API to construct 802.11 frames in C without managing control fields - c

Question

I am trying to build and send 802.11 frames in C. I saw that it is possible to do it with pcap for instance. However, in all example I saw, I have to set myself sequence number and other control fields. So I'm wondering if there is an API that permits to manage all this control part and where I only have to specify addresses ?
Thank you in advance,

Answer 1

First of all what type of packet are you trying to make? Data frames or beacon frames.....
If you are creating from the scratch you need to set all the parameters yourself, i am using this header file
[ieee80211]http://lxr.free-electrons.com/source/include/linux/ieee80211.h
for the 802.11 configuration parameters, and for radiotap headers , you can use
[radiotap]http://lxr.free-electrons.com/source/include/net/ieee80211_radiotap.h
i can give you an example code(part of) of creating beacon frames
// Add the radiotap header
radiotap->it_version = 0;
radiotap->it_len = sizeof(*radiotap) + sizeof(dataRate);
radiotap->it_present = (1 << IEEE80211_RADIOTAP_RATE);
// Beacon packet flags
dot80211->i_fc[0] = IEEE80211_FC0_VERSION_0 | IEEE80211_FC0_TYPE_MGT | IEEE80211_FC0_SUBTYPE_BEACON;
dot80211->i_fc[1] = IEEE80211_FC1_DIR_NODS;
dot80211->i_dur[0] = 0x0;
dot80211->i_dur[1] = 0x0;
// Destination = broadcast (no retries)
memcpy( dot80211->i_addr1, mac_Destination, IEEE80211_ADDR_LEN );
// Source = our own mac address
memcpy( dot80211->i_addr2, mac_source, IEEE80211_ADDR_LEN );
// BSS = our mac address
memcpy( dot80211->i_addr3, mac_BSSID, IEEE80211_ADDR_LEN );
// Sequence control: Automatically set by the driver
beacon -> beacon_timestamp = TimeStamp;
printf("%"PRIu64,beacon -> beacon_timestamp);
// interval = 100 "time units" = 102.4 ms
// Each time unit is equal to 1024 us
beacon->beacon_interval = BEACON_INTERVAL;
// capabilities = sent by ESS
//beacon->beacon_capabilities = x0003;
For Example :
dot80211->i_fc[0] = IEEE80211_FC0_VERSION_0 | IEEE80211_FC0_TYPE_MGT | IEEE80211_FC0_SUBTYPE_BEACON;
You can the set the FCS(frame control) like this, which is defined in the header.
My suggestion is to create your own header files or modify it according to your need..
Hope this helps ??