1 /*++
2 /* NAME
3 /*	dsn_buf 3
4 /* SUMMARY
5 /*	delivery status buffer
6 /* SYNOPSIS
7 /*	#include <dsn_buf.h>
8 /*
9 /*	typedef struct {
10 /* .in +4
11 /*		/* Convenience member */
12 /*		DSN	dsn;		/* light-weight, dsn(3) */
13 /*		/* Formal members... */
14 /*		VSTRING *status;	/* RFC 3463 */
15 /*		VSTRING *action;	/* RFC 3464 */
16 /*		VSTRING	*mtype;		/* dns */
17 /*		VSTRING	*mname;		/* host or domain */
18 /*		VSTRING	*dtype;		/* smtp, x-unix */
19 /*		VSTRING *dtext;		/* RFC 2821, sysexits.h */
20 /*		/* Informal members... */
21 /*		VSTRING	*reason;	/* informal text */
22 /* .in -4
23 /*	} DSN_BUF;
24 /*
25 /*	DSN_BUF	*dsb_create(void)
26 /*
27 /*	DSN_BUF	*dsb_update(dsb, status, action, mtype, mname, dtype,
28 /*				dtext, reason_fmt, ...)
29 /*	DSN_BUF	*dsb;
30 /*	const char *status;
31 /*	const char *action;
32 /*	const char *mtype;
33 /*	const char *mname;
34 /*	const char *dtype;
35 /*	const char *dtext;
36 /*	const char *reason_fmt;
37 /*
38 /*	DSN_BUF	*dsb_simple(dsb, status, reason_fmt, ...)
39 /*	DSN_BUF	*dsb;
40 /*	const char *status;
41 /*	const char *reason_fmt;
42 /*
43 /*	DSN_BUF	*dsb_unix(dsb, status, dtext, reason_fmt, ...)
44 /*	DSN_BUF	*dsb;
45 /*	const char *status;
46 /*	const char *reason_fmt;
47 /*
48 /*	DSN_BUF	*dsb_formal(dsb, status, action, mtype, mname, dtype,
49 /*				dtext)
50 /*	DSN_BUF	*dsb;
51 /*	const char *status;
52 /*	const char *action;
53 /*	const char *mtype;
54 /*	const char *mname;
55 /*	const char *dtype;
56 /*	const char *dtext;
57 /*
58 /*	DSN_BUF	*dsb_status(dsb, status)
59 /*	DSN_BUF	*dsb;
60 /*	const char *status;
61 /*
62 /*	void	dsb_reset(dsb)
63 /*	DSN_BUF	*dsb;
64 /*
65 /*	void	dsb_free(dsb)
66 /*	DSN_BUF	*dsb;
67 /*
68 /*	DSN	*DSN_FROM_DSN_BUF(dsb)
69 /*	DSN_BUF	*dsb;
70 /* DESCRIPTION
71 /*	This module implements a simple to update delivery status
72 /*	buffer for Postfix-internal use. Typically it is filled in
73 /*	the course of delivery attempt, and then formatted into a
74 /*	DSN structure for external notification.
75 /*
76 /*	dsb_create() creates initialized storage for formal RFC 3464
77 /*	attributes, and human-readable informal text.
78 /*
79 /*	dsb_update() updates all fields.
80 /*
81 /*	dsb_simple() updates the status and informal text, and resets all
82 /*	other fields to defaults.
83 /*
84 /*	dsb_unix() updates the status, diagnostic code, diagnostic
85 /*	text, and informal text, sets the diagnostic type to UNIX,
86 /*	and resets all other fields to defaults.
87 /*
88 /*	dsb_formal() updates all fields except the informal text.
89 /*
90 /*	dsb_status() updates the status field, and resets all
91 /*	formal fields to defaults.
92 /*
93 /*	dsb_reset() resets all fields in a DSN_BUF structure without
94 /*	deallocating memory.
95 /*
96 /*	dsb_free() recycles the storage that was allocated by
97 /*	dsb_create(), and so on.
98 /*
99 /*	DSN_FROM_DSN_BUF() populates the DSN member with a shallow
100 /*	copy of the contents of the formal and informal fields, and
101 /*	returns a pointer to the DSN member. This is typically used
102 /*	for external reporting.
103 /*
104 /*	Arguments:
105 /* .IP dsb
106 /*	Delivery status buffer.
107 /* .IP status
108 /*	RFC 3463 "enhanced" status code.
109 /* .IP action
110 /*	RFC 3464 action code; specify DSB_DEF_ACTION to derive the
111 /*	action from the status value. The only values that really
112 /*	matter here are "expanded" and "relayed"; all other values
113 /*	are already implied by the context.
114 /* .IP mtype
115 /*	The remote MTA type.
116 /*	The only valid type is DSB_MTYPE_DNS.  The macro DSB_SKIP_RMTA
117 /*	conveniently expands into a null argument list for the
118 /*	remote MTA type and name.
119 /* .IP mname
120 /*	Remote MTA name.
121 /* .IP dtype
122 /*	The reply type.
123 /*	DSB_DTYPE_SMTP or DSB_DTYPE_UNIX.  The macro DSB_SKIP_REPLY
124 /*	conveniently expands into a null argument list for the reply
125 /*	type and text.
126 /* .IP dtext
127 /*	The reply text. The reply text is reset when dtype is
128 /*	DSB_SKIP_REPLY.
129 /* .IP reason_fmt
130 /*	The informal reason format.
131 /* SEE ALSO
132 /*	msg(3) diagnostics interface
133 /* DIAGNOSTICS
134 /*	Fatal: out of memory.
135 /* LICENSE
136 /* .ad
137 /* .fi
138 /*	The Secure Mailer license must be distributed with this software.
139 /* AUTHOR(S)
140 /*	Wietse Venema
141 /*	IBM T.J. Watson Research
142 /*	P.O. Box 704
143 /*	Yorktown Heights, NY 10598, USA
144 /*--*/
145 
146 /* System library. */
147 
148 #include <sys_defs.h>
149 #include <stdlib.h>			/* 44BSD stdarg.h uses abort() */
150 #include <stdarg.h>
151 #include <string.h>
152 
153 /* Utility library. */
154 
155 #include <msg.h>
156 #include <mymalloc.h>
157 #include <vstring.h>
158 
159 /* Global library. */
160 
161 #include <dsn_buf.h>
162 
163 /* Application-specific. */
164 
165 #define STR(x)	vstring_str(x)
166 
167 /* dsb_create - create delivery status buffer */
168 
dsb_create(void)169 DSN_BUF *dsb_create(void)
170 {
171     DSN_BUF *dsb;
172 
173     /*
174      * Some fields aren't needed until we want to report an error.
175      */
176     dsb = (DSN_BUF *) mymalloc(sizeof(*dsb));
177     dsb->status = vstring_alloc(10);
178     dsb->action = vstring_alloc(10);
179     dsb->mtype = vstring_alloc(10);
180     dsb->mname = vstring_alloc(100);
181     dsb->dtype = vstring_alloc(10);
182     dsb->dtext = vstring_alloc(100);
183     dsb->reason = vstring_alloc(100);
184 
185     return (dsb);
186 }
187 
188 /* dsb_free - destroy storage */
189 
dsb_free(DSN_BUF * dsb)190 void    dsb_free(DSN_BUF *dsb)
191 {
192     vstring_free(dsb->status);
193     vstring_free(dsb->action);
194     vstring_free(dsb->mtype);
195     vstring_free(dsb->mname);
196     vstring_free(dsb->dtype);
197     vstring_free(dsb->dtext);
198     vstring_free(dsb->reason);
199     myfree((void *) dsb);
200 }
201 
202  /*
203   * Initial versions of this code represented unavailable inputs with null
204   * pointers, which produced fragile and hard to maintain code. The current
205   * code uses empty strings instead of null pointers.
206   *
207   * For safety we keep the test for null pointers in input. It's cheap.
208   */
209 #define DSB_TRUNCATE(s) \
210     do { VSTRING_RESET(s); VSTRING_TERMINATE(s); } while (0)
211 
212 #define NULL_OR_EMPTY(s) ((s) == 0 || *(s) == 0)
213 
214 #define DSB_ACTION(dsb, stat, act) \
215     vstring_strcpy((dsb)->action, !NULL_OR_EMPTY(act) ? (act) : "")
216 
217 #define DSB_MTA(dsb, type, name) do { \
218     if (NULL_OR_EMPTY(type) || NULL_OR_EMPTY(name)) { \
219 	DSB_TRUNCATE((dsb)->mtype); \
220 	DSB_TRUNCATE((dsb)->mname); \
221     } else { \
222 	vstring_strcpy((dsb)->mtype, (type)); \
223 	vstring_strcpy((dsb)->mname, (name)); \
224     } \
225 } while (0)
226 
227 #define DSB_DIAG(dsb, type, text) do { \
228     if (NULL_OR_EMPTY(type) || NULL_OR_EMPTY(text)) { \
229 	DSB_TRUNCATE((dsb)->dtype); \
230 	DSB_TRUNCATE((dsb)->dtext); \
231     } else { \
232 	vstring_strcpy((dsb)->dtype, (type)); \
233 	vstring_strcpy((dsb)->dtext, (text)); \
234     } \
235 } while (0)
236 
237 /* dsb_update - update formal attributes and informal text */
238 
dsb_update(DSN_BUF * dsb,const char * status,const char * action,const char * mtype,const char * mname,const char * dtype,const char * dtext,const char * format,...)239 DSN_BUF *dsb_update(DSN_BUF *dsb, const char *status, const char *action,
240 		            const char *mtype, const char *mname,
241 		            const char *dtype, const char *dtext,
242 		            const char *format,...)
243 {
244     va_list ap;
245 
246     vstring_strcpy(dsb->status, status);
247     DSB_ACTION(dsb, status, action);
248     DSB_MTA(dsb, mtype, mname);
249     DSB_DIAG(dsb, dtype, dtext);
250     va_start(ap, format);
251     vstring_vsprintf(dsb->reason, format, ap);
252     va_end(ap);
253 
254     return (dsb);
255 }
256 
257 /* vdsb_simple - update status and informal text, va_list form */
258 
vdsb_simple(DSN_BUF * dsb,const char * status,const char * format,va_list ap)259 DSN_BUF *vdsb_simple(DSN_BUF *dsb, const char *status, const char *format,
260 		             va_list ap)
261 {
262     vstring_strcpy(dsb->status, status);
263     DSB_TRUNCATE(dsb->action);
264     DSB_TRUNCATE(dsb->mtype);
265     DSB_TRUNCATE(dsb->mname);
266     DSB_TRUNCATE(dsb->dtype);
267     DSB_TRUNCATE(dsb->dtext);
268     vstring_vsprintf(dsb->reason, format, ap);
269 
270     return (dsb);
271 }
272 
273 /* dsb_simple - update status and informal text */
274 
dsb_simple(DSN_BUF * dsb,const char * status,const char * format,...)275 DSN_BUF *dsb_simple(DSN_BUF *dsb, const char *status, const char *format,...)
276 {
277     va_list ap;
278 
279     va_start(ap, format);
280     (void) vdsb_simple(dsb, status, format, ap);
281     va_end(ap);
282     return (dsb);
283 }
284 
285 /* dsb_unix - update status, UNIX diagnostic and informal text */
286 
dsb_unix(DSN_BUF * dsb,const char * status,const char * dtext,const char * format,...)287 DSN_BUF *dsb_unix(DSN_BUF *dsb, const char *status,
288 		          const char *dtext, const char *format,...)
289 {
290     va_list ap;
291 
292     vstring_strcpy(dsb->status, status);
293     DSB_TRUNCATE(dsb->action);
294     DSB_TRUNCATE(dsb->mtype);
295     DSB_TRUNCATE(dsb->mname);
296     vstring_strcpy(dsb->dtype, DSB_DTYPE_UNIX);
297     vstring_strcpy(dsb->dtext, dtext);
298     va_start(ap, format);
299     vstring_vsprintf(dsb->reason, format, ap);
300     va_end(ap);
301 
302     return (dsb);
303 }
304 
305 /* dsb_formal - update the formal fields */
306 
dsb_formal(DSN_BUF * dsb,const char * status,const char * action,const char * mtype,const char * mname,const char * dtype,const char * dtext)307 DSN_BUF *dsb_formal(DSN_BUF *dsb, const char *status, const char *action,
308 		            const char *mtype, const char *mname,
309 		            const char *dtype, const char *dtext)
310 {
311     vstring_strcpy(dsb->status, status);
312     DSB_ACTION(dsb, status, action);
313     DSB_MTA(dsb, mtype, mname);
314     DSB_DIAG(dsb, dtype, dtext);
315     return (dsb);
316 }
317 
318 /* dsb_status - update the status, reset other formal fields */
319 
dsb_status(DSN_BUF * dsb,const char * status)320 DSN_BUF *dsb_status(DSN_BUF *dsb, const char *status)
321 {
322     vstring_strcpy(dsb->status, status);
323     DSB_TRUNCATE(dsb->action);
324     DSB_TRUNCATE(dsb->mtype);
325     DSB_TRUNCATE(dsb->mname);
326     DSB_TRUNCATE(dsb->dtype);
327     DSB_TRUNCATE(dsb->dtext);
328     return (dsb);
329 }
330 
331 /* dsb_reset - reset all fields */
332 
dsb_reset(DSN_BUF * dsb)333 void    dsb_reset(DSN_BUF *dsb)
334 {
335     DSB_TRUNCATE(dsb->status);
336     DSB_TRUNCATE(dsb->action);
337     DSB_TRUNCATE(dsb->mtype);
338     DSB_TRUNCATE(dsb->mname);
339     DSB_TRUNCATE(dsb->dtype);
340     DSB_TRUNCATE(dsb->dtext);
341     DSB_TRUNCATE(dsb->reason);
342 }
343