Django + Postfix + Gmail + openDKIM -avamis > dkim = 中性（正文哈希未验证）

Question

我已关注this tutorial 在 Debian 7 wheezy 上配置 DKIM 和 Postfix。这些说明几乎是 interwebz 上的标准。

我正在使用 Gmail 使用我自己的域发送和接收电子邮件。我跟着this instructions 实现了这一目标。

我的问题

我可以发送和接收电子邮件，但我无法通过 DKIM 测试（至少使用 Gmail）。经过一段时间的搜索和挣扎，我得出的结论是，我的问题是因为我的邮件获得了多个 DKIM 签名（请参阅下面的 mail.log）。根据 DKIM 指令，这足以让 DKIM 失败。

但在阅读了有关如何解决多签名问题的信息后，我发现所有这些解决方案都指的是安装了“amavis”。事情是......我没有安装它！

无论如何，这些解决方案都提到了更改与 master.cnf 和/或 main.cfn 中的 milters 相关的后缀配置。例如，将其添加到“receive_override_options”（同样，我没有那个变量，因为我没有安装 amavis）应该可以解决问题：

receive_override_options=no_unknown_recipient_checks,no_header_body_checks,no_milters

或者，另一种解决方案是在 main.cf 中注释全局设置...

#smtpd_milters = inet:localhost:12301
#non_smtpd_milters = inet:localhost:12301

...然后将 milter 指令添加到“smtpd”和后 amavis 服务 分别用于入站身份验证和出站签名：

# inbound messages from internet
# will be authenticated by OpenDKIM milter on port 12301
smtp      inet  n       -       -       -       -       smtpd
 .......
  -o smtpd_milters=inet:localhost:12301

# outbound messages have been through amavis
# will be signed by OpenDKIM milter on port 12301
127.0.0.1:10025 inet    n       -       -       -       -       smtpd
 .......
  -o smtpd_milters=inet:localhost:12301

唉，这些都不适合我，因为我没有安装 amavis。所以我认为正在发生的事情是 Django 层以某种方式与 Postfix 混淆，因此电子邮件得到了由 opendkim 签名的两次 DKIM（参见下面的 mail.log）。

这是 Gmail 回复：

ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816;
        h=message-id:date:to:from:subject:content-transfer-encoding
         :mime-version:dkim-signature:arc-authentication-results;
        bh=rFbauTH/rtd1+kK8TxaFUe3HjRRJjkoamWIx2IdGVtM=;
        b=MKXMH0s3t4rJtnbq1NTX/3Pu7WroJ1/QcMEyAMdQQhF4pFM1imdRTA==
ARC-Authentication-Results: i=1; mx.google.com;
       dkim=neutral (body hash did not verify) header.i=@domain.com header.s=mail header.b=X2M3CvND;
       spf=pass (google.com: domain of error@domain.com designates 45.76.171.123 as permitted sender) smtp.mailfrom=error@domain.com

这是我的 mail.log。请注意“DKIM 签名标头添加”是如何执行的两次：一次在 localhost 连接后，另一次在重新连接后执行。

Aug 25 16:12:21 domain postfix/smtpd[29238]: connect from localhost[127.0.0.1]
Aug 25 16:12:21 domain postfix/smtpd[29238]: 745D37D599: client=localhost[127.0.0.1]
Aug 25 16:12:21 domain postfix/cleanup[29243]: 745D37D599: message-id=<20170825161221.28656.25384@localhost>
Aug 25 16:12:21 domain opendkim[27899]: 745D37D599: DKIM-Signature header added (s=mail, d=domain.com)
Aug 25 16:12:21 domain postfix/qmgr[29037]: 745D37D599: from=<error@domain.com>, size=44876, nrcpt=1 (queue active)
Aug 25 16:12:21 domain postfix/smtpd[29238]: disconnect from localhost[127.0.0.1]
Aug 25 16:12:21 domain postfix/smtpd[29238]: connect from localhost[127.0.0.1]
Aug 25 16:12:21 domain postfix/smtpd[29238]: 8E8287D5C0: client=localhost[127.0.0.1]
Aug 25 16:12:21 domain postfix/cleanup[29243]: 8E8287D5C0: message-id=<20170825161221.28656.34673@localhost>
Aug 25 16:12:21 domain opendkim[27899]: 8E8287D5C0: DKIM-Signature header added (s=mail, d=domain.com)
Aug 25 16:12:21 domain postfix/qmgr[29037]: 8E8287D5C0: from=<error@domain.com>, size=44876, nrcpt=1 (queue active)
Aug 25 16:12:21 domain postfix/smtpd[29238]: disconnect from localhost[127.0.0.1]
Aug 25 16:12:22 domain postfix/smtp[29244]: 745D37D599: to=<user@gmail.com>, orig_to=<error@domain.com>, relay=gmail-smtp-in.l.google.com[74.125.28.26]:25, delay=0.61, delays=0.05/0.02/0.12/0.41, dsn=2.0.0, status=sent (250 2.0.0 OK 1503677542 r29si5009980pfd.56 - gsmtp)
Aug 25 16:12:22 domain postfix/qmgr[29037]: 745D37D599: removed
Aug 25 16:12:22 domain postfix/smtp[29245]: 8E8287D5C0: to=<user@gmail.com>, orig_to=<error@domain.com>, relay=gmail-smtp-in.l.google.com[74.125.28.26]:25, delay=0.51, delays=0.05/0.01/0.09/0.36, dsn=2.0.0, status=sent (250 2.0.0 OK 1503677542 t196si4944733pgc.158 - gsmtp)
Aug 25 16:12:22 domain postfix/qmgr[29037]: 8E8287D5C0: removed

可能在 mail.log 中看到的 localhost 用户是在我的 Django 的 settings.py 中设置的用户

EMAIL_BACKEND = 'django.core.mail.backends.smtp.EmailBackend'
EMAIL_HOST = 'localhost'
EMAIL_PORT = 25
EMAIL_HOST_USER = ''
EMAIL_HOST_PASSWORD = ''
EMAIL_USE_TLS = False

我的 /etc/postfix/master.cf

smtp      inet  n       -       -       -       -       smtpd
pickup    fifo  n       -       -       60      1       pickup
cleanup   unix  n       -       -       -       0       cleanup
qmgr      fifo  n       -       n       300     1       qmgr
tlsmgr    unix  -       -       -       1000?   1       tlsmgr
rewrite   unix  -       -       -       -       -       trivial-rewrite
bounce    unix  -       -       -       -       0       bounce
defer     unix  -       -       -       -       0       bounce
trace     unix  -       -       -       -       0       bounce
verify    unix  -       -       -       -       1       verify
flush     unix  n       -       -       1000?   0       flush
proxymap  unix  -       -       n       -       -       proxymap
proxywrite unix -       -       n       -       1       proxymap
smtp      unix  -       -       -       -       -       smtp
relay     unix  -       -       -       -       -       smtp
showq     unix  n       -       -       -       -       showq
error     unix  -       -       -       -       -       error
retry     unix  -       -       -       -       -       error
discard   unix  -       -       -       -       -       discard
local     unix  -       n       n       -       -       local
virtual   unix  -       n       n       -       -       virtual
lmtp      unix  -       -       -       -       -       lmtp
anvil     unix  -       -       -       -       1       anvil
scache    unix  -       -       -       -       1       scache
maildrop  unix  -       n       n       -       -       pipe
  flags=DRhu user=vmail argv=/usr/bin/maildrop -d ${recipient}
uucp      unix  -       n       n       -       -       pipe
  flags=Fqhu user=uucp argv=uux -r -n -z -a$sender - $nexthop!rmail ($recipient)
ifmail    unix  -       n       n       -       -       pipe
  flags=F user=ftn argv=/usr/lib/ifmail/ifmail -r $nexthop ($recipient)
bsmtp     unix  -       n       n       -       -       pipe
  flags=Fq. user=bsmtp argv=/usr/lib/bsmtp/bsmtp -t$nexthop -f$sender $recipient
scalemail-backend unix  -   n   n   -   2   pipe
  flags=R user=scalemail argv=/usr/lib/scalemail/bin/scalemail-store ${nexthop} ${user} ${extension}
mailman   unix  -       n       n       -       -       pipe
  flags=FR user=list argv=/usr/lib/mailman/bin/postfix-to-mailman.py
  ${nexthop} ${user}

我的 /etc/postfix/main.cf

smtpd_banner = $myhostname ESMTP $mail_name (Debian/GNU)
biff = no
append_dot_mydomain = no
readme_directory = no
smtpd_tls_cert_file = /etc/postfix/server.pem
smtpd_tls_key_file = $smtpd_tls_cert_file
smtpd_use_tls=yes
smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache
smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache
myhostname = automatones.com
alias_maps = hash:/etc/aliases
alias_database = hash:/etc/aliases
myorigin = /etc/mailname
mydestination = localhost.localdomain, localhost, domain.com
relayhost = 
mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128
mailbox_size_limit = 0
recipient_delimiter = +
inet_interfaces = all
inet_protocols = ipv4
virtual_alias_maps = hash:/etc/postfix/virtual
smtpd_sasl_type = dovecot
smtpd_sasl_auth_enable = yes
queue_directory = /var/spool/postfix
smtpd_sasl_path = private/auth
smtpd_sasl_auth_enable = yes
smtpd_sasl_type = dovecot
milter_protocol = 2
milter_default_action = accept
smtpd_milters = inet:localhost:12301
non_smtpd_milters = inet:localhost:12301
virtual_alias_domains = domain.com

我的http://dkimvalidator.com/results：

SpamAssassin Score: 0.472
Message is NOT marked as spam
Points breakdown: 
-0.0 SPF_HELO_PASS          SPF: HELO matches SPF record
 0.1 DKIM_SIGNED            Message has a DKIM or DK signature, not necessarily valid
 0.4 RDNS_DYNAMIC           Delivered to internal network by host with
                            dynamic-looking rDNS
 0.0 T_DKIM_INVALID         DKIM-Signature header exists but is not valid

那么我该如何调整后缀配置以不触发我在 mail.log 中看到的多个 DKMI 标头签名添加？或者如何配置 Django 设置以不触发此连接和重新连接行为？

欢迎任何指点、想法或建议！

编辑：我找到了this note in the README file of OPENDMARC 我可以从中得到解决方案吗？如果是这样，我该如何开始实施它？

(c) If you have a content filter in master.cf that feeds it back into a different smtpd process, you should alter the second smtpd process in     master.cf to contain '-o receive_override_options=no_milters' to    prevent messages being signed or verified twice.  For tips on avoiding DKIM signature breakage, see:    http://www.postfix.org/MILTER_README.html#workarounds

Answer 1

在经过几次尝试和错误之后，我在不久前设法解决了这个问题。问题是我不记得我到底做了什么来解决它。我正在玩几个参数 - 有时同时 - 没有保持任何轨道（我的坏）。然而，在某些时候一切都奏效了！

这是我的配置文件。希望他们可以指导/帮助某人。

/etc/postfix/master.cf

#
# Postfix master process configuration file.  For details on the format
# of the file, see the master(5) manual page (command: "man 5 master").
#
# Do not forget to execute "postfix reload" after editing this file.
#
# ==========================================================================
# service type  private unpriv  chroot  wakeup  maxproc command + args
#               (yes)   (yes)   (yes)   (never) (100)
# ==========================================================================
smtp      inet  n       -       -       -       -       smtpd
  -o content_filter=spamassassin
#smtp      inet  n       -       -       -       1       postscreen
#smtpd     pass  -       -       -       -       -       smtpd
#dnsblog   unix  -       -       -       -       0       dnsblog
#tlsproxy  unix  -       -       -       -       0       tlsproxy
submission inet n       -       -       -       -       smtpd
  -o syslog_name=postfix/submission
  -o smtpd_tls_security_level=encrypt
  -o smtpd_sasl_auth_enable=yes
  -o smtpd_recipient_restrictions=permit_mynetworks,permit_sasl_authenticated,reject
  -o milter_macro_daemon_name=ORIGINATING
  -o content_filter=spamassassin
  -o smtpd_sasl_type=dovecot
  -o smtpd_sasl_path=private/auth
smtps     inet  n       -       -       -       -       smtpd
  -o syslog_name=postfix/smtps
  -o smtpd_tls_wrappermode=yes
  -o smtpd_sasl_auth_enable=yes
  -o smtpd_client_restrictions=permit_sasl_authenticated,reject
  -o milter_macro_daemon_name=ORIGINATING
  -o content_filter=spamassassin
#628       inet  n       -       -       -       -       qmqpd
pickup    fifo  n       -       -       60      1       pickup
cleanup   unix  n       -       -       -       0       cleanup
qmgr      fifo  n       -       n       300     1       qmgr
#qmgr     fifo  n       -       n       300     1       oqmgr
tlsmgr    unix  -       -       -       1000?   1       tlsmgr
rewrite   unix  -       -       -       -       -       trivial-rewrite
bounce    unix  -       -       -       -       0       bounce
defer     unix  -       -       -       -       0       bounce
trace     unix  -       -       -       -       0       bounce
verify    unix  -       -       -       -       1       verify
flush     unix  n       -       -       1000?   0       flush
proxymap  unix  -       -       n       -       -       proxymap
proxywrite unix -       -       n       -       1       proxymap
smtp      unix  -       -       -       -       -       smtp
relay     unix  -       -       -       -       -       smtp
#       -o smtp_helo_timeout=5 -o smtp_connect_timeout=5
showq     unix  n       -       -       -       -       showq
error     unix  -       -       -       -       -       error
retry     unix  -       -       -       -       -       error
discard   unix  -       -       -       -       -       discard
local     unix  -       n       n       -       -       local
virtual   unix  -       n       n       -       -       virtual
lmtp      unix  -       -       -       -       -       lmtp
anvil     unix  -       -       -       -       1       anvil
scache    unix  -       -       -       -       1       scache
#
# ====================================================================
# Interfaces to non-Postfix software. Be sure to examine the manual
# pages of the non-Postfix software to find out what options it wants.
#
# Many of the following services use the Postfix pipe(8) delivery
# agent.  See the pipe(8) man page for information about ${recipient}
# and other message envelope options.
# ====================================================================
#
# maildrop. See the Postfix MAILDROP_README file for details.
# Also specify in main.cf: maildrop_destination_recipient_limit=1
#
maildrop  unix  -       n       n       -       -       pipe
  flags=DRhu user=vmail argv=/usr/bin/maildrop -d ${recipient}
#
# ====================================================================
#
# Recent Cyrus versions can use the existing "lmtp" master.cf entry.
#
# Specify in cyrus.conf:
#   lmtp    cmd="lmtpd -a" listen="localhost:lmtp" proto=tcp4
#
# Specify in main.cf one or more of the following:
#  mailbox_transport = lmtp:inet:localhost
#  virtual_transport = lmtp:inet:localhost
#
# ====================================================================
#
# Cyrus 2.1.5 (Amos Gouaux)
# Also specify in main.cf: cyrus_destination_recipient_limit=1
#
#cyrus     unix  -       n       n       -       -       pipe
#  user=cyrus argv=/cyrus/bin/deliver -e -r ${sender} -m ${extension} ${user}
#
# ====================================================================
# Old example of delivery via Cyrus.
#
#old-cyrus unix  -       n       n       -       -       pipe
#  flags=R user=cyrus argv=/cyrus/bin/deliver -e -m ${extension} ${user}
#
# ====================================================================
#
# See the Postfix UUCP_README file for configuration details.
#
uucp      unix  -       n       n       -       -       pipe
  flags=Fqhu user=uucp argv=uux -r -n -z -a$sender - $nexthop!rmail ($recipient)
#
# Other external delivery methods.
#
ifmail    unix  -       n       n       -       -       pipe
  flags=F user=ftn argv=/usr/lib/ifmail/ifmail -r $nexthop ($recipient)
bsmtp     unix  -       n       n       -       -       pipe
  flags=Fq. user=bsmtp argv=/usr/lib/bsmtp/bsmtp -t$nexthop -f$sender $recipient
scalemail-backend unix  -   n   n   -   2   pipe
  flags=R user=scalemail argv=/usr/lib/scalemail/bin/scalemail-store ${nexthop} ${user} ${extension}
mailman   unix  -       n       n       -       -       pipe
  flags=FR user=list argv=/usr/lib/mailman/bin/postfix-to-mailman.py
  ${nexthop} ${user}

dovecot   unix  -       n       n       -       -       pipe
  flags=DRhu user=email:email argv=/usr/lib/dovecot/deliver -f ${sender} -d ${recipient}

policy-spf  unix  -     n       n       -       -       spawn
     user=nobody argv=/usr/bin/policyd-spf

spamassassin unix -     n       n       -       -       pipe
  user=debian-spamd argv=/usr/bin/spamc -f -e /usr/sbin/sendmail -oi -f ${sender} ${recipient}

/etc/postfix/main.cf

# See /usr/share/postfix/main.cf.dist for a commented, more complete version


# Debian specific:  Specifying a file name will cause the first
# line of that file to be used as the name.  The Debian default
# is /etc/mailname.
#myorigin = /etc/mailname

smtpd_banner = $myhostname ESMTP $mail_name (Debian/GNU)
biff = no

# appending .domain is the MUA's job.
append_dot_mydomain = no

# Uncomment the next line to generate "delayed mail" warnings
#delay_warning_time = 4h

readme_directory = no

# Network information
myhostname = mail.mysite.com
mydomain = mysite.com
myorigin = /etc/mailname
mydestination = $myhostname, $mydomain, localhost.localdomain, localhost
relayhost = 
mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128
mailbox_size_limit = 0
recipient_delimiter = +
inet_interfaces = all

# Local alias map
alias_maps = hash:/etc/aliases
alias_database = hash:/etc/aliases

queue_directory=/var/spool/postfix

# SSL
smtpd_tls_cert_file = /etc/letsencrypt/live/mail.mysite.com/fullchain.pem
smtpd_tls_key_file = /etc/letsencrypt/live/mail.mysite.com/privkey.pem
smtpd_use_tls=yes
smtpd_tls_auth_only=yes
smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache
smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache
smtpd_tls_security_level = may
smtp_tls_security_level = may
smtp_tls_loglevel = 1
smtpd_tls_loglevel = 1
smtpd_tls_protocols = !SSLv2, !SSLv3

# SPF
policy-spf_time_limit = 3600s

# https://www.digitalocean.com/community/tutorials/how-to-set-up-a-postfix-e-mail-server-with-dovecot
#local_recipient_maps = proxy:unix:passwd.byname $alias_maps

# Virtual alias mapping
virtual_alias_domains = $mydomain
virtual_alias_maps = hash:/etc/postfix/virtual

# Mail will be stored in users ~/Maildir directories
home_mailbox = Maildir/
mailbox_command =

# From http://wiki2.dovecot.org/HowTo/PostfixAndDovecotSASL
smtpd_sasl_type = dovecot
smtpd_sasl_path = private/auth
smtpd_sasl_auth_enable = yes

# DKIM & DMARC
milter_default_action = accept
milter_protocol = 6
smtpd_milters = inet:127.0.0.1:12345, inet:127.0.0.1:8893
non_smtpd_milters = inet:127.0.0.1:12345, inet:127.0.0.1:8893

# Require a valid HELO or EHLO command with a fully qualified domain name to stop common spambots 
smtpd_helo_required = yes
smtpd_helo_restrictions = reject_non_fqdn_helo_hostname,reject_invalid_helo_hostname,reject_unknown_helo_hostname

# Disable the VRFY command 
disable_vrfy_command = yes

# Reject message to allow Postfix to log recipient address information when the connected client breaks any of the reject rules
smtpd_delay_reject = yes

# Reject connections from made up addresses that do not use a FQDN or don't exist. Add external spam filters like Spamhaus or CBL blacklists
# Also add SPF policy (after reject_unauth_destination and after permit_sasl_authenticated)
smtpd_recipient_restrictions = permit_sasl_authenticated,permit_mynetworks,reject_unauth_destination,check_policy_service unix:private/policy-spf,reject_invalid_hostname,reject_non_fqdn_hostname,reject_non_fqdn_sender,reject_non_fqdn_recipient,reject_unknown_sender_domain,reject_rbl_client sbl.spamhaus.org,reject_rbl_client cbl.abuseat.org

# https://serverfault.com/questions/559088/postfix-not-accepting-relay-from-localhost
default_transport = smtp
relay_transport = relay