version 0.7.1

This reverts commit 73441c4ed3.

README.md

@@ -4,7 +4,8 @@ Set Linux as router in one command. Able to provide Internet, or create WiFi hot
 
 It wraps `iptables`, `dnsmasq` etc. stuff. Use in one command, restore in one command or by `control-c` (or even by closing terminal window).
 
-[More tools and projects 🛠️](https://garywill.github.io) | [🍻 Buy me a coffee ❤️](https://github.com/garywill/receiving/blob/master/receiving_methods.md)
+[Linux-Router News & Developer Notes 📰](https://github.com/garywill/linux-router/issues/28) | [More tools and projects 🛠️](https://garywill.github.io) | [🍻 Buy me a coffee ❤️](https://github.com/garywill/receiving/blob/master/receiving_methods.md)
+
 
 ## Features
 
@@ -23,7 +24,7 @@ Basic features:
   - Create AP on the same interface you are getting Internet (usually require same channel)
 - Transparent proxy (redsocks)
 - Transparent DNS proxy (hijack port 53 packets)
-- Compatible with NetworkManager (automatically set interface as unmanaged)
+- Detect NetworkManager and make sure it won't interfere (handle interface (un)managed status)
 - You can run many instances, to create many different networks. Has instances managing feature.
 
 **For many other features, see below [CLI usage](#cli-usage-and-other-features)**
@@ -61,6 +62,31 @@ Internet----(eth0/wlan0)-Linux-(eth1)------Another PC
 Internet----(eth0/wlan0)-Linux-(virtual interface)-----VM/container
 ```
 
+## Install
+
+1-file-script. Release on [Linux-router repo on Github](https://github.com/garywill/linux-router). Just download and run the bash script (meet the dependencies). In this case use without installation.
+
+> I'm currently not packaging for any distro. If you do, open a PR and add the link (can be with a version badge) to list here
+
+| Linux distro |                                                                                                            |
+| ------------ | ---------------------------------------------------------------------------------------------------------- |
+| Any          | download [1-file-script](https://raw.githubusercontent.com/garywill/linux-router/master/lnxrouter) and run without installation |
+
+### Dependencies
+
+- bash
+- procps or procps-ng
+- iproute2
+- dnsmasq
+- iptables (or nftables with `iptables-nft` translation linked)
+- WiFi hotspot dependencies
+  - hostapd
+  - iw
+  - iwconfig (you only need this if 'iw' can not recognize your adapter)
+  - haveged (optional)
+
+
+
 ## Usage
 
 ### Provide Internet to an interface
@@ -92,13 +118,13 @@ sudo lnxrouter -i eth1 -o isp5  --no-dns  --dhcp-dns 1.1.1.1  -6 --dhcp-dns6 [26
 > In this case of usage, it's recommended to:
 > 
 > 1. Stop serving local DNS
-> 2. Tell clients which DNS to use (ISP5's DNS. Or, a safe public DNS, like above example)
+> 2. Tell clients which DNS to use ISP5's DNS. (Or, a safe public DNS, like above example)
 
 > Also, read *Notice 1*
 
 </details>
 
-### LAN without Internet
+### Create LAN without providing Internet
 
 <details>
 
@@ -138,7 +164,7 @@ sudo lnxrouter -i lxcbr5
 
 ### Transparent proxy
 
-All clients' Internet traffic go through, for example, Tor
+All clients' Internet traffic go through, for example, Tor (notice this example is NOT an anonymity use)
 
 <details>
 
@@ -155,6 +181,10 @@ TransPort [fd00:5:6:7::1]:9040
 DNSPort [fd00:5:6:7::1]:9053
 ```
 
+> **Warn**: Tor's anonymity relies on a purpose-made browser. Using Tor like this (sharing Tor's network to LAN clients) will NOT ensure anonymity.
+> 
+> Although we use Tor as example here, Linux-router does NOT ensure nor is NOT aiming at anonymity.
+
 </details>
 
 ### Clients-in-sandbox network
@@ -173,7 +203,7 @@ sudo lnxrouter -i eth1 \
 
 </details>
 
-> This script comes with no warrenty. Use on your own risk
+> Linux-router comes with no warranty. Use on your own risk
 
 ### Use as transparent proxy for LXD
 
@@ -317,26 +347,28 @@ Options:
     -d                      DNS server will take into account /etc/hosts
     -e <hosts_file>         DNS server will take into account additional 
                             hosts file
+    --dns-nocache           DNS server no cache
     
     --mac <MAC>             Set MAC address
     --random-mac            Use random MAC address
  
     --tp <port>             Transparent proxy,
-                            redirect non-LAN TCP and UDP traffic to port.
+                            redirect non-LAN TCP and UDP(not tested) traffic to
-                            (usually used with '--dns')
+                            port. (usually used with '--dns')
     
   WiFi hotspot options:
     --ap <wifi interface> <SSID>
                             Create WiFi access point
     -p, --password <password>   
                             WiFi password
-    --qr                    Show WiFi QR code in terminal
+    --qr                    Show WiFi QR code in terminal (need qrencode)
     
     --hidden                Hide access point (not broadcast SSID)
     --no-virt               Do not create virtual interface
                             Using this you can't use same wlan interface
                             for both Internet and AP
-    -c <channel>            Channel number (default: 1)
+    --virt-name <name>      Set name of virtual interface
+    -c <channel>            Specify channel (default: use current, or 1 / 36)
     --country <code>        Set two-letter country code for regularity
                             (example: US)
     --freq-band <GHz>       Set frequency band: 2.4 or 5 (default: 2.4)
@@ -350,13 +382,28 @@ Options:
                             (defaults to /etc/hostapd/hostapd.accept)
     --hostapd-debug <level> 1 or 2. Passes -d or -dd to hostapd
     --isolate-clients       Disable wifi communication between clients
-
-    --ieee80211n            Enable IEEE 802.11n (HT)
-    --ieee80211ac           Enable IEEE 802.11ac (VHT)
-    --ht_capab <HT>         HT capabilities (default: [HT40+])
-    --vht_capab <VHT>       VHT capabilities
-
     --no-haveged            Do not run haveged automatically when needed
+    --hs20                  Enable Hotspot 2.0
+
+    WiFi 4 (802.11n) configs:
+    --wifi4                 Enable IEEE 802.11n (HT)
+    --req-ht                Require station HT (High Throughput) mode
+    --ht-capab <HT caps>    HT capabilities (default: [HT40+])
+
+    WiFi 5 (802.11ac) configs:
+    --wifi5                 Enable IEEE 802.11ac (VHT)
+    --req-vht               Require station VHT (Very High Thoughtput) mode
+    --vht-capab <VHT caps>  VHT capabilities
+    
+    --vht-ch-width <index>  Index of VHT channel width:
+                                0 for 20MHz or 40MHz (default)
+                                1 for 80MHz
+                                2 for 160MHz
+                                3 for 80+80MHz (Non-contigous 160MHz)    
+    --vht-seg0-ch <channel> Channel index of VHT center frequency for primary 
+                            segment. Use with '--vht-ch-width'
+    --vht-seg1-ch <channel> Channel index of VHT center frequency for secondary
+                            (second 80MHz) segment. Use with '--vht-ch-width 3'
 
   Instance managing:
     --daemon                Run in background
@@ -368,10 +415,43 @@ Options:
     --stop <id>             Stop a running instance
         For <id> you can use PID or subnet interface name.
         You can get them with '--list-running'
+
+    Notice 1:   This script assume your host's default policy won't forward
+                packets, so the script won't explictly ban forwarding in any
+                mode. In some unexpected case (eg. mistaken configurations) may
+                cause unwanted packets leakage between 2 networks, which you
+                should be aware of if you want isolated network
 ```
 
 </details>
 
+## What changes are done to Linux system
+
+On exit of a linux-router instance, script **will do cleanup**, i.e. undo most changes to system. Though, **some** changes (if needed) will **not** be undone, which are:
+
+1. `/proc/sys/net/ipv4/ip_forward = 1` and `/proc/sys/net/ipv6/conf/all/forwarding = 1`
+2. dnsmasq in Apparmor complain mode
+3. hostapd in Apparmor complain mode
+4. Kernel module `nf_nat_pptp` loaded
+5. The wifi device which is used to create hotspot is `rfkill unblock`ed
+6. WiFi country code, if user assigns
+
+## Meet contributor(s) and become one of them
+
+Visit [**my homepage** 🏡](https://garywill.github.io) to see **more tools and projects** 🛠️.
+
+> [❤️ Buy me a coffee](https://github.com/garywill/receiving/blob/master/receiving_methods.md) , this project took me lots of time! ([❤️ 扫码领红包并打赏一个!](https://github.com/garywill/receiving/blob/master/receiving_methods.md))
+> 
+> 🥂 ( ^\_^) o自自o (^_^ ) 🍻
+
+🤝 Bisides, thank [create_ap](https://github.com/oblique/create_ap) by [oblique](https://github.com/oblique). This script was forked from create\_ap. Now they are quite different. (See `history` branch for how I modified create_ap). 🤝 Also thank those who contributed to that project.
+
+👨‍💻 You can be contributor, too! 
+
+- 🍃 There're some TO-DOs listed, in both [readme TODO](#todo) and [in the code file](https://github.com/garywill/linux-router/search?q=TODO&type=code)
+- 🍃 Also some [unfulfilled enhancements in the Issues](https://github.com/garywill/linux-router/issues?q=is%3Aissue+is%3Aopen+label%3Aenhancement)
+- 🙋‍♂️ Contributions are not limited to coding. There're [some posts and questions](https://github.com/garywill/linux-router/issues) that need more people to answer
+
 ## Notice
 
 <details>
@@ -386,43 +466,17 @@ Options:
 
 </details>
 
-## What changes are done to Linux system
-
-On exit of a linux-router instance, script **will do cleanup**, i.e. undo most changes to system. Though, **some** changes will **not** be undone, which are:
-
-1. `/proc/sys/net/ipv4/ip_forward = 1` and `/proc/sys/net/ipv6/conf/all/forwarding = 1`
-2. dnsmasq (if used) in Apparmor complain mode
-3. hostapd (if used) in Apparmor complain mode
-4. Kernel module `nf_nat_pptp` loaded
-5. The wifi device which is used to create hotspot is `rfkill unblock`ed
-6. WiFi country code, if user assigns
-
-## Dependencies
-
-- bash
-- procps or procps-ng
-- iproute2
-- dnsmasq
-- iptables (or nftables with `iptables-nft` translation linked)
-- WiFi hotspot dependencies
-  - hostapd
-  - iw
-  - iwconfig (you only need this if 'iw' can not recognize your adapter)
-  - haveged (optional)
-  - qrencode (optional)
-
 ## TODO
 
-<details>
+Sooner is better:
+- Detect firewalld and make sure it won't interfere our interface
 
-- Compatibility with firewalld
+Future:
 - WPA3
 - Global IPv6
 - Explictly ban forwarding if not needed
 - Bring bridging method back
 
-</details>
-
 ## License
 
 linux-router is LGPL licensed
@@ -482,14 +536,4 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 </details>
 
-## Meet developer(s) and become one of them
 
-Visit [**my homepage** 🏡](https://garywill.github.io) to see **more tools and projects** 🛠️.
-
-> [❤️ Buy me a coffee](https://github.com/garywill/receiving/blob/master/receiving_methods.md) , this project took me lots of time! ([❤️ 扫个码打赏一个!](https://github.com/garywill/receiving/blob/master/receiving_methods.md))
-> 
-> 🥂 ( ^\_^) o自自o (^_^ ) 🍻
-
-🤝 Bisides, thank [create_ap](https://github.com/oblique/create_ap) by [oblique](https://github.com/oblique). This script was forked from create\_ap. Now they are quite different. (See `history` branch for how I modified create_ap). 🤝 Also thank those who contributed to that project.
-
-👨‍💻 You can be contributor, too! 🍃 There're some TO-DOs listed, at both [above](#todo) and [in the code file](https://github.com/garywill/linux-router/search?q=TODO&type=code). 🍃 Also some [unfulfilled enhancements in the Issues](https://github.com/garywill/linux-router/issues?q=is%3Aissue+is%3Aopen+label%3Aenhancement). Your name can be here!

lnxrouter

@@ -1,6 +1,6 @@
 #!/bin/bash
 
-VERSION=0.6.6
+VERSION=0.7.1
 PROGNAME="$(basename $0)"
 
 export LC_ALL=C
@@ -67,26 +67,28 @@ Options:
     -d                      DNS server will take into account /etc/hosts
     -e <hosts_file>         DNS server will take into account additional 
                             hosts file
+    --dns-nocache           DNS server no cache
     
     --mac <MAC>             Set MAC address
     --random-mac            Use random MAC address
  
     --tp <port>             Transparent proxy,
-                            redirect non-LAN TCP and UDP traffic to port.
+                            redirect non-LAN TCP and UDP(not tested) traffic to
-                            (usually used with '--dns')
+                            port. (usually used with '--dns')
     
   WiFi hotspot options:
     --ap <wifi interface> <SSID>
                             Create WiFi access point
     -p, --password <password>   
                             WiFi password
-    --qr                    Show WiFi QR code in terminal
+    --qr                    Show WiFi QR code in terminal (need qrencode)
     
     --hidden                Hide access point (not broadcast SSID)
     --no-virt               Do not create virtual interface
                             Using this you can't use same wlan interface
                             for both Internet and AP
-    -c <channel>            Channel number (default: 1)
+    --virt-name <name>      Set name of virtual interface
+    -c <channel>            Specify channel (default: use current, or 1 / 36)
     --country <code>        Set two-letter country code for regularity
                             (example: US)
     --freq-band <GHz>       Set frequency band: 2.4 or 5 (default: 2.4)
@@ -100,13 +102,28 @@ Options:
                             (defaults to /etc/hostapd/hostapd.accept)
     --hostapd-debug <level> 1 or 2. Passes -d or -dd to hostapd
     --isolate-clients       Disable wifi communication between clients
-    
-    --ieee80211n            Enable IEEE 802.11n (HT)
-    --ieee80211ac           Enable IEEE 802.11ac (VHT)
-    --ht_capab <HT>         HT capabilities (default: [HT40+])
-    --vht_capab <VHT>       VHT capabilities
-    
     --no-haveged            Do not run haveged automatically when needed
+    --hs20                  Enable Hotspot 2.0
+
+    WiFi 4 (802.11n) configs:
+    --wifi4                 Enable IEEE 802.11n (HT)
+    --req-ht                Require station HT (High Throughput) mode
+    --ht-capab <HT caps>    HT capabilities (default: [HT40+])
+
+    WiFi 5 (802.11ac) configs:
+    --wifi5                 Enable IEEE 802.11ac (VHT)
+    --req-vht               Require station VHT (Very High Thoughtput) mode
+    --vht-capab <VHT caps>  VHT capabilities
+    
+    --vht-ch-width <index>  Index of VHT channel width:
+                                0 for 20MHz or 40MHz (default)
+                                1 for 80MHz
+                                2 for 160MHz
+                                3 for 80+80MHz (Non-contigous 160MHz)    
+    --vht-seg0-ch <channel> Channel index of VHT center frequency for primary 
+                            segment. Use with '--vht-ch-width'
+    --vht-seg1-ch <channel> Channel index of VHT center frequency for secondary
+                            (second 80MHz) segment. Use with '--vht-ch-width 3'
 
   Instance managing:
     --daemon                Run in background
@@ -156,6 +173,7 @@ define_global_variables(){
     SHOW_DNS_QUERY=0  # log dns
     ETC_HOSTS=0
     ADDN_HOSTS=
+    DNS_NOCACHE=
     CONN_IFACE=    # which interface user choose to use to create network
     INTERNET_IFACE= # which interface to get Internet from
     THISHOSTNAME=   # this host's name the DNS tells clients 
@@ -176,13 +194,19 @@ define_global_variables(){
     HIDDEN=0 # hidden wifi hotspot
     WIFI_IFACE=
     CHANNEL=default 
+    HOTSPOT20=0 # For enabling Hotspot 2.0
     WPA_VERSION=2
     MAC_FILTER=0
     MAC_FILTER_ACCEPT=/etc/hostapd/hostapd.accept
     IEEE80211N=0
+    REQUIREHT=0
     IEEE80211AC=0
+    REQUIREVHT=0
     HT_CAPAB='[HT40+]'
     VHT_CAPAB=
+    VHTCHANNELWIDTH=0
+    VHTSEG0CHINDEX=0
+    VHTSEG1CHINDEX=0
     DRIVER=nl80211
     NO_VIRT=0 # not use virtual interface
     COUNTRY=
@@ -195,6 +219,7 @@ define_global_variables(){
     
     # script variables
     VWIFI_IFACE=  # virtual wifi interface name, if created
+    VIRT_NAME= # name to use for virtual interface if --virt-name is used
     AP_IFACE=     # can be VWIFI_IFACE or WIFI_IFACE
     USE_IWCONFIG=0  # some device can't use iw
     
@@ -322,6 +347,10 @@ parse_user_options(){
                 ADDN_HOSTS="$1"
                 shift
                 ;;
+            --dns-nocache)
+                shift
+                DNS_NOCACHE=1
+                ;;
             
             --isolate-clients)
                 shift
@@ -365,6 +394,10 @@ parse_user_options(){
                 CHANNEL="$1"
                 shift
                 ;;
+            --hs20)
+                shift
+                HOTSPOT20=1
+                ;;
             -w)
                 shift
                 WPA_VERSION="$1"
@@ -372,24 +405,47 @@ parse_user_options(){
                 shift
                 ;;
 
-            --ieee80211n)
+            --wifi4|--ieee80211n)
                 shift
                 IEEE80211N=1
                 ;;
-            --ieee80211ac)
+            --req-ht|--require-ht)
+                shift
+                REQUIREHT=1
+                ;;
+            --wifi5|--ieee80211ac)
                 shift
                 IEEE80211AC=1
                 ;;
-            --ht_capab)
+            --req-vht|--require-vht)
+                shift
+                REQUIREVHT=1
+                ;;
+            --ht-capab)
                 shift
                 HT_CAPAB="$1"
                 shift
                 ;;
-            --vht_capab)
+            --vht-capab)
                 shift
                 VHT_CAPAB="$1"
                 shift
                 ;;
+            --vht-ch-width|--vht-channel-width)
+                shift
+                VHTCHANNELWIDTH="$1"
+                shift
+                ;;
+            --vht-seg0-ch|--vht-seg0-channel)
+                shift
+                VHTSEG0CHINDEX="$1"
+                shift
+                ;;
+            --vht-seg1-ch|--vht-seg1-channel)
+                shift
+                VHTSEG1CHINDEX="$1"
+                shift
+                ;;
             --driver)
                 shift
                 DRIVER="$1"
@@ -399,6 +455,11 @@ parse_user_options(){
                 shift
                 NO_VIRT=1
                 ;;
+            --virt-name)
+                shift
+                VIRT_NAME="$1"
+                shift
+                ;;
 
             --country)
                 shift
@@ -505,6 +566,10 @@ is_interface() {
     [[ -d "/sys/class/net/${1}" ]]
 }
 
+is_vface_name_allocated(){
+    is_interface "$1" || [[ -f "$COMMON_CONFDIR/vfaces/${1}" ]]
+}
+
 get_interface_phy_device() { # only for wifi interface
     local x
     for x in /sys/class/ieee80211/*; do
@@ -626,19 +691,44 @@ get_interface_mac() {
     cat "/sys/class/net/${1}/address"
 }
 
+get_interface_pci_info() {  # pci id / model / virtual
+    is_interface "$1" || return
+    
+    local device_path
+    local pci_id
+    local pci_full
+    
+    device_path="$(readlink -f /sys/class/net/$1)"
+    
+    if [[ "$device_path" == "/sys/devices/pci"* ]]; then
+        pci_id="$(echo $device_path | sed 's/\//\n/g' | tail -n 3 |sed -n 1p)"
+        
+        if which lspci >/dev/null 2>&1 ; then
+            pci_full="$( lspci -D -nn | grep -E "^$pci_id " )"
+            echo "  PCI: $pci_full"
+        else
+            echo "  PCI: $pci_id"
+        fi
+    elif [[ "$device_path" == *"/virtual/"* ]]; then
+        echo "  virtual interface"
+    fi
+    # TODO usb
+    # TODO current driver
+}
+
 alloc_new_vface_name() { # only for wifi
     local i=0
-    local v_iface_name=
+    local v_iface_name="$VIRT_NAME"
-    while :; do
+    if [[ -z $VIRT_NAME ]]; then
-        v_iface_name="x$i${WIFI_IFACE}"
+        while :; do
-        if ! is_interface ${v_iface_name} && [[ ! -f $COMMON_CONFDIR/vfaces/${v_iface_name} ]]; then
+            v_iface_name="x$i${WIFI_IFACE}"
-            mkdir -p $COMMON_CONFDIR/vfaces
+            i=$((i + 1))
-            touch $COMMON_CONFDIR/vfaces/${v_iface_name}
+            is_vface_name_allocated ${v_iface_name} || break
-            echo "${v_iface_name}"
+        done
-            return
+    fi
-        fi
+    mkdir -p $COMMON_CONFDIR/vfaces
-        i=$((i + 1))
+    touch $COMMON_CONFDIR/vfaces/${v_iface_name}
-    done
+    echo "${v_iface_name}"
 }
 
 dealloc_vface_name() {
@@ -995,7 +1085,7 @@ allow_dhcp() {
 # TODO: use 'DNAT' instead of '--to-ports' to support other IP
 start_redsocks() {
     echo
-    echo "iptables: transparent proxy non-LAN TCP/UDP traffic to port ${TP_PORT}"
+    echo "iptables: transparent proxy non-LAN TCP and UDP(not tested) traffic to port ${TP_PORT}"
     if [[ $NO4 -eq 0 ]]; then
         iptb 4 n nat N lrt${$}${SUBNET_IFACE}-TP || die
         iptb 4 n nat A lrt${$}${SUBNET_IFACE}-TP -d 0.0.0.0/8 -j RETURN || die
@@ -1158,7 +1248,7 @@ _cleanup() {
 }
 
 clean_iptables() {
-    bash $CONFDIR/undo_iptables.sh
+    [[ -f $CONFDIR/undo_iptables.sh ]] && bash $CONFDIR/undo_iptables.sh
     
     [[ -f $CONFDIR/undo_iptables_2.sh ]] && bash $CONFDIR/undo_iptables_2.sh
 }
@@ -1173,15 +1263,15 @@ cleanup() {
     clean_iptables > /dev/null
     _cleanup 2> /dev/null
     
-    pgid=$(ps opgid= $$ |awk '{print $1}' )
+    #pgid=$(ps opgid= $$ |awk '{print $1}' )
-    echo "Killing PGID $pgid ..."
+    #echo "Killing PGID $pgid ..."
-    kill -15 -$pgid
+    #kill -15 -$pgid
-    sleep 1 
+    #sleep 1 
     echo "Cleaning up done"
     #kill -9 -$pgid
 }
 
-# NOTE function die() is designed not to be used before init_trap() executed
+# NOTE function die() is designed NOT to be used before init_trap() executed
 die() { # SIGUSR2
     echo "Error occured"
     [[ -n "$1" ]] && echo -e "\nERROR: $1\n" >&2
@@ -1464,7 +1554,7 @@ daemonizing_check(){
 check_wifi_settings() {
 
     if ! ( which iw > /dev/null 2>&1 && iw dev $WIFI_IFACE info > /dev/null 2>&1 ); then
-        echo "WARN: Can't use 'iw' to operate interfce '$WIFI_IFACE', trying 'iwconfig' (not as good as 'iw') ..." >&2
+        echo "WARN: Can't use 'iw' to operate interfce '$WIFI_IFACE', trying 'iwconfig' (not as good as 'iw') ... (Did you spell the interface name right?)" >&2
         USE_IWCONFIG=1
     fi
     
@@ -1480,14 +1570,6 @@ check_wifi_settings() {
         exit 1
     fi
 
-    if [[ $CHANNEL == default ]]; then
-        if [[ $FREQ_BAND == 2.4 ]]; then
-            CHANNEL=1
-        else
-            CHANNEL=36
-        fi
-    fi
-
     if [[ $FREQ_BAND != 5 && $CHANNEL -gt 14 ]]; then
         echo "Channel number is greater than 14, assuming 5GHz frequency band"
         FREQ_BAND=5
@@ -1543,6 +1625,18 @@ check_wifi_settings() {
         fi
         echo "WARN: If AP doesn't work, read https://github.com/oblique/create_ap/blob/master/howto/realtek.md" >&2
     fi
+
+    if [[ -z $VIRT_NAME ]]; then
+        if [[ ${#WIFI_IFACE} -gt 13 ]]; then
+            echo "WARN: $WIFI_IFACE has ${#WIFI_IFACE} characters which might be too long. If AP doesn't work, see --virt-name and https://github.com/garywill/linux-router/issues/44" >&2
+        fi
+    elif [[ ${#VIRT_NAME} -gt 15 ]]; then
+        echo "WARN: option --virt-name $VIRT_NAME has ${#VIRT_NAME} characters which might be too long, consider making it shorter in case of errors" >&2
+    fi
+
+    if [[ ! -z $VIRT_NAME ]] && is_vface_name_allocated $VIRT_NAME; then
+      echo "WARN: interface $VIRT_NAME aleady exists, this will cause an error"
+    fi
 }
 
 check_if_new_mac_valid() {
@@ -1594,20 +1688,21 @@ prepare_wifi_interface() {
     
     if [[ $NO_VIRT -eq 0 ]]; then
     ## Will generate virtual wifi interface
+    
+        # TODO move this to check_wifi_settings() ?
         if is_interface_wifi_connected ${WIFI_IFACE}; then
             WIFI_IFACE_FREQ=$(iw dev ${WIFI_IFACE} link | grep -i freq | awk '{print $2}')
             WIFI_IFACE_CHANNEL=$(ieee80211_frequency_to_channel ${WIFI_IFACE_FREQ})
-            echo "${WIFI_IFACE} already in channel ${WIFI_IFACE_CHANNEL} (${WIFI_IFACE_FREQ} MHz)"
+            
-            if is_5ghz_frequency $WIFI_IFACE_FREQ; then
+            echo "${WIFI_IFACE} already working in channel ${WIFI_IFACE_CHANNEL} (${WIFI_IFACE_FREQ} MHz)"
-                FREQ_BAND=5
+            
-            else
+            if [[ $CHANNEL == default ]]; then
-                FREQ_BAND=2.4
+                echo "Use wifi adapter current channel $WIFI_IFACE_CHANNEL as target channel"
-            fi
-            if [[ $WIFI_IFACE_CHANNEL -ne $CHANNEL ]]; then
-                echo "Channel fallback to ${WIFI_IFACE_CHANNEL}"
                 CHANNEL=$WIFI_IFACE_CHANNEL
-            else
+            fi
-                echo
+            
+            if [[ $WIFI_IFACE_CHANNEL -ne $CHANNEL ]]; then
+                echo "WARN: Wifi adapter already working in channel ${WIFI_IFACE_CHANNEL}, which is different than target channel $CHANNEL" >&2
             fi
         fi
 
@@ -1620,13 +1715,28 @@ prepare_wifi_interface() {
             echo "${VWIFI_IFACE} created"
         else
             VWIFI_IFACE=
-            die "Failed creating virtual WiFi interface. Maybe your WiFi adapter does not fully support virtual interfaces. Try again with '--no-virt'"
+            if [[ ! -z ${VIRT_NAME} ]] && [[ ${#VIRT_NAME} -gt 15 ]]; then
+              die "Failed creating virtual WiFi interface. This is likely because you have set a long name for your virtual interface using --virt-name, try making it shorter'"
+            elif [[ -z ${VIRT_NAME} ]] && [[ ${#WIFI_IFACE} -gt 13 ]]; then
+              die "Failed creating virtual WiFi interface. This is likely because your interface name is too long. Try using '--virt-name <shorter interface name>'"
+            else
+              die "Failed creating virtual WiFi interface. Maybe your WiFi adapter does not fully support virtual interfaces. Try again with '--no-virt'"
+            fi
         fi
         
         AP_IFACE=${VWIFI_IFACE}
     else # no virtual wifi interface, use wifi device interface itself
         AP_IFACE=${WIFI_IFACE}
     fi
+    
+    if [[ $CHANNEL == default ]]; then
+        echo "Channel not specified, use default"
+        if [[ $FREQ_BAND == 2.4 ]]; then
+            CHANNEL=1
+        else
+            CHANNEL=36
+        fi
+    fi
 }
 
 decide_subnet_interface() {
@@ -1688,6 +1798,10 @@ write_hostapd_conf() {
 		EOF
     fi
 
+    if [[ $HOTSPOT20 -eq 1 ]]; then
+        echo "hs20=1" >> "$CONFDIR/hostapd.conf"
+    fi
+
     if [[ $IEEE80211N -eq 1 ]]; then
         cat <<- EOF >> "$CONFDIR/hostapd.conf"
 			ieee80211n=1
@@ -1695,14 +1809,40 @@ write_hostapd_conf() {
 		EOF
     fi
 
+    if [[ $REQUIREHT -eq 1 ]]; then
+        echo "require_ht=1" >> "$CONFDIR/hostapd.conf"
+    fi
+
     if [[ $IEEE80211AC -eq 1 ]]; then
         echo "ieee80211ac=1" >> "$CONFDIR/hostapd.conf"
     fi
 
+    if [[ $REQUIREVHT -eq 1 ]]; then
+        echo "require_vht=1" >> "$CONFDIR/hostapd.conf"
+    fi
+
     if [[ -n "$VHT_CAPAB" ]]; then
         echo "vht_capab=${VHT_CAPAB}" >> "$CONFDIR/hostapd.conf"
     fi
 
+	if [[ $VHTCHANNELWIDTH -gt 0 ]]; then
+		cat <<- EOF >> "$CONFDIR/hostapd.conf"
+			vht_oper_chwidth=${VHTCHANNELWIDTH}
+		EOF
+	fi
+
+	if [[ $VHTSEG0CHINDEX -gt 0 ]]; then
+		cat <<- EOF >> "$CONFDIR/hostapd.conf"
+			vht_oper_centr_freq_seg0_idx=${VHTSEG0CHINDEX}
+		EOF
+	fi
+
+	if [[ $VHTSEG1CHINDEX -gt 0 ]]; then
+		cat <<- EOF >> "$CONFDIR/hostapd.conf"
+			vht_oper_centr_freq_seg1_idx=${VHTSEG1CHINDEX}
+		EOF
+	fi
+
     if [[ $IEEE80211N -eq 1 ]] || [[ $IEEE80211AC -eq 1 ]]; then
         echo "wmm_enabled=1" >> "$CONFDIR/hostapd.conf"
     fi
@@ -1796,6 +1936,10 @@ write_dnsmasq_conf() {
 			no-poll
 		EOF
     fi
+    if [[ $DNS_NOCACHE -eq 1 ]]; then
+        echo "cache-size=0" >> "$CONFDIR/dnsmasq.conf"
+        echo "no-negcache" >> "$CONFDIR/dnsmasq.conf"
+    fi
     if [[ $IPV6 -eq 1 ]];then
         cat <<- EOF  >> "$CONFDIR/dnsmasq.conf"
 			listen-address=${GATEWAY6}
@@ -1846,7 +1990,7 @@ run_wifi_ap_processes() {
     #    sleep 1
     #done
     #echo -n "hostapd PID: " ; cat $CONFDIR/hostapd.pid
-    pid_watchdog $HOSTAPD_PID 10 "hostapd failed" &
+    pid_watchdog $HOSTAPD_PID 10 "hostapd failed. (tip: try '--hostapd-debug' to get some debug info)" &
     sleep 3
 }
 
@@ -1928,8 +2072,7 @@ echo
 echo "PID: $$"
 
 TARGET_IFACE="$(decide_target_interface)" || exit 1 # judge wired (-i CONN_IFACE) or wireless hotspot (--ap $WIFI_IFACE)
-echo "Target interface is ${TARGET_IFACE} ($(get_interface_mac $TARGET_IFACE))"
+echo "Target interface is ${TARGET_IFACE} ($(get_interface_mac $TARGET_IFACE)) $(get_interface_pci_info $TARGET_IFACE)"
-# TODO: show interface type, device model and pci/usb id (hwdata  pci.ids), current driver
 
 if [[ "$MAC_USE_RANDOM" -eq 1 ]] ; then
     NEW_MACADDR="$(generate_random_mac)"
@@ -2065,7 +2208,7 @@ fi
 [[ $NO_DNSMASQ -eq 0 ]] && ( allow_dhcp ; start_dnsmasq )
 
 echo 
-echo "== Setting up completed, now linux-router is working =="
+echo "== Setting up completed, now linux-router should be working =="
 
 #============================================================
 #============================================================