From a25e14cecb8b5b6c23990c1fd2b4516323289d6c Mon Sep 17 00:00:00 2001
From: 0xDeon <110722148+0xDeon@users.noreply.github.com>
Date: Fri, 6 Nov 2026 15:12:31 +0100
Subject: [PATCH] fix(dapp): let phantom's lighthouse guards through the
 cash-out deposit check

#157 fixed the chain submit route only. The cash-out deposit has its own submit, which checked
the signed bytes as they came from the wallet, so a Phantom user's swap-then-cash-out sent the
swap and then refused the deposit: "calls a program a USDC deposit does not need".

The deposit check now reads the same guard-free copy, and sends what the wallet signed. A test
now fails on any check that reads raw signed Solana bytes, so a third route can't miss it.
---
 .../solana-signed-checks-guarded.test.ts      | 44 +++++++++++++++++++
 .../__tests__/weave-deposit-solana.test.ts    | 34 ++++++++++++++
 apps/dapp/lib/weave/deposit/solana.ts         |  7 ++-
 3 files changed, 84 insertions(+), 1 deletion(-)
 create mode 100644 apps/dapp/lib/__tests__/solana-signed-checks-guarded.test.ts

diff --git a/apps/dapp/lib/__tests__/solana-signed-checks-guarded.test.ts b/apps/dapp/lib/__tests__/solana-signed-checks-guarded.test.ts
new file mode 100644
index 00000000..5f6b35b6
--- /dev/null
+++ b/apps/dapp/lib/__tests__/solana-signed-checks-guarded.test.ts
@@ -0,0 +1,44 @@
+import { readdirSync, readFileSync, statSync } from 'node:fs'
+import { join, relative } from 'node:path'
+
+import { describe, expect, it } from 'vitest'
+
+const ROOT = join(__dirname, '..', '..')
+
+function sources(dir: string): string[] {
+  return readdirSync(dir).flatMap((name) => {
+    const path = join(dir, name)
+    if (statSync(path).isDirectory()) {
+      return name === 'node_modules' || name === '__tests__' || name.startsWith('.')
+        ? []
+        : sources(path)
+    }
+    return /\.tsx?$/.test(name) ? [path] : []
+  })
+}
+
+/** Signed Solana bytes handed to a check as they came from the wallet, guards and all. */
+const RAW_SIGNED = /transaction:\s*[\w.]*\bsignedTransaction\b/
+
+describe('every check of a signed Solana transaction', () => {
+  it('first leaves out the wallet’s own Lighthouse guards', () => {
+    // Phantom adds them before signing. A check that reads the raw bytes refuses every Phantom user,
+    // as the cash-out deposit did on 6 November after the chain submit route was fixed alone.
+    const raw = [join(ROOT, 'app'), join(ROOT, 'lib')]
+      .flatMap(sources)
+      .filter((file) => RAW_SIGNED.test(readFileSync(file, 'utf8')))
+      .map((file) => relative(ROOT, file))
+    expect(raw).toEqual([])
+  })
+
+  it('would have caught the two places that read them raw', () => {
+    expect(RAW_SIGNED.test("{ family: 'solana', transaction: signed.signedTransaction }")).toBe(
+      true
+    )
+    expect(
+      RAW_SIGNED.test(
+        "{ family: 'solana', transaction: withoutWalletGuards(signed.signedTransaction) }"
+      )
+    ).toBe(false)
+  })
+})
diff --git a/apps/dapp/lib/__tests__/weave-deposit-solana.test.ts b/apps/dapp/lib/__tests__/weave-deposit-solana.test.ts
index cbcd80f3..d8a18dc9 100644
--- a/apps/dapp/lib/__tests__/weave-deposit-solana.test.ts
+++ b/apps/dapp/lib/__tests__/weave-deposit-solana.test.ts
@@ -627,6 +627,40 @@ describe('submit', () => {
     expect(fetchMock).not.toHaveBeenCalled()
   })
 
+  /** What Phantom adds before signing: a Lighthouse assertion on the signer's own account. */
+  const lighthouse: Instruction = {
+    programAddress: 'L2TExMFKdjpN9kozasaurPirfHy9P8sbXoAN1qA3S95',
+    accounts: [{ address: ACCOUNT, role: AccountRole.READONLY }],
+    data: Uint8Array.from([5, 0, 1]),
+  }
+
+  it('sends a deposit Phantom guarded, exactly as the wallet signed it', async () => {
+    const fetchMock = stubRpc()
+    const guarded = signed(compile([createAta(), transfer(), lighthouse]))
+    const result = await solanaDeposit.submit(
+      { family: 'solana', signedTransaction: guarded },
+      EXPECTATION
+    )
+    expect(result.ok).toBe(true)
+    const sent = fetchMock.mock.calls
+      .map(
+        ([, init]) =>
+          JSON.parse(String((init as RequestInit).body)) as { method: string; params: unknown[] }
+      )
+      .find((call) => call.method === 'sendTransaction')
+    expect(sent?.params[0]).toBe(guarded)
+  })
+
+  it('still refuses any other program a wallet adds beside the guard', async () => {
+    const fetchMock = stubRpc()
+    const other: Instruction = { programAddress: OTHER, accounts: [], data: Uint8Array.from([1]) }
+    const tampered = signed(compile([createAta(), transfer(), lighthouse, other]))
+    await expect(
+      solanaDeposit.submit({ family: 'solana', signedTransaction: tampered }, EXPECTATION)
+    ).rejects.toThrow(/does not need/)
+    expect(fetchMock).not.toHaveBeenCalled()
+  })
+
   it('refuses another family without sending', async () => {
     const fetchMock = stubRpc()
     const result = await solanaDeposit.submit({ family: 'near', hashes: ['x'] }, EXPECTATION)
diff --git a/apps/dapp/lib/weave/deposit/solana.ts b/apps/dapp/lib/weave/deposit/solana.ts
index 04d7cde2..fcca7fd6 100644
--- a/apps/dapp/lib/weave/deposit/solana.ts
+++ b/apps/dapp/lib/weave/deposit/solana.ts
@@ -32,6 +32,7 @@ import {
 import { venueFetch } from '../../chains/solana/http'
 import { createSolanaSubmit, explorerUrl, feePayerSignature } from '../../chains/solana/submit'
 import { SOLANA_TOKENS } from '../../chains/solana/tokens'
+import { withoutWalletGuards } from '../../chains/solana/wallet-guards'
 import {
   ChainActionRefused,
   tokenBySymbol,
@@ -416,7 +417,11 @@ async function submit(
   if (signed.family !== 'solana') {
     return { ok: false, error: 'That is not a Solana transaction, so nothing was sent.' }
   }
-  assertSafe({ family: 'solana', transaction: signed.signedTransaction }, expectation)
+  // Phantom's Lighthouse guards are its own and only make the transfer fail; the rest is checked.
+  assertSafe(
+    { family: 'solana', transaction: withoutWalletGuards(signed.signedTransaction) },
+    expectation
+  )
   const hash = feePayerSignature(signed.signedTransaction)
   if (hash === undefined) {
     return {