1 /*
2  * Copyright (c) 2021 Omar Polo <op@omarpolo.com>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include "compat.h"
18 
19 #include <sys/socket.h>
20 #include <sys/wait.h>
21 
22 #include <errno.h>
23 #include <getopt.h>
24 #include <signal.h>
25 #include <stdio.h>
26 #include <stdlib.h>
27 #include <string.h>
28 #include <unistd.h>
29 
30 #include "defaults.h"
31 #include "fs.h"
32 #include "minibuffer.h"
33 #include "parser.h"
34 #include "session.h"
35 #include "telescope.h"
36 #include "ui.h"
37 
38 static struct option longopts[] = {
39 	{"colors",	no_argument,	NULL,	'c'},
40 	{"help",	no_argument,	NULL,	'h'},
41 	{"safe",	no_argument,	NULL,	'S'},
42 	{"version",	no_argument,	NULL,	'v'},
43 	{NULL,		0,		NULL,	0},
44 };
45 
46 static const char *opts = "Cc:hnST:v";
47 
48 static int	has_url;
49 static char	url[GEMINI_URL_LEN];
50 
51 /*
52  * Used to know when we're finished loading.
53  */
54 int			 operating;
55 
56 /*
57  * "Safe" (or "sandobox") mode.  If enabled, Telescope shouldn't write
58  * anything to the filesystem or execute external programs.
59  */
60 int			safe_mode;
61 
62 static struct imsgev	*iev_fs, *iev_net;
63 
64 struct tabshead		 tabshead = TAILQ_HEAD_INITIALIZER(tabshead);
65 struct proxylist	 proxies = TAILQ_HEAD_INITIALIZER(proxies);
66 
67 enum telescope_process {
68 	PROC_UI,
69 	PROC_FS,
70 	PROC_NET,
71 };
72 
73 #define CANNOT_FETCH		0
74 #define TOO_MUCH_REDIRECTS	1
75 #define MALFORMED_RESPONSE	2
76 #define UNKNOWN_TYPE_OR_CSET	3
77 #define UNKNOWN_PROTOCOL	4
78 
79 /* XXX: keep in sync with normalize_code */
80 const char *err_pages[70] = {
81 	[CANNOT_FETCH]		= "# Couldn't load the page\n",
82 	[TOO_MUCH_REDIRECTS]	= "# Too much redirects\n",
83 	[MALFORMED_RESPONSE]	= "# Got a malformed response\n",
84 	[UNKNOWN_TYPE_OR_CSET]	= "# Unsupported type or charset\n",
85 	[UNKNOWN_PROTOCOL]	= "# Unknown protocol\n",
86 
87 	[10] = "# Input required\n",
88 	[11] = "# Input required\n",
89 	[40] = "# Temporary failure\n",
90 	[41] = "# Server unavailable\n",
91 	[42] = "# CGI error\n",
92 	[43] = "# Proxy error\n",
93 	[44] = "# Slow down\n",
94 	[50] = "# Permanent failure\n",
95 	[51] = "# Not found\n",
96 	[52] = "# Gone\n",
97 	[53] = "# Proxy request refused\n",
98 	[59] = "# Bad request\n",
99 	[60] = "# Client certificate required\n",
100 	[61] = "# Certificate not authorised\n",
101 	[62] = "# Certificate not valid\n"
102 };
103 
104 static void		 die(void) __attribute__((__noreturn__));
105 static struct tab	*tab_by_id(uint32_t);
106 static void		 handle_imsg_err(struct imsg *, size_t);
107 static void		 handle_imsg_check_cert(struct imsg *, size_t);
108 static void		 handle_check_cert_user_choice(int, struct tab *);
109 static void		 handle_maybe_save_new_cert(int, struct tab *);
110 static void		 handle_imsg_got_code(struct imsg *, size_t);
111 static void		 handle_imsg_got_meta(struct imsg *, size_t);
112 static void		 handle_maybe_save_page(int, struct tab *);
113 static void		 handle_save_page_path(const char *, struct tab *);
114 static void		 handle_imsg_file_opened(struct imsg *, size_t);
115 static void		 handle_imsg_buf(struct imsg *, size_t);
116 static void		 handle_imsg_eof(struct imsg *, size_t);
117 static void		 handle_imsg_bookmark_ok(struct imsg *, size_t);
118 static void		 handle_imsg_save_cert_ok(struct imsg *, size_t);
119 static void		 handle_imsg_update_cert_ok(struct imsg *, size_t);
120 static void		 handle_imsg_session(struct imsg *, size_t);
121 static void		 handle_dispatch_imsg(int, short, void *);
122 static int		 load_about_url(struct tab *, const char *);
123 static int		 load_file_url(struct tab *, const char *);
124 static int		 load_finger_url(struct tab *, const char *);
125 static int		 load_gemini_url(struct tab *, const char *);
126 static int		 load_gopher_url(struct tab *, const char *);
127 static int		 load_via_proxy(struct tab *, const char *,
128 			     struct proxy *);
129 static int		 make_request(struct tab *, struct get_req *, int,
130 			     const char *);
131 static int		 make_fs_request(struct tab *, int, const char *);
132 static int		 do_load_url(struct tab *, const char *, const char *);
133 static pid_t		 start_child(enum telescope_process, const char *, int);
134 
135 static struct proto {
136 	const char	*schema;
137 	const char	*port;
138 	int		 (*loadfn)(struct tab *, const char *);
139 } protos[] = {
140 	{"about",	NULL,	load_about_url},
141 	{"file",	NULL,	load_file_url},
142 	{"finger",	"79",	load_finger_url},
143 	{"gemini",	"1965",	load_gemini_url},
144 	{"gopher",	"70",	load_gopher_url},
145 	{NULL, NULL, NULL},
146 };
147 
148 static imsg_handlerfn *handlers[] = {
149 	[IMSG_ERR] = handle_imsg_err,
150 	[IMSG_CHECK_CERT] = handle_imsg_check_cert,
151 	[IMSG_GOT_CODE] = handle_imsg_got_code,
152 	[IMSG_GOT_META] = handle_imsg_got_meta,
153 	[IMSG_BUF] = handle_imsg_buf,
154 	[IMSG_EOF] = handle_imsg_eof,
155 	[IMSG_BOOKMARK_OK] = handle_imsg_bookmark_ok,
156 	[IMSG_SAVE_CERT_OK] = handle_imsg_save_cert_ok,
157 	[IMSG_UPDATE_CERT_OK] = handle_imsg_update_cert_ok,
158 	[IMSG_FILE_OPENED] = handle_imsg_file_opened,
159 	[IMSG_SESSION_TAB] = handle_imsg_session,
160 	[IMSG_SESSION_END] = handle_imsg_session,
161 };
162 
163 static struct ohash	certs;
164 
165 static void __attribute__((__noreturn__))
166 die(void)
167 {
168 	abort(); 		/* TODO */
169 }
170 
171 static struct tab *
172 tab_by_id(uint32_t id)
173 {
174 	struct tab *t;
175 
176 	TAILQ_FOREACH(t, &tabshead, tabs) {
177 		if (t->id == id)
178 			return t;
179 	}
180 
181 	return NULL;
182 }
183 
184 static void
185 handle_imsg_err(struct imsg *imsg, size_t datalen)
186 {
187 	struct tab	*tab;
188 	char		*page;
189 
190 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL)
191 		return;
192 
193 	page = imsg->data;
194 	page[datalen-1] = '\0';
195 
196 	if (asprintf(&page, "# Error loading %s\n\n> %s\n",
197 	    tab->hist_cur->h, page) == -1)
198 		die();
199 	load_page_from_str(tab, page);
200 	free(page);
201 }
202 
203 static void
204 handle_imsg_check_cert(struct imsg *imsg, size_t datalen)
205 {
206 	const char		*hash, *host, *port;
207 	int			 tofu_res;
208 	struct tofu_entry	*e;
209 	struct tab		*tab;
210 
211 	hash = imsg->data;
212 	if (hash[datalen-1] != '\0')
213 		abort();
214 
215 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL)
216 		return;
217 
218 	if (tab->proxy != NULL) {
219 		host = tab->proxy->host;
220 		port = tab->proxy->port;
221 	} else {
222 		host = tab->uri.host;
223 		port = tab->uri.port;
224 	}
225 
226 	if ((e = tofu_lookup(&certs, host, port)) == NULL) {
227 		/* TODO: an update in libressl/libretls changed
228 		 * significantly.  Find a better approach at storing
229 		 * the certs! */
230 		if (datalen > sizeof(e->hash))
231 			abort();
232 
233 		tofu_res = 1;	/* trust on first use */
234 		if ((e = calloc(1, sizeof(*e))) == NULL)
235 			abort();
236 		strlcpy(e->domain, host, sizeof(e->domain));
237 		if (*port != '\0' && strcmp(port, "1965")) {
238 			strlcat(e->domain, ":", sizeof(e->domain));
239 			strlcat(e->domain, port, sizeof(e->domain));
240 		}
241 		strlcpy(e->hash, hash, sizeof(e->hash));
242 		tofu_add(&certs, e);
243 		ui_send_fs(IMSG_SAVE_CERT, tab->id, e, sizeof(*e));
244 	} else
245 		tofu_res = !strcmp(hash, e->hash);
246 
247 	if (tofu_res) {
248 		if (e->verified == -1)
249 			tab->trust = TS_TEMP_TRUSTED;
250 		else if (e->verified == 1)
251 			tab->trust = TS_VERIFIED;
252 		else
253 			tab->trust = TS_TRUSTED;
254 
255 		ui_send_net(IMSG_CERT_STATUS, imsg->hdr.peerid,
256 		    &tofu_res, sizeof(tofu_res));
257 	} else {
258 		tab->trust = TS_UNTRUSTED;
259 		load_page_from_str(tab, "# Certificate mismatch\n");
260 		if ((tab->cert = strdup(hash)) == NULL)
261 			die();
262 		ui_yornp("Certificate mismatch.  Proceed?",
263 		    handle_check_cert_user_choice, tab);
264 	}
265 }
266 
267 static void
268 handle_check_cert_user_choice(int accept, struct tab *tab)
269 {
270 	ui_send_net(IMSG_CERT_STATUS, tab->id, &accept,
271 	    sizeof(accept));
272 
273 	if (accept) {
274 		/*
275 		 * trust the certificate for this session only.  If
276 		 * the page results in a redirect while we're asking
277 		 * the user to save, we'll end up with an invalid
278 		 * tabid (one request == one tab id).  It also makes
279 		 * sense to save it for the current session if the
280 		 * user accepted it.
281 		 */
282 		tofu_temp_trust(&certs, tab->uri.host, tab->uri.port,
283 		    tab->cert);
284 
285 		if (!safe_mode)
286 			ui_yornp("Save the new certificate?",
287 			    handle_maybe_save_new_cert, tab);
288 		else
289 			message("Certificate temporarly trusted");
290 	} else {
291 		free(tab->cert);
292 		tab->cert = NULL;
293 	}
294 }
295 
296 static void
297 handle_maybe_save_new_cert(int accept, struct tab *tab)
298 {
299 	struct tofu_entry *e;
300 	const char *host, *port;
301 
302 	if (tab->proxy != NULL) {
303 		host = tab->proxy->host;
304 		port = tab->proxy->port;
305 	} else {
306 		host = tab->uri.host;
307 		port = tab->uri.port;
308 	}
309 
310 	if (!accept)
311 		goto end;
312 
313 	if ((e = calloc(1, sizeof(*e))) == NULL)
314 		die();
315 
316 	strlcpy(e->domain, host, sizeof(e->domain));
317 	if (*port != '\0' && strcmp(port, "1965")) {
318 		strlcat(e->domain, ":", sizeof(e->domain));
319 		strlcat(e->domain, port, sizeof(e->domain));
320 	}
321 	strlcpy(e->hash, tab->cert, sizeof(e->hash));
322 	ui_send_fs(IMSG_UPDATE_CERT, 0, e, sizeof(*e));
323 
324 	tofu_update(&certs, e);
325 
326 	tab->trust = TS_TRUSTED;
327 
328 end:
329 	free(tab->cert);
330 	tab->cert = NULL;
331 }
332 
333 static inline int
334 normalize_code(int n)
335 {
336 	if (n < 20) {
337 		if (n == 10 || n == 11)
338 			return n;
339 		return 10;
340 	} else if (n < 30) {
341 		return 20;
342 	} else if (n < 40) {
343 		if (n == 30 || n == 31)
344 			return n;
345 		return 30;
346 	} else if (n < 50) {
347 		if (n <= 44)
348 			return n;
349 		return 40;
350 	} else if (n < 60) {
351 		if (n <= 53 || n == 59)
352 			return n;
353 		return 50;
354 	} else if (n < 70) {
355 		if (n <= 62)
356 			return n;
357 		return 60;
358 	} else
359 		return MALFORMED_RESPONSE;
360 }
361 
362 static void
363 handle_imsg_got_code(struct imsg *imsg, size_t datalen)
364 {
365 	struct tab	*tab;
366 
367 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL)
368 		return;
369 
370 	if (sizeof(tab->code) != datalen)
371 		die();
372 
373 	memcpy(&tab->code, imsg->data, sizeof(tab->code));
374 	tab->code = normalize_code(tab->code);
375 	if (tab->code != 30 && tab->code != 31)
376 		tab->redirect_count = 0;
377 }
378 
379 static void
380 handle_imsg_got_meta(struct imsg *imsg, size_t datalen)
381 {
382 	struct tab	*tab;
383 	char		 buf[128];
384 
385 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL)
386 		return;
387 
388 	if (sizeof(tab->meta) <= datalen)
389 		die();
390 
391 	memcpy(tab->meta, imsg->data, datalen);
392 
393 	if (tab->code < 10) {	/* internal errors */
394 		load_page_from_str(tab, err_pages[tab->code]);
395 	} else if (tab->code < 20) {	/* 1x */
396 		load_page_from_str(tab, err_pages[tab->code]);
397 		ui_require_input(tab, tab->code == 11, PROTO_GEMINI);
398 	} else if (tab->code == 20) {
399 		if (setup_parser_for(tab)) {
400 			ui_send_net(IMSG_PROCEED, tab->id, NULL, 0);
401 		} else if (safe_mode) {
402 			load_page_from_str(tab,
403 			    err_pages[UNKNOWN_TYPE_OR_CSET]);
404 		} else {
405 			struct hist *h;
406 
407 			if ((h = hist_pop(&tab->hist)) != NULL)
408 				tab->hist_cur = h;
409 			snprintf(buf, sizeof(buf),
410 			    "Can't display \"%s\", save it?", tab->meta);
411 			ui_yornp(buf, handle_maybe_save_page, tab);
412 		}
413 	} else if (tab->code < 40) { /* 3x */
414 		tab->redirect_count++;
415 
416 		/* TODO: make customizable? */
417 		if (tab->redirect_count > 5) {
418 			load_page_from_str(tab,
419 			    err_pages[TOO_MUCH_REDIRECTS]);
420 		} else
421 			do_load_url(tab, tab->meta, NULL);
422 	} else { /* 4x, 5x & 6x */
423 		load_page_from_str(tab, err_pages[tab->code]);
424 	}
425 }
426 
427 static void
428 handle_maybe_save_page(int dosave, struct tab *tab)
429 {
430 	const char	*f;
431 	char		 input[PATH_MAX];
432 
433 	/* XXX: this print a message that is confusing  */
434 	ui_on_tab_loaded(tab);
435 
436 	if (!dosave) {
437 		stop_tab(tab);
438 		return;
439 	}
440 
441 	if ((f = strrchr(tab->uri.path, '/')) == NULL)
442 		f = "";
443 	else
444 		f++;
445 
446 	strlcpy(input, download_path, sizeof(input));
447 	strlcat(input, f, sizeof(input));
448 
449 	ui_read("Save to path", handle_save_page_path, tab, input);
450 }
451 
452 static void
453 handle_save_page_path(const char *path, struct tab *tab)
454 {
455 	if (path == NULL) {
456 		stop_tab(tab);
457 		return;
458 	}
459 
460 	ui_show_downloads_pane();
461 
462 	enqueue_download(tab->id, path);
463 	ui_send_fs(IMSG_FILE_OPEN, tab->id, path, strlen(path)+1);
464 
465 	/*
466 	 * Change this tab id, the old one is associated with the
467 	 * download now.
468 	 */
469 	tab->id = tab_new_id();
470 }
471 
472 static void
473 handle_imsg_file_opened(struct imsg *imsg, size_t datalen)
474 {
475 	struct download	*d;
476 	const char	*e;
477 
478 	/*
479 	 * There are no reason we shouldn't be able to find the
480 	 * required download.
481 	 */
482 	if ((d = download_by_id(imsg->hdr.peerid)) == NULL)
483 		die();
484 
485 	if (imsg->fd == -1) {
486 		e = imsg->data;
487 		if (e[datalen-1] != '\0')
488 			die();
489 		message("Can't open file %s: %s", d->path, e);
490 	} else {
491 		d->fd = imsg->fd;
492 		ui_send_net(IMSG_PROCEED, d->id, NULL, 0);
493 	}
494 }
495 
496 static void
497 handle_imsg_session(struct imsg *imsg, size_t datalen)
498 {
499 	static struct tab	*curr;
500 	struct session_tab	 st;
501 	struct tab		*tab;
502 	int			 first_time;
503 
504 	/*
505 	 * The fs process tried to send tabs after it has announced
506 	 * that he's done.  Something fishy is going on, better die.
507 	 */
508 	if (operating)
509 		die();
510 
511 	if (imsg->hdr.type == IMSG_SESSION_END) {
512 		if (datalen != sizeof(first_time))
513 			die();
514 		memcpy(&first_time, imsg->data, sizeof(first_time));
515 		if (first_time) {
516 			new_tab("about:new", NULL, NULL);
517 			curr = new_tab("about:help", NULL, NULL);
518 		}
519 
520 		operating = 1;
521 		if (curr != NULL)
522 			switch_to_tab(curr);
523 		if (has_url || TAILQ_EMPTY(&tabshead))
524 			new_tab(url, NULL, NULL);
525 		ui_main_loop();
526 		return;
527 	}
528 
529 	if (datalen != sizeof(st))
530 		die();
531 
532 	memcpy(&st, imsg->data, sizeof(st));
533 	if ((tab = new_tab(st.uri, NULL, NULL)) == NULL)
534 		die();
535 	strlcpy(tab->buffer.page.title, st.title,
536 	    sizeof(tab->buffer.page.title));
537 	if (st.flags & TAB_CURRENT)
538 		curr = tab;
539 }
540 
541 static void
542 handle_imsg_buf(struct imsg *imsg, size_t datalen)
543 {
544 	struct tab	*tab = NULL;
545 	struct download	*d = NULL;
546 
547 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL &&
548 	    (d = download_by_id(imsg->hdr.peerid)) == NULL)
549 		return;
550 
551 	if (tab != NULL) {
552 		if (!parser_parse(tab, imsg->data, datalen))
553 			die();
554 		ui_on_tab_refresh(tab);
555 	} else {
556 		d->bytes += datalen;
557 		write(d->fd, imsg->data, datalen);
558 		ui_on_download_refresh();
559 	}
560 }
561 
562 static void
563 handle_imsg_eof(struct imsg *imsg, size_t datalen)
564 {
565 	struct tab	*tab = NULL;
566 	struct download	*d = NULL;
567 
568 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL &&
569 	    (d = download_by_id(imsg->hdr.peerid)) == NULL)
570 		return;
571 
572 	if (tab != NULL) {
573 		if (!parser_free(tab))
574 			die();
575 		ui_on_tab_refresh(tab);
576 		ui_on_tab_loaded(tab);
577 	} else {
578 		close(d->fd);
579 		d->fd = -1;
580 		ui_on_download_refresh();
581 	}
582 }
583 
584 static void
585 handle_imsg_bookmark_ok(struct imsg *imsg, size_t datalen)
586 {
587 	int res;
588 
589 	if (datalen != sizeof(res))
590 		die();
591 
592 	memcpy(&res, imsg->data, sizeof(res));
593 	if (res == 0)
594 		message("Added to bookmarks!");
595 	else
596 		message("Failed to add to bookmarks: %s",
597 		    strerror(res));
598 }
599 
600 static void
601 handle_imsg_save_cert_ok(struct imsg *imsg, size_t datalen)
602 {
603 	int res;
604 
605 	if (datalen != sizeof(res))
606 		die();
607 	memcpy(&res, imsg->data, datalen);
608 	if (res != 0)
609 		message("Failed to save the cert for: %s",
610 		    strerror(res));
611 }
612 
613 static void
614 handle_imsg_update_cert_ok(struct imsg *imsg, size_t datalen)
615 {
616 	int res;
617 
618 	if (datalen != sizeof(res))
619 		die();
620 	memcpy(&res, imsg->data, datalen);
621 	if (!res)
622 		message("Failed to update the certificate");
623 }
624 
625 static void
626 handle_dispatch_imsg(int fd, short ev, void *d)
627 {
628 	struct imsgev	*iev = d;
629 
630 	if (dispatch_imsg(iev, ev, handlers, sizeof(handlers)) == -1)
631 		err(1, "connection closed");
632 }
633 
634 static int
635 load_about_url(struct tab *tab, const char *url)
636 {
637 	tab->trust = TS_UNKNOWN;
638 	parser_init(tab, gemtext_initparser);
639 	return make_fs_request(tab, IMSG_GET, url);
640 }
641 
642 static int
643 load_file_url(struct tab *tab, const char *url)
644 {
645 	tab->trust = TS_UNKNOWN;
646 	return make_fs_request(tab, IMSG_GET_FILE, tab->uri.path);
647 }
648 
649 static int
650 load_finger_url(struct tab *tab, const char *url)
651 {
652 	struct get_req	 req;
653 	size_t		 len;
654 	char		*at;
655 
656 	memset(&req, 0, sizeof(req));
657 	strlcpy(req.port, tab->uri.port, sizeof(req.port));
658 
659 	/*
660 	 * Sometimes the finger url have the user as path component
661 	 * (e.g. finger://thelambdalab.xyz/plugd), sometimes as
662 	 * userinfo (e.g. finger://cobradile@finger.farm).
663 	 */
664 	if ((at = strchr(tab->uri.host, '@')) != NULL) {
665 		len = at - tab->uri.host;
666 		memcpy(req.req, tab->uri.host, len);
667 
668 		if (len >= sizeof(req.req))
669 			die();
670 		req.req[len] = '\0';
671 
672 		strlcpy(req.host, at+1, sizeof(req.host));
673 	} else {
674 		strlcpy(req.host, tab->uri.host, sizeof(req.host));
675 
676 		/* +1 to skip the initial `/' */
677 		strlcpy(req.req, tab->uri.path+1, sizeof(req.req));
678 	}
679 	strlcat(req.req, "\r\n", sizeof(req.req));
680 
681 	parser_init(tab, textplain_initparser);
682 	return make_request(tab, &req, PROTO_FINGER, NULL);
683 }
684 
685 static int
686 load_gemini_url(struct tab *tab, const char *url)
687 {
688 	struct get_req	 req;
689 
690 	memset(&req, 0, sizeof(req));
691 	strlcpy(req.host, tab->uri.host, sizeof(req.host));
692 	strlcpy(req.port, tab->uri.port, sizeof(req.port));
693 
694 	return make_request(tab, &req, PROTO_GEMINI, tab->hist_cur->h);
695 }
696 
697 static inline const char *
698 gopher_skip_selector(const char *path, int *ret_type)
699 {
700 	*ret_type = 0;
701 
702 	if (!strcmp(path, "/") || *path == '\0') {
703 		*ret_type = '1';
704 		return path;
705 	}
706 
707 	if (*path != '/')
708 		return path;
709 	path++;
710 
711 	switch (*ret_type = *path) {
712 	case '0':
713 	case '1':
714 	case '7':
715 		break;
716 
717 	default:
718 		*ret_type = 0;
719 		path -= 1;
720 		return path;
721 	}
722 
723 	return ++path;
724 }
725 
726 static int
727 load_gopher_url(struct tab *tab, const char *url)
728 {
729 	struct get_req	 req;
730 	int		 type;
731 	const char	*path;
732 
733 	memset(&req, 0, sizeof(req));
734 	strlcpy(req.host, tab->uri.host, sizeof(req.host));
735 	strlcpy(req.port, tab->uri.port, sizeof(req.port));
736 
737 	path = gopher_skip_selector(tab->uri.path, &type);
738 	switch (type) {
739 	case '0':
740 		parser_init(tab, textplain_initparser);
741 		break;
742 	case '1':
743 		parser_init(tab, gophermap_initparser);
744 		break;
745 	case '7':
746 		ui_require_input(tab, 0, PROTO_GOPHER);
747 		return load_page_from_str(tab, err_pages[10]);
748 	default:
749 		return load_page_from_str(tab, "Unknown gopher selector");
750 	}
751 
752 	strlcpy(req.req, path, sizeof(req.req));
753 	if (*tab->uri.query != '\0') {
754 		strlcat(req.req, "?", sizeof(req.req));
755 		strlcat(req.req, tab->uri.query, sizeof(req.req));
756 	}
757 	strlcat(req.req, "\r\n", sizeof(req.req));
758 
759 	return make_request(tab, &req, PROTO_GOPHER, NULL);
760 }
761 
762 static int
763 load_via_proxy(struct tab *tab, const char *url, struct proxy *p)
764 {
765 	struct get_req req;
766 
767 	memset(&req, 0, sizeof(req));
768 	strlcpy(req.host, p->host, sizeof(req.host));
769 	strlcpy(req.port, p->port, sizeof(req.port));
770 
771 	tab->proxy = p;
772 
773 	return make_request(tab, &req, p->proto, tab->hist_cur->h);
774 }
775 
776 static int
777 make_request(struct tab *tab, struct get_req *req, int proto, const char *r)
778 {
779 	stop_tab(tab);
780 	tab->id = tab_new_id();
781 	req->proto = proto;
782 
783 	if (r != NULL) {
784 		strlcpy(req->req, r, sizeof(req->req));
785 		strlcat(req->req, "\r\n", sizeof(req->req));
786 	}
787 
788 	ui_send_net(IMSG_GET_RAW, tab->id, req, sizeof(*req));
789 
790 	/*
791 	 * So the various load_*_url can `return make_request` and
792 	 * do_load_url is happy.
793 	 */
794 	return 1;
795 }
796 
797 static int
798 make_fs_request(struct tab *tab, int type, const char *r)
799 {
800 	stop_tab(tab);
801 	tab->id = tab_new_id();
802 
803 	ui_send_fs(type, tab->id, r, strlen(r)+1);
804 
805 	/*
806 	 * So load_{about,file}_url can `return make_fs_request` and
807 	 * do_load_url is happy.
808 	 */
809 	return 1;
810 }
811 
812 void
813 gopher_send_search_req(struct tab *tab, const char *text)
814 {
815 	struct get_req	req;
816 
817 	start_loading_anim(tab);
818 
819 	memset(&req, 0, sizeof(req));
820 	strlcpy(req.host, tab->uri.host, sizeof(req.host));
821 	strlcpy(req.port, tab->uri.port, sizeof(req.port));
822 
823 	/* +2 to skip /7 */
824 	strlcpy(req.req, tab->uri.path+2, sizeof(req.req));
825 	if (*tab->uri.query != '\0') {
826 		strlcat(req.req, "?", sizeof(req.req));
827 		strlcat(req.req, tab->uri.query, sizeof(req.req));
828 	}
829 
830 	strlcat(req.req, "\t", sizeof(req.req));
831 	strlcat(req.req, text, sizeof(req.req));
832 	strlcat(req.req, "\r\n", sizeof(req.req));
833 
834 	erase_buffer(&tab->buffer);
835 	parser_init(tab, gophermap_initparser);
836 
837 	make_request(tab, &req, PROTO_GOPHER, NULL);
838 }
839 
840 /*
841  * Effectively load the given url in the given tab.  Return 1 when
842  * loading the page asynchronously, and thus when an erase_buffer can
843  * be done right after this function return, or 0 when loading the
844  * page synchronously.
845  */
846 static int
847 do_load_url(struct tab *tab, const char *url, const char *base)
848 {
849 	struct phos_uri	 uri;
850 	struct proto	*p;
851 	struct proxy	*proxy;
852 	char		*t;
853 
854 	tab->proxy = NULL;
855 
856 	tab->trust = TS_UNKNOWN;
857 
858 	if (base == NULL)
859 		memcpy(&uri, &tab->uri, sizeof(tab->uri));
860 	else
861 		phos_parse_absolute_uri(base, &uri);
862 
863 	if (!phos_resolve_uri_from_str(&uri, url, &tab->uri)) {
864 		if (asprintf(&t, "#error loading %s\n>%s\n",
865 		    url, "Can't parse the URI") == -1)
866 			die();
867 		strlcpy(tab->hist_cur->h, url, sizeof(tab->hist_cur->h));
868 		load_page_from_str(tab, t);
869 		free(t);
870 		return 0;
871 	}
872 
873 	phos_serialize_uri(&tab->uri, tab->hist_cur->h,
874 	    sizeof(tab->hist_cur->h));
875 
876 	for (p = protos; p->schema != NULL; ++p) {
877 		if (!strcmp(tab->uri.scheme, p->schema)) {
878 			/* patch the port */
879 			if (*tab->uri.port == '\0' && p->port != NULL)
880 				strlcpy(tab->uri.port, p->port,
881 				    sizeof(tab->uri.port));
882 
883 			return p->loadfn(tab, url);
884 		}
885 	}
886 
887 	TAILQ_FOREACH(proxy, &proxies, proxies) {
888 		if (!strcmp(tab->uri.scheme, proxy->match_proto))
889 			return load_via_proxy(tab, url, proxy);
890 	}
891 
892 	return load_page_from_str(tab, err_pages[UNKNOWN_PROTOCOL]);
893 }
894 
895 /*
896  * Load url in tab.  If tab is marked as lazy, only prepare the url
897  * but don't load it.  If tab is lazy and a url was already prepared,
898  * do load it!
899  */
900 void
901 load_url(struct tab *tab, const char *url, const char *base, int nohist)
902 {
903 	int lazy;
904 
905 	lazy = tab->flags & TAB_LAZY;
906 
907 	if (lazy && tab->hist_cur != NULL) {
908 		lazy = 0;
909 		tab->flags &= ~TAB_LAZY;
910 	}
911 
912 	/* can't have both nohist and lazy at the same time. */
913 	if (nohist && lazy)
914 		nohist = 0;
915 
916 	if (!nohist && (!lazy || tab->hist_cur == NULL)) {
917 		if (tab->hist_cur != NULL)
918 			hist_clear_forward(&tab->hist,
919 			    TAILQ_NEXT(tab->hist_cur, entries));
920 
921 		if ((tab->hist_cur = calloc(1, sizeof(*tab->hist_cur)))
922 		    == NULL) {
923 			event_loopbreak();
924 			return;
925 		}
926 
927 		strlcpy(tab->buffer.page.title, url,
928 		    sizeof(tab->buffer.page.title));
929 		hist_push(&tab->hist, tab->hist_cur);
930 
931 		if (lazy)
932 			strlcpy(tab->hist_cur->h, url,
933 			    sizeof(tab->hist_cur->h));
934 	}
935 
936 	if (!lazy)
937 		do_load_url(tab, url, base);
938 }
939 
940 void
941 load_url_in_tab(struct tab *tab, const char *url, const char *base, int nohist)
942 {
943 	if (!operating) {
944 		load_url(tab, url, base, nohist);
945 		return;
946 	}
947 
948 	autosave_hook();
949 
950 	message("Loading %s...", url);
951 	start_loading_anim(tab);
952 	load_url(tab, url, base, nohist);
953 }
954 
955 int
956 load_previous_page(struct tab *tab)
957 {
958 	struct hist	*h;
959 
960 	if ((h = TAILQ_PREV(tab->hist_cur, mhisthead, entries)) == NULL)
961 		return 0;
962 	tab->hist_cur = h;
963 	do_load_url(tab, h->h, NULL);
964 	return 1;
965 }
966 
967 int
968 load_next_page(struct tab *tab)
969 {
970 	struct hist	*h;
971 
972 	if ((h = TAILQ_NEXT(tab->hist_cur, entries)) == NULL)
973 		return 0;
974 	tab->hist_cur = h;
975 	do_load_url(tab, h->h, NULL);
976 	return 1;
977 }
978 
979 void
980 add_to_bookmarks(const char *str)
981 {
982 	ui_send_fs(IMSG_BOOKMARK_PAGE, 0,
983 	    str, strlen(str)+1);
984 }
985 
986 /*
987  * Given a user-entered URL, apply some heuristics to use it:
988  *
989  * - if it's a proper url use it
990  * - if it starts with a `./' or a `/' assume its a file:// url
991  * - assume it's a gemini:// url
992  *
993  * `ret' (of which len is the size) will be filled with the resulting
994  * url.
995  */
996 void
997 humanify_url(const char *raw, char *ret, size_t len)
998 {
999 	struct phos_uri	uri;
1000 	char		buf[PATH_MAX];
1001 
1002 	if (phos_parse_absolute_uri(raw, &uri)) {
1003 		strlcpy(ret, raw, len);
1004 		return;
1005 	}
1006 
1007 	if (has_prefix(raw, "./")) {
1008 		strlcpy(ret, "file://", len);
1009 		getcwd(buf, sizeof(buf));
1010 		strlcat(ret, buf, len);
1011 		strlcat(ret, "/", len);
1012 		strlcat(ret, raw+2, len);
1013 		return;
1014 	}
1015 
1016 	if (*raw == '/') {
1017 		strlcpy(ret, "file://", len);
1018 		strlcat(ret, raw, len);
1019 		return;
1020 	}
1021 
1022 	strlcpy(ret, "gemini://", len);
1023 	strlcat(ret, raw, len);
1024 }
1025 
1026 static pid_t
1027 start_child(enum telescope_process p, const char *argv0, int fd)
1028 {
1029 	const char	*argv[5];
1030 	int		 argc = 0;
1031 	pid_t		 pid;
1032 
1033 	switch (pid = fork()) {
1034 	case -1:
1035 		die();
1036 	case 0:
1037 		break;
1038 	default:
1039 		close(fd);
1040 		return pid;
1041 	}
1042 
1043 	if (dup2(fd, 3) == -1)
1044 		err(1, "cannot setup imsg fd");
1045 
1046 	argv[argc++] = argv0;
1047 	switch (p) {
1048 	case PROC_UI:
1049 		errx(1, "Can't start ui process");
1050 	case PROC_FS:
1051 		argv[argc++] = "-Tf";
1052 		break;
1053 	case PROC_NET:
1054 		argv[argc++] = "-Tn";
1055 		break;
1056 	}
1057 
1058 	if (safe_mode)
1059 		argv[argc++] = "-S";
1060 
1061 	argv[argc++] = NULL;
1062 	execvp(argv0, (char *const *)argv);
1063 	err(1, "execvp(%s)", argv0);
1064 }
1065 
1066 int
1067 ui_send_net(int type, uint32_t peerid, const void *data,
1068     uint16_t datalen)
1069 {
1070 	return imsg_compose_event(iev_net, type, peerid, 0, -1, data,
1071 	    datalen);
1072 }
1073 
1074 int
1075 ui_send_fs(int type, uint32_t peerid, const void *data, uint16_t datalen)
1076 {
1077 	return imsg_compose_event(iev_fs, type, peerid, 0, -1, data,
1078 	    datalen);
1079 }
1080 
1081 static void __attribute__((noreturn))
1082 usage(int r)
1083 {
1084 	fprintf(stderr, "USAGE: %s [-ChnSv] [-c config] [url]\n",
1085 	    getprogname());
1086 	fprintf(stderr, "version: " PACKAGE " " VERSION "\n");
1087 	exit(r);
1088 }
1089 
1090 int
1091 main(int argc, char * const *argv)
1092 {
1093 	struct imsgev	 net_ibuf, fs_ibuf;
1094 	pid_t		 pid;
1095 	int		 pipe2net[2], pipe2fs[2];
1096 	int		 ch, configtest = 0, fail = 0;
1097 	int		 proc = -1;
1098 	int		 sessionfd = -1;
1099 	int		 status;
1100 	const char	*argv0;
1101 
1102 	argv0 = argv[0];
1103 
1104 	signal(SIGCHLD, SIG_IGN);
1105 	signal(SIGPIPE, SIG_IGN);
1106 
1107 	if (getenv("NO_COLOR") != NULL)
1108 		enable_colors = 0;
1109 
1110 	fs_init();
1111 
1112 	while ((ch = getopt_long(argc, argv, opts, longopts, NULL)) != -1) {
1113 		switch (ch) {
1114 		case 'C':
1115 			exit(ui_print_colors());
1116 		case 'c':
1117 			fail = 1;
1118 			strlcpy(config_path, optarg, sizeof(config_path));
1119 			break;
1120 		case 'n':
1121 			configtest = 1;
1122 			break;
1123 		case 'h':
1124 			usage(0);
1125 		case 'S':
1126 			safe_mode = 1;
1127 			break;
1128 		case 'T':
1129 			switch (*optarg) {
1130 			case 'f':
1131 				proc = PROC_FS;
1132 				break;
1133 			case 'n':
1134 				proc = PROC_NET;
1135 				break;
1136 			default:
1137 				errx(1, "invalid process spec %c",
1138 				    *optarg);
1139 			}
1140 			break;
1141 		case 'v':
1142 			printf("%s %s\n", PACKAGE_NAME, PACKAGE_VERSION);
1143 			exit(0);
1144 			break;
1145 		default:
1146 			usage(1);
1147 		}
1148 	}
1149 
1150 	argc -= optind;
1151 	argv += optind;
1152 
1153 	if (proc != -1) {
1154 		if (argc > 0)
1155 			usage(1);
1156 		else if (proc == PROC_FS)
1157 			return fs_main();
1158 		else if (proc == PROC_NET)
1159 			return net_main();
1160 		else
1161 			usage(1);
1162 	}
1163 
1164 	if (argc != 0) {
1165 		has_url = 1;
1166 		humanify_url(argv[0], url, sizeof(url));
1167 	}
1168 
1169 	/* setup keys before reading the config */
1170 	TAILQ_INIT(&global_map.m);
1171 	global_map.unhandled_input = global_key_unbound;
1172 	TAILQ_INIT(&minibuffer_map.m);
1173 
1174 	config_init();
1175 	parseconfig(config_path, fail);
1176 	if (configtest) {
1177 		puts("config OK");
1178 		exit(0);
1179 	}
1180 
1181 	if (download_path == NULL &&
1182 	    (download_path = strdup("/tmp/")) == NULL)
1183 		errx(1, "strdup");
1184 
1185 	if (!safe_mode && (sessionfd = lock_session()) == -1)
1186 		errx(1, "can't lock session, is another instance of "
1187 		    "telescope already running?");
1188 
1189 	/* Start children. */
1190 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pipe2fs) == -1)
1191 		err(1, "socketpair");
1192 	start_child(PROC_FS, argv0, pipe2fs[1]);
1193 	imsg_init(&fs_ibuf.ibuf, pipe2fs[0]);
1194 	iev_fs = &fs_ibuf;
1195 	iev_fs->handler = handle_dispatch_imsg;
1196 
1197 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pipe2net) == -1)
1198 		err(1, "socketpair");
1199 	start_child(PROC_NET, argv0, pipe2net[1]);
1200 	imsg_init(&net_ibuf.ibuf, pipe2net[0]);
1201 	iev_net = &net_ibuf;
1202 	iev_net->handler = handle_dispatch_imsg;
1203 
1204 	setproctitle("ui");
1205 
1206 	/* initialize tofu & load certificates */
1207 	tofu_init(&certs, 5, offsetof(struct tofu_entry, domain));
1208 	load_certs(&certs);
1209 
1210 	event_init();
1211 
1212 	/* Setup event handler for the autosave */
1213 	autosave_init();
1214 
1215 	/* Setup event handlers for pipes to fs/net */
1216 	iev_fs->events = EV_READ;
1217 	event_set(&iev_fs->ev, iev_fs->ibuf.fd, iev_fs->events,
1218 	    iev_fs->handler, iev_fs);
1219 	event_add(&iev_fs->ev, NULL);
1220 
1221 	iev_net->events = EV_READ;
1222 	event_set(&iev_net->ev, iev_net->ibuf.fd, iev_net->events,
1223 	    iev_net->handler, iev_net);
1224 	event_add(&iev_net->ev, NULL);
1225 
1226 	if (ui_init()) {
1227 		sandbox_ui_process();
1228 		event_dispatch();
1229 		ui_end();
1230 	}
1231 
1232 	ui_send_fs(IMSG_QUIT, 0, NULL, 0);
1233 	ui_send_net(IMSG_QUIT, 0, NULL, 0);
1234 	imsg_flush(&iev_fs->ibuf);
1235 	imsg_flush(&iev_net->ibuf);
1236 
1237 	/* wait for children to terminate */
1238 	do {
1239 		pid = wait(&status);
1240 		if (pid == -1) {
1241 			if (errno != EINTR && errno != ECHILD)
1242 				err(1, "wait");
1243 		} else if (WIFSIGNALED(status))
1244 			warnx("child terminated; signal %d", WTERMSIG(status));
1245 	} while (pid != -1 || (pid == -1 && errno == EINTR));
1246 
1247 	if (!safe_mode && close(sessionfd) == -1)
1248 		err(1, "close(sessionfd = %d)", sessionfd);
1249 
1250 	return 0;
1251 }