messaging: remove fixed output buffer from 'reply_to_message_result()'

Remove 'MAX_STANDARD_OUTPUT_MSG_SIZE' buffer from stack.  Have the
caller pass a buffer appropriately sized for cbor serialisation into
this call, consistent with the other calls for sending replies/messages.
Place large buffers onto the heap.

Author: Jamie C. Driver

main/process.c

@@ -541,29 +541,33 @@ void cbor_result_uint64_cb(const void* ctx, CborEncoder* container)
     JADE_ASSERT(cberr == CborNoError);
 }
 
-void jade_process_reply_to_message_result(const cbor_msg_t ctx, const void* cbctx, cbor_encoder_fn_t cb)
+void jade_process_reply_to_message_result(
+    const cbor_msg_t ctx, uint8_t* output, size_t output_size, const void* cbctx, cbor_encoder_fn_t cb)
 {
     JADE_ASSERT(cb);
+    JADE_ASSERT(output);
+    JADE_ASSERT(output_size);
 
     char id[MAXLEN_ID + 1];
     size_t written = 0;
     rpc_get_id(&ctx.value, id, sizeof(id), &written);
     JADE_ASSERT(written != 0);
 
-    uint8_t buf[MAX_STANDARD_OUTPUT_MSG_SIZE];
-    jade_process_reply_to_message_result_with_id(id, buf, sizeof(buf), ctx.source, cbctx, cb);
+    jade_process_reply_to_message_result_with_id(id, output, output_size, ctx.source, cbctx, cb);
 }
 
 void jade_process_reply_to_message_ok(jade_process_t* process)
 {
+    uint8_t buf[64];
     const bool ok = true;
-    jade_process_reply_to_message_result(process->ctx, &ok, cbor_result_boolean_cb);
+    jade_process_reply_to_message_result(process->ctx, buf, sizeof(buf), &ok, cbor_result_boolean_cb);
 }
 
 void jade_process_reply_to_message_fail(jade_process_t* process)
 {
+    uint8_t buf[64];
     const bool ok = false;
-    jade_process_reply_to_message_result(process->ctx, &ok, cbor_result_boolean_cb);
+    jade_process_reply_to_message_result(process->ctx, buf, sizeof(buf), &ok, cbor_result_boolean_cb);
 }
 
 void jade_process_reject_message_with_id(const char* id, int code, const char* message, const uint8_t* data,

main/process.h

@@ -95,7 +95,8 @@ void jade_process_push_out_message(const uint8_t* data, size_t length, jade_msg_
 // Send message replies
 void jade_process_reply_to_message_result_with_id(const char* id, uint8_t* output, size_t output_size,
     jade_msg_source_t source, const void* cbctx, cbor_encoder_fn_t cb);
-void jade_process_reply_to_message_result(const cbor_msg_t ctx, const void* cbctx, cbor_encoder_fn_t cb);
+void jade_process_reply_to_message_result(
+    const cbor_msg_t ctx, uint8_t* output, size_t output_size, const void* cbctx, cbor_encoder_fn_t cb);
 void jade_process_reply_to_message_ok(jade_process_t* process);
 void jade_process_reply_to_message_fail(jade_process_t* process);
 void jade_process_reply_to_message_ex(jade_msg_source_t source, const uint8_t* reply_payload, size_t payload_len);

main/process/dashboard.c

@@ -250,7 +250,10 @@ void set_request_change_pin(bool change_pin);
 static void process_get_version_info_request(jade_process_t* process)
 {
     ASSERT_CURRENT_MESSAGE(process, "get_version_info");
-    jade_process_reply_to_message_result(process->ctx, &process->ctx.source, build_version_info_reply);
+
+    uint8_t buf[1024];
+    jade_process_reply_to_message_result(
+        process->ctx, buf, sizeof(buf), &process->ctx.source, build_version_info_reply);
 }
 
 // If the user has successfully authenticated over a given connection interface,
@@ -515,7 +518,10 @@ static void dispatch_message(jade_process_t* process)
         if (debug_selfcheck(process)) {
             const TickType_t end_time = xTaskGetTickCount();
             const uint64_t elapsed_time_ms = (end_time - start_time) * portTICK_PERIOD_MS;
-            jade_process_reply_to_message_result(process->ctx, &elapsed_time_ms, cbor_result_uint64_cb);
+
+            uint8_t buf[64];
+            jade_process_reply_to_message_result(
+                process->ctx, buf, sizeof(buf), &elapsed_time_ms, cbor_result_uint64_cb);
         } else {
             jade_process_reject_message(process, CBOR_RPC_INTERNAL_ERROR, "ERROR", NULL);
         }

main/process/debug_scan_qr.c

@@ -185,8 +185,9 @@ void debug_scan_qr_process(void* process_ptr)
     }
 
     // Reply with the decoded data (empty if failed)
+    uint8_t buf[512]; // sufficient for all existing test cases
     const bytes_info_t bytes_info = { .data = qr_data.data, .size = qr_data.len };
-    jade_process_reply_to_message_result(process->ctx, &bytes_info, cbor_result_bytes_cb);
+    jade_process_reply_to_message_result(process->ctx, buf, sizeof(buf), &bytes_info, cbor_result_bytes_cb);
     JADE_LOGI("Success");
 
 cleanup:

main/process/get_bip85_entropy.c

@@ -302,7 +302,8 @@ void get_bip85_bip39_entropy_process(void* process_ptr)
     }
 
     // Reply with the encrypted bip85 entropy reply
-    jade_process_reply_to_message_result(process->ctx, &bip85_data, reply_bip85_data);
+    uint8_t buf[256];
+    jade_process_reply_to_message_result(process->ctx, buf, sizeof(buf), &bip85_data, reply_bip85_data);
     JADE_LOGI("Success");
 
 cleanup:
@@ -328,7 +329,8 @@ void get_bip85_rsa_entropy_process(void* process_ptr)
     }
 
     // Reply with the encrypted bip85 entropy reply
-    jade_process_reply_to_message_result(process->ctx, &bip85_data, reply_bip85_data);
+    uint8_t buf[256];
+    jade_process_reply_to_message_result(process->ctx, buf, sizeof(buf), &bip85_data, reply_bip85_data);
     JADE_LOGI("Success");
 
 cleanup:

main/process/get_bip85_pubkey.c

@@ -29,14 +29,15 @@ void get_bip85_pubkey_process(void* process_ptr)
 
     display_processing_message_activity();
 
-    char pubkey_pem[1024];
+    char pubkey_pem[896];
     if (!rsa_get_bip85_pubkey_pem(key_bits, index, pubkey_pem, sizeof(pubkey_pem))) {
         jade_process_reject_message(process, CBOR_RPC_INTERNAL_ERROR, "Failed to generate RSA key", NULL);
         goto cleanup;
     }
 
     // Reply with the pubkey pem
-    jade_process_reply_to_message_result(process->ctx, pubkey_pem, cbor_result_string_cb);
+    uint8_t buf[1024];
+    jade_process_reply_to_message_result(process->ctx, buf, sizeof(buf), pubkey_pem, cbor_result_string_cb);
     JADE_LOGI("Success");
 
 cleanup:

main/process/get_commitments.c

@@ -128,7 +128,9 @@ void get_commitments_process(void* process_ptr)
     }
 
     commitments.content = COMMITMENTS_ABF | COMMITMENTS_VBF | COMMITMENTS_INCLUDES_COMMITMENTS;
-    jade_process_reply_to_message_result(process->ctx, &commitments, reply_commitments);
+
+    uint8_t buf[320];
+    jade_process_reply_to_message_result(process->ctx, buf, sizeof(buf), &commitments, reply_commitments);
 
     JADE_LOGI("Success");
 

main/process/get_otp_code.c

@@ -94,7 +94,8 @@ void get_otp_code_process(void* process_ptr)
     }
     JADE_LOGD("User pressed accept");
 
-    jade_process_reply_to_message_result(process->ctx, token, cbor_result_string_cb);
+    uint8_t buf[64];
+    jade_process_reply_to_message_result(process->ctx, buf, sizeof(buf), token, cbor_result_string_cb);
 
     JADE_LOGI("Success");
 

main/process/get_receive_address.c

@@ -267,7 +267,8 @@ void get_receive_address_process(void* process_ptr)
     }
 
     // Reply with the address
-    jade_process_reply_to_message_result(process->ctx, address, cbor_result_string_cb);
+    uint8_t buf[256];
+    jade_process_reply_to_message_result(process->ctx, buf, sizeof(buf), address, cbor_result_string_cb);
 
     JADE_LOGI("Success");
 

main/process/get_registered_descriptor.c

@@ -95,9 +95,12 @@ void get_registered_descriptor_process(void* process_ptr)
     }
 
     // Reply with this info
+    const size_t buflen = 1024 + (128 * descriptor_data.num_values);
+    uint8_t* const buf = JADE_MALLOC(buflen);
     const descriptor_details_t descriptor_details
         = { .descriptor_name = descriptor_name, .descriptor_data = &descriptor_data };
-    jade_process_reply_to_message_result(process->ctx, &descriptor_details, reply_registered_descriptor);
+    jade_process_reply_to_message_result(process->ctx, buf, buflen, &descriptor_details, reply_registered_descriptor);
+    free(buf);
 
     JADE_LOGI("Success");