增加防止发件人身份伪造的配置：

 代码如下  

# smtpd related config
smtpd_recipient_restrictions =
  permit_mynetworks,
  permit_sasl_authenticated,
#  reject_non_fqdn_hostname,
  reject_non_fqdn_sender,
  reject_non_fqdn_recipient,
  reject_unauth_destination,
  reject_unauth_pipelining,
  reject_invalid_hostname

 

smtpd_sender_restrictions =
  permit_mynetworks,
  check_recipient_access hash:/etc/postfix/local_recipient,
  permit_sasl_authenticated,
  reject_sender_login_mismatch,
  reject_authenticated_sender_login_mismatch,
  reject_unauthenticated_sender_login_mismatch,
  reject_unknown_sender_domain

# SMTP AUTH config here
broken_sasl_auth_clients = yes
smtpd_sasl_auth_enable = yes
smtpd_sasl_security_options = noanonymous

　　补充：

　　配置extmail不允许伪造不存在的本地邮件地址发邮件,不允许并仿冒他人邮件地址发送邮件

　　cd /etc/postfix/

　　cat >mysql_virtual_sender_maps.cf<

　　user = extmail

　　password = extmail

　　hosts = localhost

　　dbname = extmail

　　table = mailbox

　　select_field = username

　　where_field = username

　　additional_conditions = AND active = '1'

　　EOF

　　vim main.cf

　　smtpd_sender_login_maps =

　　mysql:/etc/postfix/mysql_virtual_sender_maps.cf

　　smtpd_sender_restrictions =

　　permit_mynetworks,

　　reject_sender_login_mismatch,

　　reject_authenticated_sender_login_mismatch,

　　reject_unauthenticated_sender_login_mismatch使配置生效

　　postfix reload