前言
c++实现smtp发送邮件，支持ssl的465端口发送，支持附件、一次发送多人、抄送等。
这里只使用了openssl库（用来支持ssl的465端口），其他部分是原生c++,支持在win/linux运行。
网上很多都是原始的支持25端口，明文发送，这里介绍一下ssl思路
实现思路
使用sockect编程和ssl，使用SMTP协议。
使用了c++的多态语言特性，包括重载和虚函数。
文中给出mail.h 和mail.cpp 以及main.cpp部分测试代码
Linux安装openssl
sudo apt install libssl-dev
win下自行下载安装
SMTP协议简介
SMTP协议的定义：
1、SMTP 是一种TCP协议支持的提供可靠且有效电子邮件传输的应用层协议；
2、SMTP 是建立在 TCP上的一种邮件服务，主要用于传输系统之间的邮件信息并提供来信有关的通知；
3、SMTP 独立于特定的传输子系统，且只需要可靠有序的数据流信道支持；
4、SMTP 重要特性之一是其能跨越网络传输邮件，即“ SMTP 邮件中继”；
5、SMTP是一个相对简单的基于文本的协议。
SMTP基本命令
SMTP基本命令包括以下几个：HELO﹑EHLO、MAIL﹑RCPT﹑DATA、AUTH LOGIN和QUIT
1、HELO–发件方问候收件方，后面是发件人的服务器地址或标识。收件方回答OK时标识自己的身份。问候和确认过程表明两台机器可以进行通信，同时状态参量被复位，缓冲区被清空。
EHLO–申明身份，表示自己身份需要验证，注意这部分需要通过Telnet验证一下，是user@example.com还是user，否则会出错。
2、MAIL–这个命令用来开始传送邮件，它的后面跟随发件方邮件地址（返回邮件地址）。它也用来当邮件无法送达时，发送失败通知。为保证邮件的成功发送，发件方的地址应是被对方或中间转发方同意接受的。这个命令会清空有关的缓冲区，为新的邮件做准备。
3、RCPT –这个命令告诉收件方收件人的邮箱。当有多个收件人时，需要多次使用该命令RCPT
4、TO，每次只能指明一个人。如果接收方服务器不同意转发这个地址的邮件，它必须报550错误代码通知发件方。如果服务器同意转发，它要更改邮件发送路径，把最开始的目的地（该服务器）换成下一个服务器。
5、DATA–收件方把该命令之后的数据作为发送的数据。数据被加入数据缓冲区中，以单独一行是”.”的行结束数据。结束行对于接收方同时意味立即开始缓冲区内的数据传送，传送结束后清空缓冲区。如果传送接受，接收方回复OK。
6、QUIT–SMTP要求接收放必须回答OK，然后中断传输；在收到这个命令并回答OK前，收件方不得中断连接，即使传输出现错误。发件方在发出这个命令并收到OK答复前，也不得中断连接。
7、AUTH LOGIN–登录邮箱，这一部分一般要用base64加密。
头文件mail.h
#pragma once
#include <string>
#include <vector>
#include <map>
#include <openssl/ossl_typ.h>
#ifndef WIN32
#include<netdb.h>
#endif
class SmtpBase
{
protected:
struct EmailInfo
{
std::string smtpServer; //the SMTP server
std::string serverPort; //the SMTP server port
std::string charset; //the email character set
std::string sender; //the sender's name
std::string senderEmail; //the sender's email
std::string password; //the password of sender
std::string recipient; //the recipient's name
std::string recipientEmail; //the recipient's email
std::map<std::string, std::string> recvList; //收件人列表<email, name>
std::string subject; //the email message's subject 邮件主题
std::string message; //the email message body 邮件内容
std::map<std::string, std::string> ccEmail; //抄送列表
std::vector<std::string> attachment; //附件
};
public:
virtual ~SmtpBase() {}
/**
* @brief 简单发送文本邮件
* @param from 发送者的帐号
* @param passs 发送者密码
* @param to 收件人
* @param subject 主题
* @param strMessage 邮件内容
*/
virtual int SendEmail(const std::string& from, const std::string& passs, const std::string& to, const std::string& subject, const std::string& strMessage) = 0;
/**
* @brief 发送邮件，包括附件以及抄送人和多个收件人
* @param from 发送者的帐号
* @param passs 发送者密码
* @param vecTo 收件人列表
* @param subject 主题
* @param strMessage 邮件内容
* @param attachment 附件列表 附件可以是绝对路径，默认是可执行程序目录下
* @param ccList 抄送列表
*/
virtual int SendEmail(const std::string& from, const std::string& passs, const std::vector<std::string>& vecTo,
const std::string& subject, const std::string& strMessage, const std::vector<std::string>& attachment,const std::vector<std::string>& ccList) = 0;
std::string GetLastError()
{
return m_lastErrorMsg;
}
virtual int Read(void* buf, int num) = 0;
virtual int Write(const void* buf, int num) = 0;
virtual int Connect() = 0;
virtual int DisConnect() = 0;
protected:
std::string m_lastErrorMsg;
};
class SmtpEmail : public SmtpBase
{
public:
SmtpEmail(const std::string& emailHost, const std::string& port);
~SmtpEmail();
int SendEmail(const std::string& from, const std::string& passs, const std::string& to, const std::string& subject, const std::string& strMessage);
int SendEmail(const std::string& from, const std::string& passs, const std::vector<std::string>& vecTo,
const std::string& subject, const std::string& strMessage, const std::vector<std::string>& attachment, const std::vector<std::string>& ccList);
protected:
int Read(void* buf, int num);
int Write(const void* buf, int num);
int Connect();
int DisConnect();
virtual std::string GetEmailBody(const EmailInfo & info);
private:
//int SMTPSSLComunicate(SSL *connection, const EmailInfo &info);
int SMTPComunicate(const EmailInfo &info);
protected:
addrinfo* m_addrinfo;
int m_socketfd;
std::string m_host;
std::string m_port;
bool m_isConnected;
};
class SimpleSmtpEmail : public SmtpEmail
{
public:
using SmtpEmail::SmtpEmail;
virtual std::string GetEmailBody(const EmailInfo & info);
};
class SslSmtpEmail : public SmtpEmail
{
public:
using SmtpEmail::SmtpEmail;
~SslSmtpEmail();
int Connect();
int DisConnect();
protected:
int Read(void* buf, int num);
int Write(const void* buf, int num);
private:
SSL_CTX *m_ctx;
SSL *m_ssl;
};
class SimpleSslSmtpEmail : public SslSmtpEmail
{
public:
using SslSmtpEmail::SslSmtpEmail;
virtual std::string GetEmailBody(const EmailInfo & info);
};
实现文件mail.cpp
#ifdef WIN32
#include <WinSock2.h>
#endif
#include "mail.h"
#include <fstream>
#include <sstream>
#include <iostream>
#include <string.h>
#include <openssl/err.h>
#include <openssl/ssl.h>
#ifdef WIN32
#include <WinSock2.h>
#include <WS2tcpip.h>
#pragma comment(lib, "ws2_32.lib")
#else
#include <unistd.h>
#include <arpa/inet.h>
#include <sys/types.h> /* See NOTES */
#include <sys/socket.h>
#define INVALID_SOCKET -1
#endif
template<typename T>
std::string join(T& vecData, const std::string& delim)
{
if (vecData.size() <= 0)
{
return std::string();
}
std::stringstream ss;
for (auto& item : vecData)
{
ss << delim << item ;
}
return ss.str().substr(delim.length());
}
const char MimeTypes[][2][128] =
{
{ "***", "application/octet-stream" },
{ "csv", "text/csv" },
{ "tsv", "text/tab-separated-values" },
{ "tab", "text/tab-separated-values" },
{ "html", "text/html" },
{ "htm", "text/html" },
{ "doc", "application/msword" },
{ "docx", "application/vnd.openxmlformats-officedocument.wordprocessingml.document" },
{ "ods", "application/x-vnd.oasis.opendocument.spreadsheet" },
{ "odt", "application/vnd.oasis.opendocument.text" },
{ "rtf", "application/rtf" },
{ "sxw", "application/vnd.sun.xml.writer" },
{ "txt", "text/plain" },
{ "xls", "application/vnd.ms-excel" },
{ "xlsx", "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" },
{ "pdf", "application/pdf" },
{ "ppt", "application/vnd.ms-powerpoint" },
{ "pps", "application/vnd.ms-powerpoint" },
{ "pptx", "application/vnd.openxmlformats-officedocument.presentationml.presentation" },
{ "wmf", "image/x-wmf" },
{ "atom", "application/atom+xml" },
{ "xml", "application/xml" },
{ "json", "application/json" },
{ "js", "application/javascript" },
{ "ogg", "application/ogg" },
{ "ps", "application/postscript" },
{ "woff", "application/x-woff" },
{ "xhtml","application/xhtml+xml" },
{ "xht", "application/xhtml+xml" },
{ "zip", "application/zip" },
{ "gz", "application/x-gzip" },
{ "rar", "application/rar" },
{ "rm", "application/vnd.rn-realmedia" },
{ "rmvb", "application/vnd.rn-realmedia-vbr" },
{ "swf", "application/x-shockwave-flash" },
{ "au", "audio/basic" },
{ "snd", "audio/basic" },
{ "mid", "audio/mid" },
{ "rmi", "audio/mid" },
{ "mp3", "audio/mpeg" },
{ "aif", "audio/x-aiff" },
{ "aifc", "audio/x-aiff" },
{ "aiff", "audio/x-aiff" },
{ "m3u", "audio/x-mpegurl" },
{ "ra", "audio/vnd.rn-realaudio" },
{ "ram", "audio/vnd.rn-realaudio" },
{ "wav", "audio/x-wave" },
{ "wma", "audio/x-ms-wma" },
{ "m4a", "audio/x-m4a" },
{ "bmp", "image/bmp" },
{ "gif", "image/gif" },
{ "jpe", "image/jpeg" },
{ "jpeg", "image/jpeg" },
{ "jpg", "image/jpeg" },
{ "jfif", "image/jpeg" },
{ "png", "image/png" },
{ "svg", "image/svg+xml" },
{ "tif", "image/tiff" },
{ "tiff", "image/tiff" },
{ "ico", "image/vnd.microsoft.icon" },
{ "css", "text/css" },
{ "bas", "text/plain" },
{ "c", "text/plain" },
{ "h", "text/plain" },
{ "rtx", "text/richtext" },
{ "mp2", "video/mpeg" },
{ "mpa", "video/mpeg" },
{ "mpe", "video/mpeg" },
{ "mpeg", "video/mpeg" },
{ "mpg", "video/mpeg" },
{ "mpv2", "video/mpeg" },
{ "mov", "video/quicktime" },
{ "qt", "video/quicktime" },
{ "lsf", "video/x-la-asf" },
{ "lsx", "video/x-la-asf" },
{ "asf", "video/x-ms-asf" },
{ "asr", "video/x-ms-asf" },
{ "asx", "video/x-ms-asf" },
{ "avi", "video/x-msvideo" },
{ "3gp", "video/3gpp" },
{ "3gpp", "video/3gpp" },
{ "3g2", "video/3gpp2" },
{ "movie","video/x-sgi-movie" },
{ "mp4", "video/mp4" },
{ "wmv", "video/x-ms-wmv" },
{ "webm","video/webm" },
{ "m4v", "video/x-m4v" },
{ "flv", "video/x-flv" }
};
std::string fileBasename(const std::string path)
{
std::string filename = path.substr(path.find_last_of("/\\") + 1);//解析出文件名字
return filename;
}
std::string getFileContents(const char *filename)
{
std::ifstream in(filename, std::ios::in | std::ios::binary);
if (in)
{
std::string contents;
in.seekg(0, std::ios::end);
contents.resize(in.tellg());
in.seekg(0, std::ios::beg);
in.read(&contents[0], contents.size());
in.close();
return(contents);
}
else {
printf("文件读取失败:%s\n",filename);
return "";
}
}
//获取文件的后缀名 如xxx.jpg 获取的是jpg
std::string GetFileExtension(const std::string& FileName)
{
if (FileName.find_last_of(".") != std::string::npos) //find_last_of逆向查找在原字符串中最后一个与指定字符串（或字符）中的某个字符匹配的字符，返回它的位置。若查找失败，则返回npos。
return FileName.substr(FileName.find_last_of(".") + 1);
return "";
}
const char* GetMimeTypeFromFileName(char* szFileExt)
{
for (unsigned int i = 0; i < sizeof(MimeTypes) / sizeof(MimeTypes[0]); i++)
{
if (strcmp(MimeTypes[i][0], szFileExt) == 0)
{
return MimeTypes[i][1];
}
}
return MimeTypes[0][1]; //if does not match any, "application/octet-stream" is returned
}
char* base64Encode(char const* origSigned, unsigned origLength)
{
static const char base64Char[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
unsigned char const* orig = (unsigned char const*)origSigned; // in case any input bytes have the MSB set
if (orig == NULL) return NULL;
unsigned const numOrig24BitValues = origLength / 3;
bool havePadding = origLength > numOrig24BitValues * 3;
bool havePadding2 = origLength == numOrig24BitValues * 3 + 2;
unsigned const numResultBytes = 4 * (numOrig24BitValues + havePadding);
char* result = new char[numResultBytes + 3]; // allow for trailing '/0'
// Map each full group of 3 input bytes into 4 output base-64 characters:
unsigned i;
for (i = 0; i < numOrig24BitValues; ++i)
{
result[4 * i + 0] = base64Char[(orig[3 * i] >> 2) & 0x3F];
result[4 * i + 1] = base64Char[(((orig[3 * i] & 0x3) << 4) | (orig[3 * i + 1] >> 4)) & 0x3F];
result[4 * i + 2] = base64Char[((orig[3 * i + 1] << 2) | (orig[3 * i + 2] >> 6)) & 0x3F];
result[4 * i + 3] = base64Char[orig[3 * i + 2] & 0x3F];
}
// Now, take padding into account. (Note: i == numOrig24BitValues)
if (havePadding)
{
result[4 * i + 0] = base64Char[(orig[3 * i] >> 2) & 0x3F];
if (havePadding2)
{
result[4 * i + 1] = base64Char[(((orig[3 * i] & 0x3) << 4) | (orig[3 * i + 1] >> 4)) & 0x3F];
result[4 * i + 2] = base64Char[(orig[3 * i + 1] << 2) & 0x3F];
}
else
{
result[4 * i + 1] = base64Char[((orig[3 * i] & 0x3) << 4) & 0x3F];
result[4 * i + 2] = '=';
}
result[4 * i + 3] = '=';
}
result[numResultBytes] = '\0';
return result;
}
int SmtpEmail::SMTPComunicate(const EmailInfo &info)
{
if (Connect() != 0)
{
return -1;
}
char * buffer = new char[1000];
memset(buffer, 0, 1000);
Read(buffer, 999);
if (strncmp(buffer, "220", 3) != 0) // not equal to 220
{
m_lastErrorMsg = buffer;
return 220;
}
//向服务器发送ehlo
std::string command = "ehlo EmailService\r\n";
Write(command.c_str(), command.length());
memset(buffer, 0, 1000);
Read(buffer, 999);
if (strncmp(buffer, "250", 3) != 0) // ehlo failed
{
m_lastErrorMsg = buffer;
return 250;
}
//进行登录验证
command = "AUTH PLAIN ";
std::string auth = '\0' + info.senderEmail + '\0' + info.password;
command += base64Encode(auth.data(), auth.size());
command += "\r\n";
Write(command.c_str(), command.length());
memset(buffer, 0, 1000);
Read(buffer, 999);
if (strncmp(buffer, "235", 3) != 0) // login failed
{
m_lastErrorMsg = buffer;
return 250;
}
//设置邮件发送者的邮箱地址
command = "mail FROM:<" + info.senderEmail + ">\r\n";
Write( command.c_str(), command.length());
memset(buffer, 0, 1000);
Read(buffer, 999);
if (strncmp(buffer, "250", 3) != 0) // not ok
{
m_lastErrorMsg = buffer;
return 250;
}
//设置邮件接收者的邮箱地址
command = "RCPT TO:<" + info.recipientEmail + ">\r\n";
Write( command.c_str(), command.length());
memset(buffer, 0, 1000);
Read( buffer, 999);
if (strncmp(buffer, "250", 3) != 0) // not ok
{
m_lastErrorMsg = buffer;
return 250;
}
//准备发送邮件
command = "data\r\n";
Write( command.c_str(), command.length());
memset(buffer, 0, 1000);
Read( buffer, 999);
if (strncmp(buffer, "354", 3) != 0) // not ready to receive message
{
m_lastErrorMsg = buffer;
return 354;
}
command = std::move(GetEmailBody(info));
Write( command.c_str(), command.length());
memset(buffer, 0, 1000);
Read(buffer, 999);
if (strncmp(buffer, "250", 3) != 0) // not ok
{
m_lastErrorMsg = buffer;
return 250;
}
//结束发送过程
delete buffer;
Write( "quit\r\n", 6);
DisConnect();
return 0;
}
std::string SmtpEmail::GetEmailBody(const EmailInfo &info)
{
//设定邮件的发送者名称、接收者名称、邮件主题，邮件内容。
std::ostringstream message;
message << "From: =?" << info.charset << "?b?" << base64Encode(info.sender.c_str(), info.sender.length()) << "?= <" << info.senderEmail << ">\r\n";
std::vector<std::string> vecToList;
for (auto item : info.recvList)
{
std::string to = "=?" + info.charset + "?b?" + base64Encode(item.second.c_str(), item.second.length()) + "?= <" + item.first + ">";
vecToList.push_back(to);
}
message << "To: " << join(vecToList, ",") << "\r\n";
message << "Subject: =?" << info.charset << "?b?" << base64Encode(info.subject.c_str(), info.subject.length()) << "?=\r\n";
message << "MIME-Version: 1.0\r\n";
if (info.ccEmail.size() > 0)
{
std::vector<std::string> vecCcList;
for (auto item : info.ccEmail)
{
std::string cc = "=?" + info.charset + "?b?" + base64Encode(item.first.c_str(), item.first.length()) + "?= <" + item.second + ">";
vecCcList.push_back(cc);
}
message << "Cc:" << join(vecCcList, ",") << "\r\n";
}
message << "Content-Type:multipart/mixed; boundary=\"Separator_ztq_000\"\r\n\r\n";
message << "--Separator_ztq_000\r\n";
message << "Content-Type: multipart/alternative; boundary=\"Separator_ztq_111\"\r\n\r\n";
message << "--Separator_ztq_111\r\n";
message << "Content-Type: " << "text/plain" << "; charset=\"" << info.charset << "\"\r\n";
message << "Content-Transfer-Encoding: base64\r\n";
message << "\r\n"; //此处要加，不然邮件正文无内容
message << base64Encode(info.message.c_str(), info.message.length());
message << "\r\n\r\n";
message << "--Separator_ztq_111--\r\n";
//---------------------文件部分处理--------------------------------------
for (auto item : info.attachment)
{
std::string filename = fileBasename(item);
std::string strContext = getFileContents(item.c_str());
if(strContext.empty())
{
std::cerr << "请检查传入的文件路径是否正确,此路径文件添加到附件失败，不发送此文件:" << std::endl;
std::cerr << item << std::endl;
}
else
{
std::string fileContext = base64Encode(strContext.c_str(), strContext.length());
std::string extension = GetFileExtension(filename);
std::string mimetype = GetMimeTypeFromFileName((char*)extension.c_str());
message << "--Separator_ztq_000\r\n";
message << "Content-Type: " << mimetype << "; name=\"" << filename << "\"\r\n";
message << "Content-Transfer-Encoding: base64\r\n";
message << "Content-Disposition: attachment; filename=\"" << filename << "\"\r\n\r\n";
message << fileContext + "\r\n\r\n"; //把读取到的文件内容以二进制形式发送
}
}
//-----------------------------------------------------------
message << "\r\n.\r\n";
return message.str();
}
SmtpEmail::SmtpEmail(const std::string& emailHost, const std::string& port) :m_host(emailHost), m_port(port)
{
}
SmtpEmail::~SmtpEmail()
{
}
int SmtpEmail::Read(void* buf, int num)
{
return recv(m_socketfd, (char*)buf, num, 0);
}
int SmtpEmail::Write(const void* buf, int num)
{
return send(m_socketfd, (char*)buf, num, 0);
}
int SmtpEmail::Connect()
{
#ifdef WIN32
//start socket connection
WSADATA wsadata;
WSAStartup(MAKEWORD(2, 2), &wsadata);
#endif
m_socketfd = socket(AF_INET, SOCK_STREAM, 0);
if (m_socketfd == INVALID_SOCKET)
{
m_lastErrorMsg = "Error on creating socket fd.";
return -1;
}
addrinfo inAddrInfo = { 0 };
inAddrInfo.ai_family = AF_INET;
inAddrInfo.ai_socktype = SOCK_STREAM;
printf("host:%s port:%s \n",m_host.c_str(), m_port.c_str());
if (getaddrinfo(m_host.c_str(), m_port.c_str(), &inAddrInfo, &m_addrinfo) != 0) // error occurs
{
m_lastErrorMsg = "Error on calling getadrrinfo().";
return -2;
}
if (connect(m_socketfd, m_addrinfo->ai_addr, m_addrinfo->ai_addrlen))
{
m_lastErrorMsg = "Error on calling connect().";
return -3;
}
return 0;
}
int SmtpEmail::DisConnect()
{
freeaddrinfo(m_addrinfo);
#ifdef WIN32
closesocket(m_socketfd);
#else
close(m_socketfd);
#endif
return 0;
}
/*********************************************************************************/
std::string SimpleSmtpEmail::GetEmailBody(const EmailInfo &info)
{
//设定邮件的发送者名称、接收者名称、邮件主题，邮件内容。
std::ostringstream message;
message << "From: =?" << info.charset << "?b?" << base64Encode(info.sender.c_str(), info.sender.length()) << "?= <" << info.senderEmail << ">\r\n";
std::vector<std::string> vecToList;
for (auto item : info.recvList)
{
std::string to = "=?" + info.charset + "?b?" + base64Encode(item.second.c_str(), item.second.length()) + "?= <" + item.first + ">";
vecToList.push_back(to);
}
message << "To: " << join(vecToList, ",") << "\r\n";
message << "Subject: =?" << info.charset << "?b?" << base64Encode(info.subject.c_str(), info.subject.length()) << "?=\r\n";
message << "MIME-Version: 1.0\r\n";
if (info.ccEmail.size() > 0)
{
std::vector<std::string> vecCcList;
for (auto item : info.ccEmail)
{
std::string cc = "=?" + info.charset + "?b?" + base64Encode(item.first.c_str(), item.first.length()) + "?= <" + item.second + ">";
vecCcList.push_back(cc);
}
message << "Cc:" << join(vecCcList, ",") << "\r\n";
}
message << "Content-Type:multipart/mixed; boundary=\"Separator_ztq_000\"\r\n\r\n";
message << "--Separator_ztq_000\r\n";
message << "Content-Type: multipart/alternative; boundary=\"Separator_ztq_111\"\r\n\r\n";
message << "--Separator_ztq_111\r\n";
message << "Content-Type: " << "text/plain" << "; charset=\"" << info.charset << "\"\r\n";
message << "Content-Transfer-Encoding: base64\r\n";
message << "\r\n"; //此处要加，不然邮件正文无内容
message << base64Encode(info.message.c_str(), info.message.length());
message << "\r\n\r\n";
message << "--Separator_ztq_111--\r\n";
//---------------------文件部分处理--------------------------------------
for (auto item : info.attachment)
{
std::string filename = fileBasename(item);
std::string strContext = getFileContents(item.c_str());
if(strContext.empty())
{
std::cerr << "请检查传入的文件路径是否正确,此路径文件添加到附件失败，不发送此文件:" << std::endl;
std::cerr << item << std::endl;
}
else
{
std::string fileContext = base64Encode(strContext.c_str(), strContext.length());
std::string extension = GetFileExtension(filename);
std::string mimetype = GetMimeTypeFromFileName((char*)extension.c_str());
message << "--Separator_ztq_000\r\n";
message << "Content-Type: " << mimetype << "; name=\"" << filename << "\"\r\n";
message << "Content-Transfer-Encoding: base64\r\n";
message << "Content-Disposition: attachment; filename=\"" << filename << "\"\r\n\r\n";
message << fileContext + "\r\n\r\n"; //把读取到的文件内容以二进制形式发送
}
}
//-----------------------------------------------------------
message << "\r\n.\r\n";
return message.str();
}
/***************************************************************************************************/
SslSmtpEmail::~SslSmtpEmail()
{
}
int SslSmtpEmail::Connect()
{
if (SmtpEmail::Connect() == 0)
{
SSL_library_init();
OpenSSL_add_all_algorithms();
SSL_load_error_strings();
m_ctx = SSL_CTX_new(SSLv23_client_method());
m_ssl = SSL_new(m_ctx);
SSL_set_fd(m_ssl, m_socketfd);
SSL_connect(m_ssl);
}
return 0;
}
int SslSmtpEmail::DisConnect()
{
SSL_shutdown(m_ssl);
SSL_free(m_ssl);
SSL_CTX_free(m_ctx);
SmtpEmail::DisConnect();
return 0;
}
int SmtpEmail::SendEmail(const std::string& from, const std::string& passs, const std::string& to, const std::string& subject, const std::string& strMessage)
{
EmailInfo info;
info.charset = "UTF-8";
info.sender = from;
info.password = passs;
info.senderEmail = from;
info.recipientEmail = to;
info.recvList[to] = "";
info.subject = subject;
info.message = strMessage;
return SMTPComunicate(info);
}
int SmtpEmail::SendEmail(const std::string& from, const std::string& passs, const std::vector<std::string>& vecTo,
const std::string& subject, const std::string& strMessage, const std::vector<std::string>& attachment, const std::vector<std::string>& ccList)
{
std::vector<std::string> recvList;
recvList.insert(recvList.end(), vecTo.begin(), vecTo.end());
recvList.insert(recvList.end(), ccList.begin(), ccList.end());
for (auto& item : recvList)
{
EmailInfo info;
info.charset = "UTF-8";
info.sender = from;
info.password = passs;
info.senderEmail = from;;
info.recipientEmail = item;
for (auto item : vecTo)
{
info.recvList[item] = "";
}
info.subject = subject;
info.message = strMessage;
for (auto& item : ccList)
{
info.ccEmail[item] = item;
}
info.attachment = attachment;
if (SMTPComunicate(info) != 0)
{
return -1;
}
}
return 0;
}
int SslSmtpEmail::Read(void * buf, int num)
{
int ret = SSL_read(m_ssl, buf, num);
return ret;
}
int SslSmtpEmail::Write(const void * buf, int num)
{
return SSL_write(m_ssl, buf, num);
}
std::string SimpleSslSmtpEmail::GetEmailBody(const EmailInfo &info)
{
//设定邮件的发送者名称、接收者名称、邮件主题，邮件内容。
std::ostringstream message;
message << "From: =?" << info.charset << "?b?" << base64Encode(info.sender.c_str(), info.sender.length()) << "?= <" << info.senderEmail << ">\r\n";
std::vector<std::string> vecToList;
for (auto item : info.recvList)
{
std::string to = "=?" + info.charset + "?b?" + base64Encode(item.second.c_str(), item.second.length()) + "?= <" + item.first + ">";
vecToList.push_back(to);
}
message << "To: " << join(vecToList, ",") << "\r\n";
message << "Subject: =?" << info.charset << "?b?" << base64Encode(info.subject.c_str(), info.subject.length()) << "?=\r\n";
message << "MIME-Version: 1.0\r\n";
if (info.ccEmail.size() > 0)
{
std::vector<std::string> vecCcList;
for (auto item : info.ccEmail)
{
std::string cc = "=?" + info.charset + "?b?" + base64Encode(item.first.c_str(), item.first.length()) + "?= <" + item.second + ">";
vecCcList.push_back(cc);
}
message << "Cc:" << join(vecCcList, ",") << "\r\n";
}
message << "Content-Type:multipart/mixed; boundary=\"Separator_ztq_000\"\r\n\r\n";
message << "--Separator_ztq_000\r\n";
message << "Content-Type: multipart/alternative; boundary=\"Separator_ztq_111\"\r\n\r\n";
message << "--Separator_ztq_111\r\n";
message << "Content-Type: " << "text/plain" << "; charset=\"" << info.charset << "\"\r\n";
message << "Content-Transfer-Encoding: base64\r\n";
message << "\r\n"; //此处要加，不然邮件正文无内容
message << base64Encode(info.message.c_str(), info.message.length());
message << "\r\n\r\n";
message << "--Separator_ztq_111--\r\n";
//---------------------文件部分处理--------------------------------------
for (auto item : info.attachment)
{
std::string filename = fileBasename(item);
std::string strContext = getFileContents(item.c_str());
if(strContext.empty())
{
std::cerr << "请检查传入的文件路径是否正确,此路径文件添加到附件失败，不发送此文件:" << std::endl;
std::cerr << item << std::endl;
}
else
{
std::string fileContext = base64Encode(strContext.c_str(), strContext.length());
std::string extension = GetFileExtension(filename);
std::string mimetype = GetMimeTypeFromFileName((char*)extension.c_str());
message << "--Separator_ztq_000\r\n";
message << "Content-Type: " << mimetype << "; name=\"" << filename << "\"\r\n";
message << "Content-Transfer-Encoding: base64\r\n";
message << "Content-Disposition: attachment; filename=\"" << filename << "\"\r\n\r\n";
message << fileContext + "\r\n\r\n"; //把读取到的文件内容以二进制形式发送
}
}
//-----------------------------------------------------------
message << "\r\n.\r\n";
return message.str();
}
测试代码 main.cpp
SendEmail函数重载，支持基本的简单发送文本邮件，和支持附件、抄送、以及发给多人的发送方式，亲测能够发送成功，默认发送的编码是utf-8格式
#include <iostream>
#include <stdio.h>
#include "mail.h"
int main()
{
std::string from = "xxxx@163.com";
std::string passs ="xxxxx";//这里替换成自己的授权码
std::string to = "xxx@126.com";
std::string subject = "hello";
std::string strMessage = "test";
std::vector<std::string> vecTo; //发送列表
vecTo.push_back("xxx@126.com");
std::vector<std::string> ccList;
// ccList.push_back("xxx@xxx.com.cn");//抄送列表
std::vector<std::string> attachment;
attachment.push_back("mail.h");
attachment.push_back("/home/soft/Desktop/openwrt-sdk-imx6ul/1/mybuild.sh");
SmtpBase *base;
SimpleSmtpEmail m_mail("smtp.163.com","25");
base = &m_mail;
//base->SendEmail(from, passs, to, subject, strMessage);//普通的文本发送，明文发送
SimpleSslSmtpEmail m_ssl_mail("smtp.163.com","465");
base=&m_ssl_mail;
//base->SendEmail(from, passs, to, subject, strMessage);
base->SendEmail(from, passs,vecTo,subject,strMessage,attachment,ccList);//加密的发送，支持抄送、附件等
return 0;
}
邮箱收件箱
查看邮件头
收到的邮件
参考链接：
C++基于Smtp协议发送邮件
SMTP基本原理与C++实现向多人发送邮件
后记
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