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Diffstat (limited to 'external/unbound/compat/getentropy_linux.c')
-rw-r--r--external/unbound/compat/getentropy_linux.c566
1 files changed, 0 insertions, 566 deletions
diff --git a/external/unbound/compat/getentropy_linux.c b/external/unbound/compat/getentropy_linux.c
deleted file mode 100644
index cae18e03b..000000000
--- a/external/unbound/compat/getentropy_linux.c
+++ /dev/null
@@ -1,566 +0,0 @@
-/* $OpenBSD: getentropy_linux.c,v 1.20 2014/07/12 15:43:49 beck Exp $ */
-
-/*
- * Copyright (c) 2014 Theo de Raadt <deraadt@openbsd.org>
- * Copyright (c) 2014 Bob Beck <beck@obtuse.com>
- *
- * Permission to use, copy, modify, and distribute this software for any
- * purpose with or without fee is hereby granted, provided that the above
- * copyright notice and this permission notice appear in all copies.
- *
- * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
- * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
- * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
- * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
- * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
- * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
- * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
- */
-#include "config.h"
-
-/*
-#define _POSIX_C_SOURCE 199309L
-#define _GNU_SOURCE 1
-*/
-#include <sys/types.h>
-#include <sys/param.h>
-#include <sys/ioctl.h>
-#include <sys/resource.h>
-#include <sys/syscall.h>
-#ifdef HAVE_SYS_SYSCTL_H
-#include <sys/sysctl.h>
-#endif
-#ifdef __ANDROID__
-#include <sys/vfs.h>
-#define statvfs statfs
-#define fstatvfs fstatfs
-#else
-#include <sys/statvfs.h>
-#endif
-#include <sys/socket.h>
-#include <sys/mount.h>
-#include <sys/mman.h>
-#include <sys/stat.h>
-#include <sys/time.h>
-#include <stdlib.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <termios.h>
-#include <fcntl.h>
-#include <signal.h>
-#include <string.h>
-#include <errno.h>
-#include <unistd.h>
-#include <time.h>
-
-#if defined(HAVE_SSL)
-#include <openssl/sha.h>
-#elif defined(HAVE_NETTLE)
-#include <nettle/sha.h>
-#endif
-
-#include <linux/types.h>
-#include <linux/random.h>
-#include <linux/sysctl.h>
-#ifdef HAVE_GETAUXVAL
-#include <sys/auxv.h>
-#endif
-#include <sys/vfs.h>
-#ifndef MAP_ANON
-#define MAP_ANON MAP_ANONYMOUS
-#endif
-
-#define REPEAT 5
-#define min(a, b) (((a) < (b)) ? (a) : (b))
-
-#define HX(a, b) \
- do { \
- if ((a)) \
- HD(errno); \
- else \
- HD(b); \
- } while (0)
-
-#if defined(HAVE_SSL)
-#define CRYPTO_SHA512_CTX SHA512_CTX
-#define CRYPTO_SHA512_INIT(x) SHA512_Init(x)
-#define CRYPTO_SHA512_FINAL(r, c) SHA512_Final(r, c)
-#define HR(x, l) (SHA512_Update(&ctx, (char *)(x), (l)))
-#define HD(x) (SHA512_Update(&ctx, (char *)&(x), sizeof (x)))
-#define HF(x) (SHA512_Update(&ctx, (char *)&(x), sizeof (void*)))
-#elif defined(HAVE_NETTLE)
-#define CRYPTO_SHA512_CTX struct sha512_ctx
-#define CRYPTO_SHA512_INIT(x) sha512_init(x)
-#define CRYPTO_SHA512_FINAL(r, c) sha512_digest(c, SHA512_DIGEST_SIZE, r)
-#define HR(x, l) (sha512_update(&ctx, (l), (uint8_t *)(x)))
-#define HD(x) (sha512_update(&ctx, sizeof (x), (uint8_t *)&(x)))
-#define HF(x) (sha512_update(&ctx, sizeof (void*), (uint8_t *)&(x)))
-#endif
-
-int getentropy(void *buf, size_t len);
-
-#ifdef CAN_REFERENCE_MAIN
-extern int main(int, char *argv[]);
-#endif
-static int gotdata(char *buf, size_t len);
-#if defined(SYS_getrandom) && defined(__NR_getrandom)
-static int getentropy_getrandom(void *buf, size_t len);
-#endif
-static int getentropy_urandom(void *buf, size_t len);
-#ifdef SYS__sysctl
-static int getentropy_sysctl(void *buf, size_t len);
-#endif
-static int getentropy_fallback(void *buf, size_t len);
-
-int
-getentropy(void *buf, size_t len)
-{
- int ret = -1;
-
- if (len > 256) {
- errno = EIO;
- return -1;
- }
-
-#if defined(SYS_getrandom) && defined(__NR_getrandom)
- /*
- * Try descriptor-less getrandom()
- */
- ret = getentropy_getrandom(buf, len);
- if (ret != -1)
- return (ret);
- if (errno != ENOSYS)
- return (-1);
-#endif
-
- /*
- * Try to get entropy with /dev/urandom
- *
- * This can fail if the process is inside a chroot or if file
- * descriptors are exhausted.
- */
- ret = getentropy_urandom(buf, len);
- if (ret != -1)
- return (ret);
-
-#ifdef SYS__sysctl
- /*
- * Try to use sysctl CTL_KERN, KERN_RANDOM, RANDOM_UUID.
- * sysctl is a failsafe API, so it guarantees a result. This
- * should work inside a chroot, or when file descriptors are
- * exhausted.
- *
- * However this can fail if the Linux kernel removes support
- * for sysctl. Starting in 2007, there have been efforts to
- * deprecate the sysctl API/ABI, and push callers towards use
- * of the chroot-unavailable fd-using /proc mechanism --
- * essentially the same problems as /dev/urandom.
- *
- * Numerous setbacks have been encountered in their deprecation
- * schedule, so as of June 2014 the kernel ABI still exists on
- * most Linux architectures. The sysctl() stub in libc is missing
- * on some systems. There are also reports that some kernels
- * spew messages to the console.
- */
- ret = getentropy_sysctl(buf, len);
- if (ret != -1)
- return (ret);
-#endif /* SYS__sysctl */
-
- /*
- * Entropy collection via /dev/urandom and sysctl have failed.
- *
- * No other API exists for collecting entropy. See the large
- * comment block above.
- *
- * We have very few options:
- * - Even syslog_r is unsafe to call at this low level, so
- * there is no way to alert the user or program.
- * - Cannot call abort() because some systems have unsafe
- * corefiles.
- * - Could raise(SIGKILL) resulting in silent program termination.
- * - Return EIO, to hint that arc4random's stir function
- * should raise(SIGKILL)
- * - Do the best under the circumstances....
- *
- * This code path exists to bring light to the issue that Linux
- * does not provide a failsafe API for entropy collection.
- *
- * We hope this demonstrates that Linux should either retain their
- * sysctl ABI, or consider providing a new failsafe API which
- * works in a chroot or when file descriptors are exhausted.
- */
-#undef FAIL_INSTEAD_OF_TRYING_FALLBACK
-#ifdef FAIL_INSTEAD_OF_TRYING_FALLBACK
- raise(SIGKILL);
-#endif
- ret = getentropy_fallback(buf, len);
- if (ret != -1)
- return (ret);
-
- errno = EIO;
- return (ret);
-}
-
-/*
- * Basic sanity checking; wish we could do better.
- */
-static int
-gotdata(char *buf, size_t len)
-{
- char any_set = 0;
- size_t i;
-
- for (i = 0; i < len; ++i)
- any_set |= buf[i];
- if (any_set == 0)
- return -1;
- return 0;
-}
-
-#if defined(SYS_getrandom) && defined(__NR_getrandom)
-static int
-getentropy_getrandom(void *buf, size_t len)
-{
- int pre_errno = errno;
- int ret;
- if (len > 256)
- return (-1);
- do {
- ret = syscall(SYS_getrandom, buf, len, 0);
- } while (ret == -1 && errno == EINTR);
-
- if (ret != (int)len)
- return (-1);
- errno = pre_errno;
- return (0);
-}
-#endif
-
-static int
-getentropy_urandom(void *buf, size_t len)
-{
- struct stat st;
- size_t i;
- int fd, cnt, flags;
- int save_errno = errno;
-
-start:
-
- flags = O_RDONLY;
-#ifdef O_NOFOLLOW
- flags |= O_NOFOLLOW;
-#endif
-#ifdef O_CLOEXEC
- flags |= O_CLOEXEC;
-#endif
- fd = open("/dev/urandom", flags, 0);
- if (fd == -1) {
- if (errno == EINTR)
- goto start;
- goto nodevrandom;
- }
-#ifndef O_CLOEXEC
- fcntl(fd, F_SETFD, fcntl(fd, F_GETFD) | FD_CLOEXEC);
-#endif
-
- /* Lightly verify that the device node looks sane */
- if (fstat(fd, &st) == -1 || !S_ISCHR(st.st_mode)) {
- close(fd);
- goto nodevrandom;
- }
- if (ioctl(fd, RNDGETENTCNT, &cnt) == -1) {
- close(fd);
- goto nodevrandom;
- }
- for (i = 0; i < len; ) {
- size_t wanted = len - i;
- ssize_t ret = read(fd, (char*)buf + i, wanted);
-
- if (ret == -1) {
- if (errno == EAGAIN || errno == EINTR)
- continue;
- close(fd);
- goto nodevrandom;
- }
- i += ret;
- }
- close(fd);
- if (gotdata(buf, len) == 0) {
- errno = save_errno;
- return 0; /* satisfied */
- }
-nodevrandom:
- errno = EIO;
- return -1;
-}
-
-#ifdef SYS__sysctl
-static int
-getentropy_sysctl(void *buf, size_t len)
-{
- static int mib[] = { CTL_KERN, KERN_RANDOM, RANDOM_UUID };
- size_t i;
- int save_errno = errno;
-
- for (i = 0; i < len; ) {
- size_t chunk = min(len - i, 16);
-
- /* SYS__sysctl because some systems already removed sysctl() */
- struct __sysctl_args args = {
- .name = mib,
- .nlen = 3,
- .oldval = (char *)buf + i,
- .oldlenp = &chunk,
- };
- if (syscall(SYS__sysctl, &args) != 0)
- goto sysctlfailed;
- i += chunk;
- }
- if (gotdata(buf, len) == 0) {
- errno = save_errno;
- return (0); /* satisfied */
- }
-sysctlfailed:
- errno = EIO;
- return -1;
-}
-#endif /* SYS__sysctl */
-
-static int cl[] = {
- CLOCK_REALTIME,
-#ifdef CLOCK_MONOTONIC
- CLOCK_MONOTONIC,
-#endif
-#ifdef CLOCK_MONOTONIC_RAW
- CLOCK_MONOTONIC_RAW,
-#endif
-#ifdef CLOCK_TAI
- CLOCK_TAI,
-#endif
-#ifdef CLOCK_VIRTUAL
- CLOCK_VIRTUAL,
-#endif
-#ifdef CLOCK_UPTIME
- CLOCK_UPTIME,
-#endif
-#ifdef CLOCK_PROCESS_CPUTIME_ID
- CLOCK_PROCESS_CPUTIME_ID,
-#endif
-#ifdef CLOCK_THREAD_CPUTIME_ID
- CLOCK_THREAD_CPUTIME_ID,
-#endif
-};
-
-static int
-getentropy_fallback(void *buf, size_t len)
-{
- uint8_t results[SHA512_DIGEST_LENGTH];
- int save_errno = errno, e, pgs = getpagesize(), faster = 0, repeat;
- static int cnt;
- struct timespec ts;
- struct timeval tv;
- struct rusage ru;
- sigset_t sigset;
- struct stat st;
- CRYPTO_SHA512_CTX ctx;
- static pid_t lastpid;
- pid_t pid;
- size_t i, ii, m;
- char *p;
-
- pid = getpid();
- if (lastpid == pid) {
- faster = 1;
- repeat = 2;
- } else {
- faster = 0;
- lastpid = pid;
- repeat = REPEAT;
- }
- for (i = 0; i < len; ) {
- int j;
- CRYPTO_SHA512_INIT(&ctx);
- for (j = 0; j < repeat; j++) {
- HX((e = gettimeofday(&tv, NULL)) == -1, tv);
- if (e != -1) {
- cnt += (int)tv.tv_sec;
- cnt += (int)tv.tv_usec;
- }
-
- for (ii = 0; ii < sizeof(cl)/sizeof(cl[0]); ii++)
- HX(clock_gettime(cl[ii], &ts) == -1, ts);
-
- HX((pid = getpid()) == -1, pid);
- HX((pid = getsid(pid)) == -1, pid);
- HX((pid = getppid()) == -1, pid);
- HX((pid = getpgid(0)) == -1, pid);
- HX((e = getpriority(0, 0)) == -1, e);
-
- if (!faster) {
- ts.tv_sec = 0;
- ts.tv_nsec = 1;
- (void) nanosleep(&ts, NULL);
- }
-
- HX(sigpending(&sigset) == -1, sigset);
- HX(sigprocmask(SIG_BLOCK, NULL, &sigset) == -1,
- sigset);
-
-#ifdef CAN_REFERENCE_MAIN
- HF(main); /* an addr in program */
-#endif
- HF(getentropy); /* an addr in this library */
- HF(printf); /* an addr in libc */
- p = (char *)&p;
- HD(p); /* an addr on stack */
- p = (char *)&errno;
- HD(p); /* the addr of errno */
-
- if (i == 0) {
- struct sockaddr_storage ss;
- struct statvfs stvfs;
- struct termios tios;
- struct statfs stfs;
- socklen_t ssl;
- off_t off;
-
- /*
- * Prime-sized mappings encourage fragmentation;
- * thus exposing some address entropy.
- */
- struct mm {
- size_t npg;
- void *p;
- } mm[] = {
- { 17, MAP_FAILED }, { 3, MAP_FAILED },
- { 11, MAP_FAILED }, { 2, MAP_FAILED },
- { 5, MAP_FAILED }, { 3, MAP_FAILED },
- { 7, MAP_FAILED }, { 1, MAP_FAILED },
- { 57, MAP_FAILED }, { 3, MAP_FAILED },
- { 131, MAP_FAILED }, { 1, MAP_FAILED },
- };
-
- for (m = 0; m < sizeof mm/sizeof(mm[0]); m++) {
- HX(mm[m].p = mmap(NULL,
- mm[m].npg * pgs,
- PROT_READ|PROT_WRITE,
- MAP_PRIVATE|MAP_ANON, -1,
- (off_t)0), mm[m].p);
- if (mm[m].p != MAP_FAILED) {
- size_t mo;
-
- /* Touch some memory... */
- p = mm[m].p;
- mo = cnt %
- (mm[m].npg * pgs - 1);
- p[mo] = 1;
- cnt += (int)((long)(mm[m].p)
- / pgs);
- }
-
- /* Check cnts and times... */
- for (ii = 0; ii < sizeof(cl)/sizeof(cl[0]);
- ii++) {
- HX((e = clock_gettime(cl[ii],
- &ts)) == -1, ts);
- if (e != -1)
- cnt += (int)ts.tv_nsec;
- }
-
- HX((e = getrusage(RUSAGE_SELF,
- &ru)) == -1, ru);
- if (e != -1) {
- cnt += (int)ru.ru_utime.tv_sec;
- cnt += (int)ru.ru_utime.tv_usec;
- }
- }
-
- for (m = 0; m < sizeof mm/sizeof(mm[0]); m++) {
- if (mm[m].p != MAP_FAILED)
- munmap(mm[m].p, mm[m].npg * pgs);
- mm[m].p = MAP_FAILED;
- }
-
- HX(stat(".", &st) == -1, st);
- HX(statvfs(".", &stvfs) == -1, stvfs);
- HX(statfs(".", &stfs) == -1, stfs);
-
- HX(stat("/", &st) == -1, st);
- HX(statvfs("/", &stvfs) == -1, stvfs);
- HX(statfs("/", &stfs) == -1, stfs);
-
- HX((e = fstat(0, &st)) == -1, st);
- if (e == -1) {
- if (S_ISREG(st.st_mode) ||
- S_ISFIFO(st.st_mode) ||
- S_ISSOCK(st.st_mode)) {
- HX(fstatvfs(0, &stvfs) == -1,
- stvfs);
- HX(fstatfs(0, &stfs) == -1,
- stfs);
- HX((off = lseek(0, (off_t)0,
- SEEK_CUR)) < 0, off);
- }
- if (S_ISCHR(st.st_mode)) {
- HX(tcgetattr(0, &tios) == -1,
- tios);
- } else if (S_ISSOCK(st.st_mode)) {
- memset(&ss, 0, sizeof ss);
- ssl = sizeof(ss);
- HX(getpeername(0,
- (void *)&ss, &ssl) == -1,
- ss);
- }
- }
-
- HX((e = getrusage(RUSAGE_CHILDREN,
- &ru)) == -1, ru);
- if (e != -1) {
- cnt += (int)ru.ru_utime.tv_sec;
- cnt += (int)ru.ru_utime.tv_usec;
- }
- } else {
- /* Subsequent hashes absorb previous result */
- HD(results);
- }
-
- HX((e = gettimeofday(&tv, NULL)) == -1, tv);
- if (e != -1) {
- cnt += (int)tv.tv_sec;
- cnt += (int)tv.tv_usec;
- }
-
- HD(cnt);
- }
-#ifdef HAVE_GETAUXVAL
-# ifdef AT_RANDOM
- /* Not as random as you think but we take what we are given */
- p = (char *) getauxval(AT_RANDOM);
- if (p)
- HR(p, 16);
-# endif
-# ifdef AT_SYSINFO_EHDR
- p = (char *) getauxval(AT_SYSINFO_EHDR);
- if (p)
- HR(p, pgs);
-# endif
-# ifdef AT_BASE
- p = (char *) getauxval(AT_BASE);
- if (p)
- HD(p);
-# endif
-#endif /* HAVE_GETAUXVAL */
-
- CRYPTO_SHA512_FINAL(results, &ctx);
- memcpy((char*)buf + i, results, min(sizeof(results), len - i));
- i += min(sizeof(results), len - i);
- }
- memset(results, 0, sizeof results);
- if (gotdata(buf, len) == 0) {
- errno = save_errno;
- return 0; /* satisfied */
- }
- errno = EIO;
- return -1;
-}
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