From 423aafbd29ecfe1c3a4f74000e187c60dcc9c8a2 Mon Sep 17 00:00:00 2001
From: Martin Weinelt <martin@darmstadt.freifunk.net>
Date: Wed, 28 Feb 2018 02:57:12 +0100
Subject: [PATCH] gluon-core: improve channel and add chanlist validation

---
 package/gluon-core/check_site.lua | 14 ++++++++++---
 scripts/check_site.lua            | 33 +++++++++++++++++++++++++++++++
 2 files changed, 44 insertions(+), 3 deletions(-)

diff --git a/package/gluon-core/check_site.lua b/package/gluon-core/check_site.lua
index a18aee43..b1482508 100644
--- a/package/gluon-core/check_site.lua
+++ b/package/gluon-core/check_site.lua
@@ -33,9 +33,17 @@ for _, config in ipairs({'wifi24', 'wifi5'}) do
 	if need_table({config}, nil, false) then
 		need_string(in_site({'regdom'})) -- regdom is only required when wifi24 or wifi5 is configured
 
-		need_number({config, 'channel'})
-		if config == 'wifi5' then
-			need_string_match({config, 'outdoor_chanlist'}, '^[%d%s-]+$', false)
+		if config == "wifi24" then
+			local channels = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14}
+			need_one_of({config, 'channel'}, channels)
+		elseif config == 'wifi5' then
+			local channels = {
+				34, 36, 38, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, 62,
+				64, 96, 100, 102, 104, 106, 108, 110, 112, 114, 116, 118, 
+				120, 122, 124, 126, 128, 132, 134, 136, 138, 140, 142, 144, 
+				149, 151, 153, 155, 157, 159, 161, 165, 169, 173 }
+			need_one_of({config, 'channel'}, channels)
+			need_chanlist({config, 'outdoor_chanlist'}, channels, false)
 		end
 
 		obsolete({config, 'supported_rates'}, '802.11b rates are disabled by default.')
diff --git a/scripts/check_site.lua b/scripts/check_site.lua
index 9d65bb69..507fce83 100644
--- a/scripts/check_site.lua
+++ b/scripts/check_site.lua
@@ -203,6 +203,33 @@ function alternatives(...)
 end
 
 
+local function check_chanlist(channels)
+	local is_valid_channel = check_one_of(channels)
+	return function(chanlist)
+		for group in chanlist:gmatch("%S+") do
+			if group:match("^%d+$") then
+				channel = tonumber(group)
+				if not is_valid_channel(channel) then
+					return false
+				end
+			elseif group:match("^%d+-%d+$") then
+				from, to = group:match("^(%d+)-(%d+)$")
+				from = tonumber(from)
+				to = tonumber(to)
+				if from >= to then
+					return false
+				end
+				if not is_valid_channel(from) or not is_valid_channel(to) then
+					return false
+				end
+			else
+				return false
+			end
+		end
+		return true
+	end
+end
+
 function need(path, check, required, msg)
 	local val = loadvar(path)
 	if required == false and val == nil then
@@ -307,6 +334,12 @@ function need_array_of(path, array, required)
 	return need_array(path, function(e) need_one_of(e, array) end, required)
 end
 
+function need_chanlist(path, channels, required)
+	local valid_chanlist = check_chanlist(channels)
+	return need(path, valid_chanlist, required, 'be a space-separated list of WiFi channels or channel-ranges (separated by a hyphen). ' .. 
+	'Valid channels are: ' .. array_to_string(channels))
+end
+
 function need_domain_name(path)
 	need_string(path)
 	need(path, function(domain_name)