How To Check Integrity Of Files In Linux?
In today IT world everything connected and a lot of data in being downloaded from internet or over networks. This may create some minor problems. The data downloaded may be corrupted or there may be some intruders in network and with man of the middle attack may change our files. There are different solutions for this but simplest and fastest solution is using hash algorithms to verify file integrity. There are different hash function to use but MD5 and SHA1 is popular ones
We will download
nmap package named
nmap.org . We will use this file as a example where this file hash is all ready provided by nmap web site.
$ wget https://nmap.org/dist/nmap-7.21.tgz
Get Hash Values From Site
We will calculate hash of downloaded file nmap-7.31.tgz
Here is the contents of the hash file
We will use
sha1sum to calculate
md5sum to calculate
sha24sum to calculate
sha512sum to calcualte
SHA512 of the given file.
$ sha1sum nmap-7.31.tgz
$ md5sum nmap-7.31.tgz
$ sha224sum nmap-7.31.tgz
$ sha512sum nmap-7.31.tgz
As we see newer SHA version creates longer hash because they are more secure and complex. If we check calculated hash and web site provided hash we can see that everything is OK.