SMTP Client improvements.

Sming/Components/Network/src/Network/MailMessage.cpp

@@ -48,13 +48,11 @@ MailMessage& MailMessage::setBody(String&& body, MimeType mime) noexcept
 
 MailMessage& MailMessage::setBody(IDataSourceStream* stream, MimeType mime)
 {
-	if(this->stream != nullptr) {
+	if(this->stream) {
 		debug_e("MailMessage::setBody: Discarding already set stream!");
-		delete this->stream;
-		this->stream = nullptr;
 	}
 
-	this->stream = stream;
+	this->stream.reset(stream);
 	headers[HTTP_HEADER_CONTENT_TYPE] = toString(mime);
 
 	return *this;

Sming/Components/Network/src/Network/MailMessage.h

@@ -38,6 +38,14 @@ class MailMessage
 	String subject;
 	String cc;
 
+	~MailMessage()
+	{
+		for(auto& attachment : attachments) {
+			delete attachment.headers;
+			delete attachment.stream;
+		}
+	}
+
 	/**
 	 * @brief Set a header value
 	 * @param name
@@ -106,7 +114,7 @@ class MailMessage
 	MailMessage& addAttachment(IDataSourceStream* stream, const String& mime, const String& filename = "");
 
 private:
-	IDataSourceStream* stream = nullptr;
+	std::unique_ptr<IDataSourceStream> stream = nullptr;
 	HttpHeaders headers;
 	Vector<MultipartStream::BodyPart> attachments;
 };

Sming/Components/Network/src/Network/SmtpClient.cpp

@@ -22,6 +22,7 @@
 #include <Data/Stream/Base64OutputStream.h>
 #include <Data/HexString.h>
 #include <Crypto/Md5.h>
+#include <Network/Ssl/Factory.h>
 
 #define ADVANCE                                                                                                        \
 	{                                                                                                                  \
@@ -288,7 +289,7 @@ void SmtpClient::sendMailHeaders(MailMessage* mail)
 
 	if(!mail->headers.contains(HTTP_HEADER_CONTENT_TRANSFER_ENCODING)) {
 		mail->headers[HTTP_HEADER_CONTENT_TRANSFER_ENCODING] = _F("quoted-printable");
-		mail->stream = new QuotedPrintableOutputStream(mail->stream);
+		mail->stream = std::make_unique<QuotedPrintableOutputStream>(mail->stream.release());
 	}
 
 	if(!mail->attachments.isEmpty()) {
@@ -297,13 +298,13 @@ void SmtpClient::sendMailHeaders(MailMessage* mail)
 		text.headers = new HttpHeaders();
 		(*text.headers)[HTTP_HEADER_CONTENT_TYPE] = mail->headers[HTTP_HEADER_CONTENT_TYPE];
 		(*text.headers)[HTTP_HEADER_CONTENT_TRANSFER_ENCODING] = mail->headers[HTTP_HEADER_CONTENT_TRANSFER_ENCODING];
-		text.stream = mail->stream;
+		text.stream = mail->stream.release();
 
 		mail->attachments.insertElementAt(text, 0);
 
 		mail->headers.remove(HTTP_HEADER_CONTENT_TRANSFER_ENCODING);
 		mail->headers[HTTP_HEADER_CONTENT_TYPE] = F("multipart/mixed; boundary=") + mStream->getBoundary();
-		mail->stream = mStream;
+		mail->stream.reset(mStream);
 	}
 
 	for(auto hdr : mail->headers) {
@@ -319,8 +320,7 @@ bool SmtpClient::sendMailBody(MailMessage* mail)
 	}
 
 	delete stream;
-	stream = mail->stream; // avoid intermediate buffers
-	mail->stream = nullptr;
+	stream = mail->stream.release(); // avoid intermediate buffers
 
 	return false;
 }
@@ -390,8 +390,15 @@ int SmtpClient::smtpParse(char* buffer, size_t len)
 			RETURN_ON_ERROR(SMTP_CODE_SERVICE_READY);
 
 			if(!useSsl && (options & SMTP_OPT_STARTTLS)) {
-				useSsl = true;
-				TcpConnection::internalOnConnected(ERR_OK);
+				if(!enableSsl(url.Host)) {
+					/*
+					 * Excerpt from RFC 3207: If,
+					 * after having issued the STARTTLS command, the client finds out that
+					 * some failure prevents it from actually starting a TLS handshake, then
+					 * it SHOULD abort the connection.
+					 */
+					return 0;
+				}
 			}
 
 			sendString(F("EHLO ") + url.Host + "\r\n");
@@ -420,8 +427,16 @@ int SmtpClient::smtpParse(char* buffer, size_t len)
 			if(isLastLine) {
 				state = eSMTP_Ready;
 				if(!useSsl && (options & SMTP_OPT_STARTTLS)) {
-					state = eSMTP_StartTLS;
-				} else if(url.User && authMethods.count()) {
+					if(Ssl::factory != nullptr) {
+						state = eSMTP_StartTLS;
+						break;
+					}
+
+					bitClear(options, SMTP_OPT_STARTTLS);
+					debug_w("[SMTP] SSL required, no factory. Continue plain-text communication.");
+				}
+
+				if(url.User && authMethods.count()) {
 					state = eSMTP_SendAuth;
 				}
 			}

Sming/Components/Network/src/Network/TcpConnection.cpp

@@ -423,6 +423,29 @@ err_t TcpConnection::internalOnConnected(err_t err)
 	return res;
 }
 
+bool TcpConnection::enableSsl(const String& hostName)
+{
+	if(tcp == nullptr) {
+		return false;
+	}
+
+	if(tcp->state != ESTABLISHED) {
+		return false;
+	}
+
+	if(!sslCreateSession()) {
+		return false;
+	}
+
+	ssl->hostName = hostName;
+
+	useSsl = true;
+	if(internalOnConnected(ERR_OK) != ERR_OK) {
+		useSsl = false;
+	}
+	return useSsl;
+}
+
 err_t TcpConnection::internalOnReceive(pbuf* p, err_t err)
 {
 	sleep = 0;

Sming/Components/Network/src/Network/TcpConnection.h

@@ -154,6 +154,13 @@ class TcpConnection : public IpConnection
 		return ssl;
 	}
 
+	/**
+	 * @brief Enables Secure Socket Layer on the current connection
+	 * @param hostName
+	 * @retval true on success, false otherwise
+	 */
+	bool enableSsl(const String& hostName = nullptr);
+
 protected:
 	void initialize(tcp_pcb* pcb);
 	bool internalConnect(IpAddress addr, uint16_t port);

Sming/Components/Network/src/Network/Url.cpp

@@ -86,6 +86,8 @@ String Url::toString() const
 			result += ':';
 			result += Password;
 		}
+
+		result += '@';
 	}
 
 	result += getHostWithPort();

samples/SmtpClient/app/application.cpp

@@ -24,7 +24,7 @@ int onServerError(SmtpClient& client, int code, char* status)
 {
 	debugf("Status: %s", status);
 
-	return 0; // return non-zero value to abort the connection
+	return -1; // return non-zero value to abort the connection
 }
 
 int onMailSent(SmtpClient& client, int code, char* status)