smb_crc_gen
extern uint32_t smb_crc_gen(uint8_t *, size_t);
ioc->crc = smb_crc_gen((uint8_t *)ioc, sizeof (smb_ioc_header_t));
if (smb_crc_gen((uint8_t *)&ioc_hdr, sizeof (ioc_hdr)) != crc)
uint32_t smb_crc_gen(uint8_t *, size_t);