Shell script to validate file sha256 hashes. I use this to check if downloaded binaries are correct in Dockerfiles. This might make updating harder but at least it you see which parts have been updated since the last run.

validate_sha256sum

#!/bin/sh
##
# This script contains helper for sha256 validating your downloads
#
# Source: https://gist.github.com/onnimonni/b49779ebc96216771a6be3de46449fa1
# Author: Onni Hakala
# License: MIT
##

# Stop program and give error message
# $1 - error message (string)
error () {
   echo "ERROR: $1"
   exit 1
}

# return sha256sum for file
# $1 - filename (string)
get_sha256sum() {
    cat $1 | sha256sum | head -c 64
}

# Good variable names pls
filename=$1
file_hash=$2

# Check input
if [ -z "$filename" ]; then
    error "You need to provide filename in first parameter"
fi

if [ -z "$file_hash" ]; then
    error "You need to provide sha256sum in second parameter"
fi

# Check if the file is valid
if [ ! -f $filename ];
then
    error "File $filename doesn't exist"
elif [ "$(get_sha256sum $filename)" = "$file_hash" ]; then
    echo "Success: $filename matches provided sha256sum"
else
    error "$filename doesn't match provided sha256sum"
fi