As of now, the MD5 encryption algorithm is irreversible.
The reason why MD5 is irreversible is that it is a hash function (also called hash function, hash function). It is a one-way cryptosystem, that is, an irreversible mapping from plaintext to ciphertext. Only the encryption process There is no decryption process).
The hash function can change an input of any length to obtain a fixed-length output. This fixed-length output is called the hash or message map of the original message. An ideal hash function can get different outputs for different inputs. If two different messages get the same hash value, we call it a collision.
The hash algorithm is used, and part of the information in the original text is lost during the calculation process.
One MD5 can theoretically correspond to multiple original texts, because there are finitely many MD5s and infinitely many original texts.
MD5 code is a 128-bit binary number. There are up to 2^128 possibilities, but the number of strings obviously has countless possibilities.
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