From b721056e04ddd38564898b323caf8c559bf88cb7 Mon Sep 17 00:00:00 2001
From: Dave Wysochanski <dwysocha@redhat.com>
Date: Sun, 7 Dec 2008 04:23:37 +0000
Subject: [PATCH] Add generic function to read /dev/urandom, used in uuid
 calculation.

---
 WHATS_NEW               |  1 +
 lib/misc/lvm-wrappers.c | 26 ++++++++++++++++++++++++++
 lib/misc/lvm-wrappers.h |  5 +++++
 lib/uuid/uuid.c         | 14 ++------------
 4 files changed, 34 insertions(+), 12 deletions(-)

diff --git a/WHATS_NEW b/WHATS_NEW
index e8dfbced8..9a2bdfa4c 100644
--- a/WHATS_NEW
+++ b/WHATS_NEW
@@ -1,5 +1,6 @@
 Version 2.02.44 - 
 ====================================
+  Add generic function to read /dev/urandom, used in uuid calculation.
   Use displayable_lvs_in_vg and lv_is_displayable for consistency throughout.
   Fix race in vgcreate that would result in second caller overwriting first.
   Fix uninitialised lv_count in vgdisplay -c.
diff --git a/lib/misc/lvm-wrappers.c b/lib/misc/lvm-wrappers.c
index 1d8ca08f2..3ab8a7135 100644
--- a/lib/misc/lvm-wrappers.c
+++ b/lib/misc/lvm-wrappers.c
@@ -15,8 +15,34 @@
 #include "lib.h"
 
 #include <unistd.h>
+#include <fcntl.h>
 
 int lvm_getpagesize(void)
 {
 	return getpagesize();
 }
+
+int read_urandom(void *buf, size_t len)
+{
+	int fd;
+
+	/* FIXME: we should stat here, and handle other cases */
+	/* FIXME: use common _io() routine's open/read/close */
+	if ((fd = open("/dev/urandom", O_RDONLY)) < 0) {
+		log_sys_error("open", "read_urandom: /dev/urandom");
+		return 0;
+	}
+
+	if (read(fd, buf, len) != (ssize_t) len) {
+		log_sys_error("read", "read_urandom: /dev/urandom");
+		if (close(fd))
+			stack;
+		return 0;
+	}
+
+	if (close(fd))
+		stack;
+
+	return 1;
+}
+
diff --git a/lib/misc/lvm-wrappers.h b/lib/misc/lvm-wrappers.h
index 851e73fde..717f2f413 100644
--- a/lib/misc/lvm-wrappers.h
+++ b/lib/misc/lvm-wrappers.h
@@ -18,4 +18,9 @@
 
 int lvm_getpagesize(void);
 
+/*
+ * Read 'len' bytes of entropy from /dev/urandom and store in 'buf'.
+ */
+int read_urandom(void *buf, size_t len);
+
 #endif
diff --git a/lib/uuid/uuid.c b/lib/uuid/uuid.c
index 39252c0e5..1ded223fa 100644
--- a/lib/uuid/uuid.c
+++ b/lib/uuid/uuid.c
@@ -15,6 +15,7 @@
 
 #include "lib.h"
 #include "uuid.h"
+#include "lvm-wrappers.h"
 
 #include <assert.h>
 #include <sys/stat.h>
@@ -94,25 +95,14 @@ int lvid_in_restricted_range(union lvid *lvid)
 
 int id_create(struct id *id)
 {
-	int randomfile;
 	unsigned i;
 	size_t len = sizeof(id->uuid);
 
 	memset(id->uuid, 0, len);
-	if ((randomfile = open("/dev/urandom", O_RDONLY)) < 0) {
-		log_sys_error("open", "id_create: /dev/urandom");
+	if (!read_urandom(&id->uuid, len)) {
 		return 0;
 	}
 
-	if (read(randomfile, id->uuid, len) != (ssize_t) len) {
-		log_sys_error("read", "id_create: /dev/urandom");
-		if (close(randomfile))
-			stack;
-		return 0;
-	}
-	if (close(randomfile))
-		stack;
-
 	/*
 	 * Skip out the last 2 chars in randomized creation for LVM1
 	 * backwards compatibility.