1KCAPI_AKCIPHER_SIGN(3) Programming Interface KCAPI_AKCIPHER_SIGN(3)
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6 kcapi_akcipher_sign - signature generation
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9 int32_t kcapi_akcipher_sign(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] message data buffer
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21 inlen
22 [in] length of in buffer
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24 out
25 [out] signature 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 message and
37 signature pointers. That would mean that after the signature generation
38 operation, the message is overwritten with the signature.
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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 signature gen 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_SIGN(3)