diff options
Diffstat (limited to 'src/regress/lib/libc/explicit_bzero')
| -rw-r--r-- | src/regress/lib/libc/explicit_bzero/Makefile | 5 | ||||
| -rw-r--r-- | src/regress/lib/libc/explicit_bzero/explicit_bzero.c | 225 |
2 files changed, 0 insertions, 230 deletions
diff --git a/src/regress/lib/libc/explicit_bzero/Makefile b/src/regress/lib/libc/explicit_bzero/Makefile deleted file mode 100644 index cd514a43a1..0000000000 --- a/src/regress/lib/libc/explicit_bzero/Makefile +++ /dev/null | |||
| @@ -1,5 +0,0 @@ | |||
| 1 | # $OpenBSD: Makefile,v 1.1 2014/06/12 22:01:55 matthew Exp $ | ||
| 2 | |||
| 3 | PROG= explicit_bzero | ||
| 4 | |||
| 5 | .include <bsd.regress.mk> | ||
diff --git a/src/regress/lib/libc/explicit_bzero/explicit_bzero.c b/src/regress/lib/libc/explicit_bzero/explicit_bzero.c deleted file mode 100644 index 496bafb208..0000000000 --- a/src/regress/lib/libc/explicit_bzero/explicit_bzero.c +++ /dev/null | |||
| @@ -1,225 +0,0 @@ | |||
| 1 | /* $OpenBSD: explicit_bzero.c,v 1.9 2022/02/10 08:39:32 tb Exp $ */ | ||
| 2 | /* | ||
| 3 | * Copyright (c) 2014 Google Inc. | ||
| 4 | * | ||
| 5 | * Permission to use, copy, modify, and distribute this software for any | ||
| 6 | * purpose with or without fee is hereby granted, provided that the above | ||
| 7 | * copyright notice and this permission notice appear in all copies. | ||
| 8 | * | ||
| 9 | * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES | ||
| 10 | * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF | ||
| 11 | * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR | ||
| 12 | * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES | ||
| 13 | * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN | ||
| 14 | * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF | ||
| 15 | * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. | ||
| 16 | */ | ||
| 17 | |||
| 18 | #include <assert.h> | ||
| 19 | #include <errno.h> | ||
| 20 | #include <signal.h> | ||
| 21 | #include <stdlib.h> | ||
| 22 | #include <string.h> | ||
| 23 | #include <unistd.h> | ||
| 24 | |||
| 25 | #define ASSERT_EQ(a, b) assert((a) == (b)) | ||
| 26 | #define ASSERT_NE(a, b) assert((a) != (b)) | ||
| 27 | #define ASSERT_GE(a, b) assert((a) >= (b)) | ||
| 28 | |||
| 29 | #if defined(__has_feature) | ||
| 30 | #if __has_feature(address_sanitizer) | ||
| 31 | #define __SANITIZE_ADDRESS__ | ||
| 32 | #endif | ||
| 33 | #endif | ||
| 34 | #ifdef __SANITIZE_ADDRESS__ | ||
| 35 | #define ATTRIBUTE_NO_SANITIZE_ADDRESS __attribute__((no_sanitize_address)) | ||
| 36 | #else | ||
| 37 | #define ATTRIBUTE_NO_SANITIZE_ADDRESS | ||
| 38 | #endif | ||
| 39 | |||
| 40 | /* 128 bits of random data. */ | ||
| 41 | static const char secret[16] = { | ||
| 42 | 0xa0, 0x6c, 0x0c, 0x81, 0xba, 0xd8, 0x5b, 0x0c, | ||
| 43 | 0xb0, 0xd6, 0xd4, 0xe3, 0xeb, 0x52, 0x5f, 0x96, | ||
| 44 | }; | ||
| 45 | |||
| 46 | enum { | ||
| 47 | SECRETCOUNT = 64, | ||
| 48 | SECRETBYTES = SECRETCOUNT * sizeof(secret) | ||
| 49 | }; | ||
| 50 | |||
| 51 | /* | ||
| 52 | * As of glibc 2.34, when _GNU_SOURCE is defined, SIGSTKSZ is no longer | ||
| 53 | * constant on Linux. SIGSTKSZ is redefined to sysconf (_SC_SIGSTKSZ). | ||
| 54 | */ | ||
| 55 | static char *altstack; | ||
| 56 | #define ALTSTACK_SIZE (SIGSTKSZ + SECRETBYTES) | ||
| 57 | |||
| 58 | static void | ||
| 59 | setup_stack(void) | ||
| 60 | { | ||
| 61 | altstack = calloc(1, ALTSTACK_SIZE); | ||
| 62 | ASSERT_NE(NULL, altstack); | ||
| 63 | |||
| 64 | const stack_t sigstk = { | ||
| 65 | .ss_sp = altstack, | ||
| 66 | .ss_size = ALTSTACK_SIZE | ||
| 67 | }; | ||
| 68 | |||
| 69 | ASSERT_EQ(0, sigaltstack(&sigstk, NULL)); | ||
| 70 | } | ||
| 71 | |||
| 72 | static void | ||
| 73 | cleanup_stack(void) | ||
| 74 | { | ||
| 75 | free(altstack); | ||
| 76 | } | ||
| 77 | |||
| 78 | static void | ||
| 79 | assert_on_stack(void) | ||
| 80 | { | ||
| 81 | stack_t cursigstk; | ||
| 82 | ASSERT_EQ(0, sigaltstack(NULL, &cursigstk)); | ||
| 83 | ASSERT_EQ(SS_ONSTACK, cursigstk.ss_flags & (SS_DISABLE|SS_ONSTACK)); | ||
| 84 | } | ||
| 85 | |||
| 86 | static void | ||
| 87 | call_on_stack(void (*fn)(int)) | ||
| 88 | { | ||
| 89 | /* | ||
| 90 | * This is a bit more complicated than strictly necessary, but | ||
| 91 | * it ensures we don't have any flaky test failures due to | ||
| 92 | * inherited signal masks/actions/etc. | ||
| 93 | * | ||
| 94 | * On systems where SA_ONSTACK is not supported, this could | ||
| 95 | * alternatively be implemented using makecontext() or | ||
| 96 | * pthread_attr_setstack(). | ||
| 97 | */ | ||
| 98 | |||
| 99 | const struct sigaction sigact = { | ||
| 100 | .sa_handler = fn, | ||
| 101 | .sa_flags = SA_ONSTACK, | ||
| 102 | }; | ||
| 103 | struct sigaction oldsigact; | ||
| 104 | sigset_t sigset, oldsigset; | ||
| 105 | |||
| 106 | /* First, block all signals. */ | ||
| 107 | ASSERT_EQ(0, sigemptyset(&sigset)); | ||
| 108 | ASSERT_EQ(0, sigfillset(&sigset)); | ||
| 109 | ASSERT_EQ(0, sigprocmask(SIG_BLOCK, &sigset, &oldsigset)); | ||
| 110 | |||
| 111 | /* Next setup the signal handler for SIGUSR1. */ | ||
| 112 | ASSERT_EQ(0, sigaction(SIGUSR1, &sigact, &oldsigact)); | ||
| 113 | |||
| 114 | /* Raise SIGUSR1 and momentarily unblock it to run the handler. */ | ||
| 115 | ASSERT_EQ(0, raise(SIGUSR1)); | ||
| 116 | ASSERT_EQ(0, sigdelset(&sigset, SIGUSR1)); | ||
| 117 | ASSERT_EQ(-1, sigsuspend(&sigset)); | ||
| 118 | ASSERT_EQ(EINTR, errno); | ||
| 119 | |||
| 120 | /* Restore the original signal action, stack, and mask. */ | ||
| 121 | ASSERT_EQ(0, sigaction(SIGUSR1, &oldsigact, NULL)); | ||
| 122 | ASSERT_EQ(0, sigprocmask(SIG_SETMASK, &oldsigset, NULL)); | ||
| 123 | } | ||
| 124 | |||
| 125 | static void | ||
| 126 | populate_secret(char *buf, size_t len) | ||
| 127 | { | ||
| 128 | int i, fds[2]; | ||
| 129 | ASSERT_EQ(0, pipe(fds)); | ||
| 130 | |||
| 131 | for (i = 0; i < SECRETCOUNT; i++) | ||
| 132 | ASSERT_EQ(sizeof(secret), write(fds[1], secret, sizeof(secret))); | ||
| 133 | ASSERT_EQ(0, close(fds[1])); | ||
| 134 | |||
| 135 | ASSERT_EQ(len, read(fds[0], buf, len)); | ||
| 136 | ASSERT_EQ(0, close(fds[0])); | ||
| 137 | } | ||
| 138 | |||
| 139 | static int | ||
| 140 | count_secrets(const char *buf) | ||
| 141 | { | ||
| 142 | int res = 0; | ||
| 143 | size_t i; | ||
| 144 | for (i = 0; i < SECRETCOUNT; i++) { | ||
| 145 | if (memcmp(buf + i * sizeof(secret), secret, | ||
| 146 | sizeof(secret)) == 0) | ||
| 147 | res += 1; | ||
| 148 | } | ||
| 149 | return (res); | ||
| 150 | } | ||
| 151 | |||
| 152 | ATTRIBUTE_NO_SANITIZE_ADDRESS static char * | ||
| 153 | test_without_bzero(void) | ||
| 154 | { | ||
| 155 | char buf[SECRETBYTES]; | ||
| 156 | assert_on_stack(); | ||
| 157 | populate_secret(buf, sizeof(buf)); | ||
| 158 | char *res = memmem(altstack, ALTSTACK_SIZE, buf, sizeof(buf)); | ||
| 159 | ASSERT_NE(NULL, res); | ||
| 160 | return (res); | ||
| 161 | } | ||
| 162 | |||
| 163 | ATTRIBUTE_NO_SANITIZE_ADDRESS static char * | ||
| 164 | test_with_bzero(void) | ||
| 165 | { | ||
| 166 | char buf[SECRETBYTES]; | ||
| 167 | assert_on_stack(); | ||
| 168 | populate_secret(buf, sizeof(buf)); | ||
| 169 | char *res = memmem(altstack, ALTSTACK_SIZE, buf, sizeof(buf)); | ||
| 170 | ASSERT_NE(NULL, res); | ||
| 171 | explicit_bzero(buf, sizeof(buf)); | ||
| 172 | return (res); | ||
| 173 | } | ||
| 174 | |||
| 175 | static void | ||
| 176 | do_test_without_bzero(int signo) | ||
| 177 | { | ||
| 178 | char *buf = test_without_bzero(); | ||
| 179 | ASSERT_GE(count_secrets(buf), 1); | ||
| 180 | } | ||
| 181 | |||
| 182 | static void | ||
| 183 | do_test_with_bzero(int signo) | ||
| 184 | { | ||
| 185 | char *buf = test_with_bzero(); | ||
| 186 | ASSERT_EQ(count_secrets(buf), 0); | ||
| 187 | } | ||
| 188 | |||
| 189 | int | ||
| 190 | main(void) | ||
| 191 | { | ||
| 192 | setup_stack(); | ||
| 193 | |||
| 194 | /* | ||
| 195 | * Solaris and OS X clobber the signal stack after returning to the | ||
| 196 | * normal stack, so we need to inspect altstack while we're still | ||
| 197 | * running on it. Unfortunately, this means we risk clobbering the | ||
| 198 | * buffer ourselves. | ||
| 199 | * | ||
| 200 | * To minimize this risk, test_with{,out}_bzero() are responsible for | ||
| 201 | * locating the offset of their buf variable within altstack, and | ||
| 202 | * and returning that address. Then we can simply memcmp() repeatedly | ||
| 203 | * to count how many instances of secret we found. | ||
| 204 | */ | ||
| 205 | |||
| 206 | /* | ||
| 207 | * First, test that if we *don't* call explicit_bzero, that we | ||
| 208 | * *are* able to find at least one instance of the secret data still | ||
| 209 | * on the stack. This sanity checks that call_on_stack() and | ||
| 210 | * populate_secret() work as intended. | ||
| 211 | */ | ||
| 212 | memset(altstack, 0, ALTSTACK_SIZE); | ||
| 213 | call_on_stack(do_test_without_bzero); | ||
| 214 | |||
| 215 | /* | ||
| 216 | * Now test with a call to explicit_bzero() and check that we | ||
| 217 | * *don't* find any instances of the secret data. | ||
| 218 | */ | ||
| 219 | memset(altstack, 0, ALTSTACK_SIZE); | ||
| 220 | call_on_stack(do_test_with_bzero); | ||
| 221 | |||
| 222 | cleanup_stack(); | ||
| 223 | |||
| 224 | return (0); | ||
| 225 | } | ||
