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106 commits

Author SHA1 Message Date
Shawn O. Pearce 34b6cb8bb0 http-backend: Protect GIT_PROJECT_ROOT from /../ requests
Eons ago HPA taught git-daemon how to protect itself from /../
attacks, which Junio brought back into service in d79374c7b5
("daemon.c and path.enter_repo(): revamp path validation").

I did not carry this into git-http-backend as originally we relied
only upon PATH_TRANSLATED, and assumed the HTTP server had done
its access control checks to validate the resolved path was within
a directory permitting access from the remote client.  This would
usually be sufficient to protect a server from requests for its
/etc/passwd file by http://host/smart/../etc/passwd sorts of URLs.

However in 917adc0360 Mark Lodato added GIT_PROJECT_ROOT as an
additional method of configuring the CGI.  When this environment
variable is used the web server does not generate the final access
path and therefore may blindly pass through "/../etc/passwd"
in PATH_INFO under the assumption that "/../" might have special
meaning to the invoked CGI.

Instead of permitting these sorts of malformed path requests, we
now reject them back at the client, with an error message for the
server log.  This matches git-daemon behavior.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-11-09 16:37:33 -08:00
Shawn O. Pearce 92815b3363 Git-aware CGI to provide dumb HTTP transport
http-backend: Fix symbol clash on AIX 5.3

Mike says:

 > > +static void send_file(const char *the_type, const char *name)
 > > +{
 >
 > I think a symbol clash here is responsible for a build breakage in
 > next on AIX 5.3:
 >
 > CC http-backend.o
 > http-backend.c:213: error: conflicting types for `send_file'
 > /usr/include/sys/socket.h:676: error: previous declaration of `send_file'
 > gmake: *** [http-backend.o] Error 1

So we rename the function send_local_file().

Reported-by: Mike Ralphson <mike.ralphson@gmail.com>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-11-09 09:30:01 -08:00
Shawn O. Pearce 5abb013b3d http-backend: Use http.getanyfile to disable dumb HTTP serving
Some repository owners may wish to enable smart HTTP, but disallow
dumb content serving.  Disallowing dumb serving might be because
the owners want to rely upon reachability to control which objects
clients may access from the repository, or they just want to
encourage clients to use the more bandwidth efficient transport.

If http.getanyfile is set to false the backend CGI will return with
'403 Forbidden' when an object file is accessed by a dumb client.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-11-04 17:58:16 -08:00
Mark Lodato 917adc0360 http-backend: add GIT_PROJECT_ROOT environment var
Add a new environment variable, GIT_PROJECT_ROOT, to override the
method of using PATH_TRANSLATED to find the git repository on disk.
This makes it much easier to configure the web server, especially when
the web server's DocumentRoot does not contain the git repositories,
which is the usual case.

Signed-off-by: Mark Lodato <lodatom@gmail.com>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-11-04 17:58:15 -08:00
Shawn O. Pearce 556cfa3b6d Smart fetch and push over HTTP: server side
Requests for $GIT_URL/git-receive-pack and $GIT_URL/git-upload-pack
are forwarded to the corresponding backend process by directly
executing it and leaving stdin and stdout connected to the invoking
web server.  Prior to starting the backend process the HTTP response
headers are sent, thereby freeing the backend from needing to know
about the HTTP protocol.

Requests that are encoded with Content-Encoding: gzip are
automatically inflated before being streamed into the backend.
This is primarily useful for the git-upload-pack backend, which
receives highly repetitive text data from clients that easily
compresses to 50% of its original size.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-11-04 17:58:15 -08:00
Shawn O. Pearce 2f4038ab33 Git-aware CGI to provide dumb HTTP transport
The git-http-backend CGI can be configured into any Apache server
using ScriptAlias, such as with the following configuration:

  LoadModule cgi_module /usr/libexec/apache2/mod_cgi.so
  LoadModule alias_module /usr/libexec/apache2/mod_alias.so
  ScriptAlias /git/ /usr/libexec/git-core/git-http-backend/

Repositories are accessed via the translated PATH_INFO.

The CGI is backwards compatible with the dumb client, allowing all
older HTTP clients to continue to download repositories which are
managed by the CGI.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-11-04 17:58:04 -08:00