How to properly recover data from an Android phone?

Abstract: Many people think that data recovery is just scanning with tools. This idea is very wrong. If you want to do something well, you must not just repeat the inherent actions mechanically, you must add personal thinking. For example, data recovery for Android phones, do you really know how? 0×00 Background introduction Many people have the experience of deleting data by mistake when using their mobile phones. For example, after breaking up with their girlfriend, they deleted the video data they played together before, but they reunited after a few days. One day, the girlfriend wanted to marry him. You're reminiscing about a sweet moment together, and it's embarrassing to not be able to come up with a photo or video.

Many people think that data recovery is just scanning with a tool. This idea is very wrong. If you want to do something well, you must not just repeat the inherent actions mechanically, you must add personal thinking. For example, data recovery for Android phones, do you really know how?



0×00 Background introduction


Many people have the experience of mistakenly deleting data when using their mobile phones. For example, after breaking up with their girlfriend, they deleted the video data they played together before, but they reunited after a few days. One day, the girlfriend wanted to date him. You're reminiscing about a sweet moment together, and it's embarrassing to not be able to come up with a photo or video. In order to avoid this kind of tragedy between people (Xi) (Wen) (Le) drama (Jian), it is necessary to master data recovery technology.



Traditional data recovery can often be done with the help of software, such as Easy Recovery, Recuva and the like. However, this kind of software is often powerless for new Android phones, because since a few years ago, most mobile phone manufacturers have replaced the large-capacity USB storage mode with the "media device" MTP mode, and traditional data recovery software cannot directly respond to MTP. Mode loaded mobile phone storage space for data recovery, as shown in the figure.



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Therefore, it is necessary to study the data recovery method suitable for the current Android system mobile phone. This article mainly discusses the data recovery of the internal storage space of the mobile phone. The data recovery of the mobile phone TF card can be completed by traditional means, which will not be discussed in this article. .



At present, there are three common methods of mobile phone data recovery:

The first method:


Physically disassemble the chip for data recovery. After disassembling and taking out the memory chip, the data of the chip is read with the help of hardware tools to recover the data. The advantage of this method is that no new data is written to the memory chip, and the original state of the data can be better protected. The disadvantages are also obvious. This method requires higher tools and hands-on ability. If the mobile phone and chip are at risk of being scrapped, it is difficult for ordinary users to complete such operations independently.

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The second method:


data recovery with the help of third-party tools installed on the PC. At present, the well-known Android data recovery tools on the Internet mainly include Wondershare Dr.Fone, Tenorshare-android-data-recovery, 7-Data Recovery Suite and other software, but the common problem of such software is that it is often unable to establish a connection with the mobile phone , or it prompts failure when scanning after connection, which may be due to the high degree of customization of the Android series mobile phone systems, and each mobile phone manufacturer has made more or less modifications to the Android system, resulting in unsatisfactory actual results. I believe many A friend also encountered a similar problem when using this kind of software.

Third method:


Data recovery is carried out with the help of the Android APP installed on the mobile phone. Since the APP runs directly on the mobile phone, there is no problem that the software fails to connect with the mobile phone in the second method. The recovery effect of this type of software largely depends on the strength of the data recovery algorithm used by the software developer. . There are many such softwares. Taking a digital cleaning master as an example, the privacy shredding function of a digital cleaning master can scan some types of files deleted by users before, and can indeed restore such files. But there are also many disadvantages, mainly in four points: First, the types of files that can be recovered are limited, mainly for photos, text messages, call records, etc.; cumbersome; third, the data recovery algorithm is not strong enough, and there is a big gap compared with traditional data recovery tools such as R-Studio and EasyRecovery; fourth, the data can only be restored to the internal storage space of the mobile phone, and cannot be restored to the SD card, so the mobile phone The original data is at risk of being overwritten by the newly restored data. Of course, these shortcomings may be related to the positioning of this software as privacy smashing rather than privacy recovery. These shortcomings also exist in many similar software, especially in terms of data recovery capabilities. Many software are too weak in this regard, and thirdly This method is also unsatisfactory due to the existence of many drawbacks.

0×01 Correct posture to restore Android phone data


So is there a more ideal data recovery method? The answer is yes. In fact, the biggest problem with the above methods is that this kind of software is either not usable at all, or the resilience is too weak. If you can use the powerful algorithms of traditional data recovery tools, then such problems will naturally be solved. The following introduces a solution that can largely solve the bottleneck in the above methods. This article takes Nubia Z9 Max NX510J as an example, and the steps are more detailed in order to take care of readers of different levels as much as possible.



The first step is to root the phone. Before rooting, you need to enter the developer mode and turn on the USB debugging mode. This is the most basic requirement. How to root is related to the model of the mobile phone. If you really can't, ask an IT expert of the opposite sex to help you.



The second step is to install BusyBox in the phone. It is recommended to download from Google official, bring your own ladder, the tools used in the article will be provided at the end, lazy people will pick it up. The path can be selected when BusyBox is installed, assuming it is installed in [/system/bin/busybox].



The third step is to connect the phone to the computer. After connecting, you need to install the corresponding driver, which can be installed with tools such as pea pods. In addition, you need to prepare adb debugging tools (adb.exe and other files), which can be downloaded from the Android SDK official website, and are generally provided in the Root toolkit.



The fourth step, install the 32-bit version of Cygwin [C:\cygwin] on the computer, and download nc.exe and pv.exe, and combine these two files with the previously prepared adb.exe, AdbWinUsbApi.dll, AdbWinUsbApi.dll Copy to [C:\cygwin\bin\] directory.



The fifth step, run [C:\cygwin\Cygwin.bat], enter the commands in the following figure in turn, keep the window open after entering:



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adb forward tcp:5555 tcp:5555

adb shell

su

/system /bin/busybox nc -l -p 5555 -e /system/bin/busybox dd if=/dev/block/mmcblk0

Step 6, run it again [C:\cygwin\Cygwin.bat] to open another window, followed by Enter the following command:

adb forward tcp:5555 tcp:5555

cd /

nc 127.0.0.1 5555 | pv -i 0.5 > mmcblk0.raw

At this time, the progress shown in the figure should appear on the window

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After waiting patiently for completion, the mmcblk0.raw file will appear in the [C:\cygwin] directory, and the file size is equal to the size of the internal storage space of the mobile phone. It is the image file of the internal storage space of the phone.

The seventh step is to open a traditional data recovery tool. Since the raw file is in the linux file system format, software that supports this type of system is required. After the actual use test, it is found that both R-Studio and Easy Recovery can better identify this type of data. The file format, I prefer R-Studio, so take this software as an example. Load the mmcblk0.raw image just generated, as shown.

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scans the userdata part of the image, after scanning, you can find all kinds of data that have been deleted by mistake, and the girlfriend is finally saved :)

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Using this method, you can make full use of the existing mature The recovery technology of data recovery software greatly improves the success rate of Android phone data recovery. The actual test found that the number of photos recovered by this method far exceeds the photos recovered by various mobile phone data recovery software on the market. Some people abroad have written similar tutorials, but maybe because they are not familiar with data recovery software, they have done a lot of superfluous processing after extracting the image, such as using VhdTool.exe to perform various post-processing on the image, which not only increases the complexity of the steps , may also be misleading.



0×02 More Thoughts


The core of this article is to extract the Android phone image. There are many things that can be done after extracting the image. For example, by analyzing wpa_supplicant.conf, you can find out where someone frequents. From this article, we can see how big the risk is if the obsolete mobile phones simply delete some sensitive files and then hand them over to some third-party recycling agencies. How do you think there are so many small videos on the Internet? If you lack the basic protection awareness of mobile phone information security, you will have to bear the possible consequences, some of which may be serious enough to pay a high price.


0×03 Reference


http://forum.xda-developers.com/galaxy-nexus/general/guide-internal-memory-data-recovery-yes-t1994705



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The original release time is: 2016-02-04




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