Detailed Description
Generic cipher wrapper.
Copyright (C) 2006-2015, ARM Limited, All Rights Reserved SPDX-License-Identifier: Apache-2.0
Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
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This file is part of mbed TLS (https://tls.mbed.org)
Definition in file cipher.h.
Go to the source code of this file.
Data Structures | |
| struct | mbedtls_cipher_info_t |
| Cipher information. More... | |
| struct | mbedtls_cipher_context_t |
| Generic cipher context. More... | |
Macros | |
| #define | MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE -0x6080 |
| The selected feature is not available. More... | |
| #define | MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA -0x6100 |
| Bad input parameters to function. More... | |
| #define | MBEDTLS_ERR_CIPHER_ALLOC_FAILED -0x6180 |
| Failed to allocate memory. More... | |
| #define | MBEDTLS_ERR_CIPHER_INVALID_PADDING -0x6200 |
| Input data contains invalid padding and is rejected. More... | |
| #define | MBEDTLS_ERR_CIPHER_FULL_BLOCK_EXPECTED -0x6280 |
| Decryption of block requires a full block. More... | |
| #define | MBEDTLS_ERR_CIPHER_AUTH_FAILED -0x6300 |
| Authentication failed (for AEAD modes). More... | |
| #define | MBEDTLS_CIPHER_VARIABLE_IV_LEN 0x01 |
| Cipher accepts IVs of variable length. More... | |
| #define | MBEDTLS_CIPHER_VARIABLE_KEY_LEN 0x02 |
| Cipher accepts keys of variable length. More... | |
| #define | MBEDTLS_MAX_IV_LENGTH 16 |
| Maximum length of any IV, in bytes. More... | |
| #define | MBEDTLS_MAX_BLOCK_LENGTH 16 |
| Maximum block size of any cipher, in bytes. More... | |
Typedefs | |
| typedef struct mbedtls_cipher_base_t | mbedtls_cipher_base_t |
| Base cipher information (opaque struct). More... | |
Functions | |
| const int * | mbedtls_cipher_list (void) |
| Returns the list of ciphers supported by the generic cipher module. More... | |
| const mbedtls_cipher_info_t * | mbedtls_cipher_info_from_string (const char *cipher_name) |
| Returns the cipher information structure associated with the given cipher name. More... | |
| const mbedtls_cipher_info_t * | mbedtls_cipher_info_from_type (const mbedtls_cipher_type_t cipher_type) |
| Returns the cipher information structure associated with the given cipher type. More... | |
| const mbedtls_cipher_info_t * | mbedtls_cipher_info_from_values (const mbedtls_cipher_id_t cipher_id, int key_bitlen, const mbedtls_cipher_mode_t mode) |
| Returns the cipher information structure associated with the given cipher id, key size and mode. More... | |
| void | mbedtls_cipher_init (mbedtls_cipher_context_t *ctx) |
| Initialize a cipher_context (as NONE) More... | |
| void | mbedtls_cipher_free (mbedtls_cipher_context_t *ctx) |
| Free and clear the cipher-specific context of ctx. More... | |
| int | mbedtls_cipher_setup (mbedtls_cipher_context_t *ctx, const mbedtls_cipher_info_t *cipher_info) |
| Initialises and fills the cipher context structure with the appropriate values. More... | |
| static unsigned int | mbedtls_cipher_get_block_size (const mbedtls_cipher_context_t *ctx) |
| Returns the block size of the given cipher. More... | |
| static mbedtls_cipher_mode_t | mbedtls_cipher_get_cipher_mode (const mbedtls_cipher_context_t *ctx) |
| Returns the mode of operation for the cipher. More... | |
| static int | mbedtls_cipher_get_iv_size (const mbedtls_cipher_context_t *ctx) |
| Returns the size of the cipher's IV/NONCE in bytes. More... | |
| static mbedtls_cipher_type_t | mbedtls_cipher_get_type (const mbedtls_cipher_context_t *ctx) |
| Returns the type of the given cipher. More... | |
| static const char * | mbedtls_cipher_get_name (const mbedtls_cipher_context_t *ctx) |
| Returns the name of the given cipher, as a string. More... | |
| static int | mbedtls_cipher_get_key_bitlen (const mbedtls_cipher_context_t *ctx) |
| Returns the key length of the cipher. More... | |
| static mbedtls_operation_t | mbedtls_cipher_get_operation (const mbedtls_cipher_context_t *ctx) |
| Returns the operation of the given cipher. More... | |
| int | mbedtls_cipher_setkey (mbedtls_cipher_context_t *ctx, const unsigned char *key, int key_bitlen, const mbedtls_operation_t operation) |
| Set the key to use with the given context. More... | |
| int | mbedtls_cipher_set_iv (mbedtls_cipher_context_t *ctx, const unsigned char *iv, size_t iv_len) |
| Set the initialization vector (IV) or nonce. More... | |
| int | mbedtls_cipher_reset (mbedtls_cipher_context_t *ctx) |
| Finish preparation of the given context. More... | |
| int | mbedtls_cipher_update (mbedtls_cipher_context_t *ctx, const unsigned char *input, size_t ilen, unsigned char *output, size_t *olen) |
| Generic cipher update function. More... | |
| int | mbedtls_cipher_finish (mbedtls_cipher_context_t *ctx, unsigned char *output, size_t *olen) |
| Generic cipher finalisation function. More... | |
| int | mbedtls_cipher_crypt (mbedtls_cipher_context_t *ctx, const unsigned char *iv, size_t iv_len, const unsigned char *input, size_t ilen, unsigned char *output, size_t *olen) |
| Generic all-in-one encryption/decryption (for all ciphers except AEAD constructs). More... | |
Macro Definition Documentation
| #define MBEDTLS_CIPHER_VARIABLE_IV_LEN 0x01 |
| #define MBEDTLS_CIPHER_VARIABLE_KEY_LEN 0x02 |
| #define MBEDTLS_ERR_CIPHER_ALLOC_FAILED -0x6180 |
| #define MBEDTLS_ERR_CIPHER_AUTH_FAILED -0x6300 |
| #define MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA -0x6100 |
| #define MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE -0x6080 |
| #define MBEDTLS_ERR_CIPHER_FULL_BLOCK_EXPECTED -0x6280 |
| #define MBEDTLS_ERR_CIPHER_INVALID_PADDING -0x6200 |
| #define MBEDTLS_MAX_BLOCK_LENGTH 16 |
| #define MBEDTLS_MAX_IV_LENGTH 16 |
Typedef Documentation
| typedef struct mbedtls_cipher_base_t mbedtls_cipher_base_t |
Enumeration Type Documentation
| anonymous enum |
| enum mbedtls_cipher_id_t |
| enum mbedtls_operation_t |
Function Documentation
| int mbedtls_cipher_crypt | ( | mbedtls_cipher_context_t * | ctx, |
| const unsigned char * | iv, | ||
| size_t | iv_len, | ||
| const unsigned char * | input, | ||
| size_t | ilen, | ||
| unsigned char * | output, | ||
| size_t * | olen | ||
| ) |
Generic all-in-one encryption/decryption (for all ciphers except AEAD constructs).
- Parameters
-
ctx generic cipher context iv IV to use (or NONCE_COUNTER for CTR-mode ciphers) iv_len IV length for ciphers with variable-size IV; discarded by ciphers with fixed-size IV. input buffer holding the input data ilen length of the input data output buffer for the output data. Should be able to hold at least ilen + block_size. Cannot be the same buffer as input! olen length of the output data, will be filled with the actual number of bytes written.
- Note
- Some ciphers don't use IVs nor NONCE. For these ciphers, use iv = NULL and iv_len = 0.
- Returns
- 0 on success, or MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA, or MBEDTLS_ERR_CIPHER_FULL_BLOCK_EXPECTED if decryption expected a full block but was not provided one, or MBEDTLS_ERR_CIPHER_INVALID_PADDING on invalid padding while decrypting, or a cipher specific error code.
| int mbedtls_cipher_finish | ( | mbedtls_cipher_context_t * | ctx, |
| unsigned char * | output, | ||
| size_t * | olen | ||
| ) |
Generic cipher finalisation function.
If data still needs to be flushed from an incomplete block, data contained within it will be padded with the size of the last block, and written to the output buffer.
- Parameters
-
ctx Generic cipher context output buffer to write data to. Needs block_size available. olen length of the data written to the output buffer.
- Returns
- 0 on success, MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA if parameter verification fails, MBEDTLS_ERR_CIPHER_FULL_BLOCK_EXPECTED if decryption expected a full block but was not provided one, MBEDTLS_ERR_CIPHER_INVALID_PADDING on invalid padding while decrypting or a cipher specific error code.
| void mbedtls_cipher_free | ( | mbedtls_cipher_context_t * | ctx | ) |
Free and clear the cipher-specific context of ctx.
Freeing ctx itself remains the responsibility of the caller.
|
inlinestatic |
Returns the block size of the given cipher.
- Parameters
-
ctx cipher's context. Must have been initialised.
- Returns
- size of the cipher's blocks, or 0 if ctx has not been initialised.
Definition at line 329 of file cipher.h.
References mbedtls_cipher_info_t::block_size, and mbedtls_cipher_context_t::cipher_info.
|
inlinestatic |
Returns the mode of operation for the cipher.
(e.g. MBEDTLS_MODE_CBC)
- Parameters
-
ctx cipher's context. Must have been initialised.
- Returns
- mode of operation, or MBEDTLS_MODE_NONE if ctx has not been initialised.
Definition at line 346 of file cipher.h.
References mbedtls_cipher_context_t::cipher_info, MBEDTLS_MODE_NONE, and mbedtls_cipher_info_t::mode.
|
inlinestatic |
Returns the size of the cipher's IV/NONCE in bytes.
- Parameters
-
ctx cipher's context. Must have been initialised.
- Returns
- If IV has not been set yet: (recommended) IV size (0 for ciphers not using IV/NONCE). If IV has already been set: actual size.
Definition at line 363 of file cipher.h.
References mbedtls_cipher_context_t::cipher_info, mbedtls_cipher_info_t::iv_size, and mbedtls_cipher_context_t::iv_size.
|
inlinestatic |
Returns the key length of the cipher.
- Parameters
-
ctx cipher's context. Must have been initialised.
- Returns
- cipher's key length, in bits, or MBEDTLS_KEY_LENGTH_NONE if ctx has not been initialised.
Definition at line 414 of file cipher.h.
References mbedtls_cipher_context_t::cipher_info, mbedtls_cipher_info_t::key_bitlen, and MBEDTLS_KEY_LENGTH_NONE.
|
inlinestatic |
Returns the name of the given cipher, as a string.
- Parameters
-
ctx cipher's context. Must have been initialised.
- Returns
- name of the cipher, or NULL if ctx was not initialised.
Definition at line 397 of file cipher.h.
References mbedtls_cipher_context_t::cipher_info, and mbedtls_cipher_info_t::name.
|
inlinestatic |
Returns the operation of the given cipher.
- Parameters
-
ctx cipher's context. Must have been initialised.
- Returns
- operation (MBEDTLS_ENCRYPT or MBEDTLS_DECRYPT), or MBEDTLS_OPERATION_NONE if ctx has not been initialised.
Definition at line 431 of file cipher.h.
References mbedtls_cipher_context_t::cipher_info, MBEDTLS_OPERATION_NONE, and mbedtls_cipher_context_t::operation.
|
inlinestatic |
Returns the type of the given cipher.
- Parameters
-
ctx cipher's context. Must have been initialised.
- Returns
- type of the cipher, or MBEDTLS_CIPHER_NONE if ctx has not been initialised.
Definition at line 382 of file cipher.h.
References mbedtls_cipher_context_t::cipher_info, MBEDTLS_CIPHER_NONE, and mbedtls_cipher_info_t::type.
| const mbedtls_cipher_info_t* mbedtls_cipher_info_from_string | ( | const char * | cipher_name | ) |
Returns the cipher information structure associated with the given cipher name.
- Parameters
-
cipher_name Name of the cipher to search for.
- Returns
- the cipher information structure associated with the given cipher_name, or NULL if not found.
| const mbedtls_cipher_info_t* mbedtls_cipher_info_from_type | ( | const mbedtls_cipher_type_t | cipher_type | ) |
Returns the cipher information structure associated with the given cipher type.
- Parameters
-
cipher_type Type of the cipher to search for.
- Returns
- the cipher information structure associated with the given cipher_type, or NULL if not found.
| const mbedtls_cipher_info_t* mbedtls_cipher_info_from_values | ( | const mbedtls_cipher_id_t | cipher_id, |
| int | key_bitlen, | ||
| const mbedtls_cipher_mode_t | mode | ||
| ) |
Returns the cipher information structure associated with the given cipher id, key size and mode.
- Parameters
-
cipher_id Id of the cipher to search for (e.g. MBEDTLS_CIPHER_ID_AES) key_bitlen Length of the key in bits mode Cipher mode (e.g. MBEDTLS_MODE_CBC)
- Returns
- the cipher information structure associated with the given cipher_type, or NULL if not found.
| void mbedtls_cipher_init | ( | mbedtls_cipher_context_t * | ctx | ) |
Initialize a cipher_context (as NONE)
| const int* mbedtls_cipher_list | ( | void | ) |
Returns the list of ciphers supported by the generic cipher module.
- Returns
- a statically allocated array of ciphers, the last entry is 0.
| int mbedtls_cipher_reset | ( | mbedtls_cipher_context_t * | ctx | ) |
Finish preparation of the given context.
- Parameters
-
ctx generic cipher context
- Returns
- 0 on success, MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA if parameter verification fails.
| int mbedtls_cipher_set_iv | ( | mbedtls_cipher_context_t * | ctx, |
| const unsigned char * | iv, | ||
| size_t | iv_len | ||
| ) |
Set the initialization vector (IV) or nonce.
- Parameters
-
ctx generic cipher context iv IV to use (or NONCE_COUNTER for CTR-mode ciphers) iv_len IV length for ciphers with variable-size IV; discarded by ciphers with fixed-size IV.
- Returns
- 0 on success, or MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA
- Note
- Some ciphers don't use IVs nor NONCE. For these ciphers, this function has no effect.
| int mbedtls_cipher_setkey | ( | mbedtls_cipher_context_t * | ctx, |
| const unsigned char * | key, | ||
| int | key_bitlen, | ||
| const mbedtls_operation_t | operation | ||
| ) |
Set the key to use with the given context.
- Parameters
-
ctx generic cipher context. May not be NULL. Must have been initialised using cipher_context_from_type or cipher_context_from_string. key The key to use. key_bitlen key length to use, in bits. operation Operation that the key will be used for, either MBEDTLS_ENCRYPT or MBEDTLS_DECRYPT.
- Returns
- 0 on success, MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA if parameter verification fails or a cipher specific error code.
| int mbedtls_cipher_setup | ( | mbedtls_cipher_context_t * | ctx, |
| const mbedtls_cipher_info_t * | cipher_info | ||
| ) |
Initialises and fills the cipher context structure with the appropriate values.
- Note
- Currently also clears structure. In future versions you will be required to call mbedtls_cipher_init() on the structure first.
- Parameters
-
ctx context to initialise. May not be NULL. cipher_info cipher to use.
- Returns
- 0 on success, MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA on parameter failure, MBEDTLS_ERR_CIPHER_ALLOC_FAILED if allocation of the cipher-specific context failed.
| int mbedtls_cipher_update | ( | mbedtls_cipher_context_t * | ctx, |
| const unsigned char * | input, | ||
| size_t | ilen, | ||
| unsigned char * | output, | ||
| size_t * | olen | ||
| ) |
Generic cipher update function.
Encrypts/decrypts using the given cipher context. Writes as many block size'd blocks of data as possible to output. Any data that cannot be written immediately will either be added to the next block, or flushed when cipher_final is called. Exception: for MBEDTLS_MODE_ECB, expects single block in size (e.g. 16 bytes for AES)
- Parameters
-
ctx generic cipher context input buffer holding the input data ilen length of the input data output buffer for the output data. Should be able to hold at least ilen + block_size. Cannot be the same buffer as input! olen length of the output data, will be filled with the actual number of bytes written.
- Returns
- 0 on success, MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA if parameter verification fails, MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE on an unsupported mode for a cipher or a cipher specific error code.
- Note
- If the underlying cipher is GCM, all calls to this function, except the last one before mbedtls_cipher_finish(), must have ilen a multiple of the block size.
