Update aes.h

aes.h

@@ -3,7 +3,38 @@
 
 #include <stdint.h>
 
+
+// #define the macros below to 1/0 to enable/disable the mode of operation.
+//
+// CBC enables AES128 encryption in CBC-mode of operation and handles 0-padding.
+// ECB enables the basic ECB 16-byte block algorithm. Both can be enabled simultaneously.
+
+// The #ifndef-guard allows it to be configured before #include'ing or at compile time.
+#ifndef CBC
+  #define CBC 1
+#endif
+
+#ifndef ECB
+  #define ECB 1
+#endif
+
+
+
+#if defined(ECB) && ECB
+
 void AES128_ECB_encrypt(uint8_t* input, const uint8_t* key, uint8_t *output);
 void AES128_ECB_decrypt(uint8_t* input, const uint8_t* key, uint8_t *output);
 
+#endif // #if defined(ECB) && ECB
+
+
+#if defined(CBC) && CBC
+
+void AES128_CBC_encrypt_buffer(uint8_t* output, uint8_t* input, uint32_t length, const uint8_t* key, const uint8_t* iv);
+void AES128_CBC_decrypt_buffer(uint8_t* output, uint8_t* input, uint32_t length, const uint8_t* key, const uint8_t* iv);
+
+#endif // #if defined(CBC) && CBC
+
+
+
 #endif //_AES_H_