diff options
Diffstat (limited to 'sysdeps/unix/grantpt.c')
-rw-r--r-- | sysdeps/unix/grantpt.c | 260 |
1 files changed, 0 insertions, 260 deletions
diff --git a/sysdeps/unix/grantpt.c b/sysdeps/unix/grantpt.c deleted file mode 100644 index a73020e69a..0000000000 --- a/sysdeps/unix/grantpt.c +++ /dev/null @@ -1,260 +0,0 @@ -/* Copyright (C) 1998-2017 Free Software Foundation, Inc. - This file is part of the GNU C Library. - Contributed by Zack Weinberg <zack@rabi.phys.columbia.edu>, 1998. - - The GNU C Library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public - License as published by the Free Software Foundation; either - version 2.1 of the License, or (at your option) any later version. - - The GNU C Library is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public - License along with the GNU C Library; if not, see - <http://www.gnu.org/licenses/>. */ - -#include <assert.h> -#include <errno.h> -#include <fcntl.h> -#include <grp.h> -#include <limits.h> -#include <stdlib.h> -#include <string.h> -#include <sys/resource.h> -#include <sys/stat.h> -#include <sys/types.h> -#include <sys/wait.h> -#include <unistd.h> - -#include "pty-private.h" - - -/* Return the result of ptsname_r in the buffer pointed to by PTS, - which should be of length BUF_LEN. If it is too long to fit in - this buffer, a sufficiently long buffer is allocated using malloc, - and returned in PTS. 0 is returned upon success, -1 otherwise. */ -static int -pts_name (int fd, char **pts, size_t buf_len, struct stat64 *stp) -{ - int rv; - char *buf = *pts; - - for (;;) - { - char *new_buf; - - if (buf_len) - { - rv = __ptsname_internal (fd, buf, buf_len, stp); - if (rv != 0) - { - if (rv == ENOTTY) - /* ptsname_r returns with ENOTTY to indicate - a descriptor not referring to a pty master. - For this condition, grantpt must return EINVAL. */ - rv = EINVAL; - errno = rv; /* Not necessarily set by __ptsname_r. */ - break; - } - - if (memchr (buf, '\0', buf_len)) - /* We succeeded and the returned name fit in the buffer. */ - break; - - /* Try again with a longer buffer. */ - buf_len += buf_len; /* Double it */ - } - else - /* No initial buffer; start out by mallocing one. */ - buf_len = 128; /* First time guess. */ - - if (buf != *pts) - /* We've already malloced another buffer at least once. */ - new_buf = (char *) realloc (buf, buf_len); - else - new_buf = (char *) malloc (buf_len); - if (! new_buf) - { - rv = -1; - __set_errno (ENOMEM); - break; - } - buf = new_buf; - } - - if (rv == 0) - *pts = buf; /* Return buffer to the user. */ - else if (buf != *pts) - free (buf); /* Free what we malloced when returning an error. */ - - return rv; -} - -/* Change the ownership and access permission of the slave pseudo - terminal associated with the master pseudo terminal specified - by FD. */ -int -grantpt (int fd) -{ - int retval = -1; -#ifdef PATH_MAX - char _buf[PATH_MAX]; -#else - char _buf[512]; -#endif - char *buf = _buf; - struct stat64 st; - - if (__glibc_unlikely (pts_name (fd, &buf, sizeof (_buf), &st))) - { - int save_errno = errno; - - /* Check, if the file descriptor is valid. pts_name returns the - wrong errno number, so we cannot use that. */ - if (__libc_fcntl (fd, F_GETFD) == -1 && errno == EBADF) - return -1; - - /* If the filedescriptor is no TTY, grantpt has to set errno - to EINVAL. */ - if (save_errno == ENOTTY) - __set_errno (EINVAL); - else - __set_errno (save_errno); - - return -1; - } - - /* Make sure that we own the device. */ - uid_t uid = __getuid (); - if (st.st_uid != uid) - { - if (__chown (buf, uid, st.st_gid) < 0) - goto helper; - } - - static int tty_gid = -1; - if (__glibc_unlikely (tty_gid == -1)) - { - char *grtmpbuf; - struct group grbuf; - size_t grbuflen = __sysconf (_SC_GETGR_R_SIZE_MAX); - struct group *p; - - /* Get the group ID of the special `tty' group. */ - if (grbuflen == (size_t) -1L) - /* `sysconf' does not support _SC_GETGR_R_SIZE_MAX. - Try a moderate value. */ - grbuflen = 1024; - grtmpbuf = (char *) __alloca (grbuflen); - __getgrnam_r (TTY_GROUP, &grbuf, grtmpbuf, grbuflen, &p); - if (p != NULL) - tty_gid = p->gr_gid; - } - gid_t gid = tty_gid == -1 ? __getgid () : tty_gid; - -#if HAVE_PT_CHOWN - /* Make sure the group of the device is that special group. */ - if (st.st_gid != gid) - { - if (__chown (buf, uid, gid) < 0) - goto helper; - } - - /* Make sure the permission mode is set to readable and writable by - the owner, and writable by the group. */ - mode_t mode = S_IRUSR|S_IWUSR|S_IWGRP; -#else - /* When built without pt_chown, we have delegated the creation of the - pty node with the right group and permission mode to the kernel, and - non-root users are unlikely to be able to change it. Therefore let's - consider that POSIX enforcement is the responsibility of the whole - system and not only the GNU libc. Thus accept different group or - permission mode. */ - - /* Make sure the permission is set to readable and writable by the - owner. For security reasons, make it writable by the group only - when originally writable and when the group of the device is that - special group. */ - mode_t mode = S_IRUSR|S_IWUSR| - ((st.st_gid == gid) ? (st.st_mode & S_IWGRP) : 0); -#endif - - if ((st.st_mode & ACCESSPERMS) != mode) - { - if (__chmod (buf, mode) < 0) - goto helper; - } - - retval = 0; - goto cleanup; - - /* We have to use the helper program if it is available. */ - helper:; - -#if HAVE_PT_CHOWN - pid_t pid = __fork (); - if (pid == -1) - goto cleanup; - else if (pid == 0) - { - /* Disable core dumps. */ - struct rlimit rl = { 0, 0 }; - __setrlimit (RLIMIT_CORE, &rl); - - /* We pass the master pseudo terminal as file descriptor PTY_FILENO. */ - if (fd != PTY_FILENO) - if (__dup2 (fd, PTY_FILENO) < 0) - _exit (FAIL_EBADF); - -# ifdef CLOSE_ALL_FDS - CLOSE_ALL_FDS (); -# endif - - execle (_PATH_PT_CHOWN, __basename (_PATH_PT_CHOWN), NULL, NULL); - _exit (FAIL_EXEC); - } - else - { - int w; - - if (__waitpid (pid, &w, 0) == -1) - goto cleanup; - if (!WIFEXITED (w)) - __set_errno (ENOEXEC); - else - switch (WEXITSTATUS (w)) - { - case 0: - retval = 0; - break; - case FAIL_EBADF: - __set_errno (EBADF); - break; - case FAIL_EINVAL: - __set_errno (EINVAL); - break; - case FAIL_EACCES: - __set_errno (EACCES); - break; - case FAIL_EXEC: - __set_errno (ENOEXEC); - break; - case FAIL_ENOMEM: - __set_errno (ENOMEM); - break; - - default: - assert(! "grantpt: internal error: invalid exit code from pt_chown"); - } - } -#endif - - cleanup: - if (buf != _buf) - free (buf); - - return retval; -} |