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/un.h>
21 #include <sys/wait.h>
22 
23 #include <errno.h>
24 #include <getopt.h>
25 #include <signal.h>
26 #include <stdio.h>
27 #include <stdlib.h>
28 #include <string.h>
29 #include <unistd.h>
30 
31 #include "control.h"
32 #include "defaults.h"
33 #include "fs.h"
34 #include "mcache.h"
35 #include "minibuffer.h"
36 #include "parser.h"
37 #include "session.h"
38 #include "telescope.h"
39 #include "ui.h"
40 #include "utils.h"
41 
42 static struct option longopts[] = {
43 	{"colors",      no_argument,    NULL,   'C'},
44 	{"colours",	no_argument,    NULL,   'C'},
45 	{"help",	no_argument,	NULL,	'h'},
46 	{"safe",	no_argument,	NULL,	'S'},
47 	{"version",	no_argument,	NULL,	'v'},
48 	{NULL,		0,		NULL,	0},
49 };
50 
51 static const char *opts = "Cc:hnST:v";
52 
53 static int	has_url;
54 static char	url[GEMINI_URL_LEN];
55 
56 /*
57  * Used to know when we're finished loading.
58  */
59 int			 operating;
60 
61 /*
62  * "Safe" (or "sandobox") mode.  If enabled, Telescope shouldn't write
63  * anything to the filesystem or execute external programs.
64  */
65 int			safe_mode;
66 
67 static struct imsgev	*iev_fs, *iev_net;
68 
69 struct tabshead		 tabshead = TAILQ_HEAD_INITIALIZER(tabshead);
70 struct tabshead		 ktabshead = TAILQ_HEAD_INITIALIZER(ktabshead);
71 struct proxylist	 proxies = TAILQ_HEAD_INITIALIZER(proxies);
72 
73 enum telescope_process {
74 	PROC_UI,
75 	PROC_FS,
76 	PROC_NET,
77 };
78 
79 #define CANNOT_FETCH		0
80 #define TOO_MUCH_REDIRECTS	1
81 #define MALFORMED_RESPONSE	2
82 #define UNKNOWN_TYPE_OR_CSET	3
83 #define UNKNOWN_PROTOCOL	4
84 
85 /* XXX: keep in sync with normalize_code */
86 const char *err_pages[70] = {
87 	[CANNOT_FETCH]		= "# Couldn't load the page\n",
88 	[TOO_MUCH_REDIRECTS]	= "# Too much redirects\n",
89 	[MALFORMED_RESPONSE]	= "# Got a malformed response\n",
90 	[UNKNOWN_TYPE_OR_CSET]	= "# Unsupported type or charset\n",
91 	[UNKNOWN_PROTOCOL]	= "# Unknown protocol\n",
92 
93 	[10] = "# Input required\n",
94 	[11] = "# Input required\n",
95 	[40] = "# Temporary failure\n",
96 	[41] = "# Server unavailable\n",
97 	[42] = "# CGI error\n",
98 	[43] = "# Proxy error\n",
99 	[44] = "# Slow down\n",
100 	[50] = "# Permanent failure\n",
101 	[51] = "# Not found\n",
102 	[52] = "# Gone\n",
103 	[53] = "# Proxy request refused\n",
104 	[59] = "# Bad request\n",
105 	[60] = "# Client certificate required\n",
106 	[61] = "# Certificate not authorised\n",
107 	[62] = "# Certificate not valid\n"
108 };
109 
110 static void		 die(void) __attribute__((__noreturn__));
111 static struct tab	*tab_by_id(uint32_t);
112 static void		 handle_imsg_err(struct imsg *, size_t);
113 static void		 handle_imsg_check_cert(struct imsg *, size_t);
114 static void		 handle_check_cert_user_choice(int, struct tab *);
115 static void		 handle_maybe_save_new_cert(int, struct tab *);
116 static void		 handle_imsg_got_code(struct imsg *, size_t);
117 static void		 handle_imsg_got_meta(struct imsg *, size_t);
118 static void		 handle_maybe_save_page(int, struct tab *);
119 static void		 handle_save_page_path(const char *, struct tab *);
120 static void		 handle_imsg_file_opened(struct imsg *, size_t);
121 static void		 handle_imsg_buf(struct imsg *, size_t);
122 static void		 handle_imsg_eof(struct imsg *, size_t);
123 static void		 handle_imsg_tofu(struct imsg *, size_t);
124 static void		 handle_imsg_bookmark_ok(struct imsg *, size_t);
125 static void		 handle_imsg_save_cert_ok(struct imsg *, size_t);
126 static void		 handle_imsg_update_cert_ok(struct imsg *, size_t);
127 static void		 handle_imsg_session(struct imsg *, size_t);
128 static void		 handle_dispatch_imsg(int, short, void *);
129 static int		 load_about_url(struct tab *, const char *);
130 static int		 load_file_url(struct tab *, const char *);
131 static int		 load_finger_url(struct tab *, const char *);
132 static int		 load_gemini_url(struct tab *, const char *);
133 static int		 load_gopher_url(struct tab *, const char *);
134 static int		 load_via_proxy(struct tab *, const char *,
135 			     struct proxy *);
136 static int		 make_request(struct tab *, struct get_req *, int,
137 			     const char *);
138 static int		 make_fs_request(struct tab *, int, const char *);
139 static int		 do_load_url(struct tab *, const char *, const char *, int);
140 static pid_t		 start_child(enum telescope_process, const char *, int);
141 static void		 send_url(const char *);
142 
143 static struct proto {
144 	const char	*schema;
145 	const char	*port;
146 	int		 (*loadfn)(struct tab *, const char *);
147 } protos[] = {
148 	{"about",	NULL,	load_about_url},
149 	{"file",	NULL,	load_file_url},
150 	{"finger",	"79",	load_finger_url},
151 	{"gemini",	"1965",	load_gemini_url},
152 	{"gopher",	"70",	load_gopher_url},
153 	{NULL, NULL, NULL},
154 };
155 
156 static imsg_handlerfn *handlers[] = {
157 	[IMSG_ERR] = handle_imsg_err,
158 	[IMSG_CHECK_CERT] = handle_imsg_check_cert,
159 	[IMSG_GOT_CODE] = handle_imsg_got_code,
160 	[IMSG_GOT_META] = handle_imsg_got_meta,
161 	[IMSG_BUF] = handle_imsg_buf,
162 	[IMSG_EOF] = handle_imsg_eof,
163 	[IMSG_TOFU] = handle_imsg_tofu,
164 	[IMSG_BOOKMARK_OK] = handle_imsg_bookmark_ok,
165 	[IMSG_SAVE_CERT_OK] = handle_imsg_save_cert_ok,
166 	[IMSG_UPDATE_CERT_OK] = handle_imsg_update_cert_ok,
167 	[IMSG_FILE_OPENED] = handle_imsg_file_opened,
168 	[IMSG_SESSION_TAB] = handle_imsg_session,
169 	[IMSG_SESSION_TAB_HIST] = handle_imsg_session,
170 	[IMSG_SESSION_END] = handle_imsg_session,
171 };
172 
173 static struct ohash	certs;
174 
175 static void __attribute__((__noreturn__))
176 die(void)
177 {
178 	abort(); 		/* TODO */
179 }
180 
181 static struct tab *
182 tab_by_id(uint32_t id)
183 {
184 	struct tab *t;
185 
186 	TAILQ_FOREACH(t, &tabshead, tabs) {
187 		if (t->id == id)
188 			return t;
189 	}
190 
191 	return NULL;
192 }
193 
194 static void
195 handle_imsg_err(struct imsg *imsg, size_t datalen)
196 {
197 	struct tab	*tab;
198 	char		*page;
199 
200 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL)
201 		return;
202 
203 	page = imsg->data;
204 	page[datalen-1] = '\0';
205 
206 	if (asprintf(&page, "# Error loading %s\n\n> %s\n",
207 	    tab->hist_cur->h, page) == -1)
208 		die();
209 	load_page_from_str(tab, page);
210 	free(page);
211 }
212 
213 static void
214 handle_imsg_check_cert(struct imsg *imsg, size_t datalen)
215 {
216 	const char		*hash, *host, *port;
217 	int			 tofu_res;
218 	struct tofu_entry	*e;
219 	struct tab		*tab;
220 
221 	hash = imsg->data;
222 	if (hash[datalen-1] != '\0')
223 		abort();
224 
225 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL)
226 		return;
227 
228 	if (tab->proxy != NULL) {
229 		host = tab->proxy->host;
230 		port = tab->proxy->port;
231 	} else {
232 		host = tab->uri.host;
233 		port = tab->uri.port;
234 	}
235 
236 	if ((e = tofu_lookup(&certs, host, port)) == NULL) {
237 		/* TODO: an update in libressl/libretls changed
238 		 * significantly.  Find a better approach at storing
239 		 * the certs! */
240 		if (datalen > sizeof(e->hash))
241 			abort();
242 
243 		tofu_res = 1;	/* trust on first use */
244 		if ((e = calloc(1, sizeof(*e))) == NULL)
245 			abort();
246 		strlcpy(e->domain, host, sizeof(e->domain));
247 		if (*port != '\0' && strcmp(port, "1965")) {
248 			strlcat(e->domain, ":", sizeof(e->domain));
249 			strlcat(e->domain, port, sizeof(e->domain));
250 		}
251 		strlcpy(e->hash, hash, sizeof(e->hash));
252 		tofu_add(&certs, e);
253 		ui_send_fs(IMSG_SAVE_CERT, tab->id, e, sizeof(*e));
254 	} else
255 		tofu_res = !strcmp(hash, e->hash);
256 
257 	if (tofu_res) {
258 		if (e->verified == -1)
259 			tab->trust = TS_TEMP_TRUSTED;
260 		else if (e->verified == 1)
261 			tab->trust = TS_VERIFIED;
262 		else
263 			tab->trust = TS_TRUSTED;
264 
265 		ui_send_net(IMSG_CERT_STATUS, imsg->hdr.peerid,
266 		    &tofu_res, sizeof(tofu_res));
267 	} else {
268 		tab->trust = TS_UNTRUSTED;
269 		load_page_from_str(tab, "# Certificate mismatch\n");
270 		if ((tab->cert = strdup(hash)) == NULL)
271 			die();
272 		ui_yornp("Certificate mismatch.  Proceed?",
273 		    handle_check_cert_user_choice, tab);
274 	}
275 }
276 
277 static void
278 handle_check_cert_user_choice(int accept, struct tab *tab)
279 {
280 	ui_send_net(IMSG_CERT_STATUS, tab->id, &accept,
281 	    sizeof(accept));
282 
283 	if (accept) {
284 		/*
285 		 * trust the certificate for this session only.  If
286 		 * the page results in a redirect while we're asking
287 		 * the user to save, we'll end up with an invalid
288 		 * tabid (one request == one tab id).  It also makes
289 		 * sense to save it for the current session if the
290 		 * user accepted it.
291 		 */
292 		tofu_temp_trust(&certs, tab->uri.host, tab->uri.port,
293 		    tab->cert);
294 
295 		if (!safe_mode)
296 			ui_yornp("Save the new certificate?",
297 			    handle_maybe_save_new_cert, tab);
298 		else
299 			message("Certificate temporarly trusted");
300 	} else {
301 		free(tab->cert);
302 		tab->cert = NULL;
303 	}
304 }
305 
306 static void
307 handle_maybe_save_new_cert(int accept, struct tab *tab)
308 {
309 	struct tofu_entry *e;
310 	const char *host, *port;
311 
312 	if (tab->proxy != NULL) {
313 		host = tab->proxy->host;
314 		port = tab->proxy->port;
315 	} else {
316 		host = tab->uri.host;
317 		port = tab->uri.port;
318 	}
319 
320 	if (!accept)
321 		goto end;
322 
323 	if ((e = calloc(1, sizeof(*e))) == NULL)
324 		die();
325 
326 	strlcpy(e->domain, host, sizeof(e->domain));
327 	if (*port != '\0' && strcmp(port, "1965")) {
328 		strlcat(e->domain, ":", sizeof(e->domain));
329 		strlcat(e->domain, port, sizeof(e->domain));
330 	}
331 	strlcpy(e->hash, tab->cert, sizeof(e->hash));
332 	ui_send_fs(IMSG_UPDATE_CERT, 0, e, sizeof(*e));
333 
334 	tofu_update(&certs, e);
335 
336 	tab->trust = TS_TRUSTED;
337 
338 end:
339 	free(tab->cert);
340 	tab->cert = NULL;
341 }
342 
343 static inline int
344 normalize_code(int n)
345 {
346 	if (n < 20) {
347 		if (n == 10 || n == 11)
348 			return n;
349 		return 10;
350 	} else if (n < 30) {
351 		return 20;
352 	} else if (n < 40) {
353 		if (n == 30 || n == 31)
354 			return n;
355 		return 30;
356 	} else if (n < 50) {
357 		if (n <= 44)
358 			return n;
359 		return 40;
360 	} else if (n < 60) {
361 		if (n <= 53 || n == 59)
362 			return n;
363 		return 50;
364 	} else if (n < 70) {
365 		if (n <= 62)
366 			return n;
367 		return 60;
368 	} else
369 		return MALFORMED_RESPONSE;
370 }
371 
372 static void
373 handle_imsg_got_code(struct imsg *imsg, size_t datalen)
374 {
375 	struct tab	*tab;
376 
377 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL)
378 		return;
379 
380 	if (sizeof(tab->code) != datalen)
381 		die();
382 
383 	memcpy(&tab->code, imsg->data, sizeof(tab->code));
384 	tab->code = normalize_code(tab->code);
385 	if (tab->code != 30 && tab->code != 31)
386 		tab->redirect_count = 0;
387 }
388 
389 static void
390 handle_imsg_got_meta(struct imsg *imsg, size_t datalen)
391 {
392 	struct tab	*tab;
393 	char		 buf[128];
394 
395 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL)
396 		return;
397 
398 	if (sizeof(tab->meta) <= datalen)
399 		die();
400 
401 	memcpy(tab->meta, imsg->data, datalen);
402 
403 	if (tab->code < 10) {	/* internal errors */
404 		load_page_from_str(tab, err_pages[tab->code]);
405 	} else if (tab->code < 20) {	/* 1x */
406 		free(tab->last_input_url);
407 		tab->last_input_url = strdup(tab->hist_cur->h);
408 		if (tab->last_input_url == NULL)
409 			die();
410 
411 		load_page_from_str(tab, err_pages[tab->code]);
412 		ui_require_input(tab, tab->code == 11, ir_select_gemini);
413 	} else if (tab->code == 20) {
414 		if (setup_parser_for(tab)) {
415 			ui_send_net(IMSG_PROCEED, tab->id, NULL, 0);
416 		} else if (safe_mode) {
417 			load_page_from_str(tab,
418 			    err_pages[UNKNOWN_TYPE_OR_CSET]);
419 		} else {
420 			struct hist *h;
421 
422 			if ((h = hist_pop(&tab->hist)) != NULL)
423 				tab->hist_cur = h;
424 			snprintf(buf, sizeof(buf),
425 			    "Can't display \"%s\", save it?", tab->meta);
426 			ui_yornp(buf, handle_maybe_save_page, tab);
427 		}
428 	} else if (tab->code < 40) { /* 3x */
429 		tab->redirect_count++;
430 
431 		/* TODO: make customizable? */
432 		if (tab->redirect_count > 5) {
433 			load_page_from_str(tab,
434 			    err_pages[TOO_MUCH_REDIRECTS]);
435 		} else
436 			do_load_url(tab, tab->meta, NULL, LU_MODE_NOCACHE);
437 	} else { /* 4x, 5x & 6x */
438 		load_page_from_str(tab, err_pages[tab->code]);
439 	}
440 }
441 
442 static void
443 handle_maybe_save_page(int dosave, struct tab *tab)
444 {
445 	const char	*f;
446 	char		 input[PATH_MAX];
447 
448 	/* XXX: this print a message that is confusing  */
449 	ui_on_tab_loaded(tab);
450 
451 	if (!dosave) {
452 		stop_tab(tab);
453 		return;
454 	}
455 
456 	if ((f = strrchr(tab->uri.path, '/')) == NULL)
457 		f = "";
458 	else
459 		f++;
460 
461 	strlcpy(input, download_path, sizeof(input));
462 	strlcat(input, f, sizeof(input));
463 
464 	ui_read("Save to path", handle_save_page_path, tab, input);
465 }
466 
467 static void
468 handle_save_page_path(const char *path, struct tab *tab)
469 {
470 	if (path == NULL) {
471 		stop_tab(tab);
472 		return;
473 	}
474 
475 	ui_show_downloads_pane();
476 
477 	enqueue_download(tab->id, path);
478 	ui_send_fs(IMSG_FILE_OPEN, tab->id, path, strlen(path)+1);
479 
480 	/*
481 	 * Change this tab id, the old one is associated with the
482 	 * download now.
483 	 */
484 	tab->id = tab_new_id();
485 }
486 
487 static void
488 handle_imsg_file_opened(struct imsg *imsg, size_t datalen)
489 {
490 	struct download	*d;
491 	const char	*e;
492 
493 	/*
494 	 * There are no reason we shouldn't be able to find the
495 	 * required download.
496 	 */
497 	if ((d = download_by_id(imsg->hdr.peerid)) == NULL)
498 		die();
499 
500 	if (imsg->fd == -1) {
501 		e = imsg->data;
502 		if (e[datalen-1] != '\0')
503 			die();
504 		message("Can't open file %s: %s", d->path, e);
505 	} else {
506 		d->fd = imsg->fd;
507 		ui_send_net(IMSG_PROCEED, d->id, NULL, 0);
508 	}
509 }
510 
511 static void
512 handle_imsg_session(struct imsg *imsg, size_t datalen)
513 {
514 	static struct tab	*curr;
515 	static struct tab	*tab;
516 	struct session_tab	 st;
517 	struct session_tab_hist	 sth;
518 	struct hist		*h;
519 	int			 first_time;
520 
521 	/*
522 	 * The fs process tried to send tabs after it has announced
523 	 * that he's done.  Something fishy is going on, better die.
524 	 */
525 	if (operating)
526 		die();
527 
528 	switch (imsg->hdr.type) {
529 	case IMSG_SESSION_TAB:
530 		if (datalen != sizeof(st))
531 			die();
532 
533 		memcpy(&st, imsg->data, sizeof(st));
534 		if ((tab = new_tab(st.uri, NULL, NULL)) == NULL)
535 			die();
536 		tab->hist_cur->line_off = st.top_line;
537 		tab->hist_cur->current_off = st.current_line;
538 		strlcpy(tab->buffer.page.title, st.title,
539 		    sizeof(tab->buffer.page.title));
540 		if (st.flags & TAB_CURRENT)
541 			curr = tab;
542 		if (st.flags & TAB_KILLED)
543 			kill_tab(tab, 1);
544 		break;
545 
546 	case IMSG_SESSION_TAB_HIST:
547 		if (tab == NULL || datalen != sizeof(sth))
548 			die();
549 
550 		memcpy(&sth, imsg->data, sizeof(sth));
551 		if (sth.uri[sizeof(sth.uri)-1] != '\0')
552 			die();
553 
554 		if ((h = calloc(1, sizeof(*h))) == NULL)
555 			die();
556 		strlcpy(h->h, sth.uri, sizeof(h->h));
557 
558 		if (sth.future)
559 			hist_push(&tab->hist, h);
560 		else
561 			hist_add_before(&tab->hist, tab->hist_cur, h);
562 		break;
563 
564 	case IMSG_SESSION_END:
565 		if (datalen != sizeof(first_time))
566 			die();
567 		memcpy(&first_time, imsg->data, sizeof(first_time));
568 		if (first_time) {
569 			new_tab("about:new", NULL, NULL);
570 			curr = new_tab("about:help", NULL, NULL);
571 		}
572 
573 		operating = 1;
574 		if (curr != NULL)
575 			switch_to_tab(curr);
576 		if (has_url || TAILQ_EMPTY(&tabshead))
577 			new_tab(url, NULL, NULL);
578 		ui_main_loop();
579 		break;
580 
581 	default:
582 		die();
583 	}
584 }
585 
586 static void
587 handle_imsg_buf(struct imsg *imsg, size_t datalen)
588 {
589 	struct tab	*tab = NULL;
590 	struct download	*d = NULL;
591 
592 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL &&
593 	    (d = download_by_id(imsg->hdr.peerid)) == NULL)
594 		return;
595 
596 	if (tab != NULL) {
597 		if (!parser_parse(tab, imsg->data, datalen))
598 			die();
599 		ui_on_tab_refresh(tab);
600 	} else {
601 		d->bytes += datalen;
602 		write(d->fd, imsg->data, datalen);
603 		ui_on_download_refresh();
604 	}
605 }
606 
607 static void
608 handle_imsg_eof(struct imsg *imsg, size_t datalen)
609 {
610 	struct tab	*tab = NULL;
611 	struct download	*d = NULL;
612 
613 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL &&
614 	    (d = download_by_id(imsg->hdr.peerid)) == NULL)
615 		return;
616 
617 	if (tab != NULL) {
618 		if (!parser_free(tab))
619 			die();
620 		if (has_prefix(tab->hist_cur->h, "gemini://") ||
621 		    has_prefix(tab->hist_cur->h, "gopher://"))
622 			mcache_tab(tab);
623 		ui_on_tab_refresh(tab);
624 		ui_on_tab_loaded(tab);
625 	} else {
626 		close(d->fd);
627 		d->fd = -1;
628 		ui_on_download_refresh();
629 	}
630 }
631 
632 static void
633 handle_imsg_tofu(struct imsg *imsg, size_t datalen)
634 {
635 	struct tofu_entry *e;
636 
637 	if (operating)
638 		die();
639 
640 	if ((e = calloc(1, sizeof(*e))) == NULL)
641 		die();
642 
643 	if (datalen != sizeof(*e))
644 		die();
645 	memcpy(e, imsg->data, sizeof(*e));
646 	if (e->domain[sizeof(e->domain)-1] != '\0' ||
647 	    e->hash[sizeof(e->hash)-1] != '\0')
648 		die();
649 	tofu_add(&certs, e);
650 }
651 
652 static void
653 handle_imsg_bookmark_ok(struct imsg *imsg, size_t datalen)
654 {
655 	int res;
656 
657 	if (datalen != sizeof(res))
658 		die();
659 
660 	memcpy(&res, imsg->data, sizeof(res));
661 	if (res == 0)
662 		message("Added to bookmarks!");
663 	else
664 		message("Failed to add to bookmarks: %s",
665 		    strerror(res));
666 }
667 
668 static void
669 handle_imsg_save_cert_ok(struct imsg *imsg, size_t datalen)
670 {
671 	int res;
672 
673 	if (datalen != sizeof(res))
674 		die();
675 	memcpy(&res, imsg->data, datalen);
676 	if (res != 0)
677 		message("Failed to save the cert for: %s",
678 		    strerror(res));
679 }
680 
681 static void
682 handle_imsg_update_cert_ok(struct imsg *imsg, size_t datalen)
683 {
684 	int res;
685 
686 	if (datalen != sizeof(res))
687 		die();
688 	memcpy(&res, imsg->data, datalen);
689 	if (!res)
690 		message("Failed to update the certificate");
691 }
692 
693 static void
694 handle_dispatch_imsg(int fd, short ev, void *d)
695 {
696 	struct imsgev	*iev = d;
697 
698 	if (dispatch_imsg(iev, ev, handlers, sizeof(handlers)) == -1)
699 		err(1, "connection closed");
700 }
701 
702 static int
703 load_about_url(struct tab *tab, const char *url)
704 {
705 	tab->trust = TS_UNKNOWN;
706 	parser_init(tab, gemtext_initparser);
707 	return make_fs_request(tab, IMSG_GET, url);
708 }
709 
710 static int
711 load_file_url(struct tab *tab, const char *url)
712 {
713 	tab->trust = TS_UNKNOWN;
714 	return make_fs_request(tab, IMSG_GET_FILE, tab->uri.path);
715 }
716 
717 static int
718 load_finger_url(struct tab *tab, const char *url)
719 {
720 	struct get_req	 req;
721 	size_t		 len;
722 	char		*at;
723 
724 	memset(&req, 0, sizeof(req));
725 	strlcpy(req.port, tab->uri.port, sizeof(req.port));
726 
727 	/*
728 	 * Sometimes the finger url have the user as path component
729 	 * (e.g. finger://thelambdalab.xyz/plugd), sometimes as
730 	 * userinfo (e.g. finger://cobradile@finger.farm).
731 	 */
732 	if ((at = strchr(tab->uri.host, '@')) != NULL) {
733 		len = at - tab->uri.host;
734 		memcpy(req.req, tab->uri.host, len);
735 
736 		if (len >= sizeof(req.req))
737 			die();
738 		req.req[len] = '\0';
739 
740 		strlcpy(req.host, at+1, sizeof(req.host));
741 	} else {
742 		strlcpy(req.host, tab->uri.host, sizeof(req.host));
743 
744 		/* +1 to skip the initial `/' */
745 		strlcpy(req.req, tab->uri.path+1, sizeof(req.req));
746 	}
747 	strlcat(req.req, "\r\n", sizeof(req.req));
748 
749 	parser_init(tab, textplain_initparser);
750 	return make_request(tab, &req, PROTO_FINGER, NULL);
751 }
752 
753 static int
754 load_gemini_url(struct tab *tab, const char *url)
755 {
756 	struct get_req	 req;
757 
758 	memset(&req, 0, sizeof(req));
759 	strlcpy(req.host, tab->uri.host, sizeof(req.host));
760 	strlcpy(req.port, tab->uri.port, sizeof(req.port));
761 
762 	return make_request(tab, &req, PROTO_GEMINI, tab->hist_cur->h);
763 }
764 
765 static inline const char *
766 gopher_skip_selector(const char *path, int *ret_type)
767 {
768 	*ret_type = 0;
769 
770 	if (!strcmp(path, "/") || *path == '\0') {
771 		*ret_type = '1';
772 		return path;
773 	}
774 
775 	if (*path != '/')
776 		return path;
777 	path++;
778 
779 	switch (*ret_type = *path) {
780 	case '0':
781 	case '1':
782 	case '7':
783 		break;
784 
785 	default:
786 		*ret_type = 0;
787 		path -= 1;
788 		return path;
789 	}
790 
791 	return ++path;
792 }
793 
794 static int
795 load_gopher_url(struct tab *tab, const char *url)
796 {
797 	struct get_req	 req;
798 	int		 type;
799 	const char	*path;
800 
801 	memset(&req, 0, sizeof(req));
802 	strlcpy(req.host, tab->uri.host, sizeof(req.host));
803 	strlcpy(req.port, tab->uri.port, sizeof(req.port));
804 
805 	path = gopher_skip_selector(tab->uri.path, &type);
806 	switch (type) {
807 	case '0':
808 		parser_init(tab, textplain_initparser);
809 		break;
810 	case '1':
811 		parser_init(tab, gophermap_initparser);
812 		break;
813 	case '7':
814 		free(tab->last_input_url);
815 		tab->last_input_url = strdup(url);
816 		if (tab->last_input_url == NULL)
817 			die();
818 		ui_require_input(tab, 0, ir_select_gopher);
819 		return load_page_from_str(tab, err_pages[10]);
820 	default:
821 		return load_page_from_str(tab, "Unknown gopher selector");
822 	}
823 
824 	strlcpy(req.req, path, 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 	strlcat(req.req, "\r\n", sizeof(req.req));
830 
831 	return make_request(tab, &req, PROTO_GOPHER, NULL);
832 }
833 
834 static int
835 load_via_proxy(struct tab *tab, const char *url, struct proxy *p)
836 {
837 	struct get_req req;
838 
839 	memset(&req, 0, sizeof(req));
840 	strlcpy(req.host, p->host, sizeof(req.host));
841 	strlcpy(req.port, p->port, sizeof(req.port));
842 
843 	tab->proxy = p;
844 
845 	return make_request(tab, &req, p->proto, tab->hist_cur->h);
846 }
847 
848 static int
849 make_request(struct tab *tab, struct get_req *req, int proto, const char *r)
850 {
851 	stop_tab(tab);
852 	tab->id = tab_new_id();
853 	req->proto = proto;
854 
855 	if (r != NULL) {
856 		strlcpy(req->req, r, sizeof(req->req));
857 		strlcat(req->req, "\r\n", sizeof(req->req));
858 	}
859 
860 	start_loading_anim(tab);
861 	ui_send_net(IMSG_GET_RAW, tab->id, req, sizeof(*req));
862 
863 	/*
864 	 * So the various load_*_url can `return make_request` and
865 	 * do_load_url is happy.
866 	 */
867 	return 1;
868 }
869 
870 static int
871 make_fs_request(struct tab *tab, int type, const char *r)
872 {
873 	stop_tab(tab);
874 	tab->id = tab_new_id();
875 
876 	ui_send_fs(type, tab->id, r, strlen(r)+1);
877 
878 	/*
879 	 * So load_{about,file}_url can `return make_fs_request` and
880 	 * do_load_url is happy.
881 	 */
882 	return 1;
883 }
884 
885 void
886 gopher_send_search_req(struct tab *tab, const char *text)
887 {
888 	struct get_req	req;
889 
890 	memset(&req, 0, sizeof(req));
891 	strlcpy(req.host, tab->uri.host, sizeof(req.host));
892 	strlcpy(req.port, tab->uri.port, sizeof(req.port));
893 
894 	/* +2 to skip /7 */
895 	strlcpy(req.req, tab->uri.path+2, sizeof(req.req));
896 	if (*tab->uri.query != '\0') {
897 		strlcat(req.req, "?", sizeof(req.req));
898 		strlcat(req.req, tab->uri.query, sizeof(req.req));
899 	}
900 
901 	strlcat(req.req, "\t", sizeof(req.req));
902 	strlcat(req.req, text, sizeof(req.req));
903 	strlcat(req.req, "\r\n", sizeof(req.req));
904 
905 	erase_buffer(&tab->buffer);
906 	parser_init(tab, gophermap_initparser);
907 
908 	make_request(tab, &req, PROTO_GOPHER, NULL);
909 }
910 
911 int
912 load_page_from_str(struct tab *tab, const char *page)
913 {
914 	parser_init(tab, gemtext_initparser);
915 	if (!tab->buffer.page.parse(&tab->buffer.page, page, strlen(page)))
916 		abort();
917 	if (!tab->buffer.page.free(&tab->buffer.page))
918 		abort();
919 	ui_on_tab_refresh(tab);
920 	ui_on_tab_loaded(tab);
921 	return 0;
922 }
923 
924 /*
925  * Effectively load the given url in the given tab.  Return 1 when
926  * loading the page asynchronously, and thus when an erase_buffer can
927  * be done right after this function return, or 0 when loading the
928  * page synchronously.
929  */
930 static int
931 do_load_url(struct tab *tab, const char *url, const char *base, int mode)
932 {
933 	struct phos_uri	 uri;
934 	struct proto	*p;
935 	struct proxy	*proxy;
936 	int		 nocache = mode & LU_MODE_NOCACHE;
937 	char		*t;
938 
939 	tab->proxy = NULL;
940 	tab->trust = TS_UNKNOWN;
941 
942 	if (base == NULL)
943 		memcpy(&uri, &tab->uri, sizeof(tab->uri));
944 	else
945 		phos_parse_absolute_uri(base, &uri);
946 
947 	if (!phos_resolve_uri_from_str(&uri, url, &tab->uri)) {
948 		if (asprintf(&t, "#error loading %s\n>%s\n",
949 		    url, "Can't parse the URI") == -1)
950 			die();
951 		strlcpy(tab->hist_cur->h, url, sizeof(tab->hist_cur->h));
952 		load_page_from_str(tab, t);
953 		free(t);
954 		return 0;
955 	}
956 
957 	phos_serialize_uri(&tab->uri, tab->hist_cur->h,
958 	    sizeof(tab->hist_cur->h));
959 
960 	if (!nocache && mcache_lookup(tab->hist_cur->h, tab)) {
961 		ui_on_tab_refresh(tab);
962 		ui_on_tab_loaded(tab);
963 		return 0;
964 	}
965 
966 	for (p = protos; p->schema != NULL; ++p) {
967 		if (!strcmp(tab->uri.scheme, p->schema)) {
968 			/* patch the port */
969 			if (*tab->uri.port == '\0' && p->port != NULL)
970 				strlcpy(tab->uri.port, p->port,
971 				    sizeof(tab->uri.port));
972 
973 			return p->loadfn(tab, tab->hist_cur->h);
974 		}
975 	}
976 
977 	TAILQ_FOREACH(proxy, &proxies, proxies) {
978 		if (!strcmp(tab->uri.scheme, proxy->match_proto))
979 			return load_via_proxy(tab, url, proxy);
980 	}
981 
982 	return load_page_from_str(tab, err_pages[UNKNOWN_PROTOCOL]);
983 }
984 
985 /*
986  * Load url in tab and handle history.  If a tab is marked as lazy, only
987  * prepare the url but don't load it.
988  */
989 void
990 load_url(struct tab *tab, const char *url, const char *base, int mode)
991 {
992 	int lazy = tab->flags & TAB_LAZY;
993 	int nohist = mode & LU_MODE_NOHIST;
994 
995 	if (operating && lazy) {
996 		tab->flags ^= TAB_LAZY;
997 		lazy = 0;
998 	} else if (tab->hist_cur != NULL)
999 		get_scroll_position(tab, &tab->hist_cur->line_off,
1000 		    &tab->hist_cur->current_off);
1001 
1002 	if (!nohist && (!lazy || tab->hist_cur == NULL)) {
1003 		if (tab->hist_cur != NULL)
1004 			hist_clear_forward(&tab->hist,
1005 			    TAILQ_NEXT(tab->hist_cur, entries));
1006 
1007 		if ((tab->hist_cur = calloc(1, sizeof(*tab->hist_cur)))
1008 		    == NULL) {
1009 			event_loopbreak();
1010 			return;
1011 		}
1012 
1013 		strlcpy(tab->buffer.page.title, url,
1014 		    sizeof(tab->buffer.page.title));
1015 		hist_push(&tab->hist, tab->hist_cur);
1016 
1017 		if (lazy)
1018 			strlcpy(tab->hist_cur->h, url,
1019 			    sizeof(tab->hist_cur->h));
1020 	}
1021 
1022 	if (!lazy)
1023 		do_load_url(tab, url, base, mode);
1024 }
1025 
1026 void
1027 load_url_in_tab(struct tab *tab, const char *url, const char *base, int mode)
1028 {
1029 	if (operating) {
1030 		autosave_hook();
1031 		message("Loading %s...", url);
1032 	}
1033 
1034 	load_url(tab, url, base, mode);
1035 }
1036 
1037 int
1038 load_previous_page(struct tab *tab)
1039 {
1040 	struct hist	*h;
1041 
1042 	if ((h = TAILQ_PREV(tab->hist_cur, mhisthead, entries)) == NULL)
1043 		return 0;
1044 	tab->hist_cur = h;
1045 	do_load_url(tab, h->h, NULL, LU_MODE_NONE);
1046 	return 1;
1047 }
1048 
1049 int
1050 load_next_page(struct tab *tab)
1051 {
1052 	struct hist	*h;
1053 
1054 	if ((h = TAILQ_NEXT(tab->hist_cur, entries)) == NULL)
1055 		return 0;
1056 	tab->hist_cur = h;
1057 	do_load_url(tab, h->h, NULL, LU_MODE_NONE);
1058 	return 1;
1059 }
1060 
1061 void
1062 add_to_bookmarks(const char *str)
1063 {
1064 	ui_send_fs(IMSG_BOOKMARK_PAGE, 0,
1065 	    str, strlen(str)+1);
1066 }
1067 
1068 /*
1069  * Given a user-entered URL, apply some heuristics to use it:
1070  *
1071  * - if it's a proper url use it
1072  * - if it starts with a `./' or a `/' assume its a file:// url
1073  * - assume it's a gemini:// url
1074  *
1075  * `ret' (of which len is the size) will be filled with the resulting
1076  * url.
1077  */
1078 void
1079 humanify_url(const char *raw, char *ret, size_t len)
1080 {
1081 	struct phos_uri	uri;
1082 	char		buf[PATH_MAX];
1083 
1084 	if (phos_parse_absolute_uri(raw, &uri)) {
1085 		strlcpy(ret, raw, len);
1086 		return;
1087 	}
1088 
1089 	if (has_prefix(raw, "./")) {
1090 		strlcpy(ret, "file://", len);
1091 		getcwd(buf, sizeof(buf));
1092 		strlcat(ret, buf, len);
1093 		strlcat(ret, "/", len);
1094 		strlcat(ret, raw+2, len);
1095 		return;
1096 	}
1097 
1098 	if (*raw == '/') {
1099 		strlcpy(ret, "file://", len);
1100 		strlcat(ret, raw, len);
1101 		return;
1102 	}
1103 
1104 	strlcpy(ret, "gemini://", len);
1105 	strlcat(ret, raw, len);
1106 }
1107 
1108 static pid_t
1109 start_child(enum telescope_process p, const char *argv0, int fd)
1110 {
1111 	const char	*argv[5];
1112 	int		 argc = 0;
1113 	pid_t		 pid;
1114 
1115 	switch (pid = fork()) {
1116 	case -1:
1117 		die();
1118 	case 0:
1119 		break;
1120 	default:
1121 		close(fd);
1122 		return pid;
1123 	}
1124 
1125 	if (dup2(fd, 3) == -1)
1126 		err(1, "cannot setup imsg fd");
1127 
1128 	argv[argc++] = argv0;
1129 	switch (p) {
1130 	case PROC_UI:
1131 		errx(1, "Can't start ui process");
1132 	case PROC_FS:
1133 		argv[argc++] = "-Tf";
1134 		break;
1135 	case PROC_NET:
1136 		argv[argc++] = "-Tn";
1137 		break;
1138 	}
1139 
1140 	if (safe_mode)
1141 		argv[argc++] = "-S";
1142 
1143 	argv[argc++] = NULL;
1144 	execvp(argv0, (char *const *)argv);
1145 	err(1, "execvp(%s)", argv0);
1146 }
1147 
1148 static void
1149 send_url(const char *url)
1150 {
1151 	struct sockaddr_un	 sun;
1152 	struct imsgbuf		 ibuf;
1153 	int			 ctl_sock;
1154 
1155 	if ((ctl_sock = socket(AF_UNIX, SOCK_STREAM, 0)) == -1)
1156 		err(1, "socket");
1157 
1158 	memset(&sun, 0, sizeof(sun));
1159 	sun.sun_family = AF_UNIX;
1160 	strlcpy(sun.sun_path, ctlsock_path, sizeof(sun.sun_path));
1161 
1162 	if (connect(ctl_sock, (struct sockaddr *)&sun, sizeof(sun)) == -1)
1163 		err(1, "connect: %s", ctlsock_path);
1164 
1165 	imsg_init(&ibuf, ctl_sock);
1166 	imsg_compose(&ibuf, IMSG_CTL_OPEN_URL, 0, 0, -1, url,
1167 	    strlen(url) + 1);
1168 	imsg_flush(&ibuf);
1169 	close(ctl_sock);
1170 }
1171 
1172 int
1173 ui_send_net(int type, uint32_t peerid, const void *data,
1174     uint16_t datalen)
1175 {
1176 	return imsg_compose_event(iev_net, type, peerid, 0, -1, data,
1177 	    datalen);
1178 }
1179 
1180 int
1181 ui_send_fs(int type, uint32_t peerid, const void *data, uint16_t datalen)
1182 {
1183 	return imsg_compose_event(iev_fs, type, peerid, 0, -1, data,
1184 	    datalen);
1185 }
1186 
1187 static void __attribute__((noreturn))
1188 usage(int r)
1189 {
1190 	fprintf(stderr, "USAGE: %s [-ChnSv] [-c config] [url]\n",
1191 	    getprogname());
1192 	fprintf(stderr, "version: " PACKAGE " " VERSION "\n");
1193 	exit(r);
1194 }
1195 
1196 int
1197 main(int argc, char * const *argv)
1198 {
1199 	struct imsgev	 net_ibuf, fs_ibuf;
1200 	pid_t		 pid;
1201 	int		 control_fd;
1202 	int		 pipe2net[2], pipe2fs[2];
1203 	int		 ch, configtest = 0, fail = 0;
1204 	int		 proc = -1;
1205 	int		 sessionfd = -1;
1206 	int		 status;
1207 	const char	*argv0;
1208 
1209 	argv0 = argv[0];
1210 
1211 	signal(SIGCHLD, SIG_IGN);
1212 	signal(SIGPIPE, SIG_IGN);
1213 
1214 	if (getenv("NO_COLOR") != NULL)
1215 		enable_colors = 0;
1216 
1217 	fs_init();
1218 
1219 	while ((ch = getopt_long(argc, argv, opts, longopts, NULL)) != -1) {
1220 		switch (ch) {
1221 		case 'C':
1222 			exit(ui_print_colors());
1223 		case 'c':
1224 			fail = 1;
1225 			strlcpy(config_path, optarg, sizeof(config_path));
1226 			break;
1227 		case 'n':
1228 			configtest = 1;
1229 			break;
1230 		case 'h':
1231 			usage(0);
1232 		case 'S':
1233 			safe_mode = 1;
1234 			break;
1235 		case 'T':
1236 			switch (*optarg) {
1237 			case 'f':
1238 				proc = PROC_FS;
1239 				break;
1240 			case 'n':
1241 				proc = PROC_NET;
1242 				break;
1243 			default:
1244 				errx(1, "invalid process spec %c",
1245 				    *optarg);
1246 			}
1247 			break;
1248 		case 'v':
1249 			printf("%s %s\n", PACKAGE_NAME, PACKAGE_VERSION);
1250 			exit(0);
1251 			break;
1252 		default:
1253 			usage(1);
1254 		}
1255 	}
1256 
1257 	argc -= optind;
1258 	argv += optind;
1259 
1260 	if (proc != -1) {
1261 		if (argc > 0)
1262 			usage(1);
1263 		else if (proc == PROC_FS)
1264 			return fs_main();
1265 		else if (proc == PROC_NET)
1266 			return net_main();
1267 		else
1268 			usage(1);
1269 	}
1270 
1271 	if (argc != 0) {
1272 		has_url = 1;
1273 		humanify_url(argv[0], url, sizeof(url));
1274 	}
1275 
1276 	/* setup keys before reading the config */
1277 	TAILQ_INIT(&global_map.m);
1278 	global_map.unhandled_input = global_key_unbound;
1279 	TAILQ_INIT(&minibuffer_map.m);
1280 
1281 	config_init();
1282 	parseconfig(config_path, fail);
1283 	if (configtest) {
1284 		puts("config OK");
1285 		exit(0);
1286 	}
1287 
1288 	if (download_path == NULL &&
1289 	    (download_path = strdup("/tmp/")) == NULL)
1290 		errx(1, "strdup");
1291 
1292 	if (!safe_mode && (sessionfd = lock_session()) == -1) {
1293 		if (has_url) {
1294 			send_url(url);
1295 			exit(0);
1296 		}
1297 
1298 		errx(1, "can't lock session, is another instance of "
1299 		    "telescope already running?");
1300 	}
1301 
1302 	/* Start children. */
1303 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pipe2fs) == -1)
1304 		err(1, "socketpair");
1305 	start_child(PROC_FS, argv0, pipe2fs[1]);
1306 	imsg_init(&fs_ibuf.ibuf, pipe2fs[0]);
1307 	iev_fs = &fs_ibuf;
1308 	iev_fs->handler = handle_dispatch_imsg;
1309 
1310 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pipe2net) == -1)
1311 		err(1, "socketpair");
1312 	start_child(PROC_NET, argv0, pipe2net[1]);
1313 	imsg_init(&net_ibuf.ibuf, pipe2net[0]);
1314 	iev_net = &net_ibuf;
1315 	iev_net->handler = handle_dispatch_imsg;
1316 
1317 	setproctitle("ui");
1318 
1319 	/* initialize tofu store */
1320 	tofu_init(&certs, 5, offsetof(struct tofu_entry, domain));
1321 
1322 	event_init();
1323 
1324 	if (!safe_mode) {
1325 		if ((control_fd = control_init(ctlsock_path)) == -1)
1326 			err(1, "control_init %s", ctlsock_path);
1327 		control_listen(control_fd);
1328 	}
1329 
1330 	/* initialize the in-memory cache store */
1331 	mcache_init();
1332 
1333 	/* Setup event handler for the autosave */
1334 	autosave_init();
1335 
1336 	/* Setup event handlers for pipes to fs/net */
1337 	iev_fs->events = EV_READ;
1338 	event_set(&iev_fs->ev, iev_fs->ibuf.fd, iev_fs->events,
1339 	    iev_fs->handler, iev_fs);
1340 	event_add(&iev_fs->ev, NULL);
1341 
1342 	iev_net->events = EV_READ;
1343 	event_set(&iev_net->ev, iev_net->ibuf.fd, iev_net->events,
1344 	    iev_net->handler, iev_net);
1345 	event_add(&iev_net->ev, NULL);
1346 
1347 	if (ui_init()) {
1348 		sandbox_ui_process();
1349 		ui_send_fs(IMSG_INIT, 0, NULL, 0);
1350 		event_dispatch();
1351 		ui_end();
1352 	}
1353 
1354 	ui_send_fs(IMSG_QUIT, 0, NULL, 0);
1355 	ui_send_net(IMSG_QUIT, 0, NULL, 0);
1356 	imsg_flush(&iev_fs->ibuf);
1357 	imsg_flush(&iev_net->ibuf);
1358 
1359 	/* wait for children to terminate */
1360 	do {
1361 		pid = wait(&status);
1362 		if (pid == -1) {
1363 			if (errno != EINTR && errno != ECHILD)
1364 				err(1, "wait");
1365 		} else if (WIFSIGNALED(status))
1366 			warnx("child terminated; signal %d", WTERMSIG(status));
1367 	} while (pid != -1 || (pid == -1 && errno == EINTR));
1368 
1369 	if (!safe_mode && close(sessionfd) == -1)
1370 		err(1, "close(sessionfd = %d)", sessionfd);
1371 
1372 	return 0;
1373 }