Initial checking of what was revision 56 on http://luks.endorphin.org/svn/cryptsetup

git-svn-id: https://cryptsetup.googlecode.com/svn/trunk@3 36d66b0a-2a48-0410-832c-cd162a569da5

luks/random.c

@@ -0,0 +1,48 @@
+/*
+ *	Random supply helper
+ * Copyright 2004, Clemens Fruhwirth <clemens@endorphin.org>
+ *
+ */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <stdio.h>
+#include <unistd.h>
+
+static int randomfd = -1; 
+
+int openRandom() {
+    if(randomfd == -1) 
+	randomfd = open("/dev/urandom", O_RDONLY);
+    return randomfd;
+}
+
+/* This method leaks a file descriptor that can be obtained by calling
+   closeRandom */
+int getRandom(char *buf, size_t len)
+{
+    int r = 0;
+
+    if(openRandom() == -1) {
+	perror("getRandom:");
+	return -EINVAL;
+    }
+    while(len) {
+	int r;
+	r = read(randomfd,buf,len);
+	if (-1 == r && errno != -EINTR) {	
+	    perror("read: "); return -EINVAL;
+	}
+	len-= r; buf += r;
+    }
+    return r;
+}
+
+void closeRandom() {
+    if(randomfd != -1) {
+	close(randomfd);
+	randomfd = -1;
+    }
+}