SYNOPSIS
--------
[verse]
-'git-http-backend'
+'git http-backend'
DESCRIPTION
-----------
A simple CGI program to serve the contents of a Git repository to Git
clients accessing the repository over http:// and https:// protocols.
+The program supports clients fetching using both the smart HTTP protocol
+and the backwards-compatible dumb HTTP protocol, as well as clients
+pushing using the smart HTTP protocol.
+
+It verifies that the directory has the magic file
+"git-daemon-export-ok", and it will refuse to export any Git directory
+that hasn't explicitly been marked for export this way (unless the
+GIT_HTTP_EXPORT_ALL environmental variable is set).
By default, only the `upload-pack` service is enabled, which serves
-'git-fetch-pack' and 'git-ls-remote' clients, which are invoked from
-'git-fetch', 'git-pull', and 'git-clone'.
+'git fetch-pack' and 'git ls-remote' clients, which are invoked from
+'git fetch', 'git pull', and 'git clone'. If the client is authenticated,
+the `receive-pack` service is enabled, which serves 'git send-pack'
+clients, which is invoked from 'git push'.
+
+SERVICES
+--------
+These services can be enabled/disabled using the per-repository
+configuration file:
+
+http.getanyfile::
+ This serves Git clients older than version 1.6.6 that are unable to use the
+ upload pack service. When enabled, clients are able to read
+ any file within the repository, including objects that are
+ no longer reachable from a branch but are still present.
+ It is enabled by default, but a repository can disable it
+ by setting this configuration item to `false`.
-This is ideally suited for read-only updates, i.e., pulling from
-git repositories.
+http.uploadpack::
+ This serves 'git fetch-pack' and 'git ls-remote' clients.
+ It is enabled by default, but a repository can disable it
+ by setting this configuration item to `false`.
+
+http.receivepack::
+ This serves 'git send-pack' clients, allowing push. It is
+ disabled by default for anonymous users, and enabled by
+ default for users authenticated by the web server. It can be
+ disabled by setting this item to `false`, or enabled for all
+ users, including anonymous users, by setting it to `true`.
URL TRANSLATION
---------------
-'git-http-backend' relies on the invoking web server to perform
-URL to path translation, and store the repository path into the
-PATH_TRANSLATED environment variable. Most web servers will do
-this translation automatically, resolving the suffix after the
-CGI name relative to the server's document root.
+To determine the location of the repository on disk, 'git http-backend'
+concatenates the environment variables PATH_INFO, which is set
+automatically by the web server, and GIT_PROJECT_ROOT, which must be set
+manually in the web server configuration. If GIT_PROJECT_ROOT is not
+set, 'git http-backend' reads PATH_TRANSLATED, which is also set
+automatically by the web server.
EXAMPLES
--------
+All of the following examples map 'http://$hostname/git/foo/bar.git'
+to '/var/www/git/foo/bar.git'.
Apache 2.x::
- To serve all Git repositories contained within the '/git/'
- subdirectory of the DocumentRoot, ensure mod_cgi and
- mod_alias are enabled, and create a ScriptAlias to the CGI:
+ Ensure mod_cgi, mod_alias, and mod_env are enabled, set
+ GIT_PROJECT_ROOT (or DocumentRoot) appropriately, and
+ create a ScriptAlias to the CGI:
++
+----------------------------------------------------------------
+SetEnv GIT_PROJECT_ROOT /var/www/git
+SetEnv GIT_HTTP_EXPORT_ALL
+ScriptAlias /git/ /usr/libexec/git-core/git-http-backend/
+----------------------------------------------------------------
++
+To enable anonymous read access but authenticated write access,
+require authorization for both the initial ref advertisement (which we
+detect as a push via the service parameter in the query string), and the
+receive-pack invocation itself:
+
----------------------------------------------------------------
-ScriptAlias /git/ /usr/libexec/git-core/git-http-backend/git/
+RewriteCond %{QUERY_STRING} service=git-receive-pack [OR]
+RewriteCond %{REQUEST_URI} /git-receive-pack$
+RewriteRule ^/git/ - [E=AUTHREQUIRED:yes]
-<Directory /usr/libexec/git-core>
- Options None
-</Directory>
-<Files /usr/libexec/git-core/git-http-backend>
- Options ExecCGI
-</Files>
+<LocationMatch "^/git/">
+ Order Deny,Allow
+ Deny from env=AUTHREQUIRED
+
+ AuthType Basic
+ AuthName "Git Access"
+ Require group committers
+ Satisfy Any
+ ...
+</LocationMatch>
----------------------------------------------------------------
+
-To require authentication for reads, use a Directory
+If you do not have `mod_rewrite` available to match against the query
+string, it is sufficient to just protect `git-receive-pack` itself,
+like:
++
+----------------------------------------------------------------
+<LocationMatch "^/git/.*/git-receive-pack$">
+ AuthType Basic
+ AuthName "Git Access"
+ Require group committers
+ ...
+</LocationMatch>
+----------------------------------------------------------------
++
+In this mode, the server will not request authentication until the
+client actually starts the object negotiation phase of the push, rather
+than during the initial contact. For this reason, you must also enable
+the `http.receivepack` config option in any repositories that should
+accept a push. The default behavior, if `http.receivepack` is not set,
+is to reject any pushes by unauthenticated users; the initial request
+will therefore report `403 Forbidden` to the client, without even giving
+an opportunity for authentication.
++
+To require authentication for both reads and writes, use a Location
directive around the repository, or one of its parent directories:
+
----------------------------------------------------------------
-<Directory /var/www/git/private>
+<Location /git/private>
AuthType Basic
AuthName "Private Git Access"
Require group committers
...
-</Directory>
+</Location>
+----------------------------------------------------------------
++
+To serve gitweb at the same url, use a ScriptAliasMatch to only
+those URLs that 'git http-backend' can handle, and forward the
+rest to gitweb:
++
+----------------------------------------------------------------
+ScriptAliasMatch \
+ "(?x)^/git/(.*/(HEAD | \
+ info/refs | \
+ objects/(info/[^/]+ | \
+ [0-9a-f]{2}/[0-9a-f]{38} | \
+ pack/pack-[0-9a-f]{40}\.(pack|idx)) | \
+ git-(upload|receive)-pack))$" \
+ /usr/libexec/git-core/git-http-backend/$1
+
+ScriptAlias /git/ /var/www/cgi-bin/gitweb.cgi/
+----------------------------------------------------------------
++
+To serve multiple repositories from different linkgit:gitnamespaces[7] in a
+single repository:
++
+----------------------------------------------------------------
+SetEnvIf Request_URI "^/git/([^/]*)" GIT_NAMESPACE=$1
+ScriptAliasMatch ^/git/[^/]*(.*) /usr/libexec/git-core/git-http-backend/storage.git$1
----------------------------------------------------------------
Accelerated static Apache 2.x::
file contents from the file system directly to the network:
+
----------------------------------------------------------------
-DocumentRoot /var/www
+SetEnv GIT_PROJECT_ROOT /var/www/git
-ScriptAlias /git/ /usr/libexec/git-core/git-http-backend/git/
-Alias /git_static/ /var/www/git/
+AliasMatch ^/git/(.*/objects/[0-9a-f]{2}/[0-9a-f]{38})$ /var/www/git/$1
+AliasMatch ^/git/(.*/objects/pack/pack-[0-9a-f]{40}.(pack|idx))$ /var/www/git/$1
+ScriptAlias /git/ /usr/libexec/git-core/git-http-backend/
+----------------------------------------------------------------
++
+This can be combined with the gitweb configuration:
++
+----------------------------------------------------------------
+SetEnv GIT_PROJECT_ROOT /var/www/git
-RewriteEngine on
-RewriteRule ^/git/(.*/objects/[0-9a-f]{2}/[0-9a-f]{38})$ /git_static/$1 [PT]
-RewriteRule ^/git/(.*/objects/pack/pack-[0-9a-f]{40}.pack)$ /git_static/$1 [PT]
-RewriteRule ^/git/(.*/objects/pack/pack-[0-9a-f]{40}.idx)$ /git_static/$1 [PT]
+AliasMatch ^/git/(.*/objects/[0-9a-f]{2}/[0-9a-f]{38})$ /var/www/git/$1
+AliasMatch ^/git/(.*/objects/pack/pack-[0-9a-f]{40}.(pack|idx))$ /var/www/git/$1
+ScriptAliasMatch \
+ "(?x)^/git/(.*/(HEAD | \
+ info/refs | \
+ objects/info/[^/]+ | \
+ git-(upload|receive)-pack))$" \
+ /usr/libexec/git-core/git-http-backend/$1
+ScriptAlias /git/ /var/www/cgi-bin/gitweb.cgi/
+----------------------------------------------------------------
+
+Lighttpd::
+ Ensure that `mod_cgi`, `mod_alias, `mod_auth`, `mod_setenv` are
+ loaded, then set `GIT_PROJECT_ROOT` appropriately and redirect
+ all requests to the CGI:
++
+----------------------------------------------------------------
+alias.url += ( "/git" => "/usr/lib/git-core/git-http-backend" )
+$HTTP["url"] =~ "^/git" {
+ cgi.assign = ("" => "")
+ setenv.add-environment = (
+ "GIT_PROJECT_ROOT" => "/var/www/git",
+ "GIT_HTTP_EXPORT_ALL" => ""
+ )
+}
+----------------------------------------------------------------
++
+To enable anonymous read access but authenticated write access:
++
+----------------------------------------------------------------
+$HTTP["querystring"] =~ "service=git-receive-pack" {
+ include "git-auth.conf"
+}
+$HTTP["url"] =~ "^/git/.*/git-receive-pack$" {
+ include "git-auth.conf"
+}
+----------------------------------------------------------------
++
+where `git-auth.conf` looks something like:
++
+----------------------------------------------------------------
+auth.require = (
+ "/" => (
+ "method" => "basic",
+ "realm" => "Git Access",
+ "require" => "valid-user"
+ )
+)
+# ...and set up auth.backend here
+----------------------------------------------------------------
++
+To require authentication for both reads and writes:
++
+----------------------------------------------------------------
+$HTTP["url"] =~ "^/git/private" {
+ include "git-auth.conf"
+}
----------------------------------------------------------------
ENVIRONMENT
-----------
-'git-http-backend' relies upon the CGI environment variables set
+'git http-backend' relies upon the CGI environment variables set
by the invoking web server, including:
-* PATH_TRANSLATED
+* PATH_INFO (if GIT_PROJECT_ROOT is set, otherwise PATH_TRANSLATED)
* REMOTE_USER
* REMOTE_ADDR
* CONTENT_TYPE
* QUERY_STRING
* REQUEST_METHOD
+The GIT_HTTP_EXPORT_ALL environmental variable may be passed to
+'git-http-backend' to bypass the check for the "git-daemon-export-ok"
+file in each repository before allowing export of that repository.
+
+The backend process sets GIT_COMMITTER_NAME to '$REMOTE_USER' and
+GIT_COMMITTER_EMAIL to '$\{REMOTE_USER}@http.$\{REMOTE_ADDR\}',
+ensuring that any reflogs created by 'git-receive-pack' contain some
+identifying information of the remote user who performed the push.
+
+All CGI environment variables are available to each of the hooks
+invoked by the 'git-receive-pack'.
+
Author
------
Written by Shawn O. Pearce <spearce@spearce.org>.