components/openssl/openssl-fips/inline-t4/dh_check.c
changeset 7362 8875826c2bcb
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/components/openssl/openssl-fips/inline-t4/dh_check.c	Sat Nov 19 19:35:47 2016 -0800
@@ -0,0 +1,187 @@
+/* crypto/dh/dh_check.c */
+/* Copyright (C) 1995-1998 Eric Young ([email protected])
+ * All rights reserved.
+ *
+ * This package is an SSL implementation written
+ * by Eric Young ([email protected]).
+ * The implementation was written so as to conform with Netscapes SSL.
+ *
+ * This library is free for commercial and non-commercial use as long as
+ * the following conditions are aheared to.  The following conditions
+ * apply to all code found in this distribution, be it the RC4, RSA,
+ * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
+ * included with this distribution is covered by the same copyright terms
+ * except that the holder is Tim Hudson ([email protected]).
+ *
+ * Copyright remains Eric Young's, and as such any Copyright notices in
+ * the code are not to be removed.
+ * If this package is used in a product, Eric Young should be given attribution
+ * as the author of the parts of the library used.
+ * This can be in the form of a textual message at program startup or
+ * in documentation (online or textual) provided with the package.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *    "This product includes cryptographic software written by
+ *     Eric Young ([email protected])"
+ *    The word 'cryptographic' can be left out if the rouines from the library
+ *    being used are not cryptographic related :-).
+ * 4. If you include any Windows specific code (or a derivative thereof) from
+ *    the apps directory (application code) you must include an acknowledgement:
+ *    "This product includes software written by Tim Hudson ([email protected])"
+ *
+ * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * The licence and distribution terms for any publically available version or
+ * derivative of this code cannot be changed.  i.e. this code cannot simply be
+ * copied and put under another distribution licence
+ * [including the GNU Public Licence.]
+ */
+
+#include <stdio.h>
+#include "cryptlib.h"
+#include <openssl/bn.h>
+#include <openssl/dh.h>
+
+/*-
+ * Check that p is a safe prime and
+ * if g is 2, 3 or 5, check that it is a suitable generator
+ * where
+ * for 2, p mod 24 == 11
+ * for 3, p mod 12 == 5
+ * for 5, p mod 10 == 3 or 7
+ * should hold.
+ */
+
+int DH_check(const DH *dh, int *ret)
+{
+    int ok = 0;
+    BN_CTX *ctx = NULL;
+    BN_ULONG l;
+    BIGNUM *t1 = NULL, *t2 = NULL;
+
+    *ret = 0;
+    ctx = BN_CTX_new();
+    if (ctx == NULL)
+        goto err;
+    BN_CTX_start(ctx);
+    t1 = BN_CTX_get(ctx);
+    if (t1 == NULL)
+        goto err;
+    t2 = BN_CTX_get(ctx);
+    if (t2 == NULL)
+        goto err;
+
+    if (dh->q) {
+        if (BN_cmp(dh->g, BN_value_one()) <= 0)
+            *ret |= DH_NOT_SUITABLE_GENERATOR;
+        else if (BN_cmp(dh->g, dh->p) >= 0)
+            *ret |= DH_NOT_SUITABLE_GENERATOR;
+        else {
+            /* Check g^q == 1 mod p */
+            if (!BN_mod_exp(t1, dh->g, dh->q, dh->p, ctx))
+                goto err;
+            if (!BN_is_one(t1))
+                *ret |= DH_NOT_SUITABLE_GENERATOR;
+        }
+        if (!BN_is_prime_ex(dh->q, BN_prime_checks, ctx, NULL))
+            *ret |= DH_CHECK_P_NOT_SAFE_PRIME;
+        /* Check p == 1 mod q  i.e. q divides p - 1 */
+        if (!BN_div(t1, t2, dh->p, dh->q, ctx))
+            goto err;
+        if (!BN_is_one(t2))
+            *ret |= DH_CHECK_P_NOT_SAFE_PRIME;
+        if (dh->j && BN_cmp(dh->j, t1))
+            *ret |= DH_CHECK_P_NOT_SAFE_PRIME;
+
+    } else if (BN_is_word(dh->g, DH_GENERATOR_2)) {
+        l = BN_mod_word(dh->p, 24);
+        if (l != 11)
+            *ret |= DH_NOT_SUITABLE_GENERATOR;
+    }
+#if 0
+    else if (BN_is_word(dh->g, DH_GENERATOR_3)) {
+        l = BN_mod_word(dh->p, 12);
+        if (l != 5)
+            *ret |= DH_NOT_SUITABLE_GENERATOR;
+    }
+#endif
+    else if (BN_is_word(dh->g, DH_GENERATOR_5)) {
+        l = BN_mod_word(dh->p, 10);
+        if ((l != 3) && (l != 7))
+            *ret |= DH_NOT_SUITABLE_GENERATOR;
+    } else
+        *ret |= DH_UNABLE_TO_CHECK_GENERATOR;
+
+    if (!BN_is_prime_ex(dh->p, BN_prime_checks, ctx, NULL))
+        *ret |= DH_CHECK_P_NOT_PRIME;
+    else if (!dh->q) {
+        if (!BN_rshift1(t1, dh->p))
+            goto err;
+        if (!BN_is_prime_ex(t1, BN_prime_checks, ctx, NULL))
+            *ret |= DH_CHECK_P_NOT_SAFE_PRIME;
+    }
+    ok = 1;
+ err:
+    if (ctx != NULL) {
+        BN_CTX_end(ctx);
+        BN_CTX_free(ctx);
+    }
+    return (ok);
+}
+
+int DH_check_pub_key(const DH *dh, const BIGNUM *pub_key, int *ret)
+{
+    int ok = 0;
+    BIGNUM *tmp = NULL;
+    BN_CTX *ctx = NULL;
+
+    *ret = 0;
+    ctx = BN_CTX_new();
+    if (ctx == NULL)
+        goto err;
+    BN_CTX_start(ctx);
+    tmp = BN_CTX_get(ctx);
+    if (tmp == NULL || !BN_set_word(tmp, 1))
+        goto err;
+    if (BN_cmp(pub_key, tmp) <= 0)
+        *ret |= DH_CHECK_PUBKEY_TOO_SMALL;
+    if (BN_copy(tmp, dh->p) == NULL || !BN_sub_word(tmp, 1))
+        goto err;
+    if (BN_cmp(pub_key, tmp) >= 0)
+        *ret |= DH_CHECK_PUBKEY_TOO_LARGE;
+
+    if (dh->q != NULL) {
+        /* Check pub_key^q == 1 mod p */
+        if (!BN_mod_exp(tmp, pub_key, dh->q, dh->p, ctx))
+            goto err;
+        if (!BN_is_one(tmp))
+            *ret |= DH_CHECK_PUBKEY_TOO_LARGE;
+    }
+
+    ok = 1;
+ err:
+    if (ctx != NULL) {
+        BN_CTX_end(ctx);
+        BN_CTX_free(ctx);
+    }
+    return (ok);
+}