From: Michael Tremer <michael.tremer@ipfire.org>
Date: Thu, 8 Sep 2016 17:09:34 +0000 (+0200)
Subject: DHCP: Do not accept overlapping subnet ranges
X-Git-Tag: 009~285
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=ae02c40e7ba474de4d2b49ed1e30ebff350e835e;p=network.git

DHCP: Do not accept overlapping subnet ranges

Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>
---

diff --git a/src/functions/functions.dhcpd b/src/functions/functions.dhcpd
index fbce2050..0c8f7056 100644
--- a/src/functions/functions.dhcpd
+++ b/src/functions/functions.dhcpd
@@ -761,6 +761,13 @@ dhcpd_subnet_range_new() {
 		return ${EXIT_ERROR}
 	fi
 
+	# Search for any overlaps
+	local overlaps=$(dhcpd_subnet_range_overlaps ${proto} ${subnet} ${range})
+	if isset overlaps; then
+		error "DHCP subnet range ${range} overlaps with ${overlaps}"
+		return ${EXIT_ERROR}
+	fi
+
 	# Write the configuration to file.
 	local file=$(dhcpd_subnet_range_path ${proto} ${subnet} ${range})
 	assert isset file
@@ -851,6 +858,57 @@ dhcpd_subnet_range_exists() {
 	return ${EXIT_FALSE}
 }
 
+dhcpd_subnet_range_overlaps() {
+	assert [ $# -eq 3 ]
+
+	local proto=${1}
+	local subnet=${2}
+	local range=${3}
+
+	local start=${range%-*}
+	local end=${range#*-}
+
+	assert isset start
+	assert isset end
+
+	local settings=$(dhcpd_subnet_range_settings ${proto})
+
+	local r ${settings}
+	for r in $(dhcpd_subnet_range_list ${proto} ${subnet}); do
+		dhcpd_subnet_range_read ${proto} ${subnet} ${r}
+
+		# Check if the new range is a sub-range of any existing range
+
+		# Check if the start address is somewhere in this range
+		if ${proto}_addr_ge ${START} ${start} && ${proto}_addr_le ${START} ${end}; then
+			print "${r}"
+			return ${EXIT_TRUE}
+		fi
+
+		# Check if the end address is somewhere in this range
+		if ${proto}_addr_ge ${END} ${start} && ${proto}_addr_le ${END} ${end}; then
+			print "${r}"
+			return ${EXIT_TRUE}
+		fi
+
+		# Check if any existing range is a sub-range of the new range
+
+		# Check if the start address is somewhere in this range
+		if ${proto}_addr_ge ${start} ${START} && ${proto}_addr_le ${start} ${END}; then
+			print "${r}"
+			return ${EXIT_TRUE}
+		fi
+
+		# Check if the end address is somewhere in this range
+		if ${proto}_addr_ge ${end} ${START} && ${proto}_addr_le ${end} ${END}; then
+			print "${r}"
+			return ${EXIT_TRUE}
+		fi
+	done
+
+	return ${EXIT_FALSE}
+}
+
 dhcpd_subnet_settings() {
 	local proto=${1}
 
diff --git a/src/functions/functions.ipv4 b/src/functions/functions.ipv4
index 87a2fdba..0f1455ca 100644
--- a/src/functions/functions.ipv4
+++ b/src/functions/functions.ipv4
@@ -290,6 +290,18 @@ ipv4_addr_gt() {
 		&& return ${EXIT_TRUE} || return ${EXIT_FALSE}
 }
 
+ipv4_addr_ge() {
+	ipv4_addr_eq $@ || ipv4_addr_gt $@
+}
+
+ipv4_addr_lt() {
+	! ipv4_addr_eq $@ && ! ipv4_addr_gt $@
+}
+
+ipv4_addr_le() {
+	ipv4_addr_eq $@ || ! ipv4_addr_gt $@
+}
+
 ipv4_range() {
 	local range=${1}
 
diff --git a/src/functions/functions.ipv6 b/src/functions/functions.ipv6
index 22991353..f2a5fadd 100644
--- a/src/functions/functions.ipv6
+++ b/src/functions/functions.ipv6
@@ -418,6 +418,18 @@ ipv6_addr_gt() {
 		&& return ${EXIT_TRUE} || return ${EXIT_FALSE}
 }
 
+ipv6_addr_ge() {
+	ipv6_addr_eq $@ || ipv6_addr_gt $@
+}
+
+ipv6_addr_lt() {
+	! ipv6_addr_eq $@ && ! ipv6_addr_gt $@
+}
+
+ipv6_addr_le() {
+	ipv6_addr_eq $@ || ! ipv6_addr_gt $@
+}
+
 ipv6_hash() {
 	local address="${1}"
 	assert isset address