Shuffle functions into a more sensible order

BN_reciprocal() is only called by BN_div_recp() which in turn is only
called by BN_mod_mul_reciprocal(). So use this order and make the first
two static.

2 files changed, 39 insertions, 42 deletions

diff --git a/src/lib/libcrypto/bn/bn_local.h b/src/lib/libcrypto/bn/bn_local.h
index 58b5d54903..bfdff56b0e 100644
--- a/src/lib/libcrypto/bn/bn_local.h
+++ b/src/lib/libcrypto/bn/bn_local.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: bn_local.h,v 1.43 2024/04/16 13:07:14 jsing Exp $ */
+/* $OpenBSD: bn_local.h,v 1.44 2025/01/06 12:35:27 tb Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -280,8 +280,6 @@ int bn_rand_interval(BIGNUM *rnd, BN_ULONG lower_word, const BIGNUM *upper_exc);
 
 void    BN_init(BIGNUM *);
 
-int     BN_reciprocal(BIGNUM *r, const BIGNUM *m, int len, BN_CTX *ctx);
-
 void    BN_RECP_CTX_init(BN_RECP_CTX *recp);
 BN_RECP_CTX *BN_RECP_CTX_new(void);
 void    BN_RECP_CTX_free(BN_RECP_CTX *recp);
@@ -290,8 +288,6 @@ int	BN_mod_mul_reciprocal(BIGNUM *r, const BIGNUM *x, const BIGNUM *y,
     BN_RECP_CTX *recp, BN_CTX *ctx);
 int     BN_mod_exp_recp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
     const BIGNUM *m, BN_CTX *ctx);
-int     BN_div_recp(BIGNUM *dv, BIGNUM *rem, const BIGNUM *m,
-    BN_RECP_CTX *recp, BN_CTX *ctx);
 
 /* Explicitly const time / non-const time versions for internal use */
 int BN_mod_exp_ct(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
diff --git a/src/lib/libcrypto/bn/bn_recp.c b/src/lib/libcrypto/bn/bn_recp.c
index 35390e30d4..c567a5b017 100644
--- a/src/lib/libcrypto/bn/bn_recp.c
+++ b/src/lib/libcrypto/bn/bn_recp.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: bn_recp.c,v 1.19 2023/03/27 10:25:02 tb Exp $ */
+/* $OpenBSD: bn_recp.c,v 1.20 2025/01/06 12:35:27 tb Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -107,37 +107,35 @@ BN_RECP_CTX_set(BN_RECP_CTX *recp, const BIGNUM *d, BN_CTX *ctx)
         return (1);
 }
 
-int
-BN_mod_mul_reciprocal(BIGNUM *r, const BIGNUM *x, const BIGNUM *y,
-    BN_RECP_CTX *recp, BN_CTX *ctx)
+/* len is the expected size of the result
+ * We actually calculate with an extra word of precision, so
+ * we can do faster division if the remainder is not required.
+ */
+/* r := 2^len / m */
+static int
+BN_reciprocal(BIGNUM *r, const BIGNUM *m, int len, BN_CTX *ctx)
 {
-        int ret = 0;
-        BIGNUM *a;
-        const BIGNUM *ca;
+        int ret = -1;
+        BIGNUM *t;
 
         BN_CTX_start(ctx);
-        if ((a = BN_CTX_get(ctx)) == NULL)
+        if ((t = BN_CTX_get(ctx)) == NULL)
                 goto err;
-        if (y != NULL) {
-                if (x == y) {
-                        if (!BN_sqr(a, x, ctx))
-                                goto err;
-                } else {
-                        if (!BN_mul(a, x, y, ctx))
-                                goto err;
-                }
-                ca = a;
-        } else
-                ca = x; /* Just do the mod */
 
-        ret = BN_div_recp(NULL, r, ca, recp, ctx);
+        if (!BN_set_bit(t, len))
+                goto err;
+
+        if (!BN_div_ct(r, NULL, t,m, ctx))
+                goto err;
+
+        ret = len;
 
 err:
         BN_CTX_end(ctx);
         return (ret);
 }
 
-int
+static int
 BN_div_recp(BIGNUM *dv, BIGNUM *rem, const BIGNUM *m, BN_RECP_CTX *recp,
     BN_CTX *ctx)
 {
@@ -231,28 +229,31 @@ err:
         return (ret);
 }
 
-/* len is the expected size of the result
- * We actually calculate with an extra word of precision, so
- * we can do faster division if the remainder is not required.
- */
-/* r := 2^len / m */
+
 int
-BN_reciprocal(BIGNUM *r, const BIGNUM *m, int len, BN_CTX *ctx)
+BN_mod_mul_reciprocal(BIGNUM *r, const BIGNUM *x, const BIGNUM *y,
+    BN_RECP_CTX *recp, BN_CTX *ctx)
 {
-        int ret = -1;
-        BIGNUM *t;
+        int ret = 0;
+        BIGNUM *a;
+        const BIGNUM *ca;
 
         BN_CTX_start(ctx);
-        if ((t = BN_CTX_get(ctx)) == NULL)
-                goto err;
-
-        if (!BN_set_bit(t, len))
-                goto err;
-
-        if (!BN_div_ct(r, NULL, t,m, ctx))
+        if ((a = BN_CTX_get(ctx)) == NULL)
                 goto err;
+        if (y != NULL) {
+                if (x == y) {
+                        if (!BN_sqr(a, x, ctx))
+                                goto err;
+                } else {
+                        if (!BN_mul(a, x, y, ctx))
+                                goto err;
+                }
+                ca = a;
+        } else
+                ca = x; /* Just do the mod */
 
-        ret = len;
+        ret = BN_div_recp(NULL, r, ca, recp, ctx);
 
 err:
         BN_CTX_end(ctx);