Add WiFiClientSecure and WifiServerSecure (TLS) support, NTP (#683)

* Add TLS (https) support
* Add NTP server
* Clean up include path, add BearSSL headers
* Allow 2 NTP servers, add ESP8266 compat define
* Add MFLN SSL example, free/used/total heap getters
* Enable stack thunking
* Add tested SSL examples
* Add BSSL_validation demo
* Add Client Certificate example
* Add RP2040 helper docs
* Clean up doc errors, missing doc version info
* Add WiFiClientSecure documentation
* Add NTP docs

Fixes #679

Author: earlephilhower

.github/workflows/pull-request.yml

@@ -20,7 +20,7 @@ jobs:
     - name: Run codespell
       uses: codespell-project/actions-codespell@master
       with:
-        skip: ./ArduinoCore-API,./libraries/ESP8266SdFat,./libraries/Adafruit_TinyUSB_Arduino,./libraries/LittleFS/lib,./tools/pyserial,./pico-sdk,./.github,./docs/i2s.rst,./cores/rp2040/api,./libraries/FreeRTOS
+        skip: ./ArduinoCore-API,./libraries/ESP8266SdFat,./libraries/Adafruit_TinyUSB_Arduino,./libraries/LittleFS/lib,./tools/pyserial,./pico-sdk,./.github,./docs/i2s.rst,./cores/rp2040/api,./libraries/FreeRTOS,./tools/libbearssl/bearssl,./include,./libraries/WiFi/examples/BearSSL_Server
         ignore_words_list: ser,dout
 
 # Consistent style
@@ -211,4 +211,4 @@ jobs:
     - name: Build Fade Example
       run: pio ci --board=rpipico --board=adafruit_feather -O "platform_packages=framework-arduinopico@symlink:///home/runner/work/arduino-pico/arduino-pico" libraries/rp2040/examples/Fade/Fade.ino
     - name: Build TinyUSB Example
-      run: pio ci --board=rpipico --board=adafruit_feather -O "platform_packages=framework-arduinopico@symlink:///home/runner/work/arduino-pico/arduino-pico" -O "build_flags=-DUSE_TINYUSB" libraries/Adafruit_TinyUSB_Arduino/examples/CDC/cdc_multi/cdc_multi.ino
+      run: pio ci --board=rpipico --board=adafruit_feather -O "platform_packages=framework-arduinopico@symlink:///home/runner/work/arduino-pico/arduino-pico" -O "build_flags=-DUSE_TINYUSB" libraries/Adafruit_TinyUSB_Arduino/examples/CDC/cdc_multi/cdc_multi.ino

.gitmodules

@@ -25,3 +25,6 @@
 [submodule "libraries/FreeRTOS/lib/FreeRTOS-Kernel"]
 	path = libraries/FreeRTOS/lib/FreeRTOS-Kernel
 	url = https://github.com/earlephilhower/FreeRTOS-Kernel.git
+[submodule "tools/libbearssl/bearssl"]
+	path = tools/libbearssl/bearssl
+	url = https://github.com/earlephilhower/bearssl-esp8266.git

cores/rp2040/PolledTimeout.h

@@ -0,0 +1,290 @@
+/*
+    PolledTimeout.h - Encapsulation of a polled Timeout
+
+    Copyright (c) 2018 Daniel Salazar. All rights reserved.
+    This file is part of the esp8266 core for Arduino environment.
+
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Lesser General Public
+    License as published by the Free Software Foundation; either
+    version 2.1 of the License, or (at your option) any later version.
+
+    This library 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
+    Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public
+    License along with this library; if not, write to the Free Software
+    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+
+#pragma once
+
+#include <limits>                  // std::numeric_limits
+#include <type_traits>             // std::is_unsigned
+
+#define IRAM_ATTR
+
+namespace esp8266 {
+
+
+namespace polledTimeout {
+
+namespace YieldPolicy {
+
+struct DoNothing {
+    static void execute() {}
+};
+
+struct YieldOrSkip {
+    static void execute() {} //{esp_yield();}
+};
+
+template <unsigned long delayMs>
+struct YieldAndDelayMs {
+    static void execute() {
+        delay(delayMs);
+    }
+};
+
+} //YieldPolicy
+
+namespace TimePolicy {
+
+struct TimeSourceMillis {
+    // time policy in milli-seconds based on millis()
+
+    using timeType = decltype(millis());
+    static timeType time() {
+        return millis();
+    }
+    static constexpr timeType ticksPerSecond    = 1000;
+    static constexpr timeType ticksPerSecondMax = 1000;
+};
+
+struct TimeSourceCycles {
+    // time policy based on esp_get_cycle_count()
+    // this particular time measurement is intended to be called very often
+    // (every loop, every yield)
+
+    using timeType = decltype(rp2040.getCycleCount());
+    static timeType time() {
+        return rp2040.getCycleCount();
+    }
+    static constexpr timeType ticksPerSecond    = F_CPU;
+    static constexpr timeType ticksPerSecondMax = F_CPU;
+};
+
+template <typename TimeSourceType, unsigned long long second_th>
+// "second_th" units of timeType for one second
+struct TimeUnit {
+    using timeType = typename TimeSourceType::timeType;
+
+#if __GNUC__ < 5
+    // gcc-4.8 cannot compile the constexpr-only version of this function
+    // using #defines instead luckily works
+    static constexpr timeType computeRangeCompensation() {
+#define number_of_secondTh_in_one_tick ((1.0 * second_th) / ticksPerSecond)
+#define fractional (number_of_secondTh_in_one_tick - (long)number_of_secondTh_in_one_tick)
+
+        return ({
+            fractional == 0 ?
+            1 : // no need for compensation
+            (number_of_secondTh_in_one_tick / fractional) + 0.5; // scalar multiplier allowing exact division
+        });
+
+#undef number_of_secondTh_in_one_tick
+#undef fractional
+    }
+#else
+    static constexpr timeType computeRangeCompensation() {
+        return ({
+            constexpr double number_of_secondTh_in_one_tick = (1.0 * second_th) / ticksPerSecond;
+            constexpr double fractional = number_of_secondTh_in_one_tick - (long)number_of_secondTh_in_one_tick;
+            fractional == 0 ?
+            1 : // no need for compensation
+            (number_of_secondTh_in_one_tick / fractional) + 0.5; // scalar multiplier allowing exact division
+        });
+    }
+#endif
+
+    static constexpr timeType ticksPerSecond         = TimeSourceType::ticksPerSecond;
+    static constexpr timeType ticksPerSecondMax      = TimeSourceType::ticksPerSecondMax;
+    static constexpr timeType rangeCompensate        = computeRangeCompensation();
+    static constexpr timeType user2UnitMultiplierMax = (ticksPerSecondMax * rangeCompensate) / second_th;
+    static constexpr timeType user2UnitMultiplier    = (ticksPerSecond    * rangeCompensate) / second_th;
+    static constexpr timeType user2UnitDivider       = rangeCompensate;
+    // std::numeric_limits<timeType>::max() is reserved
+    static constexpr timeType timeMax                = (std::numeric_limits<timeType>::max() - 1) / user2UnitMultiplierMax;
+
+    static timeType toTimeTypeUnit(const timeType userUnit) {
+        return (userUnit * user2UnitMultiplier) / user2UnitDivider;
+    }
+    static timeType toUserUnit(const timeType internalUnit) {
+        return (internalUnit * user2UnitDivider) / user2UnitMultiplier;
+    }
+    static timeType time() {
+        return TimeSourceType::time();
+    }
+};
+
+using TimeMillis     = TimeUnit< TimeSourceMillis,       1000 >;
+using TimeFastMillis = TimeUnit< TimeSourceCycles,       1000 >;
+using TimeFastMicros = TimeUnit< TimeSourceCycles,    1000000 >;
+using TimeFastNanos  = TimeUnit< TimeSourceCycles, 1000000000 >;
+
+} //TimePolicy
+
+template <bool PeriodicT, typename YieldPolicyT = YieldPolicy::DoNothing, typename TimePolicyT = TimePolicy::TimeMillis>
+class timeoutTemplate {
+public:
+    using timeType = typename TimePolicyT::timeType;
+    static_assert(std::is_unsigned<timeType>::value == true, "timeType must be unsigned");
+
+    static constexpr timeType alwaysExpired   = 0;
+    static constexpr timeType neverExpires    = std::numeric_limits<timeType>::max();
+    static constexpr timeType rangeCompensate = TimePolicyT::rangeCompensate; //debug
+
+    timeoutTemplate(const timeType userTimeout) {
+        reset(userTimeout);
+    }
+
+    IRAM_ATTR // fast
+    bool expired() {
+        YieldPolicyT::execute(); //in case of DoNothing: gets optimized away
+        if (PeriodicT) {        //in case of false: gets optimized away
+            return expiredRetrigger();
+        }
+        return expiredOneShot();
+    }
+
+    IRAM_ATTR // fast
+    operator bool() {
+        return expired();
+    }
+
+    bool canExpire() const {
+        return !_neverExpires;
+    }
+
+    bool canWait() const {
+        return _timeout != alwaysExpired;
+    }
+
+    // Resets, will trigger after this new timeout.
+    IRAM_ATTR // called from ISR
+    void reset(const timeType newUserTimeout) {
+        reset();
+        _timeout = TimePolicyT::toTimeTypeUnit(newUserTimeout);
+        _neverExpires = (newUserTimeout < 0) || (newUserTimeout > timeMax());
+    }
+
+    // Resets, will trigger after the timeout previously set.
+    IRAM_ATTR // called from ISR
+    void reset() {
+        _start = TimePolicyT::time();
+    }
+
+    // Resets to just expired so that on next poll the check will immediately trigger for the user,
+    // also change timeout (after next immediate trigger).
+    IRAM_ATTR // called from ISR
+    void resetAndSetExpired(const timeType newUserTimeout) {
+        reset(newUserTimeout);
+        _start -= _timeout;
+    }
+
+    // Resets to just expired so that on next poll the check will immediately trigger for the user.
+    IRAM_ATTR // called from ISR
+    void resetAndSetExpired() {
+        reset();
+        _start -= _timeout;
+    }
+
+    void resetToNeverExpires() {
+        _timeout = alwaysExpired + 1; // because canWait() has precedence
+        _neverExpires = true;
+    }
+
+    timeType getTimeout() const {
+        return TimePolicyT::toUserUnit(_timeout);
+    }
+
+    static constexpr timeType timeMax() {
+        return TimePolicyT::timeMax;
+    }
+
+private:
+
+    IRAM_ATTR // fast
+    bool checkExpired(const timeType internalUnit) const {
+        // canWait() is not checked here
+        // returns "can expire" and "time expired"
+        return (!_neverExpires) && ((internalUnit - _start) >= _timeout);
+    }
+
+protected:
+
+    IRAM_ATTR // fast
+    bool expiredRetrigger() {
+        if (!canWait()) {
+            return true;
+        }
+
+        timeType current = TimePolicyT::time();
+        if (checkExpired(current)) {
+            unsigned long n = (current - _start) / _timeout; //how many _timeouts periods have elapsed, will usually be 1 (current - _start >= _timeout)
+            _start += n  * _timeout;
+            return true;
+        }
+        return false;
+    }
+
+    IRAM_ATTR // fast
+    bool expiredOneShot() const {
+        // returns "always expired" or "has expired"
+        return !canWait() || checkExpired(TimePolicyT::time());
+    }
+
+    timeType _timeout;
+    timeType _start;
+    bool _neverExpires;
+};
+
+// legacy type names, deprecated (unit is milliseconds)
+
+using oneShot = polledTimeout::timeoutTemplate<false> /*__attribute__((deprecated("use oneShotMs")))*/;
+using periodic = polledTimeout::timeoutTemplate<true> /*__attribute__((deprecated("use periodicMs")))*/;
+
+// standard versions (based on millis())
+// timeMax() is 49.7 days ((2^32)-2 ms)
+
+using oneShotMs = polledTimeout::timeoutTemplate<false>;
+using periodicMs = polledTimeout::timeoutTemplate<true>;
+
+// Time policy based on esp_get_cycle_count(), and intended to be called very often:
+// "Fast" versions sacrifices time range for improved precision and reduced execution time (by 86%)
+// (cpu cycles for ::expired(): 372 (millis()) vs 52 (esp_get_cycle_count()))
+// timeMax() values:
+// Ms: max is 26843       ms (26.8  s)
+// Us: max is 26843545    us (26.8  s)
+// Ns: max is  1073741823 ns ( 1.07 s)
+// (time policy based on esp_get_cycle_count() is intended to be called very often)
+
+using oneShotFastMs = polledTimeout::timeoutTemplate<false, YieldPolicy::DoNothing, TimePolicy::TimeFastMillis>;
+using periodicFastMs = polledTimeout::timeoutTemplate<true, YieldPolicy::DoNothing, TimePolicy::TimeFastMillis>;
+using oneShotFastUs = polledTimeout::timeoutTemplate<false, YieldPolicy::DoNothing, TimePolicy::TimeFastMicros>;
+using periodicFastUs = polledTimeout::timeoutTemplate<true, YieldPolicy::DoNothing, TimePolicy::TimeFastMicros>;
+using oneShotFastNs = polledTimeout::timeoutTemplate<false, YieldPolicy::DoNothing, TimePolicy::TimeFastNanos>;
+using periodicFastNs = polledTimeout::timeoutTemplate<true, YieldPolicy::DoNothing, TimePolicy::TimeFastNanos>;
+
+} //polledTimeout
+
+
+/*  A 1-shot timeout that auto-yields when in CONT can be built as follows:
+    using oneShotYieldMs = esp8266::polledTimeout::timeoutTemplate<false, esp8266::polledTimeout::YieldPolicy::YieldOrSkip>;
+
+    Other policies can be implemented by the user, e.g.: simple yield that panics in SYS, and the polledTimeout types built as needed as shown above, without modifying this file.
+*/
+
+}//esp8266

cores/rp2040/RP2040Support.h

@@ -22,12 +22,13 @@
 #include <hardware/irq.h>
 #include <hardware/pio.h>
 #include <hardware/exception.h>
+#include <hardware/structs/rosc.h>
 #include <hardware/structs/systick.h>
 #include <pico/multicore.h>
 #include <pico/util/queue.h>
 #include "CoreMutex.h"
 #include "ccount.pio.h"
-
+#include <malloc.h>
 
 extern "C" volatile bool __otherCoreIdled;
 
@@ -141,6 +142,9 @@ extern RP2040 rp2040;
 extern "C" void main1();
 class PIOProgram;
 
+extern "C" char __StackLimit;
+extern "C" char __bss_end__;
+
 // Wrapper class for PIO programs, abstracting common operations out
 // TODO - Add unload/destructor
 class PIOProgram {
@@ -257,6 +261,19 @@ class RP2040 {
         }
     }
 
+    inline int getFreeHeap() {
+        return getTotalHeap() - getUsedHeap();
+    }
+
+    inline int getUsedHeap() {
+        struct mallinfo m = mallinfo();
+        return m.uordblks;
+    }
+
+    inline int getTotalHeap() {
+        return &__StackLimit  - &__bss_end__;
+    }
+
     void idleOtherCore() {
         fifo.idleOtherCore();
     }
@@ -274,6 +291,29 @@ class RP2040 {
     // Multicore comms FIFO
     _MFIFO fifo;
 
+
+    // TODO - Not so great HW random generator.  32-bits wide.  Cryptographers somewhere are crying
+    uint32_t hwrand32() {
+        // Try and whiten the HW ROSC bit
+        uint32_t r = 0;
+        for (int k = 0; k < 32; k++) {
+            unsigned long int b;
+            do {
+                b = rosc_hw->randombit & 1;
+                if (b != (rosc_hw->randombit & 1)) {
+                    break;
+                }
+            } while (true);
+            r <<= 1;
+            r |= b;
+        }
+        // Stir using the cycle count LSBs.  In any WiFi use case this will be a random # since the connection time is not cycle-accurate
+        uint64_t rr = (((uint64_t)~r) << 32LL) | r;
+        rr >>= rp2040.getCycleCount() & 32LL;
+
+        return (uint32_t)rr;
+    }
+
 private:
     static void _SystickHandler() {
         rp2040._epoch += 1LL << 24;