1KCAPI_CIPHER_DEC_AES(3)      Programming Interface     KCAPI_CIPHER_DEC_AES(3)
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NAME

6       kcapi_cipher_dec_aes_cbc - Convenience function for AES CBC decryption
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SYNOPSIS

9       ssize_t kcapi_cipher_dec_aes_cbc(const uint8_t * key, uint32_t keylen,
10                                        const uint8_t * in, size_t inlen,
11                                        const uint8_t * iv, uint8_t * out,
12                                        size_t outlen);
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ARGUMENTS

15       key
16           [in] key buffer
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18       keylen
19           [in] length of key buffer
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21       in
22           [in] ciphertext data buffer
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24       inlen
25           [in] length of in buffer
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27       iv
28           [in] IV to be used for cipher operation
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30       out
31           [out] plaintext data buffer
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33       outlen
34           [in] length of out buffer
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DESCRIPTION

37       The convenience function performs an AES CBC decryption operation using
38       the provided key, the given input buffer and the given IV. The output
39       is stored in the out buffer.
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41       Note, AES CBC requires an input data that is a multiple of 16 bytes. If
42       you have data that is not guaranteed to be multiples of 16 bytes,
43       either add zero bytes at the end of the buffer to pad it up to a
44       multiple of 16 bytes. Otherwise, the CTR mode encryption operation may
45       be usable.
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47       The output buffer must be at least as large as the input buffer.
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49       The IV must be exactly 16 bytes in size.
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51       The AES type (AES-128, AES-192 or AES-256) is determined by the size of
52       the given key. If the key is 16 bytes long, AES-128 is used. A 24 byte
53       key implies AES-192 and a 32 byte key implies AES-256.
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55       return number of bytes generated upon success; a negative errno-style
56       error code if an error occurred
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AUTHOR

59       Stephan Mueller <smueller@chronox.de>
60           Author.
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63libkcapi Manual 1.4.0              July 2023           KCAPI_CIPHER_DEC_AES(3)
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