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fix: stop swallowing facilitator verification errors #18

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fix: stop swallowing facilitator verification errors #18

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47 changes: 42 additions & 5 deletions typescript/packages/mechanisms/evm/src/exact/facilitator/eip3009.ts
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Original file line number Diff line number Diff line change
Expand Up @@ -9,6 +9,10 @@ import { authorizationTypes, eip3009ABI } from "../../constants";
import { FacilitatorEvmSigner } from "../../signer";
import { ExactEIP3009Payload } from "../../types";

function toErrorMessage(error: unknown): string {
return error instanceof Error ? error.message : String(error);
}

export interface EIP3009FacilitatorConfig {
/**
* If enabled, the facilitator will deploy ERC-4337 smart wallets
Expand Down Expand Up @@ -101,7 +105,9 @@ export async function verifyEIP3009(
payer,
};
}
} catch {
} catch (error) {
console.warn("EIP-3009 signature verification threw an error:", toErrorMessage(error));

// Signature verification failed - could be an undeployed smart wallet
// Check if smart wallet is deployed
const signature = eip3009Payload.signature!;
Expand All @@ -110,11 +116,35 @@ export async function verifyEIP3009(

if (isSmartWallet) {
const payerAddress = eip3009Payload.authorization.from;
const bytecode = await signer.getCode({ address: payerAddress });
let bytecode: Hex;
try {
bytecode = await signer.getCode({ address: payerAddress });
} catch (getCodeError) {
const message = toErrorMessage(getCodeError);
console.warn("Failed to inspect smart wallet bytecode during verification:", message);
return {
isValid: false,
invalidReason: "invalid_exact_evm_payload_signature_verification_error",
invalidMessage: message,
payer,
};
}

if (!bytecode || bytecode === "0x") {
// Wallet is not deployed. Check if it's EIP-6492 with deployment info.
const erc6492Data = parseErc6492Signature(signature);
let erc6492Data: ReturnType<typeof parseErc6492Signature>;
try {
erc6492Data = parseErc6492Signature(signature);
} catch (parseError) {
const message = toErrorMessage(parseError);
console.warn("Failed to parse EIP-6492 signature payload:", message);
return {
isValid: false,
invalidReason: "invalid_exact_evm_payload_signature",
invalidMessage: message,
payer,
};
}
const hasDeploymentInfo =
erc6492Data.address &&
erc6492Data.data &&
Expand Down Expand Up @@ -192,8 +222,15 @@ export async function verifyEIP3009(
payer,
};
}
} catch {
// If we can't check balance, continue with other validations
} catch (error) {
const message = toErrorMessage(error);
console.warn("EIP-3009 balance check failed during verification:", message);
return {
isValid: false,
invalidReason: "invalid_exact_evm_payload_balance_check_failed",
invalidMessage: message,
payer,
};
}

// Verify amount is sufficient
Expand Down
33 changes: 27 additions & 6 deletions typescript/packages/mechanisms/evm/src/exact/facilitator/permit2.ts
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Original file line number Diff line number Diff line change
Expand Up @@ -15,6 +15,10 @@ import {
import { FacilitatorEvmSigner } from "../../signer";
import { ExactPermit2Payload } from "../../types";

function toErrorMessage(error: unknown): string {
return error instanceof Error ? error.message : String(error);
}

// ERC20 allowance ABI for checking Permit2 approval
const erc20AllowanceABI = [
{
Expand Down Expand Up @@ -167,10 +171,13 @@ export async function verifyPermit2(
payer,
};
}
} catch {
} catch (error) {
const message = toErrorMessage(error);
console.warn("Permit2 signature verification threw an error:", message);
return {
isValid: false,
invalidReason: "invalid_permit2_signature",
invalidReason: "invalid_permit2_signature_verification_error",
invalidMessage: message,
payer,
};
}
Expand All @@ -191,8 +198,15 @@ export async function verifyPermit2(
payer,
};
}
} catch {
// If we can't check allowance, continue - settlement will fail if insufficient
} catch (error) {
const message = toErrorMessage(error);
console.warn("Permit2 allowance check failed during verification:", message);
return {
isValid: false,
invalidReason: "permit2_allowance_check_failed",
invalidMessage: message,
payer,
};
}

// Check balance
Expand All @@ -212,8 +226,15 @@ export async function verifyPermit2(
payer,
};
}
} catch {
// If we can't check balance, continue with other validations
} catch (error) {
const message = toErrorMessage(error);
console.warn("Permit2 balance check failed during verification:", message);
return {
isValid: false,
invalidReason: "permit2_balance_check_failed",
invalidMessage: message,
payer,
};
}

return {
Expand Down
173 changes: 173 additions & 0 deletions typescript/packages/mechanisms/evm/test/unit/exact/facilitator.test.ts
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Original file line number Diff line number Diff line change
Expand Up @@ -460,6 +460,148 @@ describe("ExactEvmScheme (Facilitator)", () => {
expect(result.invalidReason).toBe("invalid_permit2_recipient_mismatch");
expect(result.payer).toBe(mockClientSigner.address);
});

it("should fail Permit2 verification when allowance check throws", async () => {
const requirements: PaymentRequirements = {
scheme: "exact",
network: "eip155:84532",
amount: "1000000",
asset: "0x036CbD53842c5426634e7929541eC2318f3dCF7e",
payTo: "0x742d35Cc6634C0532925a3b844Bc9e7595f0bEb0",
maxTimeoutSeconds: 300,
extra: { name: "USDC", version: "2", assetTransferMethod: "permit2" },
};

mockFacilitatorSigner.readContract = vi
.fn()
.mockRejectedValue(new Error("allowance rpc timeout"));

const permit2Payload: PaymentPayload = {
x402Version: 2,
payload: {
signature: "0xmocksignature",
permit2Authorization: {
from: mockClientSigner.address,
permitted: {
token: requirements.asset,
amount: requirements.amount,
},
spender: x402ExactPermit2ProxyAddress,
nonce: "12345",
deadline: "999999999999",
witness: {
to: requirements.payTo,
validAfter: "0",
extra: "0x",
},
},
},
accepted: requirements,
resource: { url: "", description: "", mimeType: "" },
};

const result = await facilitator.verify(permit2Payload, requirements);

expect(result.isValid).toBe(false);
expect(result.invalidReason).toBe("permit2_allowance_check_failed");
expect(result.invalidMessage).toContain("allowance rpc timeout");
expect(result.payer).toBe(mockClientSigner.address);
});

it("should fail Permit2 verification when balance check throws", async () => {
const requirements: PaymentRequirements = {
scheme: "exact",
network: "eip155:84532",
amount: "1000000",
asset: "0x036CbD53842c5426634e7929541eC2318f3dCF7e",
payTo: "0x742d35Cc6634C0532925a3b844Bc9e7595f0bEb0",
maxTimeoutSeconds: 300,
extra: { name: "USDC", version: "2", assetTransferMethod: "permit2" },
};

mockFacilitatorSigner.readContract = vi
.fn()
.mockResolvedValueOnce(BigInt("10000000000"))
.mockRejectedValueOnce(new Error("balance rpc timeout"));

const permit2Payload: PaymentPayload = {
x402Version: 2,
payload: {
signature: "0xmocksignature",
permit2Authorization: {
from: mockClientSigner.address,
permitted: {
token: requirements.asset,
amount: requirements.amount,
},
spender: x402ExactPermit2ProxyAddress,
nonce: "12345",
deadline: "999999999999",
witness: {
to: requirements.payTo,
validAfter: "0",
extra: "0x",
},
},
},
accepted: requirements,
resource: { url: "", description: "", mimeType: "" },
};

const result = await facilitator.verify(permit2Payload, requirements);

expect(result.isValid).toBe(false);
expect(result.invalidReason).toBe("permit2_balance_check_failed");
expect(result.invalidMessage).toContain("balance rpc timeout");
expect(result.payer).toBe(mockClientSigner.address);
});

it("should return a specific code when Permit2 signature verification throws", async () => {
const requirements: PaymentRequirements = {
scheme: "exact",
network: "eip155:84532",
amount: "1000000",
asset: "0x036CbD53842c5426634e7929541eC2318f3dCF7e",
payTo: "0x742d35Cc6634C0532925a3b844Bc9e7595f0bEb0",
maxTimeoutSeconds: 300,
extra: { name: "USDC", version: "2", assetTransferMethod: "permit2" },
};

mockFacilitatorSigner.verifyTypedData = vi
.fn()
.mockRejectedValue(new Error("typed-data verifier crashed"));

const permit2Payload: PaymentPayload = {
x402Version: 2,
payload: {
signature: "0xmocksignature",
permit2Authorization: {
from: mockClientSigner.address,
permitted: {
token: requirements.asset,
amount: requirements.amount,
},
spender: x402ExactPermit2ProxyAddress,
nonce: "12345",
deadline: "999999999999",
witness: {
to: requirements.payTo,
validAfter: "0",
extra: "0x",
},
},
},
accepted: requirements,
resource: { url: "", description: "", mimeType: "" },
};

const result = await facilitator.verify(permit2Payload, requirements);

expect(result.isValid).toBe(false);
expect(result.invalidReason).toBe("invalid_permit2_signature_verification_error");
expect(result.invalidMessage).toContain("typed-data verifier crashed");
expect(result.payer).toBe(mockClientSigner.address);
});
});

describe("Permit2 settlement", () => {
Expand Down Expand Up @@ -556,6 +698,37 @@ describe("ExactEvmScheme (Facilitator)", () => {
});

describe("Error cases", () => {
it("should fail EIP-3009 verification when balance check throws", async () => {
const requirements: PaymentRequirements = {
scheme: "exact",
network: "eip155:84532",
amount: "1000000",
asset: "0x036CbD53842c5426634e7929541eC2318f3dCF7e",
payTo: "0x742d35Cc6634C0532925a3b844Bc9e7595f0bEb0",
maxTimeoutSeconds: 300,
extra: { name: "USDC", version: "2" },
};

mockFacilitatorSigner.readContract = vi
.fn()
.mockRejectedValue(new Error("balance rpc unavailable"));

const paymentPayload = await client.createPaymentPayload(2, requirements);

const fullPayload: PaymentPayload = {
...paymentPayload,
accepted: requirements,
resource: { url: "", description: "", mimeType: "" },
};

const result = await facilitator.verify(fullPayload, requirements);

expect(result.isValid).toBe(false);
expect(result.invalidReason).toBe("invalid_exact_evm_payload_balance_check_failed");
expect(result.invalidMessage).toContain("balance rpc unavailable");
expect(result.payer).toBe(mockClientSigner.address);
});

it("should handle invalid signature format", async () => {
const requirements: PaymentRequirements = {
scheme: "exact",
Expand Down
17 changes: 13 additions & 4 deletions typescript/packages/mechanisms/svm/src/exact/facilitator/scheme.ts
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Original file line number Diff line number Diff line change
Expand Up @@ -33,6 +33,10 @@ import type { FacilitatorSvmSigner } from "../../signer";
import type { ExactSvmPayloadV2 } from "../../types";
import { decodeTransactionFromPayload, getTokenPayerFromTransaction } from "../../utils";

function toErrorMessage(error: unknown): string {
return error instanceof Error ? error.message : String(error);
}

/**
* SVM facilitator implementation for the Exact payment scheme.
*/
Expand Down Expand Up @@ -129,7 +133,8 @@ export class ExactSvmScheme implements SchemeNetworkFacilitator {
let transaction;
try {
transaction = decodeTransactionFromPayload(exactSvmPayload);
} catch {
} catch (error) {
console.warn("Failed to decode SVM transaction payload:", toErrorMessage(error));
return {
isValid: false,
invalidReason: "invalid_exact_svm_payload_transaction_could_not_be_decoded",
Expand Down Expand Up @@ -200,7 +205,8 @@ export class ExactSvmScheme implements SchemeNetworkFacilitator {
} else {
parsedTransfer = parseTransferCheckedInstruction2022(transferIx as never);
}
} catch {
} catch (error) {
console.warn("Failed to parse SVM transfer instruction:", toErrorMessage(error));
return {
isValid: false,
invalidReason: "invalid_exact_svm_payload_no_transfer_instruction",
Expand Down Expand Up @@ -248,10 +254,13 @@ export class ExactSvmScheme implements SchemeNetworkFacilitator {
payer,
};
}
} catch {
} catch (error) {
const message = toErrorMessage(error);
console.warn("Failed to derive expected recipient ATA during SVM verification:", message);
return {
isValid: false,
invalidReason: "invalid_exact_svm_payload_recipient_mismatch",
invalidReason: "invalid_exact_svm_payload_recipient_ata_lookup_failed",
invalidMessage: message,
payer,
};
}
Expand Down