1 /**
2 * \file block_cipher_internal.h
3 *
4 * \brief Lightweight abstraction layer for block ciphers with 128 bit blocks,
5 * for use by the GCM and CCM modules.
6 */
7 /*
8 * Copyright The Mbed TLS Contributors
9 * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
10 */
11 #ifndef MBEDTLS_BLOCK_CIPHER_INTERNAL_H
12 #define MBEDTLS_BLOCK_CIPHER_INTERNAL_H
13
14 #include "mbedtls/build_info.h"
15
16 #include "mbedtls/cipher.h"
17
18 #include "mbedtls/block_cipher.h"
19
20 #ifdef __cplusplus
21 extern "C" {
22 #endif
23
24 /**
25 * \brief Initialize the context.
26 * This must be the first API call before using the context.
27 *
28 * \param ctx The context to initialize.
29 */
mbedtls_block_cipher_init(mbedtls_block_cipher_context_t * ctx)30 static inline void mbedtls_block_cipher_init(mbedtls_block_cipher_context_t *ctx)
31 {
32 memset(ctx, 0, sizeof(*ctx));
33 }
34
35 /**
36 * \brief Set the block cipher to use with this context.
37 * This must be called after mbedtls_block_cipher_init().
38 *
39 * \param ctx The context to set up.
40 * \param cipher_id The identifier of the cipher to use.
41 * This must be either AES, ARIA or Camellia.
42 * Warning: this is a ::mbedtls_cipher_id_t,
43 * not a ::mbedtls_block_cipher_id_t!
44 *
45 * \retval \c 0 on success.
46 * \retval #MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA if \p cipher_id was
47 * invalid.
48 */
49 int mbedtls_block_cipher_setup(mbedtls_block_cipher_context_t *ctx,
50 mbedtls_cipher_id_t cipher_id);
51
52 /**
53 * \brief Set the key into the context.
54 *
55 * \param ctx The context to configure.
56 * \param key The buffer holding the key material.
57 * \param key_bitlen The size of the key in bits.
58 *
59 * \retval \c 0 on success.
60 * \retval #MBEDTLS_ERR_CIPHER_INVALID_CONTEXT if the context was not
61 * properly set up before calling this function.
62 * \retval One of #MBEDTLS_ERR_AES_INVALID_KEY_LENGTH,
63 * #MBEDTLS_ERR_ARIA_BAD_INPUT_DATA,
64 * #MBEDTLS_ERR_CAMELLIA_BAD_INPUT_DATA if \p key_bitlen is
65 * invalid.
66 */
67 int mbedtls_block_cipher_setkey(mbedtls_block_cipher_context_t *ctx,
68 const unsigned char *key,
69 unsigned key_bitlen);
70
71 /**
72 * \brief Encrypt one block (16 bytes) with the configured key.
73 *
74 * \param ctx The context holding the key.
75 * \param input The buffer holding the input block. Must be 16 bytes.
76 * \param output The buffer to which the output block will be written.
77 * Must be writable and 16 bytes long.
78 * This must either not overlap with \p input, or be equal.
79 *
80 * \retval \c 0 on success.
81 * \retval #MBEDTLS_ERR_CIPHER_INVALID_CONTEXT if the context was not
82 * properly set up before calling this function.
83 * \retval Another negative value if encryption failed.
84 */
85 int mbedtls_block_cipher_encrypt(mbedtls_block_cipher_context_t *ctx,
86 const unsigned char input[16],
87 unsigned char output[16]);
88 /**
89 * \brief Clear the context.
90 *
91 * \param ctx The context to clear.
92 */
93 void mbedtls_block_cipher_free(mbedtls_block_cipher_context_t *ctx);
94
95 #ifdef __cplusplus
96 }
97 #endif
98
99 #endif /* MBEDTLS_BLOCK_CIPHER_INTERNAL_H */
100
