From d25294add79f9ef5a14262bf391b9aeb4e673ca5 Mon Sep 17 00:00:00 2001
From: Martin Dosch <martin@mdosch.de>
Date: Mon, 18 Apr 2022 17:14:03 +0200
Subject: [PATCH] Ox: Cache public keys.

---
 ox.go | 70 ++++++++++++++++++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 65 insertions(+), 5 deletions(-)

diff --git a/ox.go b/ox.go
index 10575d4..b576459 100644
--- a/ox.go
+++ b/ox.go
@@ -57,7 +57,7 @@ func oxImportPrivKey(jid string, privKeyLocation string, client *xmpp.Client) er
 	if err != nil {
 		return err
 	}
-	err = oxStorePrivKey(location,
+	err = oxStoreKey(location,
 		base64.StdEncoding.EncodeToString(keySerialized))
 	if err != nil {
 		log.Fatal(err)
@@ -98,6 +98,39 @@ func oxGetPrivKeyLoc(jid string) (string, error) {
 	return dataFile, nil
 }
 
+func oxGetPubKeyLoc(fingerprint string) (string, error) {
+	var err error
+	var homeDir, dataDir string
+	switch {
+	case os.Getenv("$XDG_DATA_HOME") != "":
+		dataDir = os.Getenv("$XDG_DATA_HOME")
+	case os.Getenv("$XDG_HOME") != "":
+		homeDir = os.Getenv("$XDG_HOME")
+		dataDir = homeDir + "/.local/share"
+	case os.Getenv("$HOME") != "":
+		homeDir = os.Getenv("$HOME")
+		dataDir = homeDir + "/.local/share"
+	default:
+		homeDir, err = os.UserHomeDir()
+		if err != nil {
+			return "error", err
+		}
+		if homeDir == "" {
+			return "error", err
+		}
+		dataDir = homeDir + "/.local/share"
+	}
+	dataDir = dataDir + "/go-sendxmpp/oxpubkeys/"
+	if _, err = os.Stat(dataDir); os.IsNotExist(err) {
+		err = os.MkdirAll(dataDir, 0700)
+		if err != nil {
+			return "error", err
+		}
+	}
+	dataFile := dataDir + fingerprint
+	return dataFile, nil
+}
+
 func oxGetPrivKey(jid string, passphrase string) (*crypto.Key, error) {
 	dataFile, err := oxGetPrivKeyLoc(jid)
 	if err != nil {
@@ -135,7 +168,7 @@ func oxGetPrivKey(jid string, passphrase string) (*crypto.Key, error) {
 	return key, nil
 }
 
-func oxStorePrivKey(location string, privKey string) error {
+func oxStoreKey(location string, key string) error {
 	var file *os.File
 	if _, err := os.Stat(location); os.IsNotExist(err) {
 		file, err = os.Create(location)
@@ -154,7 +187,7 @@ func oxStorePrivKey(location string, privKey string) error {
 	} else {
 		_ = file.Chmod(os.FileMode(0200))
 	}
-	_, err := file.Write([]byte(privKey))
+	_, err := file.Write([]byte(key))
 	if err != nil {
 		return err
 	}
@@ -187,7 +220,7 @@ func oxGenPrivKey(jid string, client *xmpp.Client, passphrase string) error {
 	if err != nil {
 		return err
 	}
-	err = oxStorePrivKey(location,
+	err = oxStoreKey(location,
 		base64.StdEncoding.EncodeToString(keySerialized))
 	if err != nil {
 		log.Fatal(err)
@@ -325,6 +358,7 @@ func oxRecvPublicKey(client *xmpp.Client, recipient string,
 func oxGetPublicKey(client *xmpp.Client, recipient string) (*crypto.Key, error) {
 	var oxPublicKeyListRequest IQPubsubRequest
 	var oxPublicKeyListXML OxPublicKeysList
+
 	oxPublicKeyListRequest.Xmlns = nsPubsub
 	oxPublicKeyListRequest.Items.Node = nsOxPubKeys
 	oxPublicKeyListRequest.Items.MaxItems = "1"
@@ -364,11 +398,37 @@ func oxGetPublicKey(client *xmpp.Client, recipient string) (*crypto.Key, error)
 		return nil, errors.New("server didn't provide public key fingerprints for " + recipient)
 	}
 
+	pubKeyLocation, err := oxGetPubKeyLoc(fingerprint)
+	if err != nil {
+		return nil, err
+	}
+	pubKeyFile, err := readFile(pubKeyLocation)
+	if err == nil {
+		decodedPubKey, err := base64.StdEncoding.DecodeString(pubKeyFile.String())
+		if err != nil {
+			return nil, err
+		}
+		key, err := crypto.NewKey(decodedPubKey)
+		if err != nil {
+			return nil, err
+		}
+		if !key.IsExpired() {
+			return key, nil
+		}
+	}
 	key, err := oxRecvPublicKey(client, recipient, fingerprint)
 	if err != nil {
 		return nil, errors.New("Couldn't fetch public key.")
 	}
-
+	keySerialized, err := key.Serialize()
+	if err != nil {
+		return nil, err
+	}
+	err = oxStoreKey(pubKeyLocation,
+		base64.StdEncoding.EncodeToString(keySerialized))
+	if err != nil {
+		log.Println(err)
+	}
 	return key, nil
 }