The Historical Process of Deciphering Codes during Chongqing Bombing

8 months: unable to decipher Japanese password

One morning in April, 1938,

The mountain city of Chongqing is foggy.

Wei Daming, the leader of the secret team, looked at a pile of coded telegrams on the table and was at a loss.

Just now, he received a notice from the Technical Research Office of the Military Commission of * * * again, and ordered the password group to decipher the mysterious password as soon as possible.

On the morning of February 18, the secret group intercepted a coded telegram from a Japanese spy lurking in Chongqing.

This telegram presents an unprecedented coding method with mixed Japanese letters.

Before the cryptographer could respond, a dozen similar telegrams appeared in front of them with the interlacing of long and short tones.

The experts who deciphered the secret code group immediately threw themselves into intense work.

Half an hour has passed, and there is still no clue to decipher the secret message.

At this time, the roar of planes from far and near came over the city.

Sharp air raid alarms resounded over Chongqing.

Nine Japanese bombers dropped a dozen bombs, bombing Chongqing for the first time since the Anti-Japanese War.

Intelligence officials were very angry because they didn't get any clues about the attack in advance.

They turned their eyes to the seemingly unbreakable password.

Half a year has passed.

On the morning of October 4th, 65438/KLOC-0, 28 Japanese planes launched a fierce attack on Chongqing, causing more than 60 civilian casualties.

Faced with the aggressive Japanese army and the password that can't be started, the secret group is in trouble.

At this time, Xiao Bo, deputy military attache of the US Embassy, recommended a key figure to Wei Daming.

"The Father of Cryptography": A Clever Digital Interpretation of Meteorological Secret Newspaper

Herbert Yardley is the founder of the US Military Intelligence Agency (the predecessor of today's National Security Agency) and the "American Dark Room" (which is responsible for deciphering coded information obtained by intelligence agencies).

Because of its superior password cracking ability, it is praised as "the father of American passwords" by the industry.

He has studied Japanese code for more than ten years.

165438+ 10, Yardley, alias "Robert Osborne", arrived in Chongqing after many difficulties and dangers at the invitation of the Technical Research Office of the Central Military Commission.

* * * The military awarded him the rank of major, and arranged for more than 30 students studying in Japan to form an intelligence team dedicated to deciphering mysterious codes.

In order to improve the speed of sending telegrams, the Japanese used the letter 10 instead of the number 10 to encode telegrams.

Yardley found through observation that these coded telegrams, which also use only 48 letters in Japanese, also belong to this type.

He converted letters into numbers and made a preliminary decipher of the existing telegram.

According to Yardley's own experience, this is a meteorological coded telegram reflecting the cloud height, visibility, wind direction and wind speed of Chongqing to the Japanese army. The same numbers, such as "027" for Chongqing, "23 1" for 6 a.m. and "248" for noon in each copy.

However, due to the lack of previous meteorological data in Chongqing, it is impossible to infer the specific meaning of each group of numbers from the third group of passwords.

193965438+1October 12~ 15, here comes the opportunity.

Yardley Group intercepts 8 coded telegrams at 6 am, 6 noon and 6 pm every day.

The laws of the numbers in the first group and the second group are the same as those inferred by Yardley before.

The third password of most telegrams is 459, but the sixth password is 40 1.

What do these represent? Inadvertently, his eyes fell on the password interception date under "40 1".

This password was intercepted at noon that day.

At that time, the foggy city of Chongqing suddenly had a clear sky in Wan Li.

In the afternoon, the Japanese sent 27 bombers, killing and injuring more than 200 people.

Yes, "459" means the weather is bad, and "40 1" informs the enemy that they can bomb.

The password is finally unlocked!

Capturing Japanese spies: the situation highlights the tip of the iceberg

Although the password is unlocked, Yardley thinks that if the spy is not caught, the Japanese army will probably use the new password to get our information.

In the next two months, the group intercepted coded telegrams three times and captured the specific source of telegraph signals through the direction finder already prepared.

Soon, the searchers captured Japanese spies disguised as locals in the southern district of Chongqing.

This man was smuggled into Chongqing by a reconnaissance plane not long ago, and was responsible for sending weather code telegrams to the Japanese Air Force Base in Hankou.

Yardley wants the spy to continue sending messages to the Japanese Air Force Base at a fixed time every day to prevent the Japanese side from finding the captured spy and changing the new password.

But unexpectedly, the * * intelligence department secretly shot the Japanese spy soon, so Yardley had to personally send a telegram to the Japanese army to temporarily delay the enemy bombing with false information.

At the same time, the group intercepted a large number of telegrams written in new and more complicated codes.

Yardley judged that there were more hidden spies lurking in Chongqing, and the enemy might launch a new offensive.

But before he reflected the news, at 9 am on May 3, Japanese planes flew directly from Wuhan to Chongqing, dropping more than 100 bombs.

The next day, more than 20 Japanese planes attacked Chongqing again.

The tragic May 3rd and May 4th tragedies in the history of War of Resistance against Japanese Aggression occurred with the blood of 6,000 people in Chongqing.

Adrian is determined to catch the spy as soon as possible.

Just then, a phenomenon caught his attention.

* * * Why didn't the air defense units deployed with great efforts in Chongqing shoot down several enemy planes? There must be a mystery.

Execution of traitors: password secret finally leaked

Yadley pretended to be a fur dealer from the United States and met the battalion commander of an anti-aircraft artillery regiment stationed in Chongqing through acquaintances.

Everyone gave the nickname "one-armed thief".

They are very speculative, but the one-armed thief always smiles noncommittally at the question of why Yardley's sharp anti-aircraft guns can't hit the target.

At the same time, Yardley is facing new challenges.

The new password is a mixture of numbers and English letters.

Through rearrangement, he found that words with practical significance such as "she" and "light" began to appear in the telegram, but where did these words come from and what was their significance? The sentence "He said" in "The Password" caused Yardley to think: the most common place where this sentence caused dialogue was in novels.

Yardley thinks that the source of this new password is probably an English novel. If we can find this novel, we can track it and find the spy hiding behind the scenes.

However, where can I find this novel?

Yardley was greatly encouraged by the news from the Technical Research Office of the Military Commission.

Investigation shows that "one-armed thief" sometimes openly uses the radio station of nearby Sichuan Infantry Division to exchange secret information with one of his "friends" in Shanghai.

He is probably a traitor.

Yardley focused on the one-armed thief.

Yardley took advantage of the one-armed thief's treat to ask a friend with excellent English to write down the words in the telegram in advance and then sneak into the thief's study to see if he could find an English novel containing these words.

After intense searching, she found these words in strokes on the inside page of the famous novel The Good Earth by American woman writer Pearl Buck.

Starting with The Good Earth, Yardley and his team cracked the new code.

According to the password, "one-armed thief" is Wang Jingwei's eyes and ears planted in Chongqing.

He once sent a telegram to the Japanese army, telling its bombers to keep flying at an altitude of 3660 meters to avoid the shooting of the anti-aircraft guns of the * * * army with a range of only 3050 meters.

The secret of the password was finally revealed.

The one-armed thief was quickly arrested and shot.

After this period of time, the Japanese bombing action has been restrained.

1940 July, Yardley returned to the United States.

For the sake of confidentiality, the US did not disclose his news.

Later, Yardley published a detailed story in his memoir "The Darkroom of China-Adventures of the Spy Sea".