From: Ben Laurie Date: Sat, 19 Jun 2004 13:16:51 +0000 (+0000) Subject: Add Diffie-Hellman to FIPS. X-Git-Tag: OpenSSL_0_9_7e~83 X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=4d4716dc0309becb174d2ecbcf2b0b4c2969815e;p=openssl Add Diffie-Hellman to FIPS. --- diff --git a/fips/dh/Makefile b/fips/dh/Makefile new file mode 100644 index 0000000000..925810fd74 --- /dev/null +++ b/fips/dh/Makefile @@ -0,0 +1,92 @@ +# +# SSLeay/fips/dh/Makefile +# + +DIR= dh +TOP= ../.. +CC= cc +INCLUDES= +CFLAG=-g +INSTALL_PREFIX= +OPENSSLDIR= /usr/local/ssl +INSTALLTOP=/usr/local/ssl +MAKEDEPPROG= makedepend +MAKEDEPEND= $(TOP)/util/domd $(TOP) -MD $(MAKEDEPPROG) +MAKEFILE= Makefile +AR= ar r + +CFLAGS= $(INCLUDES) $(CFLAG) + +GENERAL=Makefile +TEST= +APPS= + +LIB=$(TOP)/libcrypto.a +LIBSRC=fips_dh_check.c fips_dh_gen.c fips_dh_key.c +LIBOBJ=fips_dh_check.o fips_dh_gen.o fips_dh_key.o + +SRC= $(LIBSRC) + +EXHEADER= +HEADER= $(EXHEADER) + +ALL= $(GENERAL) $(SRC) $(HEADER) + +top: + (cd $(TOP); $(MAKE) DIRS=fips FDIRS=$(DIR) sub_all) + +all: check lib + +lib: $(LIBOBJ) + $(AR) $(LIB) $(LIBOBJ) + $(RANLIB) $(LIB) || echo Never mind. + @sleep 2; touch lib + +check: + TOP=`pwd`/$(TOP) ../fips_check_sha1 fingerprint.sha1 $(SRC) $(HEADER) + +files: + $(PERL) $(TOP)/util/files.pl Makefile >> $(TOP)/MINFO + +links: + @$(PERL) $(TOP)/util/mklink.pl $(TOP)/include/openssl $(EXHEADER) + @$(PERL) $(TOP)/util/mklink.pl $(TOP)/test $(TEST) + @$(PERL) $(TOP)/util/mklink.pl $(TOP)/apps $(APPS) + +install: +# some shells don't like empty lists +# @for i in $(EXHEADER) ; \ +# do \ +# (cp $$i $(INSTALL_PREFIX)$(INSTALLTOP)/include/openssl/$$i; \ +# chmod 644 $(INSTALL_PREFIX)$(INSTALLTOP)/include/openssl/$$i ); \ +# done; + +tags: + ctags $(SRC) + +tests: + +lint: + lint -DLINT $(INCLUDES) $(SRC)>fluff + +depend: + $(MAKEDEPEND) -- $(CFLAG) $(INCLUDES) $(DEPFLAG) -- $(SRC) $(TEST) + +dclean: + $(PERL) -pe 'if (/^# DO NOT DELETE THIS LINE/) {print; exit(0);}' $(MAKEFILE) >Makefile.new + mv -f Makefile.new $(MAKEFILE) + +clean: + rm -f *.o *.obj lib tags core .pure .nfs* *.old *.bak fluff + +# DO NOT DELETE THIS LINE -- make depend depends on it. + +fips_dh_gen.o: ../../include/openssl/bio.h ../../include/openssl/bn.h +fips_dh_gen.o: ../../include/openssl/crypto.h ../../include/openssl/dh.h +fips_dh_gen.o: ../../include/openssl/e_os2.h ../../include/openssl/err.h +fips_dh_gen.o: ../../include/openssl/fips.h ../../include/openssl/lhash.h +fips_dh_gen.o: ../../include/openssl/opensslconf.h +fips_dh_gen.o: ../../include/openssl/opensslv.h +fips_dh_gen.o: ../../include/openssl/ossl_typ.h +fips_dh_gen.o: ../../include/openssl/safestack.h ../../include/openssl/stack.h +fips_dh_gen.o: ../../include/openssl/symhacks.h fips_dh_gen.c diff --git a/fips/dh/fingerprint.sha1 b/fips/dh/fingerprint.sha1 new file mode 100644 index 0000000000..2db86705fe --- /dev/null +++ b/fips/dh/fingerprint.sha1 @@ -0,0 +1,3 @@ +HMAC-SHA1(fips_dh_check.c)= 5657cf7c136f6d9608df40d0699fe1d61d0ad5b5 +HMAC-SHA1(fips_dh_gen.c)= e3626ccd5124942cb19ca962470d2c3704d265bb +HMAC-SHA1(fips_dh_key.c)= 88c882a9063c0b7e5f46de1a7bfa82f71e0a918e diff --git a/fips/dh/fips_dh_check.c b/fips/dh/fips_dh_check.c new file mode 100644 index 0000000000..5b9d8da58b --- /dev/null +++ b/fips/dh/fips_dh_check.c @@ -0,0 +1,119 @@ +/* crypto/dh/dh_check.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 +#include +#include + +/* Check that p is a safe prime and + * if g is 2, 3 or 5, check that is 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 *q=NULL; + + *ret=0; + ctx=BN_CTX_new(); + if (ctx == NULL) goto err; + q=BN_new(); + if (q == NULL) goto err; + + 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(dh->p,BN_prime_checks,NULL,ctx,NULL)) + *ret|=DH_CHECK_P_NOT_PRIME; + else + { + if (!BN_rshift1(q,dh->p)) goto err; + if (!BN_is_prime(q,BN_prime_checks,NULL,ctx,NULL)) + *ret|=DH_CHECK_P_NOT_SAFE_PRIME; + } + ok=1; +err: + if (ctx != NULL) BN_CTX_free(ctx); + if (q != NULL) BN_free(q); + return(ok); + } diff --git a/fips/dh/fips_dh_gen.c b/fips/dh/fips_dh_gen.c new file mode 100644 index 0000000000..db5b2910f4 --- /dev/null +++ b/fips/dh/fips_dh_gen.c @@ -0,0 +1,182 @@ +/* crypto/dh/dh_gen.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 +#include +#include +#include +#include +#include + +/* We generate DH parameters as follows + * find a prime q which is prime_len/2 bits long. + * p=(2*q)+1 or (p-1)/2 = q + * For this case, g is a generator if + * g^((p-1)/q) mod p != 1 for values of q which are the factors of p-1. + * Since the factors of p-1 are q and 2, we just need to check + * g^2 mod p != 1 and g^q mod p != 1. + * + * Having said all that, + * there is another special case method for the generators 2, 3 and 5. + * for 2, p mod 24 == 11 + * for 3, p mod 12 == 5 <<<<< does not work for safe primes. + * for 5, p mod 10 == 3 or 7 + * + * Thanks to Phil Karn for the pointers about the + * special generators and for answering some of my questions. + * + * I've implemented the second simple method :-). + * Since DH should be using a safe prime (both p and q are prime), + * this generator function can take a very very long time to run. + */ +/* Actually there is no reason to insist that 'generator' be a generator. + * It's just as OK (and in some sense better) to use a generator of the + * order-q subgroup. + */ + +#ifdef OPENSSL_FIPS + +DH *DH_generate_parameters(int prime_len, int generator, + void (*callback)(int,int,void *), void *cb_arg) + { + BIGNUM *p=NULL,*t1,*t2; + DH *ret=NULL; + int g,ok= -1; + BN_CTX *ctx=NULL; + + if(FIPS_selftest_fail) + { + FIPSerr(FIPS_F_DH_GENERATE_PARAMETERS,FIPS_R_FIPS_SELFTEST_FAILED); + return NULL; + } + + ret=DH_new(); + if (ret == NULL) goto err; + ctx=BN_CTX_new(); + if (ctx == NULL) goto err; + BN_CTX_start(ctx); + t1 = BN_CTX_get(ctx); + t2 = BN_CTX_get(ctx); + if (t1 == NULL || t2 == NULL) goto err; + + if (generator <= 1) + { + DHerr(DH_F_DH_GENERATE_PARAMETERS, DH_R_BAD_GENERATOR); + goto err; + } + if (generator == DH_GENERATOR_2) + { + if (!BN_set_word(t1,24)) goto err; + if (!BN_set_word(t2,11)) goto err; + g=2; + } +#if 0 /* does not work for safe primes */ + else if (generator == DH_GENERATOR_3) + { + if (!BN_set_word(t1,12)) goto err; + if (!BN_set_word(t2,5)) goto err; + g=3; + } +#endif + else if (generator == DH_GENERATOR_5) + { + if (!BN_set_word(t1,10)) goto err; + if (!BN_set_word(t2,3)) goto err; + /* BN_set_word(t3,7); just have to miss + * out on these ones :-( */ + g=5; + } + else + { + /* in the general case, don't worry if 'generator' is a + * generator or not: since we are using safe primes, + * it will generate either an order-q or an order-2q group, + * which both is OK */ + if (!BN_set_word(t1,2)) goto err; + if (!BN_set_word(t2,1)) goto err; + g=generator; + } + + p=BN_generate_prime(NULL,prime_len,1,t1,t2,callback,cb_arg); + if (p == NULL) goto err; + if (callback != NULL) callback(3,0,cb_arg); + ret->p=p; + ret->g=BN_new(); + if (!BN_set_word(ret->g,g)) goto err; + ok=1; +err: + if (ok == -1) + { + DHerr(DH_F_DH_GENERATE_PARAMETERS,ERR_R_BN_LIB); + ok=0; + } + + if (ctx != NULL) + { + BN_CTX_end(ctx); + BN_CTX_free(ctx); + } + if (!ok && (ret != NULL)) + { + DH_free(ret); + ret=NULL; + } + return(ret); + } + +#endif diff --git a/fips/dh/fips_dh_key.c b/fips/dh/fips_dh_key.c new file mode 100644 index 0000000000..447d5b3841 --- /dev/null +++ b/fips/dh/fips_dh_key.c @@ -0,0 +1,222 @@ +/* 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 +#include +#include +#include +#include + +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); + } + +int DH_compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh) + { + return dh->meth->compute_key(key, pub_key, dh); + } + +static DH_METHOD dh_ossl = { +"OpenSSL DH Method", +generate_key, +compute_key, +dh_bn_mod_exp, +dh_init, +dh_finish, +0, +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; + 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->method_mont_p == NULL) && (dh->flags & DH_FLAG_CACHE_MONT_P)) + { + if ((dh->method_mont_p=(char *)BN_MONT_CTX_new()) != NULL) + if (!BN_MONT_CTX_set((BN_MONT_CTX *)dh->method_mont_p, + dh->p,ctx)) goto err; + } + mont=(BN_MONT_CTX *)dh->method_mont_p; + + if (generate_new_key) + { + l = dh->length ? dh->length : BN_num_bits(dh->p)-1; /* secret exponent length */ + if (!BN_rand(priv_key, l, 0, 0)) goto err; + } + if (!dh->meth->bn_mod_exp(dh, pub_key, dh->g, priv_key,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_DH_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; + BN_MONT_CTX *mont; + BIGNUM *tmp; + int ret= -1; + + 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_DH_COMPUTE_KEY,DH_R_NO_PRIVATE_VALUE); + goto err; + } + if ((dh->method_mont_p == NULL) && (dh->flags & DH_FLAG_CACHE_MONT_P)) + { + if ((dh->method_mont_p=(char *)BN_MONT_CTX_new()) != NULL) + if (!BN_MONT_CTX_set((BN_MONT_CTX *)dh->method_mont_p, + dh->p,ctx)) goto err; + } + + mont=(BN_MONT_CTX *)dh->method_mont_p; + if (!dh->meth->bn_mod_exp(dh, tmp, pub_key, dh->priv_key,dh->p,ctx,mont)) + { + DHerr(DH_F_DH_COMPUTE_KEY,ERR_R_BN_LIB); + goto err; + } + + ret=BN_bn2bin(tmp,key); +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) + { + if (a->top == 1) + { + 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((BN_MONT_CTX *)dh->method_mont_p); + return(1); + }