feat(hash): Add hashing library and SHA3 algorithm

Author: lucasssvaz

CMakeLists.txt

@@ -54,15 +54,15 @@ set(CORE_SRCS
   cores/esp32/freertos_stats.cpp
   cores/esp32/FunctionalInterrupt.cpp
   cores/esp32/HardwareSerial.cpp
-  cores/esp32/HEXBuilder.cpp
+  cores/esp32/HashBuilder.cpp
+  cores/esp32/HexBuilder.cpp
   cores/esp32/IPAddress.cpp
   cores/esp32/libb64/cdecode.c
   cores/esp32/libb64/cencode.c
   cores/esp32/MacAddress.cpp
   cores/esp32/main.cpp
   cores/esp32/MD5Builder.cpp
   cores/esp32/Print.cpp
-  cores/esp32/SHA1Builder.cpp
   cores/esp32/stdlib_noniso.c
   cores/esp32/Stream.cpp
   cores/esp32/StreamString.cpp
@@ -93,6 +93,7 @@ set(ARDUINO_ALL_LIBRARIES
   Ethernet
   FFat
   FS
+  Hash
   HTTPClient
   HTTPUpdate
   Insights
@@ -154,6 +155,11 @@ set(ARDUINO_LIBRARY_FS_SRCS
   libraries/FS/src/FS.cpp
   libraries/FS/src/vfs_api.cpp)
 
+set(ARDUINO_LIBRARY_Hash_SRCS
+  libraries/Hash/src/SHA1Builder.cpp
+  libraries/Hash/src/SHA3Builder.cpp
+  )
+
 set(ARDUINO_LIBRARY_HTTPClient_SRCS libraries/HTTPClient/src/HTTPClient.cpp)
 
 set(ARDUINO_LIBRARY_HTTPUpdate_SRCS libraries/HTTPUpdate/src/HTTPUpdate.cpp)

cores/esp32/HashBuilder.cpp

@@ -0,0 +1,38 @@
+// Copyright 2025 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "HashBuilder.h"
+
+void HashBuilder::add(const char *data) {
+  add((const uint8_t *)data, strlen(data));
+}
+
+void HashBuilder::add(String data) {
+  add(data.c_str());
+}
+
+void HashBuilder::addHexString(const char *data) {
+  size_t len = strlen(data);
+  uint8_t *tmp = (uint8_t *)malloc(len / 2);
+  if (tmp == NULL) {
+    return;
+  }
+  hex2bytes(tmp, len / 2, data);
+  add(tmp, len / 2);
+  free(tmp);
+}
+
+void HashBuilder::addHexString(String data) {
+  addHexString(data.c_str());
+}

cores/esp32/HashBuilder.h

@@ -18,25 +18,21 @@
 #include <WString.h>
 #include <Stream.h>
 
-#include "HEXBuilder.h"
+#include "HexBuilder.h"
 
-class HashBuilder : public HEXBuilder {
+// Base class for hash builders
+
+class HashBuilder : public HexBuilder {
 public:
   virtual ~HashBuilder() {}
   virtual void begin() = 0;
 
   virtual void add(const uint8_t *data, size_t len) = 0;
-  virtual void add(const char *data) {
-    add((const uint8_t *)data, strlen(data));
-  }
-  virtual void add(String data) {
-    add(data.c_str());
-  }
-
-  virtual void addHexString(const char *data) = 0;
-  virtual void addHexString(String data) {
-    addHexString(data.c_str());
-  }
+  void add(const char *data);
+  void add(String data);
+
+  void addHexString(const char *data);
+  void addHexString(String data);
 
   virtual bool addStream(Stream &stream, const size_t maxLen) = 0;
   virtual void calculate() = 0;

cores/esp32/HEXBuilder.cpp renamed to cores/esp32/HexBuilder.cpp

@@ -17,8 +17,7 @@
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
 
-#include <Arduino.h>
-#include <HEXBuilder.h>
+#include "HexBuilder.h"
 
 static uint8_t hex_char_to_byte(uint8_t c) {
   return (c >= 'a' && c <= 'f')   ? (c - ((uint8_t)'a' - 0xa))
@@ -27,11 +26,11 @@ static uint8_t hex_char_to_byte(uint8_t c) {
                                   : 0x10;  // unknown char is 16
 }
 
-size_t HEXBuilder::hex2bytes(unsigned char *out, size_t maxlen, String &in) {
+size_t HexBuilder::hex2bytes(unsigned char *out, size_t maxlen, String &in) {
   return hex2bytes(out, maxlen, in.c_str());
 }
 
-size_t HEXBuilder::hex2bytes(unsigned char *out, size_t maxlen, const char *in) {
+size_t HexBuilder::hex2bytes(unsigned char *out, size_t maxlen, const char *in) {
   size_t len = 0;
   for (; *in; in++) {
     uint8_t c = hex_char_to_byte(*in);
@@ -54,7 +53,7 @@ size_t HEXBuilder::hex2bytes(unsigned char *out, size_t maxlen, const char *in)
   return (len + 1) / 2;
 }
 
-size_t HEXBuilder::bytes2hex(char *out, size_t maxlen, const unsigned char *in, size_t len) {
+size_t HexBuilder::bytes2hex(char *out, size_t maxlen, const unsigned char *in, size_t len) {
   for (size_t i = 0; i < len; i++) {
     if (i * 2 + 1 < maxlen) {
       sprintf(out + (i * 2), "%02x", in[i]);
@@ -63,7 +62,7 @@ size_t HEXBuilder::bytes2hex(char *out, size_t maxlen, const unsigned char *in,
   return len * 2 + 1;
 }
 
-String HEXBuilder::bytes2hex(const unsigned char *in, size_t len) {
+String HexBuilder::bytes2hex(const unsigned char *in, size_t len) {
   size_t maxlen = len * 2 + 1;
   char *out = (char *)malloc(maxlen);
   if (!out) {

cores/esp32/HEXBuilder.h renamed to cores/esp32/HexBuilder.h

@@ -17,13 +17,15 @@
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
 
-#ifndef HEXBuilder_h
-#define HEXBuilder_h
+#ifndef HexBuilder_h
+#define HexBuilder_h
 
 #include <WString.h>
 #include <Stream.h>
 
-class HEXBuilder {
+// Basic hex/byte conversion class to be used by hash builders
+
+class HexBuilder {
 public:
   static size_t hex2bytes(unsigned char *out, size_t maxlen, String &in);
   static size_t hex2bytes(unsigned char *out, size_t maxlen, const char *in);

cores/esp32/MD5Builder.cpp

@@ -17,9 +17,8 @@
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
 
-#include <Arduino.h>
-#include <HEXBuilder.h>
-#include <MD5Builder.h>
+#include "HexBuilder.h"
+#include "MD5Builder.h"
 
 void MD5Builder::begin(void) {
   memset(_buf, 0x00, ESP_ROM_MD5_DIGEST_LEN);
@@ -30,17 +29,6 @@ void MD5Builder::add(const uint8_t *data, size_t len) {
   esp_rom_md5_update(&_ctx, data, len);
 }
 
-void MD5Builder::addHexString(const char *data) {
-  size_t len = strlen(data);
-  uint8_t *tmp = (uint8_t *)malloc(len / 2);
-  if (tmp == NULL) {
-    return;
-  }
-  hex2bytes(tmp, len / 2, data);
-  add(tmp, len / 2);
-  free(tmp);
-}
-
 bool MD5Builder::addStream(Stream &stream, const size_t maxLen) {
   const int buf_size = 512;
   int maxLengthLeft = maxLen;

cores/esp32/MD5Builder.h

@@ -35,14 +35,10 @@ class MD5Builder : public HashBuilder {
   uint8_t _buf[ESP_ROM_MD5_DIGEST_LEN];
 
 public:
-  void begin(void) override;
-
   using HashBuilder::add;
-  void add(const uint8_t *data, size_t len) override;
-
-  using HashBuilder::addHexString;
-  void addHexString(const char *data) override;
 
+  void begin(void) override;
+  void add(const uint8_t *data, size_t len) override;
   bool addStream(Stream &stream, const size_t maxLen) override;
   void calculate(void) override;
   void getBytes(uint8_t *output) override;

libraries/ESP32/examples/Utilities/HEXBuilder/HEXBuilder.ino renamed to libraries/Hash/examples/Hex/Hex.ino

@@ -1,4 +1,10 @@
-#include <HEXBuilder.h>
+/*
+  Usage example for the HexBuilder class.
+
+  This example shows how to convert a HEX string to a binary buffer and vice versa.
+*/
+
+#include <HexBuilder.h>
 
 void setup() {
   Serial.begin(115200);
@@ -11,7 +17,7 @@ void setup() {
     const char *hexin = "48656c6c6f20576f726c6400";  // As the string above is \0 terminated too
 
     unsigned char buff[256];
-    size_t len = HEXBuilder::hex2bytes(buff, sizeof(buff), hexin);
+    size_t len = HexBuilder::hex2bytes(buff, sizeof(buff), hexin);
 
     if (len != 1 + strlen(out)) {
       Serial.println("Odd - length 1 is wrong");
@@ -30,7 +36,7 @@ void setup() {
     const char hello[] = "Hello World";
 
     unsigned char buff[256];
-    size_t len = HEXBuilder::hex2bytes(buff, sizeof(buff), helloHEX);
+    size_t len = HexBuilder::hex2bytes(buff, sizeof(buff), helloHEX);
 
     if (len != strlen(hello)) {
       Serial.println("Odd - length 2 is wrong");
@@ -45,7 +51,7 @@ void setup() {
     const unsigned char helloBytes[] = {0x48, 0x56, 0x6c, 0x6c, 0x6f, 0x20, 0x57, 0x6f, 0x72, 0x6c, 0x64};
     String helloHEX = "48566c6c6f20576f726c64";
 
-    String out = HEXBuilder::bytes2hex(helloBytes, sizeof(helloBytes));
+    String out = HexBuilder::bytes2hex(helloBytes, sizeof(helloBytes));
     if (out.length() != 2 * sizeof(helloBytes)) {
       Serial.println("Odd - length 3 is wrong");
     }
@@ -61,7 +67,7 @@ void setup() {
     const char helloHex[] = "6c6c6f20576f726c64";
 
     char buff[256];
-    size_t len = HEXBuilder::bytes2hex(buff, sizeof(buff), helloBytes, sizeof(helloBytes));
+    size_t len = HexBuilder::bytes2hex(buff, sizeof(buff), helloBytes, sizeof(helloBytes));
     if (len != 1 + 2 * sizeof(helloBytes)) {
       Serial.println("Odd - length 4 is wrong");
     }