1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2008 Ed Schouten <ed@FreeBSD.org> 5 * All rights reserved. 6 * 7 * Portions of this software were developed under sponsorship from Snow 8 * B.V., the Netherlands. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 #ifndef lint 34 __FBSDID("$FreeBSD$"); 35 #endif /* not lint */ 36 37 #include "namespace.h" 38 #include <sys/param.h> 39 #include <sys/ioctl.h> 40 41 #include <errno.h> 42 #include <paths.h> 43 #include <stdlib.h> 44 #include <string.h> 45 #include "un-namespace.h" 46 47 /* 48 * __isptmaster(): return whether the file descriptor refers to a 49 * pseudo-terminal master device. 50 */ 51 static int 52 __isptmaster(int fildes) 53 { 54 55 if (_ioctl(fildes, TIOCPTMASTER) == 0) 56 return (0); 57 58 if (errno != EBADF) 59 errno = EINVAL; 60 61 return (-1); 62 } 63 64 /* 65 * In our implementation, grantpt() and unlockpt() don't actually have 66 * any use, because PTY's are created on the fly and already have proper 67 * permissions upon creation. 68 * 69 * Just make sure `fildes' actually points to a real PTY master device. 70 */ 71 __strong_reference(__isptmaster, grantpt); 72 __strong_reference(__isptmaster, unlockpt); 73 74 /* 75 * ptsname_r(): return the pathname of the slave pseudo-terminal device 76 * associated with the specified master. 77 */ 78 int 79 __ptsname_r(int fildes, char *buffer, size_t buflen) 80 { 81 82 if (buflen <= sizeof(_PATH_DEV)) { 83 errno = ERANGE; 84 return (-1); 85 } 86 87 /* Make sure fildes points to a master device. */ 88 if (__isptmaster(fildes) != 0) 89 return (-1); 90 91 memcpy(buffer, _PATH_DEV, sizeof(_PATH_DEV)); 92 buffer += sizeof(_PATH_DEV) - 1; 93 buflen -= sizeof(_PATH_DEV) - 1; 94 95 if (fdevname_r(fildes, buffer, buflen) == NULL) { 96 if (errno == EINVAL) 97 errno = ERANGE; 98 return (-1); 99 } 100 101 return (0); 102 } 103 104 __strong_reference(__ptsname_r, ptsname_r); 105 106 /* 107 * ptsname(): return the pathname of the slave pseudo-terminal device 108 * associated with the specified master. 109 */ 110 char * 111 ptsname(int fildes) 112 { 113 static char pt_slave[sizeof(_PATH_DEV) + SPECNAMELEN]; 114 115 if (__ptsname_r(fildes, pt_slave, sizeof(pt_slave)) == 0) 116 return (pt_slave); 117 118 return (NULL); 119 } 120