PadderPkcs7: Do not allow to pad empty ranges.

Chaos/Padding/PadderPkcs7.hpp

@@ -21,8 +21,7 @@ public:
     {
         auto dist = std::distance(begin, end);
 
-        // TODO: dist > 0
-        if (dist >= 0 && dist <= std::numeric_limits<uint8_t>::max())
+        if (dist > 0 && dist <= std::numeric_limits<uint8_t>::max())
         {
             for (OutputIt it = begin; it != end; ++it)
             {

ChaosTests/Padding/PadderPkcs7Tests.cpp

@@ -45,7 +45,7 @@ TEST(PadPkcs7Tests, PadTest)
         ASSERT_EQ(expected, fact);
     }
 
-    for (int i = 0; i < 256; ++i)
+    for (int i = 1; i < 256; ++i)
     {
         std::vector<uint8_t> fact(i, 0x00);
 
@@ -85,6 +85,16 @@ TEST(PadPkcs7Tests, PadInvalidRangeTest)
                             ASSERT_EQ("PadderPkcs7::Pad(): invalid range", ex.GetMessage());
                         });
     }
+
+    {
+        std::array<uint8_t, 0> out = {};
+
+        ASSERT_THROW_EX(PadderPkcs7::Pad(out.end(), out.begin()),
+                        Chaos::Service::ChaosException,
+                        {
+                            ASSERT_EQ("PadderPkcs7::Pad(): invalid range", ex.GetMessage());
+                        });
+    }
 }
 
 TEST(PadPkcs7Tests, PadOutIteratorUsageTest)
@@ -127,10 +137,10 @@ TEST(PadPkcs7Tests, PadOutIteratorUsageTest)
         std::array<uint8_t, 10> expected =
         {
             0xbb, 0xbb, 0xbb, 0xbb, 0xbb,
-            0xbb, 0xbb, 0xbb, 0xbb, 0xbb
+            0x01, 0xbb, 0xbb, 0xbb, 0xbb
         };
 
-        PadderPkcs7::Pad(fact.begin() + 5, fact.begin() + 5);
+        PadderPkcs7::Pad(fact.begin() + 5, fact.begin() + 6);
         ASSERT_EQ(expected, fact);
     }
 }