Copy the KDE 3.5 branch to branches/trinity for new KDE 3.5 features.

BUG:215923


git-svn-id: svn://anonsvn.kde.org/home/kde/branches/trinity/kdebase@1054174 283d02a7-25f6-0310-bc7c-ecb5cbfe19da

1 files changed, 448 insertions, 0 deletions

diff --git a/kcheckpass/kcheckpass.c b/kcheckpass/kcheckpass.c
new file mode 100644
index 000000000..6a0550969
--- /dev/null
+++ b/kcheckpass/kcheckpass.c
@@ -0,0 +1,448 @@
+/*****************************************************************
+ *
+ *	kcheckpass - Simple password checker
+ *
+ * This program 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.
+ *
+ * This program 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.
+ *
+ *
+ *	kcheckpass is a simple password checker. Just invoke and
+ *      send it the password on stdin.
+ *
+ *	If the password was accepted, the program exits with 0;
+ *	if it was rejected, it exits with 1. Any other exit
+ *	code signals an error.
+ *
+ *	It's hopefully simple enough to allow it to be setuid
+ *	root.
+ *
+ *	Compile with -DHAVE_VSYSLOG if you have vsyslog().
+ *	Compile with -DHAVE_PAM if you have a PAM system,
+ *	and link with -lpam -ldl.
+ *	Compile with -DHAVE_SHADOW if you have a shadow
+ *	password system.
+ *
+ *	Copyright (C) 1998, Caldera, Inc.
+ *	Released under the GNU General Public License
+ *
+ *	Olaf Kirch <okir@caldera.de>         General Framework and PAM support
+ *	Christian Esken <esken@kde.org>      Shadow and /etc/passwd support
+ *	Roberto Teixeira <maragato@kde.org>  other user (-U) support
+ *	Oswald Buddenhagen <ossi@kde.org>    Binary server mode
+ *
+ *      Other parts were taken from kscreensaver's passwd.cpp.
+ *
+ *****************************************************************/
+
+#include "kcheckpass.h"
+
+#include <stdarg.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <syslog.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <time.h>
+
+/* Compatibility: accept some options from environment variables */
+#define ACCEPT_ENV
+
+#define THROTTLE 3
+
+static int havetty, sfd = -1, nullpass;
+
+static char *
+conv_legacy (ConvRequest what, const char *prompt)
+{
+    char		*p, *p2;
+    int			len;
+    char		buf[1024];
+
+    switch (what) {
+    case ConvGetBinary:
+	break;
+    case ConvGetNormal:
+	/* there is no prompt == 0 case */
+	if (!havetty)
+	    break;
+	/* i guess we should use /dev/tty ... */
+	fputs(prompt, stdout);
+	fflush(stdout);
+	if (!fgets(buf, sizeof(buf), stdin))
+	    return 0;
+	len = strlen(buf);
+	if (len && buf[len - 1] == '\n')
+	    buf[--len] = 0;
+	return strdup(buf);
+    case ConvGetHidden:
+	if (havetty) {
+#ifdef HAVE_GETPASSPHRASE
+	    p = getpassphrase(prompt ? prompt : "Password: ");
+#else
+	    p = getpass(prompt ? prompt : "Password: ");
+#endif
+	    p2 = strdup(p);
+	    memset(p, 0, strlen(p));
+	    return p2;
+	} else {
+	    if (prompt)
+		break;
+	    if ((len = read(0, buf, sizeof(buf) - 1)) < 0) {
+		message("Cannot read password\n");
+		return 0;
+	    } else {
+		if (len && buf[len - 1] == '\n')
+		    --len;
+		buf[len] = 0;
+		p2 = strdup(buf);
+		memset(buf, 0, len);
+		return p2;
+	    }
+	}
+    case ConvPutInfo:
+	message("Information: %s\n", prompt);
+	return 0;
+    case ConvPutError:
+	message("Error: %s\n", prompt);
+	return 0;
+    }
+    message("Authentication backend requested data type which cannot be handled.\n");
+    return 0;
+}
+
+
+static int
+Reader (void *buf, int count)
+{
+    int ret, rlen;
+
+    for (rlen = 0; rlen < count; ) {
+      dord:
+	ret = read (sfd, (void *)((char *)buf + rlen), count - rlen);
+	if (ret < 0) {
+	    if (errno == EINTR)
+		goto dord;
+	    if (errno == EAGAIN)
+		break;
+	    return -1;
+	}
+	if (!ret)
+	    break;
+	rlen += ret;
+    }
+    return rlen;
+}
+
+static void
+GRead (void *buf, int count)
+{
+    if (Reader (buf, count) != count) {
+	message ("Communication breakdown on read\n");
+	exit(15);
+    }
+}
+
+static void
+GWrite (const void *buf, int count)
+{
+    if (write (sfd, buf, count) != count) {
+	message ("Communication breakdown on write\n");
+	exit(15);
+    }
+}
+
+static void
+GSendInt (int val)
+{
+    GWrite (&val, sizeof(val));
+}
+
+static void
+GSendStr (const char *buf)
+{
+    unsigned len = buf ? strlen (buf) + 1 : 0;
+    GWrite (&len, sizeof(len));
+    GWrite (buf, len);
+}
+
+static void
+GSendArr (int len, const char *buf)
+{
+    GWrite (&len, sizeof(len));
+    GWrite (buf, len);
+}
+
+static int
+GRecvInt (void)
+{
+    int val;
+
+    GRead (&val, sizeof(val));
+    return val;
+}
+
+static char *
+GRecvStr (void)
+{
+    unsigned len;
+    char *buf;
+
+    if (!(len = GRecvInt()))
+	return (char *)0;
+    if (len > 0x1000 || !(buf = malloc (len))) {
+	message ("No memory for read buffer\n");
+	exit(15);
+    }
+    GRead (buf, len);
+    buf[len - 1] = 0; /* we're setuid ... don't trust "them" */
+    return buf;
+}
+
+static char *
+GRecvArr (void)
+{
+    unsigned len;
+    char *arr;
+
+    if (!(len = (unsigned) GRecvInt()))
+	return (char *)0;
+    if (len > 0x10000 || !(arr = malloc (len))) {
+	message ("No memory for read buffer\n");
+	exit(15);
+    }
+    GRead (arr, len);
+    return arr;
+}
+
+
+static char *
+conv_server (ConvRequest what, const char *prompt)
+{
+    GSendInt (what);
+    switch (what) {
+    case ConvGetBinary:
+      {
+	unsigned const char *up = (unsigned const char *)prompt;
+	int len = up[3] | (up[2] << 8) | (up[1] << 16) | (up[0] << 24);
+	GSendArr (len, prompt);
+	return GRecvArr ();
+      }
+    case ConvGetNormal:
+    case ConvGetHidden:
+      {
+	char *msg;
+	GSendStr (prompt);
+	msg = GRecvStr ();
+	if (msg && (GRecvInt() & IsPassword) && !*msg)
+	  nullpass = 1;
+	return msg;
+      }
+    case ConvPutInfo:
+    case ConvPutError:
+    default:
+	GSendStr (prompt);
+	return 0;
+    }
+}
+
+void
+message(const char *fmt, ...)
+{
+  va_list		ap;
+
+  va_start(ap, fmt);
+  vfprintf(stderr, fmt, ap);
+  va_end(ap);
+}
+
+#ifndef O_NOFOLLOW
+# define O_NOFOLLOW 0
+#endif
+
+static void ATTR_NORETURN
+usage(int exitval)
+{
+  message(
+	  "usage: kcheckpass {-h|[-c caller] [-m method] [-U username|-S handle]}\n"
+	  "  options:\n"
+	  "    -h           this help message\n"
+	  "    -U username  authenticate the specified user instead of current user\n"
+	  "    -S handle    operate in binary server mode on file descriptor handle\n"
+	  "    -c caller    the calling application, effectively the PAM service basename\n"
+	  "    -m method    use the specified authentication method (default: \"classic\")\n"
+	  "  exit codes:\n"
+	  "    0 success\n"
+	  "    1 invalid password\n"
+	  "    2 cannot read password database\n"
+	  "    Anything else tells you something's badly hosed.\n"
+	);
+  exit(exitval);
+}
+
+int
+main(int argc, char **argv)
+{
+#ifdef HAVE_PAM
+  const char	*caller = KCHECKPASS_PAM_SERVICE;
+#endif
+  const char	*method = "classic";
+  const char	*username = 0;
+#ifdef ACCEPT_ENV
+  char		*p;
+#endif
+  struct passwd	*pw;
+  int		c, nfd, lfd;
+  uid_t		uid;
+  time_t	nexttime;
+  AuthReturn	ret;
+  struct flock lk;
+  char fname[64], fcont[64];
+
+#ifdef HAVE_OSF_C2_PASSWD
+  initialize_osf_security(argc, argv);
+#endif
+
+  /* Make sure stdout/stderr are open */
+  for (c = 1; c <= 2; c++) {
+    if (fcntl(c, F_GETFL) == -1) {
+      if ((nfd = open("/dev/null", O_WRONLY)) < 0) {
+        message("cannot open /dev/null: %s\n", strerror(errno));
+        exit(10);
+      }
+      if (c != nfd) {
+        dup2(nfd, c);
+        close(nfd);
+      }
+    }
+  }
+
+  havetty = isatty(0);
+
+  while ((c = getopt(argc, argv, "hc:m:U:S:")) != -1) {
+    switch (c) {
+    case 'h':
+      usage(0);
+      break;
+    case 'c':
+#ifdef HAVE_PAM
+      caller = optarg;
+#endif
+      break;
+    case 'm':
+      method = optarg;
+      break;
+    case 'U':
+      username = optarg;
+      break;
+    case 'S':
+      sfd = atoi(optarg);
+      break;
+    default:
+      message("Command line option parsing error\n");
+      usage(10);
+    }
+  }
+
+#ifdef ACCEPT_ENV
+# ifdef HAVE_PAM
+  if ((p = getenv("KDE_PAM_ACTION")))
+    caller = p;
+# endif
+  if ((p = getenv("KCHECKPASS_USER")))
+    username = p;
+#endif  
+
+  uid = getuid();
+  if (!username) {
+    if (!(p = getenv("LOGNAME")) || !(pw = getpwnam(p)) || pw->pw_uid != uid)
+      if (!(p = getenv("USER")) || !(pw = getpwnam(p)) || pw->pw_uid != uid)
+        if (!(pw = getpwuid(uid))) {
+          message("Cannot determinate current user\n");
+          return AuthError;
+        }
+    if (!(username = strdup(pw->pw_name))) {
+      message("Out of memory\n");
+      return AuthError;
+    }
+  }
+
+  /*
+   * Throttle kcheckpass invocations to avoid abusing it for bruteforcing
+   * the password. This delay belongs to the *previous* invocation, where
+   * we can't enforce it reliably (without risking giving away the result
+   * before it is due). We don't differentiate between success and failure -
+   * it's not expected to have a noticable adverse effect.
+   */
+  if ( uid != geteuid() ) {
+    sprintf(fname, "/var/run/kcheckpass.%d", uid);
+    if ((lfd = open(fname, O_RDWR | O_CREAT | O_NOFOLLOW, 0600)) < 0) {
+      message("Cannot open lockfile\n");
+      return AuthError;
+    }
+
+    lk.l_type = F_WRLCK;
+    lk.l_whence = SEEK_SET;
+    lk.l_start = lk.l_len = 0;
+    if (fcntl(lfd, F_SETLKW, &lk)) {
+      message("Cannot obtain lock\n");
+      return AuthError;
+    }
+
+    if ((c = read(lfd, fcont, sizeof(fcont)-1)) > 0 &&
+        (fcont[c] = '\0', sscanf(fcont, "%ld", &nexttime) == 1))
+    {
+      time_t ct = time(0);
+      if (nexttime > ct && nexttime < ct + THROTTLE)
+        sleep(nexttime - ct);
+    }
+
+    lseek(lfd, 0, SEEK_SET);
+    write(lfd, fcont, sprintf(fcont, "%lu\n", time(0) + THROTTLE));
+
+    close(lfd);
+  }
+
+  /* Now do the fandango */
+  ret = Authenticate(
+#ifdef HAVE_PAM
+                     caller,
+#endif
+                     method,
+                     username, 
+                     sfd < 0 ? conv_legacy : conv_server);
+
+    if (ret == AuthBad) {
+      message("Authentication failure\n");
+      if (!nullpass) {
+        openlog("kcheckpass", LOG_PID, LOG_AUTH);
+        syslog(LOG_NOTICE, "Authentication failure for %s (invoked by uid %d)", username, uid);
+      }
+    }
+
+  return ret;
+}
+
+void
+dispose(char *str)
+{
+    memset(str, 0, strlen(str));
+    free(str);
+}
+
+/*****************************************************************
+  The real authentication methods are in separate source files.
+  Look in checkpass_*.c
+*****************************************************************/