crypto/ec/ec_kmeth.c

   1 /*
   2  * Copyright 2015-2023 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the Apache License 2.0 (the "License").  You may not use
   5  * this file except in compliance with the License.  You can obtain a copy
   6  * in the file LICENSE in the source distribution or at
   7  * https://www.openssl.org/source/license.html
   8  */
   9
  10 /*
  11  * ECDH and ECDSA low level APIs are deprecated for public use, but still ok
  12  * for internal use.
  13  */
  14 #include "internal/deprecated.h"
  15
  16 #include <string.h>
  17 #include <openssl/ec.h>
  18 #ifndef FIPS_MODULE
  19 # include <openssl/engine.h>
  20 #endif
  21 #include <openssl/err.h>
  22 #include "ec_local.h"
  23
  24
  25 static const EC_KEY_METHOD openssl_ec_key_method = {
  26     "OpenSSL EC_KEY method",
  27     0,
  28     0,0,0,0,0,0,
  29     ossl_ec_key_gen,
  30     ossl_ecdh_compute_key,
  31     ossl_ecdsa_sign,
  32     ossl_ecdsa_sign_setup,
  33     ossl_ecdsa_sign_sig,
  34     ossl_ecdsa_verify,
  35     ossl_ecdsa_verify_sig
  36 };
  37
  38 static const EC_KEY_METHOD *default_ec_key_meth = &openssl_ec_key_method;
  39
  40 const EC_KEY_METHOD *EC_KEY_OpenSSL(void)
  41 {
  42     return &openssl_ec_key_method;
  43 }
  44
  45 const EC_KEY_METHOD *EC_KEY_get_default_method(void)
  46 {
  47     return default_ec_key_meth;
  48 }
  49
  50 void EC_KEY_set_default_method(const EC_KEY_METHOD *meth)
  51 {
  52     if (meth == NULL)
  53         default_ec_key_meth = &openssl_ec_key_method;
  54     else
  55         default_ec_key_meth = meth;
  56 }
  57
  58 const EC_KEY_METHOD *EC_KEY_get_method(const EC_KEY *key)
  59 {
  60     return key->meth;
  61 }
  62
  63 int EC_KEY_set_method(EC_KEY *key, const EC_KEY_METHOD *meth)
  64 {
  65     void (*finish)(EC_KEY *key) = key->meth->finish;
  66
  67     if (finish != NULL)
  68         finish(key);
  69
  70 #if !defined(OPENSSL_NO_ENGINE) && !defined(FIPS_MODULE)
  71     ENGINE_finish(key->engine);
  72     key->engine = NULL;
  73 #endif
  74
  75     key->meth = meth;
  76     if (meth->init != NULL)
  77         return meth->init(key);
  78     return 1;
  79 }
  80
  81 EC_KEY *ossl_ec_key_new_method_int(OSSL_LIB_CTX *libctx, const char *propq,
  82                                    ENGINE *engine)
  83 {
  84     EC_KEY *ret = OPENSSL_zalloc(sizeof(*ret));
  85
  86     if (ret == NULL)
  87         return NULL;
  88
  89     if (!CRYPTO_NEW_REF(&ret->references, 1)) {
  90         OPENSSL_free(ret);
  91         return NULL;
  92     }
  93
  94     ret->libctx = libctx;
  95     if (propq != NULL) {
  96         ret->propq = OPENSSL_strdup(propq);
  97         if (ret->propq == NULL)
  98             goto err;
  99     }
 100
 101     ret->meth = EC_KEY_get_default_method();
 102 #if !defined(OPENSSL_NO_ENGINE) && !defined(FIPS_MODULE)
 103     if (engine != NULL) {
 104         if (!ENGINE_init(engine)) {
 105             ERR_raise(ERR_LIB_EC, ERR_R_ENGINE_LIB);
 106             goto err;
 107         }
 108         ret->engine = engine;
 109     } else
 110         ret->engine = ENGINE_get_default_EC();
 111     if (ret->engine != NULL) {
 112         ret->meth = ENGINE_get_EC(ret->engine);
 113         if (ret->meth == NULL) {
 114             ERR_raise(ERR_LIB_EC, ERR_R_ENGINE_LIB);
 115             goto err;
 116         }
 117     }
 118 #endif
 119
 120     ret->version = 1;
 121     ret->conv_form = POINT_CONVERSION_UNCOMPRESSED;
 122
 123 /* No ex_data inside the FIPS provider */
 124 #ifndef FIPS_MODULE
 125     if (!CRYPTO_new_ex_data(CRYPTO_EX_INDEX_EC_KEY, ret, &ret->ex_data)) {
 126         ERR_raise(ERR_LIB_EC, ERR_R_CRYPTO_LIB);
 127         goto err;
 128     }
 129 #endif
 130
 131     if (ret->meth->init != NULL && ret->meth->init(ret) == 0) {
 132         ERR_raise(ERR_LIB_EC, ERR_R_INIT_FAIL);
 133         goto err;
 134     }
 135     return ret;
 136
 137  err:
 138     EC_KEY_free(ret);
 139     return NULL;
 140 }
 141
 142 #ifndef FIPS_MODULE
 143 EC_KEY *EC_KEY_new_method(ENGINE *engine)
 144 {
 145     return ossl_ec_key_new_method_int(NULL, NULL, engine);
 146 }
 147 #endif
 148
 149 int ECDH_compute_key(void *out, size_t outlen, const EC_POINT *pub_key,
 150                      const EC_KEY *eckey,
 151                      void *(*KDF) (const void *in, size_t inlen, void *out,
 152                                    size_t *outlen))
 153 {
 154     unsigned char *sec = NULL;
 155     size_t seclen;
 156     if (eckey->meth->compute_key == NULL) {
 157         ERR_raise(ERR_LIB_EC, EC_R_OPERATION_NOT_SUPPORTED);
 158         return 0;
 159     }
 160     if (outlen > INT_MAX) {
 161         ERR_raise(ERR_LIB_EC, EC_R_INVALID_OUTPUT_LENGTH);
 162         return 0;
 163     }
 164     if (!eckey->meth->compute_key(&sec, &seclen, pub_key, eckey))
 165         return 0;
 166     if (KDF != NULL) {
 167         KDF(sec, seclen, out, &outlen);
 168     } else {
 169         if (outlen > seclen)
 170             outlen = seclen;
 171         memcpy(out, sec, outlen);
 172     }
 173     OPENSSL_clear_free(sec, seclen);
 174     return outlen;
 175 }
 176
 177 EC_KEY_METHOD *EC_KEY_METHOD_new(const EC_KEY_METHOD *meth)
 178 {
 179     EC_KEY_METHOD *ret = OPENSSL_zalloc(sizeof(*meth));
 180
 181     if (ret == NULL)
 182         return NULL;
 183     if (meth != NULL)
 184         *ret = *meth;
 185     ret->flags |= EC_KEY_METHOD_DYNAMIC;
 186     return ret;
 187 }
 188
 189 void EC_KEY_METHOD_free(EC_KEY_METHOD *meth)
 190 {
 191     if (meth->flags & EC_KEY_METHOD_DYNAMIC)
 192         OPENSSL_free(meth);
 193 }
 194
 195 void EC_KEY_METHOD_set_init(EC_KEY_METHOD *meth,
 196                             int (*init)(EC_KEY *key),
 197                             void (*finish)(EC_KEY *key),
 198                             int (*copy)(EC_KEY *dest, const EC_KEY *src),
 199                             int (*set_group)(EC_KEY *key, const EC_GROUP *grp),
 200                             int (*set_private)(EC_KEY *key,
 201                                                const BIGNUM *priv_key),
 202                             int (*set_public)(EC_KEY *key,
 203                                               const EC_POINT *pub_key))
 204 {
 205     meth->init = init;
 206     meth->finish = finish;
 207     meth->copy = copy;
 208     meth->set_group = set_group;
 209     meth->set_private = set_private;
 210     meth->set_public = set_public;
 211 }
 212
 213 void EC_KEY_METHOD_set_keygen(EC_KEY_METHOD *meth,
 214                               int (*keygen)(EC_KEY *key))
 215 {
 216     meth->keygen = keygen;
 217 }
 218
 219 void EC_KEY_METHOD_set_compute_key(EC_KEY_METHOD *meth,
 220                                    int (*ckey)(unsigned char **psec,
 221                                                size_t *pseclen,
 222                                                const EC_POINT *pub_key,
 223                                                const EC_KEY *ecdh))
 224 {
 225     meth->compute_key = ckey;
 226 }
 227
 228 void EC_KEY_METHOD_set_sign(EC_KEY_METHOD *meth,
 229                             int (*sign)(int type, const unsigned char *dgst,
 230                                         int dlen, unsigned char *sig,
 231                                         unsigned int *siglen,
 232                                         const BIGNUM *kinv, const BIGNUM *r,
 233                                         EC_KEY *eckey),
 234                             int (*sign_setup)(EC_KEY *eckey, BN_CTX *ctx_in,
 235                                               BIGNUM **kinvp, BIGNUM **rp),
 236                             ECDSA_SIG *(*sign_sig)(const unsigned char *dgst,
 237                                                    int dgst_len,
 238                                                    const BIGNUM *in_kinv,
 239                                                    const BIGNUM *in_r,
 240                                                    EC_KEY *eckey))
 241 {
 242     meth->sign = sign;
 243     meth->sign_setup = sign_setup;
 244     meth->sign_sig = sign_sig;
 245 }
 246
 247 void EC_KEY_METHOD_set_verify(EC_KEY_METHOD *meth,
 248                               int (*verify)(int type, const unsigned
 249                                             char *dgst, int dgst_len,
 250                                             const unsigned char *sigbuf,
 251                                             int sig_len, EC_KEY *eckey),
 252                               int (*verify_sig)(const unsigned char *dgst,
 253                                                 int dgst_len,
 254                                                 const ECDSA_SIG *sig,
 255                                                 EC_KEY *eckey))
 256 {
 257     meth->verify = verify;
 258     meth->verify_sig = verify_sig;
 259 }
 260
 261 void EC_KEY_METHOD_get_init(const EC_KEY_METHOD *meth,
 262                             int (**pinit)(EC_KEY *key),
 263                             void (**pfinish)(EC_KEY *key),
 264                             int (**pcopy)(EC_KEY *dest, const EC_KEY *src),
 265                             int (**pset_group)(EC_KEY *key,
 266                                                const EC_GROUP *grp),
 267                             int (**pset_private)(EC_KEY *key,
 268                                                  const BIGNUM *priv_key),
 269                             int (**pset_public)(EC_KEY *key,
 270                                                 const EC_POINT *pub_key))
 271 {
 272     if (pinit != NULL)
 273         *pinit = meth->init;
 274     if (pfinish != NULL)
 275         *pfinish = meth->finish;
 276     if (pcopy != NULL)
 277         *pcopy = meth->copy;
 278     if (pset_group != NULL)
 279         *pset_group = meth->set_group;
 280     if (pset_private != NULL)
 281         *pset_private = meth->set_private;
 282     if (pset_public != NULL)
 283         *pset_public = meth->set_public;
 284 }
 285
 286 void EC_KEY_METHOD_get_keygen(const EC_KEY_METHOD *meth,
 287                               int (**pkeygen)(EC_KEY *key))
 288 {
 289     if (pkeygen != NULL)
 290         *pkeygen = meth->keygen;
 291 }
 292
 293 void EC_KEY_METHOD_get_compute_key(const EC_KEY_METHOD *meth,
 294                                    int (**pck)(unsigned char **pout,
 295                                                size_t *poutlen,
 296                                                const EC_POINT *pub_key,
 297                                                const EC_KEY *ecdh))
 298 {
 299     if (pck != NULL)
 300         *pck = meth->compute_key;
 301 }
 302
 303 void EC_KEY_METHOD_get_sign(const EC_KEY_METHOD *meth,
 304                             int (**psign)(int type, const unsigned char *dgst,
 305                                           int dlen, unsigned char *sig,
 306                                           unsigned int *siglen,
 307                                           const BIGNUM *kinv, const BIGNUM *r,
 308                                           EC_KEY *eckey),
 309                             int (**psign_setup)(EC_KEY *eckey, BN_CTX *ctx_in,
 310                                                 BIGNUM **kinvp, BIGNUM **rp),
 311                             ECDSA_SIG *(**psign_sig)(const unsigned char *dgst,
 312                                                      int dgst_len,
 313                                                      const BIGNUM *in_kinv,
 314                                                      const BIGNUM *in_r,
 315                                                      EC_KEY *eckey))
 316 {
 317     if (psign != NULL)
 318         *psign = meth->sign;
 319     if (psign_setup != NULL)
 320         *psign_setup = meth->sign_setup;
 321     if (psign_sig != NULL)
 322         *psign_sig = meth->sign_sig;
 323 }
 324
 325 void EC_KEY_METHOD_get_verify(const EC_KEY_METHOD *meth,
 326                               int (**pverify)(int type, const unsigned
 327                                               char *dgst, int dgst_len,
 328                                               const unsigned char *sigbuf,
 329                                               int sig_len, EC_KEY *eckey),
 330                               int (**pverify_sig)(const unsigned char *dgst,
 331                                                   int dgst_len,
 332                                                   const ECDSA_SIG *sig,
 333                                                   EC_KEY *eckey))
 334 {
 335     if (pverify != NULL)
 336         *pverify = meth->verify;
 337     if (pverify_sig != NULL)
 338         *pverify_sig = meth->verify_sig;
 339 }