Add Key rotation policy.

src/endpoints/keyEndpoint.ts

@@ -11,9 +11,11 @@ import { IAttestationReport } from "../attestation/ISnpAttestationReport";
 import { IKeyItem } from "./IKeyItem";
 import { KeyGeneration } from "./KeyGeneration";
 import { validateAttestation } from "../attestation/AttestationValidation";
-import { hpkeKeyIdMap, hpkeKeysMap } from "../repositories/Maps";
+import { hpkeKeyIdMap, hpkeKeysMap, keyRotationPolicyMap } from "../repositories/Maps";
 import { ServiceRequest } from "../utils/ServiceRequest";
 import { LogContext, Logger } from "../utils/Logger";
+import { TrustedTime } from "../utils/TrustedTime";
+import { KeyRotationPolicy } from "../policies/KeyRotationPolicy";
 
 // Enable the endpoint
 enableEndpoint();
@@ -175,6 +177,40 @@ export const key = (
       logContext
     );
   }
+
+  const keyRotation = KeyRotationPolicy.loadKeyRotationPolicyFromMap(
+    keyRotationPolicyMap,
+    logContext
+  ).keyRotationPolicy;
+  const gracePeriodSeconds = keyRotation.gracePeriodSeconds;
+  const rotationIntervalSeconds = keyRotation.rotationIntervalSeconds;
+  // Get the current time using TrustedTime
+  const currentTime = TrustedTime.getCurrentTime();
+  const currentDate = new Date(currentTime);
+
+  // Get the creation date of the key
+  const creationDate = new Date(keyItem.timestamp!);
+
+  // Calculate the expiry date of the key by adding the rotation interval to the creation date
+  const expiryDateMillis =
+    creationDate.getTime() + rotationIntervalSeconds * 1000;
+  const expiryDate = new Date(expiryDateMillis);
+  // Calculate the grace period start date by subtracting the grace period from the expiry date
+  const gracePeriodMillis = gracePeriodSeconds * 1000;
+  const gracePeriodStartDate = new Date(
+    expiryDate.getTime() - gracePeriodMillis
+  );
+
+  if (currentDate > expiryDate) {
+    return ServiceResult.Failed<string>(
+      { errorMessage: `${name}: Key has expired and is no longer valid` },
+      400,
+      logContext
+    );
+  } else if (currentDate > gracePeriodStartDate) {
+    Logger.warn(`${name}: Key is deprecated and will expire soon`);
+  }
+
   const receipt = hpkeKeysMap.receipt(kid);
 
   if (validateAttestationResult.statusCode === 202) {

src/policies/IKeyRotationPolicy.ts

@@ -0,0 +1,4 @@
+export interface IKeyRotationPolicy {
+    rotationIntervalSeconds: number;
+    gracePeriodSeconds: number;
+}

src/policies/KeyRotationPolicy.ts

@@ -0,0 +1,101 @@
+import * as ccfapp from "@microsoft/ccf-app";
+import { ccf } from "@microsoft/ccf-app/global";
+import { IKeyRotationPolicy } from "./IKeyRotationPolicy";
+import { Logger, LogContext } from "../utils/Logger";
+import { KmsError } from "../utils/KmsError";
+
+/**
+ * Class representing a Key Rotation Policy.
+ */
+export class KeyRotationPolicy {
+  /**
+   * Constructs a new KeyRotationPolicy instance.
+   * @param keyRotationPolicy - The key rotation policy settings.
+   */
+  constructor(public keyRotationPolicy: IKeyRotationPolicy) {}
+
+  /**
+   * The log context for the KeyRotationPolicy class.
+   * @private
+   */
+  private static readonly logContext = new LogContext().appendScope(
+    "KeyRotationPolicy"
+  );
+
+  /**
+   * Returns the default key rotation policy.
+   * @returns The default key rotation policy.
+   */
+  public static defaultKeyRotationPolicy(): IKeyRotationPolicy {
+    return {
+      rotationIntervalSeconds: 300,
+      gracePeriodSeconds: 60,
+    };
+  }
+
+  /**
+   * Logs the key rotation policy settings.
+   * @param keyRotationPolicy - The key rotation policy to log.
+   */
+  public static logKeyRotationPolicy(
+    keyRotationPolicy: IKeyRotationPolicy
+  ): void {
+    Logger.debug(
+      `Rotation Interval Seconds: ${keyRotationPolicy.rotationIntervalSeconds}`,
+      KeyRotationPolicy.logContext
+    );
+    Logger.debug(
+      `Grace Period Seconds: ${keyRotationPolicy.gracePeriodSeconds}`,
+      KeyRotationPolicy.logContext
+    );
+  }
+
+  /**
+   * Loads the key rotation from the key rotation policy map.
+   * If a key rotation policy is found, it is parsed and returned as an instance of `KeyRotationPolicy`.
+   * If no key rotation policy is found, default key rotation policy are used.
+   * @param keyRotationPolicyMap - The map containing the key rotation policy.
+   * @param logContextIn - The log context to use.
+   * @returns A new KeyRotationPolicy instance.
+   * @throws {KmsError} If the key rotation policy cannot be parsed.
+   */
+  public static loadKeyRotationPolicyFromMap(
+    keyRotationPolicyMap: ccfapp.KvMap,
+    logContextIn: LogContext
+  ): KeyRotationPolicy {
+    const logContext = (logContextIn?.clone() || new LogContext()).appendScope(
+      "loadKeyRotationPolicyFromMap"
+    );
+
+    // Load the key rotation from the map
+    const key = "key_rotation_policy"; // Ensure the key matches the stored key in governance
+    const keyBuf = ccf.strToBuf(key);
+
+    const keyRotationPolicy = keyRotationPolicyMap.get(keyBuf);
+    const keyRotationPolicyStr = keyRotationPolicy
+      ? ccf.bufToStr(keyRotationPolicy)
+      : undefined;
+    Logger.debug(
+      `Loading key rotation policy: ${keyRotationPolicyStr}`,
+      logContext
+    );
+
+    let keyRotation: IKeyRotationPolicy;
+    if (!keyRotationPolicyStr) {
+      Logger.warn(
+        `No key rotation policy found, using default key rotation policy`,
+        logContext
+      );
+      keyRotation = KeyRotationPolicy.defaultKeyRotationPolicy();
+    } else {
+      try {
+        keyRotation = JSON.parse(keyRotationPolicyStr) as IKeyRotationPolicy;
+      } catch {
+        const error = `Failed to parse key rotation policy: ${keyRotationPolicyStr}`;
+        Logger.error(error, logContext);
+        throw new KmsError(error, logContext);
+      }
+    }
+    return new KeyRotationPolicy(keyRotation);
+  }
+}

src/repositories/Maps.ts

@@ -13,4 +13,6 @@ export const keyReleaseMapName = "public:ccf.gov.policies.key_release";
 export const keyReleasePolicyMap = ccf.kv[keyReleaseMapName];
 export const settingsMapName = "public:ccf.gov.policies.settings";
 export const settingsPolicyMap = ccf.kv[settingsMapName];
+export const keyRotationMapName = "public:ccf.gov.policies.key_rotation";
+export const keyRotationPolicyMap = ccf.kv[keyRotationMapName];
 //#endregion

src/utils/TrustedTime.ts

@@ -0,0 +1,12 @@
+export class TrustedTime {
+  private static lastTimestamp: number = 0;
+
+  public static getCurrentTime(): number {
+    const currentTime = Date.now();
+    if (currentTime <= this.lastTimestamp) {
+      throw new Error("System time moved backwards.");
+    }
+    this.lastTimestamp = currentTime;
+    return currentTime;
+  }
+}