Add get_random_long

From: Daniel Cashman <dcashman@android.com>
https://lkml.org/lkml/2016/2/4/831

Signed-off-by: Bernhard Rosenkraenzer <bero@linaro.org>

2 files changed, 23 insertions, 0 deletions

diff --git a/drivers/char/random.c b/drivers/char/random.c
index 9cd6968e2f92..8fdf201ee87c 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -1741,6 +1741,28 @@ unsigned int get_random_int(void)
 EXPORT_SYMBOL(get_random_int);
 
 /*
+ * Same as get_random_int(), but returns unsigned long.
+ */
+unsigned long get_random_long(void)
+{
+	__u32 *hash;
+	unsigned long ret;
+
+	if (arch_get_random_long(&ret))
+		return ret;
+
+	hash = get_cpu_var(get_random_int_hash);
+
+	hash[0] += current->pid + jiffies + random_get_entropy();
+	md5_transform(hash, random_int_secret);
+	ret = *(unsigned long *)hash;
+	put_cpu_var(get_random_int_hash);
+
+	return ret;
+}
+EXPORT_SYMBOL(get_random_long);
+
+/*
  * randomize_range() returns a start address such that
  *
  *    [...... <range> .....]
diff --git a/include/linux/random.h b/include/linux/random.h
index b05856e16b75..0fe49a14daa5 100644
--- a/include/linux/random.h
+++ b/include/linux/random.h
@@ -23,6 +23,7 @@ extern const struct file_operations random_fops, urandom_fops;
 #endif
 
 unsigned int get_random_int(void);
+unsigned long get_random_long(void);
 unsigned long randomize_range(unsigned long start, unsigned long end, unsigned long len);
 
 u32 prandom_u32(void);