Mirrors/coredns
1
0
Fork 0
mirror of https://github.com/coredns/coredns.git synced 2025-11-23 20:24:02 -05:00
Code Issues Packages Projects Releases Wiki Activity

Document fallthrough and fix rewrite (#537)

Browse Source 
* Document fallthrough and fix *reverse*

While documenting the fallthrough behavior and testing it I noticed
the did not properly work. This PR does a tiny bit too much as it

- Documents fallthrough
- Fixes fallthrough in reverse
- Makes directives_generate complain on duplicate priorities
- Moved reverse *before* file in middleware.cfg
- Add a test that tests the reverse fallthrough behavior with a file
  backend

Fixes #515

* ....and fix the tests
This commit is contained in:
Miek Gieben
2017-02-20 21:00:00 +00:00
committed by GitHub
parent 3e26398e08
commit 26242cef1b
9 changed files with 215 additions and 57 deletions
Download Patch File Download Diff File Expand all files Collapse all files

1
middleware/reverse/network.go
View File

@@ -13,7 +13,6 @@ type network struct {
Template string
TTL uint32
RegexMatchIP *regexp.Regexp
Fallthrough bool
}
// TODO: we might want to get rid of these regexes.

28
middleware/reverse/reverse.go
View File

@@ -13,16 +13,14 @@ import (
// Reverse provides dynamic reverse DNS and the related forward RR.
type Reverse struct {
Next middleware.Handler
Networks networks
Next middleware.Handler
Networks networks
Fallthrough bool
}
// ServeDNS implements the middleware.Handler interface.
func (re Reverse) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (int, error) {
var (
rr dns.RR
fallThrough bool
)
var rr dns.RR
state := request.Request{W: w, Req: r}
m := new(dns.Msg)
@@ -42,7 +40,6 @@ func (re Reverse) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg
// loop through the configured networks
for _, n := range re.Networks {
if n.IPnet.Contains(ip) {
fallThrough = n.Fallthrough
rr = &dns.PTR{
Hdr: dns.RR_Header{Name: state.QName(), Rrtype: dns.TypePTR, Class: dns.ClassINET, Ttl: n.TTL},
Ptr: n.ipToHostname(ip),
@@ -54,7 +51,6 @@ func (re Reverse) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg
case dns.TypeA:
for _, n := range re.Networks {
if dns.IsSubDomain(n.Zone, state.Name()) {
fallThrough = n.Fallthrough
// skip if requesting an v4 address and network is not v4
if n.IPnet.IP.To4() == nil {
@@ -75,7 +71,6 @@ func (re Reverse) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg
case dns.TypeAAAA:
for _, n := range re.Networks {
if dns.IsSubDomain(n.Zone, state.Name()) {
fallThrough = n.Fallthrough
// Do not use To16 which tries to make v4 in v6
if n.IPnet.IP.To4() != nil {
@@ -95,14 +90,17 @@ func (re Reverse) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg
}
if rr == nil && !fallThrough {
return middleware.NextOrFailure(re.Name(), re.Next, ctx, w, r)
if rr != nil {
m.Answer = append(m.Answer, rr)
state.SizeAndDo(m)
w.WriteMsg(m)
return dns.RcodeSuccess, nil
}
m.Answer = append(m.Answer, rr)
state.SizeAndDo(m)
w.WriteMsg(m)
return dns.RcodeSuccess, nil
if re.Fallthrough {
return middleware.NextOrFailure(re.Name(), re.Next, ctx, w, r)
}
return dns.RcodeServerFailure, nil
}
// Name implements the Handler interface.

34
middleware/reverse/setup.go
View File

@@ -21,29 +21,29 @@ func init() {
}
func setupReverse(c *caddy.Controller) error {
networks, err := reverseParse(c)
networks, fallThrough, err := reverseParse(c)
if err != nil {
return middleware.Error("reverse", err)
}
dnsserver.GetConfig(c).AddMiddleware(func(next middleware.Handler) middleware.Handler {
return Reverse{Next: next, Networks: networks}
return Reverse{Next: next, Networks: networks, Fallthrough: fallThrough}
})
return nil
}
func reverseParse(c *caddy.Controller) (networks, error) {
var err error
func reverseParse(c *caddy.Controller) (nets networks, fall bool, err error) {
// normalize zones, validation is almost done by dnsserver
// TODO(miek): need sane helpers for these.
zones := make([]string, len(c.ServerBlockKeys))
for i, str := range c.ServerBlockKeys {
host, _, _ := net.SplitHostPort(str)
zones[i] = strings.ToLower(host)
}
networks := networks{}
for c.Next() {
if c.Val() == "reverse" {
@@ -56,42 +56,41 @@ func reverseParse(c *caddy.Controller) (networks, error) {
}
_, ipnet, err := net.ParseCIDR(cidr)
if err != nil {
return nil, c.Errf("network needs to be CIDR formatted: %q\n", cidr)
return nil, false, c.Errf("network needs to be CIDR formatted: %q\n", cidr)
}
cidrs = append(cidrs, ipnet)
}
if len(cidrs) == 0 {
return nil, c.ArgErr()
return nil, false, c.ArgErr()
}
// set defaults
var (
template = "ip-" + templateNameIP + ".{zone[1]}"
ttl = 60
fall = false
)
for c.NextBlock() {
switch c.Val() {
case "hostname":
if !c.NextArg() {
return nil, c.ArgErr()
return nil, false, c.ArgErr()
}
template = c.Val()
case "ttl":
if !c.NextArg() {
return nil, c.ArgErr()
return nil, false, c.ArgErr()
}
ttl, err = strconv.Atoi(c.Val())
if err != nil {
return nil, err
return nil, false, err
}
case "fallthrough":
fall = true
default:
return nil, c.ArgErr()
return nil, false, c.ArgErr()
}
}
@@ -109,7 +108,7 @@ func reverseParse(c *caddy.Controller) (networks, error) {
// extract zone from template
templateZone := strings.SplitAfterN(template, ".", 2)
if len(templateZone) != 2 || templateZone[1] == "" {
return nil, c.Errf("cannot find domain in template '%v'", template)
return nil, false, c.Errf("cannot find domain in template '%v'", template)
}
// Create for each configured network in this stanza
@@ -126,22 +125,21 @@ func reverseParse(c *caddy.Controller) (networks, error) {
regexIP,
1) + "$")
if err != nil {
return nil, err
return nil, false, err
}
networks = append(networks, network{
nets = append(nets, network{
IPnet: ipnet,
Zone: templateZone[1],
Template: template,
RegexMatchIP: regex,
TTL: uint32(ttl),
Fallthrough: fall,
})
}
}
}
// sort by cidr
sort.Sort(networks)
return networks, nil
sort.Sort(nets)
return nets, fall, nil
}

19
middleware/reverse/setup_test.go
View File

@@ -36,7 +36,6 @@ func TestSetupParse(t *testing.T) {
Zone: "domain.com.",
TTL: 60,
RegexMatchIP: regexIP6,
Fallthrough: false,
}},
},
{
@@ -112,14 +111,12 @@ func TestSetupParse(t *testing.T) {
Zone: "dynamic.domain.com.",
TTL: 50,
RegexMatchIP: regexIpv6dynamic,
Fallthrough: false,
}, network{
IPnet: net4,
Template: "dynamic-{ip}-vpn.dynamic.domain.com.",
Zone: "dynamic.domain.com.",
TTL: 60,
RegexMatchIP: regexIpv4vpndynamic,
Fallthrough: true,
}},
},
{
@@ -136,14 +133,12 @@ func TestSetupParse(t *testing.T) {
Zone: "dynamic.domain.com.",
TTL: 50,
RegexMatchIP: regexIpv6dynamic,
Fallthrough: true,
}, network{
IPnet: net4,
Template: "dynamic-{ip}-intern.dynamic.domain.com.",
Zone: "dynamic.domain.com.",
TTL: 50,
RegexMatchIP: regexIpv4dynamic,
Fallthrough: true,
}},
},
{
@@ -160,25 +155,23 @@ func TestSetupParse(t *testing.T) {
Zone: "dynamic.domain.com.",
TTL: 300,
RegexMatchIP: regexIpv6dynamic,
Fallthrough: true,
}},
},
}
for i, test := range tests {
c := caddy.NewTestController("dns", test.inputFileRules)
c.ServerBlockKeys = serverBlockKeys
networks, err := reverseParse(c)
networks, _, err := reverseParse(c)
if err == nil && test.shouldErr {
t.Fatalf("Test %d expected errors, but got no error", i)
} else if err != nil && !test.shouldErr {
t.Fatalf("Test %d expected no errors, but got '%v'", i, err)
} else {
for j, n := range networks {
reflect.DeepEqual(test.networks[j], n)
if !reflect.DeepEqual(test.networks[j], n) {
t.Fatalf("Test %d/%d expected %v, got %v", i, j, test.networks[j], n)
}
}
for j, n := range networks {
reflect.DeepEqual(test.networks[j], n)
if !reflect.DeepEqual(test.networks[j], n) {
t.Fatalf("Test %d/%d expected %v, got %v", i, j, test.networks[j], n)
}
}
}