xref: /freebsd/usr.bin/mail/names.c (revision a2f733abcff64628b7771a47089628b7327a88bd)
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 #endif /* not lint */
34 #include <sys/cdefs.h>
35 /*
36  * Mail -- a mail program
37  *
38  * Handle name lists.
39  */
40 
41 #include "rcv.h"
42 #include <fcntl.h>
43 #include "extern.h"
44 
45 /*
46  * Allocate a single element of a name list,
47  * initialize its name field to the passed
48  * name and return it.
49  */
50 struct name *
51 nalloc(char str[], int ntype)
52 {
53 	struct name *np;
54 
55 	np = (struct name *)salloc(sizeof(*np));
56 	np->n_flink = NULL;
57 	np->n_blink = NULL;
58 	np->n_type = ntype;
59 	np->n_name = savestr(str);
60 	return (np);
61 }
62 
63 /*
64  * Find the tail of a list and return it.
65  */
66 struct name *
67 tailof(struct name *name)
68 {
69 	struct name *np;
70 
71 	np = name;
72 	if (np == NULL)
73 		return (NULL);
74 	while (np->n_flink != NULL)
75 		np = np->n_flink;
76 	return (np);
77 }
78 
79 /*
80  * Extract a list of names from a line,
81  * and make a list of names from it.
82  * Return the list or NULL if none found.
83  */
84 struct name *
85 extract(char *line, int ntype)
86 {
87 	char *cp, *nbuf;
88 	struct name *top, *np, *t;
89 
90 	if (line == NULL || *line == '\0')
91 		return (NULL);
92 	if ((nbuf = malloc(strlen(line) + 1)) == NULL)
93 		err(1, "Out of memory");
94 	top = NULL;
95 	np = NULL;
96 	cp = line;
97 	while ((cp = yankword(cp, nbuf)) != NULL) {
98 		t = nalloc(nbuf, ntype);
99 		if (top == NULL)
100 			top = t;
101 		else
102 			np->n_flink = t;
103 		t->n_blink = np;
104 		np = t;
105 	}
106 	(void)free(nbuf);
107 	return (top);
108 }
109 
110 /*
111  * Turn a list of names into a string of the same names.
112  */
113 char *
114 detract(struct name *np, int ntype)
115 {
116 	int s, comma;
117 	char *cp, *top;
118 	struct name *p;
119 
120 	comma = ntype & GCOMMA;
121 	if (np == NULL)
122 		return (NULL);
123 	ntype &= ~GCOMMA;
124 	s = 0;
125 	if (debug && comma)
126 		fprintf(stderr, "detract asked to insert commas\n");
127 	for (p = np; p != NULL; p = p->n_flink) {
128 		if (ntype && (p->n_type & GMASK) != ntype)
129 			continue;
130 		s += strlen(p->n_name) + 1;
131 		if (comma)
132 			s++;
133 	}
134 	if (s == 0)
135 		return (NULL);
136 	s += 2;
137 	top = salloc(s);
138 	cp = top;
139 	for (p = np; p != NULL; p = p->n_flink) {
140 		if (ntype && (p->n_type & GMASK) != ntype)
141 			continue;
142 		cp += strlcpy(cp, p->n_name, strlen(p->n_name) + 1);
143 		if (comma && p->n_flink != NULL)
144 			*cp++ = ',';
145 		*cp++ = ' ';
146 	}
147 	*--cp = '\0';
148 	if (comma && *--cp == ',')
149 		*cp = '\0';
150 	return (top);
151 }
152 
153 /*
154  * Grab a single word (liberal word)
155  * Throw away things between ()'s, and take anything between <>.
156  */
157 char *
158 yankword(char *ap, char *wbuf)
159 {
160 	char *cp, *cp2;
161 
162 	cp = ap;
163 	for (;;) {
164 		if (*cp == '\0')
165 			return (NULL);
166 		if (*cp == '(') {
167 			int nesting = 0;
168 
169 			while (*cp != '\0') {
170 				switch (*cp++) {
171 				case '(':
172 					nesting++;
173 					break;
174 				case ')':
175 					--nesting;
176 					break;
177 				}
178 				if (nesting <= 0)
179 					break;
180 			}
181 		} else if (*cp == ' ' || *cp == '\t' || *cp == ',')
182 			cp++;
183 		else
184 			break;
185 	}
186 	if (*cp ==  '<')
187 		for (cp2 = wbuf; *cp && (*cp2++ = *cp++) != '>';)
188 			;
189 	else
190 		for (cp2 = wbuf; *cp != '\0' && strchr(" \t,(", *cp) == NULL;
191 		    *cp2++ = *cp++)
192 			;
193 	*cp2 = '\0';
194 	return (cp);
195 }
196 
197 /*
198  * Grab a single login name (liberal word)
199  * Throw away things between ()'s, take anything between <>,
200  * and look for words before metacharacters %, @, !.
201  */
202 char *
203 yanklogin(char *ap, char *wbuf)
204 {
205 	char *cp, *cp2, *cp_temp;
206 	int n;
207 
208 	cp = ap;
209 	for (;;) {
210 		if (*cp == '\0')
211 			return (NULL);
212 		if (*cp == '(') {
213 			int nesting = 0;
214 
215 			while (*cp != '\0') {
216 				switch (*cp++) {
217 				case '(':
218 					nesting++;
219 					break;
220 				case ')':
221 					--nesting;
222 					break;
223 				}
224 				if (nesting <= 0)
225 					break;
226 			}
227 		} else if (*cp == ' ' || *cp == '\t' || *cp == ',')
228 			cp++;
229 		else
230 			break;
231 	}
232 
233 	/*
234 	 * Now, let's go forward till we meet the needed character,
235 	 * and step one word back.
236 	 */
237 
238 	/* First, remember current point. */
239 	cp_temp = cp;
240 	n = 0;
241 
242 	/*
243 	 * Note that we look ahead in a cycle. This is safe, since
244 	 * non-end of string is checked first.
245 	 */
246 	while(*cp != '\0' && strchr("@%!", *(cp + 1)) == NULL)
247 		cp++;
248 
249 	/*
250 	 * Now, start stepping back to the first non-word character,
251 	 * while counting the number of symbols in a word.
252 	 */
253 	while(cp != cp_temp && strchr(" \t,<>", *(cp - 1)) == NULL) {
254 		n++;
255 		cp--;
256 	}
257 
258 	/* Finally, grab the word forward. */
259 	cp2 = wbuf;
260 	while(n >= 0) {
261 		*cp2++=*cp++;
262 		n--;
263 	}
264 
265 	*cp2 = '\0';
266 	return (cp);
267 }
268 
269 /*
270  * For each recipient in the passed name list with a /
271  * in the name, append the message to the end of the named file
272  * and remove him from the recipient list.
273  *
274  * Recipients whose name begins with | are piped through the given
275  * program and removed.
276  */
277 struct name *
278 outof(struct name *names, FILE *fo, struct header *hp)
279 {
280 	int c, ispipe;
281 	struct name *np, *top;
282 	time_t now;
283 	char *date, *fname;
284 	FILE *fout, *fin;
285 
286 	top = names;
287 	np = names;
288 	(void)time(&now);
289 	date = ctime(&now);
290 	while (np != NULL) {
291 		if (!isfileaddr(np->n_name) && np->n_name[0] != '|') {
292 			np = np->n_flink;
293 			continue;
294 		}
295 		ispipe = np->n_name[0] == '|';
296 		if (ispipe)
297 			fname = np->n_name+1;
298 		else
299 			fname = expand(np->n_name);
300 
301 		/*
302 		 * See if we have copied the complete message out yet.
303 		 * If not, do so.
304 		 */
305 
306 		if (image < 0) {
307 			int fd;
308 			char tempname[PATHSIZE];
309 
310 			(void)snprintf(tempname, sizeof(tempname),
311 			    "%s/mail.ReXXXXXXXXXX", tmpdir);
312 			if ((fd = mkstemp(tempname)) == -1 ||
313 			    (fout = Fdopen(fd, "a")) == NULL) {
314 				warn("%s", tempname);
315 				senderr++;
316 				goto cant;
317 			}
318 			image = open(tempname, O_RDWR);
319 			(void)rm(tempname);
320 			if (image < 0) {
321 				warn("%s", tempname);
322 				senderr++;
323 				(void)Fclose(fout);
324 				goto cant;
325 			}
326 			(void)fcntl(image, F_SETFD, 1);
327 			fprintf(fout, "From %s %s", myname, date);
328 			puthead(hp, fout,
329 			    GTO|GSUBJECT|GCC|GREPLYTO|GINREPLYTO|GNL);
330 			while ((c = getc(fo)) != EOF)
331 				(void)putc(c, fout);
332 			rewind(fo);
333 			fprintf(fout, "\n");
334 			(void)fflush(fout);
335 			if (ferror(fout)) {
336 				warn("%s", tempname);
337 				senderr++;
338 				(void)Fclose(fout);
339 				goto cant;
340 			}
341 			(void)Fclose(fout);
342 		}
343 
344 		/*
345 		 * Now either copy "image" to the desired file
346 		 * or give it as the standard input to the desired
347 		 * program as appropriate.
348 		 */
349 
350 		if (ispipe) {
351 			int pid;
352 			char *sh;
353 			sigset_t nset;
354 
355 			/*
356 			 * XXX
357 			 * We can't really reuse the same image file,
358 			 * because multiple piped recipients will
359 			 * share the same lseek location and trample
360 			 * on one another.
361 			 */
362 			if ((sh = value("SHELL")) == NULL)
363 				sh = _PATH_CSHELL;
364 			(void)sigemptyset(&nset);
365 			(void)sigaddset(&nset, SIGHUP);
366 			(void)sigaddset(&nset, SIGINT);
367 			(void)sigaddset(&nset, SIGQUIT);
368 			pid = start_command(sh, &nset, image, -1, "-c", fname,
369 			    NULL);
370 			if (pid < 0) {
371 				senderr++;
372 				goto cant;
373 			}
374 			free_child(pid);
375 		} else {
376 			int f;
377 			if ((fout = Fopen(fname, "a")) == NULL) {
378 				warn("%s", fname);
379 				senderr++;
380 				goto cant;
381 			}
382 			if ((f = dup(image)) < 0) {
383 				warn("dup");
384 				fin = NULL;
385 			} else
386 				fin = Fdopen(f, "r");
387 			if (fin == NULL) {
388 				fprintf(stderr, "Can't reopen image\n");
389 				(void)Fclose(fout);
390 				senderr++;
391 				goto cant;
392 			}
393 			rewind(fin);
394 			while ((c = getc(fin)) != EOF)
395 				(void)putc(c, fout);
396 			if (ferror(fout)) {
397 				warnx("%s", fname);
398 				senderr++;
399 				(void)Fclose(fout);
400 				(void)Fclose(fin);
401 				goto cant;
402 			}
403 			(void)Fclose(fout);
404 			(void)Fclose(fin);
405 		}
406 cant:
407 		/*
408 		 * In days of old we removed the entry from the
409 		 * the list; now for sake of header expansion
410 		 * we leave it in and mark it as deleted.
411 		 */
412 		np->n_type |= GDEL;
413 		np = np->n_flink;
414 	}
415 	if (image >= 0) {
416 		(void)close(image);
417 		image = -1;
418 	}
419 	return (top);
420 }
421 
422 /*
423  * Determine if the passed address is a local "send to file" address.
424  * If any of the network metacharacters precedes any slashes, it can't
425  * be a filename.  We cheat with .'s to allow path names like ./...
426  */
427 int
428 isfileaddr(char *name)
429 {
430 	char *cp;
431 
432 	if (*name == '+')
433 		return (1);
434 	for (cp = name; *cp != '\0'; cp++) {
435 		if (*cp == '!' || *cp == '%' || *cp == '@')
436 			return (0);
437 		if (*cp == '/')
438 			return (1);
439 	}
440 	return (0);
441 }
442 
443 /*
444  * Map all of the aliased users in the invoker's mailrc
445  * file and insert them into the list.
446  * Changed after all these months of service to recursively
447  * expand names (2/14/80).
448  */
449 
450 struct name *
451 usermap(struct name *names)
452 {
453 	struct name *new, *np, *cp;
454 	struct grouphead *gh;
455 	int metoo;
456 
457 	new = NULL;
458 	np = names;
459 	metoo = (value("metoo") != NULL);
460 	while (np != NULL) {
461 		if (np->n_name[0] == '\\') {
462 			cp = np->n_flink;
463 			new = put(new, np);
464 			np = cp;
465 			continue;
466 		}
467 		gh = findgroup(np->n_name);
468 		cp = np->n_flink;
469 		if (gh != NULL)
470 			new = gexpand(new, gh, metoo, np->n_type);
471 		else
472 			new = put(new, np);
473 		np = cp;
474 	}
475 	return (new);
476 }
477 
478 /*
479  * Recursively expand a group name.  We limit the expansion to some
480  * fixed level to keep things from going haywire.
481  * Direct recursion is not expanded for convenience.
482  */
483 
484 struct name *
485 gexpand(struct name *nlist, struct grouphead *gh, int metoo, int ntype)
486 {
487 	struct group *gp;
488 	struct grouphead *ngh;
489 	struct name *np;
490 	static int depth;
491 	char *cp;
492 
493 	if (depth > MAXEXP) {
494 		printf("Expanding alias to depth larger than %d\n", MAXEXP);
495 		return (nlist);
496 	}
497 	depth++;
498 	for (gp = gh->g_list; gp != NULL; gp = gp->ge_link) {
499 		cp = gp->ge_name;
500 		if (*cp == '\\')
501 			goto quote;
502 		if (strcmp(cp, gh->g_name) == 0)
503 			goto quote;
504 		if ((ngh = findgroup(cp)) != NULL) {
505 			nlist = gexpand(nlist, ngh, metoo, ntype);
506 			continue;
507 		}
508 quote:
509 		np = nalloc(cp, ntype);
510 		/*
511 		 * At this point should allow to expand
512 		 * to self if only person in group
513 		 */
514 		if (gp == gh->g_list && gp->ge_link == NULL)
515 			goto skip;
516 		if (!metoo && strcmp(cp, myname) == 0)
517 			np->n_type |= GDEL;
518 skip:
519 		nlist = put(nlist, np);
520 	}
521 	depth--;
522 	return (nlist);
523 }
524 
525 /*
526  * Concatenate the two passed name lists, return the result.
527  */
528 struct name *
529 cat(struct name *n1, struct name *n2)
530 {
531 	struct name *tail;
532 
533 	if (n1 == NULL)
534 		return (n2);
535 	if (n2 == NULL)
536 		return (n1);
537 	tail = tailof(n1);
538 	tail->n_flink = n2;
539 	n2->n_blink = tail;
540 	return (n1);
541 }
542 
543 /*
544  * Unpack the name list onto a vector of strings.
545  * Return an error if the name list won't fit.
546  */
547 char **
548 unpack(struct name *np)
549 {
550 	char **ap, **top;
551 	struct name *n;
552 	int t, extra, metoo, verbose;
553 
554 	n = np;
555 	if ((t = count(n)) == 0)
556 		errx(1, "No names to unpack");
557 	/*
558 	 * Compute the number of extra arguments we will need.
559 	 * We need at least two extra -- one for "mail" and one for
560 	 * the terminating 0 pointer.  Additional spots may be needed
561 	 * to pass along -f to the host mailer.
562 	 */
563 	extra = 2;
564 	extra++;
565 	metoo = value("metoo") != NULL;
566 	if (metoo)
567 		extra++;
568 	verbose = value("verbose") != NULL;
569 	if (verbose)
570 		extra++;
571 	top = (char **)salloc((t + extra) * sizeof(*top));
572 	ap = top;
573 	*ap++ = "sendmail";
574 	*ap++ = "-i";
575 	if (metoo)
576 		*ap++ = "-m";
577 	if (verbose)
578 		*ap++ = "-v";
579 	for (; n != NULL; n = n->n_flink)
580 		if ((n->n_type & GDEL) == 0)
581 			*ap++ = n->n_name;
582 	*ap = NULL;
583 	return (top);
584 }
585 
586 /*
587  * Remove all of the duplicates from the passed name list by
588  * insertion sorting them, then checking for dups.
589  * Return the head of the new list.
590  */
591 struct name *
592 elide(struct name *names)
593 {
594 	struct name *np, *t, *new;
595 	struct name *x;
596 
597 	if (names == NULL)
598 		return (NULL);
599 	new = names;
600 	np = names;
601 	np = np->n_flink;
602 	if (np != NULL)
603 		np->n_blink = NULL;
604 	new->n_flink = NULL;
605 	while (np != NULL) {
606 		t = new;
607 		while (strcasecmp(t->n_name, np->n_name) < 0) {
608 			if (t->n_flink == NULL)
609 				break;
610 			t = t->n_flink;
611 		}
612 
613 		/*
614 		 * If we ran out of t's, put the new entry after
615 		 * the current value of t.
616 		 */
617 
618 		if (strcasecmp(t->n_name, np->n_name) < 0) {
619 			t->n_flink = np;
620 			np->n_blink = t;
621 			t = np;
622 			np = np->n_flink;
623 			t->n_flink = NULL;
624 			continue;
625 		}
626 
627 		/*
628 		 * Otherwise, put the new entry in front of the
629 		 * current t.  If at the front of the list,
630 		 * the new guy becomes the new head of the list.
631 		 */
632 
633 		if (t == new) {
634 			t = np;
635 			np = np->n_flink;
636 			t->n_flink = new;
637 			new->n_blink = t;
638 			t->n_blink = NULL;
639 			new = t;
640 			continue;
641 		}
642 
643 		/*
644 		 * The normal case -- we are inserting into the
645 		 * middle of the list.
646 		 */
647 
648 		x = np;
649 		np = np->n_flink;
650 		x->n_flink = t;
651 		x->n_blink = t->n_blink;
652 		t->n_blink->n_flink = x;
653 		t->n_blink = x;
654 	}
655 
656 	/*
657 	 * Now the list headed up by new is sorted.
658 	 * Go through it and remove duplicates.
659 	 */
660 
661 	np = new;
662 	while (np != NULL) {
663 		t = np;
664 		while (t->n_flink != NULL &&
665 		    strcasecmp(np->n_name, t->n_flink->n_name) == 0)
666 			t = t->n_flink;
667 		if (t == np || t == NULL) {
668 			np = np->n_flink;
669 			continue;
670 		}
671 
672 		/*
673 		 * Now t points to the last entry with the same name
674 		 * as np.  Make np point beyond t.
675 		 */
676 
677 		np->n_flink = t->n_flink;
678 		if (t->n_flink != NULL)
679 			t->n_flink->n_blink = np;
680 		np = np->n_flink;
681 	}
682 	return (new);
683 }
684 
685 /*
686  * Put another node onto a list of names and return
687  * the list.
688  */
689 struct name *
690 put(struct name *list, struct name *node)
691 {
692 	node->n_flink = list;
693 	node->n_blink = NULL;
694 	if (list != NULL)
695 		list->n_blink = node;
696 	return (node);
697 }
698 
699 /*
700  * Determine the number of undeleted elements in
701  * a name list and return it.
702  */
703 int
704 count(struct name *np)
705 {
706 	int c;
707 
708 	for (c = 0; np != NULL; np = np->n_flink)
709 		if ((np->n_type & GDEL) == 0)
710 			c++;
711 	return (c);
712 }
713 
714 /*
715  * Delete the given name from a namelist.
716  */
717 struct name *
718 delname(struct name *np, char name[])
719 {
720 	struct name *p;
721 
722 	for (p = np; p != NULL; p = p->n_flink)
723 		if (strcasecmp(p->n_name, name) == 0) {
724 			if (p->n_blink == NULL) {
725 				if (p->n_flink != NULL)
726 					p->n_flink->n_blink = NULL;
727 				np = p->n_flink;
728 				continue;
729 			}
730 			if (p->n_flink == NULL) {
731 				if (p->n_blink != NULL)
732 					p->n_blink->n_flink = NULL;
733 				continue;
734 			}
735 			p->n_blink->n_flink = p->n_flink;
736 			p->n_flink->n_blink = p->n_blink;
737 		}
738 	return (np);
739 }
740 
741 /*
742  * Pretty print a name list
743  * Uncomment it if you need it.
744  */
745 
746 /*
747 void
748 prettyprint(struct name *name)
749 {
750 	struct name *np;
751 
752 	np = name;
753 	while (np != NULL) {
754 		fprintf(stderr, "%s(%d) ", np->n_name, np->n_type);
755 		np = np->n_flink;
756 	}
757 	fprintf(stderr, "\n");
758 }
759 */
760