Linux cryptographic layer development
 help / color / mirror / Atom feed
* [PATCH v8 1/3] crypto: Key-agreement Protocol Primitives API (KPP)
From: Salvatore Benedetto @ 2016-06-13 21:55 UTC (permalink / raw)
  To: herbert; +Cc: salvatore.benedetto, linux-crypto
In-Reply-To: <1465854948-9084-1-git-send-email-salvatore.benedetto@intel.com>

Add key-agreement protocol primitives (kpp) API which allows to
implement primitives required by protocols such as DH and ECDH.
The API is composed mainly by the following functions
 * set_secret() - It allows the user to set his secret, also
   referred to as his private key, along with the parameters
   known to both parties involved in the key-agreement session.
 * generate_public_key() - It generates the public key to be sent to
   the other counterpart involved in the key-agreement session. The
   function has to be called after set_params() and set_secret()
 * generate_secret() - It generates the shared secret for the session

Other functions such as init() and exit() are provided for allowing
cryptographic hardware to be inizialized properly before use

Signed-off-by: Salvatore Benedetto <salvatore.benedetto@intel.com>
---
 crypto/Kconfig                  |  10 ++
 crypto/Makefile                 |   1 +
 crypto/crypto_user.c            |  20 +++
 crypto/kpp.c                    | 123 ++++++++++++++++
 include/crypto/internal/kpp.h   |  64 +++++++++
 include/crypto/kpp.h            | 310 ++++++++++++++++++++++++++++++++++++++++
 include/linux/crypto.h          |   1 +
 include/uapi/linux/cryptouser.h |   5 +
 8 files changed, 534 insertions(+)
 create mode 100644 crypto/kpp.c
 create mode 100644 include/crypto/internal/kpp.h
 create mode 100644 include/crypto/kpp.h

diff --git a/crypto/Kconfig b/crypto/Kconfig
index 1d33beb..0bd6d7f 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -93,6 +93,15 @@ config CRYPTO_AKCIPHER
 	select CRYPTO_AKCIPHER2
 	select CRYPTO_ALGAPI
 
+config CRYPTO_KPP2
+	tristate
+	select CRYPTO_ALGAPI2
+
+config CRYPTO_KPP
+	tristate
+	select CRYPTO_ALGAPI
+	select CRYPTO_KPP2
+
 config CRYPTO_RSA
 	tristate "RSA algorithm"
 	select CRYPTO_AKCIPHER
@@ -115,6 +124,7 @@ config CRYPTO_MANAGER2
 	select CRYPTO_HASH2
 	select CRYPTO_BLKCIPHER2
 	select CRYPTO_AKCIPHER2
+	select CRYPTO_KPP2
 
 config CRYPTO_USER
 	tristate "Userspace cryptographic algorithm configuration"
diff --git a/crypto/Makefile b/crypto/Makefile
index 4f4ef7e..5b60890 100644
--- a/crypto/Makefile
+++ b/crypto/Makefile
@@ -30,6 +30,7 @@ crypto_hash-y += shash.o
 obj-$(CONFIG_CRYPTO_HASH2) += crypto_hash.o
 
 obj-$(CONFIG_CRYPTO_AKCIPHER2) += akcipher.o
+obj-$(CONFIG_CRYPTO_KPP2) += kpp.o
 
 $(obj)/rsapubkey-asn1.o: $(obj)/rsapubkey-asn1.c $(obj)/rsapubkey-asn1.h
 $(obj)/rsaprivkey-asn1.o: $(obj)/rsaprivkey-asn1.c $(obj)/rsaprivkey-asn1.h
diff --git a/crypto/crypto_user.c b/crypto/crypto_user.c
index f71960d..e7a0a9d 100644
--- a/crypto/crypto_user.c
+++ b/crypto/crypto_user.c
@@ -28,6 +28,7 @@
 #include <crypto/internal/skcipher.h>
 #include <crypto/internal/rng.h>
 #include <crypto/akcipher.h>
+#include <crypto/kpp.h>
 
 #include "internal.h"
 
@@ -126,6 +127,21 @@ nla_put_failure:
 	return -EMSGSIZE;
 }
 
+static int crypto_report_kpp(struct sk_buff *skb, struct crypto_alg *alg)
+{
+	struct crypto_report_kpp rkpp;
+
+	strncpy(rkpp.type, "kpp", sizeof(rkpp.type));
+
+	if (nla_put(skb, CRYPTOCFGA_REPORT_KPP,
+		    sizeof(struct crypto_report_kpp), &rkpp))
+		goto nla_put_failure;
+	return 0;
+
+nla_put_failure:
+	return -EMSGSIZE;
+}
+
 static int crypto_report_one(struct crypto_alg *alg,
 			     struct crypto_user_alg *ualg, struct sk_buff *skb)
 {
@@ -176,6 +192,10 @@ static int crypto_report_one(struct crypto_alg *alg,
 			goto nla_put_failure;
 
 		break;
+	case CRYPTO_ALG_TYPE_KPP:
+		if (crypto_report_kpp(skb, alg))
+			goto nla_put_failure;
+		break;
 	}
 
 out:
diff --git a/crypto/kpp.c b/crypto/kpp.c
new file mode 100644
index 0000000..d36ce05
--- /dev/null
+++ b/crypto/kpp.c
@@ -0,0 +1,123 @@
+/*
+ * Key-agreement Protocol Primitives (KPP)
+ *
+ * Copyright (c) 2016, Intel Corporation
+ * Authors: Salvatore Benedetto <salvatore.benedetto@intel.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.
+ *
+ */
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/seq_file.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/crypto.h>
+#include <crypto/algapi.h>
+#include <linux/cryptouser.h>
+#include <net/netlink.h>
+#include <crypto/kpp.h>
+#include <crypto/internal/kpp.h>
+#include "internal.h"
+
+#ifdef CONFIG_NET
+static int crypto_kpp_report(struct sk_buff *skb, struct crypto_alg *alg)
+{
+	struct crypto_report_kpp rkpp;
+
+	strncpy(rkpp.type, "kpp", sizeof(rkpp.type));
+
+	if (nla_put(skb, CRYPTOCFGA_REPORT_KPP,
+		    sizeof(struct crypto_report_kpp), &rkpp))
+		goto nla_put_failure;
+	return 0;
+
+nla_put_failure:
+	return -EMSGSIZE;
+}
+#else
+static int crypto_kpp_report(struct sk_buff *skb, struct crypto_alg *alg)
+{
+	return -ENOSYS;
+}
+#endif
+
+static void crypto_kpp_show(struct seq_file *m, struct crypto_alg *alg)
+	__attribute__ ((unused));
+
+static void crypto_kpp_show(struct seq_file *m, struct crypto_alg *alg)
+{
+	seq_puts(m, "type         : kpp\n");
+}
+
+static void crypto_kpp_exit_tfm(struct crypto_tfm *tfm)
+{
+	struct crypto_kpp *kpp = __crypto_kpp_tfm(tfm);
+	struct kpp_alg *alg = crypto_kpp_alg(kpp);
+
+	alg->exit(kpp);
+}
+
+static int crypto_kpp_init_tfm(struct crypto_tfm *tfm)
+{
+	struct crypto_kpp *kpp = __crypto_kpp_tfm(tfm);
+	struct kpp_alg *alg = crypto_kpp_alg(kpp);
+
+	if (alg->exit)
+		kpp->base.exit = crypto_kpp_exit_tfm;
+
+	if (alg->init)
+		return alg->init(kpp);
+
+	return 0;
+}
+
+static const struct crypto_type crypto_kpp_type = {
+	.extsize = crypto_alg_extsize,
+	.init_tfm = crypto_kpp_init_tfm,
+#ifdef CONFIG_PROC_FS
+	.show = crypto_kpp_show,
+#endif
+	.report = crypto_kpp_report,
+	.maskclear = ~CRYPTO_ALG_TYPE_MASK,
+	.maskset = CRYPTO_ALG_TYPE_MASK,
+	.type = CRYPTO_ALG_TYPE_KPP,
+	.tfmsize = offsetof(struct crypto_kpp, base),
+};
+
+struct crypto_kpp *crypto_alloc_kpp(const char *alg_name, u32 type, u32 mask)
+{
+	return crypto_alloc_tfm(alg_name, &crypto_kpp_type, type, mask);
+}
+EXPORT_SYMBOL_GPL(crypto_alloc_kpp);
+
+static void kpp_prepare_alg(struct kpp_alg *alg)
+{
+	struct crypto_alg *base = &alg->base;
+
+	base->cra_type = &crypto_kpp_type;
+	base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
+	base->cra_flags |= CRYPTO_ALG_TYPE_KPP;
+}
+
+int crypto_register_kpp(struct kpp_alg *alg)
+{
+	struct crypto_alg *base = &alg->base;
+
+	kpp_prepare_alg(alg);
+	return crypto_register_alg(base);
+}
+EXPORT_SYMBOL_GPL(crypto_register_kpp);
+
+void crypto_unregister_kpp(struct kpp_alg *alg)
+{
+	crypto_unregister_alg(&alg->base);
+}
+EXPORT_SYMBOL_GPL(crypto_unregister_kpp);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Key-agreement Protocol Primitives");
diff --git a/include/crypto/internal/kpp.h b/include/crypto/internal/kpp.h
new file mode 100644
index 0000000..ad3acf3
--- /dev/null
+++ b/include/crypto/internal/kpp.h
@@ -0,0 +1,64 @@
+/*
+ * Key-agreement Protocol Primitives (KPP)
+ *
+ * Copyright (c) 2016, Intel Corporation
+ * Authors: Salvatore Benedetto <salvatore.benedetto@intel.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_KPP_INT_H
+#define _CRYPTO_KPP_INT_H
+#include <crypto/kpp.h>
+#include <crypto/algapi.h>
+
+/*
+ * Transform internal helpers.
+ */
+static inline void *kpp_request_ctx(struct kpp_request *req)
+{
+	return req->__ctx;
+}
+
+static inline void *kpp_tfm_ctx(struct crypto_kpp *tfm)
+{
+	return tfm->base.__crt_ctx;
+}
+
+static inline void kpp_request_complete(struct kpp_request *req, int err)
+{
+	req->base.complete(&req->base, err);
+}
+
+static inline const char *kpp_alg_name(struct crypto_kpp *tfm)
+{
+	return crypto_kpp_tfm(tfm)->__crt_alg->cra_name;
+}
+
+/**
+ * crypto_register_kpp() -- Register key-agreement protocol primitives algorithm
+ *
+ * Function registers an implementation of a key-agreement protocol primitive
+ * algorithm
+ *
+ * @alg:	algorithm definition
+ *
+ * Return: zero on success; error code in case of error
+ */
+int crypto_register_kpp(struct kpp_alg *alg);
+
+/**
+ * crypto_unregister_kpp() -- Unregister key-agreement protocol primitive
+ * algorithm
+ *
+ * Function unregisters an implementation of a key-agreement protocol primitive
+ * algorithm
+ *
+ * @alg:	algorithm definition
+ */
+void crypto_unregister_kpp(struct kpp_alg *alg);
+
+#endif
diff --git a/include/crypto/kpp.h b/include/crypto/kpp.h
new file mode 100644
index 0000000..90436d0
--- /dev/null
+++ b/include/crypto/kpp.h
@@ -0,0 +1,310 @@
+/*
+ * Key-agreement Protocol Primitives (KPP)
+ *
+ * Copyright (c) 2016, Intel Corporation
+ * Authors: Salvatore Benedetto <salvatore.benedetto@intel.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_KPP_
+#define _CRYPTO_KPP_
+#include <linux/crypto.h>
+
+/**
+ * struct kpp_request
+ *
+ * @base:	Common attributes for async crypto requests
+ * @src:	Source data
+ * @dst:	Destination data
+ * @src_len:	Size of the input buffer
+ * @dst_len:	Size of the output buffer. It needs to be at least
+ *		as big as the expected result depending	on the operation
+ *		After operation it will be updated with the actual size of the
+ *		result. In case of error where the dst sgl size was insufficient,
+ *		it will be updated to the size required for the operation.
+ * @__ctx:	Start of private context data
+ */
+struct kpp_request {
+	struct crypto_async_request base;
+	struct scatterlist *src;
+	struct scatterlist *dst;
+	unsigned int src_len;
+	unsigned int dst_len;
+	void *__ctx[] CRYPTO_MINALIGN_ATTR;
+};
+
+/**
+ * struct crypto_kpp - user-instantiated object which encapsulate
+ * algorithms and core processing logic
+ *
+ * @base:	Common crypto API algorithm data structure
+ */
+struct crypto_kpp {
+	struct crypto_tfm base;
+};
+
+/**
+ * struct kpp_alg - generic key-agreement protocol primitives
+ *
+ * @set_secret:		Function invokes the protocol specific function to
+ *			store the secret private key along with parameters.
+ *			The implementation knows how to decode thie buffer
+ * @generate_public_key: Function generate the public key to be sent to the
+ *			counterpart. In case of error, where output is not big
+ *			enough req->dst_len will be updated to the size
+ *			required
+ * @compute_shared_secret: Function compute the shared secret as defined by
+ *			the algorithm. The result is given back to the user.
+ *			In case of error, where output is not big enough,
+ *			req->dst_len will be updated to the size required
+ * @max_size:		Function returns the size of the output buffer
+ * @init:		Initialize the object. This is called only once at
+ *			instantiation time. In case the cryptographic hardware
+ *			needs to be initialized. Software fallback should be
+ *			put in place here.
+ * @exit:		Undo everything @init did.
+ *
+ * @reqsize:		Request context size required by algorithm
+ *			implementation
+ * @base		Common crypto API algorithm data structure
+ */
+struct kpp_alg {
+	int (*set_secret)(struct crypto_kpp *tfm, void *buffer);
+	int (*generate_public_key)(struct kpp_request *req);
+	int (*compute_shared_secret)(struct kpp_request *req);
+
+	int (*max_size)(struct crypto_kpp *tfm);
+
+	int (*init)(struct crypto_kpp *tfm);
+	void (*exit)(struct crypto_kpp *tfm);
+
+	unsigned int reqsize;
+	struct crypto_alg base;
+};
+
+/**
+ * DOC: Generic Key-agreement Protocol Primitevs API
+ *
+ * The KPP API is used with the algorithm type
+ * CRYPTO_ALG_TYPE_KPP (listed as type "kpp" in /proc/crypto)
+ */
+
+/**
+ * crypto_alloc_kpp() - allocate KPP tfm handle
+ * @alg_name: is the name of the kpp algorithm (e.g. "dh", "ecdh")
+ * @type: specifies the type of the algorithm
+ * @mask: specifies the mask for the algorithm
+ *
+ * Allocate a handle for kpp algorithm. The returned struct crypto_kpp
+ * is requeried for any following API invocation
+ *
+ * Return: allocated handle in case of success; IS_ERR() is true in case of
+ *	   an error, PTR_ERR() returns the error code.
+ */
+struct crypto_kpp *crypto_alloc_kpp(const char *alg_name, u32 type, u32 mask);
+
+static inline struct crypto_tfm *crypto_kpp_tfm(struct crypto_kpp *tfm)
+{
+	return &tfm->base;
+}
+
+static inline struct kpp_alg *__crypto_kpp_alg(struct crypto_alg *alg)
+{
+	return container_of(alg, struct kpp_alg, base);
+}
+
+static inline struct crypto_kpp *__crypto_kpp_tfm(struct crypto_tfm *tfm)
+{
+	return container_of(tfm, struct crypto_kpp, base);
+}
+
+static inline struct kpp_alg *crypto_kpp_alg(struct crypto_kpp *tfm)
+{
+	return __crypto_kpp_alg(crypto_kpp_tfm(tfm)->__crt_alg);
+}
+
+static inline unsigned int crypto_kpp_reqsize(struct crypto_kpp *tfm)
+{
+	return crypto_kpp_alg(tfm)->reqsize;
+}
+
+static inline void kpp_request_set_tfm(struct kpp_request *req,
+				       struct crypto_kpp *tfm)
+{
+	req->base.tfm = crypto_kpp_tfm(tfm);
+}
+
+static inline struct crypto_kpp *crypto_kpp_reqtfm(struct kpp_request *req)
+{
+	return __crypto_kpp_tfm(req->base.tfm);
+}
+
+/**
+ * crypto_free_kpp() - free KPP tfm handle
+ *
+ * @tfm: KPP tfm handle allocated with crypto_alloc_kpp()
+ */
+static inline void crypto_free_kpp(struct crypto_kpp *tfm)
+{
+	crypto_destroy_tfm(tfm, crypto_kpp_tfm(tfm));
+}
+
+/**
+ * kpp_request_alloc() - allocates kpp request
+ *
+ * @tfm:	KPP tfm handle allocated with crypto_alloc_kpp()
+ * @gfp:	allocation flags
+ *
+ * Return: allocated handle in case of success or NULL in case of an error.
+ */
+static inline struct kpp_request *kpp_request_alloc(struct crypto_kpp *tfm,
+						    gfp_t gfp)
+{
+	struct kpp_request *req;
+
+	req = kmalloc(sizeof(*req) + crypto_kpp_reqsize(tfm), gfp);
+	if (likely(req))
+		kpp_request_set_tfm(req, tfm);
+
+	return req;
+}
+
+/**
+ * kpp_request_free() - zeroize and free kpp request
+ *
+ * @req:	request to free
+ */
+static inline void kpp_request_free(struct kpp_request *req)
+{
+	kzfree(req);
+}
+
+/**
+ * kpp_request_set_callback() - Sets an asynchronous callback.
+ *
+ * Callback will be called when an asynchronous operation on a given
+ * request is finished.
+ *
+ * @req:	request that the callback will be set for
+ * @flgs:	specify for instance if the operation may backlog
+ * @cmpl:	callback which will be called
+ * @data:	private data used by the caller
+ */
+static inline void kpp_request_set_callback(struct kpp_request *req,
+					    u32 flgs,
+					    crypto_completion_t cmpl,
+					    void *data)
+{
+	req->base.complete = cmpl;
+	req->base.data = data;
+	req->base.flags = flgs;
+}
+
+/**
+ * kpp_request_set_input() - Sets input buffer
+ *
+ * Sets parameters required by generate_public_key
+ *
+ * @req:	kpp request
+ * @input:	ptr to input scatter list
+ * @input_len:	size of the input scatter list
+ */
+static inline void kpp_request_set_input(struct kpp_request *req,
+					 struct scatterlist *input,
+					 unsigned int input_len)
+{
+	req->src = input;
+	req->src_len = input_len;
+}
+
+/**
+ * kpp_request_set_output() - Sets output buffer
+ *
+ * Sets parameters required by kpp operation
+ *
+ * @req:	kpp request
+ * @output:	ptr to output scatter list
+ * @output_len:	size of the output scatter list
+ */
+static inline void kpp_request_set_output(struct kpp_request *req,
+					  struct scatterlist *output,
+					  unsigned int output_len)
+{
+	req->dst = output;
+	req->dst_len = output_len;
+}
+
+/**
+ * crypto_kpp_set_secret() - Invoke kpp operation
+ *
+ * Function invokes the specific kpp operation for a given alg.
+ *
+ * @tfm:	tfm handle
+ *
+ * Return: zero on success; error code in case of error
+ */
+static inline int crypto_kpp_set_secret(struct crypto_kpp *tfm, void *buffer)
+{
+	struct kpp_alg *alg = crypto_kpp_alg(tfm);
+
+	return alg->set_secret(tfm, buffer);
+}
+
+/**
+ * crypto_kpp_generate_public_key() - Invoke kpp operation
+ *
+ * Function invokes the specific kpp operation for generating the public part
+ * for a given kpp algorithm
+ *
+ * @req:	kpp key request
+ *
+ * Return: zero on success; error code in case of error
+ */
+static inline int crypto_kpp_generate_public_key(struct kpp_request *req)
+{
+	struct crypto_kpp *tfm = crypto_kpp_reqtfm(req);
+	struct kpp_alg *alg = crypto_kpp_alg(tfm);
+
+	return alg->generate_public_key(req);
+}
+
+/**
+ * crypto_kpp_compute_shared_secret() - Invoke kpp operation
+ *
+ * Function invokes the specific kpp operation for computing the shared secret
+ * for a given kpp algorithm.
+ *
+ * @req:	kpp key request
+ *
+ * Return: zero on success; error code in case of error
+ */
+static inline int crypto_kpp_compute_shared_secret(struct kpp_request *req)
+{
+	struct crypto_kpp *tfm = crypto_kpp_reqtfm(req);
+	struct kpp_alg *alg = crypto_kpp_alg(tfm);
+
+	return alg->compute_shared_secret(req);
+}
+
+/**
+ * crypto_kpp_maxsize() - Get len for output buffer
+ *
+ * Function returns the output buffer size required
+ *
+ * @tfm:	KPP tfm handle allocated with crypto_alloc_kpp()
+ *
+ * Return: minimum len for output buffer or error code if key hasn't been set
+ */
+static inline int crypto_kpp_maxsize(struct crypto_kpp *tfm)
+{
+	struct kpp_alg *alg = crypto_kpp_alg(tfm);
+
+	return alg->max_size(tfm);
+}
+
+#endif
diff --git a/include/linux/crypto.h b/include/linux/crypto.h
index d844cbc..992cfc2 100644
--- a/include/linux/crypto.h
+++ b/include/linux/crypto.h
@@ -48,6 +48,7 @@
 #define CRYPTO_ALG_TYPE_BLKCIPHER	0x00000004
 #define CRYPTO_ALG_TYPE_ABLKCIPHER	0x00000005
 #define CRYPTO_ALG_TYPE_GIVCIPHER	0x00000006
+#define CRYPTO_ALG_TYPE_KPP		0x00000008
 #define CRYPTO_ALG_TYPE_RNG		0x0000000c
 #define CRYPTO_ALG_TYPE_AKCIPHER	0x0000000d
 #define CRYPTO_ALG_TYPE_DIGEST		0x0000000e
diff --git a/include/uapi/linux/cryptouser.h b/include/uapi/linux/cryptouser.h
index 2e67bb6..79b5ded 100644
--- a/include/uapi/linux/cryptouser.h
+++ b/include/uapi/linux/cryptouser.h
@@ -45,6 +45,7 @@ enum crypto_attr_type_t {
 	CRYPTOCFGA_REPORT_RNG,		/* struct crypto_report_rng */
 	CRYPTOCFGA_REPORT_CIPHER,	/* struct crypto_report_cipher */
 	CRYPTOCFGA_REPORT_AKCIPHER,	/* struct crypto_report_akcipher */
+	CRYPTOCFGA_REPORT_KPP,		/* struct crypto_report_kpp */
 	__CRYPTOCFGA_MAX
 
 #define CRYPTOCFGA_MAX (__CRYPTOCFGA_MAX - 1)
@@ -107,5 +108,9 @@ struct crypto_report_akcipher {
 	char type[CRYPTO_MAX_NAME];
 };
 
+struct crypto_report_kpp {
+	char type[CRYPTO_MAX_NAME];
+};
+
 #define CRYPTO_REPORT_MAXSIZE (sizeof(struct crypto_user_alg) + \
 			       sizeof(struct crypto_report_blkcipher))
-- 
2.7.4

^ permalink raw reply related

* [PATCH v8 2/3] crypto: kpp - Add DH software implementation
From: Salvatore Benedetto @ 2016-06-13 21:55 UTC (permalink / raw)
  To: herbert; +Cc: salvatore.benedetto, linux-crypto
In-Reply-To: <1465854948-9084-1-git-send-email-salvatore.benedetto@intel.com>

 * Implement MPI based Diffie-Hellman under kpp API
 * Test provided uses data generad by OpenSSL

Signed-off-by: Salvatore Benedetto <salvatore.benedetto@intel.com>
---
 crypto/Kconfig      |   8 ++
 crypto/Makefile     |   2 +
 crypto/dh.c         | 189 +++++++++++++++++++++++++++++++++++++++++++++++
 crypto/testmgr.c    | 157 +++++++++++++++++++++++++++++++++++++++
 crypto/testmgr.h    | 208 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 include/crypto/dh.h |  25 +++++++
 6 files changed, 589 insertions(+)
 create mode 100644 crypto/dh.c
 create mode 100644 include/crypto/dh.h

diff --git a/crypto/Kconfig b/crypto/Kconfig
index 0bd6d7f..4190e0d 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -111,6 +111,14 @@ config CRYPTO_RSA
 	help
 	  Generic implementation of the RSA public key algorithm.
 
+config CRYPTO_DH
+	tristate "Diffie-Hellman algorithm"
+	select CRYPTO_KPP
+	select MPILIB
+	help
+	  Generic implementation of the Diffie-Hellman algorithm.
+
+
 config CRYPTO_MANAGER
 	tristate "Cryptographic algorithm manager"
 	select CRYPTO_MANAGER2
diff --git a/crypto/Makefile b/crypto/Makefile
index 5b60890..101f8fd 100644
--- a/crypto/Makefile
+++ b/crypto/Makefile
@@ -32,6 +32,8 @@ obj-$(CONFIG_CRYPTO_HASH2) += crypto_hash.o
 obj-$(CONFIG_CRYPTO_AKCIPHER2) += akcipher.o
 obj-$(CONFIG_CRYPTO_KPP2) += kpp.o
 
+obj-$(CONFIG_CRYPTO_DH) += dh.o
+
 $(obj)/rsapubkey-asn1.o: $(obj)/rsapubkey-asn1.c $(obj)/rsapubkey-asn1.h
 $(obj)/rsaprivkey-asn1.o: $(obj)/rsaprivkey-asn1.c $(obj)/rsaprivkey-asn1.h
 clean-files += rsapubkey-asn1.c rsapubkey-asn1.h
diff --git a/crypto/dh.c b/crypto/dh.c
new file mode 100644
index 0000000..7d29056
--- /dev/null
+++ b/crypto/dh.c
@@ -0,0 +1,189 @@
+/*  Diffie-Hellman Key Agreement Method [RFC2631]
+ *
+ * Copyright (c) 2016, Intel Corporation
+ * Authors: Salvatore Benedetto <salvatore.benedetto@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <crypto/internal/kpp.h>
+#include <crypto/kpp.h>
+#include <crypto/dh.h>
+#include <linux/mpi.h>
+
+struct dh_ctx {
+	MPI p;
+	MPI g;
+	MPI xa;
+};
+
+static inline void dh_clear_params(struct dh_ctx *ctx)
+{
+	mpi_free(ctx->p);
+	mpi_free(ctx->g);
+	ctx->p = NULL;
+	ctx->g = NULL;
+}
+
+static void dh_free_ctx(struct dh_ctx *ctx)
+{
+	dh_clear_params(ctx);
+	mpi_free(ctx->xa);
+	ctx->xa = NULL;
+}
+
+/*
+ * If base is g we compute the public key
+ *	ya = g^xa mod p; [RFC2631 sec 2.1.1]
+ * else if base if the counterpart public key we compute the shared secret
+ *	ZZ = yb^xa mod p; [RFC2631 sec 2.1.1]
+ */
+static int _compute_val(const struct dh_ctx *ctx, MPI base, MPI val)
+{
+	/* val = base^xa mod p */
+	return mpi_powm(val, base, ctx->xa, ctx->p);
+}
+
+static inline struct dh_ctx *dh_get_ctx(struct crypto_kpp *tfm)
+{
+	return kpp_tfm_ctx(tfm);
+}
+
+static int dh_check_params_length(unsigned int p_len)
+{
+	return (p_len < 1536) ? -EINVAL : 0;
+}
+
+static int dh_set_params(struct dh_ctx *ctx, struct dh *params)
+{
+	if (unlikely(!params->p || !params->g))
+		return -EINVAL;
+
+	if (dh_check_params_length(params->p_size << 3))
+		return -EINVAL;
+
+	ctx->p = mpi_read_raw_data(params->p, params->p_size);
+	if (!ctx->p)
+		return -EINVAL;
+
+	ctx->g = mpi_read_raw_data(params->g, params->g_size);
+	if (!ctx->g) {
+		mpi_free(ctx->p);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int dh_set_secret(struct crypto_kpp *tfm, void *buffer)
+{
+	struct dh_ctx *ctx = dh_get_ctx(tfm);
+	struct dh *params = (struct dh *)buffer;
+
+	if (unlikely(!buffer))
+		return -EINVAL;
+
+	if (dh_set_params(ctx, params) < 0)
+		return -EINVAL;
+
+	ctx->xa = mpi_read_raw_data(params->key, params->key_size);
+	if (!ctx->xa) {
+		dh_clear_params(ctx);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int dh_compute_value(struct kpp_request *req)
+{
+	struct crypto_kpp *tfm = crypto_kpp_reqtfm(req);
+	struct dh_ctx *ctx = dh_get_ctx(tfm);
+	MPI base, val = mpi_alloc(0);
+	int ret = 0;
+	int sign;
+
+	if (!val)
+		return -ENOMEM;
+
+	if (unlikely(!ctx->xa)) {
+		ret = -EINVAL;
+		goto err_free_val;
+	}
+
+	if (req->src) {
+		base = mpi_read_raw_from_sgl(req->src, req->src_len);
+		if (!base) {
+			ret = EINVAL;
+			goto err_free_val;
+		}
+	} else {
+		base = ctx->g;
+	}
+
+	ret = _compute_val(ctx, base, val);
+	if (ret)
+		goto err_free_base;
+
+	ret = mpi_write_to_sgl(val, req->dst, &req->dst_len, &sign);
+	if (ret)
+		goto err_free_base;
+
+	if (sign < 0)
+		ret = -EBADMSG;
+err_free_base:
+	if (req->src)
+		mpi_free(base);
+err_free_val:
+	mpi_free(val);
+	return ret;
+}
+
+static int dh_max_size(struct crypto_kpp *tfm)
+{
+	struct dh_ctx *ctx = dh_get_ctx(tfm);
+
+	return mpi_get_size(ctx->p);
+}
+
+static void dh_exit_tfm(struct crypto_kpp *tfm)
+{
+	struct dh_ctx *ctx = dh_get_ctx(tfm);
+
+	dh_free_ctx(ctx);
+}
+
+static struct kpp_alg dh = {
+	.set_secret = dh_set_secret,
+	.generate_public_key = dh_compute_value,
+	.compute_shared_secret = dh_compute_value,
+	.max_size = dh_max_size,
+	.exit = dh_exit_tfm,
+	.base = {
+		.cra_name = "dh",
+		.cra_driver_name = "dh-generic",
+		.cra_priority = 100,
+		.cra_module = THIS_MODULE,
+		.cra_ctxsize = sizeof(struct dh_ctx),
+	},
+};
+
+static int dh_init(void)
+{
+	return crypto_register_kpp(&dh);
+}
+
+static void dh_exit(void)
+{
+	crypto_unregister_kpp(&dh);
+}
+
+module_init(dh_init);
+module_exit(dh_exit);
+MODULE_ALIAS_CRYPTO("dh");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("DH generic algorithm");
diff --git a/crypto/testmgr.c b/crypto/testmgr.c
index c727fb0..d3de362 100644
--- a/crypto/testmgr.c
+++ b/crypto/testmgr.c
@@ -32,6 +32,8 @@
 #include <crypto/rng.h>
 #include <crypto/drbg.h>
 #include <crypto/akcipher.h>
+#include <crypto/kpp.h>
+#include <crypto/dh.h>
 
 #include "internal.h"
 
@@ -120,6 +122,11 @@ struct akcipher_test_suite {
 	unsigned int count;
 };
 
+struct kpp_test_suite {
+	struct kpp_testvec_dh *vecs;
+	unsigned int count;
+};
+
 struct alg_test_desc {
 	const char *alg;
 	int (*test)(const struct alg_test_desc *desc, const char *driver,
@@ -134,6 +141,7 @@ struct alg_test_desc {
 		struct cprng_test_suite cprng;
 		struct drbg_test_suite drbg;
 		struct akcipher_test_suite akcipher;
+		struct kpp_test_suite kpp;
 	} suite;
 };
 
@@ -1777,6 +1785,145 @@ static int alg_test_drbg(const struct alg_test_desc *desc, const char *driver,
 
 }
 
+static int do_test_dh(struct crypto_kpp *tfm, struct kpp_testvec_dh *vec)
+{
+	struct kpp_request *req;
+	void *input_buf = NULL;
+	void *output_buf = NULL;
+	struct tcrypt_result result;
+	unsigned int out_len_max;
+	int err = -ENOMEM;
+	struct scatterlist src, dst;
+	struct dh p;
+
+	req = kpp_request_alloc(tfm, GFP_KERNEL);
+	if (!req)
+		return err;
+
+	init_completion(&result.completion);
+
+	/* Set p,g */
+	p.p = vec->p;
+	p.g = vec->g;
+	p.p_size = vec->p_size;
+	p.g_size = vec->g_size;
+	/* Set A private Key */
+	p.key = vec->xa;
+	p.key_size = vec->xa_size;
+	err = crypto_kpp_set_secret(tfm, (void *)&p);
+	if (err)
+		goto free_req;
+
+	out_len_max = crypto_kpp_maxsize(tfm);
+	output_buf = kzalloc(out_len_max, GFP_KERNEL);
+	if (!output_buf) {
+		err = -ENOMEM;
+		goto free_req;
+	}
+
+	/* Use g as base */
+	kpp_request_set_input(req, NULL, 0);
+	sg_init_one(&dst, output_buf, out_len_max);
+	kpp_request_set_output(req, &dst, out_len_max);
+	kpp_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG,
+				 tcrypt_complete, &result);
+
+	/* Compute A public key = g^xa mod p */
+	err = wait_async_op(&result, crypto_kpp_generate_public_key(req));
+	if (err) {
+		pr_err("alg: dh: generate public key test failed. err %d\n", err);
+		goto free_output;
+	}
+	/* Verify calculated public key */
+	if (memcmp(vec->expected_ya, sg_virt(req->dst), vec->expected_ya_size)) {
+		pr_err("alg: dh: generate public key test failed. Invalid output\n");
+		err = -EINVAL;
+		goto free_output;
+	}
+
+	/* Calculate shared secret key by using counter part public key. */
+	input_buf = kzalloc(vec->yb_size, GFP_KERNEL);
+	if (!input_buf) {
+		err = -ENOMEM;
+		goto free_output;
+	}
+
+	memcpy(input_buf, vec->yb, vec->yb_size);
+	sg_init_one(&src, input_buf, vec->yb_size);
+	sg_init_one(&dst, output_buf, out_len_max);
+	kpp_request_set_input(req, &src, vec->yb_size);
+	kpp_request_set_output(req, &dst, out_len_max);
+	kpp_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG,
+				 tcrypt_complete, &result);
+	err = wait_async_op(&result, crypto_kpp_compute_shared_secret(req));
+	if (err) {
+		pr_err("alg: dh: compute shard secret test failed. err %d\n", err);
+		goto free_all;
+	}
+	/*
+	 * verify shared secret from which the user will derive
+	 * secret key by executing whatever hash it has chosen
+	 */
+	if (memcmp(vec->expected_ss, sg_virt(req->dst),
+		   vec->expected_ss_size)) {
+		pr_err("alg: dh: compute shared secret test failed. Invalid output\n");
+		err = -EINVAL;
+	}
+
+free_all:
+	kfree(input_buf);
+free_output:
+	kfree(output_buf);
+free_req:
+	kpp_request_free(req);
+	return err;
+}
+
+static int test_dh(struct crypto_kpp *tfm, struct kpp_testvec_dh *vecs,
+		   unsigned int tcount)
+{
+	int ret, i;
+
+	for (i = 0; i < tcount; i++) {
+		ret = do_test_dh(tfm, vecs++);
+		if (ret) {
+			pr_err("alg: dh: test failed on vector %d, err=%d\n",
+			       i + 1, ret);
+			return ret;
+		}
+	}
+	return 0;
+}
+
+static int test_kpp(struct crypto_kpp *tfm, const char *alg,
+		    struct kpp_testvec_dh *vecs, unsigned int tcount)
+{
+	if (strncmp(alg, "dh", 2) == 0)
+		return test_dh(tfm, vecs, tcount);
+
+	return 0;
+}
+
+static int alg_test_kpp(const struct alg_test_desc *desc, const char *driver,
+			u32 type, u32 mask)
+{
+	struct crypto_kpp *tfm;
+	int err = 0;
+
+	tfm = crypto_alloc_kpp(driver, type | CRYPTO_ALG_INTERNAL, mask);
+	if (IS_ERR(tfm)) {
+		pr_err("alg: kpp: Failed to load tfm for %s: %ld\n",
+		       driver, PTR_ERR(tfm));
+		return PTR_ERR(tfm);
+	}
+	if (desc->suite.kpp.vecs)
+		err = test_kpp(tfm, desc->alg, desc->suite.kpp.vecs,
+			       desc->suite.kpp.count);
+
+	crypto_free_kpp(tfm);
+	return err;
+}
+
 static int do_test_rsa(struct crypto_akcipher *tfm,
 		       struct akcipher_testvec *vecs)
 {
@@ -2729,6 +2876,16 @@ static const struct alg_test_desc alg_test_descs[] = {
 			}
 		}
 	}, {
+		.alg = "dh",
+		.test = alg_test_kpp,
+		.fips_allowed = 1,
+		.suite = {
+			.kpp = {
+				.vecs = dh_tv_template,
+				.count = DH_TEST_VECTORS
+			}
+		}
+	}, {
 		.alg = "digest_null",
 		.test = alg_test_null,
 	}, {
diff --git a/crypto/testmgr.h b/crypto/testmgr.h
index 487ec88..e9c34c7 100644
--- a/crypto/testmgr.h
+++ b/crypto/testmgr.h
@@ -133,6 +133,21 @@ struct akcipher_testvec {
 	bool public_key_vec;
 };
 
+struct kpp_testvec_dh {
+	unsigned char *p;
+	unsigned char *g;
+	unsigned char *xa;
+	unsigned char *yb;
+	unsigned char *expected_ya;
+	unsigned char *expected_ss;
+	unsigned short p_size;
+	unsigned short g_size;
+	unsigned short xa_size;
+	unsigned short yb_size;
+	unsigned short expected_ya_size;
+	unsigned short expected_ss_size;
+};
+
 static char zeroed_string[48];
 
 /*
@@ -330,6 +345,199 @@ static struct akcipher_testvec rsa_tv_template[] = {
 	}
 };
 
+#define DH_TEST_VECTORS 2
+
+struct kpp_testvec_dh dh_tv_template[] = {
+	{
+	.p =
+	"\xb9\x36\x3a\xf1\x82\x1f\x60\xd3\x22\x47\xb8\xbc\x2d\x22\x6b\x81"
+	"\x7f\xe8\x20\x06\x09\x23\x73\x49\x9a\x59\x8b\x35\x25\xf8\x31\xbc"
+	"\x7d\xa8\x1c\x9d\x56\x0d\x1a\xf7\x4b\x4f\x96\xa4\x35\x77\x6a\x89"
+	"\xab\x42\x00\x49\x21\x71\xed\x28\x16\x1d\x87\x5a\x10\xa7\x9c\x64"
+	"\x94\xd4\x87\x3d\x28\xef\x44\xfe\x4b\xe2\xb4\x15\x8c\x82\xa6\xf3"
+	"\x50\x5f\xa8\xe8\xa2\x60\xe7\x00\x86\x78\x05\xd4\x78\x19\xa1\x98"
+	"\x62\x4e\x4a\x00\x78\x56\x96\xe6\xcf\xd7\x10\x1b\x74\x5d\xd0\x26"
+	"\x61\xdb\x6b\x32\x09\x51\xd8\xa5\xfd\x54\x16\x71\x01\xb3\x39\xe6"
+	"\x4e\x69\xb1\xd7\x06\x8f\xd6\x1e\xdc\x72\x25\x26\x74\xc8\x41\x06"
+	"\x5c\xd1\x26\x5c\xb0\x2f\xf9\x59\x13\xc1\x2a\x0f\x78\xea\x7b\xf7"
+	"\xbd\x59\xa0\x90\x1d\xfc\x33\x5b\x4c\xbf\x05\x9c\x3a\x3f\x69\xa2"
+	"\x45\x61\x4e\x10\x6a\xb3\x17\xc5\x68\x30\xfb\x07\x5f\x34\xc6\xfb"
+	"\x73\x07\x3c\x70\xf6\xae\xe7\x72\x84\xc3\x18\x81\x8f\xe8\x11\x1f"
+	"\x3d\x83\x83\x01\x2a\x14\x73\xbf\x32\x32\x2e\xc9\x4d\xdb\x2a\xca"
+	"\xee\x71\xf9\xda\xad\xe8\x82\x0b\x4d\x0c\x1f\xb6\x1d\xef\x00\x67"
+	"\x74\x3d\x95\xe0\xb7\xc4\x30\x8a\x24\x87\x12\x47\x27\x70\x0d\x73",
+	.g = "\x02",
+	.xa =
+	"\x44\xc1\x48\x36\xa7\x2b\x6f\x4e\x43\x03\x68\xad\x31\x00\xda\xf3"
+	"\x2a\x01\xa8\x32\x63\x5f\x89\x32\x1f\xdf\x4c\xa1\x6a\xbc\x10\x15"
+	"\x90\x35\xc9\x26\x41\xdf\x7b\xaa\x56\x56\x3d\x85\x44\xb5\xc0\x8e"
+	"\x37\x83\x06\x50\xb3\x5f\x0e\x28\x2c\xd5\x46\x15\xe3\xda\x7d\x74"
+	"\x87\x13\x91\x4f\xd4\x2d\xf6\xc7\x5e\x14\x2c\x11\xc2\x26\xb4\x3a"
+	"\xe3\xb2\x36\x20\x11\x3b\x22\xf2\x06\x65\x66\xe2\x57\x58\xf8\x22"
+	"\x1a\x94\xbd\x2b\x0e\x8c\x55\xad\x61\x23\x45\x2b\x19\x1e\x63\x3a"
+	"\x13\x61\xe3\xa0\x79\x70\x3e\x6d\x98\x32\xbc\x7f\x82\xc3\x11\xd8"
+	"\xeb\x53\xb5\xfc\xb5\xd5\x3c\x4a\xea\x92\x3e\x01\xce\x15\x65\xd4"
+	"\xaa\x85\xc1\x11\x90\x83\x31\x6e\xfe\xe7\x7f\x7d\xed\xab\xf9\x29"
+	"\xf8\xc7\xf1\x68\xc6\xb7\xe4\x1f\x2f\x28\xa0\xc9\x1a\x50\x64\x29"
+	"\x4b\x01\x6d\x1a\xda\x46\x63\x21\x07\x40\x8c\x8e\x4c\x6f\xb5\xe5"
+	"\x12\xf3\xc2\x1b\x48\x27\x5e\x27\x01\xb1\xaa\xed\x68\x9b\x83\x18"
+	"\x8f\xb1\xeb\x1f\x04\xd1\x3c\x79\xed\x4b\xf7\x0a\x33\xdc\xe0\xc6"
+	"\xd8\x02\x51\x59\x00\x74\x30\x07\x4c\x2d\xac\xe4\x13\xf1\x80\xf0"
+	"\xce\xfa\xff\xa9\xce\x29\x46\xdd\x9d\xad\xd1\xc3\xc6\x58\x1a\x63",
+	.yb =
+	"\x2a\x67\x5c\xfd\x63\x5d\xc0\x97\x0a\x8b\xa2\x1f\xf8\x8a\xcb\x54"
+	"\xca\x2f\xd3\x49\x3f\x01\x8e\x87\xfe\xcc\x94\xa0\x3e\xd4\x26\x79"
+	"\x9a\x94\x3c\x11\x81\x58\x5c\x60\x3d\xf5\x98\x90\x89\x64\x62\x1f"
+	"\xbd\x05\x6d\x2b\xcd\x84\x40\x9b\x4a\x1f\xe0\x19\xf1\xca\x20\xb3"
+	"\x4e\xa0\x4f\x15\xcc\xa5\xfe\xa5\xb4\xf5\x0b\x18\x7a\x5a\x37\xaa"
+	"\x58\x00\x19\x7f\xe2\xa3\xd9\x1c\x44\x57\xcc\xde\x2e\xc1\x38\xea"
+	"\xeb\xe3\x90\x40\xc4\x6c\xf7\xcd\xe9\x22\x50\x71\xf5\x7c\xdb\x37"
+	"\x0e\x80\xc3\xed\x7e\xb1\x2b\x2f\xbe\x71\xa6\x11\xa5\x9d\xf5\x39"
+	"\xf1\xa2\xe5\x85\xbc\x25\x91\x4e\x84\x8d\x26\x9f\x4f\xe6\x0f\xa6"
+	"\x2b\x6b\xf9\x0d\xaf\x6f\xbb\xfa\x2d\x79\x15\x31\x57\xae\x19\x60"
+	"\x22\x0a\xf5\xfd\x98\x0e\xbf\x5d\x49\x75\x58\x37\xbc\x7f\xf5\x21"
+	"\x56\x1e\xd5\xb3\x50\x0b\xca\x96\xf3\xd1\x3f\xb3\x70\xa8\x6d\x63"
+	"\x48\xfb\x3d\xd7\x29\x91\x45\xb5\x48\xcd\xb6\x78\x30\xf2\x3f\x1e"
+	"\xd6\x22\xd6\x35\x9b\xf9\x1f\x85\xae\xab\x4b\xd7\xe0\xc7\x86\x67"
+	"\x3f\x05\x7f\xa6\x0d\x2f\x0d\xbf\x53\x5f\x4d\x2c\x6d\x5e\x57\x40"
+	"\x30\x3a\x23\x98\xf9\xb4\x32\xf5\x32\x83\xdd\x0b\xae\x33\x97\x2f",
+	.expected_ya =
+	"\x5c\x24\xdf\xeb\x5b\x4b\xf8\xc5\xef\x39\x48\x82\xe0\x1e\x62\xee"
+	"\x8a\xae\xdf\x93\x6c\x2b\x16\x95\x92\x16\x3f\x16\x7b\x75\x03\x85"
+	"\xd9\xf1\x69\xc2\x14\x87\x45\xfc\xa4\x19\xf6\xf0\xa4\xf3\xec\xd4"
+	"\x6c\x5c\x03\x3b\x94\xc2\x2f\x92\xe4\xce\xb3\xe4\x72\xe8\x17\xe6"
+	"\x23\x7e\x00\x01\x09\x59\x13\xbf\xc1\x2f\x99\xa9\x07\xaa\x02\x23"
+	"\x4a\xca\x39\x4f\xbc\xec\x0f\x27\x4f\x19\x93\x6c\xb9\x30\x52\xfd"
+	"\x2b\x9d\x86\xf1\x06\x1e\xb6\x56\x27\x4a\xc9\x8a\xa7\x8a\x48\x5e"
+	"\xb5\x60\xcb\xdf\xff\x03\x26\x10\xbf\x90\x8f\x46\x60\xeb\x9b\x9a"
+	"\xd6\x6f\x44\x91\x03\x92\x18\x2c\x96\x5e\x40\x19\xfb\xf4\x4f\x3a"
+	"\x02\x7b\xaf\xcc\x22\x20\x79\xb9\xf8\x9f\x8f\x85\x6b\xec\x44\xbb"
+	"\xe6\xa8\x8e\xb1\xe8\x2c\xee\x64\xee\xf8\xbd\x00\xf3\xe2\x2b\x93"
+	"\xcd\xe7\xc4\xdf\xc9\x19\x46\xfe\xb6\x07\x73\xc1\x8a\x64\x79\x26"
+	"\xe7\x30\xad\x2a\xdf\xe6\x8f\x59\xf5\x81\xbf\x4a\x29\x91\xe7\xb7"
+	"\xcf\x48\x13\x27\x75\x79\x40\xd9\xd6\x32\x52\x4e\x6a\x86\xae\x6f"
+	"\xc2\xbf\xec\x1f\xc2\x69\xb2\xb6\x59\xe5\xa5\x17\xa4\x77\xb7\x62"
+	"\x46\xde\xe8\xd2\x89\x78\x9a\xef\xa3\xb5\x8f\x26\xec\x80\xda\x39",
+	.expected_ss =
+	"\x8f\xf3\xac\xa2\xea\x22\x11\x5c\x45\x65\x1a\x77\x75\x2e\xcf\x46"
+	"\x23\x14\x1e\x67\x53\x4d\x35\xb0\x38\x1d\x4e\xb9\x41\x9a\x21\x24"
+	"\x6e\x9f\x40\xfe\x90\x51\xb1\x06\xa4\x7b\x87\x17\x2f\xe7\x5e\x22"
+	"\xf0\x7b\x54\x84\x0a\xac\x0a\x90\xd2\xd7\xe8\x7f\xe7\xe3\x30\x75"
+	"\x01\x1f\x24\x75\x56\xbe\xcc\x8d\x1e\x68\x0c\x41\x72\xd3\xfa\xbb"
+	"\xe5\x9c\x60\xc7\x28\x77\x0c\xbe\x89\xab\x08\xd6\x21\xe7\x2e\x1a"
+	"\x58\x7a\xca\x4f\x22\xf3\x2b\x30\xfd\xf4\x98\xc1\xa3\xf8\xf6\xcc"
+	"\xa9\xe4\xdb\x5b\xee\xd5\x5c\x6f\x62\x4c\xd1\x1a\x02\x2a\x23\xe4"
+	"\xb5\x57\xf3\xf9\xec\x04\x83\x54\xfe\x08\x5e\x35\xac\xfb\xa8\x09"
+	"\x82\x32\x60\x11\xb2\x16\x62\x6b\xdf\xda\xde\x9c\xcb\x63\x44\x6c"
+	"\x59\x26\x6a\x8f\xb0\x24\xcb\xa6\x72\x48\x1e\xeb\xe0\xe1\x09\x44"
+	"\xdd\xee\x66\x6d\x84\xcf\xa5\xc1\xb8\x36\x74\xd3\x15\x96\xc3\xe4"
+	"\xc6\x5a\x4d\x23\x97\x0c\x5c\xcb\xa9\xf5\x29\xc2\x0e\xff\x93\x82"
+	"\xd3\x34\x49\xad\x64\xa6\xb1\xc0\x59\x28\x75\x60\xa7\x8a\xb0\x11"
+	"\x56\x89\x42\x74\x11\xf5\xf6\x5e\x6f\x16\x54\x6a\xb1\x76\x4d\x50"
+	"\x8a\x68\xc1\x5b\x82\xb9\x0d\x00\x32\x50\xed\x88\x87\x48\x92\x17",
+	.p_size = 256,
+	.g_size = 1,
+	.xa_size = 256,
+	.yb_size = 256,
+	.expected_ya_size = 256,
+	.expected_ss_size = 256,
+	},
+	{
+	.p =
+	"\xb9\x36\x3a\xf1\x82\x1f\x60\xd3\x22\x47\xb8\xbc\x2d\x22\x6b\x81"
+	"\x7f\xe8\x20\x06\x09\x23\x73\x49\x9a\x59\x8b\x35\x25\xf8\x31\xbc"
+	"\x7d\xa8\x1c\x9d\x56\x0d\x1a\xf7\x4b\x4f\x96\xa4\x35\x77\x6a\x89"
+	"\xab\x42\x00\x49\x21\x71\xed\x28\x16\x1d\x87\x5a\x10\xa7\x9c\x64"
+	"\x94\xd4\x87\x3d\x28\xef\x44\xfe\x4b\xe2\xb4\x15\x8c\x82\xa6\xf3"
+	"\x50\x5f\xa8\xe8\xa2\x60\xe7\x00\x86\x78\x05\xd4\x78\x19\xa1\x98"
+	"\x62\x4e\x4a\x00\x78\x56\x96\xe6\xcf\xd7\x10\x1b\x74\x5d\xd0\x26"
+	"\x61\xdb\x6b\x32\x09\x51\xd8\xa5\xfd\x54\x16\x71\x01\xb3\x39\xe6"
+	"\x4e\x69\xb1\xd7\x06\x8f\xd6\x1e\xdc\x72\x25\x26\x74\xc8\x41\x06"
+	"\x5c\xd1\x26\x5c\xb0\x2f\xf9\x59\x13\xc1\x2a\x0f\x78\xea\x7b\xf7"
+	"\xbd\x59\xa0\x90\x1d\xfc\x33\x5b\x4c\xbf\x05\x9c\x3a\x3f\x69\xa2"
+	"\x45\x61\x4e\x10\x6a\xb3\x17\xc5\x68\x30\xfb\x07\x5f\x34\xc6\xfb"
+	"\x73\x07\x3c\x70\xf6\xae\xe7\x72\x84\xc3\x18\x81\x8f\xe8\x11\x1f"
+	"\x3d\x83\x83\x01\x2a\x14\x73\xbf\x32\x32\x2e\xc9\x4d\xdb\x2a\xca"
+	"\xee\x71\xf9\xda\xad\xe8\x82\x0b\x4d\x0c\x1f\xb6\x1d\xef\x00\x67"
+	"\x74\x3d\x95\xe0\xb7\xc4\x30\x8a\x24\x87\x12\x47\x27\x70\x0d\x73",
+	.g = "\x02",
+	.xa =
+	"\x4d\x75\xa8\x6e\xba\x23\x3a\x0c\x63\x56\xc8\xc9\x5a\xa7\xd6\x0e"
+	"\xed\xae\x40\x78\x87\x47\x5f\xe0\xa7\x7b\xba\x84\x88\x67\x4e\xe5"
+	"\x3c\xcc\x5c\x6a\xe7\x4a\x20\xec\xbe\xcb\xf5\x52\x62\x9f\x37\x80"
+	"\x0c\x72\x7b\x83\x66\xa4\xf6\x7f\x95\x97\x1c\x6a\x5c\x7e\xf1\x67"
+	"\x37\xb3\x93\x39\x3d\x0b\x55\x35\xd9\xe5\x22\x04\x9f\xf8\xc1\x04"
+	"\xce\x13\xa5\xac\xe1\x75\x05\xd1\x2b\x53\xa2\x84\xef\xb1\x18\xf4"
+	"\x66\xdd\xea\xe6\x24\x69\x5a\x49\xe0\x7a\xd8\xdf\x1b\xb7\xf1\x6d"
+	"\x9b\x50\x2c\xc8\x1c\x1c\xa3\xb4\x37\xfb\x66\x3f\x67\x71\x73\xa9"
+	"\xff\x5f\xd9\xa2\x25\x6e\x25\x1b\x26\x54\xbf\x0c\xc6\xdb\xea\x0a"
+	"\x52\x6c\x16\x7c\x27\x68\x15\x71\x58\x73\x9d\xe6\xc2\x80\xaa\x97"
+	"\x31\x66\xfb\xa6\xfb\xfd\xd0\x9c\x1d\xbe\x81\x48\xf5\x9a\x32\xf1"
+	"\x69\x62\x18\x78\xae\x72\x36\xe6\x94\x27\xd1\xff\x18\x4f\x28\x6a"
+	"\x16\xbd\x6a\x60\xee\xe5\xf9\x6d\x16\xe4\xb8\xa6\x41\x9b\x23\x7e"
+	"\xf7\x9d\xd1\x1d\x03\x15\x66\x3a\xcf\xb6\x2c\x13\x96\x2c\x52\x21"
+	"\xe4\x2d\x48\x7a\x8a\x5d\xb2\x88\xed\x98\x61\x79\x8b\x6a\x1e\x5f"
+	"\xd0\x8a\x2d\x99\x5a\x2b\x0f\xbc\xef\x53\x8f\x32\xc1\xa2\x99\x26",
+	.yb =
+	"\x99\x4d\xd9\x01\x84\x8e\x4a\x5b\xb8\xa5\x64\x8c\x6c\x00\x5c\x0e"
+	"\x1e\x1b\xee\x5d\x9f\x53\xe3\x16\x70\x01\xed\xbf\x4f\x14\x36\x6e"
+	"\xe4\x43\x45\x43\x49\xcc\xb1\xb0\x2a\xc0\x6f\x22\x55\x42\x17\x94"
+	"\x18\x83\xd7\x2a\x5c\x51\x54\xf8\x4e\x7c\x10\xda\x76\x68\x57\x77"
+	"\x1e\x62\x03\x30\x04\x7b\x4c\x39\x9c\x54\x01\x54\xec\xef\xb3\x55"
+	"\xa4\xc0\x24\x6d\x3d\xbd\xcc\x46\x5b\x00\x96\xc7\xea\x93\xd1\x3f"
+	"\xf2\x6a\x72\xe3\xf2\xc1\x92\x24\x5b\xda\x48\x70\x2c\xa9\x59\x97"
+	"\x19\xb1\xd6\x54\xb3\x9c\x2e\xb0\x63\x07\x9b\x5e\xac\xb5\xf2\xb1"
+	"\x5b\xf8\xf3\xd7\x2d\x37\x9b\x68\x6c\xf8\x90\x07\xbc\x37\x9a\xa5"
+	"\xe2\x91\x12\x25\x47\x77\xe3\x3d\xb2\x95\x69\x44\x0b\x91\x1e\xaf"
+	"\x7c\x8c\x7c\x34\x41\x6a\xab\x60\x6e\xc6\x52\xec\x7e\x94\x0a\x37"
+	"\xec\x98\x90\xdf\x3f\x02\xbd\x23\x52\xdd\xd9\xe5\x31\x80\x74\x25"
+	"\xb6\xd2\xd3\xcc\xd5\xcc\x6d\xf9\x7e\x4d\x78\xab\x77\x51\xfa\x77"
+	"\x19\x94\x49\x8c\x05\xd4\x75\xed\xd2\xb3\x64\x57\xe0\x52\x99\xc0"
+	"\x83\xe3\xbb\x5e\x2b\xf1\xd2\xc0\xb1\x37\x36\x0b\x7c\xb5\x63\x96"
+	"\x8e\xde\x04\x23\x11\x95\x62\x11\x9a\xce\x6f\x63\xc8\xd5\xd1\x8f",
+	.expected_ya =
+	"\x90\x89\xe4\x82\xd6\x0a\xcf\x1a\xae\xce\x1b\x66\xa7\x19\x71\x18"
+	"\x8f\x95\x4b\x5b\x80\x45\x4a\x5a\x43\x99\x4d\x37\xcf\xa3\xa7\x28"
+	"\x9c\xc7\x73\xf1\xb2\x17\xf6\x99\xe3\x6b\x56\xcb\x3e\x35\x60\x7d"
+	"\x65\xc7\x84\x6b\x3e\x60\xee\xcd\xd2\x70\xe7\xc9\x32\x1c\xf0\xb4"
+	"\xf9\x52\xd9\x88\x75\xfd\x40\x2c\xa7\xbe\x19\x1c\x0a\xae\x93\xe1"
+	"\x71\xc7\xcd\x4f\x33\x5c\x10\x7d\x39\x56\xfc\x73\x84\xb2\x67\xc3"
+	"\x77\x26\x20\x97\x2b\xf8\x13\x43\x93\x9c\x9a\xa4\x08\xc7\x34\x83"
+	"\xe6\x98\x61\xe7\x16\x30\x2c\xb1\xdb\x2a\xb2\xcc\xc3\x02\xa5\x3c"
+	"\x71\x50\x14\x83\xc7\xbb\xa4\xbe\x98\x1b\xfe\xcb\x43\xe9\x97\x62"
+	"\xd6\xf0\x8c\xcb\x1c\xba\x1e\xa8\xa6\xa6\x50\xfc\x85\x7d\x47\xbf"
+	"\xf4\x3e\x23\xd3\x5f\xb2\x71\x3e\x40\x94\xaa\x87\x83\x2c\x6c\x8e"
+	"\x60\xfd\xdd\xf7\xf4\x76\x03\xd3\x1d\xec\x18\x51\xa3\xf2\x44\x1a"
+	"\x3f\xb4\x7c\x18\x0d\x68\x65\x92\x54\x0d\x2d\x81\x16\xf1\x84\x66"
+	"\x89\x92\xd0\x1a\x5e\x1f\x42\x46\x5b\xe5\x83\x86\x80\xd9\xcd\x3a"
+	"\x5a\x2f\xb9\x59\x9b\xe4\x43\x84\x64\xf3\x09\x1a\x0a\xa2\x64\x0f"
+	"\x77\x4e\x8d\x8b\xe6\x88\xd1\xfc\xaf\x8f\xdf\x1d\xbc\x31\xb3\xbd",
+	.expected_ss =
+	"\x34\xc3\x35\x14\x88\x46\x26\x23\x97\xbb\xdd\x28\x5c\x94\xf6\x47"
+	"\xca\xb3\x19\xaf\xca\x44\x9b\xc2\x7d\x89\xfd\x96\x14\xfd\x6d\x58"
+	"\xd8\xc4\x6b\x61\x2a\x0d\xf2\x36\x45\xc8\xe4\xa4\xed\x81\x53\x81"
+	"\x66\x1e\xe0\x5a\xb1\x78\x2d\x0b\x5c\xb4\xd1\xfc\x90\xc6\x9c\xdb"
+	"\x5a\x30\x0b\x14\x7d\xbe\xb3\x7d\xb1\xb2\x76\x3c\x6c\xef\x74\x6b"
+	"\xe7\x1f\x64\x0c\xab\x65\xe1\x76\x5c\x3d\x83\xb5\x8a\xfb\xaf\x0f"
+	"\xf2\x06\x14\x8f\xa0\xf6\xc1\x89\x78\xf2\xba\x72\x73\x3c\xf7\x76"
+	"\x21\x67\xbc\x24\x31\xb8\x09\x65\x0f\x0c\x02\x32\x4a\x98\x14\xfc"
+	"\x72\x2c\x25\x60\x68\x5f\x2f\x30\x1e\x5b\xf0\x3b\xd1\xa2\x87\xa0"
+	"\x54\xdf\xdb\xc0\xee\x0a\x0f\x47\xc9\x90\x20\x2c\xf9\xe3\x52\xad"
+	"\x27\x65\x8d\x54\x8d\xa8\xa1\xf3\xed\x15\xd4\x94\x28\x90\x31\x93"
+	"\x1b\xc0\x51\xbb\x43\x5d\x76\x3b\x1d\x2a\x71\x50\xea\x5d\x48\x94"
+	"\x7f\x6f\xf1\x48\xdb\x30\xe5\xae\x64\x79\xd9\x7a\xdb\xc6\xff\xd8"
+	"\x5e\x5a\x64\xbd\xf6\x85\x04\xe8\x28\x6a\xac\xef\xce\x19\x8e\x9a"
+	"\xfe\x75\xc0\x27\x69\xe3\xb3\x7b\x21\xa7\xb1\x16\xa4\x85\x23\xee"
+	"\xb0\x1b\x04\x6e\xbd\xab\x16\xde\xfd\x86\x6b\xa9\x95\xd7\x0b\xfd",
+	.p_size = 256,
+	.g_size = 1,
+	.xa_size = 256,
+	.yb_size = 256,
+	.expected_ya_size = 256,
+	.expected_ss_size = 256,
+	}
+};
+
 /*
  * MD4 test vectors from RFC1320
  */
diff --git a/include/crypto/dh.h b/include/crypto/dh.h
new file mode 100644
index 0000000..a190ed4
--- /dev/null
+++ b/include/crypto/dh.h
@@ -0,0 +1,25 @@
+/*
+ * Diffie-Hellman params to be used with kpp API
+ *
+ * Copyright (c) 2016, Intel Corporation
+ * Authors: Salvatore Benedetto <salvatore.benedetto@intel.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_DH_
+#define _CRYPTO_DH_
+
+struct dh {
+	void *key;
+	void *p;
+	void *g;
+	unsigned int key_size;
+	unsigned int p_size;
+	unsigned int g_size;
+};
+
+#endif
-- 
2.7.4

^ permalink raw reply related

* [PATCH v8 3/3] crypto: kpp - Add ECDH software support
From: Salvatore Benedetto @ 2016-06-13 21:55 UTC (permalink / raw)
  To: herbert; +Cc: salvatore.benedetto, linux-crypto
In-Reply-To: <1465854948-9084-1-git-send-email-salvatore.benedetto@intel.com>

 * Implement ECDH under kpp API
 * Provide ECC software support for curve P-192 and
   P-256.
 * Add kpp test for ECDH with data generated by OpenSSL

Signed-off-by: Salvatore Benedetto <salvatore.benedetto@intel.com>
---
 crypto/Kconfig          |    5 +
 crypto/Makefile         |    3 +
 crypto/ecc.c            | 1018 +++++++++++++++++++++++++++++++++++++++++++++++
 crypto/ecc.h            |   83 ++++
 crypto/ecc_curve_defs.h |   57 +++
 crypto/ecdh.c           |  151 +++++++
 crypto/testmgr.c        |  135 ++++++-
 crypto/testmgr.h        |   78 ++++
 include/crypto/ecdh.h   |   26 ++
 9 files changed, 1547 insertions(+), 9 deletions(-)
 create mode 100644 crypto/ecc.c
 create mode 100644 crypto/ecc.h
 create mode 100644 crypto/ecc_curve_defs.h
 create mode 100644 crypto/ecdh.c
 create mode 100644 include/crypto/ecdh.h

diff --git a/crypto/Kconfig b/crypto/Kconfig
index 4190e0d..5533c69 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -118,6 +118,11 @@ config CRYPTO_DH
 	help
 	  Generic implementation of the Diffie-Hellman algorithm.
 
+config CRYPTO_ECDH
+	tristate "ECDH algorithm"
+	select CRYTPO_KPP
+	help
+	  Generic implementation of the ECDH algorithm
 
 config CRYPTO_MANAGER
 	tristate "Cryptographic algorithm manager"
diff --git a/crypto/Makefile b/crypto/Makefile
index 101f8fd..ba03079 100644
--- a/crypto/Makefile
+++ b/crypto/Makefile
@@ -33,6 +33,9 @@ obj-$(CONFIG_CRYPTO_AKCIPHER2) += akcipher.o
 obj-$(CONFIG_CRYPTO_KPP2) += kpp.o
 
 obj-$(CONFIG_CRYPTO_DH) += dh.o
+ecdh_generic-y := ecc.o
+ecdh_generic-y += ecdh.o
+obj-$(CONFIG_CRYPTO_ECDH) += ecdh_generic.o
 
 $(obj)/rsapubkey-asn1.o: $(obj)/rsapubkey-asn1.c $(obj)/rsapubkey-asn1.h
 $(obj)/rsaprivkey-asn1.o: $(obj)/rsaprivkey-asn1.c $(obj)/rsaprivkey-asn1.h
diff --git a/crypto/ecc.c b/crypto/ecc.c
new file mode 100644
index 0000000..9aedec6
--- /dev/null
+++ b/crypto/ecc.c
@@ -0,0 +1,1018 @@
+/*
+ * Copyright (c) 2013, Kenneth MacKay
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *  * Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <linux/random.h>
+#include <linux/slab.h>
+#include <linux/swab.h>
+#include <linux/fips.h>
+#include <crypto/ecdh.h>
+
+#include "ecc.h"
+#include "ecc_curve_defs.h"
+
+typedef struct {
+	u64 m_low;
+	u64 m_high;
+} uint128_t;
+
+static inline const struct ecc_curve *ecc_get_curve(unsigned int curve_id)
+{
+	switch (curve_id) {
+	/* In FIPS mode only allow P256 and higher */
+	case ECC_CURVE_NIST_P192:
+		return fips_enabled ? NULL : &nist_p192;
+	case ECC_CURVE_NIST_P256:
+		return &nist_p256;
+	default:
+		return NULL;
+	}
+}
+
+static u64 *ecc_alloc_digits_space(unsigned int ndigits)
+{
+	size_t len = ndigits * sizeof(u64);
+
+	if (!len)
+		return NULL;
+
+	return kmalloc(len, GFP_KERNEL);
+}
+
+static void ecc_free_digits_space(u64 *space)
+{
+	kzfree(space);
+}
+
+static struct ecc_point *ecc_alloc_point(unsigned int ndigits)
+{
+	struct ecc_point *p = kmalloc(sizeof(*p), GFP_KERNEL);
+
+	if (!p)
+		return NULL;
+
+	p->x = ecc_alloc_digits_space(ndigits);
+	if (!p->x)
+		goto err_alloc_x;
+
+	p->y = ecc_alloc_digits_space(ndigits);
+	if (!p->y)
+		goto err_alloc_y;
+
+	p->ndigits = ndigits;
+
+	return p;
+
+err_alloc_y:
+	ecc_free_digits_space(p->x);
+err_alloc_x:
+	kfree(p);
+	return NULL;
+}
+
+static void ecc_free_point(struct ecc_point *p)
+{
+	if (!p)
+		return;
+
+	kzfree(p->x);
+	kzfree(p->y);
+	kzfree(p);
+}
+
+static void vli_clear(u64 *vli, unsigned int ndigits)
+{
+	int i;
+
+	for (i = 0; i < ndigits; i++)
+		vli[i] = 0;
+}
+
+/* Returns true if vli == 0, false otherwise. */
+static bool vli_is_zero(const u64 *vli, unsigned int ndigits)
+{
+	int i;
+
+	for (i = 0; i < ndigits; i++) {
+		if (vli[i])
+			return false;
+	}
+
+	return true;
+}
+
+/* Returns nonzero if bit bit of vli is set. */
+static u64 vli_test_bit(const u64 *vli, unsigned int bit)
+{
+	return (vli[bit / 64] & ((u64)1 << (bit % 64)));
+}
+
+/* Counts the number of 64-bit "digits" in vli. */
+static unsigned int vli_num_digits(const u64 *vli, unsigned int ndigits)
+{
+	int i;
+
+	/* Search from the end until we find a non-zero digit.
+	 * We do it in reverse because we expect that most digits will
+	 * be nonzero.
+	 */
+	for (i = ndigits - 1; i >= 0 && vli[i] == 0; i--);
+
+	return (i + 1);
+}
+
+/* Counts the number of bits required for vli. */
+static unsigned int vli_num_bits(const u64 *vli, unsigned int ndigits)
+{
+	unsigned int i, num_digits;
+	u64 digit;
+
+	num_digits = vli_num_digits(vli, ndigits);
+	if (num_digits == 0)
+		return 0;
+
+	digit = vli[num_digits - 1];
+	for (i = 0; digit; i++)
+		digit >>= 1;
+
+	return ((num_digits - 1) * 64 + i);
+}
+
+/* Sets dest = src. */
+static void vli_set(u64 *dest, const u64 *src, unsigned int ndigits)
+{
+	int i;
+
+	for (i = 0; i < ndigits; i++)
+		dest[i] = src[i];
+}
+
+/* Returns sign of left - right. */
+static int vli_cmp(const u64 *left, const u64 *right, unsigned int ndigits)
+{
+	int i;
+
+	for (i = ndigits - 1; i >= 0; i--) {
+		if (left[i] > right[i])
+			return 1;
+		else if (left[i] < right[i])
+			return -1;
+	}
+
+	return 0;
+}
+
+/* Computes result = in << c, returning carry. Can modify in place
+ * (if result == in). 0 < shift < 64.
+ */
+static u64 vli_lshift(u64 *result, const u64 *in, unsigned int shift,
+		      unsigned int ndigits)
+{
+	u64 carry = 0;
+	int i;
+
+	for (i = 0; i < ndigits; i++) {
+		u64 temp = in[i];
+
+		result[i] = (temp << shift) | carry;
+		carry = temp >> (64 - shift);
+	}
+
+	return carry;
+}
+
+/* Computes vli = vli >> 1. */
+static void vli_rshift1(u64 *vli, unsigned int ndigits)
+{
+	u64 *end = vli;
+	u64 carry = 0;
+
+	vli += ndigits;
+
+	while (vli-- > end) {
+		u64 temp = *vli;
+		*vli = (temp >> 1) | carry;
+		carry = temp << 63;
+	}
+}
+
+/* Computes result = left + right, returning carry. Can modify in place. */
+static u64 vli_add(u64 *result, const u64 *left, const u64 *right,
+		   unsigned int ndigits)
+{
+	u64 carry = 0;
+	int i;
+
+	for (i = 0; i < ndigits; i++) {
+		u64 sum;
+
+		sum = left[i] + right[i] + carry;
+		if (sum != left[i])
+			carry = (sum < left[i]);
+
+		result[i] = sum;
+	}
+
+	return carry;
+}
+
+/* Computes result = left - right, returning borrow. Can modify in place. */
+static u64 vli_sub(u64 *result, const u64 *left, const u64 *right,
+		   unsigned int ndigits)
+{
+	u64 borrow = 0;
+	int i;
+
+	for (i = 0; i < ndigits; i++) {
+		u64 diff;
+
+		diff = left[i] - right[i] - borrow;
+		if (diff != left[i])
+			borrow = (diff > left[i]);
+
+		result[i] = diff;
+	}
+
+	return borrow;
+}
+
+static uint128_t mul_64_64(u64 left, u64 right)
+{
+	u64 a0 = left & 0xffffffffull;
+	u64 a1 = left >> 32;
+	u64 b0 = right & 0xffffffffull;
+	u64 b1 = right >> 32;
+	u64 m0 = a0 * b0;
+	u64 m1 = a0 * b1;
+	u64 m2 = a1 * b0;
+	u64 m3 = a1 * b1;
+	uint128_t result;
+
+	m2 += (m0 >> 32);
+	m2 += m1;
+
+	/* Overflow */
+	if (m2 < m1)
+		m3 += 0x100000000ull;
+
+	result.m_low = (m0 & 0xffffffffull) | (m2 << 32);
+	result.m_high = m3 + (m2 >> 32);
+
+	return result;
+}
+
+static uint128_t add_128_128(uint128_t a, uint128_t b)
+{
+	uint128_t result;
+
+	result.m_low = a.m_low + b.m_low;
+	result.m_high = a.m_high + b.m_high + (result.m_low < a.m_low);
+
+	return result;
+}
+
+static void vli_mult(u64 *result, const u64 *left, const u64 *right,
+		     unsigned int ndigits)
+{
+	uint128_t r01 = { 0, 0 };
+	u64 r2 = 0;
+	unsigned int i, k;
+
+	/* Compute each digit of result in sequence, maintaining the
+	 * carries.
+	 */
+	for (k = 0; k < ndigits * 2 - 1; k++) {
+		unsigned int min;
+
+		if (k < ndigits)
+			min = 0;
+		else
+			min = (k + 1) - ndigits;
+
+		for (i = min; i <= k && i < ndigits; i++) {
+			uint128_t product;
+
+			product = mul_64_64(left[i], right[k - i]);
+
+			r01 = add_128_128(r01, product);
+			r2 += (r01.m_high < product.m_high);
+		}
+
+		result[k] = r01.m_low;
+		r01.m_low = r01.m_high;
+		r01.m_high = r2;
+		r2 = 0;
+	}
+
+	result[ndigits * 2 - 1] = r01.m_low;
+}
+
+static void vli_square(u64 *result, const u64 *left, unsigned int ndigits)
+{
+	uint128_t r01 = { 0, 0 };
+	u64 r2 = 0;
+	int i, k;
+
+	for (k = 0; k < ndigits * 2 - 1; k++) {
+		unsigned int min;
+
+		if (k < ndigits)
+			min = 0;
+		else
+			min = (k + 1) - ndigits;
+
+		for (i = min; i <= k && i <= k - i; i++) {
+			uint128_t product;
+
+			product = mul_64_64(left[i], left[k - i]);
+
+			if (i < k - i) {
+				r2 += product.m_high >> 63;
+				product.m_high = (product.m_high << 1) |
+						 (product.m_low >> 63);
+				product.m_low <<= 1;
+			}
+
+			r01 = add_128_128(r01, product);
+			r2 += (r01.m_high < product.m_high);
+		}
+
+		result[k] = r01.m_low;
+		r01.m_low = r01.m_high;
+		r01.m_high = r2;
+		r2 = 0;
+	}
+
+	result[ndigits * 2 - 1] = r01.m_low;
+}
+
+/* Computes result = (left + right) % mod.
+ * Assumes that left < mod and right < mod, result != mod.
+ */
+static void vli_mod_add(u64 *result, const u64 *left, const u64 *right,
+			const u64 *mod, unsigned int ndigits)
+{
+	u64 carry;
+
+	carry = vli_add(result, left, right, ndigits);
+
+	/* result > mod (result = mod + remainder), so subtract mod to
+	 * get remainder.
+	 */
+	if (carry || vli_cmp(result, mod, ndigits) >= 0)
+		vli_sub(result, result, mod, ndigits);
+}
+
+/* Computes result = (left - right) % mod.
+ * Assumes that left < mod and right < mod, result != mod.
+ */
+static void vli_mod_sub(u64 *result, const u64 *left, const u64 *right,
+			const u64 *mod, unsigned int ndigits)
+{
+	u64 borrow = vli_sub(result, left, right, ndigits);
+
+	/* In this case, p_result == -diff == (max int) - diff.
+	 * Since -x % d == d - x, we can get the correct result from
+	 * result + mod (with overflow).
+	 */
+	if (borrow)
+		vli_add(result, result, mod, ndigits);
+}
+
+/* Computes p_result = p_product % curve_p.
+ * See algorithm 5 and 6 from
+ * http://www.isys.uni-klu.ac.at/PDF/2001-0126-MT.pdf
+ */
+static void vli_mmod_fast_192(u64 *result, const u64 *product,
+			      const u64 *curve_prime, u64 *tmp)
+{
+	const unsigned int ndigits = 3;
+	int carry;
+
+	vli_set(result, product, ndigits);
+
+	vli_set(tmp, &product[3], ndigits);
+	carry = vli_add(result, result, tmp, ndigits);
+
+	tmp[0] = 0;
+	tmp[1] = product[3];
+	tmp[2] = product[4];
+	carry += vli_add(result, result, tmp, ndigits);
+
+	tmp[0] = tmp[1] = product[5];
+	tmp[2] = 0;
+	carry += vli_add(result, result, tmp, ndigits);
+
+	while (carry || vli_cmp(curve_prime, result, ndigits) != 1)
+		carry -= vli_sub(result, result, curve_prime, ndigits);
+}
+
+/* Computes result = product % curve_prime
+ * from http://www.nsa.gov/ia/_files/nist-routines.pdf
+ */
+static void vli_mmod_fast_256(u64 *result, const u64 *product,
+			      const u64 *curve_prime, u64 *tmp)
+{
+	int carry;
+	const unsigned int ndigits = 4;
+
+	/* t */
+	vli_set(result, product, ndigits);
+
+	/* s1 */
+	tmp[0] = 0;
+	tmp[1] = product[5] & 0xffffffff00000000ull;
+	tmp[2] = product[6];
+	tmp[3] = product[7];
+	carry = vli_lshift(tmp, tmp, 1, ndigits);
+	carry += vli_add(result, result, tmp, ndigits);
+
+	/* s2 */
+	tmp[1] = product[6] << 32;
+	tmp[2] = (product[6] >> 32) | (product[7] << 32);
+	tmp[3] = product[7] >> 32;
+	carry += vli_lshift(tmp, tmp, 1, ndigits);
+	carry += vli_add(result, result, tmp, ndigits);
+
+	/* s3 */
+	tmp[0] = product[4];
+	tmp[1] = product[5] & 0xffffffff;
+	tmp[2] = 0;
+	tmp[3] = product[7];
+	carry += vli_add(result, result, tmp, ndigits);
+
+	/* s4 */
+	tmp[0] = (product[4] >> 32) | (product[5] << 32);
+	tmp[1] = (product[5] >> 32) | (product[6] & 0xffffffff00000000ull);
+	tmp[2] = product[7];
+	tmp[3] = (product[6] >> 32) | (product[4] << 32);
+	carry += vli_add(result, result, tmp, ndigits);
+
+	/* d1 */
+	tmp[0] = (product[5] >> 32) | (product[6] << 32);
+	tmp[1] = (product[6] >> 32);
+	tmp[2] = 0;
+	tmp[3] = (product[4] & 0xffffffff) | (product[5] << 32);
+	carry -= vli_sub(result, result, tmp, ndigits);
+
+	/* d2 */
+	tmp[0] = product[6];
+	tmp[1] = product[7];
+	tmp[2] = 0;
+	tmp[3] = (product[4] >> 32) | (product[5] & 0xffffffff00000000ull);
+	carry -= vli_sub(result, result, tmp, ndigits);
+
+	/* d3 */
+	tmp[0] = (product[6] >> 32) | (product[7] << 32);
+	tmp[1] = (product[7] >> 32) | (product[4] << 32);
+	tmp[2] = (product[4] >> 32) | (product[5] << 32);
+	tmp[3] = (product[6] << 32);
+	carry -= vli_sub(result, result, tmp, ndigits);
+
+	/* d4 */
+	tmp[0] = product[7];
+	tmp[1] = product[4] & 0xffffffff00000000ull;
+	tmp[2] = product[5];
+	tmp[3] = product[6] & 0xffffffff00000000ull;
+	carry -= vli_sub(result, result, tmp, ndigits);
+
+	if (carry < 0) {
+		do {
+			carry += vli_add(result, result, curve_prime, ndigits);
+		} while (carry < 0);
+	} else {
+		while (carry || vli_cmp(curve_prime, result, ndigits) != 1)
+			carry -= vli_sub(result, result, curve_prime, ndigits);
+	}
+}
+
+/* Computes result = product % curve_prime
+ *  from http://www.nsa.gov/ia/_files/nist-routines.pdf
+*/
+static bool vli_mmod_fast(u64 *result, u64 *product,
+			  const u64 *curve_prime, unsigned int ndigits)
+{
+	u64 tmp[2 * ndigits];
+
+	switch (ndigits) {
+	case 3:
+		vli_mmod_fast_192(result, product, curve_prime, tmp);
+		break;
+	case 4:
+		vli_mmod_fast_256(result, product, curve_prime, tmp);
+		break;
+	default:
+		pr_err("unsupports digits size!\n");
+		return false;
+	}
+
+	return true;
+}
+
+/* Computes result = (left * right) % curve_prime. */
+static void vli_mod_mult_fast(u64 *result, const u64 *left, const u64 *right,
+			      const u64 *curve_prime, unsigned int ndigits)
+{
+	u64 product[2 * ndigits];
+
+	vli_mult(product, left, right, ndigits);
+	vli_mmod_fast(result, product, curve_prime, ndigits);
+}
+
+/* Computes result = left^2 % curve_prime. */
+static void vli_mod_square_fast(u64 *result, const u64 *left,
+				const u64 *curve_prime, unsigned int ndigits)
+{
+	u64 product[2 * ndigits];
+
+	vli_square(product, left, ndigits);
+	vli_mmod_fast(result, product, curve_prime, ndigits);
+}
+
+#define EVEN(vli) (!(vli[0] & 1))
+/* Computes result = (1 / p_input) % mod. All VLIs are the same size.
+ * See "From Euclid's GCD to Montgomery Multiplication to the Great Divide"
+ * https://labs.oracle.com/techrep/2001/smli_tr-2001-95.pdf
+ */
+static void vli_mod_inv(u64 *result, const u64 *input, const u64 *mod,
+			unsigned int ndigits)
+{
+	u64 a[ndigits], b[ndigits];
+	u64 u[ndigits], v[ndigits];
+	u64 carry;
+	int cmp_result;
+
+	if (vli_is_zero(input, ndigits)) {
+		vli_clear(result, ndigits);
+		return;
+	}
+
+	vli_set(a, input, ndigits);
+	vli_set(b, mod, ndigits);
+	vli_clear(u, ndigits);
+	u[0] = 1;
+	vli_clear(v, ndigits);
+
+	while ((cmp_result = vli_cmp(a, b, ndigits)) != 0) {
+		carry = 0;
+
+		if (EVEN(a)) {
+			vli_rshift1(a, ndigits);
+
+			if (!EVEN(u))
+				carry = vli_add(u, u, mod, ndigits);
+
+			vli_rshift1(u, ndigits);
+			if (carry)
+				u[ndigits - 1] |= 0x8000000000000000ull;
+		} else if (EVEN(b)) {
+			vli_rshift1(b, ndigits);
+
+			if (!EVEN(v))
+				carry = vli_add(v, v, mod, ndigits);
+
+			vli_rshift1(v, ndigits);
+			if (carry)
+				v[ndigits - 1] |= 0x8000000000000000ull;
+		} else if (cmp_result > 0) {
+			vli_sub(a, a, b, ndigits);
+			vli_rshift1(a, ndigits);
+
+			if (vli_cmp(u, v, ndigits) < 0)
+				vli_add(u, u, mod, ndigits);
+
+			vli_sub(u, u, v, ndigits);
+			if (!EVEN(u))
+				carry = vli_add(u, u, mod, ndigits);
+
+			vli_rshift1(u, ndigits);
+			if (carry)
+				u[ndigits - 1] |= 0x8000000000000000ull;
+		} else {
+			vli_sub(b, b, a, ndigits);
+			vli_rshift1(b, ndigits);
+
+			if (vli_cmp(v, u, ndigits) < 0)
+				vli_add(v, v, mod, ndigits);
+
+			vli_sub(v, v, u, ndigits);
+			if (!EVEN(v))
+				carry = vli_add(v, v, mod, ndigits);
+
+			vli_rshift1(v, ndigits);
+			if (carry)
+				v[ndigits - 1] |= 0x8000000000000000ull;
+		}
+	}
+
+	vli_set(result, u, ndigits);
+}
+
+/* ------ Point operations ------ */
+
+/* Returns true if p_point is the point at infinity, false otherwise. */
+static bool ecc_point_is_zero(const struct ecc_point *point)
+{
+	return (vli_is_zero(point->x, point->ndigits) &&
+		vli_is_zero(point->y, point->ndigits));
+}
+
+/* Point multiplication algorithm using Montgomery's ladder with co-Z
+ * coordinates. From http://eprint.iacr.org/2011/338.pdf
+ */
+
+/* Double in place */
+static void ecc_point_double_jacobian(u64 *x1, u64 *y1, u64 *z1,
+				      u64 *curve_prime, unsigned int ndigits)
+{
+	/* t1 = x, t2 = y, t3 = z */
+	u64 t4[ndigits];
+	u64 t5[ndigits];
+
+	if (vli_is_zero(z1, ndigits))
+		return;
+
+	/* t4 = y1^2 */
+	vli_mod_square_fast(t4, y1, curve_prime, ndigits);
+	/* t5 = x1*y1^2 = A */
+	vli_mod_mult_fast(t5, x1, t4, curve_prime, ndigits);
+	/* t4 = y1^4 */
+	vli_mod_square_fast(t4, t4, curve_prime, ndigits);
+	/* t2 = y1*z1 = z3 */
+	vli_mod_mult_fast(y1, y1, z1, curve_prime, ndigits);
+	/* t3 = z1^2 */
+	vli_mod_square_fast(z1, z1, curve_prime, ndigits);
+
+	/* t1 = x1 + z1^2 */
+	vli_mod_add(x1, x1, z1, curve_prime, ndigits);
+	/* t3 = 2*z1^2 */
+	vli_mod_add(z1, z1, z1, curve_prime, ndigits);
+	/* t3 = x1 - z1^2 */
+	vli_mod_sub(z1, x1, z1, curve_prime, ndigits);
+	/* t1 = x1^2 - z1^4 */
+	vli_mod_mult_fast(x1, x1, z1, curve_prime, ndigits);
+
+	/* t3 = 2*(x1^2 - z1^4) */
+	vli_mod_add(z1, x1, x1, curve_prime, ndigits);
+	/* t1 = 3*(x1^2 - z1^4) */
+	vli_mod_add(x1, x1, z1, curve_prime, ndigits);
+	if (vli_test_bit(x1, 0)) {
+		u64 carry = vli_add(x1, x1, curve_prime, ndigits);
+
+		vli_rshift1(x1, ndigits);
+		x1[ndigits - 1] |= carry << 63;
+	} else {
+		vli_rshift1(x1, ndigits);
+	}
+	/* t1 = 3/2*(x1^2 - z1^4) = B */
+
+	/* t3 = B^2 */
+	vli_mod_square_fast(z1, x1, curve_prime, ndigits);
+	/* t3 = B^2 - A */
+	vli_mod_sub(z1, z1, t5, curve_prime, ndigits);
+	/* t3 = B^2 - 2A = x3 */
+	vli_mod_sub(z1, z1, t5, curve_prime, ndigits);
+	/* t5 = A - x3 */
+	vli_mod_sub(t5, t5, z1, curve_prime, ndigits);
+	/* t1 = B * (A - x3) */
+	vli_mod_mult_fast(x1, x1, t5, curve_prime, ndigits);
+	/* t4 = B * (A - x3) - y1^4 = y3 */
+	vli_mod_sub(t4, x1, t4, curve_prime, ndigits);
+
+	vli_set(x1, z1, ndigits);
+	vli_set(z1, y1, ndigits);
+	vli_set(y1, t4, ndigits);
+}
+
+/* Modify (x1, y1) => (x1 * z^2, y1 * z^3) */
+static void apply_z(u64 *x1, u64 *y1, u64 *z, u64 *curve_prime,
+		    unsigned int ndigits)
+{
+	u64 t1[ndigits];
+
+	vli_mod_square_fast(t1, z, curve_prime, ndigits);    /* z^2 */
+	vli_mod_mult_fast(x1, x1, t1, curve_prime, ndigits); /* x1 * z^2 */
+	vli_mod_mult_fast(t1, t1, z, curve_prime, ndigits);  /* z^3 */
+	vli_mod_mult_fast(y1, y1, t1, curve_prime, ndigits); /* y1 * z^3 */
+}
+
+/* P = (x1, y1) => 2P, (x2, y2) => P' */
+static void xycz_initial_double(u64 *x1, u64 *y1, u64 *x2, u64 *y2,
+				u64 *p_initial_z, u64 *curve_prime,
+				unsigned int ndigits)
+{
+	u64 z[ndigits];
+
+	vli_set(x2, x1, ndigits);
+	vli_set(y2, y1, ndigits);
+
+	vli_clear(z, ndigits);
+	z[0] = 1;
+
+	if (p_initial_z)
+		vli_set(z, p_initial_z, ndigits);
+
+	apply_z(x1, y1, z, curve_prime, ndigits);
+
+	ecc_point_double_jacobian(x1, y1, z, curve_prime, ndigits);
+
+	apply_z(x2, y2, z, curve_prime, ndigits);
+}
+
+/* Input P = (x1, y1, Z), Q = (x2, y2, Z)
+ * Output P' = (x1', y1', Z3), P + Q = (x3, y3, Z3)
+ * or P => P', Q => P + Q
+ */
+static void xycz_add(u64 *x1, u64 *y1, u64 *x2, u64 *y2, u64 *curve_prime,
+		     unsigned int ndigits)
+{
+	/* t1 = X1, t2 = Y1, t3 = X2, t4 = Y2 */
+	u64 t5[ndigits];
+
+	/* t5 = x2 - x1 */
+	vli_mod_sub(t5, x2, x1, curve_prime, ndigits);
+	/* t5 = (x2 - x1)^2 = A */
+	vli_mod_square_fast(t5, t5, curve_prime, ndigits);
+	/* t1 = x1*A = B */
+	vli_mod_mult_fast(x1, x1, t5, curve_prime, ndigits);
+	/* t3 = x2*A = C */
+	vli_mod_mult_fast(x2, x2, t5, curve_prime, ndigits);
+	/* t4 = y2 - y1 */
+	vli_mod_sub(y2, y2, y1, curve_prime, ndigits);
+	/* t5 = (y2 - y1)^2 = D */
+	vli_mod_square_fast(t5, y2, curve_prime, ndigits);
+
+	/* t5 = D - B */
+	vli_mod_sub(t5, t5, x1, curve_prime, ndigits);
+	/* t5 = D - B - C = x3 */
+	vli_mod_sub(t5, t5, x2, curve_prime, ndigits);
+	/* t3 = C - B */
+	vli_mod_sub(x2, x2, x1, curve_prime, ndigits);
+	/* t2 = y1*(C - B) */
+	vli_mod_mult_fast(y1, y1, x2, curve_prime, ndigits);
+	/* t3 = B - x3 */
+	vli_mod_sub(x2, x1, t5, curve_prime, ndigits);
+	/* t4 = (y2 - y1)*(B - x3) */
+	vli_mod_mult_fast(y2, y2, x2, curve_prime, ndigits);
+	/* t4 = y3 */
+	vli_mod_sub(y2, y2, y1, curve_prime, ndigits);
+
+	vli_set(x2, t5, ndigits);
+}
+
+/* Input P = (x1, y1, Z), Q = (x2, y2, Z)
+ * Output P + Q = (x3, y3, Z3), P - Q = (x3', y3', Z3)
+ * or P => P - Q, Q => P + Q
+ */
+static void xycz_add_c(u64 *x1, u64 *y1, u64 *x2, u64 *y2, u64 *curve_prime,
+		       unsigned int ndigits)
+{
+	/* t1 = X1, t2 = Y1, t3 = X2, t4 = Y2 */
+	u64 t5[ndigits];
+	u64 t6[ndigits];
+	u64 t7[ndigits];
+
+	/* t5 = x2 - x1 */
+	vli_mod_sub(t5, x2, x1, curve_prime, ndigits);
+	/* t5 = (x2 - x1)^2 = A */
+	vli_mod_square_fast(t5, t5, curve_prime, ndigits);
+	/* t1 = x1*A = B */
+	vli_mod_mult_fast(x1, x1, t5, curve_prime, ndigits);
+	/* t3 = x2*A = C */
+	vli_mod_mult_fast(x2, x2, t5, curve_prime, ndigits);
+	/* t4 = y2 + y1 */
+	vli_mod_add(t5, y2, y1, curve_prime, ndigits);
+	/* t4 = y2 - y1 */
+	vli_mod_sub(y2, y2, y1, curve_prime, ndigits);
+
+	/* t6 = C - B */
+	vli_mod_sub(t6, x2, x1, curve_prime, ndigits);
+	/* t2 = y1 * (C - B) */
+	vli_mod_mult_fast(y1, y1, t6, curve_prime, ndigits);
+	/* t6 = B + C */
+	vli_mod_add(t6, x1, x2, curve_prime, ndigits);
+	/* t3 = (y2 - y1)^2 */
+	vli_mod_square_fast(x2, y2, curve_prime, ndigits);
+	/* t3 = x3 */
+	vli_mod_sub(x2, x2, t6, curve_prime, ndigits);
+
+	/* t7 = B - x3 */
+	vli_mod_sub(t7, x1, x2, curve_prime, ndigits);
+	/* t4 = (y2 - y1)*(B - x3) */
+	vli_mod_mult_fast(y2, y2, t7, curve_prime, ndigits);
+	/* t4 = y3 */
+	vli_mod_sub(y2, y2, y1, curve_prime, ndigits);
+
+	/* t7 = (y2 + y1)^2 = F */
+	vli_mod_square_fast(t7, t5, curve_prime, ndigits);
+	/* t7 = x3' */
+	vli_mod_sub(t7, t7, t6, curve_prime, ndigits);
+	/* t6 = x3' - B */
+	vli_mod_sub(t6, t7, x1, curve_prime, ndigits);
+	/* t6 = (y2 + y1)*(x3' - B) */
+	vli_mod_mult_fast(t6, t6, t5, curve_prime, ndigits);
+	/* t2 = y3' */
+	vli_mod_sub(y1, t6, y1, curve_prime, ndigits);
+
+	vli_set(x1, t7, ndigits);
+}
+
+static void ecc_point_mult(struct ecc_point *result,
+			   const struct ecc_point *point, const u64 *scalar,
+			   u64 *initial_z, u64 *curve_prime,
+			   unsigned int ndigits)
+{
+	/* R0 and R1 */
+	u64 rx[2][ndigits];
+	u64 ry[2][ndigits];
+	u64 z[ndigits];
+	int i, nb;
+	int num_bits = vli_num_bits(scalar, ndigits);
+
+	vli_set(rx[1], point->x, ndigits);
+	vli_set(ry[1], point->y, ndigits);
+
+	xycz_initial_double(rx[1], ry[1], rx[0], ry[0], initial_z, curve_prime,
+			    ndigits);
+
+	for (i = num_bits - 2; i > 0; i--) {
+		nb = !vli_test_bit(scalar, i);
+		xycz_add_c(rx[1 - nb], ry[1 - nb], rx[nb], ry[nb], curve_prime,
+			   ndigits);
+		xycz_add(rx[nb], ry[nb], rx[1 - nb], ry[1 - nb], curve_prime,
+			 ndigits);
+	}
+
+	nb = !vli_test_bit(scalar, 0);
+	xycz_add_c(rx[1 - nb], ry[1 - nb], rx[nb], ry[nb], curve_prime,
+		   ndigits);
+
+	/* Find final 1/Z value. */
+	/* X1 - X0 */
+	vli_mod_sub(z, rx[1], rx[0], curve_prime, ndigits);
+	/* Yb * (X1 - X0) */
+	vli_mod_mult_fast(z, z, ry[1 - nb], curve_prime, ndigits);
+	/* xP * Yb * (X1 - X0) */
+	vli_mod_mult_fast(z, z, point->x, curve_prime, ndigits);
+
+	/* 1 / (xP * Yb * (X1 - X0)) */
+	vli_mod_inv(z, z, curve_prime, point->ndigits);
+
+	/* yP / (xP * Yb * (X1 - X0)) */
+	vli_mod_mult_fast(z, z, point->y, curve_prime, ndigits);
+	/* Xb * yP / (xP * Yb * (X1 - X0)) */
+	vli_mod_mult_fast(z, z, rx[1 - nb], curve_prime, ndigits);
+	/* End 1/Z calculation */
+
+	xycz_add(rx[nb], ry[nb], rx[1 - nb], ry[1 - nb], curve_prime, ndigits);
+
+	apply_z(rx[0], ry[0], z, curve_prime, ndigits);
+
+	vli_set(result->x, rx[0], ndigits);
+	vli_set(result->y, ry[0], ndigits);
+}
+
+static inline void ecc_swap_digits(const u64 *in, u64 *out,
+				   unsigned int ndigits)
+{
+	int i;
+
+	for (i = 0; i < ndigits; i++)
+		out[i] = __swab64(in[ndigits - 1 - i]);
+}
+
+int ecc_is_key_valid(unsigned int curve_id, unsigned int ndigits,
+		     const u8 *private_key, unsigned int private_key_len)
+{
+	int nbytes;
+	const struct ecc_curve *curve = ecc_get_curve(curve_id);
+
+	if (!private_key)
+		return -EINVAL;
+
+	nbytes = ndigits << ECC_DIGITS_TO_BYTES_SHIFT;
+
+	if (private_key_len != nbytes)
+		return -EINVAL;
+
+	if (vli_is_zero((const u64 *)&private_key[0], ndigits))
+		return -EINVAL;
+
+	/* Make sure the private key is in the range [1, n-1]. */
+	if (vli_cmp(curve->n, (const u64 *)&private_key[0], ndigits) != 1)
+		return -EINVAL;
+
+	return 0;
+}
+
+int ecdh_make_pub_key(unsigned int curve_id, unsigned int ndigits,
+		      const u8 *private_key, unsigned int private_key_len,
+		      u8 *public_key, unsigned int public_key_len)
+{
+	int ret = 0;
+	struct ecc_point *pk;
+	u64 priv[ndigits];
+	unsigned int nbytes;
+	const struct ecc_curve *curve = ecc_get_curve(curve_id);
+
+	if (!private_key || !curve) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	ecc_swap_digits((const u64 *)private_key, priv, ndigits);
+
+	pk = ecc_alloc_point(ndigits);
+	if (!pk) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	ecc_point_mult(pk, &curve->g, priv, NULL, curve->p, ndigits);
+	if (ecc_point_is_zero(pk)) {
+		ret = -EAGAIN;
+		goto err_free_point;
+	}
+
+	nbytes = ndigits << ECC_DIGITS_TO_BYTES_SHIFT;
+	ecc_swap_digits(pk->x, (u64 *)public_key, ndigits);
+	ecc_swap_digits(pk->y, (u64 *)&public_key[nbytes], ndigits);
+
+err_free_point:
+	ecc_free_point(pk);
+out:
+	return ret;
+}
+
+int ecdh_shared_secret(unsigned int curve_id, unsigned int ndigits,
+		       const u8 *private_key, unsigned int private_key_len,
+		       const u8 *public_key, unsigned int public_key_len,
+		       u8 *secret, unsigned int secret_len)
+{
+	int ret = 0;
+	struct ecc_point *product, *pk;
+	u64 priv[ndigits];
+	u64 rand_z[ndigits];
+	unsigned int nbytes;
+	const struct ecc_curve *curve = ecc_get_curve(curve_id);
+
+	if (!private_key || !public_key || !curve) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	nbytes = ndigits << ECC_DIGITS_TO_BYTES_SHIFT;
+
+	get_random_bytes(rand_z, nbytes);
+
+	pk = ecc_alloc_point(ndigits);
+	if (!pk) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	product = ecc_alloc_point(ndigits);
+	if (!product) {
+		ret = -ENOMEM;
+		goto err_alloc_product;
+	}
+
+	ecc_swap_digits((const u64 *)public_key, pk->x, ndigits);
+	ecc_swap_digits((const u64 *)&public_key[nbytes], pk->y, ndigits);
+	ecc_swap_digits((const u64 *)private_key, priv, ndigits);
+
+	ecc_point_mult(product, pk, priv, rand_z, curve->p, ndigits);
+
+	ecc_swap_digits(product->x, (u64 *)secret, ndigits);
+
+	if (ecc_point_is_zero(product))
+		ret = -EFAULT;
+
+	ecc_free_point(product);
+err_alloc_product:
+	ecc_free_point(pk);
+out:
+	return ret;
+}
diff --git a/crypto/ecc.h b/crypto/ecc.h
new file mode 100644
index 0000000..b5db4b9
--- /dev/null
+++ b/crypto/ecc.h
@@ -0,0 +1,83 @@
+/*
+ * Copyright (c) 2013, Kenneth MacKay
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *  * Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+#ifndef _CRYPTO_ECC_H
+#define _CRYPTO_ECC_H
+
+#define ECC_MAX_DIGITS	4 /* 256 */
+
+#define ECC_DIGITS_TO_BYTES_SHIFT 3
+
+/**
+ * ecc_is_key_valid() - Validate a given ECDH private key
+ *
+ * @curve_id:		id representing the curve to use
+ * @ndigits:		curve number of digits
+ * @private_key:	private key to be used for the given curve
+ * @private_key_len:	private key len
+ *
+ * Returns 0 if the key is acceptable, a negative value otherwise
+ */
+int ecc_is_key_valid(unsigned int curve_id, unsigned int ndigits,
+		     const u8 *private_key, unsigned int private_key_len);
+
+/**
+ * ecdh_make_pub_key() - Compute an ECC public key
+ *
+ * @curve_id:		id representing the curve to use
+ * @private_key:	pregenerated private key for the given curve
+ * @private_key_len:	length of private_key
+ * @public_key:		buffer for storing the public key generated
+ * @public_key_len:	length of the public_key buffer
+ *
+ * Returns 0 if the public key was generated successfully, a negative value
+ * if an error occurred.
+ */
+int ecdh_make_pub_key(const unsigned int curve_id, unsigned int ndigits,
+		      const u8 *private_key, unsigned int private_key_len,
+		      u8 *public_key, unsigned int public_key_len);
+
+/**
+ * ecdh_shared_secret() - Compute a shared secret
+ *
+ * @curve_id:		id representing the curve to use
+ * @private_key:	private key of part A
+ * @private_key_len:	length of private_key
+ * @public_key:		public key of counterpart B
+ * @public_key_len:	length of public_key
+ * @secret:		buffer for storing the calculated shared secret
+ * @secret_len:		length of the secret buffer
+ *
+ * Note: It is recommended that you hash the result of ecdh_shared_secret
+ * before using it for symmetric encryption or HMAC.
+ *
+ * Returns 0 if the shared secret was generated successfully, a negative value
+ * if an error occurred.
+ */
+int ecdh_shared_secret(unsigned int curve_id, unsigned int ndigits,
+		       const u8 *private_key, unsigned int private_key_len,
+		       const u8 *public_key, unsigned int public_key_len,
+		       u8 *secret, unsigned int secret_len);
+#endif
diff --git a/crypto/ecc_curve_defs.h b/crypto/ecc_curve_defs.h
new file mode 100644
index 0000000..03ae5f7
--- /dev/null
+++ b/crypto/ecc_curve_defs.h
@@ -0,0 +1,57 @@
+#ifndef _CRYTO_ECC_CURVE_DEFS_H
+#define _CRYTO_ECC_CURVE_DEFS_H
+
+struct ecc_point {
+	u64 *x;
+	u64 *y;
+	u8 ndigits;
+};
+
+struct ecc_curve {
+	char *name;
+	struct ecc_point g;
+	u64 *p;
+	u64 *n;
+};
+
+/* NIST P-192 */
+static u64 nist_p192_g_x[] = { 0xF4FF0AFD82FF1012ull, 0x7CBF20EB43A18800ull,
+				0x188DA80EB03090F6ull };
+static u64 nist_p192_g_y[] = { 0x73F977A11E794811ull, 0x631011ED6B24CDD5ull,
+				0x07192B95FFC8DA78ull };
+static u64 nist_p192_p[] = { 0xFFFFFFFFFFFFFFFFull, 0xFFFFFFFFFFFFFFFEull,
+				0xFFFFFFFFFFFFFFFFull };
+static u64 nist_p192_n[] = { 0x146BC9B1B4D22831ull, 0xFFFFFFFF99DEF836ull,
+				0xFFFFFFFFFFFFFFFFull };
+static struct ecc_curve nist_p192 = {
+	.name = "nist_192",
+	.g = {
+		.x = nist_p192_g_x,
+		.y = nist_p192_g_y,
+		.ndigits = 3,
+	},
+	.p = nist_p192_p,
+	.n = nist_p192_n
+};
+
+/* NIST P-256 */
+static u64 nist_p256_g_x[] = { 0xF4A13945D898C296ull, 0x77037D812DEB33A0ull,
+				0xF8BCE6E563A440F2ull, 0x6B17D1F2E12C4247ull };
+static u64 nist_p256_g_y[] = { 0xCBB6406837BF51F5ull, 0x2BCE33576B315ECEull,
+				0x8EE7EB4A7C0F9E16ull, 0x4FE342E2FE1A7F9Bull };
+static u64 nist_p256_p[] = { 0xFFFFFFFFFFFFFFFFull, 0x00000000FFFFFFFFull,
+				0x0000000000000000ull, 0xFFFFFFFF00000001ull };
+static u64 nist_p256_n[] = { 0xF3B9CAC2FC632551ull, 0xBCE6FAADA7179E84ull,
+				0xFFFFFFFFFFFFFFFFull, 0xFFFFFFFF00000000ull };
+static struct ecc_curve nist_p256 = {
+	.name = "nist_256",
+	.g = {
+		.x = nist_p256_g_x,
+		.y = nist_p256_g_y,
+		.ndigits = 4,
+	},
+	.p = nist_p256_p,
+	.n = nist_p256_n
+};
+
+#endif
diff --git a/crypto/ecdh.c b/crypto/ecdh.c
new file mode 100644
index 0000000..640b425
--- /dev/null
+++ b/crypto/ecdh.c
@@ -0,0 +1,151 @@
+/* ECDH key-agreement protocol
+ *
+ * Copyright (c) 2016, Intel Corporation
+ * Authors: Salvator Benedetto <salvatore.benedetto@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <crypto/internal/kpp.h>
+#include <crypto/kpp.h>
+#include <crypto/ecdh.h>
+#include <linux/scatterlist.h>
+#include "ecc.h"
+
+struct ecdh_ctx {
+	unsigned int curve_id;
+	unsigned int ndigits;
+	u64 private_key[ECC_MAX_DIGITS];
+	u64 public_key[2 * ECC_MAX_DIGITS];
+	u64 shared_secret[ECC_MAX_DIGITS];
+};
+
+static inline struct ecdh_ctx *ecdh_get_ctx(struct crypto_kpp *tfm)
+{
+	return kpp_tfm_ctx(tfm);
+}
+
+static unsigned int ecdh_supported_curve(unsigned int curve_id)
+{
+	switch (curve_id) {
+	case ECC_CURVE_NIST_P192: return 3;
+	case ECC_CURVE_NIST_P256: return 4;
+	default: return 0;
+	}
+}
+
+static int ecdh_set_secret(struct crypto_kpp *tfm, void *buffer)
+{
+	struct ecdh_ctx *ctx = ecdh_get_ctx(tfm);
+	struct ecdh *params = (struct ecdh *)buffer;
+	unsigned int ndigits;
+
+	if (unlikely(!buffer))
+		return -EINVAL;
+
+	ndigits = ecdh_supported_curve(params->curve_id);
+	if (!ndigits)
+		return -EINVAL;
+
+	ctx->curve_id = params->curve_id;
+	ctx->ndigits = ndigits;
+
+	if (ecc_is_key_valid(ctx->curve_id, ctx->ndigits,
+			     (const u8 *)params->key, params->key_size) < 0)
+		return -EINVAL;
+
+	memcpy(ctx->private_key, params->key, params->key_size);
+
+	return 0;
+}
+
+static int ecdh_compute_value(struct kpp_request *req)
+{
+	int ret = 0;
+	struct crypto_kpp *tfm = crypto_kpp_reqtfm(req);
+	struct ecdh_ctx *ctx = ecdh_get_ctx(tfm);
+	size_t copied, nbytes;
+	void *buf;
+
+	nbytes = ctx->ndigits << ECC_DIGITS_TO_BYTES_SHIFT;
+
+	if (req->src) {
+		copied = sg_copy_to_buffer(req->src, 1, ctx->public_key,
+					   2 * nbytes);
+		if (copied != 2 * nbytes)
+			return -EINVAL;
+
+		ret = ecdh_shared_secret(ctx->curve_id, ctx->ndigits,
+					 (const u8 *)ctx->private_key, nbytes,
+					 (const u8 *)ctx->public_key, 2 * nbytes,
+					 (u8 *)ctx->shared_secret, nbytes);
+
+		buf = ctx->shared_secret;
+	} else {
+		ret = ecdh_make_pub_key(ctx->curve_id, ctx->ndigits,
+					(const u8 *)ctx->private_key, nbytes,
+					(u8 *)ctx->public_key,
+					sizeof(ctx->public_key));
+		buf = ctx->public_key;
+		/* Public part is a point thus it has both coordinates */
+		nbytes *= 2;
+	}
+
+	if (ret < 0)
+		return ret;
+
+	copied = sg_copy_from_buffer(req->dst, 1, buf, nbytes);
+	if (copied != nbytes)
+		return -EINVAL;
+
+	return ret;
+}
+
+static int ecdh_max_size(struct crypto_kpp *tfm)
+{
+	struct ecdh_ctx *ctx = ecdh_get_ctx(tfm);
+	int nbytes = ctx->ndigits << ECC_DIGITS_TO_BYTES_SHIFT;
+
+	/* Public key is made of two coordinates */
+	return 2 * nbytes;
+}
+
+static void no_exit_tfm(struct crypto_kpp *tfm)
+{
+	return;
+}
+
+static struct kpp_alg ecdh = {
+	.set_secret = ecdh_set_secret,
+	.generate_public_key = ecdh_compute_value,
+	.compute_shared_secret = ecdh_compute_value,
+	.max_size = ecdh_max_size,
+	.exit = no_exit_tfm,
+	.base = {
+		.cra_name = "ecdh",
+		.cra_driver_name = "ecdh-generic",
+		.cra_priority = 100,
+		.cra_module = THIS_MODULE,
+		.cra_ctxsize = sizeof(struct ecdh_ctx),
+	},
+};
+
+static int ecdh_init(void)
+{
+	return crypto_register_kpp(&ecdh);
+}
+
+static void ecdh_exit(void)
+{
+	crypto_unregister_kpp(&ecdh);
+}
+
+module_init(ecdh_init);
+module_exit(ecdh_exit);
+MODULE_ALIAS_CRYPTO("ecdh");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("ECDH generic algorithm");
diff --git a/crypto/testmgr.c b/crypto/testmgr.c
index d3de362..af7ce75 100644
--- a/crypto/testmgr.c
+++ b/crypto/testmgr.c
@@ -34,6 +34,7 @@
 #include <crypto/akcipher.h>
 #include <crypto/kpp.h>
 #include <crypto/dh.h>
+#include <crypto/ecdh.h>
 
 #include "internal.h"
 
@@ -123,7 +124,10 @@ struct akcipher_test_suite {
 };
 
 struct kpp_test_suite {
-	struct kpp_testvec_dh *vecs;
+	union {
+		struct kpp_testvec_dh *dh;
+		struct kpp_testvec_ecdh *ecdh;
+	} vecs;
 	unsigned int count;
 };
 
@@ -1895,12 +1899,112 @@ static int test_dh(struct crypto_kpp *tfm, struct kpp_testvec_dh *vecs,
 	return 0;
 }
 
-static int test_kpp(struct crypto_kpp *tfm, const char *alg,
-		    struct kpp_testvec_dh *vecs, unsigned int tcount)
+static int do_test_ecdh(struct crypto_kpp *tfm, struct kpp_testvec_ecdh *vec)
+{
+	struct kpp_request *req;
+	void *input_buf = NULL;
+	void *output_buf = NULL;
+	struct tcrypt_result result;
+	unsigned int out_len_max;
+	int err = -ENOMEM;
+	struct scatterlist src, dst;
+	struct ecdh p;
+	unsigned int nbytes = vec->ndigits << ECC_DIGITS_TO_BYTES_SHIFT;
+
+	req = kpp_request_alloc(tfm, GFP_KERNEL);
+	if (!req)
+		return err;
+
+	init_completion(&result.completion);
+
+	/* Set curve_id */
+	p.curve_id = vec->curve_id;
+	/* Set A private Key */
+	p.key = vec->private_a;
+	p.key_size = nbytes;
+	err = crypto_kpp_set_secret(tfm, (void *)&p);
+	if (err)
+		goto free_req;
+
+	out_len_max = crypto_kpp_maxsize(tfm);
+	output_buf = kzalloc(out_len_max, GFP_KERNEL);
+	if (!output_buf) {
+		err = -ENOMEM;
+		goto free_req;
+	}
+
+	kpp_request_set_input(req, NULL, 0);
+	sg_init_one(&dst, output_buf, out_len_max);
+	kpp_request_set_output(req, &dst, out_len_max);
+	kpp_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG,
+				 tcrypt_complete, &result);
+
+	/* Compute A public key = aG mod p */
+	err = wait_async_op(&result, crypto_kpp_generate_public_key(req));
+	if (err) {
+		pr_err("alg: ecdh: generate public key test failed. err %d\n",
+		       err);
+		goto free_output;
+	}
+	/* Verify calculated public key */
+	if (memcmp(vec->expected_pub_a, sg_virt(req->dst), 2 * nbytes)) {
+		pr_err("alg: ecdh: generate public key test failed. Invalid output\n");
+		err = -EINVAL;
+		goto free_output;
+	}
+
+	/* Calculate shared secret key by using counter part public key. */
+	input_buf = kzalloc(2 * nbytes, GFP_KERNEL);
+	if (!input_buf) {
+		err = -ENOMEM;
+		goto free_output;
+	}
+
+	memcpy(input_buf, vec->public_b, 2 * nbytes);
+	sg_init_one(&src, input_buf, 2 * nbytes);
+	sg_init_one(&dst, output_buf, out_len_max);
+	kpp_request_set_input(req, &src, 2 * nbytes);
+	kpp_request_set_output(req, &dst, out_len_max);
+	kpp_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG,
+				 tcrypt_complete, &result);
+	err = wait_async_op(&result, crypto_kpp_compute_shared_secret(req));
+	if (err) {
+		pr_err("alg: ecdh: compute shard secret test failed. err %d\n",
+		       err);
+		goto free_all;
+	}
+
+	/*
+	 * verify shared secret from which the user will derive
+	 * secret key by executing whatever hash it has chosen
+	 */
+	if (memcmp(vec->expected_ss, sg_virt(req->dst), nbytes)) {
+		pr_err("alg: ecdh: compute shared secret test failed. Invalid output\n");
+		err = -EINVAL;
+	}
+
+free_all:
+	kfree(input_buf);
+free_output:
+	kfree(output_buf);
+free_req:
+	kpp_request_free(req);
+	return err;
+}
+
+static int test_ecdh(struct crypto_kpp *tfm, struct kpp_testvec_ecdh *vecs,
+		     unsigned int tcount)
 {
-	if (strncmp(alg, "dh", 2) == 0)
-		return test_dh(tfm, vecs, tcount);
+	int ret, i;
 
+	for (i = 0; i < tcount; i++) {
+		ret = do_test_ecdh(tfm, vecs++);
+		if (ret) {
+			pr_err("alg: ecdh: test failed on vector %d, err=%d\n",
+			       i + 1, ret);
+			return ret;
+		}
+	}
 	return 0;
 }
 
@@ -1916,9 +2020,12 @@ static int alg_test_kpp(const struct alg_test_desc *desc, const char *driver,
 		       driver, PTR_ERR(tfm));
 		return PTR_ERR(tfm);
 	}
-	if (desc->suite.kpp.vecs)
-		err = test_kpp(tfm, desc->alg, desc->suite.kpp.vecs,
-			       desc->suite.kpp.count);
+	if (!strncmp(desc->alg, "dh", 2) && desc->suite.kpp.vecs.dh)
+		err = test_dh(tfm, desc->suite.kpp.vecs.dh,
+			      desc->suite.kpp.count);
+	else if (!strncmp(desc->alg, "ecdh", 4) && desc->suite.kpp.vecs.ecdh)
+		err = test_ecdh(tfm, desc->suite.kpp.vecs.ecdh,
+				desc->suite.kpp.count);
 
 	crypto_free_kpp(tfm);
 	return err;
@@ -2881,7 +2988,7 @@ static const struct alg_test_desc alg_test_descs[] = {
 		.fips_allowed = 1,
 		.suite = {
 			.kpp = {
-				.vecs = dh_tv_template,
+				.vecs.dh = dh_tv_template,
 				.count = DH_TEST_VECTORS
 			}
 		}
@@ -3314,6 +3421,16 @@ static const struct alg_test_desc alg_test_descs[] = {
 			}
 		}
 	}, {
+		.alg = "ecdh",
+		.test = alg_test_kpp,
+		.fips_allowed = 1,
+		.suite = {
+			.kpp = {
+				.vecs.ecdh = ecdh_tv_template,
+				.count = ECDH_TEST_VECTORS
+			}
+		}
+	}, {
 		.alg = "gcm(aes)",
 		.test = alg_test_aead,
 		.fips_allowed = 1,
diff --git a/crypto/testmgr.h b/crypto/testmgr.h
index e9c34c7..d2cbb54 100644
--- a/crypto/testmgr.h
+++ b/crypto/testmgr.h
@@ -26,6 +26,8 @@
 
 #include <linux/netlink.h>
 
+#include "ecc.h"
+
 #define MAX_DIGEST_SIZE		64
 #define MAX_TAP			8
 
@@ -148,6 +150,15 @@ struct kpp_testvec_dh {
 	unsigned short expected_ss_size;
 };
 
+struct kpp_testvec_ecdh {
+	unsigned int curve_id;
+	char *private_a;
+	char *expected_pub_a;
+	char *public_b;
+	char *expected_ss;
+	unsigned short ndigits;
+};
+
 static char zeroed_string[48];
 
 /*
@@ -538,6 +549,73 @@ struct kpp_testvec_dh dh_tv_template[] = {
 	}
 };
 
+#ifdef CONFIG_CRYPTO_FIPS
+#define ECDH_TEST_VECTORS 1
+#else
+#define ECDH_TEST_VECTORS 2
+#endif
+struct kpp_testvec_ecdh ecdh_tv_template[] = {
+	{
+#ifndef CONFIG_CRYPTO_FIPS
+	.curve_id = ECC_CURVE_NIST_P192,
+	.private_a =
+	"\xb5\x05\xb1\x71\x1e\xbf\x8c\xda"
+	"\x4e\x19\x1e\x62\x1f\x23\x23\x31"
+	"\x36\x1e\xd3\x84\x2f\xcc\x21\x72",
+	.expected_pub_a =
+	"\x1a\x04\xdb\xa5\xe1\xdd\x4e\x79"
+	"\xa3\xe6\xef\x0e\x5c\x80\x49\x85"
+	"\xfa\x78\xb4\xef\x49\xbd\x4c\x7c"
+	"\x22\x90\x21\x02\xf9\x1b\x81\x5d"
+	"\x0c\x8a\xa8\x98\xd6\x27\x69\x88"
+	"\x5e\xbc\x94\xd8\x15\x9e\x21\xce",
+	.public_b =
+	"\xc3\xba\x67\x4b\x71\xec\xd0\x76"
+	"\x7a\x99\x75\x64\x36\x13\x9a\x94"
+	"\x5d\x8b\xdc\x60\x90\x91\xfd\x3f"
+	"\xb0\x1f\x8a\x0a\x68\xc6\x88\x6e"
+	"\x83\x87\xdd\x67\x09\xf8\x8d\x96"
+	"\x07\xd6\xbd\x1c\xe6\x8d\x9d\x67",
+	.expected_ss =
+	"\xf4\x57\xcc\x4f\x1f\x4e\x31\xcc"
+	"\xe3\x40\x60\xc8\x06\x93\xc6\x2e"
+	"\x99\x80\x81\x28\xaf\xc5\x51\x74",
+	.ndigits = 3,
+	}, {
+#endif
+	.curve_id = ECC_CURVE_NIST_P256,
+	.private_a =
+	"\x24\xd1\x21\xeb\xe5\xcf\x2d\x83"
+	"\xf6\x62\x1b\x6e\x43\x84\x3a\xa3"
+	"\x8b\xe0\x86\xc3\x20\x19\xda\x92"
+	"\x50\x53\x03\xe1\xc0\xea\xb8\x82",
+	.expected_pub_a =
+	"\x1a\x7f\xeb\x52\x00\xbd\x3c\x31"
+	"\x7d\xb6\x70\xc1\x86\xa6\xc7\xc4"
+	"\x3b\xc5\x5f\x6c\x6f\x58\x3c\xf5"
+	"\xb6\x63\x82\x77\x33\x24\xa1\x5f"
+	"\x6a\xca\x43\x6f\xf7\x7e\xff\x02"
+	"\x37\x08\xcc\x40\x5e\x7a\xfd\x6a"
+	"\x6a\x02\x6e\x41\x87\x68\x38\x77"
+	"\xfa\xa9\x44\x43\x2d\xef\x09\xdf",
+	.public_b =
+	"\xcc\xb4\xda\x74\xb1\x47\x3f\xea"
+	"\x6c\x70\x9e\x38\x2d\xc7\xaa\xb7"
+	"\x29\xb2\x47\x03\x19\xab\xdd\x34"
+	"\xbd\xa8\x2c\x93\xe1\xa4\x74\xd9"
+	"\x64\x63\xf7\x70\x20\x2f\xa4\xe6"
+	"\x9f\x4a\x38\xcc\xc0\x2c\x49\x2f"
+	"\xb1\x32\xbb\xaf\x22\x61\xda\xcb"
+	"\x6f\xdb\xa9\xaa\xfc\x77\x81\xf3",
+	.expected_ss =
+	"\xea\x17\x6f\x7e\x6e\x57\x26\x38"
+	"\x8b\xfb\x41\xeb\xba\xc8\x6d\xa5"
+	"\xa8\x72\xd1\xff\xc9\x47\x3d\xaa"
+	"\x58\x43\x9f\x34\x0f\x8c\xf3\xc9",
+	.ndigits = 4,
+	}
+};
+
 /*
  * MD4 test vectors from RFC1320
  */
diff --git a/include/crypto/ecdh.h b/include/crypto/ecdh.h
new file mode 100644
index 0000000..af33dca
--- /dev/null
+++ b/include/crypto/ecdh.h
@@ -0,0 +1,26 @@
+/*
+ * ECDH params to be used with kpp API
+ *
+ * Copyright (c) 2016, Intel Corporation
+ * Authors: Salvatore Benedetto <salvatore.benedetto@intel.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_ECDH_
+#define _CRYPTO_ECDH_
+
+/* Curves IDs */
+#define ECC_CURVE_NIST_P192	0x0001
+#define ECC_CURVE_NIST_P256	0x0002
+
+struct ecdh {
+	unsigned int curve_id;
+	char *key;
+	unsigned short key_size;
+};
+
+#endif
-- 
2.7.4

^ permalink raw reply related

* Re: [PATCH v2 3/3] ARM64: dts: meson-gxbb: Add Hardware Random Generator node
From: Kevin Hilman @ 2016-06-13 22:09 UTC (permalink / raw)
  To: Neil Armstrong
  Cc: Matt Mackall, Herbert Xu, devicetree, linux-kernel, linux-crypto,
	linux-amlogic, linux-arm-kernel
In-Reply-To: <1465546915-24229-4-git-send-email-narmstrong@baylibre.com>

Hi Neil,

Neil Armstrong <narmstrong@baylibre.com> writes:

> Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
> ---
>  arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi | 5 +++++
>  1 file changed, 5 insertions(+)
>
> diff --git a/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi b/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi
> index 832815d..8353621 100644
> --- a/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi
> +++ b/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi
> @@ -167,6 +167,11 @@
>  			};
>  		};
>  
> +		rng {
> +			compatible = "amlogic,meson-rng";
> +			reg = <0x0 0xc8834000 0x0 0x4>;
> +		};

This should be under the periphs bus, with an offset of 0x0 instead of
at the top level.

See the for-next branch in the linux-amlogic tree[1] which has separate
busses for periphs and hiu.

Kevin

[1] git://git.kernel.org/pub/scm/linux/kernel/git/khilman/linux-amlogic.git

^ permalink raw reply

* Re: [PATCH v2 0/3] hw_random: Add Amlogic Meson SoCs Random Generator driver
From: Kevin Hilman @ 2016-06-13 22:10 UTC (permalink / raw)
  To: Herbert Xu
  Cc: Neil Armstrong, linux-crypto, linux-amlogic, linux-kernel,
	linux-arm-kernel, Matt Mackall
In-Reply-To: <20160613123109.GA8674@gondor.apana.org.au>

Hi Herbert,

Herbert Xu <herbert@gondor.apana.org.au> writes:

> On Fri, Jun 10, 2016 at 10:21:52AM +0200, Neil Armstrong wrote:
>> Add support for the Amlogic Meson SoCs Hardware Random generator as a hw_random char driver.
>> The generator is a single 32bit wide register.
>> Also adds the Meson GXBB SoC DTSI node and corresponding DT bindings.
>> 
>> Changes since v1 at http://lkml.kernel.org/r/1464943621-18278-1-git-send-email-narmstrong@baylibre.com :
>> - change to depend on ARCH_MESON || COMPILE_TEST
>> - check buffer max size in read
>> 
>> Neil Armstrong (3):
>>   char: hw_random: Add Amlogic Meson Hardware Random Generator
>>   dt-bindings: hwrng: Add Amlogic Meson Hardware Random Generator
>>     bindings
>>   ARM64: dts: meson-gxbb: Add Hardware Random Generator node
>
> All applied.  Thanks.

Could you take just the driver please?

Due to lots of other activity in the DT, I'd prefer to send the DT &
bindings though the arm-soc (via the amlogic tree.)

Thanks,

Kevin

^ permalink raw reply

* Re: [PATCH v6 3/6] crypto: AF_ALG -- add asymmetric cipher interface
From: Andrew Zaborowski @ 2016-06-13 22:16 UTC (permalink / raw)
  To: Mat Martineau
  Cc: Stephan Mueller, Tadeusz Struk, David Howells, Herbert Xu,
	linux-api, marcel, linux-kernel, keyrings,
	Linux Crypto Mailing List, David Woodhouse, davem
In-Reply-To: <alpine.OSX.2.20.1606081135160.16651@mjmartin-mac01.local>

Hi,

On 8 June 2016 at 21:14, Mat Martineau
<mathew.j.martineau@linux.intel.com> wrote:
> On Wed, 8 Jun 2016, Stephan Mueller wrote:
>> What is your concern?
> Userspace must allocate larger buffers than it knows are necessary for
> expected results.
>
> It looks like the software rsa implementation handles shorter output buffers
> ok (mpi_write_to_sgl will return EOVERFLOW if the the buffer is too small),
> however I see at least one hardware rsa driver that requires the output
> buffer to be the maximum size. But this inconsistency might be best
> addressed within the software cipher or drivers rather than in recvmsg.

Should the hardware drivers fix this instead?  I've looked at the qat
and caam drivers, they both require the destination buffer size to be
the key size and in both cases there would be no penalty for dropping
this requirement as far as I see.  Both do a memmove if the result
ends up being shorter than key size.  In case the caller knows it is
expecting a specific output size, the driver will have to use a self
allocated buffer + a memcpy in those same cases where it would later
use memmove instead.  Alternatively the sg passed to dma_map_sg can be
prepended with a dummy segment the right size to save the memcpy.

akcipher.h only says:
@dst_len: Size of the output buffer. It needs to be at least as big as
the expected result depending on the operation

Note that for random input data the memmove will be done about 1 in
256 times but with PKCS#1 padding the signature always has a leading
zero.

Requiring buffers bigger than needed makes the added work of dropping
the zero bytes from the sglist and potentially re-adding them in the
client difficult to justify.  RSA doing this sets a precedent for a
future pkcs1pad (or other algorithm) implementation to do the same
thing and a portable client having to always know the key size and use
key-sized buffers.

Best regards

^ permalink raw reply

* Re: [PATCH] crypto : async implementation for sha1-mb
From: Herbert Xu @ 2016-06-14  4:34 UTC (permalink / raw)
  To: Dey, Megha
  Cc: tim.c.chen@linux.intel.com, davem@davemloft.net,
	linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org,
	Yu, Fenghua, Megha Dey
In-Reply-To: <C440BA31B54DCD4AAC682D2365C8FEE703CABA2C@ORSMSX111.amr.corp.intel.com>

On Mon, Jun 13, 2016 at 07:10:26PM +0000, Dey, Megha wrote:
>
> > In the current implementation, the inner algorithm is called directly, and we use the outer algorithm's callback. We do not use the callback in inner algorithm. We are actually calling the child functions directly and the child is using the parent's call back function. Probably I can add a comment before the set callback function.. will this be ok?

No this is a hack and you should not do that.

You can of course set the inner request's callback to that of the outer request.

Cheers,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt

^ permalink raw reply

* Re: [PATCH v2 3/3] ARM64: dts: meson-gxbb: Add Hardware Random Generator node
From: Neil Armstrong @ 2016-06-14  4:59 UTC (permalink / raw)
  To: Kevin Hilman
  Cc: Matt Mackall, Herbert Xu, devicetree, linux-kernel, linux-crypto,
	linux-amlogic, linux-arm-kernel
In-Reply-To: <m2ziqoviz0.fsf@baylibre.com>

On 06/14/2016 12:09 AM, Kevin Hilman wrote:
> Hi Neil,
> 
> Neil Armstrong <narmstrong@baylibre.com> writes:
> 
>> Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
>> ---
>>  arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi | 5 +++++
>>  1 file changed, 5 insertions(+)
>>
>> diff --git a/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi b/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi
>> index 832815d..8353621 100644
>> --- a/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi
>> +++ b/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi
>> @@ -167,6 +167,11 @@
>>  			};
>>  		};
>>  
>> +		rng {
>> +			compatible = "amlogic,meson-rng";
>> +			reg = <0x0 0xc8834000 0x0 0x4>;
>> +		};
> 
> This should be under the periphs bus, with an offset of 0x0 instead of
> at the top level.
> 
> See the for-next branch in the linux-amlogic tree[1] which has separate
> busses for periphs and hiu.

Yes, It was introduced lately.

Herbert,

I'll repost this patch separately to arm-soc directly rebased on [1].

Thanks,
Neil

> Kevin
> 
> [1] git://git.kernel.org/pub/scm/linux/kernel/git/khilman/linux-amlogic.git
> 

^ permalink raw reply

* Re: [PATCH v6 3/6] crypto: AF_ALG -- add asymmetric cipher interface
From: Stephan Mueller @ 2016-06-14  5:12 UTC (permalink / raw)
  To: Andrew Zaborowski
  Cc: Mat Martineau, Tadeusz Struk, David Howells, Herbert Xu,
	linux-api, marcel, linux-kernel, keyrings,
	Linux Crypto Mailing List, David Woodhouse, davem
In-Reply-To: <CAOq732J6J9b0NWuELRs7udiO7mApybfxjFaYX_UVdqHR+9Fvrw@mail.gmail.com>

Am Dienstag, 14. Juni 2016, 00:16:11 schrieb Andrew Zaborowski:

Hi Andrew,

> Hi,
> 
> On 8 June 2016 at 21:14, Mat Martineau
> 
> <mathew.j.martineau@linux.intel.com> wrote:
> > On Wed, 8 Jun 2016, Stephan Mueller wrote:
> >> What is your concern?
> > 
> > Userspace must allocate larger buffers than it knows are necessary for
> > expected results.
> > 
> > It looks like the software rsa implementation handles shorter output
> > buffers ok (mpi_write_to_sgl will return EOVERFLOW if the the buffer is
> > too small), however I see at least one hardware rsa driver that requires
> > the output buffer to be the maximum size. But this inconsistency might be
> > best addressed within the software cipher or drivers rather than in
> > recvmsg.
> Should the hardware drivers fix this instead?  I've looked at the qat
> and caam drivers, they both require the destination buffer size to be
> the key size and in both cases there would be no penalty for dropping
> this requirement as far as I see.  Both do a memmove if the result
> ends up being shorter than key size.  In case the caller knows it is
> expecting a specific output size, the driver will have to use a self
> allocated buffer + a memcpy in those same cases where it would later
> use memmove instead.  Alternatively the sg passed to dma_map_sg can be
> prepended with a dummy segment the right size to save the memcpy.
> 
> akcipher.h only says:
> @dst_len: Size of the output buffer. It needs to be at least as big as
> the expected result depending on the operation
> 
> Note that for random input data the memmove will be done about 1 in
> 256 times but with PKCS#1 padding the signature always has a leading
> zero.
> 
> Requiring buffers bigger than needed makes the added work of dropping
> the zero bytes from the sglist and potentially re-adding them in the
> client difficult to justify.  RSA doing this sets a precedent for a
> future pkcs1pad (or other algorithm) implementation to do the same
> thing and a portable client having to always know the key size and use
> key-sized buffers.

I think we have agreed on dropping the length enforcement at the interface 
level.

Ciao
Stephan

^ permalink raw reply

* [PATCH v2 0/4] crypto: CTR DRBG - performance improvements
From: Stephan Mueller @ 2016-06-14  5:33 UTC (permalink / raw)
  To: herbert, linux-crypto

Hi,

The following patch set is aimed to increase the performance of the CTR
DRBG, especially when assembler implementations of the CTR AES mode are
available.

The patch set increases the performance by 10% for random numbers of 16 bytes
and reaches 450% for random numbers reaching 4096 bytes (larger random
numbers will even have more performance gains). The performance gains were
measured when using ctr-aes-aesni.

Note, when using the C implementation of the CTR mode (cipher/ctr.c), the
performance of the CTR DRBG is slightly worse than it is now, but still it
is much faster than the Hash or HMAC DRBGs.

The patch set is CAVS tested.

Changes v2:
* the alignment patch is updated to use the alignment of the underlying TFM

Stephan Mueller (4):
  crypto: CTR DRBG - use CTR AES instead of ECB AES
  crypto: DRBG - use aligned buffers
  crypto: CTR DRBG - use full CTR AES for update
  crypto: CTR DRBG - avoid duplicate maintenance of key

 crypto/Kconfig        |   1 +
 crypto/drbg.c         | 252 +++++++++++++++++++++++++++++++++-----------------
 include/crypto/drbg.h |  12 +++
 3 files changed, 181 insertions(+), 84 deletions(-)

-- 
2.5.5

^ permalink raw reply

* [PATCH v2 1/4] crypto: CTR DRBG - use CTR AES instead of ECB AES
From: Stephan Mueller @ 2016-06-14  5:34 UTC (permalink / raw)
  To: herbert; +Cc: linux-crypto
In-Reply-To: <1842774.dgV8IOeQEu@positron.chronox.de>

The CTR DRBG derives its random data from the CTR that is encrypted with
AES.

This patch now changes the CTR DRBG implementation such that the
CTR AES mode is employed. This allows the use of steamlined CTR AES
implementation such as ctr-aes-aesni.

Unfortunately there are the following subtile changes we need to apply
when using the CTR AES mode:

- the CTR mode increments the counter after the cipher operation, but
  the CTR DRBG requires the increment before the cipher op. Hence, the
  crypto_inc is applied to the counter (drbg->V) once it is
  recalculated.

- the CTR mode wants to encrypt data, but the CTR DRBG is interested in
  the encrypted counter only. The full CTR mode is the XOR of the
  encrypted counter with the plaintext data. To access the encrypted
  counter, the patch uses a NULL data vector as plaintext to be
  "encrypted".

Signed-off-by: Stephan Mueller <smueller@chronox.de>
---
 crypto/Kconfig        |   1 +
 crypto/drbg.c         | 193 ++++++++++++++++++++++++++++++++++++--------------
 include/crypto/drbg.h |   9 +++
 3 files changed, 149 insertions(+), 54 deletions(-)

diff --git a/crypto/Kconfig b/crypto/Kconfig
index 1d33beb..c903f18 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -1567,6 +1567,7 @@ config CRYPTO_DRBG_HASH
 config CRYPTO_DRBG_CTR
 	bool "Enable CTR DRBG"
 	select CRYPTO_AES
+	depends on CRYPTO_CTR
 	help
 	  Enable the CTR DRBG variant as defined in NIST SP800-90A.
 
diff --git a/crypto/drbg.c b/crypto/drbg.c
index 0aca2b9..4ee1a9c 100644
--- a/crypto/drbg.c
+++ b/crypto/drbg.c
@@ -258,6 +258,7 @@ static int drbg_kcapi_sym(struct drbg_state *drbg, unsigned char *outval,
 			  const struct drbg_string *in);
 static int drbg_init_sym_kernel(struct drbg_state *drbg);
 static int drbg_fini_sym_kernel(struct drbg_state *drbg);
+static int drbg_kcapi_sym_ctr(struct drbg_state *drbg, u8 *outbuf, u32 outlen);
 
 /* BCC function for CTR DRBG as defined in 10.4.3 */
 static int drbg_ctr_bcc(struct drbg_state *drbg,
@@ -482,36 +483,37 @@ static int drbg_ctr_update(struct drbg_state *drbg, struct list_head *seed,
 				 drbg_blocklen(drbg);
 	unsigned char *temp_p, *df_data_p; /* pointer to iterate over buffers */
 	unsigned int len = 0;
-	struct drbg_string cipherin;
 
 	if (3 > reseed)
 		memset(df_data, 0, drbg_statelen(drbg));
 
-	/* 10.2.1.3.2 step 2 and 10.2.1.4.2 step 2 */
-	if (seed) {
-		ret = drbg_ctr_df(drbg, df_data, drbg_statelen(drbg), seed);
+	if (!reseed) {
+		/*
+		 * The DRBG uses the CTR mode of the underlying AES cipher. The
+		 * CTR mode increments the counter value after the AES operation
+		 * but SP800-90A requires that the counter is incremented before
+		 * the AES operation. Hence, we increment it at the time we set
+		 * it by one.
+		 */
+		crypto_inc(drbg->V, drbg_blocklen(drbg));
+
+		ret = crypto_skcipher_setkey(drbg->ctr_handle, drbg->C,
+					     drbg_keylen(drbg));
 		if (ret)
 			goto out;
-		drbg_kcapi_symsetkey(drbg, drbg->C);
 	}
 
-	drbg_string_fill(&cipherin, drbg->V, drbg_blocklen(drbg));
-	/*
-	 * 10.2.1.3.2 steps 2 and 3 are already covered as the allocation
-	 * zeroizes all memory during initialization
-	 */
-	while (len < (drbg_statelen(drbg))) {
-		/* 10.2.1.2 step 2.1 */
-		crypto_inc(drbg->V, drbg_blocklen(drbg));
-		/*
-		 * 10.2.1.2 step 2.2 */
-		ret = drbg_kcapi_sym(drbg, temp + len, &cipherin);
+	/* 10.2.1.3.2 step 2 and 10.2.1.4.2 step 2 */
+	if (seed) {
+		ret = drbg_ctr_df(drbg, df_data, drbg_statelen(drbg), seed);
 		if (ret)
 			goto out;
-		/* 10.2.1.2 step 2.3 and 3 */
-		len += drbg_blocklen(drbg);
 	}
 
+	ret = drbg_kcapi_sym_ctr(drbg, temp, drbg_statelen(drbg));
+	if (ret)
+		return ret;
+
 	/* 10.2.1.2 step 4 */
 	temp_p = temp;
 	df_data_p = df_data;
@@ -522,9 +524,14 @@ static int drbg_ctr_update(struct drbg_state *drbg, struct list_head *seed,
 
 	/* 10.2.1.2 step 5 */
 	memcpy(drbg->C, temp, drbg_keylen(drbg));
-	drbg_kcapi_symsetkey(drbg, drbg->C);
+	ret = crypto_skcipher_setkey(drbg->ctr_handle, drbg->C,
+				     drbg_keylen(drbg));
+	if (ret)
+		goto out;
 	/* 10.2.1.2 step 6 */
 	memcpy(drbg->V, temp + drbg_keylen(drbg), drbg_blocklen(drbg));
+	/* See above: increment counter by one to compensate timing of CTR op */
+	crypto_inc(drbg->V, drbg_blocklen(drbg));
 	ret = 0;
 
 out:
@@ -543,46 +550,26 @@ static int drbg_ctr_generate(struct drbg_state *drbg,
 			     unsigned char *buf, unsigned int buflen,
 			     struct list_head *addtl)
 {
-	int len = 0;
-	int ret = 0;
-	struct drbg_string data;
+	int ret;
+	int len = min_t(int, buflen, INT_MAX);
 
 	/* 10.2.1.5.2 step 2 */
 	if (addtl && !list_empty(addtl)) {
 		ret = drbg_ctr_update(drbg, addtl, 2);
 		if (ret)
 			return 0;
-		drbg_kcapi_symsetkey(drbg, drbg->C);
 	}
 
 	/* 10.2.1.5.2 step 4.1 */
-	crypto_inc(drbg->V, drbg_blocklen(drbg));
-	drbg_string_fill(&data, drbg->V, drbg_blocklen(drbg));
-	while (len < buflen) {
-		int outlen = 0;
-		/* 10.2.1.5.2 step 4.2 */
-		ret = drbg_kcapi_sym(drbg, drbg->scratchpad, &data);
-		if (ret) {
-			len = ret;
-			goto out;
-		}
-		outlen = (drbg_blocklen(drbg) < (buflen - len)) ?
-			  drbg_blocklen(drbg) : (buflen - len);
-		/* 10.2.1.5.2 step 4.3 */
-		memcpy(buf + len, drbg->scratchpad, outlen);
-		len += outlen;
-		/* 10.2.1.5.2 step 6 */
-		if (len < buflen)
-			crypto_inc(drbg->V, drbg_blocklen(drbg));
-	}
+	ret = drbg_kcapi_sym_ctr(drbg, buf, len);
+	if (ret)
+		return ret;
 
 	/* 10.2.1.5.2 step 6 */
 	ret = drbg_ctr_update(drbg, NULL, 3);
 	if (ret)
 		len = ret;
 
-out:
-	memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
 	return len;
 }
 
@@ -1634,10 +1621,46 @@ static int drbg_kcapi_hash(struct drbg_state *drbg, unsigned char *outval,
 #endif /* (CONFIG_CRYPTO_DRBG_HASH || CONFIG_CRYPTO_DRBG_HMAC) */
 
 #ifdef CONFIG_CRYPTO_DRBG_CTR
+static int drbg_fini_sym_kernel(struct drbg_state *drbg)
+{
+	struct crypto_cipher *tfm =
+		(struct crypto_cipher *)drbg->priv_data;
+	if (tfm)
+		crypto_free_cipher(tfm);
+	drbg->priv_data = NULL;
+
+	if (drbg->ctr_handle)
+		crypto_free_skcipher(drbg->ctr_handle);
+	drbg->ctr_handle = NULL;
+
+	if (drbg->ctr_req)
+		skcipher_request_free(drbg->ctr_req);;
+	drbg->ctr_req = NULL;
+
+	kfree(drbg->ctr_null_value_buf);
+	drbg->ctr_null_value = NULL;
+
+	return 0;
+}
+
+static void drbg_skcipher_cb(struct crypto_async_request *req, int error)
+{
+	struct drbg_state *drbg = req->data;
+
+	if (error == -EINPROGRESS)
+		return;
+	drbg->ctr_async_err = error;
+	complete(&drbg->ctr_completion);
+}
+
+#define DRBG_CTR_NULL_LEN 128
 static int drbg_init_sym_kernel(struct drbg_state *drbg)
 {
-	int ret = 0;
 	struct crypto_cipher *tfm;
+	struct crypto_skcipher *sk_tfm;
+	struct skcipher_request *req;
+	unsigned int alignmask;
+	char ctr_name[CRYPTO_MAX_ALG_NAME];
 
 	tfm = crypto_alloc_cipher(drbg->core->backend_cra_name, 0, 0);
 	if (IS_ERR(tfm)) {
@@ -1647,16 +1670,41 @@ static int drbg_init_sym_kernel(struct drbg_state *drbg)
 	}
 	BUG_ON(drbg_blocklen(drbg) != crypto_cipher_blocksize(tfm));
 	drbg->priv_data = tfm;
-	return ret;
-}
 
-static int drbg_fini_sym_kernel(struct drbg_state *drbg)
-{
-	struct crypto_cipher *tfm =
-		(struct crypto_cipher *)drbg->priv_data;
-	if (tfm)
-		crypto_free_cipher(tfm);
-	drbg->priv_data = NULL;
+	if (snprintf(ctr_name, CRYPTO_MAX_ALG_NAME, "ctr(%s)",
+	    drbg->core->backend_cra_name) >= CRYPTO_MAX_ALG_NAME) {
+		drbg_fini_sym_kernel(drbg);
+		return -EINVAL;
+	}
+	sk_tfm = crypto_alloc_skcipher(ctr_name, 0, 0);
+	if (IS_ERR(sk_tfm)) {
+		pr_info("DRBG: could not allocate CTR cipher TFM handle: %s\n",
+				ctr_name);
+		drbg_fini_sym_kernel(drbg);
+		return PTR_ERR(sk_tfm);
+	}
+	drbg->ctr_handle = sk_tfm;
+
+	req = skcipher_request_alloc(sk_tfm, GFP_KERNEL);
+	if (!req) {
+		pr_info("DRBG: could not allocate request queue\n");
+		drbg_fini_sym_kernel(drbg);
+		return PTR_ERR(req);
+	}
+	drbg->ctr_req = req;
+	skcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG,
+					drbg_skcipher_cb, drbg);
+
+	alignmask = crypto_skcipher_alignmask(sk_tfm);
+	drbg->ctr_null_value_buf = kzalloc(DRBG_CTR_NULL_LEN + alignmask,
+					   GFP_KERNEL);
+	if (!drbg->ctr_null_value_buf) {
+		drbg_fini_sym_kernel(drbg);
+		return -ENOMEM;
+	}
+	drbg->ctr_null_value = (u8 *)PTR_ALIGN(drbg->ctr_null_value_buf,
+					       alignmask + 1);
+
 	return 0;
 }
 
@@ -1680,6 +1728,43 @@ static int drbg_kcapi_sym(struct drbg_state *drbg, unsigned char *outval,
 	crypto_cipher_encrypt_one(tfm, outval, in->buf);
 	return 0;
 }
+
+static int drbg_kcapi_sym_ctr(struct drbg_state *drbg, u8 *outbuf, u32 outlen)
+{
+	struct scatterlist sg_in;
+
+	sg_init_one(&sg_in, drbg->ctr_null_value, DRBG_CTR_NULL_LEN);
+
+	while (outlen) {
+		u32 cryptlen = min_t(u32, outlen, DRBG_CTR_NULL_LEN);
+		struct scatterlist sg_out;
+		int ret;
+
+		sg_init_one(&sg_out, outbuf, cryptlen);
+		skcipher_request_set_crypt(drbg->ctr_req, &sg_in, &sg_out,
+					   cryptlen, drbg->V);
+		ret = crypto_skcipher_encrypt(drbg->ctr_req);
+		switch (ret) {
+		case 0:
+			break;
+		case -EINPROGRESS:
+		case -EBUSY:
+			ret = wait_for_completion_interruptible(
+				&drbg->ctr_completion);
+			if (!ret && !drbg->ctr_async_err) {
+				reinit_completion(&drbg->ctr_completion);
+				break;
+			}
+		default:
+			return ret;
+		}
+		init_completion(&drbg->ctr_completion);
+
+		outlen -= cryptlen;
+	}
+
+	return 0;
+}
 #endif /* CONFIG_CRYPTO_DRBG_CTR */
 
 /***************************************************************
diff --git a/include/crypto/drbg.h b/include/crypto/drbg.h
index d961b2b..b2fe15d 100644
--- a/include/crypto/drbg.h
+++ b/include/crypto/drbg.h
@@ -43,6 +43,7 @@
 #include <linux/random.h>
 #include <linux/scatterlist.h>
 #include <crypto/hash.h>
+#include <crypto/skcipher.h>
 #include <linux/module.h>
 #include <linux/crypto.h>
 #include <linux/slab.h>
@@ -115,6 +116,14 @@ struct drbg_state {
 	 /* some memory the DRBG can use for its operation */
 	unsigned char *scratchpad;
 	void *priv_data;	/* Cipher handle */
+
+	struct crypto_skcipher *ctr_handle;	/* CTR mode cipher handle */
+	struct skcipher_request *ctr_req;	/* CTR mode request handle */
+	__u8 *ctr_null_value_buf;		/* CTR mode unaligned buffer */
+	__u8 *ctr_null_value;			/* CTR mode aligned zero buf */
+	struct completion ctr_completion;	/* CTR mode async handler */
+	int ctr_async_err;			/* CTR mode async error */
+
 	bool seeded;		/* DRBG fully seeded? */
 	bool pr;		/* Prediction resistance enabled? */
 	struct work_struct seed_work;	/* asynchronous seeding support */
-- 
2.5.5

^ permalink raw reply related

* [PATCH v2 3/4] crypto: CTR DRBG - use full CTR AES for update
From: Stephan Mueller @ 2016-06-14  5:35 UTC (permalink / raw)
  To: herbert; +Cc: linux-crypto
In-Reply-To: <1842774.dgV8IOeQEu@positron.chronox.de>

The CTR DRBG update function performs a full CTR AES operation including
the XOR with "plaintext" data. Hence, remove the XOR from the code and
use the CTR mode to do the XOR.

Signed-off-by: Stephan Mueller <smueller@chronox.de>
---
 crypto/drbg.c | 30 +++++++++++++-----------------
 1 file changed, 13 insertions(+), 17 deletions(-)

diff --git a/crypto/drbg.c b/crypto/drbg.c
index 8ac3ea1..8ceb716 100644
--- a/crypto/drbg.c
+++ b/crypto/drbg.c
@@ -258,7 +258,10 @@ static int drbg_kcapi_sym(struct drbg_state *drbg, unsigned char *outval,
 			  const struct drbg_string *in);
 static int drbg_init_sym_kernel(struct drbg_state *drbg);
 static int drbg_fini_sym_kernel(struct drbg_state *drbg);
-static int drbg_kcapi_sym_ctr(struct drbg_state *drbg, u8 *outbuf, u32 outlen);
+static int drbg_kcapi_sym_ctr(struct drbg_state *drbg,
+			      u8 *inbuf, u32 inbuflen,
+			      u8 *outbuf, u32 outlen);
+#define DRBG_CTR_NULL_LEN 128
 
 /* BCC function for CTR DRBG as defined in 10.4.3 */
 static int drbg_ctr_bcc(struct drbg_state *drbg,
@@ -481,8 +484,6 @@ static int drbg_ctr_update(struct drbg_state *drbg, struct list_head *seed,
 	unsigned char *temp = drbg->scratchpad;
 	unsigned char *df_data = drbg->scratchpad + drbg_statelen(drbg) +
 				 drbg_blocklen(drbg);
-	unsigned char *temp_p, *df_data_p; /* pointer to iterate over buffers */
-	unsigned int len = 0;
 
 	if (3 > reseed)
 		memset(df_data, 0, drbg_statelen(drbg));
@@ -510,18 +511,11 @@ static int drbg_ctr_update(struct drbg_state *drbg, struct list_head *seed,
 			goto out;
 	}
 
-	ret = drbg_kcapi_sym_ctr(drbg, temp, drbg_statelen(drbg));
+	ret = drbg_kcapi_sym_ctr(drbg, df_data, drbg_statelen(drbg),
+				 temp, drbg_statelen(drbg));
 	if (ret)
 		return ret;
 
-	/* 10.2.1.2 step 4 */
-	temp_p = temp;
-	df_data_p = df_data;
-	for (len = 0; len < drbg_statelen(drbg); len++) {
-		*temp_p ^= *df_data_p;
-		df_data_p++; temp_p++;
-	}
-
 	/* 10.2.1.2 step 5 */
 	memcpy(drbg->C, temp, drbg_keylen(drbg));
 	ret = crypto_skcipher_setkey(drbg->ctr_handle, drbg->C,
@@ -561,7 +555,8 @@ static int drbg_ctr_generate(struct drbg_state *drbg,
 	}
 
 	/* 10.2.1.5.2 step 4.1 */
-	ret = drbg_kcapi_sym_ctr(drbg, buf, len);
+	ret = drbg_kcapi_sym_ctr(drbg, drbg->ctr_null_value, DRBG_CTR_NULL_LEN,
+				 buf, len);
 	if (ret)
 		return ret;
 
@@ -1657,7 +1652,6 @@ static void drbg_skcipher_cb(struct crypto_async_request *req, int error)
 	complete(&drbg->ctr_completion);
 }
 
-#define DRBG_CTR_NULL_LEN 128
 static int drbg_init_sym_kernel(struct drbg_state *drbg)
 {
 	struct crypto_cipher *tfm;
@@ -1733,14 +1727,16 @@ static int drbg_kcapi_sym(struct drbg_state *drbg, unsigned char *outval,
 	return 0;
 }
 
-static int drbg_kcapi_sym_ctr(struct drbg_state *drbg, u8 *outbuf, u32 outlen)
+static int drbg_kcapi_sym_ctr(struct drbg_state *drbg,
+			      u8 *inbuf, u32 inlen,
+			      u8 *outbuf, u32 outlen)
 {
 	struct scatterlist sg_in;
 
-	sg_init_one(&sg_in, drbg->ctr_null_value, DRBG_CTR_NULL_LEN);
+	sg_init_one(&sg_in, inbuf, inlen);
 
 	while (outlen) {
-		u32 cryptlen = min_t(u32, outlen, DRBG_CTR_NULL_LEN);
+		u32 cryptlen = min_t(u32, inlen, outlen);
 		struct scatterlist sg_out;
 		int ret;
 
-- 
2.5.5

^ permalink raw reply related

* [PATCH v2 2/4] crypto: DRBG - use aligned buffers
From: Stephan Mueller @ 2016-06-14  5:35 UTC (permalink / raw)
  To: herbert; +Cc: linux-crypto
In-Reply-To: <1842774.dgV8IOeQEu@positron.chronox.de>

Hardware cipher implementation may require aligned buffers. All buffers
that potentially are processed with a cipher are now aligned.

At the time of the allocation of the memory, we have not yet allocated
the cipher implementations. Hence, we cannot obtain the alignmask for
the used cipher yet. Therefore, the DRBG code uses an alignment which
should satisfy all cipher implementations.

Signed-off-by: Stephan Mueller <smueller@chronox.de>
---
 crypto/drbg.c         | 44 ++++++++++++++++++++++++--------------------
 include/crypto/drbg.h |  3 +++
 2 files changed, 27 insertions(+), 20 deletions(-)

diff --git a/crypto/drbg.c b/crypto/drbg.c
index 4ee1a9c..8ac3ea1 100644
--- a/crypto/drbg.c
+++ b/crypto/drbg.c
@@ -1139,11 +1139,11 @@ static inline void drbg_dealloc_state(struct drbg_state *drbg)
 	if (!drbg)
 		return;
 	kzfree(drbg->V);
-	drbg->V = NULL;
+	drbg->Vbuf = NULL;
 	kzfree(drbg->C);
-	drbg->C = NULL;
-	kzfree(drbg->scratchpad);
-	drbg->scratchpad = NULL;
+	drbg->Cbuf = NULL;
+	kzfree(drbg->scratchpadbuf);
+	drbg->scratchpadbuf = NULL;
 	drbg->reseed_ctr = 0;
 	drbg->d_ops = NULL;
 	drbg->core = NULL;
@@ -1179,12 +1179,18 @@ static inline int drbg_alloc_state(struct drbg_state *drbg)
 		goto err;
 	}
 
-	drbg->V = kmalloc(drbg_statelen(drbg), GFP_KERNEL);
-	if (!drbg->V)
-		goto err;
-	drbg->C = kmalloc(drbg_statelen(drbg), GFP_KERNEL);
-	if (!drbg->C)
+	ret = drbg->d_ops->crypto_init(drbg);
+	if (ret < 0)
 		goto err;
+
+	drbg->Vbuf = kmalloc(drbg_statelen(drbg) + ret, GFP_KERNEL);
+	if (!drbg->Vbuf)
+		goto fini;
+	drbg->V = PTR_ALIGN(drbg->Vbuf, ret + 1);
+	drbg->Cbuf = kmalloc(drbg_statelen(drbg) + ret, GFP_KERNEL);
+	if (!drbg->Cbuf)
+		goto fini;
+	drbg->C = PTR_ALIGN(drbg->Cbuf, ret + 1);
 	/* scratchpad is only generated for CTR and Hash */
 	if (drbg->core->flags & DRBG_HMAC)
 		sb_size = 0;
@@ -1198,13 +1204,16 @@ static inline int drbg_alloc_state(struct drbg_state *drbg)
 		sb_size = drbg_statelen(drbg) + drbg_blocklen(drbg);
 
 	if (0 < sb_size) {
-		drbg->scratchpad = kzalloc(sb_size, GFP_KERNEL);
-		if (!drbg->scratchpad)
-			goto err;
+		drbg->scratchpadbuf = kzalloc(sb_size + ret, GFP_KERNEL);
+		if (!drbg->scratchpadbuf)
+			goto fini;
+		drbg->scratchpad = PTR_ALIGN(drbg->scratchpadbuf, ret + 1);
 	}
 
 	return 0;
 
+fini:
+	drbg->d_ops->crypto_fini(drbg);
 err:
 	drbg_dealloc_state(drbg);
 	return ret;
@@ -1472,10 +1481,6 @@ static int drbg_instantiate(struct drbg_state *drbg, struct drbg_string *pers,
 		if (ret)
 			goto unlock;
 
-		ret = -EFAULT;
-		if (drbg->d_ops->crypto_init(drbg))
-			goto err;
-
 		ret = drbg_prepare_hrng(drbg);
 		if (ret)
 			goto free_everything;
@@ -1499,8 +1504,6 @@ static int drbg_instantiate(struct drbg_state *drbg, struct drbg_string *pers,
 	mutex_unlock(&drbg->drbg_mutex);
 	return ret;
 
-err:
-	drbg_dealloc_state(drbg);
 unlock:
 	mutex_unlock(&drbg->drbg_mutex);
 	return ret;
@@ -1585,7 +1588,8 @@ static int drbg_init_hash_kernel(struct drbg_state *drbg)
 	sdesc->shash.tfm = tfm;
 	sdesc->shash.flags = 0;
 	drbg->priv_data = sdesc;
-	return 0;
+
+	return crypto_shash_alignmask(tfm);
 }
 
 static int drbg_fini_hash_kernel(struct drbg_state *drbg)
@@ -1705,7 +1709,7 @@ static int drbg_init_sym_kernel(struct drbg_state *drbg)
 	drbg->ctr_null_value = (u8 *)PTR_ALIGN(drbg->ctr_null_value_buf,
 					       alignmask + 1);
 
-	return 0;
+	return alignmask;
 }
 
 static void drbg_kcapi_symsetkey(struct drbg_state *drbg,
diff --git a/include/crypto/drbg.h b/include/crypto/drbg.h
index b2fe15d..61580b1 100644
--- a/include/crypto/drbg.h
+++ b/include/crypto/drbg.h
@@ -108,13 +108,16 @@ struct drbg_test_data {
 struct drbg_state {
 	struct mutex drbg_mutex;	/* lock around DRBG */
 	unsigned char *V;	/* internal state 10.1.1.1 1a) */
+	unsigned char *Vbuf;
 	/* hash: static value 10.1.1.1 1b) hmac / ctr: key */
 	unsigned char *C;
+	unsigned char *Cbuf;
 	/* Number of RNG requests since last reseed -- 10.1.1.1 1c) */
 	size_t reseed_ctr;
 	size_t reseed_threshold;
 	 /* some memory the DRBG can use for its operation */
 	unsigned char *scratchpad;
+	unsigned char *scratchpadbuf;
 	void *priv_data;	/* Cipher handle */
 
 	struct crypto_skcipher *ctr_handle;	/* CTR mode cipher handle */
-- 
2.5.5

^ permalink raw reply related

* [PATCH v2 4/4] crypto: CTR DRBG - avoid duplicate maintenance of key
From: Stephan Mueller @ 2016-06-14  5:36 UTC (permalink / raw)
  To: herbert; +Cc: linux-crypto
In-Reply-To: <1842774.dgV8IOeQEu@positron.chronox.de>

The TFM object maintains the key for the CTR DRBG.

Signed-off-by: Stephan Mueller <smueller@chronox.de>
---
 crypto/drbg.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/crypto/drbg.c b/crypto/drbg.c
index 8ceb716..ded8638 100644
--- a/crypto/drbg.c
+++ b/crypto/drbg.c
@@ -517,8 +517,7 @@ static int drbg_ctr_update(struct drbg_state *drbg, struct list_head *seed,
 		return ret;
 
 	/* 10.2.1.2 step 5 */
-	memcpy(drbg->C, temp, drbg_keylen(drbg));
-	ret = crypto_skcipher_setkey(drbg->ctr_handle, drbg->C,
+	ret = crypto_skcipher_setkey(drbg->ctr_handle, temp,
 				     drbg_keylen(drbg));
 	if (ret)
 		goto out;
-- 
2.5.5

^ permalink raw reply related

* Re: [PATCH v6 3/6] crypto: AF_ALG -- add asymmetric cipher interface
From: Andrew Zaborowski @ 2016-06-14  7:42 UTC (permalink / raw)
  To: Stephan Mueller
  Cc: Mat Martineau, Tadeusz Struk, David Howells, Herbert Xu,
	linux-api-u79uwXL29TY76Z2rM5mHXA, marcel-kz+m5ild9QBg9hUCZPvPmw,
	linux-kernel-u79uwXL29TY76Z2rM5mHXA,
	keyrings-u79uwXL29TY76Z2rM5mHXA, Linux Crypto Mailing List,
	David Woodhouse, davem-fT/PcQaiUtIeIZ0/mPfg9Q
In-Reply-To: <1759070.fi90mrsgKn-jJGQKZiSfeo1haGO/jJMPxvVK+yQ3ZXh@public.gmane.org>

Hi Stephan,

On 14 June 2016 at 07:12, Stephan Mueller <smueller-T9tCv8IpfcWELgA04lAiVw@public.gmane.org> wrote:
> Am Dienstag, 14. Juni 2016, 00:16:11 schrieb Andrew Zaborowski:
>> On 8 June 2016 at 21:14, Mat Martineau
>>
>> <mathew.j.martineau-VuQAYsv1563Yd54FQh9/CA@public.gmane.org> wrote:
>> > On Wed, 8 Jun 2016, Stephan Mueller wrote:
>> >> What is your concern?
>> >
>> > Userspace must allocate larger buffers than it knows are necessary for
>> > expected results.
>> >
>> > It looks like the software rsa implementation handles shorter output
>> > buffers ok (mpi_write_to_sgl will return EOVERFLOW if the the buffer is
>> > too small), however I see at least one hardware rsa driver that requires
>> > the output buffer to be the maximum size. But this inconsistency might be
>> > best addressed within the software cipher or drivers rather than in
>> > recvmsg.
>> Should the hardware drivers fix this instead?  I've looked at the qat
>> and caam drivers, they both require the destination buffer size to be
>> the key size and in both cases there would be no penalty for dropping
>> this requirement as far as I see.  Both do a memmove if the result
>> ends up being shorter than key size.  In case the caller knows it is
>> expecting a specific output size, the driver will have to use a self
>> allocated buffer + a memcpy in those same cases where it would later
>> use memmove instead.  Alternatively the sg passed to dma_map_sg can be
>> prepended with a dummy segment the right size to save the memcpy.
>>
>> akcipher.h only says:
>> @dst_len: Size of the output buffer. It needs to be at least as big as
>> the expected result depending on the operation
>>
>> Note that for random input data the memmove will be done about 1 in
>> 256 times but with PKCS#1 padding the signature always has a leading
>> zero.
>>
>> Requiring buffers bigger than needed makes the added work of dropping
>> the zero bytes from the sglist and potentially re-adding them in the
>> client difficult to justify.  RSA doing this sets a precedent for a
>> future pkcs1pad (or other algorithm) implementation to do the same
>> thing and a portable client having to always know the key size and use
>> key-sized buffers.
>
> I think we have agreed on dropping the length enforcement at the interface
> level.

Separately from this there's a problem with the user being unable to
know if the algorithm is going to fail because of destination buffer
size != key size (including kernel users).  For RSA, the qat
implementation will fail while the software implementation won't.  For
pkcs1pad(...) there's currently just one implementation but the user
can't assume that.

Best regards

^ permalink raw reply

* Re: [PATCH v2 0/3] hw_random: Add Amlogic Meson SoCs Random Generator driver
From: Herbert Xu @ 2016-06-14 10:33 UTC (permalink / raw)
  To: Kevin Hilman
  Cc: Neil Armstrong, linux-crypto, linux-amlogic, linux-kernel,
	linux-arm-kernel, Matt Mackall
In-Reply-To: <m2wplsviy3.fsf@baylibre.com>

On Mon, Jun 13, 2016 at 03:10:28PM -0700, Kevin Hilman wrote:
> Could you take just the driver please?
> 
> Due to lots of other activity in the DT, I'd prefer to send the DT &
> bindings though the arm-soc (via the amlogic tree.)

OK I will back out these two patches.

Cheers,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt

^ permalink raw reply

* Re: [PATCH v4] crypto: rsa - return raw integers for the ASN.1 parser
From: Herbert Xu @ 2016-06-14 11:20 UTC (permalink / raw)
  To: Tudor Ambarus; +Cc: smueller, linux-crypto
In-Reply-To: <1465827173-16916-1-git-send-email-tudor-dan.ambarus@nxp.com>

On Mon, Jun 13, 2016 at 05:12:53PM +0300, Tudor Ambarus wrote:
> +
> +struct rsa_ctx {
> +	struct rsa_key key;

This isn't necessary and worse it may lead to bugs in future.
The raw keys will be invalid as soon as the setkey functions
return.

So just store it on the stack.

Thanks,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt

^ permalink raw reply

* Re: [PATCH v8 1/3] crypto: Key-agreement Protocol Primitives API (KPP)
From: Herbert Xu @ 2016-06-14 11:34 UTC (permalink / raw)
  To: Salvatore Benedetto; +Cc: linux-crypto
In-Reply-To: <1465854948-9084-2-git-send-email-salvatore.benedetto@intel.com>

On Mon, Jun 13, 2016 at 10:55:46PM +0100, Salvatore Benedetto wrote:
>
> +struct kpp_alg {
> +	int (*set_secret)(struct crypto_kpp *tfm, void *buffer);

Sorry I think we need to change this.  Leaving this with no type
checking between the user and the driver is a recipe for disaster.

I think the easiest solution is to use either BER encoding like
rsa.c or netlink encoding like authenc.c.

Cheers,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt

^ permalink raw reply

* [PATCH v5] crypto: rsa - return raw integers for the ASN.1 parser
From: Tudor Ambarus @ 2016-06-14 13:14 UTC (permalink / raw)
  To: herbert; +Cc: smueller, linux-crypto, Tudor Ambarus

Return the raw key with no other processing so that the caller
can copy it or MPI parse it, etc.

The scope is to have only one ANS.1 parser for all RSA
implementations.

Update the RSA software implementation so that it does
the MPI conversion on top.

Signed-off-by: Tudor Ambarus <tudor-dan.ambarus@nxp.com>
---
Changes in v5:
	- store raw keys on stack

Changes in v4:
1. Remove the skipping of leading zeros from rsa_get_n/e/d helper functions.
2. Remove FIPS RSA key length checking for the RSA private exponent.
FIPS check is done only for the RSA modulus.


 crypto/rsa.c                  | 105 +++++++++++++++++++++++++++++----------
 crypto/rsa_helper.c           | 111 +++++++++++++++---------------------------
 include/crypto/internal/rsa.h |  22 ++++++---
 3 files changed, 135 insertions(+), 103 deletions(-)

diff --git a/crypto/rsa.c b/crypto/rsa.c
index 77d737f..dc692d4 100644
--- a/crypto/rsa.c
+++ b/crypto/rsa.c
@@ -10,16 +10,23 @@
  */
 
 #include <linux/module.h>
+#include <linux/mpi.h>
 #include <crypto/internal/rsa.h>
 #include <crypto/internal/akcipher.h>
 #include <crypto/akcipher.h>
 #include <crypto/algapi.h>
 
+struct rsa_mpi_key {
+	MPI n;
+	MPI e;
+	MPI d;
+};
+
 /*
  * RSAEP function [RFC3447 sec 5.1.1]
  * c = m^e mod n;
  */
-static int _rsa_enc(const struct rsa_key *key, MPI c, MPI m)
+static int _rsa_enc(const struct rsa_mpi_key *key, MPI c, MPI m)
 {
 	/* (1) Validate 0 <= m < n */
 	if (mpi_cmp_ui(m, 0) < 0 || mpi_cmp(m, key->n) >= 0)
@@ -33,7 +40,7 @@ static int _rsa_enc(const struct rsa_key *key, MPI c, MPI m)
  * RSADP function [RFC3447 sec 5.1.2]
  * m = c^d mod n;
  */
-static int _rsa_dec(const struct rsa_key *key, MPI m, MPI c)
+static int _rsa_dec(const struct rsa_mpi_key *key, MPI m, MPI c)
 {
 	/* (1) Validate 0 <= c < n */
 	if (mpi_cmp_ui(c, 0) < 0 || mpi_cmp(c, key->n) >= 0)
@@ -47,7 +54,7 @@ static int _rsa_dec(const struct rsa_key *key, MPI m, MPI c)
  * RSASP1 function [RFC3447 sec 5.2.1]
  * s = m^d mod n
  */
-static int _rsa_sign(const struct rsa_key *key, MPI s, MPI m)
+static int _rsa_sign(const struct rsa_mpi_key *key, MPI s, MPI m)
 {
 	/* (1) Validate 0 <= m < n */
 	if (mpi_cmp_ui(m, 0) < 0 || mpi_cmp(m, key->n) >= 0)
@@ -61,7 +68,7 @@ static int _rsa_sign(const struct rsa_key *key, MPI s, MPI m)
  * RSAVP1 function [RFC3447 sec 5.2.2]
  * m = s^e mod n;
  */
-static int _rsa_verify(const struct rsa_key *key, MPI m, MPI s)
+static int _rsa_verify(const struct rsa_mpi_key *key, MPI m, MPI s)
 {
 	/* (1) Validate 0 <= s < n */
 	if (mpi_cmp_ui(s, 0) < 0 || mpi_cmp(s, key->n) >= 0)
@@ -71,7 +78,7 @@ static int _rsa_verify(const struct rsa_key *key, MPI m, MPI s)
 	return mpi_powm(m, s, key->e, key->n);
 }
 
-static inline struct rsa_key *rsa_get_key(struct crypto_akcipher *tfm)
+static inline struct rsa_mpi_key *rsa_get_key(struct crypto_akcipher *tfm)
 {
 	return akcipher_tfm_ctx(tfm);
 }
@@ -79,7 +86,7 @@ static inline struct rsa_key *rsa_get_key(struct crypto_akcipher *tfm)
 static int rsa_enc(struct akcipher_request *req)
 {
 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
-	const struct rsa_key *pkey = rsa_get_key(tfm);
+	const struct rsa_mpi_key *pkey = rsa_get_key(tfm);
 	MPI m, c = mpi_alloc(0);
 	int ret = 0;
 	int sign;
@@ -118,7 +125,7 @@ err_free_c:
 static int rsa_dec(struct akcipher_request *req)
 {
 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
-	const struct rsa_key *pkey = rsa_get_key(tfm);
+	const struct rsa_mpi_key *pkey = rsa_get_key(tfm);
 	MPI c, m = mpi_alloc(0);
 	int ret = 0;
 	int sign;
@@ -156,7 +163,7 @@ err_free_m:
 static int rsa_sign(struct akcipher_request *req)
 {
 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
-	const struct rsa_key *pkey = rsa_get_key(tfm);
+	const struct rsa_mpi_key *pkey = rsa_get_key(tfm);
 	MPI m, s = mpi_alloc(0);
 	int ret = 0;
 	int sign;
@@ -195,7 +202,7 @@ err_free_s:
 static int rsa_verify(struct akcipher_request *req)
 {
 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
-	const struct rsa_key *pkey = rsa_get_key(tfm);
+	const struct rsa_mpi_key *pkey = rsa_get_key(tfm);
 	MPI s, m = mpi_alloc(0);
 	int ret = 0;
 	int sign;
@@ -233,6 +240,16 @@ err_free_m:
 	return ret;
 }
 
+static void rsa_free_mpi_key(struct rsa_mpi_key *key)
+{
+	mpi_free(key->d);
+	mpi_free(key->e);
+	mpi_free(key->n);
+	key->d = NULL;
+	key->e = NULL;
+	key->n = NULL;
+}
+
 static int rsa_check_key_length(unsigned int len)
 {
 	switch (len) {
@@ -251,49 +268,87 @@ static int rsa_check_key_length(unsigned int len)
 static int rsa_set_pub_key(struct crypto_akcipher *tfm, const void *key,
 			   unsigned int keylen)
 {
-	struct rsa_key *pkey = akcipher_tfm_ctx(tfm);
+	struct rsa_mpi_key *mpi_key = akcipher_tfm_ctx(tfm);
+	struct rsa_key raw_key = {0};
 	int ret;
 
-	ret = rsa_parse_pub_key(pkey, key, keylen);
+	/* Free the old MPI key if any */
+	rsa_free_mpi_key(mpi_key);
+
+	ret = rsa_parse_pub_key(&raw_key, key, keylen);
 	if (ret)
 		return ret;
 
-	if (rsa_check_key_length(mpi_get_size(pkey->n) << 3)) {
-		rsa_free_key(pkey);
-		ret = -EINVAL;
+	mpi_key->e = mpi_read_raw_data(raw_key.e, raw_key.e_sz);
+	if (!mpi_key->e)
+		goto err;
+
+	mpi_key->n = mpi_read_raw_data(raw_key.n, raw_key.n_sz);
+	if (!mpi_key->n)
+		goto err;
+
+	if (rsa_check_key_length(mpi_get_size(mpi_key->n) << 3)) {
+		rsa_free_mpi_key(mpi_key);
+		return -EINVAL;
 	}
-	return ret;
+
+	return 0;
+
+err:
+	rsa_free_mpi_key(mpi_key);
+	return -ENOMEM;
 }
 
 static int rsa_set_priv_key(struct crypto_akcipher *tfm, const void *key,
 			    unsigned int keylen)
 {
-	struct rsa_key *pkey = akcipher_tfm_ctx(tfm);
+	struct rsa_mpi_key *mpi_key = akcipher_tfm_ctx(tfm);
+	struct rsa_key raw_key = {0};
 	int ret;
 
-	ret = rsa_parse_priv_key(pkey, key, keylen);
+	/* Free the old MPI key if any */
+	rsa_free_mpi_key(mpi_key);
+
+	ret = rsa_parse_priv_key(&raw_key, key, keylen);
 	if (ret)
 		return ret;
 
-	if (rsa_check_key_length(mpi_get_size(pkey->n) << 3)) {
-		rsa_free_key(pkey);
-		ret = -EINVAL;
+	mpi_key->d = mpi_read_raw_data(raw_key.d, raw_key.d_sz);
+	if (!mpi_key->d)
+		goto err;
+
+	mpi_key->e = mpi_read_raw_data(raw_key.e, raw_key.e_sz);
+	if (!mpi_key->e)
+		goto err;
+
+	mpi_key->n = mpi_read_raw_data(raw_key.n, raw_key.n_sz);
+	if (!mpi_key->n)
+		goto err;
+
+	if (rsa_check_key_length(mpi_get_size(mpi_key->n) << 3)) {
+		rsa_free_mpi_key(mpi_key);
+		return -EINVAL;
 	}
-	return ret;
+
+	return 0;
+
+err:
+	rsa_free_mpi_key(mpi_key);
+	return -ENOMEM;
 }
 
 static int rsa_max_size(struct crypto_akcipher *tfm)
 {
-	struct rsa_key *pkey = akcipher_tfm_ctx(tfm);
+	struct rsa_mpi_key *pkey = akcipher_tfm_ctx(tfm);
 
 	return pkey->n ? mpi_get_size(pkey->n) : -EINVAL;
 }
 
 static void rsa_exit_tfm(struct crypto_akcipher *tfm)
 {
-	struct rsa_key *pkey = akcipher_tfm_ctx(tfm);
+	struct rsa_mpi_key *pkey = akcipher_tfm_ctx(tfm);
 
-	rsa_free_key(pkey);
+	rsa_free_mpi_key(pkey);
 }
 
 static struct akcipher_alg rsa = {
@@ -310,7 +365,7 @@ static struct akcipher_alg rsa = {
 		.cra_driver_name = "rsa-generic",
 		.cra_priority = 100,
 		.cra_module = THIS_MODULE,
-		.cra_ctxsize = sizeof(struct rsa_key),
+		.cra_ctxsize = sizeof(struct rsa_mpi_key),
 	},
 };
 
diff --git a/crypto/rsa_helper.c b/crypto/rsa_helper.c
index d226f48..583656a 100644
--- a/crypto/rsa_helper.c
+++ b/crypto/rsa_helper.c
@@ -22,20 +22,29 @@ int rsa_get_n(void *context, size_t hdrlen, unsigned char tag,
 	      const void *value, size_t vlen)
 {
 	struct rsa_key *key = context;
+	const u8 *ptr = value;
+	size_t n_sz = vlen;
 
-	key->n = mpi_read_raw_data(value, vlen);
-
-	if (!key->n)
-		return -ENOMEM;
-
-	/* In FIPS mode only allow key size 2K & 3K */
-	if (fips_enabled && (mpi_get_size(key->n) != 256 &&
-			     mpi_get_size(key->n) != 384)) {
-		pr_err("RSA: key size not allowed in FIPS mode\n");
-		mpi_free(key->n);
-		key->n = NULL;
+	/* invalid key provided */
+	if (!value || !vlen)
 		return -EINVAL;
+
+	if (fips_enabled) {
+		while (!*ptr && n_sz) {
+			ptr++;
+			n_sz--;
+		}
+
+		/* In FIPS mode only allow key size 2K & 3K */
+		if (n_sz != 256 && n_sz != 384) {
+			pr_err("RSA: key size not allowed in FIPS mode\n");
+			return -EINVAL;
+		}
 	}
+
+	key->n = value;
+	key->n_sz = vlen;
+
 	return 0;
 }
 
@@ -44,10 +53,12 @@ int rsa_get_e(void *context, size_t hdrlen, unsigned char tag,
 {
 	struct rsa_key *key = context;
 
-	key->e = mpi_read_raw_data(value, vlen);
+	/* invalid key provided */
+	if (!value || !key->n_sz || !vlen || vlen > key->n_sz)
+		return -EINVAL;
 
-	if (!key->e)
-		return -ENOMEM;
+	key->e = value;
+	key->e_sz = vlen;
 
 	return 0;
 }
@@ -57,46 +68,20 @@ int rsa_get_d(void *context, size_t hdrlen, unsigned char tag,
 {
 	struct rsa_key *key = context;
 
-	key->d = mpi_read_raw_data(value, vlen);
-
-	if (!key->d)
-		return -ENOMEM;
-
-	/* In FIPS mode only allow key size 2K & 3K */
-	if (fips_enabled && (mpi_get_size(key->d) != 256 &&
-			     mpi_get_size(key->d) != 384)) {
-		pr_err("RSA: key size not allowed in FIPS mode\n");
-		mpi_free(key->d);
-		key->d = NULL;
+	/* invalid key provided */
+	if (!value || !key->n_sz || !vlen || vlen > key->n_sz)
 		return -EINVAL;
-	}
-	return 0;
-}
 
-static void free_mpis(struct rsa_key *key)
-{
-	mpi_free(key->n);
-	mpi_free(key->e);
-	mpi_free(key->d);
-	key->n = NULL;
-	key->e = NULL;
-	key->d = NULL;
-}
+	key->d = value;
+	key->d_sz = vlen;
 
-/**
- * rsa_free_key() - frees rsa key allocated by rsa_parse_key()
- *
- * @rsa_key:	struct rsa_key key representation
- */
-void rsa_free_key(struct rsa_key *key)
-{
-	free_mpis(key);
+	return 0;
 }
-EXPORT_SYMBOL_GPL(rsa_free_key);
 
 /**
- * rsa_parse_pub_key() - extracts an rsa public key from BER encoded buffer
- *			 and stores it in the provided struct rsa_key
+ * rsa_parse_pub_key() - decodes the BER encoded buffer and stores in the
+ *                       provided struct rsa_key, pointers to the raw key as is,
+ *                       so that the caller can copy it or MPI parse it, etc.
  *
  * @rsa_key:	struct rsa_key key representation
  * @key:	key in BER format
@@ -107,23 +92,15 @@ EXPORT_SYMBOL_GPL(rsa_free_key);
 int rsa_parse_pub_key(struct rsa_key *rsa_key, const void *key,
 		      unsigned int key_len)
 {
-	int ret;
-
-	free_mpis(rsa_key);
-	ret = asn1_ber_decoder(&rsapubkey_decoder, rsa_key, key, key_len);
-	if (ret < 0)
-		goto error;
-
-	return 0;
-error:
-	free_mpis(rsa_key);
-	return ret;
+	return asn1_ber_decoder(&rsapubkey_decoder, rsa_key, key, key_len);
 }
 EXPORT_SYMBOL_GPL(rsa_parse_pub_key);
 
 /**
- * rsa_parse_pub_key() - extracts an rsa private key from BER encoded buffer
- *			 and stores it in the provided struct rsa_key
+ * rsa_parse_priv_key() - decodes the BER encoded buffer and stores in the
+ *                        provided struct rsa_key, pointers to the raw key
+ *                        as is, so that the caller can copy it or MPI parse it,
+ *                        etc.
  *
  * @rsa_key:	struct rsa_key key representation
  * @key:	key in BER format
@@ -134,16 +111,6 @@ EXPORT_SYMBOL_GPL(rsa_parse_pub_key);
 int rsa_parse_priv_key(struct rsa_key *rsa_key, const void *key,
 		       unsigned int key_len)
 {
-	int ret;
-
-	free_mpis(rsa_key);
-	ret = asn1_ber_decoder(&rsaprivkey_decoder, rsa_key, key, key_len);
-	if (ret < 0)
-		goto error;
-
-	return 0;
-error:
-	free_mpis(rsa_key);
-	return ret;
+	return asn1_ber_decoder(&rsaprivkey_decoder, rsa_key, key, key_len);
 }
 EXPORT_SYMBOL_GPL(rsa_parse_priv_key);
diff --git a/include/crypto/internal/rsa.h b/include/crypto/internal/rsa.h
index c7585bd..d6c042a 100644
--- a/include/crypto/internal/rsa.h
+++ b/include/crypto/internal/rsa.h
@@ -12,12 +12,24 @@
  */
 #ifndef _RSA_HELPER_
 #define _RSA_HELPER_
-#include <linux/mpi.h>
+#include <linux/types.h>
 
+/**
+ * rsa_key - RSA key structure
+ * @n           : RSA modulus raw byte stream
+ * @e           : RSA public exponent raw byte stream
+ * @d           : RSA private exponent raw byte stream
+ * @n_sz        : length in bytes of RSA modulus n
+ * @e_sz        : length in bytes of RSA public exponent
+ * @d_sz        : length in bytes of RSA private exponent
+ */
 struct rsa_key {
-	MPI n;
-	MPI e;
-	MPI d;
+	const u8 *n;
+	const u8 *e;
+	const u8 *d;
+	size_t n_sz;
+	size_t e_sz;
+	size_t d_sz;
 };
 
 int rsa_parse_pub_key(struct rsa_key *rsa_key, const void *key,
@@ -26,7 +38,5 @@ int rsa_parse_pub_key(struct rsa_key *rsa_key, const void *key,
 int rsa_parse_priv_key(struct rsa_key *rsa_key, const void *key,
 		       unsigned int key_len);
 
-void rsa_free_key(struct rsa_key *rsa_key);
-
 extern struct crypto_template rsa_pkcs1pad_tmpl;
 #endif
-- 
1.8.3.1

^ permalink raw reply related

* Re: [PATCH v5] crypto: rsa - return raw integers for the ASN.1 parser
From: Stephan Mueller @ 2016-06-14 13:20 UTC (permalink / raw)
  To: Tudor Ambarus; +Cc: herbert, linux-crypto
In-Reply-To: <1465910098-16349-1-git-send-email-tudor-dan.ambarus@nxp.com>

Am Dienstag, 14. Juni 2016, 16:14:58 schrieb Tudor Ambarus:

Hi Tudor,

>  static int rsa_set_priv_key(struct crypto_akcipher *tfm, const void *key,
>  			    unsigned int keylen)
>  {
> -	struct rsa_key *pkey = akcipher_tfm_ctx(tfm);
> +	struct rsa_mpi_key *mpi_key = akcipher_tfm_ctx(tfm);
> +	struct rsa_key raw_key = {0};
>  	int ret;
> 
> -	ret = rsa_parse_priv_key(pkey, key, keylen);
> +	/* Free the old MPI key if any */
> +	rsa_free_mpi_key(mpi_key);
> +
> +	ret = rsa_parse_priv_key(&raw_key, key, keylen);
>  	if (ret)
>  		return ret;
> 
> -	if (rsa_check_key_length(mpi_get_size(pkey->n) << 3)) {
> -		rsa_free_key(pkey);
> -		ret = -EINVAL;
> +	mpi_key->d = mpi_read_raw_data(raw_key.d, raw_key.d_sz);
> +	if (!mpi_key->d)
> +		goto err;
> +
> +	mpi_key->e = mpi_read_raw_data(raw_key.e, raw_key.e_sz);
> +	if (!mpi_key->e)
> +		goto err;
> +
> +	mpi_key->n = mpi_read_raw_data(raw_key.n, raw_key.n_sz);
> +	if (!mpi_key->n)
> +		goto err;
> +
> +	if (rsa_check_key_length(mpi_get_size(mpi_key->n) << 3)) {
> +		rsa_free_mpi_key(mpi_key);
> +		return -EINVAL;
>  	}
> -	return ret;
> +
> +	return 0;
> +
> +err:
> +	rsa_free_mpi_key(mpi_key);
> +	return -ENOMEM;
>  }

memzero_explicit(raw_key) should be added here in success and failure code 
paths.

Ciao
Stephan

^ permalink raw reply

* Re: [PATCH v5] crypto: rsa - return raw integers for the ASN.1 parser
From: Herbert Xu @ 2016-06-14 13:38 UTC (permalink / raw)
  To: Stephan Mueller; +Cc: Tudor Ambarus, linux-crypto
In-Reply-To: <2066344.ohg9RiuaKP@tauon.atsec.com>

On Tue, Jun 14, 2016 at 03:20:06PM +0200, Stephan Mueller wrote:
>
> memzero_explicit(raw_key) should be added here in success and failure code 
> paths.

The raw_key is just a bunch of pointers, do we really need to
zero it?

Thanks,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt

^ permalink raw reply

* Re: [PATCH v5] crypto: rsa - return raw integers for the ASN.1 parser
From: Stephan Mueller @ 2016-06-14 13:53 UTC (permalink / raw)
  To: Herbert Xu; +Cc: Tudor Ambarus, linux-crypto
In-Reply-To: <20160614133806.GA22193@gondor.apana.org.au>

Am Dienstag, 14. Juni 2016, 21:38:06 schrieb Herbert Xu:

Hi Herbert,

> On Tue, Jun 14, 2016 at 03:20:06PM +0200, Stephan Mueller wrote:
> > memzero_explicit(raw_key) should be added here in success and failure code
> > paths.
> 
> The raw_key is just a bunch of pointers, do we really need to
> zero it?

You are correct.

But then I need to refine my question: isn't rsa_parse_priv_key allocating the 
MPIs (at least rsa_parse_priv_key seems to hint to that considering the error 
code path)? So, shouldn't the MPIs be freed here with free_mpis()? This would 
apply to parse_pub_key too.

Ciao
Stephan

^ permalink raw reply

* RE: [PATCH v5] crypto: rsa - return raw integers for the ASN.1 parser
From: Tudor-Dan Ambarus @ 2016-06-14 14:35 UTC (permalink / raw)
  To: Stephan Mueller, Herbert Xu; +Cc: linux-crypto@vger.kernel.org
In-Reply-To: <1920297.cMHx9vzUDS@tauon.atsec.com>

Hi Stephan,

> But then I need to refine my question: isn't rsa_parse_priv_key allocating
> the
> MPIs (at least rsa_parse_priv_key seems to hint to that considering the
> error
> code path)? So, shouldn't the MPIs be freed here with free_mpis()? This
> would
> apply to parse_pub_key too.

rsa_parse_priv_key is not allocating the MPIs, mpi_read_raw_data is.

MPIs are freed on error path. On success, they are freed when exiting
the tfm or when setting a new key.

Thanks,
ta

^ permalink raw reply

* RE: [PATCH v8 1/3] crypto: Key-agreement Protocol Primitives API (KPP)
From: Benedetto, Salvatore @ 2016-06-14 14:36 UTC (permalink / raw)
  To: Herbert Xu; +Cc: linux-crypto@vger.kernel.org, Benedetto, Salvatore
In-Reply-To: <20160614113430.GA21063@gondor.apana.org.au>


> -----Original Message-----
> From: Herbert Xu [mailto:herbert@gondor.apana.org.au]
> Sent: Tuesday, June 14, 2016 12:35 PM
> To: Benedetto, Salvatore <salvatore.benedetto@intel.com>
> Cc: linux-crypto@vger.kernel.org
> Subject: Re: [PATCH v8 1/3] crypto: Key-agreement Protocol Primitives API
> (KPP)
> 
> On Mon, Jun 13, 2016 at 10:55:46PM +0100, Salvatore Benedetto wrote:
> >
> > +struct kpp_alg {
> > +	int (*set_secret)(struct crypto_kpp *tfm, void *buffer);
> 
> Sorry I think we need to change this.  Leaving this with no type checking
> between the user and the driver is a recipe for disaster.
> 
> I think the easiest solution is to use either BER encoding like rsa.c or netlink
> encoding like authenc.c.
>

My very first patch used PKCS3 and there were some objections to that.
https://patchwork.kernel.org/patch/8311881/
 
Both Bluetooth or keyctl KEYCTL_DH_COMPUTE would have to first pack the
key to whatever format we choose and I don't see that very convinient. We
only want to provide the acceleration here, without bounding the user to a
certain key format.
 
 akcipher is different as PKCS1 is a recognized standard for RSA keys.
 
 Please don't get me wrong, it's not much of an issue for me to respin the
 patchset and change that to PKCS3 for example, but I see no harm in leaving
 it as it is and moving the key check format to whatever upper layer is using us
 (like BT and keyctl). Just more work for who is using the API.
 
 Could you reconsider that?
 
 Thanks,
 Salvatore

^ permalink raw reply

* Re: [PATCH v6 3/6] crypto: AF_ALG -- add asymmetric cipher interface
From: Mat Martineau @ 2016-06-14 17:22 UTC (permalink / raw)
  To: smueller-T9tCv8IpfcWELgA04lAiVw
  Cc: Tadeusz Struk, dhowells-H+wXaHxf7aLQT0dZR+AlfA,
	herbert-lOAM2aK0SrRLBo1qDEOMRrpzq4S04n8Q,
	linux-api-u79uwXL29TY76Z2rM5mHXA, marcel-kz+m5ild9QBg9hUCZPvPmw,
	linux-kernel-u79uwXL29TY76Z2rM5mHXA,
	keyrings-u79uwXL29TY76Z2rM5mHXA,
	linux-crypto-u79uwXL29TY76Z2rM5mHXA, dwmw2-wEGCiKHe2LqWVfeAwA7xHQ,
	davem-fT/PcQaiUtIeIZ0/mPfg9Q
In-Reply-To: <20160515041701.15888.53830.stgit@tstruk-mobl1>


Stephan,

On Sat, 14 May 2016, Tadeusz Struk wrote:

> From: Stephan Mueller <smueller-T9tCv8IpfcWELgA04lAiVw@public.gmane.org>
>
> This patch adds the user space interface for asymmetric ciphers. The
> interface allows the use of sendmsg as well as vmsplice to provide data.
>
> This version has been rebased on top of 4.6 and a few chackpatch issues
> have been fixed.
>
> Signed-off-by: Stephan Mueller <smueller-T9tCv8IpfcWELgA04lAiVw@public.gmane.org>
> Signed-off-by: Tadeusz Struk <tadeusz.struk-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> ---
> crypto/algif_akcipher.c |  542 +++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 542 insertions(+)
> create mode 100644 crypto/algif_akcipher.c
>
> diff --git a/crypto/algif_akcipher.c b/crypto/algif_akcipher.c
> new file mode 100644
> index 0000000..6342b6e
> --- /dev/null
> +++ b/crypto/algif_akcipher.c
> +
> +static int akcipher_sendmsg(struct socket *sock, struct msghdr *msg,
> +			    size_t size)
> +{
> +	struct sock *sk = sock->sk;
> +	struct alg_sock *ask = alg_sk(sk);
> +	struct akcipher_ctx *ctx = ask->private;
> +	struct akcipher_sg_list *sgl = &ctx->tsgl;
> +	struct af_alg_control con = {};
> +	long copied = 0;
> +	int op = 0;
> +	bool init = 0;
> +	int err;
> +
> +	if (msg->msg_controllen) {
> +		err = af_alg_cmsg_send(msg, &con);
> +		if (err)
> +			return err;
> +
> +		init = 1;
> +		switch (con.op) {
> +		case ALG_OP_VERIFY:
> +		case ALG_OP_SIGN:
> +		case ALG_OP_ENCRYPT:
> +		case ALG_OP_DECRYPT:
> +			op = con.op;
> +			break;
> +		default:
> +			return -EINVAL;
> +		}
> +	}
> +
> +	lock_sock(sk);
> +	if (!ctx->more && ctx->used)
> +		goto unlock;

err might be uninitialised at this goto. Should it be set to something 
like -EALREADY to indicate that data is already queued for a different 
crypto op?

<snip>

> +unlock:
> +	akcipher_data_wakeup(sk);
> +	release_sock(sk);
> +
> +	return err ?: copied;
> +}

Regards,

--
Mat Martineau
Intel OTC

^ permalink raw reply


This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox