From 2a9f06650014b1568ce618d00b45b80736982b92 Mon Sep 17 00:00:00 2001
From: Enzo Cioppettini <enzo.cioppettini@globant.com>
Date: Mon, 6 Nov 2023 23:15:09 -0300
Subject: [PATCH] add delegation check in batcher's address validator

---
 .../batcher/address-validator/package.json    |  3 +-
 .../batcher/address-validator/src/index.ts    | 34 +++++++++++++++++++
 packages/batcher/utils/src/config.ts          |  8 +++++
 3 files changed, 44 insertions(+), 1 deletion(-)

diff --git a/packages/batcher/address-validator/package.json b/packages/batcher/address-validator/package.json
index 032b5e7da..e7b754330 100644
--- a/packages/batcher/address-validator/package.json
+++ b/packages/batcher/address-validator/package.json
@@ -12,7 +12,8 @@
   "dependencies": {
     "pg": "^8.7.3",
     "web3": "1.10.0",
-    "assert-never": "^1.2.1"
+    "assert-never": "^1.2.1",
+    "@dcspark/carp-client": "../../../tmp-carp-client"
   },
   "devDependencies": {
     "@types/pg": "^8.6.5"
diff --git a/packages/batcher/address-validator/src/index.ts b/packages/batcher/address-validator/src/index.ts
index ffafa3c6a..e329650e0 100644
--- a/packages/batcher/address-validator/src/index.ts
+++ b/packages/batcher/address-validator/src/index.ts
@@ -17,6 +17,8 @@ import { CryptoManager } from '@paima/crypto';
 import { createMessageForBatcher } from '@paima/concise';
 import { initWeb3, AddressType, getReadNamespaces } from '@paima/utils';
 import assertNever from 'assert-never';
+import { query, getErrorResponse } from '@dcspark/carp-client/client/src/index';
+import { Routes } from '@dcspark/carp-client/shared/routes';
 
 class PaimaAddressValidator {
   private web3: Web3 | undefined;
@@ -59,6 +61,13 @@ class PaimaAddressValidator {
       return GenericRejectionCode.ADDRESS_NOT_ALLOWED;
     }
 
+    // If a list of allowed cardano pools is provided, check that this user is delegating to that address
+    const isDelegatingToAllowedPools = await this.isDelegatingToAllowedPools(input.userAddress);
+    if (!isDelegatingToAllowedPools) {
+      console.log('[address-validator] Address not allowed!');
+      return GenericRejectionCode.ADDRESS_NOT_ALLOWED;
+    }
+
     // All tests passed:
     return 0;
   };
@@ -208,6 +217,31 @@ class PaimaAddressValidator {
   ): boolean {
     return inputsMinute < ENV.MAX_USER_INPUTS_PER_MINUTE && inputsDay < ENV.MAX_USER_INPUTS_PER_DAY;
   }
+
+  private isDelegatingToAllowedPools = async (userAddress: string): Promise<boolean> => {
+    const pools = ENV.BATCHER_CARDANO_ENABLED_POOLS;
+
+    if (!pools) {
+      return true;
+    }
+
+    if (!ENV.CARP_URL) {
+      throw new Error(`[address-validator] missing CARP_URL setting`);
+    }
+
+    const latest = await query(ENV.CARP_URL, Routes.blockLatest, {
+      offset: 0,
+    });
+
+    const delegatingTo = await query(ENV.CARP_URL, Routes.delegationForAddress, {
+      address: userAddress,
+      until: {
+        absoluteSlot: latest.block.slot,
+      },
+    });
+
+    return !!pools.find(pool => delegatingTo.pool === pool);
+  };
 }
 
 export default PaimaAddressValidator;
diff --git a/packages/batcher/utils/src/config.ts b/packages/batcher/utils/src/config.ts
index 6d6bb52a4..761989fbb 100644
--- a/packages/batcher/utils/src/config.ts
+++ b/packages/batcher/utils/src/config.ts
@@ -84,6 +84,14 @@ export class ENV {
     return parseInt(process.env.MAX_USER_INPUTS_PER_DAY || '0', 10);
   }
 
+  static get CARP_URL(): string | undefined {
+    return process.env.BATCHER_CARP_URL;
+  }
+
+  static get BATCHER_CARDANO_ENABLED_POOLS(): string[] | undefined {
+    return process.env.BATCHER_CARDANO_ENABLED_POOLS?.split(',');
+  }
+
   // NOTE: this variable is not currently used, with DEFAULT_VALIDATION_ACTIVE determining the type.
   static get GAME_INPUT_VALIDATION_TYPE_NAME(): string {
     return process.env.GAME_INPUT_VALIDATION_TYPE_NAME || '';