Provided the SCX-3400 can be networked, whether wired or wireless, Apple's built-in AirPrint supports the following devices and they might coincidentally support the SCX-3400:
Samsung SCX-3405FW
Samsung SCX-3405HW
Samsung SCX-3405W
Samsung SCX-3406FW
Samsung SCX-3406HW
Samsung SCX-3406W
Samsung SCX-3407W
If AirPrint does support the SCX-3400, then you will not need any Samsung drivers for the device.
For AirPrint configuration after networking the device (without any USB cables attached) and with power, visit System Settings > Printers & Scanners panel. If the SCX-3400 appears in the Printers listing, right-click on that entry, select Reset the Printing System… and acknowledge on the subsequent dialog. That will remove the device entry. Click Add Printer, Scanner, or Fax… button.
An Add Printer panel will appear with Default selected and (hopefully) a Bonjour entry with your SCX-3400 detected in the Name field. Click that entry and again (hopefully), the Use selector will autoselect some 3400-series AirPrint driver for you. Then click Add to reinstate your device in the Printers listing.
This is how that Add panel behaves when I reset and re-add AirPrint support for my Samsung ML-2955ND laser:
