xref: /titanic_41/usr/src/lib/libc/port/gen/pt.c (revision 7257d1b4d25bfac0c802847390e98a464fd787ac)
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 /*	Copyright (c) 1988 AT&T	*/
28 /*	  All Rights Reserved  	*/
29 
30 #pragma ident	"%Z%%M%	%I%	%E% SMI"
31 
32 #pragma weak _ptsname = ptsname
33 #pragma weak _grantpt = grantpt
34 #pragma weak _unlockpt = unlockpt
35 
36 #include "lint.h"
37 #include "libc.h"
38 #include "mtlib.h"
39 #include <sys/types.h>
40 #include <signal.h>
41 #include <sys/param.h>
42 #include <sys/mkdev.h>
43 #include <sys/stream.h>
44 #include <sys/stropts.h>
45 #include <sys/wait.h>
46 #include <sys/signal.h>
47 #include <errno.h>
48 #include <fcntl.h>
49 #include <sys/stat.h>
50 #include <sys/ptms.h>
51 #include <string.h>
52 #include <stdlib.h>
53 #include <unistd.h>
54 #include <wait.h>
55 #include <spawn.h>
56 #include <grp.h>
57 #include "tsd.h"
58 
59 #define	PTSNAME "/dev/pts/"		/* slave name */
60 #define	PTLEN   32			/* slave name length */
61 #define	DEFAULT_TTY_GROUP	"tty"	/* slave device group owner */
62 
63 static void itoa(int, char *);
64 
65 /*
66  *  Check that fd argument is a file descriptor of an opened master.
67  *  Do this by sending an ISPTM ioctl message down stream. Ioctl()
68  *  will fail if:(1) fd is not a valid file descriptor.(2) the file
69  *  represented by fd does not understand ISPTM(not a master device).
70  *  If we have a valid master, get its minor number via fstat().
71  *  Concatenate it to PTSNAME and return it as the name of the slave
72  *  device.
73  */
74 static dev_t
ptsdev(int fd)75 ptsdev(int fd)
76 {
77 	struct stat64 status;
78 	struct strioctl istr;
79 
80 	istr.ic_cmd = ISPTM;
81 	istr.ic_len = 0;
82 	istr.ic_timout = 0;
83 	istr.ic_dp = NULL;
84 
85 	if (ioctl(fd, I_STR, &istr) < 0 || fstat64(fd, &status) < 0)
86 		return (NODEV);
87 
88 	return (minor(status.st_rdev));
89 }
90 
91 char *
ptsname(int fd)92 ptsname(int fd)
93 {
94 	dev_t dev;
95 	char *sname;
96 
97 	if ((dev = ptsdev(fd)) == NODEV)
98 		return (NULL);
99 
100 	sname = tsdalloc(_T_PTSNAME, PTLEN, NULL);
101 	if (sname == NULL)
102 		return (NULL);
103 	(void) strcpy(sname, PTSNAME);
104 	itoa(dev, sname + strlen(PTSNAME));
105 
106 	/*
107 	 * This lookup will create the /dev/pts node (if the corresponding
108 	 * pty exists.
109 	 */
110 	if (access(sname, F_OK) ==  0)
111 		return (sname);
112 
113 	return (NULL);
114 }
115 
116 /*
117  * Send an ioctl down to the master device requesting the
118  * master/slave pair be unlocked.
119  */
120 int
unlockpt(int fd)121 unlockpt(int fd)
122 {
123 	struct strioctl istr;
124 
125 	istr.ic_cmd = UNLKPT;
126 	istr.ic_len = 0;
127 	istr.ic_timout = 0;
128 	istr.ic_dp = NULL;
129 
130 	if (ioctl(fd, I_STR, &istr) < 0)
131 		return (-1);
132 
133 	return (0);
134 }
135 
136 int
grantpt(int fd)137 grantpt(int fd)
138 {
139 	struct strioctl istr;
140 	pt_own_t pto;
141 	struct group *gr_name;
142 
143 	/* validate the file descriptor before proceeding */
144 	if (ptsdev(fd) == NODEV)
145 		return (-1);
146 
147 	pto.pto_ruid = getuid();
148 
149 	gr_name = getgrnam(DEFAULT_TTY_GROUP);
150 	if (gr_name)
151 		pto.pto_rgid = gr_name->gr_gid;
152 	else
153 		pto.pto_rgid = getgid();
154 
155 	istr.ic_cmd = OWNERPT;
156 	istr.ic_len = sizeof (pt_own_t);
157 	istr.ic_timout = 0;
158 	istr.ic_dp = (char *)&pto;
159 
160 	if (ioctl(fd, I_STR, &istr) != 0) {
161 		errno = EACCES;
162 		return (-1);
163 	}
164 
165 	return (0);
166 }
167 
168 /*
169  * Send an ioctl down to the master device requesting the master/slave pair
170  * be assigned to the given zone.
171  */
172 int
zonept(int fd,zoneid_t zoneid)173 zonept(int fd, zoneid_t zoneid)
174 {
175 	struct strioctl istr;
176 
177 	istr.ic_cmd = ZONEPT;
178 	istr.ic_len = sizeof (zoneid);
179 	istr.ic_timout = 0;
180 	istr.ic_dp = (char *)&zoneid;
181 
182 	if (ioctl(fd, I_STR, &istr) != 0) {
183 		return (-1);
184 	}
185 	return (0);
186 }
187 
188 
189 static void
itoa(int i,char * ptr)190 itoa(int i, char *ptr)
191 {
192 	int dig = 0;
193 	int tempi;
194 
195 	tempi = i;
196 	do {
197 		dig++;
198 		tempi /= 10;
199 	} while (tempi);
200 
201 	ptr += dig;
202 	*ptr = '\0';
203 	while (--dig >= 0) {
204 		*(--ptr) = i % 10 + '0';
205 		i /= 10;
206 	}
207 }
208 
209 
210 /*
211  * added for SUSv3 standard
212  *
213  * Open a pseudo-terminal device.  External interface.
214  */
215 
216 int
posix_openpt(int oflag)217 posix_openpt(int oflag)
218 {
219 	return (open("/dev/ptmx", oflag));
220 }
221