add initial HP-UX getentropy/arc4random support.
authorbcook <bcook@openbsd.org>
Tue, 6 Jan 2015 21:08:11 +0000 (21:08 +0000)
committerbcook <bcook@openbsd.org>
Tue, 6 Jan 2015 21:08:11 +0000 (21:08 +0000)
patch from Kinichiro Inoguchi, tested on HP-UX 11.31

ok deraadt@

lib/libcrypto/arc4random/arc4random_hpux.h [new file with mode: 0644]
lib/libcrypto/arc4random/getentropy_hpux.c [new file with mode: 0644]
lib/libcrypto/crypto/arc4random_hpux.h [new file with mode: 0644]
lib/libcrypto/crypto/getentropy_hpux.c [new file with mode: 0644]

diff --git a/lib/libcrypto/arc4random/arc4random_hpux.h b/lib/libcrypto/arc4random/arc4random_hpux.h
new file mode 100644 (file)
index 0000000..b6841f5
--- /dev/null
@@ -0,0 +1,79 @@
+/*     $OpenBSD: arc4random_hpux.h,v 1.1 2015/01/06 21:08:11 bcook Exp $       */
+
+/*
+ * Copyright (c) 1996, David Mazieres <dm@uun.org>
+ * Copyright (c) 2008, Damien Miller <djm@openbsd.org>
+ * Copyright (c) 2013, Markus Friedl <markus@openbsd.org>
+ *
+ * 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.
+ */
+
+/*
+ * Stub functions for portability.
+ */
+
+#include <sys/mman.h>
+
+#include <pthread.h>
+#include <signal.h>
+
+static pthread_mutex_t arc4random_mtx = PTHREAD_MUTEX_INITIALIZER;
+#define _ARC4_LOCK()   pthread_mutex_lock(&arc4random_mtx)
+#define _ARC4_UNLOCK() pthread_mutex_unlock(&arc4random_mtx)
+
+#define _ARC4_ATFORK(f) pthread_atfork(NULL, NULL, (f))
+
+static inline void
+_getentropy_fail(void)
+{
+       raise(SIGKILL);
+}
+
+static volatile sig_atomic_t _rs_forked;
+
+static inline void
+_rs_forkhandler(void)
+{
+       _rs_forked = 1;
+}
+
+static inline void
+_rs_forkdetect(void)
+{
+       static pid_t _rs_pid = 0;
+       pid_t pid = getpid();
+
+       if (_rs_pid == 0 || _rs_pid != pid || _rs_forked) {
+               _rs_pid = pid;
+               _rs_forked = 0;
+               if (rs)
+                       memset(rs, 0, sizeof(*rs));
+       }
+}
+
+static inline int
+_rs_allocate(struct _rs **rsp, struct _rsx **rsxp)
+{
+       if ((*rsp = mmap(NULL, sizeof(**rsp), PROT_READ|PROT_WRITE,
+           MAP_ANON|MAP_PRIVATE, -1, 0)) == MAP_FAILED)
+               return (-1);
+
+       if ((*rsxp = mmap(NULL, sizeof(**rsxp), PROT_READ|PROT_WRITE,
+           MAP_ANON|MAP_PRIVATE, -1, 0)) == MAP_FAILED) {
+               munmap(*rsp, sizeof(**rsp));
+               return (-1);
+       }
+
+       _ARC4_ATFORK(_rs_forkhandler);
+       return (0);
+}
diff --git a/lib/libcrypto/arc4random/getentropy_hpux.c b/lib/libcrypto/arc4random/getentropy_hpux.c
new file mode 100644 (file)
index 0000000..46ab8f5
--- /dev/null
@@ -0,0 +1,417 @@
+/*     $OpenBSD: getentropy_hpux.c,v 1.1 2015/01/06 21:08:11 bcook 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.
+ *
+ * Emulation of getentropy(2) as documented at:
+ * http://www.openbsd.org/cgi-bin/man.cgi/OpenBSD-current/man2/getentropy.2
+ */
+
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/ioctl.h>
+#include <sys/resource.h>
+#include <sys/syscall.h>
+#include <sys/statvfs.h>
+#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>
+#include <openssl/sha.h>
+
+#include <sys/vfs.h>
+
+#include <sys/pstat.h>
+
+#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_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_getprocvm(&pvs, sizeof(pvs), 0, 0) != 1, pvs.pst_space);
+
+                       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/lib/libcrypto/crypto/arc4random_hpux.h b/lib/libcrypto/crypto/arc4random_hpux.h
new file mode 100644 (file)
index 0000000..b6841f5
--- /dev/null
@@ -0,0 +1,79 @@
+/*     $OpenBSD: arc4random_hpux.h,v 1.1 2015/01/06 21:08:11 bcook Exp $       */
+
+/*
+ * Copyright (c) 1996, David Mazieres <dm@uun.org>
+ * Copyright (c) 2008, Damien Miller <djm@openbsd.org>
+ * Copyright (c) 2013, Markus Friedl <markus@openbsd.org>
+ *
+ * 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.
+ */
+
+/*
+ * Stub functions for portability.
+ */
+
+#include <sys/mman.h>
+
+#include <pthread.h>
+#include <signal.h>
+
+static pthread_mutex_t arc4random_mtx = PTHREAD_MUTEX_INITIALIZER;
+#define _ARC4_LOCK()   pthread_mutex_lock(&arc4random_mtx)
+#define _ARC4_UNLOCK() pthread_mutex_unlock(&arc4random_mtx)
+
+#define _ARC4_ATFORK(f) pthread_atfork(NULL, NULL, (f))
+
+static inline void
+_getentropy_fail(void)
+{
+       raise(SIGKILL);
+}
+
+static volatile sig_atomic_t _rs_forked;
+
+static inline void
+_rs_forkhandler(void)
+{
+       _rs_forked = 1;
+}
+
+static inline void
+_rs_forkdetect(void)
+{
+       static pid_t _rs_pid = 0;
+       pid_t pid = getpid();
+
+       if (_rs_pid == 0 || _rs_pid != pid || _rs_forked) {
+               _rs_pid = pid;
+               _rs_forked = 0;
+               if (rs)
+                       memset(rs, 0, sizeof(*rs));
+       }
+}
+
+static inline int
+_rs_allocate(struct _rs **rsp, struct _rsx **rsxp)
+{
+       if ((*rsp = mmap(NULL, sizeof(**rsp), PROT_READ|PROT_WRITE,
+           MAP_ANON|MAP_PRIVATE, -1, 0)) == MAP_FAILED)
+               return (-1);
+
+       if ((*rsxp = mmap(NULL, sizeof(**rsxp), PROT_READ|PROT_WRITE,
+           MAP_ANON|MAP_PRIVATE, -1, 0)) == MAP_FAILED) {
+               munmap(*rsp, sizeof(**rsp));
+               return (-1);
+       }
+
+       _ARC4_ATFORK(_rs_forkhandler);
+       return (0);
+}
diff --git a/lib/libcrypto/crypto/getentropy_hpux.c b/lib/libcrypto/crypto/getentropy_hpux.c
new file mode 100644 (file)
index 0000000..46ab8f5
--- /dev/null
@@ -0,0 +1,417 @@
+/*     $OpenBSD: getentropy_hpux.c,v 1.1 2015/01/06 21:08:11 bcook 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.
+ *
+ * Emulation of getentropy(2) as documented at:
+ * http://www.openbsd.org/cgi-bin/man.cgi/OpenBSD-current/man2/getentropy.2
+ */
+
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/ioctl.h>
+#include <sys/resource.h>
+#include <sys/syscall.h>
+#include <sys/statvfs.h>
+#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>
+#include <openssl/sha.h>
+
+#include <sys/vfs.h>
+
+#include <sys/pstat.h>
+
+#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_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_getprocvm(&pvs, sizeof(pvs), 0, 0) != 1, pvs.pst_space);
+
+                       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;
+}