SSL - Generate RSA Key

To simply generate rsa key to stdout in default 512

OpenSSL> genrsa

For 1024

OpenSSL> genrsa 1024

For saving it to file

OpenSSL> genrsa -out mykey.pem 1024

To generate public RSA key, use
OpenSSL> rsa -in mykey.pem -pubout

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SSL - Generate RSA Key

OpenSSL Introduction

To encrypt a text file use:

OpenSSL> enc -base64 -in myfile.txt

or
OpenSSL> enc -base64 -in myfile.txt -out myfile.txt.enc
or just a test using pipe
D:\git\bin>echo "Hello World" | openssl enc -base64
To decrypt, use
OpenSSL> enc -base64 -d -in myfile.txt.enc
To decrypt from pipe, use
D:\git\bin>echo "encrypted" | openssl enc -base64 -d
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OpenSSL Introduction