Fix visability issues.

Fix #6 . Fix relying party verification.
Fix to throw error when relying party uses the wrong application parameter when requesting a signature.
2019-09-14 09:24:03 +01:00 · 2019-09-11 15:49:50 +01:00 · 2019-09-10 10:52:02 +01:00 · 2019-09-10 10:51:32 +01:00 · 2019-09-09 17:06:47 +01:00 · 2019-09-08 20:27:47 +01:00
57 changed files with 1062 additions and 1119 deletions
--- a/.clang-format
+++ b/.clang-format
@@ -0,0 +1,24 @@
+---
+BasedOnStyle: llvm
+IndentWidth: 4
+---
+AccessModifierOffset: -4
+AllowShortFunctionsOnASingleLine: Empty
+AlwaysBreakTemplateDeclarations: Yes
+BreakBeforeBraces: Attach
+BreakConstructorInitializers: BeforeColon
+Cpp11BracedListStyle: false
+ColumnLimit: 100
+DerivePointerAlignment: false
+FixNamespaceComments: true
+IndentCaseLabels: true
+IndentPPDirectives: AfterHash
+Language: Cpp
+PointerAlignment: Left
+SortIncludes: true
+SortUsingDeclarations: true
+Standard: Cpp11
+TabWidth: 4
+UseTab: ForIndentation
+
+...
--- a/.gitignore
+++ b/.gitignore
@@ -3,3 +3,8 @@ libcppb64.a
 U2FDevice
 obj/*
 U2F_Priv_Keys.txt
+.ccls-cache
+compile_commands.json
+Certificates.hpp
+Certificates.cpp
+Keys/*
--- a/APDU.hpp
+++ b/APDU.hpp
@@ -18,15 +18,9 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.

 #pragma once

-enum APDU : uint8_t
-{
-	U2F_REG  = 0x01,
-	U2F_AUTH = 0x02,
-	U2F_VER  = 0x03
-};
+enum APDU : uint8_t { U2F_REG = 0x01, U2F_AUTH = 0x02, U2F_VER = 0x03 };

-enum APDU_STATUS : uint16_t
-{
+enum APDU_STATUS : uint16_t {
 	SW_NO_ERROR = 0x9000,
 	SW_WRONG_LENGTH = 0x6700,
 	SW_CONDITIONS_NOT_SATISFIED = 0x6985,
--- a/Architecture.hpp
+++ b/Architecture.hpp
@@ -20,7 +20,7 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.

 #define ARCH_RASPBERRY_PI 1
 #define ARCH_ANDROID 2
-#define ARCHITECTURE ARCH_ANDROID
+#define ARCHITECTURE ARCH_RASPBERRY_PI

 #if ARCHITECTURE == ARCH_RASPBERRY_PI
 #	define STORAGE_PREFIX "/usr/share/"
--- a/Base64.hpp
+++ b/Base64.hpp
@@ -31,7 +31,9 @@ template <typename InContainer, typename Elem, size_t count>
 void b64decode(const InContainer& iContainer, std::array<Elem, count>& oArr);

 template <typename InContainerIter, typename OutContainerIter>
-void b64encode(const InContainerIter beginIter, const InContainerIter endIter, OutContainerIter oBeginIter);
+void b64encode(const InContainerIter beginIter, const InContainerIter endIter,
+               OutContainerIter oBeginIter);

 template <typename InContainerIter, typename OutContainerIter>
-void b64decode(const InContainerIter beginIter, const InContainerIter endIter, OutContainerIter oBeginIter);
+void b64decode(const InContainerIter beginIter, const InContainerIter endIter,
+               OutContainerIter oBeginIter);
--- a/Certificates.cpp
+++ b/Certificates.cpp
@@ -1,90 +0,0 @@
-/*
-U2FDevice - A program to allow Raspberry Pi Zeros to act as U2F tokens
-Copyright (C) 2018  Michael Kuc
-
-This program is free software: you can redistribute it and/or modify
-it under the terms of the GNU General Public License as published by
-the Free Software Foundation, either version 3 of the License, or
-(at your option) any later version.
-
-This program is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-GNU General Public License for more details.
-
-You should have received a copy of the GNU General Public License
-along with this program.  If not, see <https://www.gnu.org/licenses/>.
-*/
-    
-#include "Certificates.hpp"
-
-//You may not actually want to use these values -
-// having been shared publicly, these may be vulnerable to exploits.
-// However, generating your own attestation certificate makes your device
-// uniquely identifiable across platforms / services, etc.
-// You can generate your own using the method detailed in the README.
-
-uint8_t attestCert[] = {
-	0x30, 0x82, 0x02, 0x29, 0x30, 0x82, 0x01, 0xd0, 0xa0, 0x03, 0x02, 0x01,
-	0x02, 0x02, 0x09, 0x00, 0x8a, 0xe2, 0x21, 0x3f, 0x2f, 0x8b, 0x72, 0x52,
-	0x30, 0x0a, 0x06, 0x08, 0x2a, 0x86, 0x48, 0xce, 0x3d, 0x04, 0x03, 0x02,
-	0x30, 0x70, 0x31, 0x0b, 0x30, 0x09, 0x06, 0x03, 0x55, 0x04, 0x06, 0x13,
-	0x02, 0x55, 0x4b, 0x31, 0x13, 0x30, 0x11, 0x06, 0x03, 0x55, 0x04, 0x08,
-	0x0c, 0x0a, 0x53, 0x6f, 0x6d, 0x65, 0x2d, 0x53, 0x74, 0x61, 0x74, 0x65,
-	0x31, 0x21, 0x30, 0x1f, 0x06, 0x03, 0x55, 0x04, 0x0a, 0x0c, 0x18, 0x49,
-	0x6e, 0x74, 0x65, 0x72, 0x6e, 0x65, 0x74, 0x20, 0x57, 0x69, 0x64, 0x67,
-	0x69, 0x74, 0x73, 0x20, 0x50, 0x74, 0x79, 0x20, 0x4c, 0x74, 0x64, 0x31,
-	0x29, 0x30, 0x27, 0x06, 0x03, 0x55, 0x04, 0x03, 0x0c, 0x20, 0x55, 0x32,
-	0x46, 0x20, 0x4b, 0x65, 0x79, 0x20, 0x74, 0x50, 0x46, 0x53, 0x71, 0x54,
-	0x71, 0x6f, 0x5a, 0x6d, 0x62, 0x37, 0x38, 0x61, 0x6a, 0x6f, 0x2f, 0x75,
-	0x58, 0x50, 0x73, 0x51, 0x3d, 0x3d, 0x30, 0x1e, 0x17, 0x0d, 0x31, 0x38,
-	0x30, 0x36, 0x33, 0x30, 0x31, 0x39, 0x30, 0x37, 0x35, 0x31, 0x5a, 0x17,
-	0x0d, 0x32, 0x38, 0x30, 0x36, 0x32, 0x37, 0x31, 0x39, 0x30, 0x37, 0x35,
-	0x31, 0x5a, 0x30, 0x70, 0x31, 0x0b, 0x30, 0x09, 0x06, 0x03, 0x55, 0x04,
-	0x06, 0x13, 0x02, 0x55, 0x4b, 0x31, 0x13, 0x30, 0x11, 0x06, 0x03, 0x55,
-	0x04, 0x08, 0x0c, 0x0a, 0x53, 0x6f, 0x6d, 0x65, 0x2d, 0x53, 0x74, 0x61,
-	0x74, 0x65, 0x31, 0x21, 0x30, 0x1f, 0x06, 0x03, 0x55, 0x04, 0x0a, 0x0c,
-	0x18, 0x49, 0x6e, 0x74, 0x65, 0x72, 0x6e, 0x65, 0x74, 0x20, 0x57, 0x69,
-	0x64, 0x67, 0x69, 0x74, 0x73, 0x20, 0x50, 0x74, 0x79, 0x20, 0x4c, 0x74,
-	0x64, 0x31, 0x29, 0x30, 0x27, 0x06, 0x03, 0x55, 0x04, 0x03, 0x0c, 0x20,
-	0x55, 0x32, 0x46, 0x20, 0x4b, 0x65, 0x79, 0x20, 0x74, 0x50, 0x46, 0x53,
-	0x71, 0x54, 0x71, 0x6f, 0x5a, 0x6d, 0x62, 0x37, 0x38, 0x61, 0x6a, 0x6f,
-	0x2f, 0x75, 0x58, 0x50, 0x73, 0x51, 0x3d, 0x3d, 0x30, 0x59, 0x30, 0x13,
-	0x06, 0x07, 0x2a, 0x86, 0x48, 0xce, 0x3d, 0x02, 0x01, 0x06, 0x08, 0x2a,
-	0x86, 0x48, 0xce, 0x3d, 0x03, 0x01, 0x07, 0x03, 0x42, 0x00, 0x04, 0x32,
-	0x41, 0xc3, 0xb8, 0x96, 0x97, 0xd8, 0x90, 0x66, 0x41, 0x88, 0x96, 0xd4,
-	0x73, 0xb6, 0x37, 0xf7, 0x85, 0x29, 0xaf, 0x3b, 0x15, 0x0f, 0x83, 0x61,
-	0x67, 0xea, 0xc9, 0xb2, 0xdb, 0x82, 0xb3, 0x2c, 0x99, 0x60, 0x8a, 0x98,
-	0x7c, 0xd4, 0x04, 0xa0, 0x92, 0x22, 0x05, 0xaa, 0xf7, 0x7a, 0x91, 0x02,
-	0x03, 0xdd, 0x15, 0x88, 0x87, 0x6a, 0x26, 0xe9, 0xee, 0xcf, 0x99, 0xb1,
-	0x66, 0xc0, 0x01, 0xa3, 0x53, 0x30, 0x51, 0x30, 0x1d, 0x06, 0x03, 0x55,
-	0x1d, 0x0e, 0x04, 0x16, 0x04, 0x14, 0xcf, 0x7f, 0xfa, 0x7d, 0xc4, 0x8d,
-	0xba, 0x60, 0x52, 0x4c, 0xb6, 0x16, 0x2e, 0x88, 0x62, 0xc7, 0x8c, 0xfc,
-	0xe0, 0x63, 0x30, 0x1f, 0x06, 0x03, 0x55, 0x1d, 0x23, 0x04, 0x18, 0x30,
-	0x16, 0x80, 0x14, 0xcf, 0x7f, 0xfa, 0x7d, 0xc4, 0x8d, 0xba, 0x60, 0x52,
-	0x4c, 0xb6, 0x16, 0x2e, 0x88, 0x62, 0xc7, 0x8c, 0xfc, 0xe0, 0x63, 0x30,
-	0x0f, 0x06, 0x03, 0x55, 0x1d, 0x13, 0x01, 0x01, 0xff, 0x04, 0x05, 0x30,
-	0x03, 0x01, 0x01, 0xff, 0x30, 0x0a, 0x06, 0x08, 0x2a, 0x86, 0x48, 0xce,
-	0x3d, 0x04, 0x03, 0x02, 0x03, 0x47, 0x00, 0x30, 0x44, 0x02, 0x20, 0x72,
-	0x25, 0x89, 0xc1, 0x32, 0x54, 0x66, 0xf8, 0x0e, 0x58, 0x77, 0xe3, 0xb5,
-	0x62, 0x47, 0x33, 0x18, 0x5a, 0xdc, 0x28, 0x6a, 0x4a, 0x56, 0xcb, 0x58,
-	0x63, 0xe3, 0xa1, 0x02, 0x6a, 0xf0, 0xd8, 0x02, 0x20, 0x65, 0x26, 0x84,
-	0x7c, 0xc3, 0x3b, 0x7d, 0x6a, 0x22, 0x0c, 0x22, 0x3d, 0xc8, 0x43, 0xb7,
-	0x84, 0x8b, 0x7b, 0x48, 0x23, 0xb0, 0x1e, 0x13, 0x35, 0x1d, 0x1a, 0x90,
-	0x44, 0x62, 0x6c, 0xab, 0x9b
-};
-
-uint8_t attestPrivKey[] = {
-	0x7e, 0xbd, 0x91, 0x05, 0x5a, 0x80, 0x9f, 0x36, 0xe5, 0x2f, 0xe0, 0xd0,
-	0xa9, 0x63, 0x0c, 0x86, 0x04, 0xb1, 0x04, 0xe3, 0xd1, 0xfb, 0xd0, 0x83,
-	0xc7, 0x2e, 0x2f, 0x34, 0xb6, 0xd6, 0xa4, 0xb2
-};
-
-uint8_t attestPubKey[] = {
-	0x04, 0x32, 0x41, 0xc3, 0xb8, 0x96, 0x97, 0xd8, 0x90, 0x66, 0x41, 0x88,
-	0x96, 0xd4, 0x73, 0xb6, 0x37, 0xf7, 0x85, 0x29, 0xaf, 0x3b, 0x15, 0x0f,
-	0x83, 0x61, 0x67, 0xea, 0xc9, 0xb2, 0xdb, 0x82, 0xb3, 0x2c, 0x99, 0x60,
-	0x8a, 0x98, 0x7c, 0xd4, 0x04, 0xa0, 0x92, 0x22, 0x05, 0xaa, 0xf7, 0x7a,
-	0x91, 0x02, 0x03, 0xdd, 0x15, 0x88, 0x87, 0x6a, 0x26, 0xe9, 0xee, 0xcf,
-	0x99, 0xb1, 0x66, 0xc0, 0x01
-};
--- a/Certificates.cpp.template
+++ b/Certificates.cpp.template
@@ -0,0 +1,37 @@
+/*
+U2FDevice - A program to allow Raspberry Pi Zeros to act as U2F tokens
+Copyright (C) 2018  Michael Kuc
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <https://www.gnu.org/licenses/>.
+*/
+
+#include "Certificates.hpp"
+
+// You may not actually want to use these values -
+// having been shared publicly, these may be vulnerable to exploits.
+// However, generating your own attestation certificate makes your device
+// uniquely identifiable across platforms / services, etc.
+// You can generate your own using the method detailed in the README.
+
+uint8_t attestCert[] = {
+	// Generate attestation certificate here
+};
+
+uint8_t attestPrivKey[] = {
+	// Generate private key here
+};
+
+uint8_t attestPubKey[] = {
+	// Generate public key here
+};
--- a/Certificates.hpp.template
+++ b/Certificates.hpp.template
@@ -19,6 +19,6 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 #pragma once
 #include <cstdint>

-extern uint8_t attestCert[557];
-extern uint8_t attestPrivKey[32];
-extern uint8_t attestPubKey[65];
+extern uint8_t attestCert[/* attestation certificate size */];
+extern uint8_t attestPrivKey[/* attestation private key size */];
+extern uint8_t attestPubKey[/* attestation public key size */];
--- a/Channel.cpp
+++ b/Channel.cpp
@@ -17,24 +17,24 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

 #include "Channel.hpp"
-#include <stdexcept>
-#include "u2f.hpp"
+#include "Storage.hpp"
 #include "U2F_CMD.hpp"
+#include "u2f.hpp"
 #include <iostream>
+#include <stdexcept>

 using namespace std;

 Channel::Channel(const uint32_t channelID)
-	: cid{ channelID }, initState{ ChannelInitState::Unitialised }, lockedState{ ChannelLockedState::Unlocked }
-{}
+    : cid{ channelID }, initState{ ChannelInitState::Unitialised }, lockedState{
+	      ChannelLockedState::Unlocked
+      } {}

-uint32_t Channel::getCID() const
-{
+uint32_t Channel::getCID() const {
 	return cid;
 }

-void Channel::handle(const shared_ptr<U2FMessage> uMsg)
-{
+void Channel::handle(const shared_ptr<U2FMessage> uMsg) {
 	if (uMsg->cmd == U2FHID_INIT)
 		this->initState = ChannelInitState::Initialised;
 	else if (uMsg->cid != this->cid)
@@ -47,16 +47,18 @@ void Channel::handle(const shared_ptr<U2FMessage> uMsg)

 	auto cmd = U2F_CMD::get(uMsg);

-	if (cmd)
-		return cmd->respond(this->cid);
+	if (cmd) {
+		cmd->respond(this->cid);
+
+		if (cmd->modifiesPersistentState())
+			Storage::save();
+	}
 }

-void Channel::init(const ChannelInitState newInitState)
-{
+void Channel::init(const ChannelInitState newInitState) {
 	this->initState = newInitState;
 }

-void Channel::lock(const ChannelLockedState newLockedState)
-{
+void Channel::lock(const ChannelLockedState newLockedState) {
 	this->lockedState = newLockedState;
 }
--- a/Channel.hpp
+++ b/Channel.hpp
@@ -17,24 +17,15 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

 #pragma once
+#include "U2FMessage.hpp"
 #include <cstdint>
 #include <memory>
-#include "U2FMessage.hpp"

-enum class ChannelInitState
-{
-	Unitialised,
-	Initialised
-};
+enum class ChannelInitState { Unitialised, Initialised };

-enum class ChannelLockedState
-{
-	Locked,
-	Unlocked
-};
+enum class ChannelLockedState { Locked, Unlocked };

-class Channel
-{
+class Channel {
 protected:
 	uint32_t cid;
 	ChannelInitState initState;
--- a/Controller.cpp
+++ b/Controller.cpp
@@ -17,28 +17,25 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

 #include "Controller.hpp"
-#include "u2f.hpp"
-#include <iostream>
 #include "IO.hpp"
 #include "LED.hpp"
+#include "u2f.hpp"
+#include <iostream>

 using namespace std;

-Controller::Controller(const uint32_t startChannel)
-	: channels{}, currChannel{ startChannel }
-{}
+Controller::Controller(const uint32_t startChannel) : channels{}, currChannel{ startChannel } {}

-void Controller::handleTransaction()
-{
-	try
-	{
-		if (channels.size() != 0 && chrono::duration_cast<chrono::seconds>(chrono::system_clock::now() - lastMessage) < chrono::seconds(5))
+void Controller::handleTransaction() {
+	try {
+		if (channels.size() != 0 &&
+		    chrono::duration_cast<chrono::seconds>(chrono::system_clock::now() - lastMessage) <
+		        chrono::seconds(5))
 			toggleACTLED();
 		else
 			enableACTLED(false);
+	} catch (runtime_error& ignored) {
 	}
-	catch (runtime_error& ignored)
-	{}

 	auto msg = U2FMessage::readNonBlock();

@@ -47,21 +44,20 @@ void Controller::handleTransaction()

 	lastMessage = chrono::system_clock::now();

-	auto opChannel = msg->cid;
+	auto opChannelID = msg->cid;

-	if (msg->cmd == U2FHID_INIT)
-	{
-		opChannel = nextChannel();
-		auto channel = Channel{ opChannel };
+	if (msg->cmd == U2FHID_INIT) {
+		opChannelID = nextChannel();
+		auto channel = Channel{ opChannelID };

-		try
-		{
-			channels.emplace(opChannel, channel); //In case of wrap-around replace existing one
-		}
-		catch (...)
-		{
-			channels.insert(make_pair(opChannel, channel));
+		try {
+			channels.emplace(opChannelID, channel); // In case of wrap-around replace existing one
+		} catch (...) {
+			channels.insert(make_pair(opChannelID, channel));
 		}
+	} else if (channels.find(opChannelID) == channels.end()) {
+		U2FMessage::error(opChannelID, ERR_CHANNEL_BUSY);
+		return;
 	}

 #ifdef DEBUG_MSGS
@@ -69,11 +65,10 @@ void Controller::handleTransaction()
 	clog << "cid: " << msg->cid << ", cmd: " << static_cast<unsigned int>(msg->cmd) << endl;
 #endif

-	channels.at(opChannel).handle(msg);
+	channels.at(opChannelID).handle(msg);
 }

-uint32_t Controller::nextChannel()
-{
+uint32_t Controller::nextChannel() {
 	do
 		currChannel++;
 	while (currChannel == 0xFFFFFFFF || currChannel == 0);
--- a/Controller.hpp
+++ b/Controller.hpp
@@ -17,12 +17,11 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

 #pragma once
-#include <map>
-#include <chrono>
 #include "Channel.hpp"
+#include <chrono>
+#include <map>

-class Controller
-{
+class Controller {
 protected:
 	std::map<uint32_t, Channel> channels;
 	uint32_t currChannel;
--- a/Field.cpp
+++ b/Field.cpp
@@ -20,7 +20,7 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.

 using namespace std;

-vector<uint8_t> beEncode(const uint8_t* val, const size_t byteCount)
-{
-	return { reverse_iterator<const uint8_t *>(val + byteCount), reverse_iterator<const uint8_t *>(val) };
+vector<uint8_t> beEncode(const uint8_t* val, const size_t byteCount) {
+	return { reverse_iterator<const uint8_t*>(val + byteCount),
+		     reverse_iterator<const uint8_t*>(val) };
 }
--- a/Field.hpp
+++ b/Field.hpp
@@ -17,13 +17,17 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

 #pragma once
-#include <vector>
 #include <cstdint>
+#include <vector>

 template <typename Type>
 std::vector<uint8_t> beEncode(const Type val);

 std::vector<uint8_t> beEncode(const uint8_t* val, const std::size_t byteCount);

-#define FIELD(name) reinterpret_cast<const uint8_t*>(&name), (reinterpret_cast<const uint8_t*>(&name) + sizeof(name))
-#define FIELD_BE(name) reverse_iterator<const uint8_t*>(reinterpret_cast<const uint8_t*>(&name) + sizeof(name)), reverse_iterator<const uint8_t*>(reinterpret_cast<const uint8_t*>(&name))
+#define FIELD(name)                                                                                \
+	reinterpret_cast<const uint8_t*>(&name),                                                       \
+	    (reinterpret_cast<const uint8_t*>(&name) + sizeof(name))
+#define FIELD_BE(name)                                                                             \
+	reverse_iterator<const uint8_t*>(reinterpret_cast<const uint8_t*>(&name) + sizeof(name)),      \
+	    reverse_iterator<const uint8_t*>(reinterpret_cast<const uint8_t*>(&name))
--- a/GenCertificates.sh
+++ b/GenCertificates.sh
@@ -0,0 +1,31 @@
+#!/usr/bin/env sh
+
+sed --version | grep "GNU" 2>&1 1>/dev/null
+if [ $? -ne 0 ]; then
+	printf "Requires the GNU version of SED.\n"
+	return -1
+fi
+
+[ -d Keys ] || mkdir Keys
+
+openssl ecparam -name prime256v1 -genkey -noout -out Keys/ecprivkey.pem
+openssl ec -in Keys/ecprivkey.pem -pubout -out Keys/ecpubkey.pem 2>/dev/null
+openssl req -new -x509 -key Keys/ecprivkey.pem -out Keys/certificate.pem -days 3650
+openssl x509 -outform der -in Keys/certificate.pem -out Keys/certificate.der 2>/dev/null
+
+certificate="$(xxd --include Keys/certificate.der | sed -e '0,/{/d;/};/,$d' -e 's/^\s\+/\t/g')"
+certificateSize="$(printf "%s" "${certificate}" | wc -w)"
+printf "%s" "${certificate}" | sed -e '/\/\/ Generate attestation certificate here/{r/dev/stdin
+d }' Certificates.cpp.template > Keys/Certificates.cpp.template.1
+
+privkey="$(openssl ec -in Keys/ecprivkey.pem -pubout -text -noout 2>/dev/null | sed -e '0,/priv:/d;/pub:/,$d' -e 's/\s//g;s/:/, /g;' -e 's/^/\t/g;s/\s\+$//g' -e 's/\(\s\)/\10x/g')"
+privSize="$(printf "%s" "${privkey}" | wc -w)"
+printf "%s\n" "${privkey}" | sed -e '/\/\/ Generate private key here/{r/dev/stdin
+d }' Keys/Certificates.cpp.template.1 > Keys/Certificates.cpp.template.2
+
+pubkey="$(openssl ec -in Keys/ecprivkey.pem -pubout -text -noout 2>/dev/null | sed -e '0,/pub:/d;/ASN1/,$d' -e 's/\s//g;s/:/, /g;' -e 's/^/\t/g;s/\s\+$//g' -e 's/\(\s\)/\10x/g')"
+pubSize="$(printf "%s" "${pubkey}" | wc -w)"
+printf "%s\n" "${pubkey}" | sed -e '/\/\/ Generate public key here/{r/dev/stdin
+d }' Keys/Certificates.cpp.template.2 > Certificates.cpp
+
+sed -e "s/\\/\\* attestation certificate size \\*\\//${certificateSize}/; s/\\/\\* attestation private key size \\*\\//${privSize}/; s/\\/\\* attestation public key size \\*\\//${pubSize}/" Certificates.hpp.template > Certificates.hpp
--- a/IO.cpp
+++ b/IO.cpp
@@ -21,26 +21,24 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 #include <iostream>
 #include <unistd.h>
 //#include <sys/ioctl.h>
-#include <unistd.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <time.h>
-#include <chrono>
-#include <ratio>
-#include "u2f.hpp"
 #include "Macro.hpp"
 #include "U2FDevice.hpp"
+#include "u2f.hpp"
+#include <chrono>
+#include <fcntl.h>
+#include <ratio>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <time.h>
+#include <unistd.h>

 using namespace std;

 bool bytesAvailable(const size_t count);
 vector<uint8_t>& getBuffer();

-vector<uint8_t> readNonBlock(const size_t count)
-{
-	if (!bytesAvailable(count))
-	{
+vector<uint8_t> readNonBlock(const size_t count) {
+	if (!bytesAvailable(count)) {
 		return vector<uint8_t>{};
 	}

@@ -54,32 +52,29 @@ vector<uint8_t> readNonBlock(const size_t count)
 	return bytes;
 }

-void write(const uint8_t* bytes, const size_t count)
-{
+void write(const uint8_t* bytes, const size_t count) {
 	size_t totalBytes = 0;
 	auto hostDescriptor = *getHostDescriptor();

-	while (totalBytes < count)
-	{
+	while (totalBytes < count) {
 		auto writtenBytes = write(hostDescriptor, bytes + totalBytes, count - totalBytes);

 		if (writtenBytes > 0)
 			totalBytes += writtenBytes;
-		else if (errno != 0 && errno != EAGAIN && errno != EWOULDBLOCK) //Expect file blocking behaviour
+		else if (errno != 0 && errno != EAGAIN &&
+		         errno != EWOULDBLOCK) // Expect file blocking behaviour
 			ERR();
 	}

 	errno = 0;
 }

-bool bytesAvailable(const size_t count)
-{
+bool bytesAvailable(const size_t count) {
 	auto startTime = std::chrono::high_resolution_clock::now();
-	const timespec iterDelay{ 0, 1000 };
+	const timespec iterDelay{ 0, 10000000 };
 	chrono::duration<double, milli> delay{ 0 };

-	while (delay.count() < U2FHID_TRANS_TIMEOUT && contProc)
-	{
+	while (delay.count() < U2FHID_TRANS_TIMEOUT && contProc) {
 		delay = chrono::high_resolution_clock::now() - startTime;
 		if (getBuffer().size() >= count) {
 #ifdef DEBUG_MSGS
@@ -97,49 +92,42 @@ bool bytesAvailable(const size_t count)
 	return false;
 }

-vector<uint8_t>& bufferVar()
-{
+vector<uint8_t>& bufferVar() {
 	static vector<uint8_t> buffer{};
 	return buffer;
 }

-vector<uint8_t>& getBuffer()
-{
+vector<uint8_t>& getBuffer() {
 	auto& buff = bufferVar();
 	array<uint8_t, HID_RPT_SIZE> bytes{};
 	auto hostDescriptor = *getHostDescriptor();

-	while (true)
-	{
+	while (true) {
 		auto readByteCount = read(hostDescriptor, bytes.data(), HID_RPT_SIZE);

-		if (readByteCount > 0 && readByteCount != HID_RPT_SIZE)
-		{
+		if (readByteCount > 0 && readByteCount != HID_RPT_SIZE) {
 			// Failed to copy an entire packet in, so log this packet
 #ifdef DEBUG_MSGS
-			cerr << "Only retrieved " << readByteCount << " bytes from expected full packet." << endl;
+			cerr << "Only retrieved " << readByteCount << " bytes from expected full packet."
+			     << endl;
 #endif
 		}

-		if (readByteCount > 0)
-		{
+		if (readByteCount > 0) {
 			copy(bytes.begin(), bytes.begin() + readByteCount, back_inserter(buff));

 #ifdef DEBUG_STREAMS
 			fwrite(bytes.data(), 1, readByteCount, getComHostStream().get());
 #endif

-		}
-		else if (errno != EAGAIN && errno != EWOULDBLOCK) //Expect read would block
+		} else if (errno != EAGAIN && errno != EWOULDBLOCK) // Expect read would block
 		{
 			ERR();
-#if DEBUG_MSGS
+#ifdef DEBUG_MSGS
 			cerr << "Unknown stream error: " << errno << endl;
 #endif
 			break;
-		}
-		else
-		{
+		} else {
 			errno = 0;
 			break; // Escape loop if blocking would occur
 		}
--- a/Keys/certificate.der
+++ b/Keys/certificate.der
--- a/Keys/ecprivkey.pem
+++ b/Keys/ecprivkey.pem
@@ -1,5 +0,0 @@
-----BEGIN EC PRIVATE KEY-----
-MHcCAQEEIH69kQVagJ825S/g0KljDIYEsQTj0fvQg8cuLzS21qSyoAoGCCqGSM49
-AwEHoUQDQgAEMkHDuJaX2JBmQYiW1HO2N/eFKa87FQ+DYWfqybLbgrMsmWCKmHzU
-BKCSIgWq93qRAgPdFYiHaibp7s+ZsWbAAQ==
-----END EC PRIVATE KEY-----
--- a/Keys/ecpubkey.pem
+++ b/Keys/ecpubkey.pem
@@ -1,4 +0,0 @@
-----BEGIN PUBLIC KEY-----
-MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEMkHDuJaX2JBmQYiW1HO2N/eFKa87
-FQ+DYWfqybLbgrMsmWCKmHzUBKCSIgWq93qRAgPdFYiHaibp7s+ZsWbAAQ==
-----END PUBLIC KEY-----
--- a/Keys/privkey.der
+++ b/Keys/privkey.der
@@ -1 +0,0 @@
-~<7E><>Z<><5A>6<EFBFBD>/<2F>Щc<0C><04><04><><EFBFBD>Ѓ<EFBFBD>./4<>֤<EFBFBD>
--- a/Keys/pubkey.der
+++ b/Keys/pubkey.der
@@ -1 +0,0 @@
-2Aø<41><C3B8>ؐfA<66><41><EFBFBD>s<EFBFBD>7<EFBFBD><37>)<29>;<0F>ag<61>ɲۂ<C9B2>,<2C>`<60><>|<7C><04><>"<05><>z<EFBFBD><03><15><>j&<26><>ϙ<EFBFBD>f<EFBFBD>
--- a/Keys/server.pem
+++ b/Keys/server.pem
@@ -1,14 +0,0 @@
-----BEGIN CERTIFICATE-----
-MIICKTCCAdCgAwIBAgIJAIriIT8vi3JSMAoGCCqGSM49BAMCMHAxCzAJBgNVBAYT
-AlVLMRMwEQYDVQQIDApTb21lLVN0YXRlMSEwHwYDVQQKDBhJbnRlcm5ldCBXaWRn
-aXRzIFB0eSBMdGQxKTAnBgNVBAMMIFUyRiBLZXkgdFBGU3FUcW9abWI3OGFqby91
-WFBzUT09MB4XDTE4MDYzMDE5MDc1MVoXDTI4MDYyNzE5MDc1MVowcDELMAkGA1UE
-BhMCVUsxEzARBgNVBAgMClNvbWUtU3RhdGUxITAfBgNVBAoMGEludGVybmV0IFdp
-ZGdpdHMgUHR5IEx0ZDEpMCcGA1UEAwwgVTJGIEtleSB0UEZTcVRxb1ptYjc4YWpv
-L3VYUHNRPT0wWTATBgcqhkjOPQIBBggqhkjOPQMBBwNCAAQyQcO4lpfYkGZBiJbU
-c7Y394UprzsVD4NhZ+rJstuCsyyZYIqYfNQEoJIiBar3epECA90ViIdqJunuz5mx
-ZsABo1MwUTAdBgNVHQ4EFgQUz3/6fcSNumBSTLYWLohix4z84GMwHwYDVR0jBBgw
-FoAUz3/6fcSNumBSTLYWLohix4z84GMwDwYDVR0TAQH/BAUwAwEB/zAKBggqhkjO
-PQQDAgNHADBEAiByJYnBMlRm+A5Yd+O1YkczGFrcKGpKVstYY+OhAmrw2AIgZSaE
-fMM7fWoiDCI9yEO3hIt7SCOwHhM1HRqQRGJsq5s=
-----END CERTIFICATE-----
--- a/LED.cpp
+++ b/LED.cpp
@@ -24,19 +24,16 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.

 using namespace std;

-bool& ledState()
-{
+bool& ledState() {
 	static bool state = true;
 	return state;
 }

-bool getLEDState()
-{
+bool getLEDState() {
 	return ledState();
 }

-void disableACTTrigger([[maybe_unused]] bool nowDisabled)
-{
+void disableACTTrigger([[maybe_unused]] bool nowDisabled) {
 #ifdef LEDS
 	ofstream trigFile{ "/sys/class/leds/led0/trigger", ofstream::out | ofstream::trunc };

@@ -48,8 +45,7 @@ void disableACTTrigger([[maybe_unused]] bool nowDisabled)
 #endif
 }

-void enableACTLED([[maybe_unused]] bool nowOn)
-{
+void enableACTLED([[maybe_unused]] bool nowOn) {
 #ifdef LEDS
 	if (nowOn == getLEDState())
 		return;
@@ -66,7 +62,6 @@ void enableACTLED([[maybe_unused]] bool nowOn)
 #endif
 }

-void toggleACTLED()
-{
+void toggleACTLED() {
 	enableACTLED(!getLEDState());
 }
--- a/Macro.hpp
+++ b/Macro.hpp
@@ -17,7 +17,12 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

 #pragma once
-#include <unistd.h>
 #include <string>
+#include <unistd.h>

-#define ERR() if (errno != 0) perror((string{ "(" } + __FILE__ + ":" + to_string(__LINE__) + ")" + " "  + __PRETTY_FUNCTION__).c_str()), errno = 0
+#define ERR()                                                                                      \
+	if (errno != 0)                                                                                \
+	perror(                                                                                        \
+	    (string{ "(" } + __FILE__ + ":" + to_string(__LINE__) + ")" + " " + __PRETTY_FUNCTION__)   \
+	        .c_str()),                                                                             \
+	    errno = 0
--- a/12
+++ b/12
@@ -1,6 +1,7 @@
 #!/usr/bin/env make

 SRC_DIR  := .
+KEY_DIR  := Keys
 OBJ_DIR  := obj
 CXXFLAGS := -std=c++11 -MMD -MP -Wall -Wfatal-errors -Wextra -fPIE
 LDFLAGS  := -fPIE
@@ -31,7 +32,7 @@ install: U2FDevice
 	install -m775 -t /etc/systemd/system Services/U2FDevice.service
 	install -d /usr/share/U2FDevice/

-$(OBJ_DIR)/%.o: $(SRC_DIR)/%.cpp | $(OBJ_DIR)
+$(OBJ_DIR)/%.o: $(SRC_DIR)/%.cpp | $(OBJ_DIR) $(SRC_DIR)/Certificates.hpp
 	$(CXX) $(STATIC) $(CXXFLAGS) -c -o $@ $<

 $(OBJ_DIR):
@@ -45,7 +46,14 @@ clean:
 	$(MAKE) -C micro-ecc clean
 	$(MAKE) -C cpp-base64 clean

-.PHONY: clean install
+clean-certificates:
+	rm -f $(KEY_DIR)/*
+	rm -f Certificates.cpp Certificates.hpp
+
+$(SRC_DIR)/Certificates.hpp: $(SRC_DIR)/Certificates.hpp.template
+	$(error "Please run the GenCertificates.sh script to generate certificate before building\n")
+
+.PHONY: clean clean-certificates install

 libuECC.a:
 	$(MAKE) -C micro-ecc
--- a/Packet.cpp
+++ b/Packet.cpp
@@ -18,24 +18,22 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.

 #include "Packet.hpp"
 #include "IO.hpp"
+#include "Streams.hpp"
 #include "u2f.hpp"
 #include <cstring>
 #include <iostream>
 #include <unistd.h>
-#include "Streams.hpp"

 using namespace std;

-shared_ptr<InitPacket> InitPacket::getPacket(const uint32_t rCID, const uint8_t rCMD)
-{
+shared_ptr<InitPacket> InitPacket::getPacket(const uint32_t rCID, const uint8_t rCMD) {
 	static size_t bytesRead = 0;
 	static uint8_t bcnth;
 	static uint8_t bcntl;
 	static decltype(InitPacket::data) dataBytes;
 	vector<uint8_t> bytes{};

-	switch (bytesRead)
-	{
+	switch (bytesRead) {
 		case 0:
 			bytes = readNonBlock(1);

@@ -62,7 +60,8 @@ shared_ptr<InitPacket> InitPacket::getPacket(const uint32_t rCID, const uint8_t
 			if (bytes.size() == 0)
 				return {};

-			copy(bytes.begin(), bytes.end(), dataBytes.begin());;
+			copy(bytes.begin(), bytes.end(), dataBytes.begin());
+			;
 			bytesRead += bytes.size();
 			[[fallthrough]];

@@ -82,7 +81,8 @@ shared_ptr<InitPacket> InitPacket::getPacket(const uint32_t rCID, const uint8_t

 #ifdef DEBUG_STREAMS
 	auto hPStream = getHostPacketStream().get();
-	fprintf(hPStream, "\t\t<table>\n"
+	fprintf(hPStream,
+	        "\t\t<table>\n"
 	        "\t\t\t<thead>\n"
 	        "\t\t\t\t<tr>\n"
 	        "\t\t\t\t\t<th>CID</th>\n"
@@ -98,7 +98,8 @@ shared_ptr<InitPacket> InitPacket::getPacket(const uint32_t rCID, const uint8_t
 	        "\t\t\t\t\t<td>%u</td>\n"
 	        "\t\t\t\t\t<td>%u</td>\n"
 	        "\t\t\t\t\t<td>%u</td>\n"
-			"\t\t\t\t\t<td class=\"data\">", p->cid, p->cmd, p->bcnth, p->bcntl);
+	        "\t\t\t\t\t<td class=\"data\">",
+	        p->cid, p->cmd, p->bcnth, p->bcntl);

 	for (auto elem : dataBytes)
 		fprintf(hPStream, "%3u ", elem);
@@ -114,16 +115,14 @@ shared_ptr<InitPacket> InitPacket::getPacket(const uint32_t rCID, const uint8_t
 	return p;
 }

-shared_ptr<ContPacket> ContPacket::getPacket(const uint32_t rCID, const uint8_t rSeq)
-{
+shared_ptr<ContPacket> ContPacket::getPacket(const uint32_t rCID, const uint8_t rSeq) {
 	static size_t readBytes = 0;
 	static decltype(ContPacket::data) dataBytes;

 	vector<uint8_t> bytes{};
 	auto p = make_shared<ContPacket>();

-	if (readBytes != dataBytes.size())
-	{
+	if (readBytes != dataBytes.size()) {
 		dataBytes = {};
 		bytes = readNonBlock(dataBytes.size());

@@ -140,7 +139,8 @@ shared_ptr<ContPacket> ContPacket::getPacket(const uint32_t rCID, const uint8_t

 #ifdef DEBUG_STREAMS
 	auto hPStream = getHostPacketStream().get();
-	fprintf(hPStream, "\t\t<table>\n"
+	fprintf(hPStream,
+	        "\t\t<table>\n"
 	        "\t\t\t<thead>\n"
 	        "\t\t\t\t<tr>\n"
 	        "\t\t\t\t\t<th>CID</th>\n"
@@ -152,7 +152,8 @@ shared_ptr<ContPacket> ContPacket::getPacket(const uint32_t rCID, const uint8_t
 	        "\t\t\t\t<tr>\n"
 	        "\t\t\t\t\t<td>0x%08X</td>\n"
 	        "\t\t\t\t\t<td>%u</td>\n"
-			"\t\t\t\t\t<td class=\"data\">", p->cid, p->seq);
+	        "\t\t\t\t\t<td class=\"data\">",
+	        p->cid, p->seq);

 	for (auto elem : dataBytes)
 		fprintf(hPStream, "%3u ", elem);
@@ -168,8 +169,7 @@ shared_ptr<ContPacket> ContPacket::getPacket(const uint32_t rCID, const uint8_t
 	return p;
 }

-shared_ptr<Packet> Packet::getPacket()
-{
+shared_ptr<Packet> Packet::getPacket() {
 	static size_t bytesRead = 0;
 	vector<uint8_t> bytes{};

@@ -177,8 +177,7 @@ shared_ptr<Packet> Packet::getPacket()
 	static uint8_t b;
 	shared_ptr<Packet> packet{};

-	switch (bytesRead)
-	{
+	switch (bytesRead) {
 		case 0:
 			bytes = readNonBlock(4);

@@ -200,8 +199,7 @@ shared_ptr<Packet> Packet::getPacket()
 			[[fallthrough]];

 		case 5:
-			if (b & TYPE_MASK)
-			{
+			if (b & TYPE_MASK) {
 				// Init packet
 				packet = InitPacket::getPacket(cid, b);

@@ -209,9 +207,7 @@ shared_ptr<Packet> Packet::getPacket()
 					bytesRead = 0;

 				return packet;
-			}
-			else
-			{
+			} else {
 				// Cont packet
 				packet = ContPacket::getPacket(cid, b);

@@ -225,14 +221,12 @@ shared_ptr<Packet> Packet::getPacket()
 	}
 }

-void Packet::writePacket()
-{
+void Packet::writePacket() {
 	memset(this->buf, 0, HID_RPT_SIZE);
 	memcpy(this->buf, &cid, 4);
 }

-void InitPacket::writePacket()
-{
+void InitPacket::writePacket() {
 	Packet::writePacket();

 #ifdef DEBUG_STREAMS
@@ -249,7 +243,8 @@ void InitPacket::writePacket()
 	fwrite(this->buf, 1, sizeof(this->buf), devStream);

 	auto dPStream = getDevPacketStream().get();
-	fprintf(dPStream, "\t\t<table>\n"
+	fprintf(dPStream,
+	        "\t\t<table>\n"
 	        "\t\t\t<thead>\n"
 	        "\t\t\t\t<tr>\n"
 	        "\t\t\t\t\t<th>CID</th>\n"
@@ -265,7 +260,8 @@ void InitPacket::writePacket()
 	        "\t\t\t\t\t<td>%u</td>\n"
 	        "\t\t\t\t\t<td>%u</td>\n"
 	        "\t\t\t\t\t<td>%u</td>\n"
-			"\t\t\t\t\t<td class=\"data\">", cid, cmd, bcnth, bcntl);
+	        "\t\t\t\t\t<td class=\"data\">",
+	        cid, cmd, bcnth, bcntl);

 	for (auto elem : data)
 		fprintf(dPStream, "%3u ", elem);
@@ -278,8 +274,7 @@ void InitPacket::writePacket()
 #endif
 }

-void ContPacket::writePacket()
-{
+void ContPacket::writePacket() {
 	Packet::writePacket();

 #ifdef DEBUG_STREAMS
@@ -295,7 +290,8 @@ void ContPacket::writePacket()

 	auto dPStream = getDevPacketStream().get();

-	fprintf(dPStream, "\t\t<table>\n"
+	fprintf(dPStream,
+	        "\t\t<table>\n"
 	        "\t\t\t<thead>\n"
 	        "\t\t\t\t<tr>\n"
 	        "\t\t\t\t\t<th>CID</th>\n"
@@ -307,7 +303,8 @@ void ContPacket::writePacket()
 	        "\t\t\t\t<tr>\n"
 	        "\t\t\t\t\t<td>0x%08X</td>\n"
 	        "\t\t\t\t\t<td>%u</td>\n"
-			"\t\t\t\t\t<td class=\"data\">", cid, seq);
+	        "\t\t\t\t\t<td class=\"data\">",
+	        cid, seq);

 	for (auto elem : data)
 		fprintf(dPStream, "%3u ", elem);
--- a/Packet.hpp
+++ b/Packet.hpp
@@ -17,13 +17,12 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

 #pragma once
+#include "u2f.hpp"
+#include <array>
 #include <cstdint>
 #include <memory>
-#include <array>
-#include "u2f.hpp"

-struct Packet
-{
+struct Packet {
 public:
 	uint32_t cid;
 	uint8_t buf[HID_RPT_SIZE];
@@ -37,8 +36,7 @@ struct Packet
 	virtual ~Packet() = default;
 };

-struct InitPacket : Packet
-{
+struct InitPacket : Packet {
 public:
 	uint8_t cmd;
 	uint8_t bcnth;
@@ -51,8 +49,7 @@ struct InitPacket : Packet
 	void writePacket() override;
 };

-struct ContPacket : Packet
-{
+struct ContPacket : Packet {
 public:
 	uint8_t seq;
 	std::array<uint8_t, HID_RPT_SIZE - 5> data{};
--- a/Readme.AttestationCertificateGeneration.md
+++ b/Readme.AttestationCertificateGeneration.md
@@ -0,0 +1,67 @@
+# Automatically generate keys
+
+Run `./GenCertificates.sh`, answering the prompt to produce your own certificate.
+
+# Manually generate keys
+
+From [Teensy U2F](https://github.com/pratikd650/Teensy_U2F/blob/master/Teensy_U2F.cpp) line 292
+
+Instructions to generate attestation certificate using open ssl
+[OpenSSL wiki](https://wiki.openssl.org/index.php/Command_Line_Elliptic_Curve_Operations)
+[Guy Rutenberg](https://www.guyrutenberg.com/2013/12/28/creating-self-signed-ecdsa-ssl-certificate-using-openssl/)
+ P-256 (also secp256r1)  EC key pair is    W = dG   (Note secp256k1 is Koblitz curve - not P256)
+ d = private key is it 256 bits (32 bytes)
+ G = generator point - it is part of the curve definition
+ W = public key point - it is a (256, 256) bits  - 64 bytes
+
+1) Generate a key pair - the private key will be saved in PKCS8 format in ecprivkey.pem
+
+`openssl ecparam -name prime256v1 -genkey -noout -out ecprivkey.pem`
+
+2) Dump out the private key in hex format - it will be a 32 byte key
+
+`openssl asn1parse -in ecprivkey.pem`
+
+3) Compute the public key from the private key and the curve
+
+`openssl ec -in ecprivkey.pem -pubout -out ecpubkey.pem`
+
+4) Dump out the public key in hex format - it will be 66 byte - the first two bytes are 00 04,
+
+`openssl ec -in ecprivkey.pem -pubout -text`
+
+after that is the point W - 32 byte + 32 byte
+
+5) Generate a self signed certificate
+
+`openssl req -new -x509 -key ecprivkey.pem -out certificate.pem -days 3650`
+
+For the Certificate name give a unique certificate name.
+
+6) Display the certificate
+
+`openssl x509 -in certificate.pem -text -noout`
+
+7) Convert PEM certificate to DER
+
+`openssl x509 -outform der -in certificate.pem -out certificate.der`
+
+8) Generate a usable c-array for source code
+
+`xxd --include certificate.der | sed -e '0,/{/d;/};/,$d'`
+
+Copy output into appropriate array in 'Certificates.cpp', overwriting existing values
+
+9) Find the public key
+
+`openssl ec -in ecprivkey.pem -pubout -text -noout 2>/dev/null | sed -e '0,/priv:/d;/pub:/,$d' -e 's/\s//g;s/:/, /g' -e 's/^/\t/g;s/\s\+$//g' -e 's/\(\s\)/\10x/g'`
+
+10) Find the private key
+
+`openssl ec -in ecprivkey.pem -pubout -text -noout 2>/dev/null | sed -e '0,/pub:/d;/ASN1/,$d' | sed -e 's/\s//g;s/:/, /g' -e 's/^/\t/g;s/\s\+$//g' -e 's/\(\s\)/\10x/g'`
+
+11)
+
+Copy the arrays into the correct arrays in Certificates.cpp.
+
+If any arrays have different lengths than shown in Certificates.hpp, update these too.
--- a/Readme.AttestationCertificateGeneration.txt
+++ b/Readme.AttestationCertificateGeneration.txt
@@ -1,45 +0,0 @@
-From https://github.com/pratikd650/Teensy_U2F/blob/master/Teensy_U2F.cpp line 292
-
-Instructions to generate attestation certificate using open ssl
-https://wiki.openssl.org/index.php/Command_Line_Elliptic_Curve_Operations
-https://www.guyrutenberg.com/2013/12/28/creating-self-signed-ecdsa-ssl-certificate-using-openssl/
- P-256 (also secp256r1)  EC key pair is    W = dG   (Note secp256k1 is Koblitz curve - not P256)
- d = private key is it 256 bits (32 bytes)
- G = generator point - it is part of the curve definition
- W = public key point - it is a (256, 256) bits  - 64 bytes
-1) generate a key pair - the private key will be saved in PKCS8 format in ecprivkey.pem
-openssl ecparam -name prime256v1 -genkey -noout -out ecprivkey.pem
-2) dump out the private key in hex format - it will be a 32 byte key
- openssl asn1parse  -in ecprivkey.pem
-3) compute the public key from the private key and the curve
-openssl ec -in ecprivkey.pem -pubout -out ecpubkey.pem
-4) dump out the public key in hex format - it will be 66 byte - the first two bytes are 00 04,
-  openssl ec -in ecprivkey.pem -pubout -text
-  after that is the point W - 32 byte + 32 byte
-5) generate a self signed certificate
-  openssl req -new -x509 -key ecprivkey.pem -out server.pem -days 3650
-For the Certificate name give a unique certificate name. There is a 128 bit unique identification number burned into every
-Teensy chip  - see http://cache.freescale.com/files/32bit/doc/data_sheet/K20P64M72SF1.pdf
-You can print out the number from your Teensy using this simple program given below
-6) Display the certificate
-  openssl x509 -in server.pem -text -noout
-
-7) Convert PEM certificate to DER
-openssl x509 -outform der -in server.pem -out certificate.der
-
-8) Generate a usable c-array for source code
-xxd --include certificate.pem
-
-Copy output into appropriate array in 'Certificates.cpp', overwriting existing values
-
-9) Repeat steps 7 & 8 for public key and private key
-
-So:
-`
-openssl asn1parse -in ecprivkey.pem 2>/dev/null | grep 'HEX DUMP' | perl -pe 's/^.*\[HEX DUMP\]:(.+)$/$1/' 2>/dev/null | xxd -r -p > privkey.der && xxd --include privkey.der
-
-openssl ec -in ecprivkey.pem -pubout -text 2>/dev/null | perl -0777 -ne 'print /pub:.+ASN1/sg' 2>/dev/null | sed -e '/pub:/d;/ASN1/d' | perl -pe 's/^\s+(.+):?$/$1/gm' 2>/dev/null | perl -pe 's/\n//' 2>/dev/null | perl -pe 's/(.{2}):?/$1/g' 2>/dev/null | xxd -r -p > pubkey.der && xxd --include pubkey.der
-`
-and copy the arrays into the correct arrays in Certificates.cpp
-
-If any arrays have different lengths than shown in Certificates.hpp, update these too.
--- a/Readme.md
+++ b/Readme.md
@@ -1,5 +1,7 @@
 # U2FDevice

+For the Android version of this, please see [the android branch](../../tree/android), as there is a completely different build procedure and resources.
+
 This program uses a Raspberry Pi 0 to act as a [U2F token](https://www.yubico.com/solutions/fido-u2f/). This permits any person with a Raspberry Pi 0 to try out U2F 2FA for themselves.

 # Required materials
@@ -209,6 +211,12 @@ Then, reload the rules using `sudo udevadm control --reload-rules `
 4. Make the object file directories using `mkdir obj && mkdir cpp-base64/obj && mkdir micro-ecc/obj`
 5. Grab the required library using `sudo apt-get install libmbedtls-dev`

+## Generate a certificate
+
+If you wish to do this automatically, just run `./GenCertificates.sh`, and answer the prompt with as much detail as you feel like entrusting to websites.
+
+Alternatively, see `Readme.AttestationCertifcateGeneration.md` for a much more manual approach.
+
 ## Build the program

 1. Run `make`
@@ -241,11 +249,15 @@ For these reasons, if you want to use this as a way to backup your other U2F dev

 1. Install `rng-tools` with `sudo apt-get install rng-tools`

-## To change the Attestation certificate
+## Notes about a custom attestation certificate

-This may be highly advisable, or inadvisable - I am currently unsure. <br />All registration requests use this private key, so likely advisable. <br/>However, you can be uniquely identified by having a unique attestation certificate.
+By using a custom attestation certificate, you lose the anonymity of conventional u2f keys. This is because they are produced in large batches and thus can share a single certificate, burned into some private ROM. However, since you require the private key to sign, and this repo is public, it is impossible to use a single signature for everyone who uses this repository.

-See the `Readme.AttestationCertificateGeneration.txt`
+However, by generating your own certificate, you can be more assured about the inherent security of your certificate (no-one can leak the private key but you).
+
+Note, however, that this key and certificate is only used for registration - not for further authentication.
+
+See the `Readme.AttestationCertificateGeneration.md`

 # Running the program

@@ -261,7 +273,7 @@ If the program doesn't work on these - don't use as a backup device.

 Once the program runs successfully, you can enable automatic startup at boot.

-Run `sudo systmectl enable U2FDevice.service`
+Run `sudo systemctl enable U2FDevice.service`

 ## Debug files

--- a/Signature.cpp
+++ b/Signature.cpp
@@ -22,21 +22,18 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 using namespace std;

 // Ripped from https://github.com/pratikd650/Teensy_U2F/blob/master/Teensy_U2F.cpp
-void appendSignatureAsDER(vector<uint8_t> &response, const array<uint8_t, 64> &signature)
-{
+void appendSignatureAsDER(vector<uint8_t>& response, const array<uint8_t, 64>& signature) {
 	response.push_back(0x30); // Start of ASN.1 SEQUENCE
 	response.push_back(68);   // total length from (2 * (32 + 2)) to (2 * (33 + 2))
 	size_t countByte = response.size() - 1;

 	// Loop twice - for R and S
-	for(unsigned int i = 0; i < 2; i++)
-	{
+	for (unsigned int i = 0; i < 2; i++) {
 		unsigned int sigOffs = i * 32;
 		auto offset = signature.begin() + sigOffs;
 		response.push_back(0x02); // header: integer
 		response.push_back(32);   // 32 byte
-		if (signature[sigOffs] > 0x7f)
-		{
+		if (signature[sigOffs] > 0x7f) {
 			// Integer needs to be represented in 2's completement notion
 			response.back()++;
 			response.push_back(0); // add leading 0, to indicate it is a positive number
--- a/Signature.hpp
+++ b/Signature.hpp
@@ -17,8 +17,8 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

 #pragma once
-#include <vector>
 #include <array>
+#include <vector>

 using Digest = std::array<uint8_t, 32>;
 using Signature = std::array<uint8_t, 64>;
--- a/Storage.cpp
+++ b/Storage.cpp
@@ -17,10 +17,10 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

 #include "Storage.hpp"
-#include <exception>
-#include <sstream>
 #include "Base64.tpp"
+#include <exception>
 #include <iostream>
+#include <sstream>

 using namespace std;

@@ -30,15 +30,13 @@ std::map<Storage::KeyHandle, Storage::PrivKey>  Storage::privKeys{};
 std::map<Storage::KeyHandle, Storage::PubKey> Storage::pubKeys{};
 std::map<Storage::KeyHandle, Storage::KeyCount> Storage::keyCounts{};

-void Storage::init(const string &dirPrefix)
-{
+void Storage::init(const string& dirPrefix) {
 	Storage::filename = dirPrefix + "U2F_Priv_Keys.txt";
 	ifstream file{ Storage::filename };
 	string line;
 	size_t lineNumber = 0;

-	while (getline(file, line))
-	{
+	while (getline(file, line)) {
 		auto strLineNum = to_string(lineNumber);
 		stringstream ss{ line };
 		string keyHStr, appStr, privStr, pubStr, keyCStr;
@@ -48,13 +46,15 @@ void Storage::init(const string &dirPrefix)
 			throw runtime_error{ string{ "Invalid syntax of line " } + strLineNum };

 		char* endP = nullptr;
-		Storage::KeyHandle keyH{ static_cast<Storage::KeyHandle>(strtoull(keyHStr.c_str(), &endP, 10)) };
+		Storage::KeyHandle keyH{ static_cast<Storage::KeyHandle>(
+			strtoull(keyHStr.c_str(), &endP, 10)) };

 		if (!endP)
 			throw runtime_error{ "Invalid keyhandle format on line " + strLineNum };

 		endP = nullptr;
-		Storage::KeyCount keyC{ static_cast<Storage::KeyCount>(strtoull(keyCStr.c_str(), &endP, 10)) };
+		Storage::KeyCount keyC{ static_cast<Storage::KeyCount>(
+			strtoull(keyCStr.c_str(), &endP, 10)) };

 		if (!endP)
 			throw runtime_error{ "Invalid key count format on line " + strLineNum };
@@ -77,12 +77,10 @@ void Storage::init(const string &dirPrefix)
 	}
 }

-void Storage::save()
-{
+void Storage::save() {
 	ofstream file{ Storage::filename };

-	for (auto &keypair : Storage::appParams)
-	{
+	for (const auto& keypair : Storage::appParams) {
 		const auto& keyID = keypair.first;
 		const auto& appParam = keypair.second;
 		const auto& privKey = Storage::privKeys[keyID];
--- a/Storage.hpp
+++ b/Storage.hpp
@@ -17,13 +17,12 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

 #pragma once
-#include <map>
 #include <array>
-#include <string>
 #include <fstream>
+#include <map>
+#include <string>

-class Storage
-{
+class Storage {
 public:
 	using KeyHandle = uint32_t;
 	using KeyCount = uint32_t;
--- a/Streams.cpp
+++ b/Streams.cpp
@@ -17,11 +17,11 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

 #include "Streams.hpp"
-#include <iostream>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
 #include <cstdio>
+#include <fcntl.h>
+#include <iostream>
+#include <sys/stat.h>
+#include <sys/types.h>
 #include <unistd.h>

 using namespace std;
@@ -31,14 +31,12 @@ FILE* initHTML(FILE *fPtr, const string &title);
 void closeHTML(FILE* fPtr);
 #endif

-shared_ptr<int> getHostDescriptor()
-{
-	static shared_ptr<int> descriptor{};
-	
-	descriptor.reset(new int{ open(HID_DEV, O_RDWR | O_NONBLOCK | O_APPEND) }, [](int* fd){
+shared_ptr<int> getHostDescriptor() {
+	static shared_ptr<int> descriptor{ new int{ open(HID_DEV, O_RDWR | O_NONBLOCK | O_APPEND) },
+		                               [](int* fd) {
 		                                   close(*fd);
 		                                   delete fd;
-	});
+		                               } };

 	if (*descriptor == -1)
 		throw runtime_error{ "Descriptor is unavailable" };
@@ -47,8 +45,7 @@ shared_ptr<int> getHostDescriptor()
 }

 #ifdef DEBUG_STREAMS
-shared_ptr<FILE> getComHostStream()
-{
+shared_ptr<FILE> getComHostStream() {
 	static shared_ptr<FILE> stream{ fopen(DEBUG_STREAMS "comhost.txt", "wb"), [](FILE* f) {
 		                               clog << "Closing comhost stream" << endl;
 		                               fclose(f);
@@ -60,9 +57,10 @@ shared_ptr<FILE> getComHostStream()
 	return stream;
 }

-shared_ptr<FILE> getHostPacketStream()
-{
-	static shared_ptr<FILE> stream{ initHTML(fopen(DEBUG_STREAMS "hostpackets.html", "wb"), "Host Packets"), [](FILE *f){
+shared_ptr<FILE> getHostPacketStream() {
+	static shared_ptr<FILE> stream{ initHTML(fopen(DEBUG_STREAMS "hostpackets.html", "wb"),
+		                                     "Host Packets"),
+		                            [](FILE* f) {
 		                                clog << "Closing hostPackets stream" << endl;
 		                                closeHTML(f);
 		                            } };
@@ -73,9 +71,10 @@ shared_ptr<FILE> getHostPacketStream()
 	return stream;
 }

-shared_ptr<FILE> getHostAPDUStream()
-{
-	static shared_ptr<FILE> stream{ initHTML(fopen(DEBUG_STREAMS "hostAPDU.html", "wb"), "Host APDU"), [](FILE *f){
+shared_ptr<FILE> getHostAPDUStream() {
+	static shared_ptr<FILE> stream{ initHTML(fopen(DEBUG_STREAMS "hostAPDU.html", "wb"),
+		                                     "Host APDU"),
+		                            [](FILE* f) {
 		                                clog << "Closing host APDU stream" << endl;
 		                                closeHTML(f);
 		                            } };
@@ -86,8 +85,7 @@ shared_ptr<FILE> getHostAPDUStream()
 	return stream;
 }

-shared_ptr<FILE> getComDevStream()
-{
+shared_ptr<FILE> getComDevStream() {
 	static shared_ptr<FILE> stream{ fopen(DEBUG_STREAMS "comdev.txt", "wb"), [](FILE* f) {
 		                               clog << "Closing comdev stream" << endl;
 		                               fclose(f);
@@ -99,9 +97,10 @@ shared_ptr<FILE> getComDevStream()
 	return stream;
 }

-shared_ptr<FILE> getDevPacketStream()
-{
-	static shared_ptr<FILE> stream{ initHTML(fopen(DEBUG_STREAMS "devpackets.html", "wb"), "Dev Packets"), [](FILE *f){
+shared_ptr<FILE> getDevPacketStream() {
+	static shared_ptr<FILE> stream{ initHTML(fopen(DEBUG_STREAMS "devpackets.html", "wb"),
+		                                     "Dev Packets"),
+		                            [](FILE* f) {
 		                                clog << "Closing devPackets stream" << endl;
 		                                closeHTML(f);
 		                            } };
@@ -112,9 +111,9 @@ shared_ptr<FILE> getDevPacketStream()
 	return stream;
 }

-shared_ptr<FILE> getDevAPDUStream()
-{
-	static shared_ptr<FILE> stream{ initHTML(fopen(DEBUG_STREAMS "devAPDU.html", "wb"), "Dev APDU"), [](FILE *f){
+shared_ptr<FILE> getDevAPDUStream() {
+	static shared_ptr<FILE> stream{ initHTML(fopen(DEBUG_STREAMS "devAPDU.html", "wb"), "Dev APDU"),
+		                            [](FILE* f) {
 		                                clog << "Closing dev APDU stream" << endl;
 		                                closeHTML(f);
 		                            } };
@@ -125,9 +124,9 @@ shared_ptr<FILE> getDevAPDUStream()
 	return stream;
 }

-FILE* initHTML(FILE *fPtr, const string &title)
-{
-	fprintf(fPtr, "<html>\n"
+FILE* initHTML(FILE* fPtr, const string& title) {
+	fprintf(fPtr,
+	        "<html>\n"
 	        "\t<head>\n"
 	        "\t\t<title>%s</title>\n"
 	        "\t\t<style>\n"
@@ -164,15 +163,18 @@ FILE* initHTML(FILE *fPtr, const string &title)
 	        "\t\t</style>\n"
 	        "\t</head>\n"
 	        "\n"
-				"\t<body>", title.c_str());
+	        "\t<body>",
+	        title.c_str());

 	return fPtr;
 }

-void closeHTML(FILE *fPtr)
-{
+void closeHTML(FILE* fPtr) {
 	fprintf(fPtr, "\t</body>\n"
 	              "</html>");
-	fclose(fPtr);
+	int successCode = fclose(fPtr);
+
+	if (successCode != 0)
+		cerr << "File closing error: " << errno << endl;
 }
 #endif
--- a/Streams.hpp
+++ b/Streams.hpp
@@ -17,9 +17,9 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

 #pragma once
+#include "Architecture.hpp"
 #include <cstdio>
 #include <memory>
-#include "Architecture.hpp"

 std::shared_ptr<int> getHostDescriptor();

--- a/U2FDevice.cpp
+++ b/U2FDevice.cpp
@@ -17,10 +17,10 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

 #include "Architecture.hpp"
-#include <iostream>
-#include "Storage.hpp"
 #include "Controller.hpp"
 #include "LED.hpp"
+#include "Storage.hpp"
+#include <iostream>
 #include <signal.h>
 #include <unistd.h>

@@ -31,13 +31,10 @@ void signalCallback(int signum);
 volatile bool contProc = true;

 bool initialiseLights(const string& prog) {
-	try
-	{
+	try {
 		disableACTTrigger(true);
 		enableACTLED(false);
-	}
-	catch (runtime_error &e)
-	{
+	} catch (runtime_error& e) {
 		cerr << e.what() << endl;

 		if (getuid() != 0)
@@ -49,20 +46,16 @@ bool initialiseLights(const string& prog) {
 	return true;
 }

-int handleTransactions(const string& prog, const string& privKeyDir)
-{
+int handleTransactions(const string& prog, const string& privKeyDir) {
 	signal(SIGINT, signalCallback);
+	signal(SIGTERM, signalCallback);
 	Storage::init(privKeyDir);
 	Controller ch{ 0xF1D00000 };

-	while (contProc)
-	{
-		try
-		{
+	while (contProc) {
+		try {
 			ch.handleTransaction();
-		}
-		catch (const runtime_error &e)
-		{
+		} catch (const runtime_error& e) {
 			cerr << e.what() << endl;

 			if (getuid() != 0)
@@ -79,13 +72,10 @@ int handleTransactions(const string& prog, const string& privKeyDir)
 }

 bool deinitialiseLights(const string& prog) {
-	try
-	{
+	try {
 		disableACTTrigger(false);
 		enableACTLED(true);
-	}
-	catch (runtime_error &e)
-	{
+	} catch (runtime_error& e) {
 		cerr << e.what() << endl;

 		if (getuid() != 0)
@@ -97,8 +87,7 @@ bool deinitialiseLights(const string& prog) {
 	return true;
 }

-void signalCallback([[maybe_unused]] int signum)
-{
+void signalCallback([[maybe_unused]] int signum) {
 	contProc = false;
 	clog << "\nClosing" << endl;
 }
--- a/U2FDevice.hpp
+++ b/U2FDevice.hpp
@@ -24,4 +24,3 @@ extern volatile bool contProc;
 bool initialiseLights(const std::string& prog);
 bool deinitialiseLights(const std::string& prog);
 int handleTransactions(const std::string& prog, const std::string& privKeyDir);
-
--- a/U2FMessage.cpp
+++ b/U2FMessage.cpp
@@ -17,18 +17,17 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

 #include "U2FMessage.hpp"
+#include "IO.hpp"
 #include "Packet.hpp"
-#include <stdexcept>
-#include <iostream>
-#include <iomanip>
 #include "Streams.hpp"
 #include "u2f.hpp"
-#include "IO.hpp"
+#include <iomanip>
+#include <iostream>
+#include <stdexcept>

 using namespace std;

-shared_ptr<U2FMessage> U2FMessage::readNonBlock()
-{
+shared_ptr<U2FMessage> U2FMessage::readNonBlock() {
 	const static size_t startSeq = (size_t)-1ull;
 	static size_t currSeq = startSeq;
 	static uint16_t messageSize;
@@ -38,16 +37,14 @@ shared_ptr<U2FMessage> U2FMessage::readNonBlock()

 	shared_ptr<Packet> p{};

-	if (currSeq == startSeq)
-	{
+	if (currSeq == startSeq) {
 		cid = 0;
 		cmd = 0;
 		messageSize = 0;
 		dataBytes = {};

 		shared_ptr<InitPacket> initPack{};
-		do
-		{
+		do {
 			p = Packet::getPacket();

 			if (!p)
@@ -62,16 +59,19 @@ shared_ptr<U2FMessage> U2FMessage::readNonBlock()
 		} while (!initPack); // Spurious cont. packet - spec states ignore

 		messageSize = ((static_cast<uint16_t>(initPack->bcnth) << 8u) + initPack->bcntl);
-		const uint16_t copyByteCount = min(static_cast<uint16_t>(initPack->data.size()), messageSize);
+		const uint16_t copyByteCount =
+		    min(static_cast<uint16_t>(initPack->data.size()), messageSize);

 		cid = initPack->cid;
 		cmd = initPack->cmd;

-		copy(initPack->data.begin(), initPack->data.begin() + copyByteCount, back_inserter(dataBytes));
+		copy(initPack->data.begin(), initPack->data.begin() + copyByteCount,
+		     back_inserter(dataBytes));
 		currSeq = 0;
 	}

-	while (messageSize > dataBytes.size() && static_cast<bool>(p = Packet::getPacket())) //While there is a packet
+	while (messageSize > dataBytes.size() &&
+	       static_cast<bool>(p = Packet::getPacket())) // While there is a packet
 	{
 		auto contPack = dynamic_pointer_cast<ContPacket>(p);

@@ -87,15 +87,15 @@ shared_ptr<U2FMessage> U2FMessage::readNonBlock()
 		if (contPack->cid != cid) // Cont. packet of different CID
 		{
 #ifdef DEBUG_MSGS
-			cerr << "Invalid CID: was handling channel 0x" << hex << cid << " and received packet from channel 0x" << contPack->cid << dec << endl;
+			cerr << "Invalid CID: was handling channel 0x" << hex << cid
+			     << " and received packet from channel 0x" << contPack->cid << dec << endl;
 #endif
 			U2FMessage::error(contPack->cid, ERR_CHANNEL_BUSY);
 			currSeq = startSeq;
 			return {};
 		}

-		if (contPack->seq != currSeq)
-		{
+		if (contPack->seq != currSeq) {
 #ifdef DEBUG_MSGS
 			cerr << "Invalid packet seq. value" << endl;
 #endif
@@ -105,15 +105,18 @@ shared_ptr<U2FMessage> U2FMessage::readNonBlock()
 		}

 		const uint16_t remainingBytes = messageSize - dataBytes.size();
-		const uint16_t copyBytes = min(static_cast<uint16_t>(contPack->data.size()), remainingBytes);
+		const uint16_t copyBytes =
+		    min(static_cast<uint16_t>(contPack->data.size()), remainingBytes);

-		dataBytes.insert(dataBytes.end(), contPack->data.begin(), contPack->data.begin() + copyBytes);
+		dataBytes.insert(dataBytes.end(), contPack->data.begin(),
+		                 contPack->data.begin() + copyBytes);
 		currSeq++;
 	}

 	if (messageSize != dataBytes.size()) {
 #ifdef DEBUG_MSGS
-		cerr << "Invalid message size: " << messageSize << " when received " << dataBytes.size() << endl;
+		cerr << "Invalid message size: " << messageSize << " when received " << dataBytes.size()
+		     << endl;
 #endif
 		return {};
 	}
@@ -125,8 +128,7 @@ shared_ptr<U2FMessage> U2FMessage::readNonBlock()
 	return message;
 }

-void U2FMessage::write()
-{
+void U2FMessage::write() {
 	const uint16_t bytesToWrite = this->data.size();
 	uint16_t bytesWritten = 0;

@@ -141,7 +143,8 @@ void U2FMessage::write()
 		p.bcntl = bcntl;

 		{
-			uint16_t initialByteCount = min(static_cast<uint16_t>(p.data.size()), static_cast<uint16_t>(bytesToWrite - bytesWritten));
+			uint16_t initialByteCount = min(static_cast<uint16_t>(p.data.size()),
+			                                static_cast<uint16_t>(bytesToWrite - bytesWritten));
 			copy(data.begin(), data.begin() + initialByteCount, p.data.begin());
 			bytesWritten += initialByteCount;
 		}
@@ -151,20 +154,20 @@ void U2FMessage::write()

 	uint8_t seq = 0;

-	while (bytesWritten != bytesToWrite)
-	{
+	while (bytesWritten != bytesToWrite) {
 		ContPacket p{};
 		p.cid = cid;
 		p.seq = seq;
-		uint16_t newByteCount = min(static_cast<uint16_t>(p.data.size()), static_cast<uint16_t>(bytesToWrite - bytesWritten));
-		copy(data.begin() + bytesWritten, data.begin() + bytesWritten + newByteCount, p.data.begin());
+		uint16_t newByteCount = min(static_cast<uint16_t>(p.data.size()),
+		                            static_cast<uint16_t>(bytesToWrite - bytesWritten));
+		copy(data.begin() + bytesWritten, data.begin() + bytesWritten + newByteCount,
+		     p.data.begin());
 		p.writePacket();
 		seq++;
 		bytesWritten += newByteCount;
 	}

-	if (cmd == U2FHID_MSG)
-	{
+	if (cmd == U2FHID_MSG) {
 #ifdef DEBUG_STREAMS
 		auto dAS = getDevAPDUStream().get();

@@ -187,22 +190,21 @@ void U2FMessage::write()
 		err |= data.back();

 #ifdef DEBUG_STREAMS
-		fprintf(dAS, "</td>\n"
+		fprintf(dAS,
+		        "</td>\n"
 		        "\t\t\t\t\t<td>0x%04X</td>\n"
 		        "\t\t\t\t</tr>\n"
 		        "\t\t\t</tbody>\n"
 		        "\t\t</table>\n"
-				"\t\t<br />", err);
+		        "\t\t<br />",
+		        err);
 #endif
 	}
 }

-U2FMessage::U2FMessage(const uint32_t nCID, const uint8_t nCMD)
-	: cid{ nCID }, cmd{ nCMD }
-{}
+U2FMessage::U2FMessage(const uint32_t nCID, const uint8_t nCMD) : cid{ nCID }, cmd{ nCMD } {}

-void U2FMessage::error(const uint32_t tCID, const uint8_t tErr)
-{
+void U2FMessage::error(const uint32_t tCID, const uint8_t tErr) {
 	U2FMessage msg{};
 	msg.cid = tCID;
 	msg.cmd = U2FHID_ERROR;
--- a/U2FMessage.hpp
+++ b/U2FMessage.hpp
@@ -18,13 +18,10 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.

 #pragma once
 #include <cstdint>
-#include <vector>
 #include <memory>
-#include <cstdint>
+#include <vector>

-struct U2FMessage
-{
-	public:
+struct U2FMessage {
 	uint32_t cid;
 	uint8_t cmd;
 	std::vector<uint8_t> data;
--- a/U2F_Authenticate_APDU.cpp
+++ b/U2F_Authenticate_APDU.cpp
@@ -17,28 +17,24 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

 #include "U2F_Authenticate_APDU.hpp"
-#include "Field.hpp"
-#include "U2FMessage.hpp"
-#include "u2f.hpp"
-#include "Field.tpp"
 #include "APDU.hpp"
-#include <iostream>
+#include "Field.hpp"
+#include "Field.tpp"
 #include "Signature.hpp"
+#include "U2FMessage.hpp"
 #include "micro-ecc/uECC.h"
+#include "u2f.hpp"
+#include <iostream>
 #include <mbedtls/sha256.h>

 using namespace std;

 U2F_Authenticate_APDU::U2F_Authenticate_APDU(const U2F_Msg_CMD& msg, const vector<uint8_t>& data)
-	: U2F_Msg_CMD{ msg }
-{
-	if (p2 != 0)
-	{
+    : U2F_Msg_CMD{ msg } {
+	if (p2 != 0) {
 		// Invalid U2F (APDU) parameter detected
 		throw APDU_STATUS::SW_CONDITIONS_NOT_SATISFIED;
-	}
-	else if (data.size() < 66)
-	{
+	} else if (data.size() < 66) {
 		// Invalid authentication request
 		throw APDU_STATUS::SW_WRONG_LENGTH;
 	}
@@ -51,10 +47,8 @@ U2F_Authenticate_APDU::U2F_Authenticate_APDU(const U2F_Msg_CMD &msg, const vecto
 	copy(data.begin() + 65, data.begin() + 65 + keyHLen, back_inserter(keyH));
 }

-void U2F_Authenticate_APDU::respond(const uint32_t channelID) const
-{
-	if (keyH.size() != sizeof(Storage::KeyHandle))
-	{
+void U2F_Authenticate_APDU::respond(const uint32_t channelID) const {
+	if (keyH.size() != sizeof(Storage::KeyHandle)) {
 		// Respond with error code - key handle is of wrong size
 		cerr << "Invalid key handle length" << endl;
 		this->error(channelID, APDU_STATUS::SW_WRONG_DATA);
@@ -63,33 +57,23 @@ void U2F_Authenticate_APDU::respond(const uint32_t channelID) const

 	auto keyHB = *reinterpret_cast<const Storage::KeyHandle*>(keyH.data());

-	if (Storage::appParams.find(keyHB) == Storage::appParams.end())
-	{
+	if (Storage::appParams.find(keyHB) == Storage::appParams.end()) {
 		// Respond with error code - key handle doesn't exist in storage
 		cerr << "Invalid key handle" << endl;
-		this->error(channelID, SW_WRONG_DATA);
+		this->error(channelID, APDU_STATUS::SW_WRONG_DATA);
 		return;
 	}

 	auto appMatches = (Storage::appParams.at(keyHB) == appParam);

-	U2FMessage msg{};
-	msg.cid = channelID;
-	msg.cmd = U2FHID_MSG;
+	if (!appMatches) {
+		this->error(channelID, APDU_STATUS::SW_WRONG_DATA);
+		return;
+	}

-	auto &response = msg.data;
-	APDU_STATUS statusCode = APDU_STATUS::SW_NO_ERROR;
-
-	switch (p1)
-	{
+	switch (p1) {
 		case ControlCode::CheckOnly:
-			if (appMatches)
-				statusCode = APDU_STATUS::SW_CONDITIONS_NOT_SATISFIED;
-			else
-				statusCode = APDU_STATUS::SW_WRONG_DATA;
-
-			response.insert(response.end(), FIELD_BE(statusCode));
-			msg.write();
+			this->error(channelID, APDU_STATUS::SW_CONDITIONS_NOT_SATISFIED);
 			return;
 		case ControlCode::EnforcePresenceSign:
 			// Continue processing
@@ -103,6 +87,13 @@ void U2F_Authenticate_APDU::respond(const uint32_t channelID) const
 			return;
 	}

+	U2FMessage msg{};
+	msg.cid = channelID;
+	msg.cmd = U2FHID_MSG;
+
+	auto& response = msg.data;
+	APDU_STATUS statusCode = APDU_STATUS::SW_NO_ERROR;
+
 	const auto& privKey = Storage::privKeys[keyHB];
 	auto& keyCount = Storage::keyCounts[keyHB];
 	keyCount++;
@@ -117,7 +108,8 @@ void U2F_Authenticate_APDU::respond(const uint32_t channelID) const
 		mbedtls_sha256_init(&shaContext);
 		mbedtls_sha256_starts(&shaContext, 0);

-		mbedtls_sha256_update(&shaContext, reinterpret_cast<const uint8_t *>(appParam.data()), sizeof(appParam));
+		mbedtls_sha256_update(&shaContext, reinterpret_cast<const uint8_t*>(appParam.data()),
+		                      sizeof(appParam));
 		uint8_t userPresence{ 1u };
 		mbedtls_sha256_update(&shaContext, &userPresence, 1);
 		const auto beCounter = beEncode(keyCount);
--- a/U2F_Authenticate_APDU.hpp
+++ b/U2F_Authenticate_APDU.hpp
@@ -17,11 +17,11 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

 #pragma once
-#include "U2F_Msg_CMD.hpp"
 #include "Storage.hpp"
+#include "U2F_Msg_CMD.hpp"

-struct U2F_Authenticate_APDU : U2F_Msg_CMD
-{
+class U2F_Authenticate_APDU : public U2F_Msg_CMD {
+protected:
 	uint8_t controlByte;
 	std::array<uint8_t, 32> challengeP;
 	Storage::AppParam appParam;
@@ -32,8 +32,8 @@ struct U2F_Authenticate_APDU : U2F_Msg_CMD

 	virtual void respond(const uint32_t channelID) const override;

-	enum ControlCode
-	{
+protected:
+	enum ControlCode {
 		CheckOnly = 0x07,
 		EnforcePresenceSign = 0x03,
 		DontEnforcePresenceSign = 0x08
--- a/U2F_CMD.cpp
+++ b/U2F_CMD.cpp
@@ -17,19 +17,16 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

 #include "U2F_CMD.hpp"
-#include "u2f.hpp"
-#include "U2F_Msg_CMD.hpp"
 #include "U2F_Init_CMD.hpp"
+#include "U2F_Msg_CMD.hpp"
 #include "U2F_Ping_CMD.hpp"
+#include "u2f.hpp"

 using namespace std;

-shared_ptr<U2F_CMD> U2F_CMD::get(const shared_ptr<U2FMessage> uMsg)
-{
-	try
-	{
-		switch (uMsg->cmd)
-		{
+shared_ptr<U2F_CMD> U2F_CMD::get(const shared_ptr<U2FMessage> uMsg) {
+	try {
+		switch (uMsg->cmd) {
 			case U2FHID_PING:
 				return make_shared<U2F_Ping_CMD>(uMsg);
 			case U2FHID_MSG:
@@ -40,9 +37,7 @@ shared_ptr<U2F_CMD> U2F_CMD::get(const shared_ptr<U2FMessage> uMsg)
 				U2FMessage::error(uMsg->cid, ERR_INVALID_CMD);
 				return {};
 		}
-	}
-	catch (runtime_error& ignored)
-	{
+	} catch (runtime_error& ignored) {
 		U2FMessage::error(uMsg->cid, ERR_OTHER);
 		return {};
 	}
--- a/U2F_CMD.hpp
+++ b/U2F_CMD.hpp
@@ -17,11 +17,10 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

 #pragma once
-#include <memory>
 #include "U2FMessage.hpp"
+#include <memory>

-struct U2F_CMD
-{
+class U2F_CMD {
 protected:
 	U2F_CMD() = default;

@@ -29,4 +28,5 @@ struct U2F_CMD
 	virtual ~U2F_CMD() = default;
 	static std::shared_ptr<U2F_CMD> get(const std::shared_ptr<U2FMessage> uMsg);
 	virtual void respond(const uint32_t channelID) const = 0;
+	virtual bool modifiesPersistentState() const = 0;
 }; // For polymorphic type casting
--- a/U2F_Init_CMD.cpp
+++ b/U2F_Init_CMD.cpp
@@ -17,23 +17,19 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

 #include "U2F_Init_CMD.hpp"
-#include <stdexcept>
-#include "u2f.hpp"
 #include "Field.hpp"
+#include "u2f.hpp"
+#include <stdexcept>

 using namespace std;

-U2F_Init_CMD::U2F_Init_CMD(const shared_ptr<U2FMessage> uMsg)
-{
+U2F_Init_CMD::U2F_Init_CMD(const shared_ptr<U2FMessage> uMsg) {
 	if (uMsg->cmd != U2FHID_INIT)
 		throw runtime_error{ "Failed to get U2F Init message" };
-	else if (uMsg->cid != CID_BROADCAST)
-	{
+	else if (uMsg->cid != CID_BROADCAST) {
 		U2FMessage::error(uMsg->cid, ERR_OTHER);
 		throw runtime_error{ "Invalid CID for init command" };
-	}
-	else if (uMsg->data.size() != INIT_NONCE_SIZE)
-	{
+	} else if (uMsg->data.size() != INIT_NONCE_SIZE) {
 		U2FMessage::error(uMsg->cid, ERR_INVALID_LEN);
 		throw runtime_error{ "Init nonce is incorrect size" };
 	}
@@ -41,8 +37,7 @@ U2F_Init_CMD::U2F_Init_CMD(const shared_ptr<U2FMessage> uMsg)
 	this->nonce = *reinterpret_cast<const uint64_t*>(uMsg->data.data());
 }

-void U2F_Init_CMD::respond(const uint32_t channelID) const
-{
+void U2F_Init_CMD::respond(const uint32_t channelID) const {
 	U2FMessage msg{};
 	msg.cid = CID_BROADCAST;
 	msg.cmd = U2FHID_INIT;
@@ -57,3 +52,7 @@ void U2F_Init_CMD::respond(const uint32_t channelID) const

 	msg.write();
 }
+
+bool U2F_Init_CMD::modifiesPersistentState() const {
+	return false;
+}
--- a/U2F_Init_CMD.hpp
+++ b/U2F_Init_CMD.hpp
@@ -17,16 +17,17 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

 #pragma once
+#include "U2FMessage.hpp"
+#include "U2F_CMD.hpp"
 #include <cstdint>
 #include <memory>
-#include "U2F_CMD.hpp"
-#include "U2FMessage.hpp"

-struct U2F_Init_CMD : U2F_CMD
-{
+class U2F_Init_CMD : public U2F_CMD {
+protected:
 	uint64_t nonce;

 public:
 	U2F_Init_CMD(const std::shared_ptr<U2FMessage> uMsg);
 	virtual void respond(const uint32_t channelID) const override;
+	virtual bool modifiesPersistentState() const override;
 };
--- a/U2F_Msg_CMD.cpp
+++ b/U2F_Msg_CMD.cpp
@@ -18,26 +18,22 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.

 #include "U2F_Msg_CMD.hpp"
 #include "APDU.hpp"
+#include "Field.hpp"
+#include "Streams.hpp"
+#include "U2FMessage.hpp"
+#include "U2F_Authenticate_APDU.hpp"
 #include "U2F_Register_APDU.hpp"
 #include "U2F_Version_APDU.hpp"
-#include "U2F_Authenticate_APDU.hpp"
-#include "U2FMessage.hpp"
 #include "u2f.hpp"
-#include "APDU.hpp"
 #include <iostream>
-#include "Streams.hpp"
-#include "Field.hpp"

 using namespace std;

-uint32_t U2F_Msg_CMD::getLe(const uint32_t byteCount, vector<uint8_t> bytes)
-{
-	if (byteCount != 0)
-	{
+uint32_t U2F_Msg_CMD::getLe(const uint32_t byteCount, vector<uint8_t> bytes) {
+	if (byteCount != 0) {
 		// Le must be length of data in bytes

-		switch (byteCount)
-		{
+		switch (byteCount) {
 			case 1:
 				return (bytes[0] == 0 ? 256 : bytes[0]);
 			case 2:
@@ -55,17 +51,14 @@ uint32_t U2F_Msg_CMD::getLe(const uint32_t byteCount, vector<uint8_t> bytes)
 			default:
 				throw runtime_error{ "Too much data for command" };
 		}
-	}
-	else
+	} else
 		return 0;
 }

-shared_ptr<U2F_Msg_CMD> U2F_Msg_CMD::generate(const shared_ptr<U2FMessage> uMsg)
-{
+shared_ptr<U2F_Msg_CMD> U2F_Msg_CMD::generate(const shared_ptr<U2FMessage> uMsg) {
 	if (uMsg->cmd != U2FHID_MSG)
 		throw runtime_error{ "Failed to get U2F Msg uMsg" };
-	else if (uMsg->data.size() < 4)
-	{
+	else if (uMsg->data.size() < 4) {
 		U2F_Msg_CMD::error(uMsg->cid, APDU_STATUS::SW_WRONG_LENGTH);
 		throw runtime_error{ "Msg data is incorrect size" };
 	}
@@ -75,8 +68,7 @@ shared_ptr<U2F_Msg_CMD> U2F_Msg_CMD::generate(const shared_ptr<U2FMessage> uMsg)

 	cmd.cla = dat[0];

-	if (cmd.cla != 0)
-	{
+	if (cmd.cla != 0) {
 		U2F_Msg_CMD::error(uMsg->cid, APDU_STATUS::SW_COMMAND_NOT_ALLOWED);
 		throw runtime_error{ "Invalid CLA value in U2F Message" };
 	}
@@ -89,10 +81,13 @@ shared_ptr<U2F_Msg_CMD> U2F_Msg_CMD::generate(const shared_ptr<U2FMessage> uMsg)
 	const uint32_t cBCount = data.size();
 	auto startPtr = data.begin(), endPtr = data.end();

-	if (usesData.at(cmd.ins) || data.size() > 3)
-	{
-		if (cBCount == 0)
-		{
+	const auto cmdUsesData = usesData.find(cmd.ins);
+
+	if (cmdUsesData == usesData.end()) {
+		U2F_Msg_CMD::error(uMsg->cid, APDU_STATUS::SW_INS_NOT_SUPPORTED);
+		throw runtime_error{ "Unknown instruction: unsure if uses data" };
+	} else if (cmdUsesData->second || data.size() > 3) {
+		if (cBCount == 0) {
 			U2F_Msg_CMD::error(uMsg->cid, APDU_STATUS::SW_WRONG_LENGTH);
 			throw runtime_error{ "Invalid command - should have attached data" };
 		}
@@ -101,36 +96,26 @@ shared_ptr<U2F_Msg_CMD> U2F_Msg_CMD::generate(const shared_ptr<U2FMessage> uMsg)
 		{
 			cmd.lc = data[0];
 			startPtr++;
-		}
-		else
-		{
+		} else {
 			cmd.lc = (data[1] << 8) + data[2];
 			startPtr += 3;
 		}

 		endPtr = startPtr + cmd.lc;

-		try
-		{
+		try {
 			cmd.le = getLe(data.end() - endPtr, vector<uint8_t>(endPtr, data.end()));
-		}
-		catch (runtime_error& ignored)
-		{
+		} catch (runtime_error& ignored) {
 			U2F_Msg_CMD::error(uMsg->cid, APDU_STATUS::SW_WRONG_LENGTH);
 			throw;
 		}
-	}
-	else
-	{
+	} else {
 		cmd.lc = 0;
 		endPtr = startPtr;

-		try
-		{
+		try {
 			cmd.le = getLe(cBCount, data);
-		}
-		catch (runtime_error& ignored)
-		{
+		} catch (runtime_error& ignored) {
 			U2F_Msg_CMD::error(uMsg->cid, APDU_STATUS::SW_WRONG_LENGTH);
 			throw;
 		}
@@ -141,7 +126,8 @@ shared_ptr<U2F_Msg_CMD> U2F_Msg_CMD::generate(const shared_ptr<U2FMessage> uMsg)
 #ifdef DEBUG_STREAMS
 	auto hAS = getHostAPDUStream().get();

-	fprintf(hAS, "<table>\n"
+	fprintf(hAS,
+	        "<table>\n"
 	        "\t\t\t<thead>\n"
 	        "\t\t\t\t<tr>\n"
 	        "\t\t\t\t\t<th>CLA</th>\n"
@@ -160,23 +146,24 @@ shared_ptr<U2F_Msg_CMD> U2F_Msg_CMD::generate(const shared_ptr<U2FMessage> uMsg)
 	        "\t\t\t\t\t<td>%u</td>\n"
 	        "\t\t\t\t\t<td>%u</td>\n"
 	        "\t\t\t\t\t<td>%3u</td>\n"
-			"\t\t\t\t\t<td class=\"data\">", cmd.cla, cmd.ins, cmd.p1, cmd.p2, cmd.lc);
+	        "\t\t\t\t\t<td class=\"data\">",
+	        cmd.cla, cmd.ins, cmd.p1, cmd.p2, cmd.lc);

 	for (auto b : dBytes)
 		fprintf(hAS, "%3u ", b);

-	fprintf(hAS, "</td>\n"
+	fprintf(hAS,
+	        "</td>\n"
 	        "\t\t\t\t\t<td>%5u</td>\n"
 	        "\t\t\t\t</tr>\n"
 	        "\t\t\t</tbody>\n"
 	        "\t\t</table>\n"
-			"\t\t<br />", cmd.le);
+	        "\t\t<br />",
+	        cmd.le);
 #endif

-	try
-	{
-		switch (cmd.ins)
-		{
+	try {
+		switch (cmd.ins) {
 			case APDU::U2F_REG:
 				return make_shared<U2F_Register_APDU>(cmd, dBytes);
 			case APDU::U2F_AUTH:
@@ -187,17 +174,14 @@ shared_ptr<U2F_Msg_CMD> U2F_Msg_CMD::generate(const shared_ptr<U2FMessage> uMsg)
 				cerr << "Invalid command used" << endl;
 				throw APDU_STATUS::SW_INS_NOT_SUPPORTED;
 		}
-	}
-	catch (const APDU_STATUS e)
-	{
+	} catch (const APDU_STATUS e) {
 		U2F_Msg_CMD::error(uMsg->cid, e);
 		throw runtime_error{ "APDU construction error" };
 		return {};
 	}
 }

-void U2F_Msg_CMD::error(const uint32_t channelID, const uint16_t errCode)
-{
+void U2F_Msg_CMD::error(const uint32_t channelID, const uint16_t errCode) {
 	clog << "U2F_Msg_CMD::error " << errCode << endl;
 	U2FMessage msg{};
 	msg.cid = channelID;
@@ -206,13 +190,17 @@ void U2F_Msg_CMD::error(const uint32_t channelID, const uint16_t errCode)
 	msg.write();
 }

-const map<uint8_t, bool> U2F_Msg_CMD::usesData = {
-	{ U2F_REG,  true  },
+const map<uint8_t, bool> U2F_Msg_CMD::usesData = { { U2F_REG, true },
 	                                               { U2F_AUTH, true },
-	{ U2F_VER,  false }
-};
+	                                               { U2F_VER, false } };

-void U2F_Msg_CMD::respond(const uint32_t channelID) const
-{
+void U2F_Msg_CMD::respond(const uint32_t channelID) const {
 	U2F_Msg_CMD::error(channelID, static_cast<uint16_t>(APDU_STATUS::SW_INS_NOT_SUPPORTED));
 }
+
+bool U2F_Msg_CMD::modifiesPersistentState() const {
+	const auto usesPersistentState = usesData.find(ins);
+
+	// Be conservative for future instructions. Assume that they do modify persist state.
+	return (usesPersistentState == usesData.end()) || usesPersistentState->second;
+}
--- a/U2F_Msg_CMD.hpp
+++ b/U2F_Msg_CMD.hpp
@@ -20,11 +20,10 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 #include "U2F_CMD.hpp"
 #include <cstdint>
 #include <map>
-#include <vector>
 #include <memory>
+#include <vector>

-struct U2F_Msg_CMD : U2F_CMD
-{
+struct U2F_Msg_CMD : public U2F_CMD {
 	uint8_t cla;
 	uint8_t ins;
 	uint8_t p1;
@@ -41,6 +40,6 @@ struct U2F_Msg_CMD : U2F_CMD
 public:
 	static std::shared_ptr<U2F_Msg_CMD> generate(const std::shared_ptr<U2FMessage> uMsg);
 	static void error(const uint32_t channelID, const uint16_t errCode);
-		void respond(const uint32_t channelID) const;
+	void respond(const uint32_t channelID) const override;
+	virtual bool modifiesPersistentState() const override;
 };
-
--- a/U2F_Ping_CMD.cpp
+++ b/U2F_Ping_CMD.cpp
@@ -21,18 +21,19 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.

 using namespace std;

-U2F_Ping_CMD::U2F_Ping_CMD(const shared_ptr<U2FMessage> uMsg)
-	: nonce{ uMsg->data }
-{
+U2F_Ping_CMD::U2F_Ping_CMD(const shared_ptr<U2FMessage> uMsg) : nonce{ uMsg->data } {
 	if (uMsg->cmd != U2FHID_PING)
 		throw runtime_error{ "Failed to get U2F ping message" };
 }

-void U2F_Ping_CMD::respond(const uint32_t channelID) const
-{
+void U2F_Ping_CMD::respond(const uint32_t channelID) const {
 	U2FMessage msg{};
 	msg.cid = channelID;
 	msg.cmd = U2FHID_PING;
 	msg.data = nonce;
 	msg.write();
 }
+
+bool U2F_Ping_CMD::modifiesPersistentState() const {
+	return false;
+}
--- a/U2F_Ping_CMD.hpp
+++ b/U2F_Ping_CMD.hpp
@@ -17,16 +17,17 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

 #pragma once
+#include "U2FMessage.hpp"
+#include "U2F_CMD.hpp"
 #include <cstdint>
 #include <memory>
-#include "U2F_CMD.hpp"
-#include "U2FMessage.hpp"

-struct U2F_Ping_CMD : U2F_CMD
-{
+class U2F_Ping_CMD : public U2F_CMD {
+protected:
 	std::vector<uint8_t> nonce;

 public:
 	U2F_Ping_CMD(const std::shared_ptr<U2FMessage> uMsg);
 	virtual void respond(const uint32_t channelID) const override;
+	virtual bool modifiesPersistentState() const override;
 };
--- a/U2F_Register_APDU.cpp
+++ b/U2F_Register_APDU.cpp
@@ -17,28 +17,25 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

 #include "U2F_Register_APDU.hpp"
-#include <exception>
-#include <cstring>
-#include "micro-ecc/uECC.h"
-#include "Certificates.hpp"
-#include <mbedtls/sha256.h>
-#include <iostream>
 #include "APDU.hpp"
-#include "U2FMessage.hpp"
-#include "u2f.hpp"
+#include "Certificates.hpp"
 #include "Signature.hpp"
+#include "U2FMessage.hpp"
+#include "micro-ecc/uECC.h"
+#include "u2f.hpp"
+#include <cstring>
+#include <exception>
+#include <iostream>
+#include <mbedtls/sha256.h>

 using namespace std;

 U2F_Register_APDU::U2F_Register_APDU(const U2F_Msg_CMD& msg, const vector<uint8_t>& data)
-	: U2F_Msg_CMD{ msg }
-{
-	if (data.size() != 64)
-	{
+    : U2F_Msg_CMD{ msg } {
+	if (data.size() != 64) {
 		// Incorrect registration size
 		throw APDU_STATUS::SW_WRONG_LENGTH;
-	}
-	else if ((p1 != 0x00 && p1 != 0x03) || p2 != 0x00) //According to spec, 0x03 not allowed here
+	} else if ((p1 != 0x00 && p1 != 0x03) || p2 != 0x00) // According to spec, 0x03 not allowed here
 	                                                     // However, browsers seem to do it, so...
 	{
 		// Invalid U2F Message (APDU) parameters detected
@@ -64,8 +61,7 @@ U2F_Register_APDU::U2F_Register_APDU(const U2F_Msg_CMD &msg, const vector<uint8_
 	Storage::keyCounts[this->keyH] = 0;
 }

-void U2F_Register_APDU::respond(const uint32_t channelID) const
-{
+void U2F_Register_APDU::respond(const uint32_t channelID) const {
 	U2FMessage m{};
 	m.cid = channelID;
 	m.cmd = U2FHID_MSG;
@@ -94,13 +90,18 @@ void U2F_Register_APDU::respond(const uint32_t channelID) const
 		uint8_t byteReserved = 0;
 		mbedtls_sha256_update(&shaContext, reinterpret_cast<unsigned char*>(&byteReserved), 1);

-		mbedtls_sha256_update(&shaContext, reinterpret_cast<const unsigned char*>(appParam.data()), appParam.size());
+		mbedtls_sha256_update(&shaContext, reinterpret_cast<const unsigned char*>(appParam.data()),
+		                      appParam.size());

-		mbedtls_sha256_update(&shaContext, reinterpret_cast<const unsigned char*>(challengeP.data()), challengeP.size());
+		mbedtls_sha256_update(&shaContext,
+		                      reinterpret_cast<const unsigned char*>(challengeP.data()),
+		                      challengeP.size());

-		mbedtls_sha256_update(&shaContext, reinterpret_cast<const unsigned char*>(&keyH), sizeof(keyH));
+		mbedtls_sha256_update(&shaContext, reinterpret_cast<const unsigned char*>(&keyH),
+		                      sizeof(keyH));

-		mbedtls_sha256_update(&shaContext, reinterpret_cast<const unsigned char*>(pubKey.data()), pubKey.size());
+		mbedtls_sha256_update(&shaContext, reinterpret_cast<const unsigned char*>(pubKey.data()),
+		                      pubKey.size());

 		mbedtls_sha256_finish(&shaContext, digest.data());
 		mbedtls_sha256_free(&shaContext);
--- a/U2F_Register_APDU.hpp
+++ b/U2F_Register_APDU.hpp
@@ -17,11 +17,11 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

 #pragma once
-#include "U2F_Msg_CMD.hpp"
 #include "Storage.hpp"
+#include "U2F_Msg_CMD.hpp"

-struct U2F_Register_APDU : U2F_Msg_CMD
-{
+class U2F_Register_APDU : public U2F_Msg_CMD {
+protected:
 	std::array<uint8_t, 32> challengeP;
 	Storage::AppParam appP;
 	Storage::KeyHandle keyH;
@@ -31,4 +31,3 @@ struct U2F_Register_APDU : U2F_Msg_CMD

 	void respond(const uint32_t channelID) const override;
 };
-
--- a/U2F_Version_APDU.cpp
+++ b/U2F_Version_APDU.cpp
@@ -17,16 +17,15 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

 #include "U2F_Version_APDU.hpp"
-#include <iostream>
+#include "APDU.hpp"
+#include "Field.hpp"
 #include "U2FMessage.hpp"
 #include "u2f.hpp"
-#include "Field.hpp"
-#include "APDU.hpp"
+#include <iostream>

 using namespace std;

-U2F_Version_APDU::U2F_Version_APDU(const U2F_Msg_CMD &msg, const std::vector<uint8_t> &data)
-{
+U2F_Version_APDU::U2F_Version_APDU(const U2F_Msg_CMD& msg, const std::vector<uint8_t>& data) {
 	// Don't actually respond yet unless invalid
 	if (msg.p1 != 0 || msg.p2 != 0)
 		throw APDU_STATUS::SW_INS_NOT_SUPPORTED;
@@ -34,8 +33,7 @@ U2F_Version_APDU::U2F_Version_APDU(const U2F_Msg_CMD &msg, const std::vector<uin
 		throw APDU_STATUS::SW_WRONG_LENGTH;
 }

-void U2F_Version_APDU::respond(const uint32_t channelID) const
-{
+void U2F_Version_APDU::respond(const uint32_t channelID) const {
 	char ver[]{ 'U', '2', 'F', '_', 'V', '2' };
 	U2FMessage m{};

--- a/U2F_Version_APDU.hpp
+++ b/U2F_Version_APDU.hpp
@@ -19,8 +19,7 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 #pragma once
 #include "U2F_Msg_CMD.hpp"

-struct U2F_Version_APDU : U2F_Msg_CMD
-{
+class U2F_Version_APDU : public U2F_Msg_CMD {
 public:
 	U2F_Version_APDU(const U2F_Msg_CMD& msg, const std::vector<uint8_t>& data);
 	void respond(const uint32_t channelID) const override;
--- a/main.cpp
+++ b/main.cpp
@@ -1,17 +1,15 @@
-#include "U2FDevice.hpp"
 #include "Architecture.hpp"
+#include "U2FDevice.hpp"
 #include <execinfo.h>
 #include <iostream>

 #ifdef DEBUG_MSGS
 // Courtesy StackOverflow answer https://stackoverflow.com/a/3356421
-void terminateHandler()
-{
+void terminateHandler() {
 	void* trace_elems[20];
 	int trace_elem_count(backtrace(trace_elems, 20));
 	char** stack_syms(backtrace_symbols(trace_elems, trace_elem_count));
-    for (int i = 0; i < trace_elem_count; ++i)
-    {
+	for (int i = 0; i < trace_elem_count; ++i) {
 		std::cout << stack_syms[i] << "\n";
 	}
 	free(stack_syms);
@@ -22,17 +20,14 @@ void terminateHandler()

 int main(int argc, char** argv) {
 #ifdef DEBUG_MSGS
-	std::set_terminate(terminate_handler);
+	std::set_terminate(terminateHandler);
 #endif
 	int retCode = handleTransactions(argv[0], argc == 2 ? argv[1] : STORAGE_PREFIX);

-	try
-	{
+	try {
 		initialiseLights(argv[0]);
 		deinitialiseLights(argv[0]);
-	}
-	catch (std::exception &e)
-	{
+	} catch (std::exception& e) {
 		std::cerr << "Exception in code: " << e.what() << std::endl;
 		throw;
 	}
--- a/u2f.hpp
+++ b/u2f.hpp
@@ -124,4 +124,3 @@ typedef struct {
 #endif

 #endif // __U2FHID_H_INCLUDED__
-
Author	SHA1	Message	Date
Michael Kuc	1093294b61	Fix visability issues.	2019-09-14 09:24:03 +01:00
Michael Kuc	ed1add2c60	Fix #6 . Fix relying party verification. Fix to throw error when relying party uses the wrong application parameter when requesting a signature.	2019-09-11 15:49:50 +01:00
Michael Kuc	c8061d373f	Updated READMEs with new certificate details.	2019-09-10 10:52:02 +01:00
Michael Kuc	784f3803f9	Fixed typo in Certificates.hpp. Updated GenCErtificates.sh script to accomodate change.	2019-09-10 10:51:32 +01:00
Michael Kuc	7ce0738338	Implemented automated certificate generation. Removed existing certificates as private key was shared. Updated makefile to require certificate generation.	2019-09-09 17:06:47 +01:00
Michael Kuc	701127496c	Additional error handling for rarer states. Ensure std::map::at is not blindly applied without checking that the key actually exists. Fixes crashes where u2f client on PC/browser expects channel open, but service has been restarted.	2019-09-08 20:27:47 +01:00
Michael Kuc	528662a081	Fix missing signal handling. Plug signal handler into additional signal. Fixes no cleanup (corruption) on stopping. May impact #6.	2019-09-08 20:25:36 +01:00
Michael Kuc	80b552012d	Fixed constant re-opening kernel pipe.	2019-09-07 17:23:41 +01:00
Michael Kuc	aeb9c89be8	Save immediately on persistent state modification. Modifications for #6.	2019-08-29 16:20:42 +01:00
Michael Kuc	ad250d14e3	Fixed U2FDevice attempting to update every microsecond.	2019-08-23 13:37:51 +01:00
Michael Kuc	f7dea03132	Reformat	2019-08-23 13:32:41 +01:00
Michael Kuc	55d1fd738f	Update gitignore. Added clang-formatting specification.	2019-08-23 13:32:03 +01:00
Michael Kuc	0ce5793414	Hopefully improved attestation certificate creation README. Fixes #3.	2019-08-05 13:00:50 +01:00
Michael Kuc	4ce52d4da3	Replaced incorrect `#if` with `#ifdef`. Fixes #2.	2019-08-05 12:49:59 +01:00
Michael Kuc	a426a70dcf	Fixed terminateHandler typo. Fixes #1.	2019-08-05 12:31:06 +01:00
Michael Kuc	c0ca093e83	Fixed branch path.	2019-06-26 16:56:02 +01:00
Michael Kuc	fc96017efd	Refer to android branch on main readme.	2019-06-26 16:53:29 +01:00
Michael Kuc	b942713cc9	Correct architecture.	2019-06-26 13:09:20 +01:00
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