Add support for DNS stamps and for DNSCrypt servers

This allows connections to DoH servers using their stamp, and adds
support for DNSCrypt servers by the way.

README.md

@@ -12,7 +12,7 @@
 
 ---
 
-**doggo** is a modern command-line DNS client (like _dig_) written in Golang. It outputs information in a neat concise manner and supports protocols like DoH, DoT as well.
+**doggo** is a modern command-line DNS client (like _dig_) written in Golang. It outputs information in a neat concise manner and supports protocols like DoH, DoT and DNSCrypt as well.
 
 It's totally inspired from [dog](https://github.com/ogham/dog/) which is written in Rust. I wanted to add some features to it but since I don't know Rust, I found it as a nice opportunity
 to experiment with writing a DNS Client from scratch in `Go` myself. Hence the name `dog` +`go` => **doggo**.
@@ -195,6 +195,8 @@ URL scheme of the server is used to identify which resolver to use for lookups.
   @tcp://        eg: @1.1.1.1 initiates a TCP resolver for 1.1.1.1:53.
   @https://      eg: @https://cloudflare-dns.com/dns-query initiates a DOH resolver for Cloudflare DoH server.
   @tls://        eg: @1.1.1.1 initiates a DoT resolver for 1.1.1.1:853.
+  @sdns://       eg: @sdns://AgcAAAAAAAAABzEuMC4wLjEAEmRucy5jbG91ZGZsYXJlLmNvbQovZG5zLXF1ZXJ5
+                 initiates a DNSCrypt or DoH resolver using its DNS stamp
 ```
 
 ### Query Options

cmd/doggo/cli/help.go

@@ -36,6 +36,7 @@ var appHelpTextTemplate = `{{ "NAME" | color "" "heading" }}:
   {{"@tcp://" | color "yellow" ""}}        eg: @tcp://1.1.1.1 initiates a {{"TCP" | color "cyan" ""}} resolver for 1.1.1.1:53.
   {{"@https://" | color "yellow" ""}}      eg: @https://cloudflare-dns.com/dns-query initiates a {{"DOH" | color "cyan" ""}} resolver for Cloudflare DoH server.
   {{"@tls://" | color "yellow" ""}}        eg: @tls://1.1.1.1 initiates a {{"DoT" | color "cyan" ""}} resolver for 1.1.1.1:853.
+  {{"@sdns://" | color "yellow" ""}}       initiates a {{"DNSCrypt" | color "cyan" ""}} or {{"DoH" | color "cyan" ""}} resolver using its DNS stamp.
 
 {{ "Query Options" | color "" "heading" }}:
   {{"-q, --query=HOSTNAME" | color "yellow" ""}}        Hostname to query the DNS records for (eg {{"mrkaran.dev" | color "cyan" ""}}).

completions/doggo.fish

@@ -12,7 +12,7 @@ complete -c doggo -s 'n' -l 'nameserver' -d "Address of a specific nameserver to
 complete -c doggo -s 'c' -l 'class'      -d "Network class of the DNS record being queried" -x -a "IN CH HS"
 
 # Transport options
-complete -c doggo -x -a "@udp:// @tcp:// @https:// @tls://"          -d "Select the protocol for resolving queries"
+complete -c doggo -x -a "@udp:// @tcp:// @https:// @tls:// @sdns://"          -d "Select the protocol for resolving queries"
 
 # Resolver options
 complete -c doggo -l 'ndots'             -d "Specify ndots parameter. Takes value from /etc/resolv.conf if using the system namesever or 1 otherwise"

go.mod

@@ -3,9 +3,10 @@ module github.com/mr-karan/doggo
 go 1.16
 
 require (
+	github.com/ameshkov/dnscrypt v1.1.0
+	github.com/ameshkov/dnsstamps v1.0.3
 	github.com/fatih/color v1.10.0
 	github.com/go-chi/chi v1.5.3
-	github.com/go-chi/render v1.0.1
 	github.com/knadh/koanf v0.14.0
 	github.com/mattn/go-runewidth v0.0.9 // indirect
 	github.com/miekg/dns v1.1.35

go.sum

@@ -1,4 +1,14 @@
+github.com/BurntSushi/toml v0.3.1 h1:WXkYYl6Yr3qBf1K79EBnL4mak0OimBfB0XUf9Vl28OQ=
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
+github.com/aead/chacha20 v0.0.0-20180709150244-8b13a72661da h1:KjTM2ks9d14ZYCvmHS9iAKVt9AyzRSqNU1qabPih5BY=
+github.com/aead/chacha20 v0.0.0-20180709150244-8b13a72661da/go.mod h1:eHEWzANqSiWQsof+nXEI9bUVUyV6F53Fp89EuCh2EAA=
+github.com/aead/poly1305 v0.0.0-20180717145839-3fee0db0b635 h1:52m0LGchQBBVqJRyYYufQuIbVqRawmubW3OFGqK1ekw=
+github.com/aead/poly1305 v0.0.0-20180717145839-3fee0db0b635/go.mod h1:lmLxL+FV291OopO93Bwf9fQLQeLyt33VJRUg5VJ30us=
+github.com/ameshkov/dnscrypt v1.1.0 h1:2vAt5dD6ZmqlAxEAfzRcLBnkvdf8NI46Kn9InSwQbSI=
+github.com/ameshkov/dnscrypt v1.1.0/go.mod h1:ikduAxNLCTEfd1AaCgpIA5TgroIVQ8JY3Vb095fiFJg=
+github.com/ameshkov/dnsstamps v1.0.1/go.mod h1:Ii3eUu73dx4Vw5O4wjzmT5+lkCwovjzaEZZ4gKyIH5A=
+github.com/ameshkov/dnsstamps v1.0.3 h1:Srzik+J9mivH1alRACTbys2xOxs0lRH9qnTA7Y1OYVo=
+github.com/ameshkov/dnsstamps v1.0.3/go.mod h1:Ii3eUu73dx4Vw5O4wjzmT5+lkCwovjzaEZZ4gKyIH5A=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
@@ -9,8 +19,6 @@ github.com/fsnotify/fsnotify v1.4.9 h1:hsms1Qyu0jgnwNXIxa+/V/PDsU6CfLf6CNO8H7IWo
 github.com/fsnotify/fsnotify v1.4.9/go.mod h1:znqG4EE+3YCdAaPaxE2ZRY/06pZUdp0tY4IgpuI1SZQ=
 github.com/go-chi/chi v1.5.3 h1:+DVDS9/D3MTbEu3WrrH3oz9oP6PlSPSNj8LLw3X17yU=
 github.com/go-chi/chi v1.5.3/go.mod h1:Q8xfe6s3fjZyMr8ZTv5jL+vxhVaFyCq2s+RvSfzTD0E=
-github.com/go-chi/render v1.0.1 h1:4/5tis2cKaNdnv9zFLfXzcquC9HbeZgCnxGnKrltBS8=
-github.com/go-chi/render v1.0.1/go.mod h1:pq4Rr7HbnsdaeHagklXub+p6Wd16Af5l9koip1OvJns=
 github.com/hashicorp/hcl v1.0.0 h1:0Anlzjpi4vEasTeNFn2mLJgTSwt0+6sfsiTG8qcWGx4=
 github.com/hashicorp/hcl v1.0.0/go.mod h1:E5yfLk+7swimpb2L/Alb/PJmXilQ/rhwaUYs4T20WEQ=
 github.com/joho/godotenv v1.3.0 h1:Zjp+RcGpHhGlrMbJzXTrZZPrWj+1vfm90La1wgB6Bhc=
@@ -24,6 +32,7 @@ github.com/mattn/go-isatty v0.0.12/go.mod h1:cbi8OIDigv2wuxKPP5vlRcQ1OAZbq2CE4Ky
 github.com/mattn/go-runewidth v0.0.7/go.mod h1:H031xJmbD/WCDINGzjvQ9THkh0rPKHF+m2gUSrubnMI=
 github.com/mattn/go-runewidth v0.0.9 h1:Lm995f3rfxdpd6TSmuVCHVb/QhupuXlYr8sCI/QdE+0=
 github.com/mattn/go-runewidth v0.0.9/go.mod h1:H031xJmbD/WCDINGzjvQ9THkh0rPKHF+m2gUSrubnMI=
+github.com/miekg/dns v1.1.29/go.mod h1:KNUDUusw/aVsxyTYZM1oqvCicbwhgbNgztCETuNZ7xM=
 github.com/miekg/dns v1.1.35 h1:oTfOaDH+mZkdcgdIjH6yBajRGtIwcwcaR+rt23ZSrJs=
 github.com/miekg/dns v1.1.35/go.mod h1:KNUDUusw/aVsxyTYZM1oqvCicbwhgbNgztCETuNZ7xM=
 github.com/mitchellh/mapstructure v1.2.2 h1:dxe5oCinTXiTIcfgmZecdCzPmAJKd46KsCWc35r0TV4=
@@ -45,13 +54,15 @@ github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UV
 github.com/stretchr/testify v1.6.1 h1:hDPOHmpOpP40lSULcqw7IrRb/u7w6RpDC9399XyoNd0=
 github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 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/crypto v0.0.0-20200323165209-0ec3e9974c59 h1:3zb4D3T4G8jdExgVU/95+vQXfpEPiMdCaZgmGVxjNHM=
+golang.org/x/crypto v0.0.0-20200323165209-0ec3e9974c59/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 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 v0.0.0-20190923162816-aa69164e4478 h1:l5EDrHhldLYb3ZRHDUhXF7Om7MvYXnkV9/iQNo1lX6g=
 golang.org/x/net v0.0.0-20190923162816-aa69164e4478/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/net v0.0.0-20200324143707-d3edc9973b7e h1:3G+cUijn7XD+S4eJFddp53Pv7+slrESplyjG25HgL+k=
+golang.org/x/net v0.0.0-20200324143707-d3edc9973b7e/go.mod h1:qpuaurCH72eLCgpAm/N6yyVIVM9cpaDIP3A8BGJEC5A=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58 h1:8gQV6CLnAEikrhgkHFbMAEhagSSnXWGV915qUMm9mrU=
 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=
@@ -61,6 +72,7 @@ golang.org/x/sys v0.0.0-20191005200804-aed5e4c7ecf9/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20191026070338-33540a1f6037/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200116001909-b77594299b42/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200223170610-d5e6a3e2c0ae/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200331124033-c3d80250170d h1:nc5K6ox/4lTFbMVSL9WRR81ixkcwXThoiF6yf+R9scA=
 golang.org/x/sys v0.0.0-20200331124033-c3d80250170d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=

internal/app/nameservers.go

@@ -5,6 +5,7 @@ import (
 	"net"
 	"net/url"
 
+	"github.com/ameshkov/dnsstamps"
 	"github.com/mr-karan/doggo/pkg/config"
 	"github.com/mr-karan/doggo/pkg/models"
 )
@@ -60,6 +61,23 @@ func initNameserver(n string) (models.Nameserver, error) {
 	if err != nil {
 		return ns, err
 	}
+	if u.Scheme == "sdns" {
+		stamp, err := dnsstamps.NewServerStampFromString(n)
+		if err != nil {
+			return ns, err
+		}
+		switch stamp.Proto {
+		case dnsstamps.StampProtoTypeDoH:
+			ns.Type = models.DOHResolver
+			address := url.URL{Scheme: "https", Host: stamp.ProviderName, Path: stamp.Path}
+			ns.Address = address.String()
+		case dnsstamps.StampProtoTypeDNSCrypt:
+			ns.Type = models.DNSCryptResolver
+			ns.Address = n
+		default:
+			return ns, fmt.Errorf("unsupported protocol: %v", stamp.Proto.String())
+		}
+	}
 	if u.Scheme == "https" {
 		ns.Type = models.DOHResolver
 		ns.Address = u.String()

pkg/models/models.go

@@ -13,6 +13,7 @@ const (
 	DOHResolver      = "doh"
 	TCPResolver      = "tcp"
 	DOTResolver      = "dot"
+	DNSCryptResolver = "dnscrypt"
 )
 
 // QueryFlags is used store the query params

pkg/resolvers/dnscrypt.go

@@ -0,0 +1,81 @@
+package resolvers
+
+import (
+	"github.com/ameshkov/dnscrypt"
+	"github.com/miekg/dns"
+	"github.com/sirupsen/logrus"
+)
+
+// DNSCryptResolver represents the config options for setting up a Resolver.
+type DNSCryptResolver struct {
+	client          *dnscrypt.Client
+	serverInfo      *dnscrypt.ServerInfo
+	server          string
+	resolverOptions Options
+}
+
+// DNSCryptResolverOpts holds options for setting up a DNSCrypt resolver.
+type DNSCryptResolverOpts struct {
+	IPv4Only bool
+	IPv6Only bool
+	UseTLS   bool
+	UseTCP   bool
+}
+
+// NewDNSCryptResolver accepts a list of nameservers and configures a DNS resolver.
+func NewDNSCryptResolver(server string, dnscryptOpts DNSCryptResolverOpts, resolverOpts Options) (Resolver, error) {
+	net := "udp"
+	if dnscryptOpts.UseTCP {
+		net = "tcp"
+	}
+	client := &dnscrypt.Client{Proto: net, AdjustPayloadSize: true}
+	serverInfo, _, err := client.Dial(server)
+	if err != nil {
+		return nil, err
+	}
+	return &DNSCryptResolver{
+		client:          client,
+		serverInfo:      serverInfo,
+		server:          server,
+		resolverOptions: resolverOpts,
+	}, nil
+}
+
+// Lookup takes a dns.Question and sends them to DNS Server.
+// It parses the Response from the server in a custom output format.
+func (r *DNSCryptResolver) Lookup(question dns.Question) (Response, error) {
+	var (
+		rsp      Response
+		messages = prepareMessages(question, r.resolverOptions.Ndots, r.resolverOptions.SearchList)
+	)
+	for _, msg := range messages {
+		r.resolverOptions.Logger.WithFields(logrus.Fields{
+			"domain":     msg.Question[0].Name,
+			"ndots":      r.resolverOptions.Ndots,
+			"nameserver": r.serverInfo.ProviderName,
+		}).Debug("Attempting to resolve")
+		in, rtt, err := r.client.Exchange(&msg, r.serverInfo)
+		if err != nil {
+			return rsp, err
+		}
+		// pack questions in output.
+		for _, q := range msg.Question {
+			ques := Question{
+				Name:  q.Name,
+				Class: dns.ClassToString[q.Qclass],
+				Type:  dns.TypeToString[q.Qtype],
+			}
+			rsp.Questions = append(rsp.Questions, ques)
+		}
+		// get the authorities and answers.
+		output := parseMessage(in, rtt, r.server)
+		rsp.Authorities = output.Authorities
+		rsp.Answers = output.Answers
+
+		if len(output.Answers) > 0 {
+			// stop iterating the searchlist.
+			break
+		}
+	}
+	return rsp, nil
+}

pkg/resolvers/resolver.go

@@ -127,6 +127,17 @@ func LoadResolvers(opts Options) ([]Resolver, error) {
 			}
 			rslvrs = append(rslvrs, rslvr)
 		}
+		if ns.Type == models.DNSCryptResolver {
+			opts.Logger.Debug("initiating DNSCrypt resolver")
+			rslvr, err := NewDNSCryptResolver(ns.Address,
+				DNSCryptResolverOpts{
+					UseTCP: false,
+				}, resolverOpts)
+			if err != nil {
+				return rslvrs, err
+			}
+			rslvrs = append(rslvrs, rslvr)
+		}
 	}
 	return rslvrs, nil
 }