From 34cfeb2823b7262b81a42c6fff29146216353552 Mon Sep 17 00:00:00 2001
From: Anders Kaseorg <andersk@mit.edu>
Date: Sat, 26 Jun 2010 17:34:37 -0400
Subject: [PATCH] Add supplementary nonlocal gids to local users in
 MAGIC_NONLOCAL_GROUPNAME

Signed-off-by: Anders Kaseorg <andersk@mit.edu>
---
 README           |  4 +++-
 nonlocal-group.c | 15 +++++++++++++--
 2 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/README b/README
index 47067fb..7125dc1 100644
--- a/README
+++ b/README
@@ -13,7 +13,9 @@ The module also assigns special properties to two local groups, if
 they exist:
 
 • If the local group ‘nss-nonlocal-users’ exists, then nonlocal users
-  will be automatically added to it.
+  will be automatically added to it.  Furthermore, if a local user is
+  added to this group, then that user will inherit any nonlocal
+  supplementary gids from a nonlocal user of the same name.
 
 • If the local group ‘nss-local-users’ exists, then local users will
   be automatically added to it.
diff --git a/nonlocal-group.c b/nonlocal-group.c
index e93a3a2..aa9c588 100644
--- a/nonlocal-group.c
+++ b/nonlocal-group.c
@@ -40,7 +40,9 @@
 
 /*
  * If the MAGIC_NONLOCAL_GROUPNAME local group exists, then nonlocal
- * users will be automatically added to it.
+ * users will be automatically added to it.  Furthermore, if a local
+ * user is added to this group, then that user will inherit any
+ * nonlocal supplementary gids from a nonlocal user of the same name.
  */
 #define MAGIC_NONLOCAL_GROUPNAME "nss-nonlocal-users"
 
@@ -338,7 +340,8 @@ _nss_nonlocal_initgroups_dyn(const char *user, gid_t group, long int *start,
     char *buffer;
     int in, out, i;
 
-    /* Check that the user is a nonlocal user before adding any groups. */
+    /* Check that the user is a nonlocal user, or a member of the
+     * MAGIC_NONLOCAL_GROUPNAME group, before adding any groups. */
     status = check_nonlocal_user(user, errnop);
     if (status == NSS_STATUS_TRYAGAIN) {
 	return status;
@@ -369,6 +372,14 @@ _nss_nonlocal_initgroups_dyn(const char *user, gid_t group, long int *start,
 	    if (!add_group(nonlocal_users_group.gr_gid, start, size, groupsp,
 			   limit, errnop, &status))
 		return status;
+	} else {
+	    int i;
+	    for (i = 0; i < *start; ++i) {
+		if ((*groupsp)[i] == nonlocal_users_group.gr_gid) {
+		    is_nonlocal = true;
+		    break;
+		}
+	    }
 	}
     } else if (status == NSS_STATUS_TRYAGAIN) {
 	if (is_nonlocal)
-- 
2.44.0