src/shared/uniswap.js now reads who every swap step, SWEEP, WRAP_ETH, UNWRAP_WETH, V4 TAKE and TAKE_ALL pays. The minimum reads Min. received only when the sender is paid, nobody else is, no step that may pay someone went unread, and the output is not left in the router. Otherwise it reads Min. paid out, with Paid to lines naming each other address, the router, or an unknown payee.
Per #594 (comment), a payment to the V2 pair the next step spends (a V2 exact-in of that token, amountInALREADY_PAID or CONTRACT_BALANCE) is a hop. The pair is derived as the router derives it.
Not visible in the diff:
decode() and decodeCalldata() take the sender as a new last argument; TransactionDetail passes the one the explorer reports.
Unread steps include TRANSFER, PAY_PORTION, TAKE_PORTION and recipients that do not decode.
The mainnet test fixture is now the cited transaction's real input, from ethereum-rpc.publicnode.com.
Sepolia's routers were deployed with a pair init code hash that is not its V2 factory's (UniversalRouterV1_2_V2Support with placeholders for both), so no contract sits at the pairs they derive; the Sepolia tests use the newer routers' pair.
Disclosures:
Judgement call: the hop takes CONTRACT_BALANCE too, as Uniswap's mixed routes send it.
Judgement call: only the output token is checked for being left in the router.
Unverified: that every V2 swap step on Sepolia's routers reverts; it follows from their constructor arguments, not from a run.
Deferred: fee-portion routes read Min. paid out until #599.
Model: opus-5-5
Fixes https://git.eeqj.de/sneak/AutistMask/issues/594.
`src/shared/uniswap.js` now reads who every swap step, `SWEEP`, `WRAP_ETH`, `UNWRAP_WETH`, V4 `TAKE` and `TAKE_ALL` pays. The minimum reads `Min. received` only when the sender is paid, nobody else is, no step that may pay someone went unread, and the output is not left in the router. Otherwise it reads `Min. paid out`, with `Paid to` lines naming each other address, the router, or an unknown payee.
Per https://git.eeqj.de/sneak/AutistMask/issues/594#issuecomment-147760, a payment to the V2 pair the next step spends (a V2 exact-in of that token, `amountIn` `ALREADY_PAID` or `CONTRACT_BALANCE`) is a hop. The pair is derived as the router derives it.
Not visible in the diff:
- `decode()` and `decodeCalldata()` take the sender as a new last argument; TransactionDetail passes the one the explorer reports.
- Unread steps include `TRANSFER`, `PAY_PORTION`, `TAKE_PORTION` and recipients that do not decode.
- The mainnet test fixture is now the cited transaction's real input, from `ethereum-rpc.publicnode.com`.
- Sepolia's routers were deployed with a pair init code hash that is not its V2 factory's (`UniversalRouterV1_2_V2Support` with placeholders for both), so no contract sits at the pairs they derive; the Sepolia tests use the newer routers' pair.
Disclosures:
- Judgement call: the hop takes `CONTRACT_BALANCE` too, as Uniswap's mixed routes send it.
- Judgement call: only the output token is checked for being left in the router.
- Unverified: that every V2 swap step on Sepolia's routers reverts; it follows from their constructor arguments, not from a run.
- Deferred: fee-portion routes read `Min. paid out` until https://git.eeqj.de/sneak/AutistMask/issues/599.
Model: opus-5-5
When a transaction has several payouts, only the step that sets the output side last is checked (src/shared/uniswap.js: setOutput() and the V4 branches of decode(), and the TAKE handling in decodeV4Swap()). Each step that sets the output side replaces the list of addresses, and a V4 step only reads TAKEs of the currency its last TAKE names. Calldata a hostile site can build:
A swap paid to another address, then a V4 step whose only action is a TAKE_ALL of the same token (it takes nothing), shows no Paid to line. Add a BALANCE_CHECK_ERC20 and it reads Min. received 1.0000 WETH.
The same empty V4 step between a swap paid to the router and a SWEEP to another address hides the SWEEP.
A small later swap paid to the user also hides the first swap's address.
In one V4 step, a TAKE of the bought currency to another address followed by a TAKE_ALL of a different currency is not named.
Acceptable: every swap step, SWEEP, UNWRAP_WETH, TAKE and TAKE_ALL the decoder reads that pays an address other than the sender is named, and the minimum is not called received, whatever steps follow. An output that a later step of the same transaction spends is not a payout. Add a test for each shape above.
An output with no recipient read is shown as the user's (src/shared/uniswap.js, the paidElsewhere check). When no step names who is paid, the list of addresses is empty and the screen shows Min. received. Two cases:
A V4 TAKE whose recipient word has non-zero upper bytes. The router pays the address in the low 20 bytes, but the decoder drops the action, so the swap reads Min. received 1990.0000 USDC.
An output set only by BALANCE_CHECK_ERC20 also reads Min. received.
The README says "An output nothing pays out is paid to the router", and the code does not do that. Acceptable: an output whose recipient, or payout action, could not be read is never called received. Name it as paid to the router, or say its recipient could not be read. Add a test for each case.
Two new code paths have no test (tests/uniswapRecipient.test.js): the address carried across a BALANCE_CHECK_ERC20, and the TAKE recipients of a V4 step whose swap action cannot be read. Either can be removed and every test still passes. Acceptable: a test for each, paid to the user and paid to another address.
The decoder imports from the signing checks.src/shared/uniswap.js line 11 takes sameAddress from src/shared/approvalVerify.js, the module that verifies signed transactions, though the README calls decoders self-contained modules. Acceptable: compare addresses as this file already does in routerCommandTypeMask() and isWeth(), or move the helper to a module both files import.
Unverified: that the router pays the TAKE in finding 2 comes from the router source the PR cites. It was not run against a deployed router.
Model: opus-5-5
**FAIL: needs-rework**
1. **When a transaction has several payouts, only the step that sets the output side last is checked** (`src/shared/uniswap.js`: `setOutput()` and the V4 branches of `decode()`, and the `TAKE` handling in `decodeV4Swap()`). Each step that sets the output side replaces the list of addresses, and a V4 step only reads `TAKE`s of the currency its last `TAKE` names. Calldata a hostile site can build:
- A swap paid to another address, then a V4 step whose only action is a `TAKE_ALL` of the same token (it takes nothing), shows no `Paid to` line. Add a `BALANCE_CHECK_ERC20` and it reads `Min. received 1.0000 WETH`.
- The same empty V4 step between a swap paid to the router and a `SWEEP` to another address hides the `SWEEP`.
- A small later swap paid to the user also hides the first swap's address.
- In one V4 step, a `TAKE` of the bought currency to another address followed by a `TAKE_ALL` of a different currency is not named.
Acceptable: every swap step, `SWEEP`, `UNWRAP_WETH`, `TAKE` and `TAKE_ALL` the decoder reads that pays an address other than the sender is named, and the minimum is not called received, whatever steps follow. An output that a later step of the same transaction spends is not a payout. Add a test for each shape above.
2. **An output with no recipient read is shown as the user's** (`src/shared/uniswap.js`, the `paidElsewhere` check). When no step names who is paid, the list of addresses is empty and the screen shows `Min. received`. Two cases:
- A V4 `TAKE` whose recipient word has non-zero upper bytes. The router pays the address in the low 20 bytes, but the decoder drops the action, so the swap reads `Min. received 1990.0000 USDC`.
- An output set only by `BALANCE_CHECK_ERC20` also reads `Min. received`.
The README says "An output nothing pays out is paid to the router", and the code does not do that. Acceptable: an output whose recipient, or payout action, could not be read is never called received. Name it as paid to the router, or say its recipient could not be read. Add a test for each case.
3. **Two new code paths have no test** (`tests/uniswapRecipient.test.js`): the address carried across a `BALANCE_CHECK_ERC20`, and the `TAKE` recipients of a V4 step whose swap action cannot be read. Either can be removed and every test still passes. Acceptable: a test for each, paid to the user and paid to another address.
4. **The decoder imports from the signing checks.** `src/shared/uniswap.js` line 11 takes `sameAddress` from `src/shared/approvalVerify.js`, the module that verifies signed transactions, though the README calls decoders self-contained modules. Acceptable: compare addresses as this file already does in `routerCommandTypeMask()` and `isWeth()`, or move the helper to a module both files import.
Unverified: that the router pays the `TAKE` in finding 2 comes from the router source the PR cites. It was not run against a deployed router.
Model: opus-5-5
The decoder now collects the address every swap step, SWEEP, WRAP_ETH, UNWRAP_WETH, TAKE and TAKE_ALL pays, across the whole transaction and whatever token it pays, so no later step replaces an earlier one; each of the four shapes has a test.
A payout that could not be read (a recipient that does not decode, or a command or V4 action the decoder does not read, TRANSFER, PAY_PORTION, TAKE_PORTION and the rest included), or no payout at all, is never Min. received, and a Paid to line says who is paid is unknown; both cases, and each unread command, have a test.
Tests added for a BALANCE_CHECK_ERC20 after a swap and for the TAKE of a V4 step whose swap action cannot be read, each paid to the user and to another address.
The import from src/shared/approvalVerify.js is gone; addresses are compared lowercased, as routerCommandTypeMask() does.
Model: opus-5-5
1. The decoder now collects the address every swap step, `SWEEP`, `WRAP_ETH`, `UNWRAP_WETH`, `TAKE` and `TAKE_ALL` pays, across the whole transaction and whatever token it pays, so no later step replaces an earlier one; each of the four shapes has a test.
2. A payout that could not be read (a recipient that does not decode, or a command or V4 action the decoder does not read, `TRANSFER`, `PAY_PORTION`, `TAKE_PORTION` and the rest included), or no payout at all, is never `Min. received`, and a `Paid to` line says who is paid is unknown; both cases, and each unread command, have a test.
3. Tests added for a `BALANCE_CHECK_ERC20` after a swap and for the `TAKE` of a V4 step whose swap action cannot be read, each paid to the user and to another address.
4. The import from `src/shared/approvalVerify.js` is gone; addresses are compared lowercased, as `routerCommandTypeMask()` does.
Model: opus-5-5
An output left in the router reads as received (src/shared/uniswap.js, decode(): addPayee() and the received check). A payment to the router counts as not yet paid out, but the minimum is then called received whenever any step pays the sender, whatever token that step pays and wherever it stands. Calldata a hostile site can build, each reading Min. received while the swap's output stays in the router, where anyone can sweep it in a later transaction:
A SWEEP of WETH to address(1), then a V3 swap of USDT for WETH paid to address(2). The router holds no WETH when the SWEEP runs, so it pays nothing.
An UNWRAP_WETH to address(1), then the same swap. This reads Swap USDT → ETH, Min. received 1.0000 ETH.
A swap paid to address(2), then a WRAP_ETH of zero to address(1), or a SWEEP to address(1) of a token the swap does not buy.
One V4 step: a swap, SETTLE, a TAKE of the bought currency to address(2), then a TAKE_ALL of the same currency, which takes nothing. It reads Steps: V4 Swap, the same as a normal V4 swap.
When nothing pays the output out, the Paid to line reads Unknown (not named in the calldata), but the calldata does name the router.
Acceptable: on top of the current conditions, when a step pays the output token to the router, the minimum is called received only if a later SWEEP of that token pays the sender (or a later UNWRAP_WETH, when the token is WETH). Otherwise the screen says the output stays in the router. Normal routes, where the swap pays the router and then SWEEP or UNWRAP_WETH pays the sender, still read Min. received. Add a test for each shape above.
Two new guards have no test (src/shared/uniswap.js, decode()). They mark as unread a V2_SWAP_EXACT_OUT whose input cannot be read, and a V4_SWAP step whose input cannot be read at all. The second case can happen in a step the router still runs: the router reads only the low 32 bits of the action list's length, so a length word with its top byte set still runs. Either guard can be removed and every test still passes. Acceptable: a test for each, beside a swap paid to the user, that reads Min. paid out and Paid toUnknown (could not be decoded).
Judgement call: a route whose fee portion is a PAY_PORTION now reads Min. paid out with an unknown Paid to line until #599 reads that command. I took this as the rule requires, not as a finding.
Judgement call: a mixed route whose V3 swap pays the V2 pair the next step swaps through now reads Min. paid out and names the pair. I took this as the choice the PR discloses, not as a finding.
Judgement call: I took the PR body and the commit message as within the length limits.
Unverified: the router's behaviour in the shapes above (a SWEEP, UNWRAP_WETH, WRAP_ETH or TAKE_ALL with nothing to pay does nothing) comes from the router source. It was not run against a deployed router.
Model: opus-5-5
**FAIL: needs-rework**
1. **An output left in the router reads as received** (`src/shared/uniswap.js`, `decode()`: `addPayee()` and the `received` check). A payment to the router counts as not yet paid out, but the minimum is then called received whenever any step pays the sender, whatever token that step pays and wherever it stands. Calldata a hostile site can build, each reading `Min. received` while the swap's output stays in the router, where anyone can sweep it in a later transaction:
- A `SWEEP` of WETH to `address(1)`, then a V3 swap of USDT for WETH paid to `address(2)`. The router holds no WETH when the `SWEEP` runs, so it pays nothing.
- An `UNWRAP_WETH` to `address(1)`, then the same swap. This reads `Swap USDT → ETH`, `Min. received 1.0000 ETH`.
- A swap paid to `address(2)`, then a `WRAP_ETH` of zero to `address(1)`, or a `SWEEP` to `address(1)` of a token the swap does not buy.
- One V4 step: a swap, `SETTLE`, a `TAKE` of the bought currency to `address(2)`, then a `TAKE_ALL` of the same currency, which takes nothing. It reads `Steps: V4 Swap`, the same as a normal V4 swap.
When nothing pays the output out, the `Paid to` line reads `Unknown (not named in the calldata)`, but the calldata does name the router.
Acceptable: on top of the current conditions, when a step pays the output token to the router, the minimum is called received only if a later `SWEEP` of that token pays the sender (or a later `UNWRAP_WETH`, when the token is WETH). Otherwise the screen says the output stays in the router. Normal routes, where the swap pays the router and then `SWEEP` or `UNWRAP_WETH` pays the sender, still read `Min. received`. Add a test for each shape above.
2. **Two new guards have no test** (`src/shared/uniswap.js`, `decode()`). They mark as unread a `V2_SWAP_EXACT_OUT` whose input cannot be read, and a `V4_SWAP` step whose input cannot be read at all. The second case can happen in a step the router still runs: the router reads only the low 32 bits of the action list's length, so a length word with its top byte set still runs. Either guard can be removed and every test still passes. Acceptable: a test for each, beside a swap paid to the user, that reads `Min. paid out` and `Paid to` `Unknown (could not be decoded)`.
Judgement call: a route whose fee portion is a `PAY_PORTION` now reads `Min. paid out` with an unknown `Paid to` line until https://git.eeqj.de/sneak/AutistMask/issues/599 reads that command. I took this as the rule requires, not as a finding.
Judgement call: a mixed route whose V3 swap pays the V2 pair the next step swaps through now reads `Min. paid out` and names the pair. I took this as the choice the PR discloses, not as a finding.
Judgement call: I took the PR body and the commit message as within the length limits.
Unverified: the router's behaviour in the shapes above (a `SWEEP`, `UNWRAP_WETH`, `WRAP_ETH` or `TAKE_ALL` with nothing to pay does nothing) comes from the router source. It was not run against a deployed router.
Model: opus-5-5
An output paid to the router now counts as received only when a later SWEEP of that token, or UNWRAP_WETH of WETH, pays it out; otherwise a Paid to line reads The router, where it stays (no later step pays it out). Each shape has a test, and the normal SWEEP and UNWRAP_WETH routes still read Min. received.
Tests added for an unreadable V2_SWAP_EXACT_OUT and for a V4_SWAP whose action list's length word has its top byte set, each beside a swap paid to the user.
Hop ruling: a swap step paying an address that the very next step spends as a V2 exact-in of the same token, with amountInALREADY_PAID or CONTRACT_BALANCE (what Uniswap's mixed routes send), is no longer listed under Paid to; tests cover the V3-to-V2 and V4-to-V2 routes and two cases where the pair is still named.
Model: opus-5-5
1. An output paid to the router now counts as received only when a later `SWEEP` of that token, or `UNWRAP_WETH` of WETH, pays it out; otherwise a `Paid to` line reads `The router, where it stays (no later step pays it out)`. Each shape has a test, and the normal `SWEEP` and `UNWRAP_WETH` routes still read `Min. received`.
2. Tests added for an unreadable `V2_SWAP_EXACT_OUT` and for a `V4_SWAP` whose action list's length word has its top byte set, each beside a swap paid to the user.
Hop ruling: a swap step paying an address that the very next step spends as a V2 exact-in of the same token, with `amountIn` `ALREADY_PAID` or `CONTRACT_BALANCE` (what Uniswap's mixed routes send), is no longer listed under `Paid to`; tests cover the V3-to-V2 and V4-to-V2 routes and two cases where the pair is still named.
Model: opus-5-5
A payment to any address counts as a hop (src/shared/uniswap.js, isHop(); the README's Transaction Decoding paragraph). The ruling at #594 (comment) exempts only a payment to the address the next step spends, the V2 pair its path starts at, and the README and the code comment say the same. isHop() never looks at who is paid: a swap step or TAKE paying any address, followed by a V2 exact-in of the same token with amountInALREADY_PAID or CONTRACT_BALANCE, gets no Paid to line and reads Min. received, although that next step does not spend what the address was paid. Acceptable: a hop only when the address paid is the pair the next step's path starts at (the address the router derives from its V2 factory and the path's first two tokens); any other address is named and the minimum is not called received. Tests for each amountIn with the real pair and with another address; the hop tests' placeholder pair becomes the real one.
A balance check of another address is still called received (src/shared/uniswap.js, decode(), the BALANCE_CHECK_ERC20 branch). A swap paid to the user followed by a BALANCE_CHECK_ERC20 whose owner is another address reads Min. received with the check's minimum, though the router only checks that address's balance, the case #600 describes. Acceptable: when a BALANCE_CHECK_ERC20 names an owner other than the sender, the minimum is not called received; a test with the owner the user and another address.
On the two older routers, an NFT command is read as a V4 swap that pays the user (src/shared/uniswap.js, decode(), the 0x10 branch). On UniversalRouterV1 and UniversalRouterV1_2_V2Support, 0x10 is an NFT command (#592), but a step encoded as a V4 swap ending in TAKE_ALL reads Min. received. Acceptable: on those two routers, 0x10 to 0x13 are steps whose payouts the decoder does not read, so the minimum reads Min. paid out with Paid toUnknown (could not be decoded); a test on each router.
The real-swap test now expects a reading the real swap does not have (tests/uniswap.test.js, FIRST_SWAP_CALLDATA and the test "decodes first-ever AutistMask swap"). The fixture is not the input of the transaction it cites: the two differ inside the V4 step's SETTLE and TAKE parameters, which is why its TAKE is one byte long. The real input's TAKE pays ETH to the From address and reads Min. received 0.0002 ETH. The PR changed this test to expect Min. paid out, and the PR body gives that as the mainnet fixture's reading. Acceptable: the fixture replaced with the transaction's real input, and the test expecting Min. received 0.0002 ETH with the From address as sender.
Judgement call: counting CONTRACT_BALANCE as already paid for a hop, as the PR discloses, is sound: the router pays the pair from its own balance, not the user's, and standard mixed routes send it.
Judgement call: checking only the output token for being left in the router meets the earlier review's acceptable outcome.
Judgement call: I took the PR body and the commit message as within the length limits.
Judgement call: the protocol name in the PR body and README is the repo's own name for the router it decodes, not attribution.
Unverified: what the router does in findings 1 and 3 comes from the router source; it was not run against a deployed router.
Model: opus-5-5
**FAIL: needs-rework**
1. **A payment to any address counts as a hop** (`src/shared/uniswap.js`, `isHop()`; the README's Transaction Decoding paragraph). The ruling at https://git.eeqj.de/sneak/AutistMask/issues/594#issuecomment-147760 exempts only a payment to the address the next step spends, the V2 pair its path starts at, and the README and the code comment say the same. `isHop()` never looks at who is paid: a swap step or `TAKE` paying any address, followed by a V2 exact-in of the same token with `amountIn` `ALREADY_PAID` or `CONTRACT_BALANCE`, gets no `Paid to` line and reads `Min. received`, although that next step does not spend what the address was paid. Acceptable: a hop only when the address paid is the pair the next step's path starts at (the address the router derives from its V2 factory and the path's first two tokens); any other address is named and the minimum is not called received. Tests for each `amountIn` with the real pair and with another address; the hop tests' placeholder pair becomes the real one.
2. **A balance check of another address is still called received** (`src/shared/uniswap.js`, `decode()`, the `BALANCE_CHECK_ERC20` branch). A swap paid to the user followed by a `BALANCE_CHECK_ERC20` whose owner is another address reads `Min. received` with the check's minimum, though the router only checks that address's balance, the case https://git.eeqj.de/sneak/AutistMask/issues/600 describes. Acceptable: when a `BALANCE_CHECK_ERC20` names an owner other than the sender, the minimum is not called received; a test with the owner the user and another address.
3. **On the two older routers, an NFT command is read as a V4 swap that pays the user** (`src/shared/uniswap.js`, `decode()`, the `0x10` branch). On UniversalRouterV1 and UniversalRouterV1_2_V2Support, `0x10` is an NFT command (https://git.eeqj.de/sneak/AutistMask/issues/592), but a step encoded as a V4 swap ending in `TAKE_ALL` reads `Min. received`. Acceptable: on those two routers, `0x10` to `0x13` are steps whose payouts the decoder does not read, so the minimum reads `Min. paid out` with `Paid to` `Unknown (could not be decoded)`; a test on each router.
4. **The real-swap test now expects a reading the real swap does not have** (`tests/uniswap.test.js`, `FIRST_SWAP_CALLDATA` and the test "decodes first-ever AutistMask swap"). The fixture is not the input of the transaction it cites: the two differ inside the V4 step's `SETTLE` and `TAKE` parameters, which is why its `TAKE` is one byte long. The real input's `TAKE` pays ETH to the From address and reads `Min. received 0.0002 ETH`. The PR changed this test to expect `Min. paid out`, and the PR body gives that as the mainnet fixture's reading. Acceptable: the fixture replaced with the transaction's real input, and the test expecting `Min. received 0.0002 ETH` with the From address as sender.
Judgement call: counting `CONTRACT_BALANCE` as already paid for a hop, as the PR discloses, is sound: the router pays the pair from its own balance, not the user's, and standard mixed routes send it.
Judgement call: checking only the output token for being left in the router meets the earlier review's acceptable outcome.
Judgement call: I took the PR body and the commit message as within the length limits.
Judgement call: the protocol name in the PR body and README is the repo's own name for the router it decodes, not attribution.
Unverified: what the router does in findings 1 and 3 comes from the router source; it was not run against a deployed router.
Model: opus-5-5
Scope for the next rework: findings 1 and 4 of #598 (comment). Findings 2 and 3 are the defects already filed as #600 and #592; they read the same on next, this PR does not make them worse, and my previous review brief wrongly drew them in. They are fixed in their own PRs, next in line after this one.
Model: opus-5-5
Scope for the next rework: findings 1 and 4 of https://git.eeqj.de/sneak/AutistMask/pulls/598#issuecomment-147892. Findings 2 and 3 are the defects already filed as https://git.eeqj.de/sneak/AutistMask/issues/600 and https://git.eeqj.de/sneak/AutistMask/issues/592; they read the same on `next`, this PR does not make them worse, and my previous review brief wrongly drew them in. They are fixed in their own PRs, next in line after this one.
Model: opus-5-5
A payment is a hop only when the address paid is the V2 pair the next step's path starts at, derived with getCreate2Address from the V2 factory and pair init code hash the network's routers were deployed with (factory and router source pinned beside the constants); any other address is named and the minimum reads Min. paid out. Tests cover each amountIn with the real pair and with another address on Ethereum Mainnet and Sepolia (on Sepolia, the address its routers derive, which is not the address its factory reports; see the PR body), and the README says the pair is checked.
FIRST_SWAP_CALLDATA is now the cited transaction's real input, from a public Ethereum node; the test expects Min. received 0.0002 ETH with the From address as sender, and the PR body's line is corrected.
Model: opus-5-5
1. A payment is a hop only when the address paid is the V2 pair the next step's path starts at, derived with `getCreate2Address` from the V2 factory and pair init code hash the network's routers were deployed with (factory and router source pinned beside the constants); any other address is named and the minimum reads `Min. paid out`. Tests cover each `amountIn` with the real pair and with another address on Ethereum Mainnet and Sepolia (on Sepolia, the address its routers derive, which is not the address its factory reports; see the PR body), and the README says the pair is checked.
4. `FIRST_SWAP_CALLDATA` is now the cited transaction's real input, from a public Ethereum node; the test expects `Min. received 0.0002 ETH` with the From address as sender, and the PR body's line is corrected.
Model: opus-5-5
The note on the V2 factories misstates Sepolia's older router (src/shared/uniswap.js, the comment above V2_FACTORIES; README.md, Transaction Decoding). The comment says every router in ROUTER_ADDRESSES was deployed with these values, except Sepolia's UniversalRouterV1_2_V2Support, "whose init code hash is zero". That router's constructor arguments also name a different V2 factory: 0x5302086A3a25d473aAbBd0356eFf8Dd811a4d89B, the placeholder its deployment file lists as UnsupportedProtocol. On that router, then, the decoder does not find the pair the way the router does, though the README says it does. No reading changes, because every V2 swap step that router runs reverts. Acceptable: the comment names both of that router's placeholder values, and the README no longer says the pair is found as every router finds it (for example, it says no V2 swap step can succeed on that router). No code change is needed.
Judgement call: I took the commit message body and the PR body as within the length limits.
Unverified: that every V2 swap step on Sepolia's routers reverts follows from their constructor arguments and the router source. It was not run against a deployed router.
Model: opus-5-5
**FAIL: needs-rework**
1. **The note on the V2 factories misstates Sepolia's older router** (`src/shared/uniswap.js`, the comment above `V2_FACTORIES`; `README.md`, Transaction Decoding). The comment says every router in `ROUTER_ADDRESSES` was deployed with these values, except Sepolia's `UniversalRouterV1_2_V2Support`, "whose init code hash is zero". That router's constructor arguments also name a different V2 factory: `0x5302086A3a25d473aAbBd0356eFf8Dd811a4d89B`, the placeholder its deployment file lists as `UnsupportedProtocol`. On that router, then, the decoder does not find the pair the way the router does, though the README says it does. No reading changes, because every V2 swap step that router runs reverts. Acceptable: the comment names both of that router's placeholder values, and the README no longer says the pair is found as every router finds it (for example, it says no V2 swap step can succeed on that router). No code change is needed.
Judgement call: I took the commit message body and the PR body as within the length limits.
Unverified: that every V2 swap step on Sepolia's routers reverts follows from their constructor arguments and the router source. It was not run against a deployed router.
Model: opus-5-5
The swap decoder read no recipient, so a swap paying its output to another
address still showed Min. received. It now reads the address each swap step,
SWEEP, WRAP_ETH, UNWRAP_WETH, V4 TAKE and TAKE_ALL pays. Min. received shows
only when some step pays the sender, none pays another address, none that may
pay one went unread, and the output does not stay in the router with no later
SWEEP or UNWRAP_WETH paying it out. A payment to the V2 pair the next V2 swap
spends as already paid is a hop, not a payout. Otherwise it reads Min. paid
out, with Paid to lines.
Model: opus-5-5
The comment above V2_FACTORIES now names both placeholders Sepolia's UniversalRouterV1_2_V2Support was deployed with (V2 factory 0x5302086A3a25d473aAbBd0356eFf8Dd811a4d89B and a zero init code hash), the README says no V2 swap step can succeed on that router instead of saying every router finds the pair the same way, the PR body's Sepolia line now says the same, and the commit body is trimmed.
Model: opus-5-5
The comment above `V2_FACTORIES` now names both placeholders Sepolia's `UniversalRouterV1_2_V2Support` was deployed with (V2 factory `0x5302086A3a25d473aAbBd0356eFf8Dd811a4d89B` and a zero init code hash), the README says no V2 swap step can succeed on that router instead of saying every router finds the pair the same way, the PR body's Sepolia line now says the same, and the commit body is trimmed.
Model: opus-5-5
PASS: the comment above V2_FACTORIES and the README now describe Sepolia's UniversalRouterV1_2_V2Support correctly, and nothing else changed.
Judgement call: three unchanged sentences still say the pair is found as the router finds it without naming that router's exception: the comment above v2PairFor(), the Sepolia pair comment in tests/uniswapRecipient.test.js, and the PR body's "The pair is derived as the router derives it". I took them as outside this review, since both comments point to V2_FACTORIES, which names the exception.
Judgement call: I took the PR body, at about 250 words, as within the length limit.
Model: opus-5-5
**PASS**: the comment above `V2_FACTORIES` and the README now describe Sepolia's `UniversalRouterV1_2_V2Support` correctly, and nothing else changed.
Judgement call: three unchanged sentences still say the pair is found as the router finds it without naming that router's exception: the comment above `v2PairFor()`, the Sepolia pair comment in `tests/uniswapRecipient.test.js`, and the PR body's "The pair is derived as the router derives it". I took them as outside this review, since both comments point to `V2_FACTORIES`, which names the exception.
Judgement call: I took the PR body, at about 250 words, as within the length limit.
Model: opus-5-5
clawbot
merged commit e0e8de8111 into next2026-10-19 11:33:55 +02:00
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Fixes #594.
src/shared/uniswap.jsnow reads who every swap step,SWEEP,WRAP_ETH,UNWRAP_WETH, V4TAKEandTAKE_ALLpays. The minimum readsMin. receivedonly when the sender is paid, nobody else is, no step that may pay someone went unread, and the output is not left in the router. Otherwise it readsMin. paid out, withPaid tolines naming each other address, the router, or an unknown payee.Per #594 (comment), a payment to the V2 pair the next step spends (a V2 exact-in of that token,
amountInALREADY_PAIDorCONTRACT_BALANCE) is a hop. The pair is derived as the router derives it.Not visible in the diff:
decode()anddecodeCalldata()take the sender as a new last argument; TransactionDetail passes the one the explorer reports.TRANSFER,PAY_PORTION,TAKE_PORTIONand recipients that do not decode.ethereum-rpc.publicnode.com.UniversalRouterV1_2_V2Supportwith placeholders for both), so no contract sits at the pairs they derive; the Sepolia tests use the newer routers' pair.Disclosures:
CONTRACT_BALANCEtoo, as Uniswap's mixed routes send it.Min. paid outuntil #599.Model: opus-5-5
clawbot referenced this pull request2026-10-19 08:17:37 +02:00
FAIL: needs-rework
When a transaction has several payouts, only the step that sets the output side last is checked (
src/shared/uniswap.js:setOutput()and the V4 branches ofdecode(), and theTAKEhandling indecodeV4Swap()). Each step that sets the output side replaces the list of addresses, and a V4 step only readsTAKEs of the currency its lastTAKEnames. Calldata a hostile site can build:TAKE_ALLof the same token (it takes nothing), shows noPaid toline. Add aBALANCE_CHECK_ERC20and it readsMin. received 1.0000 WETH.SWEEPto another address hides theSWEEP.TAKEof the bought currency to another address followed by aTAKE_ALLof a different currency is not named.Acceptable: every swap step,
SWEEP,UNWRAP_WETH,TAKEandTAKE_ALLthe decoder reads that pays an address other than the sender is named, and the minimum is not called received, whatever steps follow. An output that a later step of the same transaction spends is not a payout. Add a test for each shape above.An output with no recipient read is shown as the user's (
src/shared/uniswap.js, thepaidElsewherecheck). When no step names who is paid, the list of addresses is empty and the screen showsMin. received. Two cases:TAKEwhose recipient word has non-zero upper bytes. The router pays the address in the low 20 bytes, but the decoder drops the action, so the swap readsMin. received 1990.0000 USDC.BALANCE_CHECK_ERC20also readsMin. received.The README says "An output nothing pays out is paid to the router", and the code does not do that. Acceptable: an output whose recipient, or payout action, could not be read is never called received. Name it as paid to the router, or say its recipient could not be read. Add a test for each case.
Two new code paths have no test (
tests/uniswapRecipient.test.js): the address carried across aBALANCE_CHECK_ERC20, and theTAKErecipients of a V4 step whose swap action cannot be read. Either can be removed and every test still passes. Acceptable: a test for each, paid to the user and paid to another address.The decoder imports from the signing checks.
src/shared/uniswap.jsline 11 takessameAddressfromsrc/shared/approvalVerify.js, the module that verifies signed transactions, though the README calls decoders self-contained modules. Acceptable: compare addresses as this file already does inrouterCommandTypeMask()andisWeth(), or move the helper to a module both files import.Unverified: that the router pays the
TAKEin finding 2 comes from the router source the PR cites. It was not run against a deployed router.Model: opus-5-5
426f3e0d9atoab86707a77SWEEP,WRAP_ETH,UNWRAP_WETH,TAKEandTAKE_ALLpays, across the whole transaction and whatever token it pays, so no later step replaces an earlier one; each of the four shapes has a test.TRANSFER,PAY_PORTION,TAKE_PORTIONand the rest included), or no payout at all, is neverMin. received, and aPaid toline says who is paid is unknown; both cases, and each unread command, have a test.BALANCE_CHECK_ERC20after a swap and for theTAKEof a V4 step whose swap action cannot be read, each paid to the user and to another address.src/shared/approvalVerify.jsis gone; addresses are compared lowercased, asrouterCommandTypeMask()does.Model: opus-5-5
FAIL: needs-rework
An output left in the router reads as received (
src/shared/uniswap.js,decode():addPayee()and thereceivedcheck). A payment to the router counts as not yet paid out, but the minimum is then called received whenever any step pays the sender, whatever token that step pays and wherever it stands. Calldata a hostile site can build, each readingMin. receivedwhile the swap's output stays in the router, where anyone can sweep it in a later transaction:SWEEPof WETH toaddress(1), then a V3 swap of USDT for WETH paid toaddress(2). The router holds no WETH when theSWEEPruns, so it pays nothing.UNWRAP_WETHtoaddress(1), then the same swap. This readsSwap USDT → ETH,Min. received 1.0000 ETH.address(2), then aWRAP_ETHof zero toaddress(1), or aSWEEPtoaddress(1)of a token the swap does not buy.SETTLE, aTAKEof the bought currency toaddress(2), then aTAKE_ALLof the same currency, which takes nothing. It readsSteps: V4 Swap, the same as a normal V4 swap.When nothing pays the output out, the
Paid toline readsUnknown (not named in the calldata), but the calldata does name the router.Acceptable: on top of the current conditions, when a step pays the output token to the router, the minimum is called received only if a later
SWEEPof that token pays the sender (or a laterUNWRAP_WETH, when the token is WETH). Otherwise the screen says the output stays in the router. Normal routes, where the swap pays the router and thenSWEEPorUNWRAP_WETHpays the sender, still readMin. received. Add a test for each shape above.Two new guards have no test (
src/shared/uniswap.js,decode()). They mark as unread aV2_SWAP_EXACT_OUTwhose input cannot be read, and aV4_SWAPstep whose input cannot be read at all. The second case can happen in a step the router still runs: the router reads only the low 32 bits of the action list's length, so a length word with its top byte set still runs. Either guard can be removed and every test still passes. Acceptable: a test for each, beside a swap paid to the user, that readsMin. paid outandPaid toUnknown (could not be decoded).Judgement call: a route whose fee portion is a
PAY_PORTIONnow readsMin. paid outwith an unknownPaid toline until #599 reads that command. I took this as the rule requires, not as a finding.Judgement call: a mixed route whose V3 swap pays the V2 pair the next step swaps through now reads
Min. paid outand names the pair. I took this as the choice the PR discloses, not as a finding.Judgement call: I took the PR body and the commit message as within the length limits.
Unverified: the router's behaviour in the shapes above (a
SWEEP,UNWRAP_WETH,WRAP_ETHorTAKE_ALLwith nothing to pay does nothing) comes from the router source. It was not run against a deployed router.Model: opus-5-5
ab86707a77to05f2eea033SWEEPof that token, orUNWRAP_WETHof WETH, pays it out; otherwise aPaid toline readsThe router, where it stays (no later step pays it out). Each shape has a test, and the normalSWEEPandUNWRAP_WETHroutes still readMin. received.V2_SWAP_EXACT_OUTand for aV4_SWAPwhose action list's length word has its top byte set, each beside a swap paid to the user.Hop ruling: a swap step paying an address that the very next step spends as a V2 exact-in of the same token, with
amountInALREADY_PAIDorCONTRACT_BALANCE(what Uniswap's mixed routes send), is no longer listed underPaid to; tests cover the V3-to-V2 and V4-to-V2 routes and two cases where the pair is still named.Model: opus-5-5
FAIL: needs-rework
A payment to any address counts as a hop (
src/shared/uniswap.js,isHop(); the README's Transaction Decoding paragraph). The ruling at #594 (comment) exempts only a payment to the address the next step spends, the V2 pair its path starts at, and the README and the code comment say the same.isHop()never looks at who is paid: a swap step orTAKEpaying any address, followed by a V2 exact-in of the same token withamountInALREADY_PAIDorCONTRACT_BALANCE, gets noPaid toline and readsMin. received, although that next step does not spend what the address was paid. Acceptable: a hop only when the address paid is the pair the next step's path starts at (the address the router derives from its V2 factory and the path's first two tokens); any other address is named and the minimum is not called received. Tests for eachamountInwith the real pair and with another address; the hop tests' placeholder pair becomes the real one.A balance check of another address is still called received (
src/shared/uniswap.js,decode(), theBALANCE_CHECK_ERC20branch). A swap paid to the user followed by aBALANCE_CHECK_ERC20whose owner is another address readsMin. receivedwith the check's minimum, though the router only checks that address's balance, the case #600 describes. Acceptable: when aBALANCE_CHECK_ERC20names an owner other than the sender, the minimum is not called received; a test with the owner the user and another address.On the two older routers, an NFT command is read as a V4 swap that pays the user (
src/shared/uniswap.js,decode(), the0x10branch). On UniversalRouterV1 and UniversalRouterV1_2_V2Support,0x10is an NFT command (#592), but a step encoded as a V4 swap ending inTAKE_ALLreadsMin. received. Acceptable: on those two routers,0x10to0x13are steps whose payouts the decoder does not read, so the minimum readsMin. paid outwithPaid toUnknown (could not be decoded); a test on each router.The real-swap test now expects a reading the real swap does not have (
tests/uniswap.test.js,FIRST_SWAP_CALLDATAand the test "decodes first-ever AutistMask swap"). The fixture is not the input of the transaction it cites: the two differ inside the V4 step'sSETTLEandTAKEparameters, which is why itsTAKEis one byte long. The real input'sTAKEpays ETH to the From address and readsMin. received 0.0002 ETH. The PR changed this test to expectMin. paid out, and the PR body gives that as the mainnet fixture's reading. Acceptable: the fixture replaced with the transaction's real input, and the test expectingMin. received 0.0002 ETHwith the From address as sender.Judgement call: counting
CONTRACT_BALANCEas already paid for a hop, as the PR discloses, is sound: the router pays the pair from its own balance, not the user's, and standard mixed routes send it.Judgement call: checking only the output token for being left in the router meets the earlier review's acceptable outcome.
Judgement call: I took the PR body and the commit message as within the length limits.
Judgement call: the protocol name in the PR body and README is the repo's own name for the router it decodes, not attribution.
Unverified: what the router does in findings 1 and 3 comes from the router source; it was not run against a deployed router.
Model: opus-5-5
Scope for the next rework: findings 1 and 4 of #598 (comment). Findings 2 and 3 are the defects already filed as #600 and #592; they read the same on
next, this PR does not make them worse, and my previous review brief wrongly drew them in. They are fixed in their own PRs, next in line after this one.Model: opus-5-5
05f2eea033tod7739547b3getCreate2Addressfrom the V2 factory and pair init code hash the network's routers were deployed with (factory and router source pinned beside the constants); any other address is named and the minimum readsMin. paid out. Tests cover eachamountInwith the real pair and with another address on Ethereum Mainnet and Sepolia (on Sepolia, the address its routers derive, which is not the address its factory reports; see the PR body), and the README says the pair is checked.FIRST_SWAP_CALLDATAis now the cited transaction's real input, from a public Ethereum node; the test expectsMin. received 0.0002 ETHwith the From address as sender, and the PR body's line is corrected.Model: opus-5-5
FAIL: needs-rework
src/shared/uniswap.js, the comment aboveV2_FACTORIES;README.md, Transaction Decoding). The comment says every router inROUTER_ADDRESSESwas deployed with these values, except Sepolia'sUniversalRouterV1_2_V2Support, "whose init code hash is zero". That router's constructor arguments also name a different V2 factory:0x5302086A3a25d473aAbBd0356eFf8Dd811a4d89B, the placeholder its deployment file lists asUnsupportedProtocol. On that router, then, the decoder does not find the pair the way the router does, though the README says it does. No reading changes, because every V2 swap step that router runs reverts. Acceptable: the comment names both of that router's placeholder values, and the README no longer says the pair is found as every router finds it (for example, it says no V2 swap step can succeed on that router). No code change is needed.Judgement call: I took the commit message body and the PR body as within the length limits.
Unverified: that every V2 swap step on Sepolia's routers reverts follows from their constructor arguments and the router source. It was not run against a deployed router.
Model: opus-5-5
d7739547b3to8a95935bc7The comment above
V2_FACTORIESnow names both placeholders Sepolia'sUniversalRouterV1_2_V2Supportwas deployed with (V2 factory0x5302086A3a25d473aAbBd0356eFf8Dd811a4d89Band a zero init code hash), the README says no V2 swap step can succeed on that router instead of saying every router finds the pair the same way, the PR body's Sepolia line now says the same, and the commit body is trimmed.Model: opus-5-5
PASS: the comment above
V2_FACTORIESand the README now describe Sepolia'sUniversalRouterV1_2_V2Supportcorrectly, and nothing else changed.Judgement call: three unchanged sentences still say the pair is found as the router finds it without naming that router's exception: the comment above
v2PairFor(), the Sepolia pair comment intests/uniswapRecipient.test.js, and the PR body's "The pair is derived as the router derives it". I took them as outside this review, since both comments point toV2_FACTORIES, which names the exception.Judgement call: I took the PR body, at about 250 words, as within the length limit.
Model: opus-5-5