1KCAPI_AKCIPHER_DECRY(3) Programming Interface KCAPI_AKCIPHER_DECRY(3)
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6 kcapi_akcipher_decrypt - decrypt data
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9 int32_t kcapi_akcipher_decrypt(struct kcapi_handle * handle,
10 const uint8_t * in, uint32_t inlen,
11 uint8_t * out, uint32_t outlen,
12 int access);
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15 handle
16 [in] cipher handle
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18 in
19 [in] ciphertext data buffer
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21 inlen
22 [in] length of in buffer
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24 out
25 [out] plaintext data buffer
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27 outlen
28 [in] length of out buffer
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30 access
31 [in] kernel access type (KCAPI_ACCESS_HEURISTIC - use internal
32 heuristic for fastest kernel access; KCAPI_ACCESS_VMSPLICE - use
33 vmsplice access; KCAPI_ACCESS_SENDMSG - sendmsg access)
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36 It is perfectly legal to use the same buffer as the plaintext and
37 ciphertext pointers. That would mean that after the decryption
38 operation, the ciphertext is overwritten with the plaintext.
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40 The memory should be aligned at the page boundary using
41 posix_memalign(sysconf(_SC_PAGESIZE)), If it is not aligned at the page
42 boundary, the vmsplice call may not send all data to the kernel.
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44 If the output size is insufficiently large, -EINVAL is returned. The
45 output buffer must be at least as large as the modululs of the uses
46 key.
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48 return number of bytes returned by the decryption operation upon
49 success; a negative errno-style error code if an error occurred
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52 Stephan Mueller <smueller@chronox.de>
53 Author.
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56libkcapi Manual 1.2.1 March 2021 KCAPI_AKCIPHER_DECRY(3)