Merge pull request #54 from OmniTroid/master

Restructuring +  better cross-platform support

1 files changed, 63 insertions, 0 deletions

diff --git a/src/encryption_functions.cpp b/src/encryption_functions.cpp
new file mode 100644
index 00000000..ffbe0cdb
--- /dev/null
+++ b/src/encryption_functions.cpp
@@ -0,0 +1,63 @@
+#include "encryption_functions.h"
+
+#include "hex_functions.h"
+
+QString fanta_encrypt(QString temp_input, unsigned int p_key)
+{
+  //using standard stdlib types is actually easier here because of implicit char<->int conversion
+  //which in turn makes encryption arithmetic easier
+
+  unsigned int key = p_key;
+  unsigned int C1 = 53761;
+  unsigned int C2 = 32618;
+
+  QVector<uint_fast8_t> temp_result;
+  std::string input = temp_input.toUtf8().constData();
+
+  for (unsigned int pos = 0 ; pos < input.size() ; ++pos)
+  {
+    uint_fast8_t output = input.at(pos) ^ (key >> 8) % 256;
+    temp_result.append(output);
+    key = (temp_result.at(pos) + key) * C1 + C2;
+  }
+
+  std::string result = "";
+
+  for (uint_fast8_t i_int : temp_result)
+  {
+    result += omni::int_to_hex(i_int);
+  }
+
+  QString final_result = QString::fromStdString(result);
+
+  return final_result;
+}
+
+QString fanta_decrypt(QString temp_input, unsigned int key)
+{
+  std::string input = temp_input.toUtf8().constData();
+
+  QVector<unsigned int> unhexed_vector;
+
+  for(unsigned int i=0; i< input.length(); i+=2)
+  {
+    std::string byte = input.substr(i,2);
+    unsigned int hex_int = strtoul(byte.c_str(), nullptr, 16);
+    unhexed_vector.append(hex_int);
+  }
+
+  unsigned int C1 = 53761;
+  unsigned int C2 = 32618;
+
+  std::string result = "";
+
+  for (int pos = 0 ; pos < unhexed_vector.size() ; ++pos)
+  {
+    unsigned char output = unhexed_vector.at(pos) ^ (key >> 8) % 256;
+    result += output;
+    key = (unhexed_vector.at(pos) + key) * C1 + C2;
+  }
+
+  return QString::fromStdString(result);
+
+}