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diff --git a/cipher/rndunix.c b/cipher/rndunix.c
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+/****************************************************************************
+ * *
+ * *
+ * Unix Randomness-Gathering Code *
+ * *
+ * Copyright Peter Gutmann, Paul Kendall, and Chris Wedgwood 1996-1999. *
+ * Heavily modified for GnuPG by Werner Koch *
+ * *
+ * *
+ ****************************************************************************/
+
+/* This module is part of the cryptlib continuously seeded pseudorandom
+ number generator. For usage conditions, see lib_rand.c
+
+ [Here is the notice from lib_rand.c:]
+
+ This module and the misc/rnd*.c modules represent the cryptlib
+ continuously seeded pseudorandom number generator (CSPRNG) as described in
+ my 1998 Usenix Security Symposium paper "The generation of random numbers
+ for cryptographic purposes".
+
+ The CSPRNG code is copyright Peter Gutmann (and various others) 1996,
+ 1997, 1998, 1999, all rights reserved. Redistribution of the CSPRNG
+ modules 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
+ and this permission notice in its entirety.
+
+ 2. Redistributions in binary form must reproduce the copyright notice in
+ the documentation and/or other materials provided with the distribution.
+
+ 3. A copy of any bugfixes or enhancements made must be provided to the
+ author, <pgut001@cs.auckland.ac.nz> to allow them to be added to the
+ baseline version of the code.
+
+ ALTERNATIVELY, the code may be distributed under the terms of the GNU
+ General Public License, version 2 or any later version published by the
+ Free Software Foundation, in which case the provisions of the GNU GPL are
+ required INSTEAD OF the above restrictions.
+
+ Although not required under the terms of the GPL, it would still be nice if
+ you could make any changes available to the author to allow a consistent
+ code base to be maintained */
+
+
+
+/* General includes */
+
+#include <config.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <assert.h>
+
+/* OS-specific includes */
+
+#ifdef __osf__
+ /* Somewhere in the morass of system-specific cruft which OSF/1 pulls in
+ * via the following includes are various endianness defines, so we
+ * undefine the cryptlib ones, which aren't really needed for this module
+ * anyway */
+#undef BIG_ENDIAN
+#undef LITTLE_ENDIAN
+#endif /* __osf__ */
+
+#include <unistd.h>
+#include <fcntl.h>
+#include <pwd.h>
+#ifndef __QNX__
+#include <sys/errno.h>
+#include <sys/ipc.h>
+#endif /* __QNX__ */
+#include <sys/time.h> /* SCO and SunOS need this before resource.h */
+#ifndef __QNX__
+#include <sys/resource.h>
+#endif /* __QNX__ */
+#if defined( _AIX ) || defined( __QNX__ )
+#include <sys/select.h>
+#endif /* _AIX || __QNX__ */
+#ifndef __QNX__
+#include <sys/shm.h>
+#include <signal.h>
+#include <sys/signal.h>
+#endif /* __QNX__ */
+#include <sys/stat.h>
+#include <sys/types.h> /* Verschiedene komische Typen */
+#if defined( __hpux ) && ( OS_VERSION == 9 )
+#include <vfork.h>
+#endif /* __hpux 9.x, after that it's in unistd.h */
+#include <sys/wait.h>
+/* #include <kitchensink.h> */
+#ifdef __QNX__
+#include <signal.h>
+#include <process.h>
+#endif /* __QNX__ */
+#include <errno.h>
+
+#include "types.h" /* for byte and u32 typedefs */
+#include "algorithms.h"
+#include "util.h"
+
+#ifndef EAGAIN
+#define EAGAIN EWOULDBLOCK
+#endif
+#ifndef STDIN_FILENO
+#define STDIN_FILENO 0
+#endif
+#ifndef STDOUT_FILENO
+#define STDOUT_FILENO 1
+#endif
+
+#define GATHER_BUFSIZE 49152 /* Usually about 25K are filled */
+
+/* The structure containing information on random-data sources. Each
+ * record contains the source and a relative estimate of its usefulness
+ * (weighting) which is used to scale the number of kB of output from the
+ * source (total = data_bytes / usefulness). Usually the weighting is in the
+ * range 1-3 (or 0 for especially useless sources), resulting in a usefulness
+ * rating of 1...3 for each kB of source output (or 0 for the useless
+ * sources).
+ *
+ * If the source is constantly changing (certain types of network statistics
+ * have this characteristic) but the amount of output is small, the weighting
+ * is given as a negative value to indicate that the output should be treated
+ * as if a minimum of 1K of output had been obtained. If the source produces
+ * a lot of output then the scale factor is fractional, resulting in a
+ * usefulness rating of < 1 for each kB of source output.
+ *
+ * In order to provide enough randomness to satisfy the requirements for a
+ * slow poll, we need to accumulate at least 20 points of usefulness (a
+ * typical system should get about 30 points).
+ *
+ * Some potential options are missed out because of special considerations.
+ * pstat -i and pstat -f can produce amazing amounts of output (the record
+ * is 600K on an Oracle server) which floods the buffer and doesn't yield
+ * anything useful (apart from perhaps increasing the entropy of the vmstat
+ * output a bit), so we don't bother with this. pstat in general produces
+ * quite a bit of output, but it doesn't change much over time, so it gets
+ * very low weightings. netstat -s produces constantly-changing output but
+ * also produces quite a bit of it, so it only gets a weighting of 2 rather
+ * than 3. The same holds for netstat -in, which gets 1 rather than 2.
+ *
+ * Some binaries are stored in different locations on different systems so
+ * alternative paths are given for them. The code sorts out which one to
+ * run by itself, once it finds an exectable somewhere it moves on to the
+ * next source. The sources are arranged roughly in their order of
+ * usefulness, occasionally sources which provide a tiny amount of
+ * relatively useless data are placed ahead of ones which provide a large
+ * amount of possibly useful data because another 100 bytes can't hurt, and
+ * it means the buffer won't be swamped by one or two high-output sources.
+ * All the high-output sources are clustered towards the end of the list
+ * for this reason. Some binaries are checked for in a certain order, for
+ * example under Slowaris /usr/ucb/ps understands aux as an arg, but the
+ * others don't. Some systems have conditional defines enabling alternatives
+ * to commands which don't understand the usual options but will provide
+ * enough output (in the form of error messages) to look like they're the
+ * real thing, causing alternative options to be skipped (we can't check the
+ * return either because some commands return peculiar, non-zero status even
+ * when they're working correctly).
+ *
+ * In order to maximise use of the buffer, the code performs a form of run-
+ * length compression on its input where a repeated sequence of bytes is
+ * replaced by the occurrence count mod 256. Some commands output an awful
+ * lot of whitespace, this measure greatly increases the amount of data we
+ * can fit in the buffer.
+ *
+ * When we scale the weighting using the SC() macro, some preprocessors may
+ * give a division by zero warning for the most obvious expression
+ * 'weight ? 1024 / weight : 0' (and gcc 2.7.2.2 dies with a division by zero
+ * trap), so we define a value SC_0 which evaluates to zero when fed to
+ * '1024 / SC_0' */
+
+#define SC( weight ) ( 1024 / weight ) /* Scale factor */
+#define SC_0 16384 /* SC( SC_0 ) evalutes to 0 */
+
+static struct RI {
+ const char *path; /* Path to check for existence of source */
+ const char *arg; /* Args for source */
+ const int usefulness; /* Usefulness of source */
+ FILE *pipe; /* Pipe to source as FILE * */
+ int pipeFD; /* Pipe to source as FD */
+ pid_t pid; /* pid of child for waitpid() */
+ int length; /* Quantity of output produced */
+ const int hasAlternative; /* Whether source has alt.location */
+} dataSources[] = {
+
+ { "/bin/vmstat", "-s", SC(-3), NULL, 0, 0, 0, 1 },
+ { "/usr/bin/vmstat", "-s", SC(-3), NULL, 0, 0, 0, 0},
+ { "/bin/vmstat", "-c", SC(-3), NULL, 0, 0, 0, 1 },
+ { "/usr/bin/vmstat", "-c", SC(-3), NULL, 0, 0, 0, 0},
+ { "/usr/bin/pfstat", NULL, SC(-2), NULL, 0, 0, 0, 0},
+ { "/bin/vmstat", "-i", SC(-2), NULL, 0, 0, 0, 1 },
+ { "/usr/bin/vmstat", "-i", SC(-2), NULL, 0, 0, 0, 0},
+ { "/usr/ucb/netstat", "-s", SC(2), NULL, 0, 0, 0, 1 },
+ { "/usr/bin/netstat", "-s", SC(2), NULL, 0, 0, 0, 1 },
+ { "/usr/sbin/netstat", "-s", SC(2), NULL, 0, 0, 0, 1},
+ { "/usr/etc/netstat", "-s", SC(2), NULL, 0, 0, 0, 0},
+ { "/usr/bin/nfsstat", NULL, SC(2), NULL, 0, 0, 0, 0},
+ { "/usr/ucb/netstat", "-m", SC(-1), NULL, 0, 0, 0, 1 },
+ { "/usr/bin/netstat", "-m", SC(-1), NULL, 0, 0, 0, 1 },
+ { "/usr/sbin/netstat", "-m", SC(-1), NULL, 0, 0, 0, 1 },
+ { "/usr/etc/netstat", "-m", SC(-1), NULL, 0, 0, 0, 0 },
+ { "/bin/netstat", "-in", SC(-1), NULL, 0, 0, 0, 1 },
+ { "/usr/ucb/netstat", "-in", SC(-1), NULL, 0, 0, 0, 1 },
+ { "/usr/bin/netstat", "-in", SC(-1), NULL, 0, 0, 0, 1 },
+ { "/usr/sbin/netstat", "-in", SC(-1), NULL, 0, 0, 0, 1},
+ { "/usr/etc/netstat", "-in", SC(-1), NULL, 0, 0, 0, 0},
+ { "/usr/sbin/snmp_request", "localhost public get 1.3.6.1.2.1.7.1.0",
+ SC(-1), NULL, 0, 0, 0, 0 }, /* UDP in */
+ { "/usr/sbin/snmp_request", "localhost public get 1.3.6.1.2.1.7.4.0",
+ SC(-1), NULL, 0, 0, 0, 0 }, /* UDP out */
+ { "/usr/sbin/snmp_request", "localhost public get 1.3.6.1.2.1.4.3.0",
+ SC(-1), NULL, 0, 0, 0, 0 }, /* IP ? */
+ { "/usr/sbin/snmp_request", "localhost public get 1.3.6.1.2.1.6.10.0",
+ SC(-1), NULL, 0, 0, 0, 0 }, /* TCP ? */
+ { "/usr/sbin/snmp_request", "localhost public get 1.3.6.1.2.1.6.11.0",
+ SC(-1), NULL, 0, 0, 0, 0 }, /* TCP ? */
+ { "/usr/sbin/snmp_request", "localhost public get 1.3.6.1.2.1.6.13.0",
+ SC(-1), NULL, 0, 0, 0, 0 }, /* TCP ? */
+ { "/usr/bin/mpstat", NULL, SC(1), NULL, 0, 0, 0, 0 },
+ { "/usr/bin/w", NULL, SC(1), NULL, 0, 0, 0, 1 },
+ { "/usr/bsd/w", NULL, SC(1), NULL, 0, 0, 0, 0 },
+ { "/usr/bin/df", NULL, SC(1), NULL, 0, 0, 0, 1 },
+ { "/bin/df", NULL, SC(1), NULL, 0, 0, 0, 0 },
+ { "/usr/sbin/portstat", NULL, SC(1), NULL, 0, 0, 0, 0 },
+ { "/usr/bin/iostat", NULL, SC(SC_0), NULL, 0, 0, 0, 0 },
+ { "/usr/bin/uptime", NULL, SC(SC_0), NULL, 0, 0, 0, 1 },
+ { "/usr/bsd/uptime", NULL, SC(SC_0), NULL, 0, 0, 0, 0 },
+ { "/bin/vmstat", "-f", SC(SC_0), NULL, 0, 0, 0, 1 },
+ { "/usr/bin/vmstat", "-f", SC(SC_0), NULL, 0, 0, 0, 0 },
+ { "/bin/vmstat", NULL, SC(SC_0), NULL, 0, 0, 0, 1 },
+ { "/usr/bin/vmstat", NULL, SC(SC_0), NULL, 0, 0, 0, 0 },
+ { "/usr/ucb/netstat", "-n", SC(0.5), NULL, 0, 0, 0, 1 },
+ { "/usr/bin/netstat", "-n", SC(0.5), NULL, 0, 0, 0, 1 },
+ { "/usr/sbin/netstat", "-n", SC(0.5), NULL, 0, 0, 0, 1 },
+ { "/usr/etc/netstat", "-n", SC(0.5), NULL, 0, 0, 0, 0 },
+#if defined( __sgi ) || defined( __hpux )
+ { "/bin/ps", "-el", SC(0.3), NULL, 0, 0, 0, 1 },
+#endif /* __sgi || __hpux */
+ { "/usr/ucb/ps", "aux", SC(0.3), NULL, 0, 0, 0, 1 },
+ { "/usr/bin/ps", "aux", SC(0.3), NULL, 0, 0, 0, 1 },
+ { "/bin/ps", "aux", SC(0.3), NULL, 0, 0, 0, 0 },
+ { "/bin/ps", "-A", SC(0.3), NULL, 0, 0, 0, 0 }, /*QNX*/
+ { "/usr/bin/ipcs", "-a", SC(0.5), NULL, 0, 0, 0, 1 },
+ { "/bin/ipcs", "-a", SC(0.5), NULL, 0, 0, 0, 0 },
+ /* Unreliable source, depends on system usage */
+ { "/etc/pstat", "-p", SC(0.5), NULL, 0, 0, 0, 1 },
+ { "/bin/pstat", "-p", SC(0.5), NULL, 0, 0, 0, 0 },
+ { "/etc/pstat", "-S", SC(0.2), NULL, 0, 0, 0, 1 },
+ { "/bin/pstat", "-S", SC(0.2), NULL, 0, 0, 0, 0 },
+ { "/etc/pstat", "-v", SC(0.2), NULL, 0, 0, 0, 1 },
+ { "/bin/pstat", "-v", SC(0.2), NULL, 0, 0, 0, 0 },
+ { "/etc/pstat", "-x", SC(0.2), NULL, 0, 0, 0, 1 },
+ { "/bin/pstat", "-x", SC(0.2), NULL, 0, 0, 0, 0 },
+ { "/etc/pstat", "-t", SC(0.1), NULL, 0, 0, 0, 1 },
+ { "/bin/pstat", "-t", SC(0.1), NULL, 0, 0, 0, 0 },
+ /* pstat is your friend */
+ { "/usr/bin/last", "-n 50", SC(0.3), NULL, 0, 0, 0, 1 },
+#ifdef __sgi
+ { "/usr/bsd/last", "-50", SC(0.3), NULL, 0, 0, 0, 0 },
+#endif /* __sgi */
+#ifdef __hpux
+ { "/etc/last", "-50", SC(0.3), NULL, 0, 0, 0, 0 },
+#endif /* __hpux */
+ { "/usr/bsd/last", "-n 50", SC(0.3), NULL, 0, 0, 0, 0 },
+ { "/usr/sbin/snmp_request", "localhost public get 1.3.6.1.2.1.5.1.0",
+ SC(0.1), NULL, 0, 0, 0, 0 }, /* ICMP ? */
+ { "/usr/sbin/snmp_request", "localhost public get 1.3.6.1.2.1.5.3.0",
+ SC(0.1), NULL, 0, 0, 0, 0 }, /* ICMP ? */
+ { "/etc/arp", "-a", SC(0.1), NULL, 0, 0, 0, 1 },
+ { "/usr/etc/arp", "-a", SC(0.1), NULL, 0, 0, 0, 1 },
+ { "/usr/bin/arp", "-a", SC(0.1), NULL, 0, 0, 0, 1 },
+ { "/usr/sbin/arp", "-a", SC(0.1), NULL, 0, 0, 0, 0 },
+ { "/usr/sbin/ripquery", "-nw 1 127.0.0.1",
+ SC(0.1), NULL, 0, 0, 0, 0 },
+ { "/bin/lpstat", "-t", SC(0.1), NULL, 0, 0, 0, 1 },
+ { "/usr/bin/lpstat", "-t", SC(0.1), NULL, 0, 0, 0, 1 },
+ { "/usr/ucb/lpstat", "-t", SC(0.1), NULL, 0, 0, 0, 0 },
+ { "/usr/bin/tcpdump", "-c 5 -efvvx", SC(1), NULL, 0, 0, 0, 0 },
+ /* This is very environment-dependant. If network traffic is low, it'll
+ * probably time out before delivering 5 packets, which is OK because
+ * it'll probably be fixed stuff like ARP anyway */
+ { "/usr/sbin/advfsstat", "-b usr_domain",
+ SC(SC_0), NULL, 0, 0, 0, 0},
+ { "/usr/sbin/advfsstat", "-l 2 usr_domain",
+ SC(0.5), NULL, 0, 0, 0, 0},
+ { "/usr/sbin/advfsstat", "-p usr_domain",
+ SC(SC_0), NULL, 0, 0, 0, 0},
+ /* This is a complex and screwball program. Some systems have things
+ * like rX_dmn, x = integer, for RAID systems, but the statistics are
+ * pretty dodgy */
+#ifdef __QNXNTO__
+ { "/bin/pidin", "-F%A%B%c%d%E%I%J%K%m%M%n%N%p%P%S%s%T", SC(0.3),
+ NULL, 0, 0, 0, 0 },
+#endif
+#if 0
+ /* The following aren't enabled since they're somewhat slow and not very
+ * unpredictable, however they give an indication of the sort of sources
+ * you can use (for example the finger might be more useful on a
+ * firewalled internal network) */
+ { "/usr/bin/finger", "@ml.media.mit.edu", SC(0.9), NULL, 0, 0, 0, 0 },
+ { "/usr/local/bin/wget", "-O - http://lavarand.sgi.com/block.html",
+ SC(0.9), NULL, 0, 0, 0, 0 },
+ { "/bin/cat", "/usr/spool/mqueue/syslog", SC(0.9), NULL, 0, 0, 0, 0 },
+#endif /* 0 */
+ { NULL, NULL, 0, NULL, 0, 0, 0, 0 }
+};
+
+static byte *gather_buffer; /* buffer for gathering random noise */
+static int gather_buffer_size; /* size of the memory buffer */
+static uid_t gatherer_uid;
+
+/* The message structure used to communicate with the parent */
+typedef struct {
+ int usefulness; /* usefulness of data */
+ int ndata; /* valid bytes in data */
+ char data[500]; /* gathered data */
+} GATHER_MSG;
+
+
+#ifndef HAVE_WAITPID
+pid_t
+waitpid(pid_t pid, int *statptr, int options)
+{
+#ifdef HAVE_WAIT4
+ return wait4(pid, statptr, options, NULL);
+#else
+ /* If wait4 is also not available, try wait3 for SVR3 variants */
+ /* Less ideal because can't actually request a specific pid */
+ /* For that reason, first check to see if pid is for an */
+ /* existing process. */
+ int tmp_pid, dummystat;;
+ if (kill(pid, 0) == -1) {
+ errno = ECHILD;
+ return -1;
+ }
+ if (statptr == NULL)
+ statptr = &dummystat;
+ while (((tmp_pid = wait3(statptr, options, 0)) != pid) &&
+ (tmp_pid != -1) && (tmp_pid != 0) && (pid != -1))
+ ;
+ return tmp_pid;
+#endif
+}
+#endif
+
+
+/* Under SunOS popen() doesn't record the pid of the child process. When
+ * pclose() is called, instead of calling waitpid() for the correct child, it
+ * calls wait() repeatedly until the right child is reaped. The problem is
+ * that this reaps any other children that happen to have died at that
+ * moment, and when their pclose() comes along, the process hangs forever.
+ * The fix is to use a wrapper for popen()/pclose() which saves the pid in
+ * the dataSources structure (code adapted from GNU-libc's popen() call).
+ *
+ * Aut viam inveniam aut faciam */
+
+static FILE *
+my_popen(struct RI *entry)
+{
+
+ int pipedes[2];
+ FILE *stream;
+
+ /* Create the pipe */
+ if (pipe(pipedes) < 0)
+ return (NULL);
+
+ /* Fork off the child ("vfork() is like an OS orgasm. All OS's want to
+ * do it, but most just end up faking it" - Chris Wedgwood). If your OS
+ * supports it, you should try to use vfork() here because it's somewhat
+ * more efficient */
+#if defined( sun ) || defined( __ultrix__ ) || defined( __osf__ ) || \
+ defined(__hpux)
+ entry->pid = vfork();
+#else /* */
+ entry->pid = fork();
+#endif /* Unixen which have vfork() */
+ if (entry->pid == (pid_t) - 1) {
+ /* The fork failed */
+ close(pipedes[0]);
+ close(pipedes[1]);
+ return (NULL);
+ }
+
+ if (entry->pid == (pid_t) 0) {
+ struct passwd *passwd;
+ int fd;
+
+ /* We are the child. Make the read side of the pipe be stdout */
+ if (dup2(pipedes[STDOUT_FILENO], STDOUT_FILENO) < 0)
+ exit(127);
+ /* Connect the other standard handles to the bit bucket. */
+ if ((fd = open ("/dev/null", O_RDWR)) != -1) {
+ dup2 (fd, STDIN_FILENO);
+ dup2 (fd, STDERR_FILENO);
+ close (fd);
+ }
+
+ /* Now that everything is set up, give up our permissions to make
+ * sure we don't read anything sensitive. If the getpwnam() fails,
+ * we default to -1, which is usually nobody */
+ if (gatherer_uid == (uid_t)-1 && \
+ (passwd = getpwnam("nobody")) != NULL)
+ gatherer_uid = passwd->pw_uid;
+
+ setuid(gatherer_uid);
+
+ /* Close the pipe descriptors. */
+ close(pipedes[STDIN_FILENO]);
+ close(pipedes[STDOUT_FILENO]);
+
+ /* Try and exec the program */
+ execl(entry->path, entry->path, entry->arg, NULL);
+
+ /* Die if the exec failed */
+ exit(127);
+ }
+
+ /* We are the parent. Close the irrelevant side of the pipe and open
+ * the relevant side as a new stream. Mark our side of the pipe to
+ * close on exec, so new children won't see it */
+ close(pipedes[STDOUT_FILENO]);
+
+#ifdef FD_CLOEXEC
+ fcntl(pipedes[STDIN_FILENO], F_SETFD, FD_CLOEXEC);
+#endif
+
+ stream = fdopen(pipedes[STDIN_FILENO], "r");
+
+ if (stream == NULL) {
+ int savedErrno = errno;
+
+ /* The stream couldn't be opened or the child structure couldn't be
+ * allocated. Kill the child and close the other side of the pipe */
+ kill(entry->pid, SIGKILL);
+ if (stream == NULL)
+ close(pipedes[STDOUT_FILENO]);
+ else
+ fclose(stream);
+
+ waitpid(entry->pid, NULL, 0);
+
+ entry->pid = 0;
+ errno = savedErrno;
+ return (NULL);
+ }
+
+ return (stream);
+}
+
+static int
+my_pclose(struct RI *entry)
+{
+ int status = 0;
+
+ if (fclose(entry->pipe))
+ return (-1);
+
+ /* We ignore the return value from the process because some programs
+ * return funny values which would result in the input being discarded
+ * even if they executed successfully. This isn't a problem because the
+ * result data size threshold will filter out any programs which exit
+ * with a usage message without producing useful output */
+ if (waitpid(entry->pid, NULL, 0) != entry->pid)
+ status = -1;
+
+ entry->pipe = NULL;
+ entry->pid = 0;
+ return (status);
+}
+
+
+/* Unix slow poll (without special support for Linux)
+ *
+ * If a few of the randomness sources create a large amount of output then
+ * the slowPoll() stops once the buffer has been filled (but before all the
+ * randomness sources have been sucked dry) so that the 'usefulness' factor
+ * remains below the threshold. For this reason the gatherer buffer has to
+ * be fairly sizeable on moderately loaded systems. This is something of a
+ * bug since the usefulness should be influenced by the amount of output as
+ * well as the source type */
+
+
+static int
+slow_poll(FILE *dbgfp, int dbgall, size_t *nbytes )
+{
+ int moreSources;
+ struct timeval tv;
+ fd_set fds;
+#if defined( __hpux )
+ size_t maxFD = 0;
+#else
+ int maxFD = 0;
+#endif /* OS-specific brokenness */
+ int bufPos, i, usefulness = 0;
+
+
+ /* Fire up each randomness source */
+ FD_ZERO(&fds);
+ for (i = 0; dataSources[i].path != NULL; i++) {
+ /* Since popen() is a fairly heavy function, we check to see whether
+ * the executable exists before we try to run it */
+ if (access(dataSources[i].path, X_OK)) {
+ if( dbgfp && dbgall )
+ fprintf(dbgfp, "%s not present%s\n", dataSources[i].path,
+ dataSources[i].hasAlternative ?
+ ", has alternatives" : "");
+ dataSources[i].pipe = NULL;
+ }
+ else
+ dataSources[i].pipe = my_popen(&dataSources[i]);
+
+ if (dataSources[i].pipe != NULL) {
+ dataSources[i].pipeFD = fileno(dataSources[i].pipe);
+ if (dataSources[i].pipeFD > maxFD)
+ maxFD = dataSources[i].pipeFD;
+#ifdef O_NONBLOCK /* Ohhh what a hack (used for Atari) */
+ fcntl(dataSources[i].pipeFD, F_SETFL, O_NONBLOCK);
+#endif
+ FD_SET(dataSources[i].pipeFD, &fds);
+ dataSources[i].length = 0;
+
+ /* If there are alternatives for this command, don't try and
+ * execute them */
+ while (dataSources[i].hasAlternative) {
+ if( dbgfp && dbgall )
+ fprintf(dbgfp, "Skipping %s\n", dataSources[i + 1].path);
+ i++;
+ }
+ }
+ }
+
+
+ /* Suck all the data we can get from each of the sources */
+ bufPos = 0;
+ moreSources = 1;
+ while (moreSources && bufPos <= gather_buffer_size) {
+ /* Wait for data to become available from any of the sources, with a
+ * timeout of 10 seconds. This adds even more randomness since data
+ * becomes available in a nondeterministic fashion. Kudos to HP's QA
+ * department for managing to ship a select() which breaks its own
+ * prototype */
+ tv.tv_sec = 10;
+ tv.tv_usec = 0;
+
+#if defined( __hpux ) && ( OS_VERSION == 9 )
+ if (select(maxFD + 1, (int *)&fds, NULL, NULL, &tv) == -1)
+#else /* */
+ if (select(maxFD + 1, &fds, NULL, NULL, &tv) == -1)
+#endif /* __hpux */
+ break;
+
+ /* One of the sources has data available, read it into the buffer */
+ for (i = 0; dataSources[i].path != NULL; i++) {
+ if( dataSources[i].pipe && FD_ISSET(dataSources[i].pipeFD, &fds)) {
+ size_t noBytes;
+
+ if ((noBytes = fread(gather_buffer + bufPos, 1,
+ gather_buffer_size - bufPos,
+ dataSources[i].pipe)) == 0) {
+ if (my_pclose(&dataSources[i]) == 0) {
+ int total = 0;
+
+ /* Try and estimate how much entropy we're getting
+ * from a data source */
+ if (dataSources[i].usefulness) {
+ if (dataSources[i].usefulness < 0)
+ total = (dataSources[i].length + 999)
+ / -dataSources[i].usefulness;
+ else
+ total = dataSources[i].length
+ / dataSources[i].usefulness;
+ }
+ if( dbgfp )
+ fprintf(dbgfp,
+ "%s %s contributed %d bytes, "
+ "usefulness = %d\n", dataSources[i].path,
+ (dataSources[i].arg != NULL) ?
+ dataSources[i].arg : "",
+ dataSources[i].length, total);
+ if( dataSources[i].length )
+ usefulness += total;
+ }
+ dataSources[i].pipe = NULL;
+ }
+ else {
+ int currPos = bufPos;
+ int endPos = bufPos + noBytes;
+
+ /* Run-length compress the input byte sequence */
+ while (currPos < endPos) {
+ int ch = gather_buffer[currPos];
+
+ /* If it's a single byte, just copy it over */
+ if (ch != gather_buffer[currPos + 1]) {
+ gather_buffer[bufPos++] = ch;
+ currPos++;
+ }
+ else {
+ int count = 0;
+
+ /* It's a run of repeated bytes, replace them
+ * with the byte count mod 256 */
+ while ((ch == gather_buffer[currPos])
+ && currPos < endPos) {
+ count++;
+ currPos++;
+ }
+ gather_buffer[bufPos++] = count;
+ noBytes -= count - 1;
+ }
+ }
+
+ /* Remember the number of (compressed) bytes of input we
+ * obtained */
+ dataSources[i].length += noBytes;
+ }
+ }
+ }
+
+ /* Check if there is more input available on any of the sources */
+ moreSources = 0;
+ FD_ZERO(&fds);
+ for (i = 0; dataSources[i].path != NULL; i++) {
+ if (dataSources[i].pipe != NULL) {
+ FD_SET(dataSources[i].pipeFD, &fds);
+ moreSources = 1;
+ }
+ }
+ }
+
+ if( dbgfp ) {
+ fprintf(dbgfp, "Got %d bytes, usefulness = %d\n", bufPos, usefulness);
+ fflush(dbgfp);
+ }
+ *nbytes = bufPos;
+ return usefulness;
+}
+
+/****************
+ * Start the gatherer process which writes messages of
+ * type GATHERER_MSG to pipedes
+ */
+static void
+start_gatherer( int pipefd )
+{
+ FILE *dbgfp = NULL;
+ int dbgall;
+
+#ifdef ENABLE_SELINUX_HACKS
+ /* We don't allow writing to the log file because this might be
+ sued to corrupt a secured file. Given that this is used as a
+ library by the ../g10/ code, we can't access the check function
+ from ../g10/misc.c. */
+ dbgall = 0;
+#else
+ {
+ const char *s = getenv("GNUPG_RNDUNIX_DBG");
+ if( s ) {
+ dbgfp = (*s=='-' && !s[1])? stdout : fopen(s, "a");
+ if( !dbgfp )
+ g10_log_info("can't open debug file `%s': %s\n",
+ s, strerror(errno) );
+ else
+ fprintf(dbgfp,"\nSTART RNDUNIX DEBUG pid=%d\n", (int)getpid());
+ }
+ dbgall = !!getenv("GNUPG_RNDUNIX_DBGALL");
+ }
+#endif
+
+ /* Set up the buffer */
+ gather_buffer_size = GATHER_BUFSIZE;
+ gather_buffer = malloc( gather_buffer_size );
+ if( !gather_buffer ) {
+ g10_log_error("out of core while allocating the gatherer buffer\n");
+ exit(2);
+ }
+
+ /* Reset the SIGC(H)LD handler to the system default. This is necessary
+ * because if the program which cryptlib is a part of installs its own
+ * SIGC(H)LD handler, it will end up reaping the cryptlib children before
+ * cryptlib can. As a result, my_pclose() will call waitpid() on a
+ * process which has already been reaped by the installed handler and
+ * return an error, so the read data won't be added to the randomness
+ * pool. There are two types of SIGC(H)LD naming, the SysV SIGCLD and
+ * the BSD/Posix SIGCHLD, so we need to handle either possibility */
+#ifdef SIGCLD
+ signal(SIGCLD, SIG_DFL);
+#else
+ signal(SIGCHLD, SIG_DFL);
+#endif
+
+ fflush (stderr);
+ /* Arrghh!! It's Stuart code!! */
+ /* (close all files but the ones we need) */
+ { int nmax, n1, i;
+#ifdef _SC_OPEN_MAX
+ if( (nmax=sysconf( _SC_OPEN_MAX )) < 0 ) {
+#ifdef _POSIX_OPEN_MAX
+ nmax = _POSIX_OPEN_MAX;
+#else
+ nmax = 20; /* assume a reasonable value */
+#endif
+ }
+#else
+ nmax = 20; /* assume a reasonable value */
+#endif
+ {
+ int fd;
+ if ((fd = open ("/dev/null", O_RDWR)) != -1) {
+ dup2 (fd, STDIN_FILENO);
+ dup2 (fd, STDOUT_FILENO);
+ dup2 (fd, STDERR_FILENO);
+ close (fd);
+ }
+ }
+ n1 = dbgfp? fileno (dbgfp) : -1;
+ for(i=0; i < nmax; i++ ) {
+ if (i != STDIN_FILENO && i != STDOUT_FILENO && i != STDERR_FILENO
+ && i != n1 && i != pipefd )
+ close(i);
+ }
+ errno = 0;
+ }
+
+
+ for(;;) {
+ GATHER_MSG msg;
+ size_t nbytes;
+ const char *p;
+
+ msg.usefulness = slow_poll( dbgfp, dbgall, &nbytes );
+ p = gather_buffer;
+ while( nbytes ) {
+ msg.ndata = nbytes > sizeof(msg.data)? sizeof(msg.data) : nbytes;
+ memcpy( msg.data, p, msg.ndata );
+ nbytes -= msg.ndata;
+ p += msg.ndata;
+
+ while( write( pipefd, &msg, sizeof(msg) ) != sizeof(msg) ) {
+ if( errno == EINTR )
+ continue;
+ if( errno == EAGAIN ) {
+ struct timeval tv;
+ tv.tv_sec = 0;
+ tv.tv_usec = 50000;
+ select(0, NULL, NULL, NULL, &tv);
+ continue;
+ }
+ if( errno == EPIPE ) /* parent has exited, so give up */
+ exit(0);
+
+ /* we can't do very much here because stderr is closed */
+ if( dbgfp )
+ fprintf(dbgfp, "gatherer can't write to pipe: %s\n",
+ strerror(errno) );
+ /* we start a new poll to give the system some time */
+ nbytes = 0;
+ break;
+ }
+ }
+ }
+ /* we are killed when the parent dies */
+}
+
+
+static int
+read_a_msg( int fd, GATHER_MSG *msg )
+{
+ char *buffer = (char*)msg;
+ size_t length = sizeof( *msg );
+ int n;
+
+ do {
+ do {
+ n = read(fd, buffer, length );
+ } while( n == -1 && errno == EINTR );
+ if( n == -1 )
+ return -1;
+ buffer += n;
+ length -= n;
+ } while( length );
+ return 0;
+}
+
+
+/****************
+ * Using a level of 0 should never block and better add nothing
+ * to the pool. So this is just a dummy for this gatherer.
+ */
+int
+rndunix_gather_random( void (*add)(const void*, size_t, int), int requester,
+ size_t length, int level )
+{
+ static pid_t gatherer_pid = 0;
+ static int pipedes[2];
+ GATHER_MSG msg;
+ size_t n;
+
+ if( !level )
+ return 0;
+
+ if( !gatherer_pid ) {
+ /* make sure we are not setuid */
+ if( getuid() != geteuid() )
+ BUG();
+ /* time to start the gatherer process */
+ if( pipe( pipedes ) ) {
+ g10_log_error("pipe() failed: %s\n", strerror(errno));
+ return -1;
+ }
+ gatherer_pid = fork();
+ if( gatherer_pid == -1 ) {
+ g10_log_error("can't for gatherer process: %s\n", strerror(errno));
+ return -1;
+ }
+ if( !gatherer_pid ) {
+ start_gatherer( pipedes[1] );
+ /* oops, can't happen */
+ return -1;
+ }
+ }
+
+ /* now read from the gatherer */
+ while( length ) {
+ int goodness;
+ ulong subtract;
+
+ if( read_a_msg( pipedes[0], &msg ) ) {
+ g10_log_error("reading from gatherer pipe failed: %s\n",
+ strerror(errno));
+ return -1;
+ }
+
+
+ if( level > 1 ) {
+ if( msg.usefulness > 30 )
+ goodness = 100;
+ else if ( msg.usefulness )
+ goodness = msg.usefulness * 100 / 30;
+ else
+ goodness = 0;
+ }
+ else if( level ) {
+ if( msg.usefulness > 15 )
+ goodness = 100;
+ else if ( msg.usefulness )
+ goodness = msg.usefulness * 100 / 15;
+ else
+ goodness = 0;
+ }
+ else
+ goodness = 100; /* goodness of level 0 is always 100 % */
+
+ n = msg.ndata;
+ if( n > length )
+ n = length;
+ (*add)( msg.data, n, requester );
+
+ /* this is the trick how e cope with the goodness */
+ subtract = (ulong)n * goodness / 100;
+ /* subtract at least 1 byte to avoid infinite loops */
+ length -= subtract ? subtract : 1;
+ }
+
+ return 0;
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-22 06:32:34 +0000