diff options
Diffstat (limited to 'thirdparty/openssl/crypto/dh/dh_key.c')
-rw-r--r-- | thirdparty/openssl/crypto/dh/dh_key.c | 289 |
1 files changed, 289 insertions, 0 deletions
diff --git a/thirdparty/openssl/crypto/dh/dh_key.c b/thirdparty/openssl/crypto/dh/dh_key.c new file mode 100644 index 0000000000..1d80fb2c5f --- /dev/null +++ b/thirdparty/openssl/crypto/dh/dh_key.c @@ -0,0 +1,289 @@ +/* crypto/dh/dh_key.c */ +/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) + * All rights reserved. + * + * This package is an SSL implementation written + * by Eric Young (eay@cryptsoft.com). + * 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 (tjh@cryptsoft.com). + * + * 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 (eay@cryptsoft.com)" + * 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 (tjh@cryptsoft.com)" + * + * 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/rand.h> +#include <openssl/dh.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) +{ +#ifdef OPENSSL_FIPS + if (FIPS_mode() && !(dh->meth->flags & DH_FLAG_FIPS_METHOD) + && !(dh->flags & DH_FLAG_NON_FIPS_ALLOW)) { + DHerr(DH_F_DH_GENERATE_KEY, DH_R_NON_FIPS_METHOD); + return 0; + } +#endif + return dh->meth->generate_key(dh); +} + +int DH_compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh) +{ +#ifdef OPENSSL_FIPS + if (FIPS_mode() && !(dh->meth->flags & DH_FLAG_FIPS_METHOD) + && !(dh->flags & DH_FLAG_NON_FIPS_ALLOW)) { + DHerr(DH_F_DH_COMPUTE_KEY, DH_R_NON_FIPS_METHOD); + return 0; + } +#endif + return dh->meth->compute_key(key, pub_key, dh); +} + +int DH_compute_key_padded(unsigned char *key, const BIGNUM *pub_key, DH *dh) +{ + int rv, pad; + rv = dh->meth->compute_key(key, pub_key, dh); + if (rv <= 0) + return rv; + pad = BN_num_bytes(dh->p) - rv; + 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, + 0, + NULL, + NULL +}; + +const DH_METHOD *DH_OpenSSL(void) +{ + return &dh_ossl; +} + +static int generate_key(DH *dh) +{ + int ok = 0; + int generate_new_key = 0; + unsigned l; + BN_CTX *ctx; + BN_MONT_CTX *mont = NULL; + BIGNUM *pub_key = NULL, *priv_key = NULL; + + ctx = BN_CTX_new(); + if (ctx == NULL) + goto err; + + if (dh->priv_key == NULL) { + priv_key = BN_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, + CRYPTO_LOCK_DH, dh->p, ctx); + if (!mont) + goto err; + } + + if (generate_new_key) { + if (dh->q) { + do { + if (!BN_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_rand(priv_key, l, 0, 0)) + goto err; + } + } + + { + BIGNUM local_prk; + BIGNUM *prk; + + if ((dh->flags & DH_FLAG_NO_EXP_CONSTTIME) == 0) { + BN_init(&local_prk); + prk = &local_prk; + BN_with_flags(prk, priv_key, BN_FLG_CONSTTIME); + } else + prk = priv_key; + + if (!dh->meth->bn_mod_exp(dh, pub_key, dh->g, prk, dh->p, ctx, mont)) + 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); + + if ((pub_key != NULL) && (dh->pub_key == NULL)) + BN_free(pub_key); + if ((priv_key != NULL) && (dh->priv_key == NULL)) + 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 (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, + CRYPTO_LOCK_DH, dh->p, ctx); + if ((dh->flags & DH_FLAG_NO_EXP_CONSTTIME) == 0) { + /* XXX */ + 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_bn2bin(tmp, key); + err: + if (ctx != NULL) { + 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) +{ + /* + * If a is only one word long and constant time is false, use the faster + * exponenentiation function. + */ + if (a->top == 1 && ((dh->flags & DH_FLAG_NO_EXP_CONSTTIME) != 0)) { + BN_ULONG A = a->d[0]; + return BN_mod_exp_mont_word(r, A, p, m, ctx, m_ctx); + } else + 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) +{ + if (dh->method_mont_p) + BN_MONT_CTX_free(dh->method_mont_p); + return (1); +} |