haproxy: use correct ip version on client supplied address

When a user supplies an IP address to use for the HAPROXY protocol,
the IP version reported must be deduced from the address and has
no relation to the IP version used for the upstream connection.

Add test3220 to verify.

Fixes #21340
Reported-by: Fiona Klute
Closes #21341

tests/data/test3220

@@ -0,0 +1,61 @@
+<?xml version="1.0" encoding="US-ASCII"?>
+<testcase>
+<info>
+<keywords>
+HTTP
+HTTP GET
+proxy
+haproxy
+</keywords>
+</info>
+
+# Server-side
+<reply name="%TESTNUMBER">
+<data nocheck="yes">
+HTTP/1.1 200 OK
+Date: Tue, 09 Nov 2010 14:49:00 GMT
+Server: test-server/fake
+Last-Modified: Tue, 13 Jun 2000 12:10:00 GMT
+ETag: "21025-dc7-39462498"
+Accept-Ranges: bytes
+Content-Length: 6
+Connection: close
+Content-Type: text/html
+Funny-head: barkbark
+
+-foo-
+</data>
+</reply>
+
+# Client-side
+<client>
+<server>
+http
+</server>
+<name>
+HTTP GET when PROXY Protocol enabled and spoofed client IP
+</name>
+<command>
+http://%HOSTIP:%HTTPPORT/%TESTNUMBER --haproxy-clientip "2a04:4e42::347" -H "Testno: %TESTNUMBER"
+</command>
+<features>
+proxy
+</features>
+</client>
+
+# Verify data after the test has been "shot"
+<verify>
+<strippart>
+s/^PROXY TCP6 2a04:4e42::347 2a04:4e42::347 (\d*) %HTTPPORT/proxy-line/
+</strippart>
+<protocol crlf="yes">
+proxy-line
+GET /%TESTNUMBER HTTP/1.1
+Host: %HOSTIP:%HTTPPORT
+User-Agent: curl/%VERSION
+Accept: */*
+Testno: %TESTNUMBER
+
+</protocol>
+</verify>
+</testcase>