JWT - JsonWebToken rucne

https://medium.com/@bn121rajesh/rsa-sign-and-verify-using-openssl-behind-the-scene-bf3cac0aade2 https://stackoverflow.com/questions/59002949/how-to-create-a-json-web-token-jwt-using-openssl-shell-commands https://techdocs.akamai.com/iot-token-access-control/docs/generate-jwt-rsa-keys #!/bin/bash #file which contains your JWT file="payload.txt" echo "########### "Insert google signed JWT now: read content echo echo $content > $file echo echo #decalre function which fixes b64 decode_base64_url() { local len=$((${#1} % 4)) local result="$1" if [ $len -eq 2 ]; then result="$1"'==' elif [ $len -eq 3 ]; then result="$1"'=' fi echo "$result" | tr '_-' '/+' | openssl enc -d -base64 } #extract parts from payload cat $file | cut -d'.' -f1 >payload1.raw cat $file | cut -d'.' -f2 >payload2.raw cat $file | cut -d'.' -f3 >payload3.raw #prepare and show data which are signed echo "########### Signed data:" decode_base64_url $( cat payload1.raw ) echo -n "." decode_base64_url $( cat payload2.raw ) echo -n $(cat payload1.raw)"."$(cat payload2.raw) > payload12.raw #prepare signature decode_base64_url $( cat $file | cut -d'.' -f3 ) >payload3.txt echo echo #go through all keys and find which one is working for F in $( ls "/tmp/google_ca_history/" | grep -v google ) do echo "#########" echo CHecking signature with file: /tmp/refresh_cert/"$F" openssl dgst -sha256 -verify "/tmp/google_ca_history/"$F -signature payload3.txt payload12.raw echo done