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Dependencies: nRF51_Vdd TextLCD BME280
nist_kw.h File Reference
This file provides an API for key wrapping (KW) and key wrapping with padding (KWP) as defined in NIST SP 800-38F. More...
Go to the source code of this file.
Data Structures | |
struct | mbedtls_nist_kw_context |
The key wrapping context-type definition. More... | |
Functions | |
void | mbedtls_nist_kw_init (mbedtls_nist_kw_context *ctx) |
This function initializes the specified key wrapping context to make references valid and prepare the context for mbedtls_nist_kw_setkey() or mbedtls_nist_kw_free(). | |
int | mbedtls_nist_kw_setkey (mbedtls_nist_kw_context *ctx, mbedtls_cipher_id_t cipher, const unsigned char *key, unsigned int keybits, const int is_wrap) |
This function initializes the key wrapping context set in the ctx parameter and sets the encryption key. | |
void | mbedtls_nist_kw_free (mbedtls_nist_kw_context *ctx) |
This function releases and clears the specified key wrapping context and underlying cipher sub-context. | |
int | mbedtls_nist_kw_wrap (mbedtls_nist_kw_context *ctx, mbedtls_nist_kw_mode_t mode, const unsigned char *input, size_t in_len, unsigned char *output, size_t *out_len, size_t out_size) |
This function encrypts a buffer using key wrapping. | |
int | mbedtls_nist_kw_unwrap (mbedtls_nist_kw_context *ctx, mbedtls_nist_kw_mode_t mode, const unsigned char *input, size_t in_len, unsigned char *output, size_t *out_len, size_t out_size) |
This function decrypts a buffer using key wrapping. | |
int | mbedtls_nist_kw_self_test (int verbose) |
The key wrapping checkup routine. |
Detailed Description
This file provides an API for key wrapping (KW) and key wrapping with padding (KWP) as defined in NIST SP 800-38F.
https://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.800-38F.pdf
Key wrapping specifies a deterministic authenticated-encryption mode of operation, according to NIST SP 800-38F: Recommendation for Block Cipher Modes of Operation: Methods for Key Wrapping. Its purpose is to protect cryptographic keys.
Its equivalent is RFC 3394 for KW, and RFC 5649 for KWP. https://tools.ietf.org/html/rfc3394 https://tools.ietf.org/html/rfc5649
Definition in file nist_kw.h.
Function Documentation
void mbedtls_nist_kw_free | ( | mbedtls_nist_kw_context * | ctx ) |
void mbedtls_nist_kw_init | ( | mbedtls_nist_kw_context * | ctx ) |
This function initializes the specified key wrapping context to make references valid and prepare the context for mbedtls_nist_kw_setkey() or mbedtls_nist_kw_free().
- Parameters:
-
ctx The key wrapping context to initialize.
int mbedtls_nist_kw_self_test | ( | int | verbose ) |
int mbedtls_nist_kw_setkey | ( | mbedtls_nist_kw_context * | ctx, |
mbedtls_cipher_id_t | cipher, | ||
const unsigned char * | key, | ||
unsigned int | keybits, | ||
const int | is_wrap | ||
) |
This function initializes the key wrapping context set in the ctx
parameter and sets the encryption key.
- Parameters:
-
ctx The key wrapping context. cipher The 128-bit block cipher to use. Only AES is supported. key The Key Encryption Key (KEK). keybits The KEK size in bits. This must be acceptable by the cipher. is_wrap Specify whether the operation within the context is wrapping or unwrapping
- Returns:
0
on success.-
MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA
for any invalid input. -
MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE
for 128-bit block ciphers which are not supported. - cipher-specific error code on failure of the underlying cipher.
int mbedtls_nist_kw_unwrap | ( | mbedtls_nist_kw_context * | ctx, |
mbedtls_nist_kw_mode_t | mode, | ||
const unsigned char * | input, | ||
size_t | in_len, | ||
unsigned char * | output, | ||
size_t * | out_len, | ||
size_t | out_size | ||
) |
This function decrypts a buffer using key wrapping.
- Parameters:
-
ctx The key wrapping context to use for decryption. mode The key wrapping mode to use (MBEDTLS_KW_MODE_KW or MBEDTLS_KW_MODE_KWP) input The buffer holding the input data. in_len The length of the input data in Bytes. The input uses units of 8 Bytes called semiblocks. The input must be a multiple of semiblocks. - For KW mode: a multiple of 8 bytes between 24 and 2^57 inclusive.
- For KWP mode: a multiple of 8 bytes between 16 and 2^32 inclusive.
[out] output The buffer holding the output data. The output buffer's minimal length is 8 bytes shorter than in_len
.[out] out_len The number of bytes written to the output buffer. 0
on failure. For KWP mode, the length could be up to 15 bytes shorter thanin_len
, depending on how much padding was added to the data.[in] out_size The capacity of the output buffer.
- Returns:
0
on success.-
MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA
for invalid input length. -
MBEDTLS_ERR_CIPHER_AUTH_FAILED
for verification failure of the ciphertext. - cipher-specific error code on failure of the underlying cipher.
int mbedtls_nist_kw_wrap | ( | mbedtls_nist_kw_context * | ctx, |
mbedtls_nist_kw_mode_t | mode, | ||
const unsigned char * | input, | ||
size_t | in_len, | ||
unsigned char * | output, | ||
size_t * | out_len, | ||
size_t | out_size | ||
) |
This function encrypts a buffer using key wrapping.
- Parameters:
-
ctx The key wrapping context to use for encryption. mode The key wrapping mode to use (MBEDTLS_KW_MODE_KW or MBEDTLS_KW_MODE_KWP) input The buffer holding the input data. in_len The length of the input data in Bytes. The input uses units of 8 Bytes called semiblocks. - For KW mode: a multiple of 8 bytes between 16 and 2^57-8 inclusive.
- For KWP mode: any length between 1 and 2^32-1 inclusive.
[out] output The buffer holding the output data. -
For KW mode: Must be at least 8 bytes larger than
in_len
. - For KWP mode: Must be at least 8 bytes larger rounded up to a multiple of 8 bytes for KWP (15 bytes at most).
[out] out_len The number of bytes written to the output buffer. 0
on failure.[in] out_size The capacity of the output buffer.
- Returns:
0
on success.-
MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA
for invalid input length. - cipher-specific error code on failure of the underlying cipher.
Generated on Tue Jul 12 2022 15:16:07 by
