Manual Pages  — SAFE

Alternatively, to load the driver as a module at boot time, place the following line in loader.conf(5):

safe_load="YES"

In sysctl.conf(5): hw.safe.debug hw.safe.dump hw.safe.rnginterval hw.safe.rngbufsize hw.safe.rngmaxalarm

The safe driver registers itself to accelerate AES, SHA1-HMAC, and NULL operations for ipsec(4) and crypto(4).

On all models, the driver registers itself to provide random data to the random(4) subsystem. Periodically the driver will poll the hardware RNG and retrieve data for use by the system. If the driver detects that the hardware RNG is resonating with any local signal, it will reset the oscillators that generate random data. Three sysctl(8) settings control this procedure: hw.safe.rnginterval specifies the time, in seconds, between polling operations, hw.safe.rngbufsize specifies the number of 32-bit words to retrieve on each poll, and hw.safe.rngmaxalarm specifies the threshold for resetting the oscillators.

When the driver is compiled with SAFE_DEBUG defined, two sysctl(8) variables are provided for debugging purposes: hw.safe.debug can be set to a non-zero value to enable debugging messages to be sent to the console for each cryptographic operation, hw.safe.dump is a write-only variable that can be used to force driver state to be sent to the console. Set this variable to "ring" to dump the current state of the descriptor ring, to "dma" to dump the hardware DMA registers, or to "int" to dump the hardware interrupt registers.