1/*	$NetBSD: bounce_trace_service.c,v 1.2 2017/02/14 01:16:44 christos Exp $	*/
2
3/*++
4/* NAME
5/*	bounce_trace_service 3
6/* SUMMARY
7/*	send status report to sender, server side
8/* SYNOPSIS
9/*	#include "bounce_service.h"
10/*
11/*	int     bounce_trace_service(flags, service, queue_name, queue_id,
12/*					encoding, smtputf8, sender, envid,
13/*					ret, templates)
14/*	int	flags;
15/*	char	*service;
16/*	char	*queue_name;
17/*	char	*queue_id;
18/*	char	*encoding;
19/*	int	smtputf8;
20/*	char	*sender;
21/*	char	*envid;
22/*	int	ret;
23/*	BOUNCE_TEMPLATES *templates;
24/* DESCRIPTION
25/*	This module implements the server side of the trace_flush()
26/*	(send delivery notice) request. The logfile
27/*	is removed after the notice is posted.
28/*
29/*	A status report includes a prelude with human-readable text,
30/*	a DSN-style report, and the email message that was subject of
31/*	the status report.
32/*
33/*	When a status report is sent, the sender address is the empty
34/*	address.
35/* DIAGNOSTICS
36/*	Fatal error: error opening existing file.
37/* BUGS
38/* SEE ALSO
39/*	bounce(3) basic bounce service client interface
40/* LICENSE
41/* .ad
42/* .fi
43/*	The Secure Mailer license must be distributed with this software.
44/* AUTHOR(S)
45/*	Wietse Venema
46/*	IBM T.J. Watson Research
47/*	P.O. Box 704
48/*	Yorktown Heights, NY 10598, USA
49/*--*/
50
51/* System library. */
52
53#include <sys_defs.h>
54#include <fcntl.h>
55#include <errno.h>
56#include <string.h>
57#include <ctype.h>
58
59/* Utility library. */
60
61#include <msg.h>
62#include <vstream.h>
63#include <stringops.h>
64
65/* Global library. */
66
67#include <mail_params.h>
68#include <mail_queue.h>
69#include <post_mail.h>
70#include <mail_addr.h>
71#include <mail_error.h>
72#include <dsn_mask.h>
73#include <rec_type.h>
74#include <deliver_request.h>		/* USR_VRFY and RECORD flags */
75
76/* Application-specific. */
77
78#include "bounce_service.h"
79
80#define STR vstring_str
81
82/* bounce_trace_service - send a delivery status notice */
83
84int     bounce_trace_service(int flags, char *service, char *queue_name,
85			             char *queue_id, char *encoding,
86			             int smtputf8,
87			             char *recipient, char *dsn_envid,
88			             int unused_dsn_ret,
89			             BOUNCE_TEMPLATES *ts)
90{
91    BOUNCE_INFO *bounce_info;
92    int     bounce_status = 1;
93    VSTREAM *bounce;
94    int     notify_mask = name_mask(VAR_NOTIFY_CLASSES, mail_error_masks,
95				    var_notify_classes);
96    VSTRING *new_id;
97    int     count;
98    const char *sender;
99
100    /*
101     * For consistency with fail/delay notifications, send notification for a
102     * non-bounce message as a single-bounce message, send notification for a
103     * single-bounce message as a double-bounce message, and drop requests to
104     * send notification for a double-bounce message.
105     */
106#define NULL_SENDER		MAIL_ADDR_EMPTY	/* special address */
107
108    if (strcasecmp_utf8(recipient, mail_addr_double_bounce()) == 0) {
109	msg_info("%s: not sending trace/success notification for "
110		 "double-bounce message", queue_id);
111	return (0);
112    } else if (*recipient == 0) {
113	if ((notify_mask & MAIL_ERROR_2BOUNCE) != 0) {
114	    recipient = var_2bounce_rcpt;
115	    sender = mail_addr_double_bounce();
116	} else {
117	    msg_info("%s: not sending trace/success notification "
118		     "for single-bounce message", queue_id);
119	    if (mail_queue_remove(service, queue_id) && errno != ENOENT)
120		msg_fatal("remove %s %s: %m", service, queue_id);
121	    return (0);
122	}
123    } else {
124	/* Always send notification for non-bounce message. */
125	sender = NULL_SENDER;
126    }
127
128    /*
129     * Initialize. Open queue file, bounce log, etc.
130     *
131     * XXX DSN The trace service produces information from the trace logfile
132     * which is used for three types of reports:
133     *
134     * a) "what-if" reports that show what would happen without actually
135     * delivering mail (sendmail -bv).
136     *
137     * b) A report of actual deliveries (sendmail -v).
138     *
139     * c) DSN NOTIFY=SUCCESS reports of successful delivery ("delivered",
140     * "expanded" or "relayed").
141     */
142#define NON_DSN_FLAGS (DEL_REQ_FLAG_USR_VRFY | DEL_REQ_FLAG_RECORD)
143
144    bounce_info = bounce_mail_init(service, queue_name, queue_id,
145				   encoding, smtputf8, dsn_envid,
146				   flags & NON_DSN_FLAGS ?
147				   ts->verify : ts->success);
148
149    /*
150     * XXX With multi-recipient mail some queue file recipients may have
151     * NOTIFY=SUCCESS and others not. Depending on what subset of recipients
152     * are delivered, a trace file may or may not be created. Even when the
153     * last partial delivery attempt had no NOTIFY=SUCCESS recipients, a
154     * trace file may still exist from a previous partial delivery attempt.
155     * So as long as any recipient in the original queue file had
156     * NOTIFY=SUCCESS we have to always look for the trace file and be
157     * prepared for the file not to exist.
158     *
159     * See also comments in qmgr/qmgr_active.c.
160     */
161    if (bounce_info->log_handle == 0) {
162	if (msg_verbose)
163	    msg_info("%s: no trace file -- not sending a notification",
164		     queue_id);
165	bounce_mail_free(bounce_info);
166	return (0);
167    }
168#define NULL_TRACE_FLAGS	0
169
170    /*
171     * Send a single bounce with a template message header, some boilerplate
172     * text that pretends that we are a polite mail system, the text with
173     * per-recipient status, and a copy of the original message.
174     *
175     * XXX DSN We use the same trace file for "what-if", "verbose delivery" and
176     * "success" delivery reports. This saves file system overhead because
177     * there are fewer potential left-over files to remove up when we create
178     * a new queue file.
179     */
180    new_id = vstring_alloc(10);
181    if ((bounce = post_mail_fopen_nowait(sender, recipient,
182					 MAIL_SRC_MASK_BOUNCE,
183					 NULL_TRACE_FLAGS,
184					 smtputf8,
185					 new_id)) != 0) {
186	count = -1;
187	if (bounce_header(bounce, bounce_info, recipient,
188			  NO_POSTMASTER_COPY) == 0
189	    && bounce_boilerplate(bounce, bounce_info) == 0
190	    && (count = bounce_diagnostic_log(bounce, bounce_info,
191					      DSN_NOTIFY_OVERRIDE)) > 0
192	    && bounce_header_dsn(bounce, bounce_info) == 0
193	    && bounce_diagnostic_dsn(bounce, bounce_info,
194				     DSN_NOTIFY_OVERRIDE) > 0) {
195	    bounce_original(bounce, bounce_info, DSN_RET_HDRS);
196	    bounce_status = post_mail_fclose(bounce);
197	    if (bounce_status == 0)
198		msg_info("%s: sender delivery status notification: %s",
199			 queue_id, STR(new_id));
200	} else {
201	    (void) vstream_fclose(bounce);
202	    if (count == 0)
203		bounce_status = 0;
204	}
205    }
206
207    /*
208     * Examine the completion status. Delete the trace log file only when the
209     * status notice was posted successfully.
210     */
211    if (bounce_status == 0 && mail_queue_remove(service, queue_id)
212	&& errno != ENOENT)
213	msg_fatal("remove %s %s: %m", service, queue_id);
214
215    /*
216     * Cleanup.
217     */
218    bounce_mail_free(bounce_info);
219    vstring_free(new_id);
220
221    return (bounce_status);
222}
223