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postfix-3.10-20250126-nonprod

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Wietse Z Venema 2025-01-26 00:00:00 -05:00 committed by Viktor Dukhovni
parent c378e47a69
commit 137e70673b
12 changed files with 449 additions and 434 deletions
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36
postfix/HISTORY
View File

@ -28952,8 +28952,28 @@ Apologies for any names omitted.
Completed: simplify the code in cleanup_envelope_test.c.
Completed: REQUIRETLS support can be disabled in the Postfix
SMTP/LMTP client with "{ -o requiretls_enable = no }". This
is recommended for a perimeter MTA that hands off mail to
internal servers that may not support REQUIRETLS.
Completed: simplified cleanup_envelope_test implementation.
TODO:
Add a log-only mode for REQUIRETLS, so that one can find out
how much would break. Maybe make it a map, so that different
sites can have different enforcement levels.
If we support log-only REQUIRETLS, then don't panic ("can't
happen") when the code reaches a point that can't be reached
when REQUIRETLS is actually enforced.
Encapsulate the sendopts-to-cleanup-flags mapping.
How do we make it work with multi-instance SMTP-based content
filters? How is this different from the single-instance case?
What REQUIRETLS expectations can we enforce when delivering
over a UNIX-domain channel? The SMTP/LMTP client currently
implements the same behavior as for TCP, except that
@ -28990,17 +29010,13 @@ TODO:
not require that the LMTP server announces REQUIRETLS
support.
- Perimeter MTA configuration: disable REQUIRETLS on the
inbound relay transport when internal infrastructure may
not be suitable for REQUIRETLS enforcement.
If a message contains "TLS-Required: no", should a bounce
message also contain this header?
If the Postfix SMTP server accepted REQUIRETLS, should that
stay in effect if, before the message is forwarded, the
configuration is changed to "requiretls_enable = no"? Same
for "postsuper -r".
Ditto for "tls_required_enable = no" and "TLS-Required:
no".
Simplify the cleanup_envelope_test. Write the initial SIZE
record to /dev/null, don't call cleanup_final(), and verify
the value of state->sendopts.
no". The header is provided by the sender, and enforcement
is up the Postfix SMTP client.

372
postfix/html/lmtp.8.html
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@ -143,11 +143,9 @@ SMTP(8) SMTP(8)
<b>X</b> Indicates that the delivery is final. This flag affects
the status reported in "success" DSN (delivery status
notification) messages, and changes it from "relayed"
into "delivered". The flag also suppresses the require-
ment that the remote server announces REQUIRETLS support.
into "delivered".
This feature is available as of Postfix 3.5; REQUIRETLS
support was introduced with Postfix 3.10.
This feature is available as of Postfix 3.5.
<b><a name="security">SECURITY</a></b>
The SMTP+LMTP client is moderately security-sensitive. It talks to SMTP
@ -179,34 +177,34 @@ SMTP(8) SMTP(8)
<a href="https://tools.ietf.org/html/rfc8689">RFC 8689</a> (SMTP REQUIRETLS extension)
<b><a name="diagnostics">DIAGNOSTICS</a></b>
Problems and transactions are logged to <b>syslogd</b>(8) or <a href="postlogd.8.html"><b>postlogd</b>(8)</a>.
Corrupted message files are marked so that the queue manager can move
Problems and transactions are logged to <b>syslogd</b>(8) or <a href="postlogd.8.html"><b>postlogd</b>(8)</a>.
Corrupted message files are marked so that the queue manager can move
them to the <b>corrupt</b> queue for further inspection.
Depending on the setting of the <b><a href="postconf.5.html#notify_classes">notify_classes</a></b> parameter, the postmas-
Depending on the setting of the <b><a href="postconf.5.html#notify_classes">notify_classes</a></b> parameter, the postmas-
ter is notified of bounces, protocol problems, and of other trouble.
<b><a name="bugs">BUGS</a></b>
SMTP and LMTP connection reuse for TLS (without closing the SMTP or
SMTP and LMTP connection reuse for TLS (without closing the SMTP or
LMTP connection) is not supported before Postfix 3.4.
SMTP and LMTP connection reuse assumes that SASL credentials are valid
SMTP and LMTP connection reuse assumes that SASL credentials are valid
for all destinations that map onto the same IP address and TCP port.
<b><a name="configuration_parameters">CONFIGURATION PARAMETERS</a></b>
Postfix versions 2.3 and later implement the SMTP and LMTP client with
the same program, and choose the protocol and configuration parameters
Postfix versions 2.3 and later implement the SMTP and LMTP client with
the same program, and choose the protocol and configuration parameters
based on the process name, <b>smtp</b> or <b>lmtp</b>.
Most smtp_<i>xxx</i> configuration parameters have an lmtp_<i>xxx</i> "mirror" param-
eter for the equivalent LMTP feature. This document describes only
eter for the equivalent LMTP feature. This document describes only
those LMTP-related parameters that aren't simply "mirror" parameters.
Changes to <a href="postconf.5.html"><b>main.cf</b></a> are picked up automatically, as <a href="smtp.8.html"><b>smtp</b>(8)</a> processes
Changes to <a href="postconf.5.html"><b>main.cf</b></a> are picked up automatically, as <a href="smtp.8.html"><b>smtp</b>(8)</a> processes
run for only a limited amount of time. Use the command "<b>postfix reload</b>"
to speed up a change.
The text below provides only a parameter summary. See <a href="postconf.5.html"><b>postconf</b>(5)</a> for
The text below provides only a parameter summary. See <a href="postconf.5.html"><b>postconf</b>(5)</a> for
more details including examples.
<b><a name="compatibility_controls">COMPATIBILITY CONTROLS</a></b>
@ -227,8 +225,8 @@ SMTP(8) SMTP(8)
will send via SMTP.
<b><a href="postconf.5.html#smtp_pix_workaround_delay_time">smtp_pix_workaround_delay_time</a> (10s)</b>
How long the Postfix SMTP client pauses before sending
".&lt;CR&gt;&lt;LF&gt;" in order to work around the PIX firewall
How long the Postfix SMTP client pauses before sending
".&lt;CR&gt;&lt;LF&gt;" in order to work around the PIX firewall
"&lt;CR&gt;&lt;LF&gt;.&lt;CR&gt;&lt;LF&gt;" bug.
<b><a href="postconf.5.html#smtp_pix_workaround_threshold_time">smtp_pix_workaround_threshold_time</a> (500s)</b>
@ -237,19 +235,19 @@ SMTP(8) SMTP(8)
delivery through firewalls with "smtp fixup" mode turned on.
<b><a href="postconf.5.html#smtp_pix_workarounds">smtp_pix_workarounds</a> (disable_esmtp, delay_dotcrlf)</b>
A list that specifies zero or more workarounds for CISCO PIX
A list that specifies zero or more workarounds for CISCO PIX
firewall bugs.
<b><a href="postconf.5.html#smtp_pix_workaround_maps">smtp_pix_workaround_maps</a> (empty)</b>
Lookup tables, indexed by the remote SMTP server address, with
Lookup tables, indexed by the remote SMTP server address, with
per-destination workarounds for CISCO PIX firewall bugs.
<b><a href="postconf.5.html#smtp_quote_rfc821_envelope">smtp_quote_rfc821_envelope</a> (yes)</b>
Quote addresses in Postfix SMTP client MAIL FROM and RCPT TO
Quote addresses in Postfix SMTP client MAIL FROM and RCPT TO
commands as required by <a href="https://tools.ietf.org/html/rfc5321">RFC 5321</a>.
<b><a href="postconf.5.html#smtp_reply_filter">smtp_reply_filter</a> (empty)</b>
A mechanism to transform replies from remote SMTP servers one
A mechanism to transform replies from remote SMTP servers one
line at a time.
<b><a href="postconf.5.html#smtp_skip_5xx_greeting">smtp_skip_5xx_greeting</a> (yes)</b>
@ -261,68 +259,68 @@ SMTP(8) SMTP(8)
Available in Postfix version 2.0 and earlier:
<b><a href="postconf.5.html#smtp_skip_4xx_greeting">smtp_skip_4xx_greeting</a> (yes)</b>
Skip SMTP servers that greet with a 4XX status code (go away,
Skip SMTP servers that greet with a 4XX status code (go away,
try again later).
Available in Postfix version 2.2 and later:
<b><a href="postconf.5.html#smtp_discard_ehlo_keyword_address_maps">smtp_discard_ehlo_keyword_address_maps</a> (empty)</b>
Lookup tables, indexed by the remote SMTP server address, with
case insensitive lists of EHLO keywords (pipelining, starttls,
Lookup tables, indexed by the remote SMTP server address, with
case insensitive lists of EHLO keywords (pipelining, starttls,
auth, etc.) that the Postfix SMTP client will ignore in the EHLO
response from a remote SMTP server.
<b><a href="postconf.5.html#smtp_discard_ehlo_keywords">smtp_discard_ehlo_keywords</a> (empty)</b>
A case insensitive list of EHLO keywords (pipelining, starttls,
A case insensitive list of EHLO keywords (pipelining, starttls,
auth, etc.) that the Postfix SMTP client will ignore in the EHLO
response from a remote SMTP server.
<b><a href="postconf.5.html#smtp_generic_maps">smtp_generic_maps</a> (empty)</b>
Optional lookup tables that perform address rewriting in the
Postfix SMTP client, typically to transform a locally valid
address into a globally valid address when sending mail across
Optional lookup tables that perform address rewriting in the
Postfix SMTP client, typically to transform a locally valid
address into a globally valid address when sending mail across
the Internet.
Available in Postfix version 2.2.9 and later:
<b><a href="postconf.5.html#smtp_cname_overrides_servername">smtp_cname_overrides_servername</a> (version dependent)</b>
When the remote SMTP servername is a DNS CNAME, replace the
servername with the result from CNAME expansion for the purpose
of logging, SASL password lookup, TLS policy decisions, or TLS
When the remote SMTP servername is a DNS CNAME, replace the
servername with the result from CNAME expansion for the purpose
of logging, SASL password lookup, TLS policy decisions, or TLS
certificate verification.
Available in Postfix version 2.3 and later:
<b><a href="postconf.5.html#lmtp_discard_lhlo_keyword_address_maps">lmtp_discard_lhlo_keyword_address_maps</a> (empty)</b>
Lookup tables, indexed by the remote LMTP server address, with
case insensitive lists of LHLO keywords (pipelining, starttls,
Lookup tables, indexed by the remote LMTP server address, with
case insensitive lists of LHLO keywords (pipelining, starttls,
auth, etc.) that the Postfix LMTP client will ignore in the LHLO
response from a remote LMTP server.
<b><a href="postconf.5.html#lmtp_discard_lhlo_keywords">lmtp_discard_lhlo_keywords</a> (empty)</b>
A case insensitive list of LHLO keywords (pipelining, starttls,
A case insensitive list of LHLO keywords (pipelining, starttls,
auth, etc.) that the Postfix LMTP client will ignore in the LHLO
response from a remote LMTP server.
Available in Postfix version 2.4.4 and later:
<b><a href="postconf.5.html#send_cyrus_sasl_authzid">send_cyrus_sasl_authzid</a> (no)</b>
When authenticating to a remote SMTP or LMTP server with the
default setting "no", send no SASL authoriZation ID (authzid);
send only the SASL authentiCation ID (authcid) plus the auth-
When authenticating to a remote SMTP or LMTP server with the
default setting "no", send no SASL authoriZation ID (authzid);
send only the SASL authentiCation ID (authcid) plus the auth-
cid's password.
Available in Postfix version 2.5 and later:
<b><a href="postconf.5.html#smtp_header_checks">smtp_header_checks</a> (empty)</b>
Restricted <a href="header_checks.5.html"><b>header_checks</b>(5)</a> tables for the Postfix SMTP client.
Restricted <a href="header_checks.5.html"><b>header_checks</b>(5)</a> tables for the Postfix SMTP client.
<b><a href="postconf.5.html#smtp_mime_header_checks">smtp_mime_header_checks</a> (empty)</b>
Restricted <b><a href="postconf.5.html#mime_header_checks">mime_header_checks</a></b>(5) tables for the Postfix SMTP
Restricted <b><a href="postconf.5.html#mime_header_checks">mime_header_checks</a></b>(5) tables for the Postfix SMTP
client.
<b><a href="postconf.5.html#smtp_nested_header_checks">smtp_nested_header_checks</a> (empty)</b>
Restricted <b><a href="postconf.5.html#nested_header_checks">nested_header_checks</a></b>(5) tables for the Postfix SMTP
Restricted <b><a href="postconf.5.html#nested_header_checks">nested_header_checks</a></b>(5) tables for the Postfix SMTP
client.
<b><a href="postconf.5.html#smtp_body_checks">smtp_body_checks</a> (empty)</b>
@ -331,7 +329,7 @@ SMTP(8) SMTP(8)
Available in Postfix version 2.6 and later:
<b><a href="postconf.5.html#tcp_windowsize">tcp_windowsize</a> (0)</b>
An optional workaround for routers that break TCP window scal-
An optional workaround for routers that break TCP window scal-
ing.
Available in Postfix version 2.8 and later:
@ -342,16 +340,16 @@ SMTP(8) SMTP(8)
Available in Postfix version 2.9 - 3.6:
<b><a href="postconf.5.html#smtp_per_record_deadline">smtp_per_record_deadline</a> (no)</b>
Change the behavior of the smtp_*_timeout time limits, from a
time limit per read or write system call, to a time limit to
send or receive a complete record (an SMTP command line, SMTP
response line, SMTP message content line, or TLS protocol mes-
Change the behavior of the smtp_*_timeout time limits, from a
time limit per read or write system call, to a time limit to
send or receive a complete record (an SMTP command line, SMTP
response line, SMTP message content line, or TLS protocol mes-
sage).
Available in Postfix version 2.9 and later:
<b><a href="postconf.5.html#smtp_send_dummy_mail_auth">smtp_send_dummy_mail_auth</a> (no)</b>
Whether or not to append the "AUTH=&lt;&gt;" option to the MAIL FROM
Whether or not to append the "AUTH=&lt;&gt;" option to the MAIL FROM
command in SASL-authenticated SMTP sessions.
Available in Postfix version 2.11 and later:
@ -362,7 +360,7 @@ SMTP(8) SMTP(8)
Available in Postfix version 3.0 and later:
<b><a href="postconf.5.html#smtp_delivery_status_filter">smtp_delivery_status_filter</a> ($<a href="postconf.5.html#default_delivery_status_filter">default_delivery_status_filter</a>)</b>
Optional filter for the <a href="smtp.8.html"><b>smtp</b>(8)</a> delivery agent to change the
Optional filter for the <a href="smtp.8.html"><b>smtp</b>(8)</a> delivery agent to change the
delivery status code or explanatory text of successful or unsuc-
cessful deliveries.
@ -372,38 +370,38 @@ SMTP(8) SMTP(8)
Available in Postfix version 3.3 and later:
<b><a href="postconf.5.html#smtp_balance_inet_protocols">smtp_balance_inet_protocols</a> (yes)</b>
When a remote destination resolves to a combination of IPv4 and
When a remote destination resolves to a combination of IPv4 and
IPv6 addresses, ensure that the Postfix SMTP client can try both
address types before it runs into the <a href="postconf.5.html#smtp_mx_address_limit">smtp_mx_address_limit</a>.
Available in Postfix 3.5 and later:
<b><a href="postconf.5.html#info_log_address_format">info_log_address_format</a> (external)</b>
The email address form that will be used in non-debug logging
The email address form that will be used in non-debug logging
(info, warning, etc.).
Available in Postfix 3.6 and later:
<b><a href="postconf.5.html#dnssec_probe">dnssec_probe</a> (ns:.)</b>
The DNS query type (default: "ns") and DNS query name (default:
The DNS query type (default: "ns") and DNS query name (default:
".") that Postfix may use to determine whether DNSSEC validation
is available.
<b><a href="postconf.5.html#known_tcp_ports">known_tcp_ports</a> (lmtp=24, smtp=25, smtps=submissions=465, submis-</b>
<b><a href="postconf.5.html#known_tcp_ports">known_tcp_ports</a> (lmtp=24, smtp=25, smtps=submissions=465, submis-</b>
<b>sion=587)</b>
Optional setting that avoids lookups in the <b>services</b>(5) data-
Optional setting that avoids lookups in the <b>services</b>(5) data-
base.
Available in Postfix version 3.7 and later:
<b><a href="postconf.5.html#smtp_per_request_deadline">smtp_per_request_deadline</a> (no)</b>
Change the behavior of the smtp_*_timeout time limits, from a
time limit per plaintext or TLS read or write call, to a com-
bined time limit for sending a complete SMTP request and for
Change the behavior of the smtp_*_timeout time limits, from a
time limit per plaintext or TLS read or write call, to a com-
bined time limit for sending a complete SMTP request and for
receiving a complete SMTP response.
<b><a href="postconf.5.html#smtp_min_data_rate">smtp_min_data_rate</a> (500)</b>
The minimum plaintext data transfer rate in bytes/second for
The minimum plaintext data transfer rate in bytes/second for
DATA requests, when deadlines are enabled with
<a href="postconf.5.html#smtp_per_request_deadline">smtp_per_request_deadline</a>.
@ -413,16 +411,16 @@ SMTP(8) SMTP(8)
Available in Postfix version 3.8 and later:
<b><a href="postconf.5.html#use_srv_lookup">use_srv_lookup</a> (empty)</b>
Enables discovery for the specified service(s) using DNS SRV
Enables discovery for the specified service(s) using DNS SRV
records.
<b><a href="postconf.5.html#ignore_srv_lookup_error">ignore_srv_lookup_error</a> (no)</b>
When SRV record lookup fails, fall back to MX or IP address
When SRV record lookup fails, fall back to MX or IP address
lookup as if SRV record lookup was not enabled.
<b><a href="postconf.5.html#allow_srv_lookup_fallback">allow_srv_lookup_fallback</a> (no)</b>
When SRV record lookup fails or no SRV record exists, fall back
to MX or IP address lookup as if SRV record lookup was not
When SRV record lookup fails or no SRV record exists, fall back
to MX or IP address lookup as if SRV record lookup was not
enabled.
<b><a name="mime_processing_controls">MIME PROCESSING CONTROLS</a></b>
@ -441,7 +439,7 @@ SMTP(8) SMTP(8)
Available in Postfix version 2.1 and later:
<b><a href="postconf.5.html#smtp_send_xforward_command">smtp_send_xforward_command</a> (no)</b>
Send the non-standard XFORWARD command when the Postfix SMTP
Send the non-standard XFORWARD command when the Postfix SMTP
server EHLO response announces XFORWARD support.
<b><a name="sasl_authentication_controls">SASL AUTHENTICATION CONTROLS</a></b>
@ -449,88 +447,88 @@ SMTP(8) SMTP(8)
Enable SASL authentication in the Postfix SMTP client.
<b><a href="postconf.5.html#smtp_sasl_password_maps">smtp_sasl_password_maps</a> (empty)</b>
Optional Postfix SMTP client lookup tables with one user-
name:password entry per sender, remote hostname or next-hop
Optional Postfix SMTP client lookup tables with one user-
name:password entry per sender, remote hostname or next-hop
domain.
<b><a href="postconf.5.html#smtp_sasl_security_options">smtp_sasl_security_options</a> (noplaintext, noanonymous)</b>
Postfix SMTP client SASL security options; as of Postfix 2.3 the
list of available features depends on the SASL client implemen-
list of available features depends on the SASL client implemen-
tation that is selected with <b><a href="postconf.5.html#smtp_sasl_type">smtp_sasl_type</a></b>.
Available in Postfix version 2.2 and later:
<b><a href="postconf.5.html#smtp_sasl_mechanism_filter">smtp_sasl_mechanism_filter</a> (empty)</b>
If non-empty, a Postfix SMTP client filter for the remote SMTP
If non-empty, a Postfix SMTP client filter for the remote SMTP
server's list of offered SASL mechanisms.
Available in Postfix version 2.3 and later:
<b><a href="postconf.5.html#smtp_sender_dependent_authentication">smtp_sender_dependent_authentication</a> (no)</b>
Enable sender-dependent authentication in the Postfix SMTP
client; this is available only with SASL authentication, and
disables SMTP connection caching to ensure that mail from dif-
client; this is available only with SASL authentication, and
disables SMTP connection caching to ensure that mail from dif-
ferent senders will use the appropriate credentials.
<b><a href="postconf.5.html#smtp_sasl_path">smtp_sasl_path</a> (empty)</b>
Implementation-specific information that the Postfix SMTP client
passes through to the SASL plug-in implementation that is
passes through to the SASL plug-in implementation that is
selected with <b><a href="postconf.5.html#smtp_sasl_type">smtp_sasl_type</a></b>.
<b><a href="postconf.5.html#smtp_sasl_type">smtp_sasl_type</a> (cyrus)</b>
The SASL plug-in type that the Postfix SMTP client should use
The SASL plug-in type that the Postfix SMTP client should use
for authentication.
Available in Postfix version 2.5 and later:
<b><a href="postconf.5.html#smtp_sasl_auth_cache_name">smtp_sasl_auth_cache_name</a> (empty)</b>
An optional table to prevent repeated SASL authentication fail-
ures with the same remote SMTP server hostname, username and
An optional table to prevent repeated SASL authentication fail-
ures with the same remote SMTP server hostname, username and
password.
<b><a href="postconf.5.html#smtp_sasl_auth_cache_time">smtp_sasl_auth_cache_time</a> (90d)</b>
The maximal age of an <a href="postconf.5.html#smtp_sasl_auth_cache_name">smtp_sasl_auth_cache_name</a> entry before it
The maximal age of an <a href="postconf.5.html#smtp_sasl_auth_cache_name">smtp_sasl_auth_cache_name</a> entry before it
is removed.
<b><a href="postconf.5.html#smtp_sasl_auth_soft_bounce">smtp_sasl_auth_soft_bounce</a> (yes)</b>
When a remote SMTP server rejects a SASL authentication request
with a 535 reply code, defer mail delivery instead of returning
When a remote SMTP server rejects a SASL authentication request
with a 535 reply code, defer mail delivery instead of returning
mail as undeliverable.
Available in Postfix version 2.9 and later:
<b><a href="postconf.5.html#smtp_send_dummy_mail_auth">smtp_send_dummy_mail_auth</a> (no)</b>
Whether or not to append the "AUTH=&lt;&gt;" option to the MAIL FROM
Whether or not to append the "AUTH=&lt;&gt;" option to the MAIL FROM
command in SASL-authenticated SMTP sessions.
Available in Postfix version 3.9 and later:
<b><a href="postconf.5.html#smtp_sasl_password_result_delimiter">smtp_sasl_password_result_delimiter</a> (:)</b>
The delimiter between username and password in sasl_passwd_maps
The delimiter between username and password in sasl_passwd_maps
lookup results.
<b><a name="tls_support_controls">TLS SUPPORT CONTROLS</a></b>
Detailed information about STARTTLS configuration may be found in the
Detailed information about STARTTLS configuration may be found in the
<a href="TLS_README.html">TLS_README</a> document.
<b><a href="postconf.5.html#smtp_tls_security_level">smtp_tls_security_level</a> (empty)</b>
The default SMTP TLS security level for the Postfix SMTP client.
<b><a href="postconf.5.html#smtp_sasl_tls_security_options">smtp_sasl_tls_security_options</a> ($<a href="postconf.5.html#smtp_sasl_security_options">smtp_sasl_security_options</a>)</b>
The SASL authentication security options that the Postfix SMTP
The SASL authentication security options that the Postfix SMTP
client uses for TLS encrypted SMTP sessions.
<b><a href="postconf.5.html#smtp_starttls_timeout">smtp_starttls_timeout</a> (300s)</b>
Time limit for Postfix SMTP client write and read operations
Time limit for Postfix SMTP client write and read operations
during TLS startup and shutdown handshake procedures.
<b><a href="postconf.5.html#smtp_tls_CAfile">smtp_tls_CAfile</a> (empty)</b>
A file containing CA certificates of root CAs trusted to sign
either remote SMTP server certificates or intermediate CA cer-
A file containing CA certificates of root CAs trusted to sign
either remote SMTP server certificates or intermediate CA cer-
tificates.
<b><a href="postconf.5.html#smtp_tls_CApath">smtp_tls_CApath</a> (empty)</b>
Directory with PEM format Certification Authority certificates
Directory with PEM format Certification Authority certificates
that the Postfix SMTP client uses to verify a remote SMTP server
certificate.
@ -538,7 +536,7 @@ SMTP(8) SMTP(8)
File with the Postfix SMTP client RSA certificate in PEM format.
<b><a href="postconf.5.html#smtp_tls_mandatory_ciphers">smtp_tls_mandatory_ciphers</a> (medium)</b>
The minimum TLS cipher grade that the Postfix SMTP client will
The minimum TLS cipher grade that the Postfix SMTP client will
use with mandatory TLS encryption.
<b><a href="postconf.5.html#smtp_tls_exclude_ciphers">smtp_tls_exclude_ciphers</a> (empty)</b>
@ -546,8 +544,8 @@ SMTP(8) SMTP(8)
client cipher list at all TLS security levels.
<b><a href="postconf.5.html#smtp_tls_mandatory_exclude_ciphers">smtp_tls_mandatory_exclude_ciphers</a> (empty)</b>
Additional list of ciphers or cipher types to exclude from the
Postfix SMTP client cipher list at mandatory TLS security lev-
Additional list of ciphers or cipher types to exclude from the
Postfix SMTP client cipher list at mandatory TLS security lev-
els.
<b><a href="postconf.5.html#smtp_tls_dcert_file">smtp_tls_dcert_file</a> (empty)</b>
@ -563,7 +561,7 @@ SMTP(8) SMTP(8)
Enable additional Postfix SMTP client logging of TLS activity.
<b><a href="postconf.5.html#smtp_tls_note_starttls_offer">smtp_tls_note_starttls_offer</a> (no)</b>
Log the hostname of a remote SMTP server that offers STARTTLS,
Log the hostname of a remote SMTP server that offers STARTTLS,
when TLS is not already enabled for that server.
<b><a href="postconf.5.html#smtp_tls_policy_maps">smtp_tls_policy_maps</a> (empty)</b>
@ -572,14 +570,14 @@ SMTP(8) SMTP(8)
fied, this overrides the obsolete <a href="postconf.5.html#smtp_tls_per_site">smtp_tls_per_site</a> parameter.
<b><a href="postconf.5.html#smtp_tls_mandatory_protocols">smtp_tls_mandatory_protocols</a> (see 'postconf -d' output)</b>
TLS protocols that the Postfix SMTP client will use with manda-
TLS protocols that the Postfix SMTP client will use with manda-
tory TLS encryption.
<b><a href="postconf.5.html#smtp_tls_scert_verifydepth">smtp_tls_scert_verifydepth</a> (9)</b>
The verification depth for remote SMTP server certificates.
<b><a href="postconf.5.html#smtp_tls_secure_cert_match">smtp_tls_secure_cert_match</a> (nexthop, dot-nexthop)</b>
How the Postfix SMTP client verifies the server certificate
How the Postfix SMTP client verifies the server certificate
peername for the "secure" TLS security level.
<b><a href="postconf.5.html#smtp_tls_session_cache_database">smtp_tls_session_cache_database</a> (empty)</b>
@ -587,16 +585,16 @@ SMTP(8) SMTP(8)
session cache.
<b><a href="postconf.5.html#smtp_tls_session_cache_timeout">smtp_tls_session_cache_timeout</a> (3600s)</b>
The expiration time of Postfix SMTP client TLS session cache
The expiration time of Postfix SMTP client TLS session cache
information.
<b><a href="postconf.5.html#smtp_tls_verify_cert_match">smtp_tls_verify_cert_match</a> (hostname)</b>
How the Postfix SMTP client verifies the server certificate
How the Postfix SMTP client verifies the server certificate
peername for the "verify" TLS security level.
<b><a href="postconf.5.html#tls_daemon_random_bytes">tls_daemon_random_bytes</a> (32)</b>
The number of pseudo-random bytes that an <a href="smtp.8.html"><b>smtp</b>(8)</a> or <a href="smtpd.8.html"><b>smtpd</b>(8)</a>
process requests from the <a href="tlsmgr.8.html"><b>tlsmgr</b>(8)</a> server in order to seed its
The number of pseudo-random bytes that an <a href="smtp.8.html"><b>smtp</b>(8)</a> or <a href="smtpd.8.html"><b>smtpd</b>(8)</a>
process requests from the <a href="tlsmgr.8.html"><b>tlsmgr</b>(8)</a> server in order to seed its
internal pseudo random number generator (PRNG).
<b><a href="postconf.5.html#tls_high_cipherlist">tls_high_cipherlist</a> (see 'postconf -d' output)</b>
@ -606,7 +604,7 @@ SMTP(8) SMTP(8)
The OpenSSL cipherlist for "medium" or higher grade ciphers.
<b><a href="postconf.5.html#tls_null_cipherlist">tls_null_cipherlist</a> (eNULL:!aNULL)</b>
The OpenSSL cipherlist for "NULL" grade ciphers that provide
The OpenSSL cipherlist for "NULL" grade ciphers that provide
authentication without encryption.
Available in in Postfix version 2.3..3.7:
@ -621,45 +619,45 @@ SMTP(8) SMTP(8)
<b><a href="postconf.5.html#smtp_sasl_tls_verified_security_options">smtp_sasl_tls_verified_security_options</a> ($<a href="postconf.5.html#smtp_sasl_tls_security_options">smtp_sasl_tls_secu</a>-</b>
<b><a href="postconf.5.html#smtp_sasl_tls_security_options">rity_options</a>)</b>
The SASL authentication security options that the Postfix SMTP
client uses for TLS encrypted SMTP sessions with a verified
The SASL authentication security options that the Postfix SMTP
client uses for TLS encrypted SMTP sessions with a verified
server certificate.
Available in Postfix version 2.5 and later:
<b><a href="postconf.5.html#smtp_tls_fingerprint_cert_match">smtp_tls_fingerprint_cert_match</a> (empty)</b>
List of acceptable remote SMTP server certificate fingerprints
for the "fingerprint" TLS security level (<b><a href="postconf.5.html#smtp_tls_security_level">smtp_tls_secu</a>-</b>
List of acceptable remote SMTP server certificate fingerprints
for the "fingerprint" TLS security level (<b><a href="postconf.5.html#smtp_tls_security_level">smtp_tls_secu</a>-</b>
<b><a href="postconf.5.html#smtp_tls_security_level">rity_level</a></b> = fingerprint).
<b><a href="postconf.5.html#smtp_tls_fingerprint_digest">smtp_tls_fingerprint_digest</a> (see 'postconf -d' output)</b>
The message digest algorithm used to construct remote SMTP
The message digest algorithm used to construct remote SMTP
server certificate fingerprints.
Available in Postfix version 2.6 and later:
<b><a href="postconf.5.html#smtp_tls_protocols">smtp_tls_protocols</a> (see 'postconf -d' output)</b>
TLS protocols that the Postfix SMTP client will use with oppor-
TLS protocols that the Postfix SMTP client will use with oppor-
tunistic TLS encryption.
<b><a href="postconf.5.html#smtp_tls_ciphers">smtp_tls_ciphers</a> (medium)</b>
The minimum TLS cipher grade that the Postfix SMTP client will
The minimum TLS cipher grade that the Postfix SMTP client will
use with opportunistic TLS encryption.
<b><a href="postconf.5.html#smtp_tls_eccert_file">smtp_tls_eccert_file</a> (empty)</b>
File with the Postfix SMTP client ECDSA certificate in PEM for-
File with the Postfix SMTP client ECDSA certificate in PEM for-
mat.
<b><a href="postconf.5.html#smtp_tls_eckey_file">smtp_tls_eckey_file</a> ($<a href="postconf.5.html#smtp_tls_eccert_file">smtp_tls_eccert_file</a>)</b>
File with the Postfix SMTP client ECDSA private key in PEM for-
File with the Postfix SMTP client ECDSA private key in PEM for-
mat.
Available in Postfix version 2.7 and later:
<b><a href="postconf.5.html#smtp_tls_block_early_mail_reply">smtp_tls_block_early_mail_reply</a> (no)</b>
Try to detect a mail hijacking attack based on a TLS protocol
vulnerability (CVE-2009-3555), where an attacker prepends mali-
cious HELO, MAIL, RCPT, DATA commands to a Postfix SMTP client
Try to detect a mail hijacking attack based on a TLS protocol
vulnerability (CVE-2009-3555), where an attacker prepends mali-
cious HELO, MAIL, RCPT, DATA commands to a Postfix SMTP client
TLS session.
Available in Postfix version 2.8 and later:
@ -679,11 +677,11 @@ SMTP(8) SMTP(8)
Available in Postfix version 2.11 and later:
<b><a href="postconf.5.html#smtp_tls_trust_anchor_file">smtp_tls_trust_anchor_file</a> (empty)</b>
Zero or more PEM-format files with trust-anchor certificates
Zero or more PEM-format files with trust-anchor certificates
and/or public keys.
<b><a href="postconf.5.html#smtp_tls_force_insecure_host_tlsa_lookup">smtp_tls_force_insecure_host_tlsa_lookup</a> (no)</b>
Lookup the associated DANE TLSA RRset even when a hostname is
Lookup the associated DANE TLSA RRset even when a hostname is
not an alias and its address records lie in an unsigned zone.
<b><a href="postconf.5.html#tlsmgr_service_name">tlsmgr_service_name</a> (tlsmgr)</b>
@ -692,20 +690,20 @@ SMTP(8) SMTP(8)
Available in Postfix version 3.0 and later:
<b><a href="postconf.5.html#smtp_tls_wrappermode">smtp_tls_wrappermode</a> (no)</b>
Request that the Postfix SMTP client connects using the SUBMIS-
Request that the Postfix SMTP client connects using the SUBMIS-
SIONS/SMTPS protocol instead of using the STARTTLS command.
Available in Postfix version 3.1 and later:
<b><a href="postconf.5.html#smtp_tls_dane_insecure_mx_policy">smtp_tls_dane_insecure_mx_policy</a> (see 'postconf -d' output)</b>
The TLS policy for MX hosts with "secure" TLSA records when the
nexthop destination security level is <b>dane</b>, but the MX record
The TLS policy for MX hosts with "secure" TLSA records when the
nexthop destination security level is <b>dane</b>, but the MX record
was found via an "insecure" MX lookup.
Available in Postfix version 3.2 and later:
<b><a href="postconf.5.html#tls_eecdh_auto_curves">tls_eecdh_auto_curves</a> (see 'postconf -d' output)</b>
The prioritized list of elliptic curves, that should be enabled
The prioritized list of elliptic curves, that should be enabled
in the Postfix SMTP client and server.
Available in Postfix version 3.4 and later:
@ -714,23 +712,23 @@ SMTP(8) SMTP(8)
Try to make multiple deliveries per TLS-encrypted connection.
<b><a href="postconf.5.html#smtp_tls_chain_files">smtp_tls_chain_files</a> (empty)</b>
List of one or more PEM files, each holding one or more private
List of one or more PEM files, each holding one or more private
keys directly followed by a corresponding certificate chain.
<b><a href="postconf.5.html#smtp_tls_servername">smtp_tls_servername</a> (empty)</b>
Optional name to send to the remote SMTP server in the TLS
Optional name to send to the remote SMTP server in the TLS
Server Name Indication (SNI) extension.
Available in Postfix 3.5, 3.4.6, 3.3.5, 3.2.10, 3.1.13 and later:
<b><a href="postconf.5.html#tls_fast_shutdown_enable">tls_fast_shutdown_enable</a> (yes)</b>
A workaround for implementations that hang Postfix while shut-
A workaround for implementations that hang Postfix while shut-
ting down a TLS session, until Postfix times out.
Available in Postfix version 3.8 and later:
<b><a href="postconf.5.html#tls_ffdhe_auto_groups">tls_ffdhe_auto_groups</a> (see 'postconf -d' output)</b>
The prioritized list of finite-field Diffie-Hellman ephemeral
The prioritized list of finite-field Diffie-Hellman ephemeral
(FFDHE) key exchange groups supported by the Postfix SMTP client
and server.
@ -740,15 +738,17 @@ SMTP(8) SMTP(8)
Optional configuration file with baseline OpenSSL settings.
<b><a href="postconf.5.html#tls_config_name">tls_config_name</a> (empty)</b>
The application name passed by Postfix to OpenSSL library ini-
The application name passed by Postfix to OpenSSL library ini-
tialization functions.
Available in Postfix version 3.9 and later:
<b><a href="postconf.5.html#smtp_tls_enable_rpk">smtp_tls_enable_rpk</a> (no)</b>
Request that remote SMTP servers send an <a href="https://tools.ietf.org/html/rfc7250">RFC7250</a> raw public key
Request that remote SMTP servers send an <a href="https://tools.ietf.org/html/rfc7250">RFC7250</a> raw public key
instead of an X.509 certificate.
Available in Postfix version 3.10 and later:
<b><a href="postconf.5.html#smtp_tlsrpt_enable">smtp_tlsrpt_enable</a> (no)</b>
Enable support for <a href="https://tools.ietf.org/html/rfc8460">RFC 8460</a> TLSRPT notifications.
@ -758,48 +758,48 @@ SMTP(8) SMTP(8)
<b><a href="postconf.5.html#smtp_tlsrpt_skip_reused_handshakes">smtp_tlsrpt_skip_reused_handshakes</a> (yes)</b>
Do not report the TLSRPT status for TLS protocol handshakes that
reuse a previously-negotiated TLS session (there is no new
reuse a previously-negotiated TLS session (there is no new
information to report).
<b><a href="postconf.5.html#requiretls_enable">requiretls_enable</a> (yes)</b>
Enable support for the ESMTP verb "REQUIRETLS", defined in <a href="https://tools.ietf.org/html/rfc8689">RFC</a>
Enable support for the ESMTP verb "REQUIRETLS", defined in <a href="https://tools.ietf.org/html/rfc8689">RFC</a>
<a href="https://tools.ietf.org/html/rfc8689">8689</a>.
<b><a name="obsolete_tls_controls">OBSOLETE TLS CONTROLS</a></b>
The following configuration parameters exist for compatibility with
Postfix versions before 2.3. Support for these will be removed in a
The following configuration parameters exist for compatibility with
Postfix versions before 2.3. Support for these will be removed in a
future release.
<b><a href="postconf.5.html#smtp_use_tls">smtp_use_tls</a> (no)</b>
Opportunistic mode: use TLS when a remote SMTP server announces
Opportunistic mode: use TLS when a remote SMTP server announces
STARTTLS support, otherwise send the mail in the clear.
<b><a href="postconf.5.html#smtp_enforce_tls">smtp_enforce_tls</a> (no)</b>
Enforcement mode: require that remote SMTP servers use TLS
Enforcement mode: require that remote SMTP servers use TLS
encryption, and never send mail in the clear.
<b><a href="postconf.5.html#smtp_tls_enforce_peername">smtp_tls_enforce_peername</a> (yes)</b>
With mandatory TLS encryption, require that the remote SMTP
server hostname matches the information in the remote SMTP
With mandatory TLS encryption, require that the remote SMTP
server hostname matches the information in the remote SMTP
server certificate.
<b><a href="postconf.5.html#smtp_tls_per_site">smtp_tls_per_site</a> (empty)</b>
Optional lookup tables with the Postfix SMTP client TLS usage
policy by next-hop destination and by remote SMTP server host-
Optional lookup tables with the Postfix SMTP client TLS usage
policy by next-hop destination and by remote SMTP server host-
name.
<b><a href="postconf.5.html#smtp_tls_cipherlist">smtp_tls_cipherlist</a> (empty)</b>
Obsolete Postfix &lt; 2.3 control for the Postfix SMTP client TLS
Obsolete Postfix &lt; 2.3 control for the Postfix SMTP client TLS
cipher list.
<b><a name="resource_and_rate_controls">RESOURCE AND RATE CONTROLS</a></b>
<b><a href="postconf.5.html#smtp_connect_timeout">smtp_connect_timeout</a> (30s)</b>
The Postfix SMTP client time limit for completing a TCP connec-
The Postfix SMTP client time limit for completing a TCP connec-
tion, or zero (use the operating system built-in time limit).
<b><a href="postconf.5.html#smtp_helo_timeout">smtp_helo_timeout</a> (300s)</b>
The Postfix SMTP client time limit for sending the HELO or EHLO
command, and for receiving the initial remote SMTP server
The Postfix SMTP client time limit for sending the HELO or EHLO
command, and for receiving the initial remote SMTP server
response.
<b><a href="postconf.5.html#lmtp_lhlo_timeout">lmtp_lhlo_timeout</a> (300s)</b>
@ -811,19 +811,19 @@ SMTP(8) SMTP(8)
mand, and for receiving the remote SMTP server response.
<b><a href="postconf.5.html#smtp_mail_timeout">smtp_mail_timeout</a> (300s)</b>
The Postfix SMTP client time limit for sending the MAIL FROM
The Postfix SMTP client time limit for sending the MAIL FROM
command, and for receiving the remote SMTP server response.
<b><a href="postconf.5.html#smtp_rcpt_timeout">smtp_rcpt_timeout</a> (300s)</b>
The Postfix SMTP client time limit for sending the SMTP RCPT TO
The Postfix SMTP client time limit for sending the SMTP RCPT TO
command, and for receiving the remote SMTP server response.
<b><a href="postconf.5.html#smtp_data_init_timeout">smtp_data_init_timeout</a> (120s)</b>
The Postfix SMTP client time limit for sending the SMTP DATA
The Postfix SMTP client time limit for sending the SMTP DATA
command, and for receiving the remote SMTP server response.
<b><a href="postconf.5.html#smtp_data_xfer_timeout">smtp_data_xfer_timeout</a> (180s)</b>
The Postfix SMTP client time limit for sending the SMTP message
The Postfix SMTP client time limit for sending the SMTP message
content.
<b><a href="postconf.5.html#smtp_data_done_timeout">smtp_data_done_timeout</a> (600s)</b>
@ -837,13 +837,13 @@ SMTP(8) SMTP(8)
Available in Postfix version 2.1 and later:
<b><a href="postconf.5.html#smtp_mx_address_limit">smtp_mx_address_limit</a> (5)</b>
The maximal number of MX (mail exchanger) IP addresses that can
result from Postfix SMTP client mail exchanger lookups, or zero
The maximal number of MX (mail exchanger) IP addresses that can
result from Postfix SMTP client mail exchanger lookups, or zero
(no limit).
<b><a href="postconf.5.html#smtp_mx_session_limit">smtp_mx_session_limit</a> (2)</b>
The maximal number of SMTP sessions per delivery request before
the Postfix SMTP client gives up or delivers to a fall-back
The maximal number of SMTP sessions per delivery request before
the Postfix SMTP client gives up or delivers to a fall-back
<a href="postconf.5.html#relayhost">relay host</a>, or zero (no limit).
<b><a href="postconf.5.html#smtp_rset_timeout">smtp_rset_timeout</a> (20s)</b>
@ -853,17 +853,17 @@ SMTP(8) SMTP(8)
Available in Postfix version 2.2 and earlier:
<b><a href="postconf.5.html#lmtp_cache_connection">lmtp_cache_connection</a> (yes)</b>
Keep Postfix LMTP client connections open for up to $<a href="postconf.5.html#max_idle">max_idle</a>
Keep Postfix LMTP client connections open for up to $<a href="postconf.5.html#max_idle">max_idle</a>
seconds.
Available in Postfix version 2.2 and later:
<b><a href="postconf.5.html#smtp_connection_cache_destinations">smtp_connection_cache_destinations</a> (empty)</b>
Permanently enable SMTP connection caching for the specified
Permanently enable SMTP connection caching for the specified
destinations.
<b><a href="postconf.5.html#smtp_connection_cache_on_demand">smtp_connection_cache_on_demand</a> (yes)</b>
Temporarily enable SMTP connection caching while a destination
Temporarily enable SMTP connection caching while a destination
has a high volume of mail in the <a href="QSHAPE_README.html#active_queue">active queue</a>.
<b><a href="postconf.5.html#smtp_connection_reuse_time_limit">smtp_connection_reuse_time_limit</a> (300s)</b>
@ -877,23 +877,23 @@ SMTP(8) SMTP(8)
Available in Postfix version 2.3 and later:
<b><a href="postconf.5.html#connection_cache_protocol_timeout">connection_cache_protocol_timeout</a> (5s)</b>
Time limit for connection cache connect, send or receive opera-
Time limit for connection cache connect, send or receive opera-
tions.
Available in Postfix version 2.9 - 3.6:
<b><a href="postconf.5.html#smtp_per_record_deadline">smtp_per_record_deadline</a> (no)</b>
Change the behavior of the smtp_*_timeout time limits, from a
time limit per read or write system call, to a time limit to
send or receive a complete record (an SMTP command line, SMTP
response line, SMTP message content line, or TLS protocol mes-
Change the behavior of the smtp_*_timeout time limits, from a
time limit per read or write system call, to a time limit to
send or receive a complete record (an SMTP command line, SMTP
response line, SMTP message content line, or TLS protocol mes-
sage).
Available in Postfix version 2.11 and later:
<b><a href="postconf.5.html#smtp_connection_reuse_count_limit">smtp_connection_reuse_count_limit</a> (0)</b>
When SMTP connection caching is enabled, the number of times
that an SMTP session may be reused before it is closed, or zero
When SMTP connection caching is enabled, the number of times
that an SMTP session may be reused before it is closed, or zero
(no limit).
Available in Postfix version 3.4 and later:
@ -904,13 +904,13 @@ SMTP(8) SMTP(8)
Available in Postfix version 3.7 and later:
<b><a href="postconf.5.html#smtp_per_request_deadline">smtp_per_request_deadline</a> (no)</b>
Change the behavior of the smtp_*_timeout time limits, from a
time limit per plaintext or TLS read or write call, to a com-
bined time limit for sending a complete SMTP request and for
Change the behavior of the smtp_*_timeout time limits, from a
time limit per plaintext or TLS read or write call, to a com-
bined time limit for sending a complete SMTP request and for
receiving a complete SMTP response.
<b><a href="postconf.5.html#smtp_min_data_rate">smtp_min_data_rate</a> (500)</b>
The minimum plaintext data transfer rate in bytes/second for
The minimum plaintext data transfer rate in bytes/second for
DATA requests, when deadlines are enabled with
<a href="postconf.5.html#smtp_per_request_deadline">smtp_per_request_deadline</a>.
@ -918,54 +918,54 @@ SMTP(8) SMTP(8)
<b><a href="postconf.5.html#transport_destination_concurrency_limit">transport_destination_concurrency_limit</a> ($<a href="postconf.5.html#default_destination_concurrency_limit">default_destination_concur</a>-</b>
<b><a href="postconf.5.html#default_destination_concurrency_limit">rency_limit</a>)</b>
A transport-specific override for the <a href="postconf.5.html#default_destination_concurrency_limit">default_destination_con</a>-
A transport-specific override for the <a href="postconf.5.html#default_destination_concurrency_limit">default_destination_con</a>-
<a href="postconf.5.html#default_destination_concurrency_limit">currency_limit</a> parameter value, where <i>transport</i> is the <a href="master.5.html">master.cf</a>
name of the message delivery transport.
<b><a href="postconf.5.html#transport_destination_recipient_limit">transport_destination_recipient_limit</a> ($<a href="postconf.5.html#default_destination_recipient_limit">default_destination_recipi</a>-</b>
<b><a href="postconf.5.html#default_destination_recipient_limit">ent_limit</a>)</b>
A transport-specific override for the <a href="postconf.5.html#default_destination_recipient_limit">default_destination_recip</a>-
<a href="postconf.5.html#default_destination_recipient_limit">ient_limit</a> parameter value, where <i>transport</i> is the <a href="master.5.html">master.cf</a>
<a href="postconf.5.html#default_destination_recipient_limit">ient_limit</a> parameter value, where <i>transport</i> is the <a href="master.5.html">master.cf</a>
name of the message delivery transport.
<b><a name="smtputf8_controls">SMTPUTF8 CONTROLS</a></b>
Preliminary SMTPUTF8 support is introduced with Postfix 3.0.
<b><a href="postconf.5.html#smtputf8_enable">smtputf8_enable</a> (yes)</b>
Enable preliminary SMTPUTF8 support for the protocols described
Enable preliminary SMTPUTF8 support for the protocols described
in <a href="https://tools.ietf.org/html/rfc6531">RFC 6531</a>, <a href="https://tools.ietf.org/html/rfc6532">RFC 6532</a>, and <a href="https://tools.ietf.org/html/rfc6533">RFC 6533</a>.
<b><a href="postconf.5.html#smtputf8_autodetect_classes">smtputf8_autodetect_classes</a> (sendmail, verify)</b>
Detect that a message requires SMTPUTF8 support for the speci-
Detect that a message requires SMTPUTF8 support for the speci-
fied mail origin classes.
Available in Postfix version 3.2 and later:
<b><a href="postconf.5.html#enable_idna2003_compatibility">enable_idna2003_compatibility</a> (no)</b>
Enable 'transitional' compatibility between IDNA2003 and
IDNA2008, when converting UTF-8 domain names to/from the ASCII
Enable 'transitional' compatibility between IDNA2003 and
IDNA2008, when converting UTF-8 domain names to/from the ASCII
form that is used for DNS lookups.
<b><a name="trouble_shooting_controls">TROUBLE SHOOTING CONTROLS</a></b>
<b><a href="postconf.5.html#debug_peer_level">debug_peer_level</a> (2)</b>
The increment in verbose logging level when a nexthop destina-
tion, remote client or server name or network address matches a
The increment in verbose logging level when a nexthop destina-
tion, remote client or server name or network address matches a
pattern given with the <a href="postconf.5.html#debug_peer_list">debug_peer_list</a> parameter.
<b><a href="postconf.5.html#debug_peer_list">debug_peer_list</a> (empty)</b>
Optional list of nexthop destination, remote client or server
name or network address patterns that, if matched, cause the
verbose logging level to increase by the amount specified in
Optional list of nexthop destination, remote client or server
name or network address patterns that, if matched, cause the
verbose logging level to increase by the amount specified in
$<a href="postconf.5.html#debug_peer_level">debug_peer_level</a>.
<b><a href="postconf.5.html#error_notice_recipient">error_notice_recipient</a> (postmaster)</b>
The recipient of postmaster notifications about mail delivery
The recipient of postmaster notifications about mail delivery
problems that are caused by policy, resource, software or proto-
col errors.
<b><a href="postconf.5.html#internal_mail_filter_classes">internal_mail_filter_classes</a> (empty)</b>
What categories of Postfix-generated mail are subject to
before-queue content inspection by <a href="postconf.5.html#non_smtpd_milters">non_smtpd_milters</a>,
What categories of Postfix-generated mail are subject to
before-queue content inspection by <a href="postconf.5.html#non_smtpd_milters">non_smtpd_milters</a>,
<a href="postconf.5.html#header_checks">header_checks</a> and <a href="postconf.5.html#body_checks">body_checks</a>.
<b><a href="postconf.5.html#notify_classes">notify_classes</a> (resource, software)</b>
@ -973,46 +973,46 @@ SMTP(8) SMTP(8)
<b><a name="miscellaneous_controls">MISCELLANEOUS CONTROLS</a></b>
<b><a href="postconf.5.html#best_mx_transport">best_mx_transport</a> (empty)</b>
Where the Postfix SMTP client should deliver mail when it
Where the Postfix SMTP client should deliver mail when it
detects a "mail loops back to myself" error condition.
<b><a href="postconf.5.html#config_directory">config_directory</a> (see 'postconf -d' output)</b>
The default location of the Postfix <a href="postconf.5.html">main.cf</a> and <a href="master.5.html">master.cf</a> con-
The default location of the Postfix <a href="postconf.5.html">main.cf</a> and <a href="master.5.html">master.cf</a> con-
figuration files.
<b><a href="postconf.5.html#daemon_timeout">daemon_timeout</a> (18000s)</b>
How much time a Postfix daemon process may take to handle a
How much time a Postfix daemon process may take to handle a
request before it is terminated by a built-in watchdog timer.
<b><a href="postconf.5.html#delay_logging_resolution_limit">delay_logging_resolution_limit</a> (2)</b>
The maximal number of digits after the decimal point when log-
The maximal number of digits after the decimal point when log-
ging delay values.
<b><a href="postconf.5.html#disable_dns_lookups">disable_dns_lookups</a> (no)</b>
Disable DNS lookups in the Postfix SMTP and LMTP clients.
<b><a href="postconf.5.html#inet_interfaces">inet_interfaces</a> (all)</b>
The local network interface addresses that this mail system
The local network interface addresses that this mail system
receives mail on.
<b><a href="postconf.5.html#inet_protocols">inet_protocols</a> (see 'postconf -d' output)</b>
The Internet protocols Postfix will attempt to use when making
The Internet protocols Postfix will attempt to use when making
or accepting connections.
<b><a href="postconf.5.html#ipc_timeout">ipc_timeout</a> (3600s)</b>
The time limit for sending or receiving information over an
The time limit for sending or receiving information over an
internal communication channel.
<b><a href="postconf.5.html#lmtp_assume_final">lmtp_assume_final</a> (no)</b>
When a remote LMTP server announces no DSN support, assume that
the server performs final delivery, and send "delivered" deliv-
When a remote LMTP server announces no DSN support, assume that
the server performs final delivery, and send "delivered" deliv-
ery status notifications instead of "relayed".
<b><a href="postconf.5.html#lmtp_tcp_port">lmtp_tcp_port</a> (24)</b>
The default TCP port that the Postfix LMTP client connects to.
<b><a href="postconf.5.html#max_idle">max_idle</a> (100s)</b>
The maximum amount of time that an idle Postfix daemon process
The maximum amount of time that an idle Postfix daemon process
waits for an incoming connection before terminating voluntarily.
<b><a href="postconf.5.html#max_use">max_use</a> (100)</b>
@ -1026,21 +1026,21 @@ SMTP(8) SMTP(8)
The process name of a Postfix command or daemon process.
<b><a href="postconf.5.html#proxy_interfaces">proxy_interfaces</a> (empty)</b>
The remote network interface addresses that this mail system
receives mail on by way of a proxy or network address transla-
The remote network interface addresses that this mail system
receives mail on by way of a proxy or network address transla-
tion unit.
<b><a href="postconf.5.html#smtp_address_preference">smtp_address_preference</a> (any)</b>
The address type ("ipv6", "ipv4" or "any") that the Postfix SMTP
client will try first, when a destination has IPv6 and IPv4
client will try first, when a destination has IPv6 and IPv4
addresses with equal MX preference.
<b><a href="postconf.5.html#smtp_bind_address">smtp_bind_address</a> (empty)</b>
An optional numerical network address that the Postfix SMTP
An optional numerical network address that the Postfix SMTP
client should bind to when making an IPv4 connection.
<b><a href="postconf.5.html#smtp_bind_address6">smtp_bind_address6</a> (empty)</b>
An optional numerical network address that the Postfix SMTP
An optional numerical network address that the Postfix SMTP
client should bind to when making an IPv6 connection.
<b><a href="postconf.5.html#smtp_helo_name">smtp_helo_name</a> ($<a href="postconf.5.html#myhostname">myhostname</a>)</b>
@ -1060,7 +1060,7 @@ SMTP(8) SMTP(8)
The syslog facility of Postfix logging.
<b><a href="postconf.5.html#syslog_name">syslog_name</a> (see 'postconf -d' output)</b>
A prefix that is prepended to the process name in syslog
A prefix that is prepended to the process name in syslog
records, so that, for example, "smtpd" becomes "prefix/smtpd".
Available with Postfix 2.2 and earlier:
@ -1072,14 +1072,14 @@ SMTP(8) SMTP(8)
Available with Postfix 2.3 and later:
<b><a href="postconf.5.html#smtp_fallback_relay">smtp_fallback_relay</a> ($<a href="postconf.5.html#fallback_relay">fallback_relay</a>)</b>
Optional list of relay destinations that will be used when an
SMTP destination is not found, or when delivery fails due to a
Optional list of relay destinations that will be used when an
SMTP destination is not found, or when delivery fails due to a
non-permanent error.
Available with Postfix 3.0 and later:
<b><a href="postconf.5.html#smtp_address_verify_target">smtp_address_verify_target</a> (rcpt)</b>
In the context of email address verification, the SMTP protocol
In the context of email address verification, the SMTP protocol
stage that determines whether an email address is deliverable.
Available with Postfix 3.1 and later:
@ -1101,7 +1101,7 @@ SMTP(8) SMTP(8)
Available in Postfix 3.7 and later:
<b><a href="postconf.5.html#smtp_bind_address_enforce">smtp_bind_address_enforce</a> (no)</b>
Defer delivery when the Postfix SMTP client cannot apply the
Defer delivery when the Postfix SMTP client cannot apply the
<a href="postconf.5.html#smtp_bind_address">smtp_bind_address</a> or <a href="postconf.5.html#smtp_bind_address6">smtp_bind_address6</a> setting.
<b><a name="see_also">SEE ALSO</a></b>

16
postfix/html/postconf.5.html
View File

@ -10575,13 +10575,15 @@ the mail server (IMPORTING HOME DIRECTORIES IS NOT RECOMMENDED).
<p> Enable support for the ESMTP verb "REQUIRETLS", defined in <a href="https://tools.ietf.org/html/rfc8689">RFC</a>
<a href="https://tools.ietf.org/html/rfc8689">8689</a>. By issuing this verb in the "MAIL FROM" command, a sender
requires that a message must be delivered over TLS connections with
a verified server certificate. This corresponds to the Postfix SMTP
client TLS security levels "secure", "verify", "fingerprint",
opportunistic "dane" with a successful certificate match, or
"dane-only" (the postfix-mta-sts-resolver plugin tells Postfix to
enforce a "secure with certificate match" policy). Otherwise, Postfix
returns the message as undeliverable. </p>
specifies that a message must be delivered over TLS connections
with a verified server certificate, to a server that announces
"REQUIRETLS" support. This corresponds to the Postfix SMTP client
TLS security levels "secure", "verify", "fingerprint", dane-only,
or opportunistic "dane", with a successful certificate match. The
Postfix SMTP client will try one or more servers, controlled with
the <a href="postconf.5.html#smtp_mx_address_limit">smtp_mx_address_limit</a> parameter, until it finds a server that
satisfies requirements. Otherwise, Postfix returns the message as
undeliverable. </p>
<p> Note: REQUIRETLS overrides "TLS-Required: no". </p>

372
postfix/html/smtp.8.html
View File

@ -143,11 +143,9 @@ SMTP(8) SMTP(8)
<b>X</b> Indicates that the delivery is final. This flag affects
the status reported in "success" DSN (delivery status
notification) messages, and changes it from "relayed"
into "delivered". The flag also suppresses the require-
ment that the remote server announces REQUIRETLS support.
into "delivered".
This feature is available as of Postfix 3.5; REQUIRETLS
support was introduced with Postfix 3.10.
This feature is available as of Postfix 3.5.
<b><a name="security">SECURITY</a></b>
The SMTP+LMTP client is moderately security-sensitive. It talks to SMTP
@ -179,34 +177,34 @@ SMTP(8) SMTP(8)
<a href="https://tools.ietf.org/html/rfc8689">RFC 8689</a> (SMTP REQUIRETLS extension)
<b><a name="diagnostics">DIAGNOSTICS</a></b>
Problems and transactions are logged to <b>syslogd</b>(8) or <a href="postlogd.8.html"><b>postlogd</b>(8)</a>.
Corrupted message files are marked so that the queue manager can move
Problems and transactions are logged to <b>syslogd</b>(8) or <a href="postlogd.8.html"><b>postlogd</b>(8)</a>.
Corrupted message files are marked so that the queue manager can move
them to the <b>corrupt</b> queue for further inspection.
Depending on the setting of the <b><a href="postconf.5.html#notify_classes">notify_classes</a></b> parameter, the postmas-
Depending on the setting of the <b><a href="postconf.5.html#notify_classes">notify_classes</a></b> parameter, the postmas-
ter is notified of bounces, protocol problems, and of other trouble.
<b><a name="bugs">BUGS</a></b>
SMTP and LMTP connection reuse for TLS (without closing the SMTP or
SMTP and LMTP connection reuse for TLS (without closing the SMTP or
LMTP connection) is not supported before Postfix 3.4.
SMTP and LMTP connection reuse assumes that SASL credentials are valid
SMTP and LMTP connection reuse assumes that SASL credentials are valid
for all destinations that map onto the same IP address and TCP port.
<b><a name="configuration_parameters">CONFIGURATION PARAMETERS</a></b>
Postfix versions 2.3 and later implement the SMTP and LMTP client with
the same program, and choose the protocol and configuration parameters
Postfix versions 2.3 and later implement the SMTP and LMTP client with
the same program, and choose the protocol and configuration parameters
based on the process name, <b>smtp</b> or <b>lmtp</b>.
Most smtp_<i>xxx</i> configuration parameters have an lmtp_<i>xxx</i> "mirror" param-
eter for the equivalent LMTP feature. This document describes only
eter for the equivalent LMTP feature. This document describes only
those LMTP-related parameters that aren't simply "mirror" parameters.
Changes to <a href="postconf.5.html"><b>main.cf</b></a> are picked up automatically, as <a href="smtp.8.html"><b>smtp</b>(8)</a> processes
Changes to <a href="postconf.5.html"><b>main.cf</b></a> are picked up automatically, as <a href="smtp.8.html"><b>smtp</b>(8)</a> processes
run for only a limited amount of time. Use the command "<b>postfix reload</b>"
to speed up a change.
The text below provides only a parameter summary. See <a href="postconf.5.html"><b>postconf</b>(5)</a> for
The text below provides only a parameter summary. See <a href="postconf.5.html"><b>postconf</b>(5)</a> for
more details including examples.
<b><a name="compatibility_controls">COMPATIBILITY CONTROLS</a></b>
@ -227,8 +225,8 @@ SMTP(8) SMTP(8)
will send via SMTP.
<b><a href="postconf.5.html#smtp_pix_workaround_delay_time">smtp_pix_workaround_delay_time</a> (10s)</b>
How long the Postfix SMTP client pauses before sending
".&lt;CR&gt;&lt;LF&gt;" in order to work around the PIX firewall
How long the Postfix SMTP client pauses before sending
".&lt;CR&gt;&lt;LF&gt;" in order to work around the PIX firewall
"&lt;CR&gt;&lt;LF&gt;.&lt;CR&gt;&lt;LF&gt;" bug.
<b><a href="postconf.5.html#smtp_pix_workaround_threshold_time">smtp_pix_workaround_threshold_time</a> (500s)</b>
@ -237,19 +235,19 @@ SMTP(8) SMTP(8)
delivery through firewalls with "smtp fixup" mode turned on.
<b><a href="postconf.5.html#smtp_pix_workarounds">smtp_pix_workarounds</a> (disable_esmtp, delay_dotcrlf)</b>
A list that specifies zero or more workarounds for CISCO PIX
A list that specifies zero or more workarounds for CISCO PIX
firewall bugs.
<b><a href="postconf.5.html#smtp_pix_workaround_maps">smtp_pix_workaround_maps</a> (empty)</b>
Lookup tables, indexed by the remote SMTP server address, with
Lookup tables, indexed by the remote SMTP server address, with
per-destination workarounds for CISCO PIX firewall bugs.
<b><a href="postconf.5.html#smtp_quote_rfc821_envelope">smtp_quote_rfc821_envelope</a> (yes)</b>
Quote addresses in Postfix SMTP client MAIL FROM and RCPT TO
Quote addresses in Postfix SMTP client MAIL FROM and RCPT TO
commands as required by <a href="https://tools.ietf.org/html/rfc5321">RFC 5321</a>.
<b><a href="postconf.5.html#smtp_reply_filter">smtp_reply_filter</a> (empty)</b>
A mechanism to transform replies from remote SMTP servers one
A mechanism to transform replies from remote SMTP servers one
line at a time.
<b><a href="postconf.5.html#smtp_skip_5xx_greeting">smtp_skip_5xx_greeting</a> (yes)</b>
@ -261,68 +259,68 @@ SMTP(8) SMTP(8)
Available in Postfix version 2.0 and earlier:
<b><a href="postconf.5.html#smtp_skip_4xx_greeting">smtp_skip_4xx_greeting</a> (yes)</b>
Skip SMTP servers that greet with a 4XX status code (go away,
Skip SMTP servers that greet with a 4XX status code (go away,
try again later).
Available in Postfix version 2.2 and later:
<b><a href="postconf.5.html#smtp_discard_ehlo_keyword_address_maps">smtp_discard_ehlo_keyword_address_maps</a> (empty)</b>
Lookup tables, indexed by the remote SMTP server address, with
case insensitive lists of EHLO keywords (pipelining, starttls,
Lookup tables, indexed by the remote SMTP server address, with
case insensitive lists of EHLO keywords (pipelining, starttls,
auth, etc.) that the Postfix SMTP client will ignore in the EHLO
response from a remote SMTP server.
<b><a href="postconf.5.html#smtp_discard_ehlo_keywords">smtp_discard_ehlo_keywords</a> (empty)</b>
A case insensitive list of EHLO keywords (pipelining, starttls,
A case insensitive list of EHLO keywords (pipelining, starttls,
auth, etc.) that the Postfix SMTP client will ignore in the EHLO
response from a remote SMTP server.
<b><a href="postconf.5.html#smtp_generic_maps">smtp_generic_maps</a> (empty)</b>
Optional lookup tables that perform address rewriting in the
Postfix SMTP client, typically to transform a locally valid
address into a globally valid address when sending mail across
Optional lookup tables that perform address rewriting in the
Postfix SMTP client, typically to transform a locally valid
address into a globally valid address when sending mail across
the Internet.
Available in Postfix version 2.2.9 and later:
<b><a href="postconf.5.html#smtp_cname_overrides_servername">smtp_cname_overrides_servername</a> (version dependent)</b>
When the remote SMTP servername is a DNS CNAME, replace the
servername with the result from CNAME expansion for the purpose
of logging, SASL password lookup, TLS policy decisions, or TLS
When the remote SMTP servername is a DNS CNAME, replace the
servername with the result from CNAME expansion for the purpose
of logging, SASL password lookup, TLS policy decisions, or TLS
certificate verification.
Available in Postfix version 2.3 and later:
<b><a href="postconf.5.html#lmtp_discard_lhlo_keyword_address_maps">lmtp_discard_lhlo_keyword_address_maps</a> (empty)</b>
Lookup tables, indexed by the remote LMTP server address, with
case insensitive lists of LHLO keywords (pipelining, starttls,
Lookup tables, indexed by the remote LMTP server address, with
case insensitive lists of LHLO keywords (pipelining, starttls,
auth, etc.) that the Postfix LMTP client will ignore in the LHLO
response from a remote LMTP server.
<b><a href="postconf.5.html#lmtp_discard_lhlo_keywords">lmtp_discard_lhlo_keywords</a> (empty)</b>
A case insensitive list of LHLO keywords (pipelining, starttls,
A case insensitive list of LHLO keywords (pipelining, starttls,
auth, etc.) that the Postfix LMTP client will ignore in the LHLO
response from a remote LMTP server.
Available in Postfix version 2.4.4 and later:
<b><a href="postconf.5.html#send_cyrus_sasl_authzid">send_cyrus_sasl_authzid</a> (no)</b>
When authenticating to a remote SMTP or LMTP server with the
default setting "no", send no SASL authoriZation ID (authzid);
send only the SASL authentiCation ID (authcid) plus the auth-
When authenticating to a remote SMTP or LMTP server with the
default setting "no", send no SASL authoriZation ID (authzid);
send only the SASL authentiCation ID (authcid) plus the auth-
cid's password.
Available in Postfix version 2.5 and later:
<b><a href="postconf.5.html#smtp_header_checks">smtp_header_checks</a> (empty)</b>
Restricted <a href="header_checks.5.html"><b>header_checks</b>(5)</a> tables for the Postfix SMTP client.
Restricted <a href="header_checks.5.html"><b>header_checks</b>(5)</a> tables for the Postfix SMTP client.
<b><a href="postconf.5.html#smtp_mime_header_checks">smtp_mime_header_checks</a> (empty)</b>
Restricted <b><a href="postconf.5.html#mime_header_checks">mime_header_checks</a></b>(5) tables for the Postfix SMTP
Restricted <b><a href="postconf.5.html#mime_header_checks">mime_header_checks</a></b>(5) tables for the Postfix SMTP
client.
<b><a href="postconf.5.html#smtp_nested_header_checks">smtp_nested_header_checks</a> (empty)</b>
Restricted <b><a href="postconf.5.html#nested_header_checks">nested_header_checks</a></b>(5) tables for the Postfix SMTP
Restricted <b><a href="postconf.5.html#nested_header_checks">nested_header_checks</a></b>(5) tables for the Postfix SMTP
client.
<b><a href="postconf.5.html#smtp_body_checks">smtp_body_checks</a> (empty)</b>
@ -331,7 +329,7 @@ SMTP(8) SMTP(8)
Available in Postfix version 2.6 and later:
<b><a href="postconf.5.html#tcp_windowsize">tcp_windowsize</a> (0)</b>
An optional workaround for routers that break TCP window scal-
An optional workaround for routers that break TCP window scal-
ing.
Available in Postfix version 2.8 and later:
@ -342,16 +340,16 @@ SMTP(8) SMTP(8)
Available in Postfix version 2.9 - 3.6:
<b><a href="postconf.5.html#smtp_per_record_deadline">smtp_per_record_deadline</a> (no)</b>
Change the behavior of the smtp_*_timeout time limits, from a
time limit per read or write system call, to a time limit to
send or receive a complete record (an SMTP command line, SMTP
response line, SMTP message content line, or TLS protocol mes-
Change the behavior of the smtp_*_timeout time limits, from a
time limit per read or write system call, to a time limit to
send or receive a complete record (an SMTP command line, SMTP
response line, SMTP message content line, or TLS protocol mes-
sage).
Available in Postfix version 2.9 and later:
<b><a href="postconf.5.html#smtp_send_dummy_mail_auth">smtp_send_dummy_mail_auth</a> (no)</b>
Whether or not to append the "AUTH=&lt;&gt;" option to the MAIL FROM
Whether or not to append the "AUTH=&lt;&gt;" option to the MAIL FROM
command in SASL-authenticated SMTP sessions.
Available in Postfix version 2.11 and later:
@ -362,7 +360,7 @@ SMTP(8) SMTP(8)
Available in Postfix version 3.0 and later:
<b><a href="postconf.5.html#smtp_delivery_status_filter">smtp_delivery_status_filter</a> ($<a href="postconf.5.html#default_delivery_status_filter">default_delivery_status_filter</a>)</b>
Optional filter for the <a href="smtp.8.html"><b>smtp</b>(8)</a> delivery agent to change the
Optional filter for the <a href="smtp.8.html"><b>smtp</b>(8)</a> delivery agent to change the
delivery status code or explanatory text of successful or unsuc-
cessful deliveries.
@ -372,38 +370,38 @@ SMTP(8) SMTP(8)
Available in Postfix version 3.3 and later:
<b><a href="postconf.5.html#smtp_balance_inet_protocols">smtp_balance_inet_protocols</a> (yes)</b>
When a remote destination resolves to a combination of IPv4 and
When a remote destination resolves to a combination of IPv4 and
IPv6 addresses, ensure that the Postfix SMTP client can try both
address types before it runs into the <a href="postconf.5.html#smtp_mx_address_limit">smtp_mx_address_limit</a>.
Available in Postfix 3.5 and later:
<b><a href="postconf.5.html#info_log_address_format">info_log_address_format</a> (external)</b>
The email address form that will be used in non-debug logging
The email address form that will be used in non-debug logging
(info, warning, etc.).
Available in Postfix 3.6 and later:
<b><a href="postconf.5.html#dnssec_probe">dnssec_probe</a> (ns:.)</b>
The DNS query type (default: "ns") and DNS query name (default:
The DNS query type (default: "ns") and DNS query name (default:
".") that Postfix may use to determine whether DNSSEC validation
is available.
<b><a href="postconf.5.html#known_tcp_ports">known_tcp_ports</a> (lmtp=24, smtp=25, smtps=submissions=465, submis-</b>
<b><a href="postconf.5.html#known_tcp_ports">known_tcp_ports</a> (lmtp=24, smtp=25, smtps=submissions=465, submis-</b>
<b>sion=587)</b>
Optional setting that avoids lookups in the <b>services</b>(5) data-
Optional setting that avoids lookups in the <b>services</b>(5) data-
base.
Available in Postfix version 3.7 and later:
<b><a href="postconf.5.html#smtp_per_request_deadline">smtp_per_request_deadline</a> (no)</b>
Change the behavior of the smtp_*_timeout time limits, from a
time limit per plaintext or TLS read or write call, to a com-
bined time limit for sending a complete SMTP request and for
Change the behavior of the smtp_*_timeout time limits, from a
time limit per plaintext or TLS read or write call, to a com-
bined time limit for sending a complete SMTP request and for
receiving a complete SMTP response.
<b><a href="postconf.5.html#smtp_min_data_rate">smtp_min_data_rate</a> (500)</b>
The minimum plaintext data transfer rate in bytes/second for
The minimum plaintext data transfer rate in bytes/second for
DATA requests, when deadlines are enabled with
<a href="postconf.5.html#smtp_per_request_deadline">smtp_per_request_deadline</a>.
@ -413,16 +411,16 @@ SMTP(8) SMTP(8)
Available in Postfix version 3.8 and later:
<b><a href="postconf.5.html#use_srv_lookup">use_srv_lookup</a> (empty)</b>
Enables discovery for the specified service(s) using DNS SRV
Enables discovery for the specified service(s) using DNS SRV
records.
<b><a href="postconf.5.html#ignore_srv_lookup_error">ignore_srv_lookup_error</a> (no)</b>
When SRV record lookup fails, fall back to MX or IP address
When SRV record lookup fails, fall back to MX or IP address
lookup as if SRV record lookup was not enabled.
<b><a href="postconf.5.html#allow_srv_lookup_fallback">allow_srv_lookup_fallback</a> (no)</b>
When SRV record lookup fails or no SRV record exists, fall back
to MX or IP address lookup as if SRV record lookup was not
When SRV record lookup fails or no SRV record exists, fall back
to MX or IP address lookup as if SRV record lookup was not
enabled.
<b><a name="mime_processing_controls">MIME PROCESSING CONTROLS</a></b>
@ -441,7 +439,7 @@ SMTP(8) SMTP(8)
Available in Postfix version 2.1 and later:
<b><a href="postconf.5.html#smtp_send_xforward_command">smtp_send_xforward_command</a> (no)</b>
Send the non-standard XFORWARD command when the Postfix SMTP
Send the non-standard XFORWARD command when the Postfix SMTP
server EHLO response announces XFORWARD support.
<b><a name="sasl_authentication_controls">SASL AUTHENTICATION CONTROLS</a></b>
@ -449,88 +447,88 @@ SMTP(8) SMTP(8)
Enable SASL authentication in the Postfix SMTP client.
<b><a href="postconf.5.html#smtp_sasl_password_maps">smtp_sasl_password_maps</a> (empty)</b>
Optional Postfix SMTP client lookup tables with one user-
name:password entry per sender, remote hostname or next-hop
Optional Postfix SMTP client lookup tables with one user-
name:password entry per sender, remote hostname or next-hop
domain.
<b><a href="postconf.5.html#smtp_sasl_security_options">smtp_sasl_security_options</a> (noplaintext, noanonymous)</b>
Postfix SMTP client SASL security options; as of Postfix 2.3 the
list of available features depends on the SASL client implemen-
list of available features depends on the SASL client implemen-
tation that is selected with <b><a href="postconf.5.html#smtp_sasl_type">smtp_sasl_type</a></b>.
Available in Postfix version 2.2 and later:
<b><a href="postconf.5.html#smtp_sasl_mechanism_filter">smtp_sasl_mechanism_filter</a> (empty)</b>
If non-empty, a Postfix SMTP client filter for the remote SMTP
If non-empty, a Postfix SMTP client filter for the remote SMTP
server's list of offered SASL mechanisms.
Available in Postfix version 2.3 and later:
<b><a href="postconf.5.html#smtp_sender_dependent_authentication">smtp_sender_dependent_authentication</a> (no)</b>
Enable sender-dependent authentication in the Postfix SMTP
client; this is available only with SASL authentication, and
disables SMTP connection caching to ensure that mail from dif-
client; this is available only with SASL authentication, and
disables SMTP connection caching to ensure that mail from dif-
ferent senders will use the appropriate credentials.
<b><a href="postconf.5.html#smtp_sasl_path">smtp_sasl_path</a> (empty)</b>
Implementation-specific information that the Postfix SMTP client
passes through to the SASL plug-in implementation that is
passes through to the SASL plug-in implementation that is
selected with <b><a href="postconf.5.html#smtp_sasl_type">smtp_sasl_type</a></b>.
<b><a href="postconf.5.html#smtp_sasl_type">smtp_sasl_type</a> (cyrus)</b>
The SASL plug-in type that the Postfix SMTP client should use
The SASL plug-in type that the Postfix SMTP client should use
for authentication.
Available in Postfix version 2.5 and later:
<b><a href="postconf.5.html#smtp_sasl_auth_cache_name">smtp_sasl_auth_cache_name</a> (empty)</b>
An optional table to prevent repeated SASL authentication fail-
ures with the same remote SMTP server hostname, username and
An optional table to prevent repeated SASL authentication fail-
ures with the same remote SMTP server hostname, username and
password.
<b><a href="postconf.5.html#smtp_sasl_auth_cache_time">smtp_sasl_auth_cache_time</a> (90d)</b>
The maximal age of an <a href="postconf.5.html#smtp_sasl_auth_cache_name">smtp_sasl_auth_cache_name</a> entry before it
The maximal age of an <a href="postconf.5.html#smtp_sasl_auth_cache_name">smtp_sasl_auth_cache_name</a> entry before it
is removed.
<b><a href="postconf.5.html#smtp_sasl_auth_soft_bounce">smtp_sasl_auth_soft_bounce</a> (yes)</b>
When a remote SMTP server rejects a SASL authentication request
with a 535 reply code, defer mail delivery instead of returning
When a remote SMTP server rejects a SASL authentication request
with a 535 reply code, defer mail delivery instead of returning
mail as undeliverable.
Available in Postfix version 2.9 and later:
<b><a href="postconf.5.html#smtp_send_dummy_mail_auth">smtp_send_dummy_mail_auth</a> (no)</b>
Whether or not to append the "AUTH=&lt;&gt;" option to the MAIL FROM
Whether or not to append the "AUTH=&lt;&gt;" option to the MAIL FROM
command in SASL-authenticated SMTP sessions.
Available in Postfix version 3.9 and later:
<b><a href="postconf.5.html#smtp_sasl_password_result_delimiter">smtp_sasl_password_result_delimiter</a> (:)</b>
The delimiter between username and password in sasl_passwd_maps
The delimiter between username and password in sasl_passwd_maps
lookup results.
<b><a name="tls_support_controls">TLS SUPPORT CONTROLS</a></b>
Detailed information about STARTTLS configuration may be found in the
Detailed information about STARTTLS configuration may be found in the
<a href="TLS_README.html">TLS_README</a> document.
<b><a href="postconf.5.html#smtp_tls_security_level">smtp_tls_security_level</a> (empty)</b>
The default SMTP TLS security level for the Postfix SMTP client.
<b><a href="postconf.5.html#smtp_sasl_tls_security_options">smtp_sasl_tls_security_options</a> ($<a href="postconf.5.html#smtp_sasl_security_options">smtp_sasl_security_options</a>)</b>
The SASL authentication security options that the Postfix SMTP
The SASL authentication security options that the Postfix SMTP
client uses for TLS encrypted SMTP sessions.
<b><a href="postconf.5.html#smtp_starttls_timeout">smtp_starttls_timeout</a> (300s)</b>
Time limit for Postfix SMTP client write and read operations
Time limit for Postfix SMTP client write and read operations
during TLS startup and shutdown handshake procedures.
<b><a href="postconf.5.html#smtp_tls_CAfile">smtp_tls_CAfile</a> (empty)</b>
A file containing CA certificates of root CAs trusted to sign
either remote SMTP server certificates or intermediate CA cer-
A file containing CA certificates of root CAs trusted to sign
either remote SMTP server certificates or intermediate CA cer-
tificates.
<b><a href="postconf.5.html#smtp_tls_CApath">smtp_tls_CApath</a> (empty)</b>
Directory with PEM format Certification Authority certificates
Directory with PEM format Certification Authority certificates
that the Postfix SMTP client uses to verify a remote SMTP server
certificate.
@ -538,7 +536,7 @@ SMTP(8) SMTP(8)
File with the Postfix SMTP client RSA certificate in PEM format.
<b><a href="postconf.5.html#smtp_tls_mandatory_ciphers">smtp_tls_mandatory_ciphers</a> (medium)</b>
The minimum TLS cipher grade that the Postfix SMTP client will
The minimum TLS cipher grade that the Postfix SMTP client will
use with mandatory TLS encryption.
<b><a href="postconf.5.html#smtp_tls_exclude_ciphers">smtp_tls_exclude_ciphers</a> (empty)</b>
@ -546,8 +544,8 @@ SMTP(8) SMTP(8)
client cipher list at all TLS security levels.
<b><a href="postconf.5.html#smtp_tls_mandatory_exclude_ciphers">smtp_tls_mandatory_exclude_ciphers</a> (empty)</b>
Additional list of ciphers or cipher types to exclude from the
Postfix SMTP client cipher list at mandatory TLS security lev-
Additional list of ciphers or cipher types to exclude from the
Postfix SMTP client cipher list at mandatory TLS security lev-
els.
<b><a href="postconf.5.html#smtp_tls_dcert_file">smtp_tls_dcert_file</a> (empty)</b>
@ -563,7 +561,7 @@ SMTP(8) SMTP(8)
Enable additional Postfix SMTP client logging of TLS activity.
<b><a href="postconf.5.html#smtp_tls_note_starttls_offer">smtp_tls_note_starttls_offer</a> (no)</b>
Log the hostname of a remote SMTP server that offers STARTTLS,
Log the hostname of a remote SMTP server that offers STARTTLS,
when TLS is not already enabled for that server.
<b><a href="postconf.5.html#smtp_tls_policy_maps">smtp_tls_policy_maps</a> (empty)</b>
@ -572,14 +570,14 @@ SMTP(8) SMTP(8)
fied, this overrides the obsolete <a href="postconf.5.html#smtp_tls_per_site">smtp_tls_per_site</a> parameter.
<b><a href="postconf.5.html#smtp_tls_mandatory_protocols">smtp_tls_mandatory_protocols</a> (see 'postconf -d' output)</b>
TLS protocols that the Postfix SMTP client will use with manda-
TLS protocols that the Postfix SMTP client will use with manda-
tory TLS encryption.
<b><a href="postconf.5.html#smtp_tls_scert_verifydepth">smtp_tls_scert_verifydepth</a> (9)</b>
The verification depth for remote SMTP server certificates.
<b><a href="postconf.5.html#smtp_tls_secure_cert_match">smtp_tls_secure_cert_match</a> (nexthop, dot-nexthop)</b>
How the Postfix SMTP client verifies the server certificate
How the Postfix SMTP client verifies the server certificate
peername for the "secure" TLS security level.
<b><a href="postconf.5.html#smtp_tls_session_cache_database">smtp_tls_session_cache_database</a> (empty)</b>
@ -587,16 +585,16 @@ SMTP(8) SMTP(8)
session cache.
<b><a href="postconf.5.html#smtp_tls_session_cache_timeout">smtp_tls_session_cache_timeout</a> (3600s)</b>
The expiration time of Postfix SMTP client TLS session cache
The expiration time of Postfix SMTP client TLS session cache
information.
<b><a href="postconf.5.html#smtp_tls_verify_cert_match">smtp_tls_verify_cert_match</a> (hostname)</b>
How the Postfix SMTP client verifies the server certificate
How the Postfix SMTP client verifies the server certificate
peername for the "verify" TLS security level.
<b><a href="postconf.5.html#tls_daemon_random_bytes">tls_daemon_random_bytes</a> (32)</b>
The number of pseudo-random bytes that an <a href="smtp.8.html"><b>smtp</b>(8)</a> or <a href="smtpd.8.html"><b>smtpd</b>(8)</a>
process requests from the <a href="tlsmgr.8.html"><b>tlsmgr</b>(8)</a> server in order to seed its
The number of pseudo-random bytes that an <a href="smtp.8.html"><b>smtp</b>(8)</a> or <a href="smtpd.8.html"><b>smtpd</b>(8)</a>
process requests from the <a href="tlsmgr.8.html"><b>tlsmgr</b>(8)</a> server in order to seed its
internal pseudo random number generator (PRNG).
<b><a href="postconf.5.html#tls_high_cipherlist">tls_high_cipherlist</a> (see 'postconf -d' output)</b>
@ -606,7 +604,7 @@ SMTP(8) SMTP(8)
The OpenSSL cipherlist for "medium" or higher grade ciphers.
<b><a href="postconf.5.html#tls_null_cipherlist">tls_null_cipherlist</a> (eNULL:!aNULL)</b>
The OpenSSL cipherlist for "NULL" grade ciphers that provide
The OpenSSL cipherlist for "NULL" grade ciphers that provide
authentication without encryption.
Available in in Postfix version 2.3..3.7:
@ -621,45 +619,45 @@ SMTP(8) SMTP(8)
<b><a href="postconf.5.html#smtp_sasl_tls_verified_security_options">smtp_sasl_tls_verified_security_options</a> ($<a href="postconf.5.html#smtp_sasl_tls_security_options">smtp_sasl_tls_secu</a>-</b>
<b><a href="postconf.5.html#smtp_sasl_tls_security_options">rity_options</a>)</b>
The SASL authentication security options that the Postfix SMTP
client uses for TLS encrypted SMTP sessions with a verified
The SASL authentication security options that the Postfix SMTP
client uses for TLS encrypted SMTP sessions with a verified
server certificate.
Available in Postfix version 2.5 and later:
<b><a href="postconf.5.html#smtp_tls_fingerprint_cert_match">smtp_tls_fingerprint_cert_match</a> (empty)</b>
List of acceptable remote SMTP server certificate fingerprints
for the "fingerprint" TLS security level (<b><a href="postconf.5.html#smtp_tls_security_level">smtp_tls_secu</a>-</b>
List of acceptable remote SMTP server certificate fingerprints
for the "fingerprint" TLS security level (<b><a href="postconf.5.html#smtp_tls_security_level">smtp_tls_secu</a>-</b>
<b><a href="postconf.5.html#smtp_tls_security_level">rity_level</a></b> = fingerprint).
<b><a href="postconf.5.html#smtp_tls_fingerprint_digest">smtp_tls_fingerprint_digest</a> (see 'postconf -d' output)</b>
The message digest algorithm used to construct remote SMTP
The message digest algorithm used to construct remote SMTP
server certificate fingerprints.
Available in Postfix version 2.6 and later:
<b><a href="postconf.5.html#smtp_tls_protocols">smtp_tls_protocols</a> (see 'postconf -d' output)</b>
TLS protocols that the Postfix SMTP client will use with oppor-
TLS protocols that the Postfix SMTP client will use with oppor-
tunistic TLS encryption.
<b><a href="postconf.5.html#smtp_tls_ciphers">smtp_tls_ciphers</a> (medium)</b>
The minimum TLS cipher grade that the Postfix SMTP client will
The minimum TLS cipher grade that the Postfix SMTP client will
use with opportunistic TLS encryption.
<b><a href="postconf.5.html#smtp_tls_eccert_file">smtp_tls_eccert_file</a> (empty)</b>
File with the Postfix SMTP client ECDSA certificate in PEM for-
File with the Postfix SMTP client ECDSA certificate in PEM for-
mat.
<b><a href="postconf.5.html#smtp_tls_eckey_file">smtp_tls_eckey_file</a> ($<a href="postconf.5.html#smtp_tls_eccert_file">smtp_tls_eccert_file</a>)</b>
File with the Postfix SMTP client ECDSA private key in PEM for-
File with the Postfix SMTP client ECDSA private key in PEM for-
mat.
Available in Postfix version 2.7 and later:
<b><a href="postconf.5.html#smtp_tls_block_early_mail_reply">smtp_tls_block_early_mail_reply</a> (no)</b>
Try to detect a mail hijacking attack based on a TLS protocol
vulnerability (CVE-2009-3555), where an attacker prepends mali-
cious HELO, MAIL, RCPT, DATA commands to a Postfix SMTP client
Try to detect a mail hijacking attack based on a TLS protocol
vulnerability (CVE-2009-3555), where an attacker prepends mali-
cious HELO, MAIL, RCPT, DATA commands to a Postfix SMTP client
TLS session.
Available in Postfix version 2.8 and later:
@ -679,11 +677,11 @@ SMTP(8) SMTP(8)
Available in Postfix version 2.11 and later:
<b><a href="postconf.5.html#smtp_tls_trust_anchor_file">smtp_tls_trust_anchor_file</a> (empty)</b>
Zero or more PEM-format files with trust-anchor certificates
Zero or more PEM-format files with trust-anchor certificates
and/or public keys.
<b><a href="postconf.5.html#smtp_tls_force_insecure_host_tlsa_lookup">smtp_tls_force_insecure_host_tlsa_lookup</a> (no)</b>
Lookup the associated DANE TLSA RRset even when a hostname is
Lookup the associated DANE TLSA RRset even when a hostname is
not an alias and its address records lie in an unsigned zone.
<b><a href="postconf.5.html#tlsmgr_service_name">tlsmgr_service_name</a> (tlsmgr)</b>
@ -692,20 +690,20 @@ SMTP(8) SMTP(8)
Available in Postfix version 3.0 and later:
<b><a href="postconf.5.html#smtp_tls_wrappermode">smtp_tls_wrappermode</a> (no)</b>
Request that the Postfix SMTP client connects using the SUBMIS-
Request that the Postfix SMTP client connects using the SUBMIS-
SIONS/SMTPS protocol instead of using the STARTTLS command.
Available in Postfix version 3.1 and later:
<b><a href="postconf.5.html#smtp_tls_dane_insecure_mx_policy">smtp_tls_dane_insecure_mx_policy</a> (see 'postconf -d' output)</b>
The TLS policy for MX hosts with "secure" TLSA records when the
nexthop destination security level is <b>dane</b>, but the MX record
The TLS policy for MX hosts with "secure" TLSA records when the
nexthop destination security level is <b>dane</b>, but the MX record
was found via an "insecure" MX lookup.
Available in Postfix version 3.2 and later:
<b><a href="postconf.5.html#tls_eecdh_auto_curves">tls_eecdh_auto_curves</a> (see 'postconf -d' output)</b>
The prioritized list of elliptic curves, that should be enabled
The prioritized list of elliptic curves, that should be enabled
in the Postfix SMTP client and server.
Available in Postfix version 3.4 and later:
@ -714,23 +712,23 @@ SMTP(8) SMTP(8)
Try to make multiple deliveries per TLS-encrypted connection.
<b><a href="postconf.5.html#smtp_tls_chain_files">smtp_tls_chain_files</a> (empty)</b>
List of one or more PEM files, each holding one or more private
List of one or more PEM files, each holding one or more private
keys directly followed by a corresponding certificate chain.
<b><a href="postconf.5.html#smtp_tls_servername">smtp_tls_servername</a> (empty)</b>
Optional name to send to the remote SMTP server in the TLS
Optional name to send to the remote SMTP server in the TLS
Server Name Indication (SNI) extension.
Available in Postfix 3.5, 3.4.6, 3.3.5, 3.2.10, 3.1.13 and later:
<b><a href="postconf.5.html#tls_fast_shutdown_enable">tls_fast_shutdown_enable</a> (yes)</b>
A workaround for implementations that hang Postfix while shut-
A workaround for implementations that hang Postfix while shut-
ting down a TLS session, until Postfix times out.
Available in Postfix version 3.8 and later:
<b><a href="postconf.5.html#tls_ffdhe_auto_groups">tls_ffdhe_auto_groups</a> (see 'postconf -d' output)</b>
The prioritized list of finite-field Diffie-Hellman ephemeral
The prioritized list of finite-field Diffie-Hellman ephemeral
(FFDHE) key exchange groups supported by the Postfix SMTP client
and server.
@ -740,15 +738,17 @@ SMTP(8) SMTP(8)
Optional configuration file with baseline OpenSSL settings.
<b><a href="postconf.5.html#tls_config_name">tls_config_name</a> (empty)</b>
The application name passed by Postfix to OpenSSL library ini-
The application name passed by Postfix to OpenSSL library ini-
tialization functions.
Available in Postfix version 3.9 and later:
<b><a href="postconf.5.html#smtp_tls_enable_rpk">smtp_tls_enable_rpk</a> (no)</b>
Request that remote SMTP servers send an <a href="https://tools.ietf.org/html/rfc7250">RFC7250</a> raw public key
Request that remote SMTP servers send an <a href="https://tools.ietf.org/html/rfc7250">RFC7250</a> raw public key
instead of an X.509 certificate.
Available in Postfix version 3.10 and later:
<b><a href="postconf.5.html#smtp_tlsrpt_enable">smtp_tlsrpt_enable</a> (no)</b>
Enable support for <a href="https://tools.ietf.org/html/rfc8460">RFC 8460</a> TLSRPT notifications.
@ -758,48 +758,48 @@ SMTP(8) SMTP(8)
<b><a href="postconf.5.html#smtp_tlsrpt_skip_reused_handshakes">smtp_tlsrpt_skip_reused_handshakes</a> (yes)</b>
Do not report the TLSRPT status for TLS protocol handshakes that
reuse a previously-negotiated TLS session (there is no new
reuse a previously-negotiated TLS session (there is no new
information to report).
<b><a href="postconf.5.html#requiretls_enable">requiretls_enable</a> (yes)</b>
Enable support for the ESMTP verb "REQUIRETLS", defined in <a href="https://tools.ietf.org/html/rfc8689">RFC</a>
Enable support for the ESMTP verb "REQUIRETLS", defined in <a href="https://tools.ietf.org/html/rfc8689">RFC</a>
<a href="https://tools.ietf.org/html/rfc8689">8689</a>.
<b><a name="obsolete_tls_controls">OBSOLETE TLS CONTROLS</a></b>
The following configuration parameters exist for compatibility with
Postfix versions before 2.3. Support for these will be removed in a
The following configuration parameters exist for compatibility with
Postfix versions before 2.3. Support for these will be removed in a
future release.
<b><a href="postconf.5.html#smtp_use_tls">smtp_use_tls</a> (no)</b>
Opportunistic mode: use TLS when a remote SMTP server announces
Opportunistic mode: use TLS when a remote SMTP server announces
STARTTLS support, otherwise send the mail in the clear.
<b><a href="postconf.5.html#smtp_enforce_tls">smtp_enforce_tls</a> (no)</b>
Enforcement mode: require that remote SMTP servers use TLS
Enforcement mode: require that remote SMTP servers use TLS
encryption, and never send mail in the clear.
<b><a href="postconf.5.html#smtp_tls_enforce_peername">smtp_tls_enforce_peername</a> (yes)</b>
With mandatory TLS encryption, require that the remote SMTP
server hostname matches the information in the remote SMTP
With mandatory TLS encryption, require that the remote SMTP
server hostname matches the information in the remote SMTP
server certificate.
<b><a href="postconf.5.html#smtp_tls_per_site">smtp_tls_per_site</a> (empty)</b>
Optional lookup tables with the Postfix SMTP client TLS usage
policy by next-hop destination and by remote SMTP server host-
Optional lookup tables with the Postfix SMTP client TLS usage
policy by next-hop destination and by remote SMTP server host-
name.
<b><a href="postconf.5.html#smtp_tls_cipherlist">smtp_tls_cipherlist</a> (empty)</b>
Obsolete Postfix &lt; 2.3 control for the Postfix SMTP client TLS
Obsolete Postfix &lt; 2.3 control for the Postfix SMTP client TLS
cipher list.
<b><a name="resource_and_rate_controls">RESOURCE AND RATE CONTROLS</a></b>
<b><a href="postconf.5.html#smtp_connect_timeout">smtp_connect_timeout</a> (30s)</b>
The Postfix SMTP client time limit for completing a TCP connec-
The Postfix SMTP client time limit for completing a TCP connec-
tion, or zero (use the operating system built-in time limit).
<b><a href="postconf.5.html#smtp_helo_timeout">smtp_helo_timeout</a> (300s)</b>
The Postfix SMTP client time limit for sending the HELO or EHLO
command, and for receiving the initial remote SMTP server
The Postfix SMTP client time limit for sending the HELO or EHLO
command, and for receiving the initial remote SMTP server
response.
<b><a href="postconf.5.html#lmtp_lhlo_timeout">lmtp_lhlo_timeout</a> (300s)</b>
@ -811,19 +811,19 @@ SMTP(8) SMTP(8)
mand, and for receiving the remote SMTP server response.
<b><a href="postconf.5.html#smtp_mail_timeout">smtp_mail_timeout</a> (300s)</b>
The Postfix SMTP client time limit for sending the MAIL FROM
The Postfix SMTP client time limit for sending the MAIL FROM
command, and for receiving the remote SMTP server response.
<b><a href="postconf.5.html#smtp_rcpt_timeout">smtp_rcpt_timeout</a> (300s)</b>
The Postfix SMTP client time limit for sending the SMTP RCPT TO
The Postfix SMTP client time limit for sending the SMTP RCPT TO
command, and for receiving the remote SMTP server response.
<b><a href="postconf.5.html#smtp_data_init_timeout">smtp_data_init_timeout</a> (120s)</b>
The Postfix SMTP client time limit for sending the SMTP DATA
The Postfix SMTP client time limit for sending the SMTP DATA
command, and for receiving the remote SMTP server response.
<b><a href="postconf.5.html#smtp_data_xfer_timeout">smtp_data_xfer_timeout</a> (180s)</b>
The Postfix SMTP client time limit for sending the SMTP message
The Postfix SMTP client time limit for sending the SMTP message
content.
<b><a href="postconf.5.html#smtp_data_done_timeout">smtp_data_done_timeout</a> (600s)</b>
@ -837,13 +837,13 @@ SMTP(8) SMTP(8)
Available in Postfix version 2.1 and later:
<b><a href="postconf.5.html#smtp_mx_address_limit">smtp_mx_address_limit</a> (5)</b>
The maximal number of MX (mail exchanger) IP addresses that can
result from Postfix SMTP client mail exchanger lookups, or zero
The maximal number of MX (mail exchanger) IP addresses that can
result from Postfix SMTP client mail exchanger lookups, or zero
(no limit).
<b><a href="postconf.5.html#smtp_mx_session_limit">smtp_mx_session_limit</a> (2)</b>
The maximal number of SMTP sessions per delivery request before
the Postfix SMTP client gives up or delivers to a fall-back
The maximal number of SMTP sessions per delivery request before
the Postfix SMTP client gives up or delivers to a fall-back
<a href="postconf.5.html#relayhost">relay host</a>, or zero (no limit).
<b><a href="postconf.5.html#smtp_rset_timeout">smtp_rset_timeout</a> (20s)</b>
@ -853,17 +853,17 @@ SMTP(8) SMTP(8)
Available in Postfix version 2.2 and earlier:
<b><a href="postconf.5.html#lmtp_cache_connection">lmtp_cache_connection</a> (yes)</b>
Keep Postfix LMTP client connections open for up to $<a href="postconf.5.html#max_idle">max_idle</a>
Keep Postfix LMTP client connections open for up to $<a href="postconf.5.html#max_idle">max_idle</a>
seconds.
Available in Postfix version 2.2 and later:
<b><a href="postconf.5.html#smtp_connection_cache_destinations">smtp_connection_cache_destinations</a> (empty)</b>
Permanently enable SMTP connection caching for the specified
Permanently enable SMTP connection caching for the specified
destinations.
<b><a href="postconf.5.html#smtp_connection_cache_on_demand">smtp_connection_cache_on_demand</a> (yes)</b>
Temporarily enable SMTP connection caching while a destination
Temporarily enable SMTP connection caching while a destination
has a high volume of mail in the <a href="QSHAPE_README.html#active_queue">active queue</a>.
<b><a href="postconf.5.html#smtp_connection_reuse_time_limit">smtp_connection_reuse_time_limit</a> (300s)</b>
@ -877,23 +877,23 @@ SMTP(8) SMTP(8)
Available in Postfix version 2.3 and later:
<b><a href="postconf.5.html#connection_cache_protocol_timeout">connection_cache_protocol_timeout</a> (5s)</b>
Time limit for connection cache connect, send or receive opera-
Time limit for connection cache connect, send or receive opera-
tions.
Available in Postfix version 2.9 - 3.6:
<b><a href="postconf.5.html#smtp_per_record_deadline">smtp_per_record_deadline</a> (no)</b>
Change the behavior of the smtp_*_timeout time limits, from a
time limit per read or write system call, to a time limit to
send or receive a complete record (an SMTP command line, SMTP
response line, SMTP message content line, or TLS protocol mes-
Change the behavior of the smtp_*_timeout time limits, from a
time limit per read or write system call, to a time limit to
send or receive a complete record (an SMTP command line, SMTP
response line, SMTP message content line, or TLS protocol mes-
sage).
Available in Postfix version 2.11 and later:
<b><a href="postconf.5.html#smtp_connection_reuse_count_limit">smtp_connection_reuse_count_limit</a> (0)</b>
When SMTP connection caching is enabled, the number of times
that an SMTP session may be reused before it is closed, or zero
When SMTP connection caching is enabled, the number of times
that an SMTP session may be reused before it is closed, or zero
(no limit).
Available in Postfix version 3.4 and later:
@ -904,13 +904,13 @@ SMTP(8) SMTP(8)
Available in Postfix version 3.7 and later:
<b><a href="postconf.5.html#smtp_per_request_deadline">smtp_per_request_deadline</a> (no)</b>
Change the behavior of the smtp_*_timeout time limits, from a
time limit per plaintext or TLS read or write call, to a com-
bined time limit for sending a complete SMTP request and for
Change the behavior of the smtp_*_timeout time limits, from a
time limit per plaintext or TLS read or write call, to a com-
bined time limit for sending a complete SMTP request and for
receiving a complete SMTP response.
<b><a href="postconf.5.html#smtp_min_data_rate">smtp_min_data_rate</a> (500)</b>
The minimum plaintext data transfer rate in bytes/second for
The minimum plaintext data transfer rate in bytes/second for
DATA requests, when deadlines are enabled with
<a href="postconf.5.html#smtp_per_request_deadline">smtp_per_request_deadline</a>.
@ -918,54 +918,54 @@ SMTP(8) SMTP(8)
<b><a href="postconf.5.html#transport_destination_concurrency_limit">transport_destination_concurrency_limit</a> ($<a href="postconf.5.html#default_destination_concurrency_limit">default_destination_concur</a>-</b>
<b><a href="postconf.5.html#default_destination_concurrency_limit">rency_limit</a>)</b>
A transport-specific override for the <a href="postconf.5.html#default_destination_concurrency_limit">default_destination_con</a>-
A transport-specific override for the <a href="postconf.5.html#default_destination_concurrency_limit">default_destination_con</a>-
<a href="postconf.5.html#default_destination_concurrency_limit">currency_limit</a> parameter value, where <i>transport</i> is the <a href="master.5.html">master.cf</a>
name of the message delivery transport.
<b><a href="postconf.5.html#transport_destination_recipient_limit">transport_destination_recipient_limit</a> ($<a href="postconf.5.html#default_destination_recipient_limit">default_destination_recipi</a>-</b>
<b><a href="postconf.5.html#default_destination_recipient_limit">ent_limit</a>)</b>
A transport-specific override for the <a href="postconf.5.html#default_destination_recipient_limit">default_destination_recip</a>-
<a href="postconf.5.html#default_destination_recipient_limit">ient_limit</a> parameter value, where <i>transport</i> is the <a href="master.5.html">master.cf</a>
<a href="postconf.5.html#default_destination_recipient_limit">ient_limit</a> parameter value, where <i>transport</i> is the <a href="master.5.html">master.cf</a>
name of the message delivery transport.
<b><a name="smtputf8_controls">SMTPUTF8 CONTROLS</a></b>
Preliminary SMTPUTF8 support is introduced with Postfix 3.0.
<b><a href="postconf.5.html#smtputf8_enable">smtputf8_enable</a> (yes)</b>
Enable preliminary SMTPUTF8 support for the protocols described
Enable preliminary SMTPUTF8 support for the protocols described
in <a href="https://tools.ietf.org/html/rfc6531">RFC 6531</a>, <a href="https://tools.ietf.org/html/rfc6532">RFC 6532</a>, and <a href="https://tools.ietf.org/html/rfc6533">RFC 6533</a>.
<b><a href="postconf.5.html#smtputf8_autodetect_classes">smtputf8_autodetect_classes</a> (sendmail, verify)</b>
Detect that a message requires SMTPUTF8 support for the speci-
Detect that a message requires SMTPUTF8 support for the speci-
fied mail origin classes.
Available in Postfix version 3.2 and later:
<b><a href="postconf.5.html#enable_idna2003_compatibility">enable_idna2003_compatibility</a> (no)</b>
Enable 'transitional' compatibility between IDNA2003 and
IDNA2008, when converting UTF-8 domain names to/from the ASCII
Enable 'transitional' compatibility between IDNA2003 and
IDNA2008, when converting UTF-8 domain names to/from the ASCII
form that is used for DNS lookups.
<b><a name="trouble_shooting_controls">TROUBLE SHOOTING CONTROLS</a></b>
<b><a href="postconf.5.html#debug_peer_level">debug_peer_level</a> (2)</b>
The increment in verbose logging level when a nexthop destina-
tion, remote client or server name or network address matches a
The increment in verbose logging level when a nexthop destina-
tion, remote client or server name or network address matches a
pattern given with the <a href="postconf.5.html#debug_peer_list">debug_peer_list</a> parameter.
<b><a href="postconf.5.html#debug_peer_list">debug_peer_list</a> (empty)</b>
Optional list of nexthop destination, remote client or server
name or network address patterns that, if matched, cause the
verbose logging level to increase by the amount specified in
Optional list of nexthop destination, remote client or server
name or network address patterns that, if matched, cause the
verbose logging level to increase by the amount specified in
$<a href="postconf.5.html#debug_peer_level">debug_peer_level</a>.
<b><a href="postconf.5.html#error_notice_recipient">error_notice_recipient</a> (postmaster)</b>
The recipient of postmaster notifications about mail delivery
The recipient of postmaster notifications about mail delivery
problems that are caused by policy, resource, software or proto-
col errors.
<b><a href="postconf.5.html#internal_mail_filter_classes">internal_mail_filter_classes</a> (empty)</b>
What categories of Postfix-generated mail are subject to
before-queue content inspection by <a href="postconf.5.html#non_smtpd_milters">non_smtpd_milters</a>,
What categories of Postfix-generated mail are subject to
before-queue content inspection by <a href="postconf.5.html#non_smtpd_milters">non_smtpd_milters</a>,
<a href="postconf.5.html#header_checks">header_checks</a> and <a href="postconf.5.html#body_checks">body_checks</a>.
<b><a href="postconf.5.html#notify_classes">notify_classes</a> (resource, software)</b>
@ -973,46 +973,46 @@ SMTP(8) SMTP(8)
<b><a name="miscellaneous_controls">MISCELLANEOUS CONTROLS</a></b>
<b><a href="postconf.5.html#best_mx_transport">best_mx_transport</a> (empty)</b>
Where the Postfix SMTP client should deliver mail when it
Where the Postfix SMTP client should deliver mail when it
detects a "mail loops back to myself" error condition.
<b><a href="postconf.5.html#config_directory">config_directory</a> (see 'postconf -d' output)</b>
The default location of the Postfix <a href="postconf.5.html">main.cf</a> and <a href="master.5.html">master.cf</a> con-
The default location of the Postfix <a href="postconf.5.html">main.cf</a> and <a href="master.5.html">master.cf</a> con-
figuration files.
<b><a href="postconf.5.html#daemon_timeout">daemon_timeout</a> (18000s)</b>
How much time a Postfix daemon process may take to handle a
How much time a Postfix daemon process may take to handle a
request before it is terminated by a built-in watchdog timer.
<b><a href="postconf.5.html#delay_logging_resolution_limit">delay_logging_resolution_limit</a> (2)</b>
The maximal number of digits after the decimal point when log-
The maximal number of digits after the decimal point when log-
ging delay values.
<b><a href="postconf.5.html#disable_dns_lookups">disable_dns_lookups</a> (no)</b>
Disable DNS lookups in the Postfix SMTP and LMTP clients.
<b><a href="postconf.5.html#inet_interfaces">inet_interfaces</a> (all)</b>
The local network interface addresses that this mail system
The local network interface addresses that this mail system
receives mail on.
<b><a href="postconf.5.html#inet_protocols">inet_protocols</a> (see 'postconf -d' output)</b>
The Internet protocols Postfix will attempt to use when making
The Internet protocols Postfix will attempt to use when making
or accepting connections.
<b><a href="postconf.5.html#ipc_timeout">ipc_timeout</a> (3600s)</b>
The time limit for sending or receiving information over an
The time limit for sending or receiving information over an
internal communication channel.
<b><a href="postconf.5.html#lmtp_assume_final">lmtp_assume_final</a> (no)</b>
When a remote LMTP server announces no DSN support, assume that
the server performs final delivery, and send "delivered" deliv-
When a remote LMTP server announces no DSN support, assume that
the server performs final delivery, and send "delivered" deliv-
ery status notifications instead of "relayed".
<b><a href="postconf.5.html#lmtp_tcp_port">lmtp_tcp_port</a> (24)</b>
The default TCP port that the Postfix LMTP client connects to.
<b><a href="postconf.5.html#max_idle">max_idle</a> (100s)</b>
The maximum amount of time that an idle Postfix daemon process
The maximum amount of time that an idle Postfix daemon process
waits for an incoming connection before terminating voluntarily.
<b><a href="postconf.5.html#max_use">max_use</a> (100)</b>
@ -1026,21 +1026,21 @@ SMTP(8) SMTP(8)
The process name of a Postfix command or daemon process.
<b><a href="postconf.5.html#proxy_interfaces">proxy_interfaces</a> (empty)</b>
The remote network interface addresses that this mail system
receives mail on by way of a proxy or network address transla-
The remote network interface addresses that this mail system
receives mail on by way of a proxy or network address transla-
tion unit.
<b><a href="postconf.5.html#smtp_address_preference">smtp_address_preference</a> (any)</b>
The address type ("ipv6", "ipv4" or "any") that the Postfix SMTP
client will try first, when a destination has IPv6 and IPv4
client will try first, when a destination has IPv6 and IPv4
addresses with equal MX preference.
<b><a href="postconf.5.html#smtp_bind_address">smtp_bind_address</a> (empty)</b>
An optional numerical network address that the Postfix SMTP
An optional numerical network address that the Postfix SMTP
client should bind to when making an IPv4 connection.
<b><a href="postconf.5.html#smtp_bind_address6">smtp_bind_address6</a> (empty)</b>
An optional numerical network address that the Postfix SMTP
An optional numerical network address that the Postfix SMTP
client should bind to when making an IPv6 connection.
<b><a href="postconf.5.html#smtp_helo_name">smtp_helo_name</a> ($<a href="postconf.5.html#myhostname">myhostname</a>)</b>
@ -1060,7 +1060,7 @@ SMTP(8) SMTP(8)
The syslog facility of Postfix logging.
<b><a href="postconf.5.html#syslog_name">syslog_name</a> (see 'postconf -d' output)</b>
A prefix that is prepended to the process name in syslog
A prefix that is prepended to the process name in syslog
records, so that, for example, "smtpd" becomes "prefix/smtpd".
Available with Postfix 2.2 and earlier:
@ -1072,14 +1072,14 @@ SMTP(8) SMTP(8)
Available with Postfix 2.3 and later:
<b><a href="postconf.5.html#smtp_fallback_relay">smtp_fallback_relay</a> ($<a href="postconf.5.html#fallback_relay">fallback_relay</a>)</b>
Optional list of relay destinations that will be used when an
SMTP destination is not found, or when delivery fails due to a
Optional list of relay destinations that will be used when an
SMTP destination is not found, or when delivery fails due to a
non-permanent error.
Available with Postfix 3.0 and later:
<b><a href="postconf.5.html#smtp_address_verify_target">smtp_address_verify_target</a> (rcpt)</b>
In the context of email address verification, the SMTP protocol
In the context of email address verification, the SMTP protocol
stage that determines whether an email address is deliverable.
Available with Postfix 3.1 and later:
@ -1101,7 +1101,7 @@ SMTP(8) SMTP(8)
Available in Postfix 3.7 and later:
<b><a href="postconf.5.html#smtp_bind_address_enforce">smtp_bind_address_enforce</a> (no)</b>
Defer delivery when the Postfix SMTP client cannot apply the
Defer delivery when the Postfix SMTP client cannot apply the
<a href="postconf.5.html#smtp_bind_address">smtp_bind_address</a> or <a href="postconf.5.html#smtp_bind_address6">smtp_bind_address6</a> setting.
<b><a name="see_also">SEE ALSO</a></b>

16
postfix/man/man5/postconf.5
View File

@ -6581,13 +6581,15 @@ the mail server (IMPORTING HOME DIRECTORIES IS NOT RECOMMENDED).
.SH requiretls_enable (default: yes)
Enable support for the ESMTP verb "REQUIRETLS", defined in RFC
8689. By issuing this verb in the "MAIL FROM" command, a sender
requires that a message must be delivered over TLS connections with
a verified server certificate. This corresponds to the Postfix SMTP
client TLS security levels "secure", "verify", "fingerprint",
opportunistic "dane" with a successful certificate match, or
"dane\-only" (the postfix\-mta\-sts\-resolver plugin tells Postfix to
enforce a "secure with certificate match" policy). Otherwise, Postfix
returns the message as undeliverable.
specifies that a message must be delivered over TLS connections
with a verified server certificate, to a server that announces
"REQUIRETLS" support. This corresponds to the Postfix SMTP client
TLS security levels "secure", "verify", "fingerprint", dane\-only,
or opportunistic "dane", with a successful certificate match. The
Postfix SMTP client will try one or more servers, controlled with
the smtp_mx_address_limit parameter, until it finds a server that
satisfies requirements. Otherwise, Postfix returns the message as
undeliverable.
.PP
Note: REQUIRETLS overrides "TLS\-Required: no".
.PP

9
postfix/man/man8/smtp.8
View File

@ -153,11 +153,9 @@ This feature is available as of Postfix 3.5.
Indicates that the delivery is final. This flag affects
the status reported in "success" DSN (delivery status
notification) messages, and changes it from "relayed" into
"delivered". The flag also suppresses the requirement that
the remote server announces REQUIRETLS support.
"delivered".
.sp
This feature is available as of Postfix 3.5;
REQUIRETLS support was introduced with Postfix 3.10.
This feature is available as of Postfix 3.5.
.RE
.SH "SECURITY"
.na
@ -675,7 +673,8 @@ Available in Postfix version 3.9 and later:
.IP "\fBsmtp_tls_enable_rpk (no)\fR"
Request that remote SMTP servers send an RFC7250 raw public key
instead of an X.509 certificate.
.PP Available in Postfix version 3.10 and later:
.PP
Available in Postfix version 3.10 and later:
.IP "\fBsmtp_tlsrpt_enable (no)\fR"
Enable support for RFC 8460 TLSRPT notifications.
.IP "\fBsmtp_tlsrpt_socket_name (empty)\fR"

16
postfix/proto/postconf.proto
View File

@ -19491,13 +19491,15 @@ certificates, and fall back to plaintext if TLS is unavailable.
<p> Enable support for the ESMTP verb "REQUIRETLS", defined in RFC
8689. By issuing this verb in the "MAIL FROM" command, a sender
requires that a message must be delivered over TLS connections with
a verified server certificate. This corresponds to the Postfix SMTP
client TLS security levels "secure", "verify", "fingerprint",
opportunistic "dane" with a successful certificate match, or
"dane-only" (the postfix-mta-sts-resolver plugin tells Postfix to
enforce a "secure with certificate match" policy). Otherwise, Postfix
returns the message as undeliverable. </p>
specifies that a message must be delivered over TLS connections
with a verified server certificate, to a server that announces
"REQUIRETLS" support. This corresponds to the Postfix SMTP client
TLS security levels "secure", "verify", "fingerprint", dane-only,
or opportunistic "dane", with a successful certificate match. The
Postfix SMTP client will try one or more servers, controlled with
the smtp_mx_address_limit parameter, until it finds a server that
satisfies requirements. Otherwise, Postfix returns the message as
undeliverable. </p>
<p> Note: REQUIRETLS overrides "TLS-Required: no". </p>

2
postfix/src/cleanup/cleanup_api.c
View File

@ -81,7 +81,7 @@
/* Autodetection: request SMTPUTF8 support if the message
/* contains an UTF8 message header, sender, or recipient.
/* .IP CLEANUP_FLAG_REQUIRETLS
/* The sender requested 'authenticated' TLS enforcement.
/* The sender requested REQUIRETLS (RFC 8689) enforcement.
/* DIAGNOSTICS
/* Problems and transactions are logged to \fBsyslogd\fR(8)
/* or \fBpostlogd\fR(8).

2
postfix/src/global/mail_version.h
View File

@ -20,7 +20,7 @@
* Patches change both the patchlevel and the release date. Snapshots have no
* patchlevel; they change the release date only.
*/
#define MAIL_RELEASE_DATE "20250122"
#define MAIL_RELEASE_DATE "20250126"
#define MAIL_VERSION_NUMBER "3.10"
#ifdef SNAPSHOT

9
postfix/src/smtp/smtp.c
View File

@ -139,11 +139,9 @@
/* Indicates that the delivery is final. This flag affects
/* the status reported in "success" DSN (delivery status
/* notification) messages, and changes it from "relayed" into
/* "delivered". The flag also suppresses the requirement that
/* the remote server announces REQUIRETLS support.
/* "delivered".
/* .sp
/* This feature is available as of Postfix 3.5;
/* REQUIRETLS support was introduced with Postfix 3.10.
/* This feature is available as of Postfix 3.5.
/* .RE
/* SECURITY
/* .ad
@ -641,7 +639,8 @@
/* .IP "\fBsmtp_tls_enable_rpk (no)\fR"
/* Request that remote SMTP servers send an RFC7250 raw public key
/* instead of an X.509 certificate.
/* .PP Available in Postfix version 3.10 and later:
/* .PP
/* Available in Postfix version 3.10 and later:
/* .IP "\fBsmtp_tlsrpt_enable (no)\fR"
/* Enable support for RFC 8460 TLSRPT notifications.
/* .IP "\fBsmtp_tlsrpt_socket_name (empty)\fR"

3
postfix/src/smtp/smtp_connect.c
View File

@ -518,7 +518,8 @@ static int smtp_get_effective_tls_level(DSN_BUF *why, SMTP_STATE *state)
* If the sender requires TLS with server certificate verification, the
* TLS level must enforce a server certificate match.
*/
else if ((state->request->sendopts & SOPT_REQUIRETLS_ESMTP)) {
else if (var_requiretls_enable
&& (state->request->sendopts & SOPT_REQUIRETLS_ESMTP)) {
if (TLS_MUST_MATCH(tls->level) == 0) {
dsb_simple(why, "5.7.10", "Sender requires a TLS server "
"certificate match, but the configured %s TLS "

30
postfix/src/smtp/smtp_proto.c
View File

@ -685,23 +685,15 @@ int smtp_helo(SMTP_STATE *state)
}
/*
* If delivery of a REQUIRETLS message is not final, require that the
* server announces REQUIRETLS when the sender requested REQUIRETLS.
* Return the message as undeliverable only when there are no more
* alternative MX hosts.
*
* If delivery of a REQUIRETLS message is final, we don't need the server to
* announce REQUIRETLS support (but we still had to enforce the
* requirement that the TLS session has a matched server certificate).
* Require that the server announces REQUIRETLS when the sender requested
* REQUIRETLS. Return the message as undeliverable only when there are no
* more alternative MX hosts.
*/
#define SERVER_MUST_OFFER_REQUIRETLS \
((request->sendopts & SOPT_REQUIRETLS_ESMTP) != 0 \
&& (smtp_cli_attr.flags & SMTP_CLI_FLAG_FINAL_DELIVERY) == 0)
#ifdef USE_TLS
if ((state->misc_flags & SMTP_MISC_FLAG_IN_STARTTLS) != 0
&& (session->features & SMTP_FEATURE_REQUIRETLS) == 0
&& SERVER_MUST_OFFER_REQUIRETLS)
if (var_requiretls_enable
&& (request->sendopts & SOPT_REQUIRETLS_ESMTP) != 0
&& (state->misc_flags & SMTP_MISC_FLAG_IN_STARTTLS) != 0
&& (session->features & SMTP_FEATURE_REQUIRETLS) == 0)
return (smtp_misc_fail(state, SMTP_MISC_FAIL_SOFT_NON_FINAL,
DSN_BY_LOCAL_MTA,
SMTP_RESP_FAKE(&fake, "5.7.30"),
@ -1227,7 +1219,8 @@ static int smtp_start_tls(SMTP_STATE *state)
* REQUIRETLS. Return the message as undeliverable only when
* there are no more alternative MX hosts.
*/
if ((state->request->sendopts & SOPT_REQUIRETLS_ESMTP)) {
if (var_requiretls_enable
&& (state->request->sendopts & SOPT_REQUIRETLS_ESMTP)) {
return (smtp_misc_fail(state, SMTP_MISC_FAIL_SOFT_NON_FINAL,
DSN_BY_LOCAL_MTA,
SMTP_RESP_FAKE(&fake, "5.7.10"),
@ -1833,10 +1826,11 @@ static int smtp_loop(SMTP_STATE *state, NOCLOBBER int send_state,
* REQUIRETLS and the sender requested REQUIRETLS.
*/
#ifdef USE_TLS
if ((request->sendopts & SOPT_REQUIRETLS_ESMTP) != 0) {
if (var_requiretls_enable
&& (request->sendopts & SOPT_REQUIRETLS_ESMTP) != 0) {
if ((session->features & SMTP_FEATURE_REQUIRETLS) != 0)
vstring_strcat(next_command, " REQUIRETLS");
else if (SERVER_MUST_OFFER_REQUIRETLS)
else if ((request->sendopts & SOPT_REQUIRETLS_ESMTP) != 0)
msg_panic("Can't happen: message requires REQUIRETLS, but "
"host %s did not announce REQUIRETLS support",
session->namaddr);