1 files changed, 60 insertions, 11 deletions

diff --git a/src/lib/libcrypto/rand/randfile.c b/src/lib/libcrypto/rand/randfile.c
index 41574768ab..f5d0843d13 100644
--- a/src/lib/libcrypto/rand/randfile.c
+++ b/src/lib/libcrypto/rand/randfile.c
@@ -56,6 +56,9 @@
  * [including the GNU Public Licence.]
  */
 
+/* We need to define this to get macros like S_IFBLK and S_IFCHR */
+#define _XOPEN_SOURCE 1
+
 #include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -64,6 +67,7 @@
 #include "e_os.h"
 #include <openssl/crypto.h>
 #include <openssl/rand.h>
+#include <openssl/buffer.h>
 
 #ifdef OPENSSL_SYS_VMS
 #include <unixio.h>
@@ -106,6 +110,16 @@ int RAND_load_file(const char *file, long bytes)
 
         in=fopen(file,"rb");
         if (in == NULL) goto err;
+#if defined(S_IFBLK) && defined(S_IFCHR)
+        if (sb.st_mode & (S_IFBLK | S_IFCHR)) {
+          /* this file is a device. we don't want read an infinite number
+           * of bytes from a random device, nor do we want to use buffered
+           * I/O because we will waste system entropy. 
+           */
+          bytes = (bytes == -1) ? 2048 : bytes; /* ok, is 2048 enough? */
+          setvbuf(in, NULL, _IONBF, 0); /* don't do buffered reads */
+        }
+#endif
         for (;;)
                 {
                 if (bytes > 0)
@@ -135,7 +149,22 @@ int RAND_write_file(const char *file)
         int i,ret=0,rand_err=0;
         FILE *out = NULL;
         int n;
+        struct stat sb;
         
+        i=stat(file,&sb);
+        if (i != -1) { 
+#if defined(S_IFBLK) && defined(S_IFCHR)
+          if (sb.st_mode & (S_IFBLK | S_IFCHR)) {
+            /* this file is a device. we don't write back to it. 
+             * we "succeed" on the assumption this is some sort 
+             * of random device. Otherwise attempting to write to 
+             * and chmod the device causes problems.
+             */
+            return(1); 
+          }
+#endif
+        }
+
 #if defined(O_CREAT) && !defined(OPENSSL_SYS_WIN32)
         /* For some reason Win32 can't write to files created this way */
         
@@ -197,16 +226,17 @@ err:
 const char *RAND_file_name(char *buf, size_t size)
         {
         char *s=NULL;
-        char *ret=NULL;
+        int ok = 0;
+#ifdef __OpenBSD__
+        struct stat sb;
+#endif
 
         if (OPENSSL_issetugid() == 0)
                 s=getenv("RANDFILE");
-        if (s != NULL)
+        if (s != NULL && *s && strlen(s) + 1 < size)
                 {
-                if(strlen(s) >= size)
+                if (BUF_strlcpy(buf,s,size) >= size)
                         return NULL;
-                strcpy(buf,s);
-                ret=buf;
                 }
         else
                 {
@@ -218,17 +248,36 @@ const char *RAND_file_name(char *buf, size_t size)
                         s = DEFAULT_HOME;
                         }
 #endif
-                if (s != NULL && (strlen(s)+strlen(RFILE)+2 < size))
+                if (s && *s && strlen(s)+strlen(RFILE)+2 < size)
                         {
-                        strcpy(buf,s);
+                        BUF_strlcpy(buf,s,size);
 #ifndef OPENSSL_SYS_VMS
-                        strcat(buf,"/");
+                        BUF_strlcat(buf,"/",size);
 #endif
-                        strcat(buf,RFILE);
-                        ret=buf;
+                        BUF_strlcat(buf,RFILE,size);
+                        ok = 1;
                         }
                 else
                         buf[0] = '\0'; /* no file name */
                 }
-        return(ret);
+
+#ifdef __OpenBSD__
+        /* given that all random loads just fail if the file can't be 
+         * seen on a stat, we stat the file we're returning, if it
+         * fails, use /dev/arandom instead. this allows the user to 
+         * use their own source for good random data, but defaults
+         * to something hopefully decent if that isn't available. 
+         */
+
+        if (!ok)
+                if (BUF_strlcpy(buf,"/dev/arandom",size) >= size) {
+                        return(NULL);
+                }       
+        if (stat(buf,&sb) == -1)
+                if (BUF_strlcpy(buf,"/dev/arandom",size) >= size) {
+                        return(NULL);
+                }       
+
+#endif
+        return(buf);
         }