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