X-Git-Url: https://git.openssl.org/gitweb/?a=blobdiff_plain;f=crypto%2Frand%2Frandfile.c;h=7533ea57882dd7bf92891501adea50ce517a620c;hb=4700aea951dcba9b1e3b724bf4d8f0c712578892;hp=7c2673a61ffd31fabd4d05245976697834cdfa4a;hpb=54a656ef081f72a740c550ebd8099b40b8b5cde0;p=openssl.git

diff --git a/crypto/rand/randfile.c b/crypto/rand/randfile.c
index 7c2673a61f..7533ea5788 100644
--- a/crypto/rand/randfile.c
+++ b/crypto/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 500
+
 #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>
@@ -71,9 +75,7 @@
 #ifndef NO_SYS_TYPES_H
 # include <sys/types.h>
 #endif
-#ifdef MAC_OS_pre_X
-# include <stat.h>
-#else
+#ifndef OPENSSL_NO_POSIX_IO
 # include <sys/stat.h>
 #endif
 
@@ -92,20 +94,34 @@ int RAND_load_file(const char *file, long bytes)
 	 * if bytes == -1, read complete file. */
 
 	MS_STATIC unsigned char buf[BUFSIZE];
+#ifndef OPENSSL_NO_POSIX_IO
 	struct stat sb;
+#endif
 	int i,ret=0,n;
 	FILE *in;
 
 	if (file == NULL) return(0);
 
+#ifndef OPENSSL_NO_POSIX_IO
 	i=stat(file,&sb);
 	/* If the state fails, put some crap in anyway */
-	RAND_add(&sb,sizeof(sb),0);
+	RAND_add(&sb,sizeof(sb),0.0);
 	if (i < 0) return(0);
+#endif
 	if (bytes == 0) return(ret);
 
 	in=fopen(file,"rb");
 	if (in == NULL) goto err;
+#if defined(S_IFBLK) && defined(S_IFCHR) && !defined(OPNESSL_NO_POSIX_IO)
+	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)
@@ -115,7 +131,7 @@ int RAND_load_file(const char *file, long bytes)
 		i=fread(buf,1,n,in);
 		if (i <= 0) break;
 		/* even if n != i, use the full array */
-		RAND_add(buf,n,i);
+		RAND_add(buf,n,(double)i);
 		ret+=i;
 		if (bytes > 0)
 			{
@@ -124,7 +140,7 @@ int RAND_load_file(const char *file, long bytes)
 			}
 		}
 	fclose(in);
-	memset(buf,0,BUFSIZE);
+	OPENSSL_cleanse(buf,BUFSIZE);
 err:
 	return(ret);
 	}
@@ -135,8 +151,26 @@ int RAND_write_file(const char *file)
 	int i,ret=0,rand_err=0;
 	FILE *out = NULL;
 	int n;
+#ifndef OPENSSL_NO_POSIX_IO
+	struct stat sb;
 	
-#if defined(O_CREAT) && !defined(OPENSSL_SYS_WIN32)
+	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
+	}
+#endif
+
+#if defined(O_CREAT) && !defined(OPENSSL_SYS_WIN32) && !defined(OPENSSL_NO_POSIX_IO)
+	{
 	/* For some reason Win32 can't write to files created this way */
 	
 	/* chmod(..., 0600) is too late to protect the file,
@@ -144,6 +178,7 @@ int RAND_write_file(const char *file)
 	int fd = open(file, O_CREAT, 0600);
 	if (fd != -1)
 		out = fdopen(fd, "wb");
+	}
 #endif
 	if (out == NULL)
 		out = fopen(file,"wb");
@@ -189,7 +224,7 @@ int RAND_write_file(const char *file)
 #endif /* OPENSSL_SYS_VMS */
 
 	fclose(out);
-	memset(buf,0,BUFSIZE);
+	OPENSSL_cleanse(buf,BUFSIZE);
 err:
 	return (rand_err ? -1 : ret);
 	}
@@ -197,16 +232,17 @@ 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 +254,36 @@ 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);
 	}