diff --git a/Source/Core/Common/Crypto/bn.cpp b/Source/Core/Common/Crypto/bn.cpp
index 78ea444384..339b269d39 100644
--- a/Source/Core/Common/Crypto/bn.cpp
+++ b/Source/Core/Common/Crypto/bn.cpp
@@ -3,61 +3,43 @@
 // http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt
 
 #include <cstdio>
-#include <string.h>
+#include <cstring>
 
 #include "Common/CommonTypes.h"
 #include "Common/Crypto/bn.h"
 
-static void bn_zero(u8* d, u32 n)
+static void bn_zero(u8* d, int n)
 {
-  memset(d, 0, n);
+  std::memset(d, 0, n);
 }
 
-static void bn_copy(u8* d, const u8* a, u32 n)
+static void bn_copy(u8* d, const u8* a, int n)
 {
-  memcpy(d, a, n);
+  std::memcpy(d, a, n);
 }
 
-int bn_compare(const u8* a, const u8* b, u32 n)
+int bn_compare(const u8* a, const u8* b, int n)
 {
-  u32 i;
+  return std::memcmp(a, b, n);
+}
 
-  for (i = 0; i < n; i++)
+void bn_sub_modulus(u8* a, const u8* N, int n)
+{
+  u8 c = 0;
+  for (int i = n - 1; i >= 0; --i)
   {
-    if (a[i] < b[i])
-      return -1;
-    if (a[i] > b[i])
-      return 1;
-  }
-
-  return 0;
-}
-
-void bn_sub_modulus(u8* a, const u8* N, u32 n)
-{
-  u32 i;
-  u32 dig;
-  u8 c;
-
-  c = 0;
-  for (i = n - 1; i < n; i--)
-  {
-    dig = N[i] + c;
+    u32 dig = N[i] + c;
     c = (a[i] < dig);
     a[i] -= dig;
   }
 }
 
-void bn_add(u8* d, const u8* a, const u8* b, const u8* N, u32 n)
+void bn_add(u8* d, const u8* a, const u8* b, const u8* N, int n)
 {
-  u32 i;
-  u32 dig;
-  u8 c;
-
-  c = 0;
-  for (i = n - 1; i < n; i--)
+  u8 c = 0;
+  for (int i = n - 1; i >= 0; --i)
   {
-    dig = a[i] + b[i] + c;
+    u32 dig = a[i] + b[i] + c;
     c = (dig >= 0x100);
     d[i] = dig;
   }
@@ -69,32 +51,30 @@ void bn_add(u8* d, const u8* a, const u8* b, const u8* N, u32 n)
     bn_sub_modulus(d, N, n);
 }
 
-void bn_mul(u8* d, const u8* a, const u8* b, const u8* N, u32 n)
+void bn_mul(u8* d, const u8* a, const u8* b, const u8* N, int n)
 {
-  u32 i;
-  u8 mask;
-
   bn_zero(d, n);
 
-  for (i = 0; i < n; i++)
-    for (mask = 0x80; mask != 0; mask >>= 1)
+  for (int i = 0; i < n; i++)
+  {
+    for (u8 mask = 0x80; mask != 0; mask >>= 1)
     {
       bn_add(d, d, d, N, n);
       if ((a[i] & mask) != 0)
         bn_add(d, d, b, N, n);
     }
+  }
 }
 
-void bn_exp(u8* d, const u8* a, const u8* N, u32 n, const u8* e, u32 en)
+void bn_exp(u8* d, const u8* a, const u8* N, int n, const u8* e, int en)
 {
   u8 t[512];
-  u32 i;
-  u8 mask;
 
   bn_zero(d, n);
   d[n - 1] = 1;
-  for (i = 0; i < en; i++)
-    for (mask = 0x80; mask != 0; mask >>= 1)
+  for (int i = 0; i < en; i++)
+  {
+    for (u8 mask = 0x80; mask != 0; mask >>= 1)
     {
       bn_mul(t, d, d, N, n);
       if ((e[i] & mask) != 0)
@@ -102,10 +82,11 @@ void bn_exp(u8* d, const u8* a, const u8* N, u32 n, const u8* e, u32 en)
       else
         bn_copy(d, t, n);
     }
+  }
 }
 
 // only for prime N -- stupid but lazy, see if I care
-void bn_inv(u8* d, const u8* a, const u8* N, u32 n)
+void bn_inv(u8* d, const u8* a, const u8* N, int n)
 {
   u8 t[512], s[512];
 
diff --git a/Source/Core/Common/Crypto/bn.h b/Source/Core/Common/Crypto/bn.h
index 5c0c85b157..7ab2ab3fb1 100644
--- a/Source/Core/Common/Crypto/bn.h
+++ b/Source/Core/Common/Crypto/bn.h
@@ -8,9 +8,9 @@
 
 // bignum arithmetic
 
-int bn_compare(const u8* a, const u8* b, u32 n);
-void bn_sub_modulus(u8* a, const u8* N, u32 n);
-void bn_add(u8* d, const u8* a, const u8* b, const u8* N, u32 n);
-void bn_mul(u8* d, const u8* a, const u8* b, const u8* N, u32 n);
-void bn_inv(u8* d, const u8* a, const u8* N, u32 n);  // only for prime N
-void bn_exp(u8* d, const u8* a, const u8* N, u32 n, const u8* e, u32 en);
+int bn_compare(const u8* a, const u8* b, int n);
+void bn_sub_modulus(u8* a, const u8* N, int n);
+void bn_add(u8* d, const u8* a, const u8* b, const u8* N, int n);
+void bn_mul(u8* d, const u8* a, const u8* b, const u8* N, int n);
+void bn_inv(u8* d, const u8* a, const u8* N, int n);  // only for prime N
+void bn_exp(u8* d, const u8* a, const u8* N, int n, const u8* e, int en);