/*
- * Copyright 1995-2019 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 1995-2020 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
* https://www.openssl.org/source/license.html
*/
+/*
+ * DH low level APIs are deprecated for public use, but still ok for
+ * internal use.
+ */
+#include "internal/deprecated.h"
+
#include <stdio.h>
#include "internal/cryptlib.h"
#include "dh_local.h"
#include "crypto/bn.h"
#include "crypto/dh.h"
-#ifndef FIPS_MODE
static int generate_key(DH *dh);
-#endif /* FIPS_MODE */
-
static int dh_bn_mod_exp(const DH *dh, BIGNUM *r,
const BIGNUM *a, const BIGNUM *p,
const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *m_ctx);
static int dh_init(DH *dh);
static int dh_finish(DH *dh);
-int dh_compute_key(OPENSSL_CTX *libctx, unsigned char *key,
- const BIGNUM *pub_key, DH *dh)
+static int compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh)
{
BN_CTX *ctx = NULL;
BN_MONT_CTX *mont = NULL;
int check_result;
#endif
- if (BN_num_bits(dh->p) > OPENSSL_DH_MAX_MODULUS_BITS) {
+ if (BN_num_bits(dh->params.p) > OPENSSL_DH_MAX_MODULUS_BITS) {
DHerr(0, DH_R_MODULUS_TOO_LARGE);
goto err;
}
- if (BN_num_bits(dh->p) < DH_MIN_MODULUS_BITS) {
+ if (BN_num_bits(dh->params.p) < DH_MIN_MODULUS_BITS) {
DHerr(0, DH_R_MODULUS_TOO_SMALL);
return 0;
}
- ctx = BN_CTX_new_ex(libctx);
+ ctx = BN_CTX_new_ex(dh->libctx);
if (ctx == NULL)
goto err;
BN_CTX_start(ctx);
if (dh->flags & DH_FLAG_CACHE_MONT_P) {
mont = BN_MONT_CTX_set_locked(&dh->method_mont_p,
- dh->lock, dh->p, ctx);
+ dh->lock, dh->params.p, ctx);
BN_set_flags(dh->priv_key, BN_FLG_CONSTTIME);
if (!mont)
goto err;
goto err;
}
#endif
- if (!dh->meth->bn_mod_exp(dh, tmp, pub_key, dh->priv_key, dh->p, ctx,
+ if (!dh->meth->bn_mod_exp(dh, tmp, pub_key, dh->priv_key, dh->params.p, ctx,
mont)) {
DHerr(0, ERR_R_BN_LIB);
goto err;
return ret;
}
-static int compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh)
+int DH_compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh)
{
- return dh_compute_key(NULL, key, pub_key, dh);
+#ifdef FIPS_MODE
+ return compute_key(key, pub_key, dh);
+#else
+ return dh->meth->compute_key(key, pub_key, dh);
+#endif
}
-int dh_compute_key_padded(OPENSSL_CTX *libctx, unsigned char *key,
- const BIGNUM *pub_key, DH *dh)
+int DH_compute_key_padded(unsigned char *key, const BIGNUM *pub_key, DH *dh)
{
int rv, pad;
#ifdef FIPS_MODE
- rv = dh_compute_key(libctx, key, pub_key, dh);
+ rv = compute_key(key, pub_key, dh);
#else
rv = dh->meth->compute_key(key, pub_key, dh);
#endif
if (rv <= 0)
return rv;
- pad = BN_num_bytes(dh->p) - rv;
+ pad = BN_num_bytes(dh->params.p) - rv;
if (pad > 0) {
memmove(key + pad, key, rv);
memset(key, 0, pad);
return rv + pad;
}
-#ifndef FIPS_MODE
-int DH_compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh)
-{
- return dh->meth->compute_key(key, pub_key, dh);
-}
-
-int DH_compute_key_padded(unsigned char *key, const BIGNUM *pub_key, DH *dh)
-{
- return dh_compute_key_padded(NULL, key, pub_key, dh);
-}
-#endif
-
static DH_METHOD dh_ossl = {
"OpenSSL DH Method",
-#ifndef FIPS_MODE
generate_key,
-#else
- NULL, /* TODO(3.0) : solve this in a keygen related PR */
-#endif
compute_key,
dh_bn_mod_exp,
dh_init,
static int dh_init(DH *dh)
{
dh->flags |= DH_FLAG_CACHE_MONT_P;
+ ffc_params_init(&dh->params);
+ dh->dirty_cnt++;
return 1;
}
}
#ifndef FIPS_MODE
-
void DH_set_default_method(const DH_METHOD *meth)
{
default_DH_method = meth;
}
+#endif /* FIPS_MODE */
int DH_generate_key(DH *dh)
{
+#ifdef FIPS_MODE
+ return generate_key(dh);
+#else
return dh->meth->generate_key(dh);
+#endif
+}
+
+int dh_generate_public_key(BN_CTX *ctx, DH *dh, const BIGNUM *priv_key,
+ BIGNUM *pub_key)
+{
+ int ret = 0;
+ BIGNUM *prk = BN_new();
+ BN_MONT_CTX *mont = NULL;
+
+ if (prk == NULL)
+ return 0;
+
+ if (dh->flags & DH_FLAG_CACHE_MONT_P) {
+ mont = BN_MONT_CTX_set_locked(&dh->method_mont_p,
+ dh->lock, dh->params.p, ctx);
+ if (mont == NULL)
+ goto err;
+ }
+ BN_with_flags(prk, priv_key, BN_FLG_CONSTTIME);
+
+ /* pub_key = g^priv_key mod p */
+ if (!dh->meth->bn_mod_exp(dh, pub_key, dh->params.g, prk, dh->params.p,
+ ctx, mont))
+ goto err;
+ ret = 1;
+err:
+ BN_clear_free(prk);
+ return ret;
}
static int generate_key(DH *dh)
{
int ok = 0;
int generate_new_key = 0;
+#ifndef FIPS_MODE
unsigned l;
+#endif
BN_CTX *ctx = NULL;
- BN_MONT_CTX *mont = NULL;
BIGNUM *pub_key = NULL, *priv_key = NULL;
- if (BN_num_bits(dh->p) > OPENSSL_DH_MAX_MODULUS_BITS) {
- DHerr(DH_F_GENERATE_KEY, DH_R_MODULUS_TOO_LARGE);
+ if (BN_num_bits(dh->params.p) > OPENSSL_DH_MAX_MODULUS_BITS) {
+ DHerr(0, DH_R_MODULUS_TOO_LARGE);
return 0;
}
- if (BN_num_bits(dh->p) < DH_MIN_MODULUS_BITS) {
- DHerr(DH_F_GENERATE_KEY, DH_R_MODULUS_TOO_SMALL);
+ if (BN_num_bits(dh->params.p) < DH_MIN_MODULUS_BITS) {
+ DHerr(0, DH_R_MODULUS_TOO_SMALL);
return 0;
}
- ctx = BN_CTX_new();
+ ctx = BN_CTX_new_ex(dh->libctx);
if (ctx == NULL)
goto err;
if (priv_key == NULL)
goto err;
generate_new_key = 1;
- } else
+ } else {
priv_key = dh->priv_key;
+ }
if (dh->pub_key == NULL) {
pub_key = BN_new();
if (pub_key == NULL)
goto err;
- } else
+ } else {
pub_key = dh->pub_key;
-
- if (dh->flags & DH_FLAG_CACHE_MONT_P) {
- mont = BN_MONT_CTX_set_locked(&dh->method_mont_p,
- dh->lock, dh->p, ctx);
- if (!mont)
- goto err;
}
-
if (generate_new_key) {
- if (dh->q) {
- do {
- if (!BN_priv_rand_range(priv_key, dh->q))
- goto err;
- }
- while (BN_is_zero(priv_key) || BN_is_one(priv_key));
- } else {
- /* secret exponent length */
- l = dh->length ? dh->length : BN_num_bits(dh->p) - 1;
- if (!BN_priv_rand(priv_key, l, BN_RAND_TOP_ONE, BN_RAND_BOTTOM_ANY))
- goto err;
+ /* Is it an approved safe prime ?*/
+ if (DH_get_nid(dh) != NID_undef) {
/*
- * We handle just one known case where g is a quadratic non-residue:
- * for g = 2: p % 8 == 3
+ * The safe prime group code sets N = 2*s
+ * (where s = max security strength supported).
+ * N = dh->length (N = maximum bit length of private key)
*/
- if (BN_is_word(dh->g, DH_GENERATOR_2) && !BN_is_bit_set(dh->p, 2)) {
- /* clear bit 0, since it won't be a secret anyway */
- if (!BN_clear_bit(priv_key, 0))
+ if (dh->params.q == NULL
+ || dh->length > BN_num_bits(dh->params.q))
+ goto err;
+ if (!ffc_generate_private_key(ctx, &dh->params, dh->length,
+ dh->length / 2, priv_key))
+ goto err;
+ } else {
+#ifdef FIPS_MODE
+ if (dh->params.q == NULL)
+ goto err;
+#else
+ if (dh->params.q == NULL) {
+ /* secret exponent length */
+ l = dh->length ? dh->length : BN_num_bits(dh->params.p) - 1;
+ if (!BN_priv_rand_ex(priv_key, l, BN_RAND_TOP_ONE,
+ BN_RAND_BOTTOM_ANY, ctx))
+ goto err;
+ /*
+ * We handle just one known case where g is a quadratic non-residue:
+ * for g = 2: p % 8 == 3
+ */
+ if (BN_is_word(dh->params.g, DH_GENERATOR_2)
+ && !BN_is_bit_set(dh->params.p, 2)) {
+ /* clear bit 0, since it won't be a secret anyway */
+ if (!BN_clear_bit(priv_key, 0))
+ goto err;
+ }
+ } else
+#endif
+ {
+ /*
+ * For FFC FIPS 186-4 keygen
+ * security strength s = 112,
+ * Max Private key size N = len(q)
+ */
+ if (!ffc_generate_private_key(ctx, &dh->params,
+ BN_num_bits(dh->params.q), 112,
+ priv_key))
goto err;
}
}
}
- {
- BIGNUM *prk = BN_new();
-
- if (prk == NULL)
- goto err;
- BN_with_flags(prk, priv_key, BN_FLG_CONSTTIME);
-
- if (!dh->meth->bn_mod_exp(dh, pub_key, dh->g, prk, dh->p, ctx, mont)) {
- BN_clear_free(prk);
- goto err;
- }
- /* We MUST free prk before any further use of priv_key */
- BN_clear_free(prk);
- }
+ if (!dh_generate_public_key(ctx, dh, priv_key, pub_key))
+ goto err;
dh->pub_key = pub_key;
dh->priv_key = priv_key;
ok = 1;
err:
if (ok != 1)
- DHerr(DH_F_GENERATE_KEY, ERR_R_BN_LIB);
+ DHerr(0, ERR_R_BN_LIB);
if (pub_key != dh->pub_key)
BN_free(pub_key);
*pbuf_out = pbuf;
return p_size;
}
-#endif /* FIPS_MODE */