Tryanks/gousb
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Support malformed interface descriptors (#79)

Browse Source 
* Add an invalid interface descriptor to one of the test devices.
* Add a test for getting that interface description.
* Handle the malformed interface/alternate setting descriptors, where
interface/alt numbers don't follow the spec (not 0-based, not contiguous
etc.)

Addresses issue #65.
This commit is contained in:
Sebastian Zagrodzki
2020-04-28 11:32:10 +02:00
committed by GitHub
parent 18f4c1d8a7
commit 9ad54830f4
5 changed files with 49 additions and 18 deletions
Download Patch File Download Diff File Expand all files Collapse all files

18
libusb.go
View File

@@ -271,7 +271,9 @@ func (libusbImpl) getDeviceDesc(d *libusbDevice) (*DeviceDesc, error) {
Cap: int(cfg.bNumInterfaces),
}
c.Interfaces = make([]InterfaceDesc, 0, len(ifaces))
for ifNum, iface := range ifaces {
// a map of interface numbers to a set of alternate settings numbers
hasIntf := make(map[int]map[int]bool)
for _, iface := range ifaces {
if iface.num_altsetting == 0 {
continue
}
@@ -283,7 +285,7 @@ func (libusbImpl) getDeviceDesc(d *libusbDevice) (*DeviceDesc, error) {
Cap: int(iface.num_altsetting),
}
descs := make([]InterfaceSetting, 0, len(alts))
for altNum, alt := range alts {
for _, alt := range alts {
i := InterfaceSetting{
Number: int(alt.bInterfaceNumber),
Alternate: int(alt.bAlternateSetting),
@@ -292,12 +294,16 @@ func (libusbImpl) getDeviceDesc(d *libusbDevice) (*DeviceDesc, error) {
Protocol: Protocol(alt.bInterfaceProtocol),
iInterface: int(alt.iInterface),
}
if ifNum != i.Number {
return nil, fmt.Errorf("config %d interface at index %d has number %d, USB standard states they should be identical", c.Number, ifNum, i.Number)
if hasIntf[i.Number][i.Alternate] {
log.Printf("Device on bus %d address %d offered a descriptor for config %d with two different entries with the same interface number (%d) and the same alternate setting number (%d). gousb will use only the first one.", dev.Bus, dev.Address, c.Number, i.Number, i.Alternate)
continue
}
if altNum != i.Alternate {
return nil, fmt.Errorf("config %d interface %d alternate settings at index %d has number %d, USB standard states they should be identical", c.Number, i.Number, altNum, i.Alternate)
if hasIntf[i.Number] == nil {
hasIntf[i.Number] = make(map[int]bool)
}
hasIntf[i.Number][i.Alternate] = true
var ends []C.struct_libusb_endpoint_descriptor
*(*reflect.SliceHeader)(unsafe.Pointer(&ends)) = reflect.SliceHeader{
Data: uintptr(unsafe.Pointer(alt.endpoint)),