From: Roland McGrath Date: Fri, 6 Jan 2006 12:14:26 +0000 (+0000) Subject: * io/fcntl.h [__USE_ATFILE] (AT_EACCESS): New macro. X-Git-Tag: upstream/2.30~15962 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=d15b99ac5af661dba1303f17a01f09aae7b6f5e7;p=external%2Fglibc.git * io/fcntl.h [__USE_ATFILE] (AT_EACCESS): New macro. * posix/unistd.h [__USE_ATFILE]: Declare faccessat. * io/faccessat.c: New file. * sysdeps/unix/sysv/linux/faccessat.c: New file. * io/Makefile (routines): Add faccessat. * io/Versions (libc: GLIBC_2.4): Likewise. * io/tst-faccessat.c: New file. * io/Makefile (tests): Add it. * io/sys/stat.h: Likewise. --- diff --git a/ChangeLog b/ChangeLog index 020576e..cc4a369 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,14 @@ 2006-01-06 Roland McGrath + * io/fcntl.h [__USE_ATFILE] (AT_EACCESS): New macro. + * posix/unistd.h [__USE_ATFILE]: Declare faccessat. + * io/faccessat.c: New file. + * sysdeps/unix/sysv/linux/faccessat.c: New file. + * io/Makefile (routines): Add faccessat. + * io/Versions (libc: GLIBC_2.4): Likewise. + * io/tst-faccessat.c: New file. + * io/Makefile (tests): Add it. + * scripts/check-local-headers.sh: Revert last change. * io/euidaccess.c: Add eaccess as an alias. @@ -67,6 +76,7 @@ * libio/stdio.h: Likewise. * posix/unistd.h: Likewise. * time/sys/time.h: Likewise. + * io/sys/stat.h: Likewise. * io/sys/stat.h [__USE_GNU]: Declare fchmodat. * io/fchmodat.c: New file. diff --git a/io/Makefile b/io/Makefile index b263a48..5e6d72e 100644 --- a/io/Makefile +++ b/io/Makefile @@ -35,10 +35,10 @@ routines := \ fxstatat fxstatat64 \ statfs fstatfs statfs64 fstatfs64 \ statvfs fstatvfs statvfs64 fstatvfs64 \ - umask chmod fchmod lchmod fchmodat \ + umask chmod fchmod lchmod fchmodat \ mkdir mkdirat \ open open64 openat openat64 close \ - read write lseek lseek64 access euidaccess \ + read write lseek lseek64 access euidaccess faccessat \ fcntl flock lockf lockf64 \ dup dup2 pipe \ creat creat64 \ @@ -64,7 +64,7 @@ test-srcs := ftwtest tests := test-utime test-stat test-stat2 test-lfs tst-getcwd \ tst-fcntl bug-ftw1 bug-ftw2 bug-ftw3 bug-ftw4 tst-statvfs \ tst-openat tst-unlinkat tst-fstatat tst-futimesat \ - tst-renameat tst-fchownat tst-fchmodat + tst-renameat tst-fchownat tst-fchmodat tst-faccessat distribute := ftwtest-sh diff --git a/io/Versions b/io/Versions index 823f8f2..16006a8 100644 --- a/io/Versions +++ b/io/Versions @@ -100,6 +100,7 @@ libc { GLIBC_2.4 { eaccess; + faccessat; fchmodat; fchownat; __fxstatat; __fxstatat64; diff --git a/io/faccessat.c b/io/faccessat.c new file mode 100644 index 0000000..8e41d37 --- /dev/null +++ b/io/faccessat.c @@ -0,0 +1,51 @@ +/* Test for access to file, relative to open directory. Stub version. + Copyright (C) 2006 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, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include +#include +#include +#include +#include + +int +faccessat (fd, file, type, flag) + int fd; + const char *file; + int type; + int flag; +{ + if (file == NULL || (flag & ~(AT_SYMLINK_NOFOLLOW | AT_EACCESS)) != 0 + || (type & ~(R_OK|W_OK|X_OK|F_OK)) != 0) + { + __set_errno (EINVAL); + return -1; + } + + if (fd < 0 && fd != AT_FDCWD) + { + __set_errno (EBADF); + return -1; + } + + __set_errno (ENOSYS); + return -1; +} +stub_warning (faccessat) + +#include diff --git a/io/fcntl.h b/io/fcntl.h index fd45933..e50afbb 100644 --- a/io/fcntl.h +++ b/io/fcntl.h @@ -63,6 +63,8 @@ __BEGIN_DECLS # define AT_SYMLINK_NOFOLLOW 0x100 /* Do not follow symbolic links. */ # define AT_REMOVEDIR 0x200 /* Remove directory instead of unlinking file. */ +# define AT_EACCESS 0x200 /* Test access permitted for + effective IDs, not real IDs. */ #endif /* Do the file control operation described by CMD on FD. diff --git a/io/sys/stat.h b/io/sys/stat.h index 93cd7d0..4cc0b42 100644 --- a/io/sys/stat.h +++ b/io/sys/stat.h @@ -228,7 +228,7 @@ extern int stat64 (__const char *__restrict __file, extern int fstat64 (int __fd, struct stat64 *__buf) __THROW __nonnull ((2)); #endif -#ifdef __USE_GNU +#ifdef __USE_ATFILE /* Similar to stat, get the attributes for FILE and put them in BUF. Relative path names are interpreted relative to FD unless FD is AT_FDCWD. */ @@ -293,12 +293,12 @@ extern int lchmod (__const char *__file, __mode_t __mode) extern int fchmod (int __fd, __mode_t __mode) __THROW; #endif -#ifdef __USE_GNU +#ifdef __USE_ATFILE /* Set file access permissions of FILE relative to the directory FD is open on. */ extern int fchmodat (int __fd, __const char *__file, __mode_t mode, int __flag) __THROW __nonnull ((2)) __wur; -#endif /* Use GNU. */ +#endif /* Use ATFILE. */ @@ -316,7 +316,7 @@ extern __mode_t getumask (void) __THROW; extern int mkdir (__const char *__path, __mode_t __mode) __THROW __nonnull ((1)); -#ifdef __USE_GNU +#ifdef __USE_ATFILE /* Like mkdir, create a new directory with permission bits MODE. But interpret relative PATH names relative to the directory associated with FD. */ @@ -332,7 +332,7 @@ extern int mknod (__const char *__path, __mode_t __mode, __dev_t __dev) __THROW __nonnull ((1)); #endif -#ifdef __USE_GNU +#ifdef __USE_ATFILE /* Like mknod, create a new device file with permission bits MODE and device number DEV. But interpret relative PATH names relative to the directory associated with FD. */ @@ -345,7 +345,7 @@ extern int mknodat (int __fd, __const char *__path, __mode_t __mode, extern int mkfifo (__const char *__path, __mode_t __mode) __THROW __nonnull ((1)); -#ifdef __USE_GNU +#ifdef __USE_ATFILE /* Like mkfifo, create a new FIFO with permission bits MODE. But interpret relative PATH names relative to the directory associated with FD. */ @@ -450,7 +450,7 @@ __NTH (fstat (int __fd, struct stat *__statbuf)) return __fxstat (_STAT_VER, __fd, __statbuf); } -# ifdef __USE_GNU +# ifdef __USE_ATFILE extern __inline__ int __NTH (fstatat (int __fd, __const char *__filename, struct stat *__statbuf, int __flag)) @@ -467,7 +467,7 @@ __NTH (mknod (__const char *__path, __mode_t __mode, __dev_t __dev)) } # endif -# ifdef __USE_GNU +# ifdef __USE_ATFILE extern __inline__ int __NTH (mknodat (int __fd, __const char *__path, __mode_t __mode, __dev_t __dev)) diff --git a/io/tst-faccessat.c b/io/tst-faccessat.c new file mode 100644 index 0000000..3bf7aed --- /dev/null +++ b/io/tst-faccessat.c @@ -0,0 +1,153 @@ +/* Test for faccessat function. */ + +#include +#include +#include +#include +#include +#include + + +static void prepare (void); +#define PREPARE(argc, argv) prepare () + +static int do_test (void); +#define TEST_FUNCTION do_test () + +#include "../test-skeleton.c" + +static int dir_fd; + +static void +prepare (void) +{ + size_t test_dir_len = strlen (test_dir); + static const char dir_name[] = "/tst-faccessat.XXXXXX"; + + size_t dirbuflen = test_dir_len + sizeof (dir_name); + char *dirbuf = malloc (dirbuflen); + if (dirbuf == NULL) + { + puts ("out of memory"); + exit (1); + } + + snprintf (dirbuf, dirbuflen, "%s%s", test_dir, dir_name); + if (mkdtemp (dirbuf) == NULL) + { + puts ("cannot create temporary directory"); + exit (1); + } + + add_temp_file (dirbuf); + + dir_fd = open (dirbuf, O_RDONLY | O_DIRECTORY); + if (dir_fd == -1) + { + puts ("cannot open directory"); + exit (1); + } +} + + +static int +do_test (void) +{ + /* fdopendir takes over the descriptor, make a copy. */ + int dupfd = dup (dir_fd); + if (dupfd == -1) + { + puts ("dup failed"); + return 1; + } + if (lseek (dupfd, 0, SEEK_SET) != 0) + { + puts ("1st lseek failed"); + return 1; + } + + /* The directory should be empty save the . and .. files. */ + DIR *dir = fdopendir (dupfd); + if (dir == NULL) + { + puts ("fdopendir failed"); + return 1; + } + struct dirent64 *d; + while ((d = readdir64 (dir)) != NULL) + if (strcmp (d->d_name, ".") != 0 && strcmp (d->d_name, "..") != 0) + { + printf ("temp directory contains file \"%s\"\n", d->d_name); + return 1; + } + closedir (dir); + + /* Try to create a file. */ + int fd = openat (dir_fd, "some-file", O_CREAT|O_RDWR|O_EXCL, 0666); + if (fd == -1) + { + if (errno == ENOSYS) + { + puts ("*at functions not supported"); + return 0; + } + + puts ("file creation failed"); + return 1; + } + write (fd, "hello", 5); + puts ("file created"); + + close (fd); + + int result = 0; + + if (faccessat (dir_fd, "some-file", F_OK, AT_EACCESS)) + { + printf ("faccessat F_OK: %m\n"); + result = 1; + } + if (faccessat (dir_fd, "some-file", W_OK, AT_EACCESS)) + { + printf ("faccessat W_OK: %m\n"); + result = 1; + } + + errno = 0; + if (faccessat (dir_fd, "some-file", X_OK, AT_EACCESS) == 0 + || errno != EACCES) + { + printf ("faccessat X_OK on nonexecutable: %m\n"); + result = 1; + } + + if (fchmodat (dir_fd, "some-file", 0400, 0) != 0) + { + printf ("fchownat failed: %m\n"); + return 1; + } + + if (faccessat (dir_fd, "some-file", R_OK, AT_EACCESS)) + { + printf ("faccessat R_OK: %m\n"); + result = 1; + } + + errno = 0; + if (faccessat (dir_fd, "some-file", W_OK, AT_EACCESS) == 0 + || errno != EACCES) + { + printf ("faccessat W_OK on unwritable file: %m\n"); + result = 1; + } + + if (unlinkat (dir_fd, "some-file", 0) != 0) + { + puts ("unlinkat failed"); + result = 1; + } + + close (dir_fd); + + return result; +} diff --git a/posix/unistd.h b/posix/unistd.h index 1bf843c..acb8f6f 100644 --- a/posix/unistd.h +++ b/posix/unistd.h @@ -266,6 +266,14 @@ extern int eaccess (__const char *__name, int __type) __THROW __nonnull ((1)); #endif +#ifdef __USE_ATFILE +/* Test for access to FILE relative to the directory FD is open on. + If AT_EACCESS is set in FLAG, then use effective IDs like `eaccess', + otherwise use real IDs like `access'. */ +extern int faccessat (int __fd, __const char *__file, int __type, int __flag) + __THROW __nonnull ((2)) __wur; +#endif /* Use GNU. */ + /* Values for the WHENCE argument to lseek. */ #ifndef _STDIO_H /* has the same definitions. */ diff --git a/sysdeps/unix/sysv/linux/faccessat.c b/sysdeps/unix/sysv/linux/faccessat.c new file mode 100644 index 0000000..80b3b24 --- /dev/null +++ b/sysdeps/unix/sysv/linux/faccessat.c @@ -0,0 +1,123 @@ +/* Test for access to file, relative to open directory. Linux version. + Copyright (C) 2006 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, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +int +faccessat (fd, file, mode, flag) + int fd; + const char *file; + int mode; + int flag; +{ + if (flag & ~(AT_SYMLINK_NOFOLLOW | AT_EACCESS)) + { + __set_errno (EINVAL); + return -1; + } + + char *buf = NULL; + + if (fd != AT_FDCWD && file[0] != '/') + { + size_t filelen = strlen (file); + static const char procfd[] = "/proc/self/fd/%d/%s"; + /* Buffer for the path name we are going to use. It consists of + - the string /proc/self/fd/ + - the file descriptor number + - the file name provided. + The final NUL is included in the sizeof. A bit of overhead + due to the format elements compensates for possible negative + numbers. */ + size_t buflen = sizeof (procfd) + sizeof (int) * 3 + filelen; + buf = alloca (buflen); + + __snprintf (buf, buflen, procfd, fd, file); + file = buf; + } + + if ((!(flag & AT_EACCESS) || ! __libc_enable_secure) +#ifndef __NR_laccess /* Linux so far has no laccess syscall. */ + && !(flag & AT_SYMLINK_NOFOLLOW) +#endif + ) + { + /* If we are not set-uid or set-gid, access does the same. */ + + int result; + INTERNAL_SYSCALL_DECL (err); + +#ifdef __NR_laccess + if (flag & AT_SYMLINK_NOFOLLOW) + result = INTERNAL_SYSCALL (laccess, err, 2, file, mode); + else +#endif + result = INTERNAL_SYSCALL (access, err, 2, file, mode); + + if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (result, err), 0)) + { + __atfct_seterrno (INTERNAL_SYSCALL_ERRNO (result, err), fd, buf); + result = -1; + } + + return result; + } + + struct stat64 stats; + if (fstatat64 (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; + + __set_errno (EACCES); + return -1; +}