Adding upstream version 3.8.5.upstream/3.8.5

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1397 insertions, 0 deletions

diff --git a/src/pipe/pipe.c b/src/pipe/pipe.c
new file mode 100644
index 0000000..8a99430
--- /dev/null
+++ b/src/pipe/pipe.c
@@ -0,0 +1,1397 @@
+/*++
+/* NAME
+/*	pipe 8
+/* SUMMARY
+/*	Postfix delivery to external command
+/* SYNOPSIS
+/*	\fBpipe\fR [generic Postfix daemon options] command_attributes...
+/* DESCRIPTION
+/*	The \fBpipe\fR(8) daemon processes requests from the Postfix queue
+/*	manager to deliver messages to external commands.
+/*	This program expects to be run from the \fBmaster\fR(8) process
+/*	manager.
+/*
+/*	Message attributes such as sender address, recipient address and
+/*	next-hop host name can be specified as command-line macros that are
+/*	expanded before the external command is executed.
+/*
+/*	The \fBpipe\fR(8) daemon updates queue files and marks recipients
+/*	as finished, or it informs the queue manager that delivery should
+/*	be tried again at a later time. Delivery status reports are sent
+/*	to the \fBbounce\fR(8), \fBdefer\fR(8) or \fBtrace\fR(8) daemon as
+/*	appropriate.
+/* SINGLE-RECIPIENT DELIVERY
+/* .ad
+/* .fi
+/*	Some destinations cannot handle more than one recipient per
+/*	delivery request. Examples are pagers or fax machines.
+/*	In addition, multi-recipient delivery is undesirable when
+/*	prepending a \fBDelivered-to:\fR or \fBX-Original-To:\fR
+/*	message header.
+/*
+/*	To prevent Postfix from sending multiple recipients per delivery
+/*	request, specify
+/* .sp
+/* .nf
+/*	    \fItransport\fB_destination_recipient_limit = 1\fR
+/* .fi
+/*
+/*	in the Postfix \fBmain.cf\fR file, where \fItransport\fR
+/*	is the name in the first column of the Postfix \fBmaster.cf\fR
+/*	entry for the pipe-based delivery transport.
+/* COMMAND ATTRIBUTE SYNTAX
+/* .ad
+/* .fi
+/*	The external command attributes are given in the \fBmaster.cf\fR
+/*	file at the end of a service definition.  The syntax is as follows:
+/* .IP "\fBchroot=\fIpathname\fR (optional)"
+/*	Change the process root directory and working directory to
+/*	the named directory. This happens before switching to the
+/*	privileges specified with the \fBuser\fR attribute, and
+/*	before executing the optional \fBdirectory=\fIpathname\fR
+/*	directive. Delivery is deferred in case of failure.
+/* .sp
+/*	This feature is available as of Postfix 2.3.
+/* .IP "\fBdirectory=\fIpathname\fR (optional)"
+/*	Change to the named directory before executing the external command.
+/*	The directory must be accessible for the user specified with the
+/*	\fBuser\fR attribute (see below).
+/*	The default working directory is \fB$queue_directory\fR.
+/*	Delivery is deferred in case of failure.
+/* .sp
+/*	This feature is available as of Postfix 2.2.
+/* .IP "\fBeol=\fIstring\fR (optional, default: \fB\en\fR)"
+/*	The output record delimiter. Typically one would use either
+/*	\fB\er\en\fR or \fB\en\fR. The usual C-style backslash escape
+/*	sequences are recognized: \fB\ea \eb \ef \en \er \et \ev
+/*	\e\fIddd\fR (up to three octal digits) and \fB\e\e\fR.
+/* .IP "\fBflags=BDFORXhqu.>\fR (optional)"
+/*	Optional message processing flags. By default, a message is
+/*	copied unchanged.
+/* .RS
+/* .IP \fBB\fR
+/*	Append a blank line at the end of each message. This is required
+/*	by some mail user agents that recognize "\fBFrom \fR" lines only
+/*	when preceded by a blank line.
+/* .IP \fBD\fR
+/*	Prepend a "\fBDelivered-To: \fIrecipient\fR" message header with the
+/*	envelope recipient address. Note: for this to work, the
+/*	\fItransport\fB_destination_recipient_limit\fR must be 1
+/*	(see SINGLE-RECIPIENT DELIVERY above for details).
+/* .sp
+/*	The \fBD\fR flag also enforces loop detection (Postfix 2.5 and later):
+/*	if a message already contains a \fBDelivered-To:\fR header
+/*	with the same recipient address, then the message is
+/*	returned as undeliverable. The address comparison is case
+/*	insensitive.
+/* .sp
+/*	This feature is available as of Postfix 2.0.
+/* .IP \fBF\fR
+/*	Prepend a "\fBFrom \fIsender time_stamp\fR" envelope header to
+/*	the message content.
+/*	This is expected by, for example, \fBUUCP\fR software.
+/* .IP \fBO\fR
+/*	Prepend an "\fBX-Original-To: \fIrecipient\fR" message header
+/*	with the recipient address as given to Postfix. Note: for this to
+/*	work, the \fItransport\fB_destination_recipient_limit\fR must be 1
+/*	(see SINGLE-RECIPIENT DELIVERY above for details).
+/* .sp
+/*	This feature is available as of Postfix 2.0.
+/* .IP \fBR\fR
+/*	Prepend a \fBReturn-Path:\fR message header with the envelope sender
+/*	address.
+/* .IP \fBX\fR
+/*	Indicate that the external command performs final delivery.
+/*	This flag affects the status reported in "success" DSN
+/*	(delivery status notification) messages, and changes it
+/*	from "relayed" into "delivered".
+/* .sp
+/*	This feature is available as of Postfix 2.5.
+/* .IP \fBh\fR
+/*	Fold the command-line \fB$original_recipient\fR and
+/*	\fB$recipient\fR address domain part
+/*	(text to the right of the right-most \fB@\fR character) to
+/*	lower case; fold the entire command-line \fB$domain\fR and
+/*	\fB$nexthop\fR host or domain information to lower case.
+/*	This is recommended for delivery via \fBUUCP\fR.
+/* .IP \fBq\fR
+/*	Quote white space and other special characters in the command-line
+/*	\fB$sender\fR, \fB$original_recipient\fR and \fB$recipient\fR
+/*	address localparts (text to the
+/*	left of the right-most \fB@\fR character), according to an 8-bit
+/*	transparent version of RFC 822.
+/*	This is recommended for delivery via \fBUUCP\fR or \fBBSMTP\fR.
+/* .sp
+/*	The result is compatible with the address parsing of command-line
+/*	recipients by the Postfix \fBsendmail\fR(1) mail submission command.
+/* .sp
+/*	The \fBq\fR flag affects only entire addresses, not the partial
+/*	address information from the \fB$user\fR, \fB$extension\fR or
+/*	\fB$mailbox\fR command-line macros.
+/* .IP \fBu\fR
+/*	Fold the command-line \fB$original_recipient\fR and
+/*	\fB$recipient\fR address localpart (text to
+/*	the left of the right-most \fB@\fR character) to lower case.
+/*	This is recommended for delivery via \fBUUCP\fR.
+/* .IP \fB.\fR
+/*	Prepend "\fB.\fR" to lines starting with "\fB.\fR". This is needed
+/*	by, for example, \fBBSMTP\fR software.
+/* .IP \fB>\fR
+/*	Prepend "\fB>\fR" to lines starting with "\fBFrom \fR". This is expected
+/*	by, for example, \fBUUCP\fR software.
+/* .RE
+/* .IP "\fBnull_sender\fR=\fIreplacement\fR (default: MAILER-DAEMON)"
+/*	Replace the null sender address (typically used for delivery
+/*	status notifications) with the specified text
+/*	when expanding the \fB$sender\fR command-line macro, and
+/*	when generating a From_ or Return-Path: message header.
+/*
+/*	If the null sender replacement text is a non-empty string
+/*	then it is affected by the \fBq\fR flag for address quoting
+/*	in command-line arguments.
+/*
+/*	The null sender replacement text may be empty; this form
+/*	is recommended for content filters that feed mail back into
+/*	Postfix. The empty sender address is not affected by the
+/*	\fBq\fR flag for address quoting in command-line arguments.
+/* .sp
+/*	Caution: a null sender address is easily mis-parsed by
+/*	naive software. For example, when the \fBpipe\fR(8) daemon
+/*	executes a command such as:
+/* .sp
+/* .nf
+/*	    \fIWrong\fR: command -f$sender -- $recipient
+/* .fi
+/* .IP
+/*	the command will mis-parse the -f option value when the
+/*	sender address is a null string.  For correct parsing,
+/*	specify \fB$sender\fR as an argument by itself:
+/* .sp
+/* .nf
+/*	    \fIRight\fR: command -f $sender -- $recipient
+/* .fi
+/* NOTE: DO NOT put quotes around the command, $sender, or $recipient.
+/* .IP
+/*	This feature is available as of Postfix 2.3.
+/* .IP "\fBsize\fR=\fIsize_limit\fR (optional)"
+/*	Don't deliver messages that exceed this size limit (in
+/*	bytes); return them to the sender instead.
+/* .IP "\fBuser\fR=\fIusername\fR (required)"
+/* .IP "\fBuser\fR=\fIusername\fR:\fIgroupname\fR"
+/*	Execute the external command with the user ID and group ID of the
+/*	specified \fIusername\fR.  The software refuses to execute
+/*	commands with root privileges, or with the privileges of the
+/*	mail system owner. If \fIgroupname\fR is specified, the
+/*	corresponding group ID is used instead of the group ID of
+/*	\fIusername\fR.
+/* .IP "\fBargv\fR=\fIcommand\fR... (required)"
+/*	The command to be executed. This must be specified as the
+/*	last command attribute.
+/*	The command is executed directly, i.e. without interpretation of
+/*	shell meta characters by a shell command interpreter.
+/* .sp
+/*	Specify "{" and "}" around command arguments that contain
+/*	whitespace (Postfix 3.0 and later). Whitespace
+/*	after the opening "{" and before the closing "}" is ignored.
+/* .sp
+/*	In the command argument vector, the following macros are recognized
+/*	and replaced with corresponding information from the Postfix queue
+/*	manager delivery request.
+/* .sp
+/*	In addition to the form ${\fIname\fR}, the forms $\fIname\fR and
+/*	the deprecated form $(\fIname\fR) are also recognized.
+/*	Specify \fB$$\fR where a single \fB$\fR is wanted.
+/* .RS
+/* .IP \fB${client_address}\fR
+/*	This macro expands to the remote client network address.
+/* .sp
+/*	This feature is available as of Postfix 2.2.
+/* .IP \fB${client_helo}\fR
+/*	This macro expands to the remote client HELO command parameter.
+/* .sp
+/*	This feature is available as of Postfix 2.2.
+/* .IP \fB${client_hostname}\fR
+/*	This macro expands to the remote client hostname.
+/* .sp
+/*	This feature is available as of Postfix 2.2.
+/* .IP \fB${client_port}\fR
+/*	This macro expands to the remote client TCP port number.
+/* .sp
+/*	This feature is available as of Postfix 2.5.
+/* .IP \fB${client_protocol}\fR
+/*	This macro expands to the remote client protocol.
+/* .sp
+/*	This feature is available as of Postfix 2.2.
+/* .IP \fB${domain}\fR
+/*	This macro expands to the domain portion of the recipient
+/*	address.  For example, with an address \fIuser+foo@domain\fR
+/*	the domain is \fIdomain\fR.
+/* .sp
+/*	This information is modified by the \fBh\fR flag for case folding.
+/* .sp
+/*	This feature is available as of Postfix 2.5.
+/* .IP \fB${extension}\fR
+/*	This macro expands to the extension part of a recipient address.
+/*	For example, with an address \fIuser+foo@domain\fR the extension is
+/*	\fIfoo\fR.
+/* .sp
+/*	A command-line argument that contains \fB${extension}\fR expands
+/*	into as many command-line arguments as there are recipients.
+/* .sp
+/*	This information is modified by the \fBu\fR flag for case folding.
+/* .IP \fB${mailbox}\fR
+/*	This macro expands to the complete local part of a recipient address.
+/*	For example, with an address \fIuser+foo@domain\fR the mailbox is
+/*	\fIuser+foo\fR.
+/* .sp
+/*	A command-line argument that contains \fB${mailbox}\fR
+/*	expands to as many command-line arguments as there are recipients.
+/* .sp
+/*	This information is modified by the \fBu\fR flag for case folding.
+/* .IP \fB${nexthop}\fR
+/*	This macro expands to the next-hop hostname.
+/* .sp
+/*	This information is modified by the \fBh\fR flag for case folding.
+/* .IP \fB${original_recipient}\fR
+/*	This macro expands to the complete recipient address before any
+/*	address rewriting or aliasing.
+/* .sp
+/*	A command-line argument that contains
+/*	\fB${original_recipient}\fR expands to as many
+/*	command-line arguments as there are recipients.
+/* .sp
+/*	This information is modified by the \fBhqu\fR flags for quoting
+/*	and case folding.
+/* .sp
+/*	This feature is available as of Postfix 2.5.
+/* .IP \fB${queue_id}\fR
+/*	This macro expands to the queue id.
+/* .sp
+/*	This feature is available as of Postfix 2.11.
+/* .IP \fB${recipient}\fR
+/*	This macro expands to the complete recipient address.
+/* .sp
+/*	A command-line argument that contains \fB${recipient}\fR
+/*	expands to as many command-line arguments as there are recipients.
+/* .sp
+/*	This information is modified by the \fBhqu\fR flags for quoting
+/*	and case folding.
+/* .IP \fB${sasl_method}\fR
+/*	This macro expands to the name of the SASL authentication
+/*	mechanism in the AUTH command when the Postfix SMTP server
+/*	received the message.
+/* .sp
+/*	This feature is available as of Postfix 2.2.
+/* .IP \fB${sasl_sender}\fR
+/*	This macro expands to the SASL sender name (i.e. the original
+/*	submitter as per RFC 4954) in the MAIL FROM command when
+/*	the Postfix SMTP server received the message.
+/* .sp
+/*	This feature is available as of Postfix 2.2.
+/* .IP \fB${sasl_username}\fR
+/*	This macro expands to the SASL user name in the AUTH command
+/*	when the Postfix SMTP server received the message.
+/* .sp
+/*	This feature is available as of Postfix 2.2.
+/* .IP \fB${sender}\fR
+/*	This macro expands to the envelope sender address. By default,
+/*	the null sender address expands to MAILER-DAEMON; this can
+/*	be changed with the \fBnull_sender\fR attribute, as described
+/*	above.
+/* .sp
+/*	This information is modified by the \fBq\fR flag for quoting.
+/* .IP \fB${size}\fR
+/*	This macro expands to Postfix's idea of the message size, which
+/*	is an approximation of the size of the message as delivered.
+/* .IP \fB${user}\fR
+/*	This macro expands to the username part of a recipient address.
+/*	For example, with an address \fIuser+foo@domain\fR the username
+/*	part is \fIuser\fR.
+/* .sp
+/*	A command-line argument that contains \fB${user}\fR expands
+/*	into as many command-line arguments as there are recipients.
+/* .sp
+/*	This information is modified by the \fBu\fR flag for case folding.
+/* .RE
+/* STANDARDS
+/*	RFC 3463 (Enhanced status codes)
+/* DIAGNOSTICS
+/*	Command exit status codes are expected to
+/*	follow the conventions defined in <\fBsysexits.h\fR>.
+/*	Exit status 0 means normal successful completion.
+/*
+/*	In the case of a non-zero exit status, a limited amount of
+/*	command output is logged, and reported in a delivery status
+/*	notification.  When the output begins with a 4.X.X or 5.X.X
+/*	enhanced status code, the status code takes precedence over
+/*	the non-zero exit status (Postfix version 2.3 and later).
+/*
+/*	After successful delivery (zero exit status) a limited
+/*	amount of command output is logged, and reported in "success"
+/*	delivery status notifications (Postfix 3.0 and later).
+/*	This command output is not examined for the presence of an
+/*	enhanced status code.
+/*
+/*	Problems and transactions are logged to \fBsyslogd\fR(8)
+/*	or \fBpostlogd\fR(8).
+/*	Corrupted message files are marked so that the queue manager
+/*	can move them to the \fBcorrupt\fR queue for further inspection.
+/* SECURITY
+/* .fi
+/* .ad
+/*	This program needs a dual personality 1) to access the private
+/*	Postfix queue and IPC mechanisms, and 2) to execute external
+/*	commands as the specified user. It is therefore security sensitive.
+/* CONFIGURATION PARAMETERS
+/* .ad
+/* .fi
+/*	Changes to \fBmain.cf\fR are picked up automatically as \fBpipe\fR(8)
+/*	processes run for only a limited amount of time. Use the command
+/*	"\fBpostfix reload\fR" to speed up a change.
+/*
+/*	The text below provides only a parameter summary. See
+/*	\fBpostconf\fR(5) for more details including examples.
+/* RESOURCE AND RATE CONTROLS
+/* .ad
+/* .fi
+/*	In the text below, \fItransport\fR is the first field in a
+/*	\fBmaster.cf\fR entry.
+/* .IP "\fBtransport_time_limit ($command_time_limit)\fR"
+/*	A transport-specific override for the command_time_limit parameter
+/*	value, where \fItransport\fR is the master.cf name of the message
+/*	delivery transport.
+/* .PP
+/*	Implemented in the qmgr(8) daemon:
+/* .IP "\fBtransport_destination_concurrency_limit ($default_destination_concurrency_limit)\fR"
+/*	A transport-specific override for the
+/*	default_destination_concurrency_limit parameter value, where
+/*	\fItransport\fR is the master.cf name of the message delivery
+/*	transport.
+/* .IP "\fBtransport_destination_recipient_limit ($default_destination_recipient_limit)\fR"
+/*	A transport-specific override for the
+/*	default_destination_recipient_limit parameter value, where
+/*	\fItransport\fR is the master.cf name of the message delivery
+/*	transport.
+/* MISCELLANEOUS CONTROLS
+/* .ad
+/* .fi
+/* .IP "\fBconfig_directory (see 'postconf -d' output)\fR"
+/*	The default location of the Postfix main.cf and master.cf
+/*	configuration files.
+/* .IP "\fBdaemon_timeout (18000s)\fR"
+/*	How much time a Postfix daemon process may take to handle a
+/*	request before it is terminated by a built-in watchdog timer.
+/* .IP "\fBdelay_logging_resolution_limit (2)\fR"
+/*	The maximal number of digits after the decimal point when logging
+/*	sub-second delay values.
+/* .IP "\fBexport_environment (see 'postconf -d' output)\fR"
+/*	The list of environment variables that a Postfix process will export
+/*	to non-Postfix processes.
+/* .IP "\fBipc_timeout (3600s)\fR"
+/*	The time limit for sending or receiving information over an internal
+/*	communication channel.
+/* .IP "\fBmail_owner (postfix)\fR"
+/*	The UNIX system account that owns the Postfix queue and most Postfix
+/*	daemon processes.
+/* .IP "\fBmax_idle (100s)\fR"
+/*	The maximum amount of time that an idle Postfix daemon process waits
+/*	for an incoming connection before terminating voluntarily.
+/* .IP "\fBmax_use (100)\fR"
+/*	The maximal number of incoming connections that a Postfix daemon
+/*	process will service before terminating voluntarily.
+/* .IP "\fBprocess_id (read-only)\fR"
+/*	The process ID of a Postfix command or daemon process.
+/* .IP "\fBprocess_name (read-only)\fR"
+/*	The process name of a Postfix command or daemon process.
+/* .IP "\fBqueue_directory (see 'postconf -d' output)\fR"
+/*	The location of the Postfix top-level queue directory.
+/* .IP "\fBrecipient_delimiter (empty)\fR"
+/*	The set of characters that can separate an email address
+/*	localpart, user name, or a .forward file name from its extension.
+/* .IP "\fBsyslog_facility (mail)\fR"
+/*	The syslog facility of Postfix logging.
+/* .IP "\fBsyslog_name (see 'postconf -d' output)\fR"
+/*	A prefix that is prepended to the process name in syslog
+/*	records, so that, for example, "smtpd" becomes "prefix/smtpd".
+/* .PP
+/*	Available in Postfix version 3.0 and later:
+/* .IP "\fBpipe_delivery_status_filter ($default_delivery_status_filter)\fR"
+/*	Optional filter for the \fBpipe\fR(8) delivery agent to change the
+/*	delivery status code or explanatory text of successful or unsuccessful
+/*	deliveries.
+/* .PP
+/*	Available in Postfix version 3.3 and later:
+/* .IP "\fBenable_original_recipient (yes)\fR"
+/*	Enable support for the original recipient address after an
+/*	address is rewritten to a different address (for example with
+/*	aliasing or with canonical mapping).
+/* .IP "\fBservice_name (read-only)\fR"
+/*	The master.cf service name of a Postfix daemon process.
+/* .PP
+/*	Available in Postfix 3.5 and later:
+/* .IP "\fBinfo_log_address_format (external)\fR"
+/*	The email address form that will be used in non-debug logging
+/*	(info, warning, etc.).
+/* SEE ALSO
+/*	qmgr(8), queue manager
+/*	bounce(8), delivery status reports
+/*	postconf(5), configuration parameters
+/*	master(5), generic daemon options
+/*	master(8), process manager
+/*	postlogd(8), Postfix logging
+/*	syslogd(8), system logging
+/* LICENSE
+/* .ad
+/* .fi
+/*	The Secure Mailer license must be distributed with this software.
+/* AUTHOR(S)
+/*	Wietse Venema
+/*	IBM T.J. Watson Research
+/*	P.O. Box 704
+/*	Yorktown Heights, NY 10598, USA
+/*
+/*	Wietse Venema
+/*	Google, Inc.
+/*	111 8th Avenue
+/*	New York, NY 10011, USA
+/*--*/
+
+/* System library. */
+
+#include <sys_defs.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <pwd.h>
+#include <grp.h>
+#include <fcntl.h>
+#include <ctype.h>
+
+#ifdef STRCASECMP_IN_STRINGS_H
+#include <strings.h>
+#endif
+
+/* Utility library. */
+
+#include <msg.h>
+#include <vstream.h>
+#include <vstring.h>
+#include <argv.h>
+#include <htable.h>
+#include <dict.h>
+#include <iostuff.h>
+#include <mymalloc.h>
+#include <mac_parse.h>
+#include <set_eugid.h>
+#include <split_at.h>
+#include <stringops.h>
+
+/* Global library. */
+
+#include <recipient_list.h>
+#include <deliver_request.h>
+#include <mail_params.h>
+#include <mail_version.h>
+#include <mail_conf.h>
+#include <bounce.h>
+#include <defer.h>
+#include <deliver_completed.h>
+#include <sent.h>
+#include <pipe_command.h>
+#include <mail_copy.h>
+#include <mail_addr.h>
+#include <canon_addr.h>
+#include <split_addr.h>
+#include <off_cvt.h>
+#include <quote_822_local.h>
+#include <flush_clnt.h>
+#include <dsn_util.h>
+#include <dsn_buf.h>
+#include <sys_exits.h>
+#include <delivered_hdr.h>
+#include <fold_addr.h>
+#include <mail_parm_split.h>
+
+/* Single server skeleton. */
+
+#include <mail_server.h>
+
+/* Application-specific. */
+
+ /*
+  * The mini symbol table name and keys used for expanding macros in
+  * command-line arguments.
+  * 
+  * XXX Update  the parse_callback() routine when something gets added here,
+  * even when the macro is not recipient dependent.
+  */
+#define PIPE_DICT_TABLE		"pipe_command"	/* table name */
+#define PIPE_DICT_NEXTHOP	"nexthop"	/* key */
+#define PIPE_DICT_RCPT		"recipient"	/* key */
+#define PIPE_DICT_ORIG_RCPT	"original_recipient"	/* key */
+#define PIPE_DICT_SENDER	"sender"/* key */
+#define PIPE_DICT_USER		"user"	/* key */
+#define PIPE_DICT_EXTENSION	"extension"	/* key */
+#define PIPE_DICT_MAILBOX	"mailbox"	/* key */
+#define PIPE_DICT_DOMAIN	"domain"/* key */
+#define PIPE_DICT_SIZE		"size"	/* key */
+#define PIPE_DICT_CLIENT_ADDR	"client_address"	/* key */
+#define PIPE_DICT_CLIENT_NAME	"client_hostname"	/* key */
+#define PIPE_DICT_CLIENT_PORT	"client_port"	/* key */
+#define PIPE_DICT_CLIENT_PROTO	"client_protocol"	/* key */
+#define PIPE_DICT_CLIENT_HELO	"client_helo"	/* key */
+#define PIPE_DICT_SASL_METHOD	"sasl_method"	/* key */
+#define PIPE_DICT_SASL_USERNAME	"sasl_username"	/* key */
+#define PIPE_DICT_SASL_SENDER	"sasl_sender"	/* key */
+#define PIPE_DICT_QUEUE_ID	"queue_id"	/* key */
+
+ /*
+  * Flags used to pass back the type of special parameter found by
+  * parse_callback.
+  */
+#define PIPE_FLAG_RCPT		(1<<0)
+#define PIPE_FLAG_USER		(1<<1)
+#define PIPE_FLAG_EXTENSION	(1<<2)
+#define PIPE_FLAG_MAILBOX	(1<<3)
+#define PIPE_FLAG_DOMAIN	(1<<4)
+#define PIPE_FLAG_ORIG_RCPT	(1<<5)
+
+ /*
+  * Additional flags. These are colocated with mail_copy() flags. Allow some
+  * space for extension of the mail_copy() interface.
+  */
+#define PIPE_OPT_FOLD_BASE	(16)
+#define PIPE_OPT_FOLD_USER	(FOLD_ADDR_USER << PIPE_OPT_FOLD_BASE)
+#define PIPE_OPT_FOLD_HOST	(FOLD_ADDR_HOST << PIPE_OPT_FOLD_BASE)
+#define PIPE_OPT_QUOTE_LOCAL	(1 << (PIPE_OPT_FOLD_BASE + 2))
+#define PIPE_OPT_FINAL_DELIVERY	(1 << (PIPE_OPT_FOLD_BASE + 3))
+
+#define PIPE_OPT_FOLD_ALL	(FOLD_ADDR_ALL << PIPE_OPT_FOLD_BASE)
+#define PIPE_OPT_FOLD_FLAGS(f) \
+	(((f) & PIPE_OPT_FOLD_ALL) >> PIPE_OPT_FOLD_BASE)
+
+ /*
+  * Tunable parameters. Values are taken from the config file, after
+  * prepending the service name to _name, and so on.
+  */
+int     var_command_maxtime;		/* You can now leave this here. */
+
+ /*
+  * Other main.cf parameters.
+  */
+char   *var_pipe_dsn_filter;
+
+ /*
+  * For convenience. Instead of passing around lists of parameters, bundle
+  * them up in convenient structures.
+  */
+
+ /*
+  * Structure for service-specific configuration parameters.
+  */
+typedef struct {
+    int     time_limit;			/* per-service time limit */
+} PIPE_PARAMS;
+
+ /*
+  * Structure for command-line parameters.
+  */
+typedef struct {
+    char  **command;			/* argument vector */
+    uid_t   uid;			/* command privileges */
+    gid_t   gid;			/* command privileges */
+    int     flags;			/* mail_copy() flags */
+    char   *exec_dir;			/* working directory */
+    char   *chroot_dir;			/* chroot directory */
+    VSTRING *eol;			/* output record delimiter */
+    VSTRING *null_sender;		/* null sender expansion */
+    off_t   size_limit;			/* max size in bytes we will accept */
+} PIPE_ATTR;
+
+ /*
+  * Structure for command-line parameter macro expansion.
+  */
+typedef struct {
+    const char *service;		/* for warnings */
+    int     expand_flag;		/* callback result */
+} PIPE_STATE;
+
+ /*
+  * Silly little macros.
+  */
+#define STR	vstring_str
+
+/* parse_callback - callback for mac_parse() */
+
+static int parse_callback(int type, VSTRING *buf, void *context)
+{
+    PIPE_STATE *state = (PIPE_STATE *) context;
+    struct cmd_flags {
+	const char *name;
+	int     flags;
+    };
+    static struct cmd_flags cmd_flags[] = {
+	PIPE_DICT_NEXTHOP, 0,
+	PIPE_DICT_RCPT, PIPE_FLAG_RCPT,
+	PIPE_DICT_ORIG_RCPT, PIPE_FLAG_ORIG_RCPT,
+	PIPE_DICT_SENDER, 0,
+	PIPE_DICT_USER, PIPE_FLAG_USER,
+	PIPE_DICT_EXTENSION, PIPE_FLAG_EXTENSION,
+	PIPE_DICT_MAILBOX, PIPE_FLAG_MAILBOX,
+	PIPE_DICT_DOMAIN, PIPE_FLAG_DOMAIN,
+	PIPE_DICT_SIZE, 0,
+	PIPE_DICT_CLIENT_ADDR, 0,
+	PIPE_DICT_CLIENT_NAME, 0,
+	PIPE_DICT_CLIENT_PORT, 0,
+	PIPE_DICT_CLIENT_PROTO, 0,
+	PIPE_DICT_CLIENT_HELO, 0,
+	PIPE_DICT_SASL_METHOD, 0,
+	PIPE_DICT_SASL_USERNAME, 0,
+	PIPE_DICT_SASL_SENDER, 0,
+	PIPE_DICT_QUEUE_ID, 0,
+	0, 0,
+    };
+    struct cmd_flags *p;
+
+    /*
+     * See if this command-line argument references a special macro.
+     */
+    if (type == MAC_PARSE_VARNAME) {
+	for (p = cmd_flags; /* see below */ ; p++) {
+	    if (p->name == 0) {
+		msg_warn("file %s/%s: service %s: unknown macro name: \"%s\"",
+			 var_config_dir, MASTER_CONF_FILE,
+			 state->service, vstring_str(buf));
+		return (MAC_PARSE_ERROR);
+	    } else if (strcmp(vstring_str(buf), p->name) == 0) {
+		state->expand_flag |= p->flags;
+		return (0);
+	    }
+	}
+    }
+    return (0);
+}
+
+/* morph_recipient - morph a recipient address */
+
+static void morph_recipient(VSTRING *buf, const char *address, int flags)
+{
+    VSTRING *temp = vstring_alloc(100);
+
+    /*
+     * Quote the recipient address as appropriate.
+     */
+    if (flags & PIPE_OPT_QUOTE_LOCAL)
+	quote_822_local(temp, address);
+    else
+	vstring_strcpy(temp, address);
+
+    /*
+     * Fold the recipient address as appropriate.
+     */
+    fold_addr(buf, STR(temp), PIPE_OPT_FOLD_FLAGS(flags));
+
+    vstring_free(temp);
+}
+
+/* expand_argv - expand macros in the argument vector */
+
+static ARGV *expand_argv(const char *service, char **argv,
+			         RECIPIENT_LIST *rcpt_list, int flags)
+{
+    VSTRING *buf = vstring_alloc(100);
+    ARGV   *result;
+    char  **cpp;
+    PIPE_STATE state;
+    int     i;
+    char   *ext;
+    char   *dom;
+
+    /*
+     * This appears to be simple operation (replace $name by its expansion).
+     * However, it becomes complex because a command-line argument that
+     * references $recipient must expand to as many command-line arguments as
+     * there are recipients (that's wat programs called by sendmail expect).
+     * So we parse each command-line argument, and depending on what we find,
+     * we either expand the argument just once, or we expand it once for each
+     * recipient. In either case we end up parsing the command-line argument
+     * twice. The amount of CPU time wasted will be negligible.
+     * 
+     * Note: we can't use recursive macro expansion here, because recursion
+     * would screw up mail addresses that contain $ characters.
+     */
+#define NO	0
+#define EARLY_RETURN(x) { argv_free(result); vstring_free(buf); return (x); }
+
+    result = argv_alloc(1);
+    for (cpp = argv; *cpp; cpp++) {
+	state.service = service;
+	state.expand_flag = 0;
+	if (mac_parse(*cpp, parse_callback, (void *) &state) & MAC_PARSE_ERROR)
+	    EARLY_RETURN(0);
+	if (state.expand_flag == 0) {		/* no $recipient etc. */
+	    argv_add(result, dict_eval(PIPE_DICT_TABLE, *cpp, NO), ARGV_END);
+	} else {				/* contains $recipient etc. */
+	    for (i = 0; i < rcpt_list->len; i++) {
+
+		/*
+		 * This argument contains $recipient.
+		 */
+		if (state.expand_flag & PIPE_FLAG_RCPT) {
+		    morph_recipient(buf, rcpt_list->info[i].address, flags);
+		    dict_update(PIPE_DICT_TABLE, PIPE_DICT_RCPT, STR(buf));
+		}
+
+		/*
+		 * This argument contains $original_recipient.
+		 */
+		if (state.expand_flag & PIPE_FLAG_ORIG_RCPT) {
+		    morph_recipient(buf, rcpt_list->info[i].orig_addr, flags);
+		    dict_update(PIPE_DICT_TABLE, PIPE_DICT_ORIG_RCPT, STR(buf));
+		}
+
+		/*
+		 * This argument contains $user. Extract the plain user name.
+		 * Either anything to the left of the extension delimiter or,
+		 * in absence of the latter, anything to the left of the
+		 * rightmost @.
+		 * 
+		 * Beware: if the user name is blank (e.g. +user@host), the
+		 * argument is suppressed. This is necessary to allow for
+		 * cyrus bulletin-board (global mailbox) delivery. XXX But,
+		 * skipping empty user parts will also prevent other
+		 * expansions of this specific command-line argument.
+		 */
+		if (state.expand_flag & PIPE_FLAG_USER) {
+		    morph_recipient(buf, rcpt_list->info[i].address,
+				    flags & PIPE_OPT_FOLD_ALL);
+		    if (split_at_right(STR(buf), '@') == 0)
+			msg_warn("no @ in recipient address: %s",
+				 rcpt_list->info[i].address);
+		    if (*var_rcpt_delim)
+			split_addr(STR(buf), var_rcpt_delim);
+		    if (*STR(buf) == 0)
+			continue;
+		    dict_update(PIPE_DICT_TABLE, PIPE_DICT_USER, STR(buf));
+		}
+
+		/*
+		 * This argument contains $extension. Extract the recipient
+		 * extension: anything between the leftmost extension
+		 * delimiter and the rightmost @. The extension may be blank.
+		 */
+		if (state.expand_flag & PIPE_FLAG_EXTENSION) {
+		    morph_recipient(buf, rcpt_list->info[i].address,
+				    flags & PIPE_OPT_FOLD_ALL);
+		    if (split_at_right(STR(buf), '@') == 0)
+			msg_warn("no @ in recipient address: %s",
+				 rcpt_list->info[i].address);
+		    if (*var_rcpt_delim == 0
+			|| (ext = split_addr(STR(buf), var_rcpt_delim)) == 0)
+			ext = "";		/* insert null arg */
+		    dict_update(PIPE_DICT_TABLE, PIPE_DICT_EXTENSION, ext);
+		}
+
+		/*
+		 * This argument contains $mailbox. Extract the mailbox name:
+		 * anything to the left of the rightmost @.
+		 */
+		if (state.expand_flag & PIPE_FLAG_MAILBOX) {
+		    morph_recipient(buf, rcpt_list->info[i].address,
+				    flags & PIPE_OPT_FOLD_ALL);
+		    if (split_at_right(STR(buf), '@') == 0)
+			msg_warn("no @ in recipient address: %s",
+				 rcpt_list->info[i].address);
+		    dict_update(PIPE_DICT_TABLE, PIPE_DICT_MAILBOX, STR(buf));
+		}
+
+		/*
+		 * This argument contains $domain. Extract the domain name:
+		 * anything to the right of the rightmost @.
+		 */
+		if (state.expand_flag & PIPE_FLAG_DOMAIN) {
+		    morph_recipient(buf, rcpt_list->info[i].address,
+				    flags & PIPE_OPT_FOLD_ALL);
+		    dom = split_at_right(STR(buf), '@');
+		    if (dom == 0) {
+			msg_warn("no @ in recipient address: %s",
+				 rcpt_list->info[i].address);
+			dom = "";		/* insert null arg */
+		    }
+		    dict_update(PIPE_DICT_TABLE, PIPE_DICT_DOMAIN, dom);
+		}
+
+		/*
+		 * Done.
+		 */
+		argv_add(result, dict_eval(PIPE_DICT_TABLE, *cpp, NO), ARGV_END);
+	    }
+	}
+    }
+    argv_terminate(result);
+    vstring_free(buf);
+    return (result);
+}
+
+/* get_service_params - get service-name dependent config information */
+
+static void get_service_params(PIPE_PARAMS *config, char *service)
+{
+    const char *myname = "get_service_params";
+
+    /*
+     * Figure out the command time limit for this transport.
+     */
+    config->time_limit =
+	get_mail_conf_time2(service, _MAXTIME, var_command_maxtime, 's', 1, 0);
+
+    /*
+     * Give the poor tester a clue of what is going on.
+     */
+    if (msg_verbose)
+	msg_info("%s: time_limit %d", myname, config->time_limit);
+}
+
+/* get_service_attr - get command-line attributes */
+
+static void get_service_attr(PIPE_ATTR *attr, char **argv)
+{
+    const char *myname = "get_service_attr";
+    struct passwd *pwd;
+    struct group *grp;
+    char   *user;			/* user name */
+    char   *group;			/* group name */
+    char   *size;			/* max message size */
+    char   *cp;
+
+    /*
+     * Initialize.
+     */
+    user = 0;
+    group = 0;
+    attr->command = 0;
+    attr->flags = 0;
+    attr->exec_dir = 0;
+    attr->chroot_dir = 0;
+    attr->eol = vstring_strcpy(vstring_alloc(1), "\n");
+    attr->null_sender = vstring_strcpy(vstring_alloc(1), MAIL_ADDR_MAIL_DAEMON);
+    attr->size_limit = 0;
+
+    /*
+     * Iterate over the command-line attribute list.
+     */
+    for ( /* void */ ; *argv != 0; argv++) {
+
+	/*
+	 * flags=stuff
+	 */
+	if (strncasecmp("flags=", *argv, sizeof("flags=") - 1) == 0) {
+	    for (cp = *argv + sizeof("flags=") - 1; *cp; cp++) {
+		switch (*cp) {
+		case 'B':
+		    attr->flags |= MAIL_COPY_BLANK;
+		    break;
+		case 'D':
+		    attr->flags |= MAIL_COPY_DELIVERED;
+		    break;
+		case 'F':
+		    attr->flags |= MAIL_COPY_FROM;
+		    break;
+		case 'O':
+		    attr->flags |= MAIL_COPY_ORIG_RCPT;
+		    break;
+		case 'R':
+		    attr->flags |= MAIL_COPY_RETURN_PATH;
+		    break;
+		case 'X':
+		    attr->flags |= PIPE_OPT_FINAL_DELIVERY;
+		    break;
+		case '.':
+		    attr->flags |= MAIL_COPY_DOT;
+		    break;
+		case '>':
+		    attr->flags |= MAIL_COPY_QUOTE;
+		    break;
+		case 'h':
+		    attr->flags |= PIPE_OPT_FOLD_HOST;
+		    break;
+		case 'q':
+		    attr->flags |= PIPE_OPT_QUOTE_LOCAL;
+		    break;
+		case 'u':
+		    attr->flags |= PIPE_OPT_FOLD_USER;
+		    break;
+		default:
+		    msg_fatal("unknown flag: %c (ignored)", *cp);
+		    break;
+		}
+	    }
+	}
+
+	/*
+	 * user=username[:groupname]
+	 */
+	else if (strncasecmp("user=", *argv, sizeof("user=") - 1) == 0) {
+	    user = *argv + sizeof("user=") - 1;
+	    if ((group = split_at(user, ':')) != 0)	/* XXX clobbers argv */
+		if (*group == 0)
+		    group = 0;
+	    if ((pwd = getpwnam(user)) == 0)
+		msg_fatal("%s: unknown username: %s", myname, user);
+	    attr->uid = pwd->pw_uid;
+	    if (group != 0) {
+		if ((grp = getgrnam(group)) == 0)
+		    msg_fatal("%s: unknown group: %s", myname, group);
+		attr->gid = grp->gr_gid;
+	    } else {
+		attr->gid = pwd->pw_gid;
+	    }
+	}
+
+	/*
+	 * directory=string
+	 */
+	else if (strncasecmp("directory=", *argv, sizeof("directory=") - 1) == 0) {
+	    attr->exec_dir = mystrdup(*argv + sizeof("directory=") - 1);
+	}
+
+	/*
+	 * chroot=string
+	 */
+	else if (strncasecmp("chroot=", *argv, sizeof("chroot=") - 1) == 0) {
+	    attr->chroot_dir = mystrdup(*argv + sizeof("chroot=") - 1);
+	}
+
+	/*
+	 * eol=string
+	 */
+	else if (strncasecmp("eol=", *argv, sizeof("eol=") - 1) == 0) {
+	    unescape(attr->eol, *argv + sizeof("eol=") - 1);
+	}
+
+	/*
+	 * null_sender=string
+	 */
+	else if (strncasecmp("null_sender=", *argv, sizeof("null_sender=") - 1) == 0) {
+	    vstring_strcpy(attr->null_sender, *argv + sizeof("null_sender=") - 1);
+	}
+
+	/*
+	 * size=max_message_size (in bytes)
+	 */
+	else if (strncasecmp("size=", *argv, sizeof("size=") - 1) == 0) {
+	    size = *argv + sizeof("size=") - 1;
+	    if ((attr->size_limit = off_cvt_string(size)) < 0)
+		msg_fatal("%s: bad size= value: %s", myname, size);
+	}
+
+	/*
+	 * argv=command...
+	 */
+	else if (strncasecmp("argv=", *argv, sizeof("argv=") - 1) == 0) {
+	    *argv += sizeof("argv=") - 1;	/* XXX clobbers argv */
+	    attr->command = argv;
+	    break;
+	}
+
+	/*
+	 * Bad.
+	 */
+	else
+	    msg_fatal("unknown attribute name: %s", *argv);
+    }
+
+    /*
+     * Sanity checks. Verify that every member has an acceptable value.
+     */
+    if (user == 0)
+	msg_fatal("missing user= command-line attribute");
+    if (attr->command == 0)
+	msg_fatal("missing argv= command-line attribute");
+    if (attr->uid == 0)
+	msg_fatal("user= command-line attribute specifies root privileges");
+    if (attr->uid == var_owner_uid)
+	msg_fatal("user= command-line attribute specifies mail system owner %s",
+		  var_mail_owner);
+    if (attr->gid == 0)
+	msg_fatal("user= command-line attribute specifies privileged group id 0");
+    if (attr->gid == var_owner_gid)
+	msg_fatal("user= command-line attribute specifies mail system owner %s group id %ld",
+		  var_mail_owner, (long) attr->gid);
+    if (attr->gid == var_sgid_gid)
+	msg_fatal("user= command-line attribute specifies mail system %s group id %ld",
+		  var_sgid_group, (long) attr->gid);
+
+    /*
+     * Give the poor tester a clue of what is going on.
+     */
+    if (msg_verbose)
+	msg_info("%s: uid %ld, gid %ld, flags %d, size %ld",
+		 myname, (long) attr->uid, (long) attr->gid,
+		 attr->flags, (long) attr->size_limit);
+}
+
+/* eval_command_status - do something with command completion status */
+
+static int eval_command_status(int command_status, char *service,
+			          DELIVER_REQUEST *request, PIPE_ATTR *attr,
+			               DSN_BUF *why)
+{
+    RECIPIENT *rcpt;
+    int     status;
+    int     result = 0;
+    int     n;
+    char   *saved_text;
+
+    /*
+     * Depending on the result, bounce or defer the message, and mark the
+     * recipient as done where appropriate.
+     */
+    switch (command_status) {
+    case PIPE_STAT_OK:
+	/* Save the command output before dsb_update() clobbers it. */
+	vstring_truncate(why->reason, trimblanks(STR(why->reason),
+			      VSTRING_LEN(why->reason)) - STR(why->reason));
+	if (VSTRING_LEN(why->reason) > 0) {
+	    VSTRING_TERMINATE(why->reason);
+	    saved_text =
+		vstring_export(vstring_sprintf(
+				    vstring_alloc(VSTRING_LEN(why->reason)),
+					    " (%.100s)", STR(why->reason)));
+	} else
+	    saved_text = mystrdup("");		/* uses shared R/O storage */
+	dsb_update(why, "2.0.0", (attr->flags & PIPE_OPT_FINAL_DELIVERY) ?
+		   "delivered" : "relayed", DSB_SKIP_RMTA, DSB_SKIP_REPLY,
+		   "delivered via %s service%s", service, saved_text);
+	myfree(saved_text);
+	(void) DSN_FROM_DSN_BUF(why);
+	for (n = 0; n < request->rcpt_list.len; n++) {
+	    rcpt = request->rcpt_list.info + n;
+	    status = sent(DEL_REQ_TRACE_FLAGS(request->flags),
+			  request->queue_id, &request->msg_stats, rcpt,
+			  service, &why->dsn);
+	    if (status == 0 && (request->flags & DEL_REQ_FLAG_SUCCESS))
+		deliver_completed(request->fp, rcpt->offset);
+	    result |= status;
+	}
+	break;
+    case PIPE_STAT_BOUNCE:
+    case PIPE_STAT_DEFER:
+	(void) DSN_FROM_DSN_BUF(why);
+	for (n = 0; n < request->rcpt_list.len; n++) {
+	    rcpt = request->rcpt_list.info + n;
+	    /* XXX Maybe encapsulate this with ndr_append(). */
+	    status = (STR(why->status)[0] != '4' ?
+		      bounce_append : defer_append)
+		(DEL_REQ_TRACE_FLAGS(request->flags),
+		 request->queue_id,
+		 &request->msg_stats, rcpt,
+		 service, &why->dsn);
+	    if (status == 0)
+		deliver_completed(request->fp, rcpt->offset);
+	    result |= status;
+	}
+	break;
+    case PIPE_STAT_CORRUPT:
+	/* XXX DSN should we send something? */
+	result |= DEL_STAT_DEFER;
+	break;
+    default:
+	msg_panic("eval_command_status: bad status %d", command_status);
+	/* NOTREACHED */
+    }
+
+    return (result);
+}
+
+/* deliver_message - deliver message with extreme prejudice */
+
+static int deliver_message(DELIVER_REQUEST *request, char *service, char **argv)
+{
+    const char *myname = "deliver_message";
+    static PIPE_PARAMS conf;
+    static PIPE_ATTR attr;
+    RECIPIENT_LIST *rcpt_list = &request->rcpt_list;
+    DSN_BUF *why = dsb_create();
+    VSTRING *buf;
+    ARGV   *expanded_argv = 0;
+    int     deliver_status;
+    int     command_status;
+    ARGV   *export_env;
+    const char *sender;
+
+#define DELIVER_MSG_CLEANUP() { \
+	dsb_free(why); \
+	if (expanded_argv) argv_free(expanded_argv); \
+    }
+
+    if (msg_verbose)
+	msg_info("%s: from <%s>", myname, request->sender);
+
+    /*
+     * Sanity checks. The get_service_params() and get_service_attr()
+     * routines also do some sanity checks. Look up service attributes and
+     * config information only once. This is safe since the information comes
+     * from a trusted source, not from the delivery request.
+     */
+    if (request->nexthop[0] == 0)
+	msg_fatal("empty nexthop hostname");
+    if (rcpt_list->len <= 0)
+	msg_fatal("recipient count: %d", rcpt_list->len);
+    if (attr.command == 0) {
+	get_service_params(&conf, service);
+	get_service_attr(&attr, argv);
+    }
+
+    /*
+     * The D flag cannot be specified for multi-recipient deliveries.
+     */
+    if ((attr.flags & MAIL_COPY_DELIVERED) && (rcpt_list->len > 1)) {
+	dsb_simple(why, "4.3.5", "mail system configuration error");
+	deliver_status = eval_command_status(PIPE_STAT_DEFER, service,
+					     request, &attr, why);
+	msg_warn("pipe flag `D' requires %s_destination_recipient_limit = 1",
+		 service);
+	DELIVER_MSG_CLEANUP();
+	return (deliver_status);
+    }
+
+    /*
+     * The O flag cannot be specified for multi-recipient deliveries.
+     */
+    if ((attr.flags & MAIL_COPY_ORIG_RCPT) && (rcpt_list->len > 1)) {
+	dsb_simple(why, "4.3.5", "mail system configuration error");
+	deliver_status = eval_command_status(PIPE_STAT_DEFER, service,
+					     request, &attr, why);
+	msg_warn("pipe flag `O' requires %s_destination_recipient_limit = 1",
+		 service);
+	DELIVER_MSG_CLEANUP();
+	return (deliver_status);
+    }
+
+    /*
+     * Check that this agent accepts messages this large.
+     */
+    if (attr.size_limit != 0 && request->data_size > attr.size_limit) {
+	if (msg_verbose)
+	    msg_info("%s: too big: size_limit = %ld, request->data_size = %ld",
+		     myname, (long) attr.size_limit, request->data_size);
+	dsb_simple(why, "5.2.3", "message too large");
+	deliver_status = eval_command_status(PIPE_STAT_BOUNCE, service,
+					     request, &attr, why);
+	DELIVER_MSG_CLEANUP();
+	return (deliver_status);
+    }
+
+    /*
+     * Don't deliver a trace-only request.
+     */
+    if (DEL_REQ_TRACE_ONLY(request->flags)) {
+	RECIPIENT *rcpt;
+	int     status;
+	int     n;
+
+	deliver_status = 0;
+	dsb_simple(why, "2.0.0", "delivers to command: %s", attr.command[0]);
+	(void) DSN_FROM_DSN_BUF(why);
+	for (n = 0; n < request->rcpt_list.len; n++) {
+	    rcpt = request->rcpt_list.info + n;
+	    status = sent(DEL_REQ_TRACE_FLAGS(request->flags),
+			  request->queue_id, &request->msg_stats,
+			  rcpt, service, &why->dsn);
+	    if (status == 0 && (request->flags & DEL_REQ_FLAG_SUCCESS))
+		deliver_completed(request->fp, rcpt->offset);
+	    deliver_status |= status;
+	}
+	DELIVER_MSG_CLEANUP();
+	return (deliver_status);
+    }
+
+    /*
+     * Report mail delivery loops. By definition, this requires
+     * single-recipient delivery. Don't silently lose recipients.
+     */
+    if (attr.flags & MAIL_COPY_DELIVERED) {
+	DELIVERED_HDR_INFO *info;
+	RECIPIENT *rcpt;
+	int     loop_found;
+
+	if (request->rcpt_list.len > 1)
+	    msg_panic("%s: delivered-to enabled with multi-recipient request",
+		      myname);
+	info = delivered_hdr_init(request->fp, request->data_offset,
+				  FOLD_ADDR_ALL);
+	rcpt = request->rcpt_list.info;
+	loop_found = delivered_hdr_find(info, rcpt->address);
+	delivered_hdr_free(info);
+	if (loop_found) {
+	    dsb_simple(why, "5.4.6", "mail forwarding loop for %s",
+		       rcpt->address);
+	    deliver_status = eval_command_status(PIPE_STAT_BOUNCE, service,
+						 request, &attr, why);
+	    DELIVER_MSG_CLEANUP();
+	    return (deliver_status);
+	}
+    }
+
+    /*
+     * Deliver. Set the nexthop and sender variables, and expand the command
+     * argument vector. Recipients will be expanded on the fly. XXX Rewrite
+     * envelope and header addresses according to transport-specific
+     * rewriting rules.
+     */
+    if (vstream_fseek(request->fp, request->data_offset, SEEK_SET) < 0)
+	msg_fatal("seek queue file %s: %m", VSTREAM_PATH(request->fp));
+
+    /*
+     * A non-empty null sender replacement is subject to the 'q' flag.
+     */
+    buf = vstring_alloc(10);
+    sender = *request->sender ? request->sender : STR(attr.null_sender);
+    if (*sender && (attr.flags & PIPE_OPT_QUOTE_LOCAL)) {
+	quote_822_local(buf, sender);
+	dict_update(PIPE_DICT_TABLE, PIPE_DICT_SENDER, STR(buf));
+    } else
+	dict_update(PIPE_DICT_TABLE, PIPE_DICT_SENDER, sender);
+    if (attr.flags & PIPE_OPT_FOLD_HOST) {
+	casefold(buf, request->nexthop);
+	dict_update(PIPE_DICT_TABLE, PIPE_DICT_NEXTHOP, STR(buf));
+    } else
+	dict_update(PIPE_DICT_TABLE, PIPE_DICT_NEXTHOP, request->nexthop);
+    vstring_sprintf(buf, "%ld", (long) request->data_size);
+    dict_update(PIPE_DICT_TABLE, PIPE_DICT_SIZE, STR(buf));
+    dict_update(PIPE_DICT_TABLE, PIPE_DICT_CLIENT_ADDR,
+		request->client_addr);
+    dict_update(PIPE_DICT_TABLE, PIPE_DICT_CLIENT_HELO,
+		request->client_helo);
+    dict_update(PIPE_DICT_TABLE, PIPE_DICT_CLIENT_NAME,
+		request->client_name);
+    dict_update(PIPE_DICT_TABLE, PIPE_DICT_CLIENT_PORT,
+		request->client_port);
+    dict_update(PIPE_DICT_TABLE, PIPE_DICT_CLIENT_PROTO,
+		request->client_proto);
+    dict_update(PIPE_DICT_TABLE, PIPE_DICT_SASL_METHOD,
+		request->sasl_method);
+    dict_update(PIPE_DICT_TABLE, PIPE_DICT_SASL_USERNAME,
+		request->sasl_username);
+    dict_update(PIPE_DICT_TABLE, PIPE_DICT_SASL_SENDER,
+		request->sasl_sender);
+    dict_update(PIPE_DICT_TABLE, PIPE_DICT_QUEUE_ID,
+		request->queue_id);
+    vstring_free(buf);
+
+    if ((expanded_argv = expand_argv(service, attr.command,
+				     rcpt_list, attr.flags)) == 0) {
+	dsb_simple(why, "4.3.5", "mail system configuration error");
+	deliver_status = eval_command_status(PIPE_STAT_DEFER, service,
+					     request, &attr, why);
+	DELIVER_MSG_CLEANUP();
+	return (deliver_status);
+    }
+    export_env = mail_parm_split(VAR_EXPORT_ENVIRON, var_export_environ);
+
+    command_status = pipe_command(request->fp, why,
+				  CA_PIPE_CMD_UID(attr.uid),
+				  CA_PIPE_CMD_GID(attr.gid),
+				  CA_PIPE_CMD_SENDER(sender),
+				  CA_PIPE_CMD_COPY_FLAGS(attr.flags),
+				  CA_PIPE_CMD_ARGV(expanded_argv->argv),
+				  CA_PIPE_CMD_TIME_LIMIT(conf.time_limit),
+				  CA_PIPE_CMD_EOL(STR(attr.eol)),
+				  CA_PIPE_CMD_EXPORT(export_env->argv),
+				  CA_PIPE_CMD_CWD(attr.exec_dir),
+				  CA_PIPE_CMD_CHROOT(attr.chroot_dir),
+			CA_PIPE_CMD_ORIG_RCPT(rcpt_list->info[0].orig_addr),
+			  CA_PIPE_CMD_DELIVERED(rcpt_list->info[0].address),
+				  CA_PIPE_CMD_END);
+    argv_free(export_env);
+
+    deliver_status = eval_command_status(command_status, service, request,
+					 &attr, why);
+
+    /*
+     * Clean up.
+     */
+    DELIVER_MSG_CLEANUP();
+
+    return (deliver_status);
+}
+
+/* pipe_service - perform service for client */
+
+static void pipe_service(VSTREAM *client_stream, char *service, char **argv)
+{
+    DELIVER_REQUEST *request;
+    int     status;
+
+    /*
+     * This routine runs whenever a client connects to the UNIX-domain socket
+     * dedicated to delivery via external command. What we see below is a
+     * little protocol to (1) tell the queue manager that we are ready, (2)
+     * read a request from the queue manager, and (3) report the completion
+     * status of that request. All connection-management stuff is handled by
+     * the common code in single_server.c.
+     */
+    if ((request = deliver_request_read(client_stream)) != 0) {
+	status = deliver_message(request, service, argv);
+	deliver_request_done(client_stream, request, status);
+    }
+}
+
+/* pre_accept - see if tables have changed */
+
+static void pre_accept(char *unused_name, char **unused_argv)
+{
+    const char *table;
+
+    if ((table = dict_changed_name()) != 0) {
+	msg_info("table %s has changed -- restarting", table);
+	exit(0);
+    }
+}
+
+/* drop_privileges - drop privileges most of the time */
+
+static void drop_privileges(char *unused_name, char **unused_argv)
+{
+    set_eugid(var_owner_uid, var_owner_gid);
+}
+
+/* pre_init - initialize */
+
+static void pre_init(char *unused_name, char **unused_argv)
+{
+    flush_init();
+}
+
+MAIL_VERSION_STAMP_DECLARE;
+
+/* main - pass control to the single-threaded skeleton */
+
+int     main(int argc, char **argv)
+{
+    static const CONFIG_TIME_TABLE time_table[] = {
+	VAR_COMMAND_MAXTIME, DEF_COMMAND_MAXTIME, &var_command_maxtime, 1, 0,
+	0,
+    };
+    static const CONFIG_STR_TABLE str_table[] = {
+	VAR_PIPE_DSN_FILTER, DEF_PIPE_DSN_FILTER, &var_pipe_dsn_filter, 0, 0,
+	0,
+    };
+
+    /*
+     * Fingerprint executables and core dumps.
+     */
+    MAIL_VERSION_STAMP_ALLOCATE;
+
+    single_server_main(argc, argv, pipe_service,
+		       CA_MAIL_SERVER_TIME_TABLE(time_table),
+		       CA_MAIL_SERVER_STR_TABLE(str_table),
+		       CA_MAIL_SERVER_PRE_INIT(pre_init),
+		       CA_MAIL_SERVER_POST_INIT(drop_privileges),
+		       CA_MAIL_SERVER_PRE_ACCEPT(pre_accept),
+		       CA_MAIL_SERVER_PRIVILEGED,
+		       CA_MAIL_SERVER_BOUNCE_INIT(VAR_PIPE_DSN_FILTER,
+						  &var_pipe_dsn_filter),
+		       0);
+}