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 "mcache.h"
33 #include "minibuffer.h"
34 #include "parser.h"
35 #include "session.h"
36 #include "telescope.h"
37 #include "ui.h"
38 #include "utils.h"
39 
40 static struct option longopts[] = {
41 	{"colors",      no_argument,    NULL,   'C'},
42 	{"colours",	no_argument,    NULL,   'C'},
43 	{"help",	no_argument,	NULL,	'h'},
44 	{"safe",	no_argument,	NULL,	'S'},
45 	{"version",	no_argument,	NULL,	'v'},
46 	{NULL,		0,		NULL,	0},
47 };
48 
49 static const char *opts = "Cc:hnST:v";
50 
51 static int	has_url;
52 static char	url[GEMINI_URL_LEN];
53 
54 /*
55  * Used to know when we're finished loading.
56  */
57 int			 operating;
58 
59 /*
60  * "Safe" (or "sandobox") mode.  If enabled, Telescope shouldn't write
61  * anything to the filesystem or execute external programs.
62  */
63 int			safe_mode;
64 
65 static struct imsgev	*iev_fs, *iev_net;
66 
67 struct tabshead		 tabshead = TAILQ_HEAD_INITIALIZER(tabshead);
68 struct tabshead		 ktabshead = TAILQ_HEAD_INITIALIZER(ktabshead);
69 struct proxylist	 proxies = TAILQ_HEAD_INITIALIZER(proxies);
70 
71 enum telescope_process {
72 	PROC_UI,
73 	PROC_FS,
74 	PROC_NET,
75 };
76 
77 #define CANNOT_FETCH		0
78 #define TOO_MUCH_REDIRECTS	1
79 #define MALFORMED_RESPONSE	2
80 #define UNKNOWN_TYPE_OR_CSET	3
81 #define UNKNOWN_PROTOCOL	4
82 
83 /* XXX: keep in sync with normalize_code */
84 const char *err_pages[70] = {
85 	[CANNOT_FETCH]		= "# Couldn't load the page\n",
86 	[TOO_MUCH_REDIRECTS]	= "# Too much redirects\n",
87 	[MALFORMED_RESPONSE]	= "# Got a malformed response\n",
88 	[UNKNOWN_TYPE_OR_CSET]	= "# Unsupported type or charset\n",
89 	[UNKNOWN_PROTOCOL]	= "# Unknown protocol\n",
90 
91 	[10] = "# Input required\n",
92 	[11] = "# Input required\n",
93 	[40] = "# Temporary failure\n",
94 	[41] = "# Server unavailable\n",
95 	[42] = "# CGI error\n",
96 	[43] = "# Proxy error\n",
97 	[44] = "# Slow down\n",
98 	[50] = "# Permanent failure\n",
99 	[51] = "# Not found\n",
100 	[52] = "# Gone\n",
101 	[53] = "# Proxy request refused\n",
102 	[59] = "# Bad request\n",
103 	[60] = "# Client certificate required\n",
104 	[61] = "# Certificate not authorised\n",
105 	[62] = "# Certificate not valid\n"
106 };
107 
108 static void		 die(void) __attribute__((__noreturn__));
109 static struct tab	*tab_by_id(uint32_t);
110 static void		 handle_imsg_err(struct imsg *, size_t);
111 static void		 handle_imsg_check_cert(struct imsg *, size_t);
112 static void		 handle_check_cert_user_choice(int, struct tab *);
113 static void		 handle_maybe_save_new_cert(int, struct tab *);
114 static void		 handle_imsg_got_code(struct imsg *, size_t);
115 static void		 handle_imsg_got_meta(struct imsg *, size_t);
116 static void		 handle_maybe_save_page(int, struct tab *);
117 static void		 handle_save_page_path(const char *, struct tab *);
118 static void		 handle_imsg_file_opened(struct imsg *, size_t);
119 static void		 handle_imsg_buf(struct imsg *, size_t);
120 static void		 handle_imsg_eof(struct imsg *, size_t);
121 static void		 handle_imsg_tofu(struct imsg *, size_t);
122 static void		 handle_imsg_bookmark_ok(struct imsg *, size_t);
123 static void		 handle_imsg_save_cert_ok(struct imsg *, size_t);
124 static void		 handle_imsg_update_cert_ok(struct imsg *, size_t);
125 static void		 handle_imsg_session(struct imsg *, size_t);
126 static void		 handle_dispatch_imsg(int, short, void *);
127 static int		 load_about_url(struct tab *, const char *);
128 static int		 load_file_url(struct tab *, const char *);
129 static int		 load_finger_url(struct tab *, const char *);
130 static int		 load_gemini_url(struct tab *, const char *);
131 static int		 load_gopher_url(struct tab *, const char *);
132 static int		 load_via_proxy(struct tab *, const char *,
133 			     struct proxy *);
134 static int		 make_request(struct tab *, struct get_req *, int,
135 			     const char *);
136 static int		 make_fs_request(struct tab *, int, const char *);
137 static int		 do_load_url(struct tab *, const char *, const char *, int);
138 static pid_t		 start_child(enum telescope_process, const char *, int);
139 
140 static struct proto {
141 	const char	*schema;
142 	const char	*port;
143 	int		 (*loadfn)(struct tab *, const char *);
144 } protos[] = {
145 	{"about",	NULL,	load_about_url},
146 	{"file",	NULL,	load_file_url},
147 	{"finger",	"79",	load_finger_url},
148 	{"gemini",	"1965",	load_gemini_url},
149 	{"gopher",	"70",	load_gopher_url},
150 	{NULL, NULL, NULL},
151 };
152 
153 static imsg_handlerfn *handlers[] = {
154 	[IMSG_ERR] = handle_imsg_err,
155 	[IMSG_CHECK_CERT] = handle_imsg_check_cert,
156 	[IMSG_GOT_CODE] = handle_imsg_got_code,
157 	[IMSG_GOT_META] = handle_imsg_got_meta,
158 	[IMSG_BUF] = handle_imsg_buf,
159 	[IMSG_EOF] = handle_imsg_eof,
160 	[IMSG_TOFU] = handle_imsg_tofu,
161 	[IMSG_BOOKMARK_OK] = handle_imsg_bookmark_ok,
162 	[IMSG_SAVE_CERT_OK] = handle_imsg_save_cert_ok,
163 	[IMSG_UPDATE_CERT_OK] = handle_imsg_update_cert_ok,
164 	[IMSG_FILE_OPENED] = handle_imsg_file_opened,
165 	[IMSG_SESSION_TAB] = handle_imsg_session,
166 	[IMSG_SESSION_TAB_HIST] = handle_imsg_session,
167 	[IMSG_SESSION_END] = handle_imsg_session,
168 };
169 
170 static struct ohash	certs;
171 
172 static void __attribute__((__noreturn__))
173 die(void)
174 {
175 	abort(); 		/* TODO */
176 }
177 
178 static struct tab *
179 tab_by_id(uint32_t id)
180 {
181 	struct tab *t;
182 
183 	TAILQ_FOREACH(t, &tabshead, tabs) {
184 		if (t->id == id)
185 			return t;
186 	}
187 
188 	return NULL;
189 }
190 
191 static void
192 handle_imsg_err(struct imsg *imsg, size_t datalen)
193 {
194 	struct tab	*tab;
195 	char		*page;
196 
197 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL)
198 		return;
199 
200 	page = imsg->data;
201 	page[datalen-1] = '\0';
202 
203 	if (asprintf(&page, "# Error loading %s\n\n> %s\n",
204 	    tab->hist_cur->h, page) == -1)
205 		die();
206 	load_page_from_str(tab, page);
207 	free(page);
208 }
209 
210 static void
211 handle_imsg_check_cert(struct imsg *imsg, size_t datalen)
212 {
213 	const char		*hash, *host, *port;
214 	int			 tofu_res;
215 	struct tofu_entry	*e;
216 	struct tab		*tab;
217 
218 	hash = imsg->data;
219 	if (hash[datalen-1] != '\0')
220 		abort();
221 
222 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL)
223 		return;
224 
225 	if (tab->proxy != NULL) {
226 		host = tab->proxy->host;
227 		port = tab->proxy->port;
228 	} else {
229 		host = tab->uri.host;
230 		port = tab->uri.port;
231 	}
232 
233 	if ((e = tofu_lookup(&certs, host, port)) == NULL) {
234 		/* TODO: an update in libressl/libretls changed
235 		 * significantly.  Find a better approach at storing
236 		 * the certs! */
237 		if (datalen > sizeof(e->hash))
238 			abort();
239 
240 		tofu_res = 1;	/* trust on first use */
241 		if ((e = calloc(1, sizeof(*e))) == NULL)
242 			abort();
243 		strlcpy(e->domain, host, sizeof(e->domain));
244 		if (*port != '\0' && strcmp(port, "1965")) {
245 			strlcat(e->domain, ":", sizeof(e->domain));
246 			strlcat(e->domain, port, sizeof(e->domain));
247 		}
248 		strlcpy(e->hash, hash, sizeof(e->hash));
249 		tofu_add(&certs, e);
250 		ui_send_fs(IMSG_SAVE_CERT, tab->id, e, sizeof(*e));
251 	} else
252 		tofu_res = !strcmp(hash, e->hash);
253 
254 	if (tofu_res) {
255 		if (e->verified == -1)
256 			tab->trust = TS_TEMP_TRUSTED;
257 		else if (e->verified == 1)
258 			tab->trust = TS_VERIFIED;
259 		else
260 			tab->trust = TS_TRUSTED;
261 
262 		ui_send_net(IMSG_CERT_STATUS, imsg->hdr.peerid,
263 		    &tofu_res, sizeof(tofu_res));
264 	} else {
265 		tab->trust = TS_UNTRUSTED;
266 		load_page_from_str(tab, "# Certificate mismatch\n");
267 		if ((tab->cert = strdup(hash)) == NULL)
268 			die();
269 		ui_yornp("Certificate mismatch.  Proceed?",
270 		    handle_check_cert_user_choice, tab);
271 	}
272 }
273 
274 static void
275 handle_check_cert_user_choice(int accept, struct tab *tab)
276 {
277 	ui_send_net(IMSG_CERT_STATUS, tab->id, &accept,
278 	    sizeof(accept));
279 
280 	if (accept) {
281 		/*
282 		 * trust the certificate for this session only.  If
283 		 * the page results in a redirect while we're asking
284 		 * the user to save, we'll end up with an invalid
285 		 * tabid (one request == one tab id).  It also makes
286 		 * sense to save it for the current session if the
287 		 * user accepted it.
288 		 */
289 		tofu_temp_trust(&certs, tab->uri.host, tab->uri.port,
290 		    tab->cert);
291 
292 		if (!safe_mode)
293 			ui_yornp("Save the new certificate?",
294 			    handle_maybe_save_new_cert, tab);
295 		else
296 			message("Certificate temporarly trusted");
297 	} else {
298 		free(tab->cert);
299 		tab->cert = NULL;
300 	}
301 }
302 
303 static void
304 handle_maybe_save_new_cert(int accept, struct tab *tab)
305 {
306 	struct tofu_entry *e;
307 	const char *host, *port;
308 
309 	if (tab->proxy != NULL) {
310 		host = tab->proxy->host;
311 		port = tab->proxy->port;
312 	} else {
313 		host = tab->uri.host;
314 		port = tab->uri.port;
315 	}
316 
317 	if (!accept)
318 		goto end;
319 
320 	if ((e = calloc(1, sizeof(*e))) == NULL)
321 		die();
322 
323 	strlcpy(e->domain, host, sizeof(e->domain));
324 	if (*port != '\0' && strcmp(port, "1965")) {
325 		strlcat(e->domain, ":", sizeof(e->domain));
326 		strlcat(e->domain, port, sizeof(e->domain));
327 	}
328 	strlcpy(e->hash, tab->cert, sizeof(e->hash));
329 	ui_send_fs(IMSG_UPDATE_CERT, 0, e, sizeof(*e));
330 
331 	tofu_update(&certs, e);
332 
333 	tab->trust = TS_TRUSTED;
334 
335 end:
336 	free(tab->cert);
337 	tab->cert = NULL;
338 }
339 
340 static inline int
341 normalize_code(int n)
342 {
343 	if (n < 20) {
344 		if (n == 10 || n == 11)
345 			return n;
346 		return 10;
347 	} else if (n < 30) {
348 		return 20;
349 	} else if (n < 40) {
350 		if (n == 30 || n == 31)
351 			return n;
352 		return 30;
353 	} else if (n < 50) {
354 		if (n <= 44)
355 			return n;
356 		return 40;
357 	} else if (n < 60) {
358 		if (n <= 53 || n == 59)
359 			return n;
360 		return 50;
361 	} else if (n < 70) {
362 		if (n <= 62)
363 			return n;
364 		return 60;
365 	} else
366 		return MALFORMED_RESPONSE;
367 }
368 
369 static void
370 handle_imsg_got_code(struct imsg *imsg, size_t datalen)
371 {
372 	struct tab	*tab;
373 
374 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL)
375 		return;
376 
377 	if (sizeof(tab->code) != datalen)
378 		die();
379 
380 	memcpy(&tab->code, imsg->data, sizeof(tab->code));
381 	tab->code = normalize_code(tab->code);
382 	if (tab->code != 30 && tab->code != 31)
383 		tab->redirect_count = 0;
384 }
385 
386 static void
387 handle_imsg_got_meta(struct imsg *imsg, size_t datalen)
388 {
389 	struct tab	*tab;
390 	char		 buf[128];
391 
392 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL)
393 		return;
394 
395 	if (sizeof(tab->meta) <= datalen)
396 		die();
397 
398 	memcpy(tab->meta, imsg->data, datalen);
399 
400 	if (tab->code < 10) {	/* internal errors */
401 		load_page_from_str(tab, err_pages[tab->code]);
402 	} else if (tab->code < 20) {	/* 1x */
403 		load_page_from_str(tab, err_pages[tab->code]);
404 		ui_require_input(tab, tab->code == 11, PROTO_GEMINI);
405 	} else if (tab->code == 20) {
406 		if (setup_parser_for(tab)) {
407 			ui_send_net(IMSG_PROCEED, tab->id, NULL, 0);
408 		} else if (safe_mode) {
409 			load_page_from_str(tab,
410 			    err_pages[UNKNOWN_TYPE_OR_CSET]);
411 		} else {
412 			struct hist *h;
413 
414 			if ((h = hist_pop(&tab->hist)) != NULL)
415 				tab->hist_cur = h;
416 			snprintf(buf, sizeof(buf),
417 			    "Can't display \"%s\", save it?", tab->meta);
418 			ui_yornp(buf, handle_maybe_save_page, tab);
419 		}
420 	} else if (tab->code < 40) { /* 3x */
421 		tab->redirect_count++;
422 
423 		/* TODO: make customizable? */
424 		if (tab->redirect_count > 5) {
425 			load_page_from_str(tab,
426 			    err_pages[TOO_MUCH_REDIRECTS]);
427 		} else
428 			do_load_url(tab, tab->meta, NULL, LU_MODE_NOCACHE);
429 	} else { /* 4x, 5x & 6x */
430 		load_page_from_str(tab, err_pages[tab->code]);
431 	}
432 }
433 
434 static void
435 handle_maybe_save_page(int dosave, struct tab *tab)
436 {
437 	const char	*f;
438 	char		 input[PATH_MAX];
439 
440 	/* XXX: this print a message that is confusing  */
441 	ui_on_tab_loaded(tab);
442 
443 	if (!dosave) {
444 		stop_tab(tab);
445 		return;
446 	}
447 
448 	if ((f = strrchr(tab->uri.path, '/')) == NULL)
449 		f = "";
450 	else
451 		f++;
452 
453 	strlcpy(input, download_path, sizeof(input));
454 	strlcat(input, f, sizeof(input));
455 
456 	ui_read("Save to path", handle_save_page_path, tab, input);
457 }
458 
459 static void
460 handle_save_page_path(const char *path, struct tab *tab)
461 {
462 	if (path == NULL) {
463 		stop_tab(tab);
464 		return;
465 	}
466 
467 	ui_show_downloads_pane();
468 
469 	enqueue_download(tab->id, path);
470 	ui_send_fs(IMSG_FILE_OPEN, tab->id, path, strlen(path)+1);
471 
472 	/*
473 	 * Change this tab id, the old one is associated with the
474 	 * download now.
475 	 */
476 	tab->id = tab_new_id();
477 }
478 
479 static void
480 handle_imsg_file_opened(struct imsg *imsg, size_t datalen)
481 {
482 	struct download	*d;
483 	const char	*e;
484 
485 	/*
486 	 * There are no reason we shouldn't be able to find the
487 	 * required download.
488 	 */
489 	if ((d = download_by_id(imsg->hdr.peerid)) == NULL)
490 		die();
491 
492 	if (imsg->fd == -1) {
493 		e = imsg->data;
494 		if (e[datalen-1] != '\0')
495 			die();
496 		message("Can't open file %s: %s", d->path, e);
497 	} else {
498 		d->fd = imsg->fd;
499 		ui_send_net(IMSG_PROCEED, d->id, NULL, 0);
500 	}
501 }
502 
503 static void
504 handle_imsg_session(struct imsg *imsg, size_t datalen)
505 {
506 	static struct tab	*curr;
507 	static struct tab	*tab;
508 	struct session_tab	 st;
509 	struct session_tab_hist	 sth;
510 	struct hist		*h;
511 	int			 first_time;
512 
513 	/*
514 	 * The fs process tried to send tabs after it has announced
515 	 * that he's done.  Something fishy is going on, better die.
516 	 */
517 	if (operating)
518 		die();
519 
520 	switch (imsg->hdr.type) {
521 	case IMSG_SESSION_TAB:
522 		if (datalen != sizeof(st))
523 			die();
524 
525 		memcpy(&st, imsg->data, sizeof(st));
526 		if ((tab = new_tab(st.uri, NULL, NULL)) == NULL)
527 			die();
528 		tab->hist_cur->line_off = st.top_line;
529 		tab->hist_cur->current_off = st.current_line;
530 		strlcpy(tab->buffer.page.title, st.title,
531 		    sizeof(tab->buffer.page.title));
532 		if (st.flags & TAB_CURRENT)
533 			curr = tab;
534 		if (st.flags & TAB_KILLED)
535 			kill_tab(tab, 1);
536 		break;
537 
538 	case IMSG_SESSION_TAB_HIST:
539 		if (tab == NULL || datalen != sizeof(sth))
540 			die();
541 
542 		memcpy(&sth, imsg->data, sizeof(sth));
543 		if (sth.uri[sizeof(sth.uri)-1] != '\0')
544 			die();
545 
546 		if ((h = calloc(1, sizeof(*h))) == NULL)
547 			die();
548 		strlcpy(h->h, sth.uri, sizeof(h->h));
549 
550 		if (sth.future)
551 			hist_push(&tab->hist, h);
552 		else
553 			hist_add_before(&tab->hist, tab->hist_cur, h);
554 		break;
555 
556 	case IMSG_SESSION_END:
557 		if (datalen != sizeof(first_time))
558 			die();
559 		memcpy(&first_time, imsg->data, sizeof(first_time));
560 		if (first_time) {
561 			new_tab("about:new", NULL, NULL);
562 			curr = new_tab("about:help", NULL, NULL);
563 		}
564 
565 		operating = 1;
566 		if (curr != NULL)
567 			switch_to_tab(curr);
568 		if (has_url || TAILQ_EMPTY(&tabshead))
569 			new_tab(url, NULL, NULL);
570 		ui_main_loop();
571 		break;
572 
573 	default:
574 		die();
575 	}
576 }
577 
578 static void
579 handle_imsg_buf(struct imsg *imsg, size_t datalen)
580 {
581 	struct tab	*tab = NULL;
582 	struct download	*d = NULL;
583 
584 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL &&
585 	    (d = download_by_id(imsg->hdr.peerid)) == NULL)
586 		return;
587 
588 	if (tab != NULL) {
589 		if (!parser_parse(tab, imsg->data, datalen))
590 			die();
591 		ui_on_tab_refresh(tab);
592 	} else {
593 		d->bytes += datalen;
594 		write(d->fd, imsg->data, datalen);
595 		ui_on_download_refresh();
596 	}
597 }
598 
599 static void
600 handle_imsg_eof(struct imsg *imsg, size_t datalen)
601 {
602 	struct tab	*tab = NULL;
603 	struct download	*d = NULL;
604 
605 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL &&
606 	    (d = download_by_id(imsg->hdr.peerid)) == NULL)
607 		return;
608 
609 	if (tab != NULL) {
610 		if (!parser_free(tab))
611 			die();
612 		if (has_prefix(tab->hist_cur->h, "gemini://") ||
613 		    has_prefix(tab->hist_cur->h, "gopher://"))
614 			mcache_tab(tab);
615 		ui_on_tab_refresh(tab);
616 		ui_on_tab_loaded(tab);
617 	} else {
618 		close(d->fd);
619 		d->fd = -1;
620 		ui_on_download_refresh();
621 	}
622 }
623 
624 static void
625 handle_imsg_tofu(struct imsg *imsg, size_t datalen)
626 {
627 	struct tofu_entry *e;
628 
629 	if (operating)
630 		die();
631 
632 	if ((e = calloc(1, sizeof(*e))) == NULL)
633 		die();
634 
635 	if (datalen != sizeof(*e))
636 		die();
637 	memcpy(e, imsg->data, sizeof(*e));
638 	if (e->domain[sizeof(e->domain)-1] != '\0' ||
639 	    e->hash[sizeof(e->hash)-1] != '\0')
640 		die();
641 	tofu_add(&certs, e);
642 }
643 
644 static void
645 handle_imsg_bookmark_ok(struct imsg *imsg, size_t datalen)
646 {
647 	int res;
648 
649 	if (datalen != sizeof(res))
650 		die();
651 
652 	memcpy(&res, imsg->data, sizeof(res));
653 	if (res == 0)
654 		message("Added to bookmarks!");
655 	else
656 		message("Failed to add to bookmarks: %s",
657 		    strerror(res));
658 }
659 
660 static void
661 handle_imsg_save_cert_ok(struct imsg *imsg, size_t datalen)
662 {
663 	int res;
664 
665 	if (datalen != sizeof(res))
666 		die();
667 	memcpy(&res, imsg->data, datalen);
668 	if (res != 0)
669 		message("Failed to save the cert for: %s",
670 		    strerror(res));
671 }
672 
673 static void
674 handle_imsg_update_cert_ok(struct imsg *imsg, size_t datalen)
675 {
676 	int res;
677 
678 	if (datalen != sizeof(res))
679 		die();
680 	memcpy(&res, imsg->data, datalen);
681 	if (!res)
682 		message("Failed to update the certificate");
683 }
684 
685 static void
686 handle_dispatch_imsg(int fd, short ev, void *d)
687 {
688 	struct imsgev	*iev = d;
689 
690 	if (dispatch_imsg(iev, ev, handlers, sizeof(handlers)) == -1)
691 		err(1, "connection closed");
692 }
693 
694 static int
695 load_about_url(struct tab *tab, const char *url)
696 {
697 	tab->trust = TS_UNKNOWN;
698 	parser_init(tab, gemtext_initparser);
699 	return make_fs_request(tab, IMSG_GET, url);
700 }
701 
702 static int
703 load_file_url(struct tab *tab, const char *url)
704 {
705 	tab->trust = TS_UNKNOWN;
706 	return make_fs_request(tab, IMSG_GET_FILE, tab->uri.path);
707 }
708 
709 static int
710 load_finger_url(struct tab *tab, const char *url)
711 {
712 	struct get_req	 req;
713 	size_t		 len;
714 	char		*at;
715 
716 	memset(&req, 0, sizeof(req));
717 	strlcpy(req.port, tab->uri.port, sizeof(req.port));
718 
719 	/*
720 	 * Sometimes the finger url have the user as path component
721 	 * (e.g. finger://thelambdalab.xyz/plugd), sometimes as
722 	 * userinfo (e.g. finger://cobradile@finger.farm).
723 	 */
724 	if ((at = strchr(tab->uri.host, '@')) != NULL) {
725 		len = at - tab->uri.host;
726 		memcpy(req.req, tab->uri.host, len);
727 
728 		if (len >= sizeof(req.req))
729 			die();
730 		req.req[len] = '\0';
731 
732 		strlcpy(req.host, at+1, sizeof(req.host));
733 	} else {
734 		strlcpy(req.host, tab->uri.host, sizeof(req.host));
735 
736 		/* +1 to skip the initial `/' */
737 		strlcpy(req.req, tab->uri.path+1, sizeof(req.req));
738 	}
739 	strlcat(req.req, "\r\n", sizeof(req.req));
740 
741 	parser_init(tab, textplain_initparser);
742 	return make_request(tab, &req, PROTO_FINGER, NULL);
743 }
744 
745 static int
746 load_gemini_url(struct tab *tab, const char *url)
747 {
748 	struct get_req	 req;
749 
750 	memset(&req, 0, sizeof(req));
751 	strlcpy(req.host, tab->uri.host, sizeof(req.host));
752 	strlcpy(req.port, tab->uri.port, sizeof(req.port));
753 
754 	return make_request(tab, &req, PROTO_GEMINI, tab->hist_cur->h);
755 }
756 
757 static inline const char *
758 gopher_skip_selector(const char *path, int *ret_type)
759 {
760 	*ret_type = 0;
761 
762 	if (!strcmp(path, "/") || *path == '\0') {
763 		*ret_type = '1';
764 		return path;
765 	}
766 
767 	if (*path != '/')
768 		return path;
769 	path++;
770 
771 	switch (*ret_type = *path) {
772 	case '0':
773 	case '1':
774 	case '7':
775 		break;
776 
777 	default:
778 		*ret_type = 0;
779 		path -= 1;
780 		return path;
781 	}
782 
783 	return ++path;
784 }
785 
786 static int
787 load_gopher_url(struct tab *tab, const char *url)
788 {
789 	struct get_req	 req;
790 	int		 type;
791 	const char	*path;
792 
793 	memset(&req, 0, sizeof(req));
794 	strlcpy(req.host, tab->uri.host, sizeof(req.host));
795 	strlcpy(req.port, tab->uri.port, sizeof(req.port));
796 
797 	path = gopher_skip_selector(tab->uri.path, &type);
798 	switch (type) {
799 	case '0':
800 		parser_init(tab, textplain_initparser);
801 		break;
802 	case '1':
803 		parser_init(tab, gophermap_initparser);
804 		break;
805 	case '7':
806 		ui_require_input(tab, 0, PROTO_GOPHER);
807 		return load_page_from_str(tab, err_pages[10]);
808 	default:
809 		return load_page_from_str(tab, "Unknown gopher selector");
810 	}
811 
812 	strlcpy(req.req, path, sizeof(req.req));
813 	if (*tab->uri.query != '\0') {
814 		strlcat(req.req, "?", sizeof(req.req));
815 		strlcat(req.req, tab->uri.query, sizeof(req.req));
816 	}
817 	strlcat(req.req, "\r\n", sizeof(req.req));
818 
819 	return make_request(tab, &req, PROTO_GOPHER, NULL);
820 }
821 
822 static int
823 load_via_proxy(struct tab *tab, const char *url, struct proxy *p)
824 {
825 	struct get_req req;
826 
827 	memset(&req, 0, sizeof(req));
828 	strlcpy(req.host, p->host, sizeof(req.host));
829 	strlcpy(req.port, p->port, sizeof(req.port));
830 
831 	tab->proxy = p;
832 
833 	return make_request(tab, &req, p->proto, tab->hist_cur->h);
834 }
835 
836 static int
837 make_request(struct tab *tab, struct get_req *req, int proto, const char *r)
838 {
839 	stop_tab(tab);
840 	tab->id = tab_new_id();
841 	req->proto = proto;
842 
843 	if (r != NULL) {
844 		strlcpy(req->req, r, sizeof(req->req));
845 		strlcat(req->req, "\r\n", sizeof(req->req));
846 	}
847 
848 	start_loading_anim(tab);
849 	ui_send_net(IMSG_GET_RAW, tab->id, req, sizeof(*req));
850 
851 	/*
852 	 * So the various load_*_url can `return make_request` and
853 	 * do_load_url is happy.
854 	 */
855 	return 1;
856 }
857 
858 static int
859 make_fs_request(struct tab *tab, int type, const char *r)
860 {
861 	stop_tab(tab);
862 	tab->id = tab_new_id();
863 
864 	ui_send_fs(type, tab->id, r, strlen(r)+1);
865 
866 	/*
867 	 * So load_{about,file}_url can `return make_fs_request` and
868 	 * do_load_url is happy.
869 	 */
870 	return 1;
871 }
872 
873 void
874 gopher_send_search_req(struct tab *tab, const char *text)
875 {
876 	struct get_req	req;
877 
878 	memset(&req, 0, sizeof(req));
879 	strlcpy(req.host, tab->uri.host, sizeof(req.host));
880 	strlcpy(req.port, tab->uri.port, sizeof(req.port));
881 
882 	/* +2 to skip /7 */
883 	strlcpy(req.req, tab->uri.path+2, sizeof(req.req));
884 	if (*tab->uri.query != '\0') {
885 		strlcat(req.req, "?", sizeof(req.req));
886 		strlcat(req.req, tab->uri.query, sizeof(req.req));
887 	}
888 
889 	strlcat(req.req, "\t", sizeof(req.req));
890 	strlcat(req.req, text, sizeof(req.req));
891 	strlcat(req.req, "\r\n", sizeof(req.req));
892 
893 	erase_buffer(&tab->buffer);
894 	parser_init(tab, gophermap_initparser);
895 
896 	make_request(tab, &req, PROTO_GOPHER, NULL);
897 }
898 
899 /*
900  * Effectively load the given url in the given tab.  Return 1 when
901  * loading the page asynchronously, and thus when an erase_buffer can
902  * be done right after this function return, or 0 when loading the
903  * page synchronously.
904  */
905 static int
906 do_load_url(struct tab *tab, const char *url, const char *base, int mode)
907 {
908 	struct phos_uri	 uri;
909 	struct proto	*p;
910 	struct proxy	*proxy;
911 	int		 nocache = mode & LU_MODE_NOCACHE;
912 	char		*t;
913 
914 	tab->proxy = NULL;
915 	tab->trust = TS_UNKNOWN;
916 
917 	if (base == NULL)
918 		memcpy(&uri, &tab->uri, sizeof(tab->uri));
919 	else
920 		phos_parse_absolute_uri(base, &uri);
921 
922 	if (!phos_resolve_uri_from_str(&uri, url, &tab->uri)) {
923 		if (asprintf(&t, "#error loading %s\n>%s\n",
924 		    url, "Can't parse the URI") == -1)
925 			die();
926 		strlcpy(tab->hist_cur->h, url, sizeof(tab->hist_cur->h));
927 		load_page_from_str(tab, t);
928 		free(t);
929 		return 0;
930 	}
931 
932 	phos_serialize_uri(&tab->uri, tab->hist_cur->h,
933 	    sizeof(tab->hist_cur->h));
934 
935 	if (!nocache && mcache_lookup(tab->hist_cur->h, tab)) {
936 		ui_on_tab_refresh(tab);
937 		ui_on_tab_loaded(tab);
938 		return 0;
939 	}
940 
941 	for (p = protos; p->schema != NULL; ++p) {
942 		if (!strcmp(tab->uri.scheme, p->schema)) {
943 			/* patch the port */
944 			if (*tab->uri.port == '\0' && p->port != NULL)
945 				strlcpy(tab->uri.port, p->port,
946 				    sizeof(tab->uri.port));
947 
948 			return p->loadfn(tab, tab->hist_cur->h);
949 		}
950 	}
951 
952 	TAILQ_FOREACH(proxy, &proxies, proxies) {
953 		if (!strcmp(tab->uri.scheme, proxy->match_proto))
954 			return load_via_proxy(tab, url, proxy);
955 	}
956 
957 	return load_page_from_str(tab, err_pages[UNKNOWN_PROTOCOL]);
958 }
959 
960 /*
961  * Load url in tab and handle history.  If a tab is marked as lazy, only
962  * prepare the url but don't load it.
963  */
964 void
965 load_url(struct tab *tab, const char *url, const char *base, int mode)
966 {
967 	int lazy = tab->flags & TAB_LAZY;
968 	int nohist = mode & LU_MODE_NOHIST;
969 
970 	if (operating && lazy) {
971 		tab->flags ^= TAB_LAZY;
972 		lazy = 0;
973 	}
974 
975 	if (!nohist && (!lazy || tab->hist_cur == NULL)) {
976 		if (tab->hist_cur != NULL) {
977 			get_scroll_position(tab, &tab->hist_cur->line_off,
978 			    &tab->hist_cur->current_off);
979 
980 			hist_clear_forward(&tab->hist,
981 			    TAILQ_NEXT(tab->hist_cur, entries));
982 		}
983 
984 		if ((tab->hist_cur = calloc(1, sizeof(*tab->hist_cur)))
985 		    == NULL) {
986 			event_loopbreak();
987 			return;
988 		}
989 
990 		strlcpy(tab->buffer.page.title, url,
991 		    sizeof(tab->buffer.page.title));
992 		hist_push(&tab->hist, tab->hist_cur);
993 
994 		if (lazy)
995 			strlcpy(tab->hist_cur->h, url,
996 			    sizeof(tab->hist_cur->h));
997 	}
998 
999 	if (!lazy)
1000 		do_load_url(tab, url, base, mode);
1001 }
1002 
1003 void
1004 load_url_in_tab(struct tab *tab, const char *url, const char *base, int mode)
1005 {
1006 	if (operating) {
1007 		autosave_hook();
1008 		message("Loading %s...", url);
1009 	}
1010 
1011 	load_url(tab, url, base, mode);
1012 }
1013 
1014 int
1015 load_previous_page(struct tab *tab)
1016 {
1017 	struct hist	*h;
1018 
1019 	if ((h = TAILQ_PREV(tab->hist_cur, mhisthead, entries)) == NULL)
1020 		return 0;
1021 	tab->hist_cur = h;
1022 	do_load_url(tab, h->h, NULL, LU_MODE_NONE);
1023 	return 1;
1024 }
1025 
1026 int
1027 load_next_page(struct tab *tab)
1028 {
1029 	struct hist	*h;
1030 
1031 	if ((h = TAILQ_NEXT(tab->hist_cur, entries)) == NULL)
1032 		return 0;
1033 	tab->hist_cur = h;
1034 	do_load_url(tab, h->h, NULL, LU_MODE_NONE);
1035 	return 1;
1036 }
1037 
1038 void
1039 add_to_bookmarks(const char *str)
1040 {
1041 	ui_send_fs(IMSG_BOOKMARK_PAGE, 0,
1042 	    str, strlen(str)+1);
1043 }
1044 
1045 /*
1046  * Given a user-entered URL, apply some heuristics to use it:
1047  *
1048  * - if it's a proper url use it
1049  * - if it starts with a `./' or a `/' assume its a file:// url
1050  * - assume it's a gemini:// url
1051  *
1052  * `ret' (of which len is the size) will be filled with the resulting
1053  * url.
1054  */
1055 void
1056 humanify_url(const char *raw, char *ret, size_t len)
1057 {
1058 	struct phos_uri	uri;
1059 	char		buf[PATH_MAX];
1060 
1061 	if (phos_parse_absolute_uri(raw, &uri)) {
1062 		strlcpy(ret, raw, len);
1063 		return;
1064 	}
1065 
1066 	if (has_prefix(raw, "./")) {
1067 		strlcpy(ret, "file://", len);
1068 		getcwd(buf, sizeof(buf));
1069 		strlcat(ret, buf, len);
1070 		strlcat(ret, "/", len);
1071 		strlcat(ret, raw+2, len);
1072 		return;
1073 	}
1074 
1075 	if (*raw == '/') {
1076 		strlcpy(ret, "file://", len);
1077 		strlcat(ret, raw, len);
1078 		return;
1079 	}
1080 
1081 	strlcpy(ret, "gemini://", len);
1082 	strlcat(ret, raw, len);
1083 }
1084 
1085 static pid_t
1086 start_child(enum telescope_process p, const char *argv0, int fd)
1087 {
1088 	const char	*argv[5];
1089 	int		 argc = 0;
1090 	pid_t		 pid;
1091 
1092 	switch (pid = fork()) {
1093 	case -1:
1094 		die();
1095 	case 0:
1096 		break;
1097 	default:
1098 		close(fd);
1099 		return pid;
1100 	}
1101 
1102 	if (dup2(fd, 3) == -1)
1103 		err(1, "cannot setup imsg fd");
1104 
1105 	argv[argc++] = argv0;
1106 	switch (p) {
1107 	case PROC_UI:
1108 		errx(1, "Can't start ui process");
1109 	case PROC_FS:
1110 		argv[argc++] = "-Tf";
1111 		break;
1112 	case PROC_NET:
1113 		argv[argc++] = "-Tn";
1114 		break;
1115 	}
1116 
1117 	if (safe_mode)
1118 		argv[argc++] = "-S";
1119 
1120 	argv[argc++] = NULL;
1121 	execvp(argv0, (char *const *)argv);
1122 	err(1, "execvp(%s)", argv0);
1123 }
1124 
1125 int
1126 ui_send_net(int type, uint32_t peerid, const void *data,
1127     uint16_t datalen)
1128 {
1129 	return imsg_compose_event(iev_net, type, peerid, 0, -1, data,
1130 	    datalen);
1131 }
1132 
1133 int
1134 ui_send_fs(int type, uint32_t peerid, const void *data, uint16_t datalen)
1135 {
1136 	return imsg_compose_event(iev_fs, type, peerid, 0, -1, data,
1137 	    datalen);
1138 }
1139 
1140 static void __attribute__((noreturn))
1141 usage(int r)
1142 {
1143 	fprintf(stderr, "USAGE: %s [-ChnSv] [-c config] [url]\n",
1144 	    getprogname());
1145 	fprintf(stderr, "version: " PACKAGE " " VERSION "\n");
1146 	exit(r);
1147 }
1148 
1149 int
1150 main(int argc, char * const *argv)
1151 {
1152 	struct imsgev	 net_ibuf, fs_ibuf;
1153 	pid_t		 pid;
1154 	int		 pipe2net[2], pipe2fs[2];
1155 	int		 ch, configtest = 0, fail = 0;
1156 	int		 proc = -1;
1157 	int		 sessionfd = -1;
1158 	int		 status;
1159 	const char	*argv0;
1160 
1161 	argv0 = argv[0];
1162 
1163 	signal(SIGCHLD, SIG_IGN);
1164 	signal(SIGPIPE, SIG_IGN);
1165 
1166 	if (getenv("NO_COLOR") != NULL)
1167 		enable_colors = 0;
1168 
1169 	fs_init();
1170 
1171 	while ((ch = getopt_long(argc, argv, opts, longopts, NULL)) != -1) {
1172 		switch (ch) {
1173 		case 'C':
1174 			exit(ui_print_colors());
1175 		case 'c':
1176 			fail = 1;
1177 			strlcpy(config_path, optarg, sizeof(config_path));
1178 			break;
1179 		case 'n':
1180 			configtest = 1;
1181 			break;
1182 		case 'h':
1183 			usage(0);
1184 		case 'S':
1185 			safe_mode = 1;
1186 			break;
1187 		case 'T':
1188 			switch (*optarg) {
1189 			case 'f':
1190 				proc = PROC_FS;
1191 				break;
1192 			case 'n':
1193 				proc = PROC_NET;
1194 				break;
1195 			default:
1196 				errx(1, "invalid process spec %c",
1197 				    *optarg);
1198 			}
1199 			break;
1200 		case 'v':
1201 			printf("%s %s\n", PACKAGE_NAME, PACKAGE_VERSION);
1202 			exit(0);
1203 			break;
1204 		default:
1205 			usage(1);
1206 		}
1207 	}
1208 
1209 	argc -= optind;
1210 	argv += optind;
1211 
1212 	if (proc != -1) {
1213 		if (argc > 0)
1214 			usage(1);
1215 		else if (proc == PROC_FS)
1216 			return fs_main();
1217 		else if (proc == PROC_NET)
1218 			return net_main();
1219 		else
1220 			usage(1);
1221 	}
1222 
1223 	if (argc != 0) {
1224 		has_url = 1;
1225 		humanify_url(argv[0], url, sizeof(url));
1226 	}
1227 
1228 	/* setup keys before reading the config */
1229 	TAILQ_INIT(&global_map.m);
1230 	global_map.unhandled_input = global_key_unbound;
1231 	TAILQ_INIT(&minibuffer_map.m);
1232 
1233 	config_init();
1234 	parseconfig(config_path, fail);
1235 	if (configtest) {
1236 		puts("config OK");
1237 		exit(0);
1238 	}
1239 
1240 	if (download_path == NULL &&
1241 	    (download_path = strdup("/tmp/")) == NULL)
1242 		errx(1, "strdup");
1243 
1244 	if (!safe_mode && (sessionfd = lock_session()) == -1)
1245 		errx(1, "can't lock session, is another instance of "
1246 		    "telescope already running?");
1247 
1248 	/* Start children. */
1249 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pipe2fs) == -1)
1250 		err(1, "socketpair");
1251 	start_child(PROC_FS, argv0, pipe2fs[1]);
1252 	imsg_init(&fs_ibuf.ibuf, pipe2fs[0]);
1253 	iev_fs = &fs_ibuf;
1254 	iev_fs->handler = handle_dispatch_imsg;
1255 
1256 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pipe2net) == -1)
1257 		err(1, "socketpair");
1258 	start_child(PROC_NET, argv0, pipe2net[1]);
1259 	imsg_init(&net_ibuf.ibuf, pipe2net[0]);
1260 	iev_net = &net_ibuf;
1261 	iev_net->handler = handle_dispatch_imsg;
1262 
1263 	setproctitle("ui");
1264 
1265 	/* initialize tofu store */
1266 	tofu_init(&certs, 5, offsetof(struct tofu_entry, domain));
1267 
1268 	event_init();
1269 
1270 	/* initialize the in-memory cache store */
1271 	mcache_init();
1272 
1273 	/* Setup event handler for the autosave */
1274 	autosave_init();
1275 
1276 	/* Setup event handlers for pipes to fs/net */
1277 	iev_fs->events = EV_READ;
1278 	event_set(&iev_fs->ev, iev_fs->ibuf.fd, iev_fs->events,
1279 	    iev_fs->handler, iev_fs);
1280 	event_add(&iev_fs->ev, NULL);
1281 
1282 	iev_net->events = EV_READ;
1283 	event_set(&iev_net->ev, iev_net->ibuf.fd, iev_net->events,
1284 	    iev_net->handler, iev_net);
1285 	event_add(&iev_net->ev, NULL);
1286 
1287 	if (ui_init()) {
1288 		sandbox_ui_process();
1289 		ui_send_fs(IMSG_INIT, 0, NULL, 0);
1290 		event_dispatch();
1291 		ui_end();
1292 	}
1293 
1294 	ui_send_fs(IMSG_QUIT, 0, NULL, 0);
1295 	ui_send_net(IMSG_QUIT, 0, NULL, 0);
1296 	imsg_flush(&iev_fs->ibuf);
1297 	imsg_flush(&iev_net->ibuf);
1298 
1299 	/* wait for children to terminate */
1300 	do {
1301 		pid = wait(&status);
1302 		if (pid == -1) {
1303 			if (errno != EINTR && errno != ECHILD)
1304 				err(1, "wait");
1305 		} else if (WIFSIGNALED(status))
1306 			warnx("child terminated; signal %d", WTERMSIG(status));
1307 	} while (pid != -1 || (pid == -1 && errno == EINTR));
1308 
1309 	if (!safe_mode && close(sessionfd) == -1)
1310 		err(1, "close(sessionfd = %d)", sessionfd);
1311 
1312 	return 0;
1313 }