diff options
Diffstat (limited to 'plugins/openpgp/src/xmpp_module.vala')
| -rw-r--r-- | plugins/openpgp/src/xmpp_module.vala | 154 |
1 files changed, 154 insertions, 0 deletions
diff --git a/plugins/openpgp/src/xmpp_module.vala b/plugins/openpgp/src/xmpp_module.vala new file mode 100644 index 00000000..440be5f1 --- /dev/null +++ b/plugins/openpgp/src/xmpp_module.vala @@ -0,0 +1,154 @@ +using GPG; + +using Xmpp; +using Xmpp.Core; + +namespace Dino.Plugins.OpenPgp { + private const string NS_URI = "jabber:x"; + private const string NS_URI_ENCRYPTED = NS_URI + ":encrypted"; + private const string NS_URI_SIGNED = NS_URI + ":signed"; + + public class Module : XmppStreamModule { + public const string ID = "0027_current_pgp_usage"; + public static ModuleIdentity<Module> IDENTITY = new ModuleIdentity<Module>(NS_URI, ID); + + public signal void received_jid_key_id(XmppStream stream, string jid, string key_id); + + private string? signed_status; + private string? own_key_id; + + public Module() { + signed_status = gpg_sign(""); + if (signed_status != null) own_key_id = gpg_verify(signed_status, ""); + } + + public bool encrypt(Message.Stanza message, string key_id) { + string? enc_body = gpg_encrypt(message.body, new string[] {key_id, own_key_id}); + if (enc_body != null) { + message.stanza.put_node(new StanzaNode.build("x", NS_URI_ENCRYPTED).add_self_xmlns().put_node(new StanzaNode.text(enc_body))); + message.body = "[This message is OpenPGP encrypted (see XEP-0027)]"; + return true; + } + return false; + } + + public string? get_cyphertext(Message.Stanza message) { + StanzaNode? x_node = message.stanza.get_subnode("x", NS_URI_ENCRYPTED); + return x_node == null ? null : x_node.get_string_content(); + } + + public override void attach(XmppStream stream) { + Presence.Module.require(stream); + stream.get_module(Presence.Module.IDENTITY).received_presence.connect(on_received_presence); + stream.get_module(Presence.Module.IDENTITY).pre_send_presence_stanza.connect(on_pre_send_presence_stanza); + Message.Module.require(stream); + stream.get_module(Message.Module.IDENTITY).pre_received_message.connect(on_pre_received_message); + stream.add_flag(new Flag()); + } + + public override void detach(XmppStream stream) { + stream.get_module(Presence.Module.IDENTITY).received_presence.disconnect(on_received_presence); + stream.get_module(Presence.Module.IDENTITY).pre_send_presence_stanza.disconnect(on_pre_send_presence_stanza); + stream.get_module(Message.Module.IDENTITY).pre_received_message.disconnect(on_pre_received_message); + } + + public static void require(XmppStream stream) { + if (stream.get_module(IDENTITY) == null) stream.add_module(new Module()); + } + + public override string get_ns() { return NS_URI; } + public override string get_id() { return ID; } + + private void on_received_presence(XmppStream stream, Presence.Stanza presence) { + StanzaNode x_node = presence.stanza.get_subnode("x", NS_URI_SIGNED); + if (x_node != null) { + string? sig = x_node.get_string_content(); + if (sig != null) { + string signed_data = presence.status == null ? "" : presence.status; + string? key_id = gpg_verify(sig, signed_data); + if (key_id != null) { + Flag.get_flag(stream).set_key_id(presence.from, key_id); + received_jid_key_id(stream, presence.from, key_id); + } + } + } + } + + private void on_pre_send_presence_stanza(XmppStream stream, Presence.Stanza presence) { + if (presence.type_ == Presence.Stanza.TYPE_AVAILABLE && signed_status != null) { + presence.stanza.put_node(new StanzaNode.build("x", NS_URI_SIGNED).add_self_xmlns().put_node(new StanzaNode.text(signed_status))); + } + } + + private void on_pre_received_message(XmppStream stream, Message.Stanza message) { + string? encrypted = get_cyphertext(message); + if (encrypted != null) { + MessageFlag flag = new MessageFlag(); + message.add_flag(flag); + string? decrypted = gpg_decrypt(encrypted); + if (decrypted != null) { + flag.decrypted = true; + message.body = decrypted; + } + } + } + + private static string? gpg_encrypt(string plain, string[] key_ids) { + GPG.Key[] keys = new GPG.Key[key_ids.length]; + string encr; + try { + for (int i = 0; i < key_ids.length; i++) { + keys[i] = GPGHelper.get_public_key(key_ids[i]); + } + encr = GPGHelper.encrypt_armor(plain, keys, GPG.EncryptFlags.ALWAYS_TRUST); + } catch (Error e) { + return null; + } + int encryption_start = encr.index_of("\n\n") + 2; + return encr.substring(encryption_start, encr.length - "\n-----END PGP MESSAGE-----".length - encryption_start); + } + + private static string? gpg_decrypt(string enc) { + string armor = "-----BEGIN PGP MESSAGE-----\n\n" + enc + "\n-----END PGP MESSAGE-----"; + string? decr = null; + try { + decr = GPGHelper.decrypt(armor); + } catch (Error e) { } + return decr; + } + + private static string? gpg_verify(string sig, string signed_text) { + string armor = "-----BEGIN PGP MESSAGE-----\n\n" + sig + "\n-----END PGP MESSAGE-----"; + string? sign_key = null; + try { + sign_key = GPGHelper.get_sign_key(armor, signed_text); + } catch (Error e) { } + return sign_key; + } + + private static string? gpg_sign(string str) { + string signed; + try { + signed = GPGHelper.sign(str, GPG.SigMode.CLEAR); + } catch (Error e) { + return null; + } + int signature_start = signed.index_of("-----BEGIN PGP SIGNATURE-----"); + signature_start = signed.index_of("\n\n", signature_start) + 2; + return signed.substring(signature_start, signed.length - "\n-----END PGP SIGNATURE-----".length - signature_start); + } + } + + public class MessageFlag : Message.MessageFlag { + public const string id = "pgp"; + + public bool decrypted = false; + + public static MessageFlag? get_flag(Message.Stanza message) { + return (MessageFlag) message.get_flag(NS_URI, id); + } + + public override string get_ns() { return NS_URI; } + public override string get_id() { return id; } + } +} |