1KCAPI_AEAD_STREAM_IN(3) Programming Interface KCAPI_AEAD_STREAM_IN(3)
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6 kcapi_aead_stream_init_dec - start a decryption operation (stream)
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9 int32_t kcapi_aead_stream_init_dec(struct kcapi_handle * handle,
10 const uint8_t * iv,
11 struct iovec * iov,
12 uint32_t iovlen);
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15 handle
16 [in] cipher handle
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18 iv
19 [in] IV to be used for cipher operation
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21 iov
22 [in] scatter/gather list with data to be encrypted. This is the
23 pointer to the first iov entry if an array of iov entries is
24 supplied. See sendmsg(2) for details on how iov is to be used. This
25 pointer may be NULL if no data to be encrypted is available at the
26 point of the call.
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28 iovlen
29 [in] number of scatter/gather list elements. If iov is NULL, this
30 value must be zero.
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33 A stream decryption operation is started with this call. Multiple
34 successive kcapi_aead_stream_update function calls can be invoked to
35 send more ciphertext data to be encrypted. The kernel buffers the input
36 until kcapi_aead_stream_op picks up the decrypted data. Once ciphertext
37 is decrypted during the kcapi_aead_stream_op it is removed from the
38 kernel buffer.
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40 Note, unlike the corresponding symmetric cipher API, the function calls
41 of kcapi_aead_stream_update and kcapi_aead_stream_op cannot be mixed!
42 This due to the nature of AEAD where the cipher operation ensures the
43 integrity of the entire data (decryption) or calculates a message
44 digest over the entire data (encryption).
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46 When using the stream API, the caller must ensure that data is sent in
47 the correct order (regardless whether data is sent in multiple chunks
48 using kcapi_aead_stream_init_enc or kcapi_cipher_stream_update): (i)
49 the complete associated data must be provided, followed by (ii) the
50 plaintext. For decryption, also (iii) the tag value must be sent.
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52 The IV buffer must be exactly kcapi_cipher_ivsize bytes in size.
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54 return number of bytes sent to the kernel upon success; a negative
55 errno-style error code if an error occurred
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58 Stephan Mueller <smueller@chronox.de>
59 Author.
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62libkcapi Manual 1.1.4 February 2019 KCAPI_AEAD_STREAM_IN(3)