1 files changed, 75 insertions, 0 deletions
diff --git a/nss_mapname.c b/nss_mapname.c
new file mode 100644
index 0000000..ea9b7f2
--- /dev/null
+++ b/nss_mapname.c
@@ -0,0 +1,75 @@
+/*
+ * Copyright (C) 2017 Cumulus Networks, Inc.
+ * All rights reserved.
+ * Author: Dave Olson <olson@cumulusnetworks.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program - see the file COPYING.
+ */
+
+/*
+ * This plugin implements getpwnam_r for NSS to map any user
+ * name to a fixed account (from the configuration file).  The
+ * fixed account is used to get the base of the home directory,
+ * and for the uid and gid.  All other fields are replaced, and
+ * the password is always returned as 'x' (disabled).  The assumption
+ * is that any authentication and authorization will be done via PAM
+ * using some mechanism other than the local password file.
+ *
+ * Because it will match any account, this should always be the
+ * last module in /etc/nsswitch.conf for the passwd entry
+ *
+ * The home dir returned is the mapped user homedir with the last component
+ * replaced with the username being looked up.
+ *
+ * See nss_mapuid.c for the matching getpwuid_r for UIDs.
+ */
+
+
+#include "map_common.h"
+
+
+static const char *nssname = "nss_mapuser"; /* for syslogs */
+
+/*
+ * This is an NSS entry point.
+ * We map any username given to the account listed in the configuration file
+ * We only fail if we can't read the configuration file, or the username
+ * in the configuration file can't be found in the /etc/passwd file.
+ * Because we always have a positive reply, it's important that this
+ * be the last NSS module for passwd lookups.
+ */
+__attribute__ ((visibility ("default")))
+enum nss_status _nss_mapname_getpwnam_r(const char *name, struct passwd *pw,
+    char *buffer, size_t buflen, int *errnop)
+{
+    enum nss_status status = NSS_STATUS_NOTFOUND;
+    struct pwbuf pbuf;
+
+    if (nss_mapuser_config(errnop, nssname) == 1) {
+         syslog(LOG_NOTICE, "%s: bad configuration", nssname);
+         return status;
+    }
+
+    /* marshal the args for the lower level functions */
+    pbuf.name = (char *)name;
+    pbuf.pw = pw;
+    pbuf.buf = buffer;
+    pbuf.buflen = buflen;
+    pbuf.errnop = errnop;
+
+    if(!get_pw_mapuser(name, &pbuf))
+        status = NSS_STATUS_SUCCESS;
+
+    return status;
+}