Hide BN_CTX structure details.

[openssl.git] / crypto / dh / dh_key.c

diff --git a/crypto/dh/dh_key.c b/crypto/dh/dh_key.c
index 7576772bcd52635b7fb205a68e82ab00c6ddb15b..91af882e43356860459ddd4a91e6025c405b74c2 100644 (file)
--- a/crypto/dh/dh_key.c
+++ b/crypto/dh/dh_key.c
@@ -58,32 +58,63 @@
 
 #include <stdio.h>
 #include "cryptlib.h"
-#include "bn.h"
-#include "rand.h"
-#include "dh.h"
+#include <openssl/bn.h>
+#include <openssl/rand.h>
+#include <openssl/dh.h>
+#include <openssl/engine.h>
 
-int DH_generate_key(dh)
-DH *dh;
+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 ENGINE_get_DH(dh->engine)->generate_key(dh);
+       }
+
+int DH_compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh)
+       {
+       return ENGINE_get_DH(dh->engine)->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;
-       unsigned int i;
-       BN_CTX *ctx=NULL;
+       BN_CTX *ctx;
+       BN_MONT_CTX *mont;
        BIGNUM *pub_key=NULL,*priv_key=NULL;
 
-       ctx=BN_CTX_new();
+       ctx = BN_CTX_new();
        if (ctx == NULL) goto err;
 
        if (dh->priv_key == NULL)
                {
-               i=dh->length;
-               if (i == 0)
-                       {
-                       /* Make the number p-1 bits long */
-                       i=BN_num_bits(dh->p)-1;
-                       }
                priv_key=BN_new();
                if (priv_key == NULL) goto err;
-               if (!BN_rand(priv_key,i,0,0)) goto err;
+               do
+                       if (!BN_rand_range(priv_key, dh->p)) goto err;
+               while (BN_is_zero(priv_key));
                }
        else
                priv_key=dh->priv_key;
@@ -96,7 +127,17 @@ DH *dh;
        else
                pub_key=dh->pub_key;
 
-       if (!BN_mod_exp(pub_key,dh->g,priv_key,dh->p,ctx)) 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 (!ENGINE_get_DH(dh->engine)->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;
@@ -107,29 +148,37 @@ err:
 
        if ((pub_key != NULL)  && (dh->pub_key == NULL))  BN_free(pub_key);
        if ((priv_key != NULL) && (dh->priv_key == NULL)) BN_free(priv_key);
-       if (ctx != NULL) BN_CTX_free(ctx);
+       BN_CTX_free(ctx);
        return(ok);
        }
 
-int DH_compute_key(key,pub_key,dh)
-unsigned char *key;
-BIGNUM *pub_key;
-DH *dh;
+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();
+       ctx = BN_CTX_new();
        if (ctx == NULL) goto err;
-       tmp=ctx->bn[ctx->tos++];
+       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 (!BN_mod_exp(tmp,pub_key,dh->priv_key,dh->p,ctx))
+       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 (!ENGINE_get_DH(dh->engine)->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;
@@ -137,6 +186,35 @@ DH *dh;
 
        ret=BN_bn2bin(tmp,key);
 err:
-       if (ctx != NULL) BN_CTX_free(ctx);
+       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);
+       }