added support for aes256_enc_single and aes256_dec_single

Author: klimacampimrheinland

AESLib.c

@@ -47,6 +47,15 @@ void aes128_enc_single(const uint8_t* key, void* data){
 	aes128_enc(data, &ctx);
 }
 
+// encrypt single 128bit block. data is assumed to be 16 uint8_t's
+// key and iv are assumed to be both 128bit thus 16 uint8_t's
+void aes256_enc_single(const uint16_t* key, void* data){
+	aes256_ctx_t ctx;
+	aes256_init(key, &ctx);
+	aes256_enc(data, &ctx);
+}
+
+
 // prepare an encrypted to use for encrypting multiple blocks lateron.
 // key and iv are assumed to be both 128bit thus 16 uint8_t's
 aes_context aes128_cbc_enc_start(const uint8_t* key, const void* iv){
@@ -106,6 +115,15 @@ void aes128_dec_single(const uint8_t* key, void* data){
 	aes128_dec(data, &ctx);
 }
 
+// decrypt single 128bit block. data is assumed to be 16 uint8_t's
+// key and iv are assumed to be both 128bit thus 16 uint8_t's
+void aes256_dec_single(const uint16_t* key, void* data){
+	aes256_ctx_t ctx;
+	aes256_init(key, &ctx);
+	aes256_dec(data, &ctx);
+}
+
+
 // prepare an decrypted to use for decrypting multiple blocks lateron.
 // key and iv are assumed to be both 128bit thus 16 uint8_t's
 aes_context aes128_cbc_dec_start(const uint8_t* key, const void* iv){

AESLib.h

@@ -29,6 +29,8 @@ void aes128_cbc_enc(const uint8_t* key, const uint8_t* iv, void* data, const uin
 // key and iv are assumed to be both 128bit thus 16 uint8_t's
 void aes128_enc_single(const uint8_t* key, void* data);
 
+void aes256_enc_single(const uint16_t* key, void* data);
+
 typedef void* aes_context;
 
 // prepare an encrypted to use for encrypting multiple blocks lateron.
@@ -50,6 +52,8 @@ void aes128_cbc_dec(const uint8_t* key, const uint8_t* iv, void* data, const uin
 // key and iv are assumed to be both 128bit thus 16 uint8_t's
 void aes128_dec_single(const uint8_t* key, void* data);
 
+void aes256_dec_single(const uint16_t* key, void* data);
+
 // prepare an decrypter to use for decrypting multiple blocks lateron.
 // key and iv are assumed to be both 128bit thus 16 uint8_t's
 aes_context aes128_cbc_dec_start(const uint8_t* key, const void* iv);

README.md

@@ -52,3 +52,17 @@ aes128_dec_single(key, data);
 Serial.print("decrypted:");
 Serial.println(data);
 ```
+
+Usage example for AES256:
+	
+```c
+Serial.begin(57600);
+uint8_t key[] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
+char data[] = "0123456789012345"; //16 chars == 16 bytes
+aes256_enc_single(key, data);
+Serial.print("encrypted:");
+Serial.println(data);
+aes256_dec_single(key, data);
+Serial.print("decrypted:");
+Serial.println(data);
+```