diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..62c8935
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+.idea/
\ No newline at end of file
diff --git a/LICENSE b/LICENSE
new file mode 100644
index 0000000..261eeb9
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
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+      the terms of any separate license agreement you may have executed
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+   6. Trademarks. This License does not grant permission to use the trade
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diff --git a/README.md b/README.md
new file mode 100644
index 0000000..4e21f3c
--- /dev/null
+++ b/README.md
@@ -0,0 +1,76 @@
+# Go DANE
+
+**Note: Go DANE is still under development, use at your own risk.**
+
+
+Go DANE enables the use of DANE/TLSA in browsers using a simple proxy. It currently supports [DANE](https://tools.ietf.org/html/rfc6698) EE(3), and works with self-signed certificates.
+
+
+
+
+<p align="center">
+<img src="screenshot.png" width="400px" alt="Go DANE verified DNSSEC"/><br/>
+</p>
+
+## How it works
+
+Go DANE mitms HTTPS for sites that support DANE.  It requires one root CA to be installed locally. Go DANE will use the root CA to create certificates on the fly if it was able to verify DANE/TLSA.
+It won't mitm sites that don't use DANE/TLSA and will serve their original certificate instead.
+ 
+
+## Usage
+
+Download the latest pre-built binary for your OS from [releases](https://github.com.) and run
+
+
+    ./godane -dns tls://1.1.1.1
+    
+* Add Go DANE proxy to your web browser `127.0.0.1:8080` (see [Firefox instructions](doc/firefox.md)). Make sure to add it for HTTPS as well. 
+
+* Visit `http://godane.test` and click install certificate.
+
+
+
+Note: When you run Go DANE for the first time, it will generate a root CA and store it in `~/.godane`.
+The easiest way to try it out is to use Firefox because it supports adding a proxy natively and has a built in CA store so that you don't have to add the root CA or proxy to your whole OS (it's still experimental). 
+
+#### Some sites that currently use DANE-EE(3):
+* FreeBSD: https://freebsd.org
+
+* Tor Project: https://torproject.org
+
+* Kumari https://www.kumari.net/
+
+and more?
+
+### Go DANE with handshake.org
+
+If you're running a local hsd node listening for dns queries:
+
+    ./godane -dns udp://:53
+
+You can also use [easyhandshake](https://easyhandshake.com) resolver.
+
+    ./godane -dns https://easyhandshake.com:8053
+    
+    
+Note: You can configure hsd to use a different port if 53 is in use.
+
+## Use of resolvers
+
+Go DANE doesn't perform DNSSEC verficiation by itself. The resolver you specify must be DNSSEC capable. If you have a local resolver that is DNSSEC capable, you can use udp or tcp. If not, please use a trusted resolver that supports DNSSEC and uses DOT or DOH.
+
+Note: Go DANE will ignore TLSA responses that don't come with the [Authenticaed Data (AD)](https://tools.ietf.org/html/rfc3655) flag.
+
+## Why?
+
+I wanted to use DANE/TLSA, but no browser currently supports it. Also, it appears that it's [not possible](https://www.dnssec-validator.cz/) to support it via an extension. So this seemed like a fun idea to try, and with [martian](https://github.com/google/martian), it was pretty easy.
+
+
+ 
+## Contributing
+
+Contributions are welcome! 
+
+
+
diff --git a/cache.go b/cache.go
new file mode 100644
index 0000000..9314dd8
--- /dev/null
+++ b/cache.go
@@ -0,0 +1,59 @@
+package godane
+
+import (
+	"github.com/miekg/dns"
+	"sync"
+	"time"
+)
+
+type entry struct {
+	msg []dns.RR
+	ttl time.Time
+}
+
+type cache struct {
+	m    map[string]*entry
+	maxN int
+
+	sync.RWMutex
+}
+
+func newCache(maxN int) (m *cache) {
+	return &cache{m: make(map[string]*entry), maxN: maxN}
+}
+
+func (c *cache) set(key string, item *entry) {
+	c.Lock()
+	defer c.Unlock()
+
+	if c.maxN == len(c.m) {
+		for k := range c.m {
+			delete(c.m, k)
+			break
+		}
+	}
+
+	c.m[key] = item
+}
+
+func (c *cache) get(key string) (*entry, bool) {
+	c.RLock()
+	defer c.RUnlock()
+
+	i, ok := c.m[key]
+	return i, ok
+}
+
+func (c *cache) remove(key string) {
+	c.Lock()
+	defer c.Unlock()
+
+	delete(c.m, key)
+}
+
+func (c *cache) len() int {
+	c.RLock()
+	defer c.RUnlock()
+
+	return len(c.m)
+}
diff --git a/cache_test.go b/cache_test.go
new file mode 100644
index 0000000..8dbbf5a
--- /dev/null
+++ b/cache_test.go
@@ -0,0 +1,25 @@
+package godane
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestCache(t *testing.T) {
+	maxCache := 10
+	c := newCache(maxCache)
+
+	for i := 0; i < 30; i++ {
+		c.set(fmt.Sprintf("test%d", i), &entry{})
+	}
+
+	_, ok := c.get("test29")
+
+	if !ok {
+		t.Fatal("want key `test29`")
+	}
+
+	if c.len() > maxCache {
+		t.Fatalf("want cache len = %d, got %d", maxCache, c.len())
+	}
+}
diff --git a/cmd/godane/main.go b/cmd/godane/main.go
new file mode 100644
index 0000000..8b85909
--- /dev/null
+++ b/cmd/godane/main.go
@@ -0,0 +1,326 @@
+package main
+
+import (
+	"bytes"
+	"crypto/tls"
+	"crypto/x509"
+	"encoding/pem"
+	"flag"
+	"github.com/google/martian/v3"
+	mapi "github.com/google/martian/v3/api"
+	"github.com/google/martian/v3/fifo"
+	"github.com/google/martian/v3/httpspec"
+	"github.com/google/martian/v3/martianhttp"
+	"github.com/google/martian/v3/mitm"
+	"github.com/google/martian/v3/servemux"
+	"godane"
+	"html/template"
+	"io/ioutil"
+	"log"
+	"net"
+	"net/http"
+	"os"
+	"path"
+	"strconv"
+	"strings"
+	"time"
+)
+
+var (
+	resolver = flag.String("dns", "tls://1.1.1.1", "dns resolver udp://, tcp://, tls:// or https://")
+	conf     = flag.String("dir", "", "dir path to store configuration (default: ~/.godane)")
+	addr     = flag.String("addr", ":8080", "host:port of the proxy")
+	apiAddr  = flag.String("api-addr", ":8181", "host:port of the configuration api")
+	cert     = flag.String("cert", "", "filepath to the CA (leave empty to auto generate)")
+	key      = flag.String("key", "", "filepath to the private key of the CA")
+	validity = flag.Duration("validity", time.Hour, "window of time generated DANE certificates are valid")
+)
+
+var badGatewayTmpl = `
+<!DOCTYPE html>
+<html>
+<head>
+<style>
+body {
+    font-size: 16px;
+    font-family: -apple-system,BlinkMacSystemFont,Segoe UI,PingFang SC,Hiragino Sans GB,Microsoft YaHei,Helvetica Neue,Helvetica,Arial,sans-serif,Apple Color Emoji,Segoe UI Emoji,Segoe UI Symbol;
+}
+h1 {
+    color:#481380;
+}
+</style>
+</head>
+<body>
+<div style="margin: 0 auto; text-align: center; margin-top: 6em;">
+<h1>HTTP 502 - Bad Gateway</h1><p>An error occurred while making this request: </p><br>
+<pre>`
+
+var daneSetupTmpl = `
+<!DOCTYPE html>
+<html>
+<head>
+<style>
+body {
+    font-size: 16px;
+    font-family: -apple-system,BlinkMacSystemFont,Segoe UI,PingFang SC,Hiragino Sans GB,Microsoft YaHei,Helvetica Neue,Helvetica,Arial,sans-serif,Apple Color Emoji,Segoe UI Emoji,Segoe UI Symbol;
+}
+h1 {
+    color:#481380;
+}
+.c {
+    max-width:600px;margin:0 auto;margin-top:6em;
+}
+.btn {
+    background-color:#481380;color:#fff;
+    border:none;
+    border-radius:4px;
+    padding:.8em;margin-left:.1em;
+    text-decoration:none;
+}
+    </style>
+</head>
+<body>
+	<div class="c">
+		<h1>Go DANE Setup</h1>
+        <h3>Install Certificate</h3>
+		<p>The root CA has been generated and stored at <code>{{.CertPath}}</code>. <br>
+         </p>
+         <p>Add this certificate to your browser's trusted root certificates. It will be used to generate certificates for websites that use DANE.</p>
+        <br><br><br>
+        <a href="{{.CertURL}}" class="btn">Install Certificate</a>
+    </div>
+    </div>
+  </body>
+</html>
+`
+
+const certEndpoint = "/authority.cer"
+const godaneHost = "godane.test"
+
+var indexTmpl *template.Template
+
+type indexTmplData struct {
+	CertPath string
+	CertURL  string
+}
+
+func getConfPath() string {
+	if *conf != "" {
+		return *conf
+	}
+
+	home, err := os.UserHomeDir()
+	if err != nil {
+		log.Fatalf("failed to get home dir: %v", err)
+	}
+
+	p := path.Join(home, ".godane")
+
+	if _, err := os.Stat(p); err != nil {
+		if err := os.Mkdir(p, 0700); err != nil {
+			log.Fatalf("failed to create conf dir: %v", err)
+		}
+	}
+
+	return p
+}
+
+func generateCA() (string, string) {
+	if *cert != "" && *key != "" {
+		return *cert, *key
+	}
+
+	p := getConfPath()
+	ca, priv, err := mitm.NewAuthority("DNSSEC", "DNSSEC", 365*24*time.Hour)
+	if err != nil {
+		log.Fatalf("couldn't generate CA: %v", err)
+	}
+
+	certPath := path.Join(p, "cert.crt")
+	keyPath := path.Join(p, "cert.key")
+
+	if _, err := os.Stat(certPath); err != nil {
+
+		cOut, err := os.Create(certPath)
+		if err != nil {
+			log.Fatalf("couldn't create CA file: %v", err)
+		}
+
+		// pem encode
+		pem.Encode(cOut, &pem.Block{
+			Type:  "CERTIFICATE",
+			Bytes: ca.Raw,
+		})
+
+		if err := cOut.Close(); err != nil {
+			log.Fatalf("couldn't close CA file: %v", err)
+		}
+
+		kOut, err := os.Create(keyPath)
+		if err != nil {
+			log.Fatalf("couldn't create CA key file: %v", err)
+		}
+
+		pem.Encode(kOut, &pem.Block{
+			Type:  "RSA PRIVATE KEY",
+			Bytes: x509.MarshalPKCS1PrivateKey(priv),
+		})
+
+		if err := kOut.Close(); err != nil {
+			log.Fatalf("couldn't close CA key file: %v", err)
+		}
+	}
+
+	return certPath, keyPath
+}
+
+func setupMITM(p *martian.Proxy, mux *http.ServeMux, rs godane.Resolver) {
+	var x509c *x509.Certificate
+	var priv interface{}
+
+	*cert, *key = generateCA()
+	if *cert != "" && *key != "" {
+		tlsc, err := tls.LoadX509KeyPair(*cert, *key)
+		if err != nil {
+			log.Fatal(err)
+		}
+		priv = tlsc.PrivateKey
+
+		x509c, err = x509.ParseCertificate(tlsc.Certificate[0])
+		if err != nil {
+			log.Fatal(err)
+		}
+	}
+
+	if x509c != nil && priv != nil {
+		mc, err := mitm.NewConfig(x509c, priv)
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		mc.SetValidity(*validity)
+		mc.SetOrganization("DNSSEC")
+		p.SetMITM(mc)
+		p.SkipMITM(func(req *http.Request) bool {
+			prefix := godane.GetTLSAPrefix(req.Host)
+			if ans, err := rs.LookupTLSA(prefix); err == nil && godane.TLSASupported(ans) {
+				return false
+			}
+			return true
+		})
+
+		// Expose certificate authority.
+		ah := martianhttp.NewAuthorityHandler(x509c)
+		configure(certEndpoint, ah, mux)
+		configure("/", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			indexTmpl.Execute(w, indexTmplData{
+				CertPath: *cert,
+				CertURL:  "http://" + path.Join(godaneHost, certEndpoint),
+			})
+		}), mux)
+	}
+}
+
+func main() {
+	p := martian.NewProxy()
+	defer p.Close()
+
+	rs, err := godane.NewResolver(*resolver)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	tr := godane.RoundTripper(rs)
+	p.SetRoundTripper(tr)
+	p.SetDial(godane.GetDialFunc(rs))
+
+	mux := http.NewServeMux()
+	setupMITM(p, mux, rs)
+
+	// Note: this part uses the same forwarding logic in the original martian proxy[0]
+	//  to handle requests for http://godane.test
+	// [0]: https://github.com/google/martian/blob/master/cmd/proxy/main.go
+
+	stack, fg := httpspec.NewStack("martian")
+
+	// wrap stack in a group so that we can forward API requests to the API port
+	// before the httpspec modifiers which include the via modifier which will
+	// trip loop detection
+	topg := fifo.NewGroup()
+
+	// Redirect API traffic to API server.
+	if *apiAddr != "" {
+		apip := strings.Replace(*apiAddr, ":", "", 1)
+		port, err := strconv.Atoi(apip)
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		// Forward traffic that pattern matches in http.DefaultServeMux
+		apif := servemux.NewFilter(mux)
+		apif.SetRequestModifier(mapi.NewForwarder("", port))
+		topg.AddRequestModifier(apif)
+	}
+	topg.AddRequestModifier(stack)
+	topg.AddResponseModifier(stack)
+	topg.AddResponseModifier(martian.ResponseModifierFunc(func(res *http.Response) error {
+		if res.StatusCode == 502 {
+			// format:199 "martian" "error message" "date"
+			w := strings.TrimSpace(res.Header.Get("Warning"))
+			p := strings.Split(w, `"`)
+			if len(p) != 7 {
+				return nil
+			}
+
+			msg := p[3]
+			raw := []byte(badGatewayTmpl + msg)
+			res.ContentLength = int64(len(raw))
+			res.Header.Set("Content-Length", strconv.Itoa(len(raw)))
+			res.Body = ioutil.NopCloser(bytes.NewReader(raw))
+		}
+
+		return nil
+	}))
+
+	p.SetRequestModifier(topg)
+	p.SetResponseModifier(topg)
+
+	m := martianhttp.NewModifier()
+	fg.AddRequestModifier(m)
+	fg.AddResponseModifier(m)
+
+	l, err := net.Listen("tcp", *addr)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	lAPI, err := net.Listen("tcp", *apiAddr)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	log.Printf("godane: starting proxy on %s and api on %s", l.Addr().String(), lAPI.Addr().String())
+
+	go p.Serve(l)
+	http.Serve(lAPI, mux)
+}
+
+func init() {
+	var err error
+	indexTmpl, err = template.New("index").Parse(daneSetupTmpl)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	martian.Init()
+}
+
+// configure installs a configuration handler at path.
+func configure(pattern string, handler http.Handler, mux *http.ServeMux) {
+	// register handler for godane.test
+	mux.Handle(godaneHost+pattern, handler)
+
+	// register handler for local server
+	p := path.Join("localhost"+*apiAddr, pattern)
+	mux.Handle(p, handler)
+}
diff --git a/doc/firefox.md b/doc/firefox.md
new file mode 100644
index 0000000..53b5f88
--- /dev/null
+++ b/doc/firefox.md
@@ -0,0 +1,16 @@
+# Use Go DANE with Firefox
+
+Go to Preferences -> Network Settings
+
+Add the proxy for http and https. Click ok.
+
+![Firefox Proxy Settings](network-settings.png)
+
+
+Visit `http://godane.test` and click install certificate.
+
+![godane.test install certificate](godane.test.png)
+
+
+
+That's it. You can now visit sites that use DANE.
\ No newline at end of file
diff --git a/doc/godane.test.png b/doc/godane.test.png
new file mode 100644
index 0000000..00dadd2
Binary files /dev/null and b/doc/godane.test.png differ
diff --git a/doc/network-settings.png b/doc/network-settings.png
new file mode 100644
index 0000000..6647470
Binary files /dev/null and b/doc/network-settings.png differ
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..914a521
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,10 @@
+module godane
+
+go 1.13
+
+replace github.com/google/martian/v3 => github.com/buffrr/martian/v3 v3.0.1-0.20200408012421-ffcd9db35185
+
+require (
+	github.com/google/martian/v3 v3.0.0
+	github.com/miekg/dns v1.1.29
+)
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..51993d5
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,21 @@
+github.com/buffrr/martian/v3 v3.0.1-0.20200408012421-ffcd9db35185 h1:sFbj1GreDVRAFz0NYPG5UkPVdffmqFvsDa+INlkJ5Mo=
+github.com/buffrr/martian/v3 v3.0.1-0.20200408012421-ffcd9db35185/go.mod h1:y5Zk1BBys9G+gd6Jrk0W3cC1+ELVxBWuIGO+w/tUAp0=
+github.com/miekg/dns v1.1.29 h1:xHBEhR+t5RzcFJjBLJlax2daXOrTYtr9z4WdKEfWFzg=
+github.com/miekg/dns v1.1.29/go.mod h1:KNUDUusw/aVsxyTYZM1oqvCicbwhgbNgztCETuNZ7xM=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550 h1:ObdrDkeb4kJdCP557AjRjq69pTHfNouLtWZG7j9rPN8=
+golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
+golang.org/x/mod v0.1.1-0.20191105210325-c90efee705ee/go.mod h1:QqPTAvyqsEbceGzBzNggFXnrqF1CaUcvgkdR5Ot7KZg=
+golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/net v0.0.0-20190628185345-da137c7871d7/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/net v0.0.0-20190923162816-aa69164e4478 h1:l5EDrHhldLYb3ZRHDUhXF7Om7MvYXnkV9/iQNo1lX6g=
+golang.org/x/net v0.0.0-20190923162816-aa69164e4478/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20190924154521-2837fb4f24fe h1:6fAMxZRR6sl1Uq8U61gxU+kPTs2tR8uOySCbBP7BN/M=
+golang.org/x/sys v0.0.0-20190924154521-2837fb4f24fe/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+golang.org/x/tools v0.0.0-20191216052735-49a3e744a425/go.mod h1:TB2adYChydJhpapKDTa4BR/hXlZSLoq2Wpct/0txZ28=
+golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
diff --git a/resolver.go b/resolver.go
new file mode 100644
index 0000000..a815556
--- /dev/null
+++ b/resolver.go
@@ -0,0 +1,324 @@
+package godane
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"github.com/miekg/dns"
+	"io/ioutil"
+	"net"
+	"net/http"
+	"net/url"
+	"strings"
+	"sync"
+	"time"
+)
+
+// Resolver looks up names
+type Resolver interface {
+	LookupIP(string) ([]net.IP, error)
+	LookupTLSA(string) ([]dns.TLSA, error)
+}
+
+// ClientResolver implements Resolver and caches queries.
+type ClientResolver struct {
+	rrCache  map[uint16]*cache
+	client   *dns.Client
+	protocol string
+	address  string
+}
+
+const (
+	minTTL = 10 * time.Second
+	maxTTL = 3 * time.Hour
+	// max cache len for each rr type
+	maxCache = 10000
+)
+
+// NewResolver creates a new resolver
+// the server can be specified using udp://, tcp://, tls:// or https://
+func NewResolver(server string) (*ClientResolver, error) {
+	address, protocol, err := parseAddress(server)
+	if err != nil {
+		return nil, err
+	}
+
+	client := new(dns.Client)
+	client.Net = protocol
+	rrCache := make(map[uint16]*cache)
+	rrCache[dns.TypeA] = newCache(maxCache)
+	rrCache[dns.TypeAAAA] = newCache(maxCache)
+	rrCache[dns.TypeTLSA] = newCache(maxCache)
+
+	return &ClientResolver{
+		rrCache:  rrCache,
+		client:   client,
+		protocol: protocol,
+		address:  address,
+	}, nil
+}
+
+func parseAddress(server string) (string, string, error) {
+	u, err := url.Parse(server)
+	if err != nil {
+		return "", "", fmt.Errorf("dns: couldn't parse server address: %v", err)
+	}
+
+	var p, defaultPort string
+	host := u.Host
+
+	switch u.Scheme {
+	case "udp":
+		defaultPort = "53"
+		p = ""
+	case "tcp":
+		p = u.Scheme
+		defaultPort = "53"
+	case "tls":
+		p = "tcp-tls"
+		defaultPort = "853"
+	case "https":
+		p = u.Scheme
+		host = u.Scheme + "://" + u.Host
+	default:
+		return "", "", fmt.Errorf("dns: unsupported scheme %s", u.Scheme)
+	}
+
+	_, _, err = net.SplitHostPort(u.Host)
+	if err != nil && u.Scheme != "https" {
+		return net.JoinHostPort(host, defaultPort), p, nil
+	}
+
+	return host, p, nil
+
+}
+
+func (rs *ClientResolver) exchange(m *dns.Msg) (r *dns.Msg, rtt time.Duration, err error) {
+	if rs.protocol == "https" {
+		return rs.exchangeDOH(m)
+	}
+	return rs.client.Exchange(m, rs.address)
+}
+
+func (rs *ClientResolver) exchangeDOH(m *dns.Msg) (r *dns.Msg, rtt time.Duration, err error) {
+	buf, err := m.Pack()
+	if err != nil {
+		return nil, 0, err
+	}
+
+	req, err := http.NewRequest(http.MethodPost, rs.address+"/dns-query", bytes.NewReader(buf))
+	if err != nil {
+		return nil, 0, err
+	}
+
+	req.Header.Set("content-type", "application/dns-message")
+	req.Header.Set("accept", "application/dns-message")
+
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return nil, 0, err
+	}
+
+	if resp.StatusCode != http.StatusOK {
+		return nil, 0, fmt.Errorf("dns: %s", resp.Status)
+	}
+
+	defer resp.Body.Close()
+	b, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return nil, 0, err
+	}
+
+	ans := new(dns.Msg)
+	err = ans.Unpack(b)
+
+	return ans, 0, err
+}
+
+func (rs *ClientResolver) checkCache(key string, qtype uint16) (*entry, bool) {
+	if ans, ok := rs.rrCache[qtype].get(key); ok {
+		if time.Now().Before(ans.ttl) {
+			return ans, true
+		}
+
+		rs.rrCache[qtype].remove(key)
+	}
+
+	return nil, false
+}
+
+// LookupIP looks up host using the specified resolver.
+// It returns a slice of that host's IPv4 and IPv6 addresses.
+func (rs *ClientResolver) LookupIP(hostname string) ([]net.IP, error) {
+	ip := net.ParseIP(hostname)
+	if ip != nil {
+		return []net.IP{ip}, nil
+	}
+
+	if !shouldResolve(hostname) {
+		return net.LookupIP(hostname)
+	}
+
+	var wg sync.WaitGroup
+	var ipv4, ipv6 []net.IP
+	var err1, err2 error
+
+	wg.Add(2)
+	go func() {
+		ipv4, err1 = rs.lookupIPv4(hostname)
+		wg.Done()
+	}()
+
+	go func() {
+		ipv6, err2 = rs.lookupIPv4(hostname)
+		wg.Done()
+	}()
+
+	wg.Wait()
+
+	if err1 != nil {
+		return nil, err1
+	}
+
+	if err2 != nil {
+		return nil, err2
+	}
+
+	return append(ipv4, ipv6...), nil
+}
+
+func (rs *ClientResolver) lookupIPv4(hostname string) ([]net.IP, error) {
+	rr, err := rs.lookup(hostname, dns.TypeA)
+	if err != nil {
+		return nil, err
+	}
+	var ips []net.IP
+	for _, r := range rr {
+		switch t := r.(type) {
+		case *dns.A:
+			ips = append(ips, t.A)
+		}
+	}
+	return ips, nil
+}
+
+func (rs *ClientResolver) lookupIPv6(hostname string) ([]net.IP, error) {
+	rr, err := rs.lookup(hostname, dns.TypeAAAA)
+	if err != nil {
+		return nil, err
+	}
+	var ips []net.IP
+	for _, r := range rr {
+		switch t := r.(type) {
+		case *dns.AAAA:
+			ips = append(ips, t.AAAA)
+		}
+	}
+	return ips, nil
+}
+
+// LookupTLSA returns TLSA records for the given TLSA prefix.
+func (rs *ClientResolver) LookupTLSA(prefix string) ([]dns.TLSA, error) {
+	rr, err := rs.lookup(prefix, dns.TypeTLSA)
+	if err != nil {
+		return nil, err
+	}
+
+	var tr []dns.TLSA
+	for _, r := range rr {
+		switch t := r.(type) {
+		case *dns.TLSA:
+			tr = append(tr, *t)
+		}
+	}
+
+	return tr, nil
+}
+
+func (rs *ClientResolver) lookup(name string, qtype uint16) ([]dns.RR, error) {
+	if ans, ok := rs.checkCache(name, qtype); ok {
+		return ans.msg, nil
+	}
+
+	m := new(dns.Msg)
+	m.SetQuestion(dns.Fqdn(name), qtype)
+	m.RecursionDesired = true
+	m.AuthenticatedData = true
+
+	r, _, err := rs.exchange(m)
+	if err != nil {
+		return nil, err
+	}
+
+	if r.Truncated {
+		return nil, errors.New("dns: response truncated")
+	}
+
+	if qtype == dns.TypeTLSA && !r.AuthenticatedData {
+		return nil, errors.New("dns: resolver didn't confirm msg (no ad flag)")
+	}
+
+	e := &entry{
+		msg: r.Answer,
+		ttl: time.Now().Add(getMinTTL(r)),
+	}
+
+	rs.rrCache[qtype].set(name, e)
+
+	return r.Answer, nil
+}
+
+// getMinTTL get the ttl for dns msg
+// borrowed from coredns: https://github.com/coredns/coredns/blob/master/plugin/pkg/dnsutil/ttl.go
+func getMinTTL(m *dns.Msg) time.Duration {
+	// No records or OPT is the only record, return a short ttl as a fail safe.
+	if len(m.Answer)+len(m.Ns) == 0 &&
+		(len(m.Extra) == 0 || (len(m.Extra) == 1 && m.Extra[0].Header().Rrtype == dns.TypeOPT)) {
+		return minTTL
+	}
+
+	minTTL := maxTTL
+	for _, r := range m.Answer {
+		if r.Header().Ttl < uint32(minTTL.Seconds()) {
+			minTTL = time.Duration(r.Header().Ttl) * time.Second
+		}
+	}
+	for _, r := range m.Ns {
+		if r.Header().Ttl < uint32(minTTL.Seconds()) {
+			minTTL = time.Duration(r.Header().Ttl) * time.Second
+		}
+	}
+
+	for _, r := range m.Extra {
+		if r.Header().Rrtype == dns.TypeOPT {
+			// OPT records use TTL field for extended rcode and flags
+			continue
+		}
+		if r.Header().Ttl < uint32(minTTL.Seconds()) {
+			minTTL = time.Duration(r.Header().Ttl) * time.Second
+		}
+	}
+	return minTTL
+}
+
+func shouldResolve(hostname string) bool {
+	var tld string
+
+	index := strings.LastIndex(hostname, ".")
+	if index == -1 {
+		tld = hostname
+	} else {
+		tld = hostname[index+1:]
+	}
+
+	return tld != "test" && tld != "example" && tld != "invalid" && tld != "localhost"
+}
+
+// GetTLSAPrefix returns the TLSA prefix for the given host:port
+func GetTLSAPrefix(host string) string {
+	h, p, err := net.SplitHostPort(host)
+	if err != nil {
+		return host
+	}
+	return fmt.Sprintf("_%s._tcp.%s", p, h)
+}
diff --git a/resolver_test.go b/resolver_test.go
new file mode 100644
index 0000000..1c4f922
--- /dev/null
+++ b/resolver_test.go
@@ -0,0 +1,89 @@
+package godane
+
+import (
+	"github.com/miekg/dns"
+	"reflect"
+	"sync"
+	"testing"
+)
+
+func TestNewResolver(t *testing.T) {
+	t.Parallel()
+	var wg sync.WaitGroup
+	protos := []string{"udp", "tcp", "tls", "https"}
+	wg.Add(len(protos))
+	for _, p := range protos {
+		go func(proto string) {
+			defer wg.Done()
+
+			rs, err := NewResolver(proto + "://1.1.1.1")
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			ips, err := rs.lookupIPv4("ip.godane.buffrr.dev")
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			if len(ips) == 0 {
+				t.Fatalf("got no ips")
+			}
+		}(p)
+	}
+
+	wg.Wait()
+
+	_, err := NewResolver("udp://:53")
+	if err != nil {
+		t.Fatal(err)
+	}
+}
+
+func TestDNS_LookupIP(t *testing.T) {
+	t.Parallel()
+	rs, err := NewResolver("udp://8.8.8.8")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	ips, err := rs.LookupIP("ip.godane.buffrr.dev")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if len(ips) != 4 {
+		t.Fatalf("want 4 ips, got %d ips", len(ips))
+	}
+
+	_, err = rs.LookupIP("ip.godane.invalid")
+	if err == nil {
+		t.Fatal("want error, got nil")
+	}
+}
+
+var tlsaRRs = []dns.TLSA{
+	{
+		Usage:        3,
+		Selector:     1,
+		MatchingType: 1,
+		Certificate:  "781c71783fcd0d2c4b4b82ae7636fef5d0de94f99ce6192afdf2640357835e0b",
+	},
+}
+
+func TestDNS_LookupTLSA(t *testing.T) {
+	t.Parallel()
+	d, _ := NewResolver("tls://9.9.9.9")
+	r, _ := d.LookupTLSA("tlsa.godane.buffrr.dev")
+
+	if len(r) != 1 {
+		t.Fatalf("want 1, got %d", len(r))
+	}
+
+	r[0].Hdr = tlsaRRs[0].Hdr
+
+	if !reflect.DeepEqual(r[0], tlsaRRs[0]) {
+		t.Fatalf("want %v, got %v", tlsaRRs[0], r[0])
+	}
+
+}
diff --git a/screenshot.png b/screenshot.png
new file mode 100644
index 0000000..399bed4
Binary files /dev/null and b/screenshot.png differ
diff --git a/transport.go b/transport.go
new file mode 100644
index 0000000..e327c27
--- /dev/null
+++ b/transport.go
@@ -0,0 +1,175 @@
+package godane
+
+import (
+	"context"
+	"crypto/tls"
+	"crypto/x509"
+	"errors"
+	"fmt"
+	"github.com/miekg/dns"
+	"net"
+	"net/http"
+	"time"
+)
+
+// Timeouts used in the dialer and http transport.
+const (
+	Timeout               = 30 * time.Second
+	KeepAlive             = 30 * time.Second
+	TLSHandshakeTimeout   = 10 * time.Second
+	ExpectContinueTimeout = time.Second
+)
+
+var dialer = net.Dialer{
+	Timeout:   Timeout,
+	KeepAlive: KeepAlive,
+}
+
+// RoundTripper returns a round tripper capable of performing DANE/TLSA
+// verification. Uses the given resolver for dns lookups.
+func RoundTripper(rs Resolver) http.RoundTripper {
+	return &http.Transport{
+		DialContext: func(ctx context.Context, network, addr string) (conn net.Conn, err error) {
+			return dialContext(ctx, network, addr, rs)
+		},
+		DialTLS: func(network, address string) (net.Conn, error) {
+			tlsa := GetTLSAPrefix(address)
+			if ans, err := rs.LookupTLSA(tlsa); err == nil && TLSASupported(ans) {
+				tlsConfig := newTLSVerifyConfig(ans)
+				return dialTLS(network, address, tlsConfig, rs)
+			}
+
+			return dialTLS(network, address, &tls.Config{InsecureSkipVerify: false}, rs)
+		},
+		TLSHandshakeTimeout:   TLSHandshakeTimeout,
+		ExpectContinueTimeout: ExpectContinueTimeout,
+	}
+
+}
+
+// TLSASupported checks if DANE usage is supported
+// for the given TLSA records. currently checks for usage EE(3).
+func TLSASupported(rrs []dns.TLSA) bool {
+	for _, rr := range rrs {
+		if rr.Usage == 3 {
+			return true
+		}
+	}
+	return false
+}
+
+func newTLSVerifyConfig(rrs []dns.TLSA) *tls.Config {
+	return &tls.Config{
+		InsecureSkipVerify:    true,
+		VerifyPeerCertificate: getTLSAValidator(rrs),
+	}
+}
+
+func getTLSAValidator(rrs []dns.TLSA) func([][]byte, [][]*x509.Certificate) error {
+	return func(rawCerts [][]byte, verifiedChains [][]*x509.Certificate) error {
+		certs := make([]*x509.Certificate, len(rawCerts))
+		for i, asn1Data := range rawCerts {
+			cert, err := x509.ParseCertificate(asn1Data)
+			if err != nil {
+				return errors.New("tls: failed to parse certificate from server: " + err.Error())
+			}
+			certs[i] = cert
+		}
+
+		// TLSA verification.
+		// Currently, supports DANE-EE(3). We only need to check the leaf certificate.
+		// https://tools.ietf.org/id/draft-ietf-dane-ops-02.html#type3
+		// https://tools.ietf.org/html/rfc6698
+		for _, t := range rrs {
+			if t.Usage != 3 {
+				continue
+			}
+
+			if err := t.Verify(certs[0]); err == nil {
+				return nil
+			}
+		}
+
+		return errors.New("tls: DANE verification failed")
+	}
+}
+
+// GetDialFunc returns a dial function that uses the given resolver.
+func GetDialFunc(rs Resolver) func(network string, addr string) (net.Conn, error) {
+	return func(network string, addr string) (net.Conn, error) {
+		_, port, ips, err := readAddr(addr, rs)
+		if err != nil {
+			return nil, err
+		}
+
+		for _, ip := range ips {
+			ipaddr := net.JoinHostPort(ip.String(), port)
+			conn, err := dialer.Dial(network, ipaddr)
+			if err != nil {
+				continue
+			}
+			return conn, nil
+		}
+		return nil, fmt.Errorf("dial: could not reach %s", addr)
+	}
+}
+
+func dialContext(ctx context.Context, network, addr string, rs Resolver) (net.Conn, error) {
+	_, port, ips, err := readAddr(addr, rs)
+	if err != nil {
+		return nil, err
+	}
+
+	for _, ip := range ips {
+		ipaddr := net.JoinHostPort(ip.String(), port)
+		conn, err := dialer.DialContext(ctx, network, ipaddr)
+		if err != nil {
+			continue
+		}
+		return conn, nil
+	}
+
+	return nil, fmt.Errorf("dial ctx: could not reach %s", addr)
+
+}
+
+func dialTLS(network, addr string, config *tls.Config, rs Resolver) (*tls.Conn, error) {
+	host, port, ips, err := readAddr(addr, rs)
+	if err != nil {
+		return nil, err
+	}
+
+	config.ServerName = host
+
+	for _, ip := range ips {
+		ipaddr := net.JoinHostPort(ip.String(), port)
+		conn, err := tls.Dial(network, ipaddr, config)
+		if err != nil {
+			continue
+		}
+		return conn, nil
+	}
+
+	return nil, fmt.Errorf("dial tls: could not reach %s", addr)
+
+}
+
+func readAddr(addr string, rs Resolver) (host, port string, ips []net.IP, err error) {
+	host, port, err = net.SplitHostPort(addr)
+	if err != nil {
+		return
+	}
+
+	ips, err = rs.LookupIP(host)
+	if err != nil {
+		err = fmt.Errorf("dial: %v", err)
+		return
+	}
+
+	if len(ips) == 0 {
+		err = fmt.Errorf("dial: lookup %s no such host", addr)
+		return
+	}
+
+	return
+}
diff --git a/transport_test.go b/transport_test.go
new file mode 100644
index 0000000..e92f0e5
--- /dev/null
+++ b/transport_test.go
@@ -0,0 +1,208 @@
+package godane
+
+import (
+	"bytes"
+	"crypto/rsa"
+	"crypto/tls"
+	"crypto/x509"
+	"encoding/pem"
+	"errors"
+	"fmt"
+	"github.com/google/martian/v3/mitm"
+	"github.com/miekg/dns"
+	"io/ioutil"
+	"log"
+	"net"
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"strings"
+	"testing"
+	"time"
+)
+
+type TestResolver struct {
+	domain    string
+	ip        net.IP
+	tlsaPrefx string
+	tlsaRRs   []dns.TLSA
+}
+
+func (rs TestResolver) LookupIP(name string) ([]net.IP, error) {
+	if name == rs.domain {
+		return []net.IP{rs.ip}, nil
+	}
+
+	return nil, errors.New("no such host")
+}
+
+func (rs TestResolver) LookupTLSA(prefix string) ([]dns.TLSA, error) {
+	if prefix == rs.tlsaPrefx {
+		return rs.tlsaRRs, nil
+	}
+
+	return nil, errors.New("not found")
+}
+
+func TestRoundTripperTLS(t *testing.T) {
+	ts := httptest.NewUnstartedServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		fmt.Fprintln(w, "hello")
+	}))
+	defer ts.Close()
+	cert, _, goodTLSA := testCreateCertTLSAPair(3, 1, 1)
+	ts.TLS = &tls.Config{
+		Certificates: []tls.Certificate{cert},
+	}
+
+	ts.StartTLS()
+
+	// https://127.0.0.1:port => https://example.com:port
+	url, _ := url.Parse(ts.URL)
+	host, port, _ := net.SplitHostPort(url.Host)
+	addr := net.JoinHostPort("example.com", port)
+	requrl := "https://" + addr
+
+	rs := TestResolver{
+		domain: "example.com",
+		ip:     net.ParseIP(host),
+	}
+
+	client := ts.Client()
+	client.Transport = RoundTripper(rs)
+
+	// no tlsa
+	_, err := client.Get(requrl)
+	if err == nil {
+		t.Fatalf("want error, got nil")
+	}
+
+	// tlsa doesn't match server certificate
+	rs.tlsaPrefx = GetTLSAPrefix(addr)
+	_, _, tlsa2 := testCreateCertTLSAPair(3, 1, 1)
+	rs.tlsaRRs = []dns.TLSA{tlsa2}
+
+	client.Transport = RoundTripper(rs)
+	_, err = client.Get(requrl)
+	if err == nil {
+		t.Fatalf("want error, got nil")
+	}
+
+	// good tlsa
+	rs.tlsaRRs = []dns.TLSA{goodTLSA}
+	client.Transport = RoundTripper(rs)
+	res, err := client.Get(requrl)
+
+	if err != nil {
+		t.Fatal(err)
+	}
+	greeting, err := ioutil.ReadAll(res.Body)
+	res.Body.Close()
+
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	got := strings.TrimSpace(string(greeting))
+
+	if got != "hello" {
+		t.Fatalf("want `hello`, got `%s`", got)
+	}
+
+	// unsupported tlsa
+	_, _, tlsa3 := testCreateCertTLSAPair(1, 0, 1)
+	rs.tlsaRRs = []dns.TLSA{tlsa3}
+	client.Transport = RoundTripper(rs)
+	_, err = client.Get(requrl)
+
+	if err == nil {
+		t.Fatalf("want error, got nil")
+	}
+}
+
+func TestRoundTripperNoTLS(t *testing.T) {
+	ts := httptest.NewServer(http.HandlerFunc(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		fmt.Fprintln(w, "hello")
+	})))
+	defer ts.Close()
+
+	// http://127.0.0.1:port => http://example.com:port
+	url, _ := url.Parse(ts.URL)
+	host, port, _ := net.SplitHostPort(url.Host)
+	addr := net.JoinHostPort("example.com", port)
+	requrl := "http://" + addr
+
+	rs := TestResolver{
+		domain: "example.com",
+		ip:     net.ParseIP(host),
+	}
+
+	client := ts.Client()
+	client.Transport = RoundTripper(rs)
+
+	res, err := client.Get(requrl)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	greeting, err := ioutil.ReadAll(res.Body)
+	res.Body.Close()
+
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	got := strings.TrimSpace(string(greeting))
+
+	if got != "hello" {
+		t.Fatalf("want `hello`, got `%s`", got)
+	}
+}
+
+// creates a test certificate and a TLSA record for it.
+func testCreateCertTLSAPair(usage, selector, matching uint8) (tls.Certificate, *rsa.PrivateKey, dns.TLSA) {
+	ca, priv, err := mitm.NewAuthority("DNSSEC", "DNSSEC", time.Hour)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	m, err := mitm.NewConfig(ca, priv)
+	if err != nil {
+		log.Fatal(err)
+	}
+	mc := m.TLS()
+	cert, err := mc.GetCertificate(&tls.ClientHelloInfo{
+		ServerName: "example.com",
+	})
+
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	if cert == nil {
+		log.Fatal("no cert")
+	}
+
+	certStr, err := dns.CertificateToDANE(selector, matching, cert.Leaf)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	tlsa := dns.TLSA{
+		Usage:        usage,
+		Selector:     selector,
+		MatchingType: matching,
+		Certificate:  certStr,
+	}
+
+	return *cert, priv, tlsa
+}
+
+func printCA(ca *x509.Certificate) {
+	raw := bytes.NewBuffer(make([]byte, 8000))
+	pem.Encode(raw, &pem.Block{
+		Type:  "CERTIFICATE",
+		Bytes: ca.Raw,
+	})
+
+	fmt.Println(raw.String())
+}