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View Full Version : So I thought I understood MD5, but...



KC2UGV
04-30-2013, 07:21 AM
... it appears I don't. Was verifying integrity on a system binary for a machine. I compared the md5sum of that binary to several other machines I have, running the same version/arch/etc.

Some of the md5sums were the same, but a lot of them were different from each other even. rpm -V checks out, as does yum-verify. Is there something else at play here (Such as atime, ctime, mtime, etc?)

W4GPL
04-30-2013, 10:31 AM
prelink will change the binary's md5sum.. yet properly verify via RPM.

KC2UGV
04-30-2013, 10:52 AM
Well, that makes a whole lot more sense now, and rpm -V is pre-link aware... Thanks!

W4GPL
04-30-2013, 10:58 AM
This was a big problem with Tripwire when they first implemented prelinking. I think Tripwire has since added a plugin to deal with it though.