Real Hikvision/Dahua camera driver; gate Backend-push-IP on capability

Replace the camera stub with HttpCamera: Hikvision ISAPI and Dahua CGI
snapshots over client-side HTTP Digest (new drivers/http-digest.ts).
healthCheck() now pulls a real frame instead of returning ready/stub.
Snapshot carries bytes (driver fetches); storage/imageRef is the caller's
job, keeping the adapter free of storage deps.

Fix the cosmetic Backend-push-IP field: add pushesToBackend to DeviceDriver
(only Dingtian sets it), expose as pushCapable in the catalog, and gate the
wizard's backend-IP fetch + field on it so pull-only devices hide it.

Verified on hardware (Hikvision 10.0.10.121): healthCheck ready,
captureSnapshot returns a valid JPEG.

packages/devices/src/drivers/access-dingtian.ts

@@ -721,6 +721,7 @@ export const dingtianDriver: AccessDriver = {
   description:
     "Dingtian network relay+input board (UDP). Inputs are decoupled from relays — enables host-in-the-loop entry. Unauthenticated UDP: isolate the VLAN.",
   transports: ["udp"],
+  pushesToBackend: true, // HTTP-pushes input/button events to the backend (Input Link URL)
   configFields: [
     hostField,
     { ...portField(60001), required: false, help: "Dingtian string protocol UDP port — status read (default 60001)." },

packages/devices/src/drivers/camera.ts

@@ -1,57 +1,120 @@
 import type { CameraDevice, DeviceHealth, Snapshot, SnapshotContext } from "../interfaces.js";
-import type { CameraDriver, DeviceConfig } from "../registry.js";
+import type { CameraDriver, ConfigField, DeviceConfig } from "../registry.js";
 import { hostField, passwordField, portField, usernameField, stubLog } from "./common.js";
+import { digestGet } from "./http-digest.js";
 
-// Camera drivers — entry/exit snapshot-on-event. The image is stored and
-// referenced from the signed event as an independent fraud-control record.
-// Hikvision (ISAPI) and Dahua (CGI) differ only in the snapshot URL. STUBS only.
+// Camera drivers — entry/exit snapshot-on-event. The host pulls a still over
+// HTTP when an event fires; the bytes are stored and referenced from the signed
+// event as an independent fraud-control record (the camera PULLS, it never pushes
+// to us). Hikvision (ISAPI) and Dahua (CGI) differ only in the snapshot URL and
+// channel encoding. Both use HTTP Digest auth (see ./http-digest.ts).
+//
+// VERIFIED on hardware (2026-06-15): a Hikvision unit at 10.0.10.121 returns a
+// 2688×1520 JPEG from /ISAPI/Streaming/channels/101/picture with Digest auth.
+// See wiki/entities/lpr-camera.md.
+
+const DEFAULT_TIMEOUT_MS = 8000;
+
+class HttpCamera implements CameraDevice {
+  readonly #host: string;
+  readonly #port: number;
+  readonly #user: string;
+  readonly #password: string;
+  readonly #channel: number;
+  readonly #timeout: number;
+  // Source outbound from the device-facing NIC on a multi-homed host (the
+  // multi-subnet source-address trap — see wiki/concepts/wsl-dev-networking.md).
+  readonly #localAddress: string | undefined;
 
-class StubCamera implements CameraDevice {
   constructor(
     readonly driverId: string,
-    protected readonly config: DeviceConfig,
-    protected readonly snapshotPath: string,
-  ) {}
-  async connect(): Promise<void> {
-    stubLog(this.driverId, `connect ${this.config.host} (${this.snapshotPath})`);
-  }
-  async disconnect(): Promise<void> {
-    stubLog(this.driverId, "disconnect");
+    config: DeviceConfig,
+    /** Builds the snapshot path from the configured channel. */
+    private readonly snapshotPath: (channel: number) => string,
+  ) {
+    this.#host = String(config.host);
+    this.#port = Number(config.port ?? 80);
+    this.#user = String(config.username ?? "");
+    this.#password = String(config.password ?? "");
+    this.#channel = Number(config.channel ?? 1);
+    this.#timeout = Number(config.timeoutMs ?? DEFAULT_TIMEOUT_MS);
+    this.#localAddress = config.localAddress ? String(config.localAddress) : undefined;
   }
+
+  async connect(): Promise<void> {}
+  async disconnect(): Promise<void> {}
+
   async healthCheck(): Promise<DeviceHealth> {
-    return { status: "ready", detail: "stub" };
+    // The only honest liveness probe for a snapshot camera is to actually pull a
+    // frame: it exercises reachability + auth + the path/channel in one shot.
+    try {
+      const res = await this.#get();
+      if (res.status === 200) return { status: "ready", detail: `${res.body.length} bytes` };
+      if (res.status === 401) return { status: "degraded", detail: "auth rejected (check username/password)" };
+      return { status: "degraded", detail: `HTTP ${res.status}` };
+    } catch (err) {
+      return { status: "offline", detail: (err as Error).message };
+    }
   }
+
   async captureSnapshot(ctx: SnapshotContext): Promise<Snapshot> {
-    // Real driver: GET http(s)://host{snapshotPath}, store bytes, return ref.
-    stubLog(this.driverId, `captureSnapshot lane=${ctx.lane} ${ctx.direction}`);
+    const res = await this.#get();
+    if (res.status !== 200) {
+      throw new Error(
+        `${this.driverId} snapshot failed (lane=${ctx.lane} ${ctx.direction}): HTTP ${res.status}`,
+      );
+    }
+    stubLog(this.driverId, `captureSnapshot lane=${ctx.lane} ${ctx.direction} (${res.body.length} bytes)`);
     return {
-      imageRef: `stub://${this.driverId}/lane${ctx.lane}/${ctx.direction}/${Date.now()}`,
-      contentType: "image/jpeg",
+      bytes: res.body,
+      contentType: res.contentType || "image/jpeg",
       capturedAt: new Date().toISOString(),
     };
   }
+
+  #get() {
+    return digestGet({
+      host: this.#host,
+      port: this.#port,
+      path: this.snapshotPath(this.#channel),
+      user: this.#user,
+      password: this.#password,
+      timeoutMs: this.#timeout,
+      localAddress: this.#localAddress,
+    });
+  }
 }
 
-const cameraConfigFields = [hostField, portField(80), usernameField, passwordField, { key: "channel", label: "Channel", type: "number" as const, required: false, default: 1 }];
+const channelField: ConfigField = {
+  key: "channel",
+  label: "Channel",
+  type: "number",
+  required: false,
+  default: 1,
+};
+
+const cameraConfigFields = [hostField, portField(80), usernameField, passwordField, channelField];
 
 export const hikvisionDriver: CameraDriver = {
   id: "hikvision",
   category: "camera",
   label: "Hikvision camera",
-  description: "Hikvision snapshot via ISAPI.",
+  description: "Hikvision snapshot via ISAPI (HTTP Digest).",
   transports: ["tcp-ip"],
   configFields: cameraConfigFields,
-  // /ISAPI/Streaming/channels/<id>/picture
-  create: (c) => new StubCamera("hikvision", c, "/ISAPI/Streaming/channels/101/picture"),
+  // ISAPI channel id: <channel><stream>, e.g. ch1 main = 101, ch2 main = 201.
+  create: (c) =>
+    new HttpCamera("hikvision", c, (ch) => `/ISAPI/Streaming/channels/${ch}01/picture`),
 };
 
 export const dahuaDriver: CameraDriver = {
   id: "dahua",
   category: "camera",
   label: "Dahua camera",
-  description: "Dahua snapshot via CGI.",
+  description: "Dahua snapshot via CGI (HTTP Digest).",
   transports: ["tcp-ip"],
   configFields: cameraConfigFields,
-  // /cgi-bin/snapshot.cgi?channel=<n>
-  create: (c) => new StubCamera("dahua", c, "/cgi-bin/snapshot.cgi"),
+  // Dahua channels are 0-based on the CGI; the admin enters 1-based.
+  create: (c) =>
+    new HttpCamera("dahua", c, (ch) => `/cgi-bin/snapshot.cgi?channel=${Math.max(0, ch - 1)}`),
 };

packages/devices/src/drivers/http-digest.ts

@@ -0,0 +1,139 @@
+import { createHash, randomBytes } from "node:crypto";
+import { request as httpRequest } from "node:http";
+import type { IncomingMessage } from "node:http";
+
+// Client-side HTTP Digest auth (RFC 2617, MD5, qop=auth) for talking TO devices
+// that challenge with `WWW-Authenticate: Digest` — e.g. Hikvision ISAPI cameras.
+// (The server-side counterpart, which VERIFIES device→backend pushes, lives in
+// apps/server/src/digest-auth.ts.) Devices on the isolated VLAN can't present a
+// trusted TLS cert, so plain-HTTP Digest is the available auth: the password is
+// never on the wire, only a nonce-keyed hash. See wiki/concepts/network-isolation.md.
+
+const md5 = (s: string) => createHash("md5").update(s).digest("hex");
+
+/** Parse a `WWW-Authenticate: Digest …` header into its k=v fields. */
+function parseChallenge(header: string): Record<string, string> {
+  const out: Record<string, string> = {};
+  const re = /(\w+)=(?:"([^"]*)"|([^,]*))/g;
+  let m: RegExpExecArray | null;
+  while ((m = re.exec(header))) out[m[1]!] = (m[2] ?? m[3] ?? "").trim();
+  return out;
+}
+
+/** Build the `Authorization: Digest …` response value for a challenge. */
+function buildAuthHeader(
+  c: Record<string, string>,
+  user: string,
+  password: string,
+  method: string,
+  uri: string,
+): string {
+  const realm = c.realm ?? "";
+  const nonce = c.nonce ?? "";
+  const qop = c.qop?.split(",")[0]?.trim(); // server may offer "auth,auth-int"
+  const ha1 = md5(`${user}:${realm}:${password}`);
+  const ha2 = md5(`${method}:${uri}`);
+
+  const parts: string[] = [
+    `username="${user}"`,
+    `realm="${realm}"`,
+    `nonce="${nonce}"`,
+    `uri="${uri}"`,
+  ];
+
+  let response: string;
+  if (qop === "auth") {
+    const cnonce = randomBytes(8).toString("hex");
+    const nc = "00000001";
+    response = md5(`${ha1}:${nonce}:${nc}:${cnonce}:${qop}:${ha2}`);
+    parts.push(`qop=${qop}`, `nc=${nc}`, `cnonce="${cnonce}"`);
+  } else {
+    // Legacy RFC 2069 (no qop) — Hikvision uses qop=auth, but be tolerant.
+    response = md5(`${ha1}:${nonce}:${ha2}`);
+  }
+  parts.push(`response="${response}"`);
+  if (c.opaque) parts.push(`opaque="${c.opaque}"`);
+  return `Digest ${parts.join(", ")}`;
+}
+
+export interface DigestGetResult {
+  readonly status: number;
+  readonly contentType: string;
+  readonly body: Buffer;
+}
+
+export interface DigestGetOptions {
+  readonly host: string;
+  readonly port: number;
+  readonly path: string;
+  readonly user: string;
+  readonly password: string;
+  readonly timeoutMs: number;
+  /** Bind outbound to the device-facing NIC on a multi-homed host. */
+  readonly localAddress?: string;
+}
+
+function getOnce(
+  o: DigestGetOptions,
+  authHeader?: string,
+): Promise<{ res: IncomingMessage; body: Buffer }> {
+  return new Promise((resolve, reject) => {
+    const headers: Record<string, string> = {};
+    if (authHeader) headers["authorization"] = authHeader;
+    const req = httpRequest(
+      {
+        host: o.host,
+        port: o.port,
+        path: o.path,
+        method: "GET",
+        timeout: o.timeoutMs,
+        localAddress: o.localAddress,
+        headers,
+      },
+      (res) => {
+        const chunks: Buffer[] = [];
+        res.on("data", (c) => chunks.push(c as Buffer));
+        res.on("end", () => resolve({ res, body: Buffer.concat(chunks) }));
+      },
+    );
+    req.on("error", reject);
+    req.on("timeout", () => req.destroy(new Error("digest GET timeout")));
+    req.end();
+  });
+}
+
+/**
+ * GET a resource with HTTP Digest auth. Does the standard two-shot handshake:
+ * the first request (no Authorization) draws a 401 + challenge, the second
+ * carries the computed response. If the server doesn't challenge (200 straight
+ * away, or no auth required), the first response is returned as-is.
+ */
+export async function digestGet(o: DigestGetOptions): Promise<DigestGetResult> {
+  const first = await getOnce(o);
+  if (first.res.statusCode !== 401) {
+    return {
+      status: first.res.statusCode ?? 0,
+      contentType: String(first.res.headers["content-type"] ?? ""),
+      body: first.body,
+    };
+  }
+
+  const challengeHeader = String(first.res.headers["www-authenticate"] ?? "");
+  if (!/^digest/i.test(challengeHeader)) {
+    // 401 but not Digest (e.g. Basic-only) — surface it; caller decides.
+    return {
+      status: 401,
+      contentType: String(first.res.headers["content-type"] ?? ""),
+      body: first.body,
+    };
+  }
+
+  const challenge = parseChallenge(challengeHeader);
+  const auth = buildAuthHeader(challenge, o.user, o.password, "GET", o.path);
+  const second = await getOnce(o, auth);
+  return {
+    status: second.res.statusCode ?? 0,
+    contentType: String(second.res.headers["content-type"] ?? ""),
+    body: second.body,
+  };
+}

packages/devices/src/interfaces.ts

@@ -179,10 +179,15 @@ export interface SnapshotContext {
 }
 
 export interface Snapshot {
-  /** Storage reference for the captured image (file path / blob id). */
-  readonly imageRef: string;
+  /** The captured image bytes. The DRIVER fetches them over the network; the
+   *  CALLER (entry/exit flow) owns storage and minting a durable reference —
+   *  keeping the device adapter free of any filesystem/blob-store dependency. */
+  readonly bytes: Buffer;
   readonly contentType: string;
   readonly capturedAt: string; // ISO-8601
+  /** Storage reference (file path / blob id), set once the caller has stored
+   *  the bytes. Absent on the value the driver returns. */
+  readonly imageRef?: string;
 }
 
 // --- Printers (ticket dispenser / booth printer) -------------------------

packages/devices/src/registry.ts

@@ -42,6 +42,13 @@ export interface DeviceDriver<T extends Device = Device> {
   /** Transports/notes surfaced in the UI, e.g. ["tcp-ip"], ["wiegand"]. */
   readonly transports: readonly string[];
   readonly configFields: readonly ConfigField[];
+  /**
+   * True if the device calls BACK to our backend (HTTP push) and therefore needs
+   * a backend IP configured at assign time. Pull-only devices (cameras poll a
+   * snapshot, the relay is commanded) leave this false so the setup wizard hides
+   * the "Backend push IP" field. See wiki/concepts/device-input-flow.md.
+   */
+  readonly pushesToBackend?: boolean;
   /** Build a live adapter instance from validated config. */
   create(config: DeviceConfig): T;
 }
@@ -130,6 +137,11 @@ class DeviceRegistry {
     }
     return byCategory;
   }
+
+  /** Driver ids that push to the backend (need a backend IP at assign time). */
+  pushCapable(): string[] {
+    return [...this.#drivers.values()].filter((d) => d.pushesToBackend).map((d) => d.id);
+  }
 }
 
 export interface CatalogEntry {