xref: /freebsd/usr.bin/mail/names.c (revision 315ee00f)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1980, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #ifndef lint
33 #if 0
34 static char sccsid[] = "@(#)names.c	8.1 (Berkeley) 6/6/93";
35 #endif
36 #endif /* not lint */
37 #include <sys/cdefs.h>
38 /*
39  * Mail -- a mail program
40  *
41  * Handle name lists.
42  */
43 
44 #include "rcv.h"
45 #include <fcntl.h>
46 #include "extern.h"
47 
48 /*
49  * Allocate a single element of a name list,
50  * initialize its name field to the passed
51  * name and return it.
52  */
53 struct name *
54 nalloc(char str[], int ntype)
55 {
56 	struct name *np;
57 
58 	np = (struct name *)salloc(sizeof(*np));
59 	np->n_flink = NULL;
60 	np->n_blink = NULL;
61 	np->n_type = ntype;
62 	np->n_name = savestr(str);
63 	return (np);
64 }
65 
66 /*
67  * Find the tail of a list and return it.
68  */
69 struct name *
70 tailof(struct name *name)
71 {
72 	struct name *np;
73 
74 	np = name;
75 	if (np == NULL)
76 		return (NULL);
77 	while (np->n_flink != NULL)
78 		np = np->n_flink;
79 	return (np);
80 }
81 
82 /*
83  * Extract a list of names from a line,
84  * and make a list of names from it.
85  * Return the list or NULL if none found.
86  */
87 struct name *
88 extract(char *line, int ntype)
89 {
90 	char *cp, *nbuf;
91 	struct name *top, *np, *t;
92 
93 	if (line == NULL || *line == '\0')
94 		return (NULL);
95 	if ((nbuf = malloc(strlen(line) + 1)) == NULL)
96 		err(1, "Out of memory");
97 	top = NULL;
98 	np = NULL;
99 	cp = line;
100 	while ((cp = yankword(cp, nbuf)) != NULL) {
101 		t = nalloc(nbuf, ntype);
102 		if (top == NULL)
103 			top = t;
104 		else
105 			np->n_flink = t;
106 		t->n_blink = np;
107 		np = t;
108 	}
109 	(void)free(nbuf);
110 	return (top);
111 }
112 
113 /*
114  * Turn a list of names into a string of the same names.
115  */
116 char *
117 detract(struct name *np, int ntype)
118 {
119 	int s, comma;
120 	char *cp, *top;
121 	struct name *p;
122 
123 	comma = ntype & GCOMMA;
124 	if (np == NULL)
125 		return (NULL);
126 	ntype &= ~GCOMMA;
127 	s = 0;
128 	if (debug && comma)
129 		fprintf(stderr, "detract asked to insert commas\n");
130 	for (p = np; p != NULL; p = p->n_flink) {
131 		if (ntype && (p->n_type & GMASK) != ntype)
132 			continue;
133 		s += strlen(p->n_name) + 1;
134 		if (comma)
135 			s++;
136 	}
137 	if (s == 0)
138 		return (NULL);
139 	s += 2;
140 	top = salloc(s);
141 	cp = top;
142 	for (p = np; p != NULL; p = p->n_flink) {
143 		if (ntype && (p->n_type & GMASK) != ntype)
144 			continue;
145 		cp += strlcpy(cp, p->n_name, strlen(p->n_name) + 1);
146 		if (comma && p->n_flink != NULL)
147 			*cp++ = ',';
148 		*cp++ = ' ';
149 	}
150 	*--cp = '\0';
151 	if (comma && *--cp == ',')
152 		*cp = '\0';
153 	return (top);
154 }
155 
156 /*
157  * Grab a single word (liberal word)
158  * Throw away things between ()'s, and take anything between <>.
159  */
160 char *
161 yankword(char *ap, char *wbuf)
162 {
163 	char *cp, *cp2;
164 
165 	cp = ap;
166 	for (;;) {
167 		if (*cp == '\0')
168 			return (NULL);
169 		if (*cp == '(') {
170 			int nesting = 0;
171 
172 			while (*cp != '\0') {
173 				switch (*cp++) {
174 				case '(':
175 					nesting++;
176 					break;
177 				case ')':
178 					--nesting;
179 					break;
180 				}
181 				if (nesting <= 0)
182 					break;
183 			}
184 		} else if (*cp == ' ' || *cp == '\t' || *cp == ',')
185 			cp++;
186 		else
187 			break;
188 	}
189 	if (*cp ==  '<')
190 		for (cp2 = wbuf; *cp && (*cp2++ = *cp++) != '>';)
191 			;
192 	else
193 		for (cp2 = wbuf; *cp != '\0' && strchr(" \t,(", *cp) == NULL;
194 		    *cp2++ = *cp++)
195 			;
196 	*cp2 = '\0';
197 	return (cp);
198 }
199 
200 /*
201  * Grab a single login name (liberal word)
202  * Throw away things between ()'s, take anything between <>,
203  * and look for words before metacharacters %, @, !.
204  */
205 char *
206 yanklogin(char *ap, char *wbuf)
207 {
208 	char *cp, *cp2, *cp_temp;
209 	int n;
210 
211 	cp = ap;
212 	for (;;) {
213 		if (*cp == '\0')
214 			return (NULL);
215 		if (*cp == '(') {
216 			int nesting = 0;
217 
218 			while (*cp != '\0') {
219 				switch (*cp++) {
220 				case '(':
221 					nesting++;
222 					break;
223 				case ')':
224 					--nesting;
225 					break;
226 				}
227 				if (nesting <= 0)
228 					break;
229 			}
230 		} else if (*cp == ' ' || *cp == '\t' || *cp == ',')
231 			cp++;
232 		else
233 			break;
234 	}
235 
236 	/*
237 	 * Now, let's go forward till we meet the needed character,
238 	 * and step one word back.
239 	 */
240 
241 	/* First, remember current point. */
242 	cp_temp = cp;
243 	n = 0;
244 
245 	/*
246 	 * Note that we look ahead in a cycle. This is safe, since
247 	 * non-end of string is checked first.
248 	 */
249 	while(*cp != '\0' && strchr("@%!", *(cp + 1)) == NULL)
250 		cp++;
251 
252 	/*
253 	 * Now, start stepping back to the first non-word character,
254 	 * while counting the number of symbols in a word.
255 	 */
256 	while(cp != cp_temp && strchr(" \t,<>", *(cp - 1)) == NULL) {
257 		n++;
258 		cp--;
259 	}
260 
261 	/* Finally, grab the word forward. */
262 	cp2 = wbuf;
263 	while(n >= 0) {
264 		*cp2++=*cp++;
265 		n--;
266 	}
267 
268 	*cp2 = '\0';
269 	return (cp);
270 }
271 
272 /*
273  * For each recipient in the passed name list with a /
274  * in the name, append the message to the end of the named file
275  * and remove him from the recipient list.
276  *
277  * Recipients whose name begins with | are piped through the given
278  * program and removed.
279  */
280 struct name *
281 outof(struct name *names, FILE *fo, struct header *hp)
282 {
283 	int c, ispipe;
284 	struct name *np, *top;
285 	time_t now;
286 	char *date, *fname;
287 	FILE *fout, *fin;
288 
289 	top = names;
290 	np = names;
291 	(void)time(&now);
292 	date = ctime(&now);
293 	while (np != NULL) {
294 		if (!isfileaddr(np->n_name) && np->n_name[0] != '|') {
295 			np = np->n_flink;
296 			continue;
297 		}
298 		ispipe = np->n_name[0] == '|';
299 		if (ispipe)
300 			fname = np->n_name+1;
301 		else
302 			fname = expand(np->n_name);
303 
304 		/*
305 		 * See if we have copied the complete message out yet.
306 		 * If not, do so.
307 		 */
308 
309 		if (image < 0) {
310 			int fd;
311 			char tempname[PATHSIZE];
312 
313 			(void)snprintf(tempname, sizeof(tempname),
314 			    "%s/mail.ReXXXXXXXXXX", tmpdir);
315 			if ((fd = mkstemp(tempname)) == -1 ||
316 			    (fout = Fdopen(fd, "a")) == NULL) {
317 				warn("%s", tempname);
318 				senderr++;
319 				goto cant;
320 			}
321 			image = open(tempname, O_RDWR);
322 			(void)rm(tempname);
323 			if (image < 0) {
324 				warn("%s", tempname);
325 				senderr++;
326 				(void)Fclose(fout);
327 				goto cant;
328 			}
329 			(void)fcntl(image, F_SETFD, 1);
330 			fprintf(fout, "From %s %s", myname, date);
331 			puthead(hp, fout,
332 			    GTO|GSUBJECT|GCC|GREPLYTO|GINREPLYTO|GNL);
333 			while ((c = getc(fo)) != EOF)
334 				(void)putc(c, fout);
335 			rewind(fo);
336 			fprintf(fout, "\n");
337 			(void)fflush(fout);
338 			if (ferror(fout)) {
339 				warn("%s", tempname);
340 				senderr++;
341 				(void)Fclose(fout);
342 				goto cant;
343 			}
344 			(void)Fclose(fout);
345 		}
346 
347 		/*
348 		 * Now either copy "image" to the desired file
349 		 * or give it as the standard input to the desired
350 		 * program as appropriate.
351 		 */
352 
353 		if (ispipe) {
354 			int pid;
355 			char *sh;
356 			sigset_t nset;
357 
358 			/*
359 			 * XXX
360 			 * We can't really reuse the same image file,
361 			 * because multiple piped recipients will
362 			 * share the same lseek location and trample
363 			 * on one another.
364 			 */
365 			if ((sh = value("SHELL")) == NULL)
366 				sh = _PATH_CSHELL;
367 			(void)sigemptyset(&nset);
368 			(void)sigaddset(&nset, SIGHUP);
369 			(void)sigaddset(&nset, SIGINT);
370 			(void)sigaddset(&nset, SIGQUIT);
371 			pid = start_command(sh, &nset, image, -1, "-c", fname,
372 			    NULL);
373 			if (pid < 0) {
374 				senderr++;
375 				goto cant;
376 			}
377 			free_child(pid);
378 		} else {
379 			int f;
380 			if ((fout = Fopen(fname, "a")) == NULL) {
381 				warn("%s", fname);
382 				senderr++;
383 				goto cant;
384 			}
385 			if ((f = dup(image)) < 0) {
386 				warn("dup");
387 				fin = NULL;
388 			} else
389 				fin = Fdopen(f, "r");
390 			if (fin == NULL) {
391 				fprintf(stderr, "Can't reopen image\n");
392 				(void)Fclose(fout);
393 				senderr++;
394 				goto cant;
395 			}
396 			rewind(fin);
397 			while ((c = getc(fin)) != EOF)
398 				(void)putc(c, fout);
399 			if (ferror(fout)) {
400 				warnx("%s", fname);
401 				senderr++;
402 				(void)Fclose(fout);
403 				(void)Fclose(fin);
404 				goto cant;
405 			}
406 			(void)Fclose(fout);
407 			(void)Fclose(fin);
408 		}
409 cant:
410 		/*
411 		 * In days of old we removed the entry from the
412 		 * the list; now for sake of header expansion
413 		 * we leave it in and mark it as deleted.
414 		 */
415 		np->n_type |= GDEL;
416 		np = np->n_flink;
417 	}
418 	if (image >= 0) {
419 		(void)close(image);
420 		image = -1;
421 	}
422 	return (top);
423 }
424 
425 /*
426  * Determine if the passed address is a local "send to file" address.
427  * If any of the network metacharacters precedes any slashes, it can't
428  * be a filename.  We cheat with .'s to allow path names like ./...
429  */
430 int
431 isfileaddr(char *name)
432 {
433 	char *cp;
434 
435 	if (*name == '+')
436 		return (1);
437 	for (cp = name; *cp != '\0'; cp++) {
438 		if (*cp == '!' || *cp == '%' || *cp == '@')
439 			return (0);
440 		if (*cp == '/')
441 			return (1);
442 	}
443 	return (0);
444 }
445 
446 /*
447  * Map all of the aliased users in the invoker's mailrc
448  * file and insert them into the list.
449  * Changed after all these months of service to recursively
450  * expand names (2/14/80).
451  */
452 
453 struct name *
454 usermap(struct name *names)
455 {
456 	struct name *new, *np, *cp;
457 	struct grouphead *gh;
458 	int metoo;
459 
460 	new = NULL;
461 	np = names;
462 	metoo = (value("metoo") != NULL);
463 	while (np != NULL) {
464 		if (np->n_name[0] == '\\') {
465 			cp = np->n_flink;
466 			new = put(new, np);
467 			np = cp;
468 			continue;
469 		}
470 		gh = findgroup(np->n_name);
471 		cp = np->n_flink;
472 		if (gh != NULL)
473 			new = gexpand(new, gh, metoo, np->n_type);
474 		else
475 			new = put(new, np);
476 		np = cp;
477 	}
478 	return (new);
479 }
480 
481 /*
482  * Recursively expand a group name.  We limit the expansion to some
483  * fixed level to keep things from going haywire.
484  * Direct recursion is not expanded for convenience.
485  */
486 
487 struct name *
488 gexpand(struct name *nlist, struct grouphead *gh, int metoo, int ntype)
489 {
490 	struct group *gp;
491 	struct grouphead *ngh;
492 	struct name *np;
493 	static int depth;
494 	char *cp;
495 
496 	if (depth > MAXEXP) {
497 		printf("Expanding alias to depth larger than %d\n", MAXEXP);
498 		return (nlist);
499 	}
500 	depth++;
501 	for (gp = gh->g_list; gp != NULL; gp = gp->ge_link) {
502 		cp = gp->ge_name;
503 		if (*cp == '\\')
504 			goto quote;
505 		if (strcmp(cp, gh->g_name) == 0)
506 			goto quote;
507 		if ((ngh = findgroup(cp)) != NULL) {
508 			nlist = gexpand(nlist, ngh, metoo, ntype);
509 			continue;
510 		}
511 quote:
512 		np = nalloc(cp, ntype);
513 		/*
514 		 * At this point should allow to expand
515 		 * to self if only person in group
516 		 */
517 		if (gp == gh->g_list && gp->ge_link == NULL)
518 			goto skip;
519 		if (!metoo && strcmp(cp, myname) == 0)
520 			np->n_type |= GDEL;
521 skip:
522 		nlist = put(nlist, np);
523 	}
524 	depth--;
525 	return (nlist);
526 }
527 
528 /*
529  * Concatenate the two passed name lists, return the result.
530  */
531 struct name *
532 cat(struct name *n1, struct name *n2)
533 {
534 	struct name *tail;
535 
536 	if (n1 == NULL)
537 		return (n2);
538 	if (n2 == NULL)
539 		return (n1);
540 	tail = tailof(n1);
541 	tail->n_flink = n2;
542 	n2->n_blink = tail;
543 	return (n1);
544 }
545 
546 /*
547  * Unpack the name list onto a vector of strings.
548  * Return an error if the name list won't fit.
549  */
550 char **
551 unpack(struct name *np)
552 {
553 	char **ap, **top;
554 	struct name *n;
555 	int t, extra, metoo, verbose;
556 
557 	n = np;
558 	if ((t = count(n)) == 0)
559 		errx(1, "No names to unpack");
560 	/*
561 	 * Compute the number of extra arguments we will need.
562 	 * We need at least two extra -- one for "mail" and one for
563 	 * the terminating 0 pointer.  Additional spots may be needed
564 	 * to pass along -f to the host mailer.
565 	 */
566 	extra = 2;
567 	extra++;
568 	metoo = value("metoo") != NULL;
569 	if (metoo)
570 		extra++;
571 	verbose = value("verbose") != NULL;
572 	if (verbose)
573 		extra++;
574 	top = (char **)salloc((t + extra) * sizeof(*top));
575 	ap = top;
576 	*ap++ = "sendmail";
577 	*ap++ = "-i";
578 	if (metoo)
579 		*ap++ = "-m";
580 	if (verbose)
581 		*ap++ = "-v";
582 	for (; n != NULL; n = n->n_flink)
583 		if ((n->n_type & GDEL) == 0)
584 			*ap++ = n->n_name;
585 	*ap = NULL;
586 	return (top);
587 }
588 
589 /*
590  * Remove all of the duplicates from the passed name list by
591  * insertion sorting them, then checking for dups.
592  * Return the head of the new list.
593  */
594 struct name *
595 elide(struct name *names)
596 {
597 	struct name *np, *t, *new;
598 	struct name *x;
599 
600 	if (names == NULL)
601 		return (NULL);
602 	new = names;
603 	np = names;
604 	np = np->n_flink;
605 	if (np != NULL)
606 		np->n_blink = NULL;
607 	new->n_flink = NULL;
608 	while (np != NULL) {
609 		t = new;
610 		while (strcasecmp(t->n_name, np->n_name) < 0) {
611 			if (t->n_flink == NULL)
612 				break;
613 			t = t->n_flink;
614 		}
615 
616 		/*
617 		 * If we ran out of t's, put the new entry after
618 		 * the current value of t.
619 		 */
620 
621 		if (strcasecmp(t->n_name, np->n_name) < 0) {
622 			t->n_flink = np;
623 			np->n_blink = t;
624 			t = np;
625 			np = np->n_flink;
626 			t->n_flink = NULL;
627 			continue;
628 		}
629 
630 		/*
631 		 * Otherwise, put the new entry in front of the
632 		 * current t.  If at the front of the list,
633 		 * the new guy becomes the new head of the list.
634 		 */
635 
636 		if (t == new) {
637 			t = np;
638 			np = np->n_flink;
639 			t->n_flink = new;
640 			new->n_blink = t;
641 			t->n_blink = NULL;
642 			new = t;
643 			continue;
644 		}
645 
646 		/*
647 		 * The normal case -- we are inserting into the
648 		 * middle of the list.
649 		 */
650 
651 		x = np;
652 		np = np->n_flink;
653 		x->n_flink = t;
654 		x->n_blink = t->n_blink;
655 		t->n_blink->n_flink = x;
656 		t->n_blink = x;
657 	}
658 
659 	/*
660 	 * Now the list headed up by new is sorted.
661 	 * Go through it and remove duplicates.
662 	 */
663 
664 	np = new;
665 	while (np != NULL) {
666 		t = np;
667 		while (t->n_flink != NULL &&
668 		    strcasecmp(np->n_name, t->n_flink->n_name) == 0)
669 			t = t->n_flink;
670 		if (t == np || t == NULL) {
671 			np = np->n_flink;
672 			continue;
673 		}
674 
675 		/*
676 		 * Now t points to the last entry with the same name
677 		 * as np.  Make np point beyond t.
678 		 */
679 
680 		np->n_flink = t->n_flink;
681 		if (t->n_flink != NULL)
682 			t->n_flink->n_blink = np;
683 		np = np->n_flink;
684 	}
685 	return (new);
686 }
687 
688 /*
689  * Put another node onto a list of names and return
690  * the list.
691  */
692 struct name *
693 put(struct name *list, struct name *node)
694 {
695 	node->n_flink = list;
696 	node->n_blink = NULL;
697 	if (list != NULL)
698 		list->n_blink = node;
699 	return (node);
700 }
701 
702 /*
703  * Determine the number of undeleted elements in
704  * a name list and return it.
705  */
706 int
707 count(struct name *np)
708 {
709 	int c;
710 
711 	for (c = 0; np != NULL; np = np->n_flink)
712 		if ((np->n_type & GDEL) == 0)
713 			c++;
714 	return (c);
715 }
716 
717 /*
718  * Delete the given name from a namelist.
719  */
720 struct name *
721 delname(struct name *np, char name[])
722 {
723 	struct name *p;
724 
725 	for (p = np; p != NULL; p = p->n_flink)
726 		if (strcasecmp(p->n_name, name) == 0) {
727 			if (p->n_blink == NULL) {
728 				if (p->n_flink != NULL)
729 					p->n_flink->n_blink = NULL;
730 				np = p->n_flink;
731 				continue;
732 			}
733 			if (p->n_flink == NULL) {
734 				if (p->n_blink != NULL)
735 					p->n_blink->n_flink = NULL;
736 				continue;
737 			}
738 			p->n_blink->n_flink = p->n_flink;
739 			p->n_flink->n_blink = p->n_blink;
740 		}
741 	return (np);
742 }
743 
744 /*
745  * Pretty print a name list
746  * Uncomment it if you need it.
747  */
748 
749 /*
750 void
751 prettyprint(struct name *name)
752 {
753 	struct name *np;
754 
755 	np = name;
756 	while (np != NULL) {
757 		fprintf(stderr, "%s(%d) ", np->n_name, np->n_type);
758 		np = np->n_flink;
759 	}
760 	fprintf(stderr, "\n");
761 }
762 */
763