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Date:: Sun Jul 18 15:58:37 2021 UTC
Message:: added missing copyright header
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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(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 	die();
149 }
150 
151 static void
152 handle_imsg_err(struct imsg *imsg, size_t datalen)
153 {
154 	struct tab	*tab;
155 	char		*page;
156 
157 	tab = tab_by_id(imsg->hdr.peerid);
158 
159 	page = imsg->data;
160 	page[datalen-1] = '\0';
161 
162 	if (asprintf(&page, "# Error loading %s\n\n> %s\n",
163 	    tab->hist_cur->h, page) == -1)
164 		die();
165 	load_page_from_str(tab, page);
166 	free(page);
167 }
168 
169 static void
170 handle_imsg_check_cert(struct imsg *imsg, size_t datalen)
171 {
172 	const char		*hash, *host, *port;
173 	int			 tofu_res;
174 	struct tofu_entry	*e;
175 	struct tab		*tab;
176 
177 	hash = imsg->data;
178 	if (hash[datalen-1] != '\0')
179 		abort();
180 
181 	tab = tab_by_id(imsg->hdr.peerid);
182 
183 	if (tab->proxy != NULL) {
184 		host = tab->proxy->host;
185 		port = tab->proxy->port;
186 	} else {
187 		host = tab->uri.host;
188 		port = tab->uri.port;
189 	}
190 
191 	if ((e = tofu_lookup(&certs, host, port)) == NULL) {
192 		/* TODO: an update in libressl/libretls changed
193 		 * significantly.  Find a better approach at storing
194 		 * the certs! */
195 		if (datalen > sizeof(e->hash))
196 			abort();
197 
198 		tofu_res = 1;	/* trust on first use */
199 		if ((e = calloc(1, sizeof(*e))) == NULL)
200 			abort();
201 		strlcpy(e->domain, host, sizeof(e->domain));
202 		if (*port != '\0' && strcmp(port, "1965")) {
203 			strlcat(e->domain, ":", sizeof(e->domain));
204 			strlcat(e->domain, port, sizeof(e->domain));
205 		}
206 		strlcpy(e->hash, hash, sizeof(e->hash));
207 		tofu_add(&certs, e);
208 		ui_send_fs(IMSG_SAVE_CERT, tab->id, e, sizeof(*e));
209 	} else
210 		tofu_res = !strcmp(hash, e->hash);
211 
212 	if (tofu_res) {
213 		if (e->verified == -1)
214 			tab->trust = TS_TEMP_TRUSTED;
215 		else if (e->verified == 1)
216 			tab->trust = TS_VERIFIED;
217 		else
218 			tab->trust = TS_TRUSTED;
219 
220 		ui_send_net(IMSG_CERT_STATUS, imsg->hdr.peerid,
221 		    &tofu_res, sizeof(tofu_res));
222 	} else {
223 		tab->trust = TS_UNTRUSTED;
224 		load_page_from_str(tab, "# Certificate mismatch\n");
225 		if ((tab->cert = strdup(hash)) == NULL)
226 			die();
227 		ui_yornp("Certificate mismatch.  Proceed?",
228 		    handle_check_cert_user_choice, tab);
229 	}
230 }
231 
232 static void
233 handle_check_cert_user_choice(int accept, struct tab *tab)
234 {
235 	ui_send_net(IMSG_CERT_STATUS, tab->id, &accept,
236 	    sizeof(accept));
237 
238 	if (accept) {
239 		/*
240 		 * trust the certificate for this session only.  If
241 		 * the page results in a redirect while we're asking
242 		 * the user to save, we'll end up with an invalid
243 		 * tabid (one request == one tab id) and crash.  It
244 		 * also makes sense to save it for the current session
245 		 * if the user accepted it.
246 		 */
247 		tofu_temp_trust(&certs, tab->uri.host, tab->uri.port, tab->cert);
248 
249 		ui_yornp("Save the new certificate?",
250 		    handle_maybe_save_new_cert, tab);
251 	} else {
252 		free(tab->cert);
253 		tab->cert = NULL;
254 	}
255 }
256 
257 static void
258 handle_maybe_save_new_cert(int accept, struct tab *tab)
259 {
260 	struct tofu_entry *e;
261 	const char *host, *port;
262 
263 	if (tab->proxy != NULL) {
264 		host = tab->proxy->host;
265 		port = tab->proxy->port;
266 	} else {
267 		host = tab->uri.host;
268 		port = tab->uri.port;
269 	}
270 
271 	if (!accept)
272 		goto end;
273 
274 	if ((e = calloc(1, sizeof(*e))) == NULL)
275 		die();
276 
277 	strlcpy(e->domain, host, sizeof(e->domain));
278 	if (*port != '\0' && strcmp(port, "1965")) {
279 		strlcat(e->domain, ":", sizeof(e->domain));
280 		strlcat(e->domain, port, sizeof(e->domain));
281 	}
282 	strlcpy(e->hash, tab->cert, sizeof(e->hash));
283 	ui_send_fs(IMSG_UPDATE_CERT, 0, e, sizeof(*e));
284 
285 	tofu_update(&certs, e);
286 
287 	tab->trust = TS_TRUSTED;
288 
289 end:
290 	free(tab->cert);
291 	tab->cert = NULL;
292 }
293 
294 static inline int
295 normalize_code(int n)
296 {
297 	if (n < 20) {
298 		if (n == 10 || n == 11)
299 			return n;
300 		return 10;
301 	} else if (n < 30) {
302 		return 20;
303 	} else if (n < 40) {
304 		if (n == 30 || n == 31)
305 			return n;
306 		return 30;
307 	} else if (n < 50) {
308 		if (n <= 44)
309 			return n;
310 		return 40;
311 	} else if (n < 60) {
312 		if (n <= 53 || n == 59)
313 			return n;
314 		return 50;
315 	} else if (n < 70) {
316 		if (n <= 62)
317 			return n;
318 		return 60;
319 	} else
320 		return MALFORMED_RESPONSE;
321 }
322 
323 static void
324 handle_imsg_got_code(struct imsg *imsg, size_t datalen)
325 {
326 	struct tab	*tab;
327 
328 	tab = tab_by_id(imsg->hdr.peerid);
329 
330 	if (sizeof(tab->code) != datalen)
331 		die();
332 
333 	memcpy(&tab->code, imsg->data, sizeof(tab->code));
334 	tab->code = normalize_code(tab->code);
335 	if (tab->code != 30 && tab->code != 31)
336 		tab->redirect_count = 0;
337 }
338 
339 static void
340 handle_imsg_got_meta(struct imsg *imsg, size_t datalen)
341 {
342 	struct tab	*tab;
343 
344 	tab = tab_by_id(imsg->hdr.peerid);
345 
346 	if (sizeof(tab->meta) <= datalen)
347 		die();
348 
349 	memcpy(tab->meta, imsg->data, datalen);
350 
351 	if (tab->code < 10) {	/* internal errors */
352 		load_page_from_str(tab, err_pages[tab->code]);
353 	} else if (tab->code < 20) {	/* 1x */
354 		load_page_from_str(tab, err_pages[tab->code]);
355 		ui_require_input(tab, tab->code == 11);
356 	} else if (tab->code == 20) {
357 		if (setup_parser_for(tab)) {
358 			ui_send_net(IMSG_PROCEED, tab->id, NULL, 0);
359 		} else {
360 			load_page_from_str(tab, err_pages[UNKNOWN_TYPE_OR_CSET]);
361 			ui_yornp("Can't display page, wanna save?",
362 			    handle_maybe_save_page, tab);
363 		}
364 	} else if (tab->code < 40) { /* 3x */
365 		tab->redirect_count++;
366 
367 		/* TODO: make customizable? */
368 		if (tab->redirect_count > 5) {
369 			load_page_from_str(tab,
370 			    err_pages[TOO_MUCH_REDIRECTS]);
371 		} else
372 			do_load_url(tab, tab->meta);
373 	} else { /* 4x, 5x & 6x */
374 		load_page_from_str(tab, err_pages[tab->code]);
375 	}
376 }
377 
378 static void
379 handle_maybe_save_page(int dosave, struct tab *tab)
380 {
381 	if (dosave)
382 		ui_read("Save to path", handle_save_page_path, tab);
383 	else
384 		stop_tab(tab);
385 }
386 
387 static void
388 handle_save_page_path(const char *path, struct tab *tab)
389 {
390 	if (path == NULL) {
391 		stop_tab(tab);
392 		return;
393 	}
394 
395 	tab->path = strdup(path);
396 
397 	ui_send_fs(IMSG_FILE_OPEN, tab->id, path, strlen(path)+1);
398 }
399 
400 static void
401 handle_imsg_file_opened(struct imsg *imsg, size_t datalen)
402 {
403 	struct tab	*tab;
404 	char		*page;
405 	const char	*e;
406 	int		 l;
407 
408 	tab = tab_by_id(imsg->hdr.peerid);
409 
410 	if (imsg->fd == -1) {
411 		stop_tab(tab);
412 
413 		e = imsg->data;
414 		if (e[datalen-1] != '\0')
415 			die();
416 		l = asprintf(&page, "# Can't open file\n\n> %s: %s\n",
417 		    tab->path, e);
418 		if (l == -1)
419 			die();
420 		load_page_from_str(tab, page);
421 		free(page);
422 	} else {
423 		tab->fd = imsg->fd;
424 		ui_send_net(IMSG_PROCEED, tab->id, NULL, 0);
425 	}
426 }
427 
428 static void
429 handle_imsg_buf(struct imsg *imsg, size_t datalen)
430 {
431 	struct tab	*tab;
432 	int		 l;
433 	char		*page, buf[FMT_SCALED_STRSIZE] = {0};
434 
435 	tab = tab_by_id(imsg->hdr.peerid);
436 
437 	tab->bytes += datalen;
438 	if (tab->fd == -1) {
439 		if (!tab->buffer.page.parse(&tab->buffer.page,
440 		    imsg->data, datalen))
441 			die();
442 	} else {
443 		write(tab->fd, imsg->data, datalen);
444 		fmt_scaled(tab->bytes, buf);
445 		l = asprintf(&page, "Saving to \"%s\"... (%s)\n",
446 		    tab->path,
447 		    buf);
448 		if (l == -1)
449 			die();
450 		load_page_from_str(tab, page);
451 		free(page);
452 	}
453 
454 	ui_on_tab_refresh(tab);
455 }
456 
457 static void
458 handle_imsg_eof(struct imsg *imsg, size_t datalen)
459 {
460 	struct tab	*tab;
461 	int		 l;
462 	char		*page, buf[FMT_SCALED_STRSIZE] = {0};
463 
464 	tab = tab_by_id(imsg->hdr.peerid);
465 
466 	if (tab->fd == -1) {
467 		if (!tab->buffer.page.free(&tab->buffer.page))
468 			die();
469 	} else {
470 		fmt_scaled(tab->bytes, buf);
471 		l = asprintf(&page, "Saved to \"%s\" (%s)\n",
472 		    tab->path,
473 		    buf);
474 		if (l == -1)
475 			die();
476 		load_page_from_str(tab, page);
477 		free(page);
478 
479 		close(tab->fd);
480 		tab->fd = -1;
481 		free(tab->path);
482 		tab->path = NULL;
483 	}
484 
485 	ui_on_tab_refresh(tab);
486 	ui_on_tab_loaded(tab);
487 }
488 
489 static void
490 handle_imsg_bookmark_ok(struct imsg *imsg, size_t datalen)
491 {
492 	int res;
493 
494 	if (datalen != sizeof(res))
495 		die();
496 
497 	memcpy(&res, imsg->data, sizeof(res));
498 	if (res == 0)
499 		message("Added to bookmarks!");
500 	else
501 		message("Failed to add to bookmarks: %s",
502 		    strerror(res));
503 }
504 
505 static void
506 handle_imsg_save_cert_ok(struct imsg *imsg, size_t datalen)
507 {
508 	int res;
509 
510 	if (datalen != sizeof(res))
511 		die();
512 	memcpy(&res, imsg->data, datalen);
513 	if (res != 0)
514 		message("Failed to save the cert for: %s",
515 		    strerror(res));
516 }
517 
518 static void
519 handle_imsg_update_cert_ok(struct imsg *imsg, size_t datalen)
520 {
521 	int res;
522 
523 	if (datalen != sizeof(res))
524 		die();
525 	memcpy(&res, imsg->data, datalen);
526 	if (!res)
527 		message("Failed to update the certificate");
528 }
529 
530 static void
531 handle_dispatch_imsg(int fd, short ev, void *d)
532 {
533 	struct imsgev	*iev = d;
534 	dispatch_imsg(iev, ev, handlers, sizeof(handlers));
535 }
536 
537 static void
538 load_page_from_str(struct tab *tab, const char *page)
539 {
540 	erase_buffer(&tab->buffer);
541 	gemtext_initparser(&tab->buffer.page);
542 	if (!tab->buffer.page.parse(&tab->buffer.page, page, strlen(page)))
543 		die();
544 	if (!tab->buffer.page.free(&tab->buffer.page))
545 		die();
546 	ui_on_tab_refresh(tab);
547 	ui_on_tab_loaded(tab);
548 }
549 
550 void
551 load_about_url(struct tab *tab, const char *url)
552 {
553 	tab->trust = TS_VERIFIED;
554 
555 	gemtext_initparser(&tab->buffer.page);
556 
557 	ui_send_fs(IMSG_GET, tab->id,
558 	    tab->hist_cur->h, strlen(tab->hist_cur->h)+1);
559 }
560 
561 void
562 load_gemini_url(struct tab *tab, const char *url)
563 {
564 	struct get_req	 req;
565 
566 	stop_tab(tab);
567 	tab->id = tab_new_id();
568 
569 	memset(&req, 0, sizeof(req));
570 	strlcpy(req.host, tab->uri.host, sizeof(req.host));
571 	strlcpy(req.port, tab->uri.port, sizeof(req.host));
572 
573 	strlcpy(req.req, tab->hist_cur->h, sizeof(req.req));
574 	strlcat(req.req, "\r\n", sizeof(req.req));
575 
576 	req.proto = PROTO_GEMINI;
577 
578 	ui_send_net(IMSG_GET_RAW, tab->id,
579 	    &req, sizeof(req));
580 }
581 
582 void
583 load_via_proxy(struct tab *tab, const char *url, struct proxy *p)
584 {
585 	struct get_req req;
586 
587 	stop_tab(tab);
588 	tab->id = tab_new_id();
589 	tab->proxy = p;
590 
591 	memset(&req, 0, sizeof(req));
592 	strlcpy(req.host, p->host, sizeof(req.host));
593 	strlcpy(req.port, p->port, sizeof(req.host));
594 
595 	strlcpy(req.req, tab->hist_cur->h, sizeof(req.req));
596 	strlcat(req.req, "\r\n", sizeof(req.req));
597 
598 	req.proto = p->proto;
599 
600 	ui_send_net(IMSG_GET_RAW, tab->id,
601 	    &req, sizeof(req));
602 }
603 
604 /*
605  * Effectively load the given url in the given tab.  Return 1 when
606  * loading the page asynchronously, and thus when an erase_buffer can
607  * be done right after this function return, or 0 when loading the
608  * page synchronously.  In this last case, erase_buffer *MUST* be
609  * called by the handling function (such as load_page_from_str).
610  */
611 static int
612 do_load_url(struct tab *tab, const char *url)
613 {
614 	struct phos_uri	 uri;
615 	struct proto	*p;
616 	struct proxy	*proxy;
617 	char		*t;
618 
619 	tab->proxy = NULL;
620 
621 	if (tab->fd != -1) {
622 		close(tab->fd);
623 		tab->fd = -1;
624 		free(tab->path);
625 		tab->path = NULL;
626 	}
627 
628 	tab->trust = TS_UNKNOWN;
629 
630 	memcpy(&uri, &tab->uri, sizeof(tab->uri));
631 	if (!phos_resolve_uri_from_str(&uri, url, &tab->uri)) {
632                 if (asprintf(&t, "#error loading %s\n>%s\n",
633 		    url, "Can't parse the URI") == -1)
634 			die();
635 		strlcpy(tab->hist_cur->h, url, sizeof(tab->hist_cur->h));
636 		load_page_from_str(tab, t);
637 		free(t);
638 		return 0;
639 	}
640 
641 	phos_serialize_uri(&tab->uri, tab->hist_cur->h,
642 	    sizeof(tab->hist_cur->h));
643 
644 	for (p = protos; p->schema != NULL; ++p) {
645 		if (!strcmp(tab->uri.scheme, p->schema)) {
646 			p->loadfn(tab, url);
647                         return 1;
648 		}
649 	}
650 
651 	TAILQ_FOREACH(proxy, &proxies, proxies) {
652 		if (!strcmp(tab->uri.scheme, proxy->match_proto)) {
653 			load_via_proxy(tab, url, proxy);
654 			return 1;
655 		}
656 	}
657 
658 	load_page_from_str(tab, err_pages[UNKNOWN_PROTOCOL]);
659 	return 0;
660 }
661 
662 /*
663  * Load url in tab.  If tab is marked as lazy, only prepare the url
664  * but don't load it.  If tab is lazy and a url was already prepared,
665  * do load it!
666  */
667 void
668 load_url(struct tab *tab, const char *url)
669 {
670 	int lazy;
671 
672 	lazy = tab->flags & TAB_LAZY;
673 
674 	if (lazy && tab->hist_cur != NULL) {
675 		lazy = 0;
676 		tab->flags &= ~TAB_LAZY;
677 	}
678 
679 	if (!lazy || tab->hist_cur == NULL) {
680 		if (tab->hist_cur != NULL)
681 			hist_clear_forward(&tab->hist,
682 			    TAILQ_NEXT(tab->hist_cur, entries));
683 
684 		if ((tab->hist_cur = calloc(1, sizeof(*tab->hist_cur))) == NULL) {
685 			event_loopbreak();
686 			return;
687 		}
688 
689 		strlcpy(tab->buffer.page.title, url,
690 		    sizeof(tab->buffer.page.title));
691 		hist_push(&tab->hist, tab->hist_cur);
692 
693 		if (lazy)
694 			strlcpy(tab->hist_cur->h, url,
695 			    sizeof(tab->hist_cur->h));
696 	}
697 
698 	if (!lazy && do_load_url(tab, url))
699 		erase_buffer(&tab->buffer);
700 }
701 
702 int
703 load_previous_page(struct tab *tab)
704 {
705 	struct hist	*h;
706 
707 	if ((h = TAILQ_PREV(tab->hist_cur, mhisthead, entries)) == NULL)
708 		return 0;
709 	tab->hist_cur = h;
710 	do_load_url(tab, h->h);
711 	return 1;
712 }
713 
714 int
715 load_next_page(struct tab *tab)
716 {
717 	struct hist	*h;
718 
719 	if ((h = TAILQ_NEXT(tab->hist_cur, entries)) == NULL)
720 		return 0;
721 	tab->hist_cur = h;
722 	do_load_url(tab, h->h);
723 	return 1;
724 }
725 
726 void
727 stop_tab(struct tab *tab)
728 {
729 	ui_send_net(IMSG_STOP, tab->id, NULL, 0);
730 
731 	if (tab->fd != -1) {
732 		close(tab->fd);
733 		tab->fd = -1;
734 		free(tab->path);
735 		tab->path = NULL;
736 		load_page_from_str(tab, "Stopped.\n");
737 	}
738 }
739 
740 void
741 add_to_bookmarks(const char *str)
742 {
743 	ui_send_fs(IMSG_BOOKMARK_PAGE, 0,
744 	    str, strlen(str)+1);
745 }
746 
747 void
748 save_session(void)
749 {
750 	struct tab	*tab;
751 	char		*t;
752 	int		 flags;
753 
754 	ui_send_fs(IMSG_SESSION_START, 0, NULL, 0);
755 
756 	TAILQ_FOREACH(tab, &tabshead, tabs) {
757 		flags = tab->flags;
758 		if (tab == current_tab)
759 			flags |= TAB_CURRENT;
760 
761 		t = tab->hist_cur->h;
762 		ui_send_fs(IMSG_SESSION_TAB, flags, t, strlen(t)+1);
763 
764 		t = tab->buffer.page.title;
765 		ui_send_fs(IMSG_SESSION_TAB_TITLE, 0, t, strlen(t)+1);
766 	}
767 
768 	ui_send_fs(IMSG_SESSION_END, 0, NULL, 0);
769 }
770 
771 /*
772  * Parse a line of the session file.  The format is:
773  *
774  *	URL [flags,...] [title]\n
775  */
776 static void
777 parse_session_line(char *line, const char **title, uint32_t *flags)
778 {
779 	char *s, *t, *ap;
780 
781 	*title = "";
782 	*flags = 0;
783 	if ((s = strchr(line, ' ')) == NULL)
784 		return;
785 
786 	*s++ = '\0';
787 
788         if ((t = strchr(s, ' ')) != NULL) {
789 		*t++ = '\0';
790 		*title = t;
791 	}
792 
793 	while ((ap = strsep(&s, ",")) != NULL) {
794 		if (*ap == '\0')
795 			;
796 		else if (!strcmp(ap, "current"))
797 			*flags |= TAB_CURRENT;
798 		else
799 			message("unknown tab flag: %s", ap);
800 	}
801 }
802 
803 static void
804 load_last_session(void)
805 {
806 	const char	*title;
807 	char		*nl, *line = NULL;
808 	uint32_t	 flags;
809 	size_t		 linesize = 0;
810 	ssize_t		 linelen;
811 	FILE		*session;
812 	struct tab	*tab, *curr = NULL;
813 
814 	if ((session = fopen(session_file, "r")) == NULL) {
815 		/* first time? */
816 		new_tab("about:new");
817 		switch_to_tab(new_tab("about:help"));
818 		return;
819 	}
820 
821 	while ((linelen = getline(&line, &linesize, session)) != -1) {
822                 if ((nl = strchr(line, '\n')) != NULL)
823 			*nl = '\0';
824 		parse_session_line(line, &title, &flags);
825 		if ((tab = new_tab(line)) == NULL)
826 			err(1, "new_tab");
827                 strlcpy(tab->buffer.page.title, title,
828 		    sizeof(tab->buffer.page.title));
829 		if (flags & TAB_CURRENT)
830 			curr = tab;
831 	}
832 
833 	if (ferror(session))
834 		message("error reading %s: %s",
835 		    session_file, strerror(errno));
836 	fclose(session);
837 	free(line);
838 
839 	if (curr != NULL)
840 		switch_to_tab(curr);
841 
842 	return;
843 }
844 
845 static pid_t
846 start_child(enum telescope_process p, const char *argv0, int fd)
847 {
848 	const char	*argv[4];
849 	int		 argc = 0;
850 	pid_t		 pid;
851 
852 	switch (pid = fork()) {
853 	case -1:
854 		die();
855 	case 0:
856 		break;
857 	default:
858 		close(fd);
859 		return pid;
860 	}
861 
862 	if (dup2(fd, 3) == -1)
863 		err(1, "cannot setup imsg fd");
864 
865 	argv[argc++] = argv0;
866 	switch (p) {
867 	case PROC_UI:
868 		errx(1, "Can't start ui process");
869 	case PROC_FS:
870 		argv[argc++] = "-Tf";
871 		break;
872 	case PROC_NET:
873 		argv[argc++] = "-Tn";
874 		break;
875 	}
876 
877 	argv[argc++] = NULL;
878 	execvp(argv0, (char *const *)argv);
879 	err(1, "execvp(%s)", argv0);
880 }
881 
882 static int
883 ui_send_net(int type, uint32_t peerid, const void *data,
884     uint16_t datalen)
885 {
886 	return imsg_compose_event(iev_net, type, peerid, 0, -1, data,
887 	    datalen);
888 }
889 
890 static int
891 ui_send_fs(int type, uint32_t peerid, const void *data, uint16_t datalen)
892 {
893 	return imsg_compose_event(iev_fs, type, peerid, 0, -1, data,
894 	    datalen);
895 }
896 
897 static void __attribute__((noreturn))
898 usage(int r)
899 {
900 	fprintf(stderr, "USAGE: %s [-hnv] [-c config] [url]\n",
901 	    getprogname());
902 	fprintf(stderr, "version: " PACKAGE " " VERSION "\n");
903 	exit(r);
904 }
905 
906 int
907 main(int argc, char * const *argv)
908 {
909 	struct imsgev	 net_ibuf, fs_ibuf;
910 	int		 pipe2net[2], pipe2fs[2];
911 	int		 ch, configtest = 0, fail = 0;
912 	int		 has_url = 0;
913 	int		 proc = -1;
914 	int		 sessionfd;
915 	char		 path[PATH_MAX];
916 	const char	*url = NEW_TAB_URL;
917 	const char	*argv0;
918 
919 	argv0 = argv[0];
920 
921 	signal(SIGCHLD, SIG_IGN);
922 	signal(SIGPIPE, SIG_IGN);
923 
924 	if (getenv("NO_COLOR") != NULL)
925 		enable_colors = 0;
926 
927 	strlcpy(path, getenv("HOME"), sizeof(path));
928 	strlcat(path, "/.telescope/config", sizeof(path));
929 
930 	while ((ch = getopt_long(argc, argv, opts, longopts, NULL)) != -1) {
931 		switch (ch) {
932 		case 'C':
933 			exit(ui_print_colors());
934 		case 'c':
935 			fail = 1;
936 			strlcpy(path, optarg, sizeof(path));
937 			break;
938 		case 'n':
939 			configtest = 1;
940 			break;
941 		case 'h':
942 			usage(0);
943 		case 'T':
944 			switch (*optarg) {
945 			case 'f':
946 				proc = PROC_FS;
947 				break;
948 			case 'n':
949 				proc = PROC_NET;
950 				break;
951 			default:
952 				errx(1, "invalid process spec %c",
953 				    *optarg);
954 			}
955 			break;
956 		case 'v':
957 			printf("%s %s\n", PACKAGE_NAME, PACKAGE_VERSION);
958 			exit(0);
959 			break;
960 		default:
961 			usage(1);
962 		}
963 	}
964 
965 	argc -= optind;
966 	argv += optind;
967 
968 	if (proc != -1) {
969 		if (argc > 0)
970 			usage(1);
971 		else if (proc == PROC_FS)
972 			return fs_main();
973 		else if (proc == PROC_NET)
974 			return client_main();
975 		else
976 			usage(1);
977 	}
978 
979 	if (argc != 0) {
980 		has_url = 1;
981 		url = argv[0];
982 	}
983 
984 	/* setup keys before reading the config */
985 	TAILQ_INIT(&global_map.m);
986 	global_map.unhandled_input = global_key_unbound;
987 	TAILQ_INIT(&minibuffer_map.m);
988 
989 	config_init();
990 	parseconfig(path, fail);
991 	if (configtest){
992 		puts("config OK");
993 		exit(0);
994 	}
995 
996 	fs_init();
997 	if ((sessionfd = lock_session()) == -1)
998 		errx(1, "can't lock session, is another instance of "
999 		    "telescope already running?");
1000 
1001 	/* Start children. */
1002 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pipe2fs) == -1)
1003 		err(1, "socketpair");
1004 	start_child(PROC_FS, argv0, pipe2fs[1]);
1005 	imsg_init(&fs_ibuf.ibuf, pipe2fs[0]);
1006 	iev_fs = &fs_ibuf;
1007 	iev_fs->handler = handle_dispatch_imsg;
1008 
1009 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pipe2net) == -1)
1010 		err(1, "socketpair");
1011 	start_child(PROC_NET, argv0, pipe2net[1]);
1012 	imsg_init(&net_ibuf.ibuf, pipe2net[0]);
1013 	iev_net = &net_ibuf;
1014 	iev_net->handler = handle_dispatch_imsg;
1015 
1016 	setproctitle("ui");
1017 
1018 	/* initialize tofu & load certificates */
1019 	tofu_init(&certs, 5, offsetof(struct tofu_entry, domain));
1020 	load_certs(&certs);
1021 
1022 	event_init();
1023 
1024 	/* Setup event handlers for pipes to fs/net */
1025 	iev_fs->events = EV_READ;
1026 	event_set(&iev_fs->ev, iev_fs->ibuf.fd, iev_fs->events,
1027 	    iev_fs->handler, iev_fs);
1028 	event_add(&iev_fs->ev, NULL);
1029 
1030 	iev_net->events = EV_READ;
1031 	event_set(&iev_net->ev, iev_net->ibuf.fd, iev_net->events,
1032 	    iev_net->handler, iev_net);
1033 	event_add(&iev_net->ev, NULL);
1034 
1035 	if (ui_init()) {
1036 		load_last_session();
1037 		if (has_url || TAILQ_EMPTY(&tabshead))
1038 			new_tab(url);
1039 
1040 		sandbox_ui_process();
1041 		ui_main_loop();
1042 		ui_end();
1043 	}
1044 
1045 	ui_send_fs(IMSG_QUIT, 0, NULL, 0);
1046 	ui_send_net(IMSG_QUIT, 0, NULL, 0);
1047 	imsg_flush(&iev_fs->ibuf);
1048 	imsg_flush(&iev_net->ibuf);
1049 
1050 	close(sessionfd);
1051 
1052 	return 0;
1053 }