aboutsummaryrefslogtreecommitdiffstats
path: root/contrib/libs/openssl/crypto/dh/dh_key.c
diff options
context:
space:
mode:
authorDevtools Arcadia <arcadia-devtools@yandex-team.ru>2022-02-07 18:08:42 +0300
committerDevtools Arcadia <arcadia-devtools@mous.vla.yp-c.yandex.net>2022-02-07 18:08:42 +0300
commit1110808a9d39d4b808aef724c861a2e1a38d2a69 (patch)
treee26c9fed0de5d9873cce7e00bc214573dc2195b7 /contrib/libs/openssl/crypto/dh/dh_key.c
downloadydb-1110808a9d39d4b808aef724c861a2e1a38d2a69.tar.gz
intermediate changes
ref:cde9a383711a11544ce7e107a78147fb96cc4029
Diffstat (limited to 'contrib/libs/openssl/crypto/dh/dh_key.c')
-rw-r--r--contrib/libs/openssl/crypto/dh/dh_key.c266
1 files changed, 266 insertions, 0 deletions
diff --git a/contrib/libs/openssl/crypto/dh/dh_key.c b/contrib/libs/openssl/crypto/dh/dh_key.c
new file mode 100644
index 0000000000..117f2fa883
--- /dev/null
+++ b/contrib/libs/openssl/crypto/dh/dh_key.c
@@ -0,0 +1,266 @@
+/*
+ * Copyright 1995-2021 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the OpenSSL license (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
+ */
+
+#include <stdio.h>
+#include "internal/cryptlib.h"
+#include "dh_local.h"
+#include "crypto/bn.h"
+
+static int generate_key(DH *dh);
+static int compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh);
+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_generate_key(DH *dh)
+{
+ return dh->meth->generate_key(dh);
+}
+
+/*-
+ * NB: This function is inherently not constant time due to the
+ * RFC 5246 (8.1.2) padding style that strips leading zero bytes.
+ */
+int DH_compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh)
+{
+ int ret = 0, i;
+ volatile size_t npad = 0, mask = 1;
+
+ /* compute the key; ret is constant unless compute_key is external */
+ if ((ret = dh->meth->compute_key(key, pub_key, dh)) <= 0)
+ return ret;
+
+ /* count leading zero bytes, yet still touch all bytes */
+ for (i = 0; i < ret; i++) {
+ mask &= !key[i];
+ npad += mask;
+ }
+
+ /* unpad key */
+ ret -= npad;
+ /* key-dependent memory access, potentially leaking npad / ret */
+ memmove(key, key + npad, ret);
+ /* key-dependent memory access, potentially leaking npad / ret */
+ memset(key + ret, 0, npad);
+
+ return ret;
+}
+
+int DH_compute_key_padded(unsigned char *key, const BIGNUM *pub_key, DH *dh)
+{
+ int rv, pad;
+
+ /* rv is constant unless compute_key is external */
+ rv = dh->meth->compute_key(key, pub_key, dh);
+ if (rv <= 0)
+ return rv;
+ pad = BN_num_bytes(dh->p) - rv;
+ /* pad is constant (zero) unless compute_key is external */
+ if (pad > 0) {
+ memmove(key + pad, key, rv);
+ memset(key, 0, pad);
+ }
+ return rv + pad;
+}
+
+static DH_METHOD dh_ossl = {
+ "OpenSSL DH Method",
+ generate_key,
+ compute_key,
+ dh_bn_mod_exp,
+ dh_init,
+ dh_finish,
+ DH_FLAG_FIPS_METHOD,
+ NULL,
+ NULL
+};
+
+static const DH_METHOD *default_DH_method = &dh_ossl;
+
+const DH_METHOD *DH_OpenSSL(void)
+{
+ return &dh_ossl;
+}
+
+void DH_set_default_method(const DH_METHOD *meth)
+{
+ default_DH_method = meth;
+}
+
+const DH_METHOD *DH_get_default_method(void)
+{
+ return default_DH_method;
+}
+
+static int generate_key(DH *dh)
+{
+ int ok = 0;
+ int generate_new_key = 0;
+ unsigned l;
+ 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);
+ return 0;
+ }
+
+ ctx = BN_CTX_new();
+ if (ctx == NULL)
+ goto err;
+
+ if (dh->priv_key == NULL) {
+ priv_key = BN_secure_new();
+ if (priv_key == NULL)
+ goto err;
+ generate_new_key = 1;
+ } else
+ priv_key = dh->priv_key;
+
+ if (dh->pub_key == NULL) {
+ pub_key = BN_new();
+ if (pub_key == NULL)
+ goto err;
+ } 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;
+ /*
+ * We handle just one known case where g is a quadratic non-residue:
+ * for g = 2: p % 8 == 3
+ */
+ 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))
+ 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);
+ }
+
+ 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);
+
+ if (pub_key != dh->pub_key)
+ BN_free(pub_key);
+ if (priv_key != dh->priv_key)
+ BN_free(priv_key);
+ BN_CTX_free(ctx);
+ return ok;
+}
+
+static int compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh)
+{
+ BN_CTX *ctx = NULL;
+ BN_MONT_CTX *mont = NULL;
+ BIGNUM *tmp;
+ int ret = -1;
+ int check_result;
+
+ if (BN_num_bits(dh->p) > OPENSSL_DH_MAX_MODULUS_BITS) {
+ DHerr(DH_F_COMPUTE_KEY, DH_R_MODULUS_TOO_LARGE);
+ goto err;
+ }
+
+ ctx = BN_CTX_new();
+ if (ctx == NULL)
+ goto err;
+ BN_CTX_start(ctx);
+ tmp = BN_CTX_get(ctx);
+ if (tmp == NULL)
+ goto err;
+
+ if (dh->priv_key == NULL) {
+ DHerr(DH_F_COMPUTE_KEY, DH_R_NO_PRIVATE_VALUE);
+ goto err;
+ }
+
+ if (dh->flags & DH_FLAG_CACHE_MONT_P) {
+ mont = BN_MONT_CTX_set_locked(&dh->method_mont_p,
+ dh->lock, dh->p, ctx);
+ BN_set_flags(dh->priv_key, BN_FLG_CONSTTIME);
+ if (!mont)
+ goto err;
+ }
+
+ if (!DH_check_pub_key(dh, pub_key, &check_result) || check_result) {
+ DHerr(DH_F_COMPUTE_KEY, DH_R_INVALID_PUBKEY);
+ goto err;
+ }
+
+ if (!dh->
+ meth->bn_mod_exp(dh, tmp, pub_key, dh->priv_key, dh->p, ctx, mont)) {
+ DHerr(DH_F_COMPUTE_KEY, ERR_R_BN_LIB);
+ goto err;
+ }
+
+ ret = BN_bn2binpad(tmp, key, BN_num_bytes(dh->p));
+ err:
+ BN_CTX_end(ctx);
+ BN_CTX_free(ctx);
+ return ret;
+}
+
+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)
+{
+ return BN_mod_exp_mont(r, a, p, m, ctx, m_ctx);
+}
+
+static int dh_init(DH *dh)
+{
+ dh->flags |= DH_FLAG_CACHE_MONT_P;
+ return 1;
+}
+
+static int dh_finish(DH *dh)
+{
+ BN_MONT_CTX_free(dh->method_mont_p);
+ return 1;
+}