[usb_gadget p09] Software updates over HTTP.

Add a /update resource which accepts a new software package (assuming
the hash is correct) and performs an in-place upgrade. To avoid leaving
the device in an unusable state the old version remains running until
the new version starts to accept HTTP connections. At this point the
Tornado I/O loop is running correctly and even if USB functionality
is broken the device should accept another software update to fix it.

BUG=396682
R=rockot@chromium.org,rpaquay@chromium.org,kalman@chromium.org

Review URL: https://codereview.chromium.org/412243002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@285531 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 104 insertions, 1 deletions

diff --git a/tools/usb_gadget/__main__.py b/tools/usb_gadget/__main__.py
index 20998c5..4ca6ad9 100644
--- a/tools/usb_gadget/__main__.py
+++ b/tools/usb_gadget/__main__.py
@@ -25,6 +25,9 @@ def ParseArgs():
   parser.add_argument(
       '--hardware', default='beaglebone-black',
       help='Hardware configuration.')
+  parser.add_argument(
+      '--start-claimed',
+      help='Start with the device claimed by this client.')
   return parser.parse_args()
 
 
@@ -34,6 +37,7 @@ def main():
   server.interface = args.interface
   server.port = args.port
   server.hardware = args.hardware
+  server.claimed_by = args.start_claimed
 
   addrs = netifaces.ifaddresses(server.interface)
   ip_address = addrs[netifaces.AF_INET][0]['addr']
diff --git a/tools/usb_gadget/package.py b/tools/usb_gadget/package.py
index d1a2f2d..069bb14 100755
--- a/tools/usb_gadget/package.py
+++ b/tools/usb_gadget/package.py
@@ -3,13 +3,14 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-"""Utility to package the USB gadget framework.
+"""Utility to package and upload the USB gadget framework.
 """
 
 import argparse
 import hashlib
 import os
 import StringIO
+import urllib2
 import zipfile
 
 
@@ -37,6 +38,27 @@ def MakeZip(directory=None, files=None):
   return content, md5
 
 
+def EncodeBody(filename, buf):
+  return '\r\n'.join([
+      '--foo',
+      'Content-Disposition: form-data; name="file"; filename="{}"'
+      .format(filename),
+      'Content-Type: application/octet-stream',
+      '',
+      buf,
+      '--foo--',
+      ''
+  ])
+
+
+def UploadZip(content, md5, host):
+  filename = 'usb_gadget-{}.zip'.format(md5)
+  req = urllib2.Request(url='http://{}/update'.format(host),
+                        data=EncodeBody(filename, content))
+  req.add_header('Content-Type', 'multipart/form-data; boundary=foo')
+  urllib2.urlopen(req)
+
+
 def main():
   parser = argparse.ArgumentParser(
       description='Package (and upload) the USB gadget framework.')
@@ -50,6 +72,9 @@ def main():
       '--hash-file', type=str, metavar='FILE',
       help='save package hash as FILE')
   parser.add_argument(
+      '--upload', type=str, metavar='HOST[:PORT]',
+      help='upload package to target system')
+  parser.add_argument(
       'files', metavar='FILE', type=str, nargs='*',
       help='source files')
 
@@ -62,6 +87,8 @@ def main():
   if args.hash_file:
     with open(args.hash_file, 'w') as hash_file:
       hash_file.write(md5)
+  if args.upload:
+    UploadZip(content, md5, args.upload)
 
 
 if __name__ == '__main__':
diff --git a/tools/usb_gadget/server.py b/tools/usb_gadget/server.py
index 9f23726..e5aa8b8 100644
--- a/tools/usb_gadget/server.py
+++ b/tools/usb_gadget/server.py
@@ -5,10 +5,16 @@
 """WSGI application to manage a USB gadget.
 """
 
+import datetime
+import hashlib
 import re
+import subprocess
 import sys
+import time
+import urllib2
 
 from tornado import httpserver
+from tornado import ioloop
 from tornado import web
 
 import default_gadget
@@ -20,6 +26,9 @@ chip = None
 claimed_by = None
 default = default_gadget.DefaultGadget()
 gadget = None
+hardware = None
+interface = None
+port = None
 
 
 def SwitchGadget(new_gadget):
@@ -45,6 +54,68 @@ class VersionHandler(web.RequestHandler):
     self.write(version)
 
 
+class UpdateHandler(web.RequestHandler):
+
+  def post(self):
+    fileinfo = self.request.files['file'][0]
+
+    match = VERSION_PATTERN.match(fileinfo['filename'])
+    if match is None:
+      self.write('Filename must contain MD5 hash.')
+      self.set_status(400)
+      return
+
+    content = fileinfo['body']
+    md5sum = hashlib.md5(content).hexdigest()
+    if md5sum != match.group(1):
+      self.write('File hash does not match.')
+      self.set_status(400)
+      return
+
+    filename = 'usb_gadget-{}.zip'.format(md5sum)
+    with open(filename, 'wb') as f:
+      f.write(content)
+
+    args = ['/usr/bin/python', filename,
+            '--interface', interface,
+            '--port', str(port),
+            '--hardware', hardware]
+    if claimed_by is not None:
+      args.extend(['--start-claimed', claimed_by])
+
+    print 'Reloading with version {}...'.format(md5sum)
+
+    global http_server
+    if chip.IsConfigured():
+      chip.Destroy()
+    http_server.stop()
+
+    child = subprocess.Popen(args, close_fds=True)
+
+    while True:
+      child.poll()
+      if child.returncode is not None:
+        self.write('New package exited with error {}.'
+                   .format(child.returncode))
+        self.set_status(500)
+
+        http_server = httpserver.HTTPServer(app)
+        http_server.listen(port)
+        SwitchGadget(gadget)
+        return
+
+      try:
+        f = urllib2.urlopen('http://{}/version'.format(address))
+        if f.getcode() == 200:
+          # Update complete, wait 1 second to make sure buffers are flushed.
+          io_loop = ioloop.IOLoop.instance()
+          io_loop.add_timeout(datetime.timedelta(seconds=1), io_loop.stop)
+          return
+      except urllib2.URLError:
+        pass
+      time.sleep(0.1)
+
+
 class ClaimHandler(web.RequestHandler):
 
   def post(self):
@@ -88,6 +159,7 @@ class ReconnectHandler(web.RequestHandler):
 
 app = web.Application([
     (r'/version', VersionHandler),
+    (r'/update', UpdateHandler),
     (r'/claim', ClaimHandler),
     (r'/unclaim', UnclaimHandler),
     (r'/unconfigure', UnconfigureHandler),