KS_HMAC_SALT_OFFSET
#define KS_HASHED_PIN_SALT_LEN_OFFSET (KS_HMAC_SALT_OFFSET + KS_HMAC_SALT_SIZE)
if (lseek(fd, KS_HMAC_SALT_OFFSET, SEEK_SET) != KS_HMAC_SALT_OFFSET) {