From 8adc867a2e0d0a7706681d343de29d6e04fd93f1 Mon Sep 17 00:00:00 2001
From: hashlag <hashlag@hashlag.local>
Date: Thu, 13 Aug 2026 01:17:54 +0300
Subject: [PATCH] PadderIso7816: Do not allow to pad empty ranges.

---
 Chaos/Padding/PadderIso7816.hpp           |  5 ++++
 ChaosTests/Padding/PadderIso7816Tests.cpp | 33 +++++++++++------------
 2 files changed, 21 insertions(+), 17 deletions(-)

diff --git a/Chaos/Padding/PadderIso7816.hpp b/Chaos/Padding/PadderIso7816.hpp
index 4acd000..547f6e7 100644
--- a/Chaos/Padding/PadderIso7816.hpp
+++ b/Chaos/Padding/PadderIso7816.hpp
@@ -7,6 +7,7 @@
 
 #include "Padding/Padder.hpp"
 #include "Service/Branchless.hpp"
+#include "Service/ChaosException.hpp"
 
 namespace Chaos::Padding
 {
@@ -28,6 +29,10 @@ public:
                 *it = 0;
             }
         }
+        else
+        {
+            throw Service::ChaosException("PadderIso7816::Pad(): invalid range");
+        }
     }
 
     struct ComputeUnpadResult
diff --git a/ChaosTests/Padding/PadderIso7816Tests.cpp b/ChaosTests/Padding/PadderIso7816Tests.cpp
index 233ac6c..c9c0a17 100644
--- a/ChaosTests/Padding/PadderIso7816Tests.cpp
+++ b/ChaosTests/Padding/PadderIso7816Tests.cpp
@@ -1,5 +1,6 @@
 #include <algorithm>
 #include <gtest/gtest.h>
+#include "TestHelpers/AssertThrowEx.hpp"
 
 #include <array>
 #include <cstdint>
@@ -8,6 +9,7 @@
 
 #include "Padding/PadderIso7816.hpp"
 #include "Padding/Padder.hpp"
+#include "Service/ChaosException.hpp"
 
 using namespace Chaos::Padding;
 
@@ -45,7 +47,7 @@ TEST(PadIso7816Tests, 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, 0xff);
 
@@ -58,6 +60,19 @@ TEST(PadIso7816Tests, PadTest)
     }
 }
 
+TEST(PadIso7816Tests, PadInvalidRangeTest)
+{
+    {
+        std::array<uint8_t, 3> out = {};
+
+        ASSERT_THROW_EX(PadderIso7816::Pad(out.begin(), out.begin()),
+                        Chaos::Service::ChaosException,
+                        {
+                            ASSERT_EQ("PadderIso7816::Pad(): invalid range", ex.GetMessage());
+                        });
+    }
+}
+
 TEST(PadIso7816Tests, PadOutIteratorUsageTest)
 {
     {
@@ -92,22 +107,6 @@ TEST(PadIso7816Tests, PadOutIteratorUsageTest)
         PadderIso7816::Pad(fact.begin() + 3, fact.end() - 3);
         ASSERT_EQ(expected, fact);
     }
-
-    {
-        std::array<uint8_t, 10> fact =
-        {
-            0xbb, 0xbb, 0xbb, 0xbb, 0xbb,
-            0xbb, 0xbb, 0xbb, 0xbb, 0xbb
-        };
-        std::array<uint8_t, 10> expected =
-        {
-            0xbb, 0xbb, 0xbb, 0xbb, 0xbb,
-            0xbb, 0xbb, 0xbb, 0xbb, 0xbb
-        };
-
-        PadderIso7816::Pad(fact.begin() + 5, fact.begin() + 5);
-        ASSERT_EQ(expected, fact);
-    }
 }
 
 template<typename Impl, typename OutputIt>