Saturday, December 29, 2012

The smallest guide to encryption!! Encryption for starters.


 http://static.ddmcdn.com/gif/encryption-1.jpg

Most people mistake this word as "Only meant for hackers and programmers" but its only the name that is complicated. In fact, understanding how it works is quite simple!

Simplified definition: Encryption can be defined as the process of conversion of some information in such a way that it can be understood/decoded/rendered only by the people who are authorized to do it.

So if you want to send some data to your friend and you don't want anyone to be able to access it even if they confiscate/eavesdrop the piece of data, you should probably encrypt it. The unreadable copy of data can also be called a ciphertext. So how does this actually work??
There are millions of algorithms (ways) in which you can encrypt/decrypt data. It is used extensively by governments, military etc. to exchange information. But deep inside, it's a sophisticated procedure. A single slip-up in any part of the encryption can be used as an opening or attacking point for hackers. Hackers have several ways of undoing the encryption so there are always new algorithms and cracking methods coming up.
In most cases there is a password to decrypt the data which is known only by the ones who are authorized.

Here are a few ways (not all) in which a hacker can undo the encryption or gain access to the unencrypted data:

1. By infecting the file with a trojan horse or a virus before it is even encrypted:
 This sounds crazy!! Some hackers first send a hidden virus or a trojan horse to the victim's system. The victim never knows that his system is infected. The virus is of such a kind that it sends the encryption/decryption passwords to the hacker or he gets a better idea on how it can be broken. Genius!!

2. Brute force attacks:
This attack sounds simple but its not so. The idea is to keep guessing the password in every possible way until you find the correct one. This process might take hours, days or even years with little chance of completion. The resources and the time required to correctly figure out the password grows "exponentially" with it's length and difficulty. That is why we are asked to keep long and difficult passwords which contain numbers and symbols while registering on some websites!

3.Cold boot attack:
This attack is possible if the attacker has physical access to the victim's computer. The hacker "cold-boots" the victim's computer in the middle of encryption process without completely shutting it down (e.g the reset button). So in any lightweight OS when system is restarted suddenly, the details of running processes are dumped to a file whose location is already known to the attacker. This method requires a deep understanding of a computer's internal processes and is not always successful.

There are several other methods such as keylogging, cryptanalysis by rainbow tables and countless more.

So coming back on talking about encryption, there are various software and hardware which encrypt data in a chosen format and some also help in cracking it!! Here are some of them:

Encryption/Decryption software: TrueCrypt, Symantec Endpoint Encryption, BitLocker Drive Encryption, BestCrypt

Cryptanalysis (cracking) software: Aircrack-ng, Ophcrack, Cain and Abel

Hope this article was helpful.

Saturday, September 29, 2012

How to fix a bricked/bootlooped phone???

If your phone keeps rebooting
If you've flashed a ROM and your phone won't boot into the home screen, it's probably because you forgot to wipe your data and/or cache. It's trying to boot into the ROM, but some leftover data from your last ROM is causing it to error out, and it'll reboot itself over and over again. If your phone's eating a big bowl of boot loops, your first course of action should be to wipe its data and cache, which you can do from recovery mode. This method assumes you're using ClockworkMod Recovery, like the majority of Android users, but if your particular phone uses a different third-party recovery (like AmonRA), you should still be able to find these options in the interface. They might just be in a different place. To wipe your data and cache:

1.Power down your phone. Turn it back on and boot into Recovery mode. This is a bit different for every phone, so you'll have to Google how to do it for your specific model. Usually it involves holding down another button, like Volume Down, as you turn your phone on. HTC phones will have to then select "Recovery" from a menu, while other phones will boot directly into ClockworkMod. You'll know you're in ClockworkMod by the words "ClockworkMod Recovery" at the top of the screen.
2.Use your volume keys to navigate the menus, and your power button to select menu items. Scroll down to Advanced, and choose "Wipe Dalvik Cache". When that's finished, go back to the main screen and choose "Wipe Cache Partition". Lastly, head to "Wipe Data/Factory Reset". This will delete all your settings and apps, but you should still be using the correct ROM.
3.Reboot your phone.

If Your Phone Boots Straight Into Recovery: Flash a New ROM
If, when you boot up your phone, it goes straight into ClockworkMod, then there's likely an issue with the ROM you flashed. Note that some ROMs boot into recovery mode automatically after flashing, so reboot your phone once from recovery mode to make sure you're having a problem. HTC users: if you boot up your phone, it might go straight into the bootloader—check to see whether you can choose "Recovery" from the list before continuing to the next step. HTC phones usually don't boot straight into recovery.

In this case, you'll want to reflash the ROM from scratch. Try again with the ROM that messed up your phone, if you so choose, but if that doesn't work, try an entirely different ROM. The best way to do this is to download a ROM from somewhere on the net and putting it on your SD card. You'll need to take the SD card out of your phone, and you'll need an SD card reader that you can plug into your computer. Here's how it works:

Plug the SD card into your computer. Drag the ROM's ZIP file to your SD card, and wait for it to copy.
When it's done copying, eject the SD card and put it back in your phone. Reboot into Recovery mode. This is a bit different for every phone, so you'll have to Google how to do it for your specific model. Usually it involves holding down another button, like Volume Down, as you turn your phone on. HTC phones will have to then select "Recovery" from a menu, while other phones will boot directly into ClockworkMod. You'll know you're in ClockworkMod by the words "ClockworkMod Recovery" at the top of the screen.
Use your volume keys to navigate the menus, and your power button to select menu items. Scroll down to "Install ZIP From SD Card" and navigate to the ZIP file you just copied over. Give it time to flash the ROM.
When it's done, reboot your phone.
Hopefully, your phone should successfully boot into the new ROM. From there, you can probably assume that the previous ROM that messed up your phone isn't going to work, and you'll have to find another ROM for now—or find another copy of that ROM that isn't corrupted. Remember to make backups of your working ROMs so you don't lose all your data!
                        

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