Tell a server that protocol v1 can be used by sending the http header
'Git-Protocol' with 'version=1' indicating this.
Also teach the apache http server to pass through the 'Git-Protocol'
header as an environment variable 'GIT_PROTOCOL'.
Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
http.c supports HTTP redirects of the form
http://foo/info/refs?service=git-upload-pack
-> http://anything
-> http://bar/info/refs?service=git-upload-pack
(that is to say, as long as the Git part of the path and the query
string is preserved in the final redirect destination, the intermediate
steps can have any URL). However, if one of the intermediate steps
results in an HTTP exception, a confusing "unable to update url base
from redirection" message is printed instead of a Curl error message
with the HTTP exception code.
This was introduced by 2 commits. Commit c93c92f ("http: update base
URLs when we see redirects", 2013-09-28) introduced a best-effort
optimization that required checking if only the "base" part of the URL
differed between the initial request and the final redirect destination,
but it performed the check before any HTTP status checking was done. If
something went wrong, the normal code path was still followed, so this
did not cause any confusing error messages until commit 6628eb4 ("http:
always update the base URL for redirects", 2016-12-06), which taught
http to die if the non-"base" part of the URL differed.
Therefore, teach http to check the HTTP status before attempting to
check if only the "base" part of the URL differed. This commit teaches
http_request_reauth to return early without updating options->base_url
upon an error; the only invoker of this function that passes a non-NULL
"options" is remote-curl.c (through "http_get_strbuf"), which only uses
options->base_url for an informational message in the situations that
this commit cares about (that is, when the return value is not HTTP_OK).
The included test checks that the redirect scheme at the beginning of
this commit message works, and that returning a 502 in the middle of the
redirect scheme produces the correct result. Note that this is different
from the test in commit 6628eb4 ("http: always update the base URL for
redirects", 2016-12-06) in that this commit tests that a Git-shaped URL
(http://.../info/refs?service=git-upload-pack) works, whereas commit
6628eb4 tests that a non-Git-shaped URL
(http://.../info/refs/foo?service=git-upload-pack) does not work (even
though Git is processing that URL) and is an error that is fatal, not
silently swallowed.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Acked-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Transport with dumb http can be fooled into following foreign URLs
that the end user does not intend to, especially with the server
side redirects and http-alternates mechanism, which can lead to
security issues. Tighten the redirection and make it more obvious
to the end user when it happens.
* jk/http-walker-limit-redirect-2.9:
http: treat http-alternates like redirects
http: make redirects more obvious
remote-curl: rename shadowed options variable
http: always update the base URL for redirects
http: simplify update_url_from_redirect
We instruct curl to always follow HTTP redirects. This is
convenient, but it creates opportunities for malicious
servers to create confusing situations. For instance,
imagine Alice is a git user with access to a private
repository on Bob's server. Mallory runs her own server and
wants to access objects from Bob's repository.
Mallory may try a few tricks that involve asking Alice to
clone from her, build on top, and then push the result:
1. Mallory may simply redirect all fetch requests to Bob's
server. Git will transparently follow those redirects
and fetch Bob's history, which Alice may believe she
got from Mallory. The subsequent push seems like it is
just feeding Mallory back her own objects, but is
actually leaking Bob's objects. There is nothing in
git's output to indicate that Bob's repository was
involved at all.
The downside (for Mallory) of this attack is that Alice
will have received Bob's entire repository, and is
likely to notice that when building on top of it.
2. If Mallory happens to know the sha1 of some object X in
Bob's repository, she can instead build her own history
that references that object. She then runs a dumb http
server, and Alice's client will fetch each object
individually. When it asks for X, Mallory redirects her
to Bob's server. The end result is that Alice obtains
objects from Bob, but they may be buried deep in
history. Alice is less likely to notice.
Both of these attacks are fairly hard to pull off. There's a
social component in getting Mallory to convince Alice to
work with her. Alice may be prompted for credentials in
accessing Bob's repository (but not always, if she is using
a credential helper that caches). Attack (1) requires a
certain amount of obliviousness on Alice's part while making
a new commit. Attack (2) requires that Mallory knows a sha1
in Bob's repository, that Bob's server supports dumb http,
and that the object in question is loose on Bob's server.
But we can probably make things a bit more obvious without
any loss of functionality. This patch does two things to
that end.
First, when we encounter a whole-repo redirect during the
initial ref discovery, we now inform the user on stderr,
making attack (1) much more obvious.
Second, the decision to follow redirects is now
configurable. The truly paranoid can set the new
http.followRedirects to false to avoid any redirection
entirely. But for a more practical default, we will disallow
redirects only after the initial ref discovery. This is
enough to thwart attacks similar to (2), while still
allowing the common use of redirects at the repository
level. Since c93c92f30 (http: update base URLs when we see
redirects, 2013-09-28) we re-root all further requests from
the redirect destination, which should generally mean that
no further redirection is necessary.
As an escape hatch, in case there really is a server that
needs to redirect individual requests, the user can set
http.followRedirects to "true" (and this can be done on a
per-server basis via http.*.followRedirects config).
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If a malicious server redirects the initial ref
advertisement, it may be able to leak sha1s from other,
unrelated servers that the client has access to. For
example, imagine that Alice is a git user, she has access to
a private repository on a server hosted by Bob, and Mallory
runs a malicious server and wants to find out about Bob's
private repository.
Mallory asks Alice to clone an unrelated repository from her
over HTTP. When Alice's client contacts Mallory's server for
the initial ref advertisement, the server issues an HTTP
redirect for Bob's server. Alice contacts Bob's server and
gets the ref advertisement for the private repository. If
there is anything to fetch, she then follows up by asking
the server for one or more sha1 objects. But who is the
server?
If it is still Mallory's server, then Alice will leak the
existence of those sha1s to her.
Since commit c93c92f30 (http: update base URLs when we see
redirects, 2013-09-28), the client usually rewrites the base
URL such that all further requests will go to Bob's server.
But this is done by textually matching the URL. If we were
originally looking for "http://mallory/repo.git/info/refs",
and we got pointed at "http://bob/other.git/info/refs", then
we know that the right root is "http://bob/other.git".
If the redirect appears to change more than just the root,
we punt and continue to use the original server. E.g.,
imagine the redirect adds a URL component that Bob's server
will ignore, like "http://bob/other.git/info/refs?dummy=1".
We can solve this by aborting in this case rather than
silently continuing to use Mallory's server. In addition to
protecting from sha1 leakage, it's arguably safer and more
sane to refuse a confusing redirect like that in general.
For example, part of the motivation in c93c92f30 is
avoiding accidentally sending credentials over clear http,
just to get a response that says "try again over https". So
even in a non-malicious case, we'd prefer to err on the side
of caution.
The downside is that it's possible this will break a
legitimate but complicated server-side redirection scheme.
The setup given in the newly added test does work, but it's
convoluted enough that we don't need to care about it. A
more plausible case would be a server which redirects a
request for "info/refs?service=git-upload-pack" to just
"info/refs" (because it does not do smart HTTP, and for some
reason really dislikes query parameters). Right now we
would transparently downgrade to dumb-http, but with this
patch, we'd complain (and the user would have to set
GIT_SMART_HTTP=0 to fetch).
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Tests for "git svn" have been taught to reuse the lib-httpd test
infrastructure when testing the subversion integration that
interacts with subversion repositories served over the http://
protocol.
* ew/git-svn-http-tests:
git svn: migrate tests to use lib-httpd
t/t91*: do not say how to avoid the tests
This allows us to use common test infrastructure and parallelize
the tests. For now, GIT_SVN_TEST_HTTPD=true needs to be set to
enable the SVN HTTP tests because we reuse the same test cases
for both file:// and http:// SVN repositories. SVN_HTTPD_PORT
is no longer honored.
Tested under Apache 2.2 and 2.4 on Debian 7.x (wheezy) and
8.x (jessie), respectively.
Cc: Clemens Buchacher <drizzd@aon.at>
Cc: Michael J Gruber <git@drmicha.warpmail.net>
Signed-off-by: Eric Wong <e@80x24.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Update tests for "http.extraHeaders=<header>" to be portable back
to Apache 2.2 (the original depended on <RequireAll/> which is a
more recent feature).
* js/http-custom-headers:
submodule: ensure that -c http.extraheader is heeded
t5551: make the test for extra HTTP headers more robust
tests: adjust the configuration for Apache 2.2
Lars Schneider noticed that the configuration introduced to test the
extra HTTP headers cannot be used with Apache 2.2 (which is still
actively maintained, as pointed out by Junio Hamano).
To let the tests pass with Apache 2.2 again, let's substitute the
offending <RequireAll> and `expr` by using old school RewriteCond
statements.
As RewriteCond does not allow testing for *non*-matches, we simply match
the desired case first and let it pass by marking the RewriteRule as
'[L]' ("last rule, do not process any other matching RewriteRules after
this"), and then have another RewriteRule that matches all other cases
and lets them fail via '[F]' ("fail").
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Tested-by: Lars Schneider <larsxschneider@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
HTTP transport clients learned to throw extra HTTP headers at the
server, specified via http.extraHeader configuration variable.
* js/http-custom-headers:
http: support sending custom HTTP headers
We introduce a way to send custom HTTP headers with all requests.
This allows us, for example, to send an extra token from build agents
for temporary access to private repositories. (This is the use case that
triggered this patch.)
This feature can be used like this:
git -c http.extraheader='Secret: sssh!' fetch $URL $REF
Note that `curl_easy_setopt(..., CURLOPT_HTTPHEADER, ...)` takes only
a single list, overriding any previous call. This means we have to
collect _all_ of the headers we want to use into a single list, and
feed it to cURL in one shot. Since we already unconditionally set a
"pragma" header when initializing the curl handles, we can add our new
headers to that list.
For callers which override the default header list (like probe_rpc),
we provide `http_copy_default_headers()` so they can do the same
trick.
Big thanks to Jeff King and Junio Hamano for their outstanding help and
patient reviews.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The tests that involve running httpd leaked the system-wide
configuration in /etc/gitconfig to the tested environment.
* jk/test-httpd-config-nosystem:
t/lib-httpd: pass through GIT_CONFIG_NOSYSTEM env
The tests that involve running httpd leaked the system-wide
configuration in /etc/gitconfig to the tested environment.
* jk/test-httpd-config-nosystem:
t/lib-httpd: pass through GIT_CONFIG_NOSYSTEM env
We set GIT_CONFIG_NOSYSTEM in our test scripts so that we do
not accidentally read /etc/gitconfig and have it influence
the outcome of the tests. But when running smart-http tests,
Apache will clean the environment, including this variable,
and the "server" side of our http operations will read it.
You can see this breakage by doing something like:
make
./git config --system http.getanyfile false
make test
which will cause t5561 to fail when it tests the
fallback-to-dumb operation.
We can fix this by instructing Apache to pass through the
variable. Unlike with other variables (e.g., 89c57ab3's
GIT_TRACE), we don't need to set a dummy value to prevent
warnings from Apache. test-lib.sh already makes sure that
GIT_CONFIG_NOSYSTEM is set and exported.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In contrast to apache 2.2, apache 2.4 does not load mod_unixd in its
default configuration (because there are choices). Thus, with the
current config, apache 2.4.10 will not be started and the httpd tests
will not run on distros with default apache config (RedHat type).
Enable mod_unixd to make the httpd tests run. This does not affect
distros negatively which have that config already in their default
(Debian type). httpd tests will run on these before and after this patch.
Signed-off-by: Michael J Gruber <git@drmicha.warpmail.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
By default, libcurl will follow circular http redirects
forever. Let's put a cap on this so that somebody who can
trigger an automated fetch of an arbitrary repository (e.g.,
for CI) cannot convince git to loop infinitely.
The value chosen is 20, which is the same default that
Firefox uses.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Previously, libcurl would follow redirection to any protocol
it was compiled for support with. This is desirable to allow
redirection from HTTP to HTTPS. However, it would even
successfully allow redirection from HTTP to SFTP, a protocol
that git does not otherwise support at all. Furthermore
git's new protocol-whitelisting could be bypassed by
following a redirect within the remote helper, as it was
only enforced at transport selection time.
This patch limits redirects within libcurl to HTTP, HTTPS,
FTP and FTPS. If there is a protocol-whitelist present, this
list is limited to those also allowed by the whitelist. As
redirection happens from within libcurl, it is impossible
for an HTTP redirect to a protocol implemented within
another remote helper.
When the curl version git was compiled with is too old to
support restrictions on protocol redirection, we warn the
user if GIT_ALLOW_PROTOCOL restrictions were requested. This
is a little inaccurate, as even without that variable in the
environment, we would still restrict SFTP, etc, and we do
not warn in that case. But anything else means we would
literally warn every time git accesses an http remote.
This commit includes a test, but it is not as robust as we
would hope. It redirects an http request to ftp, and checks
that curl complained about the protocol, which means that we
are relying on curl's specific error message to know what
happened. Ideally we would redirect to a working ftp server
and confirm that we can clone without protocol restrictions,
and not with them. But we do not have a portable way of
providing an ftp server, nor any other protocol that curl
supports (https is the closest, but we would have to deal
with certificates).
[jk: added test and version warning]
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Apache removes GIT_TRACE from the environment before running
git-http-backend. This can make it hard to debug the server
side of an http session. Let's let it through.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When git is compiled with "-fsanitize=address" (using clang
or gcc >= 4.8), all invocations of git will check for buffer
overflows. This is similar to running with valgrind, except
that it is more thorough (because of the compiler support,
function-local buffers can be checked, too) and runs much
faster (making it much less painful to run the whole test
suite with the checks turned on).
Unlike valgrind, the magic happens at compile-time, so we
don't need the same infrastructure in the test suite that we
did to support --valgrind. But there are two things we can
help with:
1. On some platforms, the leak-detector is on by default,
and causes every invocation of "git init" (and thus
every test script) to fail. Since running git with
the leak detector is pointless, let's shut it off
automatically in the tests, unless the user has already
configured it.
2. When apache runs a CGI, it clears the environment of
unknown variables. This means that the $ASAN_OPTIONS
config doesn't make it to git-http-backend, and it
dies due to the leak detector. Let's mark the variable
as OK for apache to pass.
With these two changes, running
make CC=clang CFLAGS=-fsanitize=address test
works out of the box.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The "--signed" option received by "git push" is first passed to the
transport layer, which the native transport directly uses to notice
that a push certificate needs to be sent. When the transport-helper
is involved, however, the option needs to be told to the helper with
set_helper_option(), and the helper needs to take necessary action.
For the smart-HTTP helper, the "necessary action" involves spawning
the "git send-pack" subprocess with the "--signed" option.
Once the above all gets wired in, the smart-HTTP transport now can
use the push certificate mechanism to authenticate its pushes.
Add a test that is modeled after tests for the native transport in
t5534-push-signed.sh to t5541-http-push-smart.sh. Update the test
Apache configuration to pass GNUPGHOME environment variable through.
As PassEnv would trigger warnings for an environment variable that
is not set, export it from test-lib.sh set to a harmless value when
GnuPG is not being used in the tests.
Note that the added test is deliberately loose and does not check
the nonce in this step. This is because the stateless RPC mode is
inevitably flaky and a nonce that comes back in the actual push
processing is one issued by a different process; if the two
interactions with the server crossed a second boundary, the nonces
will not match and such a check will fail. A later patch in the
series will work around this shortcoming.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
extract_content_type() could not extract a charset parameter if the
parameter is not the first one and there is a whitespace and a following
semicolon just before the parameter. For example:
text/plain; format=fixed ;charset=utf-8
And it also could not handle correctly some other cases, such as:
text/plain; charset=utf-8; format=fixed
text/plain; some-param="a long value with ;semicolons;"; charset=utf-8
Thanks-to: Jeff King <peff@peff.net>
Signed-off-by: Yi EungJun <eungjun.yi@navercorp.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We currently recognize an error message with a content-type
"text/plain; charset=utf-16" as text, but we ignore the
charset parameter entirely. Let's encode it to
log_output_encoding, which is presumably something the
user's terminal can handle.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we get a content-type from curl, we get the whole
header line, including any parameters, and without any
normalization (like downcasing or whitespace) applied.
If we later try to match it with strcmp() or even
strcasecmp(), we may get false negatives.
This could cause two visible behaviors:
1. We might fail to recognize a smart-http server by its
content-type.
2. We might fail to relay text/plain error messages to
users (especially if they contain a charset parameter).
This patch teaches the http code to extract and normalize
just the type/subtype portion of the string. This is
technically passing out less information to the callers, who
can no longer see the parameters. But none of the current
callers cares, and a future patch will add back an
easier-to-use method for accessing those parameters.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since commit 426e70d (remote-curl: show server content on
http errors, 2013-04-05), we relay any text/plain error
messages from the remote server to the user. However, we
never tested it.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Using write_script will set our shebang line appropriately
with $SHELL_PATH. The script that is there now is quite
simple and likely to succeed even with a non-POSIX /bin/sh,
but it does not hurt to be defensive.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The httpd server we set up to test git's http client code
knows about a single account, in which both the username and
password are "user@host" (the unusual use of the "@" here is
to verify that we handle the character correctly when URL
escaped).
This means that we may miss a certain class of errors in
which the username and password are mixed up internally by
git. We can make our tests more robust by having distinct
values for the username and password.
In addition to tweaking the server passwd file and the
client URL, we must teach the "askpass" harness to accept
multiple values. As a bonus, this makes the setup of some
tests more obvious; when we are expecting git to ask
only about the password, we can seed the username askpass
response with a bogus value.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Handle the case where http transport gets redirected during the
authorization request better.
* jk/http-auth-redirects:
http.c: Spell the null pointer as NULL
remote-curl: rewrite base url from info/refs redirects
remote-curl: store url as a strbuf
remote-curl: make refs_url a strbuf
http: update base URLs when we see redirects
http: provide effective url to callers
http: hoist credential request out of handle_curl_result
http: refactor options to http_get_*
http_request: factor out curlinfo_strbuf
http_get_file: style fixes
For efficiency and security reasons, an earlier commit in
this series taught http_get_* to re-write the base url based
on redirections we saw while making a specific request.
This commit wires that option into the info/refs request,
meaning that a redirect from
http://example.com/foo.git/info/refs
to
https://example.com/bar.git/info/refs
will behave as if "https://example.com/bar.git" had been
provided to git in the first place.
The tests bear some explanation. We introduce two new
hierearchies into the httpd test config:
1. Requests to /smart-redir-limited will work only for the
initial info/refs request, but not any subsequent
requests. As a result, we can confirm whether the
client is re-rooting its requests after the initial
contact, since otherwise it will fail (it will ask for
"repo.git/git-upload-pack", which is not redirected).
2. Requests to smart-redir-auth will redirect, and require
auth after the redirection. Since we are using the
redirected base for further requests, we also update
the credential struct, in order not to mislead the user
(or credential helpers) about which credential is
needed. We can therefore check the GIT_ASKPASS prompts
to make sure we are prompting for the new location.
Because we have neither multiple servers nor https
support in our test setup, we can only redirect between
paths, meaning we need to turn on
credential.useHttpPath to see the difference.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
HTTP servers may send Set-Cookie headers in a response and expect them
to be set on subsequent requests. By default, libcurl behavior is to
store such cookies in memory and reuse them across requests within a
single session. However, it may also make sense, depending on the
server and the cookies, to store them across sessions. Provide users
an option to enable this behavior, writing cookies out to the same
file specified in http.cookiefile.
Signed-off-by: Dave Borowitz <dborowitz@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* jk/apache-test-for-2.4:
lib-httpd/apache.conf: check version only after mod_version loads
t/lib-httpd/apache.conf: configure an MPM module for apache 2.4
t/lib-httpd/apache.conf: load compat access module in apache 2.4
t/lib-httpd/apache.conf: load extra auth modules in apache 2.4
t/lib-httpd/apache.conf: do not use LockFile in apache >= 2.4
Commit 0442743 introduced an <IfVersion> directive near the
top of the apache config file. However, at that point we
have not yet checked for and loaded the mod_version module.
This means that the directive will behave oddly if
mod_version is dynamically loaded, failing to match when it
should.
We can fix this by moving the whole block below the
LoadModule directive for mod_version.
Reported-by: Brian Gernhardt <brian@gernhardtsoftware.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Versions of Apache before 2.4 always had a "MultiProcessing
Module" (MPM) statically built in, which manages the worker
threads/processes. We do not care which one, as it is
largely a performance issue, and we put only a light load on
the server during our testing.
As of Apache 2.4, the MPM module is loadable just like any
other module, but exactly one such module must be loaded. On
a system where the MPMs are compiled dynamically (e.g.,
Debian unstable), this means that our test Apache server
will not start unless we provide the appropriate
configuration.
Unfortunately, we do not actually know which MPM modules are
available or appropriate for the system on which the tests
are running. This patch picks the "prefork" module, as it
is likely to be available on all Unix-like systems.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In apache 2.4, the "Order" directive has gone away in favor
of a new system in mod_authz_host. However, since we want
our config file to remain compatible across multiple Apache
versions, we can use mod_access_compat to keep using the
older style.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In apache 2.4, the "Auth*" and "Require" directives have
moved into the authn_core and authz_core modules,
respectively.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The LockFile directive from earlier versions of apache has
been replaced by the Mutex directive. The latter seems to
give sane defaults and does not need any specific
customization, so we can get away with just adding a version
check to the use of LockFile.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Improve documentation to illustrate "push authenticated, fetch
anonymous" configuration for smart HTTP servers.
* jk/doc-http-backend:
doc/http-backend: match query-string in apache half-auth example
doc/http-backend: give some lighttpd config examples
doc/http-backend: clarify "half-auth" repo configuration
When setting up a "half-auth" repository in which reads can
be done anonymously but writes require authentication, it is
best if the server can require authentication for both the
ref advertisement and the actual receive-pack POSTs. This
alleviates the need for the admin to set http.receivepack in
the repositories, and means that the client is challenged
for credentials immediately, instead of partway through the
push process (and git clients older than v1.7.11.7 had
trouble handling these challenges).
Since detecting a push during the ref advertisement requires
matching the query string, and this is non-trivial to do in
Apache, we have traditionally punted and instructed users to
just protect "/git-receive-pack$". This patch provides the
mod_rewrite recipe to actually match the ref advertisement,
which is preferred.
While we're at it, let's add the recipe to our test scripts
so that we can be sure that it works, and doesn't get broken
(either by our changes or by changes in Apache).
Signed-off-by: Jeff King <peff@peff.net>
Acked-by: Jakub Narębski <jnareb@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Filter the list of refs returned via the dumb HTTP protocol according
to the active namespace, consistent with other clients of the
upload-pack service.
Signed-off-by: John Koleszar <jkoleszar@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Before parsing a suspected smart-HTTP response verify the returned
Content-Type matches the standard. This protects a client from
attempting to process a payload that smells like a smart-HTTP
server response.
JGit has been doing this check on all responses since the dawn of
time. I mistakenly failed to include it in git-core when smart HTTP
was introduced. At the time I didn't know how to get the Content-Type
from libcurl. I punted, meant to circle back and fix this, and just
plain forgot about it.
Signed-off-by: Shawn Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Fixes fetch from servers that ask for auth only during the actual
packing phase. This is not really a recommended configuration, but it
cleans up the code at the same time.
* jk/maint-http-half-auth-fetch:
remote-curl: retry failed requests for auth even with gzip
remote-curl: hoist gzip buffer size to top of post_rpc
Commit b81401c taught the post_rpc function to retry the
http request after prompting for credentials. However, it
did not handle two cases:
1. If we have a large request, we do not retry. That's OK,
since we would have sent a probe (with retry) already.
2. If we are gzipping the request, we do not retry. That
was considered OK, because the intended use was for
push (e.g., listing refs is OK, but actually pushing
objects is not), and we never gzip on push.
This patch teaches post_rpc to retry even a gzipped request.
This has two advantages:
1. It is possible to configure a "half-auth" state for
fetching, where the set of refs and their sha1s are
advertised, but one cannot actually fetch objects.
This is not a recommended configuration, as it leaks
some information about what is in the repository (e.g.,
an attacker can try brute-forcing possible content in
your repository and checking whether it matches your
branch sha1). However, it can be slightly more
convenient, since a no-op fetch will not require a
password at all.
2. It future-proofs us should we decide to ever gzip more
requests.
Signed-off-by: Jeff King <peff@peff.net>
Pushing to smart HTTP server with recent Git fails without having
the username in the URL to force authentication, if the server is
configured to allow GET anonymously, while requiring authentication
for POST.
* jk/maint-http-half-auth-push:
http: prompt for credentials on failed POST
http: factor out http error code handling
t: test http access to "half-auth" repositories
t: test basic smart-http authentication
t/lib-httpd: recognize */smart/* repos as smart-http
t/lib-httpd: only route auth/dumb to dumb repos
t5550: factor out http auth setup
t5550: put auth-required repo in auth/dumb
Some sites set up http access to repositories such that
fetching is anonymous and unauthenticated, but pushing is
authenticated. While there are multiple ways to do this, the
technique advertised in the git-http-backend manpage is to
block access to locations matching "/git-receive-pack$".
Let's emulate that advice in our test setup, which makes it
clear that this advice does not actually work.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We do not currently test authentication for smart-http repos
at all. Part of the infrastructure to do this is recognizing
that auth/smart is indeed a smart-http repo.
The current apache config recognizes only "^/smart/*" as
smart-http. Let's instead treat anything with /smart/ in the
URL as smart-http. This is obviously a stupid thing to do
for a real production site, but for our test suite we know
that our repositories will not have this magic string in the
name.
Note that we will route /foo/smart/bar.git directly to
git-http-backend/bar.git; in other words, everything before
the "/smart/" is irrelevant to finding the repo on disk (but
may impact apache config, for example by triggering auth
checks).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Our test apache config points all of auth/ directly to the
on-disk repositories via an Alias directive. This works fine
because everything authenticated is currently in auth/dumb,
which is a subset. However, this would conflict with a
ScriptAlias for auth/smart (which will come in future
patches), so let's narrow the Alias.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Running the http tests with valgrind does not work for two
reasons:
1. Apache complains about following the symbolic link from
git-http-backend to valgrind.sh.
2. Apache does not pass through the GIT_VALGRIND variable
to the backend CGI.
This patch fixes both problems. Unfortunately, there is a
slight hack we need to handle passing environment variables
through Apache. If we just tell it:
PassEnv GIT_VALGRIND
then Apache will complain when GIT_VALGRIND is not set. If
we try:
SetEnv GIT_VALGRIND ${GIT_VALGRIND}
then when GIT_VALGRIND is not set, it will pass through the
literal "${GIT_VALGRIND}". Instead, we now unconditionally
pass through GIT_VALGRIND from lib-httpd.sh into apache,
even if it is empty.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The http-backend program sets default GIT_COMMITTER_NAME and
GIT_COMMITTER_EMAIL variables based on the REMOTE_USER and
REMOTE_ADDR variables provided by the webserver. However, it
unconditionally overwrites any existing GIT_COMMITTER
variables, which may have been customized by site-specific
code in the webserver (or in a script wrapping http-backend).
Let's leave those variables intact if they already exist,
assuming that any such configuration was intentional. There
is a slight chance of a regression if somebody has set
GIT_COMMITTER_* for the entire webserver, not intending it
to leak through http-backend. We could protect against this
by passing the information in alternate variables. However,
it seems unlikely that anyone will care about that
regression, and there is value in the simplicity of using
the common variable names that are used elsewhere in git.
While we're tweaking the environment-handling in
http-backend, let's switch it to use argv_array to handle
the list of variables. That makes the memory management much
simpler.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We don't currently test this case at all, and instead just
test the DAV mechanism over an unauthenticated push. That
isn't very realistic, as most people will want to
authenticate pushes.
Two of the tests expect_failure as they reveal bugs:
1. Pushing without a username in the URL fails to ask for
credentials when we get an HTTP 401. This has always
been the case, but it would be nice if it worked like
smart-http.
2. Pushing with a username fails to ask for the password
since 986bbc0 (http: don't always prompt for password,
2011-11-04). This is a severe regression in v1.7.8, as
authenticated push-over-DAV is now totally unusable
unless you have credentials in your .netrc.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* gc/http-with-non-ascii-username-url:
Fix username and password extraction from HTTP URLs
t5550: test HTTP authentication and userinfo decoding
Conflicts:
t/lib-httpd/apache.conf
Add a test for HTTP authentication and proper percent-decoding of the
userinfo (username and password) part of the URL.
Signed-off-by: Gabriel Corona <gabriel.corona@enst-bretagne.fr>
Acked-by: Tay Ray Chuan <rctay89@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
