1 /*
2 * Copyright (C) 2013 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include <sys/auxv.h>
18
19 #include <errno.h>
20 #include <sys/cdefs.h>
21 #include <sys/utsname.h>
22 #include <gtest/gtest.h>
23
TEST(getauxval,expected_values)24 TEST(getauxval, expected_values) {
25 ASSERT_EQ(0UL, getauxval(AT_SECURE));
26 ASSERT_EQ(getuid(), getauxval(AT_UID));
27 ASSERT_EQ(geteuid(), getauxval(AT_EUID));
28 ASSERT_EQ(getgid(), getauxval(AT_GID));
29 ASSERT_EQ(getegid(), getauxval(AT_EGID));
30 ASSERT_EQ(static_cast<unsigned long>(getpagesize()), getauxval(AT_PAGESZ));
31
32 ASSERT_NE(0UL, getauxval(AT_PHDR));
33 ASSERT_NE(0UL, getauxval(AT_PHNUM));
34 ASSERT_NE(0UL, getauxval(AT_ENTRY));
35 ASSERT_NE(0UL, getauxval(AT_PAGESZ));
36 }
37
TEST(getauxval,unexpected_values)38 TEST(getauxval, unexpected_values) {
39 errno = 0;
40 ASSERT_EQ(0UL, getauxval(0xdeadbeef));
41 ASSERT_EQ(ENOENT, errno);
42 }
43
TEST(getauxval,arm_has_AT_HWCAP2)44 TEST(getauxval, arm_has_AT_HWCAP2) {
45 #if defined(__arm__)
46 // There are no known 32-bit processors that implement any of these instructions, so rather
47 // than require that OEMs backport kernel patches, let's just ignore old hardware. Strictly
48 // speaking this would be fooled by someone choosing to ship a 32-bit kernel on 64-bit hardware,
49 // but that doesn't seem very likely in 2016.
50 utsname u;
51 ASSERT_EQ(0, uname(&u));
52 if (strcmp(u.machine, "aarch64") == 0) {
53 // If this test fails, apps that use getauxval to decide at runtime whether crypto hardware is
54 // available will incorrectly assume that it isn't, and will have really bad performance.
55 // If this test fails, ensure that you've enabled COMPAT_BINFMT_ELF in your kernel configuration.
56 // Note that 0 ("I don't support any of these things") is a legitimate response --- we need
57 // to check errno to see whether we got a "true" 0 or a "not found" 0.
58 errno = 0;
59 getauxval(AT_HWCAP2);
60 ASSERT_EQ(0, errno) << "64-bit kernel not reporting AT_HWCAP2 to 32-bit ARM process";
61 return;
62 }
63 #endif
64 GTEST_SKIP() << "This test is only meaningful for 32-bit ARM code on 64-bit devices";
65 }
66