NAME
tap - virtual Ethernet device
SYNOPSIS
pseudo-device tap
DESCRIPTION
The tap driver allows the creation and use of virtual Ethernet devices.
Those interfaces appear just as any real Ethernet NIC to the kernel, but
can also be accessed by userland through a character device node in order
to read frames being sent by the system or to inject frames.
In that respect it is very similar to what tun(4) provides, but the added
Ethernet layer allows easy integration with machine emulators or virtual
Ethernet networks through the use of bridge(4) with tunneling.
``Qui tacet consentire videtur.''
clients, and a pseudo-device for userspace access.
The attribute is named `opencrypto'. The pseudo-device is renamed to
"crypto", which has a dependency on "opencrypto". The sys/conf/majors
entry and pseudo-device attach entrypoint are updated to match the
new pseudo-device name.
Fast IPsec (sys/netipsec/files.ipsec) now lists a dependency on the
"opencrypto" attribute. Drivers for crypto accelerators (ubsec,
hifn775x) also pull in opencrypto, as providers of opencrypto transforms.
Uses a hook in spec_strategy() to save data written from a mounted
file system to its block device and a hook in dounmount().
Not enabled by default in any kernel config.
Approved by: Frank van der Linden <fvdl@netbsd.org>