I've run into a little problem. The solution is probably pathetically simple and I will want to kick myself for being unable to find the answer...nevertheless I've searched for most of the afternoon.
I connect to my openvpn from xoom as follows :
Open terminal and type the following:
su
cd /pathto/myopenvpnfolder (in my case /sdcard/openvpn)
openvpn clientconfigfile.ovpn
everything connects fine and works flawlessly
The problem is that I cannot disconnect unless I reboot the xoom.
Do you know the command line for this?
I know that there is an app called 'openvpn settings' that automates this process but 1), I want to understand syntax and 2), the app will not sustain a connection and nags my notification area. Any ideas? Thank you in advance.
Sent from my Xoom using Tapatalk
No one has any idea?
Sent from my Nook Color using Tapatalk
Ok
First of all -- I tried some basic commands on my phone -- without openvpn specifically, so try some things here -- worst case scenario you will have to reboot.
I believe openvpn creates another network interface. tiwlan0 is the main networking interface on my phone (D1). Your interface my vary. The best way I can advise you to look for your interface name is to take a look at dmesg. So at the command line, type dmesg and then scroll through the output.
Here is the relevant networking connections in mine:
<6>[18427.544403] TIWLAN: 2235.055000:
<6>[18427.548034] TIWLAN: 2235.058662: -----------------------------------------
------------
<6>[18427.559783] TIWLAN: 2235.070412: Driver Version : WiLink_Driver_6.1.0.0.1
31
<6>[18427.575408] TIWLAN: 2235.086037: Firmware Version: Rev 6.1.5.44.1
<6>[18427.601867] TIWLAN: 2235.112465: Station ID : 00-26-BA-3C-62-CB
<6>[18427.625610] TIWLAN: 2235.136208: -----------------------------------------
------------
<6>[18427.644744] TIWLAN: 2235.155342:
<4>[18429.784362] wlanDrvIf_Open
<6>[18429.787628] ADDRCONF(NETDEV_UP): tiwlan0: link is not ready
<6>[18429.832733] ADDRCONF(NETDEV_CHANGE): tiwlan0: link becomes ready
<6>[18430.268096] TIWLAN: 2236.929695: configHW_to_connected: *** NEW CONNECTION
***
<7>[18440.122283] tiwlan0: no IPv6 routers present
In order to list the network IP address listed with the specific interface I then did:
ifconfig tiwlan0
Which resulted in the following:
# ifconfig tiwlan0
ifconfig tiwlan0
tiwlan0: ip 192.168.1.105 mask 255.255.255.0 flags [up broadcast running multica
st]
Now I believe openvpn will create another network adapter -- something like tun0 or tap0 depending if you are bridging or routing your vpn (which depends which is specified in your .conf file). To bring down the interface manually, all you would do (assuming your rooted):
ifconfig <interface_name> down
I borrowed these commands from this tutorial (which will help a little bit -- but be warned, android doesn't have the full network-tools implementation so some of the commands with various switches will not be complete): http://ubuntuforums.org/showthread.php?t=571188
Hopefully this will get you on the correct track!!!!
Awesome! First I want to thank you for answering...second I want to kick myself for not trying basic Linux networking commands...I made a mountain out of a mole hill! Thank you muchly again!
Sent from my Xoom using Tapatalk
Dollyllama said:
Awesome! First I want to thank you for answering...second I want to kick myself for not trying basic Linux networking commands...I made a mountain out of a mole hill! Thank you muchly again!
Sent from my Xoom using Tapatalk
Click to expand...
Click to collapse
hey im a noob....I have a openvpn server at home but I cannot figure out exactly how to use it on the XOOM or on my Atrix. Could you be kind enough to give me step by step guide to use openvpn on Xoom, when you get time. Thank you so much.
What I wanted was a simple, secure way to access my home computer remotely from my android phone. I know there are vpn options but I’ve seen that cause battery drain issues if in constant use, and also is more than I wanted/needed to setup. I know I could just setup a ssh server but leaving port 22 open on the remote computer for anyone to scan and hack the password seemed too insecure for me. So I came up with this solution and have been using it for about 2 years now without any problems. I thought maybe I should share this method since it may be of use to someone else and I don’t know of anyone else putting all these together for use with android.
What this does:
By running a small script on your android phone in terminal (only 2 commands), your phone knocks 3 specific ports, in a specific order (like a combination lock), your remote computer recognizes this order and opens port 22 for 10 sec. Your script then ssh’s the remote computer on port 22 and you log in. The port 22 on the remote computer closes so no one else can see it, but the keep-alive feature keeps your ssh session open so you can do whatever you need, for as long as your like, without worrying about someone port sweeping the remote computer and seeing the port open, or brut forcing a ssh password on it. You with me so far?
Now the ssh session also uses port forwarding to forward port 5900 from the remote computer to port 5900 on the localhost of the android phone. Now you can open your vnc client and connect to the remote computer through your ssh tunnel and see your x11 desktop. So you know also have a secure VNC connection! All this is done securely and only runs ondemand.
While this may look like a lot to setup, it’s actually quite easy and should only take about 15min tops. This tutorial should be complete but if I’ve forgotten anything, let me know and I’ll be sure to update this page.
In other words, run two simple commands within a script and you have secure access to your remote computer from your phone! Enjoy!
Pros:
- Secure
- Works on 3G and wifi
- Runs on all android versions
- Works on all x11 GUI’s (gnome, kde, etc). Assuming a VNC session is also desired.
- Fun!
Problems:
- This only works on linux computers, although I’m sure there is a way to setup port knocking on windows. I have no use for this, but if people are interesting, I can add a way to my tutorial as well.
Howto:
Setup Remote Computer:
First we need to setup the remote computer. This is geared towards Debian/Ubuntu but small adjustments should have it working on all distros (I’m using Debian Squeeze personally). Let’s begin:
First we need to install a few packages if not already there:
Code:
apt-get install openssh-server x11vnc knockd
Now lets configure your ssh daemon. Using nano or another text editor, edit /etc/ssh/sshd_config:
Change the following line to read as follows:
Code:
PermitRootLogin no
This will disable root login, so you will login in as a user and then su to root (You can leave root login if desired, it’s just less secure and not recommended).
Next we need to edit our iptables, so open /etc/network/if-pre-up.d/iptables and add the following:
MAKE A BACKUP FIRST OF THIS FILE
Code:
# Accepts all established inbound connections
iptables -A INPUT -i eth0 -m state --state ESTABLISHED,RELATED -j ACCEPT
# Allows all outbound traffic
iptables -A OUTPUT -j ACCEPT
# Allow ping
iptables -A INPUT -p icmp -m icmp --icmp-type 8 -j ACCEPT
# log iptables denied calls (access via 'dmesg' command)
iptables -A INPUT -m limit --limit 5/min -j LOG --log-prefix "iptables denied: " --log-level 7
# Reject all other inbound - default deny unless explicitly allowed policy:
iptables -A INPUT -j REJECT
iptables -A FORWARD -j REJECT
Now we setup our port knocking. Edit /etc/knockd.conf:
Code:
[options]
UseSyslog
[openSSH]
sequence = port1,port2,port3
seq_timeout = 5
command = /sbin/iptables -I INPUT -p tcp -m state --state NEW --dport 22 -j ACCEPT
cmd_timeout = 10
stop_command = iptables -I INPUT -p tcp -m state --state NEW --dport 22 -j DROP
tcpflags = syn
[closeSSH]
sequence = port1,port2,port3
seq_timeout = 5
command = /etc/init.d/ssh stop
tcpflags = syn
The section [openSSH] is what opens the port for 10 sec by running the iptables command and then drops the packets after the time expires, running the stop_command. The section [closeSSH] is not needed. It was a failsafe I use in case I want to disable ssh if I thought I was getting hacked and could not login. This is also left to show how you can use the knocking to run different commands using another sequence of ports (for ftp, etc.)
Now lets restart the network interface and restart the knock daemon:
Code:
ifconfig eth0 down #adjust to whatever interface you use normally
ifconfig eth0 up
dhclient
/etc/init.d/knockd restart
/etc/init.d/sshd restart
Test your internet and make sure it works. To make sure you have it setup to run on boot, first determine your runlevel:
Code:
runlevel
Make sure knockd, ssh are in the /etc/rcX.d (where X equals your runlevel). If not, add it
Code:
ln -s /etc/init.d/knockd /etc/rcX.d/S02knockd
And so on for shh if needed, (again, adjust X to equal your runlevel)
Setup X11VNC password:
Code:
x11vnc --store password
create a script for ~/bin/x11vncserver
add this to the script
Code:
#!/bin/bash
x11vnc -safer -forever -usepw -noxdamage
The “-noxdamage” fixes a display problem of the desktop not updating in the android vnc client. Now if using gnome and you only care about vnc login for one user then, goto System → Preferences → Startup Applications → Add →
Name = VNC Server
Command = x11vncserver &
Or add to GDM for access to any user, add to /etc/gdm3/Init/Default:
Code:
x11vnc -safer -forever -usepw -noxdamage
DONE! (KDE will be similar but slightly different to load on login, post if help is needed)
Setup android phone:
create script called knockh in /system/xbin. Then add this:
Code:
nc -z [ipaddress] port1 port2 port3
ssh -L 5990:localhost:5900 [email protected][ipaddress]
Replaces the ipaddress with your own (google “what is my ip” if you don’t know your external ip). Replace the ports with the ones used in the config file above for knockd. Change the user to whatever user has ssh rights. Then
Code:
chmod 755 /system/xbin/knockh
Now run knockh in the terminal and you should see a login for ssh on your remote computer.
Next download “android-vnc-viewer” from the market (it’s free). Create a new connection by selecting “new” from the dropdown box.
Create a nickname, enter your x11vnc pasword, address is “localhost” and port is “5900”. For 3G connections, I recommend 8 colors, for wifi 256. I also check the “Local mouse pointer” in the checkbox. Now click connect and see your desktop!
(If you are on your local wifi network be sure to create another connection for your local ip address)
Fixes:
Keep in mind this is for remote networks, if you are on your local lan, this won’t work without changing the ip address.
If using a router or modem, setup port forwarding to your remote computer for TCP ports 5900, 22, port1, port2, port3 (your port knocking ports). Also make sure to setup a static dhcp for the remote computer so your router/modem doesn’t change it’s ip address and you can’t connect.
If you are using an ISP that doesn’t give you a static ip address for your router, you will not be able to login whenever they change it, you’ll have to update the script first with the new IP. A solution is to setup a dynamic dns, using dyndns.org or something similar. Free options are out there, just google it.
I hope this helps, please post if you have any questions, comments, etc. Enjoy!
-Mike
On some roms, the busybox version of "nc" does not allow the -z command for knocking the proper ports. I've pulled the version of it from CM 7.2 and put in my /system/xbin and full functionality has been retained. I've included both "nc" and "ssh" here and they should work fine if you are missing them. (Tested on my EVO LTE running mostly stock Sense ICS, but this is fine for other android versions)
nc
ssh
Hope this helps!
-Mike
Highlights
100% open source (GPLv2+)
No ads
One-click connection (batch mode)
Supports RSA SecurID and TOTP software tokens
Keepalive feature to prevent unnecessary disconnections
Compatible with ARMv7, x86, and MIPS devices
No root required
Based on the popular OpenConnect Linux package
Click to expand...
Click to collapse
Requirements
Android 4.0 (ICS) or higher (with working VpnService + tun infrastructure)
An account on a suitable VPN server
Click to expand...
Click to collapse
Downloads
Binaries are attached to this post under the downloads tab.
Google Play: https://play.google.com/store/apps/details?id=app.openconnect
Source code: https://github.com/cernekee/ics-openconnect
F-Droid: https://f-droid.org/repository/browse/?fdid=app.openconnect
Click to expand...
Click to collapse
(note that the F-Droid binaries are signed by a different key than the official releases)
Changelog
Code:
v1.11 - 2015/02/21
- Fix "Unknown compression type 0" errors when CSTP and DTLS use
different compression settings
Older changelogs:
Code:
v1.10 - 2015/02/08
- Fix CSD script problem on Lollipop (bug #1)
- Fix IPv6 address display on status window (bug #2)
- Enable LZ4 compression support
- Identify as a mobile client when Android or iOS is selected
- Update to OpenConnect v7.04+, GnuTLS 3.2.21
v1.02 - 2014/09/02
- Fix regression on certificate handling
v1.01 - 2014/08/29
- Add Spanish translations (thanks to teosoft)
- Fix regression on CSD scripts starting with "#!/bin/sh"
- Improve error messages on broken ROMs that throw exceptions when
starting a VpnService
- Fix intermittent fragment-related crashes on ICS
v1.00 - 2014/08/10
- Fix problems storing >8kB certificates on some ROMs
- Clean up seldom-used menu items and move some options into General Settings
or About
- Integrate Xposed module for bypassing the VPN confirmation dialog
- Switch to ACRA for problem reporting
v0.96 - 2014/07/06
- Force a minimum MTU of 1280 on KK due to bugs in 4.4.3 and 4.4.4 ROMs:
https://code.google.com/p/android/issues/detail?id=70916
- Fix navigation anomalies (weird Back button behavior) seen after
re-entering OpenConnect from one of the Notifications
v0.95 - 2014/06/14
- Show the auth dialog <message> text in case it contains useful information
- Add German translations (thanks to Ingo Zansinger <[email protected]>)
- Add Chinese translations
- Add Advanced options for changing Dead Peer Detection timeout and enabling Perfect Forward Secrecy
- Clean up a bunch of lint warnings and unused strings/files
- Try to generate a human-readable profile name when adding a new VPN
v0.91 - 2014/06/01
- Fix bugs involving saved authgroups
- Fix batch mode error handling
- Update to GnuTLS 3.2.15 to fix GNUTLS-SA-2014-3 / CVE-2014-3466
v0.9 - 2014/04/26
- Add new "Send feedback" screen
- Add new "SecurID info" screen for RSA soft token users
- Allow changing settings and using other menu options (about, SecurID,
send feedback, etc.) while connected
- Update FAQ and provide some links to relevant XDA posts
v0.81 - 2014/04/06
- Fix potential issue recognizing certificates stored in VPN profiles
created with <= v0.7
v0.8 - 2014/04/02
- Fix hangs after reconnect if DTLS is disabled
- Fix incorrect storage of PKCS#12 certificates
- Remove unnecessary passphrase prompts on unencrypted certificates
- Add a workaround for ASA certificate request quirks
- Fix FC when attempting to import an OpenVPN profile
v0.7 - 2014/03/08
- Update GnuTLS to address CVE-2014-0092
- Fix FC and other misbehavior on IPv6 connections
- Update to libopenconnect 5.99+
- Fix/delete several broken translations
- Minor improvements to the auth form UI
- Switch curl from OpenSSL to GnuTLS and remove advertising clauses
v0.6 - 2014/02/09
- First release in Google Play Store
- Change to new "big O" launcher icon
- Avoid displaying error alerts if the user terminated the connection
- Try to make the libopenconnect build process more robust, and strip *.so
files to conserve space
v0.5 - 2014/02/01
- Fix "living dead" connections (can't pass data after reconnection due to
DTLS parameter mismatches)
- Add FAQ tab in response to user feedback
- Move log window into a tab
- Reorganize action bar so that the most important items (Status/Log/FAQ)
are tabs, and less important items (Settings/About) are in the menu
- Fix KeepAlive socket errors on KitKat devices
- Other UI and documentation fixes
- Add split tunnel configuration options
- Improve icons
v0.2 - 2014/01/18
- Allow SecurID token import via URI or text file
- Newly reworked "status" tab with uptime, error alerts, IP addresses,
etc.
- Fix a couple of bugs involving screen rotation / activity redraw on
the log window
- Prompt for hostname instead of profile name when adding a new VPN, to
help avoid "empty hostname" mistakes
- Numerous other UI improvements and fixes
- Remove "reconnect on boot" until it works properly
- Try to accommodate Linux CSD wrapper scripts starting with "#!/bin/bash"
Click to expand...
Click to collapse
FAQ
Q: What is this app used for?
A: OpenConnect is used to access virtual private networks (VPNs) which utilize the Cisco AnyConnect SSL VPN protocol. A typical use case might involve logging into your workplace remotely to check email after hours.
If in doubt, check with your I.T. administrator to see if a suitable service is available.
Q: How do I get started?
A: In most cases, you'll just need to create a profile and enter the hostname of the VPN gateway. The other fields in the profile are all optional and should be left alone unless there is a specific need to change them.
Once you've set up the profile, select the VPN entry and OpenConnect will attempt to establish a new session. If this fails, the "Log" tab may provide helpful diagnostic information.
Q: How do I authenticate using an SSL client certificate?
A: Copy your certificate files to Android's external storage directory (nominally /sdcard or the Downloads folder), then edit the VPN profile and make the following changes:
P12 or PFX file: select "User certificate", pick the file from the list, then touch "select". Leave "Private key" blank.
Single PEM/CRT/CER file: same as above.
Separate PEM/CRT/CER and KEY files: populate "User certificate" with the certificate file, and "Private key" with the key file.
When finished, delete the certificate files from external storage so they cannot be stolen by other apps.
If you are generating your own keys (e.g. for use with your ocserv gateway), some basic CA setup instructions are posted here.
Q: Will OpenConnect work with non-AnyConnect VPNs?
A: Unfortunately the software design is tied very closely to the AnyConnect requirements and the libopenconnect interfaces. Therefore it only works with Cisco AnyConnect and ocserv gateways.
Q: Will OpenConnect work with Cisco IPsec VPNs running on an ASA?
A: OpenConnect supports SSL VPN (CSTP + DTLS) only.
Q: How do I import a SecurID software token?
A: If you have an URL that starts with "com.rsa.securid.iphone://" or "http://127.0.0.1/securid/" in your email, click on it and tell OpenConnect to add it to the desired VPN profile. If you just have a raw token string then write it to a text file, copy it under /sdcard, click "Token string" in the VPN profile editor, then select the filename.
If you have an "sdtid" XML file, copy it to /sdcard and then import it.
Q: Is it possible to skip all login prompts when connecting?
A: If you have saved your username, password, or other credentials, or if you are using SecurID or certificate authentication, you can try enabling "Batch Mode" in the VPN profile to skip the login dialogs. If you need to change your saved password later or have trouble connecting, just disable batch mode.
The VPN warning dialog is a security feature built into the Android OS. It cannot be bypassed by OpenConnect, but if your device is rooted, you can try installing the Xposed Framework and then activating the Auto VPN Dialog Confirm module. Some notes on this are posted here.
Due to the user interaction required by these dialogs, it is not always possible to reliably start up the VPN in the background. So a "start-on-boot" feature is not currently provided.
Q: How do I improve battery life while the VPN is up?
A: One option is to select "Pause when asleep" under Settings. The downside is that VPN access will be temporarily stopped when the screen is off. Also, ASA gateways sometimes get annoyed with constant reconnections and may prematurely terminate your session after a few days.
Another option is to contact your server administrator and request that they disable dead peer detection (DPD), increase the idle timeout to >1hr, and increase the keepalive interval to ~5min or so.
Q: How do I use OpenConnect with AFWall+?
A: There are a few caveats to keep in mind when using an Android firewall with VPN:
* If you run KitKat, use Android 4.4.2 or higher and AFWall 1.2.8 or higher. Android 4.4 and 4.4.1 have a serious TCP MSS bug which causes stalled connections and/or poor performance. AFWall <=1.2.7 does not have the extra logic needed to handle the routing changes in KitKat.
* Always allow traffic from the VPN app on all interfaces. In particular, you should whitelist VPN traffic from OpenConnect, as OpenConnect sends DNS requests over the VPN interface every few minutes to help keep the connection from timing out.
Q: Are any apps incompatible with VPN?
A: Apps which perform their own DNS resolution, such as Firefox, may have issues picking up the latest system DNS settings when connecting to the VPN. This can be a problem if your system DNS servers are not accessible over the VPN's routes, or if you are trying to look up hostnames that do not have public (internet) DNS entries.
Q: Under what circumstances will OpenConnect request root?
A: There are two root-only features shown under Settings; both are disabled by default. One setting works around a ROM bug in CM9 which sets incorrect permissions on /dev/tun, preventing VpnService from passing traffic to the tunnel interface; the other setting loads tun.ko on ROMs that neglect to load it by default.
Based on user feedback and testing, future releases may autodetect these conditions.
Q: How do I send a problem report?
A: Navigate to Log -> (menu) -> Send log file. Please be sure to furnish a complete, accurate description of the issue you are seeing, as the logs do not always show a smoking gun.
Click to expand...
Click to collapse
TODO
Translations - I will set up the necessary infrastructure if there are volunteers
Compatibility testing
Add x509 certificate parsing/validation in the profile editor
Enable Android keystore support
Proxy support
Split tunnel DNS?
Click to expand...
Click to collapse
MISC
Using OpenConnect + ocserv (on a VPS) to bypass China's Great Firewall (GFW): link
XDA:DevDB Information
OpenConnect, App for the Android General
Contributors
cernekee
Source Code: https://github.com/cernekee/ics-openconnect
Version Information
Status: Testing
Created 2014-01-18
Last Updated 2015-02-21
hello cernekee,
I was using smoothconnect on my note3 and It was working just fine, but now after I update my note3 to kitkat it surfs only couple of things like "play store", google search, and whatsup. but all other web sites and programs do not!!
now I tried out this program "open connect" with some hope but nope, I does the same thing. It only opens play store and google search but no other things.
I wonder what cause this problem, any suggestions please??
msm88now said:
hello cernekee,
I was using smoothconnect on my note3 and It was working just fine, but now after I update my note3 to kitkat it surfs only couple of things like "play store", google search, and whatsup. but all other web sites and programs do not!!
now I tried out this program "open connect" with some hope but nope, I does the same thing. It only opens play store and google search but no other things.
I wonder what cause this problem, any suggestions please??
Click to expand...
Click to collapse
Sometimes an MTU or TCP MSS problem could cause this symptom. What kind of gateway are you connecting to? Are you the admininstrator?
Older versions of KitKat did have an MSS problem; I think 4.4.1+ is OK: https://code.google.com/p/android/issues/detail?id=61948
There are a few other outstanding problems on <= 4.4.2: http://www.androidpolice.com/2014/0...n-routing-fixes-are-planned-for-some-of-them/
Do you see the same problem connecting from other systems, like a Windows PC, or even the Cisco AnyConnect Android app?
Hi cernekee,
I have an openSSL Cisco vpn connection provided by my university, I hooked it with D-615 Dlink router through DHCP.
Cisco AnyConnect for andriod does not work on our university network because it asks for a certificate which my uni does not provide. that's why I'm using smoothconnect.
anyways, right now I have a flawless connection on my all devices on my room's wireless like my both Win7 laptops and my galaxy S2 andriod 4.1.2.
all work except my note 3 after I updated it to (4.4.2). I don't know if it's a IPv6 or MTU problem,
I tried to decrease MTU value in smoothconnect but with no success. as Cisco stated in: AnyConnect Android 4.4 (KitKat) Compatibility Update (CSCul28340)
any suggestions please???
msm88now said:
Hi cernekee,
I have an openSSL Cisco vpn connection provided by my university, I hooked it with D-615 Dlink router through DHCP.
Cisco AnyConnect for andriod does not work on our university network because it asks for a certificate which my uni does not provide.
Click to expand...
Click to collapse
I don't see this university's VPN requesting a certificate (i.e. SSL client cert). It just asks for a group/username/password.
Are you getting an error that says that the gateway is not licensed for mobile, after you enter your password?
that's why I'm using smoothconnect.
anyways, right now I have a flawless connection on my all devices on my room's wireless like my both Win7 laptops and my galaxy S2 andriod 4.1.2.
all work except my note 3 after I updated it to (4.4.2). I don't know if it's a IPv6 or MTU problem,
I tried to decrease MTU value in smoothconnect but with no success. as Cisco stated in: AnyConnect Android 4.4 (KitKat) Compatibility Update (CSCul28340)
any suggestions please???
Click to expand...
Click to collapse
Can you grab a packet capture when you're seeing the connectivity failures, and email me the result? e.g.
Code:
adb push tcpdump /data/local/tmp
adb shell
cd /data/local/tmp
su
chmod 755 tcpdump
./tcpdump -n -i tun0 -w out.pcap
yes that's right, Cisco anyconnect asks only for username/ password but when I try to start a connection it ends up with no license error!
that's way I'm using smoothconnect and now openconnect on my both andriod phones.
now for my problem, I didn't get what do you mean by connectivity failure because I'm not getting any connectivity failure messages on my note3 after update to 4.4.2 neither on smoothconnect nor on openconnect. it connects as usual and I can see some traffic packets are being transfered but I can only surf google serch, youtube and some other stuff like play store and whatsup. whenever I try to surf any other website like for example bbc news the browser( chrome, opera, Dolfin..) just waits and then ends up with nothing like there is no internet connection!
did I explain my problem clearly? is it an Ipv6 problem? I'm really confused and frustrated
msm88now said:
yes that's right, Cisco anyconnect asks only for username/ password but when I try to start a connection it ends up with no license error!
Click to expand...
Click to collapse
OK. This is because the Cisco mobile clients look for an "X-CSTP-License: accept" header from the gateway after authenticating, to see if the operator has paid extra to support the Cisco mobile client. libopenconnect-based clients (including SmoothConnect) do not require this header.
now for my problem, I didn't get what do you mean by connectivity failure because I'm not getting any connectivity failure messages on my note3 after update to 4.4.2 neither on smoothconnect nor on openconnect. it connects as usual and I can see some traffic packets are being transfered but I can only surf google serch, youtube and some other stuff like play store and whatsup. whenever I try to surf any other website like for example bbc news the browser( chrome, opera, Dolfin..) just waits and then ends up with nothing like there is no internet connection!
Click to expand...
Click to collapse
I can take a look at this to see what is happening. Just start up tcpdump to capture the tun0 traffic (see above instructions), then try visiting the BBC news site and maybe a few other non-working sites. Then hit control-C to interrupt tcpdump, make sure there is some data in the pcap file, and email me the pcap file.
cernekee said:
I can take a look at this to see what is happening. Just start up tcpdump to capture the tun0 traffic (see above instructions), then try visiting the BBC news site and maybe a few other non-working sites. Then hit control-C to interrupt tcpdump, make sure there is some data in the pcap file, and email me the pcap file.
Click to expand...
Click to collapse
Hi,
I don't know how to make Tcpdump on my note3 not to mention hitting the control-c on andriod. what instruction did you mean?
msm88now said:
I don't know how to make Tcpdump on my note3 not to mention hitting the control-c on andriod. what instruction did you mean?
Click to expand...
Click to collapse
Do you have a friend who is familiar with ADB, rooting phones, etc. who might be able to help out in person?
You could also try something like Shark for Root, or follow this video. Make sure you capture on the tun0 interface so that we can see what is happening on the VPN tunnel. If you capture from the wifi interface you'll still see traffic, but everything will be encrypted so it will not be possible to diagnose the failure.
I got it. first I rooted my note3 then I followed the instruction in the video and here it is, I hope it's what you asked me for. waiting for your diagnosis, fingers crossed
msm88now said:
I got it. first I rooted my note3 then I followed the instruction in the video and here it is, I hope it's what you asked me for. waiting for your diagnosis, fingers crossed
Click to expand...
Click to collapse
According to this trace (partial screenshot attached), the Note 3 is advertising an MSS of 1460 bytes on IPv4 TCP connections. This looks abnormally high for a VPN interface; the other direction is using an MSS of 1380, which looks more realistic. The MSS for IPv4 would normally be the tun0 MTU minus 40 bytes. I am assuming this means the MSS is being computed from the 1500-byte wlan0/eth0 MTU, not the smaller tun0 MTU.
When Google fixed the MSS bug in Android 4.4.1, they left the following comments in the changelog:
Code:
commit ca5b4e8d0d8219273ecf0961ed6e8c47ab5d798a
Author: JP Abgrall <[email protected]>
Date: Wed Nov 20 17:27:01 2013 -0800
SecondaryTableController: force the MSS to match pmtu on TCP SYN
Without this change, the VPN sets up a tun/ppp that needs a small
MTU, and during TCP SYN the MSS will end up matching the outgoing iface
MTU which is potentially too big.
This leads to connection flakiness. The wrong MSS is visible by
tcpdump-ing on the tun/ppp device.
With this change, the MSS now is correct.
[b]It requires the kernel to be configured with
CONFIG_NETFILTER_XT_TARGET_TCPMSS=y
If kernel is not configured, it silently fails.[/b]
Bug: 11579326
Change-Id: I254d8c39435b92dff91931e461e1efb8b35f6b1e
Note the bolded sentences (emphasis mine). I suspect that your device is running the latest AOSP netd code that has the fix (if the ROM is indeed based on AOSP 4.4.1/4.4.2), but the kernel may be missing the TCPMSS target. If you see an error when running this command as root, it probably means that kernel support is missing:
Code:
iptables -t mangle -A POSTROUTING -p tcp --tcp-flags SYN SYN -d 1.2.3.4 -j TCPMSS --clamp-mss-to-pmtu
Toward the bottom of the page on the original Android 4.4 MSS bug report I see a couple of reports from other Note 3 owners that the problem still isn't fixed for them, so it may be something particular to this device (such as the kernel configuration).
I do not see any evidence of IPv6 usage in your log, which rules out some of the known 4.4.2 VPN issues.
If this does turn out to be a kernel problem, you can try a custom kernel from XDA (assuming you can unlock your bootloader), or you could file a bug report with Samsung asking them to enable CONFIG_NETFILTER_XT_TARGET_TCPMSS=y in the next OTA update. From their end this is a simple, low-risk change.
cernekee;
Note the bolded sentences (emphasis mine). I suspect that your device is running the latest AOSP netd code that has the fix (if the ROM is indeed based on AOSP 4.4.1/4.4.2) said:
iptables -t mangle -A POSTROUTING -p tcp --tcp-flags SYN SYN -d 1.2.3.4 -j TCPMSS --clamp-mss-to-pmtu
[/code]
Toward the bottom of the page on the original Android 4.4 MSS bug report I see a couple of reports from other Note 3 owners that the problem still isn't fixed for them, so it may be something particular to this device (such as the kernel configuration).
I do not see any evidence of IPv6 usage in your log, which rules out some of the known 4.4.2 VPN issues.
If this does turn out to be a kernel problem, you can try a custom kernel from XDA (assuming you can unlock your bootloader), or you could file a bug report with Samsung asking them to enable CONFIG_NETFILTER_XT_TARGET_TCPMSS=y in the next OTA update. From their end this is a simple, low-risk change.
Click to expand...
Click to collapse
as you can see in the attachment I applied the code with no error message. so in this case I assume I have no problem with the kernel? right?
then what causes the problem? and what can I do in order to solve it?
msm88now said:
as you can see in the attachment I applied the code with no error message. so in this case I assume I have no problem with the kernel? right?
then what causes the problem? and what can I do in order to solve it?
Click to expand...
Click to collapse
Can you connect to the VPN, try to access a few "bad" sites, and then post the full output from:
Code:
su
iptables -t mangle -nxvL
cernekee said:
Can you connect to the VPN, try to access a few "bad" sites, and then post the full output from:
Click to expand...
Click to collapse
here is the output after some bad sites access, I also repeated the provisos code during an openconnect session. hope it will help us.
msm88now said:
here is the output after some bad sites access
Click to expand...
Click to collapse
Hmm, on my KitKat device I have an st_mangle_POSTROUTING chain which does the TCPMSS clamping:
Code:
Chain st_mangle_POSTROUTING (1 references)
pkts bytes target prot opt in out source destination
0 0 TCPMSS tcp -- * tun0 0.0.0.0/0 0.0.0.0/0 tcpflags: 0x06/0x02 TCPMSS clamp to PMTU
I did not see this in your output. Maybe Samsung is using an outdated version of netd.
Try running this command as root after bringing up the VPN and see if you are able to pass traffic with the bad sites:
Code:
iptables -t mangle -A POSTROUTING -p tcp -o tun0 --tcp-flags SYN,RST SYN -j TCPMSS --clamp-mss-to-pmtu
If not, post the new "iptables -t mangle -nxvL" output so we can look at the traffic counters.
Also can you attach your /system/bin/netd binary?
Thanks.
cernekee;
Try running this command as root after bringing up the VPN and see if you are able to pass traffic with the bad sites:
[code said:
iptables -t mangle -A POSTROUTING -p tcp -o tun0 --tcp-flags SYN,RST SYN -j TCPMSS --clamp-mss-to-pmtu
Click to expand...
Click to collapse
are kidding me!! it really worked. after I run the the code I tried to access all the bad sites and all of them worked!! but not as fast as my other mobil SG2. I noticed that it takes noticably much longer to access them. but still, It worked and It's fantastic!!
any ways, I rebooted my note3 to see if it will work again but it turned out it didn't! I need to re-enter the code again to make it work. now could you tell me what is my phones problem exactly? despite the re-entering issue I'm very happy that I finally can use internet on my note3 again thanks to you cernekee.
msm88now said:
any ways, I rebooted my note3 to see if it will work again but it turned out it didn't! I need to re-enter the code again to make it work. now could you tell me what is my phones problem exactly?
Click to expand...
Click to collapse
The ROM is supposed to add that rule automatically, but it doesn't.
If you attach your /system/bin/netd binary and output from "getprop" I'll try to figure out why.
cernekee said:
The ROM is supposed to add that rule automatically, but it doesn't.
If you attach your /system/bin/netd binary and output from "getprop" I'll try to figure out why.
Click to expand...
Click to collapse
here I attached them.
I posted a problem report on Samsung's support forum:
http://developer.samsung.com/forum/...&messageId=259244&listLines=15&startId=zzzzz~
Works like a charm with the lastest Slimkat on Nexus 4. Thanks a lot !
Just add a widget to one click connect from the launcher and it will be the best VPN apps that I've use.
Today I've a Tasker task to launch Anyconnect with uri and simulate touchs screen to automate my connection.
@ edit :
Is there a way to don't have the attached screen ?
Hi everyone,
What is this?
This is a DHCPv6 Client for Android.
Motivation
Google doesn't support DHCPv6. See: https://code.google.com/p/android/issues/detail?id=32621
This is an issue for a lot of people especially for corporations and universities because they need control over the IPv6 addresses they distribute.
I did some research and found out that Fairphone already has support for DHCPv6, they achieve this by implementing the wide-dhcpv6 client and added some own scripts around it.
This gave me the idea to play a little with this client. I did so and the result is this app.
Basically it is an implementation of Fairphone's DHCPv6 solution for every rooted Android phone and not just Fairphone.
Workflow
Broadcast Receiver for CONNECTIVITY_CHANGE (invoked when connectivity is changed)
Check if /system/bin/dhcp6c <interface> is running (this is the master process) if not then invoke it
Sending a signal with /system/bin/dhcp6ctl to the master process to get an IPv6 address (dhcp6ctl -C start interface <interface>)
Why is root required?
Root permissions are required for the DHCPv6 client to work because it binds to port 546.
Permissions
root - see above
access network and wifi state - catching network changes
internet - for checking if internet is available and getting a list of all interfaces available
billing - for donation
Get the app
Simply download it from the app store: Download from Google Play Store
Source Code
DHCPv6 Client for Android on GitHub
-realm_01
hostname/domain name support?
Installed this on my android TV media box, and it now connects to my DHCPv6 server as expected, and a lease is registered, however it does not supply a host name or domain name. The domain name is advertised by my router, and also supplied as option in DHCPv6 scope.
Are these an android problem, or the DHCPv6 client?
Almost working...
Hi !
Thanks for the app. Android really needs this. I'm trying to use it on Motorola XT1058 running Lollipop. I can see in the packet capture of my router (OpenWrt) that the DHCPv6 transaction is working and my router is giving out statefully assigned IPv6 addresses to my phone. Unfortunately, these addresses don't get assigned to wlan0 interface on Android. I'm still seeing only stateless addresses on wlan0. Any help would be appreciated.
Regards,
André
Thank you, as a system administrator it was crazy annoying to not be able to enforce a an IPv6 range for android devices
This app doesn't work until I adb shell into my device and run dhcp6c wlan0 as root manually.
Works on Pixel XL
Works fine on my Pixel XL with Android 7.1.
Thank you!
Hi, great job on this app. Wondering how you were able to override the Android DHCP software from trying to connect to networks and have it use the IPV6 info your client acquired?