I am interested in deriving a list of active TCP/UDP network connections on an iOS 4.3 device. Basically, I'm looking for the same type of information one gets from issuing a "netstat -anp tcp" (or the same, but with udp) command under OS X Darwin.
I've searched Apple's iOS Developer Library (especially NSNetServices, CFNetServices, and the iOS Manual Pages) and the Internet, but with no good results. Yet, there is an iOS Netstat app (see http://itunes.apple.com/us/app/netstat/id400071873?mt=8&ign-mpt=uo%3D2) out there, so it appears possible.
Thanks in advance for any useful pointers/suggestions/thoughts.
I believe I have now answered my own question. Thought I had taken a close enough look at the sysctl() library function, but I hadn't! For example, the following will yield information about the current TCP connections:
sysctlbyname("net.inet.tcp.pcblist", ...)
To get information about UDP connection, simply use a different Management Information Base (MIB) name: net.inet.udp.pcblist.
For convenience, here's a link to the appropriate iOS man page:
http://developer.apple.com/library/ios/#documentation/System/Conceptual/ManPages_iPhoneOS/man3/sysctlbyname.3.html
Related
I need to slow down (simulate bad) internet connection, I found some documentation where it was achieved by "ipfw pipe" command , the thing is that in latest MAC OS versions , ipfw was deprecated (and removed)...
I was wondering if there are any alternative to the ipfw API ?
Does anyone know how latest Network Link Conditioner achieves it?
The original previous way which enabled to slow down an internet connection :
sudo ipfw pipe 1 config bw 56Kbit/s delay 200 plr 0.2
and to clear the pipe :
sudo ipfw delete 1
Thanks.
I don't know much about Mac OS (I use Linux myself), but I'll give this a shot.
A bunch of digging established that ipfw seems unavailable, as you say.
I was also unable to find a way to use the Network Link Conditioner from the command line. Everything should be usable from the command line, so that's stupid.
One work around would be to try to access the NLC from within AppleScript. The following will get you started on toggling the NLC:
property thePane : "com.apple.Network-Link-Conditioner"
tell application "System Preferences"
activate
set the current pane to pane id thePane
--delay 2
end tell
---
tell application "System Events"
tell application process "System Preferences"
try
click ((checkboxes of window "Network Link Conditioner") whose description is "enable switch")
on error
click ((checkboxes of window "Network Link Conditioner") whose description is "enable switch")
end try
end tell
end tell
I think that you can run a script from the terminal with osascript <SCRIPT>.
As an alternative, Charles Proxy is a pay-to-use program that can be used to perform throttling, provided you can convince the software you are testing to connect to the proxy's port rather than directly to the internet. Maybe there are free proxy solutions out there somewhere?
Perhaps Squid would work in that regard. SquidMan seems to be an easy-ish way to install it for Mac. It looks as though DelayPools and or Client Bandwidth Limits might be useful for simulating a low speed connection, though I can't find evidence of people having used them for such.
I found several solutions that might work. They come from some old threads, but they might help:
How to simulate slow internet connections on the mac
Apple has made a very handy official tool to slow down the network connections on you Mac for testing purposes.
The Network Link Conditioner preference is a free download from within Xcode (for Lion and later OS). Additionally, iOS has similar function accessible from within Xcode and iOS 6 or later.
How do I simulate a bad Wi-Fi connection on my iPad?
There are a few ways you can do this, depending on your situation:
Move further away from your router. While this may seem a bit obvious, I realize that it isn't always possible while testing/debugging (for example, if you are working on a desktop computer).
Put aluminum foil around the router and/or antenna. This will (partially) block some or all of the radio signals by creating a makeshift Faraday cage. The results you get will depend on the strength of your router signal, distance from the router, and other environmental factors.
Set your router's wireless signal power to a lower setting. The method for doing this is different for each router, so you will have to look at the user guide for instructions on how to do this.
Slow down internet for iOS simulator
You can set the network to slow characteristic by testing on devices. Go to Settings -> Developer Settings -> Network Link Conditioner -> Enable. This is for iPhone/iPad running iOS 6
I don't know if the last one you can still do.
I've used many methods in the past for slowing down network connections, among them:
performing a parallel download of some massive Linux ISO file;
physically pulling out the Ethernet cable (at one point, I actually toyed with the idea of building a push-button device that would sit between two cat5 cables and do this without having to physically disconnect the whole cable).
using ifconfig eth0 down ; sleep 1 ; ifconfig eth0 up.
Hopefully one or more of those methods will help.
If you're looking to slow down your network connection because you're doing testing/profiling work, one option is to get a specific device that can create network latency/noise.
For example Apposite Tech's mini2 WAN emulator allows you to change values for bandwidth and packet loss. You can roll your own device too using something like: http://wanem.sourceforge.net/ . It just depends on your needs, time and budget.
Is it possible to access my Cisco router details like Name,Model,IP Address,Connection status etc from my iOS mobile.
I'm even ready to write small mobile app in iOS to get all router details.
Since I have just started learning in iOS, don't know if any library already exists for above task.
If my router does not work or gets hang.. I even want to try for restart of router using my mobile.
If example code exist, it will be very useful.
Like Cisco already has andriod and iOS app for same above function but dont want to use this app and want to write my own app with limited features only.
(http://www.addictivetips.com/mobile/cisco-connect-express-manage-router-settings-remotely-android-ios/)
Thanks,
Accessing network gear is best done by using SNMP. Cisco has extremely rich management/monitoring capabilities via SNMP and all of their MIBs are publicly available here.
Almost all Cisco gear supports the SNMPv2-SMI MIB (the 1.3.6.1.2.1 OID) so querying things like sysName, sysLocation, sysContact, sysDescription, sysUpTime should be very easy. This MIB even supports tables for listing all the interfaces and IP addresses and has a whole lot of other things that might be of interest to you.
If you have SNMP write access on the device then you can even make config changes and perform management functions like rebooting or bringing an interface up/down.
There are a few SNMP libraries for ObjectiveC and I think Net-SNMP is the most popular (It's not .net even though the title suggests that).
If you are new to SNMP then I suggest starting simple by querying easy objects like 1.3.6.1.2.1.1.5 (sysName) and 1.3.6.1.2.1.1.6 (sysLocation) before trying to jump into tables like 1.3.6.1.2.1.2.2 (ifTable)
Remember, you don't have to stick with the standard MIBs you can download all of the custom ones that are particular to your device which will give you incredible amounts of flexibility.
You could use a screen-scraping technique to telnet or ssh to the Cisco device and parse the "show version" output. This will give you some of the information you need. For others, like IP addresses, you can use "show ip interface brief", "show cdp neighbors" etc. as you need.
Keep security in mind: make sure that telnet/ssh credentials are adequately protected in your app's settings, and try to restrict your commands to those that do not need privileged access on the Cisco device.
Be aware that Cisco devices have a small pool of available VTYs, and every telnet/ssh access from your app will use up one VTY. So if you have for example 30 guys wanting to use the access the device simultaneously from their apps, some of those instances are not going to get access to the device.
If this is a concern, SNMP is a better and more scalable option as suggested by previous answer. Make sure that you (a) have a read-only community string configured on the device, and (b) use only the ro community string from the app.
I have a customer who has a device that has its own builtin wifi hot spot and he would like to connect it to an iPad 4G vie wifi and forward data at the same time through the cellular connection. Is this supported in IOS and if so can you point me to the appropriate documentation. Any suggestions are appreciated.
Jim
Comparing to Android, iOS supports simultaneous work of multiple network adapters. It's necessary to write C code working with BSD sockets, doing enum, bind, and handling network interface changes.
By the way, it's ideologically very important to continue using that native BSD functionality in C/C++, otherwise, who knows, Apple may in 5-10 years remove support for BSD sockets completely :-)
Some C examples of how to do that you can find here:
https://gist.github.com/avesus/fdb465b60a4f5204845c
I've been looking for this answer myself and eventually found a solution here:
https://apple.stackexchange.com/questions/62870/how-do-i-tell-an-ios-device-theres-no-internet-connection-on-the-wifi
The solution does not involve any code but instead changing the settings on your iPad. Change
the settings for the Wi-Fi connection to Static instead of DHCP. In the Static settings leave
the Router field EMPTY. What I did was write down the IP Address, Subnet Mask, and DNS values
that were being used by DHCP and then just left the Router field blank. I have found a couple
of other posts that suggest entering 0 or 0.0.0.0 but leaving it blank was what made it work for me.
To better clarify my generic question:
I have gotten the Android emulator to work by running a full "make full-eng" build, as per the Google documentation. However, I wanted to debug it, so once I ran the emulator, and called "$ adb shell dmesg" and routed that to an output text file, I found a couple of strange lines:
...
<4>goldfish_new_pdev goldfish_interrupt_controller at ff000000 irq -1
<4>goldfish_new_pdev goldfish_device_bus at ff001000 irq 1
<4>goldfish_new_pdev goldfish_timer at ff003000 irq 3
<4>goldfish_new_pdev goldfish_rtc at ff01000
So when you run the Android full build, it gives you Goldfish as the system image? I want to know if it's testing the things I want for Galaxy Nexus. The kernel was a modified maguro kernel (omap project) for Galaxy Nexus, that I put into the build tree. But the platform I want to be testing is IceCreamSandwich. Is the emulator testing this platform? (b/c the output in this log is leading me to believe it isn't) Or is the emulator testing a "generic" image?
Also, an important further question: I modified the kernel's "socket.h" file, to override the INET protocol with an undefined protocol (FINS). In theory the phone should boot up, but NO internet access. Does the phone emulator care what you do to the internet protocols? Does it use your host computer's networking capabilities?
One further follow-up: What processes/system-services/events (that are involved in booting to a stable state) of the phone DEPEND on the internet protocols of the traditional underlying network stack? (protocols being defined to set up the network sockets)
At the time I wrote the question I did not understand a few things and think I've learned a little while messing with the emulator at the "kernel level". First of all, the emulator tests the "goldfish kernel" (Linux version 2.6.29, with ARM architecture) of a "generic" phone brand. It's almost as if the emulator is a type of phone in of itself, and you cannot mix these image kernels. For example, I tried building a Nexus S crespo phone image with goldfish kernel (so in other words, no crespo kernel) and the phone just "hangs" at the Google splash-screen (at least it's not a boot-loop).
My research (FINS) worked on this emulator, but did not work on any of the 3 platforms supported on actual hardware: Nexus S, Galaxy Nexus, and Motorola Xoom. I am not sure why, given Google does not seems to give users the ability to debug at the lowest level of a phone (I'm sure the actual developers use such kinds of tools in building these phones/testing them). This leads to one major issue which answers my last follow-up: The Android Debug Bridge depends upon INET protocol. My emulator boots up successfully and runs as I want (no internet, b/c there is no INET), but these actual phones do NOT. My hypothesis is that: If INET is overridden with a protocol that is empty (in this case, that would be FINS, which intends to deal with INET at the userspace level, but this appears to be too late for the phone system to be satisfied), the ADB daemon (classified as a type of system service perhaps) cannot work/be connected to and Android hardware will crash because of this. The emulator I believe is more flexible than a real phone, as the hardware is perhaps virtually represented and does not have the same limitations as physical hardware does.
You can consult my wiki/documentation (part of my research team's larger site) of my struggle with the Android phone boot process for more details and my various attempts: http://finsframework.org/mediawiki/index.php/Alexander_G._Ororbia_II
If anyone ever figures out how to get a working boot log from a Nexus S, Galaxy Nexus, or Motorola Xoom that gets stuck in a "boot-loop" (without ADB), please let let me know, as I will be working on this problem for a while to come (and I will update my other Stack Overflow-Android questions to reflect this correction). Any corrections to my understanding would also be appreciated.
NOTE: This answer is editable, as I still think there is some way of getting the phone to produce boot logs on the host machine without the ADB daemon.
I've been crashing around on the netfilter/iptables home page as well as beseeching The Google, but no luck so far.
I have a Rails application which needs to control packet filtering for its Linux host. It could do this by just dumping rules into /etc/sysconfig/iptables and bouncing the iptables startup script, of course. But it would be sweeter if it could just seamlessly make the calls via an API.
The app's requirements are actually very very simple; it only needs to add and delete ACCEPT rules for a given source IP address to a given TCP port on the server, to control access to that service.
I found references to a ruby-iptables project, but that apparently went moribund some years ago.
If I have to resort to raw getsocketopt() calls and the like, I'll just do the text-file-and-restart approach, which will offend my Slickness Sensor but make my customer smile, because he likes working software better than really elegant software that will work Very Soon Now.
If you search for "ruby netfilter" there's more to be found. NetFilter (http://netfilter.org/) is the underlying framework behind iptables.
http://rubyipq.rubyforge.org/ (traffic shaping)
https://github.com/johnl/netfilter.rb (DSL)
http://rubyforge.org/projects/iptcext/ (IPTC library interface)
The last is most like what you want, but while there's code, there doesn't seem to be a real release.