---
name: "fido"
section: "4"
platform: "openbsd"
package: "man"
version: "8.0-current-20261101"
release: "OpenBSD 8.0-current (2026-11-01)"
platforms: ["openbsd"]
url: "https://new.carta.tech/fido"
---

# fido(4)

FIDO/U2F security keys

## NAME

**fido** – FIDO/U2F security keys

## SYNOPSIS

**fido\* at uhidev?**

## DESCRIPTION

The **fido** driver provides support for FIDO/U2F-compatible USB security keys. They are Human Interface Devices (HID) which can be accessed via the */dev/fido/N* interface.

The driver is compatible with the [read(2)](/read/2.md), [write(2)](/write/2.md), and [ioctl(2)](/ioctl/2.md) operations of the generic [uhid(4)](/uhid/4.md) device but only accepts the optional HID [ioctl(2)](/ioctl/2.md) calls from root.

## FILES

- */dev/fido/\**

  ## SEE ALSO

[uhid(4)](/uhid/4.md), [uhidev(4)](/uhidev/4.md), [usb(4)](/usb/4.md)

## HISTORY

The **fido** driver first appeared in OpenBSD 6.7.