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path: root/include/linux/crypto.h
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* crypto: compress - Add pcomp interfaceGeert Uytterhoeven2009-03-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current "comp" crypto interface supports one-shot (de)compression only, i.e. the whole data buffer to be (de)compressed must be passed at once, and the whole (de)compressed data buffer will be received at once. In several use-cases (e.g. compressed file systems that store files in big compressed blocks), this workflow is not suitable. Furthermore, the "comp" type doesn't provide for the configuration of (de)compression parameters, and always allocates workspace memory for both compression and decompression, which may waste memory. To solve this, add a "pcomp" partial (de)compression interface that provides the following operations: - crypto_compress_{init,update,final}() for compression, - crypto_decompress_{init,update,final}() for decompression, - crypto_{,de}compress_setup(), to configure (de)compression parameters (incl. allocating workspace memory). The (de)compression methods take a struct comp_request, which was mimicked after the z_stream object in zlib, and contains buffer pointer and length pairs for input and output. The setup methods take an opaque parameter pointer and length pair. Parameters are supposed to be encoded using netlink attributes, whose meanings depend on the actual (name of the) (de)compression algorithm. Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: api - Fix crypto_alloc_tfm/create_create_tfm return conventionHerbert Xu2009-02-18
| | | | | | | | | | | | | | | | | | | | | | | | This is based on a report and patch by Geert Uytterhoeven. The functions crypto_alloc_tfm and create_create_tfm return a pointer that needs to be adjusted by the caller when successful and otherwise an error value. This means that the caller has to check for the error and only perform the adjustment if the pointer returned is valid. Since all callers want to make the adjustment and we know how to adjust it ourselves, it's much easier to just return adjusted pointer directly. The only caveat is that we have to return a void * instead of struct crypto_tfm *. However, this isn't that bad because both of these functions are for internal use only (by types code like shash.c, not even algorithms code). This patch also moves crypto_alloc_tfm into crypto/internal.h (crypto_create_tfm is already there) to reflect this. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: api - Fix zeroing on freeHerbert Xu2009-02-05
| | | | | | | | | Geert Uytterhoeven pointed out that we're not zeroing all the memory when freeing a transform. This patch fixes it by calling ksize to ensure that we zero everything in sight. Reported-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: hash - Export shash through hashHerbert Xu2008-12-24
| | | | | | | | This patch allows shash algorithms to be used through the old hash interface. This is a transitional measure so we can convert the underlying algorithms to shash before converting the users across. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: hash - Add import/export interfaceHerbert Xu2008-12-24
| | | | | | | | | | | | It is often useful to save the partial state of a hash function so that it can be used as a base for two or more computations. The most prominent example is HMAC where all hashes start from a base determined by the key. Having an import/export interface means that we only have to compute that base once rather than for each message. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: hash - Export shash through ahashHerbert Xu2008-12-24
| | | | | | | | This patch allows shash algorithms to be used through the ahash interface. This is required before we can convert digest algorithms over to shash. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: hash - Add shash interfaceHerbert Xu2008-12-24
| | | | | | | | | | | | | | | | | | | | | | | | The shash interface replaces the current synchronous hash interface. It improves over hash in two ways. Firstly shash is reentrant, meaning that the same tfm may be used by two threads simultaneously as all hashing state is stored in a local descriptor. The other enhancement is that shash no longer takes scatter list entries. This is because shash is specifically designed for synchronous algorithms and as such scatter lists are unnecessary. All existing hash users will be converted to shash once the algorithms have been completely converted. There is also a new finup function that combines update with final. This will be extended to ahash once the algorithm conversion is done. This is also the first time that an algorithm type has their own registration function. Existing algorithm types will be converted to this way in due course. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: api - Rebirth of crypto_alloc_tfmHerbert Xu2008-12-24
| | | | | | | | | | | | | | | This patch reintroduces a completely revamped crypto_alloc_tfm. The biggest change is that we now take two crypto_type objects when allocating a tfm, a frontend and a backend. In fact this simply formalises what we've been doing behind the API's back. For example, as it stands crypto_alloc_ahash may use an actual ahash algorithm or a crypto_hash algorithm. Putting this in the API allows us to do this much more cleanly. The existing types will be converted across gradually. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: api - Move type exit function into crypto_tfmHerbert Xu2008-12-24
| | | | | | | | | | | | | | | | | | | | | | | The type exit function needs to undo any allocations done by the type init function. However, the type init function may differ depending on the upper-level type of the transform (e.g., a crypto_blkcipher instantiated as a crypto_ablkcipher). So we need to move the exit function out of the lower-level structure and into crypto_tfm itself. As it stands this is a no-op since nobody uses exit functions at all. However, all cases where a lower-level type is instantiated as a different upper-level type (such as blkcipher as ablkcipher) will be converted such that they allocate the underlying transform and use that instead of casting (e.g., crypto_ablkcipher casted into crypto_blkcipher). That will need to use a different exit function depending on the upper-level type. This patch also allows the type init/exit functions to call (or not) cra_init/cra_exit instead of always calling them from the top level. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: rng - RNG interface and implementationNeil Horman2008-08-29
| | | | | | | | | | | | This patch adds a random number generator interface as well as a cryptographic pseudo-random number generator based on AES. It is meant to be used in cases where a deterministic CPRNG is required. One of the first applications will be as an input in the IPsec IV generation process. Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: api - Use test infrastructureHerbert Xu2008-08-29
| | | | | | | | This patch makes use of the new testing infrastructure by requiring algorithms to pass a run-time test before they're made available to users. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: cryptomgr - Add test infrastructureHerbert Xu2008-08-29
| | | | | | | | This patch moves the newly created alg_test infrastructure into cryptomgr. This shall allow us to use it for testing at algorithm registrations. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: hash - Move ahash functions into crypto/hash.hHerbert Xu2008-07-10
| | | | | | | | | | | All new crypto interfaces should go into individual files as much as possible in order to ensure that crypto.h does not collapse under its own weight. This patch moves the ahash code into crypto/hash.h and crypto/internal/hash.h respectively. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: hash - Removed vestigial ahash fieldsHerbert Xu2008-07-10
| | | | | | | | | The base field in ahash_tfm appears to have been cut-n-pasted from ablkcipher. It isn't needed here at all. Similarly, the info field in ahash_request also appears to have originated from its cipher counter-part and is vestigial. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] hash: Add asynchronous hash supportLoc Ho2008-07-10
| | | | | | | This patch adds asynchronous hash and digest support. Signed-off-by: Loc Ho <lho@amcc.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] api: Make the crypto subsystem fully modularSebastian Siewior2008-04-20
| | | | | Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] api: Set default CRYPTO_MINALIGN to unsigned long longHerbert Xu2008-01-10
| | | | | | | | | | | Thanks to David Miller for pointing out that the SLAB (or SLOB/SLUB) cache uses the alignment of unsigned long long if the architecture kmalloc/slab alignment macros are not defined. This patch changes the CRYPTO_MINALIGN so that it uses the same default value. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] aead: Create default givcipher instancesHerbert Xu2008-01-10
| | | | | | | | | This patch makes crypto_alloc_aead always return algorithms that is capable of generating their own IVs through givencrypt and givdecrypt. All existing AEAD algorithms already do. New ones must either supply their own or specify a generic IV generator with the geniv field. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] aead: Add aead_geniv_alloc/aead_geniv_freeHerbert Xu2008-01-10
| | | | | | | | | This patch creates the infrastructure to help the construction of IV generator templates that wrap around AEAD algorithms by adding an IV generator to them. This is useful for AEAD algorithms with no built-in IV generator or to replace their built-in generator. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] aead: Add givcrypt operationsHerbert Xu2008-01-10
| | | | | | | | | | | | | | | | | | | | This patch adds the underlying givcrypt operations for aead and associated support elements. The rationale is identical to that of the skcipher givcrypt operations, i.e., sometimes only the algorithm knows how the IV should be generated. A new request type aead_givcrypt_request is added which contains an embedded aead_request structure with two new elements to support this operation. The new elements are seq and giv. The seq field should contain a strictly increasing 64-bit integer which may be used by certain IV generators as an input value. The giv field will be used to store the generated IV. It does not need to obey the alignment requirements of the algorithm because it's not used during the operation. The existing iv field must still be available as it will be used to store intermediate IVs and the output IV if chaining is desired. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] skcipher: Create default givcipher instancesHerbert Xu2008-01-10
| | | | | | | | | | | | | | | This patch makes crypto_alloc_ablkcipher/crypto_grab_skcipher always return algorithms that are capable of generating their own IVs through givencrypt and givdecrypt. Each algorithm may specify its default IV generator through the geniv field. For algorithms that do not set the geniv field, the blkcipher layer will pick a default. Currently it's chainiv for synchronous algorithms and eseqiv for asynchronous algorithms. Note that if these wrappers do not work on an algorithm then that algorithm must specify its own geniv or it can't be used at all. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] skcipher: Add skcipher_geniv_alloc/skcipher_geniv_freeHerbert Xu2008-01-10
| | | | | | | | This patch creates the infrastructure to help the construction of givcipher templates that wrap around existing blkcipher/ablkcipher algorithms by adding an IV generator to them. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] skcipher: Added geniv fieldHerbert Xu2008-01-10
| | | | | | | | This patch introduces the geniv field which indicates the default IV generator for each algorithm. It should point to a string that is not freed as long as the algorithm is registered. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] skcipher: Add givcrypt operations and givcipher typeHerbert Xu2008-01-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Different block cipher modes have different requirements for intialisation vectors. For example, CBC can use a simple randomly generated IV while modes such as CTR must use an IV generation mechanisms that give a stronger guarantee on the lack of collisions. Furthermore, disk encryption modes have their own IV generation algorithms. Up until now IV generation has been left to the users of the symmetric key cipher API. This is inconvenient as the number of block cipher modes increase because the user needs to be aware of which mode is supposed to be paired with which IV generation algorithm. Therefore it makes sense to integrate the IV generation into the crypto API. This patch takes the first step in that direction by creating two new ablkcipher operations, givencrypt and givdecrypt that generates an IV before performing the actual encryption or decryption. The operations are currently not exposed to the user. That will be done once the underlying functionality has actually been implemented. It also creates the underlying givcipher type. Algorithms that directly generate IVs would use it instead of ablkcipher. All other algorithms (including all existing ones) would generate a givcipher algorithm upon registration. This givcipher algorithm will be constructed from the geniv string that's stored in every algorithm. That string will locate a template which is instantiated by the blkcipher/ablkcipher algorithm in question to give a givcipher algorithm. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] skcipher: Add crypto_grab_skcipher interfaceHerbert Xu2008-01-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Note: From now on the collective of ablkcipher/blkcipher/givcipher will be known as skcipher, i.e., symmetric key cipher. The name blkcipher has always been much of a misnomer since it supports stream ciphers too. This patch adds the function crypto_grab_skcipher as a new way of getting an ablkcipher spawn. The problem is that previously we did this in two steps, first getting the algorithm and then calling crypto_init_spawn. This meant that each spawn user had to be aware of what type and mask to use for these two steps. This is difficult and also presents a problem when the type/mask changes as they're about to be for IV generators. The new interface does both steps together just like crypto_alloc_ablkcipher. As a side-effect this also allows us to be stronger on type enforcement for spawns. For now this is only done for ablkcipher but it's trivial to extend for other types. This patch also moves the type/mask logic for skcipher into the helpers crypto_skcipher_type and crypto_skcipher_mask. Finally this patch introduces the function crypto_require_sync to determine whether the user is specifically requesting a sync algorithm. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] api: Sanitise mask when allocating ablkcipher/hashHerbert Xu2008-01-10
| | | | | | | | | When allocating ablkcipher/hash objects, we use a mask that's wider than the usual type mask. This patch sanitises the mask supplied by the user so we don't end up using a narrower mask which may lead to unintended results. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] aead: Make authsize a run-time parameterHerbert Xu2008-01-10
| | | | | | | | | | | | | | | As it is authsize is an algorithm paramter which cannot be changed at run-time. This is inconvenient because hardware that implements such algorithms would have to register each authsize that they support separately. Since authsize is a property common to all AEAD algorithms, we can add a function setauthsize that sets it at run-time, just like setkey. This patch does exactly that and also changes authenc so that authsize is no longer a parameter of its template. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] ablkcipher: Add distinct ABLKCIPHER typeHerbert Xu2008-01-10
| | | | | | | | | | | | | | | | | | | | | | | | Up until now we have ablkcipher algorithms have been identified as type BLKCIPHER with the ASYNC bit set. This is suboptimal because ablkcipher refers to two things. On the one hand it refers to the top-level ablkcipher interface with requests. On the other hand it refers to and algorithm type underneath. As it is you cannot request a synchronous block cipher algorithm with the ablkcipher interface on top. This is a problem because we want to be able to eventually phase out the blkcipher top-level interface. This patch fixes this by making ABLKCIPHER its own type, just as we have distinct types for HASH and DIGEST. The type it associated with the algorithm implementation only. Which top-level interface is used for synchronous block ciphers is then determined by the mask that's used. If it's a specific mask then the old blkcipher interface is given, otherwise we go with the new ablkcipher interface. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: convert crypto.h to UTF-8John Anthony Kazos Jr2007-10-19
| | | | | | | Convert the encoding of <include/linux/crypto.h> from ISO-8859-1 to UTF-8. Signed-off-by: John Anthony Kazos Jr. <jakj@j-a-k-j.com> Signed-off-by: Adrian Bunk <bunk@kernel.org>
* [CRYPTO] api: Fixed crypto_*_reqsize return typeHerbert Xu2007-10-10
| | | | | | | | This patch changes the return type of crypto_*_reqsize from int to unsigned int which matches what the underlying type is (and should be). Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] ablkcipher: Remove queue pointer from common alg objectHerbert Xu2007-10-10
| | | | | | | | Since not everyone needs a queue pointer and those who need it can always get it from the context anyway the queue pointer in the common alg object is redundant. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] api: Add support for multiple template parametersHerbert Xu2007-10-10
| | | | | | | | | | | | | | This patch adds support for having multiple parameters to a template, separated by a comma. It also adds support for integer parameters in addition to the current algorithm parameter type. This will be used by the authenc template which will have four parameters: the authentication algorithm, the encryption algorithm, the authentication size and the encryption key length. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] api: Add aead crypto typeHerbert Xu2007-10-10
| | | | | | | | | | | | | | | | | This patch adds crypto_aead which is the interface for AEAD (Authenticated Encryption with Associated Data) algorithms. AEAD algorithms perform authentication and encryption in one step. Traditionally users (such as IPsec) would use two different crypto algorithms to perform these. With AEAD this comes down to one algorithm and one operation. Of course if traditional algorithms were used we'd still be doing two operations underneath. However, real AEAD algorithms may allow the underlying operations to be optimised as well. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] cipher: Remove obsolete fields from cipher_tfmHerbert Xu2007-07-11
| | | | | | This removes all the unused block cipher fields from cipher_tfm. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] api: Add ablkcipher_request_set_tfmHerbert Xu2007-05-02
| | | | | | | This patch adds ablkcipher_request_set_tfm for those users that need to manage the memory for ablkcipher requests directly. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] api: Add async blkcipher typeHerbert Xu2007-05-02
| | | | | | | | This patch adds the mid-level interface for asynchronous block ciphers. It also includes a generic queueing mechanism that can be used by other asynchronous crypto operations in future. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] templates: Pass type/mask when creating instancesHerbert Xu2007-05-02
| | | | | | | | | | | | | This patch passes the type/mask along when constructing instances of templates. This is in preparation for templates that may support multiple types of instances depending on what is requested. For example, the planned software async crypto driver will use this construct. For the moment this allows us to check whether the instance constructed is of the correct type and avoid returning success if the type does not match. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] api: Add async block cipher interfaceHerbert Xu2007-05-02
| | | | | | | | | | | | | | | | This patch adds the frontend interface for asynchronous block ciphers. In addition to the usual block cipher parameters, there is a callback function pointer and a data pointer. The callback will be invoked only if the encrypt/decrypt handlers return -EINPROGRESS. In other words, if the return value of zero the completion handler (or the equivalent code) needs to be invoked by the caller. The request structure is allocated and freed by the caller. Its size is determined by calling crypto_ablkcipher_reqsize(). The helpers ablkcipher_request_alloc/ablkcipher_request_free can be used to manage the memory for a request. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] api: Use structs for cipher/compressionHerbert Xu2007-02-06
| | | | | | | | Now that all cipher/compression users have switched over to the new allocation scheme, we can get rid of the compatility defines and use proper structs for them. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] api: Remove deprecated interfaceHerbert Xu2007-02-06
| | | | | | This patch removes the old cipher interface and related code. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] api: Remove unused functionsAdrian Bunk2006-12-06
| | | | | | | | | | | | This patch removes the following no longer used functions: - api.c: crypto_alg_available() - digest.c: crypto_digest_init() - digest.c: crypto_digest_update() - digest.c: crypto_digest_final() - digest.c: crypto_digest_digest() Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] api: Remove one too many semicolonYoichi Yuasa2006-11-19
| | | | | | | This patch has removed one too many semicolon in crypto.h. Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] api: Deprecate crypto_digest_* and crypto_alg_availableHerbert Xu2006-09-20
| | | | | | | | This patch marks the crypto_digest_* functions and crypto_alg_available as deprecated. They've been replaced by crypto_hash_* and crypto_has_* respectively. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] padlock: Convert padlock-sha to use crypto_hashHerbert Xu2006-09-20
| | | | | | | | | | This patch converts padlock-sha to use crypto_hash for its fallback. It also changes the fallback selection to use selection by type instead of name. This is done through the new CRYPTO_ALG_NEED_FALLBACK bit, which is set if and only if an algorithm needs a fallback of the same type. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] users: Use crypto_comp and crypto_has_*Herbert Xu2006-09-20
| | | | | | | This patch converts all users to use the new crypto_comp type and the crypto_has_* functions. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] api: Add crypto_comp and crypto_has_*Herbert Xu2006-09-20
| | | | | | | | This patch adds the crypto_comp type to complete the compile-time checking conversion. The functions crypto_has_alg and crypto_has_cipher, etc. are also added to replace crypto_alg_available. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] digest: Remove old HMAC implementationHerbert Xu2006-09-20
| | | | | | | | This patch removes the old HMAC implementation now that nobody uses it anymore. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
* [CRYPTO] digest: Added user API for new hash typeHerbert Xu2006-09-20
| | | | | | | | | | | | | | | | | The existing digest user interface is inadequate for support asynchronous operations. For one it doesn't return a value to indicate success or failure, nor does it take a per-operation descriptor which is essential for the issuing of requests while other requests are still outstanding. This patch is the first in a series of steps to remodel the interface for asynchronous operations. For the ease of transition the new interface will be known as "hash" while the old one will remain as "digest". This patch also changes sg_next to allow chaining. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] api: Mark parts of cipher interface as deprecatedHerbert Xu2006-09-20
| | | | | | | | Mark the parts of the cipher interface that have been replaced by block ciphers as deprecated. Thanks to Andrew Morton for suggesting doing this before removing them completely. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* [CRYPTO] cipher: Added block cipher typeHerbert Xu2006-09-20
| | | | | | | | | | | | | | | | | | | This patch adds the new type of block ciphers. Unlike current cipher algorithms which operate on a single block at a time, block ciphers operate on an arbitrarily long linear area of data. As it is block-based, it will skip any data remaining at the end which cannot form a block. The block cipher has one major difference when compared to the existing block cipher implementation. The sg walking is now performed by the algorithm rather than the cipher mid-layer. This is needed for drivers that directly support sg lists. It also improves performance for all algorithms as it reduces the total number of indirect calls by one. In future the existing cipher algorithm will be converted to only have a single-block interface. This will be done after all existing users have switched over to the new block cipher type. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>