github.com/transparency-dev/armored-witness-os@v0.1.3-0.20240514084412-27eef7325168/trusted_os/usb_hid.go (about)

     1  // Copyright 2022 The Armored Witness OS authors. All Rights Reserved.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package main
    16  
    17  import (
    18  	"encoding/binary"
    19  	"unicode/utf16"
    20  
    21  	"github.com/gsora/fidati"
    22  	"github.com/gsora/fidati/u2fhid"
    23  
    24  	"github.com/usbarmory/tamago/soc/nxp/usb"
    25  
    26  	"github.com/transparency-dev/armored-witness-os/api"
    27  )
    28  
    29  func configureDevice(device *usb.Device, serial string) (err error) {
    30  	// Supported Language Code Zero: English
    31  	device.SetLanguageCodes([]uint16{0x0409})
    32  
    33  	// device descriptor
    34  	device.Descriptor = &usb.DeviceDescriptor{}
    35  	device.Descriptor.SetDefaults()
    36  
    37  	// p5, Table 1-1. Device Descriptor Using Class Codes for IAD,
    38  	// USB Interface Association Descriptor Device Class Code and Use Model.
    39  	device.Descriptor.DeviceClass = 0xef
    40  	device.Descriptor.DeviceSubClass = 0x02
    41  	device.Descriptor.DeviceProtocol = 0x01
    42  
    43  	device.Descriptor.VendorId = api.VendorID
    44  	device.Descriptor.ProductId = api.ProductID
    45  
    46  	device.Descriptor.Device = 0x0001
    47  
    48  	iManufacturer, _ := device.AddString(`WithSecure Foundry`)
    49  	device.Descriptor.Manufacturer = iManufacturer
    50  
    51  	iProduct, _ := device.AddString(`Armory Witness`)
    52  	device.Descriptor.Product = iProduct
    53  
    54  	iSerial, _ := device.AddString(serial)
    55  	device.Descriptor.SerialNumber = iSerial
    56  
    57  	conf := &usb.ConfigurationDescriptor{}
    58  	conf.SetDefaults()
    59  
    60  	if err = device.AddConfiguration(conf); err != nil {
    61  		return
    62  	}
    63  
    64  	// device qualifier
    65  	device.Qualifier = &usb.DeviceQualifierDescriptor{}
    66  	device.Qualifier.SetDefaults()
    67  	device.Qualifier.NumConfigurations = uint8(len(device.Configurations))
    68  
    69  	return
    70  }
    71  
    72  func configureHID(device *usb.Device, ctl *controlInterface) (err error) {
    73  	// Windows blocks non-administrative access to FIDO devices, for this
    74  	// reason we override its standard usage page identifier with a custom
    75  	// one, which grants access.
    76  	binary.LittleEndian.PutUint16(u2fhid.DefaultReport[1:], api.HIDUsagePage)
    77  
    78  	hid, err := u2fhid.NewHandler(ctl)
    79  
    80  	if err != nil {
    81  		return
    82  	}
    83  
    84  	if err = fidati.ConfigureUSB(device.Configurations[0], device, hid); err != nil {
    85  		return
    86  	}
    87  
    88  	numInterfaces := len(device.Configurations[0].Interfaces)
    89  
    90  	// override interface name
    91  	var buf []byte
    92  
    93  	r := []rune("U2FHID interface descriptor")
    94  	u := utf16.Encode([]rune(r))
    95  
    96  	for i := 0; i < len(u); i++ {
    97  		buf = append(buf, byte(u[i]&0xff))
    98  		buf = append(buf, byte(u[i]>>8))
    99  	}
   100  
   101  	interfaceName := device.Configurations[0].Interfaces[numInterfaces-1].Interface
   102  	copy(device.Strings[interfaceName][2:], buf)
   103  
   104  	// avoid conflict with Serial over USB
   105  	device.Configurations[0].Interfaces[numInterfaces-1].Endpoints[usb.OUT].EndpointAddress = 0x03
   106  	device.Configurations[0].Interfaces[numInterfaces-1].Endpoints[usb.IN].EndpointAddress = 0x83
   107  
   108  	if err = hid.AddMapping(api.U2FHID_ARMORY_INF, ctl.Status); err != nil {
   109  		return
   110  	}
   111  
   112  	if err = hid.AddMapping(api.U2FHID_ARMORY_CFG, ctl.Config); err != nil {
   113  		return
   114  	}
   115  
   116  	if err = hid.AddMapping(api.U2FHID_ARMORY_HAB, ctl.HAB); err != nil {
   117  		return
   118  	}
   119  
   120  	if err = hid.AddMapping(api.U2FHID_ARMORY_CONSOLE_LOGS, ctl.ConsoleLogs); err != nil {
   121  		return
   122  	}
   123  	if err = hid.AddMapping(api.U2FHID_ARMORY_CRASH_LOGS, ctl.CrashLogs); err != nil {
   124  		return
   125  	}
   126  
   127  	return
   128  }