How do I generate or find string that can’t be possibly generated by SHA1 encrypting of any input string?
The reason I ask this is because I need a global password placeholder in user table.
Thanks
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How do I generate or find string that can’t be possibly generated by SHA1 encrypting of any input string?
The reason I ask this is because I need a global password placeholder in user table.
Thanks
It depends on the representation you use to store the SHA1-hash, actually. But just a * like sometimes used in /etc/passwd, should work. Actually an empty string would work, too, but I would use something more explicid — like ‘*invalid’
If you are using the standard hex representation (like ’68ac906495480a3404beee4874ed853a037a7a8f’ e.g.), you could use everything that is not a 40digit hex number actually. Use some ascii char, not in [0-9a-f] better yet not in [0-9a-zA-Z].