From 1b854ef4bb15032091a33fed587e5ba6f3e582eb Mon Sep 17 00:00:00 2001
From: Khem Raj <raj.khem@gmail.com>
Date: Wed, 22 May 2019 13:18:55 -0700
Subject: [PATCH] make netgroup support optional

On at least Linux/musl and Linux/uclibc, netgroup
support is not available.  PolKit fails to compile on these systems
for that reason.

This change makes netgroup support conditional on the presence of the
setnetgrent(3) function which is required for the support to work.  If
that function is not available on the system, an error will be returned
to the administrator if unix-netgroup: is specified in configuration.

Fixes bug 50145.

Signed-off-by: A. Wilcox <AWilcox@Wilcox-Tech.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>
Signed-off-by: Adam Duskett <aduskett@gmail.com>
[Thomas: add introspection.m4.]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
---
 buildutil/introspection.m4                    | 142 ++++++++++++++++++
 configure.ac                                  |   2 +-
 src/polkit/polkitidentity.c                   |  16 ++
 src/polkit/polkitunixnetgroup.c               |   3 +
 .../polkitbackendinteractiveauthority.c       |  14 +-
 .../polkitbackendjsauthority.cpp              |   2 +
 test/polkit/polkitidentitytest.c              |   9 +-
 test/polkit/polkitunixnetgrouptest.c          |   3 +
 .../test-polkitbackendjsauthority.c           |   2 +
 9 files changed, 185 insertions(+), 8 deletions(-)
 create mode 100644 buildutil/introspection.m4

diff --git a/buildutil/introspection.m4 b/buildutil/introspection.m4
new file mode 100644
index 0000000..b0ccd68
--- /dev/null
+++ b/buildutil/introspection.m4
@@ -0,0 +1,142 @@
+dnl -*- mode: autoconf -*-
+dnl Copyright 2009 Johan Dahlin
+dnl
+dnl This file is free software; the author(s) gives unlimited
+dnl permission to copy and/or distribute it, with or without
+dnl modifications, as long as this notice is preserved.
+dnl
+
+# serial 1
+
+dnl This is a copy of AS_AC_EXPAND
+dnl
+dnl (C) 2003, 2004, 2005 Thomas Vander Stichele <thomas at apestaart dot org>
+dnl Copying and distribution of this file, with or without modification,
+dnl are permitted in any medium without royalty provided the copyright
+dnl notice and this notice are preserved.
+m4_define([_GOBJECT_INTROSPECTION_AS_AC_EXPAND],
+[
+  EXP_VAR=[$1]
+  FROM_VAR=[$2]
+
+  dnl first expand prefix and exec_prefix if necessary
+  prefix_save=$prefix
+  exec_prefix_save=$exec_prefix
+
+  dnl if no prefix given, then use /usr/local, the default prefix
+  if test "x$prefix" = "xNONE"; then
+    prefix="$ac_default_prefix"
+  fi
+  dnl if no exec_prefix given, then use prefix
+  if test "x$exec_prefix" = "xNONE"; then
+    exec_prefix=$prefix
+  fi
+
+  full_var="$FROM_VAR"
+  dnl loop until it doesn't change anymore
+  while true; do
+    new_full_var="`eval echo $full_var`"
+    if test "x$new_full_var" = "x$full_var"; then break; fi
+    full_var=$new_full_var
+  done
+
+  dnl clean up
+  full_var=$new_full_var
+  AC_SUBST([$1], "$full_var")
+
+  dnl restore prefix and exec_prefix
+  prefix=$prefix_save
+  exec_prefix=$exec_prefix_save
+])
+
+m4_define([_GOBJECT_INTROSPECTION_CHECK_INTERNAL],
+[
+    AC_BEFORE([AC_PROG_LIBTOOL],[$0])dnl setup libtool first
+    AC_BEFORE([AM_PROG_LIBTOOL],[$0])dnl setup libtool first
+    AC_BEFORE([LT_INIT],[$0])dnl setup libtool first
+
+    dnl enable/disable introspection
+    m4_if([$2], [require],
+    [dnl
+        enable_introspection=yes
+    ],[dnl
+        AC_ARG_ENABLE(introspection,
+                  AS_HELP_STRING([--enable-introspection[=@<:@no/auto/yes@:>@]],
+                                 [Enable introspection for this build]),, 
+                                 [enable_introspection=auto])
+    ])dnl
+
+    AC_MSG_CHECKING([for gobject-introspection])
+
+    dnl presence/version checking
+    AS_CASE([$enable_introspection],
+    [no], [dnl
+        found_introspection="no (disabled, use --enable-introspection to enable)"
+    ],dnl
+    [yes],[dnl
+        PKG_CHECK_EXISTS([gobject-introspection-1.0],,
+                         AC_MSG_ERROR([gobject-introspection-1.0 is not installed]))
+        PKG_CHECK_EXISTS([gobject-introspection-1.0 >= $1],
+                         found_introspection=yes,
+                         AC_MSG_ERROR([You need to have gobject-introspection >= $1 installed to build AC_PACKAGE_NAME]))
+    ],dnl
+    [auto],[dnl
+        PKG_CHECK_EXISTS([gobject-introspection-1.0 >= $1], found_introspection=yes, found_introspection=no)
+	dnl Canonicalize enable_introspection
+	enable_introspection=$found_introspection
+    ],dnl
+    [dnl	
+        AC_MSG_ERROR([invalid argument passed to --enable-introspection, should be one of @<:@no/auto/yes@:>@])
+    ])dnl
+
+    AC_MSG_RESULT([$found_introspection])
+
+    dnl expand datadir/libdir so we can pass them to pkg-config
+    dnl and get paths relative to our target directories
+    _GOBJECT_INTROSPECTION_AS_AC_EXPAND(_GI_EXP_DATADIR, "$datadir")
+    _GOBJECT_INTROSPECTION_AS_AC_EXPAND(_GI_EXP_LIBDIR, "$libdir")
+
+    INTROSPECTION_SCANNER=
+    INTROSPECTION_COMPILER=
+    INTROSPECTION_GENERATE=
+    INTROSPECTION_GIRDIR=
+    INTROSPECTION_TYPELIBDIR=
+    if test "x$found_introspection" = "xyes"; then
+       INTROSPECTION_SCANNER=$PKG_CONFIG_SYSROOT_DIR`$PKG_CONFIG --variable=g_ir_scanner gobject-introspection-1.0`
+       INTROSPECTION_COMPILER=$PKG_CONFIG_SYSROOT_DIR`$PKG_CONFIG --variable=g_ir_compiler gobject-introspection-1.0`
+       INTROSPECTION_GENERATE=$PKG_CONFIG_SYSROOT_DIR`$PKG_CONFIG --variable=g_ir_generate gobject-introspection-1.0`
+       INTROSPECTION_GIRDIR=`$PKG_CONFIG --define-variable=datadir="${_GI_EXP_DATADIR}" --variable=girdir gobject-introspection-1.0`
+       INTROSPECTION_TYPELIBDIR="$($PKG_CONFIG --define-variable=libdir="${_GI_EXP_LIBDIR}" --variable=typelibdir gobject-introspection-1.0)"
+       INTROSPECTION_CFLAGS=`$PKG_CONFIG --cflags gobject-introspection-1.0`
+       INTROSPECTION_LIBS=`$PKG_CONFIG --libs gobject-introspection-1.0`
+       INTROSPECTION_MAKEFILE=$PKG_CONFIG_SYSROOT_DIR`$PKG_CONFIG --variable=datadir gobject-introspection-1.0`/gobject-introspection-1.0/Makefile.introspection
+    fi
+    AC_SUBST(INTROSPECTION_SCANNER)
+    AC_SUBST(INTROSPECTION_COMPILER)
+    AC_SUBST(INTROSPECTION_GENERATE)
+    AC_SUBST(INTROSPECTION_GIRDIR)
+    AC_SUBST(INTROSPECTION_TYPELIBDIR)
+    AC_SUBST(INTROSPECTION_CFLAGS)
+    AC_SUBST(INTROSPECTION_LIBS)
+    AC_SUBST(INTROSPECTION_MAKEFILE)
+
+    AM_CONDITIONAL(HAVE_INTROSPECTION, test "x$found_introspection" = "xyes")
+])
+
+
+dnl Usage:
+dnl   GOBJECT_INTROSPECTION_CHECK([minimum-g-i-version])
+
+AC_DEFUN([GOBJECT_INTROSPECTION_CHECK],
+[
+  _GOBJECT_INTROSPECTION_CHECK_INTERNAL([$1])
+])
+
+dnl Usage:
+dnl   GOBJECT_INTROSPECTION_REQUIRE([minimum-g-i-version])
+
+
+AC_DEFUN([GOBJECT_INTROSPECTION_REQUIRE],
+[
+  _GOBJECT_INTROSPECTION_CHECK_INTERNAL([$1], [require])
+])
diff --git a/configure.ac b/configure.ac
index 5cedb4e..87aa0ad 100644
--- a/configure.ac
+++ b/configure.ac
@@ -99,7 +99,7 @@ AC_CHECK_LIB(expat,XML_ParserCreate,[EXPAT_LIBS="-lexpat"],
 	     [AC_MSG_ERROR([Can't find expat library. Please install expat.])])
 AC_SUBST(EXPAT_LIBS)
 
-AC_CHECK_FUNCS(clearenv fdatasync)
+AC_CHECK_FUNCS(clearenv fdatasync setnetgrent)
 
 if test "x$GCC" = "xyes"; then
   LDFLAGS="-Wl,--as-needed $LDFLAGS"
diff --git a/src/polkit/polkitidentity.c b/src/polkit/polkitidentity.c
index 3aa1f7f..10e9c17 100644
--- a/src/polkit/polkitidentity.c
+++ b/src/polkit/polkitidentity.c
@@ -182,7 +182,15 @@ polkit_identity_from_string  (const gchar   *str,
     }
   else if (g_str_has_prefix (str, "unix-netgroup:"))
     {
+#ifndef HAVE_SETNETGRENT
+      g_set_error (error,
+                   POLKIT_ERROR,
+                   POLKIT_ERROR_FAILED,
+                   "Netgroups are not available on this machine ('%s')",
+                   str);
+#else
       identity = polkit_unix_netgroup_new (str + sizeof "unix-netgroup:" - 1);
+#endif
     }
 
   if (identity == NULL && (error != NULL && *error == NULL))
@@ -344,6 +352,13 @@ polkit_identity_new_for_gvariant (GVariant  *variant,
       GVariant *v;
       const char *name;
 
+#ifndef HAVE_SETNETGRENT
+      g_set_error (error,
+                   POLKIT_ERROR,
+                   POLKIT_ERROR_FAILED,
+                   "Netgroups are not available on this machine");
+      goto out;
+#else
       v = lookup_asv (details_gvariant, "name", G_VARIANT_TYPE_STRING, error);
       if (v == NULL)
         {
@@ -353,6 +368,7 @@ polkit_identity_new_for_gvariant (GVariant  *variant,
       name = g_variant_get_string (v, NULL);
       ret = polkit_unix_netgroup_new (name);
       g_variant_unref (v);
+#endif
     }
   else
     {
diff --git a/src/polkit/polkitunixnetgroup.c b/src/polkit/polkitunixnetgroup.c
index 8a2b369..83f8d4a 100644
--- a/src/polkit/polkitunixnetgroup.c
+++ b/src/polkit/polkitunixnetgroup.c
@@ -194,6 +194,9 @@ polkit_unix_netgroup_set_name (PolkitUnixNetgroup *group,
 PolkitIdentity *
 polkit_unix_netgroup_new (const gchar *name)
 {
+#ifndef HAVE_SETNETGRENT
+  g_assert_not_reached();
+#endif
   g_return_val_if_fail (name != NULL, NULL);
   return POLKIT_IDENTITY (g_object_new (POLKIT_TYPE_UNIX_NETGROUP,
                                        "name", name,
diff --git a/src/polkitbackend/polkitbackendinteractiveauthority.c b/src/polkitbackend/polkitbackendinteractiveauthority.c
index 056d9a8..36c2f3d 100644
--- a/src/polkitbackend/polkitbackendinteractiveauthority.c
+++ b/src/polkitbackend/polkitbackendinteractiveauthority.c
@@ -2233,25 +2233,26 @@ get_users_in_net_group (PolkitIdentity                    *group,
   GList *ret;
 
   ret = NULL;
+#ifdef HAVE_SETNETGRENT
   name = polkit_unix_netgroup_get_name (POLKIT_UNIX_NETGROUP (group));
 
-#ifdef HAVE_SETNETGRENT_RETURN
+# ifdef HAVE_SETNETGRENT_RETURN
   if (setnetgrent (name) == 0)
     {
       g_warning ("Error looking up net group with name %s: %s", name, g_strerror (errno));
       goto out;
     }
-#else
+# else
   setnetgrent (name);
-#endif
+# endif /* HAVE_SETNETGRENT_RETURN */
 
   for (;;)
     {
-#if defined(HAVE_NETBSD) || defined(HAVE_OPENBSD)
+# if defined(HAVE_NETBSD) || defined(HAVE_OPENBSD)
       const char *hostname, *username, *domainname;
-#else
+# else
       char *hostname, *username, *domainname;
-#endif
+# endif /* defined(HAVE_NETBSD) || defined(HAVE_OPENBSD) */
       PolkitIdentity *user;
       GError *error = NULL;
 
@@ -2282,6 +2283,7 @@ get_users_in_net_group (PolkitIdentity                    *group,
 
  out:
   endnetgrent ();
+#endif /* HAVE_SETNETGRENT */
   return ret;
 }
 
diff --git a/src/polkitbackend/polkitbackendjsauthority.cpp b/src/polkitbackend/polkitbackendjsauthority.cpp
index 9b752d1..09b2878 100644
--- a/src/polkitbackend/polkitbackendjsauthority.cpp
+++ b/src/polkitbackend/polkitbackendjsauthority.cpp
@@ -1502,6 +1502,7 @@ js_polkit_user_is_in_netgroup (JSContext  *cx,
 
   JS::CallArgs args = JS::CallArgsFromVp (argc, vp);
 
+#ifdef HAVE_SETNETGRENT
   JS::RootedString usrstr (authority->priv->cx);
   usrstr = args[0].toString();
   user = JS_EncodeStringToUTF8 (cx, usrstr);
@@ -1519,6 +1520,7 @@ js_polkit_user_is_in_netgroup (JSContext  *cx,
 
   JS_free (cx, netgroup);
   JS_free (cx, user);
+#endif
 
   ret = true;
 
diff --git a/test/polkit/polkitidentitytest.c b/test/polkit/polkitidentitytest.c
index e91967b..e829aaa 100644
--- a/test/polkit/polkitidentitytest.c
+++ b/test/polkit/polkitidentitytest.c
@@ -19,6 +19,7 @@
  * Author: Nikki VonHollen <vonhollen@google.com>
  */
 
+#include "config.h"
 #include "glib.h"
 #include <polkit/polkit.h>
 #include <polkit/polkitprivate.h>
@@ -145,11 +146,15 @@ struct ComparisonTestData comparison_test_data [] = {
   {"unix-group:root", "unix-group:jane", FALSE},
   {"unix-group:jane", "unix-group:jane", TRUE},
 
+#ifdef HAVE_SETNETGRENT
   {"unix-netgroup:foo", "unix-netgroup:foo", TRUE},
   {"unix-netgroup:foo", "unix-netgroup:bar", FALSE},
+#endif
 
   {"unix-user:root", "unix-group:root", FALSE},
+#ifdef HAVE_SETNETGRENT
   {"unix-user:jane", "unix-netgroup:foo", FALSE},
+#endif
 
   {NULL},
 };
@@ -181,11 +186,13 @@ main (int argc, char *argv[])
   g_test_add_data_func ("/PolkitIdentity/group_string_2", "unix-group:jane", test_string);
   g_test_add_data_func ("/PolkitIdentity/group_string_3", "unix-group:users", test_string);
 
+#ifdef HAVE_SETNETGRENT
   g_test_add_data_func ("/PolkitIdentity/netgroup_string", "unix-netgroup:foo", test_string);
+  g_test_add_data_func ("/PolkitIdentity/netgroup_gvariant", "unix-netgroup:foo", test_gvariant);
+#endif
 
   g_test_add_data_func ("/PolkitIdentity/user_gvariant", "unix-user:root", test_gvariant);
   g_test_add_data_func ("/PolkitIdentity/group_gvariant", "unix-group:root", test_gvariant);
-  g_test_add_data_func ("/PolkitIdentity/netgroup_gvariant", "unix-netgroup:foo", test_gvariant);
 
   add_comparison_tests ();
 
diff --git a/test/polkit/polkitunixnetgrouptest.c b/test/polkit/polkitunixnetgrouptest.c
index 3701ba1..e3352eb 100644
--- a/test/polkit/polkitunixnetgrouptest.c
+++ b/test/polkit/polkitunixnetgrouptest.c
@@ -19,6 +19,7 @@
  * Author: Nikki VonHollen <vonhollen@google.com>
  */
 
+#include "config.h"
 #include "glib.h"
 #include <polkit/polkit.h>
 #include <string.h>
@@ -69,7 +70,9 @@ int
 main (int argc, char *argv[])
 {
   g_test_init (&argc, &argv, NULL);
+#ifdef HAVE_SETNETGRENT
   g_test_add_func ("/PolkitUnixNetgroup/new", test_new);
   g_test_add_func ("/PolkitUnixNetgroup/set_name", test_set_name);
+#endif
   return g_test_run ();
 }
diff --git a/test/polkitbackend/test-polkitbackendjsauthority.c b/test/polkitbackend/test-polkitbackendjsauthority.c
index 71aad23..fdd28f3 100644
--- a/test/polkitbackend/test-polkitbackendjsauthority.c
+++ b/test/polkitbackend/test-polkitbackendjsauthority.c
@@ -137,12 +137,14 @@ test_get_admin_identities (void)
         "unix-group:users"
       }
     },
+#ifdef HAVE_SETNETGRENT
     {
       "net.company.action3",
       {
         "unix-netgroup:foo"
       }
     },
+#endif
   };
   guint n;
 
-- 
2.25.1