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-rw-r--r--comm/third_party/libgcrypt/src/gcryptrnd.c680
1 files changed, 680 insertions, 0 deletions
diff --git a/comm/third_party/libgcrypt/src/gcryptrnd.c b/comm/third_party/libgcrypt/src/gcryptrnd.c
new file mode 100644
index 0000000000..b13931b6e8
--- /dev/null
+++ b/comm/third_party/libgcrypt/src/gcryptrnd.c
@@ -0,0 +1,680 @@
+/* gcryptrnd.c - Libgcrypt Random Number Daemon
+ * Copyright (C) 2006 Free Software Foundation, Inc.
+ *
+ * Gcryptend is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License,
+ * or (at your option) any later version.
+ *
+ * Gcryptrnd is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+/* We require vsyslog pth
+ We need to test for: setrlimit
+
+ We should also prioritize requests. This is best done by putting
+ the requests into queues and have a main thread processing these
+ queues.
+
+ */
+
+#include <config.h>
+#include <stdio.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <assert.h>
+#include <time.h>
+#include <sys/times.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <stdarg.h>
+#include <syslog.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <unistd.h>
+#include <errno.h>
+#include <pth.h>
+#include <gcrypt.h>
+
+#define PGM "gcryptrnd"
+#define MYVERSION_LINE PGM " (Libgcrypt) " VERSION
+#define BUGREPORT_LINE "\nReport bugs to <bug-libgcrypt@gnupg.org>.\n"
+
+/* Pth wrapper function definitions. */
+GCRY_THREAD_OPTION_PTH_IMPL;
+
+
+/* Flag set to true if we have been daemonized. */
+static int running_detached;
+/* Flag indicating that a shutdown has been requested. */
+static int shutdown_pending;
+/* Counter for active connections. */
+static int active_connections;
+
+
+
+/* Local prototypes. */
+static void serve (int listen_fd);
+
+
+
+
+
+/* To avoid that a compiler optimizes certain memset calls away, these
+ macros may be used instead. */
+#define wipememory2(_ptr,_set,_len) do { \
+ volatile char *_vptr=(volatile char *)(_ptr); \
+ size_t _vlen=(_len); \
+ while(_vlen) { *_vptr=(_set); _vptr++; _vlen--; } \
+ } while(0)
+#define wipememory(_ptr,_len) wipememory2(_ptr,0,_len)
+
+
+
+
+/* Error printing utility. PRIORITY should be one of syslog's
+ priority levels. This functions prints to the stderr or syslog
+ depending on whether we are already daemonized. */
+static void
+logit (int priority, const char *format, ...)
+{
+ va_list arg_ptr;
+
+ va_start (arg_ptr, format) ;
+ if (running_detached)
+ {
+ vsyslog (priority, format, arg_ptr);
+ }
+ else
+ {
+ fputs (PGM ": ", stderr);
+ vfprintf (stderr, format, arg_ptr);
+ putc ('\n', stderr);
+ }
+ va_end (arg_ptr);
+}
+
+/* Callback used by libgcrypt for logging. */
+static void
+my_gcry_logger (void *dummy, int level, const char *format, va_list arg_ptr)
+{
+ (void)dummy;
+
+ /* Map the log levels. */
+ switch (level)
+ {
+ case GCRY_LOG_CONT: level = LOG_INFO /* FIXME */; break;
+ case GCRY_LOG_INFO: level = LOG_INFO; break;
+ case GCRY_LOG_WARN: level = LOG_WARNING; break;
+ case GCRY_LOG_ERROR:level = LOG_ERR; break;
+ case GCRY_LOG_FATAL:level = LOG_CRIT; break;
+ case GCRY_LOG_BUG: level = LOG_CRIT; break;
+ case GCRY_LOG_DEBUG:level = LOG_DEBUG; break;
+ default: level = LOG_ERR; break;
+ }
+ if (running_detached)
+ {
+ vsyslog (level, format, arg_ptr);
+ }
+ else
+ {
+ fputs (PGM ": ", stderr);
+ vfprintf (stderr, format, arg_ptr);
+ if (!*format || format[strlen (format)-1] != '\n')
+ putc ('\n', stderr);
+ }
+}
+
+
+/* The cleanup handler - used to wipe out the secure memory. */
+static void
+cleanup (void)
+{
+ gcry_control (GCRYCTL_TERM_SECMEM );
+}
+
+
+/* Make us a daemon and open the syslog. */
+static void
+daemonize (void)
+{
+ int i;
+ pid_t pid;
+
+ fflush (NULL);
+
+ pid = fork ();
+ if (pid == (pid_t)-1)
+ {
+ logit (LOG_CRIT, "fork failed: %s", strerror (errno));
+ exit (1);
+ }
+ if (pid)
+ exit (0);
+
+ if (setsid() == -1)
+ {
+ logit (LOG_CRIT, "setsid() failed: %s", strerror(errno));
+ exit (1);
+ }
+
+ signal (SIGHUP, SIG_IGN);
+
+ pid = fork ();
+ if (pid == (pid_t)-1)
+ {
+ logit (LOG_CRIT, PGM ": second fork failed: %s", strerror (errno));
+ exit (1);
+ }
+ if (pid)
+ exit (0); /* First child exits. */
+
+ running_detached = 1;
+
+ if (chdir("/"))
+ {
+ logit (LOG_CRIT, "chdir(\"/\") failed: %s", strerror (errno));
+ exit (1);
+ }
+ umask (0);
+
+ for (i=0; i <= 2; i++)
+ close (i);
+
+ openlog (PGM, LOG_PID, LOG_DAEMON);
+}
+
+
+static void
+disable_core_dumps (void)
+{
+#ifdef HAVE_SETRLIMIT
+ struct rlimit limit;
+
+ if (getrlimit (RLIMIT_CORE, &limit))
+ limit.rlim_max = 0;
+ limit.rlim_cur = 0;
+ if( !setrlimit (RLIMIT_CORE, &limit) )
+ return 0;
+ if (errno != EINVAL && errno != ENOSYS)
+ logit (LOG_ERR, "can't disable core dumps: %s\n", strerror (errno));
+#endif /* HAVE_SETRLIMIT */
+}
+
+
+
+static void
+print_version (int with_help)
+{
+ fputs (MYVERSION_LINE "\n"
+ "Copyright (C) 2006 Free Software Foundation, Inc.\n"
+ "License GPLv2+: GNU GPL version 2 or later "
+ "<http://www.gnu.org/licenses/old-licenses/gpl-2.0.html>\n"
+ "This is free software: you are free to change and redistribute it.\n"
+ "There is NO WARRANTY, to the extent permitted by law.\n",
+ stdout);
+
+ if (with_help)
+ fputs ("\n"
+ "Usage: " PGM " [OPTIONS] [SOCKETNAME]\n"
+ "Start Libgcrypt's random number daemon listening"
+ " on socket SOCKETNAME\n"
+ "SOCKETNAME defaults to XXX\n"
+ "\n"
+ " --no-detach do not deatach from the console\n"
+ " --version print version of the program and exit\n"
+ " --help display this help and exit\n"
+ BUGREPORT_LINE, stdout );
+
+ exit (0);
+}
+
+static int
+print_usage (void)
+{
+ fputs ("usage: " PGM " [OPTIONS] [SOCKETNAME]\n", stderr);
+ fputs (" (use --help to display options)\n", stderr);
+ exit (1);
+}
+
+
+int
+main (int argc, char **argv)
+{
+ int no_detach = 0;
+ gpg_error_t err;
+ struct sockaddr_un *srvr_addr;
+ socklen_t addrlen;
+ int fd;
+ int rc;
+ const char *socketname = "/var/run/libgcrypt/S.gcryptrnd";
+
+
+ if (argc)
+ {
+ argc--; argv++;
+ }
+ while (argc && **argv == '-' && (*argv)[1] == '-')
+ {
+ if (!(*argv)[2])
+ {
+ argc--; argv++;
+ break;
+ }
+ else if (!strcmp (*argv, "--version"))
+ print_version (0);
+ else if (!strcmp (*argv, "--help"))
+ print_version (1);
+ else if (!strcmp (*argv, "--no-detach"))
+ {
+ no_detach = 1;
+ argc--; argv++;
+ }
+ else
+ print_usage ();
+ }
+
+ if (argc == 1)
+ socketname = argv[0];
+ else if (argc > 1)
+ print_usage ();
+
+ if (!no_detach)
+ daemonize ();
+
+ signal (SIGPIPE, SIG_IGN);
+
+ logit (LOG_NOTICE, "started version " VERSION );
+
+ /* Libgcrypt requires us to register the threading model before we
+ do anything else with it. Note that this also calls pth_init. We
+ do the initialization while already running as a daemon to avoid
+ overhead with double initialization of Libgcrypt. */
+ err = gcry_control (GCRYCTL_SET_THREAD_CBS, &gcry_threads_pth);
+ if (err)
+ {
+ logit (LOG_CRIT, "can't register GNU Pth with Libgcrypt: %s",
+ gpg_strerror (err));
+ exit (1);
+ }
+
+ /* Check that the libgcrypt version is sufficient. */
+ if (!gcry_check_version (VERSION) )
+ {
+ logit (LOG_CRIT, "libgcrypt is too old (need %s, have %s)",
+ VERSION, gcry_check_version (NULL) );
+ exit (1);
+ }
+
+ /* Register the logging callback and tell Libcgrypt to put the
+ random pool into secure memory. */
+ gcry_set_log_handler (my_gcry_logger, NULL);
+ gcry_control (GCRYCTL_USE_SECURE_RNDPOOL);
+
+ /* Obviously we don't want to allow any core dumps. */
+ disable_core_dumps ();
+
+ /* Initialize the secure memory stuff which will also drop any extra
+ privileges we have. */
+ gcry_control (GCRYCTL_INIT_SECMEM, 16384, 0);
+
+ /* Register a cleanup handler. */
+ atexit (cleanup);
+
+ /* Create and listen on the socket. */
+ fd = socket (AF_UNIX, SOCK_STREAM, 0);
+ if (fd == -1)
+ {
+ logit (LOG_CRIT, "can't create socket: %s", strerror (errno));
+ exit (1);
+ }
+ srvr_addr = gcry_xmalloc (sizeof *srvr_addr);
+ memset (srvr_addr, 0, sizeof *srvr_addr);
+ srvr_addr->sun_family = AF_UNIX;
+ if (strlen (socketname) + 1 >= sizeof (srvr_addr->sun_path))
+ {
+ logit (LOG_CRIT, "socket name `%s' too long", socketname);
+ exit (1);
+ }
+ strcpy (srvr_addr->sun_path, socketname);
+ addrlen = (offsetof (struct sockaddr_un, sun_path)
+ + strlen (srvr_addr->sun_path) + 1);
+ rc = bind (fd, (struct sockaddr*) srvr_addr, addrlen);
+ if (rc == -1 && errno == EADDRINUSE)
+ {
+ remove (socketname);
+ rc = bind (fd, (struct sockaddr*) srvr_addr, addrlen);
+ }
+ if (rc == -1)
+ {
+ logit (LOG_CRIT, "error binding socket to `%s': %s",
+ srvr_addr->sun_path, strerror (errno));
+ close (fd);
+ exit (1);
+ }
+
+ if (listen (fd, 5 ) == -1)
+ {
+ logit (LOG_CRIT, "listen() failed: %s", strerror (errno));
+ close (fd);
+ exit (1);
+ }
+
+ logit (LOG_INFO, "listening on socket `%s', fd=%d",
+ srvr_addr->sun_path, fd);
+
+ serve (fd);
+ close (fd);
+
+ logit (LOG_NOTICE, "stopped version " VERSION );
+ return 0;
+}
+
+
+/* Send LENGTH bytes of BUFFER to file descriptor FD. Returns 0 on
+ success or another value on write error. */
+static int
+writen (int fd, const void *buffer, size_t length)
+{
+ while (length)
+ {
+ ssize_t n = pth_write (fd, buffer, length);
+ if (n < 0)
+ {
+ logit (LOG_ERR, "connection %d: write error: %s",
+ fd, strerror (errno));
+ return -1; /* write error */
+ }
+ length -= n;
+ buffer = (const char*)buffer + n;
+ }
+ return 0; /* Okay */
+}
+
+
+/* Send an error response back. Returns 0 on success. */
+static int
+send_error (int fd, int errcode)
+{
+ unsigned char buf[2];
+
+ buf[0] = errcode;
+ buf[1] = 0;
+ return writen (fd, buf, 2 );
+}
+
+/* Send a pong response back. Returns 0 on success or another value
+ on write error. */
+static int
+send_pong (int fd)
+{
+ return writen (fd, "\x00\x04pong", 6);
+}
+
+/* Send a nonce of size LENGTH back. Return 0 on success. */
+static int
+send_nonce (int fd, int length)
+{
+ unsigned char buf[2+255];
+ int rc;
+
+ assert (length >= 0 && length <= 255);
+ buf[0] = 0;
+ buf[1] = length;
+ gcry_create_nonce (buf+2, length);
+ rc = writen (fd, buf, 2+length );
+ wipememory (buf+2, length);
+ return rc;
+}
+
+/* Send a random of size LENGTH with quality LEVEL back. Return 0 on
+ success. */
+static int
+send_random (int fd, int length, int level)
+{
+ unsigned char buf[2+255];
+ int rc;
+
+ assert (length >= 0 && length <= 255);
+ assert (level == GCRY_STRONG_RANDOM || level == GCRY_VERY_STRONG_RANDOM);
+ buf[0] = 0;
+ buf[1] = length;
+ /* Note that we don't bother putting the random stuff into secure
+ memory because this daemon is anyway intended to be run under
+ root and it is questionable whether the kernel buffers etc. are
+ equally well protected. */
+ gcry_randomize (buf+2, length, level);
+ rc = writen (fd, buf, 2+length );
+ wipememory (buf+2, length);
+ return rc;
+}
+
+/* Main processing loop for a connection.
+
+ A request is made up of:
+
+ 1 byte Total length of request; must be 3
+ 1 byte Command
+ 0 = Ping
+ 10 = GetNonce
+ 11 = GetStrongRandom
+ 12 = GetVeryStrongRandom
+ (all other values are reserved)
+ 1 byte Number of requested bytes.
+ This is ignored for command Ping.
+
+ A response is made up of:
+
+ 1 byte Error Code
+ 0 = Everything is fine
+ 1 = Bad Command
+ 0xff = Other error.
+ (For a bad request the connection will simply be closed)
+ 1 byte Length of data
+ n byte data
+
+ The requests are read as long as the connection is open.
+
+
+ */
+static void
+connection_loop (int fd)
+{
+ unsigned char request[3];
+ unsigned char *p;
+ int nleft, n;
+ int rc;
+
+ for (;;)
+ {
+ for (nleft=3, p=request; nleft > 0; )
+ {
+ n = pth_read (fd, p, nleft);
+ if (!n && p == request)
+ return; /* Client terminated connection. */
+ if (n <= 0)
+ {
+ logit (LOG_ERR, "connection %d: read error: %s",
+ fd, n? strerror (errno) : "Unexpected EOF");
+ return;
+ }
+ p += n;
+ nleft -= n;
+ }
+ if (request[0] != 3)
+ {
+ logit (LOG_ERR, "connection %d: invalid length (%d) of request",
+ fd, request[0]);
+ return;
+ }
+
+ switch (request[1])
+ {
+ case 0: /* Ping */
+ rc = send_pong (fd);
+ break;
+ case 10: /* GetNonce */
+ rc = send_nonce (fd, request[2]);
+ break;
+ case 11: /* GetStrongRandom */
+ rc = send_random (fd, request[2], GCRY_STRONG_RANDOM);
+ break;
+ case 12: /* GetVeryStrongRandom */
+ rc = send_random (fd, request[2], GCRY_VERY_STRONG_RANDOM);
+ break;
+
+ default: /* Invalid command */
+ rc = send_error (fd, 1);
+ break;
+ }
+ if (rc)
+ break; /* A write error occurred while sending the response. */
+ }
+}
+
+
+
+/* Entry point for a connection's thread. */
+static void *
+connection_thread (void *arg)
+{
+ int fd = (int)arg;
+
+ active_connections++;
+ logit (LOG_INFO, "connection handler for fd %d started", fd);
+
+ connection_loop (fd);
+
+ close (fd);
+ logit (LOG_INFO, "connection handler for fd %d terminated", fd);
+ active_connections--;
+
+ return NULL;
+}
+
+
+/* This signal handler is called from the main loop between acepting
+ connections. It is called on the regular stack, thus no special
+ caution needs to be taken. It returns true to indicate that the
+ process should terminate. */
+static int
+handle_signal (int signo)
+{
+ switch (signo)
+ {
+ case SIGHUP:
+ logit (LOG_NOTICE, "SIGHUP received - re-reading configuration");
+ break;
+
+ case SIGUSR1:
+ logit (LOG_NOTICE, "SIGUSR1 received - no action defined");
+ break;
+
+ case SIGUSR2:
+ logit (LOG_NOTICE, "SIGUSR2 received - no action defined");
+ break;
+
+ case SIGTERM:
+ if (!shutdown_pending)
+ logit (LOG_NOTICE, "SIGTERM received - shutting down ...");
+ else
+ logit (LOG_NOTICE, "SIGTERM received - still %d active connections",
+ active_connections);
+ shutdown_pending++;
+ if (shutdown_pending > 2)
+ {
+ logit (LOG_NOTICE, "shutdown forced");
+ return 1;
+ }
+ break;
+
+ case SIGINT:
+ logit (LOG_NOTICE, "SIGINT received - immediate shutdown");
+ return 1;
+
+ default:
+ logit (LOG_NOTICE, "signal %d received - no action defined\n", signo);
+ }
+ return 0;
+}
+
+
+
+/* Main server loop. This is called with the FD of the listening
+ socket. */
+static void
+serve (int listen_fd)
+{
+ pth_attr_t tattr;
+ pth_event_t ev;
+ sigset_t sigs;
+ int signo;
+ struct sockaddr_un paddr;
+ socklen_t plen = sizeof (paddr);
+ int fd;
+
+ tattr = pth_attr_new();
+ pth_attr_set (tattr, PTH_ATTR_JOINABLE, 0);
+ pth_attr_set (tattr, PTH_ATTR_STACK_SIZE, 256*1024);
+ pth_attr_set (tattr, PTH_ATTR_NAME, "connection");
+
+ sigemptyset (&sigs);
+ sigaddset (&sigs, SIGHUP);
+ sigaddset (&sigs, SIGUSR1);
+ sigaddset (&sigs, SIGUSR2);
+ sigaddset (&sigs, SIGINT);
+ sigaddset (&sigs, SIGTERM);
+ ev = pth_event (PTH_EVENT_SIGS, &sigs, &signo);
+
+ for (;;)
+ {
+ if (shutdown_pending)
+ {
+ if (!active_connections)
+ break; /* Ready. */
+
+ /* Do not accept anymore connections but wait for existing
+ connections to terminate. */
+ signo = 0;
+ pth_wait (ev);
+ if (pth_event_occurred (ev) && signo)
+ if (handle_signal (signo))
+ break; /* Stop the loop. */
+ continue;
+ }
+
+ gcry_fast_random_poll ();
+ fd = pth_accept_ev (listen_fd, (struct sockaddr *)&paddr, &plen, ev);
+ if (fd == -1)
+ {
+ if (pth_event_occurred (ev))
+ {
+ if (handle_signal (signo))
+ break; /* Stop the loop. */
+ continue;
+ }
+ logit (LOG_WARNING, "accept failed: %s - waiting 1s\n",
+ strerror (errno));
+ gcry_fast_random_poll ();
+ pth_sleep (1);
+ continue;
+ }
+
+ if (!pth_spawn (tattr, connection_thread, (void*)fd))
+ {
+ logit (LOG_ERR, "error spawning connection handler: %s\n",
+ strerror (errno) );
+ close (fd);
+ }
+ }
+
+ pth_event_free (ev, PTH_FREE_ALL);
+}