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blog/2019-03-11_introduction-to-qemu.md

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+# Introduction to QEMU for Hackers
+
+One of the things that I've noticed in the infosec community is the tendency to
+stick to the proprietary virtualization tools that are familiar.
+People often are quick discount tools that they don't already know, so I have
+written this blog post in an attempt to foster an interest in exploring other
+virtualization options.  My hope is that, even if you don't come away wanting to
+use QEMU in your CTF lab or malware analysis playpen, you will at least be more
+open to looking into other forms of emulation and virtualization.
+
+## The Case for QEMU
+Many hacking event organizers spend ample time pointing and clicking through
+their VirtualBox and VMware configuration wizards to setup their hacking labs.
+What if I told you there was a better way that works on Linux, macOS, Windows,
+and Xen?
+
+### Enter QEMU
+With [QEMU](https://www.qemu.org/) your VMs are defined as the arguments passed
+to QEMU on its invocation at the command line.  For example, you might invoke a
+VM as such (note that **`>`** is a
+[**$PS2** prompt](http://tldp.org/HOWTO/Bash-Prompt-HOWTO/x157.html)):
+```
+$ qemu-system-x86_64 -machine type=q35 --enable-kvm -cpu host -smp cpus=8 \
+> -m 512M -netdev user,id=net0 -device e1000,netdev=net0 -hda dsk/vm-hdd.qcow
+```
+
+### Shell Scripts as VM Templates
+
+Obviously this isn't a good long-term way to run your VM, but fear not, as there
+is a better way!  All you have to do is save your VM arguments to an executable
+shell script like the following:
+```
+#!/usr/bin/env bash
+
+# image creation command:
+# qemu-img create -f qcow2 -o preallocation=metadata dsk/vm-hdd.qcow 20G
+
+qemu-system-x86_64 \
+  -machine type=q35 \
+  --enable-kvm \
+  -cpu host \
+  -smp cpus=8 \
+  -m 512M
+  -netdev user,id=net0 \
+  -device e1000,netdev=net0 \
+  -hda dsk/vm-hdd.qcow \
+;
+```
+
+Don't forget to make your script executable!
+```
+$ chmod +x vm-foo
+```
+
+The nice thing about these scripts is that you can freely copy and edit them
+with the standard UNIX command-line tools that you are used to, meaning that
+you can use one VM script as a template for another virtual machine.  Making a
+VM based on a template then becomes as simple as copying a bash script:
+```
+$ cp vm-foo vm-bar
+```
+
+For more information on creating QEMU disk images, see the
+[qemu-img(1)](https://linux.die.net/man/1/qemu-img) man page.
+
+### QEMU's Advanced Features
+QEMU is a capable of emulating foreign CPU architectures, as well as working in
+conjunction with a hypervisor to perform fully-accelerated, near
+native-performance virtualization.  Some of the supported architectures for
+full-system emulation are:
+
+- Alpha
+- Altera Nios II
+- ARM
+- Axis ETRAX CRIS
+- HP PA-RISC
+- i386/x86
+- IBM System/390
+- Microblaze (big and little endian)
+- MIPS (big and little)
+- MIPS64 (big and little)
+- Motorola 68000
+- Moxie
+- OpenRISC 1k (IP core for FPGAs)
+- PowerPC
+- PowerPC 64 (big and little)
+- RISC V
+- RISC V 64
+- SuperH SH-4
+- SPARC and SPARC32 Plus
+- SPARC64
+- TILE-Gx
+- Xtensa
+
+Some of its other features include:
+
+- Support for the Intel HAXM, Linux KVM, and Xen hypervisors
+- PCIe passthrough
+- attaching physical disks to VMs
+- USB passthrough
+- network block devices
+- importing and converting disks from other formats
+- command-line interactive monitor
+- VNC support
+- multiple virtual VGA adapters and video modes
+- tap/tun support (bridging to actual network interfaces on the host)
+
+*Stay tuned for more!*