Gurjeet Singh gurjeet

Native Secure Enclave backed ssh keys on MacOS

It turns out that MacOS Tahoe can generate and use secure-enclave backed SSH keys! This replaces projects like https://github.com/maxgoedjen/secretive

There is a shared library /usr/lib/ssh-keychain.dylib that traditionally has been used to add smartcard support to ssh by implementing PKCS11Provider interface. However since recently it also implements SecurityKeyProivder which supports loading keys directly from the secure enclave! SecurityKeyProvider is what is normally used to talk to FIDO2 devices (e.g. libfido2 can be used to talk to your Yubikey). However you can now use it to talk to your Secure Enclave instead!

PostgreSQL is Enough

Background and Cron Jobs

Install and use pip in a local directory without root/sudo access.

By: @saurabhshri

Why?

Many users when are given server access, do not have root (or sudo) privileges and can not simply do sudo apt-get install python-pip . Here's an easy way you can install and use pip without root (or sudo) access in a local directory. Note : This works without easy_install too.

How?

Setting up Crashplan on FreeNAS Goals

Be able to backup from the FreeNAS box to offsite Crashplan Central. Allow incoming Crashplan backups from other devices. Install the CrashPlan plugin

Install the plugin into a jail: Click on Plugins, then the Available tab, the "crashplan" line and finally the Install button. Once the installation completes, on the left tree, expand Plugins and click on CrashPlan. Accept the Java EULA. Start the Crashplan plugin: Plugins->Installed and make sure the Crashplan plugin is in the "ON" position.

Each of these commands will run an ad hoc http static server in your current (or specified) directory, available at http://localhost:8000. Use this power wisely.

Discussion on reddit.

Python 2.x

$ python -m SimpleHTTPServer 8000

	/* this is the box (and the version) that we want to download from: https://app.vagrantup.com/debian/boxes/jessie64 */
	wget https://app.vagrantup.com/debian/boxes/jessie64/versions/8.9.0/providers/virtualbox.box -O debian-jessie64-8.9.0.box

	/* add the box to vagrant */
	vagrant box add debian/jessie64 debian-jessie64-8.9.0.box

	/* update box version */
	cd ~/.vagrant.d/boxes/debian-VAGRANTSLASH-jessie64/
	mv 0 8.9.0

	/**
	* Fancy ID generator that creates 20-character string identifiers with the following properties:
	*
	* 1. They're based on timestamp so that they sort after any existing ids.
	* 2. They contain 72-bits of random data after the timestamp so that IDs won't collide with other clients' IDs.
	* 3. They sort lexicographically (so the timestamp is converted to characters that will sort properly).
	* 4. They're monotonically increasing. Even if you generate more than one in the same timestamp, the
	* latter ones will sort after the former ones. We do this by using the previous random bits
	* but "incrementing" them by 1 (only in the case of a timestamp collision).
	*/

	/**
	* A proxy for loading static files in development. Django doesn't handle this well.
	*
	* To run, do something like:
	* npm install .
	* node proxy.js --docroot=$PWD
	*
	* Then just visit http://localhost:9000/ as you normally would.
	*/
	var httpProxy = require('http-proxy');

	// This is from my comment here: http://wolfram.kriesing.de/blog/index.php/2008/javascript-remove-element-from-array/comment-page-2#comment-466561

	/*
	* How to delete items from an Array in JavaScript, an exhaustive guide
	*/

	// DON'T use the delete operator, it leaves a hole in the array:
	var arr = [4, 5, 6];
	delete arr[1]; // arr now: [4, undefined, 6]

	# use ImageMagick convert
	# the order is important. the density argument applies to input.pdf and resize and rotate to output.pdf
	convert -density 90 input.pdf -rotate 0.5 -attenuate 0.2 +noise Multiplicative -colorspace Gray output.pdf