1 # include <pwd.h>
2 # include "sendmail.h"
3 
4 SCCSID(@(#)savemail.c	3.41		08/22/82);
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 <= PRI_JUNK)
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, 1, (ADDRESS *) NULL, &CurEnv->e_errorqueue);
132 		if (returntosender("Unable to deliver mail", CurEnv->e_errorqueue, TRUE) == 0)
133 			return;
134 	}
135 
136 	/*
137 	**  Save the message in dead.letter.
138 	**	If we weren't mailing back, and the user is local, we
139 	**	should save the message in dead.letter so that the
140 	**	poor person doesn't have to type it over again --
141 	**	and we all know what poor typists programmers are.
142 	**	However, if we are running a "smart" protocol, we don't
143 	**	bother to return the message, since the other end is
144 	**	expected to handle that.
145 	*/
146 
147 	if (ArpaMode)
148 		return;
149 	p = NULL;
150 	if (CurEnv->e_from.q_mailer == LocalMailer)
151 	{
152 		if (CurEnv->e_from.q_home != NULL)
153 			p = CurEnv->e_from.q_home;
154 		else if ((pw = getpwnam(CurEnv->e_from.q_user)) != NULL)
155 			p = pw->pw_dir;
156 	}
157 	if (p == NULL)
158 	{
159 		syserr("Can't return mail to %s", CurEnv->e_from.q_paddr);
160 # ifdef DEBUG
161 		p = "/usr/tmp";
162 # endif
163 	}
164 	if (p != NULL && TempFile != NULL)
165 	{
166 		auto ADDRESS *q;
167 		bool oldverb = Verbose;
168 
169 		/* we have a home directory; open dead.letter */
170 		Verbose = TRUE;
171 		message(Arpa_Info, "Saving message in dead.letter");
172 		Verbose = oldverb;
173 		define('z', p);
174 		expand("$z/dead.letter", buf, &buf[sizeof buf - 1], CurEnv);
175 		CurEnv->e_to = buf;
176 		q = NULL;
177 		sendto(buf, -1, (ADDRESS *) NULL, &q);
178 		(void) deliver(q);
179 	}
180 
181 	/* add terminator to writeback message */
182 	if (WriteBack)
183 		printf("-----\r\n");
184 }
185 /*
186 **  RETURNTOSENDER -- return a message to the sender with an error.
187 **
188 **	Parameters:
189 **		msg -- the explanatory message.
190 **		returnto -- the queue of people to send the message to.
191 **		sendbody -- if TRUE, also send back the body of the
192 **			message; otherwise just send the header.
193 **
194 **	Returns:
195 **		zero -- if everything went ok.
196 **		else -- some error.
197 **
198 **	Side Effects:
199 **		Returns the current message to the sender via
200 **		mail.
201 */
202 
203 static bool	SendBody;
204 
205 #define MAXRETURNS	6	/* max depth of returning messages */
206 
207 returntosender(msg, returnto, sendbody)
208 	char *msg;
209 	ADDRESS *returnto;
210 	bool sendbody;
211 {
212 	char buf[MAXNAME];
213 	extern putheader(), errbody();
214 	register ENVELOPE *ee;
215 	extern ENVELOPE *newenvelope();
216 	ENVELOPE errenvelope;
217 	static int returndepth;
218 
219 # ifdef DEBUG
220 	if (tTd(6, 1))
221 	{
222 		printf("Return To Sender: msg=\"%s\", depth=%d, CurEnv=%x,\n",
223 		       msg, returndepth, CurEnv);
224 		printf("\treturnto=");
225 		printaddr(returnto, FALSE);
226 	}
227 # endif DEBUG
228 
229 	if (++returndepth >= MAXRETURNS)
230 	{
231 		if (returndepth != MAXRETURNS)
232 			syserr("returntosender: infinite recursion on %s", returnto->q_paddr);
233 		/* don't "unrecurse" and fake a clean exit */
234 		/* returndepth--; */
235 		return (0);
236 	}
237 
238 	NoAlias = TRUE;
239 	SendBody = sendbody;
240 	ee = newenvelope(&errenvelope);
241 	ee->e_puthdr = putheader;
242 	ee->e_putbody = errbody;
243 	addheader("date", "$b", ee);
244 	addheader("from", "$g (Mail Delivery Subsystem)", ee);
245 	addheader("to", returnto->q_paddr, ee);
246 	addheader("subject", msg, ee);
247 
248 	/* fake up an address header for the from person */
249 	expand("$n", buf, &buf[sizeof buf - 1], CurEnv);
250 	if (parse(buf, &ee->e_from, -1) == NULL)
251 	{
252 		syserr("Can't parse myself!");
253 		ExitStat = EX_SOFTWARE;
254 		returndepth--;
255 		return (-1);
256 	}
257 	ee->e_sendqueue = returnto;
258 
259 	/* push state into submessage */
260 	CurEnv = ee;
261 	define('f', "$n");
262 	define('x', "Mail Delivery Subsystem");
263 
264 	/* actually deliver the error message */
265 	sendall(ee, FALSE);
266 
267 	/* do any closing error processing */
268 	checkerrors(ee);
269 
270 	/* restore state */
271 	dropenvelope(ee);
272 	CurEnv = CurEnv->e_parent;
273 	returndepth--;
274 
275 	/* should check for delivery errors here */
276 	return (0);
277 }
278 /*
279 **  ERRBODY -- output the body of an error message.
280 **
281 **	Typically this is a copy of the transcript plus a copy of the
282 **	original offending message.
283 **
284 **	Parameters:
285 **		xfile -- the transcript file.
286 **		fp -- the output file.
287 **		xdot -- if set, use the SMTP hidden dot algorithm.
288 **
289 **	Returns:
290 **		none
291 **
292 **	Side Effects:
293 **		Outputs the body of an error message.
294 */
295 
296 errbody(fp, m, xdot)
297 	register FILE *fp;
298 	register struct mailer *m;
299 	bool xdot;
300 {
301 	register FILE *xfile;
302 	char buf[MAXLINE];
303 	bool fullsmtp = bitset(M_FULLSMTP, m->m_flags);
304 
305 	(void) fflush(stdout);
306 	if ((xfile = fopen(Transcript, "r")) == NULL)
307 		syserr("Cannot open %s", Transcript);
308 	errno = 0;
309 
310 	/*
311 	**  Output transcript of errors
312 	*/
313 
314 	fprintf(fp, "   ----- Transcript of session follows -----\n");
315 	(void) fflush(Xscript);
316 	while (fgets(buf, sizeof buf, xfile) != NULL)
317 		putline(buf, fp, fullsmtp);
318 
319 	/*
320 	**  Output text of original message
321 	*/
322 
323 	if (NoReturn)
324 		fprintf(fp, "\n   ----- Return message suppressed -----\n\n");
325 	else if (TempFile != NULL)
326 	{
327 		if (SendBody)
328 		{
329 			fprintf(fp, "\n   ----- Unsent message follows -----\n");
330 			(void) fflush(fp);
331 			putheader(fp, m, CurEnv->e_parent);
332 			fprintf(fp, "\n");
333 			putbody(fp, m, xdot);
334 		}
335 		else
336 		{
337 			fprintf(fp, "\n  ----- Message header follows -----\n");
338 			(void) fflush(fp);
339 			putheader(fp, m, CurEnv);
340 		}
341 	}
342 	else
343 		fprintf(fp, "\n  ----- No message was collected -----\n\n");
344 
345 	/*
346 	**  Cleanup and exit
347 	*/
348 
349 	(void) fclose(xfile);
350 	if (errno != 0)
351 		syserr("errbody: I/O error");
352 }
353