- {
- unsigned char buf[BUFSIZE];
- int i,ret=0,err=0;
- FILE *out = NULL;
- int n;
-
-#ifdef VMS
- /* Under VMS, fopen(file, "wb") will create a new version of the
- same file. This is not good, so let's try updating an existing
- one, and create file only if it doesn't already exist. */
- /* At the same time, if we just update a file, we also need to
- truncate it, and unfortunately, ftruncate() and truncate() do
- not exist everywhere. All that remains is to delete old versions
- of the random data file (done at the end). */
-#if 0
- out=fopen(file,"rb+");
- if (out == NULL && errno != ENOENT)
- goto err;
-#endif
-#endif
-
- if (out == NULL)
- {
-#if defined O_CREAT && defined O_EXCL
- /* chmod(..., 0600) is too late to protect the file,
- * permissions should be restrictive from the start */
- int fd = open(file, O_CREAT | O_EXCL, 0600);
- if (fd != -1)
- out = fdopen(fd, "wb");
- else /* the open(...) reportedly fails on Win98 w/ VisualC */
- out = fopen(file,"wb");
+{
+ unsigned char buf[BUFSIZE];
+ int i, ret = 0, rand_err = 0;
+ FILE *out = NULL;
+ int n;
+#ifndef OPENSSL_NO_POSIX_IO
+ struct stat sb;
+
+ i = stat(file, &sb);
+ if (i != -1) {
+# if defined(S_ISBLK) && defined(S_ISCHR)
+ if (S_ISBLK(sb.st_mode) || S_ISCHR(sb.st_mode)) {
+ /*
+ * 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_NO_POSIX_IO) && !defined(OPENSSL_SYS_VMS)
+ {
+# ifndef O_BINARY
+# define O_BINARY 0
+# endif
+ /*
+ * chmod(..., 0600) is too late to protect the file, permissions
+ * should be restrictive from the start
+ */
+ int fd = open(file, O_WRONLY | O_CREAT | O_BINARY, 0600);
+ if (fd != -1)
+ out = fdopen(fd, "wb");
+ }
+#endif
+
+#ifdef OPENSSL_SYS_VMS
+ /*
+ * VMS NOTE: Prior versions of this routine created a _new_ version of
+ * the rand file for each call into this routine, then deleted all
+ * existing versions named ;-1, and finally renamed the current version
+ * as ';1'. Under concurrent usage, this resulted in an RMS race
+ * condition in rename() which could orphan files (see vms message help
+ * for RMS$_REENT). With the fopen() calls below, openssl/VMS now shares
+ * the top-level version of the rand file. Note that there may still be
+ * conditions where the top-level rand file is locked. If so, this code
+ * will then create a new version of the rand file. Without the delete
+ * and rename code, this can result in ascending file versions that stop
+ * at version 32767, and this routine will then return an error. The
+ * remedy for this is to recode the calling application to avoid
+ * concurrent use of the rand file, or synchronize usage at the
+ * application level. Also consider whether or not you NEED a persistent
+ * rand file in a concurrent use situation.
+ */
+
+ out = vms_fopen(file, "rb+", VMS_OPEN_ATTRS);
+ if (out == NULL)
+ out = vms_fopen(file, "wb", VMS_OPEN_ATTRS);