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  • ai3/tools/acmeserver
  • godog/acmeserver
  • svp-bot/acmeserver
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with 1398 additions and 1308 deletions
......@@ -7,10 +7,10 @@
> Less is more.
Complete and usable DNS library. All widely used Resource Records are supported, including the
DNSSEC types. It follows a lean and mean philosophy. If there is stuff you should know as a DNS
programmer there isn't a convenience function for it. Server side and client side programming is
supported, i.e. you can build servers and resolvers with it.
Complete and usable DNS library. All Resource Records are supported, including the DNSSEC types.
It follows a lean and mean philosophy. If there is stuff you should know as a DNS programmer there
isn't a convenience function for it. Server side and client side programming is supported, i.e. you
can build servers and resolvers with it.
We try to keep the "master" branch as sane as possible and at the bleeding edge of standards,
avoiding breaking changes wherever reasonable. We support the last two versions of Go.
......@@ -26,8 +26,8 @@ avoiding breaking changes wherever reasonable. We support the last two versions
A not-so-up-to-date-list-that-may-be-actually-current:
* https://github.com/coredns/coredns
* https://cloudflare.com
* https://github.com/abh/geodns
* https://github.com/baidu/bfe
* http://www.statdns.com/
* http://www.dnsinspect.com/
* https://github.com/chuangbo/jianbing-dictionary-dns
......@@ -41,12 +41,9 @@ A not-so-up-to-date-list-that-may-be-actually-current:
* https://github.com/StalkR/dns-reverse-proxy
* https://github.com/tianon/rawdns
* https://mesosphere.github.io/mesos-dns/
* https://pulse.turbobytes.com/
* https://play.google.com/store/apps/details?id=com.turbobytes.dig
* https://github.com/fcambus/statzone
* https://github.com/benschw/dns-clb-go
* https://github.com/corny/dnscheck for http://public-dns.info/
* https://namesmith.io
* https://github.com/corny/dnscheck for <http://public-dns.info/>
* https://github.com/miekg/unbound
* https://github.com/miekg/exdns
* https://dnslookup.org
......@@ -55,54 +52,66 @@ A not-so-up-to-date-list-that-may-be-actually-current:
* https://github.com/mehrdadrad/mylg
* https://github.com/bamarni/dockness
* https://github.com/fffaraz/microdns
* http://kelda.io
* https://github.com/ipdcode/hades (JD.COM)
* https://github.com/ipdcode/hades <https://jd.com>
* https://github.com/StackExchange/dnscontrol/
* https://www.dnsperf.com/
* https://dnssectest.net/
* https://dns.apebits.com
* https://github.com/oif/apex
* https://github.com/jedisct1/dnscrypt-proxy
* https://github.com/jedisct1/rpdns
* https://github.com/xor-gate/sshfp
* https://github.com/rs/dnstrace
* https://blitiri.com.ar/p/dnss ([github mirror](https://github.com/albertito/dnss))
* https://render.com
* https://github.com/peterzen/goresolver
* https://github.com/folbricht/routedns
* https://domainr.com/
* https://zonedb.org/
* https://router7.org/
* https://github.com/fortio/dnsping
* https://github.com/Luzilla/dnsbl_exporter
* https://github.com/bodgit/tsig
* https://github.com/v2fly/v2ray-core (test only)
* https://kuma.io/
* https://www.misaka.io/services/dns
* https://ping.sx/dig
* https://fleetdeck.io/
* https://github.com/markdingo/autoreverse
Send pull request if you want to be listed here.
# Features
* UDP/TCP queries, IPv4 and IPv6;
* RFC 1035 zone file parsing ($INCLUDE, $ORIGIN, $TTL and $GENERATE (for all record types) are supported;
* Fast:
* Reply speed around ~ 80K qps (faster hardware results in more qps);
* Parsing RRs ~ 100K RR/s, that's 5M records in about 50 seconds;
* Server side programming (mimicking the net/http package);
* Client side programming;
* DNSSEC: signing, validating and key generation for DSA, RSA, ECDSA and Ed25519;
* EDNS0, NSID, Cookies;
* AXFR/IXFR;
* TSIG, SIG(0);
* DNS over TLS: optional encrypted connection between client and server;
* DNS name compression;
* Depends only on the standard library.
* UDP/TCP queries, IPv4 and IPv6
* RFC 1035 zone file parsing ($INCLUDE, $ORIGIN, $TTL and $GENERATE (for all record types) are supported
* Fast
* Server side programming (mimicking the net/http package)
* Client side programming
* DNSSEC: signing, validating and key generation for DSA, RSA, ECDSA and Ed25519
* EDNS0, NSID, Cookies
* AXFR/IXFR
* TSIG, SIG(0)
* DNS over TLS (DoT): encrypted connection between client and server over TCP
* DNS name compression
Have fun!
Miek Gieben - 2010-2012 - <miek@miek.nl>
DNS Authors 2012-
# Building
Building is done with the `go` tool. If you have setup your GOPATH correctly, the following should
work:
This library uses Go modules and uses semantic versioning. Building is done with the `go` tool, so
the following should work:
go get github.com/miekg/dns
go build github.com/miekg/dns
## Examples
A short "how to use the API" is at the beginning of doc.go (this also will show
when you call `godoc github.com/miekg/dns`).
A short "how to use the API" is at the beginning of doc.go (this also will show when you call `godoc
github.com/miekg/dns`).
Example programs can be found in the `github.com/miekg/exdns` repository.
......@@ -126,6 +135,7 @@ Example programs can be found in the `github.com/miekg/exdns` repository.
* 2915 - NAPTR record
* 2929 - DNS IANA Considerations
* 3110 - RSASHA1 DNS keys
* 3123 - APL record
* 3225 - DO bit (DNSSEC OK)
* 340{1,2,3} - NAPTR record
* 3445 - Limiting the scope of (DNS)KEY
......@@ -152,6 +162,7 @@ Example programs can be found in the `github.com/miekg/exdns` repository.
* 6844 - CAA record
* 6891 - EDNS0 update
* 6895 - DNS IANA considerations
* 6944 - DNSSEC DNSKEY Algorithm Status
* 6975 - Algorithm Understanding in DNSSEC
* 7043 - EUI48/EUI64 records
* 7314 - DNS (EDNS) EXPIRE Option
......@@ -160,12 +171,16 @@ Example programs can be found in the `github.com/miekg/exdns` repository.
* 7553 - URI record
* 7858 - DNS over TLS: Initiation and Performance Considerations
* 7871 - EDNS0 Client Subnet
* 7873 - Domain Name System (DNS) Cookies (draft-ietf-dnsop-cookies)
* 7873 - Domain Name System (DNS) Cookies
* 8080 - EdDSA for DNSSEC
* 8499 - DNS Terminology
* 8659 - DNS Certification Authority Authorization (CAA) Resource Record
* 8914 - Extended DNS Errors
* 8976 - Message Digest for DNS Zones (ZONEMD RR)
## Loosely based upon
## Loosely Based Upon
* `ldns`
* `NSD`
* `Net::DNS`
* `GRONG`
* ldns - <https://nlnetlabs.nl/projects/ldns/about/>
* NSD - <https://nlnetlabs.nl/projects/nsd/about/>
* Net::DNS - <http://www.net-dns.org/>
* GRONG - <https://github.com/bortzmeyer/grong>
package dns
// MsgAcceptFunc is used early in the server code to accept or reject a message with RcodeFormatError.
// It returns a MsgAcceptAction to indicate what should happen with the message.
type MsgAcceptFunc func(dh Header) MsgAcceptAction
// DefaultMsgAcceptFunc checks the request and will reject if:
//
// * isn't a request (don't respond in that case)
//
// * opcode isn't OpcodeQuery or OpcodeNotify
//
// * Zero bit isn't zero
//
// * does not have exactly 1 question in the question section
//
// * has more than 1 RR in the Answer section
//
// * has more than 0 RRs in the Authority section
//
// * has more than 2 RRs in the Additional section
//
var DefaultMsgAcceptFunc MsgAcceptFunc = defaultMsgAcceptFunc
// MsgAcceptAction represents the action to be taken.
type MsgAcceptAction int
// Allowed returned values from a MsgAcceptFunc.
const (
MsgAccept MsgAcceptAction = iota // Accept the message
MsgReject // Reject the message with a RcodeFormatError
MsgIgnore // Ignore the error and send nothing back.
MsgRejectNotImplemented // Reject the message with a RcodeNotImplemented
)
func defaultMsgAcceptFunc(dh Header) MsgAcceptAction {
if isResponse := dh.Bits&_QR != 0; isResponse {
return MsgIgnore
}
// Don't allow dynamic updates, because then the sections can contain a whole bunch of RRs.
opcode := int(dh.Bits>>11) & 0xF
if opcode != OpcodeQuery && opcode != OpcodeNotify {
return MsgRejectNotImplemented
}
if dh.Qdcount != 1 {
return MsgReject
}
// NOTIFY requests can have a SOA in the ANSWER section. See RFC 1996 Section 3.7 and 3.11.
if dh.Ancount > 1 {
return MsgReject
}
// IXFR request could have one SOA RR in the NS section. See RFC 1995, section 3.
if dh.Nscount > 1 {
return MsgReject
}
if dh.Arcount > 2 {
return MsgReject
}
return MsgAccept
}
......@@ -3,15 +3,12 @@ package dns
// A client implementation.
import (
"bytes"
"context"
"crypto/tls"
"encoding/binary"
"fmt"
"io"
"io/ioutil"
"net"
"net/http"
"strings"
"time"
)
......@@ -19,18 +16,37 @@ import (
const (
dnsTimeout time.Duration = 2 * time.Second
tcpIdleTimeout time.Duration = 8 * time.Second
dohMimeType = "application/dns-message"
)
func isPacketConn(c net.Conn) bool {
if _, ok := c.(net.PacketConn); !ok {
return false
}
if ua, ok := c.LocalAddr().(*net.UnixAddr); ok {
return ua.Net == "unixgram" || ua.Net == "unixpacket"
}
return true
}
// A Conn represents a connection to a DNS server.
type Conn struct {
net.Conn // a net.Conn holding the connection
UDPSize uint16 // minimum receive buffer for UDP messages
TsigSecret map[string]string // secret(s) for Tsig map[<zonename>]<base64 secret>, zonename must be in canonical form (lowercase, fqdn, see RFC 4034 Section 6.2)
TsigProvider TsigProvider // An implementation of the TsigProvider interface. If defined it replaces TsigSecret and is used for all TSIG operations.
tsigRequestMAC string
}
func (co *Conn) tsigProvider() TsigProvider {
if co.TsigProvider != nil {
return co.TsigProvider
}
// tsigSecretProvider will return ErrSecret if co.TsigSecret is nil.
return tsigSecretProvider(co.TsigSecret)
}
// A Client defines parameters for a DNS client.
type Client struct {
Net string // if "tcp" or "tcp-tls" (DNS over TLS) a TCP query will be initiated, otherwise an UDP one (default is "" for UDP)
......@@ -39,13 +55,13 @@ type Client struct {
Dialer *net.Dialer // a net.Dialer used to set local address, timeouts and more
// Timeout is a cumulative timeout for dial, write and read, defaults to 0 (disabled) - overrides DialTimeout, ReadTimeout,
// WriteTimeout when non-zero. Can be overridden with net.Dialer.Timeout (see Client.ExchangeWithDialer and
// Client.Dialer) or context.Context.Deadline (see the deprecated ExchangeContext)
// Client.Dialer) or context.Context.Deadline (see ExchangeContext)
Timeout time.Duration
DialTimeout time.Duration // net.DialTimeout, defaults to 2 seconds, or net.Dialer.Timeout if expiring earlier - overridden by Timeout when that value is non-zero
ReadTimeout time.Duration // net.Conn.SetReadTimeout value for connections, defaults to 2 seconds - overridden by Timeout when that value is non-zero
WriteTimeout time.Duration // net.Conn.SetWriteTimeout value for connections, defaults to 2 seconds - overridden by Timeout when that value is non-zero
HTTPClient *http.Client // The http.Client to use for DNS-over-HTTPS
TsigSecret map[string]string // secret(s) for Tsig map[<zonename>]<base64 secret>, zonename must be in canonical form (lowercase, fqdn, see RFC 4034 Section 6.2)
TsigProvider TsigProvider // An implementation of the TsigProvider interface. If defined it replaces TsigSecret and is used for all TSIG operations.
SingleInflight bool // if true suppress multiple outstanding queries for the same Qname, Qtype and Qclass
group singleflight
}
......@@ -86,42 +102,47 @@ func (c *Client) writeTimeout() time.Duration {
// Dial connects to the address on the named network.
func (c *Client) Dial(address string) (conn *Conn, err error) {
return c.DialContext(context.Background(), address)
}
// DialContext connects to the address on the named network, with a context.Context.
// For TLS over TCP (DoT) the context isn't used yet. This will be enabled when Go 1.18 is released.
func (c *Client) DialContext(ctx context.Context, address string) (conn *Conn, err error) {
// create a new dialer with the appropriate timeout
var d net.Dialer
if c.Dialer == nil {
d = net.Dialer{Timeout: c.getTimeoutForRequest(c.dialTimeout())}
} else {
d = net.Dialer(*c.Dialer)
}
network := "udp"
useTLS := false
switch c.Net {
case "tcp-tls":
network = "tcp"
useTLS = true
case "tcp4-tls":
network = "tcp4"
useTLS = true
case "tcp6-tls":
network = "tcp6"
useTLS = true
default:
if c.Net != "" {
network = c.Net
}
d = *c.Dialer
}
network := c.Net
if network == "" {
network = "udp"
}
useTLS := strings.HasPrefix(network, "tcp") && strings.HasSuffix(network, "-tls")
conn = new(Conn)
if useTLS {
network = strings.TrimSuffix(network, "-tls")
// TODO(miekg): Enable after Go 1.18 is released, to be able to support two prev. releases.
/*
tlsDialer := tls.Dialer{
NetDialer: &d,
Config: c.TLSConfig,
}
conn.Conn, err = tlsDialer.DialContext(ctx, network, address)
*/
conn.Conn, err = tls.DialWithDialer(&d, network, address, c.TLSConfig)
} else {
conn.Conn, err = d.Dial(network, address)
conn.Conn, err = d.DialContext(ctx, network, address)
}
if err != nil {
return nil, err
}
conn.UDPSize = c.UDPSize
return conn, nil
}
......@@ -140,47 +161,55 @@ func (c *Client) Dial(address string) (conn *Conn, err error) {
// To specify a local address or a timeout, the caller has to set the `Client.Dialer`
// attribute appropriately
func (c *Client) Exchange(m *Msg, address string) (r *Msg, rtt time.Duration, err error) {
if !c.SingleInflight {
if c.Net == "https" {
// TODO(tmthrgd): pipe timeouts into exchangeDOH
return c.exchangeDOH(context.TODO(), m, address)
}
co, err := c.Dial(address)
return c.exchange(m, address)
if err != nil {
return nil, 0, err
}
defer co.Close()
return c.ExchangeWithConn(m, co)
}
t := "nop"
if t1, ok := TypeToString[m.Question[0].Qtype]; ok {
t = t1
}
cl := "nop"
if cl1, ok := ClassToString[m.Question[0].Qclass]; ok {
cl = cl1
// ExchangeWithConn has the same behavior as Exchange, just with a predetermined connection
// that will be used instead of creating a new one.
// Usage pattern with a *dns.Client:
//
// c := new(dns.Client)
// // connection management logic goes here
//
// conn := c.Dial(address)
// in, rtt, err := c.ExchangeWithConn(message, conn)
//
// This allows users of the library to implement their own connection management,
// as opposed to Exchange, which will always use new connections and incur the added overhead
// that entails when using "tcp" and especially "tcp-tls" clients.
//
// When the singleflight is set for this client the context is _not_ forwarded to the (shared) exchange, to
// prevent one cancelation from canceling all outstanding requests.
func (c *Client) ExchangeWithConn(m *Msg, conn *Conn) (r *Msg, rtt time.Duration, err error) {
return c.exchangeWithConnContext(context.Background(), m, conn)
}
func (c *Client) exchangeWithConnContext(ctx context.Context, m *Msg, conn *Conn) (r *Msg, rtt time.Duration, err error) {
if !c.SingleInflight {
return c.exchangeContext(ctx, m, conn)
}
r, rtt, err, shared := c.group.Do(m.Question[0].Name+t+cl, func() (*Msg, time.Duration, error) {
if c.Net == "https" {
// TODO(tmthrgd): pipe timeouts into exchangeDOH
return c.exchangeDOH(context.TODO(), m, address)
}
return c.exchange(m, address)
q := m.Question[0]
key := fmt.Sprintf("%s:%d:%d", q.Name, q.Qtype, q.Qclass)
r, rtt, err, shared := c.group.Do(key, func() (*Msg, time.Duration, error) {
// When we're doing singleflight we don't want one context cancelation, cancel _all_ outstanding queries.
// Hence we ignore the context and use Background().
return c.exchangeContext(context.Background(), m, conn)
})
if r != nil && shared {
r = r.Copy()
}
return r, rtt, err
}
func (c *Client) exchange(m *Msg, a string) (r *Msg, rtt time.Duration, err error) {
var co *Conn
co, err = c.Dial(a)
if err != nil {
return nil, 0, err
}
defer co.Close()
func (c *Client) exchangeContext(ctx context.Context, m *Msg, co *Conn) (r *Msg, rtt time.Duration, err error) {
opt := m.IsEdns0()
// If EDNS0 is used use that for size.
if opt != nil && opt.UDPSize() >= MinMsgSize {
......@@ -191,82 +220,44 @@ func (c *Client) exchange(m *Msg, a string) (r *Msg, rtt time.Duration, err erro
co.UDPSize = c.UDPSize
}
co.TsigSecret = c.TsigSecret
t := time.Now()
// write with the appropriate write timeout
co.SetWriteDeadline(t.Add(c.getTimeoutForRequest(c.writeTimeout())))
if err = co.WriteMsg(m); err != nil {
return nil, 0, err
}
co.SetReadDeadline(time.Now().Add(c.getTimeoutForRequest(c.readTimeout())))
r, err = co.ReadMsg()
if err == nil && r.Id != m.Id {
err = ErrId
}
rtt = time.Since(t)
return r, rtt, err
}
func (c *Client) exchangeDOH(ctx context.Context, m *Msg, a string) (r *Msg, rtt time.Duration, err error) {
p, err := m.Pack()
if err != nil {
return nil, 0, err
}
req, err := http.NewRequest(http.MethodPost, a, bytes.NewReader(p))
if err != nil {
return nil, 0, err
}
req.Header.Set("Content-Type", dohMimeType)
req.Header.Set("Accept", dohMimeType)
hc := http.DefaultClient
if c.HTTPClient != nil {
hc = c.HTTPClient
}
if ctx != context.Background() && ctx != context.TODO() {
req = req.WithContext(ctx)
}
t := time.Now()
resp, err := hc.Do(req)
if err != nil {
return nil, 0, err
}
defer closeHTTPBody(resp.Body)
if resp.StatusCode != http.StatusOK {
return nil, 0, fmt.Errorf("dns: server returned HTTP %d error: %q", resp.StatusCode, resp.Status)
writeDeadline := t.Add(c.getTimeoutForRequest(c.writeTimeout()))
readDeadline := t.Add(c.getTimeoutForRequest(c.readTimeout()))
if deadline, ok := ctx.Deadline(); ok {
if deadline.Before(writeDeadline) {
writeDeadline = deadline
}
if deadline.Before(readDeadline) {
readDeadline = deadline
}
}
co.SetWriteDeadline(writeDeadline)
co.SetReadDeadline(readDeadline)
if ct := resp.Header.Get("Content-Type"); ct != dohMimeType {
return nil, 0, fmt.Errorf("dns: unexpected Content-Type %q; expected %q", ct, dohMimeType)
}
co.TsigSecret, co.TsigProvider = c.TsigSecret, c.TsigProvider
p, err = ioutil.ReadAll(resp.Body)
if err != nil {
if err = co.WriteMsg(m); err != nil {
return nil, 0, err
}
rtt = time.Since(t)
r = new(Msg)
if err := r.Unpack(p); err != nil {
return r, 0, err
if isPacketConn(co.Conn) {
for {
r, err = co.ReadMsg()
// Ignore replies with mismatched IDs because they might be
// responses to earlier queries that timed out.
if err != nil || r.Id == m.Id {
break
}
}
} else {
r, err = co.ReadMsg()
if err == nil && r.Id != m.Id {
err = ErrId
}
}
// TODO: TSIG? Is it even supported over DoH?
return r, rtt, nil
}
func closeHTTPBody(r io.ReadCloser) error {
io.Copy(ioutil.Discard, io.LimitReader(r, 8<<20))
return r.Close()
rtt = time.Since(t)
return r, rtt, err
}
// ReadMsg reads a message from the connection co.
......@@ -288,11 +279,8 @@ func (co *Conn) ReadMsg() (*Msg, error) {
return m, err
}
if t := m.IsTsig(); t != nil {
if _, ok := co.TsigSecret[t.Hdr.Name]; !ok {
return m, ErrSecret
}
// Need to work on the original message p, as that was used to calculate the tsig.
err = TsigVerify(p, co.TsigSecret[t.Hdr.Name], co.tsigRequestMAC, false)
err = TsigVerifyWithProvider(p, co.tsigProvider(), co.tsigRequestMAC, false)
}
return m, err
}
......@@ -307,24 +295,21 @@ func (co *Conn) ReadMsgHeader(hdr *Header) ([]byte, error) {
err error
)
switch t := co.Conn.(type) {
case *net.TCPConn, *tls.Conn:
r := t.(io.Reader)
// First two bytes specify the length of the entire message.
l, err := tcpMsgLen(r)
if err != nil {
return nil, err
}
p = make([]byte, l)
n, err = tcpRead(r, p)
default:
if isPacketConn(co.Conn) {
if co.UDPSize > MinMsgSize {
p = make([]byte, co.UDPSize)
} else {
p = make([]byte, MinMsgSize)
}
n, err = co.Read(p)
} else {
var length uint16
if err := binary.Read(co.Conn, binary.BigEndian, &length); err != nil {
return nil, err
}
p = make([]byte, length)
n, err = io.ReadFull(co.Conn, p)
}
if err != nil {
......@@ -344,78 +329,26 @@ func (co *Conn) ReadMsgHeader(hdr *Header) ([]byte, error) {
return p, err
}
// tcpMsgLen is a helper func to read first two bytes of stream as uint16 packet length.
func tcpMsgLen(t io.Reader) (int, error) {
p := []byte{0, 0}
n, err := t.Read(p)
if err != nil {
return 0, err
}
// As seen with my local router/switch, returns 1 byte on the above read,
// resulting a a ShortRead. Just write it out (instead of loop) and read the
// other byte.
if n == 1 {
n1, err := t.Read(p[1:])
if err != nil {
return 0, err
}
n += n1
}
if n != 2 {
return 0, ErrShortRead
}
l := binary.BigEndian.Uint16(p)
if l == 0 {
return 0, ErrShortRead
}
return int(l), nil
}
// tcpRead calls TCPConn.Read enough times to fill allocated buffer.
func tcpRead(t io.Reader, p []byte) (int, error) {
n, err := t.Read(p)
if err != nil {
return n, err
}
for n < len(p) {
j, err := t.Read(p[n:])
if err != nil {
return n, err
}
n += j
}
return n, err
}
// Read implements the net.Conn read method.
func (co *Conn) Read(p []byte) (n int, err error) {
if co.Conn == nil {
return 0, ErrConnEmpty
}
if len(p) < 2 {
return 0, io.ErrShortBuffer
if isPacketConn(co.Conn) {
// UDP connection
return co.Conn.Read(p)
}
switch t := co.Conn.(type) {
case *net.TCPConn, *tls.Conn:
r := t.(io.Reader)
l, err := tcpMsgLen(r)
if err != nil {
return 0, err
}
if l > len(p) {
return int(l), io.ErrShortBuffer
}
return tcpRead(r, p[:l])
var length uint16
if err := binary.Read(co.Conn, binary.BigEndian, &length); err != nil {
return 0, err
}
// UDP connection
n, err = co.Conn.Read(p)
if err != nil {
return n, err
if int(length) > len(p) {
return 0, io.ErrShortBuffer
}
return n, err
return io.ReadFull(co.Conn, p[:length])
}
// WriteMsg sends a message through the connection co.
......@@ -424,46 +357,32 @@ func (co *Conn) Read(p []byte) (n int, err error) {
func (co *Conn) WriteMsg(m *Msg) (err error) {
var out []byte
if t := m.IsTsig(); t != nil {
mac := ""
if _, ok := co.TsigSecret[t.Hdr.Name]; !ok {
return ErrSecret
}
out, mac, err = TsigGenerate(m, co.TsigSecret[t.Hdr.Name], co.tsigRequestMAC, false)
// Set for the next read, although only used in zone transfers
co.tsigRequestMAC = mac
// Set tsigRequestMAC for the next read, although only used in zone transfers.
out, co.tsigRequestMAC, err = TsigGenerateWithProvider(m, co.tsigProvider(), co.tsigRequestMAC, false)
} else {
out, err = m.Pack()
}
if err != nil {
return err
}
if _, err = co.Write(out); err != nil {
return err
}
return nil
_, err = co.Write(out)
return err
}
// Write implements the net.Conn Write method.
func (co *Conn) Write(p []byte) (n int, err error) {
switch t := co.Conn.(type) {
case *net.TCPConn, *tls.Conn:
w := t.(io.Writer)
lp := len(p)
if lp < 2 {
return 0, io.ErrShortBuffer
}
if lp > MaxMsgSize {
return 0, &Error{err: "message too large"}
}
l := make([]byte, 2, lp+2)
binary.BigEndian.PutUint16(l, uint16(lp))
p = append(l, p...)
n, err := io.Copy(w, bytes.NewReader(p))
return int(n), err
}
n, err = co.Conn.Write(p)
return n, err
func (co *Conn) Write(p []byte) (int, error) {
if len(p) > MaxMsgSize {
return 0, &Error{err: "message too large"}
}
if isPacketConn(co.Conn) {
return co.Conn.Write(p)
}
msg := make([]byte, 2+len(p))
binary.BigEndian.PutUint16(msg, uint16(len(p)))
copy(msg[2:], p)
return co.Conn.Write(msg)
}
// Return the appropriate timeout for a specific request
......@@ -499,14 +418,14 @@ func Dial(network, address string) (conn *Conn, err error) {
func ExchangeContext(ctx context.Context, m *Msg, a string) (r *Msg, err error) {
client := Client{Net: "udp"}
r, _, err = client.ExchangeContext(ctx, m, a)
// ignorint rtt to leave the original ExchangeContext API unchanged, but
// ignoring rtt to leave the original ExchangeContext API unchanged, but
// this function will go away
return r, err
}
// ExchangeConn performs a synchronous query. It sends the message m via the connection
// c and waits for a reply. The connection c is not closed by ExchangeConn.
// This function is going away, but can easily be mimicked:
// Deprecated: This function is going away, but can easily be mimicked:
//
// co := &dns.Conn{Conn: c} // c is your net.Conn
// co.WriteMsg(m)
......@@ -530,11 +449,7 @@ func ExchangeConn(c net.Conn, m *Msg) (r *Msg, err error) {
// DialTimeout acts like Dial but takes a timeout.
func DialTimeout(network, address string, timeout time.Duration) (conn *Conn, err error) {
client := Client{Net: network, Dialer: &net.Dialer{Timeout: timeout}}
conn, err = client.Dial(address)
if err != nil {
return nil, err
}
return conn, nil
return client.Dial(address)
}
// DialWithTLS connects to the address on the named network with TLS.
......@@ -543,12 +458,7 @@ func DialWithTLS(network, address string, tlsConfig *tls.Config) (conn *Conn, er
network += "-tls"
}
client := Client{Net: network, TLSConfig: tlsConfig}
conn, err = client.Dial(address)
if err != nil {
return nil, err
}
return conn, nil
return client.Dial(address)
}
// DialTimeoutWithTLS acts like DialWithTLS but takes a timeout.
......@@ -557,30 +467,18 @@ func DialTimeoutWithTLS(network, address string, tlsConfig *tls.Config, timeout
network += "-tls"
}
client := Client{Net: network, Dialer: &net.Dialer{Timeout: timeout}, TLSConfig: tlsConfig}
conn, err = client.Dial(address)
if err != nil {
return nil, err
}
return conn, nil
return client.Dial(address)
}
// ExchangeContext acts like Exchange, but honors the deadline on the provided
// context, if present. If there is both a context deadline and a configured
// timeout on the client, the earliest of the two takes effect.
func (c *Client) ExchangeContext(ctx context.Context, m *Msg, a string) (r *Msg, rtt time.Duration, err error) {
if !c.SingleInflight && c.Net == "https" {
return c.exchangeDOH(ctx, m, a)
conn, err := c.DialContext(ctx, a)
if err != nil {
return nil, 0, err
}
defer conn.Close()
var timeout time.Duration
if deadline, ok := ctx.Deadline(); !ok {
timeout = 0
} else {
timeout = deadline.Sub(time.Now())
}
// not passing the context to the underlying calls, as the API does not support
// context. For timeouts you should set up Client.Dialer and call Client.Exchange.
// TODO(tmthrgd): this is a race condition
c.Dialer = &net.Dialer{Timeout: timeout}
return c.Exchange(m, a)
return c.exchangeWithConnContext(ctx, m, conn)
}
......@@ -68,14 +68,10 @@ func ClientConfigFromReader(resolvconf io.Reader) (*ClientConfig, error) {
}
case "search": // set search path to given servers
c.Search = make([]string, len(f)-1)
for i := 0; i < len(c.Search); i++ {
c.Search[i] = f[i+1]
}
c.Search = append([]string(nil), f[1:]...)
case "options": // magic options
for i := 1; i < len(f); i++ {
s := f[i]
for _, s := range f[1:] {
switch {
case len(s) >= 6 && s[:6] == "ndots:":
n, _ := strconv.Atoi(s[6:])
......
//+build ignore
// compression_generate.go is meant to run with go generate. It will use
// go/{importer,types} to track down all the RR struct types. Then for each type
// it will look to see if there are (compressible) names, if so it will add that
// type to compressionLenHelperType and comressionLenSearchType which "fake" the
// compression so that Len() is fast.
package main
import (
"bytes"
"fmt"
"go/format"
"go/importer"
"go/types"
"log"
"os"
)
var packageHdr = `
// Code generated by "go run compress_generate.go"; DO NOT EDIT.
package dns
`
// getTypeStruct will take a type and the package scope, and return the
// (innermost) struct if the type is considered a RR type (currently defined as
// those structs beginning with a RR_Header, could be redefined as implementing
// the RR interface). The bool return value indicates if embedded structs were
// resolved.
func getTypeStruct(t types.Type, scope *types.Scope) (*types.Struct, bool) {
st, ok := t.Underlying().(*types.Struct)
if !ok {
return nil, false
}
if st.Field(0).Type() == scope.Lookup("RR_Header").Type() {
return st, false
}
if st.Field(0).Anonymous() {
st, _ := getTypeStruct(st.Field(0).Type(), scope)
return st, true
}
return nil, false
}
func main() {
// Import and type-check the package
pkg, err := importer.Default().Import("github.com/miekg/dns")
fatalIfErr(err)
scope := pkg.Scope()
var domainTypes []string // Types that have a domain name in them (either compressible or not).
var cdomainTypes []string // Types that have a compressible domain name in them (subset of domainType)
Names:
for _, name := range scope.Names() {
o := scope.Lookup(name)
if o == nil || !o.Exported() {
continue
}
st, _ := getTypeStruct(o.Type(), scope)
if st == nil {
continue
}
if name == "PrivateRR" {
continue
}
if scope.Lookup("Type"+o.Name()) == nil && o.Name() != "RFC3597" {
log.Fatalf("Constant Type%s does not exist.", o.Name())
}
for i := 1; i < st.NumFields(); i++ {
if _, ok := st.Field(i).Type().(*types.Slice); ok {
if st.Tag(i) == `dns:"domain-name"` {
domainTypes = append(domainTypes, o.Name())
continue Names
}
if st.Tag(i) == `dns:"cdomain-name"` {
cdomainTypes = append(cdomainTypes, o.Name())
domainTypes = append(domainTypes, o.Name())
continue Names
}
continue
}
switch {
case st.Tag(i) == `dns:"domain-name"`:
domainTypes = append(domainTypes, o.Name())
continue Names
case st.Tag(i) == `dns:"cdomain-name"`:
cdomainTypes = append(cdomainTypes, o.Name())
domainTypes = append(domainTypes, o.Name())
continue Names
}
}
}
b := &bytes.Buffer{}
b.WriteString(packageHdr)
// compressionLenHelperType - all types that have domain-name/cdomain-name can be used for compressing names
fmt.Fprint(b, "func compressionLenHelperType(c map[string]int, r RR, initLen int) int {\n")
fmt.Fprint(b, "currentLen := initLen\n")
fmt.Fprint(b, "switch x := r.(type) {\n")
for _, name := range domainTypes {
o := scope.Lookup(name)
st, _ := getTypeStruct(o.Type(), scope)
fmt.Fprintf(b, "case *%s:\n", name)
for i := 1; i < st.NumFields(); i++ {
out := func(s string) {
fmt.Fprintf(b, "currentLen -= len(x.%s) + 1\n", st.Field(i).Name())
fmt.Fprintf(b, "currentLen += compressionLenHelper(c, x.%s, currentLen)\n", st.Field(i).Name())
}
if _, ok := st.Field(i).Type().(*types.Slice); ok {
switch st.Tag(i) {
case `dns:"domain-name"`:
fallthrough
case `dns:"cdomain-name"`:
// For HIP we need to slice over the elements in this slice.
fmt.Fprintf(b, `for i := range x.%s {
currentLen -= len(x.%s[i]) + 1
}
`, st.Field(i).Name(), st.Field(i).Name())
fmt.Fprintf(b, `for i := range x.%s {
currentLen += compressionLenHelper(c, x.%s[i], currentLen)
}
`, st.Field(i).Name(), st.Field(i).Name())
}
continue
}
switch {
case st.Tag(i) == `dns:"cdomain-name"`:
fallthrough
case st.Tag(i) == `dns:"domain-name"`:
out(st.Field(i).Name())
}
}
}
fmt.Fprintln(b, "}\nreturn currentLen - initLen\n}\n\n")
// compressionLenSearchType - search cdomain-tags types for compressible names.
fmt.Fprint(b, "func compressionLenSearchType(c map[string]int, r RR) (int, bool, int) {\n")
fmt.Fprint(b, "switch x := r.(type) {\n")
for _, name := range cdomainTypes {
o := scope.Lookup(name)
st, _ := getTypeStruct(o.Type(), scope)
fmt.Fprintf(b, "case *%s:\n", name)
j := 1
for i := 1; i < st.NumFields(); i++ {
out := func(s string, j int) {
fmt.Fprintf(b, "k%d, ok%d, sz%d := compressionLenSearch(c, x.%s)\n", j, j, j, st.Field(i).Name())
}
// There are no slice types with names that can be compressed.
switch {
case st.Tag(i) == `dns:"cdomain-name"`:
out(st.Field(i).Name(), j)
j++
}
}
k := "k1"
ok := "ok1"
sz := "sz1"
for i := 2; i < j; i++ {
k += fmt.Sprintf(" + k%d", i)
ok += fmt.Sprintf(" && ok%d", i)
sz += fmt.Sprintf(" + sz%d", i)
}
fmt.Fprintf(b, "return %s, %s, %s\n", k, ok, sz)
}
fmt.Fprintln(b, "}\nreturn 0, false, 0\n}\n\n")
// gofmt
res, err := format.Source(b.Bytes())
if err != nil {
b.WriteTo(os.Stderr)
log.Fatal(err)
}
f, err := os.Create("zcompress.go")
fatalIfErr(err)
defer f.Close()
f.Write(res)
}
func fatalIfErr(err error) {
if err != nil {
log.Fatal(err)
}
}
......@@ -4,6 +4,7 @@ import (
"errors"
"net"
"strconv"
"strings"
)
const hexDigit = "0123456789abcdef"
......@@ -104,7 +105,7 @@ func (dns *Msg) SetAxfr(z string) *Msg {
// SetTsig appends a TSIG RR to the message.
// This is only a skeleton TSIG RR that is added as the last RR in the
// additional section. The Tsig is calculated when the message is being send.
// additional section. The TSIG is calculated when the message is being send.
func (dns *Msg) SetTsig(z, algo string, fudge uint16, timesigned int64) *Msg {
t := new(TSIG)
t.Hdr = RR_Header{z, TypeTSIG, ClassANY, 0, 0}
......@@ -145,10 +146,9 @@ func (dns *Msg) IsTsig() *TSIG {
// record in the additional section will do. It returns the OPT record
// found or nil.
func (dns *Msg) IsEdns0() *OPT {
// EDNS0 is at the end of the additional section, start there.
// We might want to change this to *only* look at the last two
// records. So we see TSIG and/or OPT - this a slightly bigger
// change though.
// RFC 6891, Section 6.1.1 allows the OPT record to appear
// anywhere in the additional record section, but it's usually at
// the end so start there.
for i := len(dns.Extra) - 1; i >= 0; i-- {
if dns.Extra[i].Header().Rrtype == TypeOPT {
return dns.Extra[i].(*OPT)
......@@ -157,17 +157,98 @@ func (dns *Msg) IsEdns0() *OPT {
return nil
}
// popEdns0 is like IsEdns0, but it removes the record from the message.
func (dns *Msg) popEdns0() *OPT {
// RFC 6891, Section 6.1.1 allows the OPT record to appear
// anywhere in the additional record section, but it's usually at
// the end so start there.
for i := len(dns.Extra) - 1; i >= 0; i-- {
if dns.Extra[i].Header().Rrtype == TypeOPT {
opt := dns.Extra[i].(*OPT)
dns.Extra = append(dns.Extra[:i], dns.Extra[i+1:]...)
return opt
}
}
return nil
}
// IsDomainName checks if s is a valid domain name, it returns the number of
// labels and true, when a domain name is valid. Note that non fully qualified
// domain name is considered valid, in this case the last label is counted in
// the number of labels. When false is returned the number of labels is not
// defined. Also note that this function is extremely liberal; almost any
// string is a valid domain name as the DNS is 8 bit protocol. It checks if each
// label fits in 63 characters, but there is no length check for the entire
// string s. I.e. a domain name longer than 255 characters is considered valid.
// label fits in 63 characters and that the entire name will fit into the 255
// octet wire format limit.
func IsDomainName(s string) (labels int, ok bool) {
_, labels, err := packDomainName(s, nil, 0, nil, false)
return labels, err == nil
// XXX: The logic in this function was copied from packDomainName and
// should be kept in sync with that function.
const lenmsg = 256
if len(s) == 0 { // Ok, for instance when dealing with update RR without any rdata.
return 0, false
}
s = Fqdn(s)
// Each dot ends a segment of the name. Except for escaped dots (\.), which
// are normal dots.
var (
off int
begin int
wasDot bool
)
for i := 0; i < len(s); i++ {
switch s[i] {
case '\\':
if off+1 > lenmsg {
return labels, false
}
// check for \DDD
if i+3 < len(s) && isDigit(s[i+1]) && isDigit(s[i+2]) && isDigit(s[i+3]) {
i += 3
begin += 3
} else {
i++
begin++
}
wasDot = false
case '.':
if i == 0 && len(s) > 1 {
// leading dots are not legal except for the root zone
return labels, false
}
if wasDot {
// two dots back to back is not legal
return labels, false
}
wasDot = true
labelLen := i - begin
if labelLen >= 1<<6 { // top two bits of length must be clear
return labels, false
}
// off can already (we're in a loop) be bigger than lenmsg
// this happens when a name isn't fully qualified
off += 1 + labelLen
if off > lenmsg {
return labels, false
}
labels++
begin = i + 1
default:
wasDot = false
}
}
return labels, true
}
// IsSubDomain checks if child is indeed a child of the parent. If child and parent
......@@ -181,7 +262,7 @@ func IsSubDomain(parent, child string) bool {
// The checking is performed on the binary payload.
func IsMsg(buf []byte) error {
// Header
if len(buf) < 12 {
if len(buf) < headerSize {
return errors.New("dns: bad message header")
}
// Header: Opcode
......@@ -191,11 +272,18 @@ func IsMsg(buf []byte) error {
// IsFqdn checks if a domain name is fully qualified.
func IsFqdn(s string) bool {
l := len(s)
if l == 0 {
s2 := strings.TrimSuffix(s, ".")
if s == s2 {
return false
}
return s[l-1] == '.'
i := strings.LastIndexFunc(s2, func(r rune) bool {
return r != '\\'
})
// Test whether we have an even number of escape sequences before
// the dot or none.
return (len(s2)-i)%2 != 0
}
// IsRRset checks if a set of RRs is a valid RRset as defined by RFC 2181.
......@@ -234,6 +322,12 @@ func Fqdn(s string) string {
return s + "."
}
// CanonicalName returns the domain name in canonical form. A name in canonical
// form is lowercase and fully qualified. See Section 6.2 in RFC 4034.
func CanonicalName(s string) string {
return strings.ToLower(Fqdn(s))
}
// Copied from the official Go code.
// ReverseAddr returns the in-addr.arpa. or ip6.arpa. hostname of the IP
......@@ -244,19 +338,23 @@ func ReverseAddr(addr string) (arpa string, err error) {
if ip == nil {
return "", &Error{err: "unrecognized address: " + addr}
}
if ip.To4() != nil {
return strconv.Itoa(int(ip[15])) + "." + strconv.Itoa(int(ip[14])) + "." + strconv.Itoa(int(ip[13])) + "." +
strconv.Itoa(int(ip[12])) + ".in-addr.arpa.", nil
if v4 := ip.To4(); v4 != nil {
buf := make([]byte, 0, net.IPv4len*4+len("in-addr.arpa."))
// Add it, in reverse, to the buffer
for i := len(v4) - 1; i >= 0; i-- {
buf = strconv.AppendInt(buf, int64(v4[i]), 10)
buf = append(buf, '.')
}
// Append "in-addr.arpa." and return (buf already has the final .)
buf = append(buf, "in-addr.arpa."...)
return string(buf), nil
}
// Must be IPv6
buf := make([]byte, 0, len(ip)*4+len("ip6.arpa."))
buf := make([]byte, 0, net.IPv6len*4+len("ip6.arpa."))
// Add it, in reverse, to the buffer
for i := len(ip) - 1; i >= 0; i-- {
v := ip[i]
buf = append(buf, hexDigit[v&0xF])
buf = append(buf, '.')
buf = append(buf, hexDigit[v>>4])
buf = append(buf, '.')
buf = append(buf, hexDigit[v&0xF], '.', hexDigit[v>>4], '.')
}
// Append "ip6.arpa." and return (buf already has the final .)
buf = append(buf, "ip6.arpa."...)
......@@ -274,7 +372,7 @@ func (t Type) String() string {
// String returns the string representation for the class c.
func (c Class) String() string {
if s, ok := ClassToString[uint16(c)]; ok {
// Only emit mnemonics when they are unambiguous, specically ANY is in both.
// Only emit mnemonics when they are unambiguous, specially ANY is in both.
if _, ok := StringToType[s]; !ok {
return s
}
......
package dns
import "strconv"
import (
"encoding/hex"
"strconv"
)
const (
year68 = 1 << 31 // For RFC1982 (Serial Arithmetic) calculations in 32 bits.
......@@ -34,10 +37,30 @@ type RR interface {
// copy returns a copy of the RR
copy() RR
// len returns the length (in octets) of the uncompressed RR in wire format.
len() int
// pack packs an RR into wire format.
pack([]byte, int, map[string]int, bool) (int, error)
// len returns the length (in octets) of the compressed or uncompressed RR in wire format.
//
// If compression is nil, the uncompressed size will be returned, otherwise the compressed
// size will be returned and domain names will be added to the map for future compression.
len(off int, compression map[string]struct{}) int
// pack packs the records RDATA into wire format. The header will
// already have been packed into msg.
pack(msg []byte, off int, compression compressionMap, compress bool) (off1 int, err error)
// unpack unpacks an RR from wire format.
//
// This will only be called on a new and empty RR type with only the header populated. It
// will only be called if the record's RDATA is non-empty.
unpack(msg []byte, off int) (off1 int, err error)
// parse parses an RR from zone file format.
//
// This will only be called on a new and empty RR type with only the header populated.
parse(c *zlexer, origin string) *ParseError
// isDuplicate returns whether the two RRs are duplicates.
isDuplicate(r2 RR) bool
}
// RR_Header is the header all DNS resource records share.
......@@ -70,28 +93,66 @@ func (h *RR_Header) String() string {
return s
}
func (h *RR_Header) len() int {
l := len(h.Name) + 1
func (h *RR_Header) len(off int, compression map[string]struct{}) int {
l := domainNameLen(h.Name, off, compression, true)
l += 10 // rrtype(2) + class(2) + ttl(4) + rdlength(2)
return l
}
func (h *RR_Header) pack(msg []byte, off int, compression compressionMap, compress bool) (off1 int, err error) {
// RR_Header has no RDATA to pack.
return off, nil
}
func (h *RR_Header) unpack(msg []byte, off int) (int, error) {
panic("dns: internal error: unpack should never be called on RR_Header")
}
func (h *RR_Header) parse(c *zlexer, origin string) *ParseError {
panic("dns: internal error: parse should never be called on RR_Header")
}
// ToRFC3597 converts a known RR to the unknown RR representation from RFC 3597.
func (rr *RFC3597) ToRFC3597(r RR) error {
buf := make([]byte, r.len()*2)
off, err := PackRR(r, buf, 0, nil, false)
buf := make([]byte, Len(r))
headerEnd, off, err := packRR(r, buf, 0, compressionMap{}, false)
if err != nil {
return err
}
buf = buf[:off]
if int(r.Header().Rdlength) > off {
return ErrBuf
*rr = RFC3597{Hdr: *r.Header()}
rr.Hdr.Rdlength = uint16(off - headerEnd)
if noRdata(rr.Hdr) {
return nil
}
_, err = rr.unpack(buf, headerEnd)
return err
}
// fromRFC3597 converts an unknown RR representation from RFC 3597 to the known RR type.
func (rr *RFC3597) fromRFC3597(r RR) error {
hdr := r.Header()
*hdr = rr.Hdr
// Can't overflow uint16 as the length of Rdata is validated in (*RFC3597).parse.
// We can only get here when rr was constructed with that method.
hdr.Rdlength = uint16(hex.DecodedLen(len(rr.Rdata)))
if noRdata(*hdr) {
// Dynamic update.
return nil
}
rfc3597, _, err := unpackRFC3597(*r.Header(), buf, off-int(r.Header().Rdlength))
// rr.pack requires an extra allocation and a copy so we just decode Rdata
// manually, it's simpler anyway.
msg, err := hex.DecodeString(rr.Rdata)
if err != nil {
return err
}
*rr = *rfc3597.(*RFC3597)
return nil
_, err = r.unpack(msg, 0)
return err
}
......@@ -3,15 +3,14 @@ package dns
import (
"bytes"
"crypto"
"crypto/dsa"
"crypto/ecdsa"
"crypto/ed25519"
"crypto/elliptic"
_ "crypto/md5"
"crypto/rand"
"crypto/rsa"
_ "crypto/sha1"
_ "crypto/sha256"
_ "crypto/sha512"
_ "crypto/sha1" // need its init function
_ "crypto/sha256" // need its init function
_ "crypto/sha512" // need its init function
"encoding/asn1"
"encoding/binary"
"encoding/hex"
......@@ -19,8 +18,6 @@ import (
"sort"
"strings"
"time"
"golang.org/x/crypto/ed25519"
)
// DNSSEC encryption algorithm codes.
......@@ -67,10 +64,10 @@ var AlgorithmToString = map[uint8]string{
PRIVATEOID: "PRIVATEOID",
}
// StringToAlgorithm is the reverse of AlgorithmToString.
var StringToAlgorithm = reverseInt8(AlgorithmToString)
// AlgorithmToHash is a map of algorithm crypto hash IDs to crypto.Hash's.
// For newer algorithm that do their own hashing (i.e. ED25519) the returned value
// is 0, implying no (external) hashing should occur. The non-exported identityHash is then
// used.
var AlgorithmToHash = map[uint8]crypto.Hash{
RSAMD5: crypto.MD5, // Deprecated in RFC 6725
DSA: crypto.SHA1,
......@@ -80,7 +77,7 @@ var AlgorithmToHash = map[uint8]crypto.Hash{
ECDSAP256SHA256: crypto.SHA256,
ECDSAP384SHA384: crypto.SHA384,
RSASHA512: crypto.SHA512,
ED25519: crypto.Hash(0),
ED25519: 0,
}
// DNSSEC hashing algorithm codes.
......@@ -102,9 +99,6 @@ var HashToString = map[uint8]string{
SHA512: "SHA512",
}
// StringToHash is a map of names to hash IDs.
var StringToHash = reverseInt8(HashToString)
// DNSKEY flag values.
const (
SEP = 1
......@@ -146,12 +140,12 @@ func (k *DNSKEY) KeyTag() uint16 {
var keytag int
switch k.Algorithm {
case RSAMD5:
// Look at the bottom two bytes of the modules, which the last
// item in the pubkey. We could do this faster by looking directly
// at the base64 values. But I'm lazy.
// This algorithm has been deprecated, but keep this key-tag calculation.
// Look at the bottom two bytes of the modules, which the last item in the pubkey.
// See https://www.rfc-editor.org/errata/eid193 .
modulus, _ := fromBase64([]byte(k.PublicKey))
if len(modulus) > 1 {
x := binary.BigEndian.Uint16(modulus[len(modulus)-2:])
x := binary.BigEndian.Uint16(modulus[len(modulus)-3:])
keytag = int(x)
}
default:
......@@ -206,7 +200,7 @@ func (k *DNSKEY) ToDS(h uint8) *DS {
wire = wire[:n]
owner := make([]byte, 255)
off, err1 := PackDomainName(strings.ToLower(k.Hdr.Name), owner, 0, nil, false)
off, err1 := PackDomainName(CanonicalName(k.Hdr.Name), owner, 0, nil, false)
if err1 != nil {
return nil
}
......@@ -268,16 +262,17 @@ func (rr *RRSIG) Sign(k crypto.Signer, rrset []RR) error {
return ErrKey
}
h0 := rrset[0].Header()
rr.Hdr.Rrtype = TypeRRSIG
rr.Hdr.Name = rrset[0].Header().Name
rr.Hdr.Class = rrset[0].Header().Class
rr.Hdr.Name = h0.Name
rr.Hdr.Class = h0.Class
if rr.OrigTtl == 0 { // If set don't override
rr.OrigTtl = rrset[0].Header().Ttl
rr.OrigTtl = h0.Ttl
}
rr.TypeCovered = rrset[0].Header().Rrtype
rr.Labels = uint8(CountLabel(rrset[0].Header().Name))
rr.TypeCovered = h0.Rrtype
rr.Labels = uint8(CountLabel(h0.Name))
if strings.HasPrefix(rrset[0].Header().Name, "*") {
if strings.HasPrefix(h0.Name, "*") {
rr.Labels-- // wildcard, remove from label count
}
......@@ -290,7 +285,7 @@ func (rr *RRSIG) Sign(k crypto.Signer, rrset []RR) error {
sigwire.Inception = rr.Inception
sigwire.KeyTag = rr.KeyTag
// For signing, lowercase this name
sigwire.SignerName = strings.ToLower(rr.SignerName)
sigwire.SignerName = CanonicalName(rr.SignerName)
// Create the desired binary blob
signdata := make([]byte, DefaultMsgSize)
......@@ -304,39 +299,27 @@ func (rr *RRSIG) Sign(k crypto.Signer, rrset []RR) error {
return err
}
hash, ok := AlgorithmToHash[rr.Algorithm]
if !ok {
return ErrAlg
h, cryptohash, err := hashFromAlgorithm(rr.Algorithm)
if err != nil {
return err
}
switch rr.Algorithm {
case ED25519:
// ed25519 signs the raw message and performs hashing internally.
// All other supported signature schemes operate over the pre-hashed
// message, and thus ed25519 must be handled separately here.
//
// The raw message is passed directly into sign and crypto.Hash(0) is
// used to signal to the crypto.Signer that the data has not been hashed.
signature, err := sign(k, append(signdata, wire...), crypto.Hash(0), rr.Algorithm)
if err != nil {
return err
}
rr.Signature = toBase64(signature)
case RSAMD5, DSA, DSANSEC3SHA1:
// See RFC 6944.
return ErrAlg
default:
h := hash.New()
h.Write(signdata)
h.Write(wire)
signature, err := sign(k, h.Sum(nil), hash, rr.Algorithm)
signature, err := sign(k, h.Sum(nil), cryptohash, rr.Algorithm)
if err != nil {
return err
}
rr.Signature = toBase64(signature)
return nil
}
return nil
}
func sign(k crypto.Signer, hashed []byte, hash crypto.Hash, alg uint8) ([]byte, error) {
......@@ -346,9 +329,8 @@ func sign(k crypto.Signer, hashed []byte, hash crypto.Hash, alg uint8) ([]byte,
}
switch alg {
case RSASHA1, RSASHA1NSEC3SHA1, RSASHA256, RSASHA512:
case RSASHA1, RSASHA1NSEC3SHA1, RSASHA256, RSASHA512, ED25519:
return signature, nil
case ECDSAP256SHA256, ECDSAP384SHA384:
ecdsaSignature := &struct {
R, S *big.Int
......@@ -368,25 +350,16 @@ func sign(k crypto.Signer, hashed []byte, hash crypto.Hash, alg uint8) ([]byte,
signature := intToBytes(ecdsaSignature.R, intlen)
signature = append(signature, intToBytes(ecdsaSignature.S, intlen)...)
return signature, nil
// There is no defined interface for what a DSA backed crypto.Signer returns
case DSA, DSANSEC3SHA1:
// t := divRoundUp(divRoundUp(p.PublicKey.Y.BitLen(), 8)-64, 8)
// signature := []byte{byte(t)}
// signature = append(signature, intToBytes(r1, 20)...)
// signature = append(signature, intToBytes(s1, 20)...)
// rr.Signature = signature
case ED25519:
return signature, nil
default:
return nil, ErrAlg
}
return nil, ErrAlg
}
// Verify validates an RRSet with the signature and key. This is only the
// cryptographic test, the signature validity period must be checked separately.
// This function copies the rdata of some RRs (to lowercase domain names) for the validation to work.
// It also checks that the Zone Key bit (RFC 4034 2.1.1) is set on the DNSKEY
// and that the Protocol field is set to 3 (RFC 4034 2.1.2).
func (rr *RRSIG) Verify(k *DNSKEY, rrset []RR) error {
// First the easy checks
if !IsRRset(rrset) {
......@@ -401,20 +374,23 @@ func (rr *RRSIG) Verify(k *DNSKEY, rrset []RR) error {
if rr.Algorithm != k.Algorithm {
return ErrKey
}
if strings.ToLower(rr.SignerName) != strings.ToLower(k.Hdr.Name) {
if !strings.EqualFold(rr.SignerName, k.Hdr.Name) {
return ErrKey
}
if k.Protocol != 3 {
return ErrKey
}
// RFC 4034 2.1.1 If bit 7 has value 0, then the DNSKEY record holds some
// other type of DNS public key and MUST NOT be used to verify RRSIGs that
// cover RRsets.
if k.Flags&ZONE == 0 {
return ErrKey
}
// IsRRset checked that we have at least one RR and that the RRs in
// the set have consistent type, class, and name. Also check that type and
// class matches the RRSIG record.
if rrset[0].Header().Class != rr.Hdr.Class {
return ErrRRset
}
if rrset[0].Header().Rrtype != rr.TypeCovered {
if h0 := rrset[0].Header(); h0.Class != rr.Hdr.Class || h0.Rrtype != rr.TypeCovered {
return ErrRRset
}
......@@ -428,7 +404,7 @@ func (rr *RRSIG) Verify(k *DNSKEY, rrset []RR) error {
sigwire.Expiration = rr.Expiration
sigwire.Inception = rr.Inception
sigwire.KeyTag = rr.KeyTag
sigwire.SignerName = strings.ToLower(rr.SignerName)
sigwire.SignerName = CanonicalName(rr.SignerName)
// Create the desired binary blob
signeddata := make([]byte, DefaultMsgSize)
n, err := packSigWire(sigwire, signeddata)
......@@ -447,23 +423,22 @@ func (rr *RRSIG) Verify(k *DNSKEY, rrset []RR) error {
// remove the domain name and assume its ours?
}
hash, ok := AlgorithmToHash[rr.Algorithm]
if !ok {
return ErrAlg
h, cryptohash, err := hashFromAlgorithm(rr.Algorithm)
if err != nil {
return err
}
switch rr.Algorithm {
case RSASHA1, RSASHA1NSEC3SHA1, RSASHA256, RSASHA512, RSAMD5:
case RSASHA1, RSASHA1NSEC3SHA1, RSASHA256, RSASHA512:
// TODO(mg): this can be done quicker, ie. cache the pubkey data somewhere??
pubkey := k.publicKeyRSA() // Get the key
if pubkey == nil {
return ErrKey
}
h := hash.New()
h.Write(signeddata)
h.Write(wire)
return rsa.VerifyPKCS1v15(pubkey, hash, h.Sum(nil), sigbuf)
return rsa.VerifyPKCS1v15(pubkey, cryptohash, h.Sum(nil), sigbuf)
case ECDSAP256SHA256, ECDSAP384SHA384:
pubkey := k.publicKeyECDSA()
......@@ -475,7 +450,6 @@ func (rr *RRSIG) Verify(k *DNSKEY, rrset []RR) error {
r := new(big.Int).SetBytes(sigbuf[:len(sigbuf)/2])
s := new(big.Int).SetBytes(sigbuf[len(sigbuf)/2:])
h := hash.New()
h.Write(signeddata)
h.Write(wire)
if ecdsa.Verify(pubkey, h.Sum(nil), r, s) {
......@@ -517,7 +491,7 @@ func (rr *RRSIG) ValidityPeriod(t time.Time) bool {
return ti <= utc && utc <= te
}
// Return the signatures base64 encodedig sigdata as a byte slice.
// Return the signatures base64 encoding sigdata as a byte slice.
func (rr *RRSIG) sigBuf() []byte {
sigbuf, err := fromBase64([]byte(rr.Signature))
if err != nil {
......@@ -563,20 +537,19 @@ func (k *DNSKEY) publicKeyRSA() *rsa.PublicKey {
pubkey := new(rsa.PublicKey)
expo := uint64(0)
for i := 0; i < int(explen); i++ {
var expo uint64
// The exponent of length explen is between keyoff and modoff.
for _, v := range keybuf[keyoff:modoff] {
expo <<= 8
expo |= uint64(keybuf[keyoff+i])
expo |= uint64(v)
}
if expo > 1<<31-1 {
// Larger exponent than supported by the crypto package.
return nil
}
pubkey.E = int(expo)
pubkey.N = big.NewInt(0)
pubkey.N.SetBytes(keybuf[modoff:])
pubkey.E = int(expo)
pubkey.N = new(big.Int).SetBytes(keybuf[modoff:])
return pubkey
}
......@@ -601,34 +574,8 @@ func (k *DNSKEY) publicKeyECDSA() *ecdsa.PublicKey {
return nil
}
}
pubkey.X = big.NewInt(0)
pubkey.X.SetBytes(keybuf[:len(keybuf)/2])
pubkey.Y = big.NewInt(0)
pubkey.Y.SetBytes(keybuf[len(keybuf)/2:])
return pubkey
}
func (k *DNSKEY) publicKeyDSA() *dsa.PublicKey {
keybuf, err := fromBase64([]byte(k.PublicKey))
if err != nil {
return nil
}
if len(keybuf) < 22 {
return nil
}
t, keybuf := int(keybuf[0]), keybuf[1:]
size := 64 + t*8
q, keybuf := keybuf[:20], keybuf[20:]
if len(keybuf) != 3*size {
return nil
}
p, keybuf := keybuf[:size], keybuf[size:]
g, y := keybuf[:size], keybuf[size:]
pubkey := new(dsa.PublicKey)
pubkey.Parameters.Q = big.NewInt(0).SetBytes(q)
pubkey.Parameters.P = big.NewInt(0).SetBytes(p)
pubkey.Parameters.G = big.NewInt(0).SetBytes(g)
pubkey.Y = big.NewInt(0).SetBytes(y)
pubkey.X = new(big.Int).SetBytes(keybuf[:len(keybuf)/2])
pubkey.Y = new(big.Int).SetBytes(keybuf[len(keybuf)/2:])
return pubkey
}
......@@ -658,15 +605,16 @@ func rawSignatureData(rrset []RR, s *RRSIG) (buf []byte, err error) {
wires := make(wireSlice, len(rrset))
for i, r := range rrset {
r1 := r.copy()
r1.Header().Ttl = s.OrigTtl
labels := SplitDomainName(r1.Header().Name)
h := r1.Header()
h.Ttl = s.OrigTtl
labels := SplitDomainName(h.Name)
// 6.2. Canonical RR Form. (4) - wildcards
if len(labels) > int(s.Labels) {
// Wildcard
r1.Header().Name = "*." + strings.Join(labels[len(labels)-int(s.Labels):], ".") + "."
h.Name = "*." + strings.Join(labels[len(labels)-int(s.Labels):], ".") + "."
}
// RFC 4034: 6.2. Canonical RR Form. (2) - domain name to lowercase
r1.Header().Name = strings.ToLower(r1.Header().Name)
h.Name = CanonicalName(h.Name)
// 6.2. Canonical RR Form. (3) - domain rdata to lowercase.
// NS, MD, MF, CNAME, SOA, MB, MG, MR, PTR,
// HINFO, MINFO, MX, RP, AFSDB, RT, SIG, PX, NXT, NAPTR, KX,
......@@ -679,52 +627,52 @@ func rawSignatureData(rrset []RR, s *RRSIG) (buf []byte, err error) {
// conversion.
switch x := r1.(type) {
case *NS:
x.Ns = strings.ToLower(x.Ns)
x.Ns = CanonicalName(x.Ns)
case *MD:
x.Md = strings.ToLower(x.Md)
x.Md = CanonicalName(x.Md)
case *MF:
x.Mf = strings.ToLower(x.Mf)
x.Mf = CanonicalName(x.Mf)
case *CNAME:
x.Target = strings.ToLower(x.Target)
x.Target = CanonicalName(x.Target)
case *SOA:
x.Ns = strings.ToLower(x.Ns)
x.Mbox = strings.ToLower(x.Mbox)
x.Ns = CanonicalName(x.Ns)
x.Mbox = CanonicalName(x.Mbox)
case *MB:
x.Mb = strings.ToLower(x.Mb)
x.Mb = CanonicalName(x.Mb)
case *MG:
x.Mg = strings.ToLower(x.Mg)
x.Mg = CanonicalName(x.Mg)
case *MR:
x.Mr = strings.ToLower(x.Mr)
x.Mr = CanonicalName(x.Mr)
case *PTR:
x.Ptr = strings.ToLower(x.Ptr)
x.Ptr = CanonicalName(x.Ptr)
case *MINFO:
x.Rmail = strings.ToLower(x.Rmail)
x.Email = strings.ToLower(x.Email)
x.Rmail = CanonicalName(x.Rmail)
x.Email = CanonicalName(x.Email)
case *MX:
x.Mx = strings.ToLower(x.Mx)
x.Mx = CanonicalName(x.Mx)
case *RP:
x.Mbox = strings.ToLower(x.Mbox)
x.Txt = strings.ToLower(x.Txt)
x.Mbox = CanonicalName(x.Mbox)
x.Txt = CanonicalName(x.Txt)
case *AFSDB:
x.Hostname = strings.ToLower(x.Hostname)
x.Hostname = CanonicalName(x.Hostname)
case *RT:
x.Host = strings.ToLower(x.Host)
x.Host = CanonicalName(x.Host)
case *SIG:
x.SignerName = strings.ToLower(x.SignerName)
x.SignerName = CanonicalName(x.SignerName)
case *PX:
x.Map822 = strings.ToLower(x.Map822)
x.Mapx400 = strings.ToLower(x.Mapx400)
x.Map822 = CanonicalName(x.Map822)
x.Mapx400 = CanonicalName(x.Mapx400)
case *NAPTR:
x.Replacement = strings.ToLower(x.Replacement)
x.Replacement = CanonicalName(x.Replacement)
case *KX:
x.Exchanger = strings.ToLower(x.Exchanger)
x.Exchanger = CanonicalName(x.Exchanger)
case *SRV:
x.Target = strings.ToLower(x.Target)
x.Target = CanonicalName(x.Target)
case *DNAME:
x.Target = strings.ToLower(x.Target)
x.Target = CanonicalName(x.Target)
}
// 6.2. Canonical RR Form. (5) - origTTL
wire := make([]byte, r1.len()+1) // +1 to be safe(r)
wire := make([]byte, Len(r1)+1) // +1 to be safe(r)
off, err1 := PackRR(r1, wire, 0, nil, false)
if err1 != nil {
return nil, err1
......
......@@ -2,14 +2,12 @@ package dns
import (
"crypto"
"crypto/dsa"
"crypto/ecdsa"
"crypto/ed25519"
"crypto/elliptic"
"crypto/rand"
"crypto/rsa"
"math/big"
"golang.org/x/crypto/ed25519"
)
// Generate generates a DNSKEY of the given bit size.
......@@ -20,11 +18,7 @@ import (
// bits should be set to the size of the algorithm.
func (k *DNSKEY) Generate(bits int) (crypto.PrivateKey, error) {
switch k.Algorithm {
case DSA, DSANSEC3SHA1:
if bits != 1024 {
return nil, ErrKeySize
}
case RSAMD5, RSASHA1, RSASHA256, RSASHA1NSEC3SHA1:
case RSASHA1, RSASHA256, RSASHA1NSEC3SHA1:
if bits < 512 || bits > 4096 {
return nil, ErrKeySize
}
......@@ -44,23 +38,12 @@ func (k *DNSKEY) Generate(bits int) (crypto.PrivateKey, error) {
if bits != 256 {
return nil, ErrKeySize
}
default:
return nil, ErrAlg
}
switch k.Algorithm {
case DSA, DSANSEC3SHA1:
params := new(dsa.Parameters)
if err := dsa.GenerateParameters(params, rand.Reader, dsa.L1024N160); err != nil {
return nil, err
}
priv := new(dsa.PrivateKey)
priv.PublicKey.Parameters = *params
err := dsa.GenerateKey(priv, rand.Reader)
if err != nil {
return nil, err
}
k.setPublicKeyDSA(params.Q, params.P, params.G, priv.PublicKey.Y)
return priv, nil
case RSAMD5, RSASHA1, RSASHA256, RSASHA512, RSASHA1NSEC3SHA1:
case RSASHA1, RSASHA256, RSASHA512, RSASHA1NSEC3SHA1:
priv, err := rsa.GenerateKey(rand.Reader, bits)
if err != nil {
return nil, err
......@@ -120,16 +103,6 @@ func (k *DNSKEY) setPublicKeyECDSA(_X, _Y *big.Int) bool {
return true
}
// Set the public key for DSA
func (k *DNSKEY) setPublicKeyDSA(_Q, _P, _G, _Y *big.Int) bool {
if _Q == nil || _P == nil || _G == nil || _Y == nil {
return false
}
buf := dsaToBuf(_Q, _P, _G, _Y)
k.PublicKey = toBase64(buf)
return true
}
// Set the public key for Ed25519
func (k *DNSKEY) setPublicKeyED25519(_K ed25519.PublicKey) bool {
if _K == nil {
......@@ -164,15 +137,3 @@ func curveToBuf(_X, _Y *big.Int, intlen int) []byte {
buf = append(buf, intToBytes(_Y, intlen)...)
return buf
}
// Set the public key for X and Y for Curve. The two
// values are just concatenated.
func dsaToBuf(_Q, _P, _G, _Y *big.Int) []byte {
t := divRoundUp(divRoundUp(_G.BitLen(), 8)-64, 8)
buf := []byte{byte(t)}
buf = append(buf, intToBytes(_Q, 20)...)
buf = append(buf, intToBytes(_P, 64+t*8)...)
buf = append(buf, intToBytes(_G, 64+t*8)...)
buf = append(buf, intToBytes(_Y, 64+t*8)...)
return buf
}
package dns
import (
"bufio"
"crypto"
"crypto/dsa"
"crypto/ecdsa"
"crypto/ed25519"
"crypto/rsa"
"io"
"math/big"
"strconv"
"strings"
"golang.org/x/crypto/ed25519"
)
// NewPrivateKey returns a PrivateKey by parsing the string s.
......@@ -43,26 +42,7 @@ func (k *DNSKEY) ReadPrivateKey(q io.Reader, file string) (crypto.PrivateKey, er
return nil, ErrPrivKey
}
switch uint8(algo) {
case DSA:
priv, err := readPrivateKeyDSA(m)
if err != nil {
return nil, err
}
pub := k.publicKeyDSA()
if pub == nil {
return nil, ErrKey
}
priv.PublicKey = *pub
return priv, nil
case RSAMD5:
fallthrough
case RSASHA1:
fallthrough
case RSASHA1NSEC3SHA1:
fallthrough
case RSASHA256:
fallthrough
case RSASHA512:
case RSASHA1, RSASHA1NSEC3SHA1, RSASHA256, RSASHA512:
priv, err := readPrivateKeyRSA(m)
if err != nil {
return nil, err
......@@ -73,11 +53,7 @@ func (k *DNSKEY) ReadPrivateKey(q io.Reader, file string) (crypto.PrivateKey, er
}
priv.PublicKey = *pub
return priv, nil
case ECCGOST:
return nil, ErrPrivKey
case ECDSAP256SHA256:
fallthrough
case ECDSAP384SHA384:
case ECDSAP256SHA256, ECDSAP384SHA384:
priv, err := readPrivateKeyECDSA(m)
if err != nil {
return nil, err
......@@ -91,7 +67,7 @@ func (k *DNSKEY) ReadPrivateKey(q io.Reader, file string) (crypto.PrivateKey, er
case ED25519:
return readPrivateKeyED25519(m)
default:
return nil, ErrPrivKey
return nil, ErrAlg
}
}
......@@ -108,21 +84,16 @@ func readPrivateKeyRSA(m map[string]string) (*rsa.PrivateKey, error) {
}
switch k {
case "modulus":
p.PublicKey.N = big.NewInt(0)
p.PublicKey.N.SetBytes(v1)
p.PublicKey.N = new(big.Int).SetBytes(v1)
case "publicexponent":
i := big.NewInt(0)
i.SetBytes(v1)
i := new(big.Int).SetBytes(v1)
p.PublicKey.E = int(i.Int64()) // int64 should be large enough
case "privateexponent":
p.D = big.NewInt(0)
p.D.SetBytes(v1)
p.D = new(big.Int).SetBytes(v1)
case "prime1":
p.Primes[0] = big.NewInt(0)
p.Primes[0].SetBytes(v1)
p.Primes[0] = new(big.Int).SetBytes(v1)
case "prime2":
p.Primes[1] = big.NewInt(0)
p.Primes[1].SetBytes(v1)
p.Primes[1] = new(big.Int).SetBytes(v1)
}
case "exponent1", "exponent2", "coefficient":
// not used in Go (yet)
......@@ -133,27 +104,9 @@ func readPrivateKeyRSA(m map[string]string) (*rsa.PrivateKey, error) {
return p, nil
}
func readPrivateKeyDSA(m map[string]string) (*dsa.PrivateKey, error) {
p := new(dsa.PrivateKey)
p.X = big.NewInt(0)
for k, v := range m {
switch k {
case "private_value(x)":
v1, err := fromBase64([]byte(v))
if err != nil {
return nil, err
}
p.X.SetBytes(v1)
case "created", "publish", "activate":
/* not used in Go (yet) */
}
}
return p, nil
}
func readPrivateKeyECDSA(m map[string]string) (*ecdsa.PrivateKey, error) {
p := new(ecdsa.PrivateKey)
p.D = big.NewInt(0)
p.D = new(big.Int)
// TODO: validate that the required flags are present
for k, v := range m {
switch k {
......@@ -194,23 +147,12 @@ func readPrivateKeyED25519(m map[string]string) (ed25519.PrivateKey, error) {
// parseKey reads a private key from r. It returns a map[string]string,
// with the key-value pairs, or an error when the file is not correct.
func parseKey(r io.Reader, file string) (map[string]string, error) {
s, cancel := scanInit(r)
m := make(map[string]string)
c := make(chan lex)
k := ""
defer func() {
cancel()
// zlexer can send up to two tokens, the next one and possibly 1 remainders.
// Do a non-blocking read.
_, ok := <-c
_, ok = <-c
if !ok {
// too bad
}
}()
// Start the lexer
go klexer(s, c)
for l := range c {
var k string
c := newKLexer(r)
for l, ok := c.Next(); ok; l, ok = c.Next() {
// It should alternate
switch l.value {
case zKey:
......@@ -219,41 +161,111 @@ func parseKey(r io.Reader, file string) (map[string]string, error) {
if k == "" {
return nil, &ParseError{file, "no private key seen", l}
}
//println("Setting", strings.ToLower(k), "to", l.token, "b")
m[strings.ToLower(k)] = l.token
k = ""
}
}
// Surface any read errors from r.
if err := c.Err(); err != nil {
return nil, &ParseError{file: file, err: err.Error()}
}
return m, nil
}
// klexer scans the sourcefile and returns tokens on the channel c.
func klexer(s *scan, c chan lex) {
var l lex
str := "" // Hold the current read text
commt := false
key := true
x, err := s.tokenText()
defer close(c)
for err == nil {
l.column = s.position.Column
l.line = s.position.Line
type klexer struct {
br io.ByteReader
readErr error
line int
column int
key bool
eol bool // end-of-line
}
func newKLexer(r io.Reader) *klexer {
br, ok := r.(io.ByteReader)
if !ok {
br = bufio.NewReaderSize(r, 1024)
}
return &klexer{
br: br,
line: 1,
key: true,
}
}
func (kl *klexer) Err() error {
if kl.readErr == io.EOF {
return nil
}
return kl.readErr
}
// readByte returns the next byte from the input
func (kl *klexer) readByte() (byte, bool) {
if kl.readErr != nil {
return 0, false
}
c, err := kl.br.ReadByte()
if err != nil {
kl.readErr = err
return 0, false
}
// delay the newline handling until the next token is delivered,
// fixes off-by-one errors when reporting a parse error.
if kl.eol {
kl.line++
kl.column = 0
kl.eol = false
}
if c == '\n' {
kl.eol = true
} else {
kl.column++
}
return c, true
}
func (kl *klexer) Next() (lex, bool) {
var (
l lex
str strings.Builder
commt bool
)
for x, ok := kl.readByte(); ok; x, ok = kl.readByte() {
l.line, l.column = kl.line, kl.column
switch x {
case ':':
if commt {
if commt || !kl.key {
break
}
l.token = str
if key {
l.value = zKey
c <- l
// Next token is a space, eat it
s.tokenText()
key = false
str = ""
} else {
l.value = zValue
}
kl.key = false
// Next token is a space, eat it
kl.readByte()
l.value = zKey
l.token = str.String()
return l, true
case ';':
commt = true
case '\n':
......@@ -261,24 +273,37 @@ func klexer(s *scan, c chan lex) {
// Reset a comment
commt = false
}
if kl.key && str.Len() == 0 {
// ignore empty lines
break
}
kl.key = true
l.value = zValue
l.token = str
c <- l
str = ""
commt = false
key = true
l.token = str.String()
return l, true
default:
if commt {
break
}
str += string(x)
str.WriteByte(x)
}
x, err = s.tokenText()
}
if len(str) > 0 {
if kl.readErr != nil && kl.readErr != io.EOF {
// Don't return any tokens after a read error occurs.
return lex{value: zEOF}, false
}
if str.Len() > 0 {
// Send remainder
l.token = str
l.value = zValue
c <- l
l.token = str.String()
return l, true
}
return lex{value: zEOF}, false
}
......@@ -2,21 +2,21 @@ package dns
import (
"crypto"
"crypto/dsa"
"crypto/ecdsa"
"crypto/ed25519"
"crypto/rsa"
"math/big"
"strconv"
"golang.org/x/crypto/ed25519"
)
const format = "Private-key-format: v1.3\n"
var bigIntOne = big.NewInt(1)
// PrivateKeyString converts a PrivateKey to a string. This string has the same
// format as the private-key-file of BIND9 (Private-key-format: v1.3).
// It needs some info from the key (the algorithm), so its a method of the DNSKEY
// It supports rsa.PrivateKey, ecdsa.PrivateKey and dsa.PrivateKey
// It needs some info from the key (the algorithm), so its a method of the DNSKEY.
// It supports *rsa.PrivateKey, *ecdsa.PrivateKey and ed25519.PrivateKey.
func (r *DNSKEY) PrivateKeyString(p crypto.PrivateKey) string {
algorithm := strconv.Itoa(int(r.Algorithm))
algorithm += " (" + AlgorithmToString[r.Algorithm] + ")"
......@@ -31,12 +31,11 @@ func (r *DNSKEY) PrivateKeyString(p crypto.PrivateKey) string {
prime2 := toBase64(p.Primes[1].Bytes())
// Calculate Exponent1/2 and Coefficient as per: http://en.wikipedia.org/wiki/RSA#Using_the_Chinese_remainder_algorithm
// and from: http://code.google.com/p/go/issues/detail?id=987
one := big.NewInt(1)
p1 := big.NewInt(0).Sub(p.Primes[0], one)
q1 := big.NewInt(0).Sub(p.Primes[1], one)
exp1 := big.NewInt(0).Mod(p.D, p1)
exp2 := big.NewInt(0).Mod(p.D, q1)
coeff := big.NewInt(0).ModInverse(p.Primes[1], p.Primes[0])
p1 := new(big.Int).Sub(p.Primes[0], bigIntOne)
q1 := new(big.Int).Sub(p.Primes[1], bigIntOne)
exp1 := new(big.Int).Mod(p.D, p1)
exp2 := new(big.Int).Mod(p.D, q1)
coeff := new(big.Int).ModInverse(p.Primes[1], p.Primes[0])
exponent1 := toBase64(exp1.Bytes())
exponent2 := toBase64(exp2.Bytes())
......@@ -66,21 +65,6 @@ func (r *DNSKEY) PrivateKeyString(p crypto.PrivateKey) string {
"Algorithm: " + algorithm + "\n" +
"PrivateKey: " + private + "\n"
case *dsa.PrivateKey:
T := divRoundUp(divRoundUp(p.PublicKey.Parameters.G.BitLen(), 8)-64, 8)
prime := toBase64(intToBytes(p.PublicKey.Parameters.P, 64+T*8))
subprime := toBase64(intToBytes(p.PublicKey.Parameters.Q, 20))
base := toBase64(intToBytes(p.PublicKey.Parameters.G, 64+T*8))
priv := toBase64(intToBytes(p.X, 20))
pub := toBase64(intToBytes(p.PublicKey.Y, 64+T*8))
return format +
"Algorithm: " + algorithm + "\n" +
"Prime(p): " + prime + "\n" +
"Subprime(q): " + subprime + "\n" +
"Base(g): " + base + "\n" +
"Private_value(x): " + priv + "\n" +
"Public_value(y): " + pub + "\n"
case ed25519.PrivateKey:
private := toBase64(p.Seed())
return format +
......
/*
Package dns implements a full featured interface to the Domain Name System.
Server- and client-side programming is supported.
The package allows complete control over what is sent out to the DNS. The package
API follows the less-is-more principle, by presenting a small, clean interface.
Both server- and client-side programming is supported. The package allows
complete control over what is sent out to the DNS. The API follows the
less-is-more principle, by presenting a small, clean interface.
The package dns supports (asynchronous) querying/replying, incoming/outgoing zone transfers,
It supports (asynchronous) querying/replying, incoming/outgoing zone transfers,
TSIG, EDNS0, dynamic updates, notifies and DNSSEC validation/signing.
Note that domain names MUST be fully qualified, before sending them, unqualified
Note that domain names MUST be fully qualified before sending them, unqualified
names in a message will result in a packing failure.
Resource records are native types. They are not stored in wire format.
Basic usage pattern for creating a new resource record:
Resource records are native types. They are not stored in wire format. Basic
usage pattern for creating a new resource record:
r := new(dns.MX)
r.Hdr = dns.RR_Header{Name: "miek.nl.", Rrtype: dns.TypeMX,
Class: dns.ClassINET, Ttl: 3600}
r.Hdr = dns.RR_Header{Name: "miek.nl.", Rrtype: dns.TypeMX, Class: dns.ClassINET, Ttl: 3600}
r.Preference = 10
r.Mx = "mx.miek.nl."
......@@ -30,8 +30,8 @@ Or even:
mx, err := dns.NewRR("$ORIGIN nl.\nmiek 1H IN MX 10 mx.miek")
In the DNS messages are exchanged, these messages contain resource
records (sets). Use pattern for creating a message:
In the DNS messages are exchanged, these messages contain resource records
(sets). Use pattern for creating a message:
m := new(dns.Msg)
m.SetQuestion("miek.nl.", dns.TypeMX)
......@@ -40,8 +40,8 @@ Or when not certain if the domain name is fully qualified:
m.SetQuestion(dns.Fqdn("miek.nl"), dns.TypeMX)
The message m is now a message with the question section set to ask
the MX records for the miek.nl. zone.
The message m is now a message with the question section set to ask the MX
records for the miek.nl. zone.
The following is slightly more verbose, but more flexible:
......@@ -51,9 +51,8 @@ The following is slightly more verbose, but more flexible:
m1.Question = make([]dns.Question, 1)
m1.Question[0] = dns.Question{"miek.nl.", dns.TypeMX, dns.ClassINET}
After creating a message it can be sent.
Basic use pattern for synchronous querying the DNS at a
server configured on 127.0.0.1 and port 53:
After creating a message it can be sent. Basic use pattern for synchronous
querying the DNS at a server configured on 127.0.0.1 and port 53:
c := new(dns.Client)
in, rtt, err := c.Exchange(m1, "127.0.0.1:53")
......@@ -84,7 +83,7 @@ with:
in, err := dns.Exchange(m1, "127.0.0.1:53")
When this functions returns you will get dns message. A dns message consists
When this functions returns you will get DNS message. A DNS message consists
out of four sections.
The question section: in.Question, the answer section: in.Answer,
the authority section: in.Ns and the additional section: in.Extra.
......@@ -99,25 +98,24 @@ the Answer section:
Domain Name and TXT Character String Representations
Both domain names and TXT character strings are converted to presentation
form both when unpacked and when converted to strings.
Both domain names and TXT character strings are converted to presentation form
both when unpacked and when converted to strings.
For TXT character strings, tabs, carriage returns and line feeds will be
converted to \t, \r and \n respectively. Back slashes and quotations marks
will be escaped. Bytes below 32 and above 127 will be converted to \DDD
form.
converted to \t, \r and \n respectively. Back slashes and quotations marks will
be escaped. Bytes below 32 and above 127 will be converted to \DDD form.
For domain names, in addition to the above rules brackets, periods,
spaces, semicolons and the at symbol are escaped.
For domain names, in addition to the above rules brackets, periods, spaces,
semicolons and the at symbol are escaped.
DNSSEC
DNSSEC (DNS Security Extension) adds a layer of security to the DNS. It
uses public key cryptography to sign resource records. The
public keys are stored in DNSKEY records and the signatures in RRSIG records.
DNSSEC (DNS Security Extension) adds a layer of security to the DNS. It uses
public key cryptography to sign resource records. The public keys are stored in
DNSKEY records and the signatures in RRSIG records.
Requesting DNSSEC information for a zone is done by adding the DO (DNSSEC OK) bit
to a request.
Requesting DNSSEC information for a zone is done by adding the DO (DNSSEC OK)
bit to a request.
m := new(dns.Msg)
m.SetEdns0(4096, true)
......@@ -126,9 +124,9 @@ Signature generation, signature verification and key generation are all supporte
DYNAMIC UPDATES
Dynamic updates reuses the DNS message format, but renames three of
the sections. Question is Zone, Answer is Prerequisite, Authority is
Update, only the Additional is not renamed. See RFC 2136 for the gory details.
Dynamic updates reuses the DNS message format, but renames three of the
sections. Question is Zone, Answer is Prerequisite, Authority is Update, only
the Additional is not renamed. See RFC 2136 for the gory details.
You can set a rather complex set of rules for the existence of absence of
certain resource records or names in a zone to specify if resource records
......@@ -145,10 +143,9 @@ DNS function shows which functions exist to specify the prerequisites.
NONE rrset empty RRset does not exist dns.RRsetNotUsed
zone rrset rr RRset exists (value dep) dns.Used
The prerequisite section can also be left empty.
If you have decided on the prerequisites you can tell what RRs should
be added or deleted. The next table shows the options you have and
what functions to call.
The prerequisite section can also be left empty. If you have decided on the
prerequisites you can tell what RRs should be added or deleted. The next table
shows the options you have and what functions to call.
3.4.2.6 - Table Of Metavalues Used In Update Section
......@@ -162,7 +159,7 @@ what functions to call.
TRANSACTION SIGNATURE
An TSIG or transaction signature adds a HMAC TSIG record to each message sent.
The supported algorithms include: HmacMD5, HmacSHA1, HmacSHA256 and HmacSHA512.
The supported algorithms include: HmacSHA1, HmacSHA256 and HmacSHA512.
Basic use pattern when querying with a TSIG name "axfr." (note that these key names
must be fully qualified - as they are domain names) and the base64 secret
......@@ -177,25 +174,49 @@ changes to the RRset after calling SetTsig() the signature will be incorrect.
c.TsigSecret = map[string]string{"axfr.": "so6ZGir4GPAqINNh9U5c3A=="}
m := new(dns.Msg)
m.SetQuestion("miek.nl.", dns.TypeMX)
m.SetTsig("axfr.", dns.HmacMD5, 300, time.Now().Unix())
m.SetTsig("axfr.", dns.HmacSHA256, 300, time.Now().Unix())
...
// When sending the TSIG RR is calculated and filled in before sending
When requesting an zone transfer (almost all TSIG usage is when requesting zone transfers), with
TSIG, this is the basic use pattern. In this example we request an AXFR for
miek.nl. with TSIG key named "axfr." and secret "so6ZGir4GPAqINNh9U5c3A=="
and using the server 176.58.119.54:
When requesting an zone transfer (almost all TSIG usage is when requesting zone
transfers), with TSIG, this is the basic use pattern. In this example we
request an AXFR for miek.nl. with TSIG key named "axfr." and secret
"so6ZGir4GPAqINNh9U5c3A==" and using the server 176.58.119.54:
t := new(dns.Transfer)
m := new(dns.Msg)
t.TsigSecret = map[string]string{"axfr.": "so6ZGir4GPAqINNh9U5c3A=="}
m.SetAxfr("miek.nl.")
m.SetTsig("axfr.", dns.HmacMD5, 300, time.Now().Unix())
m.SetTsig("axfr.", dns.HmacSHA256, 300, time.Now().Unix())
c, err := t.In(m, "176.58.119.54:53")
for r := range c { ... }
You can now read the records from the transfer as they come in. Each envelope is checked with TSIG.
If something is not correct an error is returned.
You can now read the records from the transfer as they come in. Each envelope
is checked with TSIG. If something is not correct an error is returned.
A custom TSIG implementation can be used. This requires additional code to
perform any session establishment and signature generation/verification. The
client must be configured with an implementation of the TsigProvider interface:
type Provider struct{}
func (*Provider) Generate(msg []byte, tsig *dns.TSIG) ([]byte, error) {
// Use tsig.Hdr.Name and tsig.Algorithm in your code to
// generate the MAC using msg as the payload.
}
func (*Provider) Verify(msg []byte, tsig *dns.TSIG) error {
// Use tsig.Hdr.Name and tsig.Algorithm in your code to verify
// that msg matches the value in tsig.MAC.
}
c := new(dns.Client)
c.TsigProvider = new(Provider)
m := new(dns.Msg)
m.SetQuestion("miek.nl.", dns.TypeMX)
m.SetTsig(keyname, dns.HmacSHA256, 300, time.Now().Unix())
...
// TSIG RR is calculated by calling your Generate method
Basic use pattern validating and replying to a message that has TSIG set.
......@@ -210,9 +231,9 @@ Basic use pattern validating and replying to a message that has TSIG set.
if r.IsTsig() != nil {
if w.TsigStatus() == nil {
// *Msg r has an TSIG record and it was validated
m.SetTsig("axfr.", dns.HmacMD5, 300, time.Now().Unix())
m.SetTsig("axfr.", dns.HmacSHA256, 300, time.Now().Unix())
} else {
// *Msg r has an TSIG records and it was not valided
// *Msg r has an TSIG records and it was not validated
}
}
w.WriteMsg(m)
......@@ -220,28 +241,28 @@ Basic use pattern validating and replying to a message that has TSIG set.
PRIVATE RRS
RFC 6895 sets aside a range of type codes for private use. This range
is 65,280 - 65,534 (0xFF00 - 0xFFFE). When experimenting with new Resource Records these
RFC 6895 sets aside a range of type codes for private use. This range is 65,280
- 65,534 (0xFF00 - 0xFFFE). When experimenting with new Resource Records these
can be used, before requesting an official type code from IANA.
see http://miek.nl/2014/September/21/idn-and-private-rr-in-go-dns/ for more
See https://miek.nl/2014/september/21/idn-and-private-rr-in-go-dns/ for more
information.
EDNS0
EDNS0 is an extension mechanism for the DNS defined in RFC 2671 and updated
by RFC 6891. It defines an new RR type, the OPT RR, which is then completely
EDNS0 is an extension mechanism for the DNS defined in RFC 2671 and updated by
RFC 6891. It defines a new RR type, the OPT RR, which is then completely
abused.
Basic use pattern for creating an (empty) OPT RR:
o := new(dns.OPT)
o.Hdr.Name = "." // MUST be the root zone, per definition.
o.Hdr.Rrtype = dns.TypeOPT
The rdata of an OPT RR consists out of a slice of EDNS0 (RFC 6891)
interfaces. Currently only a few have been standardized: EDNS0_NSID
(RFC 5001) and EDNS0_SUBNET (draft-vandergaast-edns-client-subnet-02). Note
that these options may be combined in an OPT RR.
The rdata of an OPT RR consists out of a slice of EDNS0 (RFC 6891) interfaces.
Currently only a few have been standardized: EDNS0_NSID (RFC 5001) and
EDNS0_SUBNET (RFC 7871). Note that these options may be combined in an OPT RR.
Basic use pattern for a server to check if (and which) options are set:
// o is a dns.OPT
......@@ -262,10 +283,9 @@ From RFC 2931:
... protection for glue records, DNS requests, protection for message headers
on requests and responses, and protection of the overall integrity of a response.
It works like TSIG, except that SIG(0) uses public key cryptography, instead of the shared
secret approach in TSIG.
Supported algorithms: DSA, ECDSAP256SHA256, ECDSAP384SHA384, RSASHA1, RSASHA256 and
RSASHA512.
It works like TSIG, except that SIG(0) uses public key cryptography, instead of
the shared secret approach in TSIG. Supported algorithms: ECDSAP256SHA256,
ECDSAP384SHA384, RSASHA1, RSASHA256 and RSASHA512.
Signing subsequent messages in multi-message sessions is not implemented.
*/
......
......@@ -3,23 +3,35 @@ package dns
//go:generate go run duplicate_generate.go
// IsDuplicate checks of r1 and r2 are duplicates of each other, excluding the TTL.
// So this means the header data is equal *and* the RDATA is the same. Return true
// is so, otherwise false.
// It's is a protocol violation to have identical RRs in a message.
// So this means the header data is equal *and* the RDATA is the same. Returns true
// if so, otherwise false. It's a protocol violation to have identical RRs in a message.
func IsDuplicate(r1, r2 RR) bool {
if r1.Header().Class != r2.Header().Class {
// Check whether the record header is identical.
if !r1.Header().isDuplicate(r2.Header()) {
return false
}
if r1.Header().Rrtype != r2.Header().Rrtype {
// Check whether the RDATA is identical.
return r1.isDuplicate(r2)
}
func (r1 *RR_Header) isDuplicate(_r2 RR) bool {
r2, ok := _r2.(*RR_Header)
if !ok {
return false
}
if r1.Class != r2.Class {
return false
}
if r1.Rrtype != r2.Rrtype {
return false
}
if !isDulicateName(r1.Header().Name, r2.Header().Name) {
if !isDuplicateName(r1.Name, r2.Name) {
return false
}
// ignore TTL
return isDuplicateRdata(r1, r2)
return true
}
// isDulicateName checks if the domain names s1 and s2 are equal.
func isDulicateName(s1, s2 string) bool { return equal(s1, s2) }
// isDuplicateName checks if the domain names s1 and s2 are equal.
func isDuplicateName(s1, s2 string) bool { return equal(s1, s2) }
//+build ignore
// types_generate.go is meant to run with go generate. It will use
// go/{importer,types} to track down all the RR struct types. Then for each type
// it will generate conversion tables (TypeToRR and TypeToString) and banal
// methods (len, Header, copy) based on the struct tags. The generated source is
// written to ztypes.go, and is meant to be checked into git.
package main
import (
"bytes"
"fmt"
"go/format"
"go/importer"
"go/types"
"log"
"os"
)
var packageHdr = `
// Code generated by "go run duplicate_generate.go"; DO NOT EDIT.
package dns
`
func getTypeStruct(t types.Type, scope *types.Scope) (*types.Struct, bool) {
st, ok := t.Underlying().(*types.Struct)
if !ok {
return nil, false
}
if st.Field(0).Type() == scope.Lookup("RR_Header").Type() {
return st, false
}
if st.Field(0).Anonymous() {
st, _ := getTypeStruct(st.Field(0).Type(), scope)
return st, true
}
return nil, false
}
func main() {
// Import and type-check the package
pkg, err := importer.Default().Import("github.com/miekg/dns")
fatalIfErr(err)
scope := pkg.Scope()
// Collect actual types (*X)
var namedTypes []string
for _, name := range scope.Names() {
o := scope.Lookup(name)
if o == nil || !o.Exported() {
continue
}
if st, _ := getTypeStruct(o.Type(), scope); st == nil {
continue
}
if name == "PrivateRR" || name == "RFC3597" {
continue
}
if name == "OPT" || name == "ANY" || name == "IXFR" || name == "AXFR" {
continue
}
namedTypes = append(namedTypes, o.Name())
}
b := &bytes.Buffer{}
b.WriteString(packageHdr)
// Generate the giant switch that calls the correct function for each type.
fmt.Fprint(b, "// isDuplicateRdata calls the rdata specific functions\n")
fmt.Fprint(b, "func isDuplicateRdata(r1, r2 RR) bool {\n")
fmt.Fprint(b, "switch r1.Header().Rrtype {\n")
for _, name := range namedTypes {
o := scope.Lookup(name)
_, isEmbedded := getTypeStruct(o.Type(), scope)
if isEmbedded {
continue
}
fmt.Fprintf(b, "case Type%s:\nreturn isDuplicate%s(r1.(*%s), r2.(*%s))\n", name, name, name, name)
}
fmt.Fprintf(b, "}\nreturn false\n}\n")
// Generate the duplicate check for each type.
fmt.Fprint(b, "// isDuplicate() functions\n\n")
for _, name := range namedTypes {
o := scope.Lookup(name)
st, isEmbedded := getTypeStruct(o.Type(), scope)
if isEmbedded {
continue
}
fmt.Fprintf(b, "func isDuplicate%s(r1, r2 *%s) bool {\n", name, name)
for i := 1; i < st.NumFields(); i++ {
field := st.Field(i).Name()
o2 := func(s string) { fmt.Fprintf(b, s+"\n", field, field) }
o3 := func(s string) { fmt.Fprintf(b, s+"\n", field, field, field) }
// For some reason, a and aaaa don't pop up as *types.Slice here (mostly like because the are
// *indirectly* defined as a slice in the net package).
if _, ok := st.Field(i).Type().(*types.Slice); ok || st.Tag(i) == `dns:"a"` || st.Tag(i) == `dns:"aaaa"` {
o2("if len(r1.%s) != len(r2.%s) {\nreturn false\n}")
if st.Tag(i) == `dns:"cdomain-name"` || st.Tag(i) == `dns:"domain-name"` {
o3(`for i := 0; i < len(r1.%s); i++ {
if !isDulicateName(r1.%s[i], r2.%s[i]) {
return false
}
}`)
continue
}
o3(`for i := 0; i < len(r1.%s); i++ {
if r1.%s[i] != r2.%s[i] {
return false
}
}`)
continue
}
switch st.Tag(i) {
case `dns:"-"`:
// ignored
case `dns:"cdomain-name"`, `dns:"domain-name"`:
o2("if !isDulicateName(r1.%s, r2.%s) {\nreturn false\n}")
default:
o2("if r1.%s != r2.%s {\nreturn false\n}")
}
}
fmt.Fprintf(b, "return true\n}\n\n")
}
// gofmt
res, err := format.Source(b.Bytes())
if err != nil {
b.WriteTo(os.Stderr)
log.Fatal(err)
}
// write result
f, err := os.Create("zduplicate.go")
fatalIfErr(err)
defer f.Close()
f.Write(res)
}
func fatalIfErr(err error) {
if err != nil {
log.Fatal(err)
}
}
......@@ -14,6 +14,7 @@ const (
EDNS0LLQ = 0x1 // long lived queries: http://tools.ietf.org/html/draft-sekar-dns-llq-01
EDNS0UL = 0x2 // update lease draft: http://files.dns-sd.org/draft-sekar-dns-ul.txt
EDNS0NSID = 0x3 // nsid (See RFC 5001)
EDNS0ESU = 0x4 // ENUM Source-URI draft: https://datatracker.ietf.org/doc/html/draft-kaplan-enum-source-uri-00
EDNS0DAU = 0x5 // DNSSEC Algorithm Understood
EDNS0DHU = 0x6 // DS Hash Understood
EDNS0N3U = 0x7 // NSEC3 Hash Understood
......@@ -22,11 +23,49 @@ const (
EDNS0COOKIE = 0xa // EDNS0 Cookie
EDNS0TCPKEEPALIVE = 0xb // EDNS0 tcp keep alive (See RFC 7828)
EDNS0PADDING = 0xc // EDNS0 padding (See RFC 7830)
EDNS0EDE = 0xf // EDNS0 extended DNS errors (See RFC 8914)
EDNS0LOCALSTART = 0xFDE9 // Beginning of range reserved for local/experimental use (See RFC 6891)
EDNS0LOCALEND = 0xFFFE // End of range reserved for local/experimental use (See RFC 6891)
_DO = 1 << 15 // DNSSEC OK
)
// makeDataOpt is used to unpack the EDNS0 option(s) from a message.
func makeDataOpt(code uint16) EDNS0 {
// All the EDNS0.* constants above need to be in this switch.
switch code {
case EDNS0LLQ:
return new(EDNS0_LLQ)
case EDNS0UL:
return new(EDNS0_UL)
case EDNS0NSID:
return new(EDNS0_NSID)
case EDNS0DAU:
return new(EDNS0_DAU)
case EDNS0DHU:
return new(EDNS0_DHU)
case EDNS0N3U:
return new(EDNS0_N3U)
case EDNS0SUBNET:
return new(EDNS0_SUBNET)
case EDNS0EXPIRE:
return new(EDNS0_EXPIRE)
case EDNS0COOKIE:
return new(EDNS0_COOKIE)
case EDNS0TCPKEEPALIVE:
return new(EDNS0_TCP_KEEPALIVE)
case EDNS0PADDING:
return new(EDNS0_PADDING)
case EDNS0EDE:
return new(EDNS0_EDE)
case EDNS0ESU:
return &EDNS0_ESU{Code: EDNS0ESU}
default:
e := new(EDNS0_LOCAL)
e.Code = code
return e
}
}
// OPT is the EDNS0 RR appended to messages to convey extra (meta) information.
// See RFC 6891.
type OPT struct {
......@@ -59,6 +98,8 @@ func (rr *OPT) String() string {
s += "\n; SUBNET: " + o.String()
case *EDNS0_COOKIE:
s += "\n; COOKIE: " + o.String()
case *EDNS0_TCP_KEEPALIVE:
s += "\n; KEEPALIVE: " + o.String()
case *EDNS0_UL:
s += "\n; UPDATE LEASE: " + o.String()
case *EDNS0_LLQ:
......@@ -73,21 +114,31 @@ func (rr *OPT) String() string {
s += "\n; LOCAL OPT: " + o.String()
case *EDNS0_PADDING:
s += "\n; PADDING: " + o.String()
case *EDNS0_EDE:
s += "\n; EDE: " + o.String()
case *EDNS0_ESU:
s += "\n; ESU: " + o.String()
}
}
return s
}
func (rr *OPT) len() int {
l := rr.Hdr.len()
for i := 0; i < len(rr.Option); i++ {
func (rr *OPT) len(off int, compression map[string]struct{}) int {
l := rr.Hdr.len(off, compression)
for _, o := range rr.Option {
l += 4 // Account for 2-byte option code and 2-byte option length.
lo, _ := rr.Option[i].pack()
lo, _ := o.pack()
l += len(lo)
}
return l
}
func (*OPT) parse(c *zlexer, origin string) *ParseError {
return &ParseError{err: "OPT records do not have a presentation format"}
}
func (rr *OPT) isDuplicate(r2 RR) bool { return false }
// return the old value -> delete SetVersion?
// Version returns the EDNS version used. Only zero is defined.
......@@ -102,15 +153,14 @@ func (rr *OPT) SetVersion(v uint8) {
// ExtendedRcode returns the EDNS extended RCODE field (the upper 8 bits of the TTL).
func (rr *OPT) ExtendedRcode() int {
return int(rr.Hdr.Ttl&0xFF000000>>24) + 15
return int(rr.Hdr.Ttl&0xFF000000>>24) << 4
}
// SetExtendedRcode sets the EDNS extended RCODE field.
func (rr *OPT) SetExtendedRcode(v uint8) {
if v < RcodeBadVers { // Smaller than 16.. Use the 4 bits you have!
return
}
rr.Hdr.Ttl = rr.Hdr.Ttl&0x00FFFFFF | uint32(v-15)<<24
//
// If the RCODE is not an extended RCODE, will reset the extended RCODE field to 0.
func (rr *OPT) SetExtendedRcode(v uint16) {
rr.Hdr.Ttl = rr.Hdr.Ttl&0x00FFFFFF | uint32(v>>4)<<24
}
// UDPSize returns the UDP buffer size.
......@@ -143,6 +193,16 @@ func (rr *OPT) SetDo(do ...bool) {
}
}
// Z returns the Z part of the OPT RR as a uint16 with only the 15 least significant bits used.
func (rr *OPT) Z() uint16 {
return uint16(rr.Hdr.Ttl & 0x7FFF)
}
// SetZ sets the Z part of the OPT RR, note only the 15 least significant bits of z are used.
func (rr *OPT) SetZ(z uint16) {
rr.Hdr.Ttl = rr.Hdr.Ttl&^0x7FFF | uint32(z&0x7FFF)
}
// EDNS0 defines an EDNS0 Option. An OPT RR can have multiple options appended to it.
type EDNS0 interface {
// Option returns the option code for the option.
......@@ -154,6 +214,8 @@ type EDNS0 interface {
unpack([]byte) error
// String returns the string representation of the option.
String() string
// copy returns a deep-copy of the option.
copy() EDNS0
}
// EDNS0_NSID option is used to retrieve a nameserver
......@@ -184,7 +246,8 @@ func (e *EDNS0_NSID) pack() ([]byte, error) {
// Option implements the EDNS0 interface.
func (e *EDNS0_NSID) Option() uint16 { return EDNS0NSID } // Option returns the option code.
func (e *EDNS0_NSID) unpack(b []byte) error { e.Nsid = hex.EncodeToString(b); return nil }
func (e *EDNS0_NSID) String() string { return string(e.Nsid) }
func (e *EDNS0_NSID) String() string { return e.Nsid }
func (e *EDNS0_NSID) copy() EDNS0 { return &EDNS0_NSID{e.Code, e.Nsid} }
// EDNS0_SUBNET is the subnet option that is used to give the remote nameserver
// an idea of where the client lives. See RFC 7871. It can then give back a different
......@@ -274,22 +337,16 @@ func (e *EDNS0_SUBNET) unpack(b []byte) error {
if e.SourceNetmask > net.IPv4len*8 || e.SourceScope > net.IPv4len*8 {
return errors.New("dns: bad netmask")
}
addr := make([]byte, net.IPv4len)
for i := 0; i < net.IPv4len && 4+i < len(b); i++ {
addr[i] = b[4+i]
}
e.Address = net.IPv4(addr[0], addr[1], addr[2], addr[3])
addr := make(net.IP, net.IPv4len)
copy(addr, b[4:])
e.Address = addr.To16()
case 2:
if e.SourceNetmask > net.IPv6len*8 || e.SourceScope > net.IPv6len*8 {
return errors.New("dns: bad netmask")
}
addr := make([]byte, net.IPv6len)
for i := 0; i < net.IPv6len && 4+i < len(b); i++ {
addr[i] = b[4+i]
}
e.Address = net.IP{addr[0], addr[1], addr[2], addr[3], addr[4],
addr[5], addr[6], addr[7], addr[8], addr[9], addr[10],
addr[11], addr[12], addr[13], addr[14], addr[15]}
addr := make(net.IP, net.IPv6len)
copy(addr, b[4:])
e.Address = addr
default:
return errors.New("dns: bad address family")
}
......@@ -308,6 +365,16 @@ func (e *EDNS0_SUBNET) String() (s string) {
return
}
func (e *EDNS0_SUBNET) copy() EDNS0 {
return &EDNS0_SUBNET{
e.Code,
e.Family,
e.SourceNetmask,
e.SourceScope,
e.Address,
}
}
// The EDNS0_COOKIE option is used to add a DNS Cookie to a message.
//
// o := new(dns.OPT)
......@@ -343,11 +410,12 @@ func (e *EDNS0_COOKIE) pack() ([]byte, error) {
func (e *EDNS0_COOKIE) Option() uint16 { return EDNS0COOKIE }
func (e *EDNS0_COOKIE) unpack(b []byte) error { e.Cookie = hex.EncodeToString(b); return nil }
func (e *EDNS0_COOKIE) String() string { return e.Cookie }
func (e *EDNS0_COOKIE) copy() EDNS0 { return &EDNS0_COOKIE{e.Code, e.Cookie} }
// The EDNS0_UL (Update Lease) (draft RFC) option is used to tell the server to set
// an expiration on an update RR. This is helpful for clients that cannot clean
// up after themselves. This is a draft RFC and more information can be found at
// http://files.dns-sd.org/draft-sekar-dns-ul.txt
// https://tools.ietf.org/html/draft-sekar-dns-ul-02
//
// o := new(dns.OPT)
// o.Hdr.Name = "."
......@@ -357,23 +425,36 @@ func (e *EDNS0_COOKIE) String() string { return e.Cookie }
// e.Lease = 120 // in seconds
// o.Option = append(o.Option, e)
type EDNS0_UL struct {
Code uint16 // Always EDNS0UL
Lease uint32
Code uint16 // Always EDNS0UL
Lease uint32
KeyLease uint32
}
// Option implements the EDNS0 interface.
func (e *EDNS0_UL) Option() uint16 { return EDNS0UL }
func (e *EDNS0_UL) String() string { return strconv.FormatUint(uint64(e.Lease), 10) }
func (e *EDNS0_UL) String() string { return fmt.Sprintf("%d %d", e.Lease, e.KeyLease) }
func (e *EDNS0_UL) copy() EDNS0 { return &EDNS0_UL{e.Code, e.Lease, e.KeyLease} }
// Copied: http://golang.org/src/pkg/net/dnsmsg.go
func (e *EDNS0_UL) pack() ([]byte, error) {
b := make([]byte, 4)
var b []byte
if e.KeyLease == 0 {
b = make([]byte, 4)
} else {
b = make([]byte, 8)
binary.BigEndian.PutUint32(b[4:], e.KeyLease)
}
binary.BigEndian.PutUint32(b, e.Lease)
return b, nil
}
func (e *EDNS0_UL) unpack(b []byte) error {
if len(b) < 4 {
switch len(b) {
case 4:
e.KeyLease = 0
case 8:
e.KeyLease = binary.BigEndian.Uint32(b[4:])
default:
return ErrBuf
}
e.Lease = binary.BigEndian.Uint32(b)
......@@ -418,12 +499,15 @@ func (e *EDNS0_LLQ) unpack(b []byte) error {
func (e *EDNS0_LLQ) String() string {
s := strconv.FormatUint(uint64(e.Version), 10) + " " + strconv.FormatUint(uint64(e.Opcode), 10) +
" " + strconv.FormatUint(uint64(e.Error), 10) + " " + strconv.FormatUint(uint64(e.Id), 10) +
" " + strconv.FormatUint(uint64(e.Error), 10) + " " + strconv.FormatUint(e.Id, 10) +
" " + strconv.FormatUint(uint64(e.LeaseLife), 10)
return s
}
func (e *EDNS0_LLQ) copy() EDNS0 {
return &EDNS0_LLQ{e.Code, e.Version, e.Opcode, e.Error, e.Id, e.LeaseLife}
}
// EDNS0_DUA implements the EDNS0 "DNSSEC Algorithm Understood" option. See RFC 6975.
// EDNS0_DAU implements the EDNS0 "DNSSEC Algorithm Understood" option. See RFC 6975.
type EDNS0_DAU struct {
Code uint16 // Always EDNS0DAU
AlgCode []uint8
......@@ -436,15 +520,16 @@ func (e *EDNS0_DAU) unpack(b []byte) error { e.AlgCode = b; return nil }
func (e *EDNS0_DAU) String() string {
s := ""
for i := 0; i < len(e.AlgCode); i++ {
if a, ok := AlgorithmToString[e.AlgCode[i]]; ok {
for _, alg := range e.AlgCode {
if a, ok := AlgorithmToString[alg]; ok {
s += " " + a
} else {
s += " " + strconv.Itoa(int(e.AlgCode[i]))
s += " " + strconv.Itoa(int(alg))
}
}
return s
}
func (e *EDNS0_DAU) copy() EDNS0 { return &EDNS0_DAU{e.Code, e.AlgCode} }
// EDNS0_DHU implements the EDNS0 "DS Hash Understood" option. See RFC 6975.
type EDNS0_DHU struct {
......@@ -459,15 +544,16 @@ func (e *EDNS0_DHU) unpack(b []byte) error { e.AlgCode = b; return nil }
func (e *EDNS0_DHU) String() string {
s := ""
for i := 0; i < len(e.AlgCode); i++ {
if a, ok := HashToString[e.AlgCode[i]]; ok {
for _, alg := range e.AlgCode {
if a, ok := HashToString[alg]; ok {
s += " " + a
} else {
s += " " + strconv.Itoa(int(e.AlgCode[i]))
s += " " + strconv.Itoa(int(alg))
}
}
return s
}
func (e *EDNS0_DHU) copy() EDNS0 { return &EDNS0_DHU{e.Code, e.AlgCode} }
// EDNS0_N3U implements the EDNS0 "NSEC3 Hash Understood" option. See RFC 6975.
type EDNS0_N3U struct {
......@@ -483,43 +569,58 @@ func (e *EDNS0_N3U) unpack(b []byte) error { e.AlgCode = b; return nil }
func (e *EDNS0_N3U) String() string {
// Re-use the hash map
s := ""
for i := 0; i < len(e.AlgCode); i++ {
if a, ok := HashToString[e.AlgCode[i]]; ok {
for _, alg := range e.AlgCode {
if a, ok := HashToString[alg]; ok {
s += " " + a
} else {
s += " " + strconv.Itoa(int(e.AlgCode[i]))
s += " " + strconv.Itoa(int(alg))
}
}
return s
}
func (e *EDNS0_N3U) copy() EDNS0 { return &EDNS0_N3U{e.Code, e.AlgCode} }
// EDNS0_EXPIRE implementes the EDNS0 option as described in RFC 7314.
// EDNS0_EXPIRE implements the EDNS0 option as described in RFC 7314.
type EDNS0_EXPIRE struct {
Code uint16 // Always EDNS0EXPIRE
Expire uint32
Empty bool // Empty is used to signal an empty Expire option in a backwards compatible way, it's not used on the wire.
}
// Option implements the EDNS0 interface.
func (e *EDNS0_EXPIRE) Option() uint16 { return EDNS0EXPIRE }
func (e *EDNS0_EXPIRE) String() string { return strconv.FormatUint(uint64(e.Expire), 10) }
func (e *EDNS0_EXPIRE) copy() EDNS0 { return &EDNS0_EXPIRE{e.Code, e.Expire, e.Empty} }
func (e *EDNS0_EXPIRE) pack() ([]byte, error) {
if e.Empty {
return []byte{}, nil
}
b := make([]byte, 4)
b[0] = byte(e.Expire >> 24)
b[1] = byte(e.Expire >> 16)
b[2] = byte(e.Expire >> 8)
b[3] = byte(e.Expire)
binary.BigEndian.PutUint32(b, e.Expire)
return b, nil
}
func (e *EDNS0_EXPIRE) unpack(b []byte) error {
if len(b) == 0 {
// zero-length EXPIRE query, see RFC 7314 Section 2
e.Empty = true
return nil
}
if len(b) < 4 {
return ErrBuf
}
e.Expire = binary.BigEndian.Uint32(b)
e.Empty = false
return nil
}
func (e *EDNS0_EXPIRE) String() (s string) {
if e.Empty {
return ""
}
return strconv.FormatUint(uint64(e.Expire), 10)
}
// The EDNS0_LOCAL option is used for local/experimental purposes. The option
// code is recommended to be within the range [EDNS0LOCALSTART, EDNS0LOCALEND]
// (RFC6891), although any unassigned code can actually be used. The content of
......@@ -543,6 +644,11 @@ func (e *EDNS0_LOCAL) Option() uint16 { return e.Code }
func (e *EDNS0_LOCAL) String() string {
return strconv.FormatInt(int64(e.Code), 10) + ":0x" + hex.EncodeToString(e.Data)
}
func (e *EDNS0_LOCAL) copy() EDNS0 {
b := make([]byte, len(e.Data))
copy(b, e.Data)
return &EDNS0_LOCAL{e.Code, b}
}
func (e *EDNS0_LOCAL) pack() ([]byte, error) {
b := make([]byte, len(e.Data))
......@@ -565,57 +671,53 @@ func (e *EDNS0_LOCAL) unpack(b []byte) error {
// EDNS0_TCP_KEEPALIVE is an EDNS0 option that instructs the server to keep
// the TCP connection alive. See RFC 7828.
type EDNS0_TCP_KEEPALIVE struct {
Code uint16 // Always EDNSTCPKEEPALIVE
Length uint16 // the value 0 if the TIMEOUT is omitted, the value 2 if it is present;
Timeout uint16 // an idle timeout value for the TCP connection, specified in units of 100 milliseconds, encoded in network byte order.
Code uint16 // Always EDNSTCPKEEPALIVE
// Timeout is an idle timeout value for the TCP connection, specified in
// units of 100 milliseconds, encoded in network byte order. If set to 0,
// pack will return a nil slice.
Timeout uint16
// Length is the option's length.
// Deprecated: this field is deprecated and is always equal to 0.
Length uint16
}
// Option implements the EDNS0 interface.
func (e *EDNS0_TCP_KEEPALIVE) Option() uint16 { return EDNS0TCPKEEPALIVE }
func (e *EDNS0_TCP_KEEPALIVE) pack() ([]byte, error) {
if e.Timeout != 0 && e.Length != 2 {
return nil, errors.New("dns: timeout specified but length is not 2")
}
if e.Timeout == 0 && e.Length != 0 {
return nil, errors.New("dns: timeout not specified but length is not 0")
if e.Timeout > 0 {
b := make([]byte, 2)
binary.BigEndian.PutUint16(b, e.Timeout)
return b, nil
}
b := make([]byte, 4+e.Length)
binary.BigEndian.PutUint16(b[0:], e.Code)
binary.BigEndian.PutUint16(b[2:], e.Length)
if e.Length == 2 {
binary.BigEndian.PutUint16(b[4:], e.Timeout)
}
return b, nil
return nil, nil
}
func (e *EDNS0_TCP_KEEPALIVE) unpack(b []byte) error {
if len(b) < 4 {
return ErrBuf
}
e.Length = binary.BigEndian.Uint16(b[2:4])
if e.Length != 0 && e.Length != 2 {
return errors.New("dns: length mismatch, want 0/2 but got " + strconv.FormatUint(uint64(e.Length), 10))
}
if e.Length == 2 {
if len(b) < 6 {
return ErrBuf
}
e.Timeout = binary.BigEndian.Uint16(b[4:6])
switch len(b) {
case 0:
case 2:
e.Timeout = binary.BigEndian.Uint16(b)
default:
return fmt.Errorf("dns: length mismatch, want 0/2 but got %d", len(b))
}
return nil
}
func (e *EDNS0_TCP_KEEPALIVE) String() (s string) {
s = "use tcp keep-alive"
if e.Length == 0 {
func (e *EDNS0_TCP_KEEPALIVE) String() string {
s := "use tcp keep-alive"
if e.Timeout == 0 {
s += ", timeout omitted"
} else {
s += fmt.Sprintf(", timeout %dms", e.Timeout*100)
}
return
return s
}
func (e *EDNS0_TCP_KEEPALIVE) copy() EDNS0 { return &EDNS0_TCP_KEEPALIVE{e.Code, e.Timeout, e.Length} }
// EDNS0_PADDING option is used to add padding to a request/response. The default
// value of padding SHOULD be 0x0 but other values MAY be used, for instance if
// compression is applied before encryption which may break signatures.
......@@ -628,3 +730,122 @@ func (e *EDNS0_PADDING) Option() uint16 { return EDNS0PADDING }
func (e *EDNS0_PADDING) pack() ([]byte, error) { return e.Padding, nil }
func (e *EDNS0_PADDING) unpack(b []byte) error { e.Padding = b; return nil }
func (e *EDNS0_PADDING) String() string { return fmt.Sprintf("%0X", e.Padding) }
func (e *EDNS0_PADDING) copy() EDNS0 {
b := make([]byte, len(e.Padding))
copy(b, e.Padding)
return &EDNS0_PADDING{b}
}
// Extended DNS Error Codes (RFC 8914).
const (
ExtendedErrorCodeOther uint16 = iota
ExtendedErrorCodeUnsupportedDNSKEYAlgorithm
ExtendedErrorCodeUnsupportedDSDigestType
ExtendedErrorCodeStaleAnswer
ExtendedErrorCodeForgedAnswer
ExtendedErrorCodeDNSSECIndeterminate
ExtendedErrorCodeDNSBogus
ExtendedErrorCodeSignatureExpired
ExtendedErrorCodeSignatureNotYetValid
ExtendedErrorCodeDNSKEYMissing
ExtendedErrorCodeRRSIGsMissing
ExtendedErrorCodeNoZoneKeyBitSet
ExtendedErrorCodeNSECMissing
ExtendedErrorCodeCachedError
ExtendedErrorCodeNotReady
ExtendedErrorCodeBlocked
ExtendedErrorCodeCensored
ExtendedErrorCodeFiltered
ExtendedErrorCodeProhibited
ExtendedErrorCodeStaleNXDOMAINAnswer
ExtendedErrorCodeNotAuthoritative
ExtendedErrorCodeNotSupported
ExtendedErrorCodeNoReachableAuthority
ExtendedErrorCodeNetworkError
ExtendedErrorCodeInvalidData
)
// ExtendedErrorCodeToString maps extended error info codes to a human readable
// description.
var ExtendedErrorCodeToString = map[uint16]string{
ExtendedErrorCodeOther: "Other",
ExtendedErrorCodeUnsupportedDNSKEYAlgorithm: "Unsupported DNSKEY Algorithm",
ExtendedErrorCodeUnsupportedDSDigestType: "Unsupported DS Digest Type",
ExtendedErrorCodeStaleAnswer: "Stale Answer",
ExtendedErrorCodeForgedAnswer: "Forged Answer",
ExtendedErrorCodeDNSSECIndeterminate: "DNSSEC Indeterminate",
ExtendedErrorCodeDNSBogus: "DNSSEC Bogus",
ExtendedErrorCodeSignatureExpired: "Signature Expired",
ExtendedErrorCodeSignatureNotYetValid: "Signature Not Yet Valid",
ExtendedErrorCodeDNSKEYMissing: "DNSKEY Missing",
ExtendedErrorCodeRRSIGsMissing: "RRSIGs Missing",
ExtendedErrorCodeNoZoneKeyBitSet: "No Zone Key Bit Set",
ExtendedErrorCodeNSECMissing: "NSEC Missing",
ExtendedErrorCodeCachedError: "Cached Error",
ExtendedErrorCodeNotReady: "Not Ready",
ExtendedErrorCodeBlocked: "Blocked",
ExtendedErrorCodeCensored: "Censored",
ExtendedErrorCodeFiltered: "Filtered",
ExtendedErrorCodeProhibited: "Prohibited",
ExtendedErrorCodeStaleNXDOMAINAnswer: "Stale NXDOMAIN Answer",
ExtendedErrorCodeNotAuthoritative: "Not Authoritative",
ExtendedErrorCodeNotSupported: "Not Supported",
ExtendedErrorCodeNoReachableAuthority: "No Reachable Authority",
ExtendedErrorCodeNetworkError: "Network Error",
ExtendedErrorCodeInvalidData: "Invalid Data",
}
// StringToExtendedErrorCode is a map from human readable descriptions to
// extended error info codes.
var StringToExtendedErrorCode = reverseInt16(ExtendedErrorCodeToString)
// EDNS0_EDE option is used to return additional information about the cause of
// DNS errors.
type EDNS0_EDE struct {
InfoCode uint16
ExtraText string
}
// Option implements the EDNS0 interface.
func (e *EDNS0_EDE) Option() uint16 { return EDNS0EDE }
func (e *EDNS0_EDE) copy() EDNS0 { return &EDNS0_EDE{e.InfoCode, e.ExtraText} }
func (e *EDNS0_EDE) String() string {
info := strconv.FormatUint(uint64(e.InfoCode), 10)
if s, ok := ExtendedErrorCodeToString[e.InfoCode]; ok {
info += fmt.Sprintf(" (%s)", s)
}
return fmt.Sprintf("%s: (%s)", info, e.ExtraText)
}
func (e *EDNS0_EDE) pack() ([]byte, error) {
b := make([]byte, 2+len(e.ExtraText))
binary.BigEndian.PutUint16(b[0:], e.InfoCode)
copy(b[2:], []byte(e.ExtraText))
return b, nil
}
func (e *EDNS0_EDE) unpack(b []byte) error {
if len(b) < 2 {
return ErrBuf
}
e.InfoCode = binary.BigEndian.Uint16(b[0:])
e.ExtraText = string(b[2:])
return nil
}
// The EDNS0_ESU option for ENUM Source-URI Extension
type EDNS0_ESU struct {
Code uint16
Uri string
}
// Option implements the EDNS0 interface.
func (e *EDNS0_ESU) Option() uint16 { return EDNS0ESU }
func (e *EDNS0_ESU) String() string { return e.Uri }
func (e *EDNS0_ESU) copy() EDNS0 { return &EDNS0_ESU{e.Code, e.Uri} }
func (e *EDNS0_ESU) pack() ([]byte, error) { return []byte(e.Uri), nil }
func (e *EDNS0_ESU) unpack(b []byte) error {
e.Uri = string(b)
return nil
}
......@@ -20,7 +20,7 @@ func Field(r RR, i int) string {
return ""
}
d := reflect.ValueOf(r).Elem().Field(i)
switch k := d.Kind(); k {
switch d.Kind() {
case reflect.String:
return d.String()
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
......@@ -31,6 +31,9 @@ func Field(r RR, i int) string {
switch reflect.ValueOf(r).Elem().Type().Field(i).Tag {
case `dns:"a"`:
// TODO(miek): Hmm store this as 16 bytes
if d.Len() < net.IPv4len {
return ""
}
if d.Len() < net.IPv6len {
return net.IPv4(byte(d.Index(0).Uint()),
byte(d.Index(1).Uint()),
......@@ -42,6 +45,9 @@ func Field(r RR, i int) string {
byte(d.Index(14).Uint()),
byte(d.Index(15).Uint())).String()
case `dns:"aaaa"`:
if d.Len() < net.IPv6len {
return ""
}
return net.IP{
byte(d.Index(0).Uint()),
byte(d.Index(1).Uint()),
......
......@@ -2,6 +2,8 @@
package dns
import "strings"
func Fuzz(data []byte) int {
msg := new(Msg)
......@@ -16,7 +18,14 @@ func Fuzz(data []byte) int {
}
func FuzzNewRR(data []byte) int {
if _, err := NewRR(string(data)); err != nil {
str := string(data)
// Do not fuzz lines that include the $INCLUDE keyword and hint the fuzzer
// at avoiding them.
// See GH#1025 for context.
if strings.Contains(strings.ToUpper(str), "$INCLUDE") {
return -1
}
if _, err := NewRR(str); err != nil {
return 0
}
return 1
......
......@@ -2,8 +2,8 @@ package dns
import (
"bytes"
"errors"
"fmt"
"io"
"strconv"
"strings"
)
......@@ -18,152 +18,230 @@ import (
// * rhs (rdata)
// But we are lazy here, only the range is parsed *all* occurrences
// of $ after that are interpreted.
// Any error are returned as a string value, the empty string signals
// "no error".
func generate(l lex, c chan lex, t chan *Token, o string) string {
step := 1
if i := strings.IndexAny(l.token, "/"); i != -1 {
if i+1 == len(l.token) {
return "bad step in $GENERATE range"
func (zp *ZoneParser) generate(l lex) (RR, bool) {
token := l.token
step := int64(1)
if i := strings.IndexByte(token, '/'); i >= 0 {
if i+1 == len(token) {
return zp.setParseError("bad step in $GENERATE range", l)
}
if s, err := strconv.Atoi(l.token[i+1:]); err == nil {
if s < 0 {
return "bad step in $GENERATE range"
}
step = s
} else {
return "bad step in $GENERATE range"
s, err := strconv.ParseInt(token[i+1:], 10, 64)
if err != nil || s <= 0 {
return zp.setParseError("bad step in $GENERATE range", l)
}
l.token = l.token[:i]
step = s
token = token[:i]
}
sx := strings.SplitN(l.token, "-", 2)
sx := strings.SplitN(token, "-", 2)
if len(sx) != 2 {
return "bad start-stop in $GENERATE range"
return zp.setParseError("bad start-stop in $GENERATE range", l)
}
start, err := strconv.Atoi(sx[0])
start, err := strconv.ParseInt(sx[0], 10, 64)
if err != nil {
return "bad start in $GENERATE range"
return zp.setParseError("bad start in $GENERATE range", l)
}
end, err := strconv.Atoi(sx[1])
end, err := strconv.ParseInt(sx[1], 10, 64)
if err != nil {
return "bad stop in $GENERATE range"
return zp.setParseError("bad stop in $GENERATE range", l)
}
if end < 0 || start < 0 || end < start {
return "bad range in $GENERATE range"
if end < 0 || start < 0 || end < start || (end-start)/step > 65535 {
return zp.setParseError("bad range in $GENERATE range", l)
}
// _BLANK
l, ok := zp.c.Next()
if !ok || l.value != zBlank {
return zp.setParseError("garbage after $GENERATE range", l)
}
<-c // _BLANK
// Create a complete new string, which we then parse again.
s := ""
BuildRR:
l = <-c
if l.value != zNewline && l.value != zEOF {
var s string
for l, ok := zp.c.Next(); ok; l, ok = zp.c.Next() {
if l.err {
return zp.setParseError("bad data in $GENERATE directive", l)
}
if l.value == zNewline {
break
}
s += l.token
goto BuildRR
}
for i := start; i <= end; i += step {
var (
escape bool
dom bytes.Buffer
mod string
err error
offset int
)
for j := 0; j < len(s); j++ { // No 'range' because we need to jump around
switch s[j] {
case '\\':
if escape {
dom.WriteByte('\\')
escape = false
continue
}
escape = true
case '$':
mod = "%d"
offset = 0
if escape {
dom.WriteByte('$')
escape = false
continue
}
escape = false
if j+1 >= len(s) { // End of the string
dom.WriteString(fmt.Sprintf(mod, i+offset))
continue
} else {
if s[j+1] == '$' {
dom.WriteByte('$')
j++
continue
}
}
// Search for { and }
if s[j+1] == '{' { // Modifier block
sep := strings.Index(s[j+2:], "}")
if sep == -1 {
return "bad modifier in $GENERATE"
}
mod, offset, err = modToPrintf(s[j+2 : j+2+sep])
if err != nil {
return err.Error()
}
j += 2 + sep // Jump to it
}
dom.WriteString(fmt.Sprintf(mod, i+offset))
default:
if escape { // Pretty useless here
escape = false
continue
}
dom.WriteByte(s[j])
}
r := &generateReader{
s: s,
cur: start,
start: start,
end: end,
step: step,
file: zp.file,
lex: &l,
}
zp.sub = NewZoneParser(r, zp.origin, zp.file)
zp.sub.includeDepth, zp.sub.includeAllowed = zp.includeDepth, zp.includeAllowed
zp.sub.generateDisallowed = true
zp.sub.SetDefaultTTL(defaultTtl)
return zp.subNext()
}
type generateReader struct {
s string
si int
cur int64
start int64
end int64
step int64
mod bytes.Buffer
escape bool
eof bool
file string
lex *lex
}
func (r *generateReader) parseError(msg string, end int) *ParseError {
r.eof = true // Make errors sticky.
l := *r.lex
l.token = r.s[r.si-1 : end]
l.column += r.si // l.column starts one zBLANK before r.s
return &ParseError{r.file, msg, l}
}
func (r *generateReader) Read(p []byte) (int, error) {
// NewZLexer, through NewZoneParser, should use ReadByte and
// not end up here.
panic("not implemented")
}
func (r *generateReader) ReadByte() (byte, error) {
if r.eof {
return 0, io.EOF
}
if r.mod.Len() > 0 {
return r.mod.ReadByte()
}
if r.si >= len(r.s) {
r.si = 0
r.cur += r.step
r.eof = r.cur > r.end || r.cur < 0
return '\n', nil
}
si := r.si
r.si++
switch r.s[si] {
case '\\':
if r.escape {
r.escape = false
return '\\', nil
}
r.escape = true
return r.ReadByte()
case '$':
if r.escape {
r.escape = false
return '$', nil
}
mod := "%d"
if si >= len(r.s)-1 {
// End of the string
fmt.Fprintf(&r.mod, mod, r.cur)
return r.mod.ReadByte()
}
if r.s[si+1] == '$' {
r.si++
return '$', nil
}
var offset int64
// Search for { and }
if r.s[si+1] == '{' {
// Modifier block
sep := strings.Index(r.s[si+2:], "}")
if sep < 0 {
return 0, r.parseError("bad modifier in $GENERATE", len(r.s))
}
var errMsg string
mod, offset, errMsg = modToPrintf(r.s[si+2 : si+2+sep])
if errMsg != "" {
return 0, r.parseError(errMsg, si+3+sep)
}
if r.start+offset < 0 || r.end+offset > 1<<31-1 {
return 0, r.parseError("bad offset in $GENERATE", si+3+sep)
}
r.si += 2 + sep // Jump to it
}
// Re-parse the RR and send it on the current channel t
rx, err := NewRR("$ORIGIN " + o + "\n" + dom.String())
if err != nil {
return err.Error()
fmt.Fprintf(&r.mod, mod, r.cur+offset)
return r.mod.ReadByte()
default:
if r.escape { // Pretty useless here
r.escape = false
return r.ReadByte()
}
t <- &Token{RR: rx}
// Its more efficient to first built the rrlist and then parse it in
// one go! But is this a problem?
return r.s[si], nil
}
return ""
}
// Convert a $GENERATE modifier 0,0,d to something Printf can deal with.
func modToPrintf(s string) (string, int, error) {
xs := strings.Split(s, ",")
func modToPrintf(s string) (string, int64, string) {
// Modifier is { offset [ ,width [ ,base ] ] } - provide default
// values for optional width and type, if necessary.
switch len(xs) {
var offStr, widthStr, base string
switch xs := strings.Split(s, ","); len(xs) {
case 1:
xs = append(xs, "0", "d")
offStr, widthStr, base = xs[0], "0", "d"
case 2:
xs = append(xs, "d")
offStr, widthStr, base = xs[0], xs[1], "d"
case 3:
offStr, widthStr, base = xs[0], xs[1], xs[2]
default:
return "", 0, errors.New("bad modifier in $GENERATE")
return "", 0, "bad modifier in $GENERATE"
}
// xs[0] is offset, xs[1] is width, xs[2] is base
if xs[2] != "o" && xs[2] != "d" && xs[2] != "x" && xs[2] != "X" {
return "", 0, errors.New("bad base in $GENERATE")
switch base {
case "o", "d", "x", "X":
default:
return "", 0, "bad base in $GENERATE"
}
offset, err := strconv.Atoi(xs[0])
if err != nil || offset > 255 {
return "", 0, errors.New("bad offset in $GENERATE")
offset, err := strconv.ParseInt(offStr, 10, 64)
if err != nil {
return "", 0, "bad offset in $GENERATE"
}
width, err := strconv.Atoi(xs[1])
if err != nil || width > 255 {
return "", offset, errors.New("bad width in $GENERATE")
width, err := strconv.ParseInt(widthStr, 10, 64)
if err != nil || width < 0 || width > 255 {
return "", 0, "bad width in $GENERATE"
}
switch {
case width < 0:
return "", offset, errors.New("bad width in $GENERATE")
case width == 0:
return "%" + xs[1] + xs[2], offset, nil
if width == 0 {
return "%" + base, offset, ""
}
return "%0" + xs[1] + xs[2], offset, nil
return "%0" + widthStr + base, offset, ""
}
package dns
import (
"bytes"
"crypto"
"hash"
)
// identityHash will not hash, it only buffers the data written into it and returns it as-is.
type identityHash struct {
b *bytes.Buffer
}
// Implement the hash.Hash interface.
func (i identityHash) Write(b []byte) (int, error) { return i.b.Write(b) }
func (i identityHash) Size() int { return i.b.Len() }
func (i identityHash) BlockSize() int { return 1024 }
func (i identityHash) Reset() { i.b.Reset() }
func (i identityHash) Sum(b []byte) []byte { return append(b, i.b.Bytes()...) }
func hashFromAlgorithm(alg uint8) (hash.Hash, crypto.Hash, error) {
hashnumber, ok := AlgorithmToHash[alg]
if !ok {
return nil, 0, ErrAlg
}
if hashnumber == 0 {
return identityHash{b: &bytes.Buffer{}}, hashnumber, nil
}
return hashnumber.New(), hashnumber, nil
}
......@@ -10,13 +10,13 @@ package dns
// escaped dots (\.) for instance.
// s must be a syntactically valid domain name, see IsDomainName.
func SplitDomainName(s string) (labels []string) {
if len(s) == 0 {
if s == "" {
return nil
}
fqdnEnd := 0 // offset of the final '.' or the length of the name
idx := Split(s)
begin := 0
if s[len(s)-1] == '.' {
if IsFqdn(s) {
fqdnEnd = len(s) - 1
} else {
fqdnEnd = len(s)
......@@ -28,16 +28,13 @@ func SplitDomainName(s string) (labels []string) {
case 1:
// no-op
default:
end := 0
for i := 1; i < len(idx); i++ {
end = idx[i]
for _, end := range idx[1:] {
labels = append(labels, s[begin:end-1])
begin = end
}
}
labels = append(labels, s[begin:fqdnEnd])
return labels
return append(labels, s[begin:fqdnEnd])
}
// CompareDomainName compares the names s1 and s2 and
......@@ -86,7 +83,7 @@ func CompareDomainName(s1, s2 string) (n int) {
return
}
// CountLabel counts the the number of labels in the string s.
// CountLabel counts the number of labels in the string s.
// s must be a syntactically valid domain name.
func CountLabel(s string) (labels int) {
if s == "." {
......@@ -129,20 +126,23 @@ func Split(s string) []int {
// The bool end is true when the end of the string has been reached.
// Also see PrevLabel.
func NextLabel(s string, offset int) (i int, end bool) {
quote := false
if s == "" {
return 0, true
}
for i = offset; i < len(s)-1; i++ {
switch s[i] {
case '\\':
quote = !quote
default:
quote = false
case '.':
if quote {
quote = !quote
continue
}
return i + 1, false
if s[i] != '.' {
continue
}
j := i - 1
for j >= 0 && s[j] == '\\' {
j--
}
if (j-i)%2 == 0 {
continue
}
return i + 1, false
}
return i + 1, true
}
......@@ -152,17 +152,38 @@ func NextLabel(s string, offset int) (i int, end bool) {
// The bool start is true when the start of the string has been overshot.
// Also see NextLabel.
func PrevLabel(s string, n int) (i int, start bool) {
if s == "" {
return 0, true
}
if n == 0 {
return len(s), false
}
lab := Split(s)
if lab == nil {
return 0, true
l := len(s) - 1
if s[l] == '.' {
l--
}
if n > len(lab) {
return 0, true
for ; l >= 0 && n > 0; l-- {
if s[l] != '.' {
continue
}
j := l - 1
for j >= 0 && s[j] == '\\' {
j--
}
if (j-l)%2 == 0 {
continue
}
n--
if n == 0 {
return l + 1, false
}
}
return lab[len(lab)-n], false
return 0, n > 1
}
// equal compares a and b while ignoring case. It returns true when equal otherwise false.
......