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
65 static 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 */
76 static dev_t
77 ptsdev(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
93 char *
94 ptsname(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 */
122 int
123 unlockpt(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 */
157 int
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
177 int
178 grantpt(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 */
213 int
214 zonept(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
230 static void
231 itoa(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
257 int
258 posix_openpt(int oflag)
259 {
260 return (open("/dev/ptmx", oflag));
261 }