1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22/*
23 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26
27/*
28 * Copyright 2020 OmniOS Community Edition (OmniOSce) Association.
29 */
30
31/*	Copyright (c) 1988 AT&T	*/
32/*	  All Rights Reserved	*/
33
34#pragma weak _ptsname = ptsname
35#pragma weak _grantpt = grantpt
36#pragma weak _unlockpt = unlockpt
37
38#include "lint.h"
39#include "libc.h"
40#include "mtlib.h"
41#include <sys/types.h>
42#include <signal.h>
43#include <sys/param.h>
44#include <sys/mkdev.h>
45#include <sys/stream.h>
46#include <sys/stropts.h>
47#include <sys/wait.h>
48#include <sys/signal.h>
49#include <errno.h>
50#include <fcntl.h>
51#include <sys/stat.h>
52#include <sys/ptms.h>
53#include <string.h>
54#include <stdlib.h>
55#include <unistd.h>
56#include <wait.h>
57#include <spawn.h>
58#include <grp.h>
59#include "tsd.h"
60
61#define	PTSNAME "/dev/pts/"		/* slave name */
62#define	PTLEN   32			/* slave name length */
63#define	DEFAULT_TTY_GROUP	"tty"	/* slave device group owner */
64
65static void itoa(int, char *);
66
67/*
68 *  Check that fd argument is a file descriptor of an opened master.
69 *  Do this by sending an ISPTM ioctl message down stream. Ioctl()
70 *  will fail if:(1) fd is not a valid file descriptor.(2) the file
71 *  represented by fd does not understand ISPTM(not a master device).
72 *  If we have a valid master, get its minor number via fstat().
73 *  Concatenate it to PTSNAME and return it as the name of the slave
74 *  device.
75 */
76static dev_t
77ptsdev(int fd)
78{
79	struct stat64 status;
80	struct strioctl istr;
81
82	istr.ic_cmd = ISPTM;
83	istr.ic_len = 0;
84	istr.ic_timout = 0;
85	istr.ic_dp = NULL;
86
87	if (ioctl(fd, I_STR, &istr) < 0 || fstat64(fd, &status) < 0)
88		return (NODEV);
89
90	return (minor(status.st_rdev));
91}
92
93char *
94ptsname(int fd)
95{
96	dev_t dev;
97	char *sname;
98
99	if ((dev = ptsdev(fd)) == NODEV)
100		return (NULL);
101
102	sname = tsdalloc(_T_PTSNAME, PTLEN, NULL);
103	if (sname == NULL)
104		return (NULL);
105	(void) strcpy(sname, PTSNAME);
106	itoa(dev, sname + strlen(PTSNAME));
107
108	/*
109	 * This lookup will create the /dev/pts node (if the corresponding
110	 * pty exists.
111	 */
112	if (access(sname, F_OK) ==  0)
113		return (sname);
114
115	return (NULL);
116}
117
118/*
119 * Send an ioctl down to the master device requesting the
120 * master/slave pair be unlocked.
121 */
122int
123unlockpt(int fd)
124{
125	struct strioctl istr;
126
127	istr.ic_cmd = UNLKPT;
128	istr.ic_len = 0;
129	istr.ic_timout = 0;
130	istr.ic_dp = NULL;
131
132	if (ioctl(fd, I_STR, &istr) < 0)
133		return (-1);
134
135	return (0);
136}
137
138/*
139 * XPG4v2 requires that open of a slave pseudo terminal device
140 * provides the process with an interface that is identical to
141 * the terminal interface.
142 *
143 * To satisfy this, in strict XPG4v2 mode, this routine also sends
144 * a message down the stream that sets a flag in the kernel module
145 * so that additional actions are performed when opening an
146 * associated slave PTY device. When this happens, modules are
147 * automatically pushed onto the stream to provide terminal
148 * semantics and those modules are then informed that they should
149 * behave in strict XPG4v2 mode which modifies their behaviour. In
150 * particular, in strict XPG4v2 mode, empty blocks will be sent up
151 * the master side of the stream rather than being suppressed.
152 *
153 * Most applications do not expect this behaviour so it is only
154 * enabled for programs compiled in strict XPG4v2 mode (see
155 * stdlib.h).
156 */
157int
158__unlockpt_xpg4(int fd)
159{
160	int ret;
161
162	if ((ret = unlockpt(fd)) == 0) {
163		struct strioctl istr;
164
165		istr.ic_cmd = PTSSTTY;
166		istr.ic_len = 0;
167		istr.ic_timout = 0;
168		istr.ic_dp = NULL;
169
170		if (ioctl(fd, I_STR, &istr) < 0)
171			ret = -1;
172	}
173
174	return (ret);
175}
176
177int
178grantpt(int fd)
179{
180	struct strioctl istr;
181	pt_own_t pto;
182	struct group *gr_name;
183
184	/* validate the file descriptor before proceeding */
185	if (ptsdev(fd) == NODEV)
186		return (-1);
187
188	pto.pto_ruid = getuid();
189
190	gr_name = getgrnam(DEFAULT_TTY_GROUP);
191	if (gr_name)
192		pto.pto_rgid = gr_name->gr_gid;
193	else
194		pto.pto_rgid = getgid();
195
196	istr.ic_cmd = OWNERPT;
197	istr.ic_len = sizeof (pt_own_t);
198	istr.ic_timout = 0;
199	istr.ic_dp = (char *)&pto;
200
201	if (ioctl(fd, I_STR, &istr) != 0) {
202		errno = EACCES;
203		return (-1);
204	}
205
206	return (0);
207}
208
209/*
210 * Send an ioctl down to the master device requesting the master/slave pair
211 * be assigned to the given zone.
212 */
213int
214zonept(int fd, zoneid_t zoneid)
215{
216	struct strioctl istr;
217
218	istr.ic_cmd = ZONEPT;
219	istr.ic_len = sizeof (zoneid);
220	istr.ic_timout = 0;
221	istr.ic_dp = (char *)&zoneid;
222
223	if (ioctl(fd, I_STR, &istr) != 0) {
224		return (-1);
225	}
226	return (0);
227}
228
229
230static void
231itoa(int i, char *ptr)
232{
233	int dig = 0;
234	int tempi;
235
236	tempi = i;
237	do {
238		dig++;
239		tempi /= 10;
240	} while (tempi);
241
242	ptr += dig;
243	*ptr = '\0';
244	while (--dig >= 0) {
245		*(--ptr) = i % 10 + '0';
246		i /= 10;
247	}
248}
249
250
251/*
252 * added for SUSv3 standard
253 *
254 * Open a pseudo-terminal device.  External interface.
255 */
256
257int
258posix_openpt(int oflag)
259{
260	return (open("/dev/ptmx", oflag));
261}
262