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 	{"colours",	no_argument,    NULL,   'C'},
41 	{"help",	no_argument,	NULL,	'h'},
42 	{"safe",	no_argument,	NULL,	'S'},
43 	{"version",	no_argument,	NULL,	'v'},
44 	{NULL,		0,		NULL,	0},
45 };
46 
47 static const char *opts = "Cc:hnST:v";
48 
49 static int	has_url;
50 static char	url[GEMINI_URL_LEN];
51 
52 /*
53  * Used to know when we're finished loading.
54  */
55 int			 operating;
56 
57 /*
58  * "Safe" (or "sandobox") mode.  If enabled, Telescope shouldn't write
59  * anything to the filesystem or execute external programs.
60  */
61 int			safe_mode;
62 
63 static struct imsgev	*iev_fs, *iev_net;
64 
65 struct tabshead		 tabshead = TAILQ_HEAD_INITIALIZER(tabshead);
66 struct proxylist	 proxies = TAILQ_HEAD_INITIALIZER(proxies);
67 
68 enum telescope_process {
69 	PROC_UI,
70 	PROC_FS,
71 	PROC_NET,
72 };
73 
74 #define CANNOT_FETCH		0
75 #define TOO_MUCH_REDIRECTS	1
76 #define MALFORMED_RESPONSE	2
77 #define UNKNOWN_TYPE_OR_CSET	3
78 #define UNKNOWN_PROTOCOL	4
79 
80 /* XXX: keep in sync with normalize_code */
81 const char *err_pages[70] = {
82 	[CANNOT_FETCH]		= "# Couldn't load the page\n",
83 	[TOO_MUCH_REDIRECTS]	= "# Too much redirects\n",
84 	[MALFORMED_RESPONSE]	= "# Got a malformed response\n",
85 	[UNKNOWN_TYPE_OR_CSET]	= "# Unsupported type or charset\n",
86 	[UNKNOWN_PROTOCOL]	= "# Unknown protocol\n",
87 
88 	[10] = "# Input required\n",
89 	[11] = "# Input required\n",
90 	[40] = "# Temporary failure\n",
91 	[41] = "# Server unavailable\n",
92 	[42] = "# CGI error\n",
93 	[43] = "# Proxy error\n",
94 	[44] = "# Slow down\n",
95 	[50] = "# Permanent failure\n",
96 	[51] = "# Not found\n",
97 	[52] = "# Gone\n",
98 	[53] = "# Proxy request refused\n",
99 	[59] = "# Bad request\n",
100 	[60] = "# Client certificate required\n",
101 	[61] = "# Certificate not authorised\n",
102 	[62] = "# Certificate not valid\n"
103 };
104 
105 static void		 die(void) __attribute__((__noreturn__));
106 static struct tab	*tab_by_id(uint32_t);
107 static void		 handle_imsg_err(struct imsg *, size_t);
108 static void		 handle_imsg_check_cert(struct imsg *, size_t);
109 static void		 handle_check_cert_user_choice(int, struct tab *);
110 static void		 handle_maybe_save_new_cert(int, struct tab *);
111 static void		 handle_imsg_got_code(struct imsg *, size_t);
112 static void		 handle_imsg_got_meta(struct imsg *, size_t);
113 static void		 handle_maybe_save_page(int, struct tab *);
114 static void		 handle_save_page_path(const char *, struct tab *);
115 static void		 handle_imsg_file_opened(struct imsg *, size_t);
116 static void		 handle_imsg_buf(struct imsg *, size_t);
117 static void		 handle_imsg_eof(struct imsg *, size_t);
118 static void		 handle_imsg_tofu(struct imsg *, size_t);
119 static void		 handle_imsg_bookmark_ok(struct imsg *, size_t);
120 static void		 handle_imsg_save_cert_ok(struct imsg *, size_t);
121 static void		 handle_imsg_update_cert_ok(struct imsg *, size_t);
122 static void		 handle_imsg_session(struct imsg *, size_t);
123 static void		 handle_dispatch_imsg(int, short, void *);
124 static int		 load_about_url(struct tab *, const char *);
125 static int		 load_file_url(struct tab *, const char *);
126 static int		 load_finger_url(struct tab *, const char *);
127 static int		 load_gemini_url(struct tab *, const char *);
128 static int		 load_gopher_url(struct tab *, const char *);
129 static int		 load_via_proxy(struct tab *, const char *,
130 			     struct proxy *);
131 static int		 make_request(struct tab *, struct get_req *, int,
132 			     const char *);
133 static int		 make_fs_request(struct tab *, int, const char *);
134 static int		 do_load_url(struct tab *, const char *, const char *);
135 static pid_t		 start_child(enum telescope_process, const char *, int);
136 
137 static struct proto {
138 	const char	*schema;
139 	const char	*port;
140 	int		 (*loadfn)(struct tab *, const char *);
141 } protos[] = {
142 	{"about",	NULL,	load_about_url},
143 	{"file",	NULL,	load_file_url},
144 	{"finger",	"79",	load_finger_url},
145 	{"gemini",	"1965",	load_gemini_url},
146 	{"gopher",	"70",	load_gopher_url},
147 	{NULL, NULL, NULL},
148 };
149 
150 static imsg_handlerfn *handlers[] = {
151 	[IMSG_ERR] = handle_imsg_err,
152 	[IMSG_CHECK_CERT] = handle_imsg_check_cert,
153 	[IMSG_GOT_CODE] = handle_imsg_got_code,
154 	[IMSG_GOT_META] = handle_imsg_got_meta,
155 	[IMSG_BUF] = handle_imsg_buf,
156 	[IMSG_EOF] = handle_imsg_eof,
157 	[IMSG_TOFU] = handle_imsg_tofu,
158 	[IMSG_BOOKMARK_OK] = handle_imsg_bookmark_ok,
159 	[IMSG_SAVE_CERT_OK] = handle_imsg_save_cert_ok,
160 	[IMSG_UPDATE_CERT_OK] = handle_imsg_update_cert_ok,
161 	[IMSG_FILE_OPENED] = handle_imsg_file_opened,
162 	[IMSG_SESSION_TAB] = handle_imsg_session,
163 	[IMSG_SESSION_TAB_HIST] = handle_imsg_session,
164 	[IMSG_SESSION_END] = handle_imsg_session,
165 };
166 
167 static struct ohash	certs;
168 
169 static void __attribute__((__noreturn__))
170 die(void)
171 {
172 	abort(); 		/* TODO */
173 }
174 
175 static struct tab *
176 tab_by_id(uint32_t id)
177 {
178 	struct tab *t;
179 
180 	TAILQ_FOREACH(t, &tabshead, tabs) {
181 		if (t->id == id)
182 			return t;
183 	}
184 
185 	return NULL;
186 }
187 
188 static void
189 handle_imsg_err(struct imsg *imsg, size_t datalen)
190 {
191 	struct tab	*tab;
192 	char		*page;
193 
194 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL)
195 		return;
196 
197 	page = imsg->data;
198 	page[datalen-1] = '\0';
199 
200 	if (asprintf(&page, "# Error loading %s\n\n> %s\n",
201 	    tab->hist_cur->h, page) == -1)
202 		die();
203 	load_page_from_str(tab, page);
204 	free(page);
205 }
206 
207 static void
208 handle_imsg_check_cert(struct imsg *imsg, size_t datalen)
209 {
210 	const char		*hash, *host, *port;
211 	int			 tofu_res;
212 	struct tofu_entry	*e;
213 	struct tab		*tab;
214 
215 	hash = imsg->data;
216 	if (hash[datalen-1] != '\0')
217 		abort();
218 
219 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL)
220 		return;
221 
222 	if (tab->proxy != NULL) {
223 		host = tab->proxy->host;
224 		port = tab->proxy->port;
225 	} else {
226 		host = tab->uri.host;
227 		port = tab->uri.port;
228 	}
229 
230 	if ((e = tofu_lookup(&certs, host, port)) == NULL) {
231 		/* TODO: an update in libressl/libretls changed
232 		 * significantly.  Find a better approach at storing
233 		 * the certs! */
234 		if (datalen > sizeof(e->hash))
235 			abort();
236 
237 		tofu_res = 1;	/* trust on first use */
238 		if ((e = calloc(1, sizeof(*e))) == NULL)
239 			abort();
240 		strlcpy(e->domain, host, sizeof(e->domain));
241 		if (*port != '\0' && strcmp(port, "1965")) {
242 			strlcat(e->domain, ":", sizeof(e->domain));
243 			strlcat(e->domain, port, sizeof(e->domain));
244 		}
245 		strlcpy(e->hash, hash, sizeof(e->hash));
246 		tofu_add(&certs, e);
247 		ui_send_fs(IMSG_SAVE_CERT, tab->id, e, sizeof(*e));
248 	} else
249 		tofu_res = !strcmp(hash, e->hash);
250 
251 	if (tofu_res) {
252 		if (e->verified == -1)
253 			tab->trust = TS_TEMP_TRUSTED;
254 		else if (e->verified == 1)
255 			tab->trust = TS_VERIFIED;
256 		else
257 			tab->trust = TS_TRUSTED;
258 
259 		ui_send_net(IMSG_CERT_STATUS, imsg->hdr.peerid,
260 		    &tofu_res, sizeof(tofu_res));
261 	} else {
262 		tab->trust = TS_UNTRUSTED;
263 		load_page_from_str(tab, "# Certificate mismatch\n");
264 		if ((tab->cert = strdup(hash)) == NULL)
265 			die();
266 		ui_yornp("Certificate mismatch.  Proceed?",
267 		    handle_check_cert_user_choice, tab);
268 	}
269 }
270 
271 static void
272 handle_check_cert_user_choice(int accept, struct tab *tab)
273 {
274 	ui_send_net(IMSG_CERT_STATUS, tab->id, &accept,
275 	    sizeof(accept));
276 
277 	if (accept) {
278 		/*
279 		 * trust the certificate for this session only.  If
280 		 * the page results in a redirect while we're asking
281 		 * the user to save, we'll end up with an invalid
282 		 * tabid (one request == one tab id).  It also makes
283 		 * sense to save it for the current session if the
284 		 * user accepted it.
285 		 */
286 		tofu_temp_trust(&certs, tab->uri.host, tab->uri.port,
287 		    tab->cert);
288 
289 		if (!safe_mode)
290 			ui_yornp("Save the new certificate?",
291 			    handle_maybe_save_new_cert, tab);
292 		else
293 			message("Certificate temporarly trusted");
294 	} else {
295 		free(tab->cert);
296 		tab->cert = NULL;
297 	}
298 }
299 
300 static void
301 handle_maybe_save_new_cert(int accept, struct tab *tab)
302 {
303 	struct tofu_entry *e;
304 	const char *host, *port;
305 
306 	if (tab->proxy != NULL) {
307 		host = tab->proxy->host;
308 		port = tab->proxy->port;
309 	} else {
310 		host = tab->uri.host;
311 		port = tab->uri.port;
312 	}
313 
314 	if (!accept)
315 		goto end;
316 
317 	if ((e = calloc(1, sizeof(*e))) == NULL)
318 		die();
319 
320 	strlcpy(e->domain, host, sizeof(e->domain));
321 	if (*port != '\0' && strcmp(port, "1965")) {
322 		strlcat(e->domain, ":", sizeof(e->domain));
323 		strlcat(e->domain, port, sizeof(e->domain));
324 	}
325 	strlcpy(e->hash, tab->cert, sizeof(e->hash));
326 	ui_send_fs(IMSG_UPDATE_CERT, 0, e, sizeof(*e));
327 
328 	tofu_update(&certs, e);
329 
330 	tab->trust = TS_TRUSTED;
331 
332 end:
333 	free(tab->cert);
334 	tab->cert = NULL;
335 }
336 
337 static inline int
338 normalize_code(int n)
339 {
340 	if (n < 20) {
341 		if (n == 10 || n == 11)
342 			return n;
343 		return 10;
344 	} else if (n < 30) {
345 		return 20;
346 	} else if (n < 40) {
347 		if (n == 30 || n == 31)
348 			return n;
349 		return 30;
350 	} else if (n < 50) {
351 		if (n <= 44)
352 			return n;
353 		return 40;
354 	} else if (n < 60) {
355 		if (n <= 53 || n == 59)
356 			return n;
357 		return 50;
358 	} else if (n < 70) {
359 		if (n <= 62)
360 			return n;
361 		return 60;
362 	} else
363 		return MALFORMED_RESPONSE;
364 }
365 
366 static void
367 handle_imsg_got_code(struct imsg *imsg, size_t datalen)
368 {
369 	struct tab	*tab;
370 
371 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL)
372 		return;
373 
374 	if (sizeof(tab->code) != datalen)
375 		die();
376 
377 	memcpy(&tab->code, imsg->data, sizeof(tab->code));
378 	tab->code = normalize_code(tab->code);
379 	if (tab->code != 30 && tab->code != 31)
380 		tab->redirect_count = 0;
381 }
382 
383 static void
384 handle_imsg_got_meta(struct imsg *imsg, size_t datalen)
385 {
386 	struct tab	*tab;
387 	char		 buf[128];
388 
389 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL)
390 		return;
391 
392 	if (sizeof(tab->meta) <= datalen)
393 		die();
394 
395 	memcpy(tab->meta, imsg->data, datalen);
396 
397 	if (tab->code < 10) {	/* internal errors */
398 		load_page_from_str(tab, err_pages[tab->code]);
399 	} else if (tab->code < 20) {	/* 1x */
400 		load_page_from_str(tab, err_pages[tab->code]);
401 		ui_require_input(tab, tab->code == 11, PROTO_GEMINI);
402 	} else if (tab->code == 20) {
403 		if (setup_parser_for(tab)) {
404 			ui_send_net(IMSG_PROCEED, tab->id, NULL, 0);
405 		} else if (safe_mode) {
406 			load_page_from_str(tab,
407 			    err_pages[UNKNOWN_TYPE_OR_CSET]);
408 		} else {
409 			struct hist *h;
410 
411 			if ((h = hist_pop(&tab->hist)) != NULL)
412 				tab->hist_cur = h;
413 			snprintf(buf, sizeof(buf),
414 			    "Can't display \"%s\", save it?", tab->meta);
415 			ui_yornp(buf, handle_maybe_save_page, tab);
416 		}
417 	} else if (tab->code < 40) { /* 3x */
418 		tab->redirect_count++;
419 
420 		/* TODO: make customizable? */
421 		if (tab->redirect_count > 5) {
422 			load_page_from_str(tab,
423 			    err_pages[TOO_MUCH_REDIRECTS]);
424 		} else
425 			do_load_url(tab, tab->meta, NULL);
426 	} else { /* 4x, 5x & 6x */
427 		load_page_from_str(tab, err_pages[tab->code]);
428 	}
429 }
430 
431 static void
432 handle_maybe_save_page(int dosave, struct tab *tab)
433 {
434 	const char	*f;
435 	char		 input[PATH_MAX];
436 
437 	/* XXX: this print a message that is confusing  */
438 	ui_on_tab_loaded(tab);
439 
440 	if (!dosave) {
441 		stop_tab(tab);
442 		return;
443 	}
444 
445 	if ((f = strrchr(tab->uri.path, '/')) == NULL)
446 		f = "";
447 	else
448 		f++;
449 
450 	strlcpy(input, download_path, sizeof(input));
451 	strlcat(input, f, sizeof(input));
452 
453 	ui_read("Save to path", handle_save_page_path, tab, input);
454 }
455 
456 static void
457 handle_save_page_path(const char *path, struct tab *tab)
458 {
459 	if (path == NULL) {
460 		stop_tab(tab);
461 		return;
462 	}
463 
464 	ui_show_downloads_pane();
465 
466 	enqueue_download(tab->id, path);
467 	ui_send_fs(IMSG_FILE_OPEN, tab->id, path, strlen(path)+1);
468 
469 	/*
470 	 * Change this tab id, the old one is associated with the
471 	 * download now.
472 	 */
473 	tab->id = tab_new_id();
474 }
475 
476 static void
477 handle_imsg_file_opened(struct imsg *imsg, size_t datalen)
478 {
479 	struct download	*d;
480 	const char	*e;
481 
482 	/*
483 	 * There are no reason we shouldn't be able to find the
484 	 * required download.
485 	 */
486 	if ((d = download_by_id(imsg->hdr.peerid)) == NULL)
487 		die();
488 
489 	if (imsg->fd == -1) {
490 		e = imsg->data;
491 		if (e[datalen-1] != '\0')
492 			die();
493 		message("Can't open file %s: %s", d->path, e);
494 	} else {
495 		d->fd = imsg->fd;
496 		ui_send_net(IMSG_PROCEED, d->id, NULL, 0);
497 	}
498 }
499 
500 static void
501 handle_imsg_session(struct imsg *imsg, size_t datalen)
502 {
503 	static struct tab	*curr;
504 	static struct tab	*tab;
505 	struct session_tab	 st;
506 	struct session_tab_hist	 sth;
507 	struct hist		*h;
508 	int			 first_time;
509 
510 	/*
511 	 * The fs process tried to send tabs after it has announced
512 	 * that he's done.  Something fishy is going on, better die.
513 	 */
514 	if (operating)
515 		die();
516 
517 	switch (imsg->hdr.type) {
518 	case IMSG_SESSION_TAB:
519 		if (datalen != sizeof(st))
520 			die();
521 
522 		memcpy(&st, imsg->data, sizeof(st));
523 		if ((tab = new_tab(st.uri, NULL, NULL)) == NULL)
524 			die();
525 		strlcpy(tab->buffer.page.title, st.title,
526 		    sizeof(tab->buffer.page.title));
527 		if (st.flags & TAB_CURRENT)
528 			curr = tab;
529 		break;
530 
531 	case IMSG_SESSION_TAB_HIST:
532 		if (tab == NULL || datalen != sizeof(sth))
533 			die();
534 
535 		memcpy(&sth, imsg->data, sizeof(sth));
536 		if (sth.uri[sizeof(sth.uri)-1] != '\0')
537 			die();
538 
539 		if ((h = calloc(1, sizeof(*h))) == NULL)
540 			die();
541 		strlcpy(h->h, sth.uri, sizeof(h->h));
542 
543 		if (sth.future)
544 			hist_push(&tab->hist, h);
545 		else
546 			hist_add_before(&tab->hist, tab->hist_cur, h);
547 		break;
548 
549 	case IMSG_SESSION_END:
550 		if (datalen != sizeof(first_time))
551 			die();
552 		memcpy(&first_time, imsg->data, sizeof(first_time));
553 		if (first_time) {
554 			new_tab("about:new", NULL, NULL);
555 			curr = new_tab("about:help", NULL, NULL);
556 		}
557 
558 		operating = 1;
559 		if (curr != NULL)
560 			switch_to_tab(curr);
561 		if (has_url || TAILQ_EMPTY(&tabshead))
562 			new_tab(url, NULL, NULL);
563 		ui_main_loop();
564 		break;
565 
566 	default:
567 		die();
568 	}
569 }
570 
571 static void
572 handle_imsg_buf(struct imsg *imsg, size_t datalen)
573 {
574 	struct tab	*tab = NULL;
575 	struct download	*d = NULL;
576 
577 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL &&
578 	    (d = download_by_id(imsg->hdr.peerid)) == NULL)
579 		return;
580 
581 	if (tab != NULL) {
582 		if (!parser_parse(tab, imsg->data, datalen))
583 			die();
584 		ui_on_tab_refresh(tab);
585 	} else {
586 		d->bytes += datalen;
587 		write(d->fd, imsg->data, datalen);
588 		ui_on_download_refresh();
589 	}
590 }
591 
592 static void
593 handle_imsg_eof(struct imsg *imsg, size_t datalen)
594 {
595 	struct tab	*tab = NULL;
596 	struct download	*d = NULL;
597 
598 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL &&
599 	    (d = download_by_id(imsg->hdr.peerid)) == NULL)
600 		return;
601 
602 	if (tab != NULL) {
603 		if (!parser_free(tab))
604 			die();
605 		ui_on_tab_refresh(tab);
606 		ui_on_tab_loaded(tab);
607 	} else {
608 		close(d->fd);
609 		d->fd = -1;
610 		ui_on_download_refresh();
611 	}
612 }
613 
614 static void
615 handle_imsg_tofu(struct imsg *imsg, size_t datalen)
616 {
617 	struct tofu_entry *e;
618 
619 	if (operating)
620 		die();
621 
622 	if ((e = calloc(1, sizeof(*e))) == NULL)
623 		die();
624 
625 	if (datalen != sizeof(*e))
626 		die();
627 	memcpy(e, imsg->data, sizeof(*e));
628 	if (e->domain[sizeof(e->domain)-1] != '\0' ||
629 	    e->hash[sizeof(e->hash)-1] != '\0')
630 		die();
631 	tofu_add(&certs, e);
632 }
633 
634 static void
635 handle_imsg_bookmark_ok(struct imsg *imsg, size_t datalen)
636 {
637 	int res;
638 
639 	if (datalen != sizeof(res))
640 		die();
641 
642 	memcpy(&res, imsg->data, sizeof(res));
643 	if (res == 0)
644 		message("Added to bookmarks!");
645 	else
646 		message("Failed to add to bookmarks: %s",
647 		    strerror(res));
648 }
649 
650 static void
651 handle_imsg_save_cert_ok(struct imsg *imsg, size_t datalen)
652 {
653 	int res;
654 
655 	if (datalen != sizeof(res))
656 		die();
657 	memcpy(&res, imsg->data, datalen);
658 	if (res != 0)
659 		message("Failed to save the cert for: %s",
660 		    strerror(res));
661 }
662 
663 static void
664 handle_imsg_update_cert_ok(struct imsg *imsg, size_t datalen)
665 {
666 	int res;
667 
668 	if (datalen != sizeof(res))
669 		die();
670 	memcpy(&res, imsg->data, datalen);
671 	if (!res)
672 		message("Failed to update the certificate");
673 }
674 
675 static void
676 handle_dispatch_imsg(int fd, short ev, void *d)
677 {
678 	struct imsgev	*iev = d;
679 
680 	if (dispatch_imsg(iev, ev, handlers, sizeof(handlers)) == -1)
681 		err(1, "connection closed");
682 }
683 
684 static int
685 load_about_url(struct tab *tab, const char *url)
686 {
687 	tab->trust = TS_UNKNOWN;
688 	parser_init(tab, gemtext_initparser);
689 	return make_fs_request(tab, IMSG_GET, url);
690 }
691 
692 static int
693 load_file_url(struct tab *tab, const char *url)
694 {
695 	tab->trust = TS_UNKNOWN;
696 	return make_fs_request(tab, IMSG_GET_FILE, tab->uri.path);
697 }
698 
699 static int
700 load_finger_url(struct tab *tab, const char *url)
701 {
702 	struct get_req	 req;
703 	size_t		 len;
704 	char		*at;
705 
706 	memset(&req, 0, sizeof(req));
707 	strlcpy(req.port, tab->uri.port, sizeof(req.port));
708 
709 	/*
710 	 * Sometimes the finger url have the user as path component
711 	 * (e.g. finger://thelambdalab.xyz/plugd), sometimes as
712 	 * userinfo (e.g. finger://cobradile@finger.farm).
713 	 */
714 	if ((at = strchr(tab->uri.host, '@')) != NULL) {
715 		len = at - tab->uri.host;
716 		memcpy(req.req, tab->uri.host, len);
717 
718 		if (len >= sizeof(req.req))
719 			die();
720 		req.req[len] = '\0';
721 
722 		strlcpy(req.host, at+1, sizeof(req.host));
723 	} else {
724 		strlcpy(req.host, tab->uri.host, sizeof(req.host));
725 
726 		/* +1 to skip the initial `/' */
727 		strlcpy(req.req, tab->uri.path+1, sizeof(req.req));
728 	}
729 	strlcat(req.req, "\r\n", sizeof(req.req));
730 
731 	parser_init(tab, textplain_initparser);
732 	return make_request(tab, &req, PROTO_FINGER, NULL);
733 }
734 
735 static int
736 load_gemini_url(struct tab *tab, const char *url)
737 {
738 	struct get_req	 req;
739 
740 	memset(&req, 0, sizeof(req));
741 	strlcpy(req.host, tab->uri.host, sizeof(req.host));
742 	strlcpy(req.port, tab->uri.port, sizeof(req.port));
743 
744 	return make_request(tab, &req, PROTO_GEMINI, tab->hist_cur->h);
745 }
746 
747 static inline const char *
748 gopher_skip_selector(const char *path, int *ret_type)
749 {
750 	*ret_type = 0;
751 
752 	if (!strcmp(path, "/") || *path == '\0') {
753 		*ret_type = '1';
754 		return path;
755 	}
756 
757 	if (*path != '/')
758 		return path;
759 	path++;
760 
761 	switch (*ret_type = *path) {
762 	case '0':
763 	case '1':
764 	case '7':
765 		break;
766 
767 	default:
768 		*ret_type = 0;
769 		path -= 1;
770 		return path;
771 	}
772 
773 	return ++path;
774 }
775 
776 static int
777 load_gopher_url(struct tab *tab, const char *url)
778 {
779 	struct get_req	 req;
780 	int		 type;
781 	const char	*path;
782 
783 	memset(&req, 0, sizeof(req));
784 	strlcpy(req.host, tab->uri.host, sizeof(req.host));
785 	strlcpy(req.port, tab->uri.port, sizeof(req.port));
786 
787 	path = gopher_skip_selector(tab->uri.path, &type);
788 	switch (type) {
789 	case '0':
790 		parser_init(tab, textplain_initparser);
791 		break;
792 	case '1':
793 		parser_init(tab, gophermap_initparser);
794 		break;
795 	case '7':
796 		ui_require_input(tab, 0, PROTO_GOPHER);
797 		return load_page_from_str(tab, err_pages[10]);
798 	default:
799 		return load_page_from_str(tab, "Unknown gopher selector");
800 	}
801 
802 	strlcpy(req.req, path, sizeof(req.req));
803 	if (*tab->uri.query != '\0') {
804 		strlcat(req.req, "?", sizeof(req.req));
805 		strlcat(req.req, tab->uri.query, sizeof(req.req));
806 	}
807 	strlcat(req.req, "\r\n", sizeof(req.req));
808 
809 	return make_request(tab, &req, PROTO_GOPHER, NULL);
810 }
811 
812 static int
813 load_via_proxy(struct tab *tab, const char *url, struct proxy *p)
814 {
815 	struct get_req req;
816 
817 	memset(&req, 0, sizeof(req));
818 	strlcpy(req.host, p->host, sizeof(req.host));
819 	strlcpy(req.port, p->port, sizeof(req.port));
820 
821 	tab->proxy = p;
822 
823 	return make_request(tab, &req, p->proto, tab->hist_cur->h);
824 }
825 
826 static int
827 make_request(struct tab *tab, struct get_req *req, int proto, const char *r)
828 {
829 	stop_tab(tab);
830 	tab->id = tab_new_id();
831 	req->proto = proto;
832 
833 	if (r != NULL) {
834 		strlcpy(req->req, r, sizeof(req->req));
835 		strlcat(req->req, "\r\n", sizeof(req->req));
836 	}
837 
838 	ui_send_net(IMSG_GET_RAW, tab->id, req, sizeof(*req));
839 
840 	/*
841 	 * So the various load_*_url can `return make_request` and
842 	 * do_load_url is happy.
843 	 */
844 	return 1;
845 }
846 
847 static int
848 make_fs_request(struct tab *tab, int type, const char *r)
849 {
850 	stop_tab(tab);
851 	tab->id = tab_new_id();
852 
853 	ui_send_fs(type, tab->id, r, strlen(r)+1);
854 
855 	/*
856 	 * So load_{about,file}_url can `return make_fs_request` and
857 	 * do_load_url is happy.
858 	 */
859 	return 1;
860 }
861 
862 void
863 gopher_send_search_req(struct tab *tab, const char *text)
864 {
865 	struct get_req	req;
866 
867 	start_loading_anim(tab);
868 
869 	memset(&req, 0, sizeof(req));
870 	strlcpy(req.host, tab->uri.host, sizeof(req.host));
871 	strlcpy(req.port, tab->uri.port, sizeof(req.port));
872 
873 	/* +2 to skip /7 */
874 	strlcpy(req.req, tab->uri.path+2, sizeof(req.req));
875 	if (*tab->uri.query != '\0') {
876 		strlcat(req.req, "?", sizeof(req.req));
877 		strlcat(req.req, tab->uri.query, sizeof(req.req));
878 	}
879 
880 	strlcat(req.req, "\t", sizeof(req.req));
881 	strlcat(req.req, text, sizeof(req.req));
882 	strlcat(req.req, "\r\n", sizeof(req.req));
883 
884 	erase_buffer(&tab->buffer);
885 	parser_init(tab, gophermap_initparser);
886 
887 	make_request(tab, &req, PROTO_GOPHER, NULL);
888 }
889 
890 /*
891  * Effectively load the given url in the given tab.  Return 1 when
892  * loading the page asynchronously, and thus when an erase_buffer can
893  * be done right after this function return, or 0 when loading the
894  * page synchronously.
895  */
896 static int
897 do_load_url(struct tab *tab, const char *url, const char *base)
898 {
899 	struct phos_uri	 uri;
900 	struct proto	*p;
901 	struct proxy	*proxy;
902 	char		*t;
903 
904 	tab->proxy = NULL;
905 
906 	tab->trust = TS_UNKNOWN;
907 
908 	if (base == NULL)
909 		memcpy(&uri, &tab->uri, sizeof(tab->uri));
910 	else
911 		phos_parse_absolute_uri(base, &uri);
912 
913 	if (!phos_resolve_uri_from_str(&uri, url, &tab->uri)) {
914 		if (asprintf(&t, "#error loading %s\n>%s\n",
915 		    url, "Can't parse the URI") == -1)
916 			die();
917 		strlcpy(tab->hist_cur->h, url, sizeof(tab->hist_cur->h));
918 		load_page_from_str(tab, t);
919 		free(t);
920 		return 0;
921 	}
922 
923 	phos_serialize_uri(&tab->uri, tab->hist_cur->h,
924 	    sizeof(tab->hist_cur->h));
925 
926 	for (p = protos; p->schema != NULL; ++p) {
927 		if (!strcmp(tab->uri.scheme, p->schema)) {
928 			/* patch the port */
929 			if (*tab->uri.port == '\0' && p->port != NULL)
930 				strlcpy(tab->uri.port, p->port,
931 				    sizeof(tab->uri.port));
932 
933 			return p->loadfn(tab, url);
934 		}
935 	}
936 
937 	TAILQ_FOREACH(proxy, &proxies, proxies) {
938 		if (!strcmp(tab->uri.scheme, proxy->match_proto))
939 			return load_via_proxy(tab, url, proxy);
940 	}
941 
942 	return load_page_from_str(tab, err_pages[UNKNOWN_PROTOCOL]);
943 }
944 
945 /*
946  * Load url in tab and handle history.  If a tab is marked as lazy, only
947  * prepare the url but don't load it.
948  */
949 void
950 load_url(struct tab *tab, const char *url, const char *base, int nohist)
951 {
952 	int lazy = tab->flags & TAB_LAZY;
953 
954 	if (!nohist && (!lazy || tab->hist_cur == NULL)) {
955 		if (tab->hist_cur != NULL)
956 			hist_clear_forward(&tab->hist,
957 			    TAILQ_NEXT(tab->hist_cur, entries));
958 
959 		if ((tab->hist_cur = calloc(1, sizeof(*tab->hist_cur)))
960 		    == NULL) {
961 			event_loopbreak();
962 			return;
963 		}
964 
965 		strlcpy(tab->buffer.page.title, url,
966 		    sizeof(tab->buffer.page.title));
967 		hist_push(&tab->hist, tab->hist_cur);
968 
969 		if (lazy)
970 			strlcpy(tab->hist_cur->h, url,
971 			    sizeof(tab->hist_cur->h));
972 	}
973 
974 	if (!lazy)
975 		do_load_url(tab, url, base);
976 }
977 
978 void
979 load_url_in_tab(struct tab *tab, const char *url, const char *base, int nohist)
980 {
981 	if (!operating) {
982 		load_url(tab, url, base, nohist);
983 		return;
984 	}
985 
986 	autosave_hook();
987 
988 	message("Loading %s...", url);
989 	start_loading_anim(tab);
990 	load_url(tab, url, base, nohist);
991 }
992 
993 int
994 load_previous_page(struct tab *tab)
995 {
996 	struct hist	*h;
997 
998 	if ((h = TAILQ_PREV(tab->hist_cur, mhisthead, entries)) == NULL)
999 		return 0;
1000 	tab->hist_cur = h;
1001 	do_load_url(tab, h->h, NULL);
1002 	return 1;
1003 }
1004 
1005 int
1006 load_next_page(struct tab *tab)
1007 {
1008 	struct hist	*h;
1009 
1010 	if ((h = TAILQ_NEXT(tab->hist_cur, entries)) == NULL)
1011 		return 0;
1012 	tab->hist_cur = h;
1013 	do_load_url(tab, h->h, NULL);
1014 	return 1;
1015 }
1016 
1017 void
1018 add_to_bookmarks(const char *str)
1019 {
1020 	ui_send_fs(IMSG_BOOKMARK_PAGE, 0,
1021 	    str, strlen(str)+1);
1022 }
1023 
1024 /*
1025  * Given a user-entered URL, apply some heuristics to use it:
1026  *
1027  * - if it's a proper url use it
1028  * - if it starts with a `./' or a `/' assume its a file:// url
1029  * - assume it's a gemini:// url
1030  *
1031  * `ret' (of which len is the size) will be filled with the resulting
1032  * url.
1033  */
1034 void
1035 humanify_url(const char *raw, char *ret, size_t len)
1036 {
1037 	struct phos_uri	uri;
1038 	char		buf[PATH_MAX];
1039 
1040 	if (phos_parse_absolute_uri(raw, &uri)) {
1041 		strlcpy(ret, raw, len);
1042 		return;
1043 	}
1044 
1045 	if (has_prefix(raw, "./")) {
1046 		strlcpy(ret, "file://", len);
1047 		getcwd(buf, sizeof(buf));
1048 		strlcat(ret, buf, len);
1049 		strlcat(ret, "/", len);
1050 		strlcat(ret, raw+2, len);
1051 		return;
1052 	}
1053 
1054 	if (*raw == '/') {
1055 		strlcpy(ret, "file://", len);
1056 		strlcat(ret, raw, len);
1057 		return;
1058 	}
1059 
1060 	strlcpy(ret, "gemini://", len);
1061 	strlcat(ret, raw, len);
1062 }
1063 
1064 static pid_t
1065 start_child(enum telescope_process p, const char *argv0, int fd)
1066 {
1067 	const char	*argv[5];
1068 	int		 argc = 0;
1069 	pid_t		 pid;
1070 
1071 	switch (pid = fork()) {
1072 	case -1:
1073 		die();
1074 	case 0:
1075 		break;
1076 	default:
1077 		close(fd);
1078 		return pid;
1079 	}
1080 
1081 	if (dup2(fd, 3) == -1)
1082 		err(1, "cannot setup imsg fd");
1083 
1084 	argv[argc++] = argv0;
1085 	switch (p) {
1086 	case PROC_UI:
1087 		errx(1, "Can't start ui process");
1088 	case PROC_FS:
1089 		argv[argc++] = "-Tf";
1090 		break;
1091 	case PROC_NET:
1092 		argv[argc++] = "-Tn";
1093 		break;
1094 	}
1095 
1096 	if (safe_mode)
1097 		argv[argc++] = "-S";
1098 
1099 	argv[argc++] = NULL;
1100 	execvp(argv0, (char *const *)argv);
1101 	err(1, "execvp(%s)", argv0);
1102 }
1103 
1104 int
1105 ui_send_net(int type, uint32_t peerid, const void *data,
1106     uint16_t datalen)
1107 {
1108 	return imsg_compose_event(iev_net, type, peerid, 0, -1, data,
1109 	    datalen);
1110 }
1111 
1112 int
1113 ui_send_fs(int type, uint32_t peerid, const void *data, uint16_t datalen)
1114 {
1115 	return imsg_compose_event(iev_fs, type, peerid, 0, -1, data,
1116 	    datalen);
1117 }
1118 
1119 static void __attribute__((noreturn))
1120 usage(int r)
1121 {
1122 	fprintf(stderr, "USAGE: %s [-ChnSv] [-c config] [url]\n",
1123 	    getprogname());
1124 	fprintf(stderr, "version: " PACKAGE " " VERSION "\n");
1125 	exit(r);
1126 }
1127 
1128 int
1129 main(int argc, char * const *argv)
1130 {
1131 	struct imsgev	 net_ibuf, fs_ibuf;
1132 	pid_t		 pid;
1133 	int		 pipe2net[2], pipe2fs[2];
1134 	int		 ch, configtest = 0, fail = 0;
1135 	int		 proc = -1;
1136 	int		 sessionfd = -1;
1137 	int		 status;
1138 	const char	*argv0;
1139 
1140 	argv0 = argv[0];
1141 
1142 	signal(SIGCHLD, SIG_IGN);
1143 	signal(SIGPIPE, SIG_IGN);
1144 
1145 	if (getenv("NO_COLOR") != NULL)
1146 		enable_colors = 0;
1147 
1148 	fs_init();
1149 
1150 	while ((ch = getopt_long(argc, argv, opts, longopts, NULL)) != -1) {
1151 		switch (ch) {
1152 		case 'C':
1153 			exit(ui_print_colors());
1154 		case 'c':
1155 			fail = 1;
1156 			strlcpy(config_path, optarg, sizeof(config_path));
1157 			break;
1158 		case 'n':
1159 			configtest = 1;
1160 			break;
1161 		case 'h':
1162 			usage(0);
1163 		case 'S':
1164 			safe_mode = 1;
1165 			break;
1166 		case 'T':
1167 			switch (*optarg) {
1168 			case 'f':
1169 				proc = PROC_FS;
1170 				break;
1171 			case 'n':
1172 				proc = PROC_NET;
1173 				break;
1174 			default:
1175 				errx(1, "invalid process spec %c",
1176 				    *optarg);
1177 			}
1178 			break;
1179 		case 'v':
1180 			printf("%s %s\n", PACKAGE_NAME, PACKAGE_VERSION);
1181 			exit(0);
1182 			break;
1183 		default:
1184 			usage(1);
1185 		}
1186 	}
1187 
1188 	argc -= optind;
1189 	argv += optind;
1190 
1191 	if (proc != -1) {
1192 		if (argc > 0)
1193 			usage(1);
1194 		else if (proc == PROC_FS)
1195 			return fs_main();
1196 		else if (proc == PROC_NET)
1197 			return net_main();
1198 		else
1199 			usage(1);
1200 	}
1201 
1202 	if (argc != 0) {
1203 		has_url = 1;
1204 		humanify_url(argv[0], url, sizeof(url));
1205 	}
1206 
1207 	/* setup keys before reading the config */
1208 	TAILQ_INIT(&global_map.m);
1209 	global_map.unhandled_input = global_key_unbound;
1210 	TAILQ_INIT(&minibuffer_map.m);
1211 
1212 	config_init();
1213 	parseconfig(config_path, fail);
1214 	if (configtest) {
1215 		puts("config OK");
1216 		exit(0);
1217 	}
1218 
1219 	if (download_path == NULL &&
1220 	    (download_path = strdup("/tmp/")) == NULL)
1221 		errx(1, "strdup");
1222 
1223 	if (!safe_mode && (sessionfd = lock_session()) == -1)
1224 		errx(1, "can't lock session, is another instance of "
1225 		    "telescope already running?");
1226 
1227 	/* Start children. */
1228 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pipe2fs) == -1)
1229 		err(1, "socketpair");
1230 	start_child(PROC_FS, argv0, pipe2fs[1]);
1231 	imsg_init(&fs_ibuf.ibuf, pipe2fs[0]);
1232 	iev_fs = &fs_ibuf;
1233 	iev_fs->handler = handle_dispatch_imsg;
1234 
1235 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pipe2net) == -1)
1236 		err(1, "socketpair");
1237 	start_child(PROC_NET, argv0, pipe2net[1]);
1238 	imsg_init(&net_ibuf.ibuf, pipe2net[0]);
1239 	iev_net = &net_ibuf;
1240 	iev_net->handler = handle_dispatch_imsg;
1241 
1242 	setproctitle("ui");
1243 
1244 	/* initialize tofu store */
1245 	tofu_init(&certs, 5, offsetof(struct tofu_entry, domain));
1246 
1247 	event_init();
1248 
1249 	/* Setup event handler for the autosave */
1250 	autosave_init();
1251 
1252 	/* Setup event handlers for pipes to fs/net */
1253 	iev_fs->events = EV_READ;
1254 	event_set(&iev_fs->ev, iev_fs->ibuf.fd, iev_fs->events,
1255 	    iev_fs->handler, iev_fs);
1256 	event_add(&iev_fs->ev, NULL);
1257 
1258 	iev_net->events = EV_READ;
1259 	event_set(&iev_net->ev, iev_net->ibuf.fd, iev_net->events,
1260 	    iev_net->handler, iev_net);
1261 	event_add(&iev_net->ev, NULL);
1262 
1263 	if (ui_init()) {
1264 		sandbox_ui_process();
1265 		ui_send_fs(IMSG_INIT, 0, NULL, 0);
1266 		event_dispatch();
1267 		ui_end();
1268 	}
1269 
1270 	ui_send_fs(IMSG_QUIT, 0, NULL, 0);
1271 	ui_send_net(IMSG_QUIT, 0, NULL, 0);
1272 	imsg_flush(&iev_fs->ibuf);
1273 	imsg_flush(&iev_net->ibuf);
1274 
1275 	/* wait for children to terminate */
1276 	do {
1277 		pid = wait(&status);
1278 		if (pid == -1) {
1279 			if (errno != EINTR && errno != ECHILD)
1280 				err(1, "wait");
1281 		} else if (WIFSIGNALED(status))
1282 			warnx("child terminated; signal %d", WTERMSIG(status));
1283 	} while (pid != -1 || (pid == -1 && errno == EINTR));
1284 
1285 	if (!safe_mode && close(sessionfd) == -1)
1286 		err(1, "close(sessionfd = %d)", sessionfd);
1287 
1288 	return 0;
1289 }