[PATCH 2/3] nfs-utils: Don't do tcp wrapper check when there are no rules

[Steve Dickson <SteveD@redhat.com>]

commit 58b7e3ef82c5d9e008befcce391027c4741d3a56
Author: Steve Dickson <steved@redhat.com>
Date:   Fri Jan 23 09:15:57 2009 -0500

    If there are no rules in either /etc/hosts.deny or
    /etc/hosts.allow there is no need to do the host validation.
    
    Signed-off-by: Steve Dickson <steved@redhat.com>

diff --git a/support/misc/tcpwrapper.c b/support/misc/tcpwrapper.c
index a450ad5..098406c 100644
--- a/support/misc/tcpwrapper.c
+++ b/support/misc/tcpwrapper.c
@@ -34,6 +34,7 @@
 #ifdef HAVE_CONFIG_H
 #include <config.h>
 #endif
+#include <stdio.h>
 #include <tcpwrapper.h>
 #include <unistd.h>
 #include <string.h>
@@ -55,6 +56,8 @@
 #include <rpc/rpcent.h>
 #endif
 
+static int check_files(void);
+static int check_rules(void);
 static void logit(int severity, struct sockaddr_in *addr,
 		  u_long procnum, u_long prognum, char *text);
 static void toggle_verboselog(int sig);
@@ -175,6 +178,9 @@ struct sockaddr_in *addr;
     char **sp;
     char *tmpname;
 
+	xlog(D_CALL, "good_client: %s: doing access check on %s",
+		daemon, inet_ntoa(addr->sin_addr));
+
 	/* First check the address. */
 	if (hosts_ctl(daemon, "", inet_ntoa(addr->sin_addr), "") == DENY)
 		return DENY;
@@ -262,8 +268,50 @@ void    check_startup(void)
     (void) signal(SIGINT, toggle_verboselog);
 }
 
+/*
+ * check_rules - check to see if any entries exist in
+ * either hosts file.
+ */
+int check_rules()
+{
+	FILE *fp;
+	char buf[BUFSIZ];
+
+ 	if ((fp = fopen("/etc/hosts.allow", "r")) == NULL)
+		return 0;
+
+	while (fgets(buf, BUFSIZ, fp) != NULL) {
+		/* Check for commented lines */
+		if (buf[0] == '#')
+			continue;
+		/* Check for blank lines */
+		if (buf[strspn(buf, " \t\r\n")] == 0)
+			continue;
+		/* Not emtpy */
+		fclose(fp);
+		return 1;
+	}
+	fclose(fp);
+
+	if ((fp = fopen("/etc/hosts.deny", "r")) == NULL)
+		return 0;
+
+	while (fgets(buf, BUFSIZ, fp) != NULL) {
+		/* Check for commented lines */
+		if (buf[0] == '#')
+			continue;
+		/* Check for blank lines */
+		if (buf[strspn(buf, " \t\r\n")] == 0)
+			continue;
+		/* Not emtpy */
+		fclose(fp);
+		return 1;
+	}
+	fclose(fp);
+	return 0;
+}
+  
 /* check_files - check to see if either access files have changed */
-
 static int check_files()
 {
 	static time_t allow_mtime, deny_mtime;
@@ -305,6 +353,13 @@ u_long  prog;
 	if (acc && changed == 0)
 		return (acc->access);
 
+	/*
+	 * See if there are any rules to be applied,
+	 * if not, no need to check the address
+	 */
+	if (check_rules() == 0)
+		goto done;
+
 	if (!(from_local(addr) || good_client(daemon, addr))) {
 		log_bad_host(addr, proc, prog);
 		if (acc)
@@ -315,11 +370,12 @@ u_long  prog;
 	}
 	if (verboselog)
 		log_client(addr, proc, prog);
-
+done:
 	if (acc)
 		acc->access = TRUE;
 	else 
 		haccess_add(addr, prog, TRUE);
+
     return (TRUE);
 }