1 /*
2  * Copyright (c) 1988 Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms are permitted
6  * provided that this notice is preserved and that due credit is given
7  * to the University of California at Berkeley. The name of the University
8  * may not be used to endorse or promote products derived from this
9  * software without specific prior written permission. This software
10  * is provided ``as is'' without express or implied warranty.
11  *
12  *  Sendmail
13  *  Copyright (c) 1983  Eric P. Allman
14  *  Berkeley, California
15  */
16 
17 #ifndef lint
18 static char sccsid[] = "@(#)recipient.c	5.11 (Berkeley) 03/13/88";
19 #endif /* not lint */
20 
21 # include <pwd.h>
22 # include "sendmail.h"
23 # include <sys/stat.h>
24 
25 /*
26 **  SENDTOLIST -- Designate a send list.
27 **
28 **	The parameter is a comma-separated list of people to send to.
29 **	This routine arranges to send to all of them.
30 **
31 **	Parameters:
32 **		list -- the send list.
33 **		ctladdr -- the address template for the person to
34 **			send to -- effective uid/gid are important.
35 **			This is typically the alias that caused this
36 **			expansion.
37 **		sendq -- a pointer to the head of a queue to put
38 **			these people into.
39 **
40 **	Returns:
41 **		none
42 **
43 **	Side Effects:
44 **		none.
45 */
46 
47 # define MAXRCRSN	10
48 
49 sendtolist(list, ctladdr, sendq)
50 	char *list;
51 	ADDRESS *ctladdr;
52 	ADDRESS **sendq;
53 {
54 	register char *p;
55 	register ADDRESS *al;	/* list of addresses to send to */
56 	bool firstone;		/* set on first address sent */
57 	bool selfref;		/* set if this list includes ctladdr */
58 	char delimiter;		/* the address delimiter */
59 
60 # ifdef DEBUG
61 	if (tTd(25, 1))
62 	{
63 		printf("sendto: %s\n   ctladdr=", list);
64 		printaddr(ctladdr, FALSE);
65 	}
66 # endif DEBUG
67 
68 	/* heuristic to determine old versus new style addresses */
69 	if (ctladdr == NULL &&
70 	    (index(list, ',') != NULL || index(list, ';') != NULL ||
71 	     index(list, '<') != NULL || index(list, '(') != NULL))
72 		CurEnv->e_flags &= ~EF_OLDSTYLE;
73 	delimiter = ' ';
74 	if (!bitset(EF_OLDSTYLE, CurEnv->e_flags) || ctladdr != NULL)
75 		delimiter = ',';
76 
77 	firstone = TRUE;
78 	selfref = FALSE;
79 	al = NULL;
80 
81 	for (p = list; *p != '\0'; )
82 	{
83 		register ADDRESS *a;
84 		extern char *DelimChar;		/* defined in prescan */
85 
86 		/* parse the address */
87 		while (isspace(*p) || *p == ',')
88 			p++;
89 		a = parseaddr(p, (ADDRESS *) NULL, 1, delimiter);
90 		p = DelimChar;
91 		if (a == NULL)
92 			continue;
93 		a->q_next = al;
94 		a->q_alias = ctladdr;
95 
96 		/* see if this should be marked as a primary address */
97 		if (ctladdr == NULL ||
98 		    (firstone && *p == '\0' && bitset(QPRIMARY, ctladdr->q_flags)))
99 			a->q_flags |= QPRIMARY;
100 
101 		/* put on send queue or suppress self-reference */
102 		if (ctladdr != NULL && sameaddr(ctladdr, a))
103 			selfref = TRUE;
104 		else
105 			al = a;
106 		firstone = FALSE;
107 	}
108 
109 	/* if this alias doesn't include itself, delete ctladdr */
110 	if (!selfref && ctladdr != NULL)
111 		ctladdr->q_flags |= QDONTSEND;
112 
113 	/* arrange to send to everyone on the local send list */
114 	while (al != NULL)
115 	{
116 		register ADDRESS *a = al;
117 		extern ADDRESS *recipient();
118 
119 		al = a->q_next;
120 		a = recipient(a, sendq);
121 
122 		/* arrange to inherit full name */
123 		if (a->q_fullname == NULL && ctladdr != NULL)
124 			a->q_fullname = ctladdr->q_fullname;
125 	}
126 
127 	CurEnv->e_to = NULL;
128 }
129 /*
130 **  RECIPIENT -- Designate a message recipient
131 **
132 **	Saves the named person for future mailing.
133 **
134 **	Parameters:
135 **		a -- the (preparsed) address header for the recipient.
136 **		sendq -- a pointer to the head of a queue to put the
137 **			recipient in.  Duplicate supression is done
138 **			in this queue.
139 **
140 **	Returns:
141 **		The actual address in the queue.  This will be "a" if
142 **		the address is not a duplicate, else the original address.
143 **
144 **	Side Effects:
145 **		none.
146 */
147 
148 ADDRESS *
149 recipient(a, sendq)
150 	register ADDRESS *a;
151 	register ADDRESS **sendq;
152 {
153 	register ADDRESS *q;
154 	ADDRESS **pq;
155 	register struct mailer *m;
156 	register char *p;
157 	bool quoted = FALSE;		/* set if the addr has a quote bit */
158 	char buf[MAXNAME];		/* unquoted image of the user name */
159 	extern ADDRESS *getctladdr();
160 	extern bool safefile();
161 
162 	CurEnv->e_to = a->q_paddr;
163 	m = a->q_mailer;
164 	errno = 0;
165 # ifdef DEBUG
166 	if (tTd(26, 1))
167 	{
168 		printf("\nrecipient: ");
169 		printaddr(a, FALSE);
170 	}
171 # endif DEBUG
172 
173 	/* break aliasing loops */
174 	if (AliasLevel > MAXRCRSN)
175 	{
176 		usrerr("aliasing/forwarding loop broken");
177 		return (a);
178 	}
179 
180 	/*
181 	**  Finish setting up address structure.
182 	*/
183 
184 	/* set the queue timeout */
185 	a->q_timeout = TimeOut;
186 
187 	/* map user & host to lower case if requested on non-aliases */
188 	if (a->q_alias == NULL)
189 		loweraddr(a);
190 
191 	/* get unquoted user for file, program or user.name check */
192 	(void) strcpy(buf, a->q_user);
193 	for (p = buf; *p != '\0' && !quoted; p++)
194 	{
195 		if (!isascii(*p) && (*p & 0377) != (SpaceSub & 0377))
196 			quoted = TRUE;
197 	}
198 	stripquotes(buf, TRUE);
199 
200 	/* do sickly crude mapping for program mailing, etc. */
201 	if (m == LocalMailer && buf[0] == '|')
202 	{
203 		a->q_mailer = m = ProgMailer;
204 		a->q_user++;
205 		if (a->q_alias == NULL && !tTd(0, 1) && !QueueRun && !ForceMail)
206 		{
207 			a->q_flags |= QDONTSEND|QBADADDR;
208 			usrerr("Cannot mail directly to programs");
209 		}
210 	}
211 
212 	/*
213 	**  Look up this person in the recipient list.
214 	**	If they are there already, return, otherwise continue.
215 	**	If the list is empty, just add it.  Notice the cute
216 	**	hack to make from addresses suppress things correctly:
217 	**	the QDONTSEND bit will be set in the send list.
218 	**	[Please note: the emphasis is on "hack."]
219 	*/
220 
221 	for (pq = sendq; (q = *pq) != NULL; pq = &q->q_next)
222 	{
223 		if (!ForceMail && sameaddr(q, a))
224 		{
225 # ifdef DEBUG
226 			if (tTd(26, 1))
227 			{
228 				printf("%s in sendq: ", a->q_paddr);
229 				printaddr(q, FALSE);
230 			}
231 # endif DEBUG
232 			if (!bitset(QDONTSEND, a->q_flags))
233 				message(Arpa_Info, "duplicate suppressed");
234 			if (!bitset(QPRIMARY, q->q_flags))
235 				q->q_flags |= a->q_flags;
236 			return (q);
237 		}
238 	}
239 
240 	/* add address on list */
241 	*pq = a;
242 	a->q_next = NULL;
243 	CurEnv->e_nrcpts++;
244 
245 	/*
246 	**  Alias the name and handle :include: specs.
247 	*/
248 
249 	if (m == LocalMailer && !bitset(QDONTSEND, a->q_flags))
250 	{
251 		if (strncmp(a->q_user, ":include:", 9) == 0)
252 		{
253 			a->q_flags |= QDONTSEND;
254 			if (a->q_alias == NULL && !tTd(0, 1) && !QueueRun && !ForceMail)
255 			{
256 				a->q_flags |= QBADADDR;
257 				usrerr("Cannot mail directly to :include:s");
258 			}
259 			else
260 			{
261 				message(Arpa_Info, "including file %s", &a->q_user[9]);
262 				include(&a->q_user[9], " sending", a, sendq);
263 			}
264 		}
265 		else
266 			alias(a, sendq);
267 	}
268 
269 	/*
270 	**  If the user is local and still being sent, verify that
271 	**  the address is good.  If it is, try to forward.
272 	**  If the address is already good, we have a forwarding
273 	**  loop.  This can be broken by just sending directly to
274 	**  the user (which is probably correct anyway).
275 	*/
276 
277 	if (!bitset(QDONTSEND, a->q_flags) && m == LocalMailer)
278 	{
279 		struct stat stb;
280 		extern bool writable();
281 
282 		/* see if this is to a file */
283 		if (buf[0] == '/')
284 		{
285 			p = rindex(buf, '/');
286 			/* check if writable or creatable */
287 			if (a->q_alias == NULL && !tTd(0, 1) && !QueueRun && !ForceMail)
288 			{
289 				a->q_flags |= QDONTSEND|QBADADDR;
290 				usrerr("Cannot mail directly to files");
291 			}
292 			else if ((stat(buf, &stb) >= 0) ? (!writable(&stb)) :
293 			    (*p = '\0', !safefile(buf, getruid(), S_IWRITE|S_IEXEC)))
294 			{
295 				a->q_flags |= QBADADDR;
296 				giveresponse(EX_CANTCREAT, m, CurEnv);
297 			}
298 		}
299 		else
300 		{
301 			register struct passwd *pw;
302 			extern struct passwd *finduser();
303 
304 			/* warning -- finduser may trash buf */
305 			pw = finduser(buf);
306 			if (pw == NULL)
307 			{
308 				a->q_flags |= QBADADDR;
309 				giveresponse(EX_NOUSER, m, CurEnv);
310 			}
311 			else
312 			{
313 				char nbuf[MAXNAME];
314 
315 				if (strcmp(a->q_user, pw->pw_name) != 0)
316 				{
317 					a->q_user = newstr(pw->pw_name);
318 					(void) strcpy(buf, pw->pw_name);
319 				}
320 				a->q_home = newstr(pw->pw_dir);
321 				a->q_uid = pw->pw_uid;
322 				a->q_gid = pw->pw_gid;
323 				a->q_flags |= QGOODUID;
324 				buildfname(pw->pw_gecos, pw->pw_name, nbuf);
325 				if (nbuf[0] != '\0')
326 					a->q_fullname = newstr(nbuf);
327 				if (!quoted)
328 					forward(a, sendq);
329 			}
330 		}
331 	}
332 	return (a);
333 }
334 /*
335 **  FINDUSER -- find the password entry for a user.
336 **
337 **	This looks a lot like getpwnam, except that it may want to
338 **	do some fancier pattern matching in /etc/passwd.
339 **
340 **	This routine contains most of the time of many sendmail runs.
341 **	It deserves to be optimized.
342 **
343 **	Parameters:
344 **		name -- the name to match against.
345 **
346 **	Returns:
347 **		A pointer to a pw struct.
348 **		NULL if name is unknown or ambiguous.
349 **
350 **	Side Effects:
351 **		may modify name.
352 */
353 
354 struct passwd *
355 finduser(name)
356 	char *name;
357 {
358 	register struct passwd *pw;
359 	register char *p;
360 	extern struct passwd *getpwent();
361 	extern struct passwd *getpwnam();
362 
363 	/* map upper => lower case */
364 	for (p = name; *p != '\0'; p++)
365 	{
366 		if (isascii(*p) && isupper(*p))
367 			*p = tolower(*p);
368 	}
369 
370 	/* look up this login name using fast path */
371 	if ((pw = getpwnam(name)) != NULL)
372 		return (pw);
373 
374 	/* search for a matching full name instead */
375 	for (p = name; *p != '\0'; p++)
376 	{
377 		if (*p == (SpaceSub & 0177) || *p == '_')
378 			*p = ' ';
379 	}
380 	(void) setpwent();
381 	while ((pw = getpwent()) != NULL)
382 	{
383 		char buf[MAXNAME];
384 
385 		buildfname(pw->pw_gecos, pw->pw_name, buf);
386 		if (index(buf, ' ') != NULL && !strcasecmp(buf, name))
387 		{
388 			message(Arpa_Info, "sending to login name %s", pw->pw_name);
389 			return (pw);
390 		}
391 	}
392 	return (NULL);
393 }
394 /*
395 **  WRITABLE -- predicate returning if the file is writable.
396 **
397 **	This routine must duplicate the algorithm in sys/fio.c.
398 **	Unfortunately, we cannot use the access call since we
399 **	won't necessarily be the real uid when we try to
400 **	actually open the file.
401 **
402 **	Notice that ANY file with ANY execute bit is automatically
403 **	not writable.  This is also enforced by mailfile.
404 **
405 **	Parameters:
406 **		s -- pointer to a stat struct for the file.
407 **
408 **	Returns:
409 **		TRUE -- if we will be able to write this file.
410 **		FALSE -- if we cannot write this file.
411 **
412 **	Side Effects:
413 **		none.
414 */
415 
416 bool
417 writable(s)
418 	register struct stat *s;
419 {
420 	int euid, egid;
421 	int bits;
422 
423 	if (bitset(0111, s->st_mode))
424 		return (FALSE);
425 	euid = getruid();
426 	egid = getrgid();
427 	if (geteuid() == 0)
428 	{
429 		if (bitset(S_ISUID, s->st_mode))
430 			euid = s->st_uid;
431 		if (bitset(S_ISGID, s->st_mode))
432 			egid = s->st_gid;
433 	}
434 
435 	if (euid == 0)
436 		return (TRUE);
437 	bits = S_IWRITE;
438 	if (euid != s->st_uid)
439 	{
440 		bits >>= 3;
441 		if (egid != s->st_gid)
442 			bits >>= 3;
443 	}
444 	return ((s->st_mode & bits) != 0);
445 }
446 /*
447 **  INCLUDE -- handle :include: specification.
448 **
449 **	Parameters:
450 **		fname -- filename to include.
451 **		msg -- message to print in verbose mode.
452 **		ctladdr -- address template to use to fill in these
453 **			addresses -- effective user/group id are
454 **			the important things.
455 **		sendq -- a pointer to the head of the send queue
456 **			to put these addresses in.
457 **
458 **	Returns:
459 **		none.
460 **
461 **	Side Effects:
462 **		reads the :include: file and sends to everyone
463 **		listed in that file.
464 */
465 
466 include(fname, msg, ctladdr, sendq)
467 	char *fname;
468 	char *msg;
469 	ADDRESS *ctladdr;
470 	ADDRESS **sendq;
471 {
472 	char buf[MAXLINE];
473 	register FILE *fp;
474 	char *oldto = CurEnv->e_to;
475 	char *oldfilename = FileName;
476 	int oldlinenumber = LineNumber;
477 
478 	fp = fopen(fname, "r");
479 	if (fp == NULL)
480 	{
481 		usrerr("Cannot open %s", fname);
482 		return;
483 	}
484 	if (getctladdr(ctladdr) == NULL)
485 	{
486 		struct stat st;
487 
488 		if (fstat(fileno(fp), &st) < 0)
489 			syserr("Cannot fstat %s!", fname);
490 		ctladdr->q_uid = st.st_uid;
491 		ctladdr->q_gid = st.st_gid;
492 		ctladdr->q_flags |= QGOODUID;
493 	}
494 
495 	/* read the file -- each line is a comma-separated list. */
496 	FileName = fname;
497 	LineNumber = 0;
498 	while (fgets(buf, sizeof buf, fp) != NULL)
499 	{
500 		register char *p = index(buf, '\n');
501 
502 		if (p != NULL)
503 			*p = '\0';
504 		if (buf[0] == '\0')
505 			continue;
506 		CurEnv->e_to = oldto;
507 		message(Arpa_Info, "%s to %s", msg, buf);
508 		AliasLevel++;
509 		sendtolist(buf, ctladdr, sendq);
510 		AliasLevel--;
511 	}
512 
513 	(void) fclose(fp);
514 	FileName = oldfilename;
515 	LineNumber = oldlinenumber;
516 }
517 /*
518 **  SENDTOARGV -- send to an argument vector.
519 **
520 **	Parameters:
521 **		argv -- argument vector to send to.
522 **
523 **	Returns:
524 **		none.
525 **
526 **	Side Effects:
527 **		puts all addresses on the argument vector onto the
528 **			send queue.
529 */
530 
531 sendtoargv(argv)
532 	register char **argv;
533 {
534 	register char *p;
535 
536 	while ((p = *argv++) != NULL)
537 	{
538 		if (argv[0] != NULL && argv[1] != NULL && !strcasecmp(argv[0], "at"))
539 		{
540 			char nbuf[MAXNAME];
541 
542 			if (strlen(p) + strlen(argv[1]) + 2 > sizeof nbuf)
543 				usrerr("address overflow");
544 			else
545 			{
546 				(void) strcpy(nbuf, p);
547 				(void) strcat(nbuf, "@");
548 				(void) strcat(nbuf, argv[1]);
549 				p = newstr(nbuf);
550 				argv += 2;
551 			}
552 		}
553 		sendtolist(p, (ADDRESS *) NULL, &CurEnv->e_sendqueue);
554 	}
555 }
556 /*
557 **  GETCTLADDR -- get controlling address from an address header.
558 **
559 **	If none, get one corresponding to the effective userid.
560 **
561 **	Parameters:
562 **		a -- the address to find the controller of.
563 **
564 **	Returns:
565 **		the controlling address.
566 **
567 **	Side Effects:
568 **		none.
569 */
570 
571 ADDRESS *
572 getctladdr(a)
573 	register ADDRESS *a;
574 {
575 	while (a != NULL && !bitset(QGOODUID, a->q_flags))
576 		a = a->q_alias;
577 	return (a);
578 }
579