airmon-ng.linux: use default channels supported by hardware

scripts/airmon-ng.linux

@@ -59,10 +59,10 @@ if [ -n "${3}" ];then
 		CH="${3}"
 	else
 		printf "\nYou have entered an invalid channel or frequency \"%s\" which will be ignored\n" "${3}"
-		CH="default"
+		CH="0"
 	fi
 else
-	CH="default"
+	CH="0"
 fi
 
 #TODO LIST
@@ -636,50 +636,53 @@ startwlIface() {
 setChannelMac80211() {
   setLink "${1}" up
   i=0
-  if [ "${CH}" = "default" ]; then
-    if [ "${DRIVER}" = "wil6210" ]; then
-      #wil6210 doesn't support setting by channel afaict, so set band 3 / 60GHz channel 1 by freq
-      CH="58320"
-    else
-      # everyone else defaults to channel 1
-      CH="1"
-    fi
-  elif [ "${DRIVER}" = "wil6210" ] && [ "${CH}" -lt "58320" ]; then
-    printf "wil6210 doesn't support setting by channel, please specify a frequency\n"
-    exit 1
-  fi
-
   if [ -n "${CH}" ]; then
-    if [ "${CH}" -lt 900 ]; then
+    # if channel is less than 900 assume it's a channel and try to set it as a channel
+    # wil6210 driver doesn't support setting by channel afaict so jump it to the else
+    if [ "${CH}" -lt 900 ] && [ "${DRIVER}" != "wil6210" ]; then
       if [ -r "/sys/class/net/$1/phy80211/name" ]; then
         channel_list="$(iw phy "$(cat "/sys/class/net/${1}/phy80211/name")" channels 2>&1 | awk -F'[][]' '$2{print $2}')"
         hardware_valid_channel=1
         for i in $channel_list; do
+          if [ "${CH}" = "0" ]; then
+            # channel 0 means default, default means set first supported channel
+            CH="${i}"
+            hardware_valid_channel=0
+            break
+          fi
           if [ "${CH}" = "${i}" ]; then
             hardware_valid_channel=0
             break
           fi
+          last_chan="${i}"
         done
         if [ "${hardware_valid_channel}" = "1" ]; then
-          printf "Channel %s does not appear to be supported by %s hardware, defaulting to channel 3.\n\n" "${CH}" "${1}"
-          CH=3
+          printf "Channel %s does not appear to be supported by %s hardware, defaulting to known valid channel %s\n\n" "${CH}" "${1}" "${last_chan}"
+          CH="${last_chan}"
         fi
       fi
       IW_ERROR="$(iw dev "${1}" set channel "${CH}" 2>&1)"
+    # channel is 900 or over, assume it's a frequency and set it as such
     else
       if [ -r "/sys/class/net/$1/phy80211/name" ]; then
         frequency_list="$(iw phy "$(cat "/sys/class/net/${1}/phy80211/name")" channels 2>&1 | sed -nr 's/.*( |^)([0-9]+) MHz .*/\2/p')"
         hardware_valid_freq=1
         for i in $frequency_list; do
+          if [ "${CH}" = "0" ]; then
+            # channel 0 means default, default means set first supported freq
+            CH="${i}"
+            hardware_valid_channel=0
+            break
+          fi
           if [ "${CH}" = "${i}" ]; then
             hardware_valid_freq=0
             break
           fi
-          print
+          last_freq="${i}"
         done
         if [ "${hardware_valid_freq}" = "1" ]; then
-          printf "Frequency %s does not appear to be supported by %s hardware, defaulting to 2422 Mhz.\n\n" "${CH}" "${1}"
-          CH="2422"
+          printf "Frequency %s does not appear to be supported by %s hardware, defaulting to known valid freq %s Mhz\n\n" "${CH}" "${1}" "${last_freq}"
+          CH="${last_freq}"
         fi
       fi
       IW_ERROR="$(iw dev "${1}" set freq "${CH}" 2>&1)"