Re: [clearview-discuss] libdlpi with libpcap

[Peter Memishian <peter.memishian () Sun COM>]

> With an 802.11 device, does turning DLPI_NATIVE on put the device into  
> monitor mode, or does it just cause it to supply 802.11 headers?

It just causes it to supply 802.11 headers.  We may later add support to
monitor.

> Is there a way to query whether a device supports DLPI_NATIVE  
> ("supports" in the sense that it gives different link-layer headers  
> depending on whether it's set or not)?

The ioctl libdlpi uses (see below) will fail if native mode is not
supported on that link.  But in general, we expect monitoring apps will
just always request native mode and will want to continue on if the
underlying driver doesn't support it.

> Is there a raw DLPI (without libdlpi) equivalent to DLPI_NATIVE in pre- 
> Solaris 11 releases?

Support for native only exists in Solaris 11, but there is a DLPI
equivalent, covered in dlpi(7P):

     Native Mode

         Some DLPI providers may be able to represent their  link
         layer  using  more  than one link-layer  format. In this
         case, the  default link-layer format may minimize impact
         to  applications, but may not allow truly "native" link-
         layer headers to be sent or received. DLPI consumers who
         wish to use the native  link-layer format can use DLIOC-
         NATIVE to transition the stream.  DLIOCNATIVE  takes  no
         arguments  and returns the DLPI mac type associated with
         the  new link-layer format   upon         success.  Once
         enabled,  the  stream remains in this mode until closed.
         Note  that   DLIOCNATIVE  does  not  enable   transition
         between  dissimilar  DLPI  mac types and (aside from the
         link-layer  format),  the  new  DLPI    mac    type   is
         guaranteed  to be semantically identical. In particular,
         the SAP space and addressing format are not affected and
         the  effect  of  DLIOCNATIVE is only visible when in raw
         mode, though any subsequent DL_INFO_REQ   requests  gen-
         erate  responses with dl_mac_type set to the native DLPI
         type.

> And, speaking of monitor mode, is there a way to put an 802.11 adapter  
> into monitor mode, and is there a way to set the channel it uses?   

AFAIK, there's no way to do that at this time -- most of the control
messages never make it beyond the net80211 kernel module.  It's
probably worth verifying my understanding via the laptop-discuss
alias though, as that is monitored by the WiFi team.

-- 
meem
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