From 6a288243c1f80a578f14741a69e869784f4d7d20 Mon Sep 17 00:00:00 2001
From: Nicolas Stalder <n@stalder.io>
Date: Thu, 7 Mar 2019 01:24:43 +0100
Subject: [PATCH] Add Makefile for installing a HID gadget

The Makefile has targets for building, installing and uninstalling a HID
gadget which acts as FIDO2 authenticator.

Tested on Ubuntu 18.04 but should work on other distros as well. The
only assumption being made is that kernel source is available at
/usr/src/linux-source-$(KERNEL_VERSION).tar.bz2. A possible improvement
would be to have a configure script which finds the correct kernel
source archive.
---
 tools/gadgetfs/Makefile | 65 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 65 insertions(+)
 create mode 100644 tools/gadgetfs/Makefile

diff --git a/tools/gadgetfs/Makefile b/tools/gadgetfs/Makefile
new file mode 100644
index 0000000..a9beca3
--- /dev/null
+++ b/tools/gadgetfs/Makefile
@@ -0,0 +1,65 @@
+TOP := $(shell dirname $(realpath $(lastword $(MAKEFILE_LIST))))
+KERNEL_FULL_VERSION := $(shell uname -r)
+KERNEL_VERSION := $(shell uname -r | grep -o "^[^-]*")
+KERNEL_MAJOR := $(shell uname -r | cut -d. -f1)
+KERNEL_MINOR := $(shell uname -r | cut -d. -f2)
+
+MANUFACTURER = "Solo"
+SERIAL = "1234567890"
+IDVENDOR = "0x0483"
+IDPRODUCT = "0xa2ca"
+PRODUCT = "Solo Software Authenticator"
+CONFIGFS = /sys/kernel/config
+CONFIGFS_FIDO2 = $(CONFIGFS)/usb_gadget/fido2
+
+obj-m := dummy_hcd.o
+KVERSION := $(shell uname -r)
+SHELL := /bin/bash
+
+all: dummy_hcd.ko
+
+install: dummy_hcd.ko
+	modprobe libcomposite
+	insmod dummy_hcd.ko
+	mkdir -p $(CONFIGFS_FIDO2)
+	mkdir -p $(CONFIGFS_FIDO2)/configs/c.1
+	mkdir -p $(CONFIGFS_FIDO2)/functions/hid.usb0
+	echo 0 > $(CONFIGFS_FIDO2)/functions/hid.usb0/protocol
+	echo 0 > $(CONFIGFS_FIDO2)/functions/hid.usb0/subclass
+	echo 64 > $(CONFIGFS_FIDO2)/functions/hid.usb0/report_length
+	echo -ne "\x06\xd0\xf1\x09\x01\xa1\x01\x09\x20\x15\x00\x26\xff\x00\x75\x08\x95\x40\x81\x02\x09\x21\x15\x00\x26\xff\x00\x75\x08\x95\x40\x91\x02\xc0" > $(CONFIGFS_FIDO2)/functions/hid.usb0/report_desc
+	mkdir $(CONFIGFS_FIDO2)/strings/0x409
+	mkdir $(CONFIGFS_FIDO2)/configs/c.1/strings/0x409
+	echo $(IDPRODUCT) > $(CONFIGFS_FIDO2)/idProduct
+	echo $(IDVENDOR) > $(CONFIGFS_FIDO2)/idVendor
+	echo $(SERIAL) > $(CONFIGFS_FIDO2)/strings/0x409/serialnumber
+	echo $(MANUFACTURER) > $(CONFIGFS_FIDO2)/strings/0x409/manufacturer
+	echo $(PRODUCT) > $(CONFIGFS_FIDO2)/strings/0x409/product
+	echo "Configuration 1" > $(CONFIGFS_FIDO2)/configs/c.1/strings/0x409/configuration
+	echo 120 > $(CONFIGFS_FIDO2)/configs/c.1/MaxPower
+	ln -s $(CONFIGFS_FIDO2)/functions/hid.usb0 $(CONFIGFS_FIDO2)/configs/c.1
+	echo "dummy_udc.0" > $(CONFIGFS_FIDO2)/UDC
+
+uninstall:
+	echo "" > $(CONFIGFS_FIDO2)/UDC
+	rm $(CONFIGFS_FIDO2)/configs/c.1/hid.usb0
+	rmdir $(CONFIGFS_FIDO2)/configs/c.1/strings/0x409
+	rmdir $(CONFIGFS_FIDO2)/configs/c.1
+	rmdir $(CONFIGFS_FIDO2)/functions/hid.usb0
+	rmdir $(CONFIGFS_FIDO2)/strings/0x409
+	rmdir $(CONFIGFS_FIDO2)
+	rmmod dummy_hcd.ko
+
+dummy_hcd.ko: dummy_hcd.c
+	$(MAKE) -C /lib/modules/$(KERNEL_FULL_VERSION)/build M=$(TOP) modules
+
+dummy_hcd.c: /usr/src/linux-source-$(KERNEL_VERSION).tar.bz2
+	tar -xvf $^ linux-source-$(KERNEL_VERSION)/drivers/usb/gadget/udc/dummy_hcd.c
+	cp linux-source-$(KERNEL_VERSION)/drivers/usb/gadget/udc/dummy_hcd.c $@
+
+clean:
+	$(MAKE) -C /lib/modules/$(KERNEL_FULL_VERSION)/build M=$(TOP) clean
+	rm -rf linux-source-$(KERNEL_VERSION)
+	rm -f dummy_hcd.c
+
+