diff options
Diffstat (limited to 'REORG.TODO/sysdeps/unix/sysv/linux/faccessat.c')
-rw-r--r-- | REORG.TODO/sysdeps/unix/sysv/linux/faccessat.c | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/unix/sysv/linux/faccessat.c b/REORG.TODO/sysdeps/unix/sysv/linux/faccessat.c new file mode 100644 index 0000000000..5aecb10840 --- /dev/null +++ b/REORG.TODO/sysdeps/unix/sysv/linux/faccessat.c @@ -0,0 +1,71 @@ +/* Test for access to file, relative to open directory. Linux version. + Copyright (C) 2006-2017 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + 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 <errno.h> +#include <fcntl.h> +#include <stddef.h> +#include <stdio.h> +#include <string.h> +#include <unistd.h> +#include <sys/types.h> +#include <alloca.h> +#include <sysdep.h> + + +int +faccessat (int fd, const char *file, int mode, int flag) +{ + if (flag & ~(AT_SYMLINK_NOFOLLOW | AT_EACCESS)) + return INLINE_SYSCALL_ERROR_RETURN_VALUE (EINVAL); + + if ((flag == 0 || ((flag & ~AT_EACCESS) == 0 && ! __libc_enable_secure))) + return INLINE_SYSCALL (faccessat, 3, fd, file, mode); + + struct stat64 stats; + if (__fxstatat64 (_STAT_VER, fd, file, &stats, flag & AT_SYMLINK_NOFOLLOW)) + return -1; + + mode &= (X_OK | W_OK | R_OK); /* Clear any bogus bits. */ +#if R_OK != S_IROTH || W_OK != S_IWOTH || X_OK != S_IXOTH +# error Oops, portability assumptions incorrect. +#endif + + if (mode == F_OK) + return 0; /* The file exists. */ + + uid_t uid = (flag & AT_EACCESS) ? __geteuid () : __getuid (); + + /* The super-user can read and write any file, and execute any file + that anyone can execute. */ + if (uid == 0 && ((mode & X_OK) == 0 + || (stats.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH)))) + return 0; + + int granted = (uid == stats.st_uid + ? (unsigned int) (stats.st_mode & (mode << 6)) >> 6 + : (stats.st_gid == ((flag & AT_EACCESS) + ? __getegid () : __getgid ()) + || __group_member (stats.st_gid)) + ? (unsigned int) (stats.st_mode & (mode << 3)) >> 3 + : (stats.st_mode & mode)); + + if (granted == mode) + return 0; + + return INLINE_SYSCALL_ERROR_RETURN_VALUE (EACCES); +} |