NAME

       crda - send to the kernel a wireless regulatory domain for a given ISO / IEC 3166 alpha2

SYNOPSIS

       crda

Description

       crda is the Linux wireless central regulatory domain agent.  crda is intended to be used by udev scripts
       and should not be run manually unless debugging udev scripts.  crda is triggered to run by the kernel by
       sending a udev event upon a new regulatory domain change. Regulatory domain changes are triggered by the
       wireless kernel subsystem (upon initialization and on reception of country IEs), wireless drivers, or
       userspace (see iw ). Upon a regulatory domain change the kernel sends a udev change event for the
       regulatory platform. The kernel ignores regulatory domains sent to it if it does not expect them. The
       regulatory domain is read by crda from the regulatory.bin file.

RSA Digital Signature

       If built with openssl or gcrypt support crda will have embedded into it an RSA digital signature which
       will prevent it from reading corrupted or non-authored regulatory.bin files. Authorship is respected by
       the RSA public key packed into crda.  This specific crda package has been built with RSA public keys from
       John Linville (the Linux wireless kernel maintainer) and Seth Forshee (the wireless regulatory databse
       maintainer) and as such will only read regulatory.bin files signed by one of them. For further
       information see the regulatory.bin man page.

UDEV RULE

       A udev regulatory rule must be put in place in order to receive and parse udev events from the kernel in
       order to get udev to call crda with the passed ISO / IEC 3166 alpha2 country code.  An example udev rule
       which can be used (usually in /lib/udev/rules.d/85-regulatory.rules ):

       KERNEL=="regulatory*", ACTION=="change", SUBSYSTEM=="platform", RUN+="/sbin/crda"

Environment variable

       Set the COUNTRY environment variable with a specific ISO / IEC 3166 alpha2 country code and then run crda
       without arguments. This will send a regulatory domain for that alpha2 to the kernel.

SEE ALSO

       iw(8) regulatory.bin(5)

       http://wireless.kernel.org/en/developers/Regulatory/

crda                                             23 January 2009                                         CRDA(8)