Sapphire case

57.

"God... I actually forgot such a basic combination principle..." Luke frowned, took two steps back and bumped into his seat, sat down, and picked up the draft paper, "Then it's very simple, We can directly equip five spare rotors, randomly select three or even four to use when sending letters, we can completely reorganize the keyboard and wiring board... My God, this is simply unhackable!"

He changed the wires on the wiring board from six to ten. The possibility of the change made his eyes flush with excitement. For a long time, he found that no one had made a sound beside him. !what are you thinking about?"

Gu Sheng was holding two books at that time, propping his cheek with one hand, the orange light of sunset fell into the window, taking notes with his eyelashes drooping, as if he didn't hear him speak.Luke sighed, put the ink bottle on the draft, got up and walked over, reached out and tapped on the one-foot-high book next to him: "Hey."

The young man's eyes froze, and he raised his eyes in a daze. Luke couldn't stand his eyes at this time, because it was so different from his usual.

Luke can't deny that Gu Sheng is a very nice person, humble and polite, gentle and easy-going, he is different from most of the classmates he has come into contact with - a genius who thinks highly of himself is often proud, even Luke himself has to admit that he Most of the students who will associate with him have the common faults of geniuses, which come from a clear understanding of their own talents, and their life has been smooth and smooth, and they have received countless praises and praises along the way.

Gu Sheng is very different. As he himself said, he may not like mathematics as much as Luke and others, and he is not as talented in it as they are. Compared with those geniuses, he is just an ordinary learner. The student was not infected with the habit of flamboyance. Except for the group discussions that he had to participate in before, this person hardly participated in any activities. According to Luke's observation, his relationship with other students was also very distant.

At first, Luke thought it was because he was Asian, such as language or xenophobic problems, but in fact Gu Sheng was very good at English, because his grades were quite outstanding, and his classmates generally had a good impression of him, probably pure and simple. It's just that the personality is not enthusiastic, pure indifference, it is similar to everyone.

It is very rare for him to look a little dazed, probably because his eyes are beautiful and energetic, and it makes people feel very amiable when he is stunned occasionally.

Gu Sheng pressed the corners of his eyes, blinked, and pointed to the book in his hand: "...I'm reading the two monographs you gave me this morning. What's the matter, are you finished?"

Before Luke could answer, Gu Sheng took out a piece of paper and patted the table: "Come on, sit down, I have a few questions, I don't want to disturb you because of your hard work."

"Damn?... If you don't listen, I won't listen! I've been thinking about the algorithm for a day, and I'm exhausted. Are you a perpetual motion machine?" Luke reached out and wiped his face vigorously, "I don't even have to eat ! What kind of living conditions are these for overseas talents! I'm going to eat, goodbye!"

"Lunch has been delivered, and we haven't been out yet. Considering you, an 'overseas talent', we even delivered afternoon tea." Gu Sheng pointed to the opposite table, "I didn't want to disturb you, so I asked them to leave it at the door."

"Cough!" The overseas talent held up his glass and choked on the water, "Gu Sheng, do you mean to let me go! Couldn't the sun rise tomorrow!"

Gu Sheng laughed, put down his book and stood up, and put his shoulders on him: "Come on, young man, you have to know that what you are doing now is deciding whether the sun will rise tomorrow, and whether we have a chance to see tomorrow." the sun."

Luke let out a howl of "Aw".

"You ask, I'll drink some milk tea," Luke slid onto the table, took a sip from the cup, "Mmm! It's delicious, oh God, I'm hungry after smelling it."

"..." Gu Sheng couldn't laugh or cry, and tried to change the subject, "There is a very serious problem. I was taken away by you in the morning and I didn't notice it. The basic language of your cipher machine is the alphabetic writing system, which is a big problem. The problem is that the Chinese code has been unable to take a step closer in the horizontal and vertical codes and the addition and subtraction codes. The biggest obstacle is the characteristics of pictographs. What are you going to use to solve this problem? Replace the 26-style keyboard with horizontal and straight codes?"

"It's okay," Luke said sternly, "Oh, but at first I thought of using Wade's style, pinyin, based on the Latin alphabet."

"Pinyin?" Gu Sheng shook his head, "Have you communicated with a Chinese linguist at a school? What about the tones of Chinese characters? How about making a keyboard for tones?"

"No! This is the first time I've told you this idea, how could I go to a linguist." Luke put three cookies together and put them in his mouth, and said vaguely, "I think it's okay. Come on, think about it again?"

"Either add a tone to each final, or make another tone, but I think there is a huge problem with both methods, that is, the same pronunciation and different words." Gu Sheng asked him, "How much Chinese have you learned?" ? Do you know this?"

"I... don't really... know... right?" Luke swallowed the cookie, looked at Gu Sheng and said.

"..."

"Damn it! I don't know! I just remember who told me that Chinese characters are composed of strokes. I thought strokes are the variants of 26 letters!"

"Variant size, variant..." Gu Sheng flipped out a unified dictionary for him from the table next to him, and threw it beside him, "Radicals...these are the most basic Chinese characters."

"Oh, my god..." Luke glanced at it and wailed in despair, "Is this idea doomed to be put into use, no! I want to sell it to my motherland at a high price. ..."

Gu Sheng pressed his temples with a headache.

"Since you don't have a better idea, then I'll replace it with horizontal and straight codes. The basic idea is to replace Chinese characters with numbers, and then use a cipher machine to re-encrypt." Gu Sheng nodded and scratched on the paper, "Also Yes, how many deciphering solutions have you considered? Except for the almost impossible brute force deciphering."

"I haven't thought about it yet, but I have some ideas in the design process. What do you say?" Luke asked.

Gu Sheng was silent for a while, Luke questioned with suspicious eyes, seeing Gu Sheng slightly shook his head: "Unless you give me a prototype machine."

"Haha." Luke laughed shortly, jumped off the table, and walked towards his workbench with a small cake in one hand. I am searching……"

"Even if you get the prototype, it's useless," Gu Sheng walked over to him, "'The secrecy of the encryption system should only be based on the secrecy of the key, and should not depend on the secrecy of the encryption algorithm.' This is simply a password The golden rule of learning. I thought about it all afternoon. The biggest advantage of your design lies in the undeterminable key and the secrecy it brings. The correct key can be found out of billions of possibilities."

In cryptography, an encryption algorithm can directly be an abstract mathematical algorithm, such as the general-purpose DEA and RSA algorithms, or it can be an encryption device that implements a certain algorithm or an electronic chip specially used for encryption, because the encryption Secrecy of algorithms is difficult.Adversaries can obtain algorithms, encryption devices or programs by stealing or purchasing them.If you get encryption devices or programs, you can reverse engineer them to finally get encryption algorithms.

If only the key is lost, then only the information related to this key is lost, and the confidentiality of future communications can be remedied by changing the key; but if the encryption algorithm is lost, the confidentiality of the entire system is based on the secret of the algorithm In essence, all information encrypted by this algorithm will be fully exposed.Worse, in order to keep future communications secret, the encryption algorithm must be completely replaced, which means updating the encryption device or changing the program.This would take far greater wealth and management resources than simply changing the keys - changing encryption devices and programs on a large scale would give an adversary a better chance of taking advantage!

"Of course, it's easy to think of... Otherwise, I wouldn't be so troubled to come up with such a thing." Luke dug out the most original notes from a pile of messy waste papers, and threw them to Gu Sheng , "You should broaden your mind. Deciphering codes is really a process full of imagination and passion. You should try to consider the problem from the designer's point of view, and don't stick to some... inherent solutions."

Gu Sheng nodded, and handed him his notes: "These are some loopholes I thought of, take a look."

"..." Luke took it and turned a page, tearing the book angrily, "Didn't you see it all! There are circles in the translation of the rotor! Although these circles are determined by the key of the day, that is, the position of the rotor, they The initial direction and the letter replacement on the connecting plate, but the number of loops in each group and the length of each loop are only determined by the position of the rotor and their initial direction, which are exchanged with the letters on the connecting plate The situation has nothing to do with it!...Fuck, Gu, to be honest, I still can't adapt to your traditional Chinese virtue of 'modestness', you make me look like a self-righteous idiot!"

"Oh." Gu Sheng said, saving his notebook, "...Because these are all based on my brain, and the specific algorithm of the rotor is also compiled by me. After all, there is no ready-made machine for me to try. It is all based on Assuming, it is easy to make a mistake in one step and everything is wrong, I am worried that I am wrong, so I ask you to confirm."

"I don't know...I'm really tired, brother..." Luke broke down, "Did you go to the lecture of that...professor of neuroscience? Do you remember what he said? Every day There is a limit to the amount of time you can keep your attention! The more efficient you invest, the shorter it lasts, brother!... What can we do tomorrow? If I don’t rest, I may not see the sun tomorrow..."

The author has something to say:

All the information in this chapter and the previous chapter comes from Baidu Encyclopedia. The prototype is the German Enigma cipher machine during World War II. The transformation method of the Chinese code is the free imagination of the author. Please feel free... Feel free...