[feat] use device keys for server login

2026-11-03 20:47:43 +08:00 · 2026-11-02 01:15:11 +08:00
parent bb48551d59
commit 49717f0f68
17 changed files with 225 additions and 41 deletions
@@ -0,0 +1,71 @@
+#include "runtime/device_login.h"
+
+#include <algorithm>
+#include <cstring>
+
+#include "runtime/trusted_devices.h"
+
+namespace crossdesk {
+int DeviceLogin::Exchange(SignalExchangeStage stage, const nlohmann::json& message,
+    const TrustedDevices* identity, char* response, size_t capacity) {
+  auto output = [&](const nlohmann::json& reply) {
+    const auto text = reply.dump();
+    if (text.empty() || text.size() > capacity) return -1;
+    std::memcpy(response, text.data(), text.size());
+    return static_cast<int>(text.size());
+  };
+  if (stage == SignalExchangeStage::PrepareLogin) {
+    phase_ = Phase::Idle;
+    used_password_ = false;
+    password_.clear();
+    request_ = message;
+    const auto login = message.at("user_id").get<std::string>();
+    if (login.rfind("C-", 0) == 0) return 0;
+    if (!identity) return -1;  // Never fall back when local key storage fails.
+    const auto at = login.find('@');
+    request_["user_id"] = login.substr(0, at);
+    if (at != std::string::npos) password_ = login.substr(at + 1);
+    request_["device_key"] = {{"version", 1}, {"public_key", identity->PublicKey()}};
+    request_.erase("reconnect_token");
+    request_.erase("reconnect_version");
+    phase_ = Phase::AwaitingChallenge;
+    return output(request_);
+  }
+  if (!Pending()) return 0;
+  const auto type = message.value("type", "");
+  if (type == "login_challenge") {
+    if (!identity || phase_ != Phase::AwaitingChallenge || message.at("device_key_version") != 1 ||
+        message.at("user_id") != request_.at("user_id")) return -1;
+    const auto nonce = message.at("nonce").get<std::string>();
+    if (nonce.size() != 64 || !std::all_of(nonce.begin(), nonce.end(),
+        [](char c) { return (c >= '0' && c <= '9') || (c >= 'a' && c <= 'f'); }))
+      return -1;
+    const auto id = request_.at("user_id").get<std::string>();
+    auto reply = request_;
+    used_password_ = message.at("password_required").get<bool>();
+    if (used_password_) {
+      if (id.empty() || password_.empty()) return -1;
+      reply["user_id"] = id + "@" + password_;
+    }
+    const auto transcript = nlohmann::json::array(
+        {"crossdesk.device-login.v1", id, identity->PublicKey(), nonce}).dump();
+    reply["device_key"]["nonce"] = nonce;
+    reply["device_key"]["signature"] = identity->Sign(transcript);
+    phase_ = Phase::AwaitingResult;
+    password_.clear();
+    return output(reply);
+  }
+  if (type == "login") {
+    if (message.at("status") == "success") {
+      if (phase_ != Phase::AwaitingResult || message.value("device_key_version", 0) != 1) return -1;
+      const auto assigned = message.at("user_id").get<std::string>();
+      const auto expected = request_.at("user_id").get<std::string>();
+      if (assigned.empty() || (!expected.empty() && assigned != expected)) return -1;
+    }
+    password_.clear();
+    request_.clear();
+    phase_ = Phase::Idle;
+  }
+  return 0;
+}
+}  // namespace crossdesk