kcapi_cipher_decrypt - decrypt data (synchronous one shot)

handle
           [in] cipher handle

       in
           [in] ciphertext data buffer

       inlen
           [in] length of in buffer

       iv
           [in] IV to be used for cipher operation

       out
           [out] plaintext data buffer

       outlen
           [in] length of out bufferS

       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)

StephanMueller <smueller@chronox.de>
           Author.

libkcapi Manual 1.5.0                              April 2024                            KCAPI_CIPHER_DECRYPT(3)

       It is perfectly legal to use the same buffer as the plaintext and ciphertext pointers. That would mean
       that after the encryption 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.

       The IV buffer must be exactly kcapi_cipher_ivsize bytes in size.

       return number of bytes decrypted upon success; a negative errno-style error code if an error occurred

       kcapi_cipher_decrypt - decrypt data (synchronous one shot)

ssize_tkcapi_cipher_decrypt(structkcapi_handle*handle,constuint8_t*in,size_tinlen,constuint8_t*iv,uint8_t*out,size_toutlen,intaccess);