util.rfc6724: Remove, unused since introduction of Happy Eyeballs

It was mainly used to determine whether to try IPv6 or IPv4 first,
following the rules for this in the RFC.

Now we always try IPv6 and IPv4 at roughly the same time, thus there no
need to carry these rules.

1 files changed, 0 insertions, 141 deletions

diff --git a/util/rfc6724.lua b/util/rfc6724.lua
deleted file mode 100644
index 33477ed7..00000000
--- a/util/rfc6724.lua
+++ /dev/null
@@ -1,141 +0,0 @@
--- Prosody IM
--- Copyright (C) 2011-2013 Florian Zeitz
---
--- This project is MIT/X11 licensed. Please see the
--- COPYING file in the source package for more information.
---
-
--- This is used to sort destination addresses by preference
--- during S2S connections.
--- We can't hand this off to getaddrinfo, since it blocks
-
-local ip_commonPrefixLength = require"prosody.util.ip".commonPrefixLength
-
-local function commonPrefixLength(ipA, ipB)
-	local len = ip_commonPrefixLength(ipA, ipB);
-	return len < 64 and len or 64;
-end
-
-local function t_sort(t, comp)
-	for i = 1, (#t - 1) do
-		for j = (i + 1), #t do
-			local a, b = t[i], t[j];
-			if not comp(a,b) then
-				t[i], t[j] = b, a;
-			end
-		end
-	end
-end
-
-local function source(dest, candidates)
-	local function comp(ipA, ipB)
-		-- Rule 1: Prefer same address
-		if dest == ipA then
-			return true;
-		elseif dest == ipB then
-			return false;
-		end
-
-		-- Rule 2: Prefer appropriate scope
-		if ipA.scope < ipB.scope then
-			if ipA.scope < dest.scope then
-				return false;
-			else
-				return true;
-			end
-		elseif ipA.scope > ipB.scope then
-			if ipB.scope < dest.scope then
-				return true;
-			else
-				return false;
-			end
-		end
-
-		-- Rule 3: Avoid deprecated addresses
-		-- XXX: No way to determine this
-		-- Rule 4: Prefer home addresses
-		-- XXX: Mobility Address related, no way to determine this
-		-- Rule 5: Prefer outgoing interface
-		-- XXX: Interface to address relation. No way to determine this
-		-- Rule 6: Prefer matching label
-		if ipA.label == dest.label and ipB.label ~= dest.label then
-			return true;
-		elseif ipB.label == dest.label and ipA.label ~= dest.label then
-			return false;
-		end
-
-		-- Rule 7: Prefer temporary addresses (over public ones)
-		-- XXX: No way to determine this
-		-- Rule 8: Use longest matching prefix
-		if commonPrefixLength(ipA, dest) > commonPrefixLength(ipB, dest) then
-			return true;
-		else
-			return false;
-		end
-	end
-
-	t_sort(candidates, comp);
-	return candidates[1];
-end
-
-local function destination(candidates, sources)
-	local sourceAddrs = {};
-	local function comp(ipA, ipB)
-		local ipAsource = sourceAddrs[ipA];
-		local ipBsource = sourceAddrs[ipB];
-		-- Rule 1: Avoid unusable destinations
-		-- XXX: No such information
-		-- Rule 2: Prefer matching scope
-		if ipA.scope == ipAsource.scope and ipB.scope ~= ipBsource.scope then
-			return true;
-		elseif ipA.scope ~= ipAsource.scope and ipB.scope == ipBsource.scope then
-			return false;
-		end
-
-		-- Rule 3: Avoid deprecated addresses
-		-- XXX: No way to determine this
-		-- Rule 4: Prefer home addresses
-		-- XXX: Mobility Address related, no way to determine this
-		-- Rule 5: Prefer matching label
-		if ipAsource.label == ipA.label and ipBsource.label ~= ipB.label then
-			return true;
-		elseif ipBsource.label == ipB.label and ipAsource.label ~= ipA.label then
-			return false;
-		end
-
-		-- Rule 6: Prefer higher precedence
-		if ipA.precedence > ipB.precedence then
-			return true;
-		elseif ipA.precedence < ipB.precedence then
-			return false;
-		end
-
-		-- Rule 7: Prefer native transport
-		-- XXX: No way to determine this
-		-- Rule 8: Prefer smaller scope
-		if ipA.scope < ipB.scope then
-			return true;
-		elseif ipA.scope > ipB.scope then
-			return false;
-		end
-
-		-- Rule 9: Use longest matching prefix
-		if commonPrefixLength(ipA, ipAsource) > commonPrefixLength(ipB, ipBsource) then
-			return true;
-		elseif commonPrefixLength(ipA, ipAsource) < commonPrefixLength(ipB, ipBsource) then
-			return false;
-		end
-
-		-- Rule 10: Otherwise, leave order unchanged
-		return true;
-	end
-	for _, ip in ipairs(candidates) do
-		sourceAddrs[ip] = source(ip, sources);
-	end
-
-	t_sort(candidates, comp);
-	return candidates;
-end
-
-return {source = source,
-	destination = destination};