Merge pull request #447 from LedgerHQ/fix/apa/eip712

Fix EIP-712 improper handling of empty arrays

Author: apaillier-ledger

src_features/signMessageEIP712/commands_712.c

@@ -13,7 +13,8 @@
 #include "schema_hash.h"
 #include "filtering.h"
 #include "common_712.h"
-#include "ethUtils.h"  // allzeroes
+#include "ethUtils.h"   // allzeroes
+#include "common_ui.h"  // ui_idle
 
 /**
  * Send the response to the previous APDU command
@@ -38,6 +39,7 @@ void handle_eip712_return_code(bool success) {
 
     if (!success) {
         eip712_context_deinit();
+        ui_idle();
     }
 }
 

src_features/signMessageEIP712/path.c

@@ -143,14 +143,18 @@ static cx_sha3_t *get_last_hash_ctx(void) {
  * Finalize the last hashing context
  *
  * @param[out] hash pointer to buffer where the hash will be stored
+ * @return whether there was anything hashed at this depth
  */
-static void finalize_hash_depth(uint8_t *hash) {
+static bool finalize_hash_depth(uint8_t *hash) {
     const cx_sha3_t *hash_ctx;
+    size_t hashed_bytes;
 
     hash_ctx = get_last_hash_ctx();
+    hashed_bytes = hash_ctx->blen;
     // finalize hash
     cx_hash((cx_hash_t *) hash_ctx, CX_LAST, NULL, 0, hash, KECCAK256_HASH_BYTESIZE);
     mem_dealloc(sizeof(*hash_ctx));  // remove hash context
+    return hashed_bytes > 0;
 }
 
 /**
@@ -192,6 +196,7 @@ static bool push_new_hash_depth(bool init) {
  */
 static bool path_depth_list_pop(void) {
     uint8_t hash[KECCAK256_HASH_BYTESIZE];
+    bool to_feed;
 
     if (path_struct == NULL) {
         return false;
@@ -201,9 +206,11 @@ static bool path_depth_list_pop(void) {
     }
     path_struct->depth_count -= 1;
 
-    finalize_hash_depth(hash);
+    to_feed = finalize_hash_depth(hash);
     if (path_struct->depth_count > 0) {
-        feed_last_hash_depth(hash);
+        if (to_feed) {
+            feed_last_hash_depth(hash);
+        }
     } else {
         switch (path_struct->root_type) {
             case ROOT_DOMAIN:
@@ -261,7 +268,7 @@ static bool array_depth_list_pop(void) {
         return false;
     }
 
-    finalize_hash_depth(hash);
+    finalize_hash_depth(hash);  // return value not checked on purpose
     feed_last_hash_depth(hash);
 
     path_struct->array_depth_count -= 1;
@@ -307,7 +314,10 @@ static bool path_update(void) {
         }
         feed_last_hash_depth(hash);
 
-        ui_712_queue_struct_to_review();
+        // TODO: Find a better way to show inner structs in verbose mode when it might be
+        //       an empty array of structs in which case we don't want to show it but the
+        //       size is only known later
+        // ui_712_queue_struct_to_review();
         path_depth_list_push();
     }
     return true;
@@ -421,6 +431,8 @@ bool path_new_array_depth(const uint8_t *const data, uint8_t length) {
     uint8_t total_count = 0;
     uint8_t pidx;
     bool is_custom;
+    uint8_t array_size;
+    uint8_t array_depth_count_bak;
 
     if (path_struct == NULL) {
         apdu_response_code = APDU_RESPONSE_CONDITION_NOT_SATISFIED;
@@ -430,6 +442,8 @@ bool path_new_array_depth(const uint8_t *const data, uint8_t length) {
         return false;
     }
 
+    array_size = *data;
+    array_depth_count_bak = path_struct->array_depth_count;
     for (pidx = 0; pidx < path_struct->depth_count; ++pidx) {
         if ((field_ptr = get_nth_field(NULL, pidx + 1)) == NULL) {
             apdu_response_code = APDU_RESPONSE_CONDITION_NOT_SATISFIED;
@@ -442,7 +456,7 @@ bool path_new_array_depth(const uint8_t *const data, uint8_t length) {
             }
             total_count += depth_count;
             if (total_count > path_struct->array_depth_count) {
-                if (!check_and_add_array_depth(depth, total_count, pidx, *data)) {
+                if (!check_and_add_array_depth(depth, total_count, pidx, array_size)) {
                     return false;
                 }
                 break;
@@ -463,9 +477,18 @@ bool path_new_array_depth(const uint8_t *const data, uint8_t length) {
         cx_sha3_t *hash_ctx = get_last_hash_ctx();
         cx_sha3_t *old_ctx = hash_ctx - 1;
 
-        memcpy(hash_ctx, old_ctx, sizeof(*old_ctx));
+        if (array_size > 0) {
+            memcpy(hash_ctx, old_ctx, sizeof(*old_ctx));
+        } else {
+            cx_keccak_init(hash_ctx, 256);
+        }
         cx_keccak_init(old_ctx, 256);  // init hash
     }
+    if (array_size == 0) {
+        do {
+            path_advance();
+        } while (path_struct->array_depth_count != array_depth_count_bak);
+    }
 
     return true;
 }
@@ -515,7 +538,7 @@ static bool path_advance_in_array(void) {
 
         if ((path_struct->array_depth_count > 0) &&
             (arr_depth->path_index == (path_struct->depth_count - 1))) {
-            arr_depth->size -= 1;
+            if (arr_depth->size > 0) arr_depth->size -= 1;
             if (arr_depth->size == 0) {
                 array_depth_list_pop();
                 end_reached = true;

src_nbgl/ui_message_signing.c

@@ -1,6 +1,6 @@
 #include "ui_nbgl.h"
 #include "ui_signing.h"
-#include "common_712.h"
+#include "ui_logic.h"
 #include "ui_message_signing.h"
 #include "glyphs.h"
 
@@ -42,9 +42,9 @@ void ui_message_start(const char *title,
 }
 
 void ui_message_712_approved(void) {
-    ui_712_approve_cb();
+    ui_712_approve();
 }
 
 void ui_message_712_rejected(void) {
-    ui_712_reject_cb();
+    ui_712_reject();
 }

tests/ragger/eip712/input_files/13-empty_arrays-data.json

@@ -0,0 +1,37 @@
+{
+    "domain": {
+        "chainId": 5,
+        "name": "Empty Arrays",
+        "verifyingContract": "0xCcCCccccCCCCcCCCCCCcCcCccCcCCCcCcccccccC",
+        "version": "1"
+    },
+    "message": {
+        "list1": [],
+        "list2": [],
+        "list3": [
+            [
+                "1",
+                "2"
+            ],
+            [],
+            [
+                "3",
+                "4"
+            ]
+        ]
+    },
+    "primaryType": "Struct",
+    "types": {
+        "EIP712Domain": [
+            { "name": "name", "type": "string" },
+            { "name": "version", "type": "string" },
+            { "name": "chainId", "type": "uint256" },
+            { "name": "verifyingContract", "type": "address" }
+        ],
+        "Struct": [
+            { "name": "list1", "type": "EIP712Domain[]" },
+            { "name": "list2", "type": "uint8[]" },
+            { "name": "list3", "type": "string[][]" }
+        ]
+    }
+}

tests/ragger/eip712/input_files/13-empty_arrays.ini

@@ -0,0 +1,4 @@
+[signature]
+v = 1b
+r = 5d0635a868602e29366da6328f8fadf2d6a9b4e69ee7a65928e85ca56fb1b515
+s = 257364d6faaf5687edf90c3984f4240b0ce7b2dee55aa1f8f39c32d0d4d8c93d