From e6abcccc5445fe3f129dcdf2ba3d4ef624bef036 Mon Sep 17 00:00:00 2001
From: Phil Davis <phil.davis@inf.org>
Date: Fri, 12 Dec 2014 23:01:07 +0545
Subject: [PATCH] Validation of y/n answers in setlanip

At the moment the user can answer "yes" to most of the questions, but then later code only checks if the answer is "y". Thus you can type in "yes" in some places, have it accepted, but actually the negative action is taken. That is weird and will mess up people who try typing a whole string starting with "y".
With this change it makes the user type one of "y", "yes", "n", "no". When they type 1 of those, it is turned into either "y" or "n". Then the existing implementation logic all works as expected.
Hopefully this is the "final" version that fixes the behavior of the (y/n) questions.
I also included the bit at 296-297 which adds the CIDR bit-count range to the prompt, so the user can see exactly what input is valid/expected there.
Redmine issue #4100
---
 etc/rc.initial.setlanip | 64 +++++++++++++++++++++--------------------
 1 file changed, 33 insertions(+), 31 deletions(-)

diff --git a/etc/rc.initial.setlanip b/etc/rc.initial.setlanip
index 430270da1e..01f2676449 100755
--- a/etc/rc.initial.setlanip
+++ b/etc/rc.initial.setlanip
@@ -55,6 +55,27 @@ require_once("filter.inc");
 require_once("shaper.inc");
 require_once("rrd.inc");
 
+function console_prompt_for_yn ($prompt_text) {
+	global $fp;
+
+	$good_answer = false;
+
+	do {
+		echo "\n" . $prompt_text . " (y/n) ";
+		$yn = strtolower(chop(fgets($fp)));
+		if (($yn == "y") || ($yn == "yes")) {
+			$boolean_answer = true;
+			$good_answer = true;
+		}
+		if (($yn == "n") || ($yn == "no")) {
+			$boolean_answer = false;
+			$good_answer = true;
+		}
+	} while (!$good_answer);
+
+	return $boolean_answer;
+}
+
 function console_get_interface_from_ppp($realif) {
 	global $config;
 
@@ -74,7 +95,7 @@ function prompt_for_enable_dhcp_server($version = 4) {
 	global $config, $fp, $interface;
 	if($interface == "wan") {
 		if($config['interfaces']['lan']) 
-			return "n";
+			return false;
 	}
 	/* only allow DHCP server to be enabled when static IP is
 	   configured on this interface */
@@ -83,19 +104,13 @@ function prompt_for_enable_dhcp_server($version = 4) {
 	} else {
 		$is_ipaddr = is_ipaddrv4($config['interfaces'][$interface]['ipaddr']);
 	}
-	if ($is_ipaddr) {
-		$label_DHCP = ($version === 6) ? "DHCP6" : "DHCP";
-		do {
-			$good = false;
-			$upperifname = strtoupper($interface);
-			echo "\n" . sprintf(gettext("Do you want to enable the %s server on %s? [y|n]"),
-			                    $label_DHCP, $upperifname) . "  ";
-			$yn = strtolower(chop(fgets($fp)));
-			if ($yn[0] == "y" or $yn[0] == "n")
-				$good = true;
-		} while (!$good);
+	if (!($is_ipaddr)) {
+		return false;
 	}
-	return $yn;
+
+	$label_DHCP = ($version === 6) ? "DHCP6" : "DHCP";
+	$upperifname = strtoupper($interface);
+	return console_prompt_for_yn (sprintf(gettext("Do you want to enable the %s server on %s?"), $label_DHCP, $upperifname));
 }
 
 function get_interface_config_description($iface) {
@@ -238,10 +253,7 @@ function console_configure_ip_address($version) {
 	$upperifname = strtoupper($interface);
 
 	if($interface == "wan") {
-		echo sprintf(gettext("Configure %s address %s interface via %s?  [y|n]"),
-		             $label_IPvX, $upperifname, $label_DHCP) . "\n> ";
-		$intdhcp = chop(fgets($fp));
-		if(strtolower($intdhcp) == "y" || strtolower($intdhcp) == "yes") {
+		if (console_prompt_for_yn (sprintf(gettext("Configure %s address %s interface via %s?"), $label_IPvX, $upperifname, $label_DHCP))) {
 			$ifppp = console_get_interface_from_ppp(get_real_interface("wan"));
 			if (!empty($ifppp))
 				$ifaceassigned = $ifppp;
@@ -281,8 +293,8 @@ function console_configure_ip_address($version) {
 				}
 				do {
 					$upperifname = strtoupper($interface);
-					echo "\n" . sprintf(gettext("Enter the new %s %s subnet bit count:"),
-							    $upperifname, $label_IPvX) . "\n> ";
+					echo "\n" . sprintf(gettext("Enter the new %s %s subnet bit count (1 to %s):"),
+							    $upperifname, $label_IPvX, $maxbits) . "\n> ";
 					$intbits = chop(fgets($fp));
 					$intbits_ok = is_numeric($intbits) && (($intbits >= 1) && ($intbits <= $maxbits));
 					$restart_dhcpd = true;
@@ -354,9 +366,7 @@ function console_configure_dhcpd($version = 4) {
 	$label_IPvX = ($version === 6) ? "IPv6"    : "IPv4";
 	$dhcpd      = ($version === 6) ? "dhcpdv6" : "dhcpd";
 
-	if($g['services_dhcp_server_enable'])
-		$yn = prompt_for_enable_dhcp_server($version);
-	if ($yn == "y") {
+	if($g['services_dhcp_server_enable'] && prompt_for_enable_dhcp_server($version)) {
 		$subnet_start = ($version === 6) ? gen_subnetv6($intip6, $intbits6) : gen_subnet($intip, $intbits);
 		$subnet_end = ($version === 6) ? gen_subnetv6_max($intip6, $intbits6) : gen_subnet_max($intip, $intbits);
 		do {
@@ -413,15 +423,7 @@ if (console_configure_dhcpd(6) == 0)
 
 if ($config['system']['webgui']['protocol'] == "https") {
 
-	do {
-		$good = false;
-		echo "\n" . gettext("Do you want to revert to HTTP as the webConfigurator protocol? (y/n)") . " ";
-		$yn = strtolower(chop(fgets($fp)));
-		if ($yn[0] == "y" or $yn[0] == "n")
-			$good = true;
-	} while (!$good);
-
-	if ($yn == "y") {
+	if (console_prompt_for_yn (gettext("Do you want to revert to HTTP as the webConfigurator protocol?"))) {
 		$config['system']['webgui']['protocol'] = "http";
 		$restart_webgui = true;
 	}