Android OS Forum banner
1 - 1 of 1 Posts

· Android Apprentice
43 Posts
DeTard said:
The point has been missed. My point wasn't that devs are sloppy and make clumsy mistakes all the time. My point was that if you ever do see an MD5 that is incredibly close to what you were expecting to see, it's more likely a typo than a corrupt download and that you should inquire with the dev and/or others that have downloaded the file. My reasoning for talking about modifying a single character in a large file that was >400MB was to demonstrate that even with something as minuscule as one character off, the whole MD5 will be altered and that if you have a very very close MD5 but not identical, it was a human error, not a bad download. Yes, I agree, you can brick your phone with a bad download. But I also am trying to point out that sometimes it's best to inquire with others than to assume you were the only one receiving a "bad" MD5 hash.

Also, this wasn't an effort to say someone else was wrong. This was to add to understanding that MD5s are calculated on the whole file (or to be more accurate, the whole data). I didn't mean this to turn into a pissing contest. I fully accept that my peen is the smallest. :)
No need to provide further explanation, your first post was 100% correct. With so many possible combinations, it is so statistically unlikely to have an md5 off by one digit that you can confidently throw that possibility out.

Using the same concept, there is no 100% guarantee that the file is the same even if the md5 matches! The corrupt file could technically still calculate the same md5 as the original file. The original designers of the md5 hash knew this so they purposely made the hash contain many digits. When I verify a hash I only look at the last 4-5 digits for this very reason.

Sent from my ADR6400L using Tapatalk
1 - 1 of 1 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.