1 /*
2  * Copyright (c) 2021 Omar Polo <op@omarpolo.com>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include "compat.h"
18 
19 #include <sys/socket.h>
20 #include <sys/un.h>
21 #include <sys/wait.h>
22 
23 #include <errno.h>
24 #include <fcntl.h>
25 #include <getopt.h>
26 #include <limits.h>
27 #include <signal.h>
28 #include <stdio.h>
29 #include <stdlib.h>
30 #include <string.h>
31 #include <unistd.h>
32 
33 #include "control.h"
34 #include "defaults.h"
35 #include "fs.h"
36 #include "mcache.h"
37 #include "minibuffer.h"
38 #include "parser.h"
39 #include "session.h"
40 #include "telescope.h"
41 #include "ui.h"
42 #include "utils.h"
43 
44 static const struct option longopts[] = {
45 	{"colors",      no_argument,    NULL,   'C'},
46 	{"colours",	no_argument,    NULL,   'C'},
47 	{"help",	no_argument,	NULL,	'h'},
48 	{"safe",	no_argument,	NULL,	'S'},
49 	{"version",	no_argument,	NULL,	'v'},
50 	{NULL,		0,		NULL,	0},
51 };
52 
53 static const char *opts = "Cc:hnST:v";
54 
55 static int	has_url;
56 static char	url[GEMINI_URL_LEN];
57 
58 /*
59  * Used to know when we're finished loading.
60  */
61 int			 operating;
62 
63 /*
64  * "Safe" (or "sandobox") mode.  If enabled, Telescope shouldn't write
65  * anything to the filesystem or execute external programs.
66  */
67 int			safe_mode;
68 
69 static struct imsgev	*iev_net;
70 
71 struct tabshead		 tabshead = TAILQ_HEAD_INITIALIZER(tabshead);
72 struct tabshead		 ktabshead = TAILQ_HEAD_INITIALIZER(ktabshead);
73 struct proxylist	 proxies = TAILQ_HEAD_INITIALIZER(proxies);
74 
75 enum telescope_process {
76 	PROC_UI,
77 	PROC_NET,
78 };
79 
80 #define CANNOT_FETCH		0
81 #define TOO_MUCH_REDIRECTS	1
82 #define MALFORMED_RESPONSE	2
83 #define UNKNOWN_TYPE_OR_CSET	3
84 #define UNKNOWN_PROTOCOL	4
85 
86 /* XXX: keep in sync with normalize_code */
87 const char *err_pages[70] = {
88 	[CANNOT_FETCH]		= "# Couldn't load the page\n",
89 	[TOO_MUCH_REDIRECTS]	= "# Too much redirects\n",
90 	[MALFORMED_RESPONSE]	= "# Got a malformed response\n",
91 	[UNKNOWN_TYPE_OR_CSET]	= "# Unsupported type or charset\n",
92 	[UNKNOWN_PROTOCOL]	= "# Unknown protocol\n",
93 
94 	[10] = "# Input required\n",
95 	[11] = "# Input required\n",
96 	[40] = "# Temporary failure\n",
97 	[41] = "# Server unavailable\n",
98 	[42] = "# CGI error\n",
99 	[43] = "# Proxy error\n",
100 	[44] = "# Slow down\n",
101 	[50] = "# Permanent failure\n",
102 	[51] = "# Not found\n",
103 	[52] = "# Gone\n",
104 	[53] = "# Proxy request refused\n",
105 	[59] = "# Bad request\n",
106 	[60] = "# Client certificate required\n",
107 	[61] = "# Certificate not authorised\n",
108 	[62] = "# Certificate not valid\n"
109 };
110 
111 static void		 die(void) __attribute__((__noreturn__));
112 static struct tab	*tab_by_id(uint32_t);
113 static void		 handle_imsg_err(struct imsg *, size_t);
114 static void		 handle_imsg_check_cert(struct imsg *, size_t);
115 static void		 handle_check_cert_user_choice(int, struct tab *);
116 static void		 handle_maybe_save_new_cert(int, struct tab *);
117 static void		 handle_imsg_got_code(struct imsg *, size_t);
118 static void		 handle_imsg_got_meta(struct imsg *, size_t);
119 static void		 handle_maybe_save_page(int, struct tab *);
120 static void		 handle_save_page_path(const char *, struct tab *);
121 static void		 handle_imsg_buf(struct imsg *, size_t);
122 static void		 handle_imsg_eof(struct imsg *, size_t);
123 static void		 handle_dispatch_imsg(int, short, void *);
124 static int		 load_about_url(struct tab *, const char *);
125 static int		 load_file_url(struct tab *, const char *);
126 static int		 load_finger_url(struct tab *, const char *);
127 static int		 load_gemini_url(struct tab *, const char *);
128 static int		 load_gopher_url(struct tab *, const char *);
129 static int		 load_via_proxy(struct tab *, const char *,
130 			     struct proxy *);
131 static int		 make_request(struct tab *, struct get_req *, int,
132 			     const char *);
133 static int		 do_load_url(struct tab *, const char *, const char *, int);
134 static pid_t		 start_child(enum telescope_process, const char *, int);
135 static void		 send_url(const char *);
136 
137 static const struct proto {
138 	const char	*schema;
139 	const char	*port;
140 	int		 (*loadfn)(struct tab *, const char *);
141 } protos[] = {
142 	{"about",	NULL,	load_about_url},
143 	{"file",	NULL,	load_file_url},
144 	{"finger",	"79",	load_finger_url},
145 	{"gemini",	"1965",	load_gemini_url},
146 	{"gopher",	"70",	load_gopher_url},
147 	{NULL, NULL, NULL},
148 };
149 
150 static imsg_handlerfn *handlers[] = {
151 	[IMSG_ERR] = handle_imsg_err,
152 	[IMSG_CHECK_CERT] = handle_imsg_check_cert,
153 	[IMSG_GOT_CODE] = handle_imsg_got_code,
154 	[IMSG_GOT_META] = handle_imsg_got_meta,
155 	[IMSG_BUF] = handle_imsg_buf,
156 	[IMSG_EOF] = handle_imsg_eof,
157 };
158 
159 static struct ohash	certs;
160 
161 static void __attribute__((__noreturn__))
162 die(void)
163 {
164 	abort(); 		/* TODO */
165 }
166 
167 static struct tab *
168 tab_by_id(uint32_t id)
169 {
170 	struct tab *t;
171 
172 	TAILQ_FOREACH(t, &tabshead, tabs) {
173 		if (t->id == id)
174 			return t;
175 	}
176 
177 	return NULL;
178 }
179 
180 static void
181 handle_imsg_err(struct imsg *imsg, size_t datalen)
182 {
183 	struct tab	*tab;
184 	char		*page;
185 
186 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL)
187 		return;
188 
189 	page = imsg->data;
190 	page[datalen-1] = '\0';
191 
192 	if (asprintf(&page, "# Error loading %s\n\n> %s\n",
193 	    tab->hist_cur->h, page) == -1)
194 		die();
195 	load_page_from_str(tab, page);
196 	free(page);
197 }
198 
199 static void
200 handle_imsg_check_cert(struct imsg *imsg, size_t datalen)
201 {
202 	const char		*hash, *host, *port;
203 	int			 tofu_res;
204 	struct tofu_entry	*e;
205 	struct tab		*tab;
206 
207 	hash = imsg->data;
208 	if (hash[datalen-1] != '\0')
209 		abort();
210 
211 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL)
212 		return;
213 
214 	if (tab->proxy != NULL) {
215 		host = tab->proxy->host;
216 		port = tab->proxy->port;
217 	} else {
218 		host = tab->uri.host;
219 		port = tab->uri.port;
220 	}
221 
222 	if ((e = tofu_lookup(&certs, host, port)) == NULL) {
223 		/* TODO: an update in libressl/libretls changed
224 		 * significantly.  Find a better approach at storing
225 		 * the certs! */
226 		if (datalen > sizeof(e->hash))
227 			abort();
228 
229 		tofu_res = 1;	/* trust on first use */
230 		if ((e = calloc(1, sizeof(*e))) == NULL)
231 			abort();
232 		strlcpy(e->domain, host, sizeof(e->domain));
233 		if (*port != '\0' && strcmp(port, "1965")) {
234 			strlcat(e->domain, ":", sizeof(e->domain));
235 			strlcat(e->domain, port, sizeof(e->domain));
236 		}
237 		strlcpy(e->hash, hash, sizeof(e->hash));
238 		tofu_add(&certs, e);
239 		save_cert(e);
240 	} else
241 		tofu_res = !strcmp(hash, e->hash);
242 
243 	if (tofu_res) {
244 		if (e->verified == -1)
245 			tab->trust = TS_TEMP_TRUSTED;
246 		else if (e->verified == 1)
247 			tab->trust = TS_VERIFIED;
248 		else
249 			tab->trust = TS_TRUSTED;
250 
251 		ui_send_net(IMSG_CERT_STATUS, imsg->hdr.peerid,
252 		    &tofu_res, sizeof(tofu_res));
253 	} else {
254 		tab->trust = TS_UNTRUSTED;
255 		load_page_from_str(tab, "# Certificate mismatch\n");
256 		if ((tab->cert = strdup(hash)) == NULL)
257 			die();
258 		ui_yornp("Certificate mismatch.  Proceed?",
259 		    handle_check_cert_user_choice, tab);
260 	}
261 }
262 
263 static void
264 handle_check_cert_user_choice(int accept, struct tab *tab)
265 {
266 	ui_send_net(IMSG_CERT_STATUS, tab->id, &accept,
267 	    sizeof(accept));
268 
269 	if (accept) {
270 		/*
271 		 * trust the certificate for this session only.  If
272 		 * the page results in a redirect while we're asking
273 		 * the user to save, we'll end up with an invalid
274 		 * tabid (one request == one tab id).  It also makes
275 		 * sense to save it for the current session if the
276 		 * user accepted it.
277 		 */
278 		tofu_temp_trust(&certs, tab->uri.host, tab->uri.port,
279 		    tab->cert);
280 
281 		if (!safe_mode)
282 			ui_yornp("Save the new certificate?",
283 			    handle_maybe_save_new_cert, tab);
284 		else
285 			message("Certificate temporarly trusted");
286 	} else {
287 		free(tab->cert);
288 		tab->cert = NULL;
289 	}
290 }
291 
292 static void
293 handle_maybe_save_new_cert(int accept, struct tab *tab)
294 {
295 	struct tofu_entry *e;
296 	const char *host, *port;
297 
298 	if (tab->proxy != NULL) {
299 		host = tab->proxy->host;
300 		port = tab->proxy->port;
301 	} else {
302 		host = tab->uri.host;
303 		port = tab->uri.port;
304 	}
305 
306 	if (!accept)
307 		goto end;
308 
309 	if ((e = calloc(1, sizeof(*e))) == NULL)
310 		die();
311 
312 	strlcpy(e->domain, host, sizeof(e->domain));
313 	if (*port != '\0' && strcmp(port, "1965")) {
314 		strlcat(e->domain, ":", sizeof(e->domain));
315 		strlcat(e->domain, port, sizeof(e->domain));
316 	}
317 	strlcpy(e->hash, tab->cert, sizeof(e->hash));
318 
319 	update_cert(e);
320 	tofu_update(&certs, e);
321 
322 	tab->trust = TS_TRUSTED;
323 
324 end:
325 	free(tab->cert);
326 	tab->cert = NULL;
327 }
328 
329 static inline int
330 normalize_code(int n)
331 {
332 	if (n < 20) {
333 		if (n == 10 || n == 11)
334 			return n;
335 		return 10;
336 	} else if (n < 30) {
337 		return 20;
338 	} else if (n < 40) {
339 		if (n == 30 || n == 31)
340 			return n;
341 		return 30;
342 	} else if (n < 50) {
343 		if (n <= 44)
344 			return n;
345 		return 40;
346 	} else if (n < 60) {
347 		if (n <= 53 || n == 59)
348 			return n;
349 		return 50;
350 	} else if (n < 70) {
351 		if (n <= 62)
352 			return n;
353 		return 60;
354 	} else
355 		return MALFORMED_RESPONSE;
356 }
357 
358 static void
359 handle_imsg_got_code(struct imsg *imsg, size_t datalen)
360 {
361 	struct tab	*tab;
362 
363 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL)
364 		return;
365 
366 	if (sizeof(tab->code) != datalen)
367 		die();
368 
369 	memcpy(&tab->code, imsg->data, sizeof(tab->code));
370 	tab->code = normalize_code(tab->code);
371 	if (tab->code != 30 && tab->code != 31)
372 		tab->redirect_count = 0;
373 }
374 
375 static void
376 handle_imsg_got_meta(struct imsg *imsg, size_t datalen)
377 {
378 	struct tab	*tab;
379 	char		 buf[128];
380 
381 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL)
382 		return;
383 
384 	if (sizeof(tab->meta) <= datalen)
385 		die();
386 
387 	memcpy(tab->meta, imsg->data, datalen);
388 
389 	if (tab->code < 10) {	/* internal errors */
390 		load_page_from_str(tab, err_pages[tab->code]);
391 	} else if (tab->code < 20) {	/* 1x */
392 		free(tab->last_input_url);
393 		tab->last_input_url = strdup(tab->hist_cur->h);
394 		if (tab->last_input_url == NULL)
395 			die();
396 
397 		load_page_from_str(tab, err_pages[tab->code]);
398 		ui_require_input(tab, tab->code == 11, ir_select_gemini);
399 	} else if (tab->code == 20) {
400 		history_add(tab->hist_cur->h);
401 		if (setup_parser_for(tab)) {
402 			ui_send_net(IMSG_PROCEED, tab->id, NULL, 0);
403 		} else if (safe_mode) {
404 			load_page_from_str(tab,
405 			    err_pages[UNKNOWN_TYPE_OR_CSET]);
406 		} else {
407 			struct hist *h;
408 
409 			if ((h = hist_pop(&tab->hist)) != NULL)
410 				tab->hist_cur = h;
411 			snprintf(buf, sizeof(buf),
412 			    "Can't display \"%s\", save it?", tab->meta);
413 			ui_yornp(buf, handle_maybe_save_page, tab);
414 		}
415 	} else if (tab->code < 40) { /* 3x */
416 		tab->redirect_count++;
417 
418 		/* TODO: make customizable? */
419 		if (tab->redirect_count > 5) {
420 			load_page_from_str(tab,
421 			    err_pages[TOO_MUCH_REDIRECTS]);
422 		} else
423 			do_load_url(tab, tab->meta, NULL, LU_MODE_NOCACHE);
424 	} else { /* 4x, 5x & 6x */
425 		load_page_from_str(tab, err_pages[tab->code]);
426 	}
427 }
428 
429 static void
430 handle_maybe_save_page(int dosave, struct tab *tab)
431 {
432 	const char	*f;
433 	char		 input[PATH_MAX];
434 
435 	/* XXX: this print a message that is confusing  */
436 	ui_on_tab_loaded(tab);
437 
438 	if (!dosave) {
439 		stop_tab(tab);
440 		return;
441 	}
442 
443 	if ((f = strrchr(tab->uri.path, '/')) == NULL)
444 		f = "";
445 	else
446 		f++;
447 
448 	strlcpy(input, download_path, sizeof(input));
449 	strlcat(input, f, sizeof(input));
450 
451 	ui_read("Save to path", handle_save_page_path, tab, input);
452 }
453 
454 static void
455 handle_save_page_path(const char *path, struct tab *tab)
456 {
457 	struct download *d;
458 	int fd;
459 
460 	if (path == NULL) {
461 		stop_tab(tab);
462 		return;
463 	}
464 
465 	ui_show_downloads_pane();
466 
467 	d = enqueue_download(tab->id, path, 0);
468 
469 	/*
470 	 * Change this tab id, the old one is associated with the
471 	 * download now.
472 	 */
473 	tab->id = tab_new_id();
474 
475 	if ((fd = open(path, O_WRONLY|O_TRUNC|O_CREAT, 0644)) == -1)
476 		message("Can't open file %s: %s", d->path, strerror(errno));
477 	else if (d->buffer) {
478 		FILE *fp;
479 		int r;
480 
481 		if ((fp = fdopen(fd, "w")) != NULL) {
482 			r = parser_serialize(current_tab, fp);
483 			if (!r)
484 				message("Failed to save the page.");
485 			fclose(fp);
486 		}
487 
488 		dequeue_first_download();
489 	} else {
490 		d->fd = fd;
491 		ui_send_net(IMSG_PROCEED, d->id, NULL, 0);
492 	}
493 }
494 
495 static void
496 handle_imsg_buf(struct imsg *imsg, size_t datalen)
497 {
498 	struct tab	*tab = NULL;
499 	struct download	*d = NULL;
500 
501 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL &&
502 	    (d = download_by_id(imsg->hdr.peerid)) == NULL)
503 		return;
504 
505 	if (tab != NULL) {
506 		if (!parser_parse(tab, imsg->data, datalen))
507 			die();
508 		ui_on_tab_refresh(tab);
509 	} else {
510 		d->bytes += datalen;
511 		write(d->fd, imsg->data, datalen);
512 		ui_on_download_refresh();
513 	}
514 }
515 
516 static void
517 handle_imsg_eof(struct imsg *imsg, size_t datalen)
518 {
519 	struct tab	*tab = NULL;
520 	struct download	*d = NULL;
521 
522 	if ((tab = tab_by_id(imsg->hdr.peerid)) == NULL &&
523 	    (d = download_by_id(imsg->hdr.peerid)) == NULL)
524 		return;
525 
526 	if (tab != NULL) {
527 		if (!parser_free(tab))
528 			die();
529 		if (has_prefix(tab->hist_cur->h, "gemini://") ||
530 		    has_prefix(tab->hist_cur->h, "gopher://"))
531 			mcache_tab(tab);
532 		ui_on_tab_refresh(tab);
533 		ui_on_tab_loaded(tab);
534 	} else {
535 		close(d->fd);
536 		d->fd = -1;
537 		ui_on_download_refresh();
538 	}
539 }
540 
541 static void
542 handle_dispatch_imsg(int fd, short ev, void *d)
543 {
544 	struct imsgev	*iev = d;
545 
546 	if (dispatch_imsg(iev, ev, handlers, sizeof(handlers)) == -1)
547 		err(1, "connection closed");
548 }
549 
550 static int
551 load_about_url(struct tab *tab, const char *url)
552 {
553 	tab->trust = TS_TRUSTED;
554 	fs_load_url(tab, url);
555 	ui_on_tab_refresh(tab);
556 	ui_on_tab_loaded(tab);
557 	return 0;
558 }
559 
560 static int
561 load_file_url(struct tab *tab, const char *url)
562 {
563 	tab->trust = TS_TRUSTED;
564 	fs_load_url(tab, url);
565 	ui_on_tab_refresh(tab);
566 	ui_on_tab_loaded(tab);
567 	return 0;
568 }
569 
570 static int
571 load_finger_url(struct tab *tab, const char *url)
572 {
573 	struct get_req	 req;
574 	size_t		 len;
575 	char		*at;
576 
577 	memset(&req, 0, sizeof(req));
578 	strlcpy(req.port, tab->uri.port, sizeof(req.port));
579 
580 	/*
581 	 * Sometimes the finger url have the user as path component
582 	 * (e.g. finger://thelambdalab.xyz/plugd), sometimes as
583 	 * userinfo (e.g. finger://cobradile@finger.farm).
584 	 */
585 	if ((at = strchr(tab->uri.host, '@')) != NULL) {
586 		len = at - tab->uri.host;
587 		memcpy(req.req, tab->uri.host, len);
588 
589 		if (len >= sizeof(req.req))
590 			die();
591 		req.req[len] = '\0';
592 
593 		strlcpy(req.host, at+1, sizeof(req.host));
594 	} else {
595 		strlcpy(req.host, tab->uri.host, sizeof(req.host));
596 
597 		/* +1 to skip the initial `/' */
598 		strlcpy(req.req, tab->uri.path+1, sizeof(req.req));
599 	}
600 	strlcat(req.req, "\r\n", sizeof(req.req));
601 
602 	parser_init(tab, textplain_initparser);
603 	return make_request(tab, &req, PROTO_FINGER, NULL);
604 }
605 
606 static int
607 load_gemini_url(struct tab *tab, const char *url)
608 {
609 	struct get_req	 req;
610 
611 	memset(&req, 0, sizeof(req));
612 	strlcpy(req.host, tab->uri.host, sizeof(req.host));
613 	strlcpy(req.port, tab->uri.port, sizeof(req.port));
614 
615 	return make_request(tab, &req, PROTO_GEMINI, tab->hist_cur->h);
616 }
617 
618 static inline const char *
619 gopher_skip_selector(const char *path, int *ret_type)
620 {
621 	*ret_type = 0;
622 
623 	if (!strcmp(path, "/") || *path == '\0') {
624 		*ret_type = '1';
625 		return path;
626 	}
627 
628 	if (*path != '/')
629 		return path;
630 	path++;
631 
632 	switch (*ret_type = *path) {
633 	case '0':
634 	case '1':
635 	case '7':
636 		break;
637 
638 	default:
639 		*ret_type = 0;
640 		path -= 1;
641 		return path;
642 	}
643 
644 	return ++path;
645 }
646 
647 static int
648 load_gopher_url(struct tab *tab, const char *url)
649 {
650 	struct get_req	 req;
651 	int		 type;
652 	const char	*path;
653 
654 	memset(&req, 0, sizeof(req));
655 	strlcpy(req.host, tab->uri.host, sizeof(req.host));
656 	strlcpy(req.port, tab->uri.port, sizeof(req.port));
657 
658 	path = gopher_skip_selector(tab->uri.path, &type);
659 	switch (type) {
660 	case '0':
661 		parser_init(tab, textplain_initparser);
662 		break;
663 	case '1':
664 		parser_init(tab, gophermap_initparser);
665 		break;
666 	case '7':
667 		free(tab->last_input_url);
668 		tab->last_input_url = strdup(url);
669 		if (tab->last_input_url == NULL)
670 			die();
671 		ui_require_input(tab, 0, ir_select_gopher);
672 		return load_page_from_str(tab, err_pages[10]);
673 	default:
674 		return load_page_from_str(tab, "Unknown gopher selector");
675 	}
676 
677 	strlcpy(req.req, path, sizeof(req.req));
678 	if (*tab->uri.query != '\0') {
679 		strlcat(req.req, "?", sizeof(req.req));
680 		strlcat(req.req, tab->uri.query, sizeof(req.req));
681 	}
682 	strlcat(req.req, "\r\n", sizeof(req.req));
683 
684 	return make_request(tab, &req, PROTO_GOPHER, NULL);
685 }
686 
687 static int
688 load_via_proxy(struct tab *tab, const char *url, struct proxy *p)
689 {
690 	struct get_req req;
691 
692 	memset(&req, 0, sizeof(req));
693 	strlcpy(req.host, p->host, sizeof(req.host));
694 	strlcpy(req.port, p->port, sizeof(req.port));
695 
696 	tab->proxy = p;
697 
698 	return make_request(tab, &req, p->proto, tab->hist_cur->h);
699 }
700 
701 static int
702 make_request(struct tab *tab, struct get_req *req, int proto, const char *r)
703 {
704 	stop_tab(tab);
705 	tab->id = tab_new_id();
706 	req->proto = proto;
707 
708 	if (r != NULL) {
709 		strlcpy(req->req, r, sizeof(req->req));
710 		strlcat(req->req, "\r\n", sizeof(req->req));
711 	}
712 
713 	start_loading_anim(tab);
714 	ui_send_net(IMSG_GET_RAW, tab->id, req, sizeof(*req));
715 
716 	/*
717 	 * So the various load_*_url can `return make_request` and
718 	 * do_load_url is happy.
719 	 */
720 	return 1;
721 }
722 
723 void
724 gopher_send_search_req(struct tab *tab, const char *text)
725 {
726 	struct get_req	req;
727 
728 	memset(&req, 0, sizeof(req));
729 	strlcpy(req.host, tab->uri.host, sizeof(req.host));
730 	strlcpy(req.port, tab->uri.port, sizeof(req.port));
731 
732 	/* +2 to skip /7 */
733 	strlcpy(req.req, tab->uri.path+2, sizeof(req.req));
734 	if (*tab->uri.query != '\0') {
735 		strlcat(req.req, "?", sizeof(req.req));
736 		strlcat(req.req, tab->uri.query, sizeof(req.req));
737 	}
738 
739 	strlcat(req.req, "\t", sizeof(req.req));
740 	strlcat(req.req, text, sizeof(req.req));
741 	strlcat(req.req, "\r\n", sizeof(req.req));
742 
743 	erase_buffer(&tab->buffer);
744 	parser_init(tab, gophermap_initparser);
745 
746 	make_request(tab, &req, PROTO_GOPHER, NULL);
747 }
748 
749 int
750 load_page_from_str(struct tab *tab, const char *page)
751 {
752 	parser_init(tab, gemtext_initparser);
753 	if (!tab->buffer.page.parse(&tab->buffer.page, page, strlen(page)))
754 		abort();
755 	if (!tab->buffer.page.free(&tab->buffer.page))
756 		abort();
757 	ui_on_tab_refresh(tab);
758 	ui_on_tab_loaded(tab);
759 	return 0;
760 }
761 
762 /*
763  * Effectively load the given url in the given tab.  Return 1 when
764  * loading the page asynchronously, and thus when an erase_buffer can
765  * be done right after this function return, or 0 when loading the
766  * page synchronously.
767  */
768 static int
769 do_load_url(struct tab *tab, const char *url, const char *base, int mode)
770 {
771 	const struct proto	*p;
772 	struct phos_uri	 uri;
773 	struct proxy	*proxy;
774 	int		 nocache = mode & LU_MODE_NOCACHE;
775 	char		*t;
776 
777 	tab->proxy = NULL;
778 	tab->trust = TS_UNKNOWN;
779 
780 	if (base == NULL)
781 		memcpy(&uri, &tab->uri, sizeof(tab->uri));
782 	else
783 		phos_parse_absolute_uri(base, &uri);
784 
785 	if (!phos_resolve_uri_from_str(&uri, url, &tab->uri)) {
786 		if (asprintf(&t, "#error loading %s\n>%s\n",
787 		    url, "Can't parse the URI") == -1)
788 			die();
789 		strlcpy(tab->hist_cur->h, url, sizeof(tab->hist_cur->h));
790 		load_page_from_str(tab, t);
791 		free(t);
792 		return 0;
793 	}
794 
795 	phos_serialize_uri(&tab->uri, tab->hist_cur->h,
796 	    sizeof(tab->hist_cur->h));
797 
798 	if (!nocache && mcache_lookup(tab->hist_cur->h, tab)) {
799 		ui_on_tab_refresh(tab);
800 		ui_on_tab_loaded(tab);
801 		return 0;
802 	}
803 
804 	for (p = protos; p->schema != NULL; ++p) {
805 		if (!strcmp(tab->uri.scheme, p->schema)) {
806 			/* patch the port */
807 			if (*tab->uri.port == '\0' && p->port != NULL)
808 				strlcpy(tab->uri.port, p->port,
809 				    sizeof(tab->uri.port));
810 
811 			return p->loadfn(tab, tab->hist_cur->h);
812 		}
813 	}
814 
815 	TAILQ_FOREACH(proxy, &proxies, proxies) {
816 		if (!strcmp(tab->uri.scheme, proxy->match_proto))
817 			return load_via_proxy(tab, url, proxy);
818 	}
819 
820 	return load_page_from_str(tab, err_pages[UNKNOWN_PROTOCOL]);
821 }
822 
823 /*
824  * Load url in tab and handle history.  If a tab is marked as lazy, only
825  * prepare the url but don't load it.
826  */
827 void
828 load_url(struct tab *tab, const char *url, const char *base, int mode)
829 {
830 	int lazy = tab->flags & TAB_LAZY;
831 	int nohist = mode & LU_MODE_NOHIST;
832 
833 	if (operating && lazy) {
834 		tab->flags ^= TAB_LAZY;
835 		lazy = 0;
836 	} else if (tab->hist_cur != NULL)
837 		get_scroll_position(tab, &tab->hist_cur->line_off,
838 		    &tab->hist_cur->current_off);
839 
840 	if (!nohist && (!lazy || tab->hist_cur == NULL)) {
841 		if (tab->hist_cur != NULL)
842 			hist_clear_forward(&tab->hist,
843 			    TAILQ_NEXT(tab->hist_cur, entries));
844 
845 		if ((tab->hist_cur = calloc(1, sizeof(*tab->hist_cur)))
846 		    == NULL) {
847 			event_loopbreak();
848 			return;
849 		}
850 
851 		strlcpy(tab->buffer.page.title, url,
852 		    sizeof(tab->buffer.page.title));
853 		hist_push(&tab->hist, tab->hist_cur);
854 
855 		if (lazy)
856 			strlcpy(tab->hist_cur->h, url,
857 			    sizeof(tab->hist_cur->h));
858 	}
859 
860 	if (!lazy)
861 		do_load_url(tab, url, base, mode);
862 }
863 
864 void
865 load_url_in_tab(struct tab *tab, const char *url, const char *base, int mode)
866 {
867 	if (operating) {
868 		autosave_hook();
869 		message("Loading %s...", url);
870 	}
871 
872 	load_url(tab, url, base, mode);
873 }
874 
875 int
876 load_previous_page(struct tab *tab)
877 {
878 	struct hist	*h;
879 
880 	if ((h = TAILQ_PREV(tab->hist_cur, mhisthead, entries)) == NULL)
881 		return 0;
882 	tab->hist_cur = h;
883 	do_load_url(tab, h->h, NULL, LU_MODE_NONE);
884 	return 1;
885 }
886 
887 int
888 load_next_page(struct tab *tab)
889 {
890 	struct hist	*h;
891 
892 	if ((h = TAILQ_NEXT(tab->hist_cur, entries)) == NULL)
893 		return 0;
894 	tab->hist_cur = h;
895 	do_load_url(tab, h->h, NULL, LU_MODE_NONE);
896 	return 1;
897 }
898 
899 void
900 write_buffer(const char *path, struct tab *tab)
901 {
902 	FILE *fp;
903 
904 	if (path == NULL)
905 		return;
906 
907 	if ((fp = fopen(path, "w")) == NULL)
908 		return;
909 	if (!parser_serialize(tab, fp))
910 		message("Failed to save the page.");
911 	fclose(fp);
912 }
913 
914 /*
915  * Given a user-entered URL, apply some heuristics to use it:
916  *
917  * - if it's a proper url use it
918  * - if it starts with a `./' or a `/' assume its a file:// url
919  * - assume it's a gemini:// url
920  *
921  * `ret' (of which len is the size) will be filled with the resulting
922  * url.
923  */
924 void
925 humanify_url(const char *raw, char *ret, size_t len)
926 {
927 	struct phos_uri	uri;
928 	char		buf[PATH_MAX];
929 
930 	if (phos_parse_absolute_uri(raw, &uri)) {
931 		strlcpy(ret, raw, len);
932 		return;
933 	}
934 
935 	if (has_prefix(raw, "./")) {
936 		strlcpy(ret, "file://", len);
937 		getcwd(buf, sizeof(buf));
938 		strlcat(ret, buf, len);
939 		strlcat(ret, "/", len);
940 		strlcat(ret, raw+2, len);
941 		return;
942 	}
943 
944 	if (*raw == '/') {
945 		strlcpy(ret, "file://", len);
946 		strlcat(ret, raw, len);
947 		return;
948 	}
949 
950 	strlcpy(ret, "gemini://", len);
951 	strlcat(ret, raw, len);
952 }
953 
954 static pid_t
955 start_child(enum telescope_process p, const char *argv0, int fd)
956 {
957 	const char	*argv[5];
958 	int		 argc = 0;
959 	pid_t		 pid;
960 
961 	switch (pid = fork()) {
962 	case -1:
963 		die();
964 	case 0:
965 		break;
966 	default:
967 		close(fd);
968 		return pid;
969 	}
970 
971 	if (dup2(fd, 3) == -1)
972 		err(1, "cannot setup imsg fd");
973 
974 	argv[argc++] = argv0;
975 	switch (p) {
976 	case PROC_UI:
977 		errx(1, "Can't start ui process");
978 	case PROC_NET:
979 		argv[argc++] = "-Tn";
980 		break;
981 	}
982 
983 	if (safe_mode)
984 		argv[argc++] = "-S";
985 
986 	argv[argc++] = NULL;
987 	execvp(argv0, (char *const *)argv);
988 	err(1, "execvp(%s)", argv0);
989 }
990 
991 static void
992 send_url(const char *url)
993 {
994 	struct sockaddr_un	 sun;
995 	struct imsgbuf		 ibuf;
996 	int			 ctl_sock;
997 
998 	if ((ctl_sock = socket(AF_UNIX, SOCK_STREAM, 0)) == -1)
999 		err(1, "socket");
1000 
1001 	memset(&sun, 0, sizeof(sun));
1002 	sun.sun_family = AF_UNIX;
1003 	strlcpy(sun.sun_path, ctlsock_path, sizeof(sun.sun_path));
1004 
1005 	if (connect(ctl_sock, (struct sockaddr *)&sun, sizeof(sun)) == -1)
1006 		err(1, "connect: %s", ctlsock_path);
1007 
1008 	imsg_init(&ibuf, ctl_sock);
1009 	imsg_compose(&ibuf, IMSG_CTL_OPEN_URL, 0, 0, -1, url,
1010 	    strlen(url) + 1);
1011 	imsg_flush(&ibuf);
1012 	close(ctl_sock);
1013 }
1014 
1015 int
1016 ui_send_net(int type, uint32_t peerid, const void *data,
1017     uint16_t datalen)
1018 {
1019 	return imsg_compose_event(iev_net, type, peerid, 0, -1, data,
1020 	    datalen);
1021 }
1022 
1023 static void __attribute__((noreturn))
1024 usage(int r)
1025 {
1026 	fprintf(stderr, "USAGE: %s [-ChnSv] [-c config] [url]\n",
1027 	    getprogname());
1028 	fprintf(stderr, "version: " PACKAGE " " VERSION "\n");
1029 	exit(r);
1030 }
1031 
1032 int
1033 main(int argc, char * const *argv)
1034 {
1035 	struct imsgev	 net_ibuf;
1036 	pid_t		 pid;
1037 	int		 control_fd;
1038 	int		 pipe2net[2];
1039 	int		 ch, configtest = 0, fail = 0;
1040 	int		 proc = -1;
1041 	int		 sessionfd = -1;
1042 	int		 status;
1043 	const char	*argv0;
1044 
1045 	argv0 = argv[0];
1046 
1047 	signal(SIGCHLD, SIG_IGN);
1048 	signal(SIGPIPE, SIG_IGN);
1049 
1050 	if (getenv("NO_COLOR") != NULL)
1051 		enable_colors = 0;
1052 
1053 	while ((ch = getopt_long(argc, argv, opts, longopts, NULL)) != -1) {
1054 		switch (ch) {
1055 		case 'C':
1056 			exit(ui_print_colors());
1057 		case 'c':
1058 			fail = 1;
1059 			strlcpy(config_path, optarg, sizeof(config_path));
1060 			break;
1061 		case 'n':
1062 			configtest = 1;
1063 			break;
1064 		case 'h':
1065 			usage(0);
1066 		case 'S':
1067 			safe_mode = 1;
1068 			break;
1069 		case 'T':
1070 			switch (*optarg) {
1071 			case 'n':
1072 				proc = PROC_NET;
1073 				break;
1074 			default:
1075 				errx(1, "invalid process spec %c",
1076 				    *optarg);
1077 			}
1078 			break;
1079 		case 'v':
1080 			printf("%s %s\n", PACKAGE_NAME, PACKAGE_VERSION);
1081 			exit(0);
1082 			break;
1083 		default:
1084 			usage(1);
1085 		}
1086 	}
1087 
1088 	argc -= optind;
1089 	argv += optind;
1090 
1091 	if (proc != -1) {
1092 		if (argc > 0)
1093 			usage(1);
1094 		else if (proc == PROC_NET)
1095 			return net_main();
1096 		else
1097 			usage(1);
1098 	}
1099 
1100 	if (argc != 0) {
1101 		has_url = 1;
1102 		humanify_url(argv[0], url, sizeof(url));
1103 	}
1104 
1105 	fs_init();
1106 
1107 	/* setup keys before reading the config */
1108 	TAILQ_INIT(&global_map.m);
1109 	global_map.unhandled_input = global_key_unbound;
1110 	TAILQ_INIT(&minibuffer_map.m);
1111 
1112 	config_init();
1113 	parseconfig(config_path, fail);
1114 	if (configtest) {
1115 		puts("config OK");
1116 		exit(0);
1117 	}
1118 
1119 	if (download_path == NULL &&
1120 	    (download_path = strdup("/tmp/")) == NULL)
1121 		errx(1, "strdup");
1122 
1123 	if (!safe_mode && (sessionfd = lock_session()) == -1) {
1124 		if (has_url) {
1125 			send_url(url);
1126 			exit(0);
1127 		}
1128 
1129 		errx(1, "can't lock session, is another instance of "
1130 		    "telescope already running?");
1131 	}
1132 
1133 	/* Start children. */
1134 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pipe2net) == -1)
1135 		err(1, "socketpair");
1136 	start_child(PROC_NET, argv0, pipe2net[1]);
1137 	imsg_init(&net_ibuf.ibuf, pipe2net[0]);
1138 	iev_net = &net_ibuf;
1139 	iev_net->handler = handle_dispatch_imsg;
1140 
1141 	setproctitle("ui");
1142 
1143 	/* initialize tofu store */
1144 	tofu_init(&certs, 5, offsetof(struct tofu_entry, domain));
1145 
1146 	event_init();
1147 
1148 	if (!safe_mode) {
1149 		if ((control_fd = control_init(ctlsock_path)) == -1)
1150 			err(1, "control_init %s", ctlsock_path);
1151 		control_listen(control_fd);
1152 	}
1153 
1154 	/* initialize the in-memory cache store */
1155 	mcache_init();
1156 
1157 	/* Setup event handler for the autosave */
1158 	autosave_init();
1159 
1160 	/* Setup event handlers for pipes to net */
1161 	iev_net->events = EV_READ;
1162 	event_set(&iev_net->ev, iev_net->ibuf.fd, iev_net->events,
1163 	    iev_net->handler, iev_net);
1164 	event_add(&iev_net->ev, NULL);
1165 
1166 	if (ui_init()) {
1167 		sandbox_ui_process();
1168 		fs_load_state(&certs);
1169 		operating = 1;
1170 		switch_to_tab(current_tab);
1171 		ui_main_loop();
1172 		ui_end();
1173 	}
1174 
1175 	ui_send_net(IMSG_QUIT, 0, NULL, 0);
1176 	imsg_flush(&iev_net->ibuf);
1177 
1178 	/* wait for children to terminate */
1179 	do {
1180 		pid = wait(&status);
1181 		if (pid == -1) {
1182 			if (errno != EINTR && errno != ECHILD)
1183 				err(1, "wait");
1184 		} else if (WIFSIGNALED(status))
1185 			warnx("child terminated; signal %d", WTERMSIG(status));
1186 	} while (pid != -1 || (pid == -1 && errno == EINTR));
1187 
1188 	if (!safe_mode)
1189 		unlink(crashed_file);
1190 
1191 	if (!safe_mode && close(sessionfd) == -1)
1192 		err(1, "close(sessionfd = %d)", sessionfd);
1193 
1194 	return 0;
1195 }