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diff --git a/src/tiny-AES-c/aes.h b/src/tiny-AES-c/aes.h
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+#ifndef _AES_H_
+#define _AES_H_
+
+#include <stdint.h>
+
+// #define the macros below to 1/0 to enable/disable the mode of operation.
+//
+// CBC enables AES encryption in CBC-mode of operation.
+// CTR enables encryption in counter-mode.
+// ECB enables the basic ECB 16-byte block algorithm. All 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
+
+#ifndef CTR
+ #define CTR 1
+#endif
+
+
+#define AES128 1
+//#define AES192 1
+//#define AES256 1
+
+#define AES_BLOCKLEN 16 //Block length in bytes AES is 128b block only
+
+#if defined(AES256) && (AES256 == 1)
+ #define AES_KEYLEN 32
+ #define AES_keyExpSize 240
+#elif defined(AES192) && (AES192 == 1)
+ #define AES_KEYLEN 24
+ #define AES_keyExpSize 208
+#else
+ #define AES_KEYLEN 16 // Key length in bytes
+ #define AES_keyExpSize 176
+#endif
+
+struct AES_ctx
+{
+ uint8_t RoundKey[AES_keyExpSize];
+#if (defined(CBC) && (CBC == 1)) || (defined(CTR) && (CTR == 1))
+ uint8_t Iv[AES_BLOCKLEN];
+#endif
+};
+
+void AES_init_ctx(struct AES_ctx* ctx, const uint8_t* key);
+#if (defined(CBC) && (CBC == 1)) || (defined(CTR) && (CTR == 1))
+void AES_init_ctx_iv(struct AES_ctx* ctx, const uint8_t* key, const uint8_t* iv);
+void AES_ctx_set_iv(struct AES_ctx* ctx, const uint8_t* iv);
+#endif
+
+#if defined(ECB) && (ECB == 1)
+// buffer size is exactly AES_BLOCKLEN bytes;
+// you need only AES_init_ctx as IV is not used in ECB
+// NB: ECB is considered insecure for most uses
+void AES_ECB_encrypt(const struct AES_ctx* ctx, uint8_t* buf);
+void AES_ECB_decrypt(const struct AES_ctx* ctx, uint8_t* buf);
+
+#endif // #if defined(ECB) && (ECB == !)
+
+
+#if defined(CBC) && (CBC == 1)
+// buffer size MUST be mutile of AES_BLOCKLEN;
+// Suggest https://en.wikipedia.org/wiki/Padding_(cryptography)#PKCS7 for padding scheme
+// NOTES: you need to set IV in ctx via AES_init_ctx_iv() or AES_ctx_set_iv()
+// no IV should ever be reused with the same key
+void AES_CBC_encrypt_buffer(struct AES_ctx* ctx, uint8_t* buf, uint32_t length);
+void AES_CBC_decrypt_buffer(struct AES_ctx* ctx, uint8_t* buf, uint32_t length);
+
+#endif // #if defined(CBC) && (CBC == 1)
+
+
+#if defined(CTR) && (CTR == 1)
+
+// Same function for encrypting as for decrypting.
+// IV is incremented for every block, and used after encryption as XOR-compliment for output
+// Suggesting https://en.wikipedia.org/wiki/Padding_(cryptography)#PKCS7 for padding scheme
+// NOTES: you need to set IV in ctx with AES_init_ctx_iv() or AES_ctx_set_iv()
+// no IV should ever be reused with the same key
+void AES_CTR_xcrypt_buffer(struct AES_ctx* ctx, uint8_t* buf, uint32_t length);
+
+#endif // #if defined(CTR) && (CTR == 1)
+
+
+#endif //_AES_H_