REGTESTS: ssl: update of a crt with server deletion

This test verifies that a certificate is in a "Unused" state once every
server which uses it are dynamically removed.
diff --git a/reg-tests/ssl/dynamic_server_ssl.vtc b/reg-tests/ssl/dynamic_server_ssl.vtc
new file mode 100644
index 0000000..84854a3
--- /dev/null
+++ b/reg-tests/ssl/dynamic_server_ssl.vtc
@@ -0,0 +1,112 @@
+#REGTEST_TYPE=bug
+# Test if a certicate can be dynamically updated once a server which used it
+# was removed.
+#
+varnishtest "Delete server via cli and update certificates"
+
+feature ignore_unknown_macro
+
+#REQUIRE_VERSION=2.4
+#REQUIRE_OPTIONS=OPENSSL
+feature cmd "command -v socat"
+
+# static server
+server s1 -repeat 3 {
+	rxreq
+	txresp \
+	  -body "resp from s1"
+} -start
+
+haproxy h1 -conf {
+	global
+		stats socket "${tmpdir}/h1/stats" level admin
+
+	defaults
+		mode http
+		timeout connect "${HAPROXY_TEST_TIMEOUT-5s}"
+		timeout client  "${HAPROXY_TEST_TIMEOUT-5s}"
+		timeout server  "${HAPROXY_TEST_TIMEOUT-5s}"
+
+	frontend fe
+		bind "fd@${feS}"
+		default_backend test
+
+	backend test
+		server s1 "${tmpdir}/ssl.sock" ssl verify none crt "${testdir}/client1.pem"
+		server s2 "${tmpdir}/ssl.sock" ssl verify none crt "${testdir}/client1.pem"
+		server s3 "${tmpdir}/ssl.sock" ssl verify none crt "${testdir}/client1.pem"
+
+
+	listen ssl-lst
+		bind "${tmpdir}/ssl.sock" ssl crt "${testdir}/common.pem"
+		server s1 ${s1_addr}:${s1_port}
+
+} -start
+
+
+haproxy h1 -cli {
+    send "show ssl cert ${testdir}/client1.pem"
+    expect ~ ".*SHA1 FingerPrint: D9C3BAE37EA5A7EDB7B3C9BDD4DCB2FE58A412E4"
+}
+client c1 -connect ${h1_feS_sock} {
+	txreq
+	rxresp
+	expect resp.body == "resp from s1"
+} -run
+
+haproxy h1 -cli {
+    send "show ssl cert ${testdir}/client1.pem"
+    expect ~ ".*SHA1 FingerPrint: D9C3BAE37EA5A7EDB7B3C9BDD4DCB2FE58A412E4"
+}
+
+## delete the  servers
+haproxy h1 -cli {
+	send "disable server test/s1"
+	expect ~ ".*"
+	send "disable server test/s2"
+	expect ~ ".*"
+	send "disable server test/s3"
+	expect ~ ".*"
+
+	# valid command
+	send "experimental-mode on; del server test/s1"
+	expect ~ "Server deleted."
+	send "experimental-mode on; del server test/s2"
+	expect ~ "Server deleted."
+	send "experimental-mode on; del server test/s3"
+	expect ~ "Server deleted."
+}
+
+# Replace certificate with an expired one
+shell {
+    printf "set ssl cert ${testdir}/client1.pem <<\n$(cat ${testdir}/client2_expired.pem)\n\n" | socat "${tmpdir}/h1/stats" -
+    echo "commit ssl cert ${testdir}/client1.pem" | socat "${tmpdir}/h1/stats" -
+}
+
+haproxy h1 -cli {
+    send "show ssl cert ${testdir}/client1.pem"
+    expect ~ ".*SHA1 FingerPrint: C625EB01A0A660294B9D7F44C5CEEE5AFC495BE4"
+}
+
+haproxy h1 -cli {
+	send "show ssl cert ${testdir}/client1.pem"
+	expect ~ ".*Status: Unused"
+}
+
+haproxy h1 -cli {
+	send "experimental-mode on; add server test/s1 ${tmpdir}/ssl.sock ssl verify none crt ${testdir}/client1.pem"
+	expect ~ "New server registered."
+	send "enable server test/s1"
+	expect ~ ".*"
+	send "show ssl cert ${testdir}/client1.pem"
+	expect ~ ".*Status: Used"
+}
+
+
+# check that servers are active
+client c1 -connect ${h1_feS_sock} {
+	txreq
+	rxresp
+	expect resp.body == "resp from s1"
+} -run
+