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// Copyright 2015 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build darwin dragonfly freebsd linux netbsd openbsd solaris
package net
import (
"os"
"strings"
"testing"
)
type nssHostTest struct {
host string
localhost string
want hostLookupOrder
}
func nssStr(s string) *nssConf { return parseNSSConf(strings.NewReader(s)) }
// represents a dnsConfig returned by parsing a nonexistent resolv.conf
var defaultResolvConf = &dnsConfig{
servers: defaultNS,
ndots: 1,
timeout: 5,
attempts: 2,
err: os.ErrNotExist,
}
func TestConfHostLookupOrder(t *testing.T) {
tests := []struct {
name string
c *conf
resolver *Resolver
hostTests []nssHostTest
}{
{
name: "force",
c: &conf{
forceCgoLookupHost: true,
nss: nssStr("foo: bar"),
resolv: defaultResolvConf,
},
hostTests: []nssHostTest{
{"foo.local", "myhostname", hostLookupCgo},
{"google.com", "myhostname", hostLookupCgo},
},
},
{
name: "netgo_dns_before_files",
c: &conf{
netGo: true,
nss: nssStr("hosts: dns files"),
resolv: defaultResolvConf,
},
hostTests: []nssHostTest{
{"x.com", "myhostname", hostLookupDNSFiles},
},
},
{
name: "netgo_fallback_on_cgo",
c: &conf{
netGo: true,
nss: nssStr("hosts: dns files something_custom"),
resolv: defaultResolvConf,
},
hostTests: []nssHostTest{
{"x.com", "myhostname", hostLookupFilesDNS},
},
},
{
name: "ubuntu_trusty_avahi",
c: &conf{
nss: nssStr("hosts: files mdns4_minimal [NOTFOUND=return] dns mdns4"),
resolv: defaultResolvConf,
},
hostTests: []nssHostTest{
{"foo.local", "myhostname", hostLookupCgo},
{"foo.local.", "myhostname", hostLookupCgo},
{"foo.LOCAL", "myhostname", hostLookupCgo},
{"foo.LOCAL.", "myhostname", hostLookupCgo},
{"google.com", "myhostname", hostLookupFilesDNS},
},
},
{
name: "freebsdlinux_no_resolv_conf",
c: &conf{
goos: "freebsd",
nss: nssStr("foo: bar"),
resolv: defaultResolvConf,
},
hostTests: []nssHostTest{{"google.com", "myhostname", hostLookupFilesDNS}},
},
// On OpenBSD, no resolv.conf means no DNS.
{
name: "openbsd_no_resolv_conf",
c: &conf{
goos: "openbsd",
resolv: defaultResolvConf,
},
hostTests: []nssHostTest{{"google.com", "myhostname", hostLookupFiles}},
},
{
name: "solaris_no_nsswitch",
c: &conf{
goos: "solaris",
nss: &nssConf{err: os.ErrNotExist},
resolv: defaultResolvConf,
},
hostTests: []nssHostTest{{"google.com", "myhostname", hostLookupCgo}},
},
{
name: "openbsd_lookup_bind_file",
c: &conf{
goos: "openbsd",
resolv: &dnsConfig{lookup: []string{"bind", "file"}},
},
hostTests: []nssHostTest{
{"google.com", "myhostname", hostLookupDNSFiles},
{"foo.local", "myhostname", hostLookupDNSFiles},
},
},
{
name: "openbsd_lookup_file_bind",
c: &conf{
goos: "openbsd",
resolv: &dnsConfig{lookup: []string{"file", "bind"}},
},
hostTests: []nssHostTest{{"google.com", "myhostname", hostLookupFilesDNS}},
},
{
name: "openbsd_lookup_bind",
c: &conf{
goos: "openbsd",
resolv: &dnsConfig{lookup: []string{"bind"}},
},
hostTests: []nssHostTest{{"google.com", "myhostname", hostLookupDNS}},
},
{
name: "openbsd_lookup_file",
c: &conf{
goos: "openbsd",
resolv: &dnsConfig{lookup: []string{"file"}},
},
hostTests: []nssHostTest{{"google.com", "myhostname", hostLookupFiles}},
},
{
name: "openbsd_lookup_yp",
c: &conf{
goos: "openbsd",
resolv: &dnsConfig{lookup: []string{"file", "bind", "yp"}},
},
hostTests: []nssHostTest{{"google.com", "myhostname", hostLookupCgo}},
},
{
name: "openbsd_lookup_two",
c: &conf{
goos: "openbsd",
resolv: &dnsConfig{lookup: []string{"file", "foo"}},
},
hostTests: []nssHostTest{{"google.com", "myhostname", hostLookupCgo}},
},
{
name: "openbsd_lookup_empty",
c: &conf{
goos: "openbsd",
resolv: &dnsConfig{lookup: nil},
},
hostTests: []nssHostTest{{"google.com", "myhostname", hostLookupDNSFiles}},
},
// glibc lacking an nsswitch.conf, per
// https://www.gnu.org/software/libc/manual/html_node/Notes-on-NSS-Configuration-File.html
{
name: "linux_no_nsswitch.conf",
c: &conf{
goos: "linux",
nss: &nssConf{err: os.ErrNotExist},
resolv: defaultResolvConf,
},
hostTests: []nssHostTest{{"google.com", "myhostname", hostLookupDNSFiles}},
},
{
name: "files_mdns_dns",
c: &conf{
nss: nssStr("hosts: files mdns dns"),
resolv: defaultResolvConf,
},
hostTests: []nssHostTest{
{"x.com", "myhostname", hostLookupFilesDNS},
{"x.local", "myhostname", hostLookupCgo},
},
},
{
name: "dns_special_hostnames",
c: &conf{
nss: nssStr("hosts: dns"),
resolv: defaultResolvConf,
},
hostTests: []nssHostTest{
{"x.com", "myhostname", hostLookupDNS},
{"x\\.com", "myhostname", hostLookupCgo}, // punt on weird glibc escape
{"foo.com%en0", "myhostname", hostLookupCgo}, // and IPv6 zones
},
},
{
name: "mdns_allow",
c: &conf{
nss: nssStr("hosts: files mdns dns"),
resolv: defaultResolvConf,
hasMDNSAllow: true,
},
hostTests: []nssHostTest{
{"x.com", "myhostname", hostLookupCgo},
{"x.local", "myhostname", hostLookupCgo},
},
},
{
name: "files_dns",
c: &conf{
nss: nssStr("hosts: files dns"),
resolv: defaultResolvConf,
},
hostTests: []nssHostTest{
{"x.com", "myhostname", hostLookupFilesDNS},
{"x", "myhostname", hostLookupFilesDNS},
{"x.local", "myhostname", hostLookupCgo},
},
},
{
name: "dns_files",
c: &conf{
nss: nssStr("hosts: dns files"),
resolv: defaultResolvConf,
},
hostTests: []nssHostTest{
{"x.com", "myhostname", hostLookupDNSFiles},
{"x", "myhostname", hostLookupDNSFiles},
{"x.local", "myhostname", hostLookupCgo},
},
},
{
name: "something_custom",
c: &conf{
nss: nssStr("hosts: dns files something_custom"),
resolv: defaultResolvConf,
},
hostTests: []nssHostTest{
{"x.com", "myhostname", hostLookupCgo},
},
},
{
name: "myhostname",
c: &conf{
nss: nssStr("hosts: files dns myhostname"),
resolv: defaultResolvConf,
},
hostTests: []nssHostTest{
{"x.com", "myhostname", hostLookupFilesDNS},
{"myhostname", "myhostname", hostLookupCgo},
{"myHostname", "myhostname", hostLookupCgo},
{"myhostname.dot", "myhostname.dot", hostLookupCgo},
{"myHostname.dot", "myhostname.dot", hostLookupCgo},
{"gateway", "myhostname", hostLookupCgo},
{"Gateway", "myhostname", hostLookupCgo},
{"localhost", "myhostname", hostLookupCgo},
{"Localhost", "myhostname", hostLookupCgo},
{"anything.localhost", "myhostname", hostLookupCgo},
{"Anything.localhost", "myhostname", hostLookupCgo},
{"localhost.localdomain", "myhostname", hostLookupCgo},
{"Localhost.Localdomain", "myhostname", hostLookupCgo},
{"anything.localhost.localdomain", "myhostname", hostLookupCgo},
{"Anything.Localhost.Localdomain", "myhostname", hostLookupCgo},
{"somehostname", "myhostname", hostLookupFilesDNS},
{"", "myhostname", hostLookupFilesDNS}, // Issue 13623
},
},
{
name: "ubuntu14.04.02",
c: &conf{
nss: nssStr("hosts: files myhostname mdns4_minimal [NOTFOUND=return] dns mdns4"),
resolv: defaultResolvConf,
},
hostTests: []nssHostTest{
{"x.com", "myhostname", hostLookupFilesDNS},
{"somehostname", "myhostname", hostLookupFilesDNS},
{"myhostname", "myhostname", hostLookupCgo},
},
},
// Debian Squeeze is just "dns,files", but lists all
// the default criteria for dns, but then has a
// non-standard but redundant notfound=return for the
// files.
{
name: "debian_squeeze",
c: &conf{
nss: nssStr("hosts: dns [success=return notfound=continue unavail=continue tryagain=continue] files [notfound=return]"),
resolv: defaultResolvConf,
},
hostTests: []nssHostTest{
{"x.com", "myhostname", hostLookupDNSFiles},
{"somehostname", "myhostname", hostLookupDNSFiles},
},
},
{
name: "resolv.conf-unknown",
c: &conf{
nss: nssStr("foo: bar"),
resolv: &dnsConfig{servers: defaultNS, ndots: 1, timeout: 5, attempts: 2, unknownOpt: true},
},
hostTests: []nssHostTest{{"google.com", "myhostname", hostLookupCgo}},
},
// Android should always use cgo.
{
name: "android",
c: &conf{
goos: "android",
nss: nssStr(""),
resolv: defaultResolvConf,
},
hostTests: []nssHostTest{
{"x.com", "myhostname", hostLookupCgo},
},
},
// Issue 24393: make sure "Resolver.PreferGo = true" acts like netgo.
{
name: "resolver-prefergo",
resolver: &Resolver{PreferGo: true},
c: &conf{
goos: "darwin",
forceCgoLookupHost: true, // always true for darwin
resolv: defaultResolvConf,
nss: nssStr(""),
netCgo: true,
},
hostTests: []nssHostTest{
{"localhost", "myhostname", hostLookupFilesDNS},
},
},
}
origGetHostname := getHostname
defer func() { getHostname = origGetHostname }()
for _, tt := range tests {
for _, ht := range tt.hostTests {
getHostname = func() (string, error) { return ht.localhost, nil }
gotOrder := tt.c.hostLookupOrder(tt.resolver, ht.host)
if gotOrder != ht.want {
t.Errorf("%s: hostLookupOrder(%q) = %v; want %v", tt.name, ht.host, gotOrder, ht.want)
}
}
}
}
func TestSystemConf(t *testing.T) {
systemConf()
}
|
