Generating RSA Private and Public Key Pair in Go Lang?

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How to generate a pair of RSA private and public key in Go lang? Go lang has a rich set of standard libraries. Using Go’s standard libraries, we can generate RSA private and Public keys. The Crypto standard libraries in Go lang Go lang standard libraries has a rich set of cryptography functions. Here are
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How to Install Wine 32-bit on CentOS 8

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Since version 7, RHEL and CentOS only have 64 bit versions. For some reasons, it’s better to run many Windows applications under 32 bit wine. Like How to Install Wine 32-bit on CentOS 7, this post introduce how to install 32-bit Wine on CentOS 8. Most of the mechanisms are similar yet there are differences.
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Hiding Private IP from Email Headers in Thunderbird

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It seems Thunderbird sends out my private/lan IP to the SMTP server. For example, in an Email sent out by Thunderbird, the header contains Received: from [192.168.1.2] (example.com [1.2.3.4]) by mail.example.com (Postfix) with ESMTPSA id 92CD297DEA; It is fine that the SMTP server records the public IP (1.2.3.4) as it is what it sees. But
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How to choose the key used by SSH for a specific host?

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How to choose a key used rather than the default ~/.ssh/id_rsa when ssh to a remote server for a specific host? You have at least 2 choices for choosing the key used by ssh. Taking ~/.ssh/key1 and user@example.com as the example here. Method one, specify the key in command line with the -i option of
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How to Passwordless SSH to an OpenWrt Router?

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The good ssh-copy-id method which works well on common Linux seems not working for OpenWrt router. How to Passwordless SSH to an OpenWrt Router? OpenWrt’s SSH server is Dropbear. It can accept normal RSA keys. But the authorized_keys location is not the same as the openssh “~/.ssh/authorized_keys”. The location for the authorized_keys is /etc/dropbear/authorized_keys What
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VirtualBox report “Kernel driver not installed” on Fedora 21

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VitualBox is installed on Fedora 21 by # yum install VirtualBox The following packages are installed kmod-VirtualBox-3.18.7-200.fc21.x86_64-4.3.20-4.fc21.4.x86_64 VirtualBox-4.3.20-3.fc21.x86_64 There is the kernel modules package installed. However, when running virtualbox (after reboot), it reports: [zma@laptop:~]$ virtualbox WARNING: The vboxdrv kernel module is not loaded. Either there is no module available for the current kernel (3.18.7-200.fc21.x86_64) or
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Decrypting a Password Protected RSA Private Key

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I got a password protected RSA private key with headers like (I have the password): —–BEGIN RSA PRIVATE KEY—– Proc-Type: 4,ENCRYPTED DEK-Info: AES-256-CBC,… How to decrypt a password protected RSA private key? You can use the openssl command to decrypt the key: openssl rsa -in /path/to/encrypted/key -out /paht/to/decrypted/key For example, if you have a encrypted
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ssh error with message “WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!”

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I got an error message when ssh to a server like: @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ @ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY! Someone could be eavesdropping on you right now (man-in-the-middle attack)! It is also possible that a host key has just been changed. The fingerprint for
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Howto for New Git Users

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This post is a tutorial for new users to set up git and clone and use the first repository. This post introduces how to start using git for new users. This post does not introduce details of how to use git commands. Please refer to the git manual or other tutorials for how to commit,
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How to Set Up Password-less SSH Login on Linux

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Automatic passwrod-less ssh login can make our life easier. To enable this, we have 2 options: using key-based authentication by copying our SSH public keys to the remote machines for automatic password-less login or using password-based authentication. I will introduce the 2 options in the post. Before you start, please note that key-based authentication is
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Setting Up a Git Server Using Gitosis

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Update: Since gitosis is not maintained and supported, please check out gitolite for setting up a new git server. (see the comment from Sitaram Chamarty, the gitolite author, the author of gitolite.) Gitosis is a piece of software writen by Tommi Virtanen for hosting git repositories. It manages multiple repositories under the same user account.
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