Diff: main.cpp

Revision:

0:f43431023689

Child:

1:b88ef7630eb3

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Sat Jul 20 15:16:38 2019 +0000
@@ -0,0 +1,384 @@
+#include "mbed.h"
+#include "helpers.h"
+
+// bitcoin lib
+#include "Bitcoin.h"
+#include "PSBT.h"
+
+/*********** forward declarations **************/
+
+// generates a new mnemonic
+string generateNewMnemonic();
+
+// generates hd keys from the mnemonic
+void initKeys(const string mnemonic, const string password = "");
+
+/****************** GUI classes ****************/
+
+Label titleLbl;
+Label dataLbl;
+QR qr;
+
+Button btn;
+Button printBtn;
+Label lbl;
+
+/***************** GUI functions ***************/
+
+// if mnemonic is not present we can generate or recover it
+void showInitScreen();
+// if mnemonic is there we go directly to the main menu
+void showMenu();
+// handy function to display information to the user
+// with a title, a message and OK button that goes to the menu
+void showMessage(const string title, const string message);
+static lv_res_t toMenuCallback(lv_obj_t * btn);
+static lv_res_t showAddressesCallback(lv_obj_t * btn);
+static lv_res_t saveXpubCallback(lv_obj_t * btn);
+static lv_res_t signPSBTCallback(lv_obj_t * btn);
+static lv_res_t showMnemonicCallback(lv_obj_t * btn);
+static lv_res_t wipeCallback(lv_obj_t * btn);
+static lv_res_t newMnemonicCallback(lv_obj_t * btn);
+static lv_res_t enterMnemonicCallback(lv_obj_t * btn);
+void showAddress(unsigned int child_index, bool change);
+
+/***************** bitcoin keys ***************/
+
+HDPrivateKey root; // root private key
+HDPrivateKey account; // account master private key
+HDPublicKey xpub; // account master public key
+bool change = false; // internal or external address
+unsigned int child_index = 0; // current child index
+
+PSBT psbt; // psbt transaction we will be signing
+
+/******************* Main part *****************/
+
+int main(){
+    init();
+
+    string mnemonic = loadMnemonic();
+    if(mnemonic.length() == 0){
+        showInitScreen();
+    }else{
+        initKeys(mnemonic);
+        showMenu();
+    }
+
+    while(1){
+        gui.update();
+    }
+} 
+
+/****************** GUI stuff *****************/
+void showInitScreen(){
+    gui.clear();
+    titleLbl = Label("Let's set it up!");
+    titleLbl.size(gui.width(), 20);
+    titleLbl.position(0, 40);
+    titleLbl.alignText(ALIGN_TEXT_CENTER);
+
+    Button btn(newMnemonicCallback, "Generate new mnemonic");
+    btn.size(gui.width()-100, 80);
+    btn.position(0, 200);
+    btn.align(ALIGN_CENTER);
+
+    Button btn2(enterMnemonicCallback, "Enter existing mnemonic");
+    btn2.size(gui.width()-100, 80);
+    btn2.position(0, 300);
+    btn2.align(ALIGN_CENTER);
+}
+
+void showMenu(){
+    gui.clear();
+    titleLbl = Label("What do you want to do?");
+    titleLbl.size(gui.width(), 20);
+    titleLbl.position(0, 40);
+    titleLbl.alignText(ALIGN_TEXT_CENTER);
+
+    Button btn(showAddressesCallback, "Show addresses");
+    btn.size(gui.width()-100, 80);
+    btn.position(0, 100);
+    btn.align(ALIGN_CENTER);
+
+    Button btn2(saveXpubCallback, "Export xpub");
+    btn2.size(gui.width()-100, 80);
+    btn2.position(0, 300);
+    btn2.align(ALIGN_CENTER);
+
+    Button btn3(signPSBTCallback, "Sign PSBT transaction");
+    btn3.size(gui.width()-100, 80);
+    btn3.position(0, 400);
+    btn3.align(ALIGN_CENTER);
+
+    Button btn4(wipeCallback, "Wipe device");
+    btn4.size(gui.width()-100, 80);
+    btn4.position(0, 600);
+    btn4.align(ALIGN_CENTER);
+
+    Button btn5(showMnemonicCallback, "Show mnemonic");
+    btn5.size(gui.width()-100, 80);
+    btn5.position(0, 700);
+    btn5.align(ALIGN_CENTER);
+}
+
+void showMessage(const string title, const string message){
+    gui.clear();
+    titleLbl = Label(title);
+    titleLbl.size(gui.width(), 20);
+    titleLbl.position(0, 40);
+    titleLbl.alignText(ALIGN_TEXT_CENTER);
+
+    dataLbl = Label(message);
+    dataLbl.size(gui.width()-100, 100);
+    dataLbl.position(50, 300);
+    dataLbl.alignText(ALIGN_TEXT_CENTER);
+
+    Button btn(toMenuCallback, "OK");
+    btn.size(gui.width()-100, 80);
+    btn.position(0, gui.height()-100);
+    btn.align(ALIGN_CENTER);
+}
+
+static lv_res_t nextCallback(lv_obj_t * btn){
+    child_index++;
+    showAddress(child_index, change);
+    return LV_RES_OK;
+}
+static lv_res_t prevCallback(lv_obj_t * btn){
+    if(child_index > 0){
+        child_index--;
+        showAddress(child_index, change);
+    }
+    return LV_RES_OK;
+}
+static lv_res_t changeCallback(lv_obj_t * btn){
+    change = !change;
+    showAddress(child_index, change);
+    return LV_RES_OK;
+}
+static lv_res_t xpubCallback(lv_obj_t * btn){
+    titleLbl.text("Your master public key");
+    qr.text(xpub.toString());
+    dataLbl.text(xpub.toString());
+    qr.align(ALIGN_CENTER);
+    dataLbl.align(ALIGN_CENTER);
+    return LV_RES_OK;
+}
+
+void showAddress(unsigned int child_index, bool change){
+    stringstream title;
+    title << "Your ";
+    if(change){
+        title << "change ";
+    }else{
+        title << "receiving ";
+    }
+    title << "address #" << child_index << ":";
+    titleLbl.text(title.str());
+    string address = xpub.child(change).child(child_index).address();
+    dataLbl.text(address);
+    dataLbl.align(ALIGN_CENTER);
+    qr.text(string("bitcoin:") + address);
+    qr.align(ALIGN_CENTER);
+}
+
+void showAddressScreen(){
+    gui.clear();
+    titleLbl = Label("Your address");
+    titleLbl.size(gui.width(), 20);
+    titleLbl.position(0, 40);
+    titleLbl.alignText(ALIGN_TEXT_CENTER);
+
+    dataLbl = Label(" ");
+    dataLbl.size(gui.width()-100, 100); // full width
+    dataLbl.position(50, gui.height()-300);
+    dataLbl.alignText(ALIGN_TEXT_CENTER);
+
+    qr = QR(" ");
+    qr.size(gui.width()-100);
+    qr.position(0, 100);
+    qr.align(ALIGN_CENTER);
+
+    Button btn(nextCallback, "Next address");
+    btn.size(gui.width()/3-20, 80);
+    btn.position(gui.width()*2/3 + 10, gui.height()-100);
+
+    Button btn2(prevCallback, "Previous address");
+    btn2.size(gui.width()/3-20, 80);
+    btn2.position(10, gui.height()-100);
+
+    Button btn3(changeCallback, "Toggle\nchange");
+    btn3.size(gui.width()/3-20, 80);
+    btn3.position(gui.width()/3 + 10, gui.height()-100);
+
+    Button btn4(xpubCallback, "Show xpub");
+    btn4.size(gui.width()/2-20, 80);
+    btn4.position(gui.width()/2+10, gui.height()-200);
+
+    Button btn5(toMenuCallback, "Menu");
+    btn5.size(gui.width()/2-20, 80);
+    btn5.position(10, gui.height()-200);
+}
+
+static lv_res_t toMenuCallback(lv_obj_t * btn){
+    showMenu();
+    return LV_RES_OK;
+}
+
+static lv_res_t showAddressesCallback(lv_obj_t * btn){
+    showAddressScreen();
+    showAddress(child_index, change);
+    return LV_RES_OK;
+}
+static lv_res_t saveXpubCallback(lv_obj_t * btn){
+    // TODO: 
+    // - check if SD card present
+    // - save xpub to the "xpub.txt"
+    // - check if write was sucessful
+    // - show success / fail message
+    if(!SD.detected()){
+        showMessage("Error", "SD card is not present");
+        return LV_RES_OK;
+    }
+    int res = SD.save("xpub.txt", xpub.toString());
+    if(res != SD_SUCCESS){
+        showMessage("Error", "Something wrong with SD card");
+        return LV_RES_OK;
+    }
+    showMessage("Success","Master public key is saved to the SD card");
+    return LV_RES_OK;
+}
+static lv_res_t signConfirmCallback(lv_obj_t * btn){    
+    if(!SD.detected()){
+        showMessage("Error", "SD card is not present");
+        return LV_RES_OK;
+    }
+    psbt.sign(account);
+
+    uint8_t * raw = (uint8_t *)calloc(psbt.length(), sizeof(uint8_t));
+    size_t len = psbt.serialize(raw, psbt.length());
+    psbt = PSBT();
+    // cout << len << endl;
+    char * b64 = (char *)calloc(2*len+1, sizeof(char));
+    len = toBase64(raw, len, b64, 2*len+1);
+    free(raw);
+
+    int res = SD.save("signed.psbt", b64);
+    free(b64);
+    if(res != SD_SUCCESS){
+        showMessage("Error", "Something wrong with SD card");
+        return LV_RES_OK;
+    }
+    showMessage("Success", "Signed transaction saved to the SD card");
+    return LV_RES_OK;
+}
+void showSignRequest(){
+    stringstream ss;
+    ss << "Sending:\n\n";
+    for(unsigned int i=0; i<psbt.tx.outputsNumber; i++){
+        // TODO: better to put it into PSBT method like check_output or something
+        bool mine = false;
+        if(psbt.txOutsMeta[i].derivationsLen > 0){
+            for(unsigned int j=0; j<psbt.txOutsMeta[i].derivationsLen; j++){
+                HDPrivateKey prv = account.derive(psbt.txOutsMeta[i].derivations[j].derivation, psbt.txOutsMeta[i].derivations[j].derivationLen);
+                PublicKey pub = prv.publicKey();
+                // TODO: fix public key comparison
+                if(pub.toString() == psbt.txOutsMeta[i].derivations[j].pubkey.toString()){
+                    mine = true;
+                }
+            }
+        }
+        ss << psbt.tx.txOuts[i].address(&Testnet);
+        if(mine){
+            ss << " (change)";
+        }
+        ss << ": " << (float(psbt.tx.txOuts[i].amount)/1e5) << " mBTC\n\n";
+    }
+    ss << "Fee: " << (float(psbt.fee())/1e5) << " mBTC";
+
+    gui.clear();
+    titleLbl = Label("Sign transaction?");
+    titleLbl.size(gui.width(), 20);
+    titleLbl.position(0, 40);
+    titleLbl.alignText(ALIGN_TEXT_CENTER);
+
+    dataLbl = Label(ss.str());
+    dataLbl.size(gui.width()-100, 100);
+    dataLbl.position(50, 300);
+    dataLbl.alignText(ALIGN_TEXT_CENTER);
+
+    Button btn(toMenuCallback, "Cancel");
+    btn.size(gui.width()/2-45, 80);
+    btn.position(30, gui.height()-100);
+
+    Button btn2(signConfirmCallback, "Confirm");
+    btn2.size(gui.width()/2-45, 80);
+    btn2.position(gui.width()/2+30, gui.height()-100);
+}
+static lv_res_t signPSBTCallback(lv_obj_t * btn){
+    if(!SD.detected()){
+        showMessage("Error", "SD card is not present");
+        return LV_RES_OK;
+    }
+    string s = SD.read("unsigned.psbt");
+    if(s.length() == 0){
+        showMessage("Fail", "Can't read unsigned.psbt file");
+        return LV_RES_OK;
+    }
+    uint8_t raw[1000];
+    unsigned int len = fromBase64(s.c_str(), s.length(), raw, sizeof(raw));
+    if(len == 0){
+        showMessage("Fail", "Can't convert from base64");
+        return LV_RES_OK;
+    }
+    psbt.reset();
+    len = psbt.parse(raw, len);
+    if(len == 0){
+        showMessage("Fail", "Can't parse PSBT");
+        return LV_RES_OK;
+    }
+    showSignRequest();
+    return LV_RES_OK;
+}
+static lv_res_t wipeCallback(lv_obj_t * btn){
+    wipe();
+    return LV_RES_OK;
+}
+
+/*************** mnemonic stuff ***************/
+
+static lv_res_t newMnemonicCallback(lv_obj_t * btn){
+    // TODO: 
+    // - generate random buffer (16 or 32 bytes)
+    // - create a new mnemonic from it
+    // - save this mnemonic
+    // - display it to the user
+    uint8_t randomBuffer[16];
+    getRandomBuffer(randomBuffer, sizeof(randomBuffer));
+    string mnemonic = generateMnemonic(randomBuffer, sizeof(randomBuffer));
+    saveMnemonic(mnemonic);
+    showMessage("Write down your recovery phrase:", mnemonic);
+    initKeys(mnemonic);
+    return LV_RES_OK;
+}
+
+static lv_res_t showMnemonicCallback(lv_obj_t * btn){
+    string mnemonic = loadMnemonic();
+    showMessage("Here is your recovery phrase:", mnemonic);
+    return LV_RES_OK;
+}
+
+static lv_res_t enterMnemonicCallback(lv_obj_t * btn){
+    return LV_RES_OK;
+}
+
+void initKeys(const string mnemonic, const string password){
+    // TODO:
+    // - derive root key from the mnemonic and empty password
+    // - derive account key using m/84'/1'/0'/ derivation path
+    // - get account master public key
+    root.fromMnemonic(mnemonic, password);
+    account = root.derive("m/84'/1'/0'/");
+    xpub = account.xpub();
+}