Back to the Republic of China to be a editor

Indeed, M-209 has six key wheels, which are 26, 25, 23, 21, 19, and 17 bits, and the encryption cycle is as long as 1 million. You can also agree with each army to change the secret key at regular intervals. You can also change the key temporarily.The German army cracked part of the M-209 telegrams during World War II, but it was only a few weeks later that they found the trick to crack it through other clues, which is no longer time-sensitive.

But after technology evolved from the classical age to the computer age, the M-209 became unreliable. In 1970, James Reedus and Robert Morris successfully carried out a ciphertext-only attack on M-209 for the first time, no need to guess, no need to fish to obtain part of the plaintext comparison, as long as the collected ciphertext reaches more than 2000~2500 letters , it can be broken.At that time, the CIA was shocked when they heard the news, and gave them a lot of money to keep the ciphertext-only attack method secret, because although the US military did not use M-209 at this time, some allies and guerrillas in the United States were still using M-209. -209 encryption.Of course, the secret of M-2004 cannot be kept forever. In 209, Heise Online published a technical report on cracking M-1970, listing all the successful methods of M-209 ciphertext-only attacks since [-]. over and over.

"Section Chief Wang, have we obtained the actual M-209?" Tang Hua asked.

"No, maybe the Soviet Union has one." Lao Wang said, "But we know its structure..."

"That's enough." Tang Hua said, "Six rounds of mechanical encryption, the first round is 26, full letters, the second round is 25, lacking w, the third round is 23, missing w, x, y... ..."

Tang Hua crookedly drew six circles on the paper and wrote the numbers.

"Section Chief Wang, we can use a T50 computer as a virtual machine for M-209."

"Oh! That makes sense," Lao Wang said, "I should have thought of it earlier. Anyway, the T50s in your building are not particularly expensive, and I only saw five or six of them. Let me let me come."

Now Pharaoh really wants to operate calculations so that he can practice his hands.Anyway, the M-209 virtual machine is really not difficult to make, so Tang Hua took Pharaoh to a T50 modified machine with original character input and output, and let him play by himself.

Lao Wang first read a few pages of the modified machine's manual, and then began to type.The knocking became slower and slower, and the brain seemed to start to wander.Tang Hua could see that when he was writing the M-209 virtual machine, he was already thinking about how to conduct a ciphertext-only attack on M-209.

"...The exhaustive method requires [-] million conversions of the ciphertext, and also needs to judge whether it is plaintext. The efficiency is too low, so rule it out." Old Wang said to himself.

"The 6-digit secret key of the US military will not be set arbitrarily. It is necessary to ensure that the cycle is at least 1000 million, which can narrow the scope of calculation."

"No, this is still an exhaustive method..."

"Section Chief Wang," Tang Hua said, "Before engaging in M-209's ciphertext-only attack, I think we should make a summary. Encryption should be divided into two elements. The first element is the algorithm, and the second element is the secret code." key. Now we have obtained the algorithm of M-209, and turn to ask for his secret key."

Lao Wang glanced at Tang Hua and nodded again.

While Lao Wang and Tang Hua were talking, Lao Wang kept on working and quietly made the M-209 virtual machine.This T-50 modification machine is modified to verify the components on the TC50 supercomputer. It not only has the original character input and output functions, but also has a 16-segment segment code screen, which is still 3 lines.Lao Wang ran the program, and then typed in a line of dozens of letters. After starting the calculation, ciphertext appeared on the screen—dozens of letters that seemed to be irregular.

Holding two pieces of paper in plaintext and ciphertext, Lao Wang pasted them on the schematic diagram of M-209, and fell into deep thought.

……

Jilin, Tonghua, Wunvfeng.

Li Qiang led a small team from the Communications Bureau to climb to the top of Tiannv Peak.

"How far is it from the border between China and North Korea?" Li Qiang asked.

"About fifteen kilometers!"

"Could it be any closer?" Li Qiang looked towards the southeast, which is the border between China and North Korea. There were mountains and deep ravines layered on top of each other, with no end in sight. "Although Tiannv Peak is a commanding height, the peaks here are too dense, affecting the accuracy of radio positioning! What is the name of the mountain in front? Is it in our country?"

After the founding of New China, Li Qiang, who was well-known in the party for his versatility, was named by the prime minister to do foreign trade. From October 49 to June 10, he went to the Soviet Union twice for business negotiations.Originally, he was appointed as the deputy minister of the Ministry of Foreign Trade and the commercial counselor of the embassy in the Soviet Union. work to go.

Specifically, he is now the deputy director of the Communications Department of the Military Commission, partnering with Wang Zheng, but his main work in the near future is mountain climbing—set up several radio listening stations on the Sino-North Korean border as close to the North Korean land as possible to detect Listen to and collect wireless telegrams within North Korea, record them, and quickly send them back to the "50 Center" whose name is very mysterious.

The U.S. military currently uses the M-209 cipher machine mainly for division-regiment-battalion-level troops. These troops are equipped with low- and medium-power short-wave radio stations with a transmission distance of several hundred kilometers. Therefore, the closer to the battlefield, the better the effect of radio interception stations.After understanding the intention of the Military Commission, Li Qiang first determined the approximate locations of the six listening stations, and then began to lay temporary telegraph lines and time synchronization lines, so that he could use triangulation to calculate the location from which the intercepted telegrams were sent.Next, the information from the six listening stations was summarized. According to the Military Commission's standard, the wired and telegraph lines were pulled all the way to... Fengman Hydropower Station?

"Minister Li, that mountain is called Longshan. It looks very high, but it's actually not that high. Look at the map. If it's located on Longshan, there are actually two directions blocked by higher mountains in North Korea!"

Li Qiang took the map and checked it carefully against the contour line. It is true that the location of Longshan is not as good as that of Tiannvfeng. "Then set Listening Station No. 5 here! Note down the location here, and let the engineering team of the Communications Bureau start working now."

The engineering team of the Communications Bureau has already pulled the equipment on the road below the mountain and waited for Li Qiang to confirm the location before starting construction. First, a temporary wired telegraph network was laid, and then the listening equipment was brought to the top of the mountain.

After Li Qiang surveyed the No. 5 site, he walked down the mountain step by step carefully.He also guessed that this series of orders from the Military Commission was to intercept the enemy's telegrams in North Korea, and the 50 Center should be the technical agency to crack the U.S. military's telegrams.There is no problem in intercepting the telegram, but can it be cracked?Li Qiang knows that the encryption system used by the US military was not really cracked during World War II. Instead, the German Enigma machine, which claims to be very technologically advanced, was cracked. How the Enigma machine was cracked.

If our army can crack the U.S. military's cipher machine, does that prove that China's intelligence capabilities even overwhelm the U.S., thereby countering the preemptive opportunity on the battlefield?

Chapter 61, Incheon Drama

"The third revision of the operating system has been entered, what is the version sequence called? 1.3?"

Lebedev fed the second long paper tape into the input port, the computer read the data, and then displayed a line of letters on the segment code screen, indicating that the data had been written into the magnetic core memory.

"Operation 1.03, that is ос1.03." Tang Hua said.

Lebedev walked to the switch, closed the switch, and pressed a button on the console, and a deep roar sounded in the supercomputer hall.The green indicator lights of the 12 cabinets arranged in an X shape are all lit up, indicating that the TC50 supercomputers are all ready.

If it is said that the computing power of a T50 computer is equivalent to the sum of the computing power of all the computer systems in the entire Soviet Union, then the computing power of a TC50 computer has already exceeded the sum of the computing power of all the computers produced by other countries on the earth (of course, it must be excluded Dozens of TC50s have been produced and sold in China). Among the 12 cabinets, 8 are computing cabinets, and each cabinet is equipped with 20 computing units.There are 4 comprehensive operation cabinets, all with input and output and memory, which can be operated and used by 4 staff at the same time if necessary. Behind the operator seats of the 4 integrated operation cabinets is the main console.The supercomputing hall is now divided into four triangular areas by the X-shaped layout of TC50, one control area and three maintenance areas.

Although the supercomputer hall has a high-power ventilation and cooling system, after more than ten minutes of operation, everyone still felt that the temperature in the control area was rising.Lebedev, who was meticulously dressed, also loosened his tie at this time, and unbuttoned the first button of his shirt to dissipate heat.

"The third version of the system should be the most stable," Lebedev said. "If you use it normally, you don't need to restart it for a few days."

"The operating system should be like this," Tang Hua smiled, and looked at his watch again. "It's past five o'clock, and the system is normal so far. The rest of the test can be handed over to the operator. Why don't we decide?" Now, where are you going to have dinner? Is it the Volga, or the Renaissance? The Tkachenko brothers?"

"I suggest the Tkachenko brothers." Lebedev replied immediately.

Wang Yongjun watched the two quickly set the place for dinner, hesitated for a long time and did not respond, his face was troubled.The first cracking test will be conducted tonight...

"Old Wang, don't be afraid, that Russian restaurant was not ten or twenty years ago, and the remnants of White Russia have long since disappeared. If you are still worried about the risk of exposure, here you are," Tang Hua conjured up a pair of big sunglasses and a sun hat with a big brim , put it on Old Wang's head, "We have to continue talking about cracking the program while eating."

In the quiet corner of the Tkachenko Brothers Cafe, the three chatted endlessly while eating.

"Old Lie, have your wife and children already left for China?" Tang Hua asked.

"They're on the Trans-Siberian Railway," Lebedev said. "They left Moscow last week, and they're about four weeks away."

Tang Hua picked up the borscht in front of him with a spoon. The bright red thick soup was quite solid, and he could scoop out a pile of beef cubes at the bottom.The tonkatsu is also large and thick, anyway, all the dishes are very generous. "Old Wang, you must have enough to eat tonight, maybe you will have to do it all night."

"I'm wondering if there's any possibility to optimize the program," Lao Wang was a little absent-minded just now, and when he heard Tang Hua's words, he picked up the bread and dipped it in the soup and gnawed, "According to the computing power of TC50, it is expected that the ciphertext-only attack will reach 12 hours, if..."

Supercomputer Hall.

Lebedev returned home from get off work after dinner, and Lao Wang and Tang Hua returned to the computer office.The Intelligence Department of the Military Commission will conduct the first ciphertext attack test against M-209 this evening.

Tang Hua took the code draft and looked at it for half an hour. Lao Wang's new solution was more targeted. The six-wheel structure of M-209 and the displacement of drum lugs can actually be described by mathematical models. , Just leave the mathematical calculations to the computer.Now Tang Hua wants to develop a dedicated decryption chip, ah, not to decrypt the computing unit. When he designed the TC50, he slightly focused on the integral calculation on the hardware, because the main user group uses it for scientific research and engineering calculations. A common calculation is to find the exact numerical solutions of various differential equations & definite integrals.

After re-optimizing a small process of the code, Tang Hua felt that it was ok.

The T209 modified machine, which was regarded as the M-50 virtual machine, started to run. Tang Hua entered six letters to set the initial state of M-209, then took an English newspaper and began to enter plain text. The T50 modified machine output the ciphertext almost immediately.After entering half a page of the newspaper content, and seeing that there were already 2500 letters, Tang Hua stopped the encryption process and handed the ciphertext to Lao Wang.Lao Wang took the ciphertext, walked to the TC50 main console where the decryption program had been started, coughed lightly, and let the four cracking operators in front of the comprehensive operation cabinet enter the state.

At 10:10 p.m., Shanghai was brightly lit at night, and Tang Hua half-lyed on a chair on the balcony of the computer office, looking at the night sky to pass the time.

The TC50 in the building is running at full power. This big guy consumes 90 kilowatts of power, and the cooling system consumes another 4 kilowatts of electricity. The computer institute has specially modified the power supply line for this purpose.

"Minister Tang, are all password systems vulnerable to computers in the future?" Old Wang realized that he was waiting for nothing, so he also came to the terrace to watch the night view.

"This is the collision between the classical encryption system and the computer age, just like the transformation of cold weapons and hot weapons," Tang Hua said. "The classical encryption system will eventually be eliminated and replaced by computers."

"Well, I think so. The classical encryption system is no match for a computer. Only by using a computer to encrypt can it be possible to defeat the computer's decryption program. The confrontation between the spear and the shield will never stop." Old Wang nodded.

……

"Section Chief Wang, Section Chief Wang" the cracking operator came to the terrace and gently called Old Wang.