1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2011 NetApp, Inc.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY NETAPP, INC ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL NETAPP, INC OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 *
28 * $FreeBSD$
29 */
30
31#include <sys/cdefs.h>
32__FBSDID("$FreeBSD$");
33
34#include <sys/types.h>
35#ifndef WITHOUT_CAPSICUM
36#include <sys/capsicum.h>
37#endif
38#include <sys/select.h>
39
40#ifndef WITHOUT_CAPSICUM
41#include <capsicum_helpers.h>
42#endif
43#include <err.h>
44#include <errno.h>
45#include <stdio.h>
46#include <stdlib.h>
47#include <termios.h>
48#include <unistd.h>
49#include <stdbool.h>
50#include <sysexits.h>
51
52#include "inout.h"
53#include "pci_lpc.h"
54#include "debug.h"
55
56#define	BVM_CONSOLE_PORT	0x220
57#define	BVM_CONS_SIG		('b' << 8 | 'v')
58
59static struct termios tio_orig, tio_new;
60
61static void
62ttyclose(void)
63{
64	tcsetattr(STDIN_FILENO, TCSANOW, &tio_orig);
65}
66
67static void
68ttyopen(void)
69{
70	tcgetattr(STDIN_FILENO, &tio_orig);
71
72	cfmakeraw(&tio_new);
73	tcsetattr(STDIN_FILENO, TCSANOW, &tio_new);
74	raw_stdio = 1;
75
76	atexit(ttyclose);
77}
78
79static bool
80tty_char_available(void)
81{
82	fd_set rfds;
83	struct timeval tv;
84
85	FD_ZERO(&rfds);
86	FD_SET(STDIN_FILENO, &rfds);
87	tv.tv_sec = 0;
88	tv.tv_usec = 0;
89	if (select(STDIN_FILENO + 1, &rfds, NULL, NULL, &tv) > 0) {
90		return (true);
91	} else {
92		return (false);
93	}
94}
95
96static int
97ttyread(void)
98{
99	char rb;
100
101	if (tty_char_available()) {
102		read(STDIN_FILENO, &rb, 1);
103		return (rb & 0xff);
104	} else {
105		return (-1);
106	}
107}
108
109static void
110ttywrite(unsigned char wb)
111{
112	(void) write(STDOUT_FILENO, &wb, 1);
113}
114
115static int
116console_handler(struct vmctx *ctx, int vcpu, int in, int port, int bytes,
117		uint32_t *eax, void *arg)
118{
119	static int opened;
120#ifndef WITHOUT_CAPSICUM
121	cap_rights_t rights;
122	cap_ioctl_t cmds[] = { TIOCGETA, TIOCSETA, TIOCGWINSZ };
123#endif
124
125	if (bytes == 2 && in) {
126		*eax = BVM_CONS_SIG;
127		return (0);
128	}
129
130	/*
131	 * Guests might probe this port to look for old ISA devices
132	 * using single-byte reads.  Return 0xff for those.
133	 */
134	if (bytes == 1 && in) {
135		*eax = 0xff;
136		return (0);
137	}
138
139	if (bytes != 4)
140		return (-1);
141
142	if (!opened) {
143#ifndef WITHOUT_CAPSICUM
144		cap_rights_init(&rights, CAP_EVENT, CAP_IOCTL, CAP_READ,
145		    CAP_WRITE);
146		if (caph_rights_limit(STDIN_FILENO, &rights) == -1)
147			errx(EX_OSERR, "Unable to apply rights for sandbox");
148		if (caph_ioctls_limit(STDIN_FILENO, cmds, nitems(cmds)) == -1)
149			errx(EX_OSERR, "Unable to apply rights for sandbox");
150#endif
151		ttyopen();
152		opened = 1;
153	}
154
155	if (in)
156		*eax = ttyread();
157	else
158		ttywrite(*eax);
159
160	return (0);
161}
162
163SYSRES_IO(BVM_CONSOLE_PORT, 4);
164
165static struct inout_port consport = {
166	"bvmcons",
167	BVM_CONSOLE_PORT,
168	1,
169	IOPORT_F_INOUT,
170	console_handler
171};
172
173void
174init_bvmcons(void)
175{
176
177	register_inout(&consport);
178}
179