1 /*        $NetBSD: bounce_templates.c,v 1.3 2022/10/08 16:12:45 christos Exp $  */
2 
3 /*++
4 /* NAME
5 /*        bounce_templates 3
6 /* SUMMARY
7 /*        bounce template group support
8 /* SYNOPSIS
9 /*        #include <bounce_template.h>
10 /*
11 /*        typedef struct {
12 /* .in +4
13 /*                  BOUNCE_TEMPLATE *failure;
14 /*                  BOUNCE_TEMPLATE *delay;
15 /*                  BOUNCE_TEMPLATE *success;
16 /*                  BOUNCE_TEMPLATE *verify;
17 /* .in -4
18 /*        } BOUNCE_TEMPLATES;
19 /*
20 /*        BOUNCE_TEMPLATES *bounce_templates_create(void)
21 /*
22 /*        void      bounce_templates_free(templates)
23 /*        BOUNCE_TEMPLATES *templates;
24 /*
25 /*        void      bounce_templates_load(stream, templates)
26 /*        VSTREAM   *stream;
27 /*        BOUNCE_TEMPLATES *templates;
28 /*
29 /*        void      bounce_templates_expand(stream, templates)
30 /*        VSTREAM   *stream;
31 /*        BOUNCE_TEMPLATES *templates;
32 /*
33 /*        void      bounce_templates_dump(stream, templates)
34 /*        VSTREAM   *stream;
35 /*        BOUNCE_TEMPLATES *templates;
36 /* DESCRIPTION
37 /*        This module implements support for bounce template groups
38 /*        (i.e. groups that contain one template of each type).
39 /*
40 /*        bounce_templates_create() creates a bounce template group,
41 /*        with default settings.
42 /*
43 /*        bounce_templates_free() destroys a bounce template group.
44 /*
45 /*        bounce_templates_load() reads zero or more bounce templates
46 /*        from the specified file to override built-in templates.
47 /*
48 /*        bounce_templates_expand() expands $name macros and writes
49 /*        the text portions of the specified bounce template group
50 /*        to the specified stream.
51 /*
52 /*        bounce_templates_dump() writes the complete content of the
53 /*        specified bounce template group to the specified stream.
54 /*        The format is compatible with bounce_templates_load().
55 /* DIAGNOSTICS
56 /*        Fatal error: out of memory, undefined macro name in template.
57 /* SEE ALSO
58 /*        bounce_template(3) bounce template support
59 /* LICENSE
60 /* .ad
61 /* .fi
62 /*        The Secure Mailer license must be distributed with this software.
63 /* AUTHOR(S)
64 /*        Wietse Venema
65 /*        IBM T.J. Watson Research
66 /*        P.O. Box 704
67 /*        Yorktown Heights, NY 10598, USA
68 /*
69 /*        Wietse Venema
70 /*        Google, Inc.
71 /*        111 8th Avenue
72 /*        New York, NY 10011, USA
73 /*--*/
74 
75 /* System library. */
76 
77 #include <sys_defs.h>
78 #include <ctype.h>
79 #include <string.h>
80 
81 /* Utility library. */
82 
83 #include <msg.h>
84 #include <mymalloc.h>
85 #include <stringops.h>
86 #include <vstring.h>
87 #include <vstream.h>
88 #include <vstring_vstream.h>
89 
90 /* Global library. */
91 
92 #include <mail_addr.h>
93 #include <mail_proto.h>
94 
95 /* Application-specific. */
96 
97 #include <bounce_template.h>
98 
99  /*
100   * The fail template is for permanent failure.
101   */
102 static const char *def_bounce_failure_body[] = {
103     "This is the mail system at host $myhostname.",
104     "",
105     "I'm sorry to have to inform you that your message could not",
106     "be delivered to one or more recipients. It's attached below.",
107     "",
108     "For further assistance, please send mail to " MAIL_ADDR_POSTMASTER ".",
109     "",
110     "If you do so, please include this problem report. You can",
111     "delete your own text from the attached returned message.",
112     "",
113     "                   The mail system",
114     0,
115 };
116 
117 static const BOUNCE_TEMPLATE def_bounce_failure_template = {
118     0,
119     BOUNCE_TMPL_CLASS_FAILURE,
120     "[built-in]",
121     "us-ascii",
122     MAIL_ATTR_ENC_7BIT,
123     MAIL_ADDR_MAIL_DAEMON " (Mail Delivery System)",
124     "Mail Delivery System <" MAIL_ADDR_MAIL_DAEMON ">",
125     "Undelivered Mail Returned to Sender",
126     "Postmaster Copy: Undelivered Mail",
127     def_bounce_failure_body,
128     &def_bounce_failure_template,
129 };
130 
131  /*
132   * The delay template is for delayed mail notifications.
133   */
134 static const char *def_bounce_delay_body[] = {
135     "This is the mail system at host $myhostname.",
136     "",
137     "####################################################################",
138     "# THIS IS A WARNING ONLY.  YOU DO NOT NEED TO RESEND YOUR MESSAGE. #",
139     "####################################################################",
140     "",
141     "Your message could not be delivered for more than $delay_warning_time_hours hour(s).",
142     "It will be retried until it is $maximal_queue_lifetime_days day(s) old.",
143     "",
144     "For further assistance, please send mail to " MAIL_ADDR_POSTMASTER ".",
145     "",
146     "If you do so, please include this problem report. You can",
147     "delete your own text from the attached returned message.",
148     "",
149     "                   The mail system",
150     0,
151 };
152 
153 static const BOUNCE_TEMPLATE def_bounce_delay_template = {
154     0,
155     BOUNCE_TMPL_CLASS_DELAY,
156     "[built-in]",
157     "us-ascii",
158     MAIL_ATTR_ENC_7BIT,
159     MAIL_ADDR_MAIL_DAEMON " (Mail Delivery System)",
160     "Mail Delivery System <" MAIL_ADDR_MAIL_DAEMON ">",
161     "Delayed Mail (still being retried)",
162     "Postmaster Warning: Delayed Mail",
163     def_bounce_delay_body,
164     &def_bounce_delay_template
165 };
166 
167  /*
168   * The success template is for "delivered", "expanded" and "relayed" success
169   * notifications.
170   */
171 static const char *def_bounce_success_body[] = {
172     "This is the mail system at host $myhostname.",
173     "",
174     "Your message was successfully delivered to the destination(s)",
175     "listed below. If the message was delivered to mailbox you will",
176     "receive no further notifications. Otherwise you may still receive",
177     "notifications of mail delivery errors from other systems.",
178     "",
179     "                   The mail system",
180     0,
181 };
182 
183 static const BOUNCE_TEMPLATE def_bounce_success_template = {
184     0,
185     BOUNCE_TMPL_CLASS_SUCCESS,
186     "[built-in]",
187     "us-ascii",
188     MAIL_ATTR_ENC_7BIT,
189     MAIL_ADDR_MAIL_DAEMON " (Mail Delivery System)",
190     "Mail Delivery System <" MAIL_ADDR_MAIL_DAEMON ">",
191     "Successful Mail Delivery Report",
192     0,
193     def_bounce_success_body,
194     &def_bounce_success_template,
195 };
196 
197  /*
198   * The "verify" template is for verbose delivery (sendmail -v) and for
199   * address verification (sendmail -bv).
200   */
201 static const char *def_bounce_verify_body[] = {
202     "This is the mail system at host $myhostname.",
203     "",
204     "Enclosed is the mail delivery report that you requested.",
205     "",
206     "                   The mail system",
207     0,
208 };
209 
210 static const BOUNCE_TEMPLATE def_bounce_verify_template = {
211     0,
212     BOUNCE_TMPL_CLASS_VERIFY,
213     "[built-in]",
214     "us-ascii",
215     MAIL_ATTR_ENC_7BIT,
216     MAIL_ADDR_MAIL_DAEMON " (Mail Delivery System)",
217     "Mail Delivery System <" MAIL_ADDR_MAIL_DAEMON ">",
218     "Mail Delivery Status Report",
219     0,
220     def_bounce_verify_body,
221     &def_bounce_verify_template,
222 };
223 
224  /*
225   * SLMs.
226   */
227 #define STR(x)      vstring_str(x)
228 
229 /* bounce_templates_create - create template group */
230 
bounce_templates_create(void)231 BOUNCE_TEMPLATES *bounce_templates_create(void)
232 {
233     BOUNCE_TEMPLATES *bs;
234 
235     bs = (BOUNCE_TEMPLATES *) mymalloc(sizeof(*bs));
236     bs->failure = bounce_template_create(&def_bounce_failure_template);
237     bs->delay = bounce_template_create(&def_bounce_delay_template);
238     bs->success = bounce_template_create(&def_bounce_success_template);
239     bs->verify = bounce_template_create(&def_bounce_verify_template);
240     return (bs);
241 }
242 
243 /* bounce_templates_free - destroy template group */
244 
bounce_templates_free(BOUNCE_TEMPLATES * bs)245 void    bounce_templates_free(BOUNCE_TEMPLATES *bs)
246 {
247     bounce_template_free(bs->failure);
248     bounce_template_free(bs->delay);
249     bounce_template_free(bs->success);
250     bounce_template_free(bs->verify);
251     myfree((void *) bs);
252 }
253 
254 /* bounce_templates_load - load template or group from stream */
255 
bounce_templates_load(VSTREAM * fp,BOUNCE_TEMPLATES * ts)256 void    bounce_templates_load(VSTREAM *fp, BOUNCE_TEMPLATES *ts)
257 {
258     VSTRING *line_buf;
259     char   *member_name;
260     VSTRING *multi_line_buf = 0;
261     VSTRING *saved_member_name = 0;
262     VSTRING *saved_end_marker = 0;
263     char   *value;
264     int     lineno;
265     const char *err;
266     char   *cp;
267     int     len;                        /* Grr... */
268 
269     /*
270      * XXX That's a lot of non-reusable code to parse a configuration file.
271      * Unfortunately, much of the "name = value" infrastructure is married to
272      * the dict(3) class which doesn't really help here.
273      */
274     line_buf = vstring_alloc(100);
275     lineno = 1;
276     while (vstring_get_nonl(line_buf, fp) > 0) {
277           lineno++;
278           cp = STR(line_buf) + strspn(STR(line_buf), " \t\n\v\f\r");
279           if (*cp == 0 || *cp == '#')
280               continue;
281           if ((err = split_nameval(STR(line_buf), &member_name, &value)) != 0)
282               msg_fatal("%s, line %d: %s: \"%s\"",
283                           VSTREAM_PATH(fp), lineno, err, STR(line_buf));
284           if (value[0] == '<' && value[1] == '<') {
285               value += 2;
286               while (ISSPACE(*value))
287                     value++;
288               if (*value == 0)
289                     msg_fatal("%s, line %d: missing end marker after <<",
290                                 VSTREAM_PATH(fp), lineno);
291               if (!ISALNUM(*value))
292                     msg_fatal("%s, line %d: malformed end marker after <<",
293                                 VSTREAM_PATH(fp), lineno);
294               if (multi_line_buf == 0) {
295                     saved_member_name = vstring_alloc(100);
296                     saved_end_marker = vstring_alloc(100);
297                     multi_line_buf = vstring_alloc(100);
298               } else
299                     VSTRING_RESET(multi_line_buf);
300               vstring_strcpy(saved_member_name, member_name);
301               vstring_strcpy(saved_end_marker, value);
302               while (vstring_get_nonl(line_buf, fp) > 0) {
303                     lineno++;
304                     if (strcmp(STR(line_buf), STR(saved_end_marker)) == 0)
305                         break;
306                     if (VSTRING_LEN(multi_line_buf) > 0)
307                         vstring_strcat(multi_line_buf, "\n");
308                     vstring_strcat(multi_line_buf, STR(line_buf));
309               }
310               if (vstream_feof(fp))
311                     msg_warn("%s, line %d: missing \"%s\" end marker",
312                                VSTREAM_PATH(fp), lineno, value);
313               member_name = STR(saved_member_name);
314               value = STR(multi_line_buf);
315           }
316 #define MATCH_TMPL_NAME(tname, tname_len, mname) \
317     (strncmp(tname, mname, tname_len = strlen(tname)) == 0 \
318           && strcmp(mname + tname_len, "_template") == 0)
319 
320           if (MATCH_TMPL_NAME(ts->failure->class, len, member_name))
321               bounce_template_load(ts->failure, VSTREAM_PATH(fp), value);
322           else if (MATCH_TMPL_NAME(ts->delay->class, len, member_name))
323               bounce_template_load(ts->delay, VSTREAM_PATH(fp), value);
324           else if (MATCH_TMPL_NAME(ts->success->class, len, member_name))
325               bounce_template_load(ts->success, VSTREAM_PATH(fp), value);
326           else if (MATCH_TMPL_NAME(ts->verify->class, len, member_name))
327               bounce_template_load(ts->verify, VSTREAM_PATH(fp), value);
328           else
329               msg_warn("%s, line %d: unknown template name: %s "
330                          "-- ignoring this template",
331                          VSTREAM_PATH(fp), lineno, member_name);
332     }
333     vstring_free(line_buf);
334     if (multi_line_buf) {
335           vstring_free(saved_member_name);
336           vstring_free(saved_end_marker);
337           vstring_free(multi_line_buf);
338     }
339 }
340 
341 /* bounce_plain_out - output line as plain text */
342 
bounce_plain_out(VSTREAM * fp,const char * text)343 static int bounce_plain_out(VSTREAM *fp, const char *text)
344 {
345     vstream_fprintf(fp, "%s\n", text);
346     return (0);
347 }
348 
349 /* bounce_templates_expand - dump expanded template group text to stream */
350 
bounce_templates_expand(VSTREAM * fp,BOUNCE_TEMPLATES * ts)351 void    bounce_templates_expand(VSTREAM *fp, BOUNCE_TEMPLATES *ts)
352 {
353     BOUNCE_TEMPLATE *tp;
354 
355     tp = ts->failure;
356     vstream_fprintf(fp, "expanded_%s_text = <<EOF\n", tp->class);
357     bounce_template_expand(bounce_plain_out, fp, tp);
358     vstream_fprintf(fp, "EOF\n\n");
359 
360     tp = ts->delay;
361     vstream_fprintf(fp, "expanded_%s_text = <<EOF\n", tp->class);
362     bounce_template_expand(bounce_plain_out, fp, tp);
363     vstream_fprintf(fp, "EOF\n\n");
364 
365     tp = ts->success;
366     vstream_fprintf(fp, "expanded_%s_text = <<EOF\n", tp->class);
367     bounce_template_expand(bounce_plain_out, fp, tp);
368     vstream_fprintf(fp, "EOF\n\n");
369 
370     tp = ts->verify;
371     vstream_fprintf(fp, "expanded_%s_text = <<EOF\n", tp->class);
372     bounce_template_expand(bounce_plain_out, fp, tp);
373     vstream_fprintf(fp, "EOF\n");
374 }
375 
376 /* bounce_templates_dump - dump bounce template group to stream */
377 
bounce_templates_dump(VSTREAM * fp,BOUNCE_TEMPLATES * ts)378 void    bounce_templates_dump(VSTREAM *fp, BOUNCE_TEMPLATES *ts)
379 {
380     BOUNCE_TEMPLATE *tp;
381 
382     tp = ts->failure;
383     vstream_fprintf(fp, "%s_template = <<EOF\n", tp->class);
384     bounce_template_dump(fp, tp);
385     vstream_fprintf(fp, "EOF\n\n");
386 
387     tp = ts->delay;
388     vstream_fprintf(fp, "%s_template = <<EOF\n", tp->class);
389     bounce_template_dump(fp, tp);
390     vstream_fprintf(fp, "EOF\n\n");
391 
392     tp = ts->success;
393     vstream_fprintf(fp, "%s_template = <<EOF\n", tp->class);
394     bounce_template_dump(fp, tp);
395     vstream_fprintf(fp, "EOF\n\n");
396 
397     tp = ts->verify;
398     vstream_fprintf(fp, "%s_template = <<EOF\n", tp->class);
399     bounce_template_dump(fp, tp);
400     vstream_fprintf(fp, "EOF\n");
401 }
402