Merge branch 'pr-187'

configure.ac

@@ -159,6 +159,20 @@ if test "$gl_gcc_warnings" = yes; then
   gl_WARN_ADD([-fdiagnostics-show-option])
 fi
 
+# Enable more secure memset if available
+AC_CHECK_FUNCS([memset_s explicit_bzero explicit_memset])
+AC_MSG_CHECKING(whether we can use inline asm code)
+AC_LINK_IFELSE([AC_LANG_PROGRAM([[]],
+  [[
+    int a = 42;
+    int *pnt = &a;
+    __asm__ __volatile__ ("" : : "r"(pnt) : "memory");
+  ]])],
+  [AC_MSG_RESULT(yes)
+     AC_DEFINE([HAVE_INLINE_ASM], [1], [inline asm code can be used])]
+  [AC_MSG_RESULT(no)]
+)
+
 AC_CONFIG_FILES(Makefile)
 AC_CONFIG_FILES(tests/Makefile)
 AC_OUTPUT

pam_yubico.c

@@ -1,5 +1,5 @@
 /* Written by Simon Josefsson <simon@yubico.com>.
- * Copyright (c) 2006-2016 Yubico AB
+ * Copyright (c) 2006-2019 Yubico AB
  * Copyright (c) 2011 Tollef Fog Heen <tfheen@err.no>
  * All rights reserved.
  *
@@ -45,6 +45,7 @@
 
 #include "util.h"
 #include "drop_privs.h"
+#include "ykbzero.h"
 
 #include <ykclient.h>
 
@@ -998,7 +999,7 @@ pam_sm_authenticate (pam_handle_t * pamh,
 	      pam_strerror (pamh, retval));
 	  goto done;
 	}
-      DBG ("get password returned: %s", password);
+      DBG ("get password returned: /* not logged */");
     }
 
   if (cfg->use_first_pass && password == NULL)
@@ -1263,7 +1264,12 @@ pam_sm_authenticate (pam_handle_t * pamh,
 
 done:
   if (onlypasswd)
+    {
+      insecure_memzero(onlypasswd, strlen(onlypasswd));
       free(onlypasswd);
+    }
+  insecure_memzero(otp, sizeof(otp));
+  insecure_memzero(otp_id, sizeof(otp_id));
   if (templates > 0)
     {
       size_t i;

ykbzero.h

@@ -0,0 +1,62 @@
+/* -*- mode:C; c-file-style: "bsd" -*- */
+/*
+ * Copyright (c) 2008-2019 Yubico AB
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *
+ *     * Redistributions in binary form must reproduce the above
+ *       copyright notice, this list of conditions and the following
+ *       disclaimer in the documentation and/or other materials provided
+ *       with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef	__YKBZERO_H_INCLUDED__
+#define	__YKBZERO_H_INCLUDED__
+
+#ifdef _WIN32
+#include <windows.h>
+#else
+#include <string.h>
+#endif
+
+#ifdef _WIN32
+#define insecure_memzero(buf, len) SecureZeroMemory(buf, len)
+#elif HAVE_MEMSET_S
+#define insecure_memzero(buf, len) memset_s(buf, len, 0, len)
+#elif HAVE_EXPLICIT_BZERO
+#define insecure_memzero(buf, len) explicit_bzero(buf, len)
+#elif HAVE_EXPLICIT_MEMSET
+#define insecure_memzero(buf, len) explicit_memset(buf, 0, len)
+#elif HAVE_INLINE_ASM
+#define insecure_memzero(buf, len) do {                                 \
+                memset(buf, 0, len);                                    \
+                __asm__ __volatile__ ("" : : "r"(buf) : "memory");      \
+        } while (0)
+#else
+#define insecure_memzero(buf, len) do {                                 \
+                volatile unsigned char *volatile __buf_ =               \
+                        (volatile unsigned char *volatile)buf;          \
+                size_t __i_ = 0;                                        \
+                while (__i_ < len) __buf_[__i_++] = 0;                  \
+        } while (0)
+#endif
+
+#endif	/* __YKBZERO_H_INCLUDED__ */