Wireshark · Wireshark-dev: Re: [Wireshark-dev] How Wireshark supports monitor mode for WLAN 802.11 adapter in Windows?

[Guy Harris <guy@xxxxxxxxxxxx>]

By the way, the next thing you'll have to do, if you haven't done so already, is to handle raw 802.11 packet indications from NDIS:

	https://msdn.microsoft.com/EN-US/library/ff554833.aspx

which seems to imply that you need to set NDIS_PACKET_TYPE_802_11_RAW_DATA and NDIS_PACKET_TYPE_802_11_RAW_MGMT in the packet filter.

And if you want to supply radio information for received packets, there's more work to do.  That information is provided as "Media-Specific OOB Data for Received 802.11 Packets":

	https://msdn.microsoft.com/en-us/library/windows/hardware/ff559169(v=vs.85).aspx

in a DOT11_EXTSTA_RECV_CONTEXT structure:

	https://msdn.microsoft.com/en-us/library/windows/hardware/ff548626(v=vs.85).aspx

To do this, you'd provide a link-layer header type of DLT_IEEE802_11_RADIO, and synthesize a radiotap header.  When you open the device, you'd have to fetch the device's data rate mapping table with the OID_DOT11_DATA_RATE_MAPPING_TABLE OID:

	https://msdn.microsoft.com/en-us/library/windows/hardware/ff569139(v=vs.85).aspx

	https://msdn.microsoft.com/en-us/library/windows/hardware/ff547679(v=vs.85).aspx

and associate that with the private data for the pcap_t.

Then, for each received packet:

    if DOT11_RECV_FLAG_RAW_PACKET_TIMESTAMP is set in uReceiveFlags, provide a TSFT field with the value from the ullTimestamp field of the structure;

    provide a Flags field with 0x10 set if the frame includes the FCS (you'll probably have to experiment a bit to see whether you get the FCS or not - the answer might differ for data and management frames, based on Network Monitor's behavior) and with 0x40 set if DOT11_RECV_FLAG_RAW_PACKET_FCS_FAILURE is set in uReceiveFlags;

    provide a Rate field whose value is the result of looking up the ucDataRate field's value in the data rate mapping table and returning the usDataRateValue value from that table - if it's not found, don't provide the Rate field;

    provide a Channel field where the frequency value is the uChCenterFrequency field of the structure and the flags are derived from the uChCenterFrequency and uPhyId fields of the structure - assuming that the uPhyId value is one of the ones from

	https://msdn.microsoft.com/en-us/library/windows/hardware/ff548741(v=vs.85).aspx

    then the mapping would be:

	dot11_phy_type_fhss - set 0x0800 in the flags (11 legacy FHSS);

	dot11_phy_type_ofdm - set 0x0040 in the flags (11a);

	dot11_phy_type_hrdsss - set 0x0020 in the flags (11b);

	dot11_phy_type_erp - set 0x0040 in the flags (11g, unknown whether it's pure or not);

    and, unless it's dot11_phy_type_irbaseband, set 0x0100 if the frequency is in the 5 GHz range or set 0x0080 if it's in the 2.4 GHz range;

    provide a Antenna signal field whose value is the value of the lRSSI field in the structure;

    if the phy is dot11_phy_type_ht, provide an MCS field where the known field is 0 and the other fields are also zeroed out (i.e., it's 11n, but we don't know anything else about it);

    if the phy is dot11_phy_type_vht, provide an VHT field where the known field is 0 and the other fields are also zeroed out (i.e., it's 11ac, but we don't know anything else about it).