+/*
+ * Check if @ai's hostname or aliases fall in a given netgroup.
+ * Return 1 if @ai represents a host in the netgroup, otherwise
+ * zero.
+ */
+#ifdef HAVE_INNETGR
+static int
+check_netgroup(const nfs_client *clp, const struct addrinfo *ai)
+{
+ const char *netgroup = clp->m_hostname + 1;
+ struct addrinfo *tmp = NULL;
+ struct hostent *hp;
+ char *dot, *hname;
+ int i, match;
+
+ match = 0;
+
+ hname = strdup(ai->ai_canonname);
+ if (hname == NULL) {
+ xlog(D_GENERAL, "%s: no memory for strdup", __func__);
+ goto out;
+ }
+
+ /* First, try to match the hostname without
+ * splitting off the domain */
+ if (innetgr(netgroup, hname, NULL, NULL)) {
+ match = 1;
+ goto out;
+ }
+
+ /* See if hname aliases listed in /etc/hosts or nis[+]
+ * match the requested netgroup */
+ hp = gethostbyname(hname);
+ if (hp != NULL) {
+ for (i = 0; hp->h_aliases[i]; i++)
+ if (innetgr(netgroup, hp->h_aliases[i], NULL, NULL)) {
+ match = 1;
+ goto out;
+ }
+ }
+
+ /* If hname happens to be an IP address, convert it
+ * to a the canonical DNS name bound to this address. */
+ tmp = host_pton(hname);
+ if (tmp != NULL) {
+ char *cname = host_canonname(tmp->ai_addr);
+ freeaddrinfo(tmp);
+
+ /* The resulting FQDN may be in our netgroup. */
+ if (cname != NULL) {
+ free(hname);
+ hname = cname;
+ if (innetgr(netgroup, hname, NULL, NULL)) {
+ match = 1;
+ goto out;
+ }
+ }
+ }
+
+ /* Okay, strip off the domain (if we have one) */
+ dot = strchr(hname, '.');
+ if (dot == NULL)
+ goto out;
+
+ *dot = '\0';
+ match = innetgr(netgroup, hname, NULL, NULL);
+
+out:
+ free(hname);
+ return match;
+}
+#else /* !HAVE_INNETGR */