Abstract: On the basis of the analysis of SMTP protocol and SMTP proxy server principle, a SMTP transparent proxy for security detection is developed under Linux environment. Some key techniques are designed and implemented, such as redirecting port, concurrent mail service, getting the address and port of the server, handling annex. System test shows that the SMTP proxy is transparent to users, and can deputize for multiple e-mail services, prevent virus intrusion and leakage of internal content efficiently.

Key words: Linux, SMTP, proxy server, transparent proxy, security detection

摘要： 通过对SMTP协议和SMTP代理服务器原理的分析，在Linux环境下开发了面向安全检测的SMTP透明代理，设计并实现了一些关键技术，包括端口重定向、并发邮件服务、获取邮件服务器的地址和端口号、处理附件等。测试表明，该系统实现了用户透明功能，可以代理多种邮件服务，有效地防止了病毒入侵和内容泄露。

关键词: Linux, SMTP, 代理服务器, 透明代理, 安全检测

CLC Number: 

• TP309