wireproto: define permissions-based routing of HTTPv2 wire protocol
Now that we have a scaffolding for serving version 2 of the HTTP
protocol, let's start implementing it.
A good place to start is URL routing and basic request processing
semantics. We can focus on content types, capabilities detect, etc
later.
Version 2 of the HTTP wire protocol encodes the needed permissions
of the request in the URL path. The reasons for this are documented
in the added documentation. In short, a) it makes it really easy and
fail proof for server administrators to implement path-based
authentication and b) it will enable clients to realize very early in
a server exchange that authentication will be required to complete
the operation. This latter point avoids all kinds of complexity and
problems, like dealing with Expect: 100-continue and clients finding
out later during `hg push` that they need to provide authentication.
This will avoid the current badness where clients send a full bundle,
get an HTTP 403, provide authentication, then retransmit the bundle.
In order to implement command checking, we needed to implement a
protocol handler for the new wire protocol. Our handler is just
small enough to run the code we've implemented.
Tests for the defined functionality have been added.
I very much want to refactor the permissions checking code and define
a better response format. But this can be done later. Nothing is
covered by backwards compatibility at this point.
Differential Revision: https://phab.mercurial-scm.org/D2836
#require unix-permissions no-root
$ hg init t
$ cd t
$ echo foo > a
$ hg add a
$ hg commit -m "1"
$ hg verify
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
1 files, 1 changesets, 1 total revisions
$ chmod -r .hg/store/data/a.i
$ hg verify
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
abort: Permission denied: $TESTTMP/t/.hg/store/data/a.i
[255]
$ chmod +r .hg/store/data/a.i
$ hg verify
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
1 files, 1 changesets, 1 total revisions
$ chmod -w .hg/store/data/a.i
$ echo barber > a
$ hg commit -m "2"
trouble committing a!
abort: Permission denied: $TESTTMP/t/.hg/store/data/a.i
[255]
$ chmod -w .
$ hg diff --nodates
diff -r 2a18120dc1c9 a
--- a/a
+++ b/a
@@ -1,1 +1,1 @@
-foo
+barber
$ chmod +w .
$ chmod +w .hg/store/data/a.i
$ mkdir dir
$ touch dir/a
$ hg status
M a
? dir/a
$ chmod -rx dir
#if no-fsmonitor
(fsmonitor makes "hg status" avoid accessing to "dir")
$ hg status
dir: Permission denied
M a
#endif
Reenable perm to allow deletion:
$ chmod +rx dir
$ cd ..