crypto: rng - Introduce crypto_rng_generate
This patch adds the new top-level function crypto_rng_generate
which generates random numbers with additional input. It also
extends the mid-level rng_gen_random function to take additional
data as input.
Signed-off-by: Herbert Xu <[email protected]>
diff --git a/include/crypto/rng.h b/include/crypto/rng.h
index f13f3fa..f20f068 100644
--- a/include/crypto/rng.h
+++ b/include/crypto/rng.h
@@ -16,7 +16,9 @@
#include <linux/crypto.h>
struct crypto_rng {
- int (*generate)(struct crypto_rng *tfm, u8 *rdata, unsigned int dlen);
+ int (*generate)(struct crypto_rng *tfm,
+ const u8 *src, unsigned int slen,
+ u8 *dst, unsigned int dlen);
int (*seed)(struct crypto_rng *tfm, u8 *seed, unsigned int slen);
struct crypto_tfm base;
};
@@ -83,6 +85,27 @@
}
/**
+ * crypto_rng_generate() - get random number
+ * @tfm: cipher handle
+ * @src: Input buffer holding additional data, may be NULL
+ * @slen: Length of additional data
+ * @dst: output buffer holding the random numbers
+ * @dlen: length of the output buffer
+ *
+ * This function fills the caller-allocated buffer with random
+ * numbers using the random number generator referenced by the
+ * cipher handle.
+ *
+ * Return: 0 function was successful; < 0 if an error occurred
+ */
+static inline int crypto_rng_generate(struct crypto_rng *tfm,
+ const u8 *src, unsigned int slen,
+ u8 *dst, unsigned int dlen)
+{
+ return tfm->generate(tfm, src, slen, dst, dlen);
+}
+
+/**
* crypto_rng_get_bytes() - get random number
* @tfm: cipher handle
* @rdata: output buffer holding the random numbers
@@ -96,7 +119,7 @@
static inline int crypto_rng_get_bytes(struct crypto_rng *tfm,
u8 *rdata, unsigned int dlen)
{
- return tfm->generate(tfm, rdata, dlen);
+ return crypto_rng_generate(tfm, NULL, 0, rdata, dlen);
}
/**
