1 /* crypto/engine/engine_openssl.c */
2 /* Written by Geoff Thorpe (geoff@geoffthorpe.net) for the OpenSSL
5 /* ====================================================================
6 * Copyright (c) 1999 The OpenSSL Project. All rights reserved.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in
17 * the documentation and/or other materials provided with the
20 * 3. All advertising materials mentioning features or use of this
21 * software must display the following acknowledgment:
22 * "This product includes software developed by the OpenSSL Project
23 * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
25 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
26 * endorse or promote products derived from this software without
27 * prior written permission. For written permission, please contact
28 * licensing@OpenSSL.org.
30 * 5. Products derived from this software may not be called "OpenSSL"
31 * nor may "OpenSSL" appear in their names without prior written
32 * permission of the OpenSSL Project.
34 * 6. Redistributions of any form whatsoever must retain the following
36 * "This product includes software developed by the OpenSSL Project
37 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
39 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
40 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
41 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
42 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
43 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
45 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
46 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
48 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
49 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
50 * OF THE POSSIBILITY OF SUCH DAMAGE.
51 * ====================================================================
53 * This product includes cryptographic software written by Eric Young
54 * (eay@cryptsoft.com). This product includes software written by Tim
55 * Hudson (tjh@cryptsoft.com).
61 #include <openssl/crypto.h>
63 #include "engine_int.h"
64 #include <openssl/engine.h>
65 #include <openssl/dso.h>
66 #include <openssl/rsa.h>
67 #include <openssl/dsa.h>
68 #include <openssl/dh.h>
69 #include <openssl/rand.h>
70 #include <openssl/bn.h>
72 /* This is the only function we need to implement as OpenSSL
73 * doesn't have a native CRT mod_exp. Perhaps this should be
74 * BN_mod_exp_crt and moved into crypto/bn/ ?? ... dunno. */
75 static int openssl_mod_exp_crt(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
76 const BIGNUM *q, const BIGNUM *dmp1, const BIGNUM *dmq1,
77 const BIGNUM *iqmp, BN_CTX *ctx);
79 /* The ENGINE structure that can be pointed to. */
80 static ENGINE engine_openssl =
83 "Software default engine support",
86 NULL, /* these methods are "stolen" in ENGINE_openssl() */
91 NULL, /* no finish() */
93 NULL, /* no load_privkey() */
94 NULL, /* no load_pubkey() */
96 0, 0, /* no references. */
97 NULL, NULL /* unlinked */
100 /* As this is only ever called once, there's no need for locking
101 * (indeed - the lock will already be held by our caller!!!) */
102 ENGINE *ENGINE_openssl()
104 /* We need to populate our structure with the software pointers
105 * that we want to steal. */
106 engine_openssl.rsa_meth = RSA_get_default_openssl_method();
107 engine_openssl.dsa_meth = DSA_get_default_openssl_method();
108 engine_openssl.dh_meth = DH_get_default_openssl_method();
109 engine_openssl.rand_meth = RAND_SSLeay();
110 engine_openssl.bn_mod_exp = BN_mod_exp;
111 return &engine_openssl;
114 /* Chinese Remainder Theorem, taken and adapted from rsa_eay.c */
115 static int openssl_mod_exp_crt(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
116 const BIGNUM *q, const BIGNUM *dmp1,
117 const BIGNUM *dmq1, const BIGNUM *iqmp, BN_CTX *ctx)
122 BIGNUM *temp_bn = NULL;
127 if ((bn_ctx=BN_CTX_new()) == NULL) goto err;
130 /* BN_mul() cannot accept const BIGNUMs so I use the BN_CTX
131 * to duplicate what I need. <sigh> */
132 BN_CTX_start(bn_ctx);
133 if ((temp_bn = BN_CTX_get(bn_ctx)) == NULL) goto err;
134 if (!BN_copy(temp_bn, iqmp)) goto err;
136 if (!BN_mod(&r1, a, q, bn_ctx)) goto err;
137 if (!engine_openssl.bn_mod_exp(&m1, &r1, dmq1, q, bn_ctx))
140 if (!BN_mod(&r1, a, p, bn_ctx)) goto err;
141 if (!engine_openssl.bn_mod_exp(r, &r1, dmp1, p, bn_ctx))
144 if (!BN_sub(r, r, &m1)) goto err;
145 /* This will help stop the size of r0 increasing, which does
146 * affect the multiply if it optimised for a power of 2 size */
148 if (!BN_add(r, r, p)) goto err;
150 if (!BN_mul(&r1, r, temp_bn, bn_ctx)) goto err;
151 if (!BN_mod(r, &r1, p, bn_ctx)) goto err;
152 /* If p < q it is occasionally possible for the correction of
153 * adding 'p' if r is negative above to leave the result still
154 * negative. This can break the private key operations: the following
155 * second correction should *always* correct this rare occurrence.
156 * This will *never* happen with OpenSSL generated keys because
157 * they ensure p > q [steve]
160 if (!BN_add(r, r, p)) goto err;
161 /* Again, BN_mul() will need non-const values. */
162 if (!BN_copy(temp_bn, q)) goto err;
163 if (!BN_mul(&r1, r, temp_bn, bn_ctx)) goto err;
164 if (!BN_add(r, &r1, &m1)) goto err;