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Date:: Sun Jul 25 11:06:51 2021 UTC
Message:: initial gopher support
Actions:: History | Blame | Raw File
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 struct tabshead		 tabshead = TAILQ_HEAD_INITIALIZER(tabshead);
48 struct proxylist	 proxies = TAILQ_HEAD_INITIALIZER(proxies);
49 
50 enum telescope_process {
51 	PROC_UI,
52 	PROC_FS,
53 	PROC_NET,
54 };
55 
56 #define CANNOT_FETCH		0
57 #define TOO_MUCH_REDIRECTS	1
58 #define MALFORMED_RESPONSE	2
59 #define UNKNOWN_TYPE_OR_CSET	3
60 #define UNKNOWN_PROTOCOL	4
61 
62 /* XXX: keep in sync with telescope.c:/^normalize_code/ */
63 const char *err_pages[70] = {
64 	[CANNOT_FETCH]		= "# Couldn't load the page\n",
65 	[TOO_MUCH_REDIRECTS]	= "# Too much redirects\n",
66 	[MALFORMED_RESPONSE]	= "# Got a malformed response\n",
67 	[UNKNOWN_TYPE_OR_CSET]	= "# Unsupported type or charset\n",
68 	[UNKNOWN_PROTOCOL]	= "# Unknown protocol\n",
69 
70 	[10] = "# Input required\n",
71 	[11] = "# Input required\n",
72 	[40] = "# Temporary failure\n",
73 	[41] = "# Server unavailable\n",
74 	[42] = "# CGI error\n",
75 	[43] = "# Proxy error\n",
76 	[44] = "# Slow down\n",
77 	[50] = "# Permanent failure\n",
78 	[51] = "# Not found\n",
79 	[52] = "# Gone\n",
80 	[53] = "# Proxy request refused\n",
81 	[59] = "# Bad request\n",
82 	[60] = "# Client certificate required\n",
83 	[61] = "# Certificate not authorised\n",
84 	[62] = "# Certificate not valid\n"
85 };
86 
87 static void		 die(void) __attribute__((__noreturn__));
88 static struct tab	*tab_by_id(uint32_t);
89 static void		 handle_imsg_err(struct imsg*, size_t);
90 static void		 handle_imsg_check_cert(struct imsg*, size_t);
91 static void		 handle_check_cert_user_choice(int, struct tab *);
92 static void		 handle_maybe_save_new_cert(int, struct tab *);
93 static void		 handle_imsg_got_code(struct imsg*, size_t);
94 static void		 handle_imsg_got_meta(struct imsg*, size_t);
95 static void		 handle_maybe_save_page(int, struct tab *);
96 static void		 handle_save_page_path(const char *, struct tab *);
97 static void		 handle_imsg_file_opened(struct imsg*, size_t);
98 static void		 handle_imsg_buf(struct imsg*, size_t);
99 static void		 handle_imsg_eof(struct imsg*, size_t);
100 static void		 handle_imsg_bookmark_ok(struct imsg*, size_t);
101 static void		 handle_imsg_save_cert_ok(struct imsg*, size_t);
102 static void		 handle_imsg_update_cert_ok(struct imsg *, size_t);
103 static void		 handle_dispatch_imsg(int, short, void*);
104 static void		 load_page_from_str(struct tab*, const char*);
105 static void		 load_about_url(struct tab*, const char*);
106 static void		 load_finger_url(struct tab *, const char *);
107 static void		 load_gemini_url(struct tab*, const char*);
108 static void		 load_gopher_url(struct tab *, const char *);
109 static void		 load_via_proxy(struct tab *, const char *,
110 			     struct proxy *);
111 static void		 make_request(struct tab *, struct get_req *, int,
112 			     const char *);
113 static int		 do_load_url(struct tab*, const char *, const char *);
114 static void		 parse_session_line(char *, const char **, uint32_t *);
115 static void		 load_last_session(void);
116 static pid_t		 start_child(enum telescope_process, const char *, int);
117 static int		 ui_send_net(int, uint32_t, const void *, uint16_t);
118 static int		 ui_send_fs(int, uint32_t, const void *, uint16_t);
119 
120 static struct proto {
121 	const char	*schema;
122 	const char	*port;
123 	void		 (*loadfn)(struct tab*, const char*);
124 } protos[] = {
125 	{"about",	NULL,	load_about_url},
126 	{"finger",	"79",	load_finger_url},
127 	{"gemini",	"1965",	load_gemini_url},
128 	{"gopher",	"70",	load_gopher_url},
129 	{NULL, NULL, NULL},
130 };
131 
132 static imsg_handlerfn *handlers[] = {
133 	[IMSG_ERR] = handle_imsg_err,
134 	[IMSG_CHECK_CERT] = handle_imsg_check_cert,
135 	[IMSG_GOT_CODE] = handle_imsg_got_code,
136 	[IMSG_GOT_META] = handle_imsg_got_meta,
137 	[IMSG_BUF] = handle_imsg_buf,
138 	[IMSG_EOF] = handle_imsg_eof,
139 	[IMSG_BOOKMARK_OK] = handle_imsg_bookmark_ok,
140 	[IMSG_SAVE_CERT_OK] = handle_imsg_save_cert_ok,
141 	[IMSG_UPDATE_CERT_OK] = handle_imsg_update_cert_ok,
142 	[IMSG_FILE_OPENED] = handle_imsg_file_opened,
143 };
144 
145 static struct ohash	certs;
146 
147 static void __attribute__((__noreturn__))
148 die(void)
149 {
150 	abort(); 		/* TODO */
151 }
152 
153 static struct tab *
154 tab_by_id(uint32_t id)
155 {
156 	struct tab *t;
157 
158 	TAILQ_FOREACH(t, &tabshead, tabs) {
159 		if (t->id == id)
160 			return t;
161 	}
162 
163 	return NULL;
164 }
165 
166 static void
167 handle_imsg_err(struct imsg *imsg, size_t datalen)
168 {
169 	struct tab	*tab;
170 	char		*page;
171 
172 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL)
173 		return;
174 
175 	page = imsg->data;
176 	page[datalen-1] = '\0';
177 
178 	if (asprintf(&page, "# Error loading %s\n\n> %s\n",
179 	    tab->hist_cur->h, page) == -1)
180 		die();
181 	load_page_from_str(tab, page);
182 	free(page);
183 }
184 
185 static void
186 handle_imsg_check_cert(struct imsg *imsg, size_t datalen)
187 {
188 	const char		*hash, *host, *port;
189 	int			 tofu_res;
190 	struct tofu_entry	*e;
191 	struct tab		*tab;
192 
193 	hash = imsg->data;
194 	if (hash[datalen-1] != '\0')
195 		abort();
196 
197 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL)
198 		return;
199 
200 	if (tab->proxy != NULL) {
201 		host = tab->proxy->host;
202 		port = tab->proxy->port;
203 	} else {
204 		host = tab->uri.host;
205 		port = tab->uri.port;
206 	}
207 
208 	if ((e = tofu_lookup(&certs, host, port)) == NULL) {
209 		/* TODO: an update in libressl/libretls changed
210 		 * significantly.  Find a better approach at storing
211 		 * the certs! */
212 		if (datalen > sizeof(e->hash))
213 			abort();
214 
215 		tofu_res = 1;	/* trust on first use */
216 		if ((e = calloc(1, sizeof(*e))) == NULL)
217 			abort();
218 		strlcpy(e->domain, host, sizeof(e->domain));
219 		if (*port != '\0' && strcmp(port, "1965")) {
220 			strlcat(e->domain, ":", sizeof(e->domain));
221 			strlcat(e->domain, port, sizeof(e->domain));
222 		}
223 		strlcpy(e->hash, hash, sizeof(e->hash));
224 		tofu_add(&certs, e);
225 		ui_send_fs(IMSG_SAVE_CERT, tab->id, e, sizeof(*e));
226 	} else
227 		tofu_res = !strcmp(hash, e->hash);
228 
229 	if (tofu_res) {
230 		if (e->verified == -1)
231 			tab->trust = TS_TEMP_TRUSTED;
232 		else if (e->verified == 1)
233 			tab->trust = TS_VERIFIED;
234 		else
235 			tab->trust = TS_TRUSTED;
236 
237 		ui_send_net(IMSG_CERT_STATUS, imsg->hdr.peerid,
238 		    &tofu_res, sizeof(tofu_res));
239 	} else {
240 		tab->trust = TS_UNTRUSTED;
241 		load_page_from_str(tab, "# Certificate mismatch\n");
242 		if ((tab->cert = strdup(hash)) == NULL)
243 			die();
244 		ui_yornp("Certificate mismatch.  Proceed?",
245 		    handle_check_cert_user_choice, tab);
246 	}
247 }
248 
249 static void
250 handle_check_cert_user_choice(int accept, struct tab *tab)
251 {
252 	ui_send_net(IMSG_CERT_STATUS, tab->id, &accept,
253 	    sizeof(accept));
254 
255 	if (accept) {
256 		/*
257 		 * trust the certificate for this session only.  If
258 		 * the page results in a redirect while we're asking
259 		 * the user to save, we'll end up with an invalid
260 		 * tabid (one request == one tab id) and crash.  It
261 		 * also makes sense to save it for the current session
262 		 * if the user accepted it.
263 		 */
264 		tofu_temp_trust(&certs, tab->uri.host, tab->uri.port, tab->cert);
265 
266 		ui_yornp("Save the new certificate?",
267 		    handle_maybe_save_new_cert, tab);
268 	} else {
269 		free(tab->cert);
270 		tab->cert = NULL;
271 	}
272 }
273 
274 static void
275 handle_maybe_save_new_cert(int accept, struct tab *tab)
276 {
277 	struct tofu_entry *e;
278 	const char *host, *port;
279 
280 	if (tab->proxy != NULL) {
281 		host = tab->proxy->host;
282 		port = tab->proxy->port;
283 	} else {
284 		host = tab->uri.host;
285 		port = tab->uri.port;
286 	}
287 
288 	if (!accept)
289 		goto end;
290 
291 	if ((e = calloc(1, sizeof(*e))) == NULL)
292 		die();
293 
294 	strlcpy(e->domain, host, sizeof(e->domain));
295 	if (*port != '\0' && strcmp(port, "1965")) {
296 		strlcat(e->domain, ":", sizeof(e->domain));
297 		strlcat(e->domain, port, sizeof(e->domain));
298 	}
299 	strlcpy(e->hash, tab->cert, sizeof(e->hash));
300 	ui_send_fs(IMSG_UPDATE_CERT, 0, e, sizeof(*e));
301 
302 	tofu_update(&certs, e);
303 
304 	tab->trust = TS_TRUSTED;
305 
306 end:
307 	free(tab->cert);
308 	tab->cert = NULL;
309 }
310 
311 static inline int
312 normalize_code(int n)
313 {
314 	if (n < 20) {
315 		if (n == 10 || n == 11)
316 			return n;
317 		return 10;
318 	} else if (n < 30) {
319 		return 20;
320 	} else if (n < 40) {
321 		if (n == 30 || n == 31)
322 			return n;
323 		return 30;
324 	} else if (n < 50) {
325 		if (n <= 44)
326 			return n;
327 		return 40;
328 	} else if (n < 60) {
329 		if (n <= 53 || n == 59)
330 			return n;
331 		return 50;
332 	} else if (n < 70) {
333 		if (n <= 62)
334 			return n;
335 		return 60;
336 	} else
337 		return MALFORMED_RESPONSE;
338 }
339 
340 static void
341 handle_imsg_got_code(struct imsg *imsg, size_t datalen)
342 {
343 	struct tab	*tab;
344 
345 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL)
346 		return;
347 
348 	if (sizeof(tab->code) != datalen)
349 		die();
350 
351 	memcpy(&tab->code, imsg->data, sizeof(tab->code));
352 	tab->code = normalize_code(tab->code);
353 	if (tab->code != 30 && tab->code != 31)
354 		tab->redirect_count = 0;
355 }
356 
357 static void
358 handle_imsg_got_meta(struct imsg *imsg, size_t datalen)
359 {
360 	struct tab	*tab;
361 
362 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL)
363 		return;
364 
365 	if (sizeof(tab->meta) <= datalen)
366 		die();
367 
368 	memcpy(tab->meta, imsg->data, datalen);
369 
370 	if (tab->code < 10) {	/* internal errors */
371 		load_page_from_str(tab, err_pages[tab->code]);
372 	} else if (tab->code < 20) {	/* 1x */
373 		load_page_from_str(tab, err_pages[tab->code]);
374 		ui_require_input(tab, tab->code == 11);
375 	} else if (tab->code == 20) {
376 		if (setup_parser_for(tab)) {
377 			ui_send_net(IMSG_PROCEED, tab->id, NULL, 0);
378 		} else {
379 			load_page_from_str(tab, err_pages[UNKNOWN_TYPE_OR_CSET]);
380 			ui_yornp("Can't display page, wanna save?",
381 			    handle_maybe_save_page, tab);
382 		}
383 	} else if (tab->code < 40) { /* 3x */
384 		tab->redirect_count++;
385 
386 		/* TODO: make customizable? */
387 		if (tab->redirect_count > 5) {
388 			load_page_from_str(tab,
389 			    err_pages[TOO_MUCH_REDIRECTS]);
390 		} else
391 			do_load_url(tab, tab->meta, NULL);
392 	} else { /* 4x, 5x & 6x */
393 		load_page_from_str(tab, err_pages[tab->code]);
394 	}
395 }
396 
397 static void
398 handle_maybe_save_page(int dosave, struct tab *tab)
399 {
400 	if (dosave)
401 		ui_read("Save to path", handle_save_page_path, tab);
402 	else
403 		stop_tab(tab);
404 }
405 
406 static void
407 handle_save_page_path(const char *path, struct tab *tab)
408 {
409 	if (path == NULL) {
410 		stop_tab(tab);
411 		return;
412 	}
413 
414 	tab->path = strdup(path);
415 
416 	ui_send_fs(IMSG_FILE_OPEN, tab->id, path, strlen(path)+1);
417 }
418 
419 static void
420 handle_imsg_file_opened(struct imsg *imsg, size_t datalen)
421 {
422 	struct tab	*tab;
423 	char		*page;
424 	const char	*e;
425 	int		 l;
426 
427 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL) {
428 		if (imsg->fd != -1)
429 			close(imsg->fd);
430 		return;
431 	}
432 
433 	if (imsg->fd == -1) {
434 		stop_tab(tab);
435 
436 		e = imsg->data;
437 		if (e[datalen-1] != '\0')
438 			die();
439 		l = asprintf(&page, "# Can't open file\n\n> %s: %s\n",
440 		    tab->path, e);
441 		if (l == -1)
442 			die();
443 		load_page_from_str(tab, page);
444 		free(page);
445 	} else {
446 		tab->fd = imsg->fd;
447 		ui_send_net(IMSG_PROCEED, tab->id, NULL, 0);
448 	}
449 }
450 
451 static void
452 handle_imsg_buf(struct imsg *imsg, size_t datalen)
453 {
454 	struct tab	*tab;
455 	int		 l;
456 	char		*page, buf[FMT_SCALED_STRSIZE] = {0};
457 
458 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL)
459 		return;
460 
461 	tab->bytes += datalen;
462 	if (tab->fd == -1) {
463 		if (!tab->buffer.page.parse(&tab->buffer.page,
464 		    imsg->data, datalen))
465 			die();
466 	} else {
467 		write(tab->fd, imsg->data, datalen);
468 		fmt_scaled(tab->bytes, buf);
469 		l = asprintf(&page, "Saving to \"%s\"... (%s)\n",
470 		    tab->path,
471 		    buf);
472 		if (l == -1)
473 			die();
474 		load_page_from_str(tab, page);
475 		free(page);
476 	}
477 
478 	ui_on_tab_refresh(tab);
479 }
480 
481 static void
482 handle_imsg_eof(struct imsg *imsg, size_t datalen)
483 {
484 	struct tab	*tab;
485 	int		 l;
486 	char		*page, buf[FMT_SCALED_STRSIZE] = {0};
487 
488 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL)
489 		return;
490 
491 	if (tab->fd == -1) {
492 		if (!tab->buffer.page.free(&tab->buffer.page))
493 			die();
494 	} else {
495 		fmt_scaled(tab->bytes, buf);
496 		l = asprintf(&page, "Saved to \"%s\" (%s)\n",
497 		    tab->path,
498 		    buf);
499 		if (l == -1)
500 			die();
501 		load_page_from_str(tab, page);
502 		free(page);
503 
504 		close(tab->fd);
505 		tab->fd = -1;
506 		free(tab->path);
507 		tab->path = NULL;
508 	}
509 
510 	ui_on_tab_refresh(tab);
511 	ui_on_tab_loaded(tab);
512 }
513 
514 static void
515 handle_imsg_bookmark_ok(struct imsg *imsg, size_t datalen)
516 {
517 	int res;
518 
519 	if (datalen != sizeof(res))
520 		die();
521 
522 	memcpy(&res, imsg->data, sizeof(res));
523 	if (res == 0)
524 		message("Added to bookmarks!");
525 	else
526 		message("Failed to add to bookmarks: %s",
527 		    strerror(res));
528 }
529 
530 static void
531 handle_imsg_save_cert_ok(struct imsg *imsg, size_t datalen)
532 {
533 	int res;
534 
535 	if (datalen != sizeof(res))
536 		die();
537 	memcpy(&res, imsg->data, datalen);
538 	if (res != 0)
539 		message("Failed to save the cert for: %s",
540 		    strerror(res));
541 }
542 
543 static void
544 handle_imsg_update_cert_ok(struct imsg *imsg, size_t datalen)
545 {
546 	int res;
547 
548 	if (datalen != sizeof(res))
549 		die();
550 	memcpy(&res, imsg->data, datalen);
551 	if (!res)
552 		message("Failed to update the certificate");
553 }
554 
555 static void
556 handle_dispatch_imsg(int fd, short ev, void *d)
557 {
558 	struct imsgev	*iev = d;
559 
560 	if (dispatch_imsg(iev, ev, handlers, sizeof(handlers)) == -1)
561 		err(1, "connection closed");
562 }
563 
564 static void
565 load_page_from_str(struct tab *tab, const char *page)
566 {
567 	erase_buffer(&tab->buffer);
568 	gemtext_initparser(&tab->buffer.page);
569 	if (!tab->buffer.page.parse(&tab->buffer.page, page, strlen(page)))
570 		die();
571 	if (!tab->buffer.page.free(&tab->buffer.page))
572 		die();
573 	ui_on_tab_refresh(tab);
574 	ui_on_tab_loaded(tab);
575 }
576 
577 static void
578 load_about_url(struct tab *tab, const char *url)
579 {
580 	tab->trust = TS_VERIFIED;
581 
582 	gemtext_initparser(&tab->buffer.page);
583 
584 	ui_send_fs(IMSG_GET, tab->id,
585 	    tab->hist_cur->h, strlen(tab->hist_cur->h)+1);
586 }
587 
588 static void
589 load_finger_url(struct tab *tab, const char *url)
590 {
591 	struct get_req	 req;
592 	size_t		 len;
593 	char		*at;
594 
595 	memset(&req, 0, sizeof(req));
596 	strlcpy(req.port, tab->uri.port, sizeof(req.port));
597 
598 	/*
599 	 * Sometimes the finger url have the user as path component
600 	 * (e.g. finger://thelambdalab.xyz/plugd), sometimes as
601 	 * userinfo (e.g. finger://cobradile@finger.farm).
602 	 */
603 	if ((at = strchr(tab->uri.host, '@')) != NULL) {
604 		len = at - tab->uri.host;
605 		memcpy(req.req, tab->uri.host, len);
606 
607 		if (len >= sizeof(req.req))
608 			die();
609 		req.req[len] = '\0';
610 
611 		strlcpy(req.host, at+1, sizeof(req.host));
612 	} else {
613 		strlcpy(req.host, tab->uri.host, sizeof(req.host));
614 
615 		/* +1 to skip the initial `/' */
616 		strlcpy(req.req, tab->uri.path+1, sizeof(req.req));
617 	}
618 	strlcat(req.req, "\r\n", sizeof(req.req));
619 
620 	textplain_initparser(&tab->buffer.page);
621 	make_request(tab, &req, PROTO_FINGER, NULL);
622 }
623 
624 static void
625 load_gemini_url(struct tab *tab, const char *url)
626 {
627 	struct get_req	 req;
628 
629 	memset(&req, 0, sizeof(req));
630 	strlcpy(req.host, tab->uri.host, sizeof(req.host));
631 	strlcpy(req.port, tab->uri.port, sizeof(req.host));
632 
633 	make_request(tab, &req, PROTO_GEMINI, tab->hist_cur->h);
634 }
635 
636 static void
637 load_gopher_url(struct tab *tab, const char *url)
638 {
639 	struct get_req	req;
640 
641 	memset(&req, 0, sizeof(req));
642 	strlcpy(req.host, tab->uri.host, sizeof(req.host));
643 	strlcpy(req.port, tab->uri.port, sizeof(req.host));
644 
645 	/* cheat a bit by considering gophermaps text */
646 	textplain_initparser(&tab->buffer.page);
647 	make_request(tab, &req, PROTO_GOPHER, tab->uri.path);
648 }
649 
650 static void
651 load_via_proxy(struct tab *tab, const char *url, struct proxy *p)
652 {
653 	struct get_req req;
654 
655 	memset(&req, 0, sizeof(req));
656 	strlcpy(req.host, p->host, sizeof(req.host));
657 	strlcpy(req.port, p->port, sizeof(req.host));
658 
659 	tab->proxy = p;
660 
661 	make_request(tab, &req, p->proto, tab->hist_cur->h);
662 }
663 
664 static void
665 make_request(struct tab *tab, struct get_req *req, int proto, const char *r)
666 {
667 	stop_tab(tab);
668 	tab->id = tab_new_id();
669 	req->proto = proto;
670 
671 	if (r != NULL) {
672 		strlcpy(req->req, r, sizeof(req->req));
673 		strlcat(req->req, "\r\n", sizeof(req->req));
674 	}
675 
676 	ui_send_net(IMSG_GET_RAW, tab->id, req, sizeof(*req));
677 }
678 
679 /*
680  * Effectively load the given url in the given tab.  Return 1 when
681  * loading the page asynchronously, and thus when an erase_buffer can
682  * be done right after this function return, or 0 when loading the
683  * page synchronously.  In this last case, erase_buffer *MUST* be
684  * called by the handling function (such as load_page_from_str).
685  */
686 static int
687 do_load_url(struct tab *tab, const char *url, const char *base)
688 {
689 	struct phos_uri	 uri;
690 	struct proto	*p;
691 	struct proxy	*proxy;
692 	char		*t;
693 
694 	tab->proxy = NULL;
695 
696 	if (tab->fd != -1) {
697 		close(tab->fd);
698 		tab->fd = -1;
699 		free(tab->path);
700 		tab->path = NULL;
701 	}
702 
703 	tab->trust = TS_UNKNOWN;
704 
705 	if (base == NULL)
706 		memcpy(&uri, &tab->uri, sizeof(tab->uri));
707 	else
708 		phos_parse_absolute_uri(base, &uri);
709 
710 	if (!phos_resolve_uri_from_str(&uri, url, &tab->uri)) {
711 		if (asprintf(&t, "#error loading %s\n>%s\n",
712 		    url, "Can't parse the URI") == -1)
713 			die();
714 		strlcpy(tab->hist_cur->h, url, sizeof(tab->hist_cur->h));
715 		load_page_from_str(tab, t);
716 		free(t);
717 		return 0;
718 	}
719 
720 	phos_serialize_uri(&tab->uri, tab->hist_cur->h,
721 	    sizeof(tab->hist_cur->h));
722 
723 	for (p = protos; p->schema != NULL; ++p) {
724 		if (!strcmp(tab->uri.scheme, p->schema)) {
725 			/* patch the port */
726 			if (*tab->uri.port == '\0' && p->port != NULL)
727 				strlcpy(tab->uri.port, p->port,
728 				    sizeof(tab->uri.port));
729 
730 			p->loadfn(tab, url);
731                         return 1;
732 		}
733 	}
734 
735 	TAILQ_FOREACH(proxy, &proxies, proxies) {
736 		if (!strcmp(tab->uri.scheme, proxy->match_proto)) {
737 			load_via_proxy(tab, url, proxy);
738 			return 1;
739 		}
740 	}
741 
742 	load_page_from_str(tab, err_pages[UNKNOWN_PROTOCOL]);
743 	return 0;
744 }
745 
746 /*
747  * Load url in tab.  If tab is marked as lazy, only prepare the url
748  * but don't load it.  If tab is lazy and a url was already prepared,
749  * do load it!
750  */
751 void
752 load_url(struct tab *tab, const char *url, const char *base)
753 {
754 	int lazy;
755 
756 	lazy = tab->flags & TAB_LAZY;
757 
758 	if (lazy && tab->hist_cur != NULL) {
759 		lazy = 0;
760 		tab->flags &= ~TAB_LAZY;
761 	}
762 
763 	if (!lazy || tab->hist_cur == NULL) {
764 		if (tab->hist_cur != NULL)
765 			hist_clear_forward(&tab->hist,
766 			    TAILQ_NEXT(tab->hist_cur, entries));
767 
768 		if ((tab->hist_cur = calloc(1, sizeof(*tab->hist_cur))) == NULL) {
769 			event_loopbreak();
770 			return;
771 		}
772 
773 		strlcpy(tab->buffer.page.title, url,
774 		    sizeof(tab->buffer.page.title));
775 		hist_push(&tab->hist, tab->hist_cur);
776 
777 		if (lazy)
778 			strlcpy(tab->hist_cur->h, url,
779 			    sizeof(tab->hist_cur->h));
780 	}
781 
782 	if (!lazy && do_load_url(tab, url, base))
783 		erase_buffer(&tab->buffer);
784 }
785 
786 int
787 load_previous_page(struct tab *tab)
788 {
789 	struct hist	*h;
790 
791 	if ((h = TAILQ_PREV(tab->hist_cur, mhisthead, entries)) == NULL)
792 		return 0;
793 	tab->hist_cur = h;
794 	do_load_url(tab, h->h, NULL);
795 	return 1;
796 }
797 
798 int
799 load_next_page(struct tab *tab)
800 {
801 	struct hist	*h;
802 
803 	if ((h = TAILQ_NEXT(tab->hist_cur, entries)) == NULL)
804 		return 0;
805 	tab->hist_cur = h;
806 	do_load_url(tab, h->h, NULL);
807 	return 1;
808 }
809 
810 /*
811  * Free every resource linked to the tab, including the tab itself.
812  * Removes the tab from the tablist, but doesn't update the
813  * current_tab though.
814  */
815 void
816 free_tab(struct tab *tab)
817 {
818 	stop_tab(tab);
819 
820 	if (evtimer_pending(&tab->loadingev, NULL))
821 		evtimer_del(&tab->loadingev);
822 
823 	TAILQ_REMOVE(&tabshead, tab, tabs);
824 	free(tab);
825 }
826 
827 void
828 stop_tab(struct tab *tab)
829 {
830 	ui_send_net(IMSG_STOP, tab->id, NULL, 0);
831 
832 	if (tab->fd != -1) {
833 		close(tab->fd);
834 		tab->fd = -1;
835 		free(tab->path);
836 		tab->path = NULL;
837 		load_page_from_str(tab, "Stopped.\n");
838 	}
839 }
840 
841 void
842 add_to_bookmarks(const char *str)
843 {
844 	ui_send_fs(IMSG_BOOKMARK_PAGE, 0,
845 	    str, strlen(str)+1);
846 }
847 
848 void
849 save_session(void)
850 {
851 	struct tab	*tab;
852 	char		*t;
853 	int		 flags;
854 
855 	ui_send_fs(IMSG_SESSION_START, 0, NULL, 0);
856 
857 	TAILQ_FOREACH(tab, &tabshead, tabs) {
858 		flags = tab->flags;
859 		if (tab == current_tab)
860 			flags |= TAB_CURRENT;
861 
862 		t = tab->hist_cur->h;
863 		ui_send_fs(IMSG_SESSION_TAB, flags, t, strlen(t)+1);
864 
865 		t = tab->buffer.page.title;
866 		ui_send_fs(IMSG_SESSION_TAB_TITLE, 0, t, strlen(t)+1);
867 	}
868 
869 	ui_send_fs(IMSG_SESSION_END, 0, NULL, 0);
870 }
871 
872 /*
873  * Parse a line of the session file.  The format is:
874  *
875  *	URL [flags,...] [title]\n
876  */
877 static void
878 parse_session_line(char *line, const char **title, uint32_t *flags)
879 {
880 	char *s, *t, *ap;
881 
882 	*title = "";
883 	*flags = 0;
884 	if ((s = strchr(line, ' ')) == NULL)
885 		return;
886 
887 	*s++ = '\0';
888 
889         if ((t = strchr(s, ' ')) != NULL) {
890 		*t++ = '\0';
891 		*title = t;
892 	}
893 
894 	while ((ap = strsep(&s, ",")) != NULL) {
895 		if (*ap == '\0')
896 			;
897 		else if (!strcmp(ap, "current"))
898 			*flags |= TAB_CURRENT;
899 		else
900 			message("unknown tab flag: %s", ap);
901 	}
902 }
903 
904 static void
905 load_last_session(void)
906 {
907 	const char	*title;
908 	char		*nl, *line = NULL;
909 	uint32_t	 flags;
910 	size_t		 linesize = 0;
911 	ssize_t		 linelen;
912 	FILE		*session;
913 	struct tab	*tab, *curr = NULL;
914 
915 	if ((session = fopen(session_file, "r")) == NULL) {
916 		/* first time? */
917 		new_tab("about:new", NULL);
918 		switch_to_tab(new_tab("about:help", NULL));
919 		return;
920 	}
921 
922 	while ((linelen = getline(&line, &linesize, session)) != -1) {
923                 if ((nl = strchr(line, '\n')) != NULL)
924 			*nl = '\0';
925 		parse_session_line(line, &title, &flags);
926 		if ((tab = new_tab(line, NULL)) == NULL)
927 			err(1, "new_tab");
928                 strlcpy(tab->buffer.page.title, title,
929 		    sizeof(tab->buffer.page.title));
930 		if (flags & TAB_CURRENT)
931 			curr = tab;
932 	}
933 
934 	if (ferror(session))
935 		message("error reading %s: %s",
936 		    session_file, strerror(errno));
937 	fclose(session);
938 	free(line);
939 
940 	if (curr != NULL)
941 		switch_to_tab(curr);
942 
943 	if (last_time_crashed())
944 		switch_to_tab(new_tab("about:crash", NULL));
945 
946 	return;
947 }
948 
949 static pid_t
950 start_child(enum telescope_process p, const char *argv0, int fd)
951 {
952 	const char	*argv[4];
953 	int		 argc = 0;
954 	pid_t		 pid;
955 
956 	switch (pid = fork()) {
957 	case -1:
958 		die();
959 	case 0:
960 		break;
961 	default:
962 		close(fd);
963 		return pid;
964 	}
965 
966 	if (dup2(fd, 3) == -1)
967 		err(1, "cannot setup imsg fd");
968 
969 	argv[argc++] = argv0;
970 	switch (p) {
971 	case PROC_UI:
972 		errx(1, "Can't start ui process");
973 	case PROC_FS:
974 		argv[argc++] = "-Tf";
975 		break;
976 	case PROC_NET:
977 		argv[argc++] = "-Tn";
978 		break;
979 	}
980 
981 	argv[argc++] = NULL;
982 	execvp(argv0, (char *const *)argv);
983 	err(1, "execvp(%s)", argv0);
984 }
985 
986 static int
987 ui_send_net(int type, uint32_t peerid, const void *data,
988     uint16_t datalen)
989 {
990 	return imsg_compose_event(iev_net, type, peerid, 0, -1, data,
991 	    datalen);
992 }
993 
994 static int
995 ui_send_fs(int type, uint32_t peerid, const void *data, uint16_t datalen)
996 {
997 	return imsg_compose_event(iev_fs, type, peerid, 0, -1, data,
998 	    datalen);
999 }
1000 
1001 static void __attribute__((noreturn))
1002 usage(int r)
1003 {
1004 	fprintf(stderr, "USAGE: %s [-hnv] [-c config] [url]\n",
1005 	    getprogname());
1006 	fprintf(stderr, "version: " PACKAGE " " VERSION "\n");
1007 	exit(r);
1008 }
1009 
1010 int
1011 main(int argc, char * const *argv)
1012 {
1013 	struct imsgev	 net_ibuf, fs_ibuf;
1014 	int		 pipe2net[2], pipe2fs[2];
1015 	int		 ch, configtest = 0, fail = 0;
1016 	int		 has_url = 0;
1017 	int		 proc = -1;
1018 	int		 sessionfd;
1019 	char		 path[PATH_MAX];
1020 	const char	*url = NEW_TAB_URL;
1021 	const char	*argv0;
1022 
1023 	argv0 = argv[0];
1024 
1025 	signal(SIGCHLD, SIG_IGN);
1026 	signal(SIGPIPE, SIG_IGN);
1027 
1028 	if (getenv("NO_COLOR") != NULL)
1029 		enable_colors = 0;
1030 
1031 	strlcpy(path, getenv("HOME"), sizeof(path));
1032 	strlcat(path, "/.telescope/config", sizeof(path));
1033 
1034 	while ((ch = getopt_long(argc, argv, opts, longopts, NULL)) != -1) {
1035 		switch (ch) {
1036 		case 'C':
1037 			exit(ui_print_colors());
1038 		case 'c':
1039 			fail = 1;
1040 			strlcpy(path, optarg, sizeof(path));
1041 			break;
1042 		case 'n':
1043 			configtest = 1;
1044 			break;
1045 		case 'h':
1046 			usage(0);
1047 		case 'T':
1048 			switch (*optarg) {
1049 			case 'f':
1050 				proc = PROC_FS;
1051 				break;
1052 			case 'n':
1053 				proc = PROC_NET;
1054 				break;
1055 			default:
1056 				errx(1, "invalid process spec %c",
1057 				    *optarg);
1058 			}
1059 			break;
1060 		case 'v':
1061 			printf("%s %s\n", PACKAGE_NAME, PACKAGE_VERSION);
1062 			exit(0);
1063 			break;
1064 		default:
1065 			usage(1);
1066 		}
1067 	}
1068 
1069 	argc -= optind;
1070 	argv += optind;
1071 
1072 	if (proc != -1) {
1073 		if (argc > 0)
1074 			usage(1);
1075 		else if (proc == PROC_FS)
1076 			return fs_main();
1077 		else if (proc == PROC_NET)
1078 			return net_main();
1079 		else
1080 			usage(1);
1081 	}
1082 
1083 	if (argc != 0) {
1084 		has_url = 1;
1085 		url = argv[0];
1086 	}
1087 
1088 	/* setup keys before reading the config */
1089 	TAILQ_INIT(&global_map.m);
1090 	global_map.unhandled_input = global_key_unbound;
1091 	TAILQ_INIT(&minibuffer_map.m);
1092 
1093 	config_init();
1094 	parseconfig(path, fail);
1095 	if (configtest){
1096 		puts("config OK");
1097 		exit(0);
1098 	}
1099 
1100 	fs_init();
1101 	if ((sessionfd = lock_session()) == -1)
1102 		errx(1, "can't lock session, is another instance of "
1103 		    "telescope already running?");
1104 
1105 	/* Start children. */
1106 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pipe2fs) == -1)
1107 		err(1, "socketpair");
1108 	start_child(PROC_FS, argv0, pipe2fs[1]);
1109 	imsg_init(&fs_ibuf.ibuf, pipe2fs[0]);
1110 	iev_fs = &fs_ibuf;
1111 	iev_fs->handler = handle_dispatch_imsg;
1112 
1113 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pipe2net) == -1)
1114 		err(1, "socketpair");
1115 	start_child(PROC_NET, argv0, pipe2net[1]);
1116 	imsg_init(&net_ibuf.ibuf, pipe2net[0]);
1117 	iev_net = &net_ibuf;
1118 	iev_net->handler = handle_dispatch_imsg;
1119 
1120 	setproctitle("ui");
1121 
1122 	/* initialize tofu & load certificates */
1123 	tofu_init(&certs, 5, offsetof(struct tofu_entry, domain));
1124 	load_certs(&certs);
1125 
1126 	event_init();
1127 
1128 	/* Setup event handlers for pipes to fs/net */
1129 	iev_fs->events = EV_READ;
1130 	event_set(&iev_fs->ev, iev_fs->ibuf.fd, iev_fs->events,
1131 	    iev_fs->handler, iev_fs);
1132 	event_add(&iev_fs->ev, NULL);
1133 
1134 	iev_net->events = EV_READ;
1135 	event_set(&iev_net->ev, iev_net->ibuf.fd, iev_net->events,
1136 	    iev_net->handler, iev_net);
1137 	event_add(&iev_net->ev, NULL);
1138 
1139 	if (ui_init()) {
1140 		load_last_session();
1141 		if (has_url || TAILQ_EMPTY(&tabshead))
1142 			new_tab(url, NULL);
1143 
1144 		sandbox_ui_process();
1145 		ui_main_loop();
1146 		ui_end();
1147 	}
1148 
1149 	ui_send_fs(IMSG_QUIT, 0, NULL, 0);
1150 	ui_send_net(IMSG_QUIT, 0, NULL, 0);
1151 	imsg_flush(&iev_fs->ibuf);
1152 	imsg_flush(&iev_net->ibuf);
1153 
1154 	close(sessionfd);
1155 
1156 	return 0;
1157 }