Can now read a chain ID from the swap sub coin config

src/handle_get_printable_amount.c

@@ -7,32 +7,32 @@
 #include "common_utils.h"
 #include "uint256.h"
 #include "string.h"
+#include "network.h"
 
 void handle_get_printable_amount(get_printable_amount_parameters_t* params,
                                  chain_config_t* config) {
-    uint8_t decimals;
     char ticker[MAX_TICKER_LEN];
+    uint8_t decimals;
+    uint64_t chain_id = 0;
+
     memset(params->printable_amount, 0, sizeof(params->printable_amount));
     if (params->amount_length > 32) {
         PRINTF("Amount is too big, 32 bytes max but buffer has %u bytes", params->amount_length);
         return;
     }
 
-    // If the amount is a fee, its value is nominated in ETH even if we're doing an ERC20 swap
+    if (!parse_swap_config(params->coin_configuration,
+                           params->coin_configuration_length,
+                           ticker,
+                           &decimals,
+                           &chain_id)) {
+        PRINTF("Error while parsing config\n");
+        return;
+    }
+    // If the amount is a fee, the ticker should be the chain's native currency
     if (params->is_fee) {
-        uint8_t ticker_len = strnlen(config->coinName, sizeof(config->coinName));
-        memcpy(ticker, config->coinName, ticker_len);
-        ticker[ticker_len] = '\0';
+        strlcpy(ticker, get_displayable_ticker(&chain_id, config), sizeof(ticker));
         decimals = WEI_TO_ETHER;
-    } else {
-        // If the amount is *not* a fee, decimals and ticker are built from the given config
-        if (!parse_swap_config(params->coin_configuration,
-                               params->coin_configuration_length,
-                               ticker,
-                               &decimals)) {
-            PRINTF("Error while parsing config\n");
-            return;
-        }
     }
 
     if (!amountToString(params->amount,

src/handle_swap_sign_transaction.c

@@ -5,6 +5,7 @@
 #include "handle_swap_sign_transaction.h"
 #include "shared_context.h"
 #include "common_utils.h"
+#include "network.h"
 #ifdef HAVE_NBGL
 #include "nbgl_use_case.h"
 #endif  // HAVE_NBGL
@@ -27,12 +28,15 @@ bool copy_transaction_parameters(create_transaction_parameters_t* sign_transacti
         return false;
     }
 
-    uint8_t decimals;
     char ticker[MAX_TICKER_LEN];
+    uint8_t decimals;
+    uint64_t chain_id = 0;
+
     if (!parse_swap_config(sign_transaction_params->coin_configuration,
                            sign_transaction_params->coin_configuration_length,
                            ticker,
-                           &decimals)) {
+                           &decimals,
+                           &chain_id)) {
         PRINTF("Error while parsing config\n");
         return false;
     }
@@ -46,7 +50,7 @@ bool copy_transaction_parameters(create_transaction_parameters_t* sign_transacti
     }
 
     // If the amount is a fee, its value is nominated in ETH even if we're doing an ERC20 swap
-    strlcpy(ticker, config->coinName, MAX_TICKER_LEN);
+    strlcpy(ticker, get_displayable_ticker(&chain_id, config), sizeof(ticker));
     decimals = WEI_TO_ETHER;
     if (!amountToString(sign_transaction_params->fee_amount,
                         sign_transaction_params->fee_amount_length,

src/swap_utils.c

@@ -22,22 +22,38 @@
 #include "asset_info.h"
 #include "swap_utils.h"
 
-bool parse_swap_config(const uint8_t *config, uint8_t config_len, char *ticker, uint8_t *decimals) {
+bool parse_swap_config(const uint8_t *config,
+                       uint8_t config_len,
+                       char *ticker,
+                       uint8_t *decimals,
+                       uint64_t *chain_id) {
     uint8_t ticker_len, offset = 0;
+
     if (config_len == 0) {
         return false;
     }
-    ticker_len = config[offset++];
-    if (ticker_len == 0 || ticker_len > MAX_TICKER_LEN - 2 || config_len - offset < ticker_len) {
+    ticker_len = config[offset];
+    offset += sizeof(ticker_len);
+    if ((ticker_len == 0) || (ticker_len > (MAX_TICKER_LEN - 2)) ||
+        ((config_len - offset) < (ticker_len))) {
         return false;
     }
     memcpy(ticker, config + offset, ticker_len);
     offset += ticker_len;
     ticker[ticker_len] = '\0';
 
-    if (config_len - offset < 1) {
+    if ((config_len - offset) < 1) {
         return false;
     }
     *decimals = config[offset];
+    offset += sizeof(*decimals);
+
+    // the chain ID was adder later to the CAL swap subconfig
+    // so it is optional for retro-compatibility (as it might not be present)
+    if ((config_len - offset) >= sizeof(*chain_id)) {
+        PRINTF("Chain ID from the swap subconfig = 0x%.*h\n", sizeof(*chain_id), &config[offset]);
+        *chain_id = u64_from_BE(config + offset, sizeof(*chain_id));
+        offset += sizeof(*chain_id);
+    }
     return true;
 }

src/swap_utils.h

@@ -19,4 +19,8 @@
 
 #include <stdint.h>
 
-bool parse_swap_config(const uint8_t* config, uint8_t config_len, char* ticker, uint8_t* decimals);
+bool parse_swap_config(const uint8_t* config,
+                       uint8_t config_len,
+                       char* ticker,
+                       uint8_t* decimals,
+                       uint64_t* chain_id);