From 9a9a8b2dba2f511c0888499726597add59ae1215 Mon Sep 17 00:00:00 2001 From: Guillem Jover Date: Wed, 23 Sep 2015 19:39:47 +0200 Subject: [PATCH] Add private getentropy module from OpenBSD and LibreSSL Adapt the code to the local build system. --- configure.ac | 4 +- src/Makefile.am | 12 + src/getentropy.c | 43 +++ src/getentropy_aix.c | 425 ++++++++++++++++++++++++++++++ src/getentropy_bsd.c | 62 +++++ src/getentropy_hpux.c | 419 ++++++++++++++++++++++++++++++ src/getentropy_linux.c | 547 +++++++++++++++++++++++++++++++++++++++ src/getentropy_osx.c | 429 ++++++++++++++++++++++++++++++ src/getentropy_solaris.c | 445 +++++++++++++++++++++++++++++++ 9 files changed, 2385 insertions(+), 1 deletion(-) create mode 100644 src/getentropy.c create mode 100644 src/getentropy_aix.c create mode 100644 src/getentropy_bsd.c create mode 100644 src/getentropy_hpux.c create mode 100644 src/getentropy_linux.c create mode 100644 src/getentropy_osx.c create mode 100644 src/getentropy_solaris.c diff --git a/configure.ac b/configure.ac index 3b75267..0e797ce 100644 --- a/configure.ac +++ b/configure.ac @@ -128,8 +128,10 @@ AC_LINK_IFELSE( AC_MSG_RESULT([yes])], [AC_MSG_RESULT([no])]) -AC_CHECK_FUNCS([clearenv dirfd fopencookie __fpurge getexecname getline \ +AC_CHECK_FUNCS([clearenv dirfd fopencookie __fpurge \ + getentropy getexecname getline \ pstat_getproc sysconf]) +AM_CONDITIONAL(HAVE_GETENTROPY, [test "x$ac_cv_func_getentropy" = "xtrue"]) AC_CONFIG_FILES([ Makefile diff --git a/src/Makefile.am b/src/Makefile.am index c8db76e..bd490fd 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -9,6 +9,12 @@ AM_CPPFLAGS = \ libbsd_la_included_sources = \ hash/helper.c \ + getentropy_aix.c \ + getentropy_bsd.c \ + getentropy_hpux.c \ + getentropy_linux.c \ + getentropy_osx.c \ + getentropy_solaris.c \ $(nil) EXTRA_DIST = \ @@ -97,6 +103,12 @@ libbsd_la_SOURCES = \ wcslcpy.c \ $(nil) +if !HAVE_GETENTROPY +libbsd_la_SOURCES += \ + getentropy.c \ + $(nil) +endif + libbsd_ctor_a_SOURCES = \ setproctitle_ctor.c \ $(nil) diff --git a/src/getentropy.c b/src/getentropy.c new file mode 100644 index 0000000..f22b850 --- /dev/null +++ b/src/getentropy.c @@ -0,0 +1,43 @@ +/* + * Copyright © 2015 Guillem Jover + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, + * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY + * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL + * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, + * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, + * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; + * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, + * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR + * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF + * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#if defined(__linux__) +#include "getentropy_linux.c" +#elif defined(__FreeBSD__) +#include "arc4random_bsd.c" +#elif defined(__NetBSD__) +#include "arc4random_bsd.c" +#elif defined(__sun) +#include "arc4random_solaris.c" +#elif defined(__APPLE__) +#include "arc4random_osx.c" +#elif defined(_AIX) +#include "arc4random_aix.c" +#elif defined(__hpux) +#include "arc4random_hpux.c" +#else +#error "No getentropy hooks defined for this platform." +#endif diff --git a/src/getentropy_aix.c b/src/getentropy_aix.c new file mode 100644 index 0000000..cbd4037 --- /dev/null +++ b/src/getentropy_aix.c @@ -0,0 +1,425 @@ +/* $OpenBSD: getentropy_aix.c,v 1.3 2015/08/25 17:26:43 deraadt Exp $ */ + +/* + * Copyright (c) 2015 Michael Felt + * Copyright (c) 2014 Theo de Raadt + * Copyright (c) 2014 Bob Beck + * + * 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. + * + * Emulation of getentropy(2) as documented at: + * http://www.openbsd.org/cgi-bin/man.cgi/OpenBSD-current/man2/getentropy.2 + */ +/* + * -lperfstat is needed for the psuedo entropy data + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +#include + +#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) + +#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*))) + +int getentropy(void *buf, size_t len); + +static int gotdata(char *buf, size_t len); +static int getentropy_urandom(void *buf, size_t len, const char *path, + int devfscheck); +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); + } + + /* + * Try to get entropy with /dev/urandom + */ + ret = getentropy_urandom(buf, len, "/dev/urandom", 0); + if (ret != -1) + return (ret); + + /* + * Entropy collection via /dev/urandom has failed. + * + * No other API exists for collecting entropy, and we have + * no failsafe way to get it on AIX that is not sensitive + * to resource exhaustion. + * + * 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 AIX + * does not provide a failsafe API for entropy collection. + * + * We hope this demonstrates that AIX should 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); +} + +static int +getentropy_urandom(void *buf, size_t len, const char *path, int devfscheck) +{ + struct stat st; + size_t i; + int fd, 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(path, 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; + } + 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); +} + +static const 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 = sysconf(_SC_PAGESIZE), faster = 0, repeat; + static int cnt; + struct timespec ts; + struct timeval tv; + perfstat_cpu_total_t cpustats; +#ifdef _AIX61 + perfstat_cpu_total_wpar_t cpustats_wpar; +#endif + perfstat_partition_total_t lparstats; + perfstat_disk_total_t diskinfo; + perfstat_netinterface_total_t netinfo; + struct rusage ru; + sigset_t sigset; + struct stat st; + 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; + 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; + } + + HX(perfstat_cpu_total(NULL, &cpustats, + sizeof(cpustats), 1) == -1, cpustats); + +#ifdef _AIX61 + HX(perfstat_cpu_total_wpar(NULL, &cpustats_wpar, + sizeof(cpustats_wpar), 1) == -1, cpustats_wpar); +#endif + + HX(perfstat_partition_total(NULL, &lparstats, + sizeof(lparstats), 1) == -1, lparstats); + + HX(perfstat_disk_total(NULL, &diskinfo, + sizeof(diskinfo), 1) == -1, diskinfo); + + HX(perfstat_netinterface_total(NULL, &netinfo, + sizeof(netinfo), 1) == -1, netinfo); + + 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); + + 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; + 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(stat("/", &st) == -1, st); + HX(statvfs("/", &stvfs) == -1, stvfs); + + 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((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); + } + SHA512_Final(results, &ctx); + memcpy((char *)buf + i, results, min(sizeof(results), len - i)); + i += min(sizeof(results), len - i); + } + explicit_bzero(&ctx, sizeof ctx); + explicit_bzero(results, sizeof results); + if (gotdata(buf, len) == 0) { + errno = save_errno; + return (0); /* satisfied */ + } + errno = EIO; + return (-1); +} diff --git a/src/getentropy_bsd.c b/src/getentropy_bsd.c new file mode 100644 index 0000000..1959984 --- /dev/null +++ b/src/getentropy_bsd.c @@ -0,0 +1,62 @@ +/* $OpenBSD: getentropy_freebsd.c,v 1.1 2014/11/03 06:23:30 bcook Exp $ */ + +/* + * Copyright (c) 2014 Pawel Jakub Dawidek + * Copyright (c) 2014 Brent Cook + * + * 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. + * + * Emulation of getentropy(2) as documented at: + * http://www.openbsd.org/cgi-bin/man.cgi/OpenBSD-current/man2/getentropy.2 + */ + +#include +#include + +#include +#include + +/* + * Derived from lib/libc/gen/arc4random.c from FreeBSD. + */ +static size_t +getentropy_sysctl(u_char *buf, size_t size) +{ + int mib[2]; + size_t len, done; + + mib[0] = CTL_KERN; + mib[1] = KERN_ARND; + done = 0; + + do { + len = size; + if (sysctl(mib, 2, buf, &len, NULL, 0) == -1) + return (done); + done += len; + buf += len; + size -= len; + } while (size > 0); + + return (done); +} + +int +getentropy(void *buf, size_t len) +{ + if (len <= 256 && getentropy_sysctl(buf, len) == len) + return (0); + + errno = EIO; + return (-1); +} diff --git a/src/getentropy_hpux.c b/src/getentropy_hpux.c new file mode 100644 index 0000000..45ac84b --- /dev/null +++ b/src/getentropy_hpux.c @@ -0,0 +1,419 @@ +/* $OpenBSD: getentropy_hpux.c,v 1.3 2015/08/25 17:26:43 deraadt Exp $ */ + +/* + * Copyright (c) 2014 Theo de Raadt + * Copyright (c) 2014 Bob Beck + * + * 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. + * + * Emulation of getentropy(2) as documented at: + * http://www.openbsd.org/cgi-bin/man.cgi/OpenBSD-current/man2/getentropy.2 + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +#include + +#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) + +#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*))) + +int getentropy(void *buf, size_t len); + +static int gotdata(char *buf, size_t len); +static int getentropy_urandom(void *buf, size_t len, const char *path, + int devfscheck); +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); + } + + /* + * Try to get entropy with /dev/urandom + */ + ret = getentropy_urandom(buf, len, "/dev/urandom", 0); + if (ret != -1) + return (ret); + + /* + * Entropy collection via /dev/urandom has failed. + * + * No other API exists for collecting entropy, and we have + * no failsafe way to get it on hpux that is not sensitive + * to resource exhaustion. + * + * 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 hpux + * does not provide a failsafe API for entropy collection. + * + * We hope this demonstrates that hpux should 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); +} + +static int +getentropy_urandom(void *buf, size_t len, const char *path, int devfscheck) +{ + struct stat st; + size_t i; + int fd, 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(path, 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; + } + 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); +} + +static const 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 = sysconf(_SC_PAGESIZE), faster = 0, repeat; + static int cnt; + struct timespec ts; + struct timeval tv; + struct pst_vminfo pvi; + struct pst_vm_status pvs; + struct pst_dynamic pdy; + struct rusage ru; + sigset_t sigset; + struct stat st; + 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; + 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; + } + + HX(pstat_getvminfo(&pvi, sizeof(pvi), 1, 0) != 1, pvi); + HX(pstat_getprocvm(&pvs, sizeof(pvs), 0, 0) != 1, pvs); + + 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(pstat_getdynamic(&pdy, sizeof(pdy), 1, 0) != 1) { + HD(errno); + } else { + HD(pdy.psd_avg_1_min); + HD(pdy.psd_avg_5_min); + HD(pdy.psd_avg_15_min); + } + + 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); + + 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; + 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(stat("/", &st) == -1, st); + HX(statvfs("/", &stvfs) == -1, stvfs); + + 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((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); + } + SHA512_Final(results, &ctx); + memcpy((char *)buf + i, results, min(sizeof(results), len - i)); + i += min(sizeof(results), len - i); + } + explicit_bzero(&ctx, sizeof ctx); + explicit_bzero(results, sizeof results); + if (gotdata(buf, len) == 0) { + errno = save_errno; + return (0); /* satisfied */ + } + errno = EIO; + return (-1); +} diff --git a/src/getentropy_linux.c b/src/getentropy_linux.c new file mode 100644 index 0000000..0a5d6b8 --- /dev/null +++ b/src/getentropy_linux.c @@ -0,0 +1,547 @@ +/* $OpenBSD: getentropy_linux.c,v 1.40 2015/08/25 17:26:43 deraadt Exp $ */ + +/* + * Copyright (c) 2014 Theo de Raadt + * Copyright (c) 2014 Bob Beck + * + * 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. + * + * Emulation of getentropy(2) as documented at: + * http://www.openbsd.org/cgi-bin/man.cgi/OpenBSD-current/man2/getentropy.2 + */ + +#define _POSIX_C_SOURCE 199309L +#define _GNU_SOURCE 1 +#include +#include +#include +#include +#include +#ifdef SYS__sysctl +#include +#endif +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#ifdef HAVE_GETAUXVAL +#include +#endif +#include + +#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) + +#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*))) + +int getentropy(void *buf, size_t len); + +static int gotdata(char *buf, size_t len); +#ifdef SYS_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); +static int getentropy_phdr(struct dl_phdr_info *info, size_t size, void *data); + +int +getentropy(void *buf, size_t len) +{ + int ret = -1; + + if (len > 256) { + errno = EIO; + return (-1); + } + +#ifdef SYS_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 + * exhuasted. + * + * 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); +} + +#ifdef SYS_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 const 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_phdr(struct dl_phdr_info *info, size_t size, void *data) +{ + SHA512_CTX *ctx = data; + + SHA512_Update(ctx, &info->dlpi_addr, sizeof (info->dlpi_addr)); + return (0); +} + +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; + 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; + 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; + } + + dl_iterate_phdr(getentropy_phdr, &ctx); + + 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); + + 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 + + SHA512_Final(results, &ctx); + memcpy((char *)buf + i, results, min(sizeof(results), len - i)); + i += min(sizeof(results), len - i); + } + explicit_bzero(&ctx, sizeof ctx); + explicit_bzero(results, sizeof results); + if (gotdata(buf, len) == 0) { + errno = save_errno; + return (0); /* satisfied */ + } + errno = EIO; + return (-1); +} diff --git a/src/getentropy_osx.c b/src/getentropy_osx.c new file mode 100644 index 0000000..db67c4b --- /dev/null +++ b/src/getentropy_osx.c @@ -0,0 +1,429 @@ +/* $OpenBSD: getentropy_osx.c,v 1.8 2014/07/21 20:19:47 guenther Exp $ */ + +/* + * Copyright (c) 2014 Theo de Raadt + * Copyright (c) 2014 Bob Beck + * + * 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. + * + * Emulation of getentropy(2) as documented at: + * http://www.openbsd.org/cgi-bin/man.cgi/OpenBSD-current/man2/getentropy.2 + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#define SHA512_Update(a, b, c) (CC_SHA512_Update((a), (b), (c))) +#define SHA512_Init(xxx) (CC_SHA512_Init((xxx))) +#define SHA512_Final(xxx, yyy) (CC_SHA512_Final((xxx), (yyy))) +#define SHA512_CTX CC_SHA512_CTX +#define SHA512_DIGEST_LENGTH CC_SHA512_DIGEST_LENGTH + +#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) + +#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*))) + +int getentropy(void *buf, size_t len); + +static int gotdata(char *buf, size_t len); +static int getentropy_urandom(void *buf, size_t len); +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); + } + + /* + * 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); + + /* + * Entropy collection via /dev/urandom and sysctl have failed. + * + * No other API exists for collecting entropy, and we have + * no failsafe way to get it on OSX that is not sensitive + * to resource exhaustion. + * + * 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 OSX + * does not provide a failsafe API for entropy collection. + * + * We hope this demonstrates that OSX should 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); +} + +static int +getentropy_urandom(void *buf, size_t len) +{ + struct stat st; + size_t i; + int fd, 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; + } + 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); +} + +static int tcpmib[] = { CTL_NET, AF_INET, IPPROTO_TCP, TCPCTL_STATS }; +static int udpmib[] = { CTL_NET, AF_INET, IPPROTO_UDP, UDPCTL_STATS }; +static int ipmib[] = { CTL_NET, AF_INET, IPPROTO_IP, IPCTL_STATS }; +static int kmib[] = { CTL_KERN, KERN_USRSTACK }; +static int hwmib[] = { CTL_HW, HW_USERMEM }; + +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; + SHA512_CTX ctx; + static pid_t lastpid; + pid_t pid; + size_t i, ii, m; + char *p; + struct tcpstat tcpstat; + struct udpstat udpstat; + struct ipstat ipstat; + uint64_t mach_time; + unsigned int idata; + void *addr; + + pid = getpid(); + if (lastpid == pid) { + faster = 1; + repeat = 2; + } else { + faster = 0; + lastpid = pid; + repeat = REPEAT; + } + for (i = 0; i < len; ) { + int j; + 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; + } + + mach_time = mach_absolute_time(); + HD(mach_time); + + ii = sizeof(addr); + HX(sysctl(kmib, sizeof(kmib) / sizeof(kmib[0]), + &addr, &ii, NULL, 0) == -1, addr); + + ii = sizeof(idata); + HX(sysctl(hwmib, sizeof(hwmib) / sizeof(hwmib[0]), + &idata, &ii, NULL, 0) == -1, idata); + + ii = sizeof(tcpstat); + HX(sysctl(tcpmib, sizeof(tcpmib) / sizeof(tcpmib[0]), + &tcpstat, &ii, NULL, 0) == -1, tcpstat); + + ii = sizeof(udpstat); + HX(sysctl(udpmib, sizeof(udpmib) / sizeof(udpmib[0]), + &udpstat, &ii, NULL, 0) == -1, udpstat); + + ii = sizeof(ipstat); + HX(sysctl(ipmib, sizeof(ipmib) / sizeof(ipmib[0]), + &ipstat, &ii, NULL, 0) == -1, ipstat); + + 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); + + 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... */ + mach_time = mach_absolute_time(); + HD(mach_time); + cnt += (int)mach_time; + + 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); + } + + SHA512_Final(results, &ctx); + memcpy((char *)buf + i, results, min(sizeof(results), len - i)); + i += min(sizeof(results), len - i); + } + explicit_bzero(&ctx, sizeof ctx); + explicit_bzero(results, sizeof results); + if (gotdata(buf, len) == 0) { + errno = save_errno; + return (0); /* satisfied */ + } + errno = EIO; + return (-1); +} diff --git a/src/getentropy_solaris.c b/src/getentropy_solaris.c new file mode 100644 index 0000000..ca787f8 --- /dev/null +++ b/src/getentropy_solaris.c @@ -0,0 +1,445 @@ +/* $OpenBSD: getentropy_solaris.c,v 1.10 2015/08/25 17:26:43 deraadt Exp $ */ + +/* + * Copyright (c) 2014 Theo de Raadt + * Copyright (c) 2014 Bob Beck + * + * 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. + * + * Emulation of getentropy(2) as documented at: + * http://www.openbsd.org/cgi-bin/man.cgi/OpenBSD-current/man2/getentropy.2 + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#define SHA512_Init SHA512Init +#define SHA512_Update SHA512Update +#define SHA512_Final SHA512Final + +#include +#include +#include + +#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) + +#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*))) + +int getentropy(void *buf, size_t len); + +static int gotdata(char *buf, size_t len); +static int getentropy_urandom(void *buf, size_t len, const char *path, + int devfscheck); +static int getentropy_fallback(void *buf, size_t len); +static int getentropy_phdr(struct dl_phdr_info *info, size_t size, void *data); + +int +getentropy(void *buf, size_t len) +{ + int ret = -1; + + if (len > 256) { + errno = EIO; + return (-1); + } + + /* + * Try to get entropy with /dev/urandom + * + * Solaris provides /dev/urandom as a symbolic link to + * /devices/pseudo/random@0:urandom which is provided by + * a devfs filesystem. Best practice is to use O_NOFOLLOW, + * so we must try the unpublished name directly. + * + * This can fail if the process is inside a chroot which lacks + * the devfs mount, or if file descriptors are exhausted. + */ + ret = getentropy_urandom(buf, len, + "/devices/pseudo/random@0:urandom", 1); + if (ret != -1) + return (ret); + + /* + * Unfortunately, chroot spaces on Solaris are sometimes setup + * with direct device node of the well-known /dev/urandom name + * (perhaps to avoid dragging all of devfs into the space). + * + * This can fail if the process is inside a chroot or if file + * descriptors are exhausted. + */ + ret = getentropy_urandom(buf, len, "/dev/urandom", 0); + if (ret != -1) + return (ret); + + /* + * Entropy collection via /dev/urandom has failed. + * + * No other API exists for collecting entropy, and we have + * no failsafe way to get it on Solaris that is not sensitive + * to resource exhaustion. + * + * 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 Solaris + * does not provide a failsafe API for entropy collection. + * + * We hope this demonstrates that Solaris should 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); +} + +static int +getentropy_urandom(void *buf, size_t len, const char *path, int devfscheck) +{ + struct stat st; + size_t i; + int fd, 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(path, 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) || + (devfscheck && (strcmp(st.st_fstype, "devfs") != 0))) { + 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); +} + +static const 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_phdr(struct dl_phdr_info *info, size_t size, void *data) +{ + SHA512_CTX *ctx = data; + + SHA512_Update(ctx, &info->dlpi_addr, sizeof (info->dlpi_addr)); + return (0); +} + +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; + double loadavg[3]; + struct rusage ru; + sigset_t sigset; + struct stat st; + 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; + 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; + } + + dl_iterate_phdr(getentropy_phdr, &ctx); + + 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); + HX((getloadavg(loadavg, 3) == -1), loadavg); + + 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); + + 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; + 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(stat("/", &st) == -1, st); + HX(statvfs("/", &stvfs) == -1, stvfs); + + 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((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); + } + SHA512_Final(results, &ctx); + memcpy((char *)buf + i, results, min(sizeof(results), len - i)); + i += min(sizeof(results), len - i); + } + explicit_bzero(&ctx, sizeof ctx); + explicit_bzero(results, sizeof results); + if (gotdata(buf, len) == 0) { + errno = save_errno; + return (0); /* satisfied */ + } + errno = EIO; + return (-1); +}