Add qemu 2.4.0

[kvmfornfv.git] / qemu / roms / ipxe / src / interface / linux / linux_entropy.c

diff --git a/qemu/roms/ipxe/src/interface/linux/linux_entropy.c b/qemu/roms/ipxe/src/interface/linux/linux_entropy.c
new file mode 100644 (file)
index 0000000..4671a48
--- /dev/null
+++ b/qemu/roms/ipxe/src/interface/linux/linux_entropy.c
@@ -0,0 +1,97 @@
+/*
+ * Copyright (C) 2012 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+/** @file
+ *
+ * Linux entropy source
+ *
+ */
+
+#include <stdint.h>
+#include <errno.h>
+#include <linux_api.h>
+#include <ipxe/entropy.h>
+
+/** Entropy source filename */
+static const char entropy_filename[] = "/dev/random";
+
+/** Entropy source file handle */
+static int entropy_fd;
+
+/**
+ * Enable entropy gathering
+ *
+ * @ret rc             Return status code
+ */
+static int linux_entropy_enable ( void ) {
+
+       /* Open entropy source */
+       entropy_fd = linux_open ( entropy_filename, O_RDONLY );
+       if ( entropy_fd < 0 ) {
+               DBGC ( &entropy_fd, "ENTROPY could not open %s: %s\n",
+                      entropy_filename, linux_strerror ( linux_errno ) );
+               return entropy_fd;
+       }
+
+       return 0;
+}
+
+/**
+ * Disable entropy gathering
+ *
+ */
+static void linux_entropy_disable ( void ) {
+
+       /* Close entropy source */
+       linux_close ( entropy_fd );
+}
+
+/**
+ * Get noise sample
+ *
+ * @ret noise          Noise sample
+ * @ret rc             Return status code
+ */
+static int linux_get_noise ( noise_sample_t *noise ) {
+       uint8_t byte;
+       ssize_t len;
+
+       /* Read a single byte from entropy source */
+       len = linux_read ( entropy_fd, &byte, sizeof ( byte ) );
+       if ( len < 0 ) {
+               DBGC ( &entropy_fd, "ENTROPY could not read from %s: %s\n",
+                      entropy_filename, linux_strerror ( linux_errno ) );
+               return len;
+       }
+       if ( len == 0 ) {
+               DBGC ( &entropy_fd, "ENTROPY EOF on reading from %s: %s\n",
+                      entropy_filename, linux_strerror ( linux_errno ) );
+               return -EPIPE;
+       }
+       *noise = byte;
+
+       return 0;
+}
+
+PROVIDE_ENTROPY_INLINE ( linux, min_entropy_per_sample );
+PROVIDE_ENTROPY ( linux, entropy_enable, linux_entropy_enable );
+PROVIDE_ENTROPY ( linux, entropy_disable, linux_entropy_disable );
+PROVIDE_ENTROPY ( linux, get_noise, linux_get_noise );