2 * Copyright 2006-2016 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the OpenSSL license (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
11 #include "internal/cryptlib.h"
12 #include <openssl/asn1t.h>
13 #include <openssl/x509.h>
14 #include <openssl/ec.h>
16 #include <openssl/evp.h>
17 #include "internal/evp_int.h"
19 /* EC pkey context structure */
22 /* Key and paramgen group */
26 /* Duplicate key if custom cofactor needed */
29 signed char cofactor_mode
;
30 /* KDF (if any) to use for ECDH */
32 /* Message digest to use for key derivation */
34 /* User key material */
35 unsigned char *kdf_ukm
;
37 /* KDF output length */
41 static int pkey_ec_init(EVP_PKEY_CTX
*ctx
)
45 dctx
= OPENSSL_zalloc(sizeof(*dctx
));
49 dctx
->cofactor_mode
= -1;
50 dctx
->kdf_type
= EVP_PKEY_ECDH_KDF_NONE
;
55 static int pkey_ec_copy(EVP_PKEY_CTX
*dst
, EVP_PKEY_CTX
*src
)
57 EC_PKEY_CTX
*dctx
, *sctx
;
58 if (!pkey_ec_init(dst
))
62 if (sctx
->gen_group
) {
63 dctx
->gen_group
= EC_GROUP_dup(sctx
->gen_group
);
70 dctx
->co_key
= EC_KEY_dup(sctx
->co_key
);
74 dctx
->kdf_type
= sctx
->kdf_type
;
75 dctx
->kdf_md
= sctx
->kdf_md
;
76 dctx
->kdf_outlen
= sctx
->kdf_outlen
;
78 dctx
->kdf_ukm
= OPENSSL_memdup(sctx
->kdf_ukm
, sctx
->kdf_ukmlen
);
83 dctx
->kdf_ukmlen
= sctx
->kdf_ukmlen
;
87 static void pkey_ec_cleanup(EVP_PKEY_CTX
*ctx
)
89 EC_PKEY_CTX
*dctx
= ctx
->data
;
91 EC_GROUP_free(dctx
->gen_group
);
92 EC_KEY_free(dctx
->co_key
);
93 OPENSSL_free(dctx
->kdf_ukm
);
98 static int pkey_ec_sign(EVP_PKEY_CTX
*ctx
, unsigned char *sig
, size_t *siglen
,
99 const unsigned char *tbs
, size_t tbslen
)
103 EC_PKEY_CTX
*dctx
= ctx
->data
;
104 EC_KEY
*ec
= ctx
->pkey
->pkey
.ec
;
107 *siglen
= ECDSA_size(ec
);
109 } else if (*siglen
< (size_t)ECDSA_size(ec
)) {
110 ECerr(EC_F_PKEY_EC_SIGN
, EC_R_BUFFER_TOO_SMALL
);
115 type
= EVP_MD_type(dctx
->md
);
119 ret
= ECDSA_sign(type
, tbs
, tbslen
, sig
, &sltmp
, ec
);
123 *siglen
= (size_t)sltmp
;
127 static int pkey_ec_verify(EVP_PKEY_CTX
*ctx
,
128 const unsigned char *sig
, size_t siglen
,
129 const unsigned char *tbs
, size_t tbslen
)
132 EC_PKEY_CTX
*dctx
= ctx
->data
;
133 EC_KEY
*ec
= ctx
->pkey
->pkey
.ec
;
136 type
= EVP_MD_type(dctx
->md
);
140 ret
= ECDSA_verify(type
, tbs
, tbslen
, sig
, siglen
, ec
);
145 #ifndef OPENSSL_NO_EC
146 static int pkey_ec_derive(EVP_PKEY_CTX
*ctx
, unsigned char *key
,
151 const EC_POINT
*pubkey
= NULL
;
153 EC_PKEY_CTX
*dctx
= ctx
->data
;
154 if (!ctx
->pkey
|| !ctx
->peerkey
) {
155 ECerr(EC_F_PKEY_EC_DERIVE
, EC_R_KEYS_NOT_SET
);
159 eckey
= dctx
->co_key
? dctx
->co_key
: ctx
->pkey
->pkey
.ec
;
162 const EC_GROUP
*group
;
163 group
= EC_KEY_get0_group(eckey
);
164 *keylen
= (EC_GROUP_get_degree(group
) + 7) / 8;
167 pubkey
= EC_KEY_get0_public_key(ctx
->peerkey
->pkey
.ec
);
170 * NB: unlike PKCS#3 DH, if *outlen is less than maximum size this is not
171 * an error, the result is truncated.
176 ret
= ECDH_compute_key(key
, outlen
, pubkey
, eckey
, 0);
183 static int pkey_ec_kdf_derive(EVP_PKEY_CTX
*ctx
,
184 unsigned char *key
, size_t *keylen
)
186 EC_PKEY_CTX
*dctx
= ctx
->data
;
187 unsigned char *ktmp
= NULL
;
190 if (dctx
->kdf_type
== EVP_PKEY_ECDH_KDF_NONE
)
191 return pkey_ec_derive(ctx
, key
, keylen
);
193 *keylen
= dctx
->kdf_outlen
;
196 if (*keylen
!= dctx
->kdf_outlen
)
198 if (!pkey_ec_derive(ctx
, NULL
, &ktmplen
))
200 ktmp
= OPENSSL_malloc(ktmplen
);
203 if (!pkey_ec_derive(ctx
, ktmp
, &ktmplen
))
206 if (!ECDH_KDF_X9_62(key
, *keylen
, ktmp
, ktmplen
,
207 dctx
->kdf_ukm
, dctx
->kdf_ukmlen
, dctx
->kdf_md
))
212 OPENSSL_clear_free(ktmp
, ktmplen
);
217 static int pkey_ec_ctrl(EVP_PKEY_CTX
*ctx
, int type
, int p1
, void *p2
)
219 EC_PKEY_CTX
*dctx
= ctx
->data
;
222 case EVP_PKEY_CTRL_EC_PARAMGEN_CURVE_NID
:
223 group
= EC_GROUP_new_by_curve_name(p1
);
225 ECerr(EC_F_PKEY_EC_CTRL
, EC_R_INVALID_CURVE
);
228 EC_GROUP_free(dctx
->gen_group
);
229 dctx
->gen_group
= group
;
232 case EVP_PKEY_CTRL_EC_PARAM_ENC
:
233 if (!dctx
->gen_group
) {
234 ECerr(EC_F_PKEY_EC_CTRL
, EC_R_NO_PARAMETERS_SET
);
237 EC_GROUP_set_asn1_flag(dctx
->gen_group
, p1
);
240 #ifndef OPENSSL_NO_EC
241 case EVP_PKEY_CTRL_EC_ECDH_COFACTOR
:
243 if (dctx
->cofactor_mode
!= -1)
244 return dctx
->cofactor_mode
;
246 EC_KEY
*ec_key
= ctx
->pkey
->pkey
.ec
;
247 return EC_KEY_get_flags(ec_key
) & EC_FLAG_COFACTOR_ECDH
? 1 :
250 } else if (p1
< -1 || p1
> 1)
252 dctx
->cofactor_mode
= p1
;
254 EC_KEY
*ec_key
= ctx
->pkey
->pkey
.ec
;
257 /* If cofactor is 1 cofactor mode does nothing */
258 if (BN_is_one(ec_key
->group
->cofactor
))
261 dctx
->co_key
= EC_KEY_dup(ec_key
);
266 EC_KEY_set_flags(dctx
->co_key
, EC_FLAG_COFACTOR_ECDH
);
268 EC_KEY_clear_flags(dctx
->co_key
, EC_FLAG_COFACTOR_ECDH
);
270 EC_KEY_free(dctx
->co_key
);
276 case EVP_PKEY_CTRL_EC_KDF_TYPE
:
278 return dctx
->kdf_type
;
279 if (p1
!= EVP_PKEY_ECDH_KDF_NONE
&& p1
!= EVP_PKEY_ECDH_KDF_X9_62
)
284 case EVP_PKEY_CTRL_EC_KDF_MD
:
288 case EVP_PKEY_CTRL_GET_EC_KDF_MD
:
289 *(const EVP_MD
**)p2
= dctx
->kdf_md
;
292 case EVP_PKEY_CTRL_EC_KDF_OUTLEN
:
295 dctx
->kdf_outlen
= (size_t)p1
;
298 case EVP_PKEY_CTRL_GET_EC_KDF_OUTLEN
:
299 *(int *)p2
= dctx
->kdf_outlen
;
302 case EVP_PKEY_CTRL_EC_KDF_UKM
:
303 OPENSSL_free(dctx
->kdf_ukm
);
306 dctx
->kdf_ukmlen
= p1
;
308 dctx
->kdf_ukmlen
= 0;
311 case EVP_PKEY_CTRL_GET_EC_KDF_UKM
:
312 *(unsigned char **)p2
= dctx
->kdf_ukm
;
313 return dctx
->kdf_ukmlen
;
315 case EVP_PKEY_CTRL_MD
:
316 if (EVP_MD_type((const EVP_MD
*)p2
) != NID_sha1
&&
317 EVP_MD_type((const EVP_MD
*)p2
) != NID_ecdsa_with_SHA1
&&
318 EVP_MD_type((const EVP_MD
*)p2
) != NID_sha224
&&
319 EVP_MD_type((const EVP_MD
*)p2
) != NID_sha256
&&
320 EVP_MD_type((const EVP_MD
*)p2
) != NID_sha384
&&
321 EVP_MD_type((const EVP_MD
*)p2
) != NID_sha512
) {
322 ECerr(EC_F_PKEY_EC_CTRL
, EC_R_INVALID_DIGEST_TYPE
);
328 case EVP_PKEY_CTRL_GET_MD
:
329 *(const EVP_MD
**)p2
= dctx
->md
;
332 case EVP_PKEY_CTRL_PEER_KEY
:
333 /* Default behaviour is OK */
334 case EVP_PKEY_CTRL_DIGESTINIT
:
335 case EVP_PKEY_CTRL_PKCS7_SIGN
:
336 case EVP_PKEY_CTRL_CMS_SIGN
:
345 static int pkey_ec_ctrl_str(EVP_PKEY_CTX
*ctx
,
346 const char *type
, const char *value
)
348 if (strcmp(type
, "ec_paramgen_curve") == 0) {
350 nid
= EC_curve_nist2nid(value
);
351 if (nid
== NID_undef
)
352 nid
= OBJ_sn2nid(value
);
353 if (nid
== NID_undef
)
354 nid
= OBJ_ln2nid(value
);
355 if (nid
== NID_undef
) {
356 ECerr(EC_F_PKEY_EC_CTRL_STR
, EC_R_INVALID_CURVE
);
359 return EVP_PKEY_CTX_set_ec_paramgen_curve_nid(ctx
, nid
);
360 } else if (strcmp(type
, "ec_param_enc") == 0) {
362 if (strcmp(value
, "explicit") == 0)
364 else if (strcmp(value
, "named_curve") == 0)
365 param_enc
= OPENSSL_EC_NAMED_CURVE
;
368 return EVP_PKEY_CTX_set_ec_param_enc(ctx
, param_enc
);
369 } else if (strcmp(type
, "ecdh_kdf_md") == 0) {
371 if ((md
= EVP_get_digestbyname(value
)) == NULL
) {
372 ECerr(EC_F_PKEY_EC_CTRL_STR
, EC_R_INVALID_DIGEST
);
375 return EVP_PKEY_CTX_set_ecdh_kdf_md(ctx
, md
);
376 } else if (strcmp(type
, "ecdh_cofactor_mode") == 0) {
378 co_mode
= atoi(value
);
379 return EVP_PKEY_CTX_set_ecdh_cofactor_mode(ctx
, co_mode
);
385 static int pkey_ec_paramgen(EVP_PKEY_CTX
*ctx
, EVP_PKEY
*pkey
)
388 EC_PKEY_CTX
*dctx
= ctx
->data
;
390 if (dctx
->gen_group
== NULL
) {
391 ECerr(EC_F_PKEY_EC_PARAMGEN
, EC_R_NO_PARAMETERS_SET
);
397 ret
= EC_KEY_set_group(ec
, dctx
->gen_group
);
399 EVP_PKEY_assign_EC_KEY(pkey
, ec
);
405 static int pkey_ec_keygen(EVP_PKEY_CTX
*ctx
, EVP_PKEY
*pkey
)
408 EC_PKEY_CTX
*dctx
= ctx
->data
;
409 if (ctx
->pkey
== NULL
&& dctx
->gen_group
== NULL
) {
410 ECerr(EC_F_PKEY_EC_KEYGEN
, EC_R_NO_PARAMETERS_SET
);
416 EVP_PKEY_assign_EC_KEY(pkey
, ec
);
418 /* Note: if error return, pkey is freed by parent routine */
419 if (!EVP_PKEY_copy_parameters(pkey
, ctx
->pkey
))
422 if (!EC_KEY_set_group(ec
, dctx
->gen_group
))
425 return EC_KEY_generate_key(pkey
->pkey
.ec
);
428 const EVP_PKEY_METHOD ec_pkey_meth
= {
456 #ifndef OPENSSL_NO_EC