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 <sys/socket.h>
18 
19 #include <errno.h>
20 #include <getopt.h>
21 #include <limits.h>
22 #include <signal.h>
23 #include <stdio.h>
24 #include <stdlib.h>
25 #include <string.h>
26 #include <unistd.h>
27 
28 #include "defaults.h"
29 #include "parser.h"
30 #include "telescope.h"
31 #include "ui.h"
32 
33 static struct option longopts[] = {
34 	{"colors",	no_argument,	NULL,	'c'},
35 	{"help",	no_argument,	NULL,	'h'},
36 	{"version",	no_argument,	NULL,	'v'},
37 	{NULL,		0,		NULL,	0},
38 };
39 
40 static const char *opts = "Cc:hnT:v";
41 
42 static struct imsgev	*iev_fs, *iev_net;
43 
44 struct tabshead		 tabshead = TAILQ_HEAD_INITIALIZER(tabshead);
45 struct proxylist	 proxies = TAILQ_HEAD_INITIALIZER(proxies);
46 
47 enum telescope_process {
48 	PROC_UI,
49 	PROC_FS,
50 	PROC_NET,
51 };
52 
53 /* the first is also the fallback one */
54 static struct proto protos[] = {
55 	{ "gemini",	load_gemini_url },
56 	{ "about",	load_about_url },
57 	{ NULL, NULL },
58 };
59 
60 
61 #define CANNOT_FETCH		0
62 #define TOO_MUCH_REDIRECTS	1
63 #define MALFORMED_RESPONSE	2
64 #define UNKNOWN_TYPE_OR_CSET	3
65 #define UNKNOWN_PROTOCOL	4
66 
67 /* XXX: keep in sync with telescope.c:/^normalize_code/ */
68 const char *err_pages[70] = {
69 	[CANNOT_FETCH]		= "# Couldn't load the page\n",
70 	[TOO_MUCH_REDIRECTS]	= "# Too much redirects\n",
71 	[MALFORMED_RESPONSE]	= "# Got a malformed response\n",
72 	[UNKNOWN_TYPE_OR_CSET]	= "# Unsupported type or charset\n",
73 	[UNKNOWN_PROTOCOL]	= "# Unknown protocol\n",
74 
75 	[10] = "# Input required\n",
76 	[11] = "# Input required\n",
77 	[40] = "# Temporary failure\n",
78 	[41] = "# Server unavailable\n",
79 	[42] = "# CGI error\n",
80 	[43] = "# Proxy error\n",
81 	[44] = "# Slow down\n",
82 	[50] = "# Permanent failure\n",
83 	[51] = "# Not found\n",
84 	[52] = "# Gone\n",
85 	[53] = "# Proxy request refused\n",
86 	[59] = "# Bad request\n",
87 	[60] = "# Client certificate required\n",
88 	[61] = "# Certificate not authorised\n",
89 	[62] = "# Certificate not valid\n"
90 };
91 
92 static void		 die(void) __attribute__((__noreturn__));
93 static struct tab	*tab_by_id(uint32_t);
94 static void		 handle_imsg_err(struct imsg*, size_t);
95 static void		 handle_imsg_check_cert(struct imsg*, size_t);
96 static void		 handle_check_cert_user_choice(int, struct tab *);
97 static void		 handle_maybe_save_new_cert(int, struct tab *);
98 static void		 handle_imsg_got_code(struct imsg*, size_t);
99 static void		 handle_imsg_got_meta(struct imsg*, size_t);
100 static void		 handle_maybe_save_page(int, struct tab *);
101 static void		 handle_save_page_path(const char *, struct tab *);
102 static void		 handle_imsg_file_opened(struct imsg*, size_t);
103 static void		 handle_imsg_buf(struct imsg*, size_t);
104 static void		 handle_imsg_eof(struct imsg*, size_t);
105 static void		 handle_imsg_bookmark_ok(struct imsg*, size_t);
106 static void		 handle_imsg_save_cert_ok(struct imsg*, size_t);
107 static void		 handle_imsg_update_cert_ok(struct imsg *, size_t);
108 static void		 handle_dispatch_imsg(int, short, void*);
109 static void		 load_page_from_str(struct tab*, const char*);
110 static int		 do_load_url(struct tab*, const char*);
111 static void		 parse_session_line(char *, const char **, uint32_t *);
112 static void		 load_last_session(void);
113 static pid_t		 start_child(enum telescope_process, const char *, int);
114 static int		 ui_send_net(int, uint32_t, const void *, uint16_t);
115 static int		 ui_send_fs(int, uint32_t, const void *, uint16_t);
116 
117 static imsg_handlerfn *handlers[] = {
118 	[IMSG_ERR] = handle_imsg_err,
119 	[IMSG_CHECK_CERT] = handle_imsg_check_cert,
120 	[IMSG_GOT_CODE] = handle_imsg_got_code,
121 	[IMSG_GOT_META] = handle_imsg_got_meta,
122 	[IMSG_BUF] = handle_imsg_buf,
123 	[IMSG_EOF] = handle_imsg_eof,
124 	[IMSG_BOOKMARK_OK] = handle_imsg_bookmark_ok,
125 	[IMSG_SAVE_CERT_OK] = handle_imsg_save_cert_ok,
126 	[IMSG_UPDATE_CERT_OK] = handle_imsg_update_cert_ok,
127 	[IMSG_FILE_OPENED] = handle_imsg_file_opened,
128 };
129 
130 static struct ohash	certs;
131 
132 static void __attribute__((__noreturn__))
133 die(void)
134 {
135 	abort(); 		/* TODO */
136 }
137 
138 static struct tab *
139 tab_by_id_try(uint32_t id)
140 {
141 	struct tab *t;
142 
143 	TAILQ_FOREACH(t, &tabshead, tabs) {
144 		if (t->id == id)
145 			return t;
146 	}
147 
148 	return NULL;
149 }
150 
151 static struct tab *
152 tab_by_id(uint32_t id)
153 {
154 	struct tab *t;
155 
156 	if ((t = tab_by_id_try(id)) == NULL)
157 		die();
158 	return t;
159 }
160 
161 static void
162 handle_imsg_err(struct imsg *imsg, size_t datalen)
163 {
164 	struct tab	*tab;
165 	char		*page;
166 
167 	tab = tab_by_id(imsg->hdr.peerid);
168 
169 	page = imsg->data;
170 	page[datalen-1] = '\0';
171 
172 	if (asprintf(&page, "# Error loading %s\n\n> %s\n",
173 	    tab->hist_cur->h, page) == -1)
174 		die();
175 	load_page_from_str(tab, page);
176 	free(page);
177 }
178 
179 static void
180 handle_imsg_check_cert(struct imsg *imsg, size_t datalen)
181 {
182 	const char		*hash, *host, *port;
183 	int			 tofu_res;
184 	struct tofu_entry	*e;
185 	struct tab		*tab;
186 
187 	hash = imsg->data;
188 	if (hash[datalen-1] != '\0')
189 		abort();
190 
191 	tab = tab_by_id(imsg->hdr.peerid);
192 
193 	if (tab->proxy != NULL) {
194 		host = tab->proxy->host;
195 		port = tab->proxy->port;
196 	} else {
197 		host = tab->uri.host;
198 		port = tab->uri.port;
199 	}
200 
201 	if ((e = tofu_lookup(&certs, host, port)) == NULL) {
202 		/* TODO: an update in libressl/libretls changed
203 		 * significantly.  Find a better approach at storing
204 		 * the certs! */
205 		if (datalen > sizeof(e->hash))
206 			abort();
207 
208 		tofu_res = 1;	/* trust on first use */
209 		if ((e = calloc(1, sizeof(*e))) == NULL)
210 			abort();
211 		strlcpy(e->domain, host, sizeof(e->domain));
212 		if (*port != '\0' && strcmp(port, "1965")) {
213 			strlcat(e->domain, ":", sizeof(e->domain));
214 			strlcat(e->domain, port, sizeof(e->domain));
215 		}
216 		strlcpy(e->hash, hash, sizeof(e->hash));
217 		tofu_add(&certs, e);
218 		ui_send_fs(IMSG_SAVE_CERT, tab->id, e, sizeof(*e));
219 	} else
220 		tofu_res = !strcmp(hash, e->hash);
221 
222 	if (tofu_res) {
223 		if (e->verified == -1)
224 			tab->trust = TS_TEMP_TRUSTED;
225 		else if (e->verified == 1)
226 			tab->trust = TS_VERIFIED;
227 		else
228 			tab->trust = TS_TRUSTED;
229 
230 		ui_send_net(IMSG_CERT_STATUS, imsg->hdr.peerid,
231 		    &tofu_res, sizeof(tofu_res));
232 	} else {
233 		tab->trust = TS_UNTRUSTED;
234 		load_page_from_str(tab, "# Certificate mismatch\n");
235 		if ((tab->cert = strdup(hash)) == NULL)
236 			die();
237 		ui_yornp("Certificate mismatch.  Proceed?",
238 		    handle_check_cert_user_choice, tab);
239 	}
240 }
241 
242 static void
243 handle_check_cert_user_choice(int accept, struct tab *tab)
244 {
245 	ui_send_net(IMSG_CERT_STATUS, tab->id, &accept,
246 	    sizeof(accept));
247 
248 	if (accept) {
249 		/*
250 		 * trust the certificate for this session only.  If
251 		 * the page results in a redirect while we're asking
252 		 * the user to save, we'll end up with an invalid
253 		 * tabid (one request == one tab id) and crash.  It
254 		 * also makes sense to save it for the current session
255 		 * if the user accepted it.
256 		 */
257 		tofu_temp_trust(&certs, tab->uri.host, tab->uri.port, tab->cert);
258 
259 		ui_yornp("Save the new certificate?",
260 		    handle_maybe_save_new_cert, tab);
261 	} else {
262 		free(tab->cert);
263 		tab->cert = NULL;
264 	}
265 }
266 
267 static void
268 handle_maybe_save_new_cert(int accept, struct tab *tab)
269 {
270 	struct tofu_entry *e;
271 	const char *host, *port;
272 
273 	if (tab->proxy != NULL) {
274 		host = tab->proxy->host;
275 		port = tab->proxy->port;
276 	} else {
277 		host = tab->uri.host;
278 		port = tab->uri.port;
279 	}
280 
281 	if (!accept)
282 		goto end;
283 
284 	if ((e = calloc(1, sizeof(*e))) == NULL)
285 		die();
286 
287 	strlcpy(e->domain, host, sizeof(e->domain));
288 	if (*port != '\0' && strcmp(port, "1965")) {
289 		strlcat(e->domain, ":", sizeof(e->domain));
290 		strlcat(e->domain, port, sizeof(e->domain));
291 	}
292 	strlcpy(e->hash, tab->cert, sizeof(e->hash));
293 	ui_send_fs(IMSG_UPDATE_CERT, 0, e, sizeof(*e));
294 
295 	tofu_update(&certs, e);
296 
297 	tab->trust = TS_TRUSTED;
298 
299 end:
300 	free(tab->cert);
301 	tab->cert = NULL;
302 }
303 
304 static inline int
305 normalize_code(int n)
306 {
307 	if (n < 20) {
308 		if (n == 10 || n == 11)
309 			return n;
310 		return 10;
311 	} else if (n < 30) {
312 		return 20;
313 	} else if (n < 40) {
314 		if (n == 30 || n == 31)
315 			return n;
316 		return 30;
317 	} else if (n < 50) {
318 		if (n <= 44)
319 			return n;
320 		return 40;
321 	} else if (n < 60) {
322 		if (n <= 53 || n == 59)
323 			return n;
324 		return 50;
325 	} else if (n < 70) {
326 		if (n <= 62)
327 			return n;
328 		return 60;
329 	} else
330 		return MALFORMED_RESPONSE;
331 }
332 
333 static void
334 handle_imsg_got_code(struct imsg *imsg, size_t datalen)
335 {
336 	struct tab	*tab;
337 
338 	tab = tab_by_id(imsg->hdr.peerid);
339 
340 	if (sizeof(tab->code) != datalen)
341 		die();
342 
343 	memcpy(&tab->code, imsg->data, sizeof(tab->code));
344 	tab->code = normalize_code(tab->code);
345 	if (tab->code != 30 && tab->code != 31)
346 		tab->redirect_count = 0;
347 }
348 
349 static void
350 handle_imsg_got_meta(struct imsg *imsg, size_t datalen)
351 {
352 	struct tab	*tab;
353 
354 	tab = tab_by_id(imsg->hdr.peerid);
355 
356 	if (sizeof(tab->meta) <= datalen)
357 		die();
358 
359 	memcpy(tab->meta, imsg->data, datalen);
360 
361 	if (tab->code < 10) {	/* internal errors */
362 		load_page_from_str(tab, err_pages[tab->code]);
363 	} else if (tab->code < 20) {	/* 1x */
364 		load_page_from_str(tab, err_pages[tab->code]);
365 		ui_require_input(tab, tab->code == 11);
366 	} else if (tab->code == 20) {
367 		if (setup_parser_for(tab)) {
368 			ui_send_net(IMSG_PROCEED, tab->id, NULL, 0);
369 		} else {
370 			load_page_from_str(tab, err_pages[UNKNOWN_TYPE_OR_CSET]);
371 			ui_yornp("Can't display page, wanna save?",
372 			    handle_maybe_save_page, tab);
373 		}
374 	} else if (tab->code < 40) { /* 3x */
375 		tab->redirect_count++;
376 
377 		/* TODO: make customizable? */
378 		if (tab->redirect_count > 5) {
379 			load_page_from_str(tab,
380 			    err_pages[TOO_MUCH_REDIRECTS]);
381 		} else
382 			do_load_url(tab, tab->meta);
383 	} else { /* 4x, 5x & 6x */
384 		load_page_from_str(tab, err_pages[tab->code]);
385 	}
386 }
387 
388 static void
389 handle_maybe_save_page(int dosave, struct tab *tab)
390 {
391 	if (dosave)
392 		ui_read("Save to path", handle_save_page_path, tab);
393 	else
394 		stop_tab(tab);
395 }
396 
397 static void
398 handle_save_page_path(const char *path, struct tab *tab)
399 {
400 	if (path == NULL) {
401 		stop_tab(tab);
402 		return;
403 	}
404 
405 	tab->path = strdup(path);
406 
407 	ui_send_fs(IMSG_FILE_OPEN, tab->id, path, strlen(path)+1);
408 }
409 
410 static void
411 handle_imsg_file_opened(struct imsg *imsg, size_t datalen)
412 {
413 	struct tab	*tab;
414 	char		*page;
415 	const char	*e;
416 	int		 l;
417 
418 	tab = tab_by_id(imsg->hdr.peerid);
419 
420 	if (imsg->fd == -1) {
421 		stop_tab(tab);
422 
423 		e = imsg->data;
424 		if (e[datalen-1] != '\0')
425 			die();
426 		l = asprintf(&page, "# Can't open file\n\n> %s: %s\n",
427 		    tab->path, e);
428 		if (l == -1)
429 			die();
430 		load_page_from_str(tab, page);
431 		free(page);
432 	} else {
433 		tab->fd = imsg->fd;
434 		ui_send_net(IMSG_PROCEED, tab->id, NULL, 0);
435 	}
436 }
437 
438 static void
439 handle_imsg_buf(struct imsg *imsg, size_t datalen)
440 {
441 	struct tab	*tab;
442 	int		 l;
443 	char		*page, buf[FMT_SCALED_STRSIZE] = {0};
444 
445 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL) {
446 		/*
447 		 * Since messages between ui and net are asynchronous,
448 		 * we could be in a case where we sent a tab_stop
449 		 * command, but still receive data for the old id.  My
450 		 * initial idea of crashing on invalid tab ids just
451 		 * doesn't scale well in an asynchronous world.
452 		 */
453 		return;
454 	}
455 
456 	tab->bytes += datalen;
457 	if (tab->fd == -1) {
458 		if (!tab->buffer.page.parse(&tab->buffer.page,
459 		    imsg->data, datalen))
460 			die();
461 	} else {
462 		write(tab->fd, imsg->data, datalen);
463 		fmt_scaled(tab->bytes, buf);
464 		l = asprintf(&page, "Saving to \"%s\"... (%s)\n",
465 		    tab->path,
466 		    buf);
467 		if (l == -1)
468 			die();
469 		load_page_from_str(tab, page);
470 		free(page);
471 	}
472 
473 	ui_on_tab_refresh(tab);
474 }
475 
476 static void
477 handle_imsg_eof(struct imsg *imsg, size_t datalen)
478 {
479 	struct tab	*tab;
480 	int		 l;
481 	char		*page, buf[FMT_SCALED_STRSIZE] = {0};
482 
483 	tab = tab_by_id(imsg->hdr.peerid);
484 
485 	if (tab->fd == -1) {
486 		if (!tab->buffer.page.free(&tab->buffer.page))
487 			die();
488 	} else {
489 		fmt_scaled(tab->bytes, buf);
490 		l = asprintf(&page, "Saved to \"%s\" (%s)\n",
491 		    tab->path,
492 		    buf);
493 		if (l == -1)
494 			die();
495 		load_page_from_str(tab, page);
496 		free(page);
497 
498 		close(tab->fd);
499 		tab->fd = -1;
500 		free(tab->path);
501 		tab->path = NULL;
502 	}
503 
504 	ui_on_tab_refresh(tab);
505 	ui_on_tab_loaded(tab);
506 }
507 
508 static void
509 handle_imsg_bookmark_ok(struct imsg *imsg, size_t datalen)
510 {
511 	int res;
512 
513 	if (datalen != sizeof(res))
514 		die();
515 
516 	memcpy(&res, imsg->data, sizeof(res));
517 	if (res == 0)
518 		message("Added to bookmarks!");
519 	else
520 		message("Failed to add to bookmarks: %s",
521 		    strerror(res));
522 }
523 
524 static void
525 handle_imsg_save_cert_ok(struct imsg *imsg, size_t datalen)
526 {
527 	int res;
528 
529 	if (datalen != sizeof(res))
530 		die();
531 	memcpy(&res, imsg->data, datalen);
532 	if (res != 0)
533 		message("Failed to save the cert for: %s",
534 		    strerror(res));
535 }
536 
537 static void
538 handle_imsg_update_cert_ok(struct imsg *imsg, size_t datalen)
539 {
540 	int res;
541 
542 	if (datalen != sizeof(res))
543 		die();
544 	memcpy(&res, imsg->data, datalen);
545 	if (!res)
546 		message("Failed to update the certificate");
547 }
548 
549 static void
550 handle_dispatch_imsg(int fd, short ev, void *d)
551 {
552 	struct imsgev	*iev = d;
553 	dispatch_imsg(iev, ev, handlers, sizeof(handlers));
554 }
555 
556 static void
557 load_page_from_str(struct tab *tab, const char *page)
558 {
559 	erase_buffer(&tab->buffer);
560 	gemtext_initparser(&tab->buffer.page);
561 	if (!tab->buffer.page.parse(&tab->buffer.page, page, strlen(page)))
562 		die();
563 	if (!tab->buffer.page.free(&tab->buffer.page))
564 		die();
565 	ui_on_tab_refresh(tab);
566 	ui_on_tab_loaded(tab);
567 }
568 
569 void
570 load_about_url(struct tab *tab, const char *url)
571 {
572 	tab->trust = TS_VERIFIED;
573 
574 	gemtext_initparser(&tab->buffer.page);
575 
576 	ui_send_fs(IMSG_GET, tab->id,
577 	    tab->hist_cur->h, strlen(tab->hist_cur->h)+1);
578 }
579 
580 void
581 load_gemini_url(struct tab *tab, const char *url)
582 {
583 	struct get_req	 req;
584 
585 	stop_tab(tab);
586 	tab->id = tab_new_id();
587 
588 	memset(&req, 0, sizeof(req));
589 	strlcpy(req.host, tab->uri.host, sizeof(req.host));
590 	strlcpy(req.port, tab->uri.port, sizeof(req.host));
591 
592 	strlcpy(req.req, tab->hist_cur->h, sizeof(req.req));
593 	strlcat(req.req, "\r\n", sizeof(req.req));
594 
595 	req.proto = PROTO_GEMINI;
596 
597 	ui_send_net(IMSG_GET_RAW, tab->id,
598 	    &req, sizeof(req));
599 }
600 
601 void
602 load_via_proxy(struct tab *tab, const char *url, struct proxy *p)
603 {
604 	struct get_req req;
605 
606 	stop_tab(tab);
607 	tab->id = tab_new_id();
608 	tab->proxy = p;
609 
610 	memset(&req, 0, sizeof(req));
611 	strlcpy(req.host, p->host, sizeof(req.host));
612 	strlcpy(req.port, p->port, sizeof(req.host));
613 
614 	strlcpy(req.req, tab->hist_cur->h, sizeof(req.req));
615 	strlcat(req.req, "\r\n", sizeof(req.req));
616 
617 	req.proto = p->proto;
618 
619 	ui_send_net(IMSG_GET_RAW, tab->id,
620 	    &req, sizeof(req));
621 }
622 
623 /*
624  * Effectively load the given url in the given tab.  Return 1 when
625  * loading the page asynchronously, and thus when an erase_buffer can
626  * be done right after this function return, or 0 when loading the
627  * page synchronously.  In this last case, erase_buffer *MUST* be
628  * called by the handling function (such as load_page_from_str).
629  */
630 static int
631 do_load_url(struct tab *tab, const char *url)
632 {
633 	struct phos_uri	 uri;
634 	struct proto	*p;
635 	struct proxy	*proxy;
636 	char		*t;
637 
638 	tab->proxy = NULL;
639 
640 	if (tab->fd != -1) {
641 		close(tab->fd);
642 		tab->fd = -1;
643 		free(tab->path);
644 		tab->path = NULL;
645 	}
646 
647 	tab->trust = TS_UNKNOWN;
648 
649 	memcpy(&uri, &tab->uri, sizeof(tab->uri));
650 	if (!phos_resolve_uri_from_str(&uri, url, &tab->uri)) {
651                 if (asprintf(&t, "#error loading %s\n>%s\n",
652 		    url, "Can't parse the URI") == -1)
653 			die();
654 		strlcpy(tab->hist_cur->h, url, sizeof(tab->hist_cur->h));
655 		load_page_from_str(tab, t);
656 		free(t);
657 		return 0;
658 	}
659 
660 	phos_serialize_uri(&tab->uri, tab->hist_cur->h,
661 	    sizeof(tab->hist_cur->h));
662 
663 	for (p = protos; p->schema != NULL; ++p) {
664 		if (!strcmp(tab->uri.scheme, p->schema)) {
665 			p->loadfn(tab, url);
666                         return 1;
667 		}
668 	}
669 
670 	TAILQ_FOREACH(proxy, &proxies, proxies) {
671 		if (!strcmp(tab->uri.scheme, proxy->match_proto)) {
672 			load_via_proxy(tab, url, proxy);
673 			return 1;
674 		}
675 	}
676 
677 	load_page_from_str(tab, err_pages[UNKNOWN_PROTOCOL]);
678 	return 0;
679 }
680 
681 /*
682  * Load url in tab.  If tab is marked as lazy, only prepare the url
683  * but don't load it.  If tab is lazy and a url was already prepared,
684  * do load it!
685  */
686 void
687 load_url(struct tab *tab, const char *url)
688 {
689 	int lazy;
690 
691 	lazy = tab->flags & TAB_LAZY;
692 
693 	if (lazy && tab->hist_cur != NULL) {
694 		lazy = 0;
695 		tab->flags &= ~TAB_LAZY;
696 	}
697 
698 	if (!lazy || tab->hist_cur == NULL) {
699 		if (tab->hist_cur != NULL)
700 			hist_clear_forward(&tab->hist,
701 			    TAILQ_NEXT(tab->hist_cur, entries));
702 
703 		if ((tab->hist_cur = calloc(1, sizeof(*tab->hist_cur))) == NULL) {
704 			event_loopbreak();
705 			return;
706 		}
707 
708 		strlcpy(tab->buffer.page.title, url,
709 		    sizeof(tab->buffer.page.title));
710 		hist_push(&tab->hist, tab->hist_cur);
711 
712 		if (lazy)
713 			strlcpy(tab->hist_cur->h, url,
714 			    sizeof(tab->hist_cur->h));
715 	}
716 
717 	if (!lazy && do_load_url(tab, url))
718 		erase_buffer(&tab->buffer);
719 }
720 
721 int
722 load_previous_page(struct tab *tab)
723 {
724 	struct hist	*h;
725 
726 	if ((h = TAILQ_PREV(tab->hist_cur, mhisthead, entries)) == NULL)
727 		return 0;
728 	tab->hist_cur = h;
729 	do_load_url(tab, h->h);
730 	return 1;
731 }
732 
733 int
734 load_next_page(struct tab *tab)
735 {
736 	struct hist	*h;
737 
738 	if ((h = TAILQ_NEXT(tab->hist_cur, entries)) == NULL)
739 		return 0;
740 	tab->hist_cur = h;
741 	do_load_url(tab, h->h);
742 	return 1;
743 }
744 
745 void
746 stop_tab(struct tab *tab)
747 {
748 	ui_send_net(IMSG_STOP, tab->id, NULL, 0);
749 
750 	if (tab->fd != -1) {
751 		close(tab->fd);
752 		tab->fd = -1;
753 		free(tab->path);
754 		tab->path = NULL;
755 		load_page_from_str(tab, "Stopped.\n");
756 	}
757 }
758 
759 void
760 add_to_bookmarks(const char *str)
761 {
762 	ui_send_fs(IMSG_BOOKMARK_PAGE, 0,
763 	    str, strlen(str)+1);
764 }
765 
766 void
767 save_session(void)
768 {
769 	struct tab	*tab;
770 	char		*t;
771 	int		 flags;
772 
773 	ui_send_fs(IMSG_SESSION_START, 0, NULL, 0);
774 
775 	TAILQ_FOREACH(tab, &tabshead, tabs) {
776 		flags = tab->flags;
777 		if (tab == current_tab)
778 			flags |= TAB_CURRENT;
779 
780 		t = tab->hist_cur->h;
781 		ui_send_fs(IMSG_SESSION_TAB, flags, t, strlen(t)+1);
782 
783 		t = tab->buffer.page.title;
784 		ui_send_fs(IMSG_SESSION_TAB_TITLE, 0, t, strlen(t)+1);
785 	}
786 
787 	ui_send_fs(IMSG_SESSION_END, 0, NULL, 0);
788 }
789 
790 /*
791  * Parse a line of the session file.  The format is:
792  *
793  *	URL [flags,...] [title]\n
794  */
795 static void
796 parse_session_line(char *line, const char **title, uint32_t *flags)
797 {
798 	char *s, *t, *ap;
799 
800 	*title = "";
801 	*flags = 0;
802 	if ((s = strchr(line, ' ')) == NULL)
803 		return;
804 
805 	*s++ = '\0';
806 
807         if ((t = strchr(s, ' ')) != NULL) {
808 		*t++ = '\0';
809 		*title = t;
810 	}
811 
812 	while ((ap = strsep(&s, ",")) != NULL) {
813 		if (*ap == '\0')
814 			;
815 		else if (!strcmp(ap, "current"))
816 			*flags |= TAB_CURRENT;
817 		else
818 			message("unknown tab flag: %s", ap);
819 	}
820 }
821 
822 static void
823 load_last_session(void)
824 {
825 	const char	*title;
826 	char		*nl, *line = NULL;
827 	uint32_t	 flags;
828 	size_t		 linesize = 0;
829 	ssize_t		 linelen;
830 	FILE		*session;
831 	struct tab	*tab, *curr = NULL;
832 
833 	if ((session = fopen(session_file, "r")) == NULL) {
834 		/* first time? */
835 		new_tab("about:new");
836 		switch_to_tab(new_tab("about:help"));
837 		return;
838 	}
839 
840 	while ((linelen = getline(&line, &linesize, session)) != -1) {
841                 if ((nl = strchr(line, '\n')) != NULL)
842 			*nl = '\0';
843 		parse_session_line(line, &title, &flags);
844 		if ((tab = new_tab(line)) == NULL)
845 			err(1, "new_tab");
846                 strlcpy(tab->buffer.page.title, title,
847 		    sizeof(tab->buffer.page.title));
848 		if (flags & TAB_CURRENT)
849 			curr = tab;
850 	}
851 
852 	if (ferror(session))
853 		message("error reading %s: %s",
854 		    session_file, strerror(errno));
855 	fclose(session);
856 	free(line);
857 
858 	if (curr != NULL)
859 		switch_to_tab(curr);
860 
861 	return;
862 }
863 
864 static pid_t
865 start_child(enum telescope_process p, const char *argv0, int fd)
866 {
867 	const char	*argv[4];
868 	int		 argc = 0;
869 	pid_t		 pid;
870 
871 	switch (pid = fork()) {
872 	case -1:
873 		die();
874 	case 0:
875 		break;
876 	default:
877 		close(fd);
878 		return pid;
879 	}
880 
881 	if (dup2(fd, 3) == -1)
882 		err(1, "cannot setup imsg fd");
883 
884 	argv[argc++] = argv0;
885 	switch (p) {
886 	case PROC_UI:
887 		errx(1, "Can't start ui process");
888 	case PROC_FS:
889 		argv[argc++] = "-Tf";
890 		break;
891 	case PROC_NET:
892 		argv[argc++] = "-Tn";
893 		break;
894 	}
895 
896 	argv[argc++] = NULL;
897 	execvp(argv0, (char *const *)argv);
898 	err(1, "execvp(%s)", argv0);
899 }
900 
901 static int
902 ui_send_net(int type, uint32_t peerid, const void *data,
903     uint16_t datalen)
904 {
905 	return imsg_compose_event(iev_net, type, peerid, 0, -1, data,
906 	    datalen);
907 }
908 
909 static int
910 ui_send_fs(int type, uint32_t peerid, const void *data, uint16_t datalen)
911 {
912 	return imsg_compose_event(iev_fs, type, peerid, 0, -1, data,
913 	    datalen);
914 }
915 
916 static void __attribute__((noreturn))
917 usage(int r)
918 {
919 	fprintf(stderr, "USAGE: %s [-hnv] [-c config] [url]\n",
920 	    getprogname());
921 	fprintf(stderr, "version: " PACKAGE " " VERSION "\n");
922 	exit(r);
923 }
924 
925 int
926 main(int argc, char * const *argv)
927 {
928 	struct imsgev	 net_ibuf, fs_ibuf;
929 	int		 pipe2net[2], pipe2fs[2];
930 	int		 ch, configtest = 0, fail = 0;
931 	int		 has_url = 0;
932 	int		 proc = -1;
933 	int		 sessionfd;
934 	char		 path[PATH_MAX];
935 	const char	*url = NEW_TAB_URL;
936 	const char	*argv0;
937 
938 	argv0 = argv[0];
939 
940 	signal(SIGCHLD, SIG_IGN);
941 	signal(SIGPIPE, SIG_IGN);
942 
943 	if (getenv("NO_COLOR") != NULL)
944 		enable_colors = 0;
945 
946 	strlcpy(path, getenv("HOME"), sizeof(path));
947 	strlcat(path, "/.telescope/config", sizeof(path));
948 
949 	while ((ch = getopt_long(argc, argv, opts, longopts, NULL)) != -1) {
950 		switch (ch) {
951 		case 'C':
952 			exit(ui_print_colors());
953 		case 'c':
954 			fail = 1;
955 			strlcpy(path, optarg, sizeof(path));
956 			break;
957 		case 'n':
958 			configtest = 1;
959 			break;
960 		case 'h':
961 			usage(0);
962 		case 'T':
963 			switch (*optarg) {
964 			case 'f':
965 				proc = PROC_FS;
966 				break;
967 			case 'n':
968 				proc = PROC_NET;
969 				break;
970 			default:
971 				errx(1, "invalid process spec %c",
972 				    *optarg);
973 			}
974 			break;
975 		case 'v':
976 			printf("%s %s\n", PACKAGE_NAME, PACKAGE_VERSION);
977 			exit(0);
978 			break;
979 		default:
980 			usage(1);
981 		}
982 	}
983 
984 	argc -= optind;
985 	argv += optind;
986 
987 	if (proc != -1) {
988 		if (argc > 0)
989 			usage(1);
990 		else if (proc == PROC_FS)
991 			return fs_main();
992 		else if (proc == PROC_NET)
993 			return client_main();
994 		else
995 			usage(1);
996 	}
997 
998 	if (argc != 0) {
999 		has_url = 1;
1000 		url = argv[0];
1001 	}
1002 
1003 	/* setup keys before reading the config */
1004 	TAILQ_INIT(&global_map.m);
1005 	global_map.unhandled_input = global_key_unbound;
1006 	TAILQ_INIT(&minibuffer_map.m);
1007 
1008 	config_init();
1009 	parseconfig(path, fail);
1010 	if (configtest){
1011 		puts("config OK");
1012 		exit(0);
1013 	}
1014 
1015 	fs_init();
1016 	if ((sessionfd = lock_session()) == -1)
1017 		errx(1, "can't lock session, is another instance of "
1018 		    "telescope already running?");
1019 
1020 	/* Start children. */
1021 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pipe2fs) == -1)
1022 		err(1, "socketpair");
1023 	start_child(PROC_FS, argv0, pipe2fs[1]);
1024 	imsg_init(&fs_ibuf.ibuf, pipe2fs[0]);
1025 	iev_fs = &fs_ibuf;
1026 	iev_fs->handler = handle_dispatch_imsg;
1027 
1028 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pipe2net) == -1)
1029 		err(1, "socketpair");
1030 	start_child(PROC_NET, argv0, pipe2net[1]);
1031 	imsg_init(&net_ibuf.ibuf, pipe2net[0]);
1032 	iev_net = &net_ibuf;
1033 	iev_net->handler = handle_dispatch_imsg;
1034 
1035 	setproctitle("ui");
1036 
1037 	/* initialize tofu & load certificates */
1038 	tofu_init(&certs, 5, offsetof(struct tofu_entry, domain));
1039 	load_certs(&certs);
1040 
1041 	event_init();
1042 
1043 	/* Setup event handlers for pipes to fs/net */
1044 	iev_fs->events = EV_READ;
1045 	event_set(&iev_fs->ev, iev_fs->ibuf.fd, iev_fs->events,
1046 	    iev_fs->handler, iev_fs);
1047 	event_add(&iev_fs->ev, NULL);
1048 
1049 	iev_net->events = EV_READ;
1050 	event_set(&iev_net->ev, iev_net->ibuf.fd, iev_net->events,
1051 	    iev_net->handler, iev_net);
1052 	event_add(&iev_net->ev, NULL);
1053 
1054 	if (ui_init()) {
1055 		load_last_session();
1056 		if (has_url || TAILQ_EMPTY(&tabshead))
1057 			new_tab(url);
1058 
1059 		sandbox_ui_process();
1060 		ui_main_loop();
1061 		ui_end();
1062 	}
1063 
1064 	ui_send_fs(IMSG_QUIT, 0, NULL, 0);
1065 	ui_send_net(IMSG_QUIT, 0, NULL, 0);
1066 	imsg_flush(&iev_fs->ibuf);
1067 	imsg_flush(&iev_net->ibuf);
1068 
1069 	close(sessionfd);
1070 
1071 	return 0;
1072 }