Overview

This repository houses a standard AES-192 ECB (Electronic Codebook) encryption algorithm implemented in C. AES-192 is known for its enhanced security.

Features

• AES-192 ECB: Implements AES-192 ECB encryption mode for secure data processing.

• Fixed Block Size: Enforces a fixed 16-byte block size without padding.

• Compatibility: Encrypted data is interoperable with any AES-192 ECB decryption.

Usage

Include "AES_192_ECB.h" before using the AES-192 ECB functions.

#include "AES_192_ECB.h"

AES Context Initialization

AES_CTX ctx;

Initialize Encryption

AES_EncryptInit(&ctx, key);

Encryption Function

AES_Encrypt(&ctx, plaintext, ciphertext);

The AES_Encrypt function is designed to encrypt a single 16-byte block of data.

Encryption Function for Multiple Blocks

If your data is in multiple blocks, it is recommended to use a loop to encrypt each block individually:

for (unsigned int offset = 0; offset < multiple_block_size; offset += AES_BLOCK_SIZE) {
    AES_Encrypt(&ctx, plaintext + offset, ciphertext + offset);
}

This loop allows you to encrypt each 16-byte block of data individually when dealing with data spanning multiple blocks. Remember that each block must be exactly 16 bytes in size for proper encryption.

Initialize Decryption

AES_DecryptInit(&ctx, key);

Decryption Function

AES_Decrypt(&ctx, ciphertext, plaintext);

The AES_Decrypt function is designed to decrypt a single 16-byte block of data.

Completion

AES_CTX_Free(&ctx);

Example Code (main.c)

#include <stdio.h>
#include "AES_192_ECB.h"

int main() {
    AES_CTX ctx;
    uint8_t key[AES_KEY_SIZE];
    uint8_t data[AES_BLOCK_SIZE * 3]; // Example data with three blocks
    
    // Initialization and usage example
    memcpy(key, "This is aes key!", AES_KEY_SIZE);
    memcpy(data, "This is test msg123456", AES_BLOCK_SIZE * 3);
    
    printf("Original:  ");
    for (unsigned int index = 0; index < AES_BLOCK_SIZE * 3; index++) {
        printf("%02X", data[index]);
    }
    printf("\n");
    
    AES_EncryptInit(&ctx, key);
    
    for (unsigned int offset = 0; offset < AES_BLOCK_SIZE * 3; offset += AES_BLOCK_SIZE) {
        AES_Encrypt(&ctx, data + offset, data + offset);
    }
    
    printf("Encrypted: ");
    for (unsigned int index = 0; index < AES_BLOCK_SIZE * 3; index++) {
        printf("%02X", data[index]);
    }
    printf("\n");
    
    AES_DecryptInit(&ctx, key);
    
    for (unsigned int offset = 0; offset < AES_BLOCK_SIZE * 3; offset += AES_BLOCK_SIZE) {
        AES_Decrypt(&ctx, data + offset, data + offset);
    }
    
    printf("Decrypted: ");
    for (unsigned int index = 0; index < AES_BLOCK_SIZE * 3; index++) {
        printf("%02X", data[index]);
    }
    printf("\n");
    
    AES_CTX_Free(&ctx);
    return 0;
}

Contributions

Contributions and feedback are welcome! Open issues or submit pull requests.

License

This AES-192 ECB implementation is provided under the MIT License.