bin/git-http-backend-verify

   1 #!/bin/sh
   2 #
   3 # Abort any push early if the pushing user doesn't have any push permissions
   4 # at all.  This avoids unnecessary traffic and unpacked object pollution.
   5 #
   6 # Set GIT_HTTP_BACKEND_BIN to change the default http-backend binary from
   7 # the default of Config.pm $git_http_backend_bin (which itself has a default
   8 # of "/usr/lib/git-core/git-http-backend")
   9 #
  10 # Note that GIT_PROJECT_ROOT must be set to use this script.
  11 #
  12 # Also prevent standard error output from git-http-backend cluttering up the
  13 # server's log unless GIT_HTTP_BACKEND_SHOW_ERRORS is set to a non-empty value.
  14
  15 set -e
  16
  17 . @basedir@/shlib.sh
  18
  19 [ -z "$GIT_HTTP_BACKEND_BIN" ] || cfg_git_http_backend_bin="$GIT_HTTP_BACKEND_BIN"
  20 [ -n "$cfg_git_http_backend_bin" ] ||
  21         cfg_git_http_backend_bin=/usr/lib/git-core/git-http-backend
  22
  23 # This script is called for both fetch and push.
  24 # Only the following conditions trigger a push permissions check:
  25 #
  26 #   1. REQUEST_METHOD=GET
  27 #      and PATH_INFO ends with "/info/refs"
  28 #      and QUERY_STRING has "service=git-receive-pack"
  29 #
  30 #   2. REQUEST_METHOD=POST
  31 #      and PATH_INFO ends with "/git-receive-pack"
  32 #
  33 # Note that there is no check for PATH_INFO being under a certain root as
  34 # it's presumed that GIT_PROJECT_ROOT has been set and so all PATH_INFO
  35 # values are effectively forced under the desired root.
  36 # The project name is, however, extracted and the project directory must exist
  37 # under $cfg_reporoot.
  38
  39 errorhdrs()
  40 {
  41         # A single CR (0x0d) is between the quotes
  42         cr="
"
  43         echo "Status: $1 $2$cr"
  44         echo "Expires: Fri, 01 Jan 1980 00:00:00 GMT$cr"
  45         echo "Pragma: no-cache$cr"
  46         echo "Cache-Control: no-cache, max-age=0, must-revalidate$cr"
  47         echo "Content-Type: text/plain$cr"
  48         echo "$cr"
  49 }
  50
  51 msglines()
  52 {
  53         while [ $# -gt 0 ]; do
  54                 echo "$1"
  55                 shift
  56         done
  57 }
  58
  59 internalerr()
  60 {
  61         errorhdrs 500 "Internal Server Error"
  62         if [ $# -eq 0 ]; then
  63                 msglines "Internal Server Error"
  64                 echo "Internal Server Error" >&2
  65         else
  66                 msglines "$@"
  67                 while [ $# -gt 0 ]; do
  68                         echo "$1" >&2
  69                         shift
  70                 done
  71         fi
  72         exit 0
  73 }
  74
  75 forbidden()
  76 {
  77         errorhdrs 403 Forbidden
  78         if [ $# -eq 0 ]; then
  79                 msglines "Forbidden"
  80         else
  81                 msglines "$@"
  82         fi
  83         exit 0
  84 }
  85
  86 needsauth()
  87 {
  88         errorhdrs 401 "Authorization Required"
  89         if [ $# -eq 0 ]; then
  90                 msglines "Authorization Required"
  91         else
  92                 msglines "$@"
  93         fi
  94         exit 0
  95 }
  96
  97 [ -n "$GIT_PROJECT_ROOT" ] || { internalerr 'GIT_PROJECT_ROOT must be set'; exit 1; }
  98
  99 proj=
 100 needscheck=
 101 pathcheck="${PATH_INFO#/}"
 102 if [ "$REQUEST_METHOD" = "GET" -o "$REQUEST_METHOD" = "HEAD" ]; then
 103         case "$pathcheck" in *"/info/refs")
 104                 case "&$QUERY_STRING&" in *"&service=git-receive-pack&"*)
 105                         needscheck=1
 106                         proj="${pathcheck%/info/refs}"
 107                 esac
 108         esac
 109 elif [ "$REQUEST_METHOD" = "POST" ]; then
 110         case "$pathcheck" in *"/git-receive-pack")
 111                 needscheck=1
 112                 proj="${pathcheck%/git-receive-pack}"
 113         esac
 114 fi
 115
 116 if [ -z "$needscheck" ]; then
 117         if [ -n "$GIT_HTTP_BACKEND_SHOW_ERRORS" ]; then
 118                 exec "$cfg_git_http_backend_bin" "$@"
 119         else
 120                 exec "$cfg_git_http_backend_bin" "$@" 2>/dev/null
 121         fi
 122         internalerr "exec failed: $cfg_git_http_backend_bin"
 123         exit 1
 124 fi
 125
 126 # add a missing trailing .git
 127 case "$proj" in
 128         *.git) :;;
 129         *)
 130                 proj="$proj.git"
 131 esac
 132
 133 dir="$cfg_reporoot/$proj"
 134 if ! [ -d "$dir" ] || ! [ -f "$dir/HEAD" ] || ! [ -d "$dir/objects" ]; then
 135         forbidden
 136         exit 1
 137 fi
 138
 139 projbare="${proj%.git}"
 140
 141 if ! [ -f "$dir/.nofetch" ]; then
 142         forbidden "The $proj project is a mirror and may not be pushed to, sorry"
 143         exit 1
 144 fi
 145
 146 authuser="${REMOTE_USER#/UID=}"
 147 authuuid="${authuser}"
 148 authuser="${authuser%/dnQualifier=*}"
 149 authuuid="${authuuid#$authuser}"
 150 authuuid="${authuuid#/dnQualifier=}"
 151 if [ -z "$authuser" ]; then
 152         needsauth "Only authenticated users may push, sorry"
 153         exit 1
 154 fi
 155
 156 if perl -I@basedir@ -MGirocco::Project -MGirocco::User <<EOT; then :; else
 157         my \$p = Girocco::Project->load('$projbare');
 158         exit 1 unless \$p && \$p->can_user_push('$authuser');
 159         exit 0 if \$Girocco::Config::mob eq 'mob' && '$authuser' eq 'mob';
 160         my \$u = Girocco::User->load('$authuser');
 161         exit 2 unless \$u && \$u->{uuid} eq '$authuuid';
 162         exit 0
 163 EOT
 164         if [ $? -eq 2 ]; then
 165                 forbidden "The user '$authuser' certificate being used is no longer valid." \
 166                         "You may download a new user certificate at $cfg_webadmurl/edituser.cgi"
 167         else
 168                 forbidden "The user '$authuser' does not have push permissions for project '$proj'." \
 169                         "You may adjust push permissions at $cfg_webadmurl/editproj.cgi?name=$proj"
 170         fi
 171         exit 1
 172 fi
 173
 174 if [ -n "$GIT_HTTP_BACKEND_SHOW_ERRORS" ]; then
 175         exec "$cfg_git_http_backend_bin" "$@"
 176 else
 177         exec "$cfg_git_http_backend_bin" "$@" 2>/dev/null
 178 fi
 179 internalerr "exec failed: $cfg_git_http_backend_bin"
 180 exit 1