| /* |
| * |
| * pty.c |
| * |
| * Author: Tatu Ylonen <ylo@cs.hut.fi> |
| * |
| * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland |
| * All rights reserved |
| * |
| * Created: Fri Mar 17 04:37:25 1995 ylo |
| * |
| * Allocating a pseudo-terminal, and making it the controlling tty. |
| * |
| */ |
| |
| #include "includes.h" |
| RCSID("$Id: pty.c,v 1.13 2000/03/02 12:31:50 damien Exp $"); |
| |
| #ifdef HAVE_UTIL_H |
| # include <util.h> |
| #endif /* HAVE_UTIL_H */ |
| |
| #include "pty.h" |
| #include "ssh.h" |
| |
| /* Pty allocated with _getpty gets broken if we do I_PUSH:es to it. */ |
| #if defined(HAVE__GETPTY) || defined(HAVE_OPENPTY) |
| #undef HAVE_DEV_PTMX |
| #endif |
| |
| #ifdef HAVE_PTY_H |
| # include <pty.h> |
| #endif |
| #if defined(HAVE_DEV_PTMX) && defined(HAVE_SYS_STROPTS_H) |
| # include <sys/stropts.h> |
| #endif |
| |
| #ifndef O_NOCTTY |
| #define O_NOCTTY 0 |
| #endif |
| |
| /* |
| * Allocates and opens a pty. Returns 0 if no pty could be allocated, or |
| * nonzero if a pty was successfully allocated. On success, open file |
| * descriptors for the pty and tty sides and the name of the tty side are |
| * returned (the buffer must be able to hold at least 64 characters). |
| */ |
| |
| int |
| pty_allocate(int *ptyfd, int *ttyfd, char *namebuf, int namebuflen) |
| { |
| #if defined(HAVE_OPENPTY) || defined(BSD4_4) |
| /* openpty(3) exists in OSF/1 and some other os'es */ |
| char buf[64]; |
| int i; |
| |
| i = openpty(ptyfd, ttyfd, buf, NULL, NULL); |
| if (i < 0) { |
| error("openpty: %.100s", strerror(errno)); |
| return 0; |
| } |
| strlcpy(namebuf, buf, namebuflen); /* possible truncation */ |
| return 1; |
| #else /* HAVE_OPENPTY */ |
| #ifdef HAVE__GETPTY |
| /* |
| * _getpty(3) exists in SGI Irix 4.x, 5.x & 6.x -- it generates more |
| * pty's automagically when needed |
| */ |
| char *slave; |
| |
| slave = _getpty(ptyfd, O_RDWR, 0622, 0); |
| if (slave == NULL) { |
| error("_getpty: %.100s", strerror(errno)); |
| return 0; |
| } |
| strlcpy(namebuf, slave, namebuflen); |
| /* Open the slave side. */ |
| *ttyfd = open(namebuf, O_RDWR | O_NOCTTY); |
| if (*ttyfd < 0) { |
| error("%.200s: %.100s", namebuf, strerror(errno)); |
| close(*ptyfd); |
| return 0; |
| } |
| return 1; |
| #else /* HAVE__GETPTY */ |
| #if defined(HAVE_DEV_PTMX) |
| /* |
| * This code is used e.g. on Solaris 2.x. (Note that Solaris 2.3 |
| * also has bsd-style ptys, but they simply do not work.) |
| */ |
| int ptm; |
| char *pts; |
| |
| ptm = open("/dev/ptmx", O_RDWR | O_NOCTTY); |
| if (ptm < 0) { |
| error("/dev/ptmx: %.100s", strerror(errno)); |
| return 0; |
| } |
| if (grantpt(ptm) < 0) { |
| error("grantpt: %.100s", strerror(errno)); |
| return 0; |
| } |
| if (unlockpt(ptm) < 0) { |
| error("unlockpt: %.100s", strerror(errno)); |
| return 0; |
| } |
| pts = ptsname(ptm); |
| if (pts == NULL) |
| error("Slave pty side name could not be obtained."); |
| strlcpy(namebuf, pts, namebuflen); |
| *ptyfd = ptm; |
| |
| /* Open the slave side. */ |
| *ttyfd = open(namebuf, O_RDWR | O_NOCTTY); |
| if (*ttyfd < 0) { |
| error("%.100s: %.100s", namebuf, strerror(errno)); |
| close(*ptyfd); |
| return 0; |
| } |
| /* Push the appropriate streams modules, as described in Solaris pts(7). */ |
| if (ioctl(*ttyfd, I_PUSH, "ptem") < 0) |
| error("ioctl I_PUSH ptem: %.100s", strerror(errno)); |
| if (ioctl(*ttyfd, I_PUSH, "ldterm") < 0) |
| error("ioctl I_PUSH ldterm: %.100s", strerror(errno)); |
| if (ioctl(*ttyfd, I_PUSH, "ttcompat") < 0) |
| error("ioctl I_PUSH ttcompat: %.100s", strerror(errno)); |
| return 1; |
| #else /* HAVE_DEV_PTMX */ |
| #ifdef HAVE_DEV_PTS_AND_PTC |
| /* AIX-style pty code. */ |
| const char *name; |
| |
| *ptyfd = open("/dev/ptc", O_RDWR | O_NOCTTY); |
| if (*ptyfd < 0) { |
| error("Could not open /dev/ptc: %.100s", strerror(errno)); |
| return 0; |
| } |
| name = ttyname(*ptyfd); |
| if (!name) |
| fatal("Open of /dev/ptc returns device for which ttyname fails."); |
| strlcpy(namebuf, name, namebuflen); |
| *ttyfd = open(name, O_RDWR | O_NOCTTY); |
| if (*ttyfd < 0) { |
| error("Could not open pty slave side %.100s: %.100s", |
| name, strerror(errno)); |
| close(*ptyfd); |
| return 0; |
| } |
| return 1; |
| #else /* HAVE_DEV_PTS_AND_PTC */ |
| /* BSD-style pty code. */ |
| char buf[64]; |
| int i; |
| const char *ptymajors = "pqrstuvwxyzabcdefghijklmnoABCDEFGHIJKLMNOPQRSTUVWXYZ"; |
| const char *ptyminors = "0123456789abcdef"; |
| int num_minors = strlen(ptyminors); |
| int num_ptys = strlen(ptymajors) * num_minors; |
| |
| for (i = 0; i < num_ptys; i++) { |
| snprintf(buf, sizeof buf, "/dev/pty%c%c", ptymajors[i / num_minors], |
| ptyminors[i % num_minors]); |
| *ptyfd = open(buf, O_RDWR | O_NOCTTY); |
| if (*ptyfd < 0) |
| continue; |
| snprintf(namebuf, namebuflen, "/dev/tty%c%c", |
| ptymajors[i / num_minors], ptyminors[i % num_minors]); |
| |
| /* Open the slave side. */ |
| *ttyfd = open(namebuf, O_RDWR | O_NOCTTY); |
| if (*ttyfd < 0) { |
| error("%.100s: %.100s", namebuf, strerror(errno)); |
| close(*ptyfd); |
| return 0; |
| } |
| return 1; |
| } |
| return 0; |
| #endif /* HAVE_DEV_PTS_AND_PTC */ |
| #endif /* HAVE_DEV_PTMX */ |
| #endif /* HAVE__GETPTY */ |
| #endif /* HAVE_OPENPTY */ |
| } |
| |
| /* Releases the tty. Its ownership is returned to root, and permissions to 0666. */ |
| |
| void |
| pty_release(const char *ttyname) |
| { |
| if ((chown(ttyname, (uid_t) 0, (gid_t) 0) < 0) && (errno != ENOENT)) |
| error("chown %.100s 0 0 failed: %.100s", ttyname, strerror(errno)); |
| if ((chmod(ttyname, (mode_t) 0666) < 0) && (errno != ENOENT)) |
| error("chmod %.100s 0666 failed: %.100s", ttyname, strerror(errno)); |
| } |
| |
| /* Makes the tty the processes controlling tty and sets it to sane modes. */ |
| |
| void |
| pty_make_controlling_tty(int *ttyfd, const char *ttyname) |
| { |
| int fd; |
| |
| /* First disconnect from the old controlling tty. */ |
| #ifdef TIOCNOTTY |
| fd = open("/dev/tty", O_RDWR | O_NOCTTY); |
| if (fd >= 0) { |
| (void) ioctl(fd, TIOCNOTTY, NULL); |
| close(fd); |
| } |
| #endif /* TIOCNOTTY */ |
| if (setsid() < 0) |
| error("setsid: %.100s", strerror(errno)); |
| |
| /* |
| * Verify that we are successfully disconnected from the controlling |
| * tty. |
| */ |
| fd = open("/dev/tty", O_RDWR | O_NOCTTY); |
| if (fd >= 0) { |
| error("Failed to disconnect from controlling tty."); |
| close(fd); |
| } |
| /* Make it our controlling tty. */ |
| #ifdef TIOCSCTTY |
| debug("Setting controlling tty using TIOCSCTTY."); |
| /* |
| * We ignore errors from this, because HPSUX defines TIOCSCTTY, but |
| * returns EINVAL with these arguments, and there is absolutely no |
| * documentation. |
| */ |
| ioctl(*ttyfd, TIOCSCTTY, NULL); |
| #endif /* TIOCSCTTY */ |
| fd = open(ttyname, O_RDWR); |
| if (fd < 0) |
| error("%.100s: %.100s", ttyname, strerror(errno)); |
| else |
| close(fd); |
| |
| /* Verify that we now have a controlling tty. */ |
| fd = open("/dev/tty", O_WRONLY); |
| if (fd < 0) |
| error("open /dev/tty failed - could not set controlling tty: %.100s", |
| strerror(errno)); |
| else { |
| close(fd); |
| } |
| } |
| |
| /* Changes the window size associated with the pty. */ |
| |
| void |
| pty_change_window_size(int ptyfd, int row, int col, |
| int xpixel, int ypixel) |
| { |
| struct winsize w; |
| w.ws_row = row; |
| w.ws_col = col; |
| w.ws_xpixel = xpixel; |
| w.ws_ypixel = ypixel; |
| (void) ioctl(ptyfd, TIOCSWINSZ, &w); |
| } |
| |
| void |
| pty_setowner(struct passwd *pw, const char *ttyname) |
| { |
| struct group *grp; |
| gid_t gid; |
| mode_t mode; |
| |
| /* Determine the group to make the owner of the tty. */ |
| grp = getgrnam("tty"); |
| if (grp) { |
| gid = grp->gr_gid; |
| mode = S_IRUSR | S_IWUSR | S_IWGRP; |
| } else { |
| gid = pw->pw_gid; |
| mode = S_IRUSR | S_IWUSR | S_IWGRP | S_IWOTH; |
| } |
| |
| /* Change ownership of the tty. */ |
| if (chown(ttyname, pw->pw_uid, gid) < 0) |
| fatal("chown(%.100s, %d, %d) failed: %.100s", |
| ttyname, pw->pw_uid, gid, strerror(errno)); |
| if (chmod(ttyname, mode) < 0) |
| fatal("chmod(%.100s, 0%o) failed: %.100s", |
| ttyname, mode, strerror(errno)); |
| } |