Swap SPL Tokens

src/apdu_parser.c

@@ -103,6 +103,14 @@ static uint16_t check_instruction(uint8_t instruction, uint8_t subcommand) {
             check_current_state = TRANSACTION_RECEIVED;
             check_subcommand_context = true;
             break;
+        case GET_CHALLENGE:
+            check_current_state = SIGNATURE_CHECKED;
+            check_subcommand_context = true;
+            break;
+        case SEND_TRUSTED_NAME_DESCRIPTOR:
+            check_current_state = CHALLENGE_SENT;
+            check_subcommand_context = true;
+            break;
         case CHECK_PAYOUT_ADDRESS:
         case CHECK_ASSET_IN_AND_DISPLAY:
         case CHECK_ASSET_IN_NO_DISPLAY:

src/command_dispatcher.c

@@ -12,6 +12,8 @@
 #include "start_signing_transaction.h"
 #include "check_addresses_and_amounts.h"
 #include "prompt_ui_display.h"
+#include "get_challenge_handler.h"
+#include "trusted_name_descriptor_handler.h"
 
 #include "io.h"
 
@@ -42,6 +44,12 @@ int dispatch_command(const command_t *cmd) {
         case CHECK_TRANSACTION_SIGNATURE_COMMAND:
             ret = check_tx_signature(cmd);
             break;
+        case GET_CHALLENGE:
+            ret = get_challenge_handler();
+            break;
+        case SEND_TRUSTED_NAME_DESCRIPTOR:
+            ret = trusted_name_descriptor_handler(cmd);
+            break;
         case CHECK_PAYOUT_ADDRESS:
         case CHECK_ASSET_IN_AND_DISPLAY:
         case CHECK_ASSET_IN_NO_DISPLAY:

src/commands.h

@@ -13,6 +13,8 @@ typedef enum {
     CHECK_PARTNER_COMMAND = 0x05,
     PROCESS_TRANSACTION_RESPONSE_COMMAND = 0x06,
     CHECK_TRANSACTION_SIGNATURE_COMMAND = 0x07,
+    GET_CHALLENGE = 0x10,
+    SEND_TRUSTED_NAME_DESCRIPTOR = 0x11,
     CHECK_PAYOUT_ADDRESS = 0x08,
     CHECK_ASSET_IN_LEGACY_AND_DISPLAY = 0x08,  // Same ID as CHECK_PAYOUT_ADDRESS, deprecated
     CHECK_ASSET_IN_AND_DISPLAY = 0x0B,         // Do note the 0x0B

src/get_challenge_handler.c

@@ -0,0 +1,55 @@
+#include <cx.h>
+#include "get_challenge_handler.h"
+#include "swap_errors.h"
+#include "buffer.h"
+#include "io.h"
+#include "globals.h"
+
+static uint32_t challenge;
+
+#define LAST_BYTE_MASK 0x000000FF
+
+/**
+ * Generate a new challenge from the Random Number Generator
+ */
+void roll_challenge(void) {
+#ifdef HAVE_TRUSTED_NAME_TEST
+    challenge = 0xdeadbeef;
+#else
+    challenge = cx_rng_u32();
+#endif
+}
+
+/**
+ * Get the current challenge
+ *
+ * @return challenge
+ */
+uint32_t get_challenge(void) {
+    return challenge;
+}
+
+/**
+ * Send back the current challenge
+ */
+int get_challenge_handler(void) {
+    PRINTF("New challenge -> %u\n", challenge);
+    uint8_t output_buffer[4];
+    output_buffer[0] = (uint8_t) ((challenge >> 24) & LAST_BYTE_MASK);
+    output_buffer[1] = (uint8_t) ((challenge >> 16) & LAST_BYTE_MASK);
+    output_buffer[2] = (uint8_t) ((challenge >> 8) & LAST_BYTE_MASK);
+    output_buffer[3] = (uint8_t) (challenge & LAST_BYTE_MASK);
+
+    buffer_t output;
+    output.ptr = output_buffer;
+    output.size = 4;
+    output.offset = 0;
+
+    if (io_send_response_buffers(&output, 1, SUCCESS) < 0) {
+        return -1;
+    }
+
+    G_swap_ctx.state = CHALLENGE_SENT;
+
+    return 0;
+}

src/get_challenge_handler.h

@@ -0,0 +1,5 @@
+#pragma once
+
+void roll_challenge(void);
+uint32_t get_challenge(void);
+int get_challenge_handler(void);

src/main.c

@@ -29,6 +29,7 @@
 #include "swap_errors.h"
 #include "apdu_parser.h"
 #include "sign_result.h"
+#include "get_challenge_handler.h"
 
 #include "usbd_core.h"
 
@@ -155,6 +156,9 @@ __attribute__((section(".boot"))) int main(__attribute__((unused)) int arg0) {
                 BLE_power(1, NULL);
 #endif
 
+                // to prevent it from having a fixed value at boot
+                roll_challenge();
+
                 app_main();
             }
             CATCH(SWO_SEC_APP_14) {

src/states.h

@@ -7,6 +7,8 @@ typedef enum {
     PROVIDER_CHECKED,
     TRANSACTION_RECEIVED,
     SIGNATURE_CHECKED,
+    CHALLENGE_SENT,
+    TRUSTED_NAME_DESCRIPTOR_RECEIVED,
     PAYOUT_ADDRESS_CHECKED,
     ALL_ADDRESSES_CHECKED,
     WAITING_USER_VALIDATION,