Don't allocate r/s in DSA_SIG and ECDSA_SIG
[openssl.git] / crypto / dsa / dsa_gen.c
index 861ff90e5d243c28fa21f99206685453541b227f..3dac5500312afe1e321247685630a3533b58c66e 100644 (file)
-/* crypto/dsa/dsa_gen.c */
-/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
- * All rights reserved.
+/*
+ * Copyright 1995-2016 The OpenSSL Project Authors. 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.]
+ * Licensed under the OpenSSL license (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
  */
 
-#undef GENUINE_DSA
-
-#ifdef GENUINE_DSA
-/* Parameter generation follows the original release of FIPS PUB 186,
- * Appendix 2.2 (i.e. use SHA as defined in FIPS PUB 180) */
-#define HASH    EVP_sha()
-#else
-/* Parameter generation follows the updated Appendix 2.2 for FIPS PUB 186,
- * also Appendix 2.2 of FIPS PUB 186-1 (i.e. use SHA as defined in
- * FIPS PUB 180-1) */
-#define HASH    EVP_sha1()
-#endif 
-
-#include <openssl/opensslconf.h> /* To see if OPENSSL_NO_SHA is defined */
-
-#ifndef OPENSSL_NO_SHA
-
-
+/*
+ * Parameter generation follows the updated Appendix 2.2 for FIPS PUB 186,
+ * also Appendix 2.2 of FIPS PUB 186-1 (i.e. use SHA as defined in FIPS PUB
+ * 180-1)
+ */
+#define xxxHASH    EVP_sha1()
 
+#include <openssl/opensslconf.h>
 #include <stdio.h>
-#include "cryptlib.h"
+#include "internal/cryptlib.h"
 #include <openssl/evp.h>
 #include <openssl/bn.h>
 #include <openssl/rand.h>
 #include <openssl/sha.h>
-
 #include "dsa_locl.h"
 
 int DSA_generate_parameters_ex(DSA *ret, int bits,
-               const unsigned char *seed_in, int seed_len,
-               int *counter_ret, unsigned long *h_ret, BN_GENCB *cb)
-       {
-       if(ret->meth->dsa_paramgen)
-               return ret->meth->dsa_paramgen(ret, bits, seed_in, seed_len,
-                               counter_ret, h_ret, cb);
-       else
-               {
-               const EVP_MD *evpmd;
-               size_t qbits = bits >= 2048 ? 256 : 160;
-
-               if (bits >= 2048)
-                       {
-                       qbits = 256;
-                       evpmd = EVP_sha256();
-                       }
-               else
-                       {
-                       qbits = 160;
-                       evpmd = EVP_sha1();
-                       }
-
-               return dsa_builtin_paramgen(ret, bits, qbits, evpmd,
-                       seed_in, seed_len, NULL, counter_ret, h_ret, cb);
-               }
-       }
+                               const unsigned char *seed_in, int seed_len,
+                               int *counter_ret, unsigned long *h_ret,
+                               BN_GENCB *cb)
+{
+    if (ret->meth->dsa_paramgen)
+        return ret->meth->dsa_paramgen(ret, bits, seed_in, seed_len,
+                                       counter_ret, h_ret, cb);
+    else {
+        const EVP_MD *evpmd = bits >= 2048 ? EVP_sha256() : EVP_sha1();
+        size_t qbits = EVP_MD_size(evpmd) * 8;
+
+        return dsa_builtin_paramgen(ret, bits, qbits, evpmd,
+                                    seed_in, seed_len, NULL, counter_ret,
+                                    h_ret, cb);
+    }
+}
 
 int dsa_builtin_paramgen(DSA *ret, size_t bits, size_t qbits,
-       const EVP_MD *evpmd, const unsigned char *seed_in, size_t seed_len,
-       unsigned char *seed_out,
-       int *counter_ret, unsigned long *h_ret, BN_GENCB *cb)
-       {
-       int ok=0;
-       unsigned char seed[SHA256_DIGEST_LENGTH];
-       unsigned char md[SHA256_DIGEST_LENGTH];
-       unsigned char buf[SHA256_DIGEST_LENGTH],buf2[SHA256_DIGEST_LENGTH];
-       BIGNUM *r0,*W,*X,*c,*test;
-       BIGNUM *g=NULL,*q=NULL,*p=NULL;
-       BN_MONT_CTX *mont=NULL;
-       int i, k, n=0, m=0, qsize = qbits >> 3;
-       int counter=0;
-       int r=0;
-       BN_CTX *ctx=NULL;
-       unsigned int h=2;
-
-       if (qsize != SHA_DIGEST_LENGTH && qsize != SHA224_DIGEST_LENGTH &&
-           qsize != SHA256_DIGEST_LENGTH)
-               /* invalid q size */
-               return 0;
-
-       if (evpmd == NULL)
-               /* use SHA1 as default */
-               evpmd = EVP_sha1();
-
-       if (bits < 512)
-               bits = 512;
-
-       bits = (bits+63)/64*64;
-
-       /* NB: seed_len == 0 is special case: copy generated seed to
-        * seed_in if it is not NULL.
-        */
-       if (seed_len && (seed_len < (size_t)qsize))
-               seed_in = NULL;         /* seed buffer too small -- ignore */
-       if (seed_len > (size_t)qsize) 
-               seed_len = qsize;       /* App. 2.2 of FIPS PUB 186 allows larger SEED,
-                                        * but our internal buffers are restricted to 160 bits*/
-       if (seed_in != NULL)
-               memcpy(seed, seed_in, seed_len);
-
-       if ((ctx=BN_CTX_new()) == NULL)
-               goto err;
-
-       if ((mont=BN_MONT_CTX_new()) == NULL)
-               goto err;
-
-       BN_CTX_start(ctx);
-       r0 = BN_CTX_get(ctx);
-       g = BN_CTX_get(ctx);
-       W = BN_CTX_get(ctx);
-       q = BN_CTX_get(ctx);
-       X = BN_CTX_get(ctx);
-       c = BN_CTX_get(ctx);
-       p = BN_CTX_get(ctx);
-       test = BN_CTX_get(ctx);
-
-       if (!BN_lshift(test,BN_value_one(),bits-1))
-               goto err;
-
-       for (;;)
-               {
-               for (;;) /* find q */
-                       {
-                       int seed_is_random;
-
-                       /* step 1 */
-                       if(!BN_GENCB_call(cb, 0, m++))
-                               goto err;
-
-                       if (!seed_len)
-                               {
-                               if (RAND_pseudo_bytes(seed, qsize) < 0)
-                                       goto err;
-                               seed_is_random = 1;
-                               }
-                       else
-                               {
-                               seed_is_random = 0;
-                               seed_len=0; /* use random seed if 'seed_in' turns out to be bad*/
-                               }
-                       memcpy(buf , seed, qsize);
-                       memcpy(buf2, seed, qsize);
-                       /* precompute "SEED + 1" for step 7: */
-                       for (i = qsize-1; i >= 0; i--)
-                               {
-                               buf[i]++;
-                               if (buf[i] != 0)
-                                       break;
-                               }
-
-                       /* step 2 */
-                       if (!EVP_Digest(seed, qsize, md,   NULL, evpmd, NULL))
-                               goto err;
-                       if (!EVP_Digest(buf,  qsize, buf2, NULL, evpmd, NULL))
-                               goto err;
-                       for (i = 0; i < qsize; i++)
-                               md[i]^=buf2[i];
-
-                       /* step 3 */
-                       md[0] |= 0x80;
-                       md[qsize-1] |= 0x01;
-                       if (!BN_bin2bn(md, qsize, q))
-                               goto err;
-
-                       /* step 4 */
-                       r = BN_is_prime_fasttest_ex(q, DSS_prime_checks, ctx,
-                                       seed_is_random, cb);
-                       if (r > 0)
-                               break;
-                       if (r != 0)
-                               goto err;
-
-                       /* do a callback call */
-                       /* step 5 */
-                       }
-
-               if(!BN_GENCB_call(cb, 2, 0)) goto err;
-               if(!BN_GENCB_call(cb, 3, 0)) goto err;
-
-               /* step 6 */
-               counter=0;
-               /* "offset = 2" */
-
-               n=(bits-1)/160;
-
-               for (;;)
-                       {
-                       if ((counter != 0) && !BN_GENCB_call(cb, 0, counter))
-                               goto err;
-
-                       /* step 7 */
-                       BN_zero(W);
-                       /* now 'buf' contains "SEED + offset - 1" */
-                       for (k=0; k<=n; k++)
-                               {
-                               /* obtain "SEED + offset + k" by incrementing: */
-                               for (i = qsize-1; i >= 0; i--)
-                                       {
-                                       buf[i]++;
-                                       if (buf[i] != 0)
-                                               break;
-                                       }
-
-                               if (!EVP_Digest(buf, qsize, md ,NULL, evpmd,
-                                                                       NULL))
-                                       goto err;
-
-                               /* step 8 */
-                               if (!BN_bin2bn(md, qsize, r0))
-                                       goto err;
-                               if (!BN_lshift(r0,r0,(qsize << 3)*k)) goto err;
-                               if (!BN_add(W,W,r0)) goto err;
-                               }
-
-                       /* more of step 8 */
-                       if (!BN_mask_bits(W,bits-1)) goto err;
-                       if (!BN_copy(X,W)) goto err;
-                       if (!BN_add(X,X,test)) goto err;
-
-                       /* step 9 */
-                       if (!BN_lshift1(r0,q)) goto err;
-                       if (!BN_mod(c,X,r0,ctx)) goto err;
-                       if (!BN_sub(r0,c,BN_value_one())) goto err;
-                       if (!BN_sub(p,X,r0)) goto err;
-
-                       /* step 10 */
-                       if (BN_cmp(p,test) >= 0)
-                               {
-                               /* step 11 */
-                               r = BN_is_prime_fasttest_ex(p, DSS_prime_checks,
-                                               ctx, 1, cb);
-                               if (r > 0)
-                                               goto end; /* found it */
-                               if (r != 0)
-                                       goto err;
-                               }
-
-                       /* step 13 */
-                       counter++;
-                       /* "offset = offset + n + 1" */
-
-                       /* step 14 */
-                       if (counter >= 4096) break;
-                       }
-               }
-end:
-       if(!BN_GENCB_call(cb, 2, 1))
-               goto err;
-
-       /* We now need to generate g */
-       /* Set r0=(p-1)/q */
-       if (!BN_sub(test,p,BN_value_one())) goto err;
-       if (!BN_div(r0,NULL,test,q,ctx)) goto err;
-
-       if (!BN_set_word(test,h)) goto err;
-       if (!BN_MONT_CTX_set(mont,p,ctx)) goto err;
-
-       for (;;)
-               {
-               /* g=test^r0%p */
-               if (!BN_mod_exp_mont(g,test,r0,p,ctx,mont)) goto err;
-               if (!BN_is_one(g)) break;
-               if (!BN_add(test,test,BN_value_one())) goto err;
-               h++;
-               }
-
-       if(!BN_GENCB_call(cb, 3, 1))
-               goto err;
-
-       ok=1;
-err:
-       if (ok)
-               {
-               if(ret->p) BN_free(ret->p);
-               if(ret->q) BN_free(ret->q);
-               if(ret->g) BN_free(ret->g);
-               ret->p=BN_dup(p);
-               ret->q=BN_dup(q);
-               ret->g=BN_dup(g);
-               if (ret->p == NULL || ret->q == NULL || ret->g == NULL)
-                       {
-                       ok=0;
-                       goto err;
-                       }
-               if (counter_ret != NULL) *counter_ret=counter;
-               if (h_ret != NULL) *h_ret=h;
-               if (seed_out)
-                       memcpy(seed_out, seed, qsize);
-               }
-       if(ctx)
-               {
-               BN_CTX_end(ctx);
-               BN_CTX_free(ctx);
-               }
-       if (mont != NULL) BN_MONT_CTX_free(mont);
-       return ok;
-       }
-
-/* This is a parameter generation algorithm for the DSA2 algorithm as
+                         const EVP_MD *evpmd, const unsigned char *seed_in,
+                         size_t seed_len, unsigned char *seed_out,
+                         int *counter_ret, unsigned long *h_ret, BN_GENCB *cb)
+{
+    int ok = 0;
+    unsigned char seed[SHA256_DIGEST_LENGTH];
+    unsigned char md[SHA256_DIGEST_LENGTH];
+    unsigned char buf[SHA256_DIGEST_LENGTH], buf2[SHA256_DIGEST_LENGTH];
+    BIGNUM *r0, *W, *X, *c, *test;
+    BIGNUM *g = NULL, *q = NULL, *p = NULL;
+    BN_MONT_CTX *mont = NULL;
+    int i, k, n = 0, m = 0, qsize = qbits >> 3;
+    int counter = 0;
+    int r = 0;
+    BN_CTX *ctx = NULL;
+    unsigned int h = 2;
+
+    if (qsize != SHA_DIGEST_LENGTH && qsize != SHA224_DIGEST_LENGTH &&
+        qsize != SHA256_DIGEST_LENGTH)
+        /* invalid q size */
+        return 0;
+
+    if (evpmd == NULL)
+        /* use SHA1 as default */
+        evpmd = EVP_sha1();
+
+    if (bits < 512)
+        bits = 512;
+
+    bits = (bits + 63) / 64 * 64;
+
+    if (seed_in != NULL) {
+        if (seed_len < (size_t)qsize)
+            return 0;
+        if (seed_len > (size_t)qsize) {
+            /* Only consume as much seed as is expected. */
+            seed_len = qsize;
+        }
+        memcpy(seed, seed_in, seed_len);
+    }
+
+    if ((mont = BN_MONT_CTX_new()) == NULL)
+        goto err;
+
+    if ((ctx = BN_CTX_new()) == NULL)
+        goto err;
+
+    BN_CTX_start(ctx);
+
+    r0 = BN_CTX_get(ctx);
+    g = BN_CTX_get(ctx);
+    W = BN_CTX_get(ctx);
+    q = BN_CTX_get(ctx);
+    X = BN_CTX_get(ctx);
+    c = BN_CTX_get(ctx);
+    p = BN_CTX_get(ctx);
+    test = BN_CTX_get(ctx);
+
+    if (!BN_lshift(test, BN_value_one(), bits - 1))
+        goto err;
+
+    for (;;) {
+        for (;;) {              /* find q */
+            int use_random_seed = (seed_in == NULL);
+
+            /* step 1 */
+            if (!BN_GENCB_call(cb, 0, m++))
+                goto err;
+
+            if (use_random_seed) {
+                if (RAND_bytes(seed, qsize) <= 0)
+                    goto err;
+            } else {
+                /* If we come back through, use random seed next time. */
+                seed_in = NULL;
+            }
+            memcpy(buf, seed, qsize);
+            memcpy(buf2, seed, qsize);
+            /* precompute "SEED + 1" for step 7: */
+            for (i = qsize - 1; i >= 0; i--) {
+                buf[i]++;
+                if (buf[i] != 0)
+                    break;
+            }
+
+            /* step 2 */
+            if (!EVP_Digest(seed, qsize, md, NULL, evpmd, NULL))
+                goto err;
+            if (!EVP_Digest(buf, qsize, buf2, NULL, evpmd, NULL))
+                goto err;
+            for (i = 0; i < qsize; i++)
+                md[i] ^= buf2[i];
+
+            /* step 3 */
+            md[0] |= 0x80;
+            md[qsize - 1] |= 0x01;
+            if (!BN_bin2bn(md, qsize, q))
+                goto err;
+
+            /* step 4 */
+            r = BN_is_prime_fasttest_ex(q, DSS_prime_checks, ctx,
+                                        use_random_seed, cb);
+            if (r > 0)
+                break;
+            if (r != 0)
+                goto err;
+
+            /* do a callback call */
+            /* step 5 */
+        }
+
+        if (!BN_GENCB_call(cb, 2, 0))
+            goto err;
+        if (!BN_GENCB_call(cb, 3, 0))
+            goto err;
+
+        /* step 6 */
+        counter = 0;
+        /* "offset = 2" */
+
+        n = (bits - 1) / 160;
+
+        for (;;) {
+            if ((counter != 0) && !BN_GENCB_call(cb, 0, counter))
+                goto err;
+
+            /* step 7 */
+            BN_zero(W);
+            /* now 'buf' contains "SEED + offset - 1" */
+            for (k = 0; k <= n; k++) {
+                /*
+                 * obtain "SEED + offset + k" by incrementing:
+                 */
+                for (i = qsize - 1; i >= 0; i--) {
+                    buf[i]++;
+                    if (buf[i] != 0)
+                        break;
+                }
+
+                if (!EVP_Digest(buf, qsize, md, NULL, evpmd, NULL))
+                    goto err;
+
+                /* step 8 */
+                if (!BN_bin2bn(md, qsize, r0))
+                    goto err;
+                if (!BN_lshift(r0, r0, (qsize << 3) * k))
+                    goto err;
+                if (!BN_add(W, W, r0))
+                    goto err;
+            }
+
+            /* more of step 8 */
+            if (!BN_mask_bits(W, bits - 1))
+                goto err;
+            if (!BN_copy(X, W))
+                goto err;
+            if (!BN_add(X, X, test))
+                goto err;
+
+            /* step 9 */
+            if (!BN_lshift1(r0, q))
+                goto err;
+            if (!BN_mod(c, X, r0, ctx))
+                goto err;
+            if (!BN_sub(r0, c, BN_value_one()))
+                goto err;
+            if (!BN_sub(p, X, r0))
+                goto err;
+
+            /* step 10 */
+            if (BN_cmp(p, test) >= 0) {
+                /* step 11 */
+                r = BN_is_prime_fasttest_ex(p, DSS_prime_checks, ctx, 1, cb);
+                if (r > 0)
+                    goto end;   /* found it */
+                if (r != 0)
+                    goto err;
+            }
+
+            /* step 13 */
+            counter++;
+            /* "offset = offset + n + 1" */
+
+            /* step 14 */
+            if (counter >= 4096)
+                break;
+        }
+    }
+ end:
+    if (!BN_GENCB_call(cb, 2, 1))
+        goto err;
+
+    /* We now need to generate g */
+    /* Set r0=(p-1)/q */
+    if (!BN_sub(test, p, BN_value_one()))
+        goto err;
+    if (!BN_div(r0, NULL, test, q, ctx))
+        goto err;
+
+    if (!BN_set_word(test, h))
+        goto err;
+    if (!BN_MONT_CTX_set(mont, p, ctx))
+        goto err;
+
+    for (;;) {
+        /* g=test^r0%p */
+        if (!BN_mod_exp_mont(g, test, r0, p, ctx, mont))
+            goto err;
+        if (!BN_is_one(g))
+            break;
+        if (!BN_add(test, test, BN_value_one()))
+            goto err;
+        h++;
+    }
+
+    if (!BN_GENCB_call(cb, 3, 1))
+        goto err;
+
+    ok = 1;
+ err:
+    if (ok) {
+        BN_free(ret->p);
+        BN_free(ret->q);
+        BN_free(ret->g);
+        ret->p = BN_dup(p);
+        ret->q = BN_dup(q);
+        ret->g = BN_dup(g);
+        if (ret->p == NULL || ret->q == NULL || ret->g == NULL) {
+            ok = 0;
+            goto err;
+        }
+        if (counter_ret != NULL)
+            *counter_ret = counter;
+        if (h_ret != NULL)
+            *h_ret = h;
+        if (seed_out)
+            memcpy(seed_out, seed, qsize);
+    }
+    if (ctx)
+        BN_CTX_end(ctx);
+    BN_CTX_free(ctx);
+    BN_MONT_CTX_free(mont);
+    return ok;
+}
+
+/*
+ * This is a parameter generation algorithm for the DSA2 algorithm as
  * described in FIPS 186-3.
  */
 
 int dsa_builtin_paramgen2(DSA *ret, size_t L, size_t N,
-       const EVP_MD *evpmd, const unsigned char *seed_in, size_t seed_len,
-       int idx, unsigned char *seed_out,
-       int *counter_ret, unsigned long *h_ret, BN_GENCB *cb)
-       {
-       int ok=-1;
-       unsigned char *seed = NULL, *seed_tmp = NULL;
-       unsigned char md[EVP_MAX_MD_SIZE];
-       int mdsize;
-       BIGNUM *r0,*W,*X,*c,*test;
-       BIGNUM *g=NULL,*q=NULL,*p=NULL;
-       BN_MONT_CTX *mont=NULL;
-       int i, k, n=0, m=0, qsize = N >> 3;
-       int counter=0;
-       int r=0;
-       BN_CTX *ctx=NULL;
-       EVP_MD_CTX mctx;
-       unsigned int h=2;
-
-       EVP_MD_CTX_init(&mctx);
-
-       if (evpmd == NULL)
-               {
-               if (N == 160)
-                       evpmd = EVP_sha1();
-               else if (N == 224)
-                       evpmd = EVP_sha224();
-               else
-                       evpmd = EVP_sha256();
-               }
-
-       mdsize = M_EVP_MD_size(evpmd);
-       /* If unverificable g generation only don't need seed */
-       if (!ret->p || !ret->q || idx >= 0)
-               {
-               if (seed_len == 0)
-                       seed_len = mdsize;
-
-               seed = OPENSSL_malloc(seed_len);
-
-               if (seed_out)
-                       seed_tmp = seed_out;
-               else
-                       seed_tmp = OPENSSL_malloc(seed_len);
-
-               if (!seed || !seed_tmp)
-                       goto err;
-
-               if (seed_in)
-                       memcpy(seed, seed_in, seed_len);
-
-               }
-
-       if ((ctx=BN_CTX_new()) == NULL)
-               goto err;
-
-       if ((mont=BN_MONT_CTX_new()) == NULL)
-               goto err;
-
-       BN_CTX_start(ctx);
-       r0 = BN_CTX_get(ctx);
-       g = BN_CTX_get(ctx);
-       W = BN_CTX_get(ctx);
-       X = BN_CTX_get(ctx);
-       c = BN_CTX_get(ctx);
-       test = BN_CTX_get(ctx);
-
-       /* if p, q already supplied generate g only */
-       if (ret->p && ret->q)
-               {
-               p = ret->p;
-               q = ret->q;
-               if (idx >= 0)
-                       memcpy(seed_tmp, seed, seed_len);
-               goto g_only;
-               }
-       else
-               {
-               p = BN_CTX_get(ctx);
-               q = BN_CTX_get(ctx);
-               }
-
-       if (!BN_lshift(test,BN_value_one(),L-1))
-               goto err;
-       for (;;)
-               {
-               for (;;) /* find q */
-                       {
-                       unsigned char *pmd;
-                       /* step 1 */
-                       if(!BN_GENCB_call(cb, 0, m++))
-                               goto err;
-
-                       if (!seed_in)
-                               {
-                               if (RAND_pseudo_bytes(seed, seed_len) < 0)
-                                       goto err;
-                               }
-                       /* step 2 */
-                       if (!EVP_Digest(seed, seed_len, md, NULL, evpmd, NULL))
-                               goto err;
-                       /* Take least significant bits of md */
-                       if (mdsize > qsize)
-                               pmd = md + mdsize - qsize;
-                       else
-                               pmd = md;
-
-                       if (mdsize < qsize)
-                               memset(md + mdsize, 0, qsize - mdsize);
-
-                       /* step 3 */
-                       pmd[0] |= 0x80;
-                       pmd[qsize-1] |= 0x01;
-                       if (!BN_bin2bn(pmd, qsize, q))
-                               goto err;
-
-                       /* step 4 */
-                       r = BN_is_prime_fasttest_ex(q, DSS_prime_checks, ctx,
-                                       seed_in ? 1 : 0, cb);
-                       if (r > 0)
-                               break;
-                       if (r != 0)
-                               goto err;
-                       /* Provided seed didn't produce a prime: error */
-                       if (seed_in)
-                               {
-                               ok = 0;
-                               DSAerr(DSA_F_DSA_BUILTIN_PARAMGEN2, DSA_R_Q_NOT_PRIME);
-                               goto err;
-                               }
-
-                       /* do a callback call */
-                       /* step 5 */
-                       }
-               /* Copy seed to seed_out before we mess with it */
-               if (seed_out)
-                       memcpy(seed_out, seed, seed_len);
-
-               if(!BN_GENCB_call(cb, 2, 0)) goto err;
-               if(!BN_GENCB_call(cb, 3, 0)) goto err;
-
-               /* step 6 */
-               counter=0;
-               /* "offset = 1" */
-
-               n=(L-1)/(mdsize << 3);
-
-               for (;;)
-                       {
-                       if ((counter != 0) && !BN_GENCB_call(cb, 0, counter))
-                               goto err;
-
-                       /* step 7 */
-                       BN_zero(W);
-                       /* now 'buf' contains "SEED + offset - 1" */
-                       for (k=0; k<=n; k++)
-                               {
-                               /* obtain "SEED + offset + k" by incrementing: */
-                               for (i = seed_len-1; i >= 0; i--)
-                                       {
-                                       seed[i]++;
-                                       if (seed[i] != 0)
-                                               break;
-                                       }
-
-                               if (!EVP_Digest(seed, seed_len, md ,NULL, evpmd,
-                                                                       NULL))
-                                       goto err;
-
-                               /* step 8 */
-                               if (!BN_bin2bn(md, mdsize, r0))
-                                       goto err;
-                               if (!BN_lshift(r0,r0,(mdsize << 3)*k)) goto err;
-                               if (!BN_add(W,W,r0)) goto err;
-                               }
-
-                       /* more of step 8 */
-                       if (!BN_mask_bits(W,L-1)) goto err;
-                       if (!BN_copy(X,W)) goto err;
-                       if (!BN_add(X,X,test)) goto err;
-
-                       /* step 9 */
-                       if (!BN_lshift1(r0,q)) goto err;
-                       if (!BN_mod(c,X,r0,ctx)) goto err;
-                       if (!BN_sub(r0,c,BN_value_one())) goto err;
-                       if (!BN_sub(p,X,r0)) goto err;
-
-                       /* step 10 */
-                       if (BN_cmp(p,test) >= 0)
-                               {
-                               /* step 11 */
-                               r = BN_is_prime_fasttest_ex(p, DSS_prime_checks,
-                                               ctx, 1, cb);
-                               if (r > 0)
-                                               goto end; /* found it */
-                               if (r != 0)
-                                       goto err;
-                               }
-
-                       /* step 13 */
-                       counter++;
-                       /* "offset = offset + n + 1" */
-
-                       /* step 14 */
-                       if (counter >= (int)(4 * L)) break;
-                       }
-               if (seed_in)
-                       {
-                       ok = 0;
-                       DSAerr(DSA_F_DSA_BUILTIN_PARAMGEN2, DSA_R_INVALID_PARAMETERS);
-                       goto err;
-                       }
-               }
-end:
-       if(!BN_GENCB_call(cb, 2, 1))
-               goto err;
-
-       g_only:
-
-       /* We now need to generate g */
-       /* Set r0=(p-1)/q */
-       if (!BN_sub(test,p,BN_value_one())) goto err;
-       if (!BN_div(r0,NULL,test,q,ctx)) goto err;
-
-       if (idx < 0)
-               {
-               if (!BN_set_word(test,h))
-                       goto err;
-               }
-       else
-               h = 1;
-       if (!BN_MONT_CTX_set(mont,p,ctx)) goto err;
-
-       for (;;)
-               {
-               static const unsigned char ggen[4] = {0x67,0x67,0x65,0x6e};
-               if (idx >= 0)
-                       {
-                       md[0] = idx & 0xff;
-                       md[1] = (h >> 8) & 0xff;
-                       md[2] = h & 0xff;
-                       if (!EVP_DigestInit_ex(&mctx, evpmd, NULL))
-                               goto err;
-                       if (!EVP_DigestUpdate(&mctx, seed_tmp, seed_len))
-                               goto err;
-                       if (!EVP_DigestUpdate(&mctx, ggen, sizeof(ggen)))
-                               goto err;
-                       if (!EVP_DigestUpdate(&mctx, md, 3))
-                               goto err;
-                       if (!EVP_DigestFinal_ex(&mctx, md, NULL))
-                               goto err;
-                       if (!BN_bin2bn(md, mdsize, test))
-                               goto err;
-                       }
-               /* g=test^r0%p */
-               if (!BN_mod_exp_mont(g,test,r0,p,ctx,mont)) goto err;
-               if (!BN_is_one(g)) break;
-               if (idx < 0 && !BN_add(test,test,BN_value_one())) goto err;
-               h++;
-               if ( idx >= 0 && h > 0xffff)
-                       goto err;
-               }
-
-       if(!BN_GENCB_call(cb, 3, 1))
-               goto err;
-
-       ok=1;
-err:
-       if (ok == 1)
-               {
-               if (p != ret->p)
-                       {
-                       if(ret->p) BN_free(ret->p);
-                       ret->p=BN_dup(p);
-                       }
-               if (q != ret->q)
-                       {
-                       if(ret->q) BN_free(ret->q);
-                       ret->q=BN_dup(q);
-                       }
-               if(ret->g) BN_free(ret->g);
-               ret->g=BN_dup(g);
-               if (ret->p == NULL || ret->q == NULL || ret->g == NULL)
-                       {
-                       ok=-1;
-                       goto err;
-                       }
-               if (counter_ret != NULL) *counter_ret=counter;
-               if (h_ret != NULL) *h_ret=h;
-               }
-       if (seed)
-               OPENSSL_free(seed);
-       if (seed_out != seed_tmp)
-               OPENSSL_free(seed_tmp);
-       if(ctx)
-               {
-               BN_CTX_end(ctx);
-               BN_CTX_free(ctx);
-               }
-       if (mont != NULL) BN_MONT_CTX_free(mont);
-       EVP_MD_CTX_cleanup(&mctx);
-       return ok;
-       }
-
-int dsa_paramgen_check_g(DSA *dsa)
-       {
-       BN_CTX *ctx;
-       BIGNUM *tmp;
-       BN_MONT_CTX *mont = NULL;
-       int rv = -1;
-       ctx = BN_CTX_new();
-       if (!ctx)
-               return -1;
-       BN_CTX_start(ctx);
-       if (BN_cmp(dsa->g, BN_value_one()) <= 0)
-               return 0;
-       if (BN_cmp(dsa->g, dsa->p) >= 0)
-               return 0;
-       tmp = BN_CTX_get(ctx);
-       if (!tmp)
-               goto err;
-       if ((mont=BN_MONT_CTX_new()) == NULL)
-               goto err;
-       if (!BN_MONT_CTX_set(mont,dsa->p,ctx))
-               goto err;
-       /* Work out g^q mod p */
-       if (!BN_mod_exp_mont(tmp,dsa->g,dsa->q, dsa->p, ctx, mont))
-               goto err;
-       if (!BN_cmp(tmp, BN_value_one()))
-               rv = 1;
-       else
-               rv = 0;
-       err:
-       BN_CTX_end(ctx);
-       if (mont)
-               BN_MONT_CTX_free(mont);
-       BN_CTX_free(ctx);
-       return rv;
-
-       }
-
-#endif
+                          const EVP_MD *evpmd, const unsigned char *seed_in,
+                          size_t seed_len, int idx, unsigned char *seed_out,
+                          int *counter_ret, unsigned long *h_ret,
+                          BN_GENCB *cb)
+{
+    int ok = -1;
+    unsigned char *seed = NULL, *seed_tmp = NULL;
+    unsigned char md[EVP_MAX_MD_SIZE];
+    int mdsize;
+    BIGNUM *r0, *W, *X, *c, *test;
+    BIGNUM *g = NULL, *q = NULL, *p = NULL;
+    BN_MONT_CTX *mont = NULL;
+    int i, k, n = 0, m = 0, qsize = N >> 3;
+    int counter = 0;
+    int r = 0;
+    BN_CTX *ctx = NULL;
+    EVP_MD_CTX *mctx = EVP_MD_CTX_new();
+    unsigned int h = 2;
+
+    if (mctx == NULL)
+        goto err;
+
+    if (evpmd == NULL) {
+        if (N == 160)
+            evpmd = EVP_sha1();
+        else if (N == 224)
+            evpmd = EVP_sha224();
+        else
+            evpmd = EVP_sha256();
+    }
+
+    mdsize = EVP_MD_size(evpmd);
+    /* If unverifiable g generation only don't need seed */
+    if (!ret->p || !ret->q || idx >= 0) {
+        if (seed_len == 0)
+            seed_len = mdsize;
+
+        seed = OPENSSL_malloc(seed_len);
+
+        if (seed_out)
+            seed_tmp = seed_out;
+        else
+            seed_tmp = OPENSSL_malloc(seed_len);
+
+        if (seed == NULL || seed_tmp == NULL)
+            goto err;
+
+        if (seed_in)
+            memcpy(seed, seed_in, seed_len);
+
+    }
+
+    if ((ctx = BN_CTX_new()) == NULL)
+        goto err;
+
+    if ((mont = BN_MONT_CTX_new()) == NULL)
+        goto err;
+
+    BN_CTX_start(ctx);
+    r0 = BN_CTX_get(ctx);
+    g = BN_CTX_get(ctx);
+    W = BN_CTX_get(ctx);
+    X = BN_CTX_get(ctx);
+    c = BN_CTX_get(ctx);
+    test = BN_CTX_get(ctx);
+    if (test == NULL)
+        goto err;
+
+    /* if p, q already supplied generate g only */
+    if (ret->p && ret->q) {
+        p = ret->p;
+        q = ret->q;
+        if (idx >= 0)
+            memcpy(seed_tmp, seed, seed_len);
+        goto g_only;
+    } else {
+        p = BN_CTX_get(ctx);
+        q = BN_CTX_get(ctx);
+    }
+
+    if (!BN_lshift(test, BN_value_one(), L - 1))
+        goto err;
+    for (;;) {
+        for (;;) {              /* find q */
+            unsigned char *pmd;
+            /* step 1 */
+            if (!BN_GENCB_call(cb, 0, m++))
+                goto err;
+
+            if (!seed_in) {
+                if (RAND_bytes(seed, seed_len) <= 0)
+                    goto err;
+            }
+            /* step 2 */
+            if (!EVP_Digest(seed, seed_len, md, NULL, evpmd, NULL))
+                goto err;
+            /* Take least significant bits of md */
+            if (mdsize > qsize)
+                pmd = md + mdsize - qsize;
+            else
+                pmd = md;
+
+            if (mdsize < qsize)
+                memset(md + mdsize, 0, qsize - mdsize);
+
+            /* step 3 */
+            pmd[0] |= 0x80;
+            pmd[qsize - 1] |= 0x01;
+            if (!BN_bin2bn(pmd, qsize, q))
+                goto err;
+
+            /* step 4 */
+            r = BN_is_prime_fasttest_ex(q, DSS_prime_checks, ctx,
+                                        seed_in ? 1 : 0, cb);
+            if (r > 0)
+                break;
+            if (r != 0)
+                goto err;
+            /* Provided seed didn't produce a prime: error */
+            if (seed_in) {
+                ok = 0;
+                DSAerr(DSA_F_DSA_BUILTIN_PARAMGEN2, DSA_R_Q_NOT_PRIME);
+                goto err;
+            }
+
+            /* do a callback call */
+            /* step 5 */
+        }
+        /* Copy seed to seed_out before we mess with it */
+        if (seed_out)
+            memcpy(seed_out, seed, seed_len);
+
+        if (!BN_GENCB_call(cb, 2, 0))
+            goto err;
+        if (!BN_GENCB_call(cb, 3, 0))
+            goto err;
+
+        /* step 6 */
+        counter = 0;
+        /* "offset = 1" */
+
+        n = (L - 1) / (mdsize << 3);
+
+        for (;;) {
+            if ((counter != 0) && !BN_GENCB_call(cb, 0, counter))
+                goto err;
+
+            /* step 7 */
+            BN_zero(W);
+            /* now 'buf' contains "SEED + offset - 1" */
+            for (k = 0; k <= n; k++) {
+                /*
+                 * obtain "SEED + offset + k" by incrementing:
+                 */
+                for (i = seed_len - 1; i >= 0; i--) {
+                    seed[i]++;
+                    if (seed[i] != 0)
+                        break;
+                }
+
+                if (!EVP_Digest(seed, seed_len, md, NULL, evpmd, NULL))
+                    goto err;
+
+                /* step 8 */
+                if (!BN_bin2bn(md, mdsize, r0))
+                    goto err;
+                if (!BN_lshift(r0, r0, (mdsize << 3) * k))
+                    goto err;
+                if (!BN_add(W, W, r0))
+                    goto err;
+            }
+
+            /* more of step 8 */
+            if (!BN_mask_bits(W, L - 1))
+                goto err;
+            if (!BN_copy(X, W))
+                goto err;
+            if (!BN_add(X, X, test))
+                goto err;
+
+            /* step 9 */
+            if (!BN_lshift1(r0, q))
+                goto err;
+            if (!BN_mod(c, X, r0, ctx))
+                goto err;
+            if (!BN_sub(r0, c, BN_value_one()))
+                goto err;
+            if (!BN_sub(p, X, r0))
+                goto err;
+
+            /* step 10 */
+            if (BN_cmp(p, test) >= 0) {
+                /* step 11 */
+                r = BN_is_prime_fasttest_ex(p, DSS_prime_checks, ctx, 1, cb);
+                if (r > 0)
+                    goto end;   /* found it */
+                if (r != 0)
+                    goto err;
+            }
+
+            /* step 13 */
+            counter++;
+            /* "offset = offset + n + 1" */
+
+            /* step 14 */
+            if (counter >= (int)(4 * L))
+                break;
+        }
+        if (seed_in) {
+            ok = 0;
+            DSAerr(DSA_F_DSA_BUILTIN_PARAMGEN2, DSA_R_INVALID_PARAMETERS);
+            goto err;
+        }
+    }
+ end:
+    if (!BN_GENCB_call(cb, 2, 1))
+        goto err;
+
+ g_only:
+
+    /* We now need to generate g */
+    /* Set r0=(p-1)/q */
+    if (!BN_sub(test, p, BN_value_one()))
+        goto err;
+    if (!BN_div(r0, NULL, test, q, ctx))
+        goto err;
+
+    if (idx < 0) {
+        if (!BN_set_word(test, h))
+            goto err;
+    } else
+        h = 1;
+    if (!BN_MONT_CTX_set(mont, p, ctx))
+        goto err;
+
+    for (;;) {
+        static const unsigned char ggen[4] = { 0x67, 0x67, 0x65, 0x6e };
+        if (idx >= 0) {
+            md[0] = idx & 0xff;
+            md[1] = (h >> 8) & 0xff;
+            md[2] = h & 0xff;
+            if (!EVP_DigestInit_ex(mctx, evpmd, NULL))
+                goto err;
+            if (!EVP_DigestUpdate(mctx, seed_tmp, seed_len))
+                goto err;
+            if (!EVP_DigestUpdate(mctx, ggen, sizeof(ggen)))
+                goto err;
+            if (!EVP_DigestUpdate(mctx, md, 3))
+                goto err;
+            if (!EVP_DigestFinal_ex(mctx, md, NULL))
+                goto err;
+            if (!BN_bin2bn(md, mdsize, test))
+                goto err;
+        }
+        /* g=test^r0%p */
+        if (!BN_mod_exp_mont(g, test, r0, p, ctx, mont))
+            goto err;
+        if (!BN_is_one(g))
+            break;
+        if (idx < 0 && !BN_add(test, test, BN_value_one()))
+            goto err;
+        h++;
+        if (idx >= 0 && h > 0xffff)
+            goto err;
+    }
+
+    if (!BN_GENCB_call(cb, 3, 1))
+        goto err;
+
+    ok = 1;
+ err:
+    if (ok == 1) {
+        if (p != ret->p) {
+            BN_free(ret->p);
+            ret->p = BN_dup(p);
+        }
+        if (q != ret->q) {
+            BN_free(ret->q);
+            ret->q = BN_dup(q);
+        }
+        BN_free(ret->g);
+        ret->g = BN_dup(g);
+        if (ret->p == NULL || ret->q == NULL || ret->g == NULL) {
+            ok = -1;
+            goto err;
+        }
+        if (counter_ret != NULL)
+            *counter_ret = counter;
+        if (h_ret != NULL)
+            *h_ret = h;
+    }
+    OPENSSL_free(seed);
+    if (seed_out != seed_tmp)
+        OPENSSL_free(seed_tmp);
+    if (ctx)
+        BN_CTX_end(ctx);
+    BN_CTX_free(ctx);
+    BN_MONT_CTX_free(mont);
+    EVP_MD_CTX_free(mctx);
+    return ok;
+}