@@ -128,8 +128,10 @@ public:

     }

 private:

+    using reverse_map = std::unordered_map <char, unsigned char>;

+    using character_type = std::string::value_type;

-    std::unordered_map <char, unsigned char> construct_lookup_table() const

+    reverse_map construct_lookup_table() const

     {

         std::unordered_map<char, unsigned char> lookup_table;

@@ -188,6 +190,16 @@ private:

     }

+    uint8_t get_next_input(reverse_map &lookup_table, std::string &input, std::string::size_type idx) const {

+        character_type character = input[idx];

+

+        if (character != '=' && lookup_table.find(character) == lookup_table.end()) {

+            throw invalid_data_exception ();

+        }

+

+        return lookup_table[input[idx]];

+    }

+

 public:

     std::vector<uint8_t> decode (std::string input) const override

@@ -200,12 +212,10 @@ public:

         unsigned long long bits_written = 0;

         for (std::string::size_type idx = 0; idx < input.size(); idx++) {

-            // TODO: fail on invalid input

-            uint8_t val = lookup_table[input[idx]];

-

             uint8_t start_bit = bits_written % 8;

             std::vector<unsigned char>::size_type current_byte = bits_written/8;

+            uint8_t val = get_next_input(lookup_table, input, idx);

             set_vector_at_bit (result, val, current_byte, start_bit, 5);

             bits_written += 5;

@@ -221,4 +231,3 @@ template class std::vector<unsigned char>;

 base32::base32 ():

     delegate_ (std::make_shared<base32_impl> ())

 {}

-

@@ -16,6 +16,10 @@

 #include <vector>

 #include <string>

+class invalid_data_exception : public std::exception

+{

+};

+

 class base32_ifc

 {

 public:

@@ -44,4 +48,3 @@ public:

 };

 #endif

-

@@ -64,14 +64,24 @@ int decode_validates_input()

     // The token for key 76I6WTYEUTNCJUREMGKVM45PMA and time '2017/01/01 00:00:00' is 258675

     base32 codec = base32();

+    int num_exceptions = 0;

     try {

-        codec.decode ("\x00");

-        codec.decode ("\x00\x00\x00\x00\x00\x00\x00\x00\x00");

+        codec.decode ("A");

+        codec.decode ("AAAAAAAAA");

         fail ("invalid length should result in an exception");

     } catch (std::exception e) {

-        succeed();

+        num_exceptions++;

     }

+    try {

+        codec.decode ("--------");

+        fail ("invalid input characters should result in an exception");

+    } catch (invalid_data_exception) {

+        num_exceptions++;

+    }

+

+    check(num_exceptions == 2, "base32.decode should validate input data");

+

     succeed();

 }

@@ -107,4 +117,3 @@ int main (int argc, char *argv[])

 {

     return !run_tests();

 }

-

@@ -123,7 +123,7 @@ int installs_token()

 {

     //given

     std::string user_name ("user");

-    std::string key ("thekeyis");

+    std::string key ("THEKEYIS");

     std::string token ("thetoken");

     auto  test_tokens = std::make_shared<mock_tokens> (key);

     tokens tokens{test_tokens};

@@ -236,4 +236,3 @@ int main (int argc, char *argv[])

 {

     return !run_tests();

 }

-