| Index: crypto/cipher/null_cipher.c
|
| diff --git a/crypto/cipher/null_cipher.c b/crypto/cipher/null_cipher.c
|
| new file mode 100644
|
| index 0000000000000000000000000000000000000000..4dc71afbe415aa1cae4874c6c3c7da6fc6acdbf5
|
| --- /dev/null
|
| +++ b/crypto/cipher/null_cipher.c
|
| @@ -0,0 +1,156 @@
|
| +/*
|
| + * null_cipher.c
|
| + *
|
| + * A null cipher implementation. This cipher leaves the plaintext
|
| + * unchanged.
|
| + *
|
| + * David A. McGrew
|
| + * Cisco Systems, Inc.
|
| + */
|
| +
|
| +/*
|
| + *
|
| + * Copyright (c) 2001-2006,2013 Cisco Systems, Inc.
|
| + * All rights reserved.
|
| + *
|
| + * Redistribution and use in source and binary forms, with or without
|
| + * modification, are permitted provided that the following conditions
|
| + * are met:
|
| + *
|
| + * Redistributions of source code must retain the above copyright
|
| + * notice, this list of conditions and the following disclaimer.
|
| + *
|
| + * Redistributions in binary form must reproduce the above
|
| + * copyright notice, this list of conditions and the following
|
| + * disclaimer in the documentation and/or other materials provided
|
| + * with the distribution.
|
| + *
|
| + * Neither the name of the Cisco Systems, Inc. nor the names of its
|
| + * contributors may be used to endorse or promote products derived
|
| + * from this software without specific prior written permission.
|
| + *
|
| + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
| + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
| + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
|
| + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
|
| + * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
|
| + * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
|
| + * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
|
| + * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
| + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
|
| + * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
|
| + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
|
| + * OF THE POSSIBILITY OF SUCH DAMAGE.
|
| + *
|
| + */
|
| +
|
| +#ifdef HAVE_CONFIG_H
|
| + #include <config.h>
|
| +#endif
|
| +
|
| +#include "datatypes.h"
|
| +#include "null_cipher.h"
|
| +#include "err.h" /* for srtp_debug */
|
| +#include "alloc.h"
|
| +
|
| +/* the null_cipher uses the cipher debug module */
|
| +
|
| +extern srtp_debug_module_t srtp_mod_cipher;
|
| +
|
| +static srtp_err_status_t srtp_null_cipher_alloc (srtp_cipher_t **c, int key_len, int tlen)
|
| +{
|
| + extern const srtp_cipher_type_t srtp_null_cipher;
|
| +
|
| + debug_print(srtp_mod_cipher,
|
| + "allocating cipher with key length %d", key_len);
|
| +
|
| + /* allocate memory a cipher of type null_cipher */
|
| + *c = (srtp_cipher_t *)srtp_crypto_alloc(sizeof(srtp_cipher_t));
|
| + if (*c == NULL) {
|
| + return srtp_err_status_alloc_fail;
|
| + }
|
| + memset(*c, 0x0, sizeof(srtp_cipher_t));
|
| +
|
| + /* set pointers */
|
| + (*c)->algorithm = SRTP_NULL_CIPHER;
|
| + (*c)->type = &srtp_null_cipher;
|
| + (*c)->state = (void *) 0x1; /* The null cipher does not maintain state */
|
| +
|
| + /* set key size */
|
| + (*c)->key_len = key_len;
|
| +
|
| + return srtp_err_status_ok;
|
| +
|
| +}
|
| +
|
| +static srtp_err_status_t srtp_null_cipher_dealloc (srtp_cipher_t *c)
|
| +{
|
| + extern const srtp_cipher_type_t srtp_null_cipher;
|
| +
|
| + /* zeroize entire state*/
|
| + octet_string_set_to_zero((uint8_t*)c, sizeof(srtp_cipher_t));
|
| +
|
| + /* free memory of type null_cipher */
|
| + srtp_crypto_free(c);
|
| +
|
| + return srtp_err_status_ok;
|
| +
|
| +}
|
| +
|
| +static srtp_err_status_t srtp_null_cipher_init (void *cv, const uint8_t *key)
|
| +{
|
| + /* srtp_null_cipher_ctx_t *c = (srtp_null_cipher_ctx_t *)cv; */
|
| +
|
| + debug_print(srtp_mod_cipher, "initializing null cipher", NULL);
|
| +
|
| + return srtp_err_status_ok;
|
| +}
|
| +
|
| +static srtp_err_status_t srtp_null_cipher_set_iv (void *cv, uint8_t *iv, srtp_cipher_direction_t dir)
|
| +{
|
| + /* srtp_null_cipher_ctx_t *c = (srtp_null_cipher_ctx_t *)cv; */
|
| + return srtp_err_status_ok;
|
| +}
|
| +
|
| +static srtp_err_status_t srtp_null_cipher_encrypt (void *cv,
|
| + unsigned char *buf, unsigned int *bytes_to_encr)
|
| +{
|
| + /* srtp_null_cipher_ctx_t *c = (srtp_null_cipher_ctx_t *)cv; */
|
| + return srtp_err_status_ok;
|
| +}
|
| +
|
| +static const char srtp_null_cipher_description[] = "null cipher";
|
| +
|
| +static const srtp_cipher_test_case_t srtp_null_cipher_test_0 = {
|
| + 0, /* octets in key */
|
| + NULL, /* key */
|
| + 0, /* packet index */
|
| + 0, /* octets in plaintext */
|
| + NULL, /* plaintext */
|
| + 0, /* octets in plaintext */
|
| + NULL, /* ciphertext */
|
| + 0,
|
| + NULL,
|
| + 0,
|
| + NULL /* pointer to next testcase */
|
| +};
|
| +
|
| +
|
| +/*
|
| + * note: the decrypt function is idential to the encrypt function
|
| + */
|
| +
|
| +const srtp_cipher_type_t srtp_null_cipher = {
|
| + srtp_null_cipher_alloc,
|
| + srtp_null_cipher_dealloc,
|
| + srtp_null_cipher_init,
|
| + 0, /* set_aad */
|
| + srtp_null_cipher_encrypt,
|
| + srtp_null_cipher_encrypt,
|
| + srtp_null_cipher_set_iv,
|
| + 0, /* get_tag */
|
| + srtp_null_cipher_description,
|
| + &srtp_null_cipher_test_0,
|
| + SRTP_NULL_CIPHER
|
| +};
|
| +
|
|
|