Add configuration scripts

Add a generator for the fido2 report descriptor and an initial script
to build and configure the gadget device.  No listener for the packets
yet.

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

5 files changed, 134 insertions, 0 deletions

diff --git a/.gitignore b/.gitignore
index 6c7ceeb..5be79fd 100644
--- a/.gitignore
+++ b/.gitignore
@@ -17,3 +17,4 @@ libtool
 ltmain.sh
 missing
 test-driver
+fido
diff --git a/Makefile.am b/Makefile.am
new file mode 100644
index 0000000..e41caaf
--- /dev/null
+++ b/Makefile.am
@@ -0,0 +1,3 @@
+bin_PROGRAMS=fido
+
+fido_SOURCES=fido.c
diff --git a/configure.ac b/configure.ac
new file mode 100644
index 0000000..4e750eb
--- /dev/null
+++ b/configure.ac
@@ -0,0 +1,8 @@
+AC_INIT(fido2-ctap-gadget, 0.0.1, <James.Bottomley@HansenPartnership.com>)
+AM_INIT_AUTOMAKE([foreign 1.6])
+
+AC_PROG_CC_STDC
+AC_USE_SYSTEM_EXTENSIONS
+AC_SYS_LARGEFILE
+
+AC_OUTPUT([Makefile])
diff --git a/fido.c b/fido.c
new file mode 100644
index 0000000..632e66f
--- /dev/null
+++ b/fido.c
@@ -0,0 +1,49 @@
+/*
+ * Create the FIDO2 report descriptor for a HID gadget
+ *
+ * Copyright (C) 2019 James.Bottomley@HansenPartnership.com
+ *
+ * SPDX-License-Identifier: GPL-2.0-only
+ */
+
+#include <stdio.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdlib.h>
+
+#include <sys/types.h>
+#include <sys/stat.h>
+
+unsigned char report_desc[] = {
+	0x06, 0xd0, 0xf1,	/* UsagePage(FIDO_USAGE_PAGE) */
+	0x09, 0x01,		/* Usage(FIDO_USAGE_CTAPHID) */
+	0xa1, 0x01,		/* Collection(Application) */
+	0x09, 0x20,		/* Usage(FIDO_DATA_IN) */
+	0x19, 0x00,		/* LogicalMin(0) */
+	0x29, 0xff,		/* LogicalMax(FF) */
+	0x75, 0x08,		/* ReportSize(8) */
+	0x95, 0x40,		/* ReportCount(64) */
+	0x81, 0x02,		/* Input(Data, Var, Abs) */
+	0x09, 0x21,		/* Usage(FIDO_DATA_OUT) */
+	0x19, 0x00,		/* LogicalMin(0) */
+	0x29, 0xff,		/* LogicalMax(FF) */
+	0x75, 0x08,		/* ReportSize(8) */
+	0x95, 0x40,		/* ReportCount(64) */
+	0x91, 0x02,		/* Output(Data, Var, Abs) */
+	0xc0,			/* EndCollection */
+};
+
+int
+main(int argc, void *argv[])
+{
+	int fd;
+
+	printf("size is %d\n", sizeof(report_desc));
+	if (argc != 2)
+		exit(0);
+	printf("writing file\n");
+	fd = open(argv[1], O_CREAT|O_TRUNC|O_WRONLY);
+	write (fd, report_desc, sizeof(report_desc));
+
+	return 0;
+}
diff --git a/fido_configfs.sh b/fido_configfs.sh
new file mode 100755
index 0000000..2519261
--- /dev/null
+++ b/fido_configfs.sh
@@ -0,0 +1,73 @@
+#!/bin/bash
+set -x
+
+configdir=/sys/kernel/config/usb_gadget
+dev=fido2
+report_desc=`pwd`/fido
+
+if [ `whoami` != "root" ]; then
+    echo "Must be root to run this script"
+    exit 1;
+fi
+
+if [ ! -f $report_desc ]; then
+    echo "ERROR: $report_desc must exist"
+    exit 1;
+fi
+
+modprobe libcomposite
+# expect systemd to have mounted configfs
+if [ ! -d $configdir ]; then
+    echo "systemd failed to mount $configdir"
+    exit 1;
+fi
+
+cd $configdir
+mkdir $dev
+cd $dev
+##
+# create bogus vendor and product
+##
+echo 0xabcd > idVendor
+echo 0xabcd > idProduct
+##
+# Add identity strings
+##
+mkdir strings/0x409
+echo jejb > strings/0x409/manufacturer
+echo "fido2 ctap" > strings/0x409/product
+echo 12345678 > strings/0x409/serialnumber
+
+##
+# Now make the Config
+##
+mkdir configs/c.1
+# conventional power number
+echo 120 > configs/c.1/MaxPower
+mkdir configs/c.1/strings/0x409
+# should set configuration but HID would override
+
+##
+# now set up the function
+##
+mkdir functions/hid.usb0
+# we're a non boot hid
+echo 0 > functions/hid.usb0/protocol
+echo 0 > functions/hid.usb0/subclass
+##
+# All CTAP protocols require 64 byte reports
+##
+echo 64 > functions/hid.usb0/report_length
+##
+# Set the compiled report descriptor
+##
+$report_desc  functions/hid.usb0/report_desc || exit 1
+
+##
+# now link the config to the interface
+##
+ln -s functions/hid.usb0 configs/c.1/
+modprobe dummy_hcd
+echo "dummy_udc.0" > UDC
+
+