initial work on openpgp key

src/routes/shorturl.go

@@ -2,13 +2,21 @@ package routes
 
 import (
 	"bytes"
+	"crypto/sha1"
 	"encoding/json"
+	"fmt"
+	"io"
 	"net/http"
+	"net/mail"
 	"net/url"
 	"regexp"
+	"strings"
 
 	"github.com/coreos/bbolt"
 	"github.com/gorilla/mux"
+	"github.com/sour-is/crypto/openpgp"
+	"github.com/tv42/zbase32"
+
 	"sour.is/x/toolbox/httpsrv"
 	"sour.is/x/toolbox/log"
 	"sour.is/x/toolbox/uuid"
@@ -21,6 +29,7 @@ func init() {
 	httpsrv.HttpRegister("short", httpsrv.HttpRoutes{
 		{Name: "getShort", Method: "GET", Pattern: "/s/{id}", HandlerFunc: s.getShort},
 		{Name: "putShort", Method: "PUT", Pattern: "/s/{id}", HandlerFunc: s.putShort},
+		{Name: "getIdentity", Method: "GET", Pattern: "/id/{id}", HandlerFunc: s.getIdentity},
 	})
 }
 
@@ -190,3 +199,101 @@ func (s *shortDB) PutURL(id string, url *shortURL) {
 		log.Errorf("ShortURL: failed to write db at [%s]", s.path)
 	}
 }
+
+func (s *shortDB) getIdentity(w http.ResponseWriter, r *http.Request) {
+	vars := mux.Vars(r)
+
+	id := vars["id"]
+
+	useArmored := false
+	addr := ""
+
+	if isFingerprint(id) {
+		addr = "https://keys.openpgp.org/vks/v1/by-fingerprint/" + strings.ToUpper(id)
+		useArmored = true
+	} else if email, err := mail.ParseAddress(id); err == nil {
+		addr = getWKDPubKeyAddr(email)
+		useArmored = false
+	} else {
+		httpsrv.WriteError(w, 400, err.Error())
+		return
+	}
+
+	resp, err := http.Get(addr)
+	if err != nil {
+		print(err)
+	}
+
+	defer resp.Body.Close()
+
+	if resp.Header.Get("Content-Type") == "application/pgp-keys" {
+		useArmored = true
+	}
+	log.Infos("getIdentity", "id", id, "useArmored", useArmored, "status", resp.Status, "addr", addr)
+
+	var lis openpgp.EntityList
+	if useArmored {
+		lis, err = openpgp.ReadArmoredKeyRing(resp.Body)
+	} else {
+		lis, err = openpgp.ReadKeyRing(resp.Body)
+	}
+	if err != nil {
+		fmt.Println(err)
+		httpsrv.WriteError(w, 400, "bad decode")
+		return
+	}
+
+	for _, entity := range lis {
+		entityString(w, entity)
+	}
+}
+
+func isFingerprint(s string) bool {
+	for _, r := range s {
+		switch r {
+		case '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f', 'A', 'B', 'C', 'D', 'E', 'F':
+		default:
+			return false
+		}
+	}
+
+	return true
+}
+
+func entityString(out io.Writer, e *openpgp.Entity) {
+	if e == nil {
+		return
+	}
+
+	if e.Identities != nil {
+		fmt.Fprintln(out, "Identities:")
+		for name, identity := range e.Identities {
+			fmt.Fprintf(out, "  %s:\n", name)
+			identityString(out, identity)
+			fmt.Fprintln(out)
+		}
+	}
+}
+
+func identityString(out io.Writer, i *openpgp.Identity) {
+	if i == nil || i.SelfSignature == nil {
+		return
+	}
+
+	fmt.Fprintf(out, "name: %s\n", i.Name)
+
+	for key, valueList := range i.SelfSignature.NotationData {
+		for _, value := range valueList {
+			fmt.Fprintln(out, "    ", key, value)
+		}
+	}
+}
+
+func getWKDPubKeyAddr(email *mail.Address) string {
+	parts := strings.SplitN(email.Address, "@", 2)
+
+	hash := sha1.Sum([]byte(parts[0]))
+	lp := zbase32.EncodeToString(hash[:])
+
+	return fmt.Sprintf("https://%s/.well-known/openpgpkey/hu/%s", parts[1], lp)
+}