From c2844f16de9f3d3b954b53acaa17806d45758f21 Mon Sep 17 00:00:00 2001
From: Matt Holtzman <matt.holtzman@gmail.com>
Date: Wed, 25 Aug 2021 08:48:41 -0400
Subject: [PATCH] implement eip-1559 support for Trezors

---
 main/signers/hot/HotSigner/worker.js        |  1 +
 main/signers/trezor-connect/Trezor/index.js | 40 +++++++++++++--------
 main/transaction/index.ts                   |  3 +-
 test/main/transaction/index.test.js         | 30 ++++++++++++++--
 4 files changed, 57 insertions(+), 17 deletions(-)

diff --git a/main/signers/hot/HotSigner/worker.js b/main/signers/hot/HotSigner/worker.js
index d7dadd580..1c360cfb4 100644
--- a/main/signers/hot/HotSigner/worker.js
+++ b/main/signers/hot/HotSigner/worker.js
@@ -50,6 +50,7 @@ class HotSignerWorker {
   signTransaction (key, rawTx, pseudoCallback) {
     sign(rawTx, tx => {
       const signedTx = tx.sign(key)
+
       const serialized = signedTx.serialize().toString('hex')
 
       pseudoCallback(null, addHexPrefix(serialized))
diff --git a/main/signers/trezor-connect/Trezor/index.js b/main/signers/trezor-connect/Trezor/index.js
index e69d513a2..d01965e5d 100644
--- a/main/signers/trezor-connect/Trezor/index.js
+++ b/main/signers/trezor-connect/Trezor/index.js
@@ -208,27 +208,39 @@ class Trezor extends Signer {
     })
   }
 
-  _normalizeTransaction (rawTx) {
-    return {
-      nonce: this.normalize(rawTx.nonce),
-      gasPrice: this.normalize(rawTx.gasPrice),
-      gasLimit: this.normalize(rawTx.gasLimit),
-      to: this.normalize(rawTx.to),
-      value: this.normalize(rawTx.value),
-      data: this.normalize(rawTx.data),
-      chainId: utils.hexToNumber(rawTx.chainId)
+  _normalizeTransaction (chainId, tx) {
+    const txJson = tx.toJSON()
+
+    const unsignedTx = {
+      nonce: this.normalize(txJson.nonce),
+      gasLimit: this.normalize(txJson.gasLimit),
+      to: this.normalize(txJson.to),
+      value: this.normalize(txJson.value),
+      data: this.normalize(txJson.data),
+      chainId: utils.hexToNumber(chainId)
     }
+
+    const optionalFields = ['gasPrice', 'maxFeePerGas', 'maxPriorityFeePerGas']
+
+    optionalFields.forEach(field => {
+      if (txJson[field]) {
+        unsignedTx[field] = this.normalize(txJson[field])
+      }
+    })
+
+    return unsignedTx
   }
 
   signTransaction (index, rawTx, cb) {
-    // as of 08-05-2021 Trezor doesn't support EIP-1559 transactions
-    const legacyTx = londonToLegacy(rawTx)
+    const compatibility = signerCompatibility(rawTx, this.summary())
+    const compatibleTx = compatibility.compatible ? { ...rawTx } : londonToLegacy(rawTx)
 
-    const trezorTx = this._normalizeTransaction(legacyTx)
-    const path = this.getPath(index)
 
-    sign(legacyTx, () => {
+    sign(compatibleTx, () => {
       return new Promise((resolve, reject) => {
+        const trezorTx = this._normalizeTransaction(tx)
+        const path = this.getPath(index)
+
         flex.rpc('trezor.ethereumSignTransaction', this.device.path, path, trezorTx, (err, result) => {
           return err
             ? reject(err)
diff --git a/main/transaction/index.ts b/main/transaction/index.ts
index 367f81780..eae989437 100644
--- a/main/transaction/index.ts
+++ b/main/transaction/index.ts
@@ -8,6 +8,7 @@ const londonHardforkSigners: SignerCompatibilityByVersion = {
   seed: () => true,
   ring: () => true,
   ledger: version => version.major >= 2 || (version.major >= 1 && version.minor >= 9),
+  trezor: version => version.major >= 3 || (version.major >= 2 && version.minor >= 4 && version.patch >= 2),
   lattice: version =>  version.major >= 1 || version.minor >= 11
 }
 
@@ -87,7 +88,7 @@ function usesBaseFee (rawTx: RawTransaction) {
 
 function populate (rawTx: RawTransaction, chainConfig: Common, gas: any): TransactionData {
   const txData: TransactionData = { ...rawTx }
-  
+
   if (chainConfig.isActivatedEIP(1559)) {
     txData.type = '0x2'
 
diff --git a/test/main/transaction/index.test.js b/test/main/transaction/index.test.js
index 74ed8a4c0..097b17eb5 100644
--- a/test/main/transaction/index.test.js
+++ b/test/main/transaction/index.test.js
@@ -118,8 +118,8 @@ describe('#signerCompatibility', () => {
     expect(compatibility.compatible).toBe(true)
   })
 
-  it('is not compatible for eip-1559 transactions on Trezor signers', () => {
-    const appVersion = { major: 1, minor: 1, patch: 1 }
+  it('is not compatible for eip-1559 transactions on Trezor signers using firmware prior to 2.4.2', () => {
+    const appVersion = { major: 2, minor: 3, patch: 1 }
     const tx = {
       type: '0x2'
     }
@@ -130,6 +130,32 @@ describe('#signerCompatibility', () => {
     expect(compatibility.tx).toBe('london')
     expect(compatibility.compatible).toBe(false)
   })
+
+  it('is compatible for eip-1559 transactions on Trezor signers using firmware 2.4.2+', () => {
+    const appVersion = { major: 2, minor: 4, patch: 3 }
+    const tx = {
+      type: '0x2'
+    }
+
+    const compatibility = signerCompatibility(tx, { type: 'trezor', appVersion })
+
+    expect(compatibility.signer).toBe('trezor')
+    expect(compatibility.tx).toBe('london')
+    expect(compatibility.compatible).toBe(true)
+  })
+
+  it('is compatible for eip-1559 transactions on Trezor signers using firmware 3.x', () => {
+    const appVersion = { major: 3, minor: 2, patch: 4 }
+    const tx = {
+      type: '0x2'
+    }
+
+    const compatibility = signerCompatibility(tx, { type: 'trezor', appVersion })
+
+    expect(compatibility.signer).toBe('trezor')
+    expect(compatibility.tx).toBe('london')
+    expect(compatibility.compatible).toBe(true)
+  })
 })
 
 describe('#londonToLegacy', () => {