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Diffstat (limited to 'netwerk/srtp/src/crypto/include/cipher.h')
| -rw-r--r-- | netwerk/srtp/src/crypto/include/cipher.h | 230 |
1 files changed, 230 insertions, 0 deletions
diff --git a/netwerk/srtp/src/crypto/include/cipher.h b/netwerk/srtp/src/crypto/include/cipher.h new file mode 100644 index 000000000..eff6dd154 --- /dev/null +++ b/netwerk/srtp/src/crypto/include/cipher.h @@ -0,0 +1,230 @@ +/* + * cipher.h + * + * common interface to ciphers + * + * David A. McGrew + * Cisco Systems, Inc. + */ +/* + * + * Copyright (c) 2001-2006, 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. + * + */ + + +#ifndef CIPHER_H +#define CIPHER_H + +#include "datatypes.h" +#include "rdbx.h" /* for xtd_seq_num_t */ +#include "err.h" /* for error codes */ +#include "crypto.h" /* for cipher_type_id_t */ +#include "crypto_types.h" /* for values of cipher_type_id_t */ + + +/** + * @brief cipher_direction_t defines a particular cipher operation. + * + * A cipher_direction_t is an enum that describes a particular cipher + * operation, i.e. encryption or decryption. For some ciphers, this + * distinction does not matter, but for others, it is essential. + */ + +typedef enum { + direction_encrypt, /**< encryption (convert plaintext to ciphertext) */ + direction_decrypt, /**< decryption (convert ciphertext to plaintext) */ + direction_any /**< encryption or decryption */ +} cipher_direction_t; + +/* + * the cipher_pointer and cipher_type_pointer definitions are needed + * as cipher_t and cipher_type_t are not yet defined + */ + +typedef struct cipher_type_t *cipher_type_pointer_t; +typedef struct cipher_t *cipher_pointer_t; + +/* + * a cipher_alloc_func_t allocates (but does not initialize) a cipher_t + */ + +typedef err_status_t (*cipher_alloc_func_t) + (cipher_pointer_t *cp, int key_len); + +/* + * a cipher_init_func_t [re-]initializes a cipher_t with a given key + * and direction (i.e., encrypt or decrypt) + */ + +typedef err_status_t (*cipher_init_func_t) +(void *state, const uint8_t *key, int key_len, cipher_direction_t dir); + +/* a cipher_dealloc_func_t de-allocates a cipher_t */ + +typedef err_status_t (*cipher_dealloc_func_t)(cipher_pointer_t cp); + +/* a cipher_set_segment_func_t sets the segment index of a cipher_t */ + +typedef err_status_t (*cipher_set_segment_func_t) + (void *state, xtd_seq_num_t idx); + +/* a cipher_encrypt_func_t encrypts data in-place */ + +typedef err_status_t (*cipher_encrypt_func_t) + (void *state, uint8_t *buffer, unsigned int *octets_to_encrypt); + +/* a cipher_decrypt_func_t decrypts data in-place */ + +typedef err_status_t (*cipher_decrypt_func_t) + (void *state, uint8_t *buffer, unsigned int *octets_to_decrypt); + +/* + * a cipher_set_iv_func_t function sets the current initialization vector + */ + +typedef err_status_t (*cipher_set_iv_func_t) + (cipher_pointer_t cp, void *iv); + +/* + * cipher_test_case_t is a (list of) key, salt, xtd_seq_num_t, + * plaintext, and ciphertext values that are known to be correct for a + * particular cipher. this data can be used to test an implementation + * in an on-the-fly self test of the correcness of the implementation. + * (see the cipher_type_self_test() function below) + */ + +typedef struct cipher_test_case_t { + int key_length_octets; /* octets in key */ + uint8_t *key; /* key */ + uint8_t *idx; /* packet index */ + int plaintext_length_octets; /* octets in plaintext */ + uint8_t *plaintext; /* plaintext */ + int ciphertext_length_octets; /* octets in plaintext */ + uint8_t *ciphertext; /* ciphertext */ + struct cipher_test_case_t *next_test_case; /* pointer to next testcase */ +} cipher_test_case_t; + +/* cipher_type_t defines the 'metadata' for a particular cipher type */ + +typedef struct cipher_type_t { + cipher_alloc_func_t alloc; + cipher_dealloc_func_t dealloc; + cipher_init_func_t init; + cipher_encrypt_func_t encrypt; + cipher_encrypt_func_t decrypt; + cipher_set_iv_func_t set_iv; + char *description; + int ref_count; + cipher_test_case_t *test_data; + debug_module_t *debug; + cipher_type_id_t id; +} cipher_type_t; + +/* + * cipher_t defines an instantiation of a particular cipher, with fixed + * key length, key and salt values + */ + +typedef struct cipher_t { + cipher_type_t *type; + void *state; + int key_len; +#ifdef FORCE_64BIT_ALIGN + int pad; +#endif +} cipher_t; + +/* some syntactic sugar on these function types */ + +#define cipher_type_alloc(ct, c, klen) ((ct)->alloc((c), (klen))) + +#define cipher_dealloc(c) (((c)->type)->dealloc(c)) + +#define cipher_init(c, k, dir) (((c)->type)->init(((c)->state), (k), ((c)->key_len), (dir))) + +#define cipher_encrypt(c, buf, len) \ + (((c)->type)->encrypt(((c)->state), (buf), (len))) + +#define cipher_decrypt(c, buf, len) \ + (((c)->type)->decrypt(((c)->state), (buf), (len))) + +#define cipher_set_iv(c, n) \ + ((c) ? (((c)->type)->set_iv(((cipher_pointer_t)(c)->state), (n))) : \ + err_status_no_such_op) + +err_status_t +cipher_output(cipher_t *c, uint8_t *buffer, int num_octets_to_output); + + +/* some bookkeeping functions */ + +int +cipher_get_key_length(const cipher_t *c); + + +/* + * cipher_type_self_test() tests a cipher against test cases provided in + * an array of values of key/xtd_seq_num_t/plaintext/ciphertext + * that is known to be good + */ + +err_status_t +cipher_type_self_test(const cipher_type_t *ct); + + +/* + * cipher_type_test() tests a cipher against external test cases provided in + * an array of values of key/xtd_seq_num_t/plaintext/ciphertext + * that is known to be good + */ + +err_status_t +cipher_type_test(const cipher_type_t *ct, const cipher_test_case_t *test_data); + + +/* + * cipher_bits_per_second(c, l, t) computes (and estimate of) the + * number of bits that a cipher implementation can encrypt in a second + * + * c is a cipher (which MUST be allocated and initialized already), l + * is the length in octets of the test data to be encrypted, and t is + * the number of trials + * + * if an error is encountered, then the value 0 is returned + */ + +uint64_t +cipher_bits_per_second(cipher_t *c, int octets_in_buffer, int num_trials); + +#endif /* CIPHER_H */ |