_KEY_get0_public_key(const EC_KEY *key);
     86 
     87 // EC_KEY_set_public_key sets the public key of |key| to |pub|, by copying it.
     88 // It returns one on success and zero otherwise. |key| must already have had a
     89 // group configured (see |EC_KEY_set_group| and |EC_KEY_new_by_curve_name|), and
     90 // |pub| must also belong to that group.
     91 OPENSSL_EXPORT int EC_KEY_set_public_key(EC_KEY *key, const EC_POINT *pub);
     92 
     93 #define EC_PKEY_NO_PARAMETERS 0x001
     94 #define EC_PKEY_NO_PUBKEY 0x002
     95 
     96 // EC_KEY_get_enc_flags returns the encoding flags for |key|, which is a
     97 // bitwise-OR of |EC_PKEY_*| values.
     98 OPENSSL_EXPORT unsigned EC_KEY_get_enc_flags(const EC_KEY *key);
     99 
    100 // EC_KEY_set_enc_flags sets the encoding flags for |key|, which is a
    101 // bitwise-OR of |EC_PKEY_*| values.
    102 OPENSSL_EXPORT void EC_KEY_set_enc_flags(EC_KEY *key, unsigned flags);
    103 
    104 // EC_KEY_get_conv_form returns the conversation form that will be used by
    105 // |key|.
    106 OPENSSL_EXPORT point_conversion_form_t EC_KEY_get_conv_form(const EC_KEY *key);
    107 
    108 // EC_KEY_set_conv_form sets the conversion form to be used by |key|.
    109 OPENSSL_EXPORT void EC_KEY_set_conv_form(EC_KEY *key,
    110                                          point_conversion_form_t cform);
    111 
    112 // EC_KEY_check_key performs several checks on |key| (possibly including an
    113 // expensive check that the public key is in the primary subgroup). It returns
    114 // one if all checks pass and zero otherwise. If it returns zero then detail
    115 // about the problem can be found on the error stack.
    116 OPENSSL_EXPORT int EC_KEY_check_key(const EC_KEY *key);
    117 
    118 // EC_KEY_check_fips performs both a signing pairwise consistency test
    119 // (FIPS 140-2 4.9.2) and the consistency test from SP 800-56Ar3 section
    120 // 5.6.2.1.4. It returns one if it passes and zero otherwise.
    121 OPENSSL_EXPORT int EC_KEY_check_fips(const EC_KEY *key);
    122 
    123 // EC_KEY_set_public_key_affine_coordinates sets the public key in |key| to
    124 // (|x|, |y|). It returns one on success and zero on error. It's considered an
    125 // error if |x| and |y| do not represent a point on |key|'s curve.
    126 OPENSSL_EXPORT int EC_KEY_set_public_key_affine_coordinates(EC_KEY *key,
    127                                                             const BIGNUM *x,
    128                                                             const BIGNUM *y);
    129 
    130 // EC_KEY_oct2key decodes |len| bytes from |in| as an EC public key in X9.62
    131 // form. |key| must already have a group configured. On success, it sets the
    132 // public key in |key| to the result and returns one. Otherwise, it returns
    133 // zero.
    134 OPENSSL_EXPORT int EC_KEY_oct2key(EC_KEY *key, const uint8_t *in, size_t len,
    135                                   BN_CTX *ctx);
    136 
    137 // EC_KEY_key2buf behaves like |EC_POINT_point2buf|, except it encodes the
    138 // public key in |key|.
    139 OPENSSL_EXPORT size_t EC_KEY_key2buf(const EC_KEY *key,
    140                                      point_conversion_form_t form,
    141                                      uint8_t **out_buf, BN_CTX *ctx);
    142 
    143 // EC_KEY_oct2priv decodes a big-endian, zero-padded integer from |len| bytes
    144 // from |in| and sets |key|'s private key to the result. It returns one on
    145 // success and zero on error. The input must be padded to the size of |key|'s
    146 // group order.
    147 OPENSSL_EXPORT int EC_KEY_oct2priv(EC_KEY *key, const uint8_t *in, size_t len);
    148 
    149 // EC_KEY_priv2oct serializes |key|'s private key as a big-endian integer,
    150 // zero-padded to the size of |key|'s group order and writes the result to at
    151 // most |max_out| bytes of |out|. It returns the number of bytes written on
    152 // success and zero on error. If |out| is NULL, it returns the number of bytes
    153 // needed without writing anything.
    154 OPENSSL_EXPORT size_t EC_KEY_priv2oct(const EC_KEY *key, uint8_t *out,
    155                                       size_t max_out);
    156 
    157 // EC_KEY_priv2buf behaves like |EC_KEY_priv2oct| but sets |*out_buf| to a
    158 // newly-allocated buffer containing the result. It returns the size of the
    159 // result on success and zero on error. The caller must release |*out_buf| with
    160 // |OPENSSL_free| when done.
    161 OPENSSL_EXPORT size_t EC_KEY_priv2buf(const EC_KEY *key, uint8_t **out_buf);
    162 
    163 
    164 // Key generation.
    165 
    166 // EC_KEY_generate_key generates a random, private key, calculates the
    167 // corresponding public key and stores both in |key|. It returns one on success
    168 // or zero otherwise.
    169 OPENSSL_EXPORT int EC_KEY_generate_key(EC_KEY *key);
    170 
    171 // EC_KEY_generate_key_fips behaves like |EC_KEY_generate_key| but performs
    172 // additional checks for FIPS compliance. This function is applicable when
    173 // generating keys for either signing/verification or key agreement because
    174 // both types of consistency check (PCT) are performed.
    175 OPENSSL_EXPORT int EC_KEY_generate_key_fips(EC_KEY *key);
    176 
    177 // EC_KEY_derive_from_secret deterministically derives a private key for |group|
    178 // from an input secret using HKDF-SHA256. It returns a newly-allocated |EC_KEY|
    179 // on success or NULL on error. |secret| must not be used in any other
    180 // algorithm. If using a base secret for multiple operations, derive separate
    181 // values with a KDF such as HKDF first.
    182 //
    183 // Note this function implements an arbitrary derivation scheme, rather than any
    184 // particular standard one. New protocols are recommended to use X25519 and
    185 // Ed25519, which have standard byte import functions. See
    186 // |X25519_public_from_private| and |ED25519_keypair_from_seed|.
    187 OPENSSL_EXPORT EC_KEY *EC_KEY_derive_from_secret(const EC_GROUP *group,
    188                                                  const uint8_t *secret,
    189                                                  size_t secret_len);
    190 
    191 
    192 // Serialisation.
    193 
    194 // EC_KEY_parse_private_key parses a DER-encoded ECPrivateKey structure (RFC
    195 // 5915) from |cbs| and advances |cbs|. It returns a newly-allocated |EC_KEY| or
    196 // NULL on error. If |group| is non-null, the parameters field of the
    197 // ECPrivateKey may be omitted (but must match |group| if present). Otherwise,
    198 // the parameters field is required.
    199 OPENSSL_EXPORT EC_KEY *EC_KEY_parse_private_key(CBS *cbs,
    200                                                 const EC_GROUP *group);
    201 
    202 // EC_KEY_marshal_private_key marshals |key| as a DER-encoded ECPrivateKey
    203 // structure (RFC 5915) and appends the result to |cbb|. It returns one on
    204 // success and zero on failure. |enc_flags| is a combination of |EC_PKEY_*|
    205 // values and controls whether corresponding fields are omitted.
    206 OPENSSL_EXPORT int EC_KEY_marshal_private_key(CBB *cbb, const EC_KEY *key,
    207                                               unsigned enc_flags);
    208 
    209 // EC_KEY_parse_curve_name parses a DER-encoded OBJECT IDENTIFIER as a curve
    210 // name from |cbs| and advances |cbs|. It returns the decoded |EC_GROUP| or NULL
    211 // on error.
    212 //
    213 // This function returns a non-const pointer which may be passed to
    214 // |EC_GROUP_free|. However, the resulting object is actually static and calling
    215 // |EC_GROUP_free| is optional.
    216 //
    217 // TODO(davidben): Make this return a const pointer, if it does not break too
    218 // many callers.
    219 OPENSSL_EXPORT EC_GROUP *EC_KEY_parse_curve_name(CBS *cbs);
    220 
    221 // EC_KEY_marshal_curve_name marshals |group| as a DER-encoded OBJECT IDENTIFIER
    222 // and appends the result to |cbb|. It returns one on success and zero on
    223 // failure.
    224 OPENSSL_EXPORT int EC_KEY_marshal_curve_name(CBB *cbb, const EC_GROUP *group);
    225 
    226 // EC_KEY_parse_parameters parses a DER-encoded ECParameters structure (RFC
    227 // 5480) from |cbs| and advances |cbs|. It returns the resulting |EC_GROUP| or
    228 // NULL on error. It supports the namedCurve and specifiedCurve options, but use
    229 // of specifiedCurve is deprecated. Use |EC_KEY_parse_curve_name| instead.
    230 //
    231 // This function returns a non-const pointer which may be passed to
    232 // |EC_GROUP_free|. However, the resulting object is actually static and calling
    233 // |EC_GROUP_free| is optional.
    234 //
    235 // TODO(davidben): Make this return a const pointer, if it does not break too
    236 // many callers.
    237 OPENSSL_EXPORT EC_GROUP *EC_KEY_parse_parameters(CBS *cbs);
    238 
    239 
    240 // ex_data functions.
    241 //
    242 // These functions are wrappers. See |ex_data.h| for details.
    243 
    244 OPENSSL_EXPORT int EC_KEY_get_ex_new_index(long argl, void *argp,
    245                                            CRYPTO_EX_unused *unused,
    246                                            CRYPTO_EX_dup *dup_unused,
    247                                            CRYPTO_EX_free *free_func);
    248 OPENSSL_EXPORT int EC_KEY_set_ex_data(EC_KEY *r, int idx, void *arg);
    249 OPENSSL_EXPORT void *EC_KEY_get_ex_data(const EC_KEY *r, int idx);
    250 
    251 
    252 // ECDSA method.
    253 
    254 // ECDSA_FLAG_OPAQUE specifies that this ECDSA_METHOD does not expose its key
    255 // material. This may be set if, for instance, it is wrapping some other crypto
    256 // API, like a platform key store.
    257 #define ECDSA_FLAG_OPAQUE 1
    258 
    259 // ecdsa_method_st is a structure of function pointers for implementing ECDSA.
    260 // See engine.h.
    261 struct ecdsa_method_st {
    262   struct openssl_method_common_st common;
    263 
    264   void *app_data;
    265 
    266   int (*init)(EC_KEY *key);
    267   int (*finish)(EC_KEY *key);
    268 
    269   // sign matches the arguments and behaviour of |ECDSA_sign|.
    270   int (*sign)(const uint8_t *digest, size_t digest_len, uint8_t *sig,
    271               unsigned int *sig_len, EC_KEY *eckey);
    272 
    273   int flags;
    274 };
    275 
    276 
    277 // Deprecated functions.
    278 
    279 // EC_KEY_set_asn1_flag does nothing.
    280 OPENSSL_EXPORT void EC_KEY_set_asn1_flag(EC_KEY *key, int flag);
    281 
    282 // d2i_ECPrivateKey parses a DER-encoded ECPrivateKey structure (RFC 5915) from
    283 // |len| bytes at |*inp|, as described in |d2i_SAMPLE|. On input, if |*out_key|
    284 // is non-NULL and has a group configured, the parameters field may be omitted
    285 // but must match that group if present.
    286 //
    287 // Use |EC_KEY_parse_private_key| instead.
    288 OPENSSL_EXPORT EC_KEY *d2i_ECPrivateKey(EC_KEY **out_key, const uint8_t **inp,
    289                                         long len);
    290 
    291 // i2d_ECPrivateKey marshals |key| as a DER-encoded ECPrivateKey structure (RFC
    292 // 5915), as described in |i2d_SAMPLE|.
    293 //
    294 // Use |EC_KEY_marshal_private_key| instead.
    295 OPENSSL_EXPORT int i2d_ECPrivateKey(const EC_KEY *key, uint8_t **outp);
    296 
    297 // d2i_ECPKParameters parses a DER-encoded ECParameters structure (RFC 5480)
    298 // from |len| bytes at |*inp|, as described in |d2i_SAMPLE|. For legacy reasons,
    299 // it recognizes the specifiedCurve form, but only for curves that are already
    300 // supported as named curves.
    301 //
    302 // Use |EC_KEY_parse_parameters| or |EC_KEY_parse_curve_name| instead.
    303 OPENSSL_EXPORT EC_GROUP *d2i_ECPKParameters(EC_GROUP **out, const uint8_t **inp,
    304                                             long len);
    305 
    306 // i2d_ECPKParameters marshals |group| as a DER-encoded ECParameters structure
    307 // (RFC 5480), as described in |i2d_SAMPLE|.
    308 //
    309 // Use |EC_KEY_marshal_curve_name| instead.
    310 OPENSSL_EXPORT int i2d_ECPKParameters(const EC_GROUP *group, uint8_t **outp);
    311 
    312 // d2i_ECParameters parses a DER-encoded ECParameters structure (RFC 5480) from
    313 // |len| bytes at |*inp|, as described in |d2i_SAMPLE|. It returns the result as
    314 // an |EC_KEY| with parameters, but no key, configured.
    315 //
    316 // Use |EC_KEY_parse_parameters| or |EC_KEY_parse_curve_name| instead.
    317 OPENSSL_EXPORT EC_KEY *d2i_ECParameters(EC_KEY **out_key, const uint8_t **inp,
    318                                         long len);
    319 
    320 // i2d_ECParameters marshals |key|'s parameters as a DER-encoded OBJECT
    321 // IDENTIFIER, as described in |i2d_SAMPLE|.
    322 //
    323 // Use |EC_KEY_marshal_curve_name| instead.
    324 OPENSSL_EXPORT int i2d_ECParameters(const EC_KEY *key, uint8_t **outp);
    325 
    326 // o2i_ECPublicKey parses an EC point from |len| bytes at |*inp| into
    327 // |*out_key|. Note that this differs from the d2i format in that |*out_key|
    328 // must be non-NULL with a group set. On successful exit, |*inp| is advanced by
    329 // |len| bytes. It returns |*out_key| or NULL on error.
    330 //
    331 // Use |EC_POINT_oct2point| instead.
    332 OPENSSL_EXPORT EC_KEY *o2i_ECPublicKey(EC_KEY **out_key, const uint8_t **inp,
    333                                        long len);
    334 
    335 // i2o_ECPublicKey marshals an EC point from |key|, as described in
    336 // |i2d_SAMPLE|, except it returns zero on error instead of a negative value.
    337 //
    338 // Use |EC_POINT_point2cbb| instead.
    339 OPENSSL_EXPORT int i2o_ECPublicKey(const EC_KEY *key, unsigned char **outp);
    340 
    341 
    342 #if defined(__cplusplus)
    343 }  // extern C
    344 
    345 extern "C++" {
    346 
    347 BSSL_NAMESPACE_BEGIN
    348 
    349 BORINGSSL_MAKE_DELETER(EC_KEY, EC_KEY_free)
    350 BORINGSSL_MAKE_UP_REF(EC_KEY, EC_KEY_up_ref)
    351 
    352 BSSL_NAMESPACE_END
    353 
    354 }  // extern C++
    355 
    356 #endif
    357 
    358 #endif  // OPENSSL_HEADER_EC_KEY_H