A local copy of OpenSSL from GitHub
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
 

527 lines
16 KiB

/*
* Copyright 2020 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the Apache License 2.0 (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
/*
* ECDSA low level APIs are deprecated for public use, but still ok for
* internal use.
*/
#include "internal/deprecated.h"
#include <string.h> /* memcpy */
#include <openssl/crypto.h>
#include <openssl/core_numbers.h>
#include <openssl/core_names.h>
#include <openssl/dsa.h>
#include <openssl/params.h>
#include <openssl/evp.h>
#include <openssl/err.h>
#include "internal/nelem.h"
#include "internal/sizes.h"
#include "internal/cryptlib.h"
#include "prov/providercommonerr.h"
#include "prov/implementations.h"
#include "prov/provider_ctx.h"
#include "crypto/ec.h"
#include "prov/der_ec.h"
static OSSL_OP_signature_newctx_fn ecdsa_newctx;
static OSSL_OP_signature_sign_init_fn ecdsa_signature_init;
static OSSL_OP_signature_verify_init_fn ecdsa_signature_init;
static OSSL_OP_signature_sign_fn ecdsa_sign;
static OSSL_OP_signature_verify_fn ecdsa_verify;
static OSSL_OP_signature_digest_sign_init_fn ecdsa_digest_signverify_init;
static OSSL_OP_signature_digest_sign_update_fn ecdsa_digest_signverify_update;
static OSSL_OP_signature_digest_sign_final_fn ecdsa_digest_sign_final;
static OSSL_OP_signature_digest_verify_init_fn ecdsa_digest_signverify_init;
static OSSL_OP_signature_digest_verify_update_fn ecdsa_digest_signverify_update;
static OSSL_OP_signature_digest_verify_final_fn ecdsa_digest_verify_final;
static OSSL_OP_signature_freectx_fn ecdsa_freectx;
static OSSL_OP_signature_dupctx_fn ecdsa_dupctx;
static OSSL_OP_signature_get_ctx_params_fn ecdsa_get_ctx_params;
static OSSL_OP_signature_gettable_ctx_params_fn ecdsa_gettable_ctx_params;
static OSSL_OP_signature_set_ctx_params_fn ecdsa_set_ctx_params;
static OSSL_OP_signature_settable_ctx_params_fn ecdsa_settable_ctx_params;
static OSSL_OP_signature_get_ctx_md_params_fn ecdsa_get_ctx_md_params;
static OSSL_OP_signature_gettable_ctx_md_params_fn ecdsa_gettable_ctx_md_params;
static OSSL_OP_signature_set_ctx_md_params_fn ecdsa_set_ctx_md_params;
static OSSL_OP_signature_settable_ctx_md_params_fn ecdsa_settable_ctx_md_params;
/*
* What's passed as an actual key is defined by the KEYMGMT interface.
* We happen to know that our KEYMGMT simply passes DSA structures, so
* we use that here too.
*/
typedef struct {
OPENSSL_CTX *libctx;
EC_KEY *ec;
char mdname[OSSL_MAX_NAME_SIZE];
/* The Algorithm Identifier of the combined signature algorithm */
unsigned char aid_buf[OSSL_MAX_ALGORITHM_ID_SIZE];
unsigned char *aid;
size_t aid_len;
size_t mdsize;
EVP_MD *md;
EVP_MD_CTX *mdctx;
/*
* This indicates that KAT (CAVS) test is running. Externally an app will
* override the random callback such that the generated private key and k
* are known.
* Normal operation will loop to choose a new k if the signature is not
* valid - but for this mode of operation it forces a failure instead.
*/
unsigned int kattest;
/*
* Internally used to cache the results of calling the EC group
* sign_setup() methods which are then passed to the sign operation.
* This is used by CAVS failure tests to terminate a loop if the signature
* is not valid.
* This could of also been done with a simple flag.
*/
BIGNUM *kinv;
BIGNUM *r;
} PROV_ECDSA_CTX;
static void *ecdsa_newctx(void *provctx)
{
PROV_ECDSA_CTX *ctx = OPENSSL_zalloc(sizeof(PROV_ECDSA_CTX));
if (ctx == NULL)
return NULL;
ctx->libctx = PROV_LIBRARY_CONTEXT_OF(provctx);
return ctx;
}
static int ecdsa_signature_init(void *vctx, void *ec)
{
PROV_ECDSA_CTX *ctx = (PROV_ECDSA_CTX *)vctx;
if (ctx == NULL || ec == NULL || !EC_KEY_up_ref(ec))
return 0;
EC_KEY_free(ctx->ec);
ctx->ec = ec;
return 1;
}
static int ecdsa_sign(void *vctx, unsigned char *sig, size_t *siglen,
size_t sigsize, const unsigned char *tbs, size_t tbslen)
{
PROV_ECDSA_CTX *ctx = (PROV_ECDSA_CTX *)vctx;
int ret;
unsigned int sltmp;
size_t ecsize = ECDSA_size(ctx->ec);
if (sig == NULL) {
*siglen = ecsize;
return 1;
}
if (ctx->kattest && !ECDSA_sign_setup(ctx->ec, NULL, &ctx->kinv, &ctx->r))
return 0;
if (sigsize < (size_t)ecsize)
return 0;
if (ctx->mdsize != 0 && tbslen != ctx->mdsize)
return 0;
ret = ECDSA_sign_ex(0, tbs, tbslen, sig, &sltmp, ctx->kinv, ctx->r, ctx->ec);
if (ret <= 0)
return 0;
*siglen = sltmp;
return 1;
}
static int ecdsa_verify(void *vctx, const unsigned char *sig, size_t siglen,
const unsigned char *tbs, size_t tbslen)
{
PROV_ECDSA_CTX *ctx = (PROV_ECDSA_CTX *)vctx;
if (ctx->mdsize != 0 && tbslen != ctx->mdsize)
return 0;
return ECDSA_verify(0, tbs, tbslen, sig, siglen, ctx->ec);
}
static int get_md_nid(const EVP_MD *md)
{
/*
* Because the ECDSA library deals with NIDs, we need to translate.
* We do so using EVP_MD_is_a(), and therefore need a name to NID
* map.
*/
static const OSSL_ITEM name_to_nid[] = {
{ NID_sha1, OSSL_DIGEST_NAME_SHA1 },
{ NID_sha224, OSSL_DIGEST_NAME_SHA2_224 },
{ NID_sha256, OSSL_DIGEST_NAME_SHA2_256 },
{ NID_sha384, OSSL_DIGEST_NAME_SHA2_384 },
{ NID_sha512, OSSL_DIGEST_NAME_SHA2_512 },
{ NID_sha3_224, OSSL_DIGEST_NAME_SHA3_224 },
{ NID_sha3_256, OSSL_DIGEST_NAME_SHA3_256 },
{ NID_sha3_384, OSSL_DIGEST_NAME_SHA3_384 },
{ NID_sha3_512, OSSL_DIGEST_NAME_SHA3_512 },
/* TODO - Add SHAKE OIDS when they are standardized */
};
size_t i;
int mdnid = NID_undef;
if (md == NULL)
goto end;
for (i = 0; i < OSSL_NELEM(name_to_nid); i++) {
if (EVP_MD_is_a(md, name_to_nid[i].ptr)) {
mdnid = (int)name_to_nid[i].id;
break;
}
}
if (mdnid == NID_undef)
ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_DIGEST);
end:
return mdnid;
}
static void free_md(PROV_ECDSA_CTX *ctx)
{
EVP_MD_CTX_free(ctx->mdctx);
EVP_MD_free(ctx->md);
ctx->mdctx = NULL;
ctx->md = NULL;
ctx->mdsize = 0;
}
static int ecdsa_digest_signverify_init(void *vctx, const char *mdname,
const char *props, void *ec)
{
PROV_ECDSA_CTX *ctx = (PROV_ECDSA_CTX *)vctx;
int md_nid = NID_undef;
WPACKET pkt;
free_md(ctx);
if (!ecdsa_signature_init(vctx, ec))
return 0;
ctx->md = EVP_MD_fetch(ctx->libctx, mdname, props);
if ((md_nid = get_md_nid(ctx->md)) == NID_undef)
goto error;
ctx->mdsize = EVP_MD_size(ctx->md);
ctx->mdctx = EVP_MD_CTX_new();
if (ctx->mdctx == NULL)
goto error;
/*
* TODO(3.0) Should we care about DER writing errors?
* All it really means is that for some reason, there's no
* AlgorithmIdentifier to be had, but the operation itself is
* still valid, just as long as it's not used to construct
* anything that needs an AlgorithmIdentifier.
*/
ctx->aid_len = 0;
if (WPACKET_init_der(&pkt, ctx->aid_buf, sizeof(ctx->aid_buf))
&& DER_w_algorithmIdentifier_ECDSA_with(&pkt, -1, ctx->ec, md_nid)
&& WPACKET_finish(&pkt)) {
WPACKET_get_total_written(&pkt, &ctx->aid_len);
ctx->aid = WPACKET_get_curr(&pkt);
}
WPACKET_cleanup(&pkt);
if (!EVP_DigestInit_ex(ctx->mdctx, ctx->md, NULL))
goto error;
return 1;
error:
free_md(ctx);
return 0;
}
int ecdsa_digest_signverify_update(void *vctx, const unsigned char *data,
size_t datalen)
{
PROV_ECDSA_CTX *ctx = (PROV_ECDSA_CTX *)vctx;
if (ctx == NULL || ctx->mdctx == NULL)
return 0;
return EVP_DigestUpdate(ctx->mdctx, data, datalen);
}
int ecdsa_digest_sign_final(void *vctx, unsigned char *sig, size_t *siglen,
size_t sigsize)
{
PROV_ECDSA_CTX *ctx = (PROV_ECDSA_CTX *)vctx;
unsigned char digest[EVP_MAX_MD_SIZE];
unsigned int dlen = 0;
if (ctx == NULL || ctx->mdctx == NULL)
return 0;
/*
* If sig is NULL then we're just finding out the sig size. Other fields
* are ignored. Defer to ecdsa_sign.
*/
if (sig != NULL) {
/*
* TODO(3.0): There is the possibility that some externally provided
* digests exceed EVP_MAX_MD_SIZE. We should probably handle that somehow -
* but that problem is much larger than just in DSA.
*/
if (!EVP_DigestFinal_ex(ctx->mdctx, digest, &dlen))
return 0;
}
return ecdsa_sign(vctx, sig, siglen, sigsize, digest, (size_t)dlen);
}
int ecdsa_digest_verify_final(void *vctx, const unsigned char *sig,
size_t siglen)
{
PROV_ECDSA_CTX *ctx = (PROV_ECDSA_CTX *)vctx;
unsigned char digest[EVP_MAX_MD_SIZE];
unsigned int dlen = 0;
if (ctx == NULL || ctx->mdctx == NULL)
return 0;
/*
* TODO(3.0): There is the possibility that some externally provided
* digests exceed EVP_MAX_MD_SIZE. We should probably handle that somehow -
* but that problem is much larger than just in DSA.
*/
if (!EVP_DigestFinal_ex(ctx->mdctx, digest, &dlen))
return 0;
return ecdsa_verify(ctx, sig, siglen, digest, (size_t)dlen);
}
static void ecdsa_freectx(void *vctx)
{
PROV_ECDSA_CTX *ctx = (PROV_ECDSA_CTX *)vctx;
free_md(ctx);
EC_KEY_free(ctx->ec);
BN_clear_free(ctx->kinv);
BN_clear_free(ctx->r);
OPENSSL_free(ctx);
}
static void *ecdsa_dupctx(void *vctx)
{
PROV_ECDSA_CTX *srcctx = (PROV_ECDSA_CTX *)vctx;
PROV_ECDSA_CTX *dstctx;
dstctx = OPENSSL_zalloc(sizeof(*srcctx));
if (dstctx == NULL)
return NULL;
*dstctx = *srcctx;
dstctx->ec = NULL;
dstctx->md = NULL;
dstctx->mdctx = NULL;
if (srcctx->ec != NULL && !EC_KEY_up_ref(srcctx->ec))
goto err;
/* Test KATS should not need to be supported */
if (srcctx->kinv != NULL || srcctx->r != NULL)
goto err;
dstctx->ec = srcctx->ec;
if (srcctx->md != NULL && !EVP_MD_up_ref(srcctx->md))
goto err;
dstctx->md = srcctx->md;
if (srcctx->mdctx != NULL) {
dstctx->mdctx = EVP_MD_CTX_new();
if (dstctx->mdctx == NULL
|| !EVP_MD_CTX_copy_ex(dstctx->mdctx, srcctx->mdctx))
goto err;
}
return dstctx;
err:
ecdsa_freectx(dstctx);
return NULL;
}
static int ecdsa_get_ctx_params(void *vctx, OSSL_PARAM *params)
{
PROV_ECDSA_CTX *ctx = (PROV_ECDSA_CTX *)vctx;
OSSL_PARAM *p;
if (ctx == NULL || params == NULL)
return 0;
p = OSSL_PARAM_locate(params, OSSL_SIGNATURE_PARAM_ALGORITHM_ID);
if (p != NULL && !OSSL_PARAM_set_octet_string(p, ctx->aid, ctx->aid_len))
return 0;
p = OSSL_PARAM_locate(params, OSSL_SIGNATURE_PARAM_DIGEST_SIZE);
if (p != NULL && !OSSL_PARAM_set_size_t(p, ctx->mdsize))
return 0;
p = OSSL_PARAM_locate(params, OSSL_SIGNATURE_PARAM_DIGEST);
if (p != NULL && !OSSL_PARAM_set_utf8_string(p, ctx->md == NULL
? ctx->mdname
: EVP_MD_name(ctx->md)))
return 0;
return 1;
}
static const OSSL_PARAM known_gettable_ctx_params[] = {
OSSL_PARAM_octet_string(OSSL_SIGNATURE_PARAM_ALGORITHM_ID, NULL, 0),
OSSL_PARAM_size_t(OSSL_SIGNATURE_PARAM_DIGEST_SIZE, NULL),
OSSL_PARAM_utf8_string(OSSL_SIGNATURE_PARAM_DIGEST, NULL, 0),
OSSL_PARAM_END
};
static const OSSL_PARAM *ecdsa_gettable_ctx_params(void)
{
return known_gettable_ctx_params;
}
static int ecdsa_set_ctx_params(void *vctx, const OSSL_PARAM params[])
{
PROV_ECDSA_CTX *ctx = (PROV_ECDSA_CTX *)vctx;
const OSSL_PARAM *p;
char *mdname;
if (ctx == NULL || params == NULL)
return 0;
if (ctx->md != NULL) {
/*
* You cannot set the digest name/size when doing a DigestSign or
* DigestVerify.
*/
return 1;
}
p = OSSL_PARAM_locate_const(params, OSSL_SIGNATURE_PARAM_KAT);
if (p != NULL && !OSSL_PARAM_get_uint(p, &ctx->kattest))
return 0;
p = OSSL_PARAM_locate_const(params, OSSL_SIGNATURE_PARAM_DIGEST_SIZE);
if (p != NULL && !OSSL_PARAM_get_size_t(p, &ctx->mdsize))
return 0;
/*
* We never actually use the mdname, but we do support getting it later.
* This can be useful for applications that want to know the MD that they
* previously set.
*/
p = OSSL_PARAM_locate_const(params, OSSL_SIGNATURE_PARAM_DIGEST);
mdname = ctx->mdname;
if (p != NULL
&& !OSSL_PARAM_get_utf8_string(p, &mdname, sizeof(ctx->mdname)))
return 0;
return 1;
}
static const OSSL_PARAM known_settable_ctx_params[] = {
OSSL_PARAM_size_t(OSSL_SIGNATURE_PARAM_DIGEST_SIZE, NULL),
OSSL_PARAM_utf8_string(OSSL_SIGNATURE_PARAM_DIGEST, NULL, 0),
OSSL_PARAM_uint(OSSL_SIGNATURE_PARAM_KAT, NULL),
OSSL_PARAM_END
};
static const OSSL_PARAM *ecdsa_settable_ctx_params(void)
{
/*
* TODO(3.0): Should this function return a different set of settable ctx
* params if the ctx is being used for a DigestSign/DigestVerify? In that
* case it is not allowed to set the digest size/digest name because the
* digest is explicitly set as part of the init.
*/
return known_settable_ctx_params;
}
static int ecdsa_get_ctx_md_params(void *vctx, OSSL_PARAM *params)
{
PROV_ECDSA_CTX *ctx = (PROV_ECDSA_CTX *)vctx;
if (ctx->mdctx == NULL)
return 0;
return EVP_MD_CTX_get_params(ctx->mdctx, params);
}
static const OSSL_PARAM *ecdsa_gettable_ctx_md_params(void *vctx)
{
PROV_ECDSA_CTX *ctx = (PROV_ECDSA_CTX *)vctx;
if (ctx->md == NULL)
return 0;
return EVP_MD_gettable_ctx_params(ctx->md);
}
static int ecdsa_set_ctx_md_params(void *vctx, const OSSL_PARAM params[])
{
PROV_ECDSA_CTX *ctx = (PROV_ECDSA_CTX *)vctx;
if (ctx->mdctx == NULL)
return 0;
return EVP_MD_CTX_set_params(ctx->mdctx, params);
}
static const OSSL_PARAM *ecdsa_settable_ctx_md_params(void *vctx)
{
PROV_ECDSA_CTX *ctx = (PROV_ECDSA_CTX *)vctx;
if (ctx->md == NULL)
return 0;
return EVP_MD_settable_ctx_params(ctx->md);
}
const OSSL_DISPATCH ecdsa_signature_functions[] = {
{ OSSL_FUNC_SIGNATURE_NEWCTX, (void (*)(void))ecdsa_newctx },
{ OSSL_FUNC_SIGNATURE_SIGN_INIT, (void (*)(void))ecdsa_signature_init },
{ OSSL_FUNC_SIGNATURE_SIGN, (void (*)(void))ecdsa_sign },
{ OSSL_FUNC_SIGNATURE_VERIFY_INIT, (void (*)(void))ecdsa_signature_init },
{ OSSL_FUNC_SIGNATURE_VERIFY, (void (*)(void))ecdsa_verify },
{ OSSL_FUNC_SIGNATURE_DIGEST_SIGN_INIT,
(void (*)(void))ecdsa_digest_signverify_init },
{ OSSL_FUNC_SIGNATURE_DIGEST_SIGN_UPDATE,
(void (*)(void))ecdsa_digest_signverify_update },
{ OSSL_FUNC_SIGNATURE_DIGEST_SIGN_FINAL,
(void (*)(void))ecdsa_digest_sign_final },
{ OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_INIT,
(void (*)(void))ecdsa_digest_signverify_init },
{ OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_UPDATE,
(void (*)(void))ecdsa_digest_signverify_update },
{ OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_FINAL,
(void (*)(void))ecdsa_digest_verify_final },
{ OSSL_FUNC_SIGNATURE_FREECTX, (void (*)(void))ecdsa_freectx },
{ OSSL_FUNC_SIGNATURE_DUPCTX, (void (*)(void))ecdsa_dupctx },
{ OSSL_FUNC_SIGNATURE_GET_CTX_PARAMS, (void (*)(void))ecdsa_get_ctx_params },
{ OSSL_FUNC_SIGNATURE_GETTABLE_CTX_PARAMS,
(void (*)(void))ecdsa_gettable_ctx_params },
{ OSSL_FUNC_SIGNATURE_SET_CTX_PARAMS, (void (*)(void))ecdsa_set_ctx_params },
{ OSSL_FUNC_SIGNATURE_SETTABLE_CTX_PARAMS,
(void (*)(void))ecdsa_settable_ctx_params },
{ OSSL_FUNC_SIGNATURE_GET_CTX_MD_PARAMS,
(void (*)(void))ecdsa_get_ctx_md_params },
{ OSSL_FUNC_SIGNATURE_GETTABLE_CTX_MD_PARAMS,
(void (*)(void))ecdsa_gettable_ctx_md_params },
{ OSSL_FUNC_SIGNATURE_SET_CTX_MD_PARAMS,
(void (*)(void))ecdsa_set_ctx_md_params },
{ OSSL_FUNC_SIGNATURE_SETTABLE_CTX_MD_PARAMS,
(void (*)(void))ecdsa_settable_ctx_md_params },
{ 0, NULL }
};