git-http-backend(1) — Linux manual page


GIT-HTTP-BACKEND(1)            Git Manual            GIT-HTTP-BACKEND(1)

NAME         top

       git-http-backend - Server side implementation of Git over HTTP

SYNOPSIS         top

       git http-backend

DESCRIPTION         top

       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 also supports Git’s more-efficient "v2" protocol if
       properly configured; see the discussion of GIT_PROTOCOL in the
       ENVIRONMENT section below.

       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 environment 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. If the client is
       authenticated, the receive-pack service is enabled, which serves
       git send-pack clients, which is invoked from git push.

SERVICES         top

       These services can be enabled/disabled using the per-repository
       configuration file:

           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 value to false.

           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 value to false.

           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.


       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

EXAMPLES         top

       All of the following examples map
       http://$hostname/git/foo/bar.git to /var/www/git/foo/bar.git.

       Apache 2.x
           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/

               # This is not strictly necessary using Apache and a modern version of
               # git-http-backend, as the webserver will pass along the header in the
               # environment as HTTP_GIT_PROTOCOL, and http-backend will copy that into
               # GIT_PROTOCOL. But you may need this line (or something similar if you
               # are using a different webserver), or if you want to support older Git
               # versions that did not do that copying.
               # Having the webserver set up GIT_PROTOCOL is perfectly fine even with
               # modern versions (and will take precedence over HTTP_GIT_PROTOCOL,
               # which means it can be used to override the client's request).
               SetEnvIf Git-Protocol ".*" GIT_PROTOCOL=$0

           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:

               RewriteCond %{QUERY_STRING} service=git-receive-pack [OR]
               RewriteCond %{REQUEST_URI} /git-receive-pack$
               RewriteRule ^/git/ - [E=AUTHREQUIRED:yes]

               <LocationMatch "^/git/">
                       Order Deny,Allow
                       Deny from env=AUTHREQUIRED

                       AuthType Basic
                       AuthName "Git Access"
                       Require group committers
                       Satisfy Any

           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

           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:

               <Location /git/private>
                       AuthType Basic
                       AuthName "Private Git Access"
                       Require group committers

           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))$" \

               ScriptAlias /git/ /var/www/cgi-bin/gitweb.cgi/

           To serve multiple repositories from different
           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
           Similar to the above, but Apache can be used to return static
           files that are stored on disk. On many systems this may be
           more efficient as Apache can ask the kernel to copy the file
           contents from the file system directly to the network:

               SetEnv GIT_PROJECT_ROOT /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

               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/$1
               ScriptAliasMatch \
                       "(?x)^/git/(.*/(HEAD | \
                                       info/refs | \
                                       objects/info/[^/]+ | \
                                       git-(upload|receive)-pack))$" \
               ScriptAlias /git/ /var/www/cgi-bin/gitweb.cgi/

           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

               $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         top

       git http-backend relies upon the CGI environment variables set by
       the invoking web server, including:

       •   PATH_INFO (if GIT_PROJECT_ROOT is set, otherwise

       •   REMOTE_USER

       •   REMOTE_ADDR

       •   CONTENT_TYPE

       •   QUERY_STRING


       The GIT_HTTP_EXPORT_ALL environment 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 GIT_HTTP_MAX_REQUEST_BUFFER environment variable (or the
       http.maxRequestBuffer config option) may be set to change the
       largest ref negotiation request that git will handle during a
       fetch; any fetch requiring a larger buffer will not succeed. This
       value should not normally need to be changed, but may be helpful
       if you are fetching from a repository with an extremely large
       number of refs. The value can be specified with a unit (e.g.,
       100M for 100 megabytes). The default is 10 megabytes.

       Clients may probe for optional protocol capabilities (like the v2
       protocol) using the Git-Protocol HTTP header. In order to support
       these, the contents of that header must appear in the
       GIT_PROTOCOL environment variable. Most webservers will pass this
       header to the CGI via the HTTP_GIT_PROTOCOL variable, and
       git-http-backend will automatically copy that to GIT_PROTOCOL.
       However, some webservers may be more selective about which
       headers they’ll pass, in which case they need to be configured
       explicitly (see the mention of Git-Protocol in the Apache config
       from the earlier EXAMPLES section).

       The backend process sets GIT_COMMITTER_NAME to $REMOTE_USER and
       ensuring that any reflogs created by git-receive-pack contain
       some identifying information of the remote user who performed the

       All CGI environment variables are available to each of the hooks
       invoked by the git-receive-pack.

GIT         top

       Part of the git(1) suite

COLOPHON         top

       This page is part of the git (Git distributed version control
       system) project.  Information about the project can be found at
       ⟨⟩.  If you have a bug report for this manual
       page, see ⟨⟩.  This page was obtained
       from the project's upstream Git repository
       ⟨⟩ on 2023-12-22.  (At that time,
       the date of the most recent commit that was found in the
       repository was 2023-12-20.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there
       is a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to

Git         2023-12-20            GIT-HTTP-BACKEND(1)

Pages that refer to this page: git(1)git-receive-pack(1)git-upload-pack(1)giteveryday(7)gitnamespaces(7)