how to use a key in md5 algorithm in c#
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hi please tell me how to use a key in md5 encryption algorithm and how can I decript using MD5
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hi please tell me how to use a key in md5 encryption algorithm and how can I decript using MD5
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Down vote countered.
Those who fail to learn history are doomed to repeat it. --- George Santayana (December 16, 1863 – September 26, 1952) Those who fail to clear history are doomed to explain it. --- OriginalGriff (February 24, 1959 – ∞)
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hi please tell me how to use a key in md5 encryption algorithm and how can I decript using MD5
It doesn't matter how often you down vote people, that won't change the facts: MD5 is not an encryption algorithm, and the output cannot be decrypted back to regenerate exactly what was input. This is because it is a Hashing algorithm, which "throws away" information when it generate the MD5. It effectively works klice the more primitive SUM for generating a checksum:
byte sum = 0;
foreach (byte b in myData)
{
sum += b;
}Although this generates a "unique" code which can verify that the myData is unchanged (to a limited extent) you cannot take the single byte output and regenerate the exact input from just that. MD5 (and SHA) work the same way: they use and discard information to get a value that can give you a very high confidence that the data is unchanged, but it can't be "decrypted" back to the original input. Otherwise, we would just store the MD5 of a video file and transfer just 128 bits instead of 700Mb and just "decrypt" it at the destination...
Those who fail to learn history are doomed to repeat it. --- George Santayana (December 16, 1863 – September 26, 1952) Those who fail to clear history are doomed to explain it. --- OriginalGriff (February 24, 1959 – ∞)
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It doesn't matter how often you down vote people, that won't change the facts: MD5 is not an encryption algorithm, and the output cannot be decrypted back to regenerate exactly what was input. This is because it is a Hashing algorithm, which "throws away" information when it generate the MD5. It effectively works klice the more primitive SUM for generating a checksum:
byte sum = 0;
foreach (byte b in myData)
{
sum += b;
}Although this generates a "unique" code which can verify that the myData is unchanged (to a limited extent) you cannot take the single byte output and regenerate the exact input from just that. MD5 (and SHA) work the same way: they use and discard information to get a value that can give you a very high confidence that the data is unchanged, but it can't be "decrypted" back to the original input. Otherwise, we would just store the MD5 of a video file and transfer just 128 bits instead of 700Mb and just "decrypt" it at the destination...
Those who fail to learn history are doomed to repeat it. --- George Santayana (December 16, 1863 – September 26, 1952) Those who fail to clear history are doomed to explain it. --- OriginalGriff (February 24, 1959 – ∞)
What you are stating is not true - You can revert MD5 if you don't exceed the maximum of 1 byte :laugh: :laugh:
The scariest moment is always just before the Start - Stephen King
Die Frauen warten auf die Liebe, und die Männer warten auf die Frauen - Wolf Wondratschek -
hi please tell me how to use a key in md5 encryption algorithm and how can I decript using MD5
While it seems unlikely that you actually meant to ask "how can I generate a pre-image of an MD5 hash", that would be a much more interesting question, so I'll pretend you asked it. In general, that's still "very hard". That is, given a random MD5 hash x, it's not (yet) feasible to compute a string that would hash to x (though there is an 2123.4 attack, which is better than brute force). By the way, there is obviously an unlimited number of strings that would have the same hash, because there's an infinite number of different strings and only a finite number of MD5 hashes. So in general it's not possible to get the actual original string, but you may find a string that has the same hash, and for short strings there's a very good probability that you would have found the original. By contrast, generating two strings that have the same MD5 hash is efficiently doable[^] and highly realistic. If you know something about the key, for example that it's an 8-letter alpha-numeric string, a brute force attack is often very feasible - for this example, it would take several hours on a good GPU. (26+26+10)8 / 10GH/s[^] = about 6 hours, and you could buy a better GPU, or several. MD5-ed passwords hashes can also be easy, it depends. On the one hand, it's obviously possible to make a long random password, and you won't crack it. But on the other hand, most passwords used in real life are not like that. See for example this article[^] about some of the subtleties of passwords.
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What you are stating is not true - You can revert MD5 if you don't exceed the maximum of 1 byte :laugh: :laugh:
The scariest moment is always just before the Start - Stephen King
Die Frauen warten auf die Liebe, und die Männer warten auf die Frauen - Wolf WondratschekHmm. Yes, that would work. I must immediately encrypt each byte of my files into MD5... ...hang on, why did they all get 32 times larger? :laugh:
Those who fail to learn history are doomed to repeat it. --- George Santayana (December 16, 1863 – September 26, 1952) Those who fail to clear history are doomed to explain it. --- OriginalGriff (February 24, 1959 – ∞)
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hi please tell me how to use a key in md5 encryption algorithm and how can I decript using MD5
