crypto: rng - RNG interface and implementation
This patch adds a random number generator interface as well as a
cryptographic pseudo-random number generator based on AES. It is
meant to be used in cases where a deterministic CPRNG is required.
One of the first applications will be as an input in the IPsec IV
generation process.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/include/crypto/internal/rng.h b/include/crypto/internal/rng.h
new file mode 100644
index 0000000..8969733
--- /dev/null
+++ b/include/crypto/internal/rng.h
@@ -0,0 +1,26 @@
+/*
+ * RNG: Random Number Generator algorithms under the crypto API
+ *
+ * Copyright (c) 2008 Neil Horman <nhorman@tuxdriver.com>
+ *
+ * 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 (at your option)
+ * any later version.
+ *
+ */
+
+#ifndef _CRYPTO_INTERNAL_RNG_H
+#define _CRYPTO_INTERNAL_RNG_H
+
+#include <crypto/algapi.h>
+#include <crypto/rng.h>
+
+extern const struct crypto_type crypto_rng_type;
+
+static inline void *crypto_rng_ctx(struct crypto_rng *tfm)
+{
+ return crypto_tfm_ctx(&tfm->base);
+}
+
+#endif
diff --git a/include/crypto/rng.h b/include/crypto/rng.h
new file mode 100644
index 0000000..c93f9b9
--- /dev/null
+++ b/include/crypto/rng.h
@@ -0,0 +1,75 @@
+/*
+ * RNG: Random Number Generator algorithms under the crypto API
+ *
+ * Copyright (c) 2008 Neil Horman <nhorman@tuxdriver.com>
+ *
+ * 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 (at your option)
+ * any later version.
+ *
+ */
+
+#ifndef _CRYPTO_RNG_H
+#define _CRYPTO_RNG_H
+
+#include <linux/crypto.h>
+
+extern struct crypto_rng *crypto_default_rng;
+
+int crypto_get_default_rng(void);
+void crypto_put_default_rng(void);
+
+static inline struct crypto_rng *__crypto_rng_cast(struct crypto_tfm *tfm)
+{
+ return (struct crypto_rng *)tfm;
+}
+
+static inline struct crypto_rng *crypto_alloc_rng(const char *alg_name,
+ u32 type, u32 mask)
+{
+ type &= ~CRYPTO_ALG_TYPE_MASK;
+ type |= CRYPTO_ALG_TYPE_RNG;
+ mask |= CRYPTO_ALG_TYPE_MASK;
+
+ return __crypto_rng_cast(crypto_alloc_base(alg_name, type, mask));
+}
+
+static inline struct crypto_tfm *crypto_rng_tfm(struct crypto_rng *tfm)
+{
+ return &tfm->base;
+}
+
+static inline struct rng_alg *crypto_rng_alg(struct crypto_rng *tfm)
+{
+ return &crypto_rng_tfm(tfm)->__crt_alg->cra_rng;
+}
+
+static inline struct rng_tfm *crypto_rng_crt(struct crypto_rng *tfm)
+{
+ return &crypto_rng_tfm(tfm)->crt_rng;
+}
+
+static inline void crypto_free_rng(struct crypto_rng *tfm)
+{
+ crypto_free_tfm(crypto_rng_tfm(tfm));
+}
+
+static inline int crypto_rng_get_bytes(struct crypto_rng *tfm,
+ u8 *rdata, unsigned int dlen)
+{
+ return crypto_rng_crt(tfm)->rng_gen_random(tfm, rdata, dlen);
+}
+
+static inline int crypto_rng_reset(struct crypto_rng *tfm,
+ u8 *seed, unsigned int slen)
+{
+ return crypto_rng_crt(tfm)->rng_reset(tfm, seed, slen);
+}
+
+static inline int crypto_rng_seedsize(struct crypto_rng *tfm)
+{
+ return crypto_rng_alg(tfm)->seedsize;
+}
+
+#endif
diff --git a/include/linux/crypto.h b/include/linux/crypto.h
index 81d994a..3d2317e 100644
--- a/include/linux/crypto.h
+++ b/include/linux/crypto.h
@@ -38,6 +38,7 @@
#define CRYPTO_ALG_TYPE_DIGEST 0x00000008
#define CRYPTO_ALG_TYPE_HASH 0x00000009
#define CRYPTO_ALG_TYPE_AHASH 0x0000000a
+#define CRYPTO_ALG_TYPE_RNG 0x0000000c
#define CRYPTO_ALG_TYPE_HASH_MASK 0x0000000e
#define CRYPTO_ALG_TYPE_AHASH_MASK 0x0000000c
@@ -113,6 +114,7 @@
struct crypto_blkcipher;
struct crypto_hash;
struct crypto_ahash;
+struct crypto_rng;
struct crypto_tfm;
struct crypto_type;
struct aead_givcrypt_request;
@@ -298,6 +300,15 @@
unsigned int slen, u8 *dst, unsigned int *dlen);
};
+struct rng_alg {
+ int (*rng_make_random)(struct crypto_rng *tfm, u8 *rdata,
+ unsigned int dlen);
+ int (*rng_reset)(struct crypto_rng *tfm, u8 *seed, unsigned int slen);
+
+ unsigned int seedsize;
+};
+
+
#define cra_ablkcipher cra_u.ablkcipher
#define cra_aead cra_u.aead
#define cra_blkcipher cra_u.blkcipher
@@ -306,6 +317,7 @@
#define cra_hash cra_u.hash
#define cra_ahash cra_u.ahash
#define cra_compress cra_u.compress
+#define cra_rng cra_u.rng
struct crypto_alg {
struct list_head cra_list;
@@ -333,6 +345,7 @@
struct hash_alg hash;
struct ahash_alg ahash;
struct compress_alg compress;
+ struct rng_alg rng;
} cra_u;
int (*cra_init)(struct crypto_tfm *tfm);
@@ -438,6 +451,12 @@
u8 *dst, unsigned int *dlen);
};
+struct rng_tfm {
+ int (*rng_gen_random)(struct crypto_rng *tfm, u8 *rdata,
+ unsigned int dlen);
+ int (*rng_reset)(struct crypto_rng *tfm, u8 *seed, unsigned int slen);
+};
+
#define crt_ablkcipher crt_u.ablkcipher
#define crt_aead crt_u.aead
#define crt_blkcipher crt_u.blkcipher
@@ -445,6 +464,7 @@
#define crt_hash crt_u.hash
#define crt_ahash crt_u.ahash
#define crt_compress crt_u.compress
+#define crt_rng crt_u.rng
struct crypto_tfm {
@@ -458,6 +478,7 @@
struct hash_tfm hash;
struct ahash_tfm ahash;
struct compress_tfm compress;
+ struct rng_tfm rng;
} crt_u;
struct crypto_alg *__crt_alg;
@@ -489,6 +510,10 @@
struct crypto_tfm base;
};
+struct crypto_rng {
+ struct crypto_tfm base;
+};
+
enum {
CRYPTOA_UNSPEC,
CRYPTOA_ALG,