| /* SPDX-License-Identifier: GPL-2.0-or-later */ |
| /* |
| * Key-agreement Protocol Primitives (KPP) |
| * |
| * Copyright (c) 2016, Intel Corporation |
| * Authors: Salvatore Benedetto <salvatore.benedetto@intel.com> |
| */ |
| |
| #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 |
| * |
| * @reqsize: Request context size required by algorithm |
| * implementation |
| * @base: Common crypto API algorithm data structure |
| */ |
| struct crypto_kpp { |
| unsigned int reqsize; |
| |
| 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 the 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. |
| * |
| * @base: Common crypto API algorithm data structure |
| */ |
| struct kpp_alg { |
| int (*set_secret)(struct crypto_kpp *tfm, const void *buffer, |
| unsigned int len); |
| int (*generate_public_key)(struct kpp_request *req); |
| int (*compute_shared_secret)(struct kpp_request *req); |
| |
| unsigned int (*max_size)(struct crypto_kpp *tfm); |
| |
| int (*init)(struct crypto_kpp *tfm); |
| void (*exit)(struct crypto_kpp *tfm); |
| |
| struct crypto_alg base; |
| }; |
| |
| /** |
| * DOC: Generic Key-agreement Protocol Primitives 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 required 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); |
| |
| int crypto_has_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 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); |
| } |
| |
| static inline u32 crypto_kpp_get_flags(struct crypto_kpp *tfm) |
| { |
| return crypto_tfm_get_flags(crypto_kpp_tfm(tfm)); |
| } |
| |
| static inline void crypto_kpp_set_flags(struct crypto_kpp *tfm, u32 flags) |
| { |
| crypto_tfm_set_flags(crypto_kpp_tfm(tfm), flags); |
| } |
| |
| /** |
| * crypto_free_kpp() - free KPP tfm handle |
| * |
| * @tfm: KPP tfm handle allocated with crypto_alloc_kpp() |
| * |
| * If @tfm is a NULL or error pointer, this function does nothing. |
| */ |
| 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) |
| { |
| kfree_sensitive(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; |
| } |
| |
| enum { |
| CRYPTO_KPP_SECRET_TYPE_UNKNOWN, |
| CRYPTO_KPP_SECRET_TYPE_DH, |
| CRYPTO_KPP_SECRET_TYPE_ECDH, |
| }; |
| |
| /** |
| * struct kpp_secret - small header for packing secret buffer |
| * |
| * @type: define type of secret. Each kpp type will define its own |
| * @len: specify the len of the secret, include the header, that |
| * follows the struct |
| */ |
| struct kpp_secret { |
| unsigned short type; |
| unsigned short len; |
| }; |
| |
| /** |
| * crypto_kpp_set_secret() - Invoke kpp operation |
| * |
| * Function invokes the specific kpp operation for a given alg. |
| * |
| * @tfm: tfm handle |
| * @buffer: Buffer holding the packet representation of the private |
| * key. The structure of the packet key depends on the particular |
| * KPP implementation. Packing and unpacking helpers are provided |
| * for ECDH and DH (see the respective header files for those |
| * implementations). |
| * @len: Length of the packet private key buffer. |
| * |
| * Return: zero on success; error code in case of error |
| */ |
| static inline int crypto_kpp_set_secret(struct crypto_kpp *tfm, |
| const void *buffer, unsigned int len) |
| { |
| struct kpp_alg *alg = crypto_kpp_alg(tfm); |
| struct crypto_alg *calg = tfm->base.__crt_alg; |
| int ret; |
| |
| crypto_stats_get(calg); |
| ret = alg->set_secret(tfm, buffer, len); |
| crypto_stats_kpp_set_secret(calg, ret); |
| return ret; |
| } |
| |
| /** |
| * crypto_kpp_generate_public_key() - Invoke kpp operation |
| * |
| * Function invokes the specific kpp operation for generating the public part |
| * for a given kpp algorithm. |
| * |
| * To generate a private key, the caller should use a random number generator. |
| * The output of the requested length serves as the private key. |
| * |
| * @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); |
| struct crypto_alg *calg = tfm->base.__crt_alg; |
| int ret; |
| |
| crypto_stats_get(calg); |
| ret = alg->generate_public_key(req); |
| crypto_stats_kpp_generate_public_key(calg, ret); |
| return ret; |
| } |
| |
| /** |
| * 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); |
| struct crypto_alg *calg = tfm->base.__crt_alg; |
| int ret; |
| |
| crypto_stats_get(calg); |
| ret = alg->compute_shared_secret(req); |
| crypto_stats_kpp_compute_shared_secret(calg, ret); |
| return ret; |
| } |
| |
| /** |
| * crypto_kpp_maxsize() - Get len for output buffer |
| * |
| * Function returns the output buffer size required for a given key. |
| * Function assumes that the key is already set in the transformation. If this |
| * function is called without a setkey or with a failed setkey, you will end up |
| * in a NULL dereference. |
| * |
| * @tfm: KPP tfm handle allocated with crypto_alloc_kpp() |
| */ |
| static inline unsigned int crypto_kpp_maxsize(struct crypto_kpp *tfm) |
| { |
| struct kpp_alg *alg = crypto_kpp_alg(tfm); |
| |
| return alg->max_size(tfm); |
| } |
| |
| #endif |