cipher

Classical cryptography algorithm has been widely used, mostly simpler, using manual and mechanical operation to achieve encryption and decryption. Its main application object is the text information, uses the cipher algorithm to realize the text information encryption and the decryption. Two common classical cryptographic algorithms are described below to help readers create a preliminary impression of a cryptographic algorithm. 1. Alternate password

; theasc_space[i]123)//A- Z conversionasc_space[i]-= the; } returnAsc_space;}voidEncode (CString key,cstring plain,cstring cipher) { //Virginia Encryption Algorithm int*keycode=Cstringtoint (key); int*plaincode=Cstringtoint (plain); int*ciphercode=Cstringtoint (plain); intKeysize=key. GetLength (); intPlainsize=Plain. GetLength (); intflag=0; CString Blank (' ', plainsize+1);//Reserve a byte to put inCipher=blank;//Create a blank

Original question: Ancient Roman Empire had a strong government system with various departments, including a Secret Service department. Important documents were sent between provinces and the capital in encrypted form to prevent eavesdropping. The most popular ciphers in those times were so called substitution cipher and permutation cipher. Substitution cipher Ch

At the end of the semester, tutorial information security Introduction operations. The Playfair algorithm in the Classical cryptography algorithm and hill algorithm, in JavaScript language to realize it is interesting, while looking for Baidu side code, by the way a good tutorial JavaScript base.PlayfairPlayfair Password (English: Playfair cipher or Playfair Square) is a replacement password. written according to a

In CFB mode, the previous ciphertext packet is sent back to the input of the cryptographic algorithm. The so-called feedback, which refers to the meaning of the return input, as shown:In the ECB mode and CBC mode, the plaintext packet is encrypted by the cipher algorithm, whereas in the CFB mode, the plaintext packet is not encrypted directly by the cipher algorithm.We can see the difference between the CBC

1712. Cipher GrilleTime limit:0.5 SecondMemory limit:64 MBOur program committee uses different tools for problem development:a mailing list, a version control system, an ADMINISTR ation System of theTimus Online Judge website, and many others. Chairman of the program Committee must constantly keep the passwords for these systems in his head. Of course, the passwords must is kept secret from the contestants, otherwise the problems could become known to

This article mainly introduced the Python implementation of the Caesar cipher algorithm, briefly introduced the Caesar cipher concept, the principle and combined with the example form analysis Python to realize the Caesar cipher algorithm related definition and the use Operation skill, needs the friend can refer to the next In this paper, we describe the Caesar

At the end of the semester, tutorial information security Introduction homework. Just encounter the classical cryptography algorithm Playfair algorithm and hill algorithm, using JavaScript language to achieve is in the fun, while Baidu Edge code, by the way a good tutorial on JavaScript basics. Playfair Playfair Password (English: Playfair cipher or Playfair Square) is a replacement password. Based on a 5*5-square

SSL handshake failure resolution between IOS and Java server: Cipher SuitesThe beautiful Life of the Sun Vulcan (http://blog.csdn.net/opengl_es)This article follows "Attribution-non-commercial use-consistent" authoring public agreementReprint Please keep this sentence: Sun Vulcan's Beautiful Life-this blog focuses on Agile development and mobile and IoT device research: IOS, Android, HTML5, Arduino, Pcduino , Otherwise, the article from this blog re

CTR Mode is a stream cipher that generates a key stream by encrypting successive accumulated counters, and in CTR mode, each packet corresponds to a successive cumulative counter, and the key stream is generated by encrypting the counter. The final cipher packet is obtained by XOR the bit sequence encrypted by the counter and the plaintext packet, as shown in:The method for generating the counter is as foll

account folder, there is such a big "power" it? Open the file with Notepad and see what you see (Figure 2)! In fact, almost all of the content you set up in Foxmail's account → Properties menu is included (if you're careful, you'll find "templates" in "Properties" are not included), including encrypted mailbox cipher ciphertext, which is "pop3password=." The back part. Now let's talk about this interesting topic. Foxmail Analysis Let's assume th

Here is a cipher encrypted by the classic cipher algorithm (the encryption algorithm is unknown):YvvnerujjvnywhbdvkpchfgvjtzwqsuporqfzpoekkjgziicdwwkeejdsruefWhwseyejejhnaeepjbjwnuztavjswrthswlcdxqrnoclsodkrrfjtfhlfznbxWyvdwdcwyzqlqrnevuiiienxzmwtdsyhgstwmvznrvhyihhcxjijhiojphvjwSrpejwnhrhirqbcdwnzqmwjpoibnbjdeshloewcfdhvzjgtdwsvntydyweyllGjrrohfuyplppzrssvniejxhzjtrwyvvdecpttrieevhzlxsvunstovzwjfsaSvlsgzjc

Substitution, S-box, diffusion and confusion, these concepts form the basis of group cryptography.if the packet length of plaintext and cipher is n-bit, then each packet of clear text has 2n possible value ;Substitution:In order for the cryptographic operation to be reversible (that is, the decryption operation is feasible), each packet of clear text should produce a unique ciphertext grouping (many-to-one), soThe transformation is reversible, and the

Please help me with this simple problem. i'm trying to create an sslserversocket that is enabled with the 2 AES 256-bit cipher suites that are supposed to be available in jdk1.4.2. as you can see in the following code, when the program attempts to enable the sslserversocket, SS, with cipher_suites, an exception occurs. the exception basically says that the tls_dhe_rsa_with_aes_256_cbc_sha cipher Su ITE wasn

Two times Unicom gate: Bzoj 1031: [JSOI2007] character encryption cipher/*bzoj 1031: [JSOI2007] character encryption cipher Copy the original string once and then ask for the suffix array again*/#include#include#defineMax 1000008voidRead (intNow ) {RegisterCharWord =GetChar (); for(now =0; Word '0'|| Word >'9'; Word =GetChar ()); for(; Word >='0' Word '9'; now = now *Ten+ Word-'0');} InlinevoidSwap (int*a

In ECB mode, the results of plaintext packet encryption are grouped directly as ciphertext, as shown in:When using ECB mode encryption, the same plaintext groupings are converted to the same cipher groupings, that is, we can interpret them as a large "plaintext grouping → ciphertext grouping" table, so the ECB mode is also known as the electronic cipher mode.ECB mode benefits:1. Simple2. Facilitates paralle

research: a major theoretical problem that has not been solved in a discipline for a long time, and if it breaks through the limitations of the subject, it may be possible to make a major breakthrough by using multi-disciplinary joint inquiry method.Take the quantum cipher as an example, since the birth of human civilization, there is a need for secrecy. For thousands of of years, secrecy and spy, like Spears and shields, are shadow, and the struggle