Allow manually setting MD5 checksum for HTTP update (#8204)

Author: vlastahajek

libraries/ESP8266httpUpdate/src/ESP8266httpUpdate.cpp

@@ -211,8 +211,14 @@ HTTPUpdateResult ESP8266HTTPUpdate::handleUpdate(HTTPClient& http, const String&
     DEBUG_HTTP_UPDATE("[httpUpdate]  - code: %d\n", code);
     DEBUG_HTTP_UPDATE("[httpUpdate]  - len: %d\n", len);
 
-    if(http.hasHeader("x-MD5")) {
-        DEBUG_HTTP_UPDATE("[httpUpdate]  - MD5: %s\n", http.header("x-MD5").c_str());
+    String md5;
+    if (_md5Sum.length()) {
+        md5 = _md5Sum; 
+    } else if(http.hasHeader("x-MD5")) {
+        md5 = http.header("x-MD5");
+    }
+    if(md5.length()) {
+        DEBUG_HTTP_UPDATE("[httpUpdate]  - MD5: %s\n", md5.c_str());
     }
 
     DEBUG_HTTP_UPDATE("[httpUpdate] ESP8266 info:\n");
@@ -298,7 +304,7 @@ HTTPUpdateResult ESP8266HTTPUpdate::handleUpdate(HTTPClient& http, const String&
                         }
                     }
                 }
-                if(runUpdate(*tcp, len, http.header("x-MD5"), command)) {
+                if(runUpdate(*tcp, len, md5, command)) {
                     ret = HTTP_UPDATE_OK;
                     DEBUG_HTTP_UPDATE("[httpUpdate] Update ok\n");
                     http.end();

libraries/ESP8266httpUpdate/src/ESP8266httpUpdate.h

@@ -108,6 +108,11 @@ class ESP8266HTTPUpdate
         _ledOn = ledOn;
     }
 
+    void setMD5sum(const String &md5Sum) 
+    {
+        _md5Sum = md5Sum;
+    }
+
     void setAuthorization(const String& user, const String& password);
     void setAuthorization(const String& auth);
 
@@ -142,7 +147,7 @@ class ESP8266HTTPUpdate
     String _user;
     String _password;
     String _auth;
-
+    String _md5Sum;
 private:
     int _httpClientTimeout;
     followRedirects_t _followRedirects = HTTPC_DISABLE_FOLLOW_REDIRECTS;