C++ SMTP发送邮件（支持SSL，可用于使用QQ邮箱发送）

//////////////////////////////////////////////////////////////////////////////// // Original class CFastSmtp written by // christopher w. backen <immortal@cox.net> // More details at: http://www.codeproject.com/KB/IP/zsmtp.aspx // // Modifications introduced by Jakub Piwowarczyk: // 1. name of the class and functions // 2. new functions added: SendData,ReceiveData and more // 3. authentication added // 4. attachments added // 5 .comments added // 6. DELAY_IN_MS removed (no delay during sending the message) // 7. non-blocking mode // More details at: http://www.codeproject.com/KB/mcpp/CSmtp.aspx //////////////////////////////////////////////////////////////////////////////// //////////////////////////////////////////////////////////////////////////////// // SSL/TLS support added by John Tang by making use of OpenSSL: http://www.openssl.org/ // More details at: http://www.codeproject.com/KB/IP/smtp_ssl.aspx // // PLAIN, CRAM-MD5 and DIGESTMD5 authentication added by David Johns // // Revision History: // - Version 2.4: Updated with fixes reported as of 22 Oct 2015 // > Fixed issues with files being left opened and buffer not being deleted if an error occurs as discussed here: http://www.codeproject.com/Messages/4651730/Re-File-attachment.aspx // - Thanks to Josep Sol� // > Fixed issue with opening attachments as discussed here: http://www.codeproject.com/Messages/4640325/File-path-mistakenly-ommitted-from-file-name-when-.aspx // - Thanks to Graham // > Fixed potential memory leak as discussed here: http://www.codeproject.com/Messages/5010012/Memory-leaks.aspx // - Thanks to LahPo // > Made total message size limit larger as recommended here: http://stackoverflow.com/questions/22426686/csmtp-wont-send-an-e-mail-attachment-but-without-the-attachment-it-works-fine/28333737#28333737 // - Thanks to Stanislav // > Fixed an issue with incomplete attachment file paths as discussed here: http://www.codeproject.com/Messages/5127588/Re-Attachment-does-not-come.aspx // - Thanks to Member 11508846 and Member 11887128 // - Version 2.3: Updated with fixes reported as of 17 Aug 2013 // > Removed Bcc header so that recipients don't see who it was Bcc'd to as discussed here: http://www.codeproject.com/Messages/4633562/Bcc-and-mail-header.aspx // - Thanks to o15s19 // > Fixed problem with attaching files that have unicode or reserved character filenames as discussed here: http://www.codeproject.com/Messages/4610174/Re-About-snprintf-FileName-255-Attachments-FileId-.aspx // - Thanks to uni_gauldoth // > Improved the method used for checking attachment file sizes as discussed here: http://www.codeproject.com/Messages/4562481/retreiving-file-size-for-attachments.aspx // - Thanks to GKarRacer // > Added #include <unistd.h> for linux compiles, which was required for gethostname as discussed here: http://www.codeproject.com/Messages/4551908/Works-on-Linux-CSmtp-cpp-needed-sharpinclude-unist.aspx // - Thanks to jim fred // - Version 2.2: Updated with fixes reported as of 6 May 2013 // > Fixed check on MsgBody.size() as discussed here: http://www.codeproject.com/Messages/4555663/Incorrect-range-check.aspx // - Thanks to GKarRacer // > Moved memory allocation and checking if attachments could be opened to before the MAIL command is // issued to avoid throwing errors in a place where you can't terminate the connection gracefully without // the email being sent corrupted // > Changed all sprintf calls to snprintf to add greater security. #define'd snprintf to sprintf_s for // MSVC. Also changed all strcpy to snprintf since that is the only way to use a secure function that // is portable between standard C and MSVC since MS re-ordered the arguments between strcpy and // strcpy_s // > Fixed issue with SayQuit that could lead to infinite loop discussed here: http://www.codeproject.com/Messages/4451901/exception-in-SayQuit-could-lead-to-infinite-loop.aspx // - Thanks to jcyangzh! // > Fixed issue with AUTH PLAIN implementation discussed here: http://www.codeproject.com/Messages/4433069/looks-like-a-bug-in-plain-auth.aspx // - Thanks to sbrytskyy! // - Version 2.1: Updated with fixes reported as of 26 Mar 2012 // > Fixed issue in main.cpp with referring to USE_TLS in the wrong scope discussed here: http://www.codeproject.com/Messages/4151405/Re-USE_SSL-no-member-of-CSmtp.aspx // - Thanks to Alan P Brown! // > Added modifications to allow it to compile in Debian Linux discussed here: http://www.codeproject.com/Messages/4132697/linux-port-patch.aspx // - Thanks to Oleg Dolgov! // > Added ability to change the character set, inspired by this post: http://www.codeproject.com/Messages/4238701/Re-The-subject-contains-the-Chinese-letters-could-.aspx // - Thanks to LeonHuang0726 and John TWC for the suggestion! // > Added ability to request a read receipt by calling SetReadReceipt as proposed here: http://www.codeproject.com/Messages/3938944/Disposition-Notification-To.aspx // - Thanks to Gospa for the suggestion! // > Added check for Linux when adding paths of attachments in the MIME header as suggested here: http://www.codeproject.com/Messages/4357144/portability-bug-w-attachment-name.aspx // - Thanks to Spike! // > Switched method of setting private std::string variables to use the = operator as suggested here: http://www.codeproject.com/Messages/4356937/portability-bugs-w-std-string-and-exceptions.aspx // - Thanks to Spike! // > Added SetLocalHostName function proposed here: http://www.codeproject.com/Messages/4092347/bug-fixes-GetLocalHostName-Send.aspx // - Thanks to jerko! // > Added the modifications to allow it to compile in Linux described here: http://www.codeproject.com/Messages/3878620/My-vote-of-5.aspx // - Thanks to korisk! // > Added the fix that corrects behavior when m_sNameFrom is empty described here: http://www.codeproject.com/Messages/4196071/Bug-Mail-sent-by-mail-domain-com.aspx // - Thanks to agenua.grupoi68! // - Version 2.0: Updated to all fixes reported as of 23 Jun 2011: // > Added the m_bAuthenticate member variable to be able to disable authentication // even though it may be supported by the server. It defaults to true so if it is // not set the library will act as it would have before the addition. // > Added the ability to pass the security type, m_type, the new m_Authenticate flag, // the login and password into the ConnectRemoteServer function. If these new arguments // are not included in the call the function will work as it did before. // > Added the ability to pass the new m_Authenticate flag into the SetSMTPServer function. // If not provided, the function will act as it would before the addition. // > Added fix described here: http://www.codeproject.com/Messages/3681792/Bug-when-reading-answer.aspx // - Thanks to Martin Kjallman! // > Added fixes described here: http://www.codeproject.com/Messages/3707662/Mistakes.aspx // - Thanks to Karpov Andrey! // > Added fixes described here: http://www.codeproject.com/Messages/3587166/Re-Possible-Solution-To-Misc-EHLO-Errors.aspx // - Thanks to Jakub Piwowarczyk! // - Version 1.9: Started with Revion 6 in code project http://www.codeproject.com/script/Articles/ListVersions.aspx?aid=98355 //////////////////////////////////////////////////////////////////////////////// #include "CSmtp.h" #include "base64.h" #include "openssl/err.h" #include <cassert> #ifndef LINUX //Add "openssl-0.9.8l\out32" to Additional Library Directories #pragma comment(lib, "ssleay32.lib") #pragma comment(lib, "libeay32.lib") #endif Command_Entry command_list[] = { {command_INIT, 0, 5*60, 220, EC