1 /*
2 **  Sendmail
3 **  Copyright (c) 1983  Eric P. Allman
4 **  Berkeley, California
5 **
6 **  Copyright (c) 1983 Regents of the University of California.
7 **  All rights reserved.  The Berkeley software License Agreement
8 **  specifies the terms and conditions for redistribution.
9 */
10 
11 #ifndef lint
12 static char	SccsId[] = "@(#)savemail.c	5.1 (Berkeley) 06/07/85";
13 #endif not lint
14 
15 # include <pwd.h>
16 # include "sendmail.h"
17 
18 SCCSID(@(#)savemail.c	5.1		06/07/85);
19 
20 /*
21 **  SAVEMAIL -- Save mail on error
22 **
23 **	If mailing back errors, mail it back to the originator
24 **	together with an error message; otherwise, just put it in
25 **	dead.letter in the user's home directory (if he exists on
26 **	this machine).
27 **
28 **	Parameters:
29 **		e -- the envelope containing the message in error.
30 **
31 **	Returns:
32 **		none
33 **
34 **	Side Effects:
35 **		Saves the letter, by writing or mailing it back to the
36 **		sender, or by putting it in dead.letter in her home
37 **		directory.
38 */
39 
40 savemail(e)
41 	register ENVELOPE *e;
42 {
43 	register struct passwd *pw;
44 	register FILE *xfile;
45 	char buf[MAXLINE+1];
46 	extern struct passwd *getpwnam();
47 	register char *p;
48 	extern char *ttypath();
49 	typedef int (*fnptr)();
50 
51 # ifdef DEBUG
52 	if (tTd(6, 1))
53 		printf("\nsavemail\n");
54 # endif DEBUG
55 
56 	if (bitset(EF_RESPONSE, e->e_flags))
57 		return;
58 	if (e->e_class < 0)
59 	{
60 		message(Arpa_Info, "Dumping junk mail");
61 		return;
62 	}
63 	ForceMail = TRUE;
64 	e->e_flags &= ~EF_FATALERRS;
65 
66 	/*
67 	**  In the unhappy event we don't know who to return the mail
68 	**  to, make someone up.
69 	*/
70 
71 	if (e->e_from.q_paddr == NULL)
72 	{
73 		if (parseaddr("root", &e->e_from, 0, '\0') == NULL)
74 		{
75 			syserr("Cannot parse root!");
76 			ExitStat = EX_SOFTWARE;
77 			finis();
78 		}
79 	}
80 	e->e_to = NULL;
81 
82 	/*
83 	**  If called from Eric Schmidt's network, do special mailback.
84 	**	Fundamentally, this is the mailback case except that
85 	**	it returns an OK exit status (assuming the return
86 	**	worked).
87 	**  Also, if the from address is not local, mail it back.
88 	*/
89 
90 	if (ErrorMode == EM_BERKNET)
91 	{
92 		ExitStat = EX_OK;
93 		ErrorMode = EM_MAIL;
94 	}
95 	if (!bitnset(M_LOCAL, e->e_from.q_mailer->m_flags))
96 		ErrorMode = EM_MAIL;
97 
98 	/*
99 	**  If writing back, do it.
100 	**	If the user is still logged in on the same terminal,
101 	**	then write the error messages back to hir (sic).
102 	**	If not, mail back instead.
103 	*/
104 
105 	if (ErrorMode == EM_WRITE)
106 	{
107 		p = ttypath();
108 		if (p == NULL || freopen(p, "w", stdout) == NULL)
109 		{
110 			ErrorMode = EM_MAIL;
111 			errno = 0;
112 		}
113 		else
114 		{
115 			expand("\001n", buf, &buf[sizeof buf - 1], e);
116 			printf("\r\nMessage from %s...\r\n", buf);
117 			printf("Errors occurred while sending mail.\r\n");
118 			if (e->e_xfp != NULL)
119 			{
120 				(void) fflush(e->e_xfp);
121 				xfile = fopen(queuename(e, 'x'), "r");
122 			}
123 			else
124 				xfile = NULL;
125 			if (xfile == NULL)
126 			{
127 				syserr("Cannot open %s", queuename(e, 'x'));
128 				printf("Transcript of session is unavailable.\r\n");
129 			}
130 			else
131 			{
132 				printf("Transcript follows:\r\n");
133 				while (fgets(buf, sizeof buf, xfile) != NULL &&
134 				       !ferror(stdout))
135 					fputs(buf, stdout);
136 				(void) fclose(xfile);
137 			}
138 			if (ferror(stdout))
139 				(void) syserr("savemail: stdout: write err");
140 		}
141 	}
142 
143 	/*
144 	**  If mailing back, do it.
145 	**	Throw away all further output.  Don't do aliases, since
146 	**	this could cause loops, e.g., if joe mails to x:joe,
147 	**	and for some reason the network for x: is down, then
148 	**	the response gets sent to x:joe, which gives a
149 	**	response, etc.  Also force the mail to be delivered
150 	**	even if a version of it has already been sent to the
151 	**	sender.
152 	*/
153 
154 	if (ErrorMode == EM_MAIL)
155 	{
156 		if (e->e_errorqueue == NULL)
157 			sendtolist(e->e_from.q_paddr, (ADDRESS *) NULL,
158 			       &e->e_errorqueue);
159 		if (returntosender(e->e_message != NULL ? e->e_message :
160 				   "Unable to deliver mail",
161 				   e->e_errorqueue, TRUE) == 0)
162 			return;
163 	}
164 
165 	/*
166 	**  Save the message in dead.letter.
167 	**	If we weren't mailing back, and the user is local, we
168 	**	should save the message in dead.letter so that the
169 	**	poor person doesn't have to type it over again --
170 	**	and we all know what poor typists programmers are.
171 	*/
172 
173 	p = NULL;
174 	if (e->e_from.q_mailer == LocalMailer)
175 	{
176 		if (e->e_from.q_home != NULL)
177 			p = e->e_from.q_home;
178 		else if ((pw = getpwnam(e->e_from.q_user)) != NULL)
179 			p = pw->pw_dir;
180 	}
181 	if (p == NULL)
182 	{
183 		syserr("Can't return mail to %s", e->e_from.q_paddr);
184 # ifdef DEBUG
185 		p = "/usr/tmp";
186 # endif
187 	}
188 	if (p != NULL && e->e_dfp != NULL)
189 	{
190 		auto ADDRESS *q;
191 		bool oldverb = Verbose;
192 
193 		/* we have a home directory; open dead.letter */
194 		define('z', p, e);
195 		expand("\001z/dead.letter", buf, &buf[sizeof buf - 1], e);
196 		Verbose = TRUE;
197 		message(Arpa_Info, "Saving message in %s", buf);
198 		Verbose = oldverb;
199 		e->e_to = buf;
200 		q = NULL;
201 		sendtolist(buf, (ADDRESS *) NULL, &q);
202 		(void) deliver(e, q);
203 	}
204 
205 	/* add terminator to writeback message */
206 	if (ErrorMode == EM_WRITE)
207 		printf("-----\r\n");
208 }
209 /*
210 **  RETURNTOSENDER -- return a message to the sender with an error.
211 **
212 **	Parameters:
213 **		msg -- the explanatory message.
214 **		returnq -- the queue of people to send the message to.
215 **		sendbody -- if TRUE, also send back the body of the
216 **			message; otherwise just send the header.
217 **
218 **	Returns:
219 **		zero -- if everything went ok.
220 **		else -- some error.
221 **
222 **	Side Effects:
223 **		Returns the current message to the sender via
224 **		mail.
225 */
226 
227 static bool	SendBody;
228 
229 #define MAXRETURNS	6	/* max depth of returning messages */
230 
231 returntosender(msg, returnq, sendbody)
232 	char *msg;
233 	ADDRESS *returnq;
234 	bool sendbody;
235 {
236 	char buf[MAXNAME];
237 	extern putheader(), errbody();
238 	register ENVELOPE *ee;
239 	extern ENVELOPE *newenvelope();
240 	ENVELOPE errenvelope;
241 	static int returndepth;
242 	register ADDRESS *q;
243 
244 # ifdef DEBUG
245 	if (tTd(6, 1))
246 	{
247 		printf("Return To Sender: msg=\"%s\", depth=%d, CurEnv=%x,\n",
248 		       msg, returndepth, CurEnv);
249 		printf("\treturnto=");
250 		printaddr(returnq, TRUE);
251 	}
252 # endif DEBUG
253 
254 	if (++returndepth >= MAXRETURNS)
255 	{
256 		if (returndepth != MAXRETURNS)
257 			syserr("returntosender: infinite recursion on %s", returnq->q_paddr);
258 		/* don't "unrecurse" and fake a clean exit */
259 		/* returndepth--; */
260 		return (0);
261 	}
262 
263 	SendBody = sendbody;
264 	define('g', "\001f", CurEnv);
265 	ee = newenvelope(&errenvelope);
266 	ee->e_puthdr = putheader;
267 	ee->e_putbody = errbody;
268 	ee->e_flags |= EF_RESPONSE;
269 	ee->e_sendqueue = returnq;
270 	openxscript(ee);
271 	for (q = returnq; q != NULL; q = q->q_next)
272 	{
273 		if (q->q_alias == NULL)
274 			addheader("to", q->q_paddr, ee);
275 	}
276 	(void) sprintf(buf, "Returned mail: %s", msg);
277 	addheader("subject", buf, ee);
278 
279 	/* fake up an address header for the from person */
280 	expand("\001n", buf, &buf[sizeof buf - 1], CurEnv);
281 	if (parseaddr(buf, &ee->e_from, -1, '\0') == NULL)
282 	{
283 		syserr("Can't parse myself!");
284 		ExitStat = EX_SOFTWARE;
285 		returndepth--;
286 		return (-1);
287 	}
288 	loweraddr(&ee->e_from);
289 
290 	/* push state into submessage */
291 	CurEnv = ee;
292 	define('f', "\001n", ee);
293 	define('x', "Mail Delivery Subsystem", ee);
294 	eatheader(ee);
295 
296 	/* actually deliver the error message */
297 	sendall(ee, SM_DEFAULT);
298 
299 	/* restore state */
300 	dropenvelope(ee);
301 	CurEnv = CurEnv->e_parent;
302 	returndepth--;
303 
304 	/* should check for delivery errors here */
305 	return (0);
306 }
307 /*
308 **  ERRBODY -- output the body of an error message.
309 **
310 **	Typically this is a copy of the transcript plus a copy of the
311 **	original offending message.
312 **
313 **	Parameters:
314 **		fp -- the output file.
315 **		m -- the mailer to output to.
316 **		e -- the envelope we are working in.
317 **
318 **	Returns:
319 **		none
320 **
321 **	Side Effects:
322 **		Outputs the body of an error message.
323 */
324 
325 errbody(fp, m, e)
326 	register FILE *fp;
327 	register struct mailer *m;
328 	register ENVELOPE *e;
329 {
330 	register FILE *xfile;
331 	char buf[MAXLINE];
332 	char *p;
333 
334 	/*
335 	**  Output transcript of errors
336 	*/
337 
338 	(void) fflush(stdout);
339 	p = queuename(e->e_parent, 'x');
340 	if ((xfile = fopen(p, "r")) == NULL)
341 	{
342 		syserr("Cannot open %s", p);
343 		fprintf(fp, "  ----- Transcript of session is unavailable -----\n");
344 	}
345 	else
346 	{
347 		fprintf(fp, "   ----- Transcript of session follows -----\n");
348 		if (e->e_xfp != NULL)
349 			(void) fflush(e->e_xfp);
350 		while (fgets(buf, sizeof buf, xfile) != NULL)
351 			putline(buf, fp, m);
352 		(void) fclose(xfile);
353 	}
354 	errno = 0;
355 
356 	/*
357 	**  Output text of original message
358 	*/
359 
360 	if (NoReturn)
361 		fprintf(fp, "\n   ----- Return message suppressed -----\n\n");
362 	else if (e->e_parent->e_dfp != NULL)
363 	{
364 		if (SendBody)
365 		{
366 			putline("\n", fp, m);
367 			putline("   ----- Unsent message follows -----\n", fp, m);
368 			(void) fflush(fp);
369 			putheader(fp, m, e->e_parent);
370 			putline("\n", fp, m);
371 			putbody(fp, m, e->e_parent);
372 		}
373 		else
374 		{
375 			putline("\n", fp, m);
376 			putline("  ----- Message header follows -----\n", fp, m);
377 			(void) fflush(fp);
378 			putheader(fp, m, e->e_parent);
379 		}
380 	}
381 	else
382 	{
383 		putline("\n", fp, m);
384 		putline("  ----- No message was collected -----\n", fp, m);
385 		putline("\n", fp, m);
386 	}
387 
388 	/*
389 	**  Cleanup and exit
390 	*/
391 
392 	if (errno != 0)
393 		syserr("errbody: I/O error");
394 }
395