chatgui: invite link dialogs, zxing-cpp QR code, crypto transport, channel improvements; msg_transport: chat protocol support

tools/chatgui/src/invite_link.cpp

@@ -0,0 +1,100 @@
+#include "invite_link.h"
+#include "debug_ui.h"
+#include <QByteArray>
+
+static QByteArray encodeAddresses(const QList<NodeAddr>& addrs) {
+    QByteArray buf;
+    for (const auto& a : addrs) {
+        buf.append(static_cast<char>(a.family));
+        buf.append(a.address);
+        buf.append(static_cast<char>((a.port >> 8) & 0xFF));
+        buf.append(static_cast<char>(a.port & 0xFF));
+    }
+    return buf;
+}
+
+static QList<InviteAddr> decodeAddresses(const uint8_t* data, int len,
+                                          int count) {
+    QList<InviteAddr> list;
+    int off = 0;
+    for (int i = 0; i < count && off < len; i++) {
+        if (off + 1 > len) break;
+        InviteAddr a;
+        a.family = data[off++];
+        int alen = (a.family == 4) ? 4 : 16;
+        if (off + alen + 2 > len) break;
+        a.address = QByteArray(reinterpret_cast<const char*>(data + off), alen);
+        off += alen;
+        a.port = (static_cast<quint16>(data[off]) << 8) | data[off + 1];
+        off += 2;
+        list.append(a);
+    }
+    return list;
+}
+
+QString encodeInviteLink(const QString& channelId, const QByteArray& pubkey,
+                         const QList<NodeAddr>& addrs) {
+    QByteArray cid = channelId.toUtf8();
+    if (cid.size() > 65535) {
+        GUI_ERROR("encodeInviteLink: channelId too long (%d bytes)", cid.size());
+        return {};
+    }
+    if (pubkey.size() != 32) {
+        GUI_ERROR("encodeInviteLink: pubkey must be 32 bytes (got %d)", pubkey.size());
+        return {};
+    }
+
+    QByteArray addrsEnc = encodeAddresses(addrs);
+    int addrCount = addrs.size();
+    if (addrCount > 65535) addrCount = 65535;
+
+    QByteArray blob;
+    blob.reserve(1 + 2 + cid.size() + 32 + 2 + addrsEnc.size());
+    blob.append(static_cast<char>(INVITE_LINK_VERSION));
+    blob.append(static_cast<char>((cid.size() >> 8) & 0xFF));
+    blob.append(static_cast<char>(cid.size() & 0xFF));
+    blob.append(cid);
+    blob.append(pubkey);
+    blob.append(static_cast<char>((addrCount >> 8) & 0xFF));
+    blob.append(static_cast<char>(addrCount & 0xFF));
+    blob.append(addrsEnc);
+
+    return QString::fromLatin1("utun://") + QString::fromLatin1(blob.toBase64());
+}
+
+InviteData decodeInviteLink(const QString& link) {
+    InviteData d;
+    if (!link.startsWith(QLatin1String("utun://"))) {
+        GUI_ERROR("decodeInviteLink: invalid prefix");
+        return d;
+    }
+    QByteArray blob = QByteArray::fromBase64(
+        link.mid(7).toLatin1());
+    const auto* data = reinterpret_cast<const uint8_t*>(blob.constData());
+    int len = blob.size();
+
+    if (len < 5) {
+        GUI_ERROR("decodeInviteLink: blob too short (%d bytes)", len);
+        return d;
+    }
+    int off = 0;
+    uint8_t ver = data[off++];
+    if (ver != INVITE_LINK_VERSION) {
+        GUI_ERROR("decodeInviteLink: unsupported version %d", ver);
+        return d;
+    }
+    int cidLen = (static_cast<int>(data[off]) << 8) | data[off + 1];
+    off += 2;
+    if (off + cidLen + 32 + 2 > len) {
+        GUI_ERROR("decodeInviteLink: truncated blob");
+        return d;
+    }
+    d.channelId = QString::fromUtf8(reinterpret_cast<const char*>(data + off), cidLen);
+    off += cidLen;
+    d.pubkey = QByteArray(reinterpret_cast<const char*>(data + off), 32);
+    off += 32;
+    int addrCount = (static_cast<int>(data[off]) << 8) | data[off + 1];
+    off += 2;
+    d.addrs = decodeAddresses(data + off, len - off, addrCount);
+    return d;
+}