Sendmail和Postfix哪种好?怎么利用此来建立Linux Mail Server反垃圾策略?

Posted 2023-04-18

我建议：Postfix，它的处理邮件的速度要快，能力强。如何建立Linux Mail Server反垃圾策略，这个就比较多了，先了解postfix后再找这个反垃圾策略，不会很难！ 参考技术A postfix

MTA---smtp(25,postfix,sendmail),Pop3(110,Devocot), MUA(foxmail) IMAP(server,client rsync)

 

利用telnet进行SMTP的验证

=========先计算BASE64编码的用户名密码，认证登录需要用到===========
[[email protected] crazywill]$ perl -MMIME::Base64 -e ‘print encode_base64("crazywill");‘
Y3Jhenl3aWxs

[[email protected] crazywill]$ perl -MMIME::Base64 -e ‘print encode_base64("mypassword");‘
bXlwYXNzd29yZA==

======================开始SMTP发信操作==========================
[[email protected] crazywill]$ telnet smtp.163.com 25 #telnet登录25端口
Trying 202.108.5.81...
Connected to smtp.163.com.
Escape character is ‘^]‘.
220 163.com Coremail SMTP(Anti Spam) System
EHLO smtp.163.com # 握手 :)
250-mail
250-PIPELINING
250-AUTH LOGIN PLAIN
250-AUTH=LOGIN PLAIN
250 8BITMIME
AUTH LOGIN # 开始认证登录
334 dXNlcm5hbWU6
crazywill
334 UGFzc3dvcmQ6
mypassword
535 Error: authentication failed # 直接用户名密码不能登录
AUTH LOGIN
334 dXNlcm5hbWU6
Y3Jhenl3aWxs
334 UGFzc3dvcmQ6
bXlwYXNzd29yZA==
235 Authentication successful # 使用Base64编码则成功登录
MAIL FROM:<[email protected]> # 邮件发送方
553 You are not authorized to send mail, authentication is required # 不可伪造发送邮件
MAIL FROM:<[email protected]> # 邮件发送方
250 Mail OK
RCPT TO:<[email protected]> # 邮件的接收方，若有多个收件人，则重复这一语句多次。
250 Mail OK
DATA # 邮件体内容
354 Please start mail input.
TO: [email protected] # 此处的TO，FROM，等内容，可以随便造假 :) 可以骗人但骗不了懂得查看邮件源码的。
FROM: [email protected]
SUBJECT: test by telnet/smtp

test, just a test. # 邮件正文内容，与Header部分空一行开始写
. # 邮件写完，以一个句点加回车结果。
250 Mail OK queued as smtp10,wKjADQ2ApxRnnqBE0CWaEw==.38326S3 # 返回250 表示发送成功。
NOOP # 空语句，不执行任何操作，一般用来保持和服务器连接，不要掉线
250 OK
QUIT # 退出
221 Closing connection. Good bye.
Connection closed by foreign host.
[[email protected] crazywill]$


======================开始POP3收信操作==========================

[[email protected] crazywill]$ telnet pop.163.com 110 #telnet登录110端口
Trying 202.108.5.104...
Connected to pop.163.com.
Escape character is ‘^]‘.
+OK Welcome to coremail Mail Pop3 Server (163com[20050206])
USER crazywill # 用户名
+OK core mail
PASS mypassword # 登录密码
+OK 254 message(s) [27676669 byte(s)]
STAT # 查看邮箱状态
+OK 254 27676669
LIST # 邮件列表
+OK 254 27676669
1 2468
2 21945
3 33136
4 2071
5 3364
6 18906
7 3136
8 24764
.................

TOP 254 0 # 查看指定邮件的邮件头，0表示查看整个邮件头，其它正整数表示限制返回多少行。
+OK core mail
Received: from smtp.63.com (unknown [58.252.70.158])
by smtp5 (Coremail) with SMTP id wKjREDrA9gIfFqlEjCnRAg==.29062S4;
Mon, 03 Jul 2006 21:07:18 +0800 (CST)
TO: [email protected]
FROM : [email protected] # 这里即前面发信时伪造的一个假发送人信息，平时正常操作只显示这个。
SUBJECT: test by telnet/smtp # 邮件主题
Message-Id: <44A91687.0E6F6C.07562>
Date: Mon, 3 Jul 2006 21:07:19 +0800 (CST)
Sender: [email protected] # 这里是真正的发送人，不可伪造。


.
RETR 254 # 获取指定邮件
+OK 354 octets
Received: from smtp.63.com (unknown [58.252.70.158])
by smtp5 (Coremail) with SMTP id wKjREDrA9gIfFqlEjCnRAg==.29062S4;
Mon, 03 Jul 2006 21:07:18 +0800 (CST)
TO: [email protected]
FROM : [email protected]
SUBJECT: test by telnet/smtp
Message-Id: <44A91687.0E6F6C.07562>
Date: Mon, 3 Jul 2006 21:07:19 +0800 (CST)
Sender: [email protected]

test, just a test.
.

DELE 254 # 删除第254封邮件
+OK core mail
STAT # 查看邮箱状态
+OK 253 27676315
QUIT # 退出
+OK core mail
Connection closed by foreign host.
[[email protected] crazywill]$


===============================================================

QUESTION:
如何发送给多人，如何CC，BCC？

ANSWER: (此答案由SnifferPro监听OUTLOOK发送多人邮件分析出来的)
同一封信发送/抄送给多人，在MAIL FROM:<...> 后，多次使用 RCPT TO:<...>
每次一个邮件地址，需要发给多少人就 RCPT TO 多少次。

在DATA里面写的CC，BCC，TO，等信息只起显示作用，与实际发送人接收人无关。

CC与BCC的差别：同样都是RCPT TO指定收件人，但是邮件客户端程序，不会将BCC的收件人写到DATA要传送的数据里。

 

使用IMAP

[[email protected] crazywill]$ telnet 192.168.0.1 143      #telnet登录IMAP协议的143端口
Trying 192.168.0.1...
Connected to xxxxxx
Escape character is ‘^]‘.
* OK xxxxxxx System IMap Server Ready
A01 LOGIN abc 123       #用户登录
A01 OK LOGIN completed
A02 LIST "" *           #列出所有信箱列表
* LIST () "/" "INBOX"
* LIST () "/" "Drafts"
* LIST () "/" "Sent Items"
* LIST () "/" "Trash"
* LIST () "/" "Junk E-mail"
* LIST () "/" "Virus Items"
* LIST () "/" "&XfJT0ZABkK5O9g-"
* LIST () "/" "&g0l6Pw-"
* LIST () "/" "&XfJT0ZABkK5O9g-/DailyReport"
* LIST () "/" "Jira"
* LIST () "/" "Admin"
* LIST () "/" "&V4NXPpCuTvY-"
A02 OK LIST Completed
A03 Select INBOX         #选择收件箱
* 37 EXISTS
* 0 RECENT
* OK [UIDVALIDITY 1] UIDs valid
* FLAGS (\\Answered \\Seen \\Deleted \\Draft)
* OK [PERMANENTFLAGS (\\Answered \\Seen \\Deleted \\Draft)] Limited
A03 OK [READ-WRITE] SELECT completed
A04 Search ALL           #查询收件箱所有邮件
* OK X-SEARCH in progress
* OK X-SEARCH in progress
* OK X-SEARCH in progress
* SEARCH 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37
A04 OK SEARCH completed            # 列出符合条件的邮件序号(ALL表示列出当前信箱INBOX中的所有邮件)
A05 Search new           #查询收件箱所有新邮件
* OK X-SEARCH in progress
* OK X-SEARCH in progress
* OK X-SEARCH in progress
* SEARCH
A05 OK SEARCH completed            #找不到任何新邮件
A06 Fetch 5 full         #获取第5封邮件的邮件头
* 5 FETCH (INTERNALDATE "27-Jun-2006 14:00:27 +0800" FLAGS (\\Seen) ENVELOPE ("Tue, 27 Jun 2006 13:56:51 +0800" "test " (("xxxxxx" NIL "xxxx" "xxxxxx")) (("xxxxxx" NIL "xxxx" "xxxxxx")) (("xxxxxx" NIL "xxxx" "xxxxxx")) ((NIL NIL "xxx" "xxxxx")) NIL NIL NIL "<[email protected]>") BODY (("text" "plain" ("charset" "gb2312") NIL NIL "base64" 14 2) ("text" "html" ("charset" "gb2312") NIL NIL "base64" 420 7) "alternative") RFC822.SIZE 1396)
A06 OK Fetch completed
A07 Fetch 5 rfc822       #获取第5封邮件的完整内容
* 5 FETCH (RFC822 {1396}
[这里是邮件内容，太长，略...]
A07 OK Fetch completed
A08 Fetch 5 flags        #查询第5封邮件的标志位
A08 OK Fetch completed
A09 Store 5 +flags.silent (\\deleted)          #设置标志位为删除
A09 OK STORE completed
A10 Expunge              #永久删除当前邮箱INBOX中所有设置了\\deleted标志的信件
A10 OK EXPUNGE completed
A11 noop                  # 空语句
A11 OK NOOP completed


A20 LOGOUT               #退出
* BYE IMAP4rev1 Server logging out
A20 OK LOGOUT completed
Connection closed by foreign host.
[[email protected] crazywill]$