Adding upstream version 3.8.5.upstream/3.8.5

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

1 files changed, 1643 insertions, 0 deletions

diff --git a/src/smtpstone/smtp-sink.c b/src/smtpstone/smtp-sink.c
new file mode 100644
index 0000000..c34f21d
--- /dev/null
+++ b/src/smtpstone/smtp-sink.c
@@ -0,0 +1,1643 @@
+/*++
+/* NAME
+/*	smtp-sink 1
+/* SUMMARY
+/*	parallelized SMTP/LMTP test server
+/* SYNOPSIS
+/* .fi
+/*	\fBsmtp-sink\fR [\fIoptions\fR] [\fBinet:\fR][\fIhost\fR]:\fIport\fR
+/*	\fIbacklog\fR
+/*
+/*	\fBsmtp-sink\fR [\fIoptions\fR] \fBunix:\fR\fIpathname\fR \fIbacklog\fR
+/* DESCRIPTION
+/*	\fBsmtp-sink\fR listens on the named host (or address) and port.
+/*	It takes SMTP messages from the network and throws them away.
+/*	The purpose is to measure client performance, not protocol
+/*	compliance.
+/*
+/*	\fBsmtp-sink\fR may also be configured to capture each mail
+/*	delivery transaction to file. Since disk latencies are large
+/*	compared to network delays, this mode of operation can
+/*	reduce the maximal performance by several orders of magnitude.
+/*
+/*	Connections can be accepted on IPv4 or IPv6 endpoints, or on
+/*	UNIX-domain sockets.
+/*	IPv4 and IPv6 are the default.
+/*	This program is the complement of the \fBsmtp-source\fR(1) program.
+/*
+/*	Note: this is an unsupported test program. No attempt is made
+/*	to maintain compatibility between successive versions.
+/*
+/*	Arguments:
+/* .IP \fB-4\fR
+/*	Support IPv4 only. This option has no effect when
+/*	Postfix is built without IPv6 support.
+/* .IP \fB-6\fR
+/*	Support IPv6 only. This option is not available when
+/*	Postfix is built without IPv6 support.
+/* .IP \fB-8\fR
+/*	Do not announce 8BITMIME support.
+/* .IP \fB-a\fR
+/*	Do not announce SASL authentication support.
+/* .IP "\fB-A \fIdelay\fR"
+/*	Wait \fIdelay\fR seconds after responding to DATA, then
+/*	abort prematurely with a 550 reply status.  Do not read
+/*	further input from the client; this is an attempt to block
+/*	the client before it sends ".".  Specify a zero delay value
+/*	to abort immediately.
+/* .IP "\fB-b \fIsoft-bounce-reply\fR"
+/*	Use \fIsoft-bounce-reply\fR for soft reject responses.  The
+/*	default reply is "450 4.3.0 Error: command failed".
+/* .IP "\fB-B \fIhard-bounce-reply\fR"
+/*	Use \fIhard-bounce-reply\fR for hard reject responses.  The
+/*	default reply is "500 5.3.0 Error: command failed".
+/* .IP \fB-c\fR
+/*	Display running counters that are updated whenever an SMTP
+/*	session ends, a QUIT command is executed, or when "." is
+/*	received.
+/* .IP \fB-C\fR
+/*	Disable XCLIENT support.
+/* .IP "\fB-d \fIdump-template\fR"
+/*	Dump each mail transaction to a single-message file whose
+/*	name is created by expanding the \fIdump-template\fR via
+/*	strftime(3) and appending a pseudo-random hexadecimal number
+/*	(example: "%Y%m%d%H/%M." expands into "2006081203/05.809a62e3").
+/*	If the template contains "/" characters, missing directories
+/*	are created automatically.  The message dump format is
+/*	described below.
+/* .sp
+/*	Note: this option keeps one capture file open for every
+/*	mail transaction in progress.
+/* .IP "\fB-D \fIdump-template\fR"
+/*	Append mail transactions to a multi-message dump file whose
+/*	name is created by expanding the \fIdump-template\fR via
+/*	strftime(3).
+/*	If the template contains "/" characters, missing directories
+/*	are created automatically.  The message dump format is
+/*	described below.
+/* .sp
+/*	Note: this option keeps one capture file open for every
+/*	mail transaction in progress.
+/* .IP \fB-e\fR
+/*	Do not announce ESMTP support.
+/* .IP \fB-E\fR
+/*	Do not announce ENHANCEDSTATUSCODES support.
+/* .IP "\fB-f \fIcommand,command,...\fR"
+/*	Reject the specified commands with a hard (5xx) error code.
+/*	This option implies \fB-p\fR.
+/* .sp
+/*	Examples of commands are CONNECT, HELO, EHLO, LHLO, MAIL, RCPT, VRFY,
+/*	DATA, ., RSET, NOOP, and QUIT. Separate command names by
+/*	white space or commas, and use quotes to protect white space
+/*	from the shell. Command names are case-insensitive.
+/* .IP \fB-F\fR
+/*	Disable XFORWARD support.
+/* .IP "\fB-h\fI hostname\fR"
+/*	Use \fIhostname\fR in the SMTP greeting, in the HELO response,
+/*	and in the EHLO response. The default hostname is "smtp-sink".
+/* .IP "\fB-H\fI delay\fR"
+/*	Delay the first read operation after receiving DATA (time
+/*	in seconds). Combine with a large test message and a small
+/*	TCP window size (see the \fB-T\fR option) to test the Postfix
+/*	client write_wait() implementation.
+/* .IP \fB-L\fR
+/*	Enable LMTP instead of SMTP.
+/* .IP "\fB-m \fIcount\fR (default: 256)"
+/*	An upper bound on the maximal number of simultaneous
+/*	connections that \fBsmtp-sink\fR will handle. This prevents
+/*	the process from running out of file descriptors. Excess
+/*	connections will stay queued in the TCP/IP stack.
+/* .IP "\fB-M \fIcount\fR"
+/*	Terminate after receiving \fIcount\fR messages.
+/* .IP "\fB-n \fIcount\fR"
+/*	Terminate after \fIcount\fR sessions.
+/* .IP \fB-N\fR
+/*	Do not announce support for DSN.
+/* .IP \fB-p\fR
+/*	Do not announce support for ESMTP command pipelining.
+/* .IP \fB-P\fR
+/*	Change the server greeting so that it appears to come through
+/*	a CISCO PIX system. Implies \fB-e\fR.
+/* .IP "\fB-q \fIcommand,command,...\fR"
+/*	Disconnect (without replying) after receiving one of the
+/*	specified commands.
+/* .sp
+/*	Examples of commands are CONNECT, HELO, EHLO, LHLO, MAIL, RCPT, VRFY,
+/*	DATA, ., RSET, NOOP, and QUIT. Separate command names by
+/*	white space or commas, and use quotes to protect white space
+/*	from the shell. Command names are case-insensitive.
+/* .IP "\fB-Q \fIcommand,command,...\fR"
+/*	Send a 421 reply and disconnect after receiving one
+/*	of the specified commands.
+/* .sp
+/*	Examples of commands are CONNECT, HELO, EHLO, LHLO, MAIL, RCPT, VRFY,
+/*	DATA, ., RSET, NOOP, and QUIT. Separate command names by
+/*	white space or commas, and use quotes to protect white space
+/*	from the shell. Command names are case-insensitive.
+/* .IP "\fB-r \fIcommand,command,...\fR"
+/*	Reject the specified commands with a soft (4xx) error code.
+/*	This option implies \fB-p\fR.
+/* .sp
+/*	Examples of commands are CONNECT, HELO, EHLO, LHLO, MAIL, RCPT, VRFY,
+/*	DATA, ., RSET, NOOP, and QUIT. Separate command names by
+/*	white space or commas, and use quotes to protect white space
+/*	from the shell. Command names are case-insensitive.
+/* .IP "\fB-R \fIroot-directory\fR"
+/*	Change the process root directory to the specified location.
+/*	This option requires super-user privileges. See also the
+/*	\fB-u\fR option.
+/* .IP "\fB-s \fIcommand,command,...\fR"
+/*	Log the named commands to syslogd.
+/* .sp
+/*	Examples of commands are CONNECT, HELO, EHLO, LHLO, MAIL, RCPT, VRFY,
+/*	DATA, ., RSET, NOOP, and QUIT. Separate command names by
+/*	white space or commas, and use quotes to protect white space
+/*	from the shell. Command names are case-insensitive.
+/* .IP "\fB-S start-string\fR"
+/*	An optional string that is prepended to each message that is
+/*	written to a dump file (see the dump file format description
+/*	below). The following C escape sequences are supported: \ea
+/*	(bell), \eb (backspace), \ef (formfeed), \en (newline), \er
+/*	(carriage return), \et (horizontal tab), \ev (vertical tab),
+/*	\e\fIddd\fR (up to three octal digits) and \e\e (the backslash
+/*	character).
+/* .IP "\fB-t \fItimeout\fR (default: 100)"
+/*	Limit the time for receiving a command or sending a response.
+/*	The time limit is specified in seconds.
+/* .IP "\fB-T \fIwindowsize\fR"
+/*	Override the default TCP window size. To work around
+/*	broken TCP window scaling implementations, specify a
+/*	value > 0 and < 65536.
+/* .IP "\fB-u \fIusername\fR"
+/*	Switch to the specified user privileges after opening the
+/*	network socket and optionally changing the process root
+/*	directory. This option is required when the process runs
+/*	with super-user privileges. See also the \fB-R\fR option.
+/* .IP \fB-v\fR
+/*	Show the SMTP conversations.
+/* .IP "\fB-w \fIdelay\fR"
+/*	Wait \fIdelay\fR seconds before responding to a DATA command.
+/* .IP "\fB-W \fIcommand:delay[:odds]\fR"
+/*	Wait \fIdelay\fR seconds before responding to \fIcommand\fR.
+/*	If \fIodds\fR is also specified (a number between 1-99
+/*	inclusive), wait for a random multiple of \fIdelay\fR. The
+/*	random multiplier is equal to the number of times the program
+/*	needs to roll a dice with a range of 0..99 inclusive, before
+/*	the dice produces a result greater than or equal to \fIodds\fR.
+/* .IP [\fBinet:\fR][\fIhost\fR]:\fIport\fR
+/*	Listen on network interface \fIhost\fR (default: any interface)
+/*	TCP port \fIport\fR. Both \fIhost\fR and \fIport\fR may be
+/*	specified in numeric or symbolic form.
+/* .IP \fBunix:\fR\fIpathname\fR
+/*	Listen on the UNIX-domain socket at \fIpathname\fR.
+/* .IP \fIbacklog\fR
+/*	The maximum length of the queue of pending connections,
+/*	as defined by the \fBlisten\fR(2) system call.
+/* DUMP FILE FORMAT
+/* .ad
+/* .fi
+/*	Each dumped message contains a sequence of text lines,
+/*	terminated with the newline character. The sequence of
+/*	information is as follows:
+/* .IP \(bu
+/*	The optional string specified with the \fB-S\fR option.
+/* .IP \(bu
+/*	The \fBsmtp-sink\fR generated headers as documented below.
+/* .IP \(bu
+/*	The message header and body as received from the SMTP client.
+/* .IP \(bu
+/*	An empty line.
+/* .PP
+/*	The format of the \fBsmtp-sink\fR generated headers is as
+/*	follows:
+/* .IP "\fBX-Client-Addr: \fItext\fR"
+/*	The client IP address without enclosing []. An IPv6 address
+/*	is prefixed with "ipv6:". This record is always present.
+/* .IP "\fBX-Client-Proto: \fItext\fR"
+/*	The client protocol: SMTP, ESMTP or LMTP. This record is
+/*	always present.
+/* .IP "\fBX-Helo-Args: \fItext\fR"
+/*	The arguments of the last HELO or EHLO command before this
+/*	mail delivery transaction. This record is present only if
+/*	the client sent a recognizable HELO or EHLO command before
+/*	the DATA command.
+/* .IP "\fBX-Mail-Args: \fItext\fR"
+/*	The arguments of the MAIL command that started this mail
+/*	delivery transaction. This record is present exactly once.
+/* .IP "\fBX-Rcpt-Args: \fItext\fR"
+/*	The arguments of an RCPT command within this mail delivery
+/*	transaction. There is one record for each RCPT command, and
+/*	they are in the order as sent by the client.
+/* .IP "\fBReceived: \fItext\fR"
+/*	A message header for compatibility with mail processing
+/*	software. This three-line header marks the end of the headers
+/*	provided by \fBsmtp-sink\fR, and is formatted as follows:
+/* .RS
+/* .IP "\fBfrom \fIhelo\fR ([\fIaddr\fR])"
+/*	The HELO or EHLO command argument and client IP address.
+/*	If the client did not send HELO or EHLO, the client IP
+/*	address is used instead.
+/* .IP "\fBby \fIhost\fB (smtp-sink) with \fIproto\fB id \fIrandom\fB;\fR"
+/*	The hostname specified with the \fB-h\fR option, the client
+/*	protocol (see \fBX-Client-Proto\fR above), and the pseudo-random
+/*	portion of the per-message capture file name.
+/* .IP \fItime-stamp\fR
+/*	A time stamp as defined in RFC 2822.
+/* .RE
+/* SEE ALSO
+/*	smtp-source(1), SMTP/LMTP message generator
+/* 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 <sys/socket.h>
+#include <sys/wait.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <string.h>
+#include <stdlib.h>
+#include <fcntl.h>
+#include <syslog.h>
+#include <signal.h>
+#include <time.h>
+#include <ctype.h>
+
+#ifdef STRCASECMP_IN_STRINGS_H
+#include <strings.h>
+#endif
+
+/* Utility library. */
+
+#include <msg.h>
+#include <vstring.h>
+#include <vstream.h>
+#include <vstring_vstream.h>
+#include <get_hostname.h>
+#include <listen.h>
+#include <events.h>
+#include <mymalloc.h>
+#include <iostuff.h>
+#include <msg_vstream.h>
+#include <stringops.h>
+#include <sane_accept.h>
+#include <inet_proto.h>
+#include <myaddrinfo.h>
+#include <make_dirs.h>
+#include <myrand.h>
+#include <chroot_uid.h>
+
+/* Global library. */
+
+#include <smtp_stream.h>
+#include <mail_date.h>
+#include <mail_version.h>
+
+/* Application-specific. */
+
+typedef struct SINK_STATE {
+    VSTREAM *stream;
+    VSTRING *buffer;
+    int     data_state;
+    int     (*read_fn) (struct SINK_STATE *);
+    int     in_mail;
+    int     rcpts;
+    char   *push_back_ptr;
+    /* Capture file information for fake Received: header */
+    MAI_HOSTADDR_STR client_addr;	/* IP address */
+    char   *addr_prefix;		/* ipv6: or empty */
+    char   *helo_args;			/* text after HELO or EHLO */
+    const char *client_proto;		/* SMTP, ESMTP, LMTP */
+    time_t  start_time;			/* MAIL command time */
+    int     id;				/* pseudo-random */
+    VSTREAM *dump_file;			/* dump file or null */
+    void    (*delayed_response) (struct SINK_STATE *state, const char *);
+    char   *delayed_args;
+} SINK_STATE;
+
+#define ST_ANY			0
+#define ST_CR			1
+#define ST_CR_LF		2
+#define ST_CR_LF_DOT		3
+#define ST_CR_LF_DOT_CR		4
+#define ST_CR_LF_DOT_CR_LF	5
+
+#define PUSH_BACK_PEEK(state)		(*(state)->push_back_ptr != 0)
+#define PUSH_BACK_GET(state)		(*(state)->push_back_ptr++)
+#define PUSH_BACK_SET(state, text)	((state)->push_back_ptr = (text))
+
+#ifndef DEF_MAX_CLIENT_COUNT
+#define DEF_MAX_CLIENT_COUNT	256
+#endif
+
+#define SOFT_ERROR_RESP		"450 4.3.0 Error: command failed"
+#define HARD_ERROR_RESP		"500 5.3.0 Error: command failed"
+
+ /*
+  * We can't rely on vstream auto-flushing, so we have to prepare for the
+  * next read request.
+  */
+#define SMTP_FLUSH(fp) do { \
+    if (vstream_peek(fp) <= 0 && readable(vstream_fileno(fp)) <= 0) \
+        smtp_flush(fp); \
+    } while (0)
+
+static int var_tmout = 100;
+static int var_max_line_length = 2048;
+static char *var_myhostname;
+static char *soft_error_resp = SOFT_ERROR_RESP;
+static char *hard_error_resp = HARD_ERROR_RESP;
+static int command_read(SINK_STATE *);
+static int data_read(SINK_STATE *);
+static void disconnect(SINK_STATE *);
+static void read_timeout(int, void *);
+static void read_event(int, void *);
+static int show_count;
+static int sess_count;
+static int quit_count;
+static int mesg_count;
+static int max_quit_count;
+static int max_msg_quit_count;
+static int disable_pipelining;
+static int disable_8bitmime;
+static int disable_esmtp;
+static int enable_lmtp;
+static int pretend_pix;
+static int disable_saslauth;
+static int disable_xclient;
+static int disable_xforward;
+static int disable_enh_status;
+static int disable_dsn;
+static int max_client_count = DEF_MAX_CLIENT_COUNT;
+static int client_count;
+static int sock;
+static int abort_delay = -1;
+static int data_read_delay = 0;
+
+static char *single_template;		/* individual template */
+static char *shared_template;		/* shared template */
+static VSTRING *start_string;		/* dump content prefix */
+
+static const INET_PROTO_INFO *proto_info;
+
+#define STR(x)	vstring_str(x)
+
+/* do_stats - show counters */
+
+static void do_stats(void)
+{
+    vstream_printf("sess=%d quit=%d mesg=%d\r",
+		   sess_count, quit_count, mesg_count);
+    vstream_fflush(VSTREAM_OUT);
+}
+
+/* hard_err_resp - generic hard error response */
+
+static void hard_err_resp(SINK_STATE *state)
+{
+    smtp_printf(state->stream, "%s", hard_error_resp);
+    SMTP_FLUSH(state->stream);
+}
+
+/* soft_err_resp - generic soft error response */
+
+static void soft_err_resp(SINK_STATE *state)
+{
+    smtp_printf(state->stream, "%s", soft_error_resp);
+    SMTP_FLUSH(state->stream);
+}
+
+/* exp_path_template - expand template pathname, static result */
+
+static VSTRING *exp_path_template(const char *template, time_t start_time)
+{
+    static VSTRING *path_buf = 0;
+    struct tm *lt;
+
+    if (path_buf == 0)
+	path_buf = vstring_alloc(100);
+    else
+	VSTRING_RESET(path_buf);
+    lt = localtime(&start_time);
+    while (strftime(STR(path_buf), vstring_avail(path_buf), template, lt) == 0)
+	VSTRING_SPACE(path_buf, vstring_avail(path_buf) + 100);
+    VSTRING_SKIP(path_buf);
+    return (path_buf);
+}
+
+/* make_parent_dir - create parent directory or bust */
+
+static void make_parent_dir(const char *path, mode_t mode)
+{
+    const char *parent;
+
+    parent = sane_dirname((VSTRING *) 0, path);
+    if (make_dirs(parent, mode) < 0)
+	msg_fatal("mkdir %s: %m", parent);
+}
+
+/* mail_file_open - open mail capture file */
+
+static void mail_file_open(SINK_STATE *state)
+{
+    const char *myname = "mail_file_open";
+    VSTRING *path_buf;
+    ssize_t len;
+    int     tries = 0;
+
+    /*
+     * Save the start time for later.
+     */
+    time(&(state->start_time));
+
+    /*
+     * Expand the per-message dumpfile pathname template.
+     */
+    path_buf = exp_path_template(single_template, state->start_time);
+
+    /*
+     * Append a random hexadecimal string to the pathname and create a new
+     * file. Retry with a different path if the file already exists. Create
+     * intermediate directories on the fly when the template specifies
+     * multiple pathname segments.
+     */
+#define ID_FORMAT	"%08x"
+
+    for (len = VSTRING_LEN(path_buf); /* void */ ; vstring_truncate(path_buf, len)) {
+	if (++tries > 100)
+	    msg_fatal("%s: something is looping", myname);
+	state->id = myrand();
+	vstring_sprintf_append(path_buf, ID_FORMAT, state->id);
+	if ((state->dump_file = vstream_fopen(STR(path_buf),
+					      O_RDWR | O_CREAT | O_EXCL,
+					      0644)) != 0) {
+	    break;
+	} else if (errno == EEXIST) {
+	    continue;
+	} else if (errno == ENOENT) {
+	    make_parent_dir(STR(path_buf), 0755);
+	    continue;
+	} else {
+	    msg_fatal("open %s: %m", STR(path_buf));
+	}
+    }
+
+    /*
+     * Don't leave temporary files behind.
+     */
+    if (shared_template != 0 && unlink(STR(path_buf)) < 0)
+	msg_fatal("unlink %s: %m", STR(path_buf));
+
+    /*
+     * Do initial header records.
+     */
+    if (start_string)
+	vstream_fprintf(state->dump_file, "%s", STR(start_string));
+    vstream_fprintf(state->dump_file, "X-Client-Addr: %s%s\n",
+		    state->addr_prefix, state->client_addr.buf);
+    vstream_fprintf(state->dump_file, "X-Client-Proto: %s\n", state->client_proto);
+    if (state->helo_args)
+	vstream_fprintf(state->dump_file, "X-Helo-Args: %s\n", state->helo_args);
+    /* Note: there may be more than one recipient. */
+}
+
+/* mail_file_finish_header - do final smtp-sink generated header records */
+
+static void mail_file_finish_header(SINK_STATE *state)
+{
+    if (state->helo_args)
+	vstream_fprintf(state->dump_file, "Received: from %s ([%s%s])\n",
+			state->helo_args, state->addr_prefix,
+			state->client_addr.buf);
+    else
+	vstream_fprintf(state->dump_file, "Received: from [%s%s] ([%s%s])\n",
+			state->addr_prefix, state->client_addr.buf,
+			state->addr_prefix, state->client_addr.buf);
+    vstream_fprintf(state->dump_file, "\tby %s (smtp-sink)"
+		    " with %s id " ID_FORMAT ";\n",
+		    var_myhostname, state->client_proto, state->id);
+    vstream_fprintf(state->dump_file, "\t%s\n", mail_date(state->start_time));
+}
+
+/* mail_file_cleanup - common cleanup for capture file */
+
+static void mail_file_cleanup(SINK_STATE *state)
+{
+    (void) vstream_fclose(state->dump_file);
+    state->dump_file = 0;
+}
+
+/* mail_file_finish - handle message completion for capture file */
+
+static void mail_file_finish(SINK_STATE *state)
+{
+
+    /*
+     * Optionally append the captured message to a shared dumpfile.
+     */
+    if (shared_template) {
+	const char *out_path;
+	VSTREAM *out_fp;
+	ssize_t count;
+
+	/*
+	 * Expand the shared dumpfile pathname template.
+	 */
+	out_path = STR(exp_path_template(shared_template, state->start_time));
+
+	/*
+	 * Open the shared dump file.
+	 */
+#define OUT_OPEN_FLAGS	(O_WRONLY | O_CREAT | O_APPEND)
+#define OUT_OPEN_MODE	0644
+
+	if ((out_fp = vstream_fopen(out_path, OUT_OPEN_FLAGS, OUT_OPEN_MODE))
+	    == 0 && errno == ENOENT) {
+	    make_parent_dir(out_path, 0755);
+	    out_fp = vstream_fopen(out_path, OUT_OPEN_FLAGS, OUT_OPEN_MODE);
+	}
+	if (out_fp == 0)
+	    msg_fatal("open %s: %m", out_path);
+
+	/*
+	 * Append message content from single-message dump file.
+	 */
+	if (vstream_fseek(state->dump_file, 0L, SEEK_SET) < 0)
+	    msg_fatal("seek file %s: %m", VSTREAM_PATH(state->dump_file));
+	VSTRING_RESET(state->buffer);
+	for (;;) {
+	    count = vstream_fread(state->dump_file, STR(state->buffer),
+				  vstring_avail(state->buffer));
+	    if (count <= 0)
+		break;
+	    if (vstream_fwrite(out_fp, STR(state->buffer), count) != count)
+		msg_fatal("append file %s: %m", out_path);
+	}
+	if (vstream_ferror(state->dump_file))
+	    msg_fatal("read file %s: %m", VSTREAM_PATH(state->dump_file));
+	if (vstream_fclose(out_fp))
+	    msg_fatal("append file %s: %m", out_path);
+    }
+    mail_file_cleanup(state);
+}
+
+/* mail_file_reset - abort mail to capture file */
+
+static void mail_file_reset(SINK_STATE *state)
+{
+    if (shared_template == 0
+	&& unlink(VSTREAM_PATH(state->dump_file)) < 0
+	&& errno != ENOENT)
+	msg_fatal("unlink %s: %m", VSTREAM_PATH(state->dump_file));
+    mail_file_cleanup(state);
+}
+
+/* mail_cmd_reset - reset mail transaction information */
+
+static void mail_cmd_reset(SINK_STATE *state)
+{
+    state->in_mail = 0;
+    /* Not: state->rcpts = 0. This breaks the DOT reply with LMTP. */
+    if (state->dump_file)
+	mail_file_reset(state);
+}
+
+/* ehlo_response - respond to EHLO command */
+
+static void ehlo_response(SINK_STATE *state, const char *args)
+{
+#define SKIP(cp, cond) do { \
+	for (/* void */; *cp && (cond); cp++) \
+	    /* void */; \
+    } while (0)
+
+    /* EHLO aborts a mail transaction in progress. */
+    mail_cmd_reset(state);
+    if (enable_lmtp == 0)
+	state->client_proto = "ESMTP";
+    smtp_printf(state->stream, "250-%s", var_myhostname);
+    if (!disable_pipelining)
+	smtp_printf(state->stream, "250-PIPELINING");
+    if (!disable_8bitmime)
+	smtp_printf(state->stream, "250-8BITMIME");
+    if (!disable_saslauth)
+	smtp_printf(state->stream, "250-AUTH PLAIN LOGIN");
+    if (!disable_xclient)
+	smtp_printf(state->stream, "250-XCLIENT NAME HELO");
+    if (!disable_xforward)
+	smtp_printf(state->stream, "250-XFORWARD NAME ADDR PROTO HELO");
+    if (!disable_enh_status)
+	smtp_printf(state->stream, "250-ENHANCEDSTATUSCODES");
+    if (!disable_dsn)
+	smtp_printf(state->stream, "250-DSN");
+    /* RFC 821/2821/5321: Format is replycode<SPACE>optional-text<CRLF> */
+    smtp_printf(state->stream, "250 ");
+    SMTP_FLUSH(state->stream);
+    if (single_template) {
+	if (state->helo_args)
+	    myfree(state->helo_args);
+	SKIP(args, ISSPACE(*args));
+	state->helo_args = mystrdup(args);
+    }
+}
+
+/* helo_response - respond to HELO command */
+
+static void helo_response(SINK_STATE *state, const char *args)
+{
+    /* HELO aborts a mail transaction in progress. */
+    mail_cmd_reset(state);
+    state->client_proto = "SMTP";
+    smtp_printf(state->stream, "250 %s", var_myhostname);
+    SMTP_FLUSH(state->stream);
+    if (single_template) {
+	if (state->helo_args)
+	    myfree(state->helo_args);
+	SKIP(args, ISSPACE(*args));
+	state->helo_args = mystrdup(args);
+    }
+}
+
+/* ok_response - send 250 OK */
+
+static void ok_response(SINK_STATE *state, const char *unused_args)
+{
+    smtp_printf(state->stream, "250 2.0.0 Ok");
+    SMTP_FLUSH(state->stream);
+}
+
+/* rset_response - reset, send 250 OK */
+
+static void rset_response(SINK_STATE *state, const char *unused_args)
+{
+    mail_cmd_reset(state);
+    smtp_printf(state->stream, "250 2.1.0 Ok");
+    SMTP_FLUSH(state->stream);
+}
+
+/* mail_response - reset recipient count, send 250 OK */
+
+static void mail_response(SINK_STATE *state, const char *args)
+{
+    if (state->in_mail) {
+	smtp_printf(state->stream, "503 5.5.1 Error: nested MAIL command");
+	SMTP_FLUSH(state->stream);
+	return;
+    }
+    state->in_mail++;
+    state->rcpts = 0;
+    smtp_printf(state->stream, "250 2.1.0 Ok");
+    SMTP_FLUSH(state->stream);
+    if (single_template) {
+	mail_file_open(state);
+	SKIP(args, *args != ':');
+	SKIP(args, *args == ':');
+	SKIP(args, ISSPACE(*args));
+	vstream_fprintf(state->dump_file, "X-Mail-Args: %s\n", args);
+    }
+}
+
+/* rcpt_response - bump recipient count, send 250 OK */
+
+static void rcpt_response(SINK_STATE *state, const char *args)
+{
+    if (state->in_mail == 0) {
+	smtp_printf(state->stream, "503 5.5.1 Error: need MAIL command");
+	SMTP_FLUSH(state->stream);
+	return;
+    }
+    state->rcpts++;
+    smtp_printf(state->stream, "250 2.1.5 Ok");
+    SMTP_FLUSH(state->stream);
+    /* Note: there may be more than one recipient per mail transaction. */
+    if (state->dump_file) {
+	SKIP(args, *args != ':');
+	SKIP(args, *args == ':');
+	SKIP(args, ISSPACE(*args));
+	vstream_fprintf(state->dump_file, "X-Rcpt-Args: %s\n", args);
+    }
+}
+
+/* abort_event - delayed abort after DATA command */
+
+static void abort_event(int unused_event, void *context)
+{
+    SINK_STATE *state = (SINK_STATE *) context;
+
+    smtp_printf(state->stream, "550 This violates SMTP");
+    SMTP_FLUSH(state->stream);
+    disconnect(state);
+}
+
+/* delay_read_event - resume input event handling */
+
+static void delay_read_event(int event, void *context)
+{
+    SINK_STATE *state = (SINK_STATE *) context;
+
+    if (event != EVENT_TIME)
+	msg_panic("delay_read_event: non-timer event %d", event);
+
+    event_enable_read(vstream_fileno(state->stream), read_event, (void *) state);
+    event_request_timer(read_timeout, (void *) state, var_tmout);
+}
+
+/* delay_read - temporarily suspend input event handling */
+
+static void delay_read(SINK_STATE *state, int delay)
+{
+    event_disable_readwrite(vstream_fileno(state->stream));
+    event_cancel_timer(read_timeout, (void *) state);
+    event_request_timer(delay_read_event, (void *) state, delay);
+}
+
+/* data_response - respond to DATA command */
+
+static void data_response(SINK_STATE *state, const char *unused_args)
+{
+    if (state->in_mail == 0 || state->rcpts == 0) {
+	smtp_printf(state->stream, "503 5.5.1 Error: need RCPT command");
+	SMTP_FLUSH(state->stream);
+	return;
+    }
+    /* Not: ST_ANY. */
+    state->data_state = ST_CR_LF;
+    smtp_printf(state->stream, "354 End data with <CR><LF>.<CR><LF>");
+    SMTP_FLUSH(state->stream);
+    if (abort_delay < 0) {
+	state->read_fn = data_read;
+	/* Todo: move into code that invokes the command response function. */
+	if (data_read_delay > 0)
+	    delay_read(state, data_read_delay);
+    } else {
+	/* Stop reading, send premature 550, and disconnect. */
+	event_disable_readwrite(vstream_fileno(state->stream));
+	event_cancel_timer(read_event, (void *) state);
+	event_request_timer(abort_event, (void *) state, abort_delay);
+    }
+    if (state->dump_file)
+	mail_file_finish_header(state);
+}
+
+/* dot_resp_hard - hard error response to . command */
+
+static void dot_resp_hard(SINK_STATE *state)
+{
+    if (enable_lmtp) {
+	while (state->rcpts-- > 0)	/* XXX this could block */
+	    smtp_printf(state->stream, "%s", hard_error_resp);
+    } else {
+	smtp_printf(state->stream, "%s", hard_error_resp);
+    }
+    SMTP_FLUSH(state->stream);
+}
+
+/* dot_resp_soft - soft error response to . command */
+
+static void dot_resp_soft(SINK_STATE *state)
+{
+    if (enable_lmtp) {
+	while (state->rcpts-- > 0)	/* XXX this could block */
+	    smtp_printf(state->stream, "%s", soft_error_resp);
+    } else {
+	smtp_printf(state->stream, "%s", soft_error_resp);
+    }
+    SMTP_FLUSH(state->stream);
+}
+
+/* dot_response - response to . command */
+
+static void dot_response(SINK_STATE *state, const char *unused_args)
+{
+    if (enable_lmtp) {
+	while (state->rcpts-- > 0)	/* XXX this could block */
+	    smtp_printf(state->stream, "250 2.2.0 Ok");
+    } else {
+	smtp_printf(state->stream, "250 2.0.0 Ok");
+    }
+    SMTP_FLUSH(state->stream);
+}
+
+/* quit_response - respond to QUIT command */
+
+static void quit_response(SINK_STATE *state, const char *unused_args)
+{
+    smtp_printf(state->stream, "221 Bye");
+    smtp_flush(state->stream);			/* not: SMTP_FLUSH */
+    if (show_count)
+	quit_count++;
+}
+
+/* conn_response - respond to connect command */
+
+static void conn_response(SINK_STATE *state, const char *unused_args)
+{
+    if (pretend_pix)
+	smtp_printf(state->stream, "220 ********");
+    else if (disable_esmtp)
+	smtp_printf(state->stream, "220 %s", var_myhostname);
+    else
+	smtp_printf(state->stream, "220 %s ESMTP", var_myhostname);
+    SMTP_FLUSH(state->stream);
+}
+
+/* delay_event - delayed command response */
+
+static void delay_event(int unused_event, void *context)
+{
+    SINK_STATE *state = (SINK_STATE *) context;
+
+    switch (vstream_setjmp(state->stream)) {
+
+    default:
+	msg_panic("unknown read/write error");
+	/* NOTREACHED */
+
+    case SMTP_ERR_TIME:
+	msg_warn("write timeout");
+	disconnect(state);
+	return;
+
+    case SMTP_ERR_EOF:
+	msg_warn("lost connection");
+	disconnect(state);
+	return;
+
+    case 0:
+	state->delayed_response(state, state->delayed_args);
+	myfree(state->delayed_args);
+	state->delayed_args = 0;
+	break;
+    }
+
+    if (state->delayed_response == quit_response) {
+	disconnect(state);
+	return;
+    }
+    state->delayed_response = 0;
+
+    /* Resume input event handling after the delayed response. */
+    event_enable_read(vstream_fileno(state->stream), read_event, (void *) state);
+    event_request_timer(read_timeout, (void *) state, var_tmout);
+}
+
+/* data_read - read data from socket */
+
+static int data_read(SINK_STATE *state)
+{
+    int     ch;
+    struct data_trans {
+	int     state;
+	int     want;
+	int     next_state;
+    };
+    static struct data_trans data_trans[] = {
+	ST_ANY, '\r', ST_CR,
+	ST_CR, '\n', ST_CR_LF,
+	ST_CR_LF, '.', ST_CR_LF_DOT,
+	ST_CR_LF_DOT, '\r', ST_CR_LF_DOT_CR,
+	ST_CR_LF_DOT_CR, '\n', ST_CR_LF_DOT_CR_LF,
+    };
+    struct data_trans *dp;
+
+    /*
+     * A read may result in EOF, but is never supposed to time out - a time
+     * out means that we were trying to read when no data was available.
+     */
+    for (;;) {
+	if ((ch = VSTREAM_GETC(state->stream)) == VSTREAM_EOF)
+	    return (-1);
+	for (dp = data_trans; dp->state != state->data_state; dp++)
+	     /* void */ ;
+
+	/*
+	 * Try to match the current character desired by the state machine.
+	 * If that fails, try to restart the machine with a match for its
+	 * first state.  This covers the case of a CR/LF/CR/LF sequence
+	 * (empty line) right before the end of the message data.
+	 */
+	if (ch == dp->want)
+	    state->data_state = dp->next_state;
+	else if (ch == data_trans[0].want)
+	    state->data_state = data_trans[0].next_state;
+	else
+	    state->data_state = ST_ANY;
+	if (state->dump_file) {
+	    if (ch != '\r' && state->data_state != ST_CR_LF_DOT)
+		VSTREAM_PUTC(ch, state->dump_file);
+	    if (vstream_ferror(state->dump_file))
+		msg_fatal("append file %s: %m", VSTREAM_PATH(state->dump_file));
+	}
+	if (state->data_state == ST_CR_LF_DOT_CR_LF) {
+	    PUSH_BACK_SET(state, ".\r\n");
+	    state->read_fn = command_read;
+	    state->data_state = ST_ANY;
+	    if (state->dump_file)
+		mail_file_finish(state);
+	    mail_cmd_reset(state);
+	    if (show_count || max_msg_quit_count > 0) {
+		mesg_count++;
+		if (show_count)
+		    do_stats();
+		if (max_msg_quit_count > 0 && mesg_count >= max_msg_quit_count)
+		    exit(0);
+	    }
+	    break;
+	}
+
+	/*
+	 * We must avoid blocking I/O, so get out of here as soon as both the
+	 * VSTREAM and kernel read buffers dry up.
+	 */
+	if (vstream_peek(state->stream) <= 0
+	    && readable(vstream_fileno(state->stream)) <= 0)
+	    return (0);
+    }
+    return (0);
+}
+
+ /*
+  * The table of all SMTP commands that we can handle.
+  */
+typedef struct SINK_COMMAND {
+    const char *name;
+    void    (*response) (SINK_STATE *, const char *);
+    void    (*hard_response) (SINK_STATE *);
+    void    (*soft_response) (SINK_STATE *);
+    int     flags;
+    int     delay;
+    int     delay_odds;
+} SINK_COMMAND;
+
+#define FLAG_ENABLE	(1<<0)		/* command is enabled */
+#define FLAG_SYSLOG	(1<<1)		/* log the command */
+#define FLAG_HARD_ERR	(1<<2)		/* report hard error */
+#define FLAG_SOFT_ERR	(1<<3)		/* report soft error */
+#define FLAG_DISCONNECT	(1<<4)		/* disconnect */
+#define FLAG_CLOSE	(1<<5)		/* say goodbye and disconnect */
+
+static SINK_COMMAND command_table[] = {
+    "connect", conn_response, hard_err_resp, soft_err_resp, 0, 0, 0,
+    "helo", helo_response, hard_err_resp, soft_err_resp, 0, 0, 0,
+    "ehlo", ehlo_response, hard_err_resp, soft_err_resp, 0, 0, 0,
+    "lhlo", ehlo_response, hard_err_resp, soft_err_resp, 0, 0, 0,
+    "xclient", ok_response, hard_err_resp, soft_err_resp, FLAG_ENABLE, 0, 0,
+    "xforward", ok_response, hard_err_resp, soft_err_resp, FLAG_ENABLE, 0, 0,
+    "auth", ok_response, hard_err_resp, soft_err_resp, FLAG_ENABLE, 0, 0,
+    "mail", mail_response, hard_err_resp, soft_err_resp, FLAG_ENABLE, 0, 0,
+    "rcpt", rcpt_response, hard_err_resp, soft_err_resp, FLAG_ENABLE, 0, 0,
+    "data", data_response, hard_err_resp, soft_err_resp, FLAG_ENABLE, 0, 0,
+    ".", dot_response, dot_resp_hard, dot_resp_soft, FLAG_ENABLE, 0, 0,
+    "rset", rset_response, hard_err_resp, soft_err_resp, FLAG_ENABLE, 0, 0,
+    "noop", ok_response, hard_err_resp, soft_err_resp, FLAG_ENABLE, 0, 0,
+    "vrfy", ok_response, hard_err_resp, soft_err_resp, FLAG_ENABLE, 0, 0,
+    "quit", quit_response, hard_err_resp, soft_err_resp, FLAG_ENABLE, 0, 0,
+    0,
+};
+
+/* reset_cmd_flags - reset per-command command flags */
+
+static void reset_cmd_flags(const char *cmd, int flags)
+{
+    SINK_COMMAND *cmdp;
+
+    for (cmdp = command_table; cmdp->name != 0; cmdp++)
+	if (strcasecmp(cmd, cmdp->name) == 0)
+	    break;
+    if (cmdp->name == 0)
+	msg_fatal("unknown command: %s", cmd);
+    cmdp->flags &= ~flags;
+}
+
+/* set_cmd_flags - set per-command command flags */
+
+static void set_cmd_flags(const char *cmd, int flags)
+{
+    SINK_COMMAND *cmdp;
+
+    for (cmdp = command_table; cmdp->name != 0; cmdp++)
+	if (strcasecmp(cmd, cmdp->name) == 0)
+	    break;
+    if (cmdp->name == 0)
+	msg_fatal("unknown command: %s", cmd);
+    cmdp->flags |= flags;
+}
+
+/* set_cmds_flags - set per-command flags for multiple commands */
+
+static void set_cmds_flags(const char *cmds, int flags)
+{
+    char   *saved_cmds;
+    char   *cp;
+    char   *cmd;
+
+    saved_cmds = cp = mystrdup(cmds);
+    while ((cmd = mystrtok(&cp, CHARS_COMMA_SP)) != 0)
+	set_cmd_flags(cmd, flags);
+    myfree(saved_cmds);
+}
+
+/* set_cmd_delay - set per-command delay */
+
+static void set_cmd_delay(const char *cmd, int delay, int odds)
+{
+    SINK_COMMAND *cmdp;
+
+    for (cmdp = command_table; cmdp->name != 0; cmdp++)
+	if (strcasecmp(cmd, cmdp->name) == 0)
+	    break;
+    if (cmdp->name == 0)
+	msg_fatal("unknown command: %s", cmd);
+
+    if (delay <= 0)
+	msg_fatal("non-positive '%s' delay", cmd);
+    if (odds < 0 || odds > 99)
+	msg_fatal("delay odds for '%s' out of range", cmd);
+
+    cmdp->delay = delay;
+    cmdp->delay_odds = odds;
+}
+
+/* set_cmd_delay_arg - set per-command delay from option argument */
+
+static void set_cmd_delay_arg(char *arg)
+{
+    char   *cp;
+    char   *saved_arg;
+    char   *cmd;
+    char   *delay;
+    char   *odds;
+
+    saved_arg = cp = mystrdup(arg);
+    cmd = mystrtok(&cp, ":");
+    delay = mystrtok(&cp, ":");
+    if (cmd == 0 || delay == 0)
+	msg_fatal("invalid command delay argument: %s", arg);
+    odds = mystrtok(&cp, "");
+    set_cmd_delay(cmd, atoi(delay), odds ? atoi(odds) : 0);
+    myfree(saved_arg);
+}
+
+/* command_resp - respond to command */
+
+static int command_resp(SINK_STATE *state, SINK_COMMAND *cmdp,
+			        const char *command, const char *args)
+{
+    /* We use raw syslog. Sanitize data content and length. */
+    if (cmdp->flags & FLAG_SYSLOG)
+	syslog(LOG_INFO, "%s %.100s", command, args);
+    if (cmdp->flags & FLAG_DISCONNECT)
+	return (-1);
+    if (cmdp->flags & FLAG_CLOSE) {
+	smtp_printf(state->stream, "421 4.0.0 Server closing connection");
+	return (-1);
+    }
+    if (cmdp->flags & FLAG_HARD_ERR) {
+	cmdp->hard_response(state);
+	return (0);
+    }
+    if (cmdp->flags & FLAG_SOFT_ERR) {
+	cmdp->soft_response(state);
+	return (0);
+    }
+    if (cmdp->delay > 0) {
+	int     delay = cmdp->delay;
+
+	if (cmdp->delay_odds > 0)
+	    for (delay = 0;
+	     ((int) (100.0 * rand() / (RAND_MAX + 1.0))) < cmdp->delay_odds;
+		 delay += cmdp->delay)
+		 /* NOP */ ;
+	/* Suspend input event handling while delaying the command response. */
+	event_disable_readwrite(vstream_fileno(state->stream));
+	event_cancel_timer(read_timeout, (void *) state);
+	event_request_timer(delay_event, (void *) state, delay);
+	state->delayed_response = cmdp->response;
+	state->delayed_args = mystrdup(args);
+    } else {
+	cmdp->response(state, args);
+	if (cmdp->response == quit_response)
+	    return (-1);
+    }
+    return (0);
+}
+
+/* command_read - talk the SMTP protocol, server side */
+
+static int command_read(SINK_STATE *state)
+{
+    char   *command;
+    SINK_COMMAND *cmdp;
+    int     ch;
+    struct cmd_trans {
+	int     state;
+	int     want;
+	int     next_state;
+    };
+    static struct cmd_trans cmd_trans[] = {
+	ST_ANY, '\r', ST_CR,
+	ST_CR, '\n', ST_CR_LF,
+	0, 0, 0,
+    };
+    struct cmd_trans *cp;
+    char   *ptr;
+
+    /*
+     * A read may result in EOF, but is never supposed to time out - a time
+     * out means that we were trying to read when no data was available.
+     */
+#define NEXT_CHAR(state) \
+    (PUSH_BACK_PEEK(state) ? PUSH_BACK_GET(state) : VSTREAM_GETC(state->stream))
+
+    if (state->data_state == ST_CR_LF)
+	state->data_state = ST_ANY;		/* XXX */
+    for (;;) {
+	if ((ch = NEXT_CHAR(state)) == VSTREAM_EOF)
+	    return (-1);
+
+	/*
+	 * Sanity check. We don't want to store infinitely long commands.
+	 */
+	if (VSTRING_LEN(state->buffer) >= var_max_line_length) {
+	    msg_warn("command line too long");
+	    return (-1);
+	}
+	VSTRING_ADDCH(state->buffer, ch);
+
+	/*
+	 * Try to match the current character desired by the state machine.
+	 * If that fails, try to restart the machine with a match for its
+	 * first state.
+	 */
+	for (cp = cmd_trans; cp->state != state->data_state; cp++)
+	    if (cp->want == 0)
+		msg_panic("command_read: unknown state: %d", state->data_state);
+	if (ch == cp->want)
+	    state->data_state = cp->next_state;
+	else if (ch == cmd_trans[0].want)
+	    state->data_state = cmd_trans[0].next_state;
+	else
+	    state->data_state = ST_ANY;
+	if (state->data_state == ST_CR_LF)
+	    break;
+
+	/*
+	 * We must avoid blocking I/O, so get out of here as soon as both the
+	 * VSTREAM and kernel read buffers dry up.
+	 * 
+	 * XXX Solaris non-blocking read() may fail on a socket when ioctl
+	 * FIONREAD reports there is unread data. Diagnosis by Max Pashkov.
+	 * As a workaround we use readable() (which uses poll or select())
+	 * instead of peek_fd() (which uses ioctl FIONREAD). Workaround added
+	 * 20020604.
+	 */
+	if (PUSH_BACK_PEEK(state) == 0 && vstream_peek(state->stream) <= 0
+	    && readable(vstream_fileno(state->stream)) <= 0)
+	    return (0);
+    }
+
+    /*
+     * Properly terminate the result, and reset the buffer write pointer for
+     * reading the next command. This is ugly, but not as ugly as trying to
+     * deal with all the early returns below.
+     */
+    vstring_truncate(state->buffer, VSTRING_LEN(state->buffer) - 2);
+    VSTRING_TERMINATE(state->buffer);
+    state->data_state = ST_CR_LF;
+    VSTRING_RESET(state->buffer);
+
+    /*
+     * Got a complete command line. Parse it.
+     */
+    ptr = vstring_str(state->buffer);
+    if (msg_verbose)
+	msg_info("%s", ptr);
+    if ((command = mystrtok(&ptr, " \t")) == 0) {
+	smtp_printf(state->stream, "500 5.5.2 Error: unknown command");
+	SMTP_FLUSH(state->stream);
+	return (0);
+    }
+    for (cmdp = command_table; cmdp->name != 0; cmdp++)
+	if (strcasecmp(command, cmdp->name) == 0)
+	    break;
+    if (cmdp->name == 0 || (cmdp->flags & FLAG_ENABLE) == 0) {
+	smtp_printf(state->stream, "500 5.5.1 Error: unknown command");
+	SMTP_FLUSH(state->stream);
+	return (0);
+    }
+    return (command_resp(state, cmdp, command, printable(ptr, '?')));
+}
+
+/* read_timeout - handle timer event */
+
+static void read_timeout(int unused_event, void *context)
+{
+    SINK_STATE *state = (SINK_STATE *) context;
+
+    /*
+     * We don't send anything to the client, because we would have to set up
+     * an smtp_stream exception handler first. And that is just too much
+     * trouble.
+     */
+    msg_warn("read timeout");
+    disconnect(state);
+}
+
+/* read_event - handle command or data read events */
+
+static void read_event(int unused_event, void *context)
+{
+    SINK_STATE *state = (SINK_STATE *) context;
+
+    /*
+     * The input reading routine not only reads input (with vstream calls)
+     * but also produces output (with smtp_stream calls). Because the output
+     * routines can raise timeout or EOF exceptions with vstream_longjmp(),
+     * the input reading routine needs to set up corresponding exception
+     * handlers with vstream_setjmp(). Guarding the input operations in the
+     * same manner is not useful: we must read input in non-blocking mode, so
+     * we never get called when the socket stays unreadable too long. And EOF
+     * is already trivial to detect with the vstream calls.
+     */
+    do {
+	switch (vstream_setjmp(state->stream)) {
+
+	default:
+	    msg_panic("unknown read/write error");
+	    /* NOTREACHED */
+
+	case SMTP_ERR_TIME:
+	    msg_warn("write timeout");
+	    disconnect(state);
+	    return;
+
+	case SMTP_ERR_EOF:
+	    msg_warn("lost connection");
+	    disconnect(state);
+	    return;
+
+	case 0:
+	    if (state->read_fn(state) < 0) {
+		if (msg_verbose)
+		    msg_info("disconnect");
+		disconnect(state);
+		return;
+	    }
+	}
+    } while (PUSH_BACK_PEEK(state) != 0 || vstream_peek(state->stream) > 0);
+
+    /*
+     * Reset the idle timer. Wait until the next input event, or until the
+     * idle timer goes off.
+     */
+    event_request_timer(read_timeout, (void *) state, var_tmout);
+}
+
+static void connect_event(int, void *);
+
+/* disconnect - handle disconnection events */
+
+static void disconnect(SINK_STATE *state)
+{
+    event_disable_readwrite(vstream_fileno(state->stream));
+    event_cancel_timer(read_timeout, (void *) state);
+    if (show_count) {
+	sess_count++;
+	do_stats();
+    }
+    vstream_fclose(state->stream);
+    vstring_free(state->buffer);
+    /* Clean up file capture attributes. */
+    if (state->helo_args)
+	myfree(state->helo_args);
+    /* Delete incomplete mail transaction. */
+    mail_cmd_reset(state);
+    if (state->delayed_args)
+	myfree(state->delayed_args);
+    myfree((void *) state);
+    if (max_quit_count > 0 && quit_count >= max_quit_count)
+	exit(0);
+    if (client_count-- == max_client_count)
+	event_enable_read(sock, connect_event, (void *) 0);
+}
+
+/* connect_event - handle connection events */
+
+static void connect_event(int unused_event, void *unused_context)
+{
+    struct sockaddr_storage ss;
+    SOCKADDR_SIZE len = sizeof(ss);
+    struct sockaddr *sa = (struct sockaddr *) &ss;
+    SINK_STATE *state;
+    int     fd;
+
+    if ((fd = sane_accept(sock, sa, &len)) >= 0) {
+	/* Safety: limit the number of open sockets and capture files. */
+	if (++client_count == max_client_count)
+	    event_disable_readwrite(sock);
+	state = (SINK_STATE *) mymalloc(sizeof(*state));
+	if (strchr((char *) proto_info->sa_family_list, sa->sa_family))
+	    SOCKADDR_TO_HOSTADDR(sa, len, &state->client_addr,
+				 (MAI_SERVPORT_STR *) 0, sa->sa_family);
+	else
+	    strncpy(state->client_addr.buf, "local", sizeof("local") + 0);
+	if (msg_verbose)
+	    msg_info("connect (%s %s)",
+#ifdef AF_LOCAL
+		     sa->sa_family == AF_LOCAL ? "AF_LOCAL" :
+#else
+		     sa->sa_family == AF_UNIX ? "AF_UNIX" :
+#endif
+		     sa->sa_family == AF_INET ? "AF_INET" :
+#ifdef AF_INET6
+		     sa->sa_family == AF_INET6 ? "AF_INET6" :
+#endif
+		     "unknown protocol family",
+		     state->client_addr.buf);
+	non_blocking(fd, NON_BLOCKING);
+	state->stream = vstream_fdopen(fd, O_RDWR);
+	vstream_tweak_sock(state->stream);
+	state->buffer = vstring_alloc(1024);
+	state->read_fn = command_read;
+	state->data_state = ST_ANY;
+	PUSH_BACK_SET(state, "");
+	smtp_timeout_setup(state->stream, var_tmout);
+	state->in_mail = 0;
+	state->rcpts = 0;
+	state->delayed_response = 0;
+	state->delayed_args = 0;
+	/* Initialize file capture attributes. */
+#ifdef AF_INET6
+	if (sa->sa_family == AF_INET6)
+	    state->addr_prefix = "ipv6:";
+	else
+#endif
+	    state->addr_prefix = "";
+
+	state->helo_args = 0;
+	state->client_proto = enable_lmtp ? "LMTP" : "SMTP";
+	state->start_time = 0;
+	state->id = 0;
+	state->dump_file = 0;
+
+	/*
+	 * We use the smtp_stream module to produce output. That module
+	 * throws an exception via vstream_longjmp() in case of a timeout or
+	 * lost connection error. Therefore we must prepare to handle these
+	 * exceptions with vstream_setjmp().
+	 */
+	switch (vstream_setjmp(state->stream)) {
+
+	default:
+	    msg_panic("unknown read/write error");
+	    /* NOTREACHED */
+
+	case SMTP_ERR_TIME:
+	    msg_warn("write timeout");
+	    disconnect(state);
+	    return;
+
+	case SMTP_ERR_EOF:
+	    msg_warn("lost connection");
+	    disconnect(state);
+	    return;
+
+	case 0:
+	    if (command_resp(state, command_table, "connect", "") < 0)
+		disconnect(state);
+	    else if (command_table->delay == 0) {
+		event_enable_read(fd, read_event, (void *) state);
+		event_request_timer(read_timeout, (void *) state, var_tmout);
+	    }
+	}
+    }
+}
+
+/* usage - explain */
+
+static void usage(char *myname)
+{
+    msg_fatal("usage: %s [-468acCeEFLpPv] [-A abort_delay] [-b soft_bounce_reply] [-B hard_bounce_reply] [-d dump-template] [-D dump-template] [-f commands] [-h hostname] [-m max_concurrency] [-M message_quit_count] [-n quit_count] [-q commands] [-r commands] [-R root-dir] [-s commands] [-S start-string] [-u user_privs] [-w delay] [host]:port backlog", myname);
+}
+
+MAIL_VERSION_STAMP_DECLARE;
+
+int     main(int argc, char **argv)
+{
+    int     backlog;
+    int     ch;
+    int     delay;
+    const char *protocols = INET_PROTO_NAME_ALL;
+    const char *root_dir = 0;
+    const char *user_privs = 0;
+
+    /*
+     * Fingerprint executables and core dumps.
+     */
+    MAIL_VERSION_STAMP_ALLOCATE;
+
+    /*
+     * Fix 20051207.
+     */
+    signal(SIGPIPE, SIG_IGN);
+
+    /*
+     * Initialize diagnostics.
+     */
+    msg_vstream_init(argv[0], VSTREAM_ERR);
+
+    /*
+     * Parse JCL.
+     */
+    while ((ch = GETOPT(argc, argv, "468aA:b:B:cCd:D:eEf:Fh:H:Ln:m:M:NpPq:Q:r:R:s:S:t:T:u:vw:W:")) > 0) {
+	switch (ch) {
+	case '4':
+	    protocols = INET_PROTO_NAME_IPV4;
+	    break;
+	case '6':
+	    protocols = INET_PROTO_NAME_IPV6;
+	    break;
+	case '8':
+	    disable_8bitmime = 1;
+	    break;
+	case 'a':
+	    disable_saslauth = 1;
+	    break;
+	case 'A':
+	    if (!alldig(optarg) || (abort_delay = atoi(optarg)) < 0)
+		usage(argv[0]);
+	    break;
+	case 'b':
+	    if (optarg[0] != '4' || strspn(optarg, "0123456789") != 3) {
+		msg_error("bad soft error reply: %s", optarg);
+		usage(argv[0]);
+	    } else
+		soft_error_resp = optarg;
+	    break;
+	case 'B':
+	    if (optarg[0] != '5' || strspn(optarg, "0123456789") != 3) {
+		msg_error("bad hard error reply: %s", optarg);
+		usage(argv[0]);
+	    } else
+		hard_error_resp = optarg;
+	    break;
+	case 'c':
+	    show_count++;
+	    break;
+	case 'C':
+	    disable_xclient = 1;
+	    reset_cmd_flags("xclient", FLAG_ENABLE);
+	    break;
+	case 'd':
+	    single_template = optarg;
+	    break;
+	case 'D':
+	    shared_template = optarg;
+	    break;
+	case 'e':
+	    disable_esmtp = 1;
+	    break;
+	case 'E':
+	    disable_enh_status = 1;
+	    break;
+	case 'f':
+	    set_cmds_flags(optarg, FLAG_HARD_ERR);
+	    disable_pipelining = 1;
+	    break;
+	case 'F':
+	    disable_xforward = 1;
+	    reset_cmd_flags("xforward", FLAG_ENABLE);
+	    break;
+	case 'h':
+	    var_myhostname = optarg;
+	    break;
+	case 'H':
+	    if ((data_read_delay = atoi(optarg)) <= 0)
+		msg_fatal("bad data read delay: %s", optarg);
+	    break;
+	case 'L':
+	    enable_lmtp = 1;
+	    break;
+	case 'm':
+	    if ((max_client_count = atoi(optarg)) <= 0)
+		msg_fatal("bad concurrency limit: %s", optarg);
+	    break;
+	case 'M':
+	    if ((max_msg_quit_count = atoi(optarg)) <= 0)
+		msg_fatal("bad message quit count: %s", optarg);
+	    break;
+	case 'n':
+	    if ((max_quit_count = atoi(optarg)) <= 0)
+		msg_fatal("bad quit count: %s", optarg);
+	    break;
+	case 'N':
+	    disable_dsn = 1;
+	    break;
+	case 'p':
+	    disable_pipelining = 1;
+	    break;
+	case 'P':
+	    pretend_pix = 1;
+	    disable_esmtp = 1;
+	    break;
+	case 'q':
+	    set_cmds_flags(optarg, FLAG_DISCONNECT);
+	    break;
+	case 'Q':
+	    set_cmds_flags(optarg, FLAG_CLOSE);
+	    break;
+	case 'r':
+	    set_cmds_flags(optarg, FLAG_SOFT_ERR);
+	    disable_pipelining = 1;
+	    break;
+	case 'R':
+	    root_dir = optarg;
+	    break;
+	case 's':
+	    openlog(basename(argv[0]), LOG_PID, LOG_MAIL);
+	    set_cmds_flags(optarg, FLAG_SYSLOG);
+	    break;
+	case 'S':
+	    start_string = vstring_alloc(10);
+	    unescape(start_string, optarg);
+	    break;
+	case 't':
+	    if ((var_tmout = atoi(optarg)) <= 0)
+		msg_fatal("bad timeout: %s", optarg);
+	    break;
+	case 'T':
+	    if ((inet_windowsize = atoi(optarg)) <= 0)
+		msg_fatal("bad TCP window size: %s", optarg);
+	    break;
+	case 'u':
+	    user_privs = optarg;
+	    break;
+	case 'v':
+	    msg_verbose++;
+	    break;
+	case 'w':
+	    if ((delay = atoi(optarg)) <= 0)
+		usage(argv[0]);
+	    set_cmd_delay("data", delay, 0);
+	    break;
+	case 'W':
+	    set_cmd_delay_arg(optarg);
+	    break;
+	default:
+	    usage(argv[0]);
+	}
+    }
+    if (argc - optind != 2)
+	usage(argv[0]);
+    if ((backlog = atoi(argv[optind + 1])) <= 0)
+	usage(argv[0]);
+    if (single_template && shared_template)
+	msg_fatal("use only one of -d or -D, but not both");
+    if (geteuid() == 0 && user_privs == 0)
+	msg_fatal("-u option is required if running as root");
+
+    /*
+     * Initialize.
+     */
+    if (var_myhostname == 0)
+	var_myhostname = "smtp-sink";
+    set_cmds_flags(enable_lmtp ? "lhlo" :
+		   disable_esmtp ? "helo" :
+		   "helo, ehlo", FLAG_ENABLE);
+    proto_info = inet_proto_init("protocols", protocols);
+    if (strncmp(argv[optind], "unix:", 5) == 0) {
+	sock = unix_listen(argv[optind] + 5, backlog, BLOCKING);
+    } else {
+	if (strncmp(argv[optind], "inet:", 5) == 0)
+	    argv[optind] += 5;
+	sock = inet_listen(argv[optind], backlog, BLOCKING);
+    }
+    if (user_privs)
+	chroot_uid(root_dir, user_privs);
+
+    if (single_template)
+	mysrand((int) time((time_t *) 0));
+    else if (shared_template)
+	single_template = shared_template;
+
+    /*
+     * Start the event handler.
+     */
+    event_enable_read(sock, connect_event, (void *) 0);
+    for (;;)
+	event_loop(-1);
+}