Revert "destatic fe25519_pow22523()"

This reverts commit 3998cd7228.

src/libsodium/crypto_core/curve25519/core_curve25519.c

@@ -66,6 +66,61 @@ has_small_order(const unsigned char s[32])
     return (int) ((k >> 8) & 1);
 }
 
+static void
+fe25519_pow22523(fe25519 out, const fe25519 z)
+{
+    fe25519 t0;
+    fe25519 t1;
+    fe25519 t2;
+    int     i;
+
+    fe25519_sq(t0, z);
+    fe25519_sq(t1, t0);
+    fe25519_sq(t1, t1);
+    fe25519_mul(t1, z, t1);
+    fe25519_mul(t0, t0, t1);
+    fe25519_sq(t0, t0);
+    fe25519_mul(t0, t1, t0);
+    fe25519_sq(t1, t0);
+    for (i = 1; i < 5; ++i) {
+        fe25519_sq(t1, t1);
+    }
+    fe25519_mul(t0, t1, t0);
+    fe25519_sq(t1, t0);
+    for (i = 1; i < 10; ++i) {
+        fe25519_sq(t1, t1);
+    }
+    fe25519_mul(t1, t1, t0);
+    fe25519_sq(t2, t1);
+    for (i = 1; i < 20; ++i) {
+        fe25519_sq(t2, t2);
+    }
+    fe25519_mul(t1, t2, t1);
+    fe25519_sq(t1, t1);
+    for (i = 1; i < 10; ++i) {
+        fe25519_sq(t1, t1);
+    }
+    fe25519_mul(t0, t1, t0);
+    fe25519_sq(t1, t0);
+    for (i = 1; i < 50; ++i) {
+        fe25519_sq(t1, t1);
+    }
+    fe25519_mul(t1, t1, t0);
+    fe25519_sq(t2, t1);
+    for (i = 1; i < 100; ++i) {
+        fe25519_sq(t2, t2);
+    }
+    fe25519_mul(t1, t2, t1);
+    fe25519_sq(t1, t1);
+    for (i = 1; i < 50; ++i) {
+        fe25519_sq(t1, t1);
+    }
+    fe25519_mul(t0, t1, t0);
+    fe25519_sq(t0, t0);
+    fe25519_sq(t0, t0);
+    fe25519_mul(out, t0, z);
+}
+
 static int
 is_on_main_subgroup(const fe25519 x1)
 {

src/libsodium/crypto_core/ed25519/ref10/ed25519_ref10.c

@@ -108,7 +108,7 @@ fe25519_invert(fe25519 out, const fe25519 z)
     fe25519_mul(out, t1, t0);
 }
 
-void
+static void
 fe25519_pow22523(fe25519 out, const fe25519 z)
 {
     fe25519 t0;

src/libsodium/include/sodium/private/ed25519_ref10.h

@@ -17,7 +17,6 @@ typedef int32_t fe25519[10];
 
 void fe25519_invert(fe25519 out, const fe25519 z);
 void fe25519_frombytes(fe25519 h, const unsigned char *s);
-void fe25519_pow22523(fe25519 out, const fe25519 z);
 void fe25519_tobytes(unsigned char *s, const fe25519 h);
 
 #ifdef HAVE_TI_MODE