| /* SPDX-License-Identifier: GPL-2.0-or-later */ |
| /* |
| * Symmetric key ciphers. |
| * |
| * Copyright (c) 2007-2015 Herbert Xu <herbert@gondor.apana.org.au> |
| */ |
| |
| #ifndef _CRYPTO_SKCIPHER_H |
| #define _CRYPTO_SKCIPHER_H |
| |
| #include <linux/crypto.h> |
| #include <linux/kernel.h> |
| #include <linux/slab.h> |
| |
| /** |
| * struct skcipher_request - Symmetric key cipher request |
| * @cryptlen: Number of bytes to encrypt or decrypt |
| * @iv: Initialisation Vector |
| * @src: Source SG list |
| * @dst: Destination SG list |
| * @base: Underlying async request request |
| * @__ctx: Start of private context data |
| */ |
| struct skcipher_request { |
| unsigned int cryptlen; |
| |
| u8 *iv; |
| |
| struct scatterlist *src; |
| struct scatterlist *dst; |
| |
| struct crypto_async_request base; |
| |
| void *__ctx[] CRYPTO_MINALIGN_ATTR; |
| }; |
| |
| struct crypto_skcipher { |
| int (*setkey)(struct crypto_skcipher *tfm, const u8 *key, |
| unsigned int keylen); |
| int (*encrypt)(struct skcipher_request *req); |
| int (*decrypt)(struct skcipher_request *req); |
| |
| unsigned int ivsize; |
| unsigned int reqsize; |
| unsigned int keysize; |
| |
| struct crypto_tfm base; |
| }; |
| |
| struct crypto_sync_skcipher { |
| struct crypto_skcipher base; |
| }; |
| |
| /** |
| * struct skcipher_alg - symmetric key cipher definition |
| * @min_keysize: Minimum key size supported by the transformation. This is the |
| * smallest key length supported by this transformation algorithm. |
| * This must be set to one of the pre-defined values as this is |
| * not hardware specific. Possible values for this field can be |
| * found via git grep "_MIN_KEY_SIZE" include/crypto/ |
| * @max_keysize: Maximum key size supported by the transformation. This is the |
| * largest key length supported by this transformation algorithm. |
| * This must be set to one of the pre-defined values as this is |
| * not hardware specific. Possible values for this field can be |
| * found via git grep "_MAX_KEY_SIZE" include/crypto/ |
| * @setkey: Set key for the transformation. This function is used to either |
| * program a supplied key into the hardware or store the key in the |
| * transformation context for programming it later. Note that this |
| * function does modify the transformation context. This function can |
| * be called multiple times during the existence of the transformation |
| * object, so one must make sure the key is properly reprogrammed into |
| * the hardware. This function is also responsible for checking the key |
| * length for validity. In case a software fallback was put in place in |
| * the @cra_init call, this function might need to use the fallback if |
| * the algorithm doesn't support all of the key sizes. |
| * @encrypt: Encrypt a scatterlist of blocks. This function is used to encrypt |
| * the supplied scatterlist containing the blocks of data. The crypto |
| * API consumer is responsible for aligning the entries of the |
| * scatterlist properly and making sure the chunks are correctly |
| * sized. In case a software fallback was put in place in the |
| * @cra_init call, this function might need to use the fallback if |
| * the algorithm doesn't support all of the key sizes. In case the |
| * key was stored in transformation context, the key might need to be |
| * re-programmed into the hardware in this function. This function |
| * shall not modify the transformation context, as this function may |
| * be called in parallel with the same transformation object. |
| * @decrypt: Decrypt a single block. This is a reverse counterpart to @encrypt |
| * and the conditions are exactly the same. |
| * @init: Initialize the cryptographic transformation object. This function |
| * is used to initialize the cryptographic transformation object. |
| * This function is called only once at the instantiation time, right |
| * after the transformation context was allocated. In case the |
| * cryptographic hardware has some special requirements which need to |
| * be handled by software, this function shall check for the precise |
| * requirement of the transformation and put any software fallbacks |
| * in place. |
| * @exit: Deinitialize the cryptographic transformation object. This is a |
| * counterpart to @init, used to remove various changes set in |
| * @init. |
| * @ivsize: IV size applicable for transformation. The consumer must provide an |
| * IV of exactly that size to perform the encrypt or decrypt operation. |
| * @chunksize: Equal to the block size except for stream ciphers such as |
| * CTR where it is set to the underlying block size. |
| * @walksize: Equal to the chunk size except in cases where the algorithm is |
| * considerably more efficient if it can operate on multiple chunks |
| * in parallel. Should be a multiple of chunksize. |
| * @base: Definition of a generic crypto algorithm. |
| * |
| * All fields except @ivsize are mandatory and must be filled. |
| */ |
| struct skcipher_alg { |
| int (*setkey)(struct crypto_skcipher *tfm, const u8 *key, |
| unsigned int keylen); |
| int (*encrypt)(struct skcipher_request *req); |
| int (*decrypt)(struct skcipher_request *req); |
| int (*init)(struct crypto_skcipher *tfm); |
| void (*exit)(struct crypto_skcipher *tfm); |
| |
| unsigned int min_keysize; |
| unsigned int max_keysize; |
| unsigned int ivsize; |
| unsigned int chunksize; |
| unsigned int walksize; |
| |
| struct crypto_alg base; |
| }; |
| |
| #define MAX_SYNC_SKCIPHER_REQSIZE 384 |
| /* |
| * This performs a type-check against the "tfm" argument to make sure |
| * all users have the correct skcipher tfm for doing on-stack requests. |
| */ |
| #define SYNC_SKCIPHER_REQUEST_ON_STACK(name, tfm) \ |
| char __##name##_desc[sizeof(struct skcipher_request) + \ |
| MAX_SYNC_SKCIPHER_REQSIZE + \ |
| (!(sizeof((struct crypto_sync_skcipher *)1 == \ |
| (typeof(tfm))1))) \ |
| ] CRYPTO_MINALIGN_ATTR; \ |
| struct skcipher_request *name = (void *)__##name##_desc |
| |
| /** |
| * DOC: Symmetric Key Cipher API |
| * |
| * Symmetric key cipher API is used with the ciphers of type |
| * CRYPTO_ALG_TYPE_SKCIPHER (listed as type "skcipher" in /proc/crypto). |
| * |
| * Asynchronous cipher operations imply that the function invocation for a |
| * cipher request returns immediately before the completion of the operation. |
| * The cipher request is scheduled as a separate kernel thread and therefore |
| * load-balanced on the different CPUs via the process scheduler. To allow |
| * the kernel crypto API to inform the caller about the completion of a cipher |
| * request, the caller must provide a callback function. That function is |
| * invoked with the cipher handle when the request completes. |
| * |
| * To support the asynchronous operation, additional information than just the |
| * cipher handle must be supplied to the kernel crypto API. That additional |
| * information is given by filling in the skcipher_request data structure. |
| * |
| * For the symmetric key cipher API, the state is maintained with the tfm |
| * cipher handle. A single tfm can be used across multiple calls and in |
| * parallel. For asynchronous block cipher calls, context data supplied and |
| * only used by the caller can be referenced the request data structure in |
| * addition to the IV used for the cipher request. The maintenance of such |
| * state information would be important for a crypto driver implementer to |
| * have, because when calling the callback function upon completion of the |
| * cipher operation, that callback function may need some information about |
| * which operation just finished if it invoked multiple in parallel. This |
| * state information is unused by the kernel crypto API. |
| */ |
| |
| static inline struct crypto_skcipher *__crypto_skcipher_cast( |
| struct crypto_tfm *tfm) |
| { |
| return container_of(tfm, struct crypto_skcipher, base); |
| } |
| |
| /** |
| * crypto_alloc_skcipher() - allocate symmetric key cipher handle |
| * @alg_name: is the cra_name / name or cra_driver_name / driver name of the |
| * skcipher cipher |
| * @type: specifies the type of the cipher |
| * @mask: specifies the mask for the cipher |
| * |
| * Allocate a cipher handle for an skcipher. The returned struct |
| * crypto_skcipher is the cipher handle that is required for any subsequent |
| * API invocation for that skcipher. |
| * |
| * Return: allocated cipher handle in case of success; IS_ERR() is true in case |
| * of an error, PTR_ERR() returns the error code. |
| */ |
| struct crypto_skcipher *crypto_alloc_skcipher(const char *alg_name, |
| u32 type, u32 mask); |
| |
| struct crypto_sync_skcipher *crypto_alloc_sync_skcipher(const char *alg_name, |
| u32 type, u32 mask); |
| |
| static inline struct crypto_tfm *crypto_skcipher_tfm( |
| struct crypto_skcipher *tfm) |
| { |
| return &tfm->base; |
| } |
| |
| /** |
| * crypto_free_skcipher() - zeroize and free cipher handle |
| * @tfm: cipher handle to be freed |
| * |
| * If @tfm is a NULL or error pointer, this function does nothing. |
| */ |
| static inline void crypto_free_skcipher(struct crypto_skcipher *tfm) |
| { |
| crypto_destroy_tfm(tfm, crypto_skcipher_tfm(tfm)); |
| } |
| |
| static inline void crypto_free_sync_skcipher(struct crypto_sync_skcipher *tfm) |
| { |
| crypto_free_skcipher(&tfm->base); |
| } |
| |
| /** |
| * crypto_has_skcipher() - Search for the availability of an skcipher. |
| * @alg_name: is the cra_name / name or cra_driver_name / driver name of the |
| * skcipher |
| * @type: specifies the type of the cipher |
| * @mask: specifies the mask for the cipher |
| * |
| * Return: true when the skcipher is known to the kernel crypto API; false |
| * otherwise |
| */ |
| static inline int crypto_has_skcipher(const char *alg_name, u32 type, |
| u32 mask) |
| { |
| return crypto_has_alg(alg_name, crypto_skcipher_type(type), |
| crypto_skcipher_mask(mask)); |
| } |
| |
| /** |
| * crypto_has_skcipher2() - Search for the availability of an skcipher. |
| * @alg_name: is the cra_name / name or cra_driver_name / driver name of the |
| * skcipher |
| * @type: specifies the type of the skcipher |
| * @mask: specifies the mask for the skcipher |
| * |
| * Return: true when the skcipher is known to the kernel crypto API; false |
| * otherwise |
| */ |
| int crypto_has_skcipher2(const char *alg_name, u32 type, u32 mask); |
| |
| static inline const char *crypto_skcipher_driver_name( |
| struct crypto_skcipher *tfm) |
| { |
| return crypto_tfm_alg_driver_name(crypto_skcipher_tfm(tfm)); |
| } |
| |
| static inline struct skcipher_alg *crypto_skcipher_alg( |
| struct crypto_skcipher *tfm) |
| { |
| return container_of(crypto_skcipher_tfm(tfm)->__crt_alg, |
| struct skcipher_alg, base); |
| } |
| |
| static inline unsigned int crypto_skcipher_alg_ivsize(struct skcipher_alg *alg) |
| { |
| if ((alg->base.cra_flags & CRYPTO_ALG_TYPE_MASK) == |
| CRYPTO_ALG_TYPE_BLKCIPHER) |
| return alg->base.cra_blkcipher.ivsize; |
| |
| if (alg->base.cra_ablkcipher.encrypt) |
| return alg->base.cra_ablkcipher.ivsize; |
| |
| return alg->ivsize; |
| } |
| |
| /** |
| * crypto_skcipher_ivsize() - obtain IV size |
| * @tfm: cipher handle |
| * |
| * The size of the IV for the skcipher referenced by the cipher handle is |
| * returned. This IV size may be zero if the cipher does not need an IV. |
| * |
| * Return: IV size in bytes |
| */ |
| static inline unsigned int crypto_skcipher_ivsize(struct crypto_skcipher *tfm) |
| { |
| return tfm->ivsize; |
| } |
| |
| static inline unsigned int crypto_sync_skcipher_ivsize( |
| struct crypto_sync_skcipher *tfm) |
| { |
| return crypto_skcipher_ivsize(&tfm->base); |
| } |
| |
| /** |
| * crypto_skcipher_blocksize() - obtain block size of cipher |
| * @tfm: cipher handle |
| * |
| * The block size for the skcipher referenced with the cipher handle is |
| * returned. The caller may use that information to allocate appropriate |
| * memory for the data returned by the encryption or decryption operation |
| * |
| * Return: block size of cipher |
| */ |
| static inline unsigned int crypto_skcipher_blocksize( |
| struct crypto_skcipher *tfm) |
| { |
| return crypto_tfm_alg_blocksize(crypto_skcipher_tfm(tfm)); |
| } |
| |
| static inline unsigned int crypto_skcipher_alg_chunksize( |
| struct skcipher_alg *alg) |
| { |
| if ((alg->base.cra_flags & CRYPTO_ALG_TYPE_MASK) == |
| CRYPTO_ALG_TYPE_BLKCIPHER) |
| return alg->base.cra_blocksize; |
| |
| if (alg->base.cra_ablkcipher.encrypt) |
| return alg->base.cra_blocksize; |
| |
| return alg->chunksize; |
| } |
| |
| /** |
| * crypto_skcipher_chunksize() - obtain chunk size |
| * @tfm: cipher handle |
| * |
| * The block size is set to one for ciphers such as CTR. However, |
| * you still need to provide incremental updates in multiples of |
| * the underlying block size as the IV does not have sub-block |
| * granularity. This is known in this API as the chunk size. |
| * |
| * Return: chunk size in bytes |
| */ |
| static inline unsigned int crypto_skcipher_chunksize( |
| struct crypto_skcipher *tfm) |
| { |
| return crypto_skcipher_alg_chunksize(crypto_skcipher_alg(tfm)); |
| } |
| |
| static inline unsigned int crypto_sync_skcipher_blocksize( |
| struct crypto_sync_skcipher *tfm) |
| { |
| return crypto_skcipher_blocksize(&tfm->base); |
| } |
| |
| static inline unsigned int crypto_skcipher_alignmask( |
| struct crypto_skcipher *tfm) |
| { |
| return crypto_tfm_alg_alignmask(crypto_skcipher_tfm(tfm)); |
| } |
| |
| static inline u32 crypto_skcipher_get_flags(struct crypto_skcipher *tfm) |
| { |
| return crypto_tfm_get_flags(crypto_skcipher_tfm(tfm)); |
| } |
| |
| static inline void crypto_skcipher_set_flags(struct crypto_skcipher *tfm, |
| u32 flags) |
| { |
| crypto_tfm_set_flags(crypto_skcipher_tfm(tfm), flags); |
| } |
| |
| static inline void crypto_skcipher_clear_flags(struct crypto_skcipher *tfm, |
| u32 flags) |
| { |
| crypto_tfm_clear_flags(crypto_skcipher_tfm(tfm), flags); |
| } |
| |
| static inline u32 crypto_sync_skcipher_get_flags( |
| struct crypto_sync_skcipher *tfm) |
| { |
| return crypto_skcipher_get_flags(&tfm->base); |
| } |
| |
| static inline void crypto_sync_skcipher_set_flags( |
| struct crypto_sync_skcipher *tfm, u32 flags) |
| { |
| crypto_skcipher_set_flags(&tfm->base, flags); |
| } |
| |
| static inline void crypto_sync_skcipher_clear_flags( |
| struct crypto_sync_skcipher *tfm, u32 flags) |
| { |
| crypto_skcipher_clear_flags(&tfm->base, flags); |
| } |
| |
| /** |
| * crypto_skcipher_setkey() - set key for cipher |
| * @tfm: cipher handle |
| * @key: buffer holding the key |
| * @keylen: length of the key in bytes |
| * |
| * The caller provided key is set for the skcipher referenced by the cipher |
| * handle. |
| * |
| * Note, the key length determines the cipher type. Many block ciphers implement |
| * different cipher modes depending on the key size, such as AES-128 vs AES-192 |
| * vs. AES-256. When providing a 16 byte key for an AES cipher handle, AES-128 |
| * is performed. |
| * |
| * Return: 0 if the setting of the key was successful; < 0 if an error occurred |
| */ |
| static inline int crypto_skcipher_setkey(struct crypto_skcipher *tfm, |
| const u8 *key, unsigned int keylen) |
| { |
| return tfm->setkey(tfm, key, keylen); |
| } |
| |
| static inline int crypto_sync_skcipher_setkey(struct crypto_sync_skcipher *tfm, |
| const u8 *key, unsigned int keylen) |
| { |
| return crypto_skcipher_setkey(&tfm->base, key, keylen); |
| } |
| |
| static inline unsigned int crypto_skcipher_default_keysize( |
| struct crypto_skcipher *tfm) |
| { |
| return tfm->keysize; |
| } |
| |
| /** |
| * crypto_skcipher_reqtfm() - obtain cipher handle from request |
| * @req: skcipher_request out of which the cipher handle is to be obtained |
| * |
| * Return the crypto_skcipher handle when furnishing an skcipher_request |
| * data structure. |
| * |
| * Return: crypto_skcipher handle |
| */ |
| static inline struct crypto_skcipher *crypto_skcipher_reqtfm( |
| struct skcipher_request *req) |
| { |
| return __crypto_skcipher_cast(req->base.tfm); |
| } |
| |
| static inline struct crypto_sync_skcipher *crypto_sync_skcipher_reqtfm( |
| struct skcipher_request *req) |
| { |
| struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); |
| |
| return container_of(tfm, struct crypto_sync_skcipher, base); |
| } |
| |
| /** |
| * crypto_skcipher_encrypt() - encrypt plaintext |
| * @req: reference to the skcipher_request handle that holds all information |
| * needed to perform the cipher operation |
| * |
| * Encrypt plaintext data using the skcipher_request handle. That data |
| * structure and how it is filled with data is discussed with the |
| * skcipher_request_* functions. |
| * |
| * Return: 0 if the cipher operation was successful; < 0 if an error occurred |
| */ |
| int crypto_skcipher_encrypt(struct skcipher_request *req); |
| |
| /** |
| * crypto_skcipher_decrypt() - decrypt ciphertext |
| * @req: reference to the skcipher_request handle that holds all information |
| * needed to perform the cipher operation |
| * |
| * Decrypt ciphertext data using the skcipher_request handle. That data |
| * structure and how it is filled with data is discussed with the |
| * skcipher_request_* functions. |
| * |
| * Return: 0 if the cipher operation was successful; < 0 if an error occurred |
| */ |
| int crypto_skcipher_decrypt(struct skcipher_request *req); |
| |
| /** |
| * DOC: Symmetric Key Cipher Request Handle |
| * |
| * The skcipher_request data structure contains all pointers to data |
| * required for the symmetric key cipher operation. This includes the cipher |
| * handle (which can be used by multiple skcipher_request instances), pointer |
| * to plaintext and ciphertext, asynchronous callback function, etc. It acts |
| * as a handle to the skcipher_request_* API calls in a similar way as |
| * skcipher handle to the crypto_skcipher_* API calls. |
| */ |
| |
| /** |
| * crypto_skcipher_reqsize() - obtain size of the request data structure |
| * @tfm: cipher handle |
| * |
| * Return: number of bytes |
| */ |
| static inline unsigned int crypto_skcipher_reqsize(struct crypto_skcipher *tfm) |
| { |
| return tfm->reqsize; |
| } |
| |
| /** |
| * skcipher_request_set_tfm() - update cipher handle reference in request |
| * @req: request handle to be modified |
| * @tfm: cipher handle that shall be added to the request handle |
| * |
| * Allow the caller to replace the existing skcipher handle in the request |
| * data structure with a different one. |
| */ |
| static inline void skcipher_request_set_tfm(struct skcipher_request *req, |
| struct crypto_skcipher *tfm) |
| { |
| req->base.tfm = crypto_skcipher_tfm(tfm); |
| } |
| |
| static inline void skcipher_request_set_sync_tfm(struct skcipher_request *req, |
| struct crypto_sync_skcipher *tfm) |
| { |
| skcipher_request_set_tfm(req, &tfm->base); |
| } |
| |
| static inline struct skcipher_request *skcipher_request_cast( |
| struct crypto_async_request *req) |
| { |
| return container_of(req, struct skcipher_request, base); |
| } |
| |
| /** |
| * skcipher_request_alloc() - allocate request data structure |
| * @tfm: cipher handle to be registered with the request |
| * @gfp: memory allocation flag that is handed to kmalloc by the API call. |
| * |
| * Allocate the request data structure that must be used with the skcipher |
| * encrypt and decrypt API calls. During the allocation, the provided skcipher |
| * handle is registered in the request data structure. |
| * |
| * Return: allocated request handle in case of success, or NULL if out of memory |
| */ |
| static inline struct skcipher_request *skcipher_request_alloc( |
| struct crypto_skcipher *tfm, gfp_t gfp) |
| { |
| struct skcipher_request *req; |
| |
| req = kmalloc(sizeof(struct skcipher_request) + |
| crypto_skcipher_reqsize(tfm), gfp); |
| |
| if (likely(req)) |
| skcipher_request_set_tfm(req, tfm); |
| |
| return req; |
| } |
| |
| /** |
| * skcipher_request_free() - zeroize and free request data structure |
| * @req: request data structure cipher handle to be freed |
| */ |
| static inline void skcipher_request_free(struct skcipher_request *req) |
| { |
| kzfree(req); |
| } |
| |
| static inline void skcipher_request_zero(struct skcipher_request *req) |
| { |
| struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); |
| |
| memzero_explicit(req, sizeof(*req) + crypto_skcipher_reqsize(tfm)); |
| } |
| |
| /** |
| * skcipher_request_set_callback() - set asynchronous callback function |
| * @req: request handle |
| * @flags: specify zero or an ORing of the flags |
| * CRYPTO_TFM_REQ_MAY_BACKLOG the request queue may back log and |
| * increase the wait queue beyond the initial maximum size; |
| * CRYPTO_TFM_REQ_MAY_SLEEP the request processing may sleep |
| * @compl: callback function pointer to be registered with the request handle |
| * @data: The data pointer refers to memory that is not used by the kernel |
| * crypto API, but provided to the callback function for it to use. Here, |
| * the caller can provide a reference to memory the callback function can |
| * operate on. As the callback function is invoked asynchronously to the |
| * related functionality, it may need to access data structures of the |
| * related functionality which can be referenced using this pointer. The |
| * callback function can access the memory via the "data" field in the |
| * crypto_async_request data structure provided to the callback function. |
| * |
| * This function allows setting the callback function that is triggered once the |
| * cipher operation completes. |
| * |
| * The callback function is registered with the skcipher_request handle and |
| * must comply with the following template:: |
| * |
| * void callback_function(struct crypto_async_request *req, int error) |
| */ |
| static inline void skcipher_request_set_callback(struct skcipher_request *req, |
| u32 flags, |
| crypto_completion_t compl, |
| void *data) |
| { |
| req->base.complete = compl; |
| req->base.data = data; |
| req->base.flags = flags; |
| } |
| |
| /** |
| * skcipher_request_set_crypt() - set data buffers |
| * @req: request handle |
| * @src: source scatter / gather list |
| * @dst: destination scatter / gather list |
| * @cryptlen: number of bytes to process from @src |
| * @iv: IV for the cipher operation which must comply with the IV size defined |
| * by crypto_skcipher_ivsize |
| * |
| * This function allows setting of the source data and destination data |
| * scatter / gather lists. |
| * |
| * For encryption, the source is treated as the plaintext and the |
| * destination is the ciphertext. For a decryption operation, the use is |
| * reversed - the source is the ciphertext and the destination is the plaintext. |
| */ |
| static inline void skcipher_request_set_crypt( |
| struct skcipher_request *req, |
| struct scatterlist *src, struct scatterlist *dst, |
| unsigned int cryptlen, void *iv) |
| { |
| req->src = src; |
| req->dst = dst; |
| req->cryptlen = cryptlen; |
| req->iv = iv; |
| } |
| |
| #endif /* _CRYPTO_SKCIPHER_H */ |
| |