tests/test-hgweb-csp.t

ui: add special-purpose atexit functionality

In spite of its longstanding use, Python's built-in atexit code is
not suitable for Mercurial's purposes, for several reasons:

* Handlers run after application code has finished.

* Because of this, the code that runs handlers swallows exceptions
  (since there's no possible stacktrace to associate errors with).
  If we're lucky, we'll get something spat out to stderr (if stderr
  still works), which of course isn't any use in a big deployment
  where it's important that exceptions get logged and aggregated.

* Mercurial's current atexit handlers make unfortunate assumptions
  about process state (specifically stdio) that, coupled with the
  above problems, make it impossible to deal with certain categories
  of error (try "hg status > /dev/full" on a Linux box).

* In Python 3, the atexit implementation is completely hidden, so
  we can't hijack the platform's atexit code to run handlers at a
  time of our choosing.

As a result, here's a perfectly cromulent atexit-like implementation
over which we have control.  This lets us decide exactly when the
handlers run (after each request has completed), and control what
the process state is when that occurs (and afterwards).

#require serve

  $ cat > web.conf << EOF
  > [paths]
  > / = $TESTTMP/*
  > EOF

  $ hg init repo1
  $ cd repo1
  $ touch foo
  $ hg -q commit -A -m initial
  $ cd ..

  $ hg serve -p $HGPORT -d --pid-file=hg.pid --web-conf web.conf
  $ cat hg.pid >> $DAEMON_PIDS

repo index should not send Content-Security-Policy header by default

  $ get-with-headers.py --headeronly localhost:$HGPORT '' content-security-policy etag
  200 Script output follows

static page should not send CSP by default

  $ get-with-headers.py --headeronly localhost:$HGPORT static/mercurial.js content-security-policy etag
  200 Script output follows

repo page should not send CSP by default, should send ETag

  $ get-with-headers.py --headeronly localhost:$HGPORT repo1 content-security-policy etag
  200 Script output follows
  etag: W/"*" (glob)

  $ killdaemons.py

Configure CSP without nonce

  $ cat >> web.conf << EOF
  > [web]
  > csp = script-src https://example.com/ 'unsafe-inline'
  > EOF

  $ hg serve -p $HGPORT -d --pid-file=hg.pid --web-conf web.conf
  $ cat hg.pid > $DAEMON_PIDS

repo index should send Content-Security-Policy header when enabled

  $ get-with-headers.py --headeronly localhost:$HGPORT '' content-security-policy etag
  200 Script output follows
  content-security-policy: script-src https://example.com/ 'unsafe-inline'

static page should send CSP when enabled

  $ get-with-headers.py --headeronly localhost:$HGPORT static/mercurial.js content-security-policy etag
  200 Script output follows
  content-security-policy: script-src https://example.com/ 'unsafe-inline'

repo page should send CSP by default, include etag w/o nonce

  $ get-with-headers.py --headeronly localhost:$HGPORT repo1 content-security-policy etag
  200 Script output follows
  content-security-policy: script-src https://example.com/ 'unsafe-inline'
  etag: W/"*" (glob)

nonce should not be added to html if CSP doesn't use it

  $ get-with-headers.py localhost:$HGPORT repo1/graph/tip | egrep 'content-security-policy|<script'
  <script type="text/javascript" src="/repo1/static/mercurial.js"></script>
  <!--[if IE]><script type="text/javascript" src="/repo1/static/excanvas.js"></script><![endif]-->
  <script type="text/javascript">
  <script type="text/javascript">

Configure CSP with nonce

  $ killdaemons.py
  $ cat >> web.conf << EOF
  > csp = image-src 'self'; script-src https://example.com/ 'nonce-%nonce%'
  > EOF

  $ hg serve -p $HGPORT -d --pid-file=hg.pid --web-conf web.conf
  $ cat hg.pid > $DAEMON_PIDS

nonce should be substituted in CSP header

  $ get-with-headers.py --headeronly localhost:$HGPORT '' content-security-policy etag
  200 Script output follows
  content-security-policy: image-src 'self'; script-src https://example.com/ 'nonce-*' (glob)

nonce should be included in CSP for static pages

  $ get-with-headers.py --headeronly localhost:$HGPORT static/mercurial.js content-security-policy etag
  200 Script output follows
  content-security-policy: image-src 'self'; script-src https://example.com/ 'nonce-*' (glob)

repo page should have nonce, no ETag

  $ get-with-headers.py --headeronly localhost:$HGPORT repo1 content-security-policy etag
  200 Script output follows
  content-security-policy: image-src 'self'; script-src https://example.com/ 'nonce-*' (glob)

nonce should be added to html when used

  $ get-with-headers.py localhost:$HGPORT repo1/graph/tip content-security-policy | egrep 'content-security-policy|<script'
  content-security-policy: image-src 'self'; script-src https://example.com/ 'nonce-*' (glob)
  <script type="text/javascript" src="/repo1/static/mercurial.js"></script>
  <!--[if IE]><script type="text/javascript" src="/repo1/static/excanvas.js"></script><![endif]-->
  <script type="text/javascript" nonce="*"> (glob)
  <script type="text/javascript" nonce="*"> (glob)

hgweb_mod w/o hgwebdir works as expected

  $ killdaemons.py

  $ hg -R repo1 serve -p $HGPORT -d --pid-file=hg.pid --config "web.csp=image-src 'self'; script-src https://example.com/ 'nonce-%nonce%'"
  $ cat hg.pid > $DAEMON_PIDS

static page sends CSP

  $ get-with-headers.py --headeronly localhost:$HGPORT static/mercurial.js content-security-policy etag
  200 Script output follows
  content-security-policy: image-src 'self'; script-src https://example.com/ 'nonce-*' (glob)

nonce included in <script> and headers

  $ get-with-headers.py localhost:$HGPORT graph/tip content-security-policy  | egrep 'content-security-policy|<script'
  content-security-policy: image-src 'self'; script-src https://example.com/ 'nonce-*' (glob)
  <script type="text/javascript" src="/static/mercurial.js"></script>
  <!--[if IE]><script type="text/javascript" src="/static/excanvas.js"></script><![endif]-->
  <script type="text/javascript" nonce="*"> (glob)
  <script type="text/javascript" nonce="*"> (glob)