michael@0: /*
michael@0:  * null_cipher.c
michael@0:  *
michael@0:  * A null cipher implementation.  This cipher leaves the plaintext
michael@0:  * unchanged.
michael@0:  *
michael@0:  * David A. McGrew
michael@0:  * Cisco Systems, Inc.
michael@0:  */
michael@0: 
michael@0: /*
michael@0:  *	
michael@0:  * Copyright (c) 2001-2006, Cisco Systems, Inc.
michael@0:  * All rights reserved.
michael@0:  * 
michael@0:  * Redistribution and use in source and binary forms, with or without
michael@0:  * modification, are permitted provided that the following conditions
michael@0:  * are met:
michael@0:  * 
michael@0:  *   Redistributions of source code must retain the above copyright
michael@0:  *   notice, this list of conditions and the following disclaimer.
michael@0:  * 
michael@0:  *   Redistributions in binary form must reproduce the above
michael@0:  *   copyright notice, this list of conditions and the following
michael@0:  *   disclaimer in the documentation and/or other materials provided
michael@0:  *   with the distribution.
michael@0:  * 
michael@0:  *   Neither the name of the Cisco Systems, Inc. nor the names of its
michael@0:  *   contributors may be used to endorse or promote products derived
michael@0:  *   from this software without specific prior written permission.
michael@0:  * 
michael@0:  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
michael@0:  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
michael@0:  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
michael@0:  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
michael@0:  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
michael@0:  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
michael@0:  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
michael@0:  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
michael@0:  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
michael@0:  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
michael@0:  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
michael@0:  * OF THE POSSIBILITY OF SUCH DAMAGE.
michael@0:  *
michael@0:  */
michael@0: 
michael@0: #include "datatypes.h"
michael@0: #include "null_cipher.h"
michael@0: #include "alloc.h"
michael@0: 
michael@0: /* the null_cipher uses the cipher debug module  */
michael@0: 
michael@0: extern debug_module_t mod_cipher;
michael@0: 
michael@0: err_status_t
michael@0: null_cipher_alloc(cipher_t **c, int key_len) {
michael@0:   extern cipher_type_t null_cipher;
michael@0:   uint8_t *pointer;
michael@0:   
michael@0:   debug_print(mod_cipher, 
michael@0: 	      "allocating cipher with key length %d", key_len);
michael@0: 
michael@0:   /* allocate memory a cipher of type null_cipher */
michael@0:   pointer = (uint8_t*)crypto_alloc(sizeof(null_cipher_ctx_t) + sizeof(cipher_t));
michael@0:   if (pointer == NULL)
michael@0:     return err_status_alloc_fail;
michael@0: 
michael@0:   /* set pointers */
michael@0:   *c = (cipher_t *)pointer;
michael@0:   (*c)->type = &null_cipher;
michael@0:   (*c)->state = pointer + sizeof(cipher_t);
michael@0: 
michael@0:   /* set key size */
michael@0:   (*c)->key_len = key_len;
michael@0: 
michael@0:   /* increment ref_count */
michael@0:   null_cipher.ref_count++;
michael@0:   
michael@0:   return err_status_ok;
michael@0:   
michael@0: }
michael@0: 
michael@0: err_status_t
michael@0: null_cipher_dealloc(cipher_t *c) {
michael@0:   extern cipher_type_t null_cipher;
michael@0: 
michael@0:   /* zeroize entire state*/
michael@0:   octet_string_set_to_zero((uint8_t *)c, 
michael@0: 			   sizeof(null_cipher_ctx_t) + sizeof(cipher_t));
michael@0: 
michael@0:   /* free memory of type null_cipher */
michael@0:   crypto_free(c);
michael@0: 
michael@0:   /* decrement reference count */
michael@0:   null_cipher.ref_count--;
michael@0:   
michael@0:   return err_status_ok;
michael@0:   
michael@0: }
michael@0: 
michael@0: err_status_t
michael@0: null_cipher_init(null_cipher_ctx_t *ctx, const uint8_t *key, int key_len) {
michael@0: 
michael@0:   debug_print(mod_cipher, "initializing null cipher", NULL);
michael@0: 
michael@0:   return err_status_ok;
michael@0: }
michael@0: 
michael@0: err_status_t
michael@0: null_cipher_set_iv(null_cipher_ctx_t *c, void *iv) { 
michael@0:   return err_status_ok;
michael@0: }
michael@0: 
michael@0: err_status_t
michael@0: null_cipher_encrypt(null_cipher_ctx_t *c,
michael@0: 		    unsigned char *buf, unsigned int *bytes_to_encr) {
michael@0:   return err_status_ok;
michael@0: }
michael@0: 
michael@0: char 
michael@0: null_cipher_description[] = "null cipher";
michael@0: 
michael@0: cipher_test_case_t  
michael@0: null_cipher_test_0 = {
michael@0:   0,                 /* octets in key            */
michael@0:   NULL,              /* key                      */
michael@0:   0,                 /* packet index             */
michael@0:   0,                 /* octets in plaintext      */
michael@0:   NULL,              /* plaintext                */
michael@0:   0,                 /* octets in plaintext      */
michael@0:   NULL,              /* ciphertext               */
michael@0:   NULL               /* pointer to next testcase */
michael@0: };
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * note: the decrypt function is idential to the encrypt function
michael@0:  */
michael@0: 
michael@0: cipher_type_t null_cipher = {
michael@0:   (cipher_alloc_func_t)         null_cipher_alloc,
michael@0:   (cipher_dealloc_func_t)       null_cipher_dealloc,
michael@0:   (cipher_init_func_t)          null_cipher_init,
michael@0:   (cipher_encrypt_func_t)       null_cipher_encrypt,
michael@0:   (cipher_decrypt_func_t)       null_cipher_encrypt,
michael@0:   (cipher_set_iv_func_t)        null_cipher_set_iv,
michael@0:   (char *)                      null_cipher_description,
michael@0:   (int)                         0,
michael@0:   (cipher_test_case_t *)       &null_cipher_test_0,
michael@0:   (debug_module_t *)            NULL,
michael@0:   (cipher_type_id_t)            NULL_CIPHER
michael@0: };
michael@0: