From 5cf1a5fe6f8a24f1c95a749e3f347eeed2f591dd Mon Sep 17 00:00:00 2001
From: "A. Wilcox" <AWilcox@Wilcox-Tech.com>
Date: Sun, 15 May 2022 05:04:10 +0000
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.

(sam: rebased for Meson and Duktape.)

Closes: https://gitlab.freedesktop.org/polkit/polkit/-/issues/14
Closes: https://gitlab.freedesktop.org/polkit/polkit/-/issues/163
Closes: https://gitlab.freedesktop.org/polkit/polkit/-/merge_requests/52
Signed-off-by: A. Wilcox <AWilcox@Wilcox-Tech.com>

Ported back the change in configure.ac (upstream removed autotools
support).

Upstream-Status: Backport [https://gitlab.freedesktop.org/polkit/polkit/-/commit/b57deee8178190a7ecc75290fa13cf7daabc2c66]
Signed-off-by: Marta Rybczynska <marta.rybczynska@huawei.com>

---
 configure.ac                                    |  2 +-
 meson.build                                     |  1 +
 src/polkit/polkitidentity.c                     | 17 +++++++++++++++++
 src/polkit/polkitunixnetgroup.c                 |  3 +++
 .../polkitbackendinteractiveauthority.c         | 14 ++++++++------
 src/polkitbackend/polkitbackendjsauthority.cpp  |  2 ++
 test/polkit/polkitidentitytest.c                |  8 +++++++-
 test/polkit/polkitunixnetgrouptest.c            |  2 ++
 .../test-polkitbackendjsauthority.c             |  2 ++
 9 files changed, 43 insertions(+), 8 deletions(-)

diff --git a/configure.ac b/configure.ac
index 18e4223..0f87ea0 100644
--- a/configure.ac
+++ b/configure.ac
@@ -117,7 +117,7 @@ CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
 CC="$PTHREAD_CC"
 AC_CHECK_FUNCS([pthread_condattr_setclock])
 
-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/meson.build b/meson.build
index 7506231..2d9d67a 100644
--- a/meson.build
+++ b/meson.build
@@ -82,6 +82,7 @@ config_h.set('_GNU_SOURCE', true)
 check_functions = [
   'clearenv',
   'fdatasync',
+  'setnetgrent',
 ]
 
 foreach func: check_functions
diff --git a/src/polkit/polkitidentity.c b/src/polkit/polkitidentity.c
index 3aa1f7f..793f17d 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 +352,14 @@ 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 +369,7 @@ 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 11e91c0..9ee0391 100644
--- a/src/polkitbackend/polkitbackendjsauthority.cpp
+++ b/src/polkitbackend/polkitbackendjsauthority.cpp
@@ -1291,6 +1291,7 @@ 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);
@@ -1305,6 +1306,7 @@ js_polkit_user_is_in_netgroup (JSContext  *cx,
     {
       is_in_netgroup =  true;
     }
+#endif
 
   ret = true;
 
diff --git a/test/polkit/polkitidentitytest.c b/test/polkit/polkitidentitytest.c
index e91967b..2635c4c 100644
--- a/test/polkit/polkitidentitytest.c
+++ b/test/polkit/polkitidentitytest.c
@@ -145,11 +145,15 @@ 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 +185,13 @@ 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..e1d211e 100644
--- a/test/polkit/polkitunixnetgrouptest.c
+++ b/test/polkit/polkitunixnetgrouptest.c
@@ -69,7 +69,9 @@ 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 2103b17..b187a2f 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;
 
