REGTESTS: log: check that a ring's internal server may target a UNIX socket

This test covers the bug fixed by this commit:

    ce6071c3b BUG/MEDIUM: server: skip log backend addr checks for internal proxies

It declares a ring whose server targets a UNIX socket bound by a
log-forward section, itself relaying to a vtest syslog receiver. It
fails to parse on an affected, unpatched build ("log server address
family not supported for log backend server").

The test pins "chroot /" in its global section: when haproxy runs as
root without an explicit "chroot" directive, its automatic "chroot
auto" feature (641fe4f11) isolates the process into an empty directory
right after startup. That breaks the ring's own UNIX-socket "server"
connect, a runtime, repeatedly-retried client connection, unlike the
log-forward listener's "bind unix@..." which is already open before
the chroot happens. Pinning "chroot /" makes the test behave the same
whether run as root or not.

This must be backported wherever the fix above is backported.

diff --git a/reg-tests/log/ring_unix_log_forward.vtc b/reg-tests/log/ring_unix_log_forward.vtc
new file mode 100644 (file)
index 0000000..f8c23fd
--- /dev/null
+++ b/reg-tests/log/ring_unix_log_forward.vtc
@@ -0,0 +1,83 @@
+varnishtest "ring section's internal server may target a UNIX socket"
+
+# 23e5f18b8 ("MEDIUM: sink: change the sink mode type to PR_MODE_SYSLOG")
+# tagged a sink's forward_px (the internal proxy backing a "ring" section)
+# with PR_MODE_SYSLOG. As an unintended side effect, this made ring's own
+# "server" line subject to _srv_check_proxy_mode()'s log-backend
+# address-family check (added by 64e0b6344 for real "mode log" backends),
+# which rejects AF_UNIX. This broke the common "ring -> UNIX socket ->
+# log-forward" pattern, which worked fine before 23e5f18b8.
+#
+# This test declares a ring whose server targets a UNIX socket bound by a
+# log-forward section, which itself relays to a vtest syslog receiver. It
+# fails to parse on an affected, unpatched build ("log server address
+# family not supported for log backend server").
+
+feature cmd "$HAPROXY_PROGRAM -cc 'version_atleast(3.3-dev2)'"
+feature ignore_unknown_macro
+
+syslog Slg1 -level info {
+    recv
+    expect ~ "GET /client_c1 HTTP/1.1"
+} -start
+
+server s1 {
+    rxreq
+    txresp
+} -start
+
+haproxy h1 -conf {
+    global
+    .if feature(THREAD)
+        thread-groups 1
+    .endif
+    # when run as root without an explicit "chroot" directive, haproxy's
+    # automatic "chroot auto" (see 641fe4f11) isolates the process into
+    # an empty directory right after startup. That breaks the ring's own
+    # UNIX-socket "server" connect (a runtime, repeatedly-retried client
+    # connection), unlike the log-forward listener's "bind unix@..."
+    # which is already open before the chroot happens. Pin "chroot /" so
+    # this test behaves the same whether run as root or not.
+    chroot /
+
+       defaults
+               mode http
+               option httplog
+               timeout connect "${HAPROXY_TEST_TIMEOUT-5s}"
+               timeout client  "${HAPROXY_TEST_TIMEOUT-5s}"
+               timeout server  "${HAPROXY_TEST_TIMEOUT-5s}"
+
+       frontend fe1
+               bind "fd@${fe_1}"
+               log ring@buf1 local0
+               default_backend be
+
+       backend be
+               server app1 ${s1_addr}:${s1_port}
+
+       ring buf1
+               description "ring fed via a UNIX-socket server"
+               format rfc5424
+               maxlen 1200
+               size 32764
+               timeout connect 5s
+               timeout server 10s
+               # note: format/maxlen/size above are required for the ring's
+               # forwarder to actually flush to its server - omitting them
+               # leaves the ring silently unable to forward (unrelated to the
+               # fix under test, just a config-authoring trap)
+               # the whole point of this test: a UNIX socket server on a ring
+               server relay unix@"${tmpdir}/ring_unix_log_forward.sock"
+
+       log-forward relay
+               bind unix@"${tmpdir}/ring_unix_log_forward.sock" mode 660
+               log ${Slg1_addr}:${Slg1_port} local0
+} -start
+
+client c1 -connect ${h1_fe_1_sock} {
+    txreq -url "/client_c1"
+    rxresp
+    expect resp.status == 200
+} -run
+
+syslog Slg1 -wait