Dear all,

This series of patches adds exporting device operation to USB/IP.

1. Overview

Exporting devices may not be a new idea. The request and response PDU 
have been defined in tools/usbip/usbip/src/usbip_network.h.
#define OP_EXPORT       0x06
# struct op_export_request
# struct op_export_reply
#define OP_UNEXPORT     0x07
# struct op_unexport_request
# struct op_unexport_reply 

But they have not been used yet. This series adds new operations: 
'connect' and 'disconnect' using these PDUs.

EXISTING) - invites devices from application(vhci)-side
         +------+                                 +------------------+
 device--+ STUB |                                 | application/VHCI |
         +------+                                 +------------------+
 1) usbipd ... start daemon
 = = =
 2) usbip list --local
 3) usbip bind
                    <--- list bound devices ---   4) usbip list --remote
                    <--- import a device ------   5) usbip attach
 = = =
                       X disconnected             6) usbip detach
 7) usbip unbind

NEW) - dedicates devices from device(stb)-side
         +------+                                 +------------------+
 device--+ STUB |                                 | application/VHCI |
         +------+                                 +------------------+
                                              1) usbipa ... start daemon
 = = =
 2) usbip list --local
 3) usbip connect     --- export a device ------>
 = = =
 4) usbip disconnect  --- un-export a device --->

 Bind and unbind are done in connect and disconnect internally.

2. The use cases


In existing way, computers in small distance, having same user account, 
can be easily managed by a same user. Bind in local machine and attach 
in remote machine by the user. The devices can be exporsed 
automatically in the local machine, for example, at strat up. They can 
be attached from remote.

When there are distributes linux nodes with USB devices in internet, 
they are exposed by bind operation at start upr, server behind firewall 
can list and attach the devices.  
 Exposed   +----------+                    +--------+    +--------+
 +------+  |Linux     |+                   |Router, |    |Service |
+|device|--|Controller||-------------------|proxy,  |----|on      |
|+------+  +----------+|                   |firewall|    |Linux   |
+------+    +----------+                   +--------+    +--------+
                                           <--- attach(import)
          USB/IP + WS proxy                           WS proxy + USB/IP


Assuming that a server computer which runs application and VHCI is in a 
server room and device side machines are small distributed nodes 
outside of the server room, the operator of the server compter is 
different form the distributed nodes. The server computer may be in 
unattended operation. In the new way, after the daemon has been 
started, device can be connected with connect command in the 
distributed nodes. If the distributed nodes doesn't have user 
interface, the connect command can be executed from start up procedure.

In another senario to connect devices to a Linux based cloud service 
using WebSocket proxy, it's needed to establish connection from a 
device inside of firewall to a service outside. Exporting is suitable 
for the senario.

       Home/SOHO/Intranet                       Internet  
           +----------+     +--------+                   +--------+
 +------+  |Linux     |+    |Router, |                   |Internet|
+|device|--|Controller||----|proxy,  |-------------------|service |
|+------+  +----------+|    |firewall|                   |on Linux|
+------+    +----------+    +--------+                   +--------+
                   connect(export) -->
          USB/IP + WS proxy                           WS proxy + USB/IP
Device                                            Service 
 sensors ......................................... environment analysis 
 cameras ......................................... monitoring, recording
 ID/biometric readers ............................ authentication

Connection from outside firewall is usually blocked.
So existing import request sent with attach command doesn't work.

# usbipd                 (blocked)|| <--------- # usbip attach

Firewall opens some ports, usually HTTP(80) and HTTPS(443), from inside.
Then export request sent with new connect command works.

# usbip connect  -----------------------------> # usbipa

3. Combination with vUDC

New operations work with vUDC. --device option specifies vUDC mode as 
well as list operaion. With stub, connect and disconnect execute bind 
and unbind internally. With vUDC, they do not execute bind and unbind. 
They are done by UDC interface.

4. Security consideration

Daemons accept following requests form network :
    EXISTING) 'list --remote' and 'attach'
    NEW) 'connect' and 'desconnect'

TCP wrappers allows and/or denies network access. It is enabled when 
the daemons are compiled with ./configure --with-tcp-wrappers.

When the daemons are running with SSL or Secure WebSocket tunneling 
proxy, the proxy can use client authentication with certificate files.

5. Mixed usage

Both existing and new way work in same machines simultaneously. Status 
of devices and ports are controlled in stub and vhci driver.

6. Wording

Adding the new operation, some inconsistnecies in wording are appeared 
in documentation, function name, etc. If needed, they are fixed.

'export' is used for bind and 'exported' is used for bound. They are 
changed to 'make importable' and 'imported' respectively. The words not 
new. For example, in the output of port operation, 'imported devices' 
is already used. They are sorted out.

'client' and 'server' are switched between existing and new operation. 
So, words 'device-side' and 'application-side' are used in 
documentations as needed for clarity. 

Version information

This series is divided from "USB/IP over WebSocket" patch set.
Rest of the set will be sent as another series.

# Recreated based on linux-next 20161012. 
# Fixed checkpatch a warning about symbolic permission.
# Fixed checkpatch warnings about traling space in a document.

# Corrected program name of each daemon which are used in version 
string, info messages and daemon name for tcp wrappers.
# Added description about tcp wrappers in security consideration of 
cover letter.
# Added security consideration for existing requests in 
contradistinction to new requests.
# Recreated based on linux-next 20160928.

# Recreated based on linux-next 20160810.

# Moved a set_nodelay() from usbipd_dev.c to usbipd.c to affect both 
device side and application side daemon.
# Removed redundant blank line at the end of files.

# Divided into smaller patches.
# Excluded low-related patches.
# Improved change log.
# Changed info level logs in usbip_ux.c to debug level logs.
# Added options to vUDC.
# Tested with vUDC. 

# Removed userspace transmission and WebSocket command/daemon.
# Fixed checkpatch errors and warnings.

# Added __rcu annotation to a RCU pointer to clear sparse warnings.
# Corrected a copy to RCU pointer with rcu_rcu_assign_pointer(). 
# Added __user annotations to arguments of read/write method. 
# Added static to some functions which are not called from other files.
# Removed unnecessary EXPORT_SYMBOLs.

# Added vendor/pruduct name conversion to port command.
# Put initial value to pool_head in name.c.
# Fixed list command exception when host option is omitted.
# Fixed exception in case gai_strerror() returns NULL.
# Fixed WebSocket connection close via proxy.
# Fixed to stop WebSocket ping-pong on connection close.
# Removed redundant usbipd daemon option.
# Removed redundant SSL code had not been deleted.
# Removed an unused local variable in WebSocket code.
# Modified C++ reserved word in names.c as same as headers.

# Fixed regression of usbip list --remote

# Coding style for goto err labels are fixed.
# Defined magic numbers for open_hc_device() argument.
# Corrected include .../uapi/linux/usbip_ux.h as <linux/usbip_ux.h>.
# Modified parameter notation in manuals not to use '='.
# Fixed inappropriate version definition in 
# Remved unnecessary COPYING and AUTHORS fil from tools/.../websocket/.
# Added -version-info to libraries in tools/.../src.

# Formatted patches from linux-next.
# Fixed change log word wrapping.
# Removed SSL patches.
# Fixed a bug that vendor and product names are not shown by 'usbws 
list -l' because usbip_names_init() was not called in

Thank you,

Nobuo Iwata <>

*** BLURB HERE ***

Nobuo Iwata (9):
  usbip: exporting devices: modifications to network header
  usbip: exporting devices: modifications to host side libraries
  usbip: exporting devices: new connect operation
  usbip: exporting devices: new disconnect operation
  usbip: exporting devices: modifications to daemon
  usbip: exporting devices: modifications to attach and detach
  usbip: exporting devices: new application-side daemon
  usbip: exporting devices: change to usbip_list.c
  usbip: exporting devices: chage to documenattion

 Documentation/usb/usbip_protocol.txt       | 204 ++++++++++++++--
 tools/usb/usbip/                |   2 +-
 tools/usb/usbip/README                     |  70 ++++--
 tools/usb/usbip/doc/usbip.8                | 136 +++++++++--
 tools/usb/usbip/doc/usbipa.8               |  78 +++++++
 tools/usb/usbip/doc/usbipd.8               |  38 +--
 tools/usb/usbip/libsrc/usbip_host_common.c |   6 +-
 tools/usb/usbip/libsrc/usbip_host_common.h |   8 +-
 tools/usb/usbip/libsrc/vhci_driver.c       | 118 ++++++++--
 tools/usb/usbip/libsrc/vhci_driver.h       |   7 +-
 tools/usb/usbip/src/            |  12 +-
 tools/usb/usbip/src/usbip.c                |  15 +-
 tools/usb/usbip/src/usbip.h                |  10 +-
 tools/usb/usbip/src/usbip_attach.c         |  50 +---
 tools/usb/usbip/src/usbip_bind.c           |   7 +-
 tools/usb/usbip/src/usbip_connect.c        | 228 ++++++++++++++++++
 tools/usb/usbip/src/usbip_detach.c         |  13 +-
 tools/usb/usbip/src/usbip_disconnect.c     | 215 +++++++++++++++++
 tools/usb/usbip/src/usbip_list.c           |  22 +-
 tools/usb/usbip/src/usbip_network.h        |   5 +-
 tools/usb/usbip/src/usbip_unbind.c         |   7 +-
 tools/usb/usbip/src/usbipd.c               | 258 +++------------------
 tools/usb/usbip/src/usbipd.h               |  39 ++++
 tools/usb/usbip/src/usbipd_app.c           | 242 +++++++++++++++++++
 tools/usb/usbip/src/usbipd_dev.c           | 252 ++++++++++++++++++++
 25 files changed, 1639 insertions(+), 403 deletions(-)
 create mode 100644 tools/usb/usbip/doc/usbipa.8
 create mode 100644 tools/usb/usbip/src/usbip_connect.c
 create mode 100644 tools/usb/usbip/src/usbip_disconnect.c
 create mode 100644 tools/usb/usbip/src/usbipd.h
 create mode 100644 tools/usb/usbip/src/usbipd_app.c
 create mode 100644 tools/usb/usbip/src/usbipd_dev.c


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