1 /* 2 * Please note: this implementation of openpty() is far from complete. 3 * it is just enough for portable OpenSSH's needs. 4 */ 5 6 /* 7 * Copyright (c) 2004 Damien Miller <djm@mindrot.org> 8 * 9 * Permission to use, copy, modify, and distribute this software for any 10 * purpose with or without fee is hereby granted, provided that the above 11 * copyright notice and this permission notice appear in all copies. 12 * 13 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 14 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 15 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 16 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 17 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 18 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 19 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 20 */ 21 22 /* 23 * Author: Tatu Ylonen <ylo@cs.hut.fi> 24 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland 25 * All rights reserved 26 * Allocating a pseudo-terminal, and making it the controlling tty. 27 * 28 * As far as I am concerned, the code I have written for this software 29 * can be used freely for any purpose. Any derived versions of this 30 * software must be clearly marked as such, and if the derived work is 31 * incompatible with the protocol description in the RFC file, it must be 32 * called by a name other than "ssh" or "Secure Shell". 33 */ 34 35 #include "includes.h" 36 #if !defined(HAVE_OPENPTY) 37 38 #include <sys/types.h> 39 40 #include <stdlib.h> 41 42 #ifdef HAVE_SYS_STAT_H 43 # include <sys/stat.h> 44 #endif 45 #ifdef HAVE_SYS_IOCTL_H 46 # include <sys/ioctl.h> 47 #endif 48 49 #ifdef HAVE_FCNTL_H 50 # include <fcntl.h> 51 #endif 52 53 #ifdef HAVE_UTIL_H 54 # include <util.h> 55 #endif /* HAVE_UTIL_H */ 56 57 #ifdef HAVE_PTY_H 58 # include <pty.h> 59 #endif 60 #if defined(HAVE_DEV_PTMX) && defined(HAVE_SYS_STROPTS_H) 61 # include <sys/stropts.h> 62 #endif 63 64 #include <signal.h> 65 #include <string.h> 66 #include <unistd.h> 67 68 #ifndef O_NOCTTY 69 #define O_NOCTTY 0 70 #endif 71 72 int 73 openpty(int *amaster, int *aslave, char *name, struct termios *termp, 74 struct winsize *winp) 75 { 76 #if defined(HAVE__GETPTY) 77 /* 78 * _getpty(3) exists in SGI Irix 4.x, 5.x & 6.x -- it generates more 79 * pty's automagically when needed 80 */ 81 char *slave; 82 83 if ((slave = _getpty(amaster, O_RDWR, 0622, 0)) == NULL) 84 return (-1); 85 86 /* Open the slave side. */ 87 if ((*aslave = open(slave, O_RDWR | O_NOCTTY)) == -1) { 88 close(*amaster); 89 return (-1); 90 } 91 return (0); 92 93 #elif defined(HAVE_DEV_PTMX) 94 /* 95 * This code is used e.g. on Solaris 2.x. (Note that Solaris 2.3 96 * also has bsd-style ptys, but they simply do not work.) 97 */ 98 int ptm; 99 char *pts; 100 mysig_t old_signal; 101 102 if ((ptm = open("/dev/ptmx", O_RDWR | O_NOCTTY)) == -1) 103 return (-1); 104 105 /* XXX: need to close ptm on error? */ 106 old_signal = signal(SIGCHLD, SIG_DFL); 107 if (grantpt(ptm) < 0) 108 return (-1); 109 signal(SIGCHLD, old_signal); 110 111 if (unlockpt(ptm) < 0) 112 return (-1); 113 114 if ((pts = ptsname(ptm)) == NULL) 115 return (-1); 116 *amaster = ptm; 117 118 /* Open the slave side. */ 119 if ((*aslave = open(pts, O_RDWR | O_NOCTTY)) == -1) { 120 close(*amaster); 121 return (-1); 122 } 123 124 /* 125 * Try to push the appropriate streams modules, as described 126 * in Solaris pts(7). 127 */ 128 ioctl(*aslave, I_PUSH, "ptem"); 129 ioctl(*aslave, I_PUSH, "ldterm"); 130 # ifndef __hpux 131 ioctl(*aslave, I_PUSH, "ttcompat"); 132 # endif /* __hpux */ 133 134 return (0); 135 136 #elif defined(HAVE_DEV_PTS_AND_PTC) 137 /* AIX-style pty code. */ 138 const char *ttname; 139 140 if ((*amaster = open("/dev/ptc", O_RDWR | O_NOCTTY)) == -1) 141 return (-1); 142 if ((ttname = ttyname(*amaster)) == NULL) 143 return (-1); 144 if ((*aslave = open(ttname, O_RDWR | O_NOCTTY)) == -1) { 145 close(*amaster); 146 return (-1); 147 } 148 return (0); 149 150 #else 151 /* BSD-style pty code. */ 152 char ptbuf[64], ttbuf[64]; 153 int i; 154 const char *ptymajors = "pqrstuvwxyzabcdefghijklmno" 155 "ABCDEFGHIJKLMNOPQRSTUVWXYZ"; 156 const char *ptyminors = "0123456789abcdef"; 157 int num_minors = strlen(ptyminors); 158 int num_ptys = strlen(ptymajors) * num_minors; 159 struct termios tio; 160 161 for (i = 0; i < num_ptys; i++) { 162 snprintf(ptbuf, sizeof(ptbuf), "/dev/pty%c%c", 163 ptymajors[i / num_minors], ptyminors[i % num_minors]); 164 snprintf(ttbuf, sizeof(ttbuf), "/dev/tty%c%c", 165 ptymajors[i / num_minors], ptyminors[i % num_minors]); 166 167 if ((*amaster = open(ptbuf, O_RDWR | O_NOCTTY)) == -1) { 168 /* Try SCO style naming */ 169 snprintf(ptbuf, sizeof(ptbuf), "/dev/ptyp%d", i); 170 snprintf(ttbuf, sizeof(ttbuf), "/dev/ttyp%d", i); 171 if ((*amaster = open(ptbuf, O_RDWR | O_NOCTTY)) == -1) 172 continue; 173 } 174 175 /* Open the slave side. */ 176 if ((*aslave = open(ttbuf, O_RDWR | O_NOCTTY)) == -1) { 177 close(*amaster); 178 return (-1); 179 } 180 /* set tty modes to a sane state for broken clients */ 181 if (tcgetattr(*amaster, &tio) != -1) { 182 tio.c_lflag |= (ECHO | ISIG | ICANON); 183 tio.c_oflag |= (OPOST | ONLCR); 184 tio.c_iflag |= ICRNL; 185 tcsetattr(*amaster, TCSANOW, &tio); 186 } 187 188 return (0); 189 } 190 return (-1); 191 #endif 192 } 193 194 #endif /* !defined(HAVE_OPENPTY) */ 195 196