Add a unit_size field to struct skcipher_request, mirroring the acomp unit_size (and its setter), so a caller can submit several data units in one request: cryptlen / unit_size units sharing one starting IV, with per-unit IVs derived from the IV as a 64-bit little-endian data-unit-number counter held in its low 8 bytes.
unit_size == 0 (the default) means a normal single-unit request; skcipher_request_set_tfm() and the on-stack request initializer zero the field, so existing callers and reused requests are unaffected. Suggested-by: Herbert Xu <[email protected]> Signed-off-by: Leonid Ravich <[email protected]> --- include/crypto/skcipher.h | 46 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 46 insertions(+) diff --git a/include/crypto/skcipher.h b/include/crypto/skcipher.h index 4efe2ca8c4d1..2d7805409140 100644 --- a/include/crypto/skcipher.h +++ b/include/crypto/skcipher.h @@ -31,6 +31,17 @@ struct scatterlist; /** * struct skcipher_request - Symmetric key cipher request * @cryptlen: Number of bytes to encrypt or decrypt + * @unit_size: Size in bytes of each data unit, or 0 for a + * single-unit request (the default). When non-zero, must be a + * multiple of the cipher block size and @cryptlen must be a + * positive multiple of it. The data-unit number is a 64-bit + * little-endian counter in the low 8 bytes of @iv, incremented + * once per unit and wrapping at 2^64; the remaining IV bytes are + * left unchanged (any other on-disk IV layout is produced by a + * template wrapping the algorithm). @iv itself is not modified + * by the request. An algorithm that advertises + * CRYPTO_ALG_REQ_SEG handles the whole request natively and must + * follow this same counter and @iv-preservation convention. * @iv: Initialisation Vector * @src: Source SG list * @dst: Destination SG list @@ -39,6 +50,7 @@ struct scatterlist; */ struct skcipher_request { unsigned int cryptlen; + unsigned int unit_size; u8 *iv; @@ -225,6 +237,7 @@ struct lskcipher_alg { struct skcipher_request *name = \ (((struct skcipher_request *)__##name##_desc)->base.tfm = \ crypto_sync_skcipher_tfm((_tfm)), \ + ((struct skcipher_request *)__##name##_desc)->unit_size = 0, \ (void *)__##name##_desc) /** @@ -819,6 +832,8 @@ static inline void skcipher_request_set_tfm(struct skcipher_request *req, struct crypto_skcipher *tfm) { req->base.tfm = crypto_skcipher_tfm(tfm); + /* New tfm, new request: default to single-unit. */ + req->unit_size = 0; } static inline void skcipher_request_set_sync_tfm(struct skcipher_request *req, @@ -908,6 +923,10 @@ static inline void skcipher_request_set_callback(struct skcipher_request *req, req->base.complete = compl; req->base.data = data; req->base.flags = flags; + /* Reset the per-op multi-unit control; a reused request defaults to + * single-unit until skcipher_request_set_unit_size() opts back in. + */ + req->unit_size = 0; } /** @@ -937,5 +956,32 @@ static inline void skcipher_request_set_crypt( req->iv = iv; } +/** + * skcipher_request_set_unit_size() - submit as multiple data units + * @req: request handle + * @unit_size: unit size in bytes (a multiple of the cipher block size), + * or 0 to disable + * + * Process @req as @cryptlen / @unit_size data units sharing one starting + * @iv, with per-unit IVs derived by treating @iv as a wide counter (the + * data-unit-number convention). @cryptlen must be a positive multiple of + * @unit_size. If the algorithm does not handle multiple units natively, + * the API transparently splits the request into one call per unit; that + * split additionally requires an ivsize that is a non-zero multiple of 8 + * and at most 32 bytes, and rejects a violating request with -EINVAL. An + * algorithm advertising CRYPTO_ALG_REQ_SEG receives the whole request and + * enforces its own constraints. + * + * This function must be called after skcipher_request_set_tfm() and + * skcipher_request_set_callback(), both of which reset @req->unit_size + * to 0. + */ +static inline void +skcipher_request_set_unit_size(struct skcipher_request *req, + unsigned int unit_size) +{ + req->unit_size = unit_size; +} + #endif /* _CRYPTO_SKCIPHER_H */ -- 2.47.3
