NAME

       kcapi_akcipher_decrypt - decrypt data

SYNOPSIS

       int32_t kcapi_akcipher_decrypt(struct kcapi_handle * handle, const uint8_t * in,
                                      uint32_t inlen, uint8_t * out, uint32_t outlen,
                                      int access);

ARGUMENTS

       handle
           [in] cipher handle

       in
           [in] ciphertext data buffer

       inlen
           [in] length of in buffer

       out
           [out] plaintext data buffer

       outlen
           [in] length of out buffer

       access
           [in] kernel access type (KCAPI_ACCESS_HEURISTIC - use internal heuristic for fastest
           kernel access; KCAPI_ACCESS_VMSPLICE - use vmsplice access; KCAPI_ACCESS_SENDMSG -
           sendmsg access)

DESCRIPTION

       It is perfectly legal to use the same buffer as the plaintext and ciphertext pointers.
       That would mean that after the decryption operation, the ciphertext is overwritten with
       the plaintext.

       The memory should be aligned at the page boundary using
       posix_memalign(sysconf(_SC_PAGESIZE)), If it is not aligned at the page boundary, the
       vmsplice call may not send all data to the kernel.

       If the output size is insufficiently large, -EINVAL is returned. The output buffer must be
       at least as large as the modululs of the uses key.

       return number of bytes returned by the decryption operation upon success; a negative
       errno-style error code if an error occurred

AUTHOR

       Stephan Mueller <smueller@chronox.de>
           Author.

COPYRIGHT