1 files changed, 36 insertions, 0 deletions

diff --git a/ffd/util.c b/ffd/util.c
index c8bb90b..5c3d6e6 100644
--- a/ffd/util.c
+++ b/ffd/util.c
@@ -24,9 +24,16 @@
 */
 
 
+#define _GNU_SOURCE
+
 #include "util.h"
 
+#include <errno.h>
+#include <fcntl.h>
 #include <stdio.h>
+#include <unistd.h>
+
+#include <sys/stat.h>
 
 
 bool file_readv(const char *file, const char *format, va_list ap) {
@@ -40,3 +47,32 @@ bool file_readv(const char *file, const char *format, va_list ap) {
 
 	return (ret > 0);
 }
+
+
+
+void random_bytes(void *buffer, size_t len) {
+	size_t read_bytes = 0;
+
+	int fd = open("/dev/urandom", O_RDONLY);
+
+	if (fd < 0) {
+		fprintf(stderr, "unable to open random device: %m\n");
+		exit(1);
+	}
+
+	while (read_bytes < len) {
+		ssize_t ret = read(fd, ((char*)buffer)+read_bytes, len-read_bytes);
+
+		if (ret < 0) {
+			if (errno == EINTR)
+				continue;
+
+			fprintf(stderr, "unable to read from random device: %m\n");
+			exit(1);
+		}
+
+		read_bytes += ret;
+	}
+
+	close(fd);
+}