Chapter 3203: Forged QR code

On a street corner, the black man turned and said, "Will you avoid searchlights?" "Understand a little." Lin Rui nodded.
The black man whispered, "Then come with me, remember that the speed of the searchlight is about a few seconds slower than the speed of our actions, count down to five numbers, follow the light, and the distance to the light circle is ten meters away , You can guarantee safety."
In fact, there is no need for him to explain more. Lin Rui and others are experts in this area, and it is not difficult for them to avoid searchlights. But they were quite surprised by the black man's skill, and they could see that the black man was well-trained, which is rare in the resistance army.
After all, most of the rebels were militias, even civilians. There are not many people with his agility. The black man took Lin Rui and the others to a nearby building and saw that no one was following him. The black man was relieved. "Okay, it's safe here."
Lin Rui turned to look around, and whispered, "Where is this?"
"An old house, the owner was taken away by government forces last year. This place has been in an uninhabited state." The black man whispered, "This place is not very patrolled, and it is safe during the day. But you'd better not be too close to the window, so as not to be noticed. There is a staircase leading to the attic, where you can see the surrounding situation. A dish antenna can be set up there, and the communication signal is good. There are also food and sleeping bags on it, which can be used for you Use it for a few days."
Lin Rui nodded, "What about the others?"
"Others are at the contact point. I can't take you there. For safety reasons, we can only provide so much help." The black man whispered. "My task is to bring you here. I won't take care of the others. I'm sorry, but I have to go back. If I don't go back at dawn, others will be worried."
Lin Rui nodded, "That's okay." The black man nodded, turned around, and closed the door.
"Boss, it is indeed safe here. I checked the surrounding area, and there is no sign of government activities." Scarface walked over and replied, "The nearest checkpoint is also 1.6 kilometers away."
Lin Rui breathed a sigh of relief, and was about to speak, Sausage ran over and said, "The intelligence team has come to the news, and they have received detailed information from an Olumi Federation officer. The day after tomorrow, Red Baron will attend a meeting, this meeting. It's about the anti-terrorism operation in Libya. Most of the secret society executives, including the Red Baron, will attend."
"Great, this proves that Aladdin's intelligence is correct. We finally caught up." Lin Rui nodded. "Any other information?"
"Yes, Cobain requires video communication." Sausage nodded.
"Come in. It may be that the QR codes have news." Lin Rui nodded. Sausage took out the tactical computer and placed it on the table. Cobain's image emerged. He frowned slightly, "It seems dark in your place."
"Sorry, there is a curfew and light control in the city." Lin Rui whispered, "We don't want to attract attention either. Let's talk about it, what's going on with you?"
Cobain nodded, "The QR code is also known as QRCode, and the full name of QR is QuickResponse. It is an extremely popular encoding method on mobile devices in recent years. It can store more information and express more information than traditional BarCode barcodes. Multiple data types.
The two-dimensional code uses a certain geometric figure to record data symbol information in a black and white pattern distributed on a plane according to a certain rule; in the code preparation, the concept of 0, 1 bit stream that constitutes the internal logic of the computer is cleverly used. Several geometric shapes corresponding to the binary system are used to represent text and numerical information, which can be automatically read by image input equipment or photoelectric scanning equipment to realize automatic information processing.
It has some commonalities of barcode technology: each code system has its own specific character set; each character occupies a certain width; it has certain verification functions, etc. At the same time, it also has the function of automatically identifying different lines of information, and processing graphics rotation change points. This is not complicated. Based on the video information you provided, I analyzed the encoding rules of these barcodes. Can basically determine the rules used in these codes. "
"That is to say, you can imitate this type of code to forge information?" Lin Rui asked.
"This is okay, but it can only forge information. Once it doesn't match the real information in the other party's system, it will soon reveal itself." Cobain shook his head, "So this method does not help you to get in safely. ."
"Damn, I forgot these." Lin Rui shook his head, "That means these QR codes are only used to verify identities. Even if we pretend to be this QR code, we can't get in. Because even the two on our side The Dimension Code complies with the rules, but there is no corresponding information on the enemy side."
"Yes. But in this QR code, I can do something special, let the computer delay the identification and verification process for tens of seconds, at least after you get in, after tens of seconds, Set off an alarm." Cobain replied.
"Isn't this more a snare? Wait for someone to enter, and then trigger the alarm." Sergey shook his head, "make it clear that it is for someone to catch alive."
"No, that's not the case. I can do tricks on the QR code, so when going through the security check, the alarm will be triggered for a while. You just need to go through the security check when there are many people. Then the alarm will fall behind you. After at least five or six people. The guards will only control the person they think triggered the alarm on the spot, and when they return to check the computer data, they can find out that the alarm was triggered by you. This process may last several minutes, which means , When you were actually discovered, it was already a few minutes later." Cobain shook his head. "This is the ultimate we can do."
"That is to say, we use a fake QR code to enter, and it will be discovered in a few minutes. It is enough for us to make a time difference." Lin Rui nodded.
"I'm sorry, it's not you, it can only be one person. We can delay the recognition time by doing things on the QR code, but it cannot avoid being discovered. If more than one of you enters, the system will detect the abnormal speed Improved a lot. It may only be a few seconds, which is enough to meet the time required for you to leave. In other words, if you two use a forged QR code at the same time, you will be discovered immediately." Cobain replied.
"What's this, you spent so much time, you just told us that only a few tens of seconds will be discovered, and only one person can get in." Sergey said in amazement.