feat: verify path for multiple hops

IndexCoop · May 27, 2021 · 06ca9b6 · 06ca9b6
1 parent 7905d73
commit 06ca9b6
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Showing 2 changed files with 41 additions and 43 deletions.
diff --git a/contracts/protocol/integration/exchange/ZeroExApiAdapter.sol b/contracts/protocol/integration/exchange/ZeroExApiAdapter.sol
@@ -52,22 +52,21 @@ contract ZeroExApiAdapter {
         bytes data;
     }
 
-
     /* ============ State Variables ============ */
 
     // ETH pseudo-token address used by 0x API.
     address private constant ETH_ADDRESS = 0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE;
 
     // Minimum byte size of a single hop Uniswap V3 encoded path
     uint256 private constant UNISWAP_V3_SINGLE_HOP_PATH_SIZE = 20 + 3 + 20;
+    uint256 private constant UNISWAP_V3_SINGLE_HOP_OFFSET_SIZE = 20 + 3;
 
     // Address of the deployed ZeroEx contract.
     address public immutable zeroExAddress;
 
     // Returns the address to approve source tokens to for trading. This is the TokenTaker address
     address public immutable getSpender;
 
-
     /* ============ constructor ============ */
 
     constructor(address _zeroExAddress) public {
@@ -164,7 +163,17 @@ contract ZeroExApiAdapter {
                     abi.decode(_data[4:], (bytes, uint256, uint256, address));
                 supportsRecipient = true;
 
-                (inputToken, outputToken) = _decodePoolInfoFromPath(encodedPath);
+                uint256 numHops = (encodedPath.length - 20)/UNISWAP_V3_SINGLE_HOP_OFFSET_SIZE;
+                require(numHops > 0, "At least 1 hop");
+
+                if (numHops == 1) {
+                    (inputToken, outputToken) = _decodePoolInfoFromPathWithOffset(encodedPath, 0);
+
+                } else {
+                    uint256 lastPoolOffset = (numHops - 1) * UNISWAP_V3_SINGLE_HOP_OFFSET_SIZE;
+                    (inputToken,) = _decodePoolInfoFromPathWithOffset(encodedPath, 0);
+                    (, outputToken) = _decodePoolInfoFromPathWithOffset(encodedPath, lastPoolOffset);
+                }
             }
             else {
                 revert("Unsupported 0xAPI function selector");
@@ -186,7 +195,7 @@ contract ZeroExApiAdapter {
     }
 
     // Return the first input token, output token, and fee of an encoded uniswap path.
-    function _decodePoolInfoFromPath(bytes memory encodedPath)
+    function _decodePoolInfoFromPathWithOffset(bytes memory encodedPath, uint256 offset)
         private
         pure
         returns (
@@ -197,6 +206,7 @@ contract ZeroExApiAdapter {
         require(encodedPath.length >= UNISWAP_V3_SINGLE_HOP_PATH_SIZE, "Uniswap token path too shor too shortt");
         assembly {
             let p := add(encodedPath, 32)
+            p := add(p, offset)
             inputToken := shr(96, mload(p))
             p := add(p, 20)
             // account for fee

diff --git a/test/protocol/integration/exchange/zeroExApiAdapter.spec.ts b/test/protocol/integration/exchange/zeroExApiAdapter.spec.ts
@@ -6,6 +6,7 @@ import { ZeroExApiAdapter, ZeroExMock } from "@utils/contracts";
 import DeployHelper from "@utils/deploys";
 import { addSnapshotBeforeRestoreAfterEach, getAccounts, getWaffleExpect } from "@utils/test/index";
 import { hexUtils } from "@0x/utils";
+import { take } from "lodash";
 
 const expect = getWaffleExpect();
 
@@ -14,6 +15,7 @@ describe("ZeroExApiAdapter", () => {
   const sourceToken = "0x6cf5f1d59fddae3a688210953a512b6aee6ea643";
   const destToken = "0x5e5d0bea9d4a15db2d0837aff0435faba166190d";
   const otherToken = "0xae9902bb655de1a67f334d8661b3ae6a96723d5b";
+  const extraHopToken = "0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48";
   const destination = "0x89b3515cad4f23c1deacea79fc12445cc21bd0e1";
   const otherDestination = "0xdeb100c55cccfd6e39753f78c8b0c3bcbef86157";
   const sourceQuantity = ONE;
@@ -656,45 +658,31 @@ describe("ZeroExApiAdapter", () => {
     }
 
     describe("sellTokenForTokenToUniswapV3", () => {
-      it("validates data", async () => {
-        const data = zeroExMock.interface.encodeFunctionData("sellTokenForTokenToUniswapV3", [
-          encodePath([sourceToken, destToken]),
-          sourceQuantity,
-          minDestinationQuantity,
-          destination,
-        ]);
-        console.log(data);
-        const [target, value, _data] = await zeroExApiAdapter.getTradeCalldata(
-          sourceToken,
-          destToken,
-          destination,
-          sourceQuantity,
-          minDestinationQuantity,
-          data,
-        );
-        expect(target).to.eq(zeroExMock.address);
-        expect(value).to.deep.eq(ZERO);
-        expect(_data).to.deep.eq(data);
-      });
-      it("multiple hops: validates data", async () => {
-        const data = zeroExMock.interface.encodeFunctionData("sellTokenForTokenToUniswapV3", [
-          encodePath([sourceToken, otherToken, destToken]),
-          sourceQuantity,
-          minDestinationQuantity,
-          destination,
-        ]);
-        const [target, value, _data] = await zeroExApiAdapter.getTradeCalldata(
-          sourceToken,
-          destToken,
-          destination,
-          sourceQuantity,
-          minDestinationQuantity,
-          data,
-        );
-        expect(target).to.eq(zeroExMock.address);
-        expect(value).to.deep.eq(ZERO);
-        expect(_data).to.deep.eq(data);
-      });
+      const additionalHops = [otherToken, extraHopToken];
+      for (let i = 0; i <= additionalHops.length; i++) {
+        const hops = take(additionalHops, i);
+        it(`validates data for ${i + 1} hops`, async () => {
+          const path = [sourceToken, ...hops, destToken];
+
+          const data = zeroExMock.interface.encodeFunctionData("sellTokenForTokenToUniswapV3", [
+            encodePath(path),
+            sourceQuantity,
+            minDestinationQuantity,
+            destination,
+          ]);
+          const [target, value, _data] = await zeroExApiAdapter.getTradeCalldata(
+            sourceToken,
+            destToken,
+            destination,
+            sourceQuantity,
+            minDestinationQuantity,
+            data,
+          );
+          expect(target).to.eq(zeroExMock.address);
+          expect(value).to.deep.eq(ZERO);
+          expect(_data).to.deep.eq(data);
+        });
+      }
     });
   });
 });