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