Next pass of bn_prime.c cleanup

Garbage collect a few pointless variables and remove a loop that wasn't
really a loop. Simplify BN_CTX handling and drop some stupid comments.

ok jsing miod

diff --git a/lib/libcrypto/bn/bn_prime.c b/lib/libcrypto/bn/bn_prime.c
index ea0733b..c3cf5b8 100644 (file)
--- a/lib/libcrypto/bn/bn_prime.c
+++ b/lib/libcrypto/bn/bn_prime.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: bn_prime.c,v 1.23 2022/11/09 02:01:13 tb Exp $ */
+/* $OpenBSD: bn_prime.c,v 1.24 2022/11/09 11:31:51 tb Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -116,8 +116,6 @@
 
 #include "bn_lcl.h"
 
-#define LIBRESSL_HAS_BPSW
-
 /* NB: these functions have been "upgraded", the deprecated versions (which are
  * compatibility wrappers using these functions) are in bn_depr.c.
  * - Geoff
@@ -164,9 +162,9 @@ BN_generate_prime_ex(BIGNUM *ret, int bits, int safe, const BIGNUM *add,
 {
        BIGNUM *t;
        int found = 0;
-       int i, j, c1 = 0;
+       int loops = 0;
+       int j;
        BN_CTX *ctx;
-       int checks = 1;
 
        if (bits < 2 || (bits == 2 && safe)) {
                /*
@@ -177,18 +175,13 @@ BN_generate_prime_ex(BIGNUM *ret, int bits, int safe, const BIGNUM *add,
                return 0;
        }
 
-       ctx = BN_CTX_new();
-       if (ctx == NULL)
+       if ((ctx = BN_CTX_new()) == NULL)
                goto err;
        BN_CTX_start(ctx);
        if ((t = BN_CTX_get(ctx)) == NULL)
                goto err;
 
-#ifndef LIBRESSL_HAS_BPSW
-       checks = BN_prime_checks_for_size(bits);
-#endif
-
-loop:
+ loop:
        /* make a random number and set the top and bottom bits */
        if (add == NULL) {
                if (!probable_prime(ret, bits))
@@ -202,16 +195,15 @@ loop:
                                goto err;
                }
        }
-       /* if (BN_mod_word(ret,(BN_ULONG)3) == 1) goto loop; */
-       if (!BN_GENCB_call(cb, 0, c1++))
-               /* aborted */
+
+       if (!BN_GENCB_call(cb, 0, loops++))
                goto err;
 
        if (!safe) {
-               i = BN_is_prime_fasttest_ex(ret, checks, ctx, 0, cb);
-               if (i == -1)
+               j = BN_is_prime_fasttest_ex(ret, 1, ctx, 0, cb);
+               if (j == -1)
                        goto err;
-               if (i == 0)
+               if (j == 0)
                        goto loop;
        } else {
                /* for "safe prime" generation,
@@ -221,33 +213,31 @@ loop:
                if (!BN_rshift1(t, ret))
                        goto err;
 
-               for (i = 0; i < checks; i++) {
-                       j = BN_is_prime_fasttest_ex(ret, 1, ctx, 0, cb);
-                       if (j == -1)
-                               goto err;
-                       if (j == 0)
-                               goto loop;
+               j = BN_is_prime_fasttest_ex(ret, 1, ctx, 0, cb);
+               if (j == -1)
+                       goto err;
+               if (j == 0)
+                       goto loop;
 
-                       j = BN_is_prime_fasttest_ex(t, 1, ctx, 0, cb);
-                       if (j == -1)
-                               goto err;
-                       if (j == 0)
-                               goto loop;
+               j = BN_is_prime_fasttest_ex(t, 1, ctx, 0, cb);
+               if (j == -1)
+                       goto err;
+               if (j == 0)
+                       goto loop;
 
-                       if (!BN_GENCB_call(cb, 2, c1 - 1))
-                               goto err;
-                       /* We have a safe prime test pass */
-               }
+               if (!BN_GENCB_call(cb, 2, loops - 1))
+                       goto err;
+
+               /* We have a safe prime test pass */
        }
-       /* we have a prime :-) */
+
        found = 1;
 
-err:
-       if (ctx != NULL) {
-               BN_CTX_end(ctx);
-               BN_CTX_free(ctx);
-       }
+ err:
+       BN_CTX_end(ctx);
+       BN_CTX_free(ctx);
        bn_check_top(ret);
+
        return found;
 }