platform_bionic/tests/sys_xattr_test.cpp
Nick Kralevich 2825f10b7f libc: Add O_PATH support for fgetxattr / fsetxattr
Support O_PATH file descriptors when handling fgetxattr and fsetxattr.
This avoids requiring file read access to pull extended attributes.

This is needed to support O_PATH file descriptors when calling
SELinux's fgetfilecon() call. In particular, this allows the querying
and setting of SELinux file context by using something like the following
code:

  int dirfd = open("/path/to/dir", O_DIRECTORY);
  int fd = openat(dirfd, "file", O_PATH | O_NOFOLLOW);
  char *context;
  fgetfilecon(fd, &context);

This change was motivated by a comment in
https://android-review.googlesource.com/#/c/152680/1/toys/posix/ls.c

Change-Id: Ic0cdf9f9dd0e35a63b44a4c4a08400020041eddf
2015-06-01 15:51:56 -07:00

100 lines
2.7 KiB
C++

/*
* Copyright (C) 2015 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <gtest/gtest.h>
#include <sys/types.h>
#include <sys/xattr.h>
#include "TemporaryFile.h"
TEST(sys_xattr, setxattr) {
TemporaryFile tf;
char buf[10];
ASSERT_EQ(0, setxattr(tf.filename, "user.foo", "bar", 4, 0));
ASSERT_EQ(4, getxattr(tf.filename, "user.foo", buf, sizeof(buf)));
ASSERT_STREQ("bar", buf);
buf[0] = '\0';
ASSERT_EQ(4, lgetxattr(tf.filename, "user.foo", buf, sizeof(buf)));
ASSERT_STREQ("bar", buf);
}
TEST(sys_xattr, fsetxattr) {
TemporaryFile tf;
char buf[10];
ASSERT_EQ(0, fsetxattr(tf.fd, "user.foo", "bar", 4, 0));
ASSERT_EQ(4, fgetxattr(tf.fd, "user.foo", buf, sizeof(buf)));
ASSERT_STREQ("bar", buf);
}
TEST(sys_xattr, fsetxattr_zerobuf) {
TemporaryFile tf;
char buf[10];
ASSERT_EQ(0, fsetxattr(tf.fd, "user.foo", "", 0, 0));
ASSERT_EQ(0, fgetxattr(tf.fd, "user.foo", buf, sizeof(buf)));
}
TEST(sys_xattr, fsetxattr_toosmallbuf) {
TemporaryFile tf;
char buf[10];
ASSERT_EQ(0, fsetxattr(tf.fd, "user.foo", "01234567890123456789", 21, 0));
ASSERT_EQ(-1, fgetxattr(tf.fd, "user.foo", buf, sizeof(buf)));
ASSERT_EQ(ERANGE, errno);
}
TEST(sys_xattr, fsetxattr_invalidfd) {
char buf[10];
errno = 0;
ASSERT_EQ(-1, fsetxattr(65535, "user.foo", "0123", 5, 0));
ASSERT_EQ(EBADF, errno);
errno = 0;
ASSERT_EQ(-1, fgetxattr(65535, "user.foo", buf, sizeof(buf)));
ASSERT_EQ(EBADF, errno);
}
TEST(sys_xattr, fsetxattr_with_opath) {
TemporaryFile tf;
int fd = open(tf.filename, O_PATH);
ASSERT_NE(-1, fd);
int res = fsetxattr(fd, "user.foo", "bar", 4, 0);
#if defined(__BIONIC__)
char buf[10];
ASSERT_EQ(0, res);
ASSERT_EQ(4, fgetxattr(fd, "user.foo", buf, sizeof(buf)));
ASSERT_STREQ("bar", buf);
#else
ASSERT_EQ(-1, res);
ASSERT_EQ(EBADF, errno);
#endif
}
TEST(sys_xattr, fsetxattr_with_opath_toosmall) {
TemporaryFile tf;
int fd = open(tf.filename, O_PATH);
ASSERT_NE(-1, fd);
int res = fsetxattr(fd, "user.foo", "01234567890123456789", 21, 0);
#if defined(__BIONIC__)
char buf[10];
ASSERT_EQ(0, res);
ASSERT_EQ(-1, fgetxattr(fd, "user.foo", buf, sizeof(buf)));
ASSERT_EQ(ERANGE, errno);
#else
ASSERT_EQ(-1, res);
ASSERT_EQ(EBADF, errno);
#endif
}