用openssl跟Gmail的smtp对话（一）

旧城等待， 2022-08-05 12:19 296阅读 0赞

一、目的

Gmail的webmail虽然常常报系统遇到错误，用起来不太爽，但是smtp/pop3还是蛮厚道的。

服务稳定，被GFW拦截的概率也小一些，可能是采用SSL加密通讯的缘故吧。所以研究一下gmail的smtp连接还是很有意义的。我们先用手头上的工具进行实际操作，对ssl的连接有个感性的认识，然后用C写一个测试程序，最终的目标是用C++写一个COM可以供ASP调用，当然所谓的C++当然是指基于M$的ATL了，纯C++的COM是学院派的人干的活，作为工程人员应用才是首要目的。为什么要写成COM的，因为纵观网络编程的世界就asp没有实现（或者实现了没有开源）gmail的发信功能，不管jmail还是codsys都没有，可是是没有必要，或者是我孤陋寡闻，其他的php、asp.net、java都很容易实现此功能。在asp遍地的过度，写出来估计还是有一定价值的。

二、要求

1.  SSL的大致内容，搞清楚C/S间如何握手的就行了
2.  OpenSSL，开源的成功案例，没有OpenSSL估计我们只能望机兴叹了，搞明白SSL的算法好像不是一两个月能明白的，所有掌握Openssl是必须的，不用太深入，但是起码能知道如何建立ssl的上下文和封装socket的发送和接收。
3.  C/C++基础，上过理工科的人都应该知道。俺打算用C来写HelloGmail程序，被逼无奈啊，谁让OpenSSL是用C写的呢！
4.  COM基础，至少要知道COM是如何实现二进制级代码共享的，如何用ATL做COM的。俺得毕业论文是搞fortran和java的混合编程，所以对混合编程情有独钟。当时还不知道有COM这回事，走了很多的弯路：java调c++写的dll，c++的dll调fotran的dll，相当的丑陋 ^^

三、开始

1.简单的认识

我们先在cmd窗口连连gmail看看，把过程弄明白先。由于采用了ssl，所以用普通的telnet是无法直接连接到gmail的smtp的，我们需要openssl构建一个ssl层，由openssl来负责繁琐的ssl协议

我们先要编译OpenSSL，下面这篇博文已经写得很好，俺就不啰嗦了

[http://blog.tom.com/blog/read.php?bloggerid=329665&blogid=41867][http_blog.tom.com_blog_read.php_bloggerid_329665_blogid_41867]

我在E:/openssl-0.9.8e下

<table style="width: 95%; border-collapse: collapse;"> 
 <tbody> 
 <tr> 
 <td> <code>E:/openssl-0.9.8e/out32dll&gt;openssl s_client -connect smtp.gmail.com:465 Loading 'screen' into random state - done CONNECTED(00000790) depth=0 /C=US/ST=California/L=Mountain View/O=Google Inc/CN=smtp.gmail.com verify error:num=20:unable to get local issuer certificate verify return:1 depth=0 /C=US/ST=California/L=Mountain View/O=Google Inc/CN=smtp.gmail.com verify error:num=27:certificate not trusted verify return:1 depth=0 /C=US/ST=California/L=Mountain View/O=Google Inc/CN=smtp.gmail.com verify error:num=21:unable to verify the first certificate verify return:1 --- Certificate chain &nbsp;0 s:/C=US/ST=California/L=Mountain View/O=Google Inc/CN=smtp.gmail.com &nbsp;&nbsp;&nbsp;i:/C=ZA/ST=Western Cape/L=Cape Town/O=Thawte Consulting cc/OU=Certification S ervices Division/CN=Thawte Premium Server CA/emailAddress=premium-server@thawte. com --- Server certificate -----BEGIN CERTIFICATE----- MIIDYzCCAsygAwIBAgIQYZrZzKZNh1fKVFuUlZ6rKzANBgkqhkiG9w0BAQUFADCB zjELMAkGA1UEBhMCWkExFTATBgNVBAgTDFdlc3Rlcm4gQ2FwZTESMBAGA1UEBxMJ Q2FwZSBUb3duMR0wGwYDVQQKExRUaGF3dGUgQ29uc3VsdGluZyBjYzEoMCYGA1UE CxMfQ2VydGlmaWNhdGlvbiBTZXJ2aWNlcyBEaXZpc2lvbjEhMB8GA1UEAxMYVGhh d3RlIFByZW1pdW0gU2VydmVyIENBMSgwJgYJKoZIhvcNAQkBFhlwcmVtaXVtLXNl cnZlckB0aGF3dGUuY29tMB4XDTA3MDczMDE2NTgwN1oXDTA4MDcyOTE2NTgwN1ow aDELMAkGA1UEBhMCVVMxEzARBgNVBAgTCkNhbGlmb3JuaWExFjAUBgNVBAcTDU1v dW50YWluIFZpZXcxEzARBgNVBAoTCkdvb2dsZSBJbmMxFzAVBgNVBAMTDnNtdHAu Z21haWwuY29tMIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDQF2mUMNM+qw/i wMVSP2D0pgKb0M3RyWHBTQkno3W4y5TeH8LALnqv9/+Th4wZ5PrZ7YPQjmCxdtz6 Lm5Yx19nDXNw97or6SXvAoZSF+bwh76UFqxpImAGJzvj8Ro7rNkMidJa+KgGaIng sIcWuqsj0rrK1AXoUHKmO4N5t0c6XwIDAQABo4GmMIGjMB0GA1UdJQQWMBQGCCsG AQUFBwMBBggrBgEFBQcDAjBABgNVHR8EOTA3MDWgM6Axhi9odHRwOi8vY3JsLnRo YXd0ZS5jb20vVGhhd3RlUHJlbWl1bVNlcnZlckNBLmNybDAyBggrBgEFBQcBAQQm MCQwIgYIKwYBBQUHMAGGFmh0dHA6Ly9vY3NwLnRoYXd0ZS5jb20wDAYDVR0TAQH/ BAIwADANBgkqhkiG9w0BAQUFAAOBgQCUoTmFzdJX+2Pz9FhI+H88lFIeBcFnxpPO CHO7zs/J3ZI6ZmkuQm4az89tRqvKvRFrQm2CRlzntqWjSdcsIYlKKGZ32iclpNKw 1aW/Q3IIyyZTTUo9DJezyCrFBV7JxFXOQgYd45+YxPVUNnkw1lTd4RqweuB5p7r4 nObS2EE7cA== -----END CERTIFICATE----- subject=/C=US/ST=California/L=Mountain View/O=Google Inc/CN=smtp.gmail.com issuer=/C=ZA/ST=Western Cape/L=Cape Town/O=Thawte Consulting cc/OU=Certification &nbsp;Services Division/CN=Thawte Premium Server CA/emailAddress=premium-server@thawt e.com --- No client certificate CA names sent --- SSL handshake has read 1025 bytes and written 314 bytes --- New, TLSv1/SSLv3, Cipher is DES-CBC3-SHA Server public key is 1024 bit Compression: NONE Expansion: NONE SSL-Session: &nbsp;&nbsp;&nbsp;&nbsp;Protocol : TLSv1 &nbsp;&nbsp;&nbsp;&nbsp;Cipher : DES-CBC3-SHA &nbsp;&nbsp;&nbsp;&nbsp;Session-ID: AA41A4829FAB5945984CCE49EF1A135703C437F1F169F1BB9D2E8417D6B50B38 &nbsp;&nbsp;&nbsp;&nbsp;Session-ID-ctx: &nbsp;&nbsp;&nbsp;&nbsp;Master-Key: BEE0D063AF73B0645845F359D8E8A488EC33A38497D381C46ECE6F0E7C8DBFB0 2EA5A1EE3FFD583DD111EC9567EE6D8F &nbsp;&nbsp;&nbsp;&nbsp;Key-Arg : None &nbsp;&nbsp;&nbsp;&nbsp;Start Time: 1188884689 &nbsp;&nbsp;&nbsp;&nbsp;Timeout : 300 (sec) &nbsp;&nbsp;&nbsp;&nbsp;Verify return code: 21 (unable to verify the first certificate) --- 220 mx.google.com ESMTP c5sm1770312qbc EHLO localhost 250-mx.google.com at your service, [218.80.208.72] 250-SIZE 28311552 250-8BITMIME 250-AUTH LOGIN PLAIN 250 ENHANCEDSTATUSCODES AUTH LOGIN 334 VXNlcm5hbWU6 eHVxaW55b25nQGdtYWlsLmNvbQ== 334 UGFzc3dvcmQ6 xxxxxxxxx 235 2.7.0 Accepted</code> </td> 
 </tr> 
 </tbody> 
</table>

上面的连接其实是有问题，因为我们没有装载我们的证书，所以到RCPT命令的时候，gmail就把我们给踢了，我们在C写的HelloGmail中将会装载我们的自己的证书。

2.用C写发信程序

<table style="width: 95%; border-collapse: collapse;"> 
 <tbody> 
 <tr> 
 <td> <code>#include "stdafx.h" /****************************************************************************************** *SSL/TLS客户端程序WIN32版(以demos/cli.cpp为基础) *需要用到动态连接库libeay32.dll,ssleay.dll, *同时在setting中加入ws2_32.lib libeay32.lib ssleay32.lib, *以上库文件在编译openssl后可在out32dll目录下找到, *所需证书文件请参照文章自行生成*/ ******************************************************************************************/ #include &lt;stdio.h&gt; #include &lt;stdlib.h&gt; #include &lt;memory.h&gt; #include &lt;errno.h&gt; #include &lt;sys/types.h&gt; #include &lt;winsock2.h&gt; #include "openssl/rsa.h" #include "openssl/crypto.h" #include "openssl/x509.h" #include "openssl/pem.h" #include "openssl/ssl.h" #include "openssl/err.h" #include "openssl/rand.h" #include &lt;openssl/sha.h&gt; #include &lt;openssl/hmac.h&gt; #include &lt;openssl/evp.h&gt; #include &lt;openssl/bio.h&gt; #include &lt;openssl/buffer.h&gt; /*所有需要的参数信息都在此处以#define的形式提供*/ #define CERTF "client.pem" /*客户端的证书(需经CA签名)*/ #define KEYF "client.key" /*客户端的私钥(建议加密存储)*/ #define CACERT "ca.pem" /*CA 的证书*/ #define PORT 465 /*服务端的端口*/ #define SERVER_ADDR "209.85.147.111" /*服务段的IP地址*/ #define GMAILUSERNAME "xuqinyong@gmail.com"/*Gmail 帐号*/ #define GMAILPASSWORD "xxxx"/*Gmail 帐号密码*/ #define CHK_NULL(x) if ((x)==NULL) exit (-1) #define CHK_ERR(err,s) if ((err)==-1) { perror(s); exit(-2); } #define CHK_SSL(err) if ((err)==-1) { ERR_print_errors_fp(stderr); exit(-3); } /*仍数据*/ int put_line(SSL* ssl,char* cmd) { &nbsp;&nbsp;&nbsp;&nbsp;int err; &nbsp;&nbsp;&nbsp;&nbsp;printf("C: %s",cmd); &nbsp;&nbsp;&nbsp;&nbsp;err = SSL_write (ssl, cmd, strlen(cmd)); &nbsp;&nbsp;&nbsp;&nbsp;CHK_SSL(err); &nbsp;&nbsp;&nbsp;&nbsp;return 1; } /*读数据*/ int get_line(SSL* ssl) { &nbsp;&nbsp;&nbsp;&nbsp;char buf [4096]; &nbsp;&nbsp;&nbsp;&nbsp;int err; &nbsp;&nbsp;&nbsp;&nbsp;err = SSL_read (ssl, buf, sizeof(buf) - 1); &nbsp;&nbsp;&nbsp;&nbsp;CHK_SSL(err); &nbsp;&nbsp;&nbsp;&nbsp;buf[err] = '/0'; &nbsp;&nbsp;&nbsp;&nbsp;printf ("S: :%s", buf); &nbsp;&nbsp;&nbsp;&nbsp;free(buf); &nbsp;&nbsp;&nbsp;&nbsp;return 1; } char *base64_encode(char *input) { &nbsp;&nbsp;&nbsp;&nbsp;BIO *bmem, *b64; &nbsp;&nbsp;&nbsp;&nbsp;BUF_MEM *bptr; &nbsp;&nbsp;&nbsp;&nbsp;b64 = BIO_new(BIO_f_base64()); &nbsp;&nbsp;&nbsp;&nbsp;bmem = BIO_new(BIO_s_mem()); &nbsp;&nbsp;&nbsp;&nbsp;b64 = BIO_push(b64, bmem); &nbsp;&nbsp;&nbsp;&nbsp;BIO_write(b64, input, strlen(input)); &nbsp;&nbsp;&nbsp;&nbsp;BIO_flush(b64); &nbsp;&nbsp;&nbsp;&nbsp;BIO_get_mem_ptr(b64, &amp;bptr); &nbsp;&nbsp;&nbsp;&nbsp;char *buff = (char *)malloc(bptr-&gt;length); &nbsp;&nbsp;&nbsp;&nbsp;memcpy(buff, bptr-&gt;data, bptr-&gt;length-1); &nbsp;&nbsp;&nbsp;&nbsp;buff[bptr-&gt;length-1] = 0; &nbsp;&nbsp;&nbsp;&nbsp;BIO_free_all(b64); &nbsp;&nbsp;&nbsp;&nbsp;return buff; } /*捏造信头*/ char* makeHeader() { &nbsp;&nbsp;&nbsp;&nbsp;char buf[128]; &nbsp;&nbsp;&nbsp;&nbsp;char tmp[1024]; &nbsp;&nbsp;&nbsp;&nbsp;char *rnt,*next; &nbsp;&nbsp;&nbsp;&nbsp;int n,length; &nbsp;&nbsp;&nbsp;&nbsp;n = length = 0; &nbsp;&nbsp;&nbsp;&nbsp;next = tmp; &nbsp;&nbsp;&nbsp;&nbsp;n = sprintf(buf,"Date: %s/r/n","date"); &nbsp;&nbsp;&nbsp;&nbsp;memcpy(tmp,buf,n); &nbsp;&nbsp;&nbsp;&nbsp;next+= n; &nbsp;&nbsp;&nbsp;&nbsp;length += n; &nbsp;&nbsp;&nbsp;&nbsp;n = sprintf(buf,"Return-Path: %s/r/n",GMAILUSERNAME); &nbsp;&nbsp;&nbsp;&nbsp;memcpy(next,buf,n); &nbsp;&nbsp;&nbsp;&nbsp;next+= n; &nbsp;&nbsp;&nbsp;&nbsp;length += n; &nbsp;&nbsp;&nbsp;&nbsp;n = sprintf(buf,"To: %s/r/n",GMAILUSERNAME); &nbsp;&nbsp;&nbsp;&nbsp;memcpy(next,buf,n); &nbsp;&nbsp;&nbsp;&nbsp;next+= n; &nbsp;&nbsp;&nbsp;&nbsp;length += n; &nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;n = sprintf(buf, "From: =?UTF-8?B?%s?= &lt;%s&gt;/r/n",base64_encode(GMAILUSERNAME),GMAILUSERNAME); &nbsp;&nbsp;&nbsp;&nbsp;memcpy(next,buf,n); &nbsp;&nbsp;&nbsp;&nbsp;next+= n; &nbsp;&nbsp;&nbsp;&nbsp;length += n; &nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;n = sprintf(buf, "Subject: =?UTF-8?B?%s?=/r/n",base64_encode("Test mail via C")); &nbsp;&nbsp;&nbsp;&nbsp;memcpy(next,buf,n); &nbsp;&nbsp;&nbsp;&nbsp;next+= n; &nbsp;&nbsp;&nbsp;&nbsp;length += n; &nbsp;&nbsp;&nbsp;&nbsp;n = sprintf(buf, "MIME-Version: 1.0/r/n"); &nbsp;&nbsp;&nbsp;&nbsp;memcpy(next,buf,n); &nbsp;&nbsp;&nbsp;&nbsp;next+= n; &nbsp;&nbsp;&nbsp;&nbsp;length += n; &nbsp;&nbsp;&nbsp;&nbsp;n = sprintf(buf, "Content-Transfer-Encoding: base64/r/n"); &nbsp;&nbsp;&nbsp;&nbsp;memcpy(next,buf,n); &nbsp;&nbsp;&nbsp;&nbsp;next+= n; &nbsp;&nbsp;&nbsp;&nbsp;length += n; &nbsp;&nbsp;&nbsp;&nbsp;n = sprintf(buf, "Content-Type: text/html; charset=/"UTF-8/"/r/n/r/n"); &nbsp;&nbsp;&nbsp;&nbsp;memcpy(next,buf,n); &nbsp;&nbsp;&nbsp;&nbsp;next+= n; &nbsp;&nbsp;&nbsp;&nbsp;length += n; &nbsp;&nbsp;&nbsp;&nbsp;tmp[length] = 0; &nbsp;&nbsp;&nbsp;&nbsp;rnt = (char *)malloc(length); &nbsp;&nbsp;&nbsp;&nbsp;strcpy(rnt, tmp); &nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;return rnt; } char* makeBody(char* instr) { &nbsp;&nbsp;&nbsp;&nbsp;char* tmp; &nbsp;&nbsp;&nbsp;&nbsp;char* rnt; &nbsp;&nbsp;&nbsp;&nbsp;tmp = base64_encode(instr); &nbsp;&nbsp;&nbsp;&nbsp;rnt = (char *)malloc(strlen(tmp)); &nbsp;&nbsp;&nbsp;&nbsp;strcpy(rnt, tmp); &nbsp;&nbsp;&nbsp;&nbsp;rnt = strcat(rnt,"/r/n"); &nbsp;&nbsp;&nbsp;&nbsp;return rnt; } int main () { &nbsp;&nbsp;&nbsp;&nbsp;int err; &nbsp;&nbsp;&nbsp;&nbsp;int sd; &nbsp;&nbsp;&nbsp;&nbsp;struct sockaddr_in sa; &nbsp;&nbsp;&nbsp;&nbsp;SSL_CTX* ctx; &nbsp;&nbsp;&nbsp;&nbsp;SSL* ssl; &nbsp;&nbsp;&nbsp;&nbsp;X509* server_cert; &nbsp;&nbsp;&nbsp;&nbsp;char* str; &nbsp;&nbsp;&nbsp;&nbsp;SSL_METHOD *meth; &nbsp;&nbsp;&nbsp;&nbsp;int seed_int[100]; /*存放随机序列*/ &nbsp;&nbsp;&nbsp;&nbsp;WSADATA wsaData; &nbsp;&nbsp;&nbsp;&nbsp;if(WSAStartup(MAKEWORD(2,2),&amp;wsaData) != 0){ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;printf("WSAStartup()fail:%d/n",GetLastError()); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;return -1; &nbsp;&nbsp;&nbsp;&nbsp;} &nbsp;&nbsp;&nbsp;&nbsp;//OpenSSL_add_ssl_algorithms(); /*初始化*/ &nbsp;&nbsp;&nbsp;&nbsp;SSL_library_init(); &nbsp;&nbsp;&nbsp;&nbsp;SSL_load_error_strings(); /*为打印调试信息作准备*/ &nbsp;&nbsp;&nbsp;&nbsp;meth=SSLv23_method(); &nbsp;&nbsp;&nbsp;&nbsp;ctx = SSL_CTX_new (meth); &nbsp;&nbsp;&nbsp;&nbsp;CHK_NULL(ctx); &nbsp;&nbsp;&nbsp;&nbsp;SSL_CTX_set_default_passwd_cb_userdata(ctx, "password"); &nbsp;&nbsp;&nbsp;&nbsp;if(!(SSL_CTX_use_certificate_chain_file(ctx, CERTF))){ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ERR_print_errors_fp(stderr); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;exit(-2); &nbsp;&nbsp;&nbsp;&nbsp;} &nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;if(!(SSL_CTX_use_PrivateKey_file(ctx, CERTF,SSL_FILETYPE_PEM))){ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ERR_print_errors_fp(stderr); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;exit(-3); &nbsp;&nbsp;&nbsp;&nbsp;} &nbsp;&nbsp;&nbsp;&nbsp;/* Load the CAs we trust*/ &nbsp;&nbsp;&nbsp;&nbsp;if(!(SSL_CTX_load_verify_locations(ctx, CACERT,0))){ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;printf("Load CA failed!/n"); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;exit(-4); &nbsp;&nbsp;&nbsp;&nbsp;} &nbsp;&nbsp;&nbsp;&nbsp;/*构建随机数生成机制,WIN32平台必需*/ &nbsp;&nbsp;&nbsp;&nbsp;srand( (unsigned)time( NULL ) ); &nbsp;&nbsp;&nbsp;&nbsp;for( int i = 0; i &lt; 100;i++ ) &nbsp;&nbsp;&nbsp;&nbsp;seed_int[i] = rand(); &nbsp;&nbsp;&nbsp;&nbsp;RAND_seed(seed_int, sizeof(seed_int)); &nbsp;&nbsp;&nbsp;&nbsp;/*以下是正常的TCP socket建立过程 .............................. */ &nbsp;&nbsp;&nbsp;&nbsp;printf("Begin tcp socket.../n"); &nbsp;&nbsp;&nbsp;&nbsp;sd = socket (AF_INET, SOCK_STREAM, 0); CHK_ERR(sd, "socket"); &nbsp;&nbsp;&nbsp;&nbsp;memset (&amp;sa, '/0', sizeof(sa)); &nbsp;&nbsp;&nbsp;&nbsp;sa.sin_family = AF_INET; &nbsp;&nbsp;&nbsp;&nbsp;sa.sin_addr.s_addr = inet_addr (SERVER_ADDR); /* Server IP */ &nbsp;&nbsp;&nbsp;&nbsp;sa.sin_port = htons (PORT); /* Server Port number */ &nbsp;&nbsp;&nbsp;&nbsp;err = connect(sd, (struct sockaddr*) &amp;sa, &nbsp;&nbsp;&nbsp;&nbsp;sizeof(sa)); &nbsp;&nbsp;&nbsp;&nbsp;CHK_ERR(err, "connect"); &nbsp;&nbsp;&nbsp;&nbsp;/* TCP 链接已建立.开始 SSL 握手过程.......................... */ &nbsp;&nbsp;&nbsp;&nbsp;printf("Begin SSL negotiation /n"); &nbsp;&nbsp;&nbsp;&nbsp;ssl = SSL_new (ctx); &nbsp;&nbsp;&nbsp;&nbsp;CHK_NULL(ssl); &nbsp;&nbsp;&nbsp;&nbsp;SSL_set_fd (ssl, sd); &nbsp;&nbsp;&nbsp;&nbsp;err = SSL_connect (ssl); &nbsp;&nbsp;&nbsp;&nbsp;CHK_SSL(err); &nbsp;&nbsp;&nbsp;&nbsp;/*打印所有加密算法的信息(可选)*/ &nbsp;&nbsp;&nbsp;&nbsp;printf ("SSL connection using %s/n", SSL_get_cipher (ssl)); &nbsp;&nbsp;&nbsp;&nbsp;/*得到服务端的证书并打印些信息(可选) */ &nbsp;&nbsp;&nbsp;&nbsp;server_cert = SSL_get_peer_certificate (ssl); &nbsp;&nbsp;&nbsp;&nbsp;CHK_NULL(server_cert); &nbsp;&nbsp;&nbsp;&nbsp;printf ("Server certificate:/n"); &nbsp;&nbsp;&nbsp;&nbsp;str = X509_NAME_oneline (X509_get_subject_name (server_cert),0,0); &nbsp;&nbsp;&nbsp;&nbsp;CHK_NULL(str); &nbsp;&nbsp;&nbsp;&nbsp;printf ("/t subject: %s/n", str); &nbsp;&nbsp;&nbsp;&nbsp;free (str); &nbsp;&nbsp;&nbsp;&nbsp;str = X509_NAME_oneline (X509_get_issuer_name (server_cert),0,0); &nbsp;&nbsp;&nbsp;&nbsp;CHK_NULL(str); &nbsp;&nbsp;&nbsp;&nbsp;printf ("/t issuer: %s/n", str); &nbsp;&nbsp;&nbsp;&nbsp;free (str); &nbsp;&nbsp;&nbsp;&nbsp;X509_free (server_cert); /*如不再需要,需将证书释放 */ &nbsp;&nbsp;&nbsp;&nbsp;/* 数据交换开始,用SSL_write,SSL_read代替write,read */ &nbsp;&nbsp;&nbsp;&nbsp;printf("Begin SSL data exchange/n"); &nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;get_line(ssl); &nbsp;&nbsp;&nbsp;&nbsp;put_line(ssl,"EHLO localhost/r/n"); &nbsp;&nbsp;&nbsp;&nbsp;get_line(ssl); &nbsp;&nbsp;&nbsp;&nbsp;put_line(ssl,"AUTH LOGIN/r/n"); &nbsp;&nbsp;&nbsp;&nbsp;get_line(ssl); &nbsp;&nbsp;&nbsp;&nbsp;str = strcat(base64_encode(GMAILUSERNAME),"/r/n"); &nbsp;&nbsp;&nbsp;&nbsp;put_line(ssl,str); &nbsp;&nbsp;&nbsp;&nbsp;free(str); &nbsp;&nbsp;&nbsp;&nbsp;get_line(ssl); &nbsp;&nbsp;&nbsp;&nbsp;str = strcat(base64_encode(GMAILPASSWORD),"/r/n"); &nbsp;&nbsp;&nbsp;&nbsp;put_line(ssl,str); &nbsp;&nbsp;&nbsp;&nbsp;free(str); &nbsp;&nbsp;&nbsp;&nbsp;get_line(ssl); &nbsp;&nbsp;&nbsp;&nbsp;put_line(ssl,"MAIL FROM:&lt;xuqinyong@gmail.com&gt;/r/n"); &nbsp;&nbsp;&nbsp;&nbsp;get_line(ssl); &nbsp;&nbsp;&nbsp;&nbsp;put_line(ssl,"RCPT TO:&lt;xuqinyong@gmail.com&gt;/r/n"); &nbsp;&nbsp;&nbsp;&nbsp;get_line(ssl); &nbsp;&nbsp;&nbsp;&nbsp;put_line(ssl,"DATA/r/n"); &nbsp;&nbsp;&nbsp;&nbsp;get_line(ssl); &nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;str = makeHeader(); &nbsp;&nbsp;&nbsp;&nbsp;put_line(ssl,str); &nbsp;&nbsp;&nbsp;&nbsp;free(str); &nbsp;&nbsp;&nbsp;&nbsp;str = makeBody("body"); &nbsp;&nbsp;&nbsp;&nbsp;put_line(ssl,str); &nbsp;&nbsp;&nbsp;&nbsp;free(str); &nbsp;&nbsp;&nbsp;&nbsp;put_line(ssl,"/r/n./r/n"); &nbsp;&nbsp;&nbsp;&nbsp;get_line(ssl); &nbsp;&nbsp;&nbsp;&nbsp;put_line(ssl,"QUIT/r/n"); &nbsp;&nbsp;&nbsp;&nbsp;get_line(ssl); &nbsp;&nbsp;&nbsp;&nbsp;/* 收尾工作 */ &nbsp;&nbsp;&nbsp;&nbsp;SSL_shutdown (ssl); /* send SSL/TLS close_notify */ &nbsp;&nbsp;&nbsp;&nbsp;shutdown (sd,2); &nbsp;&nbsp;&nbsp;&nbsp;SSL_free (ssl); &nbsp;&nbsp;&nbsp;&nbsp;SSL_CTX_free (ctx); &nbsp;&nbsp;&nbsp;&nbsp;return 0; } </code> </td> 
 </tr> 
 </tbody> 
</table>

参考资料

[Beginner's Tutorial: COM/ATL Simple Project][Beginner_s Tutorial_ COM_ATL Simple Project]

[http_blog.tom.com_blog_read.php_bloggerid_329665_blogid_41867]: http://blog.tom.com/blog/read.php?bloggerid=329665&blogid=41867
[Beginner_s Tutorial_ COM_ATL Simple Project]: http://www.codeproject.com/atl/com_atl.asp