Adding Block Encryption Algorithms

The required constant definitions are as follows:

#define MODULE_NAME AES	       /* Name of algorithm */
#define BLOCK_SIZE 16          /* Size of encryption block */
#define KEY_SIZE 0             /* Size of key in bytes (0 if not fixed size) */

The C structure must be named block_state:

typedef struct {
     ... whatever state variables you need ...
} block_state;

There are three functions that need to be written: to initialize the algorithm's state, and to encrypt and decrypt a single block.

• void block_init(block_state *self, unsigned char *key, int keylen);
• void block_encrypt(block_state *self, unsigned char *in, unsigned char *out);
• void block_decrypt(block_state *self, unsigned char *in, unsigned char *out);

Put #include "block_template.c" at the end of the file to include the actual implementation of the module.