From 48562ccfc7e88372bbe3669424a8d36f76999d59 Mon Sep 17 00:00:00 2001
From: pscott <scott.piriou@ledger.fr>
Date: Thu, 15 Apr 2021 15:25:46 +0200
Subject: [PATCH 01/23] Add TransactionType and adapt parser to parse them

---
 src_common/ethUstream.c | 7 +++++++
 src_common/ethUstream.h | 7 +++++++
 2 files changed, 14 insertions(+)

diff --git a/src_common/ethUstream.c b/src_common/ethUstream.c
index 9ddf672..a97a418 100644
--- a/src_common/ethUstream.c
+++ b/src_common/ethUstream.c
@@ -263,7 +263,14 @@ static parserStatus_e processTxInternal(txContext_t *context) {
         if (context->commandLength == 0) {
             return USTREAM_PROCESSING;
         }
+        // EIP 2718: TransactionType might be present before the TransactionPayload.
+        if (*context->workBuffer > 0x00 && *context->workBuffer < 0x7f) {
+            context->txType = *context->workBuffer;
+            context->workBuffer++;
+            PRINTF("TX TYPE: %u\n", context->txType);
+        }
         if (!context->processingField) {
+            PRINTF("PROCESSING FIELD\n");
             bool canDecode = false;
             uint32_t offset;
             while (context->commandLength != 0) {
diff --git a/src_common/ethUstream.h b/src_common/ethUstream.h
index ff5c28e..24cbaa0 100644
--- a/src_common/ethUstream.h
+++ b/src_common/ethUstream.h
@@ -53,6 +53,12 @@ typedef enum rlpTxField_e {
     TX_RLP_DONE
 } rlpTxField_e;
 
+// EIP 2718 TransactionType
+typedef enum txType_e {
+    LegacyTransaction = 1,
+    BerlinTransaction = 2
+} txType_e;
+
 typedef enum parserStatus_e {
     USTREAM_PROCESSING,
     USTREAM_SUSPENDED,
@@ -93,6 +99,7 @@ typedef struct txContext_t {
     ustreamProcess_t customProcessor;
     txContent_t *content;
     void *extra;
+    uint8_t txType;
 } txContext_t;
 
 void initTx(txContext_t *context,

From 3faa172ec2748f655c64444c624a0b08739045ad Mon Sep 17 00:00:00 2001
From: pscott <scott.piriou@ledger.fr>
Date: Thu, 15 Apr 2021 15:36:21 +0200
Subject: [PATCH 02/23] Add MAX and MIN tx types

---
 src_common/ethUstream.c | 6 +++++-
 src_common/ethUstream.h | 6 ++++--
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/src_common/ethUstream.c b/src_common/ethUstream.c
index a97a418..18cd896 100644
--- a/src_common/ethUstream.c
+++ b/src_common/ethUstream.c
@@ -265,9 +265,13 @@ static parserStatus_e processTxInternal(txContext_t *context) {
         }
         // EIP 2718: TransactionType might be present before the TransactionPayload.
         if (*context->workBuffer > 0x00 && *context->workBuffer < 0x7f) {
+            PRINTF("TX TYPE: %u\n", context->txType);
+            if (*context->workBuffer < MIN_TX_TYPE || *context->workBuffer > MAX_TX_TYPE ) {
+                PRINTF("Transaction type not supported\n");
+                return USTREAM_FAULT;
+            }
             context->txType = *context->workBuffer;
             context->workBuffer++;
-            PRINTF("TX TYPE: %u\n", context->txType);
         }
         if (!context->processingField) {
             PRINTF("PROCESSING FIELD\n");
diff --git a/src_common/ethUstream.h b/src_common/ethUstream.h
index 24cbaa0..cd30835 100644
--- a/src_common/ethUstream.h
+++ b/src_common/ethUstream.h
@@ -55,8 +55,10 @@ typedef enum rlpTxField_e {
 
 // EIP 2718 TransactionType
 typedef enum txType_e {
-    LegacyTransaction = 1,
-    BerlinTransaction = 2
+    MIN_TX_TYPE,
+    LEGACY_TX,
+    BERLIN_TX,
+    MAX_TX_TYPE,
 } txType_e;
 
 typedef enum parserStatus_e {

From 9c20c54013ffe34477cfa6d31c171b2b1b200aba Mon Sep 17 00:00:00 2001
From: pscott <scott.piriou@ledger.fr>
Date: Thu, 15 Apr 2021 15:37:26 +0200
Subject: [PATCH 03/23] Apply clang format

---
 src_common/ethUstream.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src_common/ethUstream.c b/src_common/ethUstream.c
index 18cd896..fd6cc2e 100644
--- a/src_common/ethUstream.c
+++ b/src_common/ethUstream.c
@@ -266,7 +266,7 @@ static parserStatus_e processTxInternal(txContext_t *context) {
         // EIP 2718: TransactionType might be present before the TransactionPayload.
         if (*context->workBuffer > 0x00 && *context->workBuffer < 0x7f) {
             PRINTF("TX TYPE: %u\n", context->txType);
-            if (*context->workBuffer < MIN_TX_TYPE || *context->workBuffer > MAX_TX_TYPE ) {
+            if (*context->workBuffer < MIN_TX_TYPE || *context->workBuffer > MAX_TX_TYPE) {
                 PRINTF("Transaction type not supported\n");
                 return USTREAM_FAULT;
             }

From 65ac116e911722160b3e1632cde52b1318fd0420 Mon Sep 17 00:00:00 2001
From: pscott <scott.piriou@ledger.fr>
Date: Thu, 15 Apr 2021 15:38:38 +0200
Subject: [PATCH 04/23] Restrict txType to be within enum bounds

---
 src_common/ethUstream.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src_common/ethUstream.c b/src_common/ethUstream.c
index fd6cc2e..20d96d8 100644
--- a/src_common/ethUstream.c
+++ b/src_common/ethUstream.c
@@ -266,7 +266,7 @@ static parserStatus_e processTxInternal(txContext_t *context) {
         // EIP 2718: TransactionType might be present before the TransactionPayload.
         if (*context->workBuffer > 0x00 && *context->workBuffer < 0x7f) {
             PRINTF("TX TYPE: %u\n", context->txType);
-            if (*context->workBuffer < MIN_TX_TYPE || *context->workBuffer > MAX_TX_TYPE) {
+            if (*context->workBuffer <= MIN_TX_TYPE || *context->workBuffer >= MAX_TX_TYPE) {
                 PRINTF("Transaction type not supported\n");
                 return USTREAM_FAULT;
             }

From 9e6610c56a2c7bc18c01668f6c9f84c7e569e362 Mon Sep 17 00:00:00 2001
From: pscott <scott.piriou@ledger.fr>
Date: Thu, 15 Apr 2021 15:42:46 +0200
Subject: [PATCH 05/23] Fix debug messages

---
 src_common/ethUstream.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/src_common/ethUstream.c b/src_common/ethUstream.c
index 20d96d8..023dc45 100644
--- a/src_common/ethUstream.c
+++ b/src_common/ethUstream.c
@@ -265,7 +265,7 @@ static parserStatus_e processTxInternal(txContext_t *context) {
         }
         // EIP 2718: TransactionType might be present before the TransactionPayload.
         if (*context->workBuffer > 0x00 && *context->workBuffer < 0x7f) {
-            PRINTF("TX TYPE: %u\n", context->txType);
+            PRINTF("TX TYPE: %u\n", *context->workBuffer);
             if (*context->workBuffer <= MIN_TX_TYPE || *context->workBuffer >= MAX_TX_TYPE) {
                 PRINTF("Transaction type not supported\n");
                 return USTREAM_FAULT;
@@ -274,7 +274,6 @@ static parserStatus_e processTxInternal(txContext_t *context) {
             context->workBuffer++;
         }
         if (!context->processingField) {
-            PRINTF("PROCESSING FIELD\n");
             bool canDecode = false;
             uint32_t offset;
             while (context->commandLength != 0) {

From 9876999b8d49174c08e086093c6e8a3800f45766 Mon Sep 17 00:00:00 2001
From: pscott <scott.piriou@ledger.fr>
Date: Thu, 15 Apr 2021 16:13:42 +0200
Subject: [PATCH 06/23] Enumerate through variants

---
 src_common/ethUstream.c | 12 ++++++++----
 src_common/ethUstream.h |  3 ---
 2 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/src_common/ethUstream.c b/src_common/ethUstream.c
index 023dc45..517691e 100644
--- a/src_common/ethUstream.c
+++ b/src_common/ethUstream.c
@@ -265,13 +265,17 @@ static parserStatus_e processTxInternal(txContext_t *context) {
         }
         // EIP 2718: TransactionType might be present before the TransactionPayload.
         if (*context->workBuffer > 0x00 && *context->workBuffer < 0x7f) {
-            PRINTF("TX TYPE: %u\n", *context->workBuffer);
-            if (*context->workBuffer <= MIN_TX_TYPE || *context->workBuffer >= MAX_TX_TYPE) {
+            uint8_t maybeType = *context->workBuffer;
+            PRINTF("TX TYPE: %u\n", maybeType);
+
+            // Enumerate through all supported txTypes here...
+            if (maybeType == LEGACY_TX) {
+                context->txType = *context->workBuffer;
+                context->workBuffer++;
+            } else {
                 PRINTF("Transaction type not supported\n");
                 return USTREAM_FAULT;
             }
-            context->txType = *context->workBuffer;
-            context->workBuffer++;
         }
         if (!context->processingField) {
             bool canDecode = false;
diff --git a/src_common/ethUstream.h b/src_common/ethUstream.h
index cd30835..1b9bf2e 100644
--- a/src_common/ethUstream.h
+++ b/src_common/ethUstream.h
@@ -55,10 +55,7 @@ typedef enum rlpTxField_e {
 
 // EIP 2718 TransactionType
 typedef enum txType_e {
-    MIN_TX_TYPE,
     LEGACY_TX,
-    BERLIN_TX,
-    MAX_TX_TYPE,
 } txType_e;
 
 typedef enum parserStatus_e {

From 99950a396c37be4f314cc7dfcf3293b4f8a01066 Mon Sep 17 00:00:00 2001
From: pscott <scott.piriou@ledger.fr>
Date: Thu, 15 Apr 2021 16:19:12 +0200
Subject: [PATCH 07/23] Add max and min values and restrict bounds

---
 src_common/ethUstream.c | 2 +-
 src_common/ethUstream.h | 3 +++
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/src_common/ethUstream.c b/src_common/ethUstream.c
index 517691e..5d404fe 100644
--- a/src_common/ethUstream.c
+++ b/src_common/ethUstream.c
@@ -264,7 +264,7 @@ static parserStatus_e processTxInternal(txContext_t *context) {
             return USTREAM_PROCESSING;
         }
         // EIP 2718: TransactionType might be present before the TransactionPayload.
-        if (*context->workBuffer > 0x00 && *context->workBuffer < 0x7f) {
+        if (*context->workBuffer >= MIN_TX_TYPE && *context->workBuffer <= MAX_TX_TYPE) {
             uint8_t maybeType = *context->workBuffer;
             PRINTF("TX TYPE: %u\n", maybeType);
 
diff --git a/src_common/ethUstream.h b/src_common/ethUstream.h
index 1b9bf2e..05921bb 100644
--- a/src_common/ethUstream.h
+++ b/src_common/ethUstream.h
@@ -53,6 +53,9 @@ typedef enum rlpTxField_e {
     TX_RLP_DONE
 } rlpTxField_e;
 
+#define MIN_TX_TYPE 0x00
+#define MAX_TX_TYPE 0x7f
+
 // EIP 2718 TransactionType
 typedef enum txType_e {
     LEGACY_TX,

From 01fd39ea96ced88c7122313574fbe234527b7119 Mon Sep 17 00:00:00 2001
From: pscott <scott.piriou@ledger.fr>
Date: Thu, 15 Apr 2021 16:20:39 +0200
Subject: [PATCH 08/23] Add LEGACY_TX

---
 src_common/ethUstream.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src_common/ethUstream.h b/src_common/ethUstream.h
index 05921bb..34bd413 100644
--- a/src_common/ethUstream.h
+++ b/src_common/ethUstream.h
@@ -58,7 +58,7 @@ typedef enum rlpTxField_e {
 
 // EIP 2718 TransactionType
 typedef enum txType_e {
-    LEGACY_TX,
+    LEGACY_TX = 1,
 } txType_e;
 
 typedef enum parserStatus_e {

From 6ccc36fa39f81e95a4c2d7f76934f559de366002 Mon Sep 17 00:00:00 2001
From: pscott <scott.piriou@ledger.fr>
Date: Thu, 15 Apr 2021 17:08:09 +0200
Subject: [PATCH 09/23] Move txType parsing outside of forloop

---
 src_common/ethUstream.c | 29 ++++++++++++++++-------------
 1 file changed, 16 insertions(+), 13 deletions(-)

diff --git a/src_common/ethUstream.c b/src_common/ethUstream.c
index 5d404fe..2bd36a6 100644
--- a/src_common/ethUstream.c
+++ b/src_common/ethUstream.c
@@ -249,6 +249,22 @@ static void processV(txContext_t *context) {
 }
 
 static parserStatus_e processTxInternal(txContext_t *context) {
+    // EIP 2718: TransactionType might be present before the TransactionPayload.
+    uint8_t txType = *context->workBuffer;
+    if (txType >= MIN_TX_TYPE && txType <= MAX_TX_TYPE) {
+        PRINTF("TX TYPE: %u\n", txType);
+
+        // Enumerate through all supported txTypes here...
+        if (txType == LEGACY_TX) {
+            context->txType = txType;
+            context->workBuffer++;
+        } else {
+            PRINTF("Transaction type not supported\n");
+            return USTREAM_FAULT;
+        }
+    }
+
+    // Parse the TransactionPayload.
     for (;;) {
         customStatus_e customStatus = CUSTOM_NOT_HANDLED;
         // EIP 155 style transasction
@@ -263,20 +279,7 @@ static parserStatus_e processTxInternal(txContext_t *context) {
         if (context->commandLength == 0) {
             return USTREAM_PROCESSING;
         }
-        // EIP 2718: TransactionType might be present before the TransactionPayload.
-        if (*context->workBuffer >= MIN_TX_TYPE && *context->workBuffer <= MAX_TX_TYPE) {
-            uint8_t maybeType = *context->workBuffer;
-            PRINTF("TX TYPE: %u\n", maybeType);
 
-            // Enumerate through all supported txTypes here...
-            if (maybeType == LEGACY_TX) {
-                context->txType = *context->workBuffer;
-                context->workBuffer++;
-            } else {
-                PRINTF("Transaction type not supported\n");
-                return USTREAM_FAULT;
-            }
-        }
         if (!context->processingField) {
             bool canDecode = false;
             uint32_t offset;

From 5dd99c3d48b252e719dcbdf7126d0721cd52070a Mon Sep 17 00:00:00 2001
From: pscott <scott.piriou@ledger.fr>
Date: Thu, 15 Apr 2021 17:59:41 +0200
Subject: [PATCH 10/23] Move TxType parsing in cmd_signTx and add 0x6501 error

---
 doc/ethapp.asc                   |  1 +
 src_common/ethUstream.c          | 18 +-----------------
 src_features/signTx/cmd_signTx.c | 16 ++++++++++++++++
 3 files changed, 18 insertions(+), 17 deletions(-)

diff --git a/doc/ethapp.asc b/doc/ethapp.asc
index d57e13c..35ef221 100644
--- a/doc/ethapp.asc
+++ b/doc/ethapp.asc
@@ -473,6 +473,7 @@ The following standard Status Words are returned for all APDUs - some specific S
 [width="80%"]
 |===============================================================================================
 | *SW*     | *Description*
+|   6501   | TransactionType not supported
 |   6700   | Incorrect length
 |   6982   | Security status not satisfied (Canceled by user)
 |   6A80   | Invalid data
diff --git a/src_common/ethUstream.c b/src_common/ethUstream.c
index 2bd36a6..6cf92d9 100644
--- a/src_common/ethUstream.c
+++ b/src_common/ethUstream.c
@@ -249,25 +249,9 @@ static void processV(txContext_t *context) {
 }
 
 static parserStatus_e processTxInternal(txContext_t *context) {
-    // EIP 2718: TransactionType might be present before the TransactionPayload.
-    uint8_t txType = *context->workBuffer;
-    if (txType >= MIN_TX_TYPE && txType <= MAX_TX_TYPE) {
-        PRINTF("TX TYPE: %u\n", txType);
-
-        // Enumerate through all supported txTypes here...
-        if (txType == LEGACY_TX) {
-            context->txType = txType;
-            context->workBuffer++;
-        } else {
-            PRINTF("Transaction type not supported\n");
-            return USTREAM_FAULT;
-        }
-    }
-
-    // Parse the TransactionPayload.
     for (;;) {
         customStatus_e customStatus = CUSTOM_NOT_HANDLED;
-        // EIP 155 style transasction
+        // EIP 155 style transaction
         if (context->currentField == TX_RLP_DONE) {
             return USTREAM_FINISHED;
         }
diff --git a/src_features/signTx/cmd_signTx.c b/src_features/signTx/cmd_signTx.c
index e721d06..d08c528 100644
--- a/src_features/signTx/cmd_signTx.c
+++ b/src_features/signTx/cmd_signTx.c
@@ -40,6 +40,22 @@ void handleSign(uint8_t p1,
         }
         dataPresent = false;
         dataContext.tokenContext.pluginAvailable = 0;
+
+        // EIP 2718: TransactionType might be present before the TransactionPayload.
+        uint8_t txType = *workBuffer;
+        if (txType >= MIN_TX_TYPE && txType <= MAX_TX_TYPE) {
+            PRINTF("Transaction type: %u\n", txType);
+
+            // Enumerate through all supported txTypes here...
+            if (txType == LEGACY_TX) {
+                txContext.txType = txType;
+                workBuffer++;
+                dataLength--;
+            } else {
+                PRINTF("Transaction type not supported\n");
+                THROW(0x6501);
+            }
+        }
         initTx(&txContext, &global_sha3, &tmpContent.txContent, customProcessor, NULL);
     } else if (p1 != P1_MORE) {
         THROW(0x6B00);

From 970f0355dd4adc976e7342d16f33e6ed9fc0b795 Mon Sep 17 00:00:00 2001
From: pscott <scott.piriou@ledger.fr>
Date: Wed, 21 Apr 2021 16:56:17 +0200
Subject: [PATCH 11/23] Add support for EIP2718 (enveloppe) and EIP2930 (acess
 list tx); Display chain ID when different from 1 (ethereum mainnet)

---
 Makefile                               |   7 +
 doc/ethapp.asc                         |   1 +
 src/chainConfig.h                      |   2 +
 src/eth_plugin_handler.c               |   1 +
 src/main.c                             |   4 +
 src/shared_context.h                   |   4 +-
 src/utils.c                            |  66 ++++--
 src/utils.h                            |   6 +-
 src_common/ethUstream.c                | 292 ++++++++++++++++++-------
 src_common/ethUstream.h                |  71 ++++--
 src_features/signTx/cmd_signTx.c       |   8 +-
 src_features/signTx/logic_signTx.c     |  45 +++-
 src_features/signTx/ui_common_signTx.c |   2 +-
 src_features/signTx/ui_flow_signTx.c   |  56 +++--
 14 files changed, 419 insertions(+), 146 deletions(-)

diff --git a/Makefile b/Makefile
index df9c25a..203dcb9 100755
--- a/Makefile
+++ b/Makefile
@@ -251,6 +251,13 @@ else
 DEFINES   += IO_SEPROXYHAL_BUFFER_SIZE_B=72
 endif
 
+# Enables direct data signing without having to specify it in the settings. Useful when testing with speculos.
+ALLOW_DATA:=0
+ifneq ($(ALLOW_DATA),0)
+DEFINES += HAVE_ALLOW_DATA
+endif
+
+
 # Enabling debug PRINTF
 DEBUG:=0
 ifneq ($(DEBUG),0)
diff --git a/doc/ethapp.asc b/doc/ethapp.asc
index 35ef221..ac716dd 100644
--- a/doc/ethapp.asc
+++ b/doc/ethapp.asc
@@ -474,6 +474,7 @@ The following standard Status Words are returned for all APDUs - some specific S
 |===============================================================================================
 | *SW*     | *Description*
 |   6501   | TransactionType not supported
+|   6502   | Not enough space for conversion from uint32_t to string
 |   6700   | Incorrect length
 |   6982   | Security status not satisfied (Canceled by user)
 |   6A80   | Invalid data
diff --git a/src/chainConfig.h b/src/chainConfig.h
index db38a3e..2172b0b 100644
--- a/src/chainConfig.h
+++ b/src/chainConfig.h
@@ -61,4 +61,6 @@ typedef struct chain_config_s {
     chain_kind_t kind;
 } chain_config_t;
 
+#define ETHEREUM_MAINNET_CHAINID 1
+
 #endif /* _CHAIN_CONFIG_H_ */
diff --git a/src/eth_plugin_handler.c b/src/eth_plugin_handler.c
index ccaa86e..d9f3d5d 100644
--- a/src/eth_plugin_handler.c
+++ b/src/eth_plugin_handler.c
@@ -59,6 +59,7 @@ void eth_plugin_prepare_query_contract_UI(ethQueryContractUI_t *queryContractUI,
 int eth_plugin_perform_init(uint8_t *contractAddress, ethPluginInitContract_t *init) {
     uint8_t i;
     const uint8_t **selectors;
+    return 0;
     dataContext.tokenContext.pluginAvailable = 0;
     // Handle hardcoded plugin list
     PRINTF("Selector %.*H\n", 4, init->selector);
diff --git a/src/main.c b/src/main.c
index c6e5898..c7f699e 100644
--- a/src/main.c
+++ b/src/main.c
@@ -714,7 +714,11 @@ void coin_main(chain_config_t *coin_config) {
 
                 if (N_storage.initialized != 0x01) {
                     internalStorage_t storage;
+#ifdef HAVE_ALLOW_DATA
+                    storage.dataAllowed = 0x01;
+#else
                     storage.dataAllowed = 0x00;
+#endif
                     storage.contractDetails = 0x00;
                     storage.displayNonce = 0x00;
                     storage.initialized = 0x01;
diff --git a/src/shared_context.h b/src/shared_context.h
index 63db781..7da81b4 100644
--- a/src/shared_context.h
+++ b/src/shared_context.h
@@ -158,7 +158,9 @@ typedef struct txStringProperties_t {
     char fullAddress[43];
     char fullAmount[50];
     char maxFee[50];
-    char nonce[8];  // 10M tx per account ought to be enough for everybody
+    char nonce[8];    // 10M tx per account ought to be enough for everybody
+    char chainID[8];  // 10M different chainID ought to be enough for people to find a unique
+                      // chainID for their token / chain.
 } txStringProperties_t;
 
 typedef struct strDataTmp_t {
diff --git a/src/utils.c b/src/utils.c
index 43ccc61..0b7d583 100644
--- a/src/utils.c
+++ b/src/utils.c
@@ -53,22 +53,58 @@ int local_strchr(char *string, char ch) {
     return -1;
 }
 
-uint32_t getV(txContent_t *txContent) {
-    uint32_t v = 0;
-    if (txContent->vLength == 1) {
-        v = txContent->v[0];
-    } else if (txContent->vLength == 2) {
-        v = (txContent->v[0] << 8) | txContent->v[1];
-    } else if (txContent->vLength == 3) {
-        v = (txContent->v[0] << 16) | (txContent->v[1] << 8) | txContent->v[2];
-    } else if (txContent->vLength == 4) {
-        v = (txContent->v[0] << 24) | (txContent->v[1] << 16) | (txContent->v[2] << 8) |
-            txContent->v[3];
-    } else if (txContent->vLength != 0) {
-        PRINTF("Unexpected v format\n");
-        THROW(EXCEPTION);
+// Almost like U4BE except that it takes `size` as a parameter.
+uint32_t u32_from_BE(uint8_t *in, uint8_t size) {
+    uint32_t res = 0;
+    if (size == 1) {
+        res = in[0];
+    } else if (size == 2) {
+        res = (in[0] << 8) | in[1];
+    } else if (size == 3) {
+        res = (in[0] << 16) | (in[1] << 8) | in[2];
+    } else {
+        res = (in[0] << 24) | (in[1] << 16) | (in[2] << 8) | in[3];
+    }
+    return res;
+}
+
+// Converts a uint32_t to a string.
+void u32_to_str(char *dest, uint32_t in, uint8_t dest_size) {
+    uint8_t i = 0;
+
+    // Get the first digit (in case it's 0).
+    dest[i] = in % 10 + '0';
+    in /= 10;
+    i++;
+
+    // Get every digit.
+    while (in != 0) {
+        if (i >= dest_size) {
+            THROW(6502);
+        }
+        dest[i] = in % 10 + '0';
+        in /= 10;
+        i++;
+    }
+
+    // Null terminate the string.
+    dest[i] = '\0';
+    i--;
+
+    // Reverse the string
+    uint8_t end = i;
+    char tmp;
+    i = 0;
+    while (i < end) {
+        // Swap the first and last elements.
+        tmp = dest[i];
+        dest[i] = dest[end];
+        dest[end] = tmp;
+
+        // Decrease the interval size.
+        i++;
+        end--;
     }
-    return v;
 }
 
 void amountToString(uint8_t *amount,
diff --git a/src/utils.h b/src/utils.h
index 46dfa5d..582fb62 100644
--- a/src/utils.h
+++ b/src/utils.h
@@ -28,7 +28,11 @@ void convertUint256BE(uint8_t* data, uint32_t length, uint256_t* target);
 
 int local_strchr(char* string, char ch);
 
-uint32_t getV(txContent_t* txContent);
+// `itoa` for uint32_t.
+void u32_to_str(char* dest, uint8_t dest_size, uint32_t in);
+
+// Converts a list of bytes (in BE) of length `size` to a uint32_t.
+uint32_t u32_from_BE(uint8_t* in, uint8_t size);
 
 void amountToString(uint8_t* amount,
                     uint8_t amount_len,
diff --git a/src_common/ethUstream.c b/src_common/ethUstream.c
index 6cf92d9..22afedc 100644
--- a/src_common/ethUstream.c
+++ b/src_common/ethUstream.c
@@ -20,6 +20,7 @@
 
 #include "ethUstream.h"
 #include "ethUtils.h"
+#include "utils.h"
 
 #define MAX_INT256  32
 #define MAX_ADDRESS 20
@@ -30,12 +31,15 @@ void initTx(txContext_t *context,
             txContent_t *content,
             ustreamProcess_t customProcessor,
             void *extra) {
+    uint8_t save = context->txType;
+
     memset(context, 0, sizeof(txContext_t));
+    context->txType = save;
     context->sha3 = sha3;
     context->content = content;
     context->customProcessor = customProcessor;
     context->extra = extra;
-    context->currentField = TX_RLP_CONTENT;
+    context->currentField = RLP_NONE + 1;
     cx_keccak_init(context->sha3, 256);
 }
 
@@ -86,6 +90,22 @@ static void processContent(txContext_t *context) {
     context->processingField = false;
 }
 
+static void processAccessList(txContext_t *context) {
+    if (!context->currentFieldIsList) {
+        PRINTF("Invalid type for RLP_DATA\n");
+        THROW(EXCEPTION);
+    }
+    if (context->currentFieldPos < context->currentFieldLength) {
+        uint32_t copySize =
+            MIN(context->commandLength, context->currentFieldLength - context->currentFieldPos);
+        copyTxData(context, NULL, copySize);
+    }
+    if (context->currentFieldPos == context->currentFieldLength) {
+        context->currentField++;
+        context->processingField = false;
+    }
+}
+
 static void processType(txContext_t *context) {
     if (context->currentFieldIsList) {
         PRINTF("Invalid type for RLP_TYPE\n");
@@ -106,6 +126,28 @@ static void processType(txContext_t *context) {
     }
 }
 
+static void processChainID(txContext_t *context) {
+    if (context->currentFieldIsList) {
+        PRINTF("Invalid type for RLP_CHAINID\n");
+        THROW(EXCEPTION);
+    }
+    if (context->currentFieldLength > MAX_INT256) {
+        PRINTF("Invalid length for RLP_CHAINID\n");
+        THROW(EXCEPTION);
+    }
+    if (context->currentFieldPos < context->currentFieldLength) {
+        uint32_t copySize =
+            MIN(context->commandLength, context->currentFieldLength - context->currentFieldPos);
+        copyTxData(context, context->content->chainID.value, copySize);
+    }
+    if (context->currentFieldPos == context->currentFieldLength) {
+        context->content->chainID.length = context->currentFieldLength;
+        context->currentField++;
+        context->processingField = false;
+    }
+    PRINTF("chainID: %.*H\n", context->content->chainID.length, context->content->chainID.value);
+}
+
 static void processNonce(txContext_t *context) {
     if (context->currentFieldIsList) {
         PRINTF("Invalid type for RLP_NONCE\n");
@@ -148,6 +190,11 @@ static void processStartGas(txContext_t *context) {
     }
 }
 
+// Alias over `processStartGas()`.
+static void processGasLimit(txContext_t *context) {
+    processStartGas(context);
+}
+
 static void processGasprice(txContext_t *context) {
     if (context->currentFieldIsList) {
         PRINTF("Invalid type for RLP_GASPRICE\n");
@@ -248,68 +295,167 @@ static void processV(txContext_t *context) {
     }
 }
 
+static bool processEIP2930Tx(txContext_t *context) {
+    switch (context->currentField) {
+        case EIP2930_RLP_CONTENT:
+            processContent(context);
+            if ((context->processingFlags & TX_FLAG_TYPE) == 0) {
+                context->currentField++;
+            }
+            break;
+        case EIP2930_RLP_TYPE:
+            processType(context);
+            break;
+        case EIP2930_RLP_CHAINID:
+            processChainID(context);
+            break;
+        case EIP2930_RLP_NONCE:
+            processNonce(context);
+            break;
+        case EIP2930_RLP_GASPRICE:
+            processGasprice(context);
+            break;
+        case EIP2930_RLP_GASLIMIT:
+            processGasLimit(context);
+            break;
+        case EIP2930_RLP_TO:
+            processTo(context);
+            break;
+        case EIP2930_RLP_VALUE:
+            processValue(context);
+            break;
+        case EIP2930_RLP_YPARITY:
+            processV(context);
+            break;
+        case EIP2930_RLP_ACCESS_LIST:
+            processAccessList(context);
+            break;
+        case EIP2930_RLP_DATA:
+        case EIP2930_RLP_SENDER_R:
+        case EIP2930_RLP_SENDER_S:
+            processData(context);
+            break;
+        default:
+            PRINTF("Invalid RLP decoder context\n");
+            return true;
+    }
+    return false;
+}
+
+static bool processLegacyTx(txContext_t *context) {
+    PRINTF("Processing legacy\n");
+    switch (context->currentField) {
+        case LEGACY_RLP_CONTENT:
+            processContent(context);
+            if ((context->processingFlags & TX_FLAG_TYPE) == 0) {
+                context->currentField++;
+            }
+            break;
+        case LEGACY_RLP_TYPE:
+            processType(context);
+            break;
+        case LEGACY_RLP_NONCE:
+            processNonce(context);
+            break;
+        case LEGACY_RLP_GASPRICE:
+            processGasprice(context);
+            break;
+        case LEGACY_RLP_STARTGAS:
+            processStartGas(context);
+            break;
+        case LEGACY_RLP_TO:
+            processTo(context);
+            break;
+        case LEGACY_RLP_VALUE:
+            processValue(context);
+            break;
+        case LEGACY_RLP_DATA:
+        case LEGACY_RLP_R:
+        case LEGACY_RLP_S:
+            processData(context);
+            break;
+        case LEGACY_RLP_V:
+            processV(context);
+            break;
+        default:
+            PRINTF("Invalid RLP decoder context\n");
+            return true;
+    }
+    return false;
+}
+
+static parserStatus_e parseRLP(txContext_t *context) {
+    bool canDecode = false;
+    uint32_t offset;
+    while (context->commandLength != 0) {
+        bool valid;
+        // Feed the RLP buffer until the length can be decoded
+        context->rlpBuffer[context->rlpBufferPos++] = readTxByte(context);
+        if (rlpCanDecode(context->rlpBuffer, context->rlpBufferPos, &valid)) {
+            // Can decode now, if valid
+            if (!valid) {
+                PRINTF("RLP pre-decode error\n");
+                return USTREAM_FAULT;
+            }
+            canDecode = true;
+            break;
+        }
+        // Cannot decode yet
+        // Sanity check
+        if (context->rlpBufferPos == sizeof(context->rlpBuffer)) {
+            PRINTF("RLP pre-decode logic error\n");
+            return USTREAM_FAULT;
+        }
+    }
+    if (!canDecode) {
+        PRINTF("Can't decode\n");
+        return USTREAM_PROCESSING;
+    }
+    // Ready to process this field
+    if (!rlpDecodeLength(context->rlpBuffer,
+                         context->rlpBufferPos,
+                         &context->currentFieldLength,
+                         &offset,
+                         &context->currentFieldIsList)) {
+        PRINTF("RLP decode error\n");
+        return USTREAM_FAULT;
+    }
+    if (offset == 0) {
+        // Hack for single byte, self encoded
+        context->workBuffer--;
+        context->commandLength++;
+        context->fieldSingleByte = true;
+    } else {
+        context->fieldSingleByte = false;
+    }
+    context->currentFieldPos = 0;
+    context->rlpBufferPos = 0;
+    context->processingField = true;
+    return USTREAM_CONTINUE;
+}
+
 static parserStatus_e processTxInternal(txContext_t *context) {
     for (;;) {
         customStatus_e customStatus = CUSTOM_NOT_HANDLED;
         // EIP 155 style transaction
-        if (context->currentField == TX_RLP_DONE) {
+        if (IS_PARSING_DONE(context)) {
             return USTREAM_FINISHED;
         }
         // Old style transaction
-        if ((context->currentField == TX_RLP_V) && (context->commandLength == 0)) {
+        if ((context->currentField == LEGACY_RLP_V ||
+             context->currentField == EIP2930_RLP_YPARITY) &&
+            (context->commandLength == 0)) {
             context->content->vLength = 0;
             return USTREAM_FINISHED;
         }
         if (context->commandLength == 0) {
             return USTREAM_PROCESSING;
         }
-
         if (!context->processingField) {
-            bool canDecode = false;
-            uint32_t offset;
-            while (context->commandLength != 0) {
-                bool valid;
-                // Feed the RLP buffer until the length can be decoded
-                context->rlpBuffer[context->rlpBufferPos++] = readTxByte(context);
-                if (rlpCanDecode(context->rlpBuffer, context->rlpBufferPos, &valid)) {
-                    // Can decode now, if valid
-                    if (!valid) {
-                        PRINTF("RLP pre-decode error\n");
-                        return USTREAM_FAULT;
-                    }
-                    canDecode = true;
-                    break;
-                }
-                // Cannot decode yet
-                // Sanity check
-                if (context->rlpBufferPos == sizeof(context->rlpBuffer)) {
-                    PRINTF("RLP pre-decode logic error\n");
-                    return USTREAM_FAULT;
-                }
+            parserStatus_e status = parseRLP(context);
+            if (status != USTREAM_CONTINUE) {
+                return status;
             }
-            if (!canDecode) {
-                return USTREAM_PROCESSING;
-            }
-            // Ready to process this field
-            if (!rlpDecodeLength(context->rlpBuffer,
-                                 context->rlpBufferPos,
-                                 &context->currentFieldLength,
-                                 &offset,
-                                 &context->currentFieldIsList)) {
-                PRINTF("RLP decode error\n");
-                return USTREAM_FAULT;
-            }
-            if (offset == 0) {
-                // Hack for single byte, self encoded
-                context->workBuffer--;
-                context->commandLength++;
-                context->fieldSingleByte = true;
-            } else {
-                context->fieldSingleByte = false;
-            }
-            context->currentFieldPos = 0;
-            context->rlpBufferPos = 0;
-            context->processingField = true;
         }
         if (context->customProcessor != NULL) {
             customStatus = context->customProcessor(context);
@@ -328,41 +474,25 @@ static parserStatus_e processTxInternal(txContext_t *context) {
             }
         }
         if (customStatus == CUSTOM_NOT_HANDLED) {
-            switch (context->currentField) {
-                case TX_RLP_CONTENT:
-                    processContent(context);
-                    if ((context->processingFlags & TX_FLAG_TYPE) == 0) {
-                        context->currentField++;
+            PRINTF("Current field: %u\n", context->currentField);
+            switch (context->txType) {
+                bool fault;
+                case LEGACY:
+                    fault = processLegacyTx(context);
+                    if (fault) {
+                        return USTREAM_FAULT;
+                    } else {
+                        break;
+                    }
+                case EIP2930:
+                    fault = processEIP2930Tx(context);
+                    if (fault) {
+                        return USTREAM_FAULT;
+                    } else {
+                        break;
                     }
-                    break;
-                case TX_RLP_TYPE:
-                    processType(context);
-                    break;
-                case TX_RLP_NONCE:
-                    processNonce(context);
-                    break;
-                case TX_RLP_GASPRICE:
-                    processGasprice(context);
-                    break;
-                case TX_RLP_STARTGAS:
-                    processStartGas(context);
-                    break;
-                case TX_RLP_VALUE:
-                    processValue(context);
-                    break;
-                case TX_RLP_TO:
-                    processTo(context);
-                    break;
-                case TX_RLP_DATA:
-                case TX_RLP_R:
-                case TX_RLP_S:
-                    processData(context);
-                    break;
-                case TX_RLP_V:
-                    processV(context);
-                    break;
                 default:
-                    PRINTF("Invalid RLP decoder context\n");
+                    PRINTF("Transaction type %u is not supported\n", context->txType);
                     return USTREAM_FAULT;
             }
         }
diff --git a/src_common/ethUstream.h b/src_common/ethUstream.h
index 34bd413..531750b 100644
--- a/src_common/ethUstream.h
+++ b/src_common/ethUstream.h
@@ -37,35 +37,63 @@ typedef customStatus_e (*ustreamProcess_t)(struct txContext_t *context);
 
 #define TX_FLAG_TYPE 0x01
 
-typedef enum rlpTxField_e {
-    TX_RLP_NONE = 0,
-    TX_RLP_CONTENT,
-    TX_RLP_TYPE,
-    TX_RLP_NONCE,
-    TX_RLP_GASPRICE,
-    TX_RLP_STARTGAS,
-    TX_RLP_TO,
-    TX_RLP_VALUE,
-    TX_RLP_DATA,
-    TX_RLP_V,
-    TX_RLP_R,
-    TX_RLP_S,
-    TX_RLP_DONE
-} rlpTxField_e;
+// First variant of every Tx enum.
+#define RLP_NONE 0
+
+#define IS_PARSING_DONE(ctx)                                            \
+    ((ctx->txType == LEGACY && ctx->currentField == LEGACY_RLP_DONE) || \
+     (ctx->txType == EIP2930 && ctx->currentField == EIP2930_RLP_DONE))
+
+typedef enum rlpLegacyTxField_e {
+    LEGACY_RLP_NONE = RLP_NONE,
+    LEGACY_RLP_CONTENT,
+    LEGACY_RLP_TYPE,
+    LEGACY_RLP_NONCE,
+    LEGACY_RLP_GASPRICE,
+    LEGACY_RLP_STARTGAS,
+    LEGACY_RLP_TO,
+    LEGACY_RLP_VALUE,
+    LEGACY_RLP_DATA,
+    LEGACY_RLP_V,
+    LEGACY_RLP_R,
+    LEGACY_RLP_S,
+    LEGACY_RLP_DONE
+} rlpLegacyTxField_e;
+
+typedef enum rlpEIP2930TxField_e {
+    EIP2930_RLP_NONE = RLP_NONE,
+    EIP2930_RLP_CONTENT,
+    EIP2930_RLP_TYPE,
+    EIP2930_RLP_CHAINID,
+    EIP2930_RLP_NONCE,
+    EIP2930_RLP_GASPRICE,
+    EIP2930_RLP_GASLIMIT,
+    EIP2930_RLP_TO,
+    EIP2930_RLP_VALUE,
+    EIP2930_RLP_DATA,
+    EIP2930_RLP_ACCESS_LIST,
+    EIP2930_RLP_YPARITY,
+    EIP2930_RLP_SENDER_R,
+    EIP2930_RLP_SENDER_S,
+    EIP2930_RLP_DONE
+} rlpEIP2930TxField_e;
 
 #define MIN_TX_TYPE 0x00
 #define MAX_TX_TYPE 0x7f
 
 // EIP 2718 TransactionType
+// Valid transaction types should be in [0x00, 0x7f]
 typedef enum txType_e {
-    LEGACY_TX = 1,
+    EIP2930 = 0x01,
+    LEGACY = 0xc0  // Legacy tx are greater than or equal to 0xc0.
 } txType_e;
 
 typedef enum parserStatus_e {
-    USTREAM_PROCESSING,
-    USTREAM_SUSPENDED,
-    USTREAM_FINISHED,
-    USTREAM_FAULT
+    USTREAM_PROCESSING,  // Parsing is in progress
+    USTREAM_SUSPENDED,   // Parsing has been suspended
+    USTREAM_FINISHED,    // Parsing is done
+    USTREAM_FAULT,       // An error was encountered while parsing
+    USTREAM_CONTINUE     // Used internally to signify we can keep on parsing
 } parserStatus_e;
 
 typedef struct txInt256_t {
@@ -78,6 +106,7 @@ typedef struct txContent_t {
     txInt256_t startgas;
     txInt256_t value;
     txInt256_t nonce;
+    txInt256_t chainID;
     uint8_t destination[20];
     uint8_t destinationLength;
     uint8_t v[4];
@@ -85,7 +114,7 @@ typedef struct txContent_t {
 } txContent_t;
 
 typedef struct txContext_t {
-    rlpTxField_e currentField;
+    uint8_t currentField;
     cx_sha3_t *sha3;
     uint32_t currentFieldLength;
     uint32_t currentFieldPos;
diff --git a/src_features/signTx/cmd_signTx.c b/src_features/signTx/cmd_signTx.c
index d08c528..eabbbcf 100644
--- a/src_features/signTx/cmd_signTx.c
+++ b/src_features/signTx/cmd_signTx.c
@@ -44,10 +44,8 @@ void handleSign(uint8_t p1,
         // EIP 2718: TransactionType might be present before the TransactionPayload.
         uint8_t txType = *workBuffer;
         if (txType >= MIN_TX_TYPE && txType <= MAX_TX_TYPE) {
-            PRINTF("Transaction type: %u\n", txType);
-
             // Enumerate through all supported txTypes here...
-            if (txType == LEGACY_TX) {
+            if (txType == EIP2930) {
                 txContext.txType = txType;
                 workBuffer++;
                 dataLength--;
@@ -55,6 +53,8 @@ void handleSign(uint8_t p1,
                 PRINTF("Transaction type not supported\n");
                 THROW(0x6501);
             }
+        } else {
+            txContext.txType = LEGACY;
         }
         initTx(&txContext, &global_sha3, &tmpContent.txContent, customProcessor, NULL);
     } else if (p1 != P1_MORE) {
@@ -67,7 +67,7 @@ void handleSign(uint8_t p1,
         PRINTF("Signature not initialized\n");
         THROW(0x6985);
     }
-    if (txContext.currentField == TX_RLP_NONE) {
+    if (txContext.currentField == RLP_NONE) {
         PRINTF("Parser not initialized\n");
         THROW(0x6985);
     }
diff --git a/src_features/signTx/logic_signTx.c b/src_features/signTx/logic_signTx.c
index cfbfa8a..8be1d51 100644
--- a/src_features/signTx/logic_signTx.c
+++ b/src_features/signTx/logic_signTx.c
@@ -28,12 +28,18 @@ uint32_t splitBinaryParameterPart(char *result, uint8_t *parameter) {
 }
 
 customStatus_e customProcessor(txContext_t *context) {
-    if ((context->currentField == TX_RLP_DATA) && (context->currentFieldLength != 0)) {
+    if (((context->txType == LEGACY && context->currentField == LEGACY_RLP_DATA) ||
+         (context->txType == EIP2930 && context->currentField == EIP2930_RLP_DATA)) &&
+        (context->currentFieldLength != 0)) {
         dataPresent = true;
         // If handling a new contract rather than a function call, abort immediately
         if (tmpContent.txContent.destinationLength == 0) {
             return CUSTOM_NOT_HANDLED;
         }
+        // If data field is less than 4 bytes long, do not try to use a plugin.
+        if (context->currentFieldLength < 4) {
+            return CUSTOM_NOT_HANDLED;
+        }
         if (context->currentFieldPos == 0) {
             ethPluginInitContract_t pluginInit;
             // If handling the beginning of the data field, assume that the function selector is
@@ -51,6 +57,7 @@ customStatus_e customProcessor(txContext_t *context) {
                                         context->currentFieldLength);
                 dataContext.tokenContext.pluginAvailable =
                     eth_plugin_perform_init(tmpContent.txContent.destination, &pluginInit);
+                PRINTF("a\n");
             }
             PRINTF("pluginAvailable %d\n", dataContext.tokenContext.pluginAvailable);
             if (dataContext.tokenContext.pluginAvailable) {
@@ -238,10 +245,21 @@ void finalizeParsing(bool direct) {
 
     // Verify the chain
     if (chainConfig->chainId != 0) {
-        uint32_t v = getV(&tmpContent.txContent);
-        if (chainConfig->chainId != v) {
+        uint32_t id = 0;
+
+        if (txContext.txType == LEGACY) {
+            id = u32_from_BE(txContext.content->v, txContext.content->vLength);
+        } else if (txContext.txType == EIP2930) {
+            id = u32_from_BE(txContext.content->chainID.value, txContext.content->chainID.length);
+        } else {
+            PRINTF("TxType `%u` not supported while checking for chainID\n", txContext.txType);
+            return;
+        }
+
+        PRINTF("OFFICIAL: %u, RECEIVED: %u\n", chainConfig->chainId, id);
+        if (chainConfig->chainId != id) {
+            PRINTF("Invalid chainID %u expected %u\n", id, chainConfig->chainId);
             reset_app_context();
-            PRINTF("Invalid chainId %d expected %d\n", v, chainConfig->chainId);
             reportFinalizeError(direct);
             if (!direct) {
                 return;
@@ -323,7 +341,6 @@ void finalizeParsing(bool direct) {
     }
 
     if (dataPresent && !N_storage.dataAllowed) {
-        PRINTF("Data field forbidden\n");
         reportFinalizeError(direct);
         if (!direct) {
             return;
@@ -368,6 +385,24 @@ void finalizeParsing(bool direct) {
         compareOrCopy(strings.common.maxFee, displayBuffer, called_from_swap);
     }
 
+    // Prepare chainID field
+    if (genericUI) {
+        if (txContext.txType == LEGACY) {
+            uint32_t id = u32_from_BE(txContext.content->v, txContext.content->vLength);
+            u32_to_str((char *) strings.common.chainID, sizeof(strings.common.chainID), id);
+        } else if (txContext.txType == EIP2930) {
+            uint256_t chainID;
+            convertUint256BE(tmpContent.txContent.chainID.value,
+                             tmpContent.txContent.chainID.length,
+                             &chainID);
+            tostring256(&chainID, 10, displayBuffer, sizeof(displayBuffer));
+            strncpy(strings.common.chainID, displayBuffer, sizeof(strings.common.chainID));
+        } else {
+            PRINTF("Txtype `%u` not supported while generating chainID\n", txContext.txType);
+            return;
+        }
+    }
+
     bool no_consent = false;
 
     no_consent = called_from_swap;
diff --git a/src_features/signTx/ui_common_signTx.c b/src_features/signTx/ui_common_signTx.c
index 23cc80f..54ce048 100644
--- a/src_features/signTx/ui_common_signTx.c
+++ b/src_features/signTx/ui_common_signTx.c
@@ -8,7 +8,7 @@ unsigned int io_seproxyhal_touch_tx_ok(const bagl_element_t *e) {
     uint8_t signatureLength;
     cx_ecfp_private_key_t privateKey;
     uint32_t tx = 0;
-    uint32_t v = getV(&tmpContent.txContent);
+    uint32_t v = u32_from_BE(tmpContent.txContent.v, tmpContent.txContent.vLength);
     io_seproxyhal_io_heartbeat();
     os_perso_derive_node_bip32(CX_CURVE_256K1,
                                tmpCtx.transactionContext.bip32Path,
diff --git a/src_features/signTx/ui_flow_signTx.c b/src_features/signTx/ui_flow_signTx.c
index 477a25a..3edf610 100644
--- a/src_features/signTx/ui_flow_signTx.c
+++ b/src_features/signTx/ui_flow_signTx.c
@@ -1,5 +1,7 @@
 #include "shared_context.h"
 #include "ui_callbacks.h"
+#include "chainConfig.h"
+#include "utils.h"
 
 // clang-format off
 UX_STEP_NOCB(
@@ -85,7 +87,7 @@ UX_FLOW(ux_confirm_parameter_flow,
 
 //////////////////////////////////////////////////////////////////////
 // clang-format off
-UX_STEP_NOCB(ux_approval_tx_1_step,
+UX_STEP_NOCB(ux_approval_review_step,
     pnn,
     {
       &C_icon_eye,
@@ -93,28 +95,35 @@ UX_STEP_NOCB(ux_approval_tx_1_step,
       "transaction",
     });
 UX_STEP_NOCB(
-    ux_approval_tx_2_step,
+    ux_approval_amount_step,
     bnnn_paging,
     {
       .title = "Amount",
       .text = strings.common.fullAmount
     });
 UX_STEP_NOCB(
-    ux_approval_tx_3_step,
+    ux_approval_address_step,
     bnnn_paging,
     {
       .title = "Address",
       .text = strings.common.fullAddress,
     });
 UX_STEP_NOCB(
-    ux_approval_tx_4_step,
+    ux_approval_fees_step,
     bnnn_paging,
     {
       .title = "Max Fees",
       .text = strings.common.maxFee,
     });
+UX_STEP_NOCB(
+    ux_approval_chainid_step,
+    bnnn_paging,
+    {
+      .title = "Chain ID",
+      .text = strings.common.chainID,
+    });
 UX_STEP_CB(
-    ux_approval_tx_5_step,
+    ux_approval_accept_step,
     pbb,
     io_seproxyhal_touch_tx_ok(NULL),
     {
@@ -123,7 +132,7 @@ UX_STEP_CB(
       "and send",
     });
 UX_STEP_CB(
-    ux_approval_tx_6_step,
+    ux_approval_reject_step,
     pb,
     io_seproxyhal_touch_tx_cancel(NULL),
     {
@@ -132,14 +141,14 @@ UX_STEP_CB(
     });
 
 UX_STEP_NOCB(
-    ux_approval_tx_display_nonce_step,
+    ux_approval_nonce_step,
     bnnn_paging,
     {
       .title = "Nonce",
       .text = strings.common.nonce,
     });
 
-UX_STEP_NOCB(ux_approval_tx_data_warning_step,
+UX_STEP_NOCB(ux_approval_data_warning_step,
     pbb,
     {
       &C_icon_warning,
@@ -148,22 +157,35 @@ UX_STEP_NOCB(ux_approval_tx_data_warning_step,
     });
 // clang-format on
 
-const ux_flow_step_t *ux_approval_tx_flow_[9];
+const ux_flow_step_t *ux_approval_tx_flow_[10];
 
 void ux_approve_tx(bool dataPresent) {
     int step = 0;
-    ux_approval_tx_flow_[step++] = &ux_approval_tx_1_step;
+    ux_approval_tx_flow_[step++] = &ux_approval_review_step;
     if (dataPresent && !N_storage.contractDetails) {
-        ux_approval_tx_flow_[step++] = &ux_approval_tx_data_warning_step;
+        ux_approval_tx_flow_[step++] = &ux_approval_data_warning_step;
     }
-    ux_approval_tx_flow_[step++] = &ux_approval_tx_2_step;
-    ux_approval_tx_flow_[step++] = &ux_approval_tx_3_step;
+    ux_approval_tx_flow_[step++] = &ux_approval_amount_step;
+    ux_approval_tx_flow_[step++] = &ux_approval_address_step;
     if (N_storage.displayNonce) {
-        ux_approval_tx_flow_[step++] = &ux_approval_tx_display_nonce_step;
+        ux_approval_tx_flow_[step++] = &ux_approval_nonce_step;
     }
-    ux_approval_tx_flow_[step++] = &ux_approval_tx_4_step;
-    ux_approval_tx_flow_[step++] = &ux_approval_tx_5_step;
-    ux_approval_tx_flow_[step++] = &ux_approval_tx_6_step;
+
+    uint32_t id;
+    if (txContext.txType == LEGACY) {
+        id = u32_from_BE(txContext.content->v, txContext.content->vLength);
+    } else if (txContext.txType == EIP2930) {
+        id = u32_from_BE(txContext.content->chainID.value, txContext.content->chainID.length);
+    } else {
+        PRINTF("TxType `%u` not supported while preparing to approve tx\n", txContext.txType);
+        THROW(0x6501);
+    }
+    if (id != ETHEREUM_MAINNET_CHAINID) {
+        ux_approval_tx_flow_[step++] = &ux_approval_chainid_step;
+    }
+    ux_approval_tx_flow_[step++] = &ux_approval_fees_step;
+    ux_approval_tx_flow_[step++] = &ux_approval_accept_step;
+    ux_approval_tx_flow_[step++] = &ux_approval_reject_step;
     ux_approval_tx_flow_[step++] = FLOW_END_STEP;
 
     ux_flow_init(0, ux_approval_tx_flow_, NULL);

From 81ec019242d87086b7396766334c733cec8a1f34 Mon Sep 17 00:00:00 2001
From: pscott <scott.piriou@ledger.fr>
Date: Wed, 21 Apr 2021 17:04:09 +0200
Subject: [PATCH 12/23] Re-enable plugins

---
 src/eth_plugin_handler.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/eth_plugin_handler.c b/src/eth_plugin_handler.c
index d9f3d5d..ccaa86e 100644
--- a/src/eth_plugin_handler.c
+++ b/src/eth_plugin_handler.c
@@ -59,7 +59,6 @@ void eth_plugin_prepare_query_contract_UI(ethQueryContractUI_t *queryContractUI,
 int eth_plugin_perform_init(uint8_t *contractAddress, ethPluginInitContract_t *init) {
     uint8_t i;
     const uint8_t **selectors;
-    return 0;
     dataContext.tokenContext.pluginAvailable = 0;
     // Handle hardcoded plugin list
     PRINTF("Selector %.*H\n", 4, init->selector);

From dafdc404ac1e14a9b0787ee2e91f2344b3f145bd Mon Sep 17 00:00:00 2001
From: pscott <scott.piriou@ledger.fr>
Date: Wed, 21 Apr 2021 17:07:16 +0200
Subject: [PATCH 13/23] Add strict parameter to u32_from_BE

---
 src/utils.c                            | 8 ++++++--
 src/utils.h                            | 2 +-
 src_features/signTx/logic_signTx.c     | 6 +++---
 src_features/signTx/ui_common_signTx.c | 2 +-
 src_features/signTx/ui_flow_signTx.c   | 4 ++--
 5 files changed, 13 insertions(+), 9 deletions(-)

diff --git a/src/utils.c b/src/utils.c
index 0b7d583..9c16b6f 100644
--- a/src/utils.c
+++ b/src/utils.c
@@ -54,7 +54,8 @@ int local_strchr(char *string, char ch) {
 }
 
 // Almost like U4BE except that it takes `size` as a parameter.
-uint32_t u32_from_BE(uint8_t *in, uint8_t size) {
+// The `strict` parameter defines whether we should throw in case of a length > 4.
+uint32_t u32_from_BE(uint8_t *in, uint8_t size, bool strict) {
     uint32_t res = 0;
     if (size == 1) {
         res = in[0];
@@ -62,8 +63,11 @@ uint32_t u32_from_BE(uint8_t *in, uint8_t size) {
         res = (in[0] << 8) | in[1];
     } else if (size == 3) {
         res = (in[0] << 16) | (in[1] << 8) | in[2];
-    } else {
+    } else if (size == 4) {
         res = (in[0] << 24) | (in[1] << 16) | (in[2] << 8) | in[3];
+    } else if (strict && size != 0) {
+        PRINTF("Unexpected format\n");
+        THROW(EXCEPTION);
     }
     return res;
 }
diff --git a/src/utils.h b/src/utils.h
index 582fb62..b13c5e2 100644
--- a/src/utils.h
+++ b/src/utils.h
@@ -32,7 +32,7 @@ int local_strchr(char* string, char ch);
 void u32_to_str(char* dest, uint8_t dest_size, uint32_t in);
 
 // Converts a list of bytes (in BE) of length `size` to a uint32_t.
-uint32_t u32_from_BE(uint8_t* in, uint8_t size);
+uint32_t u32_from_BE(uint8_t* in, uint8_t size, bool strict);
 
 void amountToString(uint8_t* amount,
                     uint8_t amount_len,
diff --git a/src_features/signTx/logic_signTx.c b/src_features/signTx/logic_signTx.c
index 8be1d51..989331b 100644
--- a/src_features/signTx/logic_signTx.c
+++ b/src_features/signTx/logic_signTx.c
@@ -248,9 +248,9 @@ void finalizeParsing(bool direct) {
         uint32_t id = 0;
 
         if (txContext.txType == LEGACY) {
-            id = u32_from_BE(txContext.content->v, txContext.content->vLength);
+            id = u32_from_BE(txContext.content->v, txContext.content->vLength, true);
         } else if (txContext.txType == EIP2930) {
-            id = u32_from_BE(txContext.content->chainID.value, txContext.content->chainID.length);
+            id = u32_from_BE(txContext.content->chainID.value, txContext.content->chainID.length, false);
         } else {
             PRINTF("TxType `%u` not supported while checking for chainID\n", txContext.txType);
             return;
@@ -388,7 +388,7 @@ void finalizeParsing(bool direct) {
     // Prepare chainID field
     if (genericUI) {
         if (txContext.txType == LEGACY) {
-            uint32_t id = u32_from_BE(txContext.content->v, txContext.content->vLength);
+            uint32_t id = u32_from_BE(txContext.content->v, txContext.content->vLength, true);
             u32_to_str((char *) strings.common.chainID, sizeof(strings.common.chainID), id);
         } else if (txContext.txType == EIP2930) {
             uint256_t chainID;
diff --git a/src_features/signTx/ui_common_signTx.c b/src_features/signTx/ui_common_signTx.c
index 54ce048..ac3023a 100644
--- a/src_features/signTx/ui_common_signTx.c
+++ b/src_features/signTx/ui_common_signTx.c
@@ -8,7 +8,7 @@ unsigned int io_seproxyhal_touch_tx_ok(const bagl_element_t *e) {
     uint8_t signatureLength;
     cx_ecfp_private_key_t privateKey;
     uint32_t tx = 0;
-    uint32_t v = u32_from_BE(tmpContent.txContent.v, tmpContent.txContent.vLength);
+    uint32_t v = u32_from_BE(tmpContent.txContent.v, tmpContent.txContent.vLength, true);
     io_seproxyhal_io_heartbeat();
     os_perso_derive_node_bip32(CX_CURVE_256K1,
                                tmpCtx.transactionContext.bip32Path,
diff --git a/src_features/signTx/ui_flow_signTx.c b/src_features/signTx/ui_flow_signTx.c
index 3edf610..345fef8 100644
--- a/src_features/signTx/ui_flow_signTx.c
+++ b/src_features/signTx/ui_flow_signTx.c
@@ -173,9 +173,9 @@ void ux_approve_tx(bool dataPresent) {
 
     uint32_t id;
     if (txContext.txType == LEGACY) {
-        id = u32_from_BE(txContext.content->v, txContext.content->vLength);
+        id = u32_from_BE(txContext.content->v, txContext.content->vLength, true);
     } else if (txContext.txType == EIP2930) {
-        id = u32_from_BE(txContext.content->chainID.value, txContext.content->chainID.length);
+        id = u32_from_BE(txContext.content->chainID.value, txContext.content->chainID.length, false);
     } else {
         PRINTF("TxType `%u` not supported while preparing to approve tx\n", txContext.txType);
         THROW(0x6501);

From d701f75197e6c414bf376f06067858ba04369466 Mon Sep 17 00:00:00 2001
From: pscott <scott.piriou@ledger.fr>
Date: Wed, 21 Apr 2021 17:09:45 +0200
Subject: [PATCH 14/23] Add comments to u32_from_BE in header file

---
 src/utils.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/utils.h b/src/utils.h
index b13c5e2..b7d3118 100644
--- a/src/utils.h
+++ b/src/utils.h
@@ -31,7 +31,8 @@ int local_strchr(char* string, char ch);
 // `itoa` for uint32_t.
 void u32_to_str(char* dest, uint8_t dest_size, uint32_t in);
 
-// Converts a list of bytes (in BE) of length `size` to a uint32_t.
+// Converts a list of bytes (in BE) of length `size` to a uint32_t. `strict` will make the function
+// throw if the size is > 4.
 uint32_t u32_from_BE(uint8_t* in, uint8_t size, bool strict);
 
 void amountToString(uint8_t* amount,

From fa0dacb44731d7b90b245c464688d7afaba9843c Mon Sep 17 00:00:00 2001
From: pscott <scott.piriou@ledger.fr>
Date: Wed, 21 Apr 2021 17:10:58 +0200
Subject: [PATCH 15/23] Remove printf when parsing chainID

---
 src_common/ethUstream.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src_common/ethUstream.c b/src_common/ethUstream.c
index 22afedc..4cd8f22 100644
--- a/src_common/ethUstream.c
+++ b/src_common/ethUstream.c
@@ -145,7 +145,6 @@ static void processChainID(txContext_t *context) {
         context->currentField++;
         context->processingField = false;
     }
-    PRINTF("chainID: %.*H\n", context->content->chainID.length, context->content->chainID.value);
 }
 
 static void processNonce(txContext_t *context) {

From cac2b9513604b88cb0b4216c941ab086bd40f62a Mon Sep 17 00:00:00 2001
From: pscott <scott.piriou@ledger.fr>
Date: Wed, 21 Apr 2021 17:11:51 +0200
Subject: [PATCH 16/23] Remove printf when parsing legacy tx

---
 src_common/ethUstream.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src_common/ethUstream.c b/src_common/ethUstream.c
index 4cd8f22..06a79d7 100644
--- a/src_common/ethUstream.c
+++ b/src_common/ethUstream.c
@@ -342,7 +342,6 @@ static bool processEIP2930Tx(txContext_t *context) {
 }
 
 static bool processLegacyTx(txContext_t *context) {
-    PRINTF("Processing legacy\n");
     switch (context->currentField) {
         case LEGACY_RLP_CONTENT:
             processContent(context);

From 704c34a5d5162d6723f9573324b25448a0005317 Mon Sep 17 00:00:00 2001
From: pscott <scott.piriou@ledger.fr>
Date: Wed, 21 Apr 2021 17:15:43 +0200
Subject: [PATCH 17/23] Rename to PARSING_IS_DONE

---
 src_common/ethUstream.c | 2 +-
 src_common/ethUstream.h | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/src_common/ethUstream.c b/src_common/ethUstream.c
index 06a79d7..ba1223f 100644
--- a/src_common/ethUstream.c
+++ b/src_common/ethUstream.c
@@ -436,7 +436,7 @@ static parserStatus_e processTxInternal(txContext_t *context) {
     for (;;) {
         customStatus_e customStatus = CUSTOM_NOT_HANDLED;
         // EIP 155 style transaction
-        if (IS_PARSING_DONE(context)) {
+        if (PARSING_IS_DONE(context)) {
             return USTREAM_FINISHED;
         }
         // Old style transaction
diff --git a/src_common/ethUstream.h b/src_common/ethUstream.h
index 531750b..78b10cb 100644
--- a/src_common/ethUstream.h
+++ b/src_common/ethUstream.h
@@ -40,7 +40,7 @@ typedef customStatus_e (*ustreamProcess_t)(struct txContext_t *context);
 // First variant of every Tx enum.
 #define RLP_NONE 0
 
-#define IS_PARSING_DONE(ctx)                                            \
+#define PARSING_IS_DONE(ctx)                                            \
     ((ctx->txType == LEGACY && ctx->currentField == LEGACY_RLP_DONE) || \
      (ctx->txType == EIP2930 && ctx->currentField == EIP2930_RLP_DONE))
 

From 1a1a3198f9643d8edb6dd1bee3adea92d826a6be Mon Sep 17 00:00:00 2001
From: pscott <scott.piriou@ledger.fr>
Date: Wed, 21 Apr 2021 17:17:21 +0200
Subject: [PATCH 18/23] Remove debugggin printf

---
 src_features/signTx/logic_signTx.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src_features/signTx/logic_signTx.c b/src_features/signTx/logic_signTx.c
index 989331b..38dd199 100644
--- a/src_features/signTx/logic_signTx.c
+++ b/src_features/signTx/logic_signTx.c
@@ -57,7 +57,6 @@ customStatus_e customProcessor(txContext_t *context) {
                                         context->currentFieldLength);
                 dataContext.tokenContext.pluginAvailable =
                     eth_plugin_perform_init(tmpContent.txContent.destination, &pluginInit);
-                PRINTF("a\n");
             }
             PRINTF("pluginAvailable %d\n", dataContext.tokenContext.pluginAvailable);
             if (dataContext.tokenContext.pluginAvailable) {

From 11701b6fa2e4f8024b4d558d94fbf50defe0ad7a Mon Sep 17 00:00:00 2001
From: pscott <scott.piriou@ledger.fr>
Date: Wed, 21 Apr 2021 17:19:02 +0200
Subject: [PATCH 19/23] Remove debugging printf

---
 src_features/signTx/logic_signTx.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src_features/signTx/logic_signTx.c b/src_features/signTx/logic_signTx.c
index 38dd199..e7b10cf 100644
--- a/src_features/signTx/logic_signTx.c
+++ b/src_features/signTx/logic_signTx.c
@@ -255,7 +255,6 @@ void finalizeParsing(bool direct) {
             return;
         }
 
-        PRINTF("OFFICIAL: %u, RECEIVED: %u\n", chainConfig->chainId, id);
         if (chainConfig->chainId != id) {
             PRINTF("Invalid chainID %u expected %u\n", id, chainConfig->chainId);
             reset_app_context();

From d5b32af95e12220070e6329e4fa8a8813ea155da Mon Sep 17 00:00:00 2001
From: pscott <scott.piriou@ledger.fr>
Date: Wed, 21 Apr 2021 17:24:54 +0200
Subject: [PATCH 20/23] Clang format

---
 src_features/signTx/logic_signTx.c   | 4 +++-
 src_features/signTx/ui_flow_signTx.c | 3 ++-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/src_features/signTx/logic_signTx.c b/src_features/signTx/logic_signTx.c
index e7b10cf..002f21e 100644
--- a/src_features/signTx/logic_signTx.c
+++ b/src_features/signTx/logic_signTx.c
@@ -249,7 +249,9 @@ void finalizeParsing(bool direct) {
         if (txContext.txType == LEGACY) {
             id = u32_from_BE(txContext.content->v, txContext.content->vLength, true);
         } else if (txContext.txType == EIP2930) {
-            id = u32_from_BE(txContext.content->chainID.value, txContext.content->chainID.length, false);
+            id = u32_from_BE(txContext.content->chainID.value,
+                             txContext.content->chainID.length,
+                             false);
         } else {
             PRINTF("TxType `%u` not supported while checking for chainID\n", txContext.txType);
             return;
diff --git a/src_features/signTx/ui_flow_signTx.c b/src_features/signTx/ui_flow_signTx.c
index 345fef8..31de33d 100644
--- a/src_features/signTx/ui_flow_signTx.c
+++ b/src_features/signTx/ui_flow_signTx.c
@@ -175,7 +175,8 @@ void ux_approve_tx(bool dataPresent) {
     if (txContext.txType == LEGACY) {
         id = u32_from_BE(txContext.content->v, txContext.content->vLength, true);
     } else if (txContext.txType == EIP2930) {
-        id = u32_from_BE(txContext.content->chainID.value, txContext.content->chainID.length, false);
+        id =
+            u32_from_BE(txContext.content->chainID.value, txContext.content->chainID.length, false);
     } else {
         PRINTF("TxType `%u` not supported while preparing to approve tx\n", txContext.txType);
         THROW(0x6501);

From ebffb48cd3a1e063f9353e75e44b893d892484d8 Mon Sep 17 00:00:00 2001
From: pscott <scott.piriou@ledger.fr>
Date: Wed, 28 Apr 2021 10:48:18 +0200
Subject: [PATCH 21/23] Use snprintf instead of u32_to_str

---
 src/utils.c                        | 39 ------------------------------
 src/utils.h                        |  3 ---
 src_features/signTx/logic_signTx.c |  8 +++++-
 3 files changed, 7 insertions(+), 43 deletions(-)

diff --git a/src/utils.c b/src/utils.c
index 9c16b6f..b319736 100644
--- a/src/utils.c
+++ b/src/utils.c
@@ -72,45 +72,6 @@ uint32_t u32_from_BE(uint8_t *in, uint8_t size, bool strict) {
     return res;
 }
 
-// Converts a uint32_t to a string.
-void u32_to_str(char *dest, uint32_t in, uint8_t dest_size) {
-    uint8_t i = 0;
-
-    // Get the first digit (in case it's 0).
-    dest[i] = in % 10 + '0';
-    in /= 10;
-    i++;
-
-    // Get every digit.
-    while (in != 0) {
-        if (i >= dest_size) {
-            THROW(6502);
-        }
-        dest[i] = in % 10 + '0';
-        in /= 10;
-        i++;
-    }
-
-    // Null terminate the string.
-    dest[i] = '\0';
-    i--;
-
-    // Reverse the string
-    uint8_t end = i;
-    char tmp;
-    i = 0;
-    while (i < end) {
-        // Swap the first and last elements.
-        tmp = dest[i];
-        dest[i] = dest[end];
-        dest[end] = tmp;
-
-        // Decrease the interval size.
-        i++;
-        end--;
-    }
-}
-
 void amountToString(uint8_t *amount,
                     uint8_t amount_size,
                     uint8_t decimals,
diff --git a/src/utils.h b/src/utils.h
index b7d3118..ba878e1 100644
--- a/src/utils.h
+++ b/src/utils.h
@@ -28,9 +28,6 @@ void convertUint256BE(uint8_t* data, uint32_t length, uint256_t* target);
 
 int local_strchr(char* string, char ch);
 
-// `itoa` for uint32_t.
-void u32_to_str(char* dest, uint8_t dest_size, uint32_t in);
-
 // Converts a list of bytes (in BE) of length `size` to a uint32_t. `strict` will make the function
 // throw if the size is > 4.
 uint32_t u32_from_BE(uint8_t* in, uint8_t size, bool strict);
diff --git a/src_features/signTx/logic_signTx.c b/src_features/signTx/logic_signTx.c
index 002f21e..9a5dc42 100644
--- a/src_features/signTx/logic_signTx.c
+++ b/src_features/signTx/logic_signTx.c
@@ -389,7 +389,13 @@ void finalizeParsing(bool direct) {
     if (genericUI) {
         if (txContext.txType == LEGACY) {
             uint32_t id = u32_from_BE(txContext.content->v, txContext.content->vLength, true);
-            u32_to_str((char *) strings.common.chainID, sizeof(strings.common.chainID), id);
+            uint8_t res =
+                snprintf(strings.common.chainID, sizeof(strings.common.chainID), "%u", id);
+            if (res >= sizeof(strings.common.chainID)) {
+                // If the return value is higher or equal to the size passed in as parameter, then
+                // the output was truncated. Return the appropriate error code.
+                THROW(0x6502);
+            }
         } else if (txContext.txType == EIP2930) {
             uint256_t chainID;
             convertUint256BE(tmpContent.txContent.chainID.value,

From 7f0afc764a3fa837a8f1128bf851f2552f5c385f Mon Sep 17 00:00:00 2001
From: pscott <scott.piriou@ledger.fr>
Date: Wed, 28 Apr 2021 10:48:37 +0200
Subject: [PATCH 22/23] Change error code description

---
 doc/ethapp.asc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/doc/ethapp.asc b/doc/ethapp.asc
index ac716dd..d35664c 100644
--- a/doc/ethapp.asc
+++ b/doc/ethapp.asc
@@ -474,7 +474,7 @@ The following standard Status Words are returned for all APDUs - some specific S
 |===============================================================================================
 | *SW*     | *Description*
 |   6501   | TransactionType not supported
-|   6502   | Not enough space for conversion from uint32_t to string
+|   6502   | Output buffer too small for snprintf input
 |   6700   | Incorrect length
 |   6982   | Security status not satisfied (Canceled by user)
 |   6A80   | Invalid data

From c7ec0c7dfaa88d3060bbf526d529aec74af157f7 Mon Sep 17 00:00:00 2001
From: pscott <scott.piriou@ledger.fr>
Date: Wed, 28 Apr 2021 11:39:47 +0200
Subject: [PATCH 23/23] Use %d flag instead of %u

---
 src_features/signTx/logic_signTx.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src_features/signTx/logic_signTx.c b/src_features/signTx/logic_signTx.c
index 9a5dc42..e392a54 100644
--- a/src_features/signTx/logic_signTx.c
+++ b/src_features/signTx/logic_signTx.c
@@ -389,8 +389,9 @@ void finalizeParsing(bool direct) {
     if (genericUI) {
         if (txContext.txType == LEGACY) {
             uint32_t id = u32_from_BE(txContext.content->v, txContext.content->vLength, true);
+            PRINTF("Chain ID: %u\n", id);
             uint8_t res =
-                snprintf(strings.common.chainID, sizeof(strings.common.chainID), "%u", id);
+                snprintf(strings.common.chainID, sizeof(strings.common.chainID), "%d", id);
             if (res >= sizeof(strings.common.chainID)) {
                 // If the return value is higher or equal to the size passed in as parameter, then
                 // the output was truncated. Return the appropriate error code.