openbsd-compat/bsd-openpty.c

   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 #elif defined(_UNICOS)
 151         char ptbuf[64], ttbuf[64];
 152         int i;
 153         int highpty;
 154
 155         highpty = 128;
 156 #ifdef _SC_CRAY_NPTY
 157         if ((highpty = sysconf(_SC_CRAY_NPTY)) == -1)
 158                 highpty = 128;
 159 #endif /* _SC_CRAY_NPTY */
 160
 161         for (i = 0; i < highpty; i++) {
 162                 snprintf(ptbuf, sizeof(ptbuf), "/dev/pty/%03d", i);
 163                 snprintf(ttbuf, sizeof(ttbuf), "/dev/ttyp%03d", i);
 164                 if ((*amaster = open(ptbuf, O_RDWR|O_NOCTTY)) == -1)
 165                         continue;
 166                 /* Open the slave side. */
 167                 if ((*aslave = open(ttbuf, O_RDWR|O_NOCTTY)) == -1) {
 168                         close(*amaster);
 169                         return (-1);
 170                 }
 171                 return (0);
 172         }
 173         return (-1);
 174
 175 #else
 176         /* BSD-style pty code. */
 177         char ptbuf[64], ttbuf[64];
 178         int i;
 179         const char *ptymajors = "pqrstuvwxyzabcdefghijklmno"
 180             "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
 181         const char *ptyminors = "0123456789abcdef";
 182         int num_minors = strlen(ptyminors);
 183         int num_ptys = strlen(ptymajors) * num_minors;
 184         struct termios tio;
 185
 186         for (i = 0; i < num_ptys; i++) {
 187                 snprintf(ptbuf, sizeof(ptbuf), "/dev/pty%c%c",
 188                     ptymajors[i / num_minors], ptyminors[i % num_minors]);
 189                 snprintf(ttbuf, sizeof(ttbuf), "/dev/tty%c%c",
 190                     ptymajors[i / num_minors], ptyminors[i % num_minors]);
 191
 192                 if ((*amaster = open(ptbuf, O_RDWR | O_NOCTTY)) == -1) {
 193                         /* Try SCO style naming */
 194                         snprintf(ptbuf, sizeof(ptbuf), "/dev/ptyp%d", i);
 195                         snprintf(ttbuf, sizeof(ttbuf), "/dev/ttyp%d", i);
 196                         if ((*amaster = open(ptbuf, O_RDWR | O_NOCTTY)) == -1)
 197                                 continue;
 198                 }
 199
 200                 /* Open the slave side. */
 201                 if ((*aslave = open(ttbuf, O_RDWR | O_NOCTTY)) == -1) {
 202                         close(*amaster);
 203                         return (-1);
 204                 }
 205                 /* set tty modes to a sane state for broken clients */
 206                 if (tcgetattr(*amaster, &tio) != -1) {
 207                         tio.c_lflag |= (ECHO | ISIG | ICANON);
 208                         tio.c_oflag |= (OPOST | ONLCR);
 209                         tio.c_iflag |= ICRNL;
 210                         tcsetattr(*amaster, TCSANOW, &tio);
 211                 }
 212
 213                 return (0);
 214         }
 215         return (-1);
 216 #endif
 217 }
 218
 219 #endif /* !defined(HAVE_OPENPTY) */
 220