Newaliases

sendmail - Postfix to Sendmail compatibility interface

Beschreibung

The Postfix sendmail(1) command implements the Postfix to Sendmail compatibility interface. For the sake of compatibility with existing applica‐ tions, some Sendmail command-line options are recognized but silently ignored.

By default, Postfix sendmail(1) reads a message from standard input until EOF or until it reads a line with only a . character, and arranges for de‐ livery. Postfix sendmail(1) relies on the postdrop(1) command to create a queue file in the maildrop directory.

Specific command aliases are provided for other common modes of operation:

mailq List the mail queue. Each entry shows the queue file ID, message size, arrival time, sender, and the recipients that still need to be deliv‐ ered. If mail could not be delivered upon the last attempt, the reason for failure is shown. The queue ID string is followed by an optional status character:

* The message is in the active queue, i.e. the message is selected for delivery.
! The message is in the hold queue, i.e. no further delivery attempt will be made until the mail is taken off hold.
# The message is forced to expire. See the postsuper(1) options -e or -f.

This mode of operation is implemented by executing the postqueue(1) command.

Syntax

sendmail [option ...] [recipient ...]
mailq sendmail -bp
newaliases sendmail -I

Konfiguration

Options

-Am (ignored)

-Ac (ignored) Postfix sendmail uses the same configuration file regardless of whether or not a message is an initial submission.

-B body_type The message body MIME type: 7BIT or 8BITMIME.

-bd Go into daemon mode. This mode of operation is implemented by executing the "postfix start" command.

-bh (ignored)

-bH (ignored) Postfix has no persistent host status database.

-bi Initialize alias database. See the newaliases command above.

-bl Go into daemon mode. To accept only local connections as with Sendmail´s -bl option, specify "inet_interfaces = loopback" in the Postfix main.cf configuration file.

-bm Read mail from standard input and arrange for delivery. This is the default mode of operation.

-bp List the mail queue. See the mailq command above.

-bs Stand-alone SMTP server mode. Read SMTP commands from standard input, and write responses to standard output. In stand-alone SMTP server mode, mail relaying and other access controls are disabled by default. To enable them, run the process as the mail_owner user.

This mode of operation is implemented by running the smtpd(8) daemon.

-bv Do not collect or deliver a message. Instead, send an email report after verifying each recipient address. This is useful for testing address rewriting and routing configurations.

This feature is available in Postfix version 2.1 and later.

-C config_file

-C config_dir The path name of the Postfix main.cf file, or of its parent directory. This information is ignored with Postfix versions before 2.3.

With Postfix version 3.2 and later, a non-default directory must be authorized in the default main.cf file, through the alternate_config_di‐ rectories or multi_instance_directories parameters.

With all Postfix versions, you can specify a directory pathname with the MAIL_CONFIG environment variable to override the location of configu‐ ration files.

-F full_name Set the sender full name. This overrides the NAME environment variable, and is used only with messages that have no From: message header.

-f sender Set the envelope sender address. This is the address where delivery problems are sent to. With Postfix versions before 2.1, the Errors-To: message header overrides the error return address.

-G Gateway (relay) submission, as opposed to initial user submission. Either do not rewrite addresses at all, or update incomplete addresses with the domain information specified with remote_header_rewrite_domain.

This option is ignored before Postfix version 2.3.

-h hop_count (ignored) Hop count limit. Use the hopcount_limit configuration parameter instead.

-I Initialize alias database. See the newaliases command above.

-i When reading a message from standard input, don´t treat a line with only a . character as the end of input.

-L label (ignored) The logging label. Use the syslog_name configuration parameter instead.

-m (ignored) Backwards compatibility.

-N dsn (default: 'delay, failure') Delivery status notification control. Specify either a comma-separated list with one or more of failure (send notification when delivery fails), delay (send notification when delivery is delayed), or success (send notification when the message is delivered); or specify never (don't send any notifications at all).

This feature is available in Postfix 2.3 and later.

-n (ignored) Backwards compatibility.

-oAalias_database Non-default alias database. Specify pathname or type:pathname. See postalias(1) for details.

-O option=value (ignored) Set the named option to value. Use the equivalent configuration parameter in main.cf instead.

-o7 (ignored)

-o8 (ignored) To send 8-bit or binary content, use an appropriate MIME encapsulation and specify the appropriate -B command-line option.

-oi When reading a message from standard input, don´t treat a line with only a . character as the end of input.

-om (ignored) The sender is never eliminated from alias etc. expansions.

-o x value (ignored) Set option x to value. Use the equivalent configuration parameter in main.cf instead.

-r sender Set the envelope sender address. This is the address where delivery problems are sent to. With Postfix versions before 2.1, the Errors-To: message header overrides the error return address.

-R return Delivery status notification control. Specify "hdrs" to return only the header when a message bounces, "full" to return a full copy (the de‐ fault behavior).

The -R option specifies an upper bound; Postfix will return only the header, when a full copy would exceed the bounce_size_limit setting.

This option is ignored before Postfix version 2.10.

-q Attempt to deliver all queued mail. This is implemented by executing the postqueue(1) command.

Warning: flushing undeliverable mail frequently will result in poor delivery performance of all other mail.

-qinterval (ignored) The interval between queue runs. Use the queue_run_delay configuration parameter instead.

-qIqueueid Schedule immediate delivery of mail with the specified queue ID. This option is implemented by executing the postqueue(1) command, and is available with Postfix version 2.4 and later.

-qRsite Schedule immediate delivery of all mail that is queued for the named site. This option accepts only site names that are eligible for the "fast flush" service, and is implemented by executing the postqueue(1) command. See flush(8) for more information about the "fast flush" service.

-qSsite This command is not implemented. Use the slower "sendmail -q" command instead.

-t Extract recipients from message headers. These are added to any recipients specified on the command line.

With Postfix versions prior to 2.1, this option requires that no recipient addresses are specified on the command line.

-U (ignored) Initial user submission.

-V envid Specify the envelope ID for notification by servers that support DSN.

This feature is available in Postfix 2.3 and later.

-XV (Postfix 2.2 and earlier: -V) Variable Envelope Return Path. Given an envelope sender address of the form owner-listname@origin, each recipient user@domain receives mail with a personalized envelope sender address.

By default, the personalized envelope sender address is owner-listname+user=domain@origin. The default + and = characters are configurable with the default_verp_delimiters configuration parameter.

-XVxy (Postfix 2.2 and earlier: -Vxy) As -XV, but uses x and y as the VERP delimiter characters, instead of the characters specified with the default_verp_delimiters configuration parameter.

-v Send an email report of the first delivery attempt (Postfix versions 2.1 and later). Mail delivery always happens in the background. When mul‐ tiple -v options are given, enable verbose logging for debugging purposes.

-X log_file (ignored) Log mailer traffic. Use the debug_peer_list and debug_peer_level configuration parameters instead.

Dateien

/var/spool/postfix, mail queue
/etc/postfix, configuration files

ENVIRONMENT

Variable	Beschreibung
MAIL_CONFIG	Directory with Postfix configuration files
MAIL_VERBOSE (value does not matter)	Enable verbose logging for debugging purposes
MAIL_DEBUG (value does not matter)	Enable debugging with an external command, as specified with the debugger_command configuration parameter
NAME	The sender full name. This is used only with messages that have no From: message header. See also the -F option above.

Sicherheit

By design, this program is not set-user (or group) id. It is prepared to handle message content from untrusted, possibly remote, users.

However, like most Postfix programs, this program does not enforce a security policy on its command-line arguments. Instead, it relies on the UNIX system to enforce access policies based on the effective user and group IDs of the process. Concretely, this means that running Postfix commands as root (from sudo or equivalent) on behalf of a non-root user is likely to create privilege escalation opportunities.

If an application runs any Postfix programs on behalf of users that do not have normal shell access to Postfix commands, then that application MUST restrict user-specified command-line arguments to avoid privilege escalation.

• Filter all command-line arguments, for example arguments that contain a pathname or that specify a database access method. These pathname checks must reject user-controlled symlinks or hardlinks to sensitive files, and must not be vulnerable to TOCTOU race attacks.
• Disable command options processing for all command arguments that contain user-specified data. For example, the Postfix sendmail(1) command line MUST be structured as follows:

/path/to/sendmail system-arguments -- user-arguments

Here, the "--" disables command option processing for all user-arguments that follow.

Without the "--", a malicious user could enable Postfix sendmail(1) command options, by specifying an email address that starts with "-".

Dokumentation

Siehe auch

Dienst	Beschreibung
pickup(8)	mail pickup daemon
qmgr(8)	queue manager
smtpd(8)	SMTP server
flush(8)	fast flush service
postsuper(1)	queue maintenance
postalias(1)	create/update/query alias database
postdrop(1)	mail posting utility
postfix(1)	mail system control
postqueue(1)	mail queue control
postlogd(8)	Postfix logging
syslogd(8)	system logging

README_FILES Use "postconf readme_directory" or "postconf html_directory" to locate this information. DEBUG_README, Postfix debugging howto ETRN_README, Postfix ETRN howto VERP_README, Postfix VERP howto

Testfragen

Testfrage 1

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Manpage

newaliases

Initialize the alias database. If no input file is specified (with the -oA option, see below), the program processes the file(s) specified with the alias_database configuration parameter. If no alias database type is specified, the program uses the type specified with the default_database_type configuration parameter. This mode of operation is implemented by running the postalias(1) command.

Note
it may take a minute or so before an alias database update becomes visible. Use the "postfix reload" command to eliminate this delay.

These and other features can be selected by specifying the appropriate combination of command-line options. Some features are controlled by parameters in the main.cf configuration file.

DIAGNOSTICS

Problems are logged to syslogd(8) or postlogd(8), and to the standard error stream.