从调试数据分析USB通信协议——USB存储介质【U盘】(三)
前面一圈分析完了，现在我们来分析一下数据流向，不得不说WireShark在用做嵌入式通信协议上的调试分析时，是个不错的软件。因此接下来我们就用WireShark再来分析一下USB Mass Storge设备，即U盘的枚举过程。首先，我要介绍的是如何安装WireShark来用作USB抓包。整个安装过程几乎都是傻瓜式的下一步操作，而这里我要提一下的是，既然是做USB抓包分析，这个USBPcap是一定要注意勾选的。小编我这里已经安装过了，所以显示已经安装好了。
接下来我们打开WireShark软件可以看到左下角有USBPcap1选项，双击进行设置。
同样，小编我这里还是插入的闪迪CZ80的32GB的U盘。当电脑检测到有U盘插入时，设置界面的右下角就会有相应的设备可以勾选，这里我们勾选上并点击OK。
然后我们就可以点击最上面工具栏那个蓝色的鲨鱼鳍按钮[第三个按钮]，开始捕获数据了。现在我们拔下U盘重新插入。就可以看到U盘插入时设备在枚举过程中的所有数据包了。以下是我们在之前介绍的时候设备枚举的第一条指令，即发送Setup令牌包获取设备描述符的指令。但这里在这些数据的前面，你还会发现WireShark有一个URB的结构在USB数据包的前面，这个实际上是驱动程序内部的一些字段，下面我通过一篇博文对其中的信息做简要的介绍。
地址：http://www.cnblogs.com/tureno/articles/6888794.html
通过以上软件来分析，我们可以很清楚的看到数据在host和device的端点0之间的相互流动，device收发均使用的是端点0。其实这种流动一直保持到了GET MAX LUN (0xfe)这条指令以后，在这条指令以后，我们就会开始使用CBW块来承载SCSI指令进行通信了。这时候device使用的是端点2来接收host的命令，因此，从host视角来看，它是输出端点，同理，device使用端点1回发数据给host，即作为输入端点。
关于U盘的分析到这里我们基本就算结束了，最后我们使用USBlyzer22软件，对我们的U盘进行最后的一波分析，来验证我们上面的分析，有如下截图，这里看看就好，小编我也就不再啰嗦什么了。
|
Connection Status |
Device connected |
|
Current Configuration |
1 |
|
Speed |
High (480 Mbit/s) |
|
Device Address |
1 |
|
Number Of Open Pipes |
2 |
|
Offset |
Field |
Size |
Value |
Description |
|
0 |
bLength |
1 |
12h |
|
|
1 |
bDescriptorType |
1 |
01h |
Device |
|
2 |
bcdUSB |
2 |
0300h |
USB Spec 3.0 |
|
4 |
bDeviceClass |
1 |
00h |
Class info in Ifc Descriptors |
|
5 |
bDeviceSubClass |
1 |
00h |
|
|
6 |
bDeviceProtocol |
1 |
00h |
|
|
7 |
bMaxPacketSize0 |
1 |
09h |
Should be 64 bytes for high-speed devices |
|
8 |
idVendor |
2 |
0781h |
SanDisk Corp. |
|
10 |
idProduct |
2 |
5580h |
|
|
12 |
bcdDevice |
2 |
0010h |
0.10 |
|
14 |
iManufacturer |
1 |
01h |
"SanDisk" |
|
15 |
iProduct |
1 |
02h |
"Extreme" |
|
16 |
iSerialNumber |
1 |
03h |
"AA010314151502060195" |
|
17 |
bNumConfigurations |
1 |
01h |
|
Binary Device Object Store (BOS) Descriptor
|
Offset |
Field |
Size |
Value |
Description |
|
0 |
bLength |
1 |
05h |
|
|
1 |
bDescriptorType |
1 |
0Fh |
Binary Device Object Store (BOS) |
|
2 |
wTotalLength |
2 |
0016h |
|
|
4 |
bNumDeviceCaps |
1 |
02h |
|
Device Capability Descriptor - USB 2.0 Extension
|
Offset |
Field |
Size |
Value |
Description |
|
0 |
bLength |
1 |
07h |
|
|
1 |
bDescriptorType |
1 |
10h |
Device Capability |
|
2 |
bDevCapabilityType |
1 |
02h |
USB 2.0 Extension |
|
3 |
bmAttributes |
4 |
00000002h |
|
|
|
0: Reserved |
|
........ ........ ........ .......0 |
|
|
|
1: Link Power Management |
|
........ ........ ........ ......1. |
Yes |
|
|
31..2: Reserved |
|
00000000 00000000 00000000 000000.. |
|
Device Capability Descriptor - SuperSpeed USB
|
Offset |
Field |
Size |
Value |
Description |
|
0 |
bLength |
1 |
0Ah |
|
|
1 |
bDescriptorType |
1 |
10h |
Device Capability |
|
2 |
bDevCapabilityType |
1 |
03h |
SuperSpeed USB |
|
3 |
bmAttributes |
1 |
00h |
|
|
|
0: Reserved |
|
.......0 |
|
|
|
1: Latency Tolerance Messages |
|
......0. |
No |
|
|
7..2: Reserved |
|
000000.. |
|
|
4 |
wSpeedsSupported |
2 |
000Eh |
|
|
|
0: Low-Speed |
|
........ .......0 |
No |
|
|
1: Full-Speed |
|
........ ......1. |
Yes |
|
|
2: High-Speed |
|
........ .....1.. |
Yes |
|
|
3: Super-Speed |
|
........ ....1... |
Yes |
|
|
15..4: Reserved |
|
00000000 0000.... |
|
|
6 |
bFunctionalitySupport |
1 |
01h |
Full-Speed and above |
|
7 |
bU1DevExitLat |
1 |
07h |
Less than 7 祍 |
|
8 |
wU2DevExitLat |
2 |
0065h |
Less than 101 祍 |
Configuration Descriptor 1 Bus Powered, 400 mA
|
Offset |
Field |
Size |
Value |
Description |
|
0 |
bLength |
1 |
09h |
|
|
1 |
bDescriptorType |
1 |
02h |
Configuration |
|
2 |
wTotalLength |
2 |
002Ch |
|
|
4 |
bNumInterfaces |
1 |
01h |
|
|
5 |
bConfigurationValue |
1 |
01h |
|
|
6 |
iConfiguration |
1 |
00h |
|
|
7 |
bmAttributes |
1 |
80h |
Bus Powered |
|
|
4..0: Reserved |
|
...00000 |
|
|
|
5: Remote Wakeup |
|
..0..... |
No |
|
|
6: Self Powered |
|
.0...... |
No, Bus Powered |
|
|
7: Reserved (set to one) |
|
1....... |
|
|
8 |
bMaxPower |
1 |
32h |
100 mA |
Interface Descriptor 0/0 Mass Storage, 2 Endpoints
|
Offset |
Field |
Size |
Value |
Description |
|
0 |
bLength |
1 |
09h |
|
|
1 |
bDescriptorType |
1 |
04h |
Interface |
|
2 |
bInterfaceNumber |
1 |
00h |
|
|
3 |
bAlternateSetting |
1 |
00h |
|
|
4 |
bNumEndpoints |
1 |
02h |
|
|
5 |
bInterfaceClass |
1 |
08h |
Mass Storage |
|
6 |
bInterfaceSubClass |
1 |
06h |
SCSI Transparent Command Set |
|
7 |
bInterfaceProtocol |
1 |
50h |
Bulk-Only Transport |
|
8 |
iInterface |
1 |
00h |
|
Endpoint Descriptor 81 1 In, Bulk, 1024 bytes
|
Offset |
Field |
Size |
Value |
Description |
|
0 |
bLength |
1 |
07h |
|
|
1 |
bDescriptorType |
1 |
05h |
Endpoint |
|
2 |
bEndpointAddress |
1 |
81h |
1 In |
|
3 |
bmAttributes |
1 |
02h |
Bulk |
|
|
1..0: Transfer Type |
|
......10 |
Bulk |
|
|
7..6: Reserved |
|
00...... |
|
|
4 |
wMaxPacketSize |
2 |
0400h |
1024 bytes |
|
6 |
bInterval |
1 |
00h |
|
|
Offset |
Field |
Size |
Value |
Description |
|
0 |
bLength |
1 |
06h |
|
|
1 |
bDescriptorType |
1 |
30h |
SuperSpeed Endpoint Companion |
|
2 |
bMaxBurst |
1 |
0Fh |
Up to 16 packets at a time |
|
3 |
bmAttributes |
1 |
00h |
|
|
|
4..0: MaxStreams |
|
...00000 |
|
|
|
7..5: Reserved |
|
000..... |
|
|
4 |
wBytesPerInterval |
2 |
0000h |
|
Endpoint Descriptor 02 2 Out, Bulk, 1024 bytes
|
Offset |
Field |
Size |
Value |
Description |
|
0 |
bLength |
1 |
07h |
|
|
1 |
bDescriptorType |
1 |
05h |
Endpoint |
|
2 |
bEndpointAddress |
1 |
02h |
2 Out |
|
3 |
bmAttributes |
1 |
02h |
Bulk |
|
|
1..0: Transfer Type |
|
......10 |
Bulk |
|
|
7..6: Reserved |
|
00...... |
|
|
4 |
wMaxPacketSize |
2 |
0400h |
1024 bytes |
|
6 |
bInterval |
1 |
00h |
|
|
Offset |
Field |
Size |
Value |
Description |
|
0 |
bLength |
1 |
06h |
|
|
1 |
bDescriptorType |
1 |
30h |
SuperSpeed Endpoint Companion |
|
2 |
bMaxBurst |
1 |
0Fh |
Up to 16 packets at a time |
|
3 |
bmAttributes |
1 |
00h |
|
|
|
4..0: MaxStreams |
|
...00000 |
|
|
|
7..5: Reserved |
|
000..... |
|
|
4 |
wBytesPerInterval |
2 |
0000h |
|
这里小编我将相关的资料资源下载链接放在下面：
1.圈圈教你玩usb，一本介绍usb不错的书:http://download.****.net/download/tanjiaqi2554/10049482