bounce_log.c revision 1.2 
1/*	$NetBSD: bounce_log.c,v 1.2 2017/02/14 01:16:45 christos Exp $	*/
2
3/*++
4/* NAME
5/*	bounce_log 3
6/* SUMMARY
7/*	bounce file API
8/* SYNOPSIS
9/*	#include <bounce_log.h>
10/*
11/*	typedef struct {
12/* .in +4
13/*	    /* No public members. */
14/* .in -4
15/*	} BOUNCE_LOG;
16/*
17/*	BOUNCE_LOG *bounce_log_open(queue, id, flags, mode)
18/*	const char *queue;
19/*	const char *id;
20/*	int	flags;
21/*	mode_t	mode;
22/*
23/*	BOUNCE_LOG *bounce_log_read(bp, rcpt, dsn)
24/*	BOUNCE_LOG *bp;
25/*	RCPT_BUF *rcpt;
26/*	DSN_BUF *dsn;
27/*
28/*	void	bounce_log_rewind(bp)
29/*	BOUNCE_LOG *bp;
30/*
31/*	void	bounce_log_close(bp)
32/*	BOUNCE_LOG *bp;
33/* DESCRIPTION
34/*	This module implements a bounce/defer logfile API. Information
35/*	is sanitized for control and non-ASCII characters. Fields not
36/*	present in input are represented by empty strings.
37/*
38/*	bounce_log_open() opens the named bounce or defer logfile
39/*	and returns a handle that must be used for further access.
40/*	The result is a null pointer if the file cannot be opened.
41/*	The caller is expected to inspect the errno code and deal
42/*	with the problem.
43/*
44/*	bounce_log_read() reads the next record from the bounce or defer
45/*	logfile (skipping over and warning about malformed data)
46/*	and breaks out the recipient address, the recipient status
47/*	and the text that explains why the recipient was undeliverable.
48/*	bounce_log_read() returns a null pointer when no recipient was read,
49/*	otherwise it returns its argument.
50/*
51/*	bounce_log_rewind() is a helper that seeks to the first recipient
52/*	in an open bounce or defer logfile (skipping over recipients that
53/*	are marked as done). The result is 0 in case of success, -1 in case
54/*	of problems.
55/*
56/*	bounce_log_close() closes an open bounce or defer logfile and
57/*	releases memory for the specified handle. The result is non-zero
58/*	in case of I/O errors.
59/*
60/*	Arguments:
61/* .IP queue
62/*	The bounce or defer queue name.
63/* .IP id
64/*	The message queue id of bounce or defer logfile. This
65/*	file has the same name as the original message file.
66/* .IP flags
67/*	File open flags, as with open(2).
68/* .IP mode
69/*	File permissions, as with open(2).
70/* .IP rcpt
71/*	Recipient buffer. The RECIPIENT member is updated.
72/* .IP dsn
73/*	Delivery status information. The DSN member is updated.
74/* LICENSE
75/* .ad
76/* .fi
77/*	The Secure Mailer license must be distributed with this software.
78/* AUTHOR(S)
79/*	Wietse Venema
80/*	IBM T.J. Watson Research
81/*	P.O. Box 704
82/*	Yorktown Heights, NY 10598, USA
83/*--*/
84
85/* System library. */
86
87#include <sys_defs.h>
88#include <string.h>
89#include <ctype.h>
90#include <unistd.h>
91#include <stdlib.h>
92
93/* Utility library. */
94
95#include <msg.h>
96#include <mymalloc.h>
97#include <vstream.h>
98#include <vstring.h>
99#include <vstring_vstream.h>
100#include <stringops.h>
101
102/* Global library. */
103
104#include <mail_params.h>
105#include <mail_proto.h>
106#include <mail_queue.h>
107#include <dsn_mask.h>
108#include <bounce_log.h>
109
110/* Application-specific. */
111
112#define STR(x)		vstring_str(x)
113
114/* bounce_log_open - open bounce read stream */
115
116BOUNCE_LOG *bounce_log_open(const char *queue_name, const char *queue_id,
117			            int flags, mode_t mode)
118{
119    BOUNCE_LOG *bp;
120    VSTREAM *fp;
121
122#define STREQ(x,y)	(strcmp((x),(y)) == 0)
123
124    /*
125     * Logfiles may contain a mixture of old-style (<recipient>: text) and
126     * new-style entries with multiple attributes per recipient.
127     *
128     * Kluge up default DSN status and action for old-style logfiles.
129     */
130    if ((fp = mail_queue_open(queue_name, queue_id, flags, mode)) == 0) {
131	return (0);
132    } else {
133	bp = (BOUNCE_LOG *) mymalloc(sizeof(*bp));
134	bp->fp = fp;
135	bp->buf = vstring_alloc(100);
136	if (STREQ(queue_name, MAIL_QUEUE_DEFER)) {
137	    bp->compat_status = mystrdup("4.0.0");
138	    bp->compat_action = mystrdup("delayed");
139	} else {
140	    bp->compat_status = mystrdup("5.0.0");
141	    bp->compat_action = mystrdup("failed");
142	}
143	return (bp);
144    }
145}
146
147/* bounce_log_read - read one record from bounce log file */
148
149BOUNCE_LOG *bounce_log_read(BOUNCE_LOG *bp, RCPT_BUF *rcpt_buf,
150			            DSN_BUF *dsn_buf)
151{
152    char   *recipient;
153    char   *text;
154    char   *cp;
155    int     state;
156
157    /*
158     * Our trivial logfile parser state machine.
159     */
160#define START	0				/* still searching */
161#define FOUND	1				/* in logfile entry */
162
163    /*
164     * Initialize.
165     */
166    state = START;
167    rcpb_reset(rcpt_buf);
168    dsb_reset(dsn_buf);
169
170    /*
171     * Support mixed logfile formats to make migration easier. The same file
172     * can start with old-style records and end with new-style records. With
173     * backwards compatibility, we even have old format followed by new
174     * format within the same logfile entry!
175     */
176    for (;;) {
177	if ((vstring_get_nonl(bp->buf, bp->fp) == VSTREAM_EOF))
178	    return (0);
179
180	/*
181	 * Logfile entries are separated by blank lines. Even the old ad-hoc
182	 * logfile format has a blank line after the last record. This means
183	 * we can safely use blank lines to detect the start and end of
184	 * logfile entries.
185	 */
186	if (STR(bp->buf)[0] == 0) {
187	    if (state == FOUND)
188		break;
189	    state = START;
190	    continue;
191	}
192
193	/*
194	 * Sanitize. XXX This needs to be done more carefully with new-style
195	 * logfile entries.
196	 */
197	cp = printable(STR(bp->buf), '?');
198
199	if (state == START)
200	    state = FOUND;
201
202	/*
203	 * New style logfile entries are in "name = value" format.
204	 */
205	if (ISALNUM(*cp)) {
206	    const char *err;
207	    char   *name;
208	    char   *value;
209	    long    offset;
210	    int     notify;
211
212	    /*
213	     * Split into name and value.
214	     */
215	    if ((err = split_nameval(cp, &name, &value)) != 0) {
216		msg_warn("%s: malformed record: %s", VSTREAM_PATH(bp->fp), err);
217		continue;
218	    }
219
220	    /*
221	     * Save attribute value.
222	     */
223	    if (STREQ(name, MAIL_ATTR_RECIP)) {
224		vstring_strcpy(rcpt_buf->address, *value ?
225			       value : "(MAILER-DAEMON)");
226	    } else if (STREQ(name, MAIL_ATTR_ORCPT)) {
227		vstring_strcpy(rcpt_buf->orig_addr, *value ?
228			       value : "(MAILER-DAEMON)");
229	    } else if (STREQ(name, MAIL_ATTR_DSN_ORCPT)) {
230		vstring_strcpy(rcpt_buf->dsn_orcpt, value);
231	    } else if (STREQ(name, MAIL_ATTR_DSN_NOTIFY)) {
232		if ((notify = atoi(value)) > 0 && DSN_NOTIFY_OK(notify))
233		    rcpt_buf->dsn_notify = notify;
234	    } else if (STREQ(name, MAIL_ATTR_OFFSET)) {
235		if ((offset = atol(value)) > 0)
236		    rcpt_buf->offset = offset;
237	    } else if (STREQ(name, MAIL_ATTR_DSN_STATUS)) {
238		vstring_strcpy(dsn_buf->status, value);
239	    } else if (STREQ(name, MAIL_ATTR_DSN_ACTION)) {
240		vstring_strcpy(dsn_buf->action, value);
241	    } else if (STREQ(name, MAIL_ATTR_DSN_DTYPE)) {
242		vstring_strcpy(dsn_buf->dtype, value);
243	    } else if (STREQ(name, MAIL_ATTR_DSN_DTEXT)) {
244		vstring_strcpy(dsn_buf->dtext, value);
245	    } else if (STREQ(name, MAIL_ATTR_DSN_MTYPE)) {
246		vstring_strcpy(dsn_buf->mtype, value);
247	    } else if (STREQ(name, MAIL_ATTR_DSN_MNAME)) {
248		vstring_strcpy(dsn_buf->mname, value);
249	    } else if (STREQ(name, MAIL_ATTR_WHY)) {
250		vstring_strcpy(dsn_buf->reason, value);
251	    } else {
252		msg_warn("%s: unknown attribute name: %s, ignored",
253			 VSTREAM_PATH(bp->fp), name);
254	    }
255	    continue;
256	}
257
258	/*
259	 * Old-style logfile record. Find the recipient address.
260	 */
261	if (*cp != '<') {
262	    msg_warn("%s: malformed record: %.30s...",
263		     VSTREAM_PATH(bp->fp), cp);
264	    continue;
265	}
266	recipient = cp + 1;
267	if ((cp = strstr(recipient, ">: ")) == 0) {
268	    msg_warn("%s: malformed record: %.30s...",
269		     VSTREAM_PATH(bp->fp), cp);
270	    continue;
271	}
272	*cp = 0;
273	vstring_strcpy(rcpt_buf->address, *recipient ?
274		       recipient : "(MAILER-DAEMON)");
275
276	/*
277	 * Find the text that explains why mail was not deliverable.
278	 */
279	text = cp + 2;
280	while (*text && ISSPACE(*text))
281	    text++;
282	vstring_strcpy(dsn_buf->reason, text);
283    }
284
285    /*
286     * Specify place holders for missing fields. See also DSN_FROM_DSN_BUF()
287     * and RECIPIENT_FROM_RCPT_BUF() for null and non-null fields.
288     */
289#define BUF_NODATA(buf)		(STR(buf)[0] == 0)
290#define BUF_ASSIGN(buf, text)	vstring_strcpy((buf), (text))
291
292    if (BUF_NODATA(rcpt_buf->address))
293	BUF_ASSIGN(rcpt_buf->address, "(recipient address unavailable)");
294    if (BUF_NODATA(dsn_buf->status))
295	BUF_ASSIGN(dsn_buf->status, bp->compat_status);
296    if (BUF_NODATA(dsn_buf->action))
297	BUF_ASSIGN(dsn_buf->action, bp->compat_action);
298    if (BUF_NODATA(dsn_buf->reason))
299	BUF_ASSIGN(dsn_buf->reason, "(description unavailable)");
300    (void) RECIPIENT_FROM_RCPT_BUF(rcpt_buf);
301    (void) DSN_FROM_DSN_BUF(dsn_buf);
302    return (bp);
303}
304
305/* bounce_log_close - close bounce reader stream */
306
307int     bounce_log_close(BOUNCE_LOG *bp)
308{
309    int     ret;
310
311    ret = vstream_fclose(bp->fp);
312    vstring_free(bp->buf);
313    myfree(bp->compat_status);
314    myfree(bp->compat_action);
315    myfree((void *) bp);
316
317    return (ret);
318}
319