From 0c1debb380fee7f5b2bc62406e45856dc9c9e1a1 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.

Closes polkit/polkit#14.
Signed-off-by: A. Wilcox <AWilcox@Wilcox-Tech.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>

---
 configure.ac                                     |  2 +-
 src/polkit/polkitidentity.c                      | 16 ++++++++++++++++
 src/polkit/polkitunixnetgroup.c                  |  3 +++
 .../polkitbackendinteractiveauthority.c          | 14 ++++++++------
 src/polkitbackend/polkitbackendjsauthority.cpp   |  3 +++
 test/polkit/polkitidentitytest.c                 |  9 ++++++++-
 test/polkit/polkitunixnetgrouptest.c             |  3 +++
 .../test-polkitbackendjsauthority.c              |  2 ++
 8 files changed, 44 insertions(+), 8 deletions(-)

diff --git a/configure.ac b/configure.ac
index b625743..d807086 100644
--- a/configure.ac
+++ b/configure.ac
@@ -100,7 +100,7 @@ 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 ca17108..41d8d5c 100644
--- a/src/polkitbackend/polkitbackendjsauthority.cpp
+++ b/src/polkitbackend/polkitbackendjsauthority.cpp
@@ -1520,6 +1520,7 @@ 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);
@@ -1535,6 +1536,8 @@ js_polkit_user_is_in_netgroup (JSContext  *cx,
       is_in_netgroup =  true;
     }
 
+#endif
+
   ret = true;
 
   args.rval ().setBoolean (is_in_netgroup);
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 f97e0e0..fc52149 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;