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CRYPTO(4) Device Drivers Manual CRYPTO(4)


crypto, cryptodev
hardware crypto access driver


device crypto
device cryptodev


The crypto driver provides a device-independent framework to support cryptographic operations in the kernel. The cryptodev driver provides userland applications access to this support through the /dev/crypto device. This node primarily operates in an ioctl(2) based model, permitting a variety of applications to query device capabilities, submit transactions, and get results.
If count given in the specification, and is greater than 0, a maximum of one crypto device is created.
The following ioctl(2) calls apply only to the crypto devices:
Setup a new crypto session for a new type of operation.
Free a previously established session.
Perform a crypto operation against a previously setup session.


Depending on hardware being present, the following symmetric and asymmetric cryptographic features are potentially available from /dev/crypto:


crypto access device


aesni(4), glxsb(4), hifn(4), ipsec(4), padlock(4), safe(4), ubsec(4), geli(8), crypto(9)


The crypto driver first appeared in OpenBSD 3.0. The crypto driver was imported to FreeBSD 5.0.
September 7, 2010 Debian