--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/nss/lib/freebl/unix_rand.c	Mon Jul 28 10:47:06 2014 +0200
@@ -0,0 +1,1192 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include <stdio.h>
+#include <string.h>
+#include <signal.h>
+#include <unistd.h>
+#include <limits.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <sys/time.h>
+#include <sys/wait.h>
+#include <sys/stat.h>
+#include "secrng.h"
+#include "secerr.h"
+#include "prerror.h"
+#include "prthread.h"
+#include "prprf.h"
+
+size_t RNG_FileUpdate(const char *fileName, size_t limit);
+
+/*
+ * When copying data to the buffer we want the least signicant bytes
+ * from the input since those bits are changing the fastest. The address
+ * of least significant byte depends upon whether we are running on
+ * a big-endian or little-endian machine.
+ *
+ * Does this mean the least signicant bytes are the most significant
+ * to us? :-)
+ */
+    
+static size_t CopyLowBits(void *dst, size_t dstlen, void *src, size_t srclen)
+{
+    union endianness {
+	PRInt32 i;
+	char c[4];
+    } u;
+
+    if (srclen <= dstlen) {
+	memcpy(dst, src, srclen);
+	return srclen;
+    }
+    u.i = 0x01020304;
+    if (u.c[0] == 0x01) {
+	/* big-endian case */
+	memcpy(dst, (char*)src + (srclen - dstlen), dstlen);
+    } else {
+	/* little-endian case */
+	memcpy(dst, src, dstlen);
+    }
+    return dstlen;
+}
+
+#ifdef SOLARIS
+
+#include <kstat.h>
+
+static const PRUint32 entropy_buf_len = 4096; /* buffer up to 4 KB */
+
+/* Buffer entropy data, and feed it to the RNG, entropy_buf_len bytes at a time.
+ * Returns error if RNG_RandomUpdate fails. Also increments *total_fed
+ * by the number of bytes successfully buffered.
+ */
+static SECStatus BufferEntropy(char* inbuf, PRUint32 inlen,
+                                char* entropy_buf, PRUint32* entropy_buffered,
+                                PRUint32* total_fed)
+{
+    PRUint32 tocopy = 0;
+    PRUint32 avail = 0;
+    SECStatus rv = SECSuccess;
+
+    while (inlen) {
+        avail = entropy_buf_len - *entropy_buffered;
+        if (!avail) {
+            /* Buffer is full, time to feed it to the RNG. */
+            rv = RNG_RandomUpdate(entropy_buf, entropy_buf_len);
+            if (SECSuccess != rv) {
+                break;
+            }
+            *entropy_buffered = 0;
+            avail = entropy_buf_len;
+        }
+        tocopy = PR_MIN(avail, inlen);
+        memcpy(entropy_buf + *entropy_buffered, inbuf, tocopy);
+        *entropy_buffered += tocopy;
+        inlen -= tocopy;
+        inbuf += tocopy;
+        *total_fed += tocopy;
+    }
+    return rv;
+}
+
+/* Feed kernel statistics structures and ks_data field to the RNG.
+ * Returns status as well as the number of bytes successfully fed to the RNG.
+ */
+static SECStatus RNG_kstat(PRUint32* fed)
+{
+    kstat_ctl_t*    kc = NULL;
+    kstat_t*        ksp = NULL;
+    PRUint32        entropy_buffered = 0;
+    char*           entropy_buf = NULL;
+    SECStatus       rv = SECSuccess;
+
+    PORT_Assert(fed);
+    if (!fed) {
+        return SECFailure;
+    }
+    *fed = 0;
+
+    kc = kstat_open();
+    PORT_Assert(kc);
+    if (!kc) {
+        return SECFailure;
+    }
+    entropy_buf = (char*) PORT_Alloc(entropy_buf_len);
+    PORT_Assert(entropy_buf);
+    if (entropy_buf) {
+        for (ksp = kc->kc_chain; ksp != NULL; ksp = ksp->ks_next) {
+            if (-1 == kstat_read(kc, ksp, NULL)) {
+                /* missing data from a single kstat shouldn't be fatal */
+                continue;
+            }
+            rv = BufferEntropy((char*)ksp, sizeof(kstat_t),
+                                    entropy_buf, &entropy_buffered,
+                                    fed);
+            if (SECSuccess != rv) {
+                break;
+            }
+
+            if (ksp->ks_data && ksp->ks_data_size>0 && ksp->ks_ndata>0) {
+                rv = BufferEntropy((char*)ksp->ks_data, ksp->ks_data_size,
+                                        entropy_buf, &entropy_buffered,
+                                        fed);
+                if (SECSuccess != rv) {
+                    break;
+                }
+            }
+        }
+        if (SECSuccess == rv && entropy_buffered) {
+            /* Buffer is not empty, time to feed it to the RNG */
+            rv = RNG_RandomUpdate(entropy_buf, entropy_buffered);
+        }
+        PORT_Free(entropy_buf);
+    } else {
+        rv = SECFailure;
+    }
+    if (kstat_close(kc)) {
+        PORT_Assert(0);
+        rv = SECFailure;
+    }
+    return rv;
+}
+
+#endif
+
+#if defined(SCO) || defined(UNIXWARE) || defined(BSDI) || defined(FREEBSD) \
+    || defined(NETBSD) || defined(DARWIN) || defined(OPENBSD) \
+    || defined(NTO) || defined(__riscos__)
+#include <sys/times.h>
+
+#define getdtablesize() sysconf(_SC_OPEN_MAX)
+
+static size_t
+GetHighResClock(void *buf, size_t maxbytes)
+{
+    int ticks;
+    struct tms buffer;
+
+    ticks=times(&buffer);
+    return CopyLowBits(buf, maxbytes, &ticks, sizeof(ticks));
+}
+
+static void
+GiveSystemInfo(void)
+{
+    long si;
+
+    /* 
+     * Is this really necessary?  Why not use rand48 or something?
+     */
+    si = sysconf(_SC_CHILD_MAX);
+    RNG_RandomUpdate(&si, sizeof(si));
+
+    si = sysconf(_SC_STREAM_MAX);
+    RNG_RandomUpdate(&si, sizeof(si));
+
+    si = sysconf(_SC_OPEN_MAX);
+    RNG_RandomUpdate(&si, sizeof(si));
+}
+#endif
+
+#if defined(__sun)
+#if defined(__svr4) || defined(SVR4)
+#include <sys/systeminfo.h>
+
+#define getdtablesize() sysconf(_SC_OPEN_MAX)
+
+static void
+GiveSystemInfo(void)
+{
+    int rv;
+    char buf[2000];
+
+    rv = sysinfo(SI_MACHINE, buf, sizeof(buf));
+    if (rv > 0) {
+	RNG_RandomUpdate(buf, rv);
+    }
+    rv = sysinfo(SI_RELEASE, buf, sizeof(buf));
+    if (rv > 0) {
+	RNG_RandomUpdate(buf, rv);
+    }
+    rv = sysinfo(SI_HW_SERIAL, buf, sizeof(buf));
+    if (rv > 0) {
+	RNG_RandomUpdate(buf, rv);
+    }
+}
+
+static size_t
+GetHighResClock(void *buf, size_t maxbytes)
+{
+    hrtime_t t;
+    t = gethrtime();
+    if (t) {
+	return CopyLowBits(buf, maxbytes, &t, sizeof(t));
+    }
+    return 0;
+}
+#else /* SunOS (Sun, but not SVR4) */
+
+extern long sysconf(int name);
+
+static size_t
+GetHighResClock(void *buf, size_t maxbytes)
+{
+    return 0;
+}
+
+static void
+GiveSystemInfo(void)
+{
+    long si;
+
+    /* This is not very good */
+    si = sysconf(_SC_CHILD_MAX);
+    RNG_RandomUpdate(&si, sizeof(si));
+}
+#endif
+#endif /* Sun */
+
+#if defined(__hpux)
+#include <sys/unistd.h>
+
+#define getdtablesize() sysconf(_SC_OPEN_MAX)
+
+#if defined(__ia64)
+#include <ia64/sys/inline.h>
+
+static size_t
+GetHighResClock(void *buf, size_t maxbytes)
+{
+    PRUint64 t;
+
+    t = _Asm_mov_from_ar(_AREG44);
+    return CopyLowBits(buf, maxbytes, &t, sizeof(t));
+}
+#else
+static size_t
+GetHighResClock(void *buf, size_t maxbytes)
+{
+    extern int ret_cr16();
+    int cr16val;
+
+    cr16val = ret_cr16();
+    return CopyLowBits(buf, maxbytes, &cr16val, sizeof(cr16val));
+}
+#endif
+
+static void
+GiveSystemInfo(void)
+{
+    long si;
+
+    /* This is not very good */
+    si = sysconf(_AES_OS_VERSION);
+    RNG_RandomUpdate(&si, sizeof(si));
+    si = sysconf(_SC_CPU_VERSION);
+    RNG_RandomUpdate(&si, sizeof(si));
+}
+#endif /* HPUX */
+
+#if defined(OSF1)
+#include <sys/types.h>
+#include <sys/sysinfo.h>
+#include <sys/systeminfo.h>
+#include <c_asm.h>
+
+static void
+GiveSystemInfo(void)
+{
+    char buf[BUFSIZ];
+    int rv;
+    int off = 0;
+
+    rv = sysinfo(SI_MACHINE, buf, sizeof(buf));
+    if (rv > 0) {
+	RNG_RandomUpdate(buf, rv);
+    }
+    rv = sysinfo(SI_RELEASE, buf, sizeof(buf));
+    if (rv > 0) {
+	RNG_RandomUpdate(buf, rv);
+    }
+    rv = sysinfo(SI_HW_SERIAL, buf, sizeof(buf));
+    if (rv > 0) {
+	RNG_RandomUpdate(buf, rv);
+    }
+}
+
+/*
+ * Use the "get the cycle counter" instruction on the alpha.
+ * The low 32 bits completely turn over in less than a minute.
+ * The high 32 bits are some non-counter gunk that changes sometimes.
+ */
+static size_t
+GetHighResClock(void *buf, size_t maxbytes)
+{
+    unsigned long t;
+
+    t = asm("rpcc %v0");
+    return CopyLowBits(buf, maxbytes, &t, sizeof(t));
+}
+
+#endif /* Alpha */
+
+#if defined(_IBMR2)
+static size_t
+GetHighResClock(void *buf, size_t maxbytes)
+{
+    return 0;
+}
+
+static void
+GiveSystemInfo(void)
+{
+    /* XXX haven't found any yet! */
+}
+#endif /* IBM R2 */
+
+#if defined(LINUX)
+#include <sys/sysinfo.h>
+
+static size_t
+GetHighResClock(void *buf, size_t maxbytes)
+{
+    return 0;
+}
+
+static void
+GiveSystemInfo(void)
+{
+#ifndef NO_SYSINFO
+    struct sysinfo si;
+    if (sysinfo(&si) == 0) {
+	RNG_RandomUpdate(&si, sizeof(si));
+    }
+#endif
+}
+#endif /* LINUX */
+
+#if defined(NCR)
+
+#include <sys/utsname.h>
+#include <sys/systeminfo.h>
+
+#define getdtablesize() sysconf(_SC_OPEN_MAX)
+
+static size_t
+GetHighResClock(void *buf, size_t maxbytes)
+{
+    return 0;
+}
+
+static void
+GiveSystemInfo(void)
+{
+    int rv;
+    char buf[2000];
+
+    rv = sysinfo(SI_MACHINE, buf, sizeof(buf));
+    if (rv > 0) {
+	RNG_RandomUpdate(buf, rv);
+    }
+    rv = sysinfo(SI_RELEASE, buf, sizeof(buf));
+    if (rv > 0) {
+	RNG_RandomUpdate(buf, rv);
+    }
+    rv = sysinfo(SI_HW_SERIAL, buf, sizeof(buf));
+    if (rv > 0) {
+	RNG_RandomUpdate(buf, rv);
+    }
+}
+
+#endif /* NCR */
+
+#if defined(sgi)
+#include <fcntl.h>
+#undef PRIVATE
+#include <sys/mman.h>
+#include <sys/syssgi.h>
+#include <sys/immu.h>
+#include <sys/systeminfo.h>
+#include <sys/utsname.h>
+#include <wait.h>
+
+static void
+GiveSystemInfo(void)
+{
+    int rv;
+    char buf[4096];
+
+    rv = syssgi(SGI_SYSID, &buf[0]);
+    if (rv > 0) {
+	RNG_RandomUpdate(buf, MAXSYSIDSIZE);
+    }
+#ifdef SGI_RDUBLK
+    rv = syssgi(SGI_RDUBLK, getpid(), &buf[0], sizeof(buf));
+    if (rv > 0) {
+	RNG_RandomUpdate(buf, sizeof(buf));
+    }
+#endif /* SGI_RDUBLK */
+    rv = syssgi(SGI_INVENT, SGI_INV_READ, buf, sizeof(buf));
+    if (rv > 0) {
+	RNG_RandomUpdate(buf, sizeof(buf));
+    }
+    rv = sysinfo(SI_MACHINE, buf, sizeof(buf));
+    if (rv > 0) {
+	RNG_RandomUpdate(buf, rv);
+    }
+    rv = sysinfo(SI_RELEASE, buf, sizeof(buf));
+    if (rv > 0) {
+	RNG_RandomUpdate(buf, rv);
+    }
+    rv = sysinfo(SI_HW_SERIAL, buf, sizeof(buf));
+    if (rv > 0) {
+	RNG_RandomUpdate(buf, rv);
+    }
+}
+
+static size_t GetHighResClock(void *buf, size_t maxbuf)
+{
+    unsigned phys_addr, raddr, cycleval;
+    static volatile unsigned *iotimer_addr = NULL;
+    static int tries = 0;
+    static int cntr_size;
+    int mfd;
+    long s0[2];
+    struct timeval tv;
+
+#ifndef SGI_CYCLECNTR_SIZE
+#define SGI_CYCLECNTR_SIZE      165     /* Size user needs to use to read CC */
+#endif
+
+    if (iotimer_addr == NULL) {
+	if (tries++ > 1) {
+	    /* Don't keep trying if it didn't work */
+	    return 0;
+	}
+
+	/*
+	** For SGI machines we can use the cycle counter, if it has one,
+	** to generate some truly random numbers
+	*/
+	phys_addr = syssgi(SGI_QUERY_CYCLECNTR, &cycleval);
+	if (phys_addr) {
+	    int pgsz = getpagesize();
+	    int pgoffmask = pgsz - 1;
+
+	    raddr = phys_addr & ~pgoffmask;
+	    mfd = open("/dev/mmem", O_RDONLY);
+	    if (mfd < 0) {
+		return 0;
+	    }
+	    iotimer_addr = (unsigned *)
+		mmap(0, pgoffmask, PROT_READ, MAP_PRIVATE, mfd, (int)raddr);
+	    if (iotimer_addr == (void*)-1) {
+		close(mfd);
+		iotimer_addr = NULL;
+		return 0;
+	    }
+	    iotimer_addr = (unsigned*)
+		((__psint_t)iotimer_addr | (phys_addr & pgoffmask));
+	    /*
+	     * The file 'mfd' is purposefully not closed.
+	     */
+	    cntr_size = syssgi(SGI_CYCLECNTR_SIZE);
+	    if (cntr_size < 0) {
+		struct utsname utsinfo;
+
+		/* 
+		 * We must be executing on a 6.0 or earlier system, since the
+		 * SGI_CYCLECNTR_SIZE call is not supported.
+		 * 
+		 * The only pre-6.1 platforms with 64-bit counters are
+		 * IP19 and IP21 (Challenge, PowerChallenge, Onyx).
+		 */
+		uname(&utsinfo);
+		if (!strncmp(utsinfo.machine, "IP19", 4) ||
+		    !strncmp(utsinfo.machine, "IP21", 4))
+			cntr_size = 64;
+		else
+			cntr_size = 32;
+	    }
+	    cntr_size /= 8;	/* Convert from bits to bytes */
+	}
+    }
+
+    s0[0] = *iotimer_addr;
+    if (cntr_size > 4)
+	s0[1] = *(iotimer_addr + 1);
+    memcpy(buf, (char *)&s0[0], cntr_size);
+    return CopyLowBits(buf, maxbuf, &s0, cntr_size);
+}
+#endif
+
+#if defined(sony)
+#include <sys/systeminfo.h>
+
+#define getdtablesize() sysconf(_SC_OPEN_MAX)
+
+static size_t
+GetHighResClock(void *buf, size_t maxbytes)
+{
+    return 0;
+}
+
+static void
+GiveSystemInfo(void)
+{
+    int rv;
+    char buf[2000];
+
+    rv = sysinfo(SI_MACHINE, buf, sizeof(buf));
+    if (rv > 0) {
+	RNG_RandomUpdate(buf, rv);
+    }
+    rv = sysinfo(SI_RELEASE, buf, sizeof(buf));
+    if (rv > 0) {
+	RNG_RandomUpdate(buf, rv);
+    }
+    rv = sysinfo(SI_HW_SERIAL, buf, sizeof(buf));
+    if (rv > 0) {
+	RNG_RandomUpdate(buf, rv);
+    }
+}
+#endif /* sony */
+
+#if defined(sinix)
+#include <sys/systeminfo.h>
+#include <sys/times.h>
+
+int gettimeofday(struct timeval *, struct timezone *);
+int gethostname(char *, int);
+
+#define getdtablesize() sysconf(_SC_OPEN_MAX)
+
+static size_t
+GetHighResClock(void *buf, size_t maxbytes)
+{
+    int ticks;
+    struct tms buffer;
+
+    ticks=times(&buffer);
+    return CopyLowBits(buf, maxbytes, &ticks, sizeof(ticks));
+}
+
+static void
+GiveSystemInfo(void)
+{
+    int rv;
+    char buf[2000];
+
+    rv = sysinfo(SI_MACHINE, buf, sizeof(buf));
+    if (rv > 0) {
+	RNG_RandomUpdate(buf, rv);
+    }
+    rv = sysinfo(SI_RELEASE, buf, sizeof(buf));
+    if (rv > 0) {
+	RNG_RandomUpdate(buf, rv);
+    }
+    rv = sysinfo(SI_HW_SERIAL, buf, sizeof(buf));
+    if (rv > 0) {
+	RNG_RandomUpdate(buf, rv);
+    }
+}
+#endif /* sinix */
+
+
+#ifdef BEOS
+#include <be/kernel/OS.h>
+
+static size_t
+GetHighResClock(void *buf, size_t maxbytes)
+{
+    bigtime_t bigtime; /* Actually a int64 */
+
+    bigtime = real_time_clock_usecs();
+    return CopyLowBits(buf, maxbytes, &bigtime, sizeof(bigtime));
+}
+
+static void
+GiveSystemInfo(void)
+{
+    system_info *info = NULL;
+    PRInt32 val;
+    get_system_info(info);
+    if (info) {
+        val = info->boot_time;
+        RNG_RandomUpdate(&val, sizeof(val));
+        val = info->used_pages;
+        RNG_RandomUpdate(&val, sizeof(val));
+        val = info->used_ports;
+        RNG_RandomUpdate(&val, sizeof(val));
+        val = info->used_threads;
+        RNG_RandomUpdate(&val, sizeof(val));
+        val = info->used_teams;
+        RNG_RandomUpdate(&val, sizeof(val));
+    }
+}
+#endif /* BEOS */
+
+#if defined(nec_ews)
+#include <sys/systeminfo.h>
+
+#define getdtablesize() sysconf(_SC_OPEN_MAX)
+
+static size_t
+GetHighResClock(void *buf, size_t maxbytes)
+{
+    return 0;
+}
+
+static void
+GiveSystemInfo(void)
+{
+    int rv;
+    char buf[2000];
+
+    rv = sysinfo(SI_MACHINE, buf, sizeof(buf));
+    if (rv > 0) {
+	RNG_RandomUpdate(buf, rv);
+    }
+    rv = sysinfo(SI_RELEASE, buf, sizeof(buf));
+    if (rv > 0) {
+	RNG_RandomUpdate(buf, rv);
+    }
+    rv = sysinfo(SI_HW_SERIAL, buf, sizeof(buf));
+    if (rv > 0) {
+	RNG_RandomUpdate(buf, rv);
+    }
+}
+#endif /* nec_ews */
+
+size_t RNG_GetNoise(void *buf, size_t maxbytes)
+{
+    struct timeval tv;
+    int n = 0;
+    int c;
+
+    n = GetHighResClock(buf, maxbytes);
+    maxbytes -= n;
+
+    (void)gettimeofday(&tv, 0);
+    c = CopyLowBits((char*)buf+n, maxbytes, &tv.tv_usec, sizeof(tv.tv_usec));
+    n += c;
+    maxbytes -= c;
+    c = CopyLowBits((char*)buf+n, maxbytes, &tv.tv_sec, sizeof(tv.tv_sec));
+    n += c;
+    return n;
+}
+
+#define SAFE_POPEN_MAXARGS	10	/* must be at least 2 */
+
+/*
+ * safe_popen is static to this module and we know what arguments it is
+ * called with. Note that this version only supports a single open child
+ * process at any time.
+ */
+static pid_t safe_popen_pid;
+static struct sigaction oldact;
+
+static FILE *
+safe_popen(char *cmd)
+{
+    int p[2], fd, argc;
+    pid_t pid;
+    char *argv[SAFE_POPEN_MAXARGS + 1];
+    FILE *fp;
+    static char blank[] = " \t";
+    static struct sigaction newact;
+
+    if (pipe(p) < 0)
+	return 0;
+
+    fp = fdopen(p[0], "r");
+    if (fp == 0) {
+	close(p[0]);
+	close(p[1]);
+	return 0;
+    }
+
+    /* Setup signals so that SIGCHLD is ignored as we want to do waitpid */
+    newact.sa_handler = SIG_DFL;
+    newact.sa_flags = 0;
+    sigfillset(&newact.sa_mask);
+    sigaction (SIGCHLD, &newact, &oldact);
+
+    pid = fork();
+    switch (pid) {
+      int ndesc;
+
+      case -1:
+	fclose(fp); /* this closes p[0], the fd associated with fp */
+	close(p[1]);
+	sigaction (SIGCHLD, &oldact, NULL);
+	return 0;
+
+      case 0:
+	/* dup write-side of pipe to stderr and stdout */
+	if (p[1] != 1) dup2(p[1], 1);
+	if (p[1] != 2) dup2(p[1], 2);
+
+	/* 
+	 * close the other file descriptors, except stdin which we
+	 * try reassociating with /dev/null, first (bug 174993)
+	 */
+	if (!freopen("/dev/null", "r", stdin))
+	    close(0);
+	ndesc = getdtablesize();
+	for (fd = PR_MIN(65536, ndesc); --fd > 2; close(fd));
+
+	/* clean up environment in the child process */
+	putenv("PATH=/bin:/usr/bin:/sbin:/usr/sbin:/etc:/usr/etc");
+	putenv("SHELL=/bin/sh");
+	putenv("IFS= \t");
+
+	/*
+	 * The caller may have passed us a string that is in text
+	 * space. It may be illegal to modify the string
+	 */
+	cmd = strdup(cmd);
+	/* format argv */
+	argv[0] = strtok(cmd, blank);
+	argc = 1;
+	while ((argv[argc] = strtok(0, blank)) != 0) {
+	    if (++argc == SAFE_POPEN_MAXARGS) {
+		argv[argc] = 0;
+		break;
+	    }
+	}
+
+	/* and away we go */
+	execvp(argv[0], argv);
+	exit(127);
+	break;
+
+      default:
+	close(p[1]);
+	break;
+    }
+
+    /* non-zero means there's a cmd running */
+    safe_popen_pid = pid;
+    return fp;
+}
+
+static int
+safe_pclose(FILE *fp)
+{
+    pid_t pid;
+    int status = -1, rv;
+
+    if ((pid = safe_popen_pid) == 0)
+	return -1;
+    safe_popen_pid = 0;
+
+    fclose(fp);
+
+    /* yield the processor so the child gets some time to exit normally */
+    PR_Sleep(PR_INTERVAL_NO_WAIT);
+
+    /* if the child hasn't exited, kill it -- we're done with its output */
+    while ((rv = waitpid(pid, &status, WNOHANG)) == -1 && errno == EINTR)
+	;
+    if (rv == 0) {
+	kill(pid, SIGKILL);
+	while ((rv = waitpid(pid, &status, 0)) == -1 && errno == EINTR)
+	    ;
+    }
+
+    /* Reset SIGCHLD signal hander before returning */
+    sigaction(SIGCHLD, &oldact, NULL);
+
+    return status;
+}
+
+#ifdef DARWIN
+#include <TargetConditionals.h>
+#if !TARGET_OS_IPHONE
+#include <crt_externs.h>
+#endif
+#endif
+
+/* Fork netstat to collect its output by default. Do not unset this unless
+ * another source of entropy is available
+ */
+#define DO_NETSTAT 1
+
+void RNG_SystemInfoForRNG(void)
+{
+    FILE *fp;
+    char buf[BUFSIZ];
+    size_t bytes;
+    const char * const *cp;
+    char *randfile;
+#ifdef DARWIN
+#if TARGET_OS_IPHONE
+    /* iOS does not expose a way to access environ. */
+    char **environ = NULL;
+#else
+    char **environ = *_NSGetEnviron();
+#endif
+#else
+    extern char **environ;
+#endif
+#ifdef BEOS
+    static const char * const files[] = {
+	"/boot/var/swap",
+	"/boot/var/log/syslog",
+	"/boot/var/tmp",
+	"/boot/home/config/settings",
+	"/boot/home",
+	0
+    };
+#else
+    static const char * const files[] = {
+	"/etc/passwd",
+	"/etc/utmp",
+	"/tmp",
+	"/var/tmp",
+	"/usr/tmp",
+	0
+    };
+#endif
+
+#if defined(BSDI)
+    static char netstat_ni_cmd[] = "netstat -nis";
+#else
+    static char netstat_ni_cmd[] = "netstat -ni";
+#endif
+
+    GiveSystemInfo();
+
+    bytes = RNG_GetNoise(buf, sizeof(buf));
+    RNG_RandomUpdate(buf, bytes);
+
+    /*
+     * Pass the C environment and the addresses of the pointers to the
+     * hash function. This makes the random number function depend on the
+     * execution environment of the user and on the platform the program
+     * is running on.
+     */
+    if (environ != NULL) {
+        cp = (const char * const *) environ;
+        while (*cp) {
+	    RNG_RandomUpdate(*cp, strlen(*cp));
+	    cp++;
+        }
+        RNG_RandomUpdate(environ, (char*)cp - (char*)environ);
+    }
+
+    /* Give in system information */
+    if (gethostname(buf, sizeof(buf)) == 0) {
+	RNG_RandomUpdate(buf, strlen(buf));
+    }
+    GiveSystemInfo();
+
+    /* grab some data from system's PRNG before any other files. */
+    bytes = RNG_FileUpdate("/dev/urandom", SYSTEM_RNG_SEED_COUNT);
+
+    /* If the user points us to a random file, pass it through the rng */
+    randfile = getenv("NSRANDFILE");
+    if ( ( randfile != NULL ) && ( randfile[0] != '\0') ) {
+	char *randCountString = getenv("NSRANDCOUNT");
+	int randCount = randCountString ? atoi(randCountString) : 0;
+	if (randCount != 0) {
+	    RNG_FileUpdate(randfile, randCount);
+	} else {
+	    RNG_FileForRNG(randfile);
+	}
+    }
+
+    /* pass other files through */
+    for (cp = files; *cp; cp++)
+	RNG_FileForRNG(*cp);
+
+/*
+ * Bug 100447: On BSD/OS 4.2 and 4.3, we have problem calling safe_popen
+ * in a pthreads environment.  Therefore, we call safe_popen last and on
+ * BSD/OS we do not call safe_popen when we succeeded in getting data
+ * from /dev/urandom.
+ *
+ * Bug 174993: On platforms providing /dev/urandom, don't fork netstat
+ * either, if data has been gathered successfully.
+ */
+
+#if defined(BSDI) || defined(FREEBSD) || defined(NETBSD) \
+    || defined(OPENBSD) || defined(DARWIN) || defined(LINUX) \
+    || defined(HPUX)
+    if (bytes == SYSTEM_RNG_SEED_COUNT)
+        return;
+
+    /*
+     * Modified to abort the process if it failed to read from /dev/urandom.
+     *
+     * See crbug.com/244661 for details.
+     */
+    fprintf(stderr, "[ERROR:%s(%d)] NSS read %zu bytes (expected %d bytes) "
+            "from /dev/urandom. Abort process.\n", __FILE__, __LINE__,
+            bytes, SYSTEM_RNG_SEED_COUNT);
+    fflush(stderr);
+    abort();
+#endif
+
+#ifdef SOLARIS
+
+/*
+ * On Solaris, NSS may be initialized automatically from libldap in
+ * applications that are unaware of the use of NSS. safe_popen forks, and
+ * sometimes creates issues with some applications' pthread_atfork handlers.
+ * We always have /dev/urandom on Solaris 9 and above as an entropy source,
+ * and for Solaris 8 we have the libkstat interface, so we don't need to
+ * fork netstat.
+ */
+
+#undef DO_NETSTAT
+    if (!bytes) {
+        /* On Solaris 8, /dev/urandom isn't available, so we use libkstat. */
+        PRUint32 kstat_bytes = 0;
+        if (SECSuccess != RNG_kstat(&kstat_bytes)) {
+            PORT_Assert(0);
+        }
+        bytes += kstat_bytes;
+        PORT_Assert(bytes);
+    }
+#endif
+
+#ifdef DO_NETSTAT
+    fp = safe_popen(netstat_ni_cmd);
+    if (fp != NULL) {
+	while ((bytes = fread(buf, 1, sizeof(buf), fp)) > 0)
+	    RNG_RandomUpdate(buf, bytes);
+	safe_pclose(fp);
+    }
+#endif
+
+}
+
+#define TOTAL_FILE_LIMIT 1000000	/* one million */
+
+size_t RNG_FileUpdate(const char *fileName, size_t limit)
+{
+    FILE *        file;
+    int           fd;
+    int           bytes;
+    size_t        fileBytes = 0;
+    struct stat   stat_buf;
+    unsigned char buffer[BUFSIZ];
+    static size_t totalFileBytes = 0;
+    
+    /* suppress valgrind warnings due to holes in struct stat */
+    memset(&stat_buf, 0, sizeof(stat_buf));
+
+    if (stat((char *)fileName, &stat_buf) < 0)
+	return fileBytes;
+    RNG_RandomUpdate(&stat_buf, sizeof(stat_buf));
+    
+    file = fopen(fileName, "r");
+    if (file != NULL) {
+	/* Read from the underlying file descriptor directly to bypass stdio
+	 * buffering and avoid reading more bytes than we need from
+	 * /dev/urandom. NOTE: we can't use fread with unbuffered I/O because
+	 * fread may return EOF in unbuffered I/O mode on Android.
+	 *
+	 * Moreover, we read into a buffer of size BUFSIZ, so buffered I/O
+	 * has no performance advantage. */
+	fd = fileno(file);
+	/* 'file' was just opened, so this should not fail. */
+	PORT_Assert(fd != -1);
+	while (limit > fileBytes) {
+	    bytes = PR_MIN(sizeof buffer, limit - fileBytes);
+	    bytes = read(fd, buffer, bytes);
+	    if (bytes <= 0)
+		break;
+	    RNG_RandomUpdate(buffer, bytes);
+	    fileBytes      += bytes;
+	    totalFileBytes += bytes;
+	    /* after TOTAL_FILE_LIMIT has been reached, only read in first
+	    ** buffer of data from each subsequent file.
+	    */
+	    if (totalFileBytes > TOTAL_FILE_LIMIT) 
+		break;
+	}
+	fclose(file);
+    }
+    /*
+     * Pass yet another snapshot of our highest resolution clock into
+     * the hash function.
+     */
+    bytes = RNG_GetNoise(buffer, sizeof(buffer));
+    RNG_RandomUpdate(buffer, bytes);
+    return fileBytes;
+}
+
+void RNG_FileForRNG(const char *fileName)
+{
+    RNG_FileUpdate(fileName, TOTAL_FILE_LIMIT);
+}
+
+void ReadSingleFile(const char *fileName)
+{
+    FILE *        file;
+    unsigned char buffer[BUFSIZ];
+    
+    file = fopen(fileName, "rb");
+    if (file != NULL) {
+	while (fread(buffer, 1, sizeof(buffer), file) > 0)
+	    ;
+	fclose(file);
+    } 
+}
+
+#define _POSIX_PTHREAD_SEMANTICS
+#include <dirent.h>
+
+PRBool
+ReadFileOK(char *dir, char *file)
+{
+    struct stat   stat_buf;
+    char filename[PATH_MAX];
+    int count = snprintf(filename, sizeof filename, "%s/%s",dir, file);
+
+    if (count <= 0) {
+	return PR_FALSE; /* name too long, can't read it anyway */
+    }
+    
+    if (stat(filename, &stat_buf) < 0)
+	return PR_FALSE; /* can't stat, probably can't read it then as well */
+    return S_ISREG(stat_buf.st_mode) ? PR_TRUE : PR_FALSE;
+}
+
+/*
+ * read one file out of either /etc or the user's home directory.
+ * fileToRead tells which file to read.
+ *
+ * return 1 if it's time to reset the fileToRead (no more files to read).
+ */
+int ReadOneFile(int fileToRead)
+{
+    char *dir = "/etc";
+    DIR *fd = opendir(dir);
+    int resetCount = 0;
+#ifdef SOLARIS
+     /* grumble, Solaris does not define struct dirent to be the full length */
+    typedef union {
+	unsigned char space[sizeof(struct dirent) + MAXNAMELEN];
+	struct dirent dir;
+    } dirent_hack;
+    dirent_hack entry, firstEntry;
+
+#define entry_dir entry.dir
+#else
+    struct dirent entry, firstEntry;
+#define entry_dir entry
+#endif
+
+    int i, error = -1;
+
+    if (fd == NULL) {
+	dir = getenv("HOME");
+	if (dir) {
+	    fd = opendir(dir);
+	}
+    }
+    if (fd == NULL) {
+	return 1;
+    }
+
+    for (i=0; i <= fileToRead; i++) {
+	struct dirent *result = NULL;
+	do {
+	    error = readdir_r(fd, &entry_dir, &result);
+	} while (error == 0 && result != NULL  &&
+					!ReadFileOK(dir,&result->d_name[0]));
+	if (error != 0 || result == NULL)  {
+	    resetCount = 1; /* read to the end, start again at the beginning */
+	    if (i != 0) {
+		/* ran out of entries in the directory, use the first one */
+	 	entry = firstEntry;
+	 	error = 0;
+	 	break;
+	    }
+	    /* if i== 0, there were no readable entries in the directory */
+	    break;
+	}
+	if (i==0) {
+	    /* save the first entry in case we run out of entries */
+	    firstEntry = entry;
+	}
+    }
+
+    if (error == 0) {
+	char filename[PATH_MAX];
+	int count = snprintf(filename, sizeof filename, 
+				"%s/%s",dir, &entry_dir.d_name[0]);
+	if (count >= 1) {
+	    ReadSingleFile(filename);
+	}
+    } 
+
+    closedir(fd);
+    return resetCount;
+}
+
+/*
+ * do something to try to introduce more noise into the 'GetNoise' call
+ */
+static void rng_systemJitter(void)
+{
+   static int fileToRead = 1;
+
+   if (ReadOneFile(fileToRead)) {
+	fileToRead = 1;
+   } else {
+	fileToRead++;
+   }
+}
+
+/*
+ * Modified to abort the process if it failed to read from /dev/urandom.
+ *
+ * See crbug.com/244661 for details.
+ */
+size_t RNG_SystemRNG(void *dest, size_t maxLen)
+{
+    FILE *file;
+    int fd;
+    int bytes;
+    size_t fileBytes = 0;
+    unsigned char *buffer = dest;
+
+    file = fopen("/dev/urandom", "r");
+    if (file == NULL) {
+	fprintf(stderr, "[ERROR:%s(%d)] NSS failed to read from /dev/urandom. "
+		"Abort process.\n", __FILE__, __LINE__);
+	fflush(stderr);
+	abort();
+    }
+    /* Read from the underlying file descriptor directly to bypass stdio
+     * buffering and avoid reading more bytes than we need from /dev/urandom.
+     * NOTE: we can't use fread with unbuffered I/O because fread may return
+     * EOF in unbuffered I/O mode on Android.
+     */
+    fd = fileno(file);
+    /* 'file' was just opened, so this should not fail. */
+    PORT_Assert(fd != -1);
+    while (maxLen > fileBytes) {
+	bytes = maxLen - fileBytes;
+	bytes = read(fd, buffer, bytes);
+	if (bytes <= 0)
+	    break;
+	fileBytes += bytes;
+	buffer += bytes;
+    }
+    fclose(file);
+    if (fileBytes != maxLen) {
+	fprintf(stderr, "[ERROR:%s(%d)] NSS failed to read from /dev/urandom. "
+		"Abort process.\n", __FILE__, __LINE__);
+	fflush(stderr);
+	abort();
+    }
+    return fileBytes;
+}