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authorHerbert Xu <herbert@gondor.apana.org.au>2007-12-10 16:18:01 +0800
committerHerbert Xu <herbert@gondor.apana.org.au>2008-01-11 08:16:49 +1100
commit743edf57272fd420348e148bf94f9e48ed6abb70 (patch)
treebe4a96ae7f7f8a6b42bf01cc7a61cb4b5938ab50
parent03bf712fb4defc7831c727d1e32d0269f7f96de0 (diff)
downloadlinux-743edf57272fd420348e148bf94f9e48ed6abb70.tar.bz2
[CRYPTO] aead: Add givcrypt operations
This patch adds the underlying givcrypt operations for aead and associated support elements. The rationale is identical to that of the skcipher givcrypt operations, i.e., sometimes only the algorithm knows how the IV should be generated. A new request type aead_givcrypt_request is added which contains an embedded aead_request structure with two new elements to support this operation. The new elements are seq and giv. The seq field should contain a strictly increasing 64-bit integer which may be used by certain IV generators as an input value. The giv field will be used to store the generated IV. It does not need to obey the alignment requirements of the algorithm because it's not used during the operation. The existing iv field must still be available as it will be used to store intermediate IVs and the output IV if chaining is desired. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
-rw-r--r--crypto/aead.c7
-rw-r--r--include/crypto/aead.h38
-rw-r--r--include/linux/crypto.h5
3 files changed, 50 insertions, 0 deletions
diff --git a/crypto/aead.c b/crypto/aead.c
index f23c2b0ee009..0402b606fcfd 100644
--- a/crypto/aead.c
+++ b/crypto/aead.c
@@ -77,6 +77,11 @@ static unsigned int crypto_aead_ctxsize(struct crypto_alg *alg, u32 type,
return alg->cra_ctxsize;
}
+static int no_givdecrypt(struct aead_givcrypt_request *req)
+{
+ return -ENOSYS;
+}
+
static int crypto_init_aead_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
{
struct aead_alg *alg = &tfm->__crt_alg->cra_aead;
@@ -88,6 +93,8 @@ static int crypto_init_aead_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
crt->setkey = setkey;
crt->encrypt = alg->encrypt;
crt->decrypt = alg->decrypt;
+ crt->givencrypt = alg->givencrypt;
+ crt->givdecrypt = alg->givdecrypt ?: no_givdecrypt;
crt->ivsize = alg->ivsize;
crt->authsize = alg->maxauthsize;
diff --git a/include/crypto/aead.h b/include/crypto/aead.h
new file mode 100644
index 000000000000..083920312da0
--- /dev/null
+++ b/include/crypto/aead.h
@@ -0,0 +1,38 @@
+/*
+ * AEAD: Authenticated Encryption with Associated Data
+ *
+ * Copyright (c) 2007 Herbert Xu <herbert@gondor.apana.org.au>
+ *
+ * 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_AEAD_H
+#define _CRYPTO_AEAD_H
+
+#include <linux/crypto.h>
+#include <linux/kernel.h>
+
+/**
+ * struct aead_givcrypt_request - AEAD request with IV generation
+ * @seq: Sequence number for IV generation
+ * @giv: Space for generated IV
+ * @areq: The AEAD request itself
+ */
+struct aead_givcrypt_request {
+ u64 seq;
+ u8 *giv;
+
+ struct aead_request areq;
+};
+
+static inline struct crypto_aead *aead_givcrypt_reqtfm(
+ struct aead_givcrypt_request *req)
+{
+ return crypto_aead_reqtfm(&req->areq);
+}
+
+#endif /* _CRYPTO_AEAD_H */
diff --git a/include/linux/crypto.h b/include/linux/crypto.h
index 835dcaf3fe4e..7524928bff93 100644
--- a/include/linux/crypto.h
+++ b/include/linux/crypto.h
@@ -106,6 +106,7 @@ struct crypto_blkcipher;
struct crypto_hash;
struct crypto_tfm;
struct crypto_type;
+struct aead_givcrypt_request;
struct skcipher_givcrypt_request;
typedef void (*crypto_completion_t)(struct crypto_async_request *req, int err);
@@ -202,6 +203,8 @@ struct aead_alg {
int (*setauthsize)(struct crypto_aead *tfm, unsigned int authsize);
int (*encrypt)(struct aead_request *req);
int (*decrypt)(struct aead_request *req);
+ int (*givencrypt)(struct aead_givcrypt_request *req);
+ int (*givdecrypt)(struct aead_givcrypt_request *req);
unsigned int ivsize;
unsigned int maxauthsize;
@@ -348,6 +351,8 @@ struct aead_tfm {
unsigned int keylen);
int (*encrypt)(struct aead_request *req);
int (*decrypt)(struct aead_request *req);
+ int (*givencrypt)(struct aead_givcrypt_request *req);
+ int (*givdecrypt)(struct aead_givcrypt_request *req);
unsigned int ivsize;
unsigned int authsize;
unsigned int reqsize;