1 # include <pwd.h>
2 # include "sendmail.h"
3 
4 SCCSID(@(#)savemail.c	3.44		09/24/82);
5 
6 /*
7 **  SAVEMAIL -- Save mail on error
8 **
9 **	If the MailBack flag is set, mail it back to the originator
10 **	together with an error message; otherwise, just put it in
11 **	dead.letter in the user's home directory (if he exists on
12 **	this machine).
13 **
14 **	Parameters:
15 **		none
16 **
17 **	Returns:
18 **		none
19 **
20 **	Side Effects:
21 **		Saves the letter, by writing or mailing it back to the
22 **		sender, or by putting it in dead.letter in her home
23 **		directory.
24 */
25 
26 savemail()
27 {
28 	register struct passwd *pw;
29 	register FILE *xfile;
30 	char buf[MAXLINE+1];
31 	extern struct passwd *getpwnam();
32 	register char *p;
33 	extern char *ttypath();
34 	static int exclusive;
35 	typedef int (*fnptr)();
36 
37 # ifdef DEBUG
38 	if (tTd(6, 1))
39 		printf("\nsavemail: exclusive %d\n", exclusive);
40 # endif DEBUG
41 
42 	if (exclusive++)
43 		return;
44 	if (CurEnv->e_class < 0)
45 	{
46 		message(Arpa_Info, "Dumping junk mail");
47 		return;
48 	}
49 	ForceMail = TRUE;
50 	FatalErrors = FALSE;
51 
52 	/*
53 	**  In the unhappy event we don't know who to return the mail
54 	**  to, make someone up.
55 	*/
56 
57 	if (CurEnv->e_from.q_paddr == NULL)
58 	{
59 		if (parse("root", &CurEnv->e_from, 0) == NULL)
60 		{
61 			syserr("Cannot parse root!");
62 			ExitStat = EX_SOFTWARE;
63 			finis();
64 		}
65 	}
66 	CurEnv->e_to = NULL;
67 
68 	/*
69 	**  If called from Eric Schmidt's network, do special mailback.
70 	**	Fundamentally, this is the mailback case except that
71 	**	it returns an OK exit status (assuming the return
72 	**	worked).
73 	**  Also, if the from address is not local, mail it back.
74 	*/
75 
76 	if (BerkNet)
77 	{
78 		ExitStat = EX_OK;
79 		MailBack = TRUE;
80 	}
81 	if (!bitset(M_LOCAL, CurEnv->e_from.q_mailer->m_flags))
82 		MailBack = TRUE;
83 
84 	/*
85 	**  If writing back, do it.
86 	**	If the user is still logged in on the same terminal,
87 	**	then write the error messages back to hir (sic).
88 	**	If not, set the MailBack flag so that it will get
89 	**	mailed back instead.
90 	*/
91 
92 	if (WriteBack)
93 	{
94 		p = ttypath();
95 		if (p == NULL || freopen(p, "w", stdout) == NULL)
96 		{
97 			MailBack = TRUE;
98 			errno = 0;
99 		}
100 		else
101 		{
102 			(void) fflush(Xscript);
103 			xfile = fopen(Transcript, "r");
104 			if (xfile == NULL)
105 				syserr("Cannot open %s", Transcript);
106 			expand("$n", buf, &buf[sizeof buf - 1], CurEnv);
107 			printf("\r\nMessage from %s...\r\n", buf);
108 			printf("Errors occurred while sending mail; transcript follows:\r\n");
109 			while (fgets(buf, sizeof buf, xfile) != NULL && !ferror(stdout))
110 				fputs(buf, stdout);
111 			if (ferror(stdout))
112 				(void) syserr("savemail: stdout: write err");
113 			(void) fclose(xfile);
114 		}
115 	}
116 
117 	/*
118 	**  If mailing back, do it.
119 	**	Throw away all further output.  Don't do aliases, since
120 	**	this could cause loops, e.g., if joe mails to x:joe,
121 	**	and for some reason the network for x: is down, then
122 	**	the response gets sent to x:joe, which gives a
123 	**	response, etc.  Also force the mail to be delivered
124 	**	even if a version of it has already been sent to the
125 	**	sender.
126 	*/
127 
128 	if (MailBack)
129 	{
130 		if (CurEnv->e_errorqueue == NULL)
131 			sendto(CurEnv->e_from.q_paddr, (ADDRESS *) NULL,
132 			       &CurEnv->e_errorqueue);
133 		if (returntosender("Unable to deliver mail",
134 				   CurEnv->e_errorqueue, TRUE) == 0)
135 			return;
136 	}
137 
138 	/*
139 	**  Save the message in dead.letter.
140 	**	If we weren't mailing back, and the user is local, we
141 	**	should save the message in dead.letter so that the
142 	**	poor person doesn't have to type it over again --
143 	**	and we all know what poor typists programmers are.
144 	**	However, if we are running a "smart" protocol, we don't
145 	**	bother to return the message, since the other end is
146 	**	expected to handle that.
147 	*/
148 
149 	if (ArpaMode)
150 		return;
151 	p = NULL;
152 	if (CurEnv->e_from.q_mailer == LocalMailer)
153 	{
154 		if (CurEnv->e_from.q_home != NULL)
155 			p = CurEnv->e_from.q_home;
156 		else if ((pw = getpwnam(CurEnv->e_from.q_user)) != NULL)
157 			p = pw->pw_dir;
158 	}
159 	if (p == NULL)
160 	{
161 		syserr("Can't return mail to %s", CurEnv->e_from.q_paddr);
162 # ifdef DEBUG
163 		p = "/usr/tmp";
164 # endif
165 	}
166 	if (p != NULL && TempFile != NULL)
167 	{
168 		auto ADDRESS *q;
169 		bool oldverb = Verbose;
170 
171 		/* we have a home directory; open dead.letter */
172 		Verbose = TRUE;
173 		message(Arpa_Info, "Saving message in dead.letter");
174 		Verbose = oldverb;
175 		define('z', p);
176 		expand("$z/dead.letter", buf, &buf[sizeof buf - 1], CurEnv);
177 		CurEnv->e_to = buf;
178 		q = NULL;
179 		sendto(buf, (ADDRESS *) NULL, &q);
180 		(void) deliver(q);
181 	}
182 
183 	/* add terminator to writeback message */
184 	if (WriteBack)
185 		printf("-----\r\n");
186 }
187 /*
188 **  RETURNTOSENDER -- return a message to the sender with an error.
189 **
190 **	Parameters:
191 **		msg -- the explanatory message.
192 **		returnto -- the queue of people to send the message to.
193 **		sendbody -- if TRUE, also send back the body of the
194 **			message; otherwise just send the header.
195 **
196 **	Returns:
197 **		zero -- if everything went ok.
198 **		else -- some error.
199 **
200 **	Side Effects:
201 **		Returns the current message to the sender via
202 **		mail.
203 */
204 
205 static bool	SendBody;
206 
207 #define MAXRETURNS	6	/* max depth of returning messages */
208 
209 returntosender(msg, returnto, sendbody)
210 	char *msg;
211 	ADDRESS *returnto;
212 	bool sendbody;
213 {
214 	char buf[MAXNAME];
215 	extern putheader(), errbody();
216 	register ENVELOPE *ee;
217 	extern ENVELOPE *newenvelope();
218 	ENVELOPE errenvelope;
219 	static int returndepth;
220 
221 # ifdef DEBUG
222 	if (tTd(6, 1))
223 	{
224 		printf("Return To Sender: msg=\"%s\", depth=%d, CurEnv=%x,\n",
225 		       msg, returndepth, CurEnv);
226 		printf("\treturnto=");
227 		printaddr(returnto, FALSE);
228 	}
229 # endif DEBUG
230 
231 	if (++returndepth >= MAXRETURNS)
232 	{
233 		if (returndepth != MAXRETURNS)
234 			syserr("returntosender: infinite recursion on %s", returnto->q_paddr);
235 		/* don't "unrecurse" and fake a clean exit */
236 		/* returndepth--; */
237 		return (0);
238 	}
239 
240 	NoAlias = TRUE;
241 	SendBody = sendbody;
242 	define('g', "$f");
243 	ee = newenvelope(&errenvelope);
244 	ee->e_puthdr = putheader;
245 	ee->e_putbody = errbody;
246 	addheader("date", "$b", ee);
247 	addheader("from", "$g (Mail Delivery Subsystem)", ee);
248 	addheader("to", returnto->q_paddr, ee);
249 	addheader("subject", msg, ee);
250 
251 	/* fake up an address header for the from person */
252 	expand("$n", buf, &buf[sizeof buf - 1], CurEnv);
253 	if (parse(buf, &ee->e_from, -1) == NULL)
254 	{
255 		syserr("Can't parse myself!");
256 		ExitStat = EX_SOFTWARE;
257 		returndepth--;
258 		return (-1);
259 	}
260 	ee->e_sendqueue = returnto;
261 
262 	/* push state into submessage */
263 	CurEnv = ee;
264 	define('f', "$n");
265 	define('x', "Mail Delivery Subsystem");
266 
267 	/* actually deliver the error message */
268 	sendall(ee, FALSE);
269 
270 	/* do any closing error processing */
271 	checkerrors(ee);
272 
273 	/* restore state */
274 	dropenvelope(ee);
275 	CurEnv = CurEnv->e_parent;
276 	returndepth--;
277 
278 	/* should check for delivery errors here */
279 	return (0);
280 }
281 /*
282 **  ERRBODY -- output the body of an error message.
283 **
284 **	Typically this is a copy of the transcript plus a copy of the
285 **	original offending message.
286 **
287 **	Parameters:
288 **		xfile -- the transcript file.
289 **		fp -- the output file.
290 **		xdot -- if set, use the SMTP hidden dot algorithm.
291 **
292 **	Returns:
293 **		none
294 **
295 **	Side Effects:
296 **		Outputs the body of an error message.
297 */
298 
299 errbody(fp, m, xdot)
300 	register FILE *fp;
301 	register struct mailer *m;
302 	bool xdot;
303 {
304 	register FILE *xfile;
305 	char buf[MAXLINE];
306 	bool fullsmtp = bitset(M_FULLSMTP, m->m_flags);
307 
308 	(void) fflush(stdout);
309 	if ((xfile = fopen(Transcript, "r")) == NULL)
310 		syserr("Cannot open %s", Transcript);
311 	errno = 0;
312 
313 	/*
314 	**  Output transcript of errors
315 	*/
316 
317 	fprintf(fp, "   ----- Transcript of session follows -----\n");
318 	(void) fflush(Xscript);
319 	while (fgets(buf, sizeof buf, xfile) != NULL)
320 		putline(buf, fp, fullsmtp);
321 
322 	/*
323 	**  Output text of original message
324 	*/
325 
326 	if (NoReturn)
327 		fprintf(fp, "\n   ----- Return message suppressed -----\n\n");
328 	else if (TempFile != NULL)
329 	{
330 		if (SendBody)
331 		{
332 			fprintf(fp, "\n   ----- Unsent message follows -----\n");
333 			(void) fflush(fp);
334 			putheader(fp, m, CurEnv->e_parent);
335 			fprintf(fp, "\n");
336 			putbody(fp, m, xdot);
337 		}
338 		else
339 		{
340 			fprintf(fp, "\n  ----- Message header follows -----\n");
341 			(void) fflush(fp);
342 			putheader(fp, m, CurEnv);
343 		}
344 	}
345 	else
346 		fprintf(fp, "\n  ----- No message was collected -----\n\n");
347 
348 	/*
349 	**  Cleanup and exit
350 	*/
351 
352 	(void) fclose(xfile);
353 	if (errno != 0)
354 		syserr("errbody: I/O error");
355 }
356