[android] Monitor network activity in Android Phones

I would like to monitor network traffic of my Android Phone. I was thinking using tcpdump for Android, but I'm not sure if I have to cross-compile for the phone.

Another question is the following, If I want to monitor the trafic data for a certain application, there's any command for doing that?

You would need to root the phone and cross compile tcpdump or use someone else's already compiled version.

You might find it easier to do these experiments with the emulator, in which case you could do the monitoring from the hosting pc. If you must use a real device, another option would be to put it on a wifi network hanging off of a secondary interface on a linux box running tcpdump.

I don't know off the top of my head how you would go about filtering by a specific process. One suggestion I found in some quick googling is to use strace on the subject process instead of tcpdump on the system.

The common approach is to call "cat /proc/net/netstat" as described here:

Android network stats

For Android Phones(Without Root):- you can use this application tPacketCapture this will capture the network trafic for your device when you enable the capture. See this url for more details about network sniffing without rooting your device.

Once you have the file which is in .pcap format you can use this file and analyze the traffic using any traffic analyzer like Wireshark.

Also see this post for further ideas on Capturing mobile phone traffic on wireshark

If you are doing it from the emulator you can do it like this:

Run emulator -tcpdump emulator.cap -avd my_avd to write all the emulator's traffic to a local file on your PC and then open it in wireshark

There is a similar post that might help HERE

Packet Capture is the best tool to track network data on the android. DOesnot need any root access and easy to read and save the calls based on application. Check this out

The DDMS tool included in the Android SDK includes a tool for monitoring network traffic. It does not provide the kind of detail you get from tcpdump and similar low level tools, but it is still very useful.

Oficial documentation: http://developer.android.com/tools/debugging/ddms.html#network

Without root, you can use debug proxies like Charlesproxy&Co.

Try this application https://play.google.com/store/apps/details?id=app.greyshirts.sslcapture

We can view all networking communications .. even SSL encrypted communications.

Note: tcpdump requires root privileges, so you'll have to root your phone if not done already. Here's an ARM binary of tcpdump (this works for my Samsung Captivate). If you prefer to build your own binary, instructions are here (yes, you'd likely need to cross compile).

Also, check out Shark For Root (an Android packet capture tool based on tcpdump).

I don't believe tcpdump can monitor traffic by specific process ID. The strace method that Chris Stratton refers to seems like more effort than its worth. It would be simpler to monitor specific IPs and ports used by the target process. If that info isn't known, capture all traffic during a period of process activity and then sift through the resulting pcap with Wireshark.

Preconditions: adb and wireshark are installed on your computer and you have a rooted android device.

1. Download tcpdump to ~/Downloads
2. adb push ~/Downloads/tcpdump /sdcard/
3. adb shell
4. su root
5. mv /sdcard/tcpdump /data/local/
6. cd /data/local/
7. chmod +x tcpdump
8. ./tcpdump -vv -i any -s 0 -w /sdcard/dump.pcap
9. Ctrl+C once you've captured enough data.
10. exit
11. exit
12. adb pull /sdcard/dump.pcap ~/Downloads/

Now you can open the pcap file using Wireshark.

As for your question about monitoring specific processes, find the bundle id of your app, let's call it com.android.myapp

1. ps | grep com.android.myapp
2. copy the first number you see from the output. Let's call it 1234. If you see no output, you need to start the app.
3. Download strace to ~/Downloads and put into /data/local using the same way you did for tcpdump above.
4. cd /data/local
5. ./strace -p 1234 -f -e trace=network -o /sdcard/strace.txt

Now you can look at strace.txt for ip addresses, and filter your wireshark log for those IPs.