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2012-10-14Merge branch 'modules-next' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux Pull module signing support from Rusty Russell: "module signing is the highlight, but it's an all-over David Howells frenzy..." Hmm "Magrathea: Glacier signing key". Somebody has been reading too much HHGTTG. * 'modules-next' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (37 commits) X.509: Fix indefinite length element skip error handling X.509: Convert some printk calls to pr_devel asymmetric keys: fix printk format warning MODSIGN: Fix 32-bit overflow in X.509 certificate validity date checking MODSIGN: Make mrproper should remove generated files. MODSIGN: Use utf8 strings in signer's name in autogenerated X.509 certs MODSIGN: Use the same digest for the autogen key sig as for the module sig MODSIGN: Sign modules during the build process MODSIGN: Provide a script for generating a key ID from an X.509 cert MODSIGN: Implement module signature checking MODSIGN: Provide module signing public keys to the kernel MODSIGN: Automatically generate module signing keys if missing MODSIGN: Provide Kconfig options MODSIGN: Provide gitignore and make clean rules for extra files MODSIGN: Add FIPS policy module: signature checking hook X.509: Add a crypto key parser for binary (DER) X.509 certificates MPILIB: Provide a function to read raw data into an MPI X.509: Add an ASN.1 decoder X.509: Add simple ASN.1 grammar compiler ...
2012-10-08KEYS: Implement asymmetric key typeDavid Howells1-0/+1
Create a key type that can be used to represent an asymmetric key type for use in appropriate cryptographic operations, such as encryption, decryption, signature generation and signature verification. The key type is "asymmetric" and can provide access to a variety of cryptographic algorithms. Possibly, this would be better as "public_key" - but that has the disadvantage that "public key" is an overloaded term. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-08-01powerpc/crypto: add 842 crypto driverSeth Jennings1-0/+1
This patch add the 842 cryptographic API driver that submits compression requests to the 842 hardware compression accelerator driver (nx-compress). If the hardware accelerator goes offline for any reason (dynamic disable, migration, etc...), this driver will use LZO as a software failover for all future compression requests. For decompression requests, the 842 hardware driver contains a software implementation of the 842 decompressor to support the decompression of data that was compressed before the accelerator went offline. Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com> Signed-off-by: Seth Jennings <sjenning@linux.vnet.ibm.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2012-08-01crypto: cast6 - prepare generic module for optimized implementationsJohannes Goetzfried1-1/+1
Rename cast6 module to cast6_generic to allow autoloading of optimized implementations. Generic functions and s-boxes are exported to be able to use them within optimized implementations. Signed-off-by: Johannes Goetzfried <Johannes.Goetzfried@informatik.stud.uni-erlangen.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2012-08-01crypto: cast5 - prepare generic module for optimized implementationsJohannes Goetzfried1-1/+1
Rename cast5 module to cast5_generic to allow autoloading of optimized implementations. Generic functions and s-boxes are exported to be able to use them within optimized implementations. Signed-off-by: Johannes Goetzfried <Johannes.Goetzfried@informatik.stud.uni-erlangen.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2012-03-14crypto: camellia - rename camellia.c to camellia_generic.cJussi Kivilinna1-1/+0
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2012-03-14crypto: camellia - rename camellia module to camellia_genericJussi Kivilinna1-1/+2
Rename camellia module to camellia_generic to allow optimized assembler implementations to autoload with module-alias. Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2011-11-30crypto: serpent - rename serpent.c to serpent_generic.cJussi Kivilinna1-2/+0
Now that serpent.c has been cleaned from checkpatch warnings, we can do clean rename. Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2011-11-09crypto: serpent - rename module from serpent to serpent_genericJussi Kivilinna1-1/+3
Rename module from serpent.ko to serpent_generic.ko and add module alias. This is to allow assembler implementation to autoload on 'modprobe serpent'. Also add driver_name and priority for serpent cipher. CC: Dag Arne Osvik <osvik@ii.uib.no> Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2011-10-21crypto: Add userspace configuration APISteffen Klassert1-0/+1
This patch adds a basic userspace configuration API for the crypto layer. With this it is possible to instantiate, remove and to show crypto algorithms from userspace. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2011-09-22crypto: blowfish - rename C-version to blowfish_genericJussi Kivilinna1-1/+1
Rename blowfish to blowfish_generic so that assembler versions of blowfish cipher can autoload. Module alias 'blowfish' is added. Also fix checkpatch warnings. Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2011-09-22crypto: blowfish - split generic and common c codeJussi Kivilinna1-0/+1
Patch splits up the blowfish crypto routine into a common part (key setup) which will be used by blowfish crypto modules (x86_64 assembly and generic-c). Also fixes errors/warnings reported by checkpatch. Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2011-03-13crypto: authencesn - Add algorithm to handle IPsec extended sequence numbersSteffen Klassert1-1/+1
ESP with separate encryption/authentication algorithms needs a special treatment for the associated data. This patch add a new algorithm that handles esp with extended sequence numbers. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-11-27crypto: Makefile clean upTracey Dent1-7/+7
Changed Makefile to use <modules>-y instead of <modules>-objs. Signed-off-by: Tracey Dent <tdent48227@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-11-26crypto: algif_skcipher - User-space interface for skcipher operationsHerbert Xu1-0/+1
This patch adds the af_alg plugin for symmetric key ciphers, corresponding to the ablkcipher kernel operation type. Keys can optionally be set through the setsockopt interface. Once a sendmsg call occurs without MSG_MORE no further writes may be made to the socket until all previous data has been read. IVs and and whether encryption/decryption is performed can be set through the setsockopt interface or as a control message to sendmsg. The interface is completely synchronous, all operations are carried out in recvmsg(2) and will complete prior to the system call returning. The splice(2) interface support reading the user-space data directly without copying (except that the Crypto API itself may copy the data if alignment is off). The recvmsg(2) interface supports directly writing to user-space without additional copying, i.e., the kernel crypto interface will receive the user-space address as its output SG list. Thakns to Miloslav Trmac for reviewing this and contributing fixes and improvements. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Acked-by: David S. Miller <davem@davemloft.net>
2010-11-19crypto: algif_hash - User-space interface for hash operationsHerbert Xu1-0/+1
This patch adds the af_alg plugin for hash, corresponding to the ahash kernel operation type. Keys can optionally be set through the setsockopt interface. Each sendmsg call will finalise the hash unless sent with a MSG_MORE flag. Partial hash states can be cloned using accept(2). The interface is completely synchronous, all operations will complete prior to the system call returning. Both sendmsg(2) and splice(2) support reading the user-space data directly without copying (except that the Crypto API itself may copy the data if alignment is off). For now only the splice(2) interface supports performing digest instead of init/update/final. In future the sendmsg(2) interface will also be modified to use digest/finup where possible so that hardware that cannot return a partial hash state can still benefit from this interface. Thakns to Miloslav Trmac for reviewing this and contributing fixes and improvements. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Acked-by: David S. Miller <davem@davemloft.net> Tested-by: Martin Willi <martin@strongswan.org>
2010-11-19crypto: af_alg - User-space interface for Crypto APIHerbert Xu1-0/+1
This patch creates the backbone of the user-space interface for the Crypto API, through a new socket family AF_ALG. Each session corresponds to one or more connections obtained from that socket. The number depends on the number of inputs/outputs of that particular type of operation. For most types there will be a s ingle connection/file descriptor that is used for both input and output. AEAD is one of the few that require two inputs. Each algorithm type will provide its own implementation that plugs into af_alg. They're keyed using a string such as "skcipher" or "hash". IOW this patch only contains the boring bits that is required to hold everything together. Thakns to Miloslav Trmac for reviewing this and contributing fixes and improvements. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Acked-by: David S. Miller <davem@davemloft.net> Tested-by: Martin Willi <martin@strongswan.org>
2010-06-03crypto: twofish: Rename twofish to twofish_generic and add an aliasJoachim Fritschi1-1/+1
This fixes the broken autoloading of the corresponding twofish assembler ciphers on x86 and x86_64 if they are available. The module name of the generic implementation was in conflict with the alias in the assembler modules. The generic twofish c implementation is renamed to twofish_generic according to the other algorithms with assembler implementations and an module alias is added for 'twofish'. You can now load 'twofish' giving you the best implementation by priority, 'twofish-generic' to get the c implementation or 'twofish-asm' to get the assembler version of cipher. Signed-off-by: Joachim Fritschi <jfritschi@freenet.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-06-03crypto: pcomp - Fix illegal Kconfig configurationHerbert Xu1-1/+1
The PCOMP Kconfig entry current allows the following combination which is illegal: ZLIB=y PCOMP=y ALGAPI=m ALGAPI2=y MANAGER=m MANAGER2=m This patch fixes this by adding PCOMP2 so that PCOMP can select ALGAPI to propagate the setting to MANAGER2. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-01-07crypto: pcrypt - Add pcrypt crypto parallelization wrapperSteffen Klassert1-0/+1
This patch adds a parallel crypto template that takes a crypto algorithm and converts it to process the crypto transforms in parallel. For the moment only aead algorithms are supported. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-09-02crypto: vmac - New hash algorithm for intel_txt supportShane Wang1-0/+1
This patch adds VMAC (a fast MAC) support into crypto framework. Signed-off-by: Shane Wang <shane.wang@intel.com> Signed-off-by: Joseph Cihula <joseph.cihula@intel.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-08-06crypto: ghash - Add GHASH digest algorithm for GCMHuang Ying1-0/+1
GHASH is implemented as a shash algorithm. The actual implementation is copied from gcm.c. This makes it possible to add architecture/hardware accelerated GHASH implementation. Signed-off-by: Huang Ying <ying.huang@intel.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-07-14crypto: hash - Remove legacy hash/digest implementaionHerbert Xu1-2/+1
This patch removes the implementation of hash and digest now that no algorithms use them anymore. The interface though will remain until the users are converted across. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-03-04crypto: zlib - New zlib crypto module, using pcompGeert Uytterhoeven1-0/+1
Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com> Cc: James Morris <jmorris@namei.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-03-04crypto: compress - Add pcomp interfaceGeert Uytterhoeven1-0/+2
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>
2009-02-19crypto: api - Use dedicated workqueue for crypto subsystemHuang Ying1-0/+2
Use dedicated workqueue for crypto subsystem A dedicated workqueue named kcrypto_wq is created to be used by crypto subsystem. The system shared keventd_wq is not suitable for encryption/decryption, because of potential starvation problem. Signed-off-by: Huang Ying <ying.huang@intel.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-12-25crypto: hash - Add shash interfaceHerbert Xu1-0/+1
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>
2008-12-10crypto: api - Disallow cryptomgr as a module if algorithms are built-inHerbert Xu1-9/+9
If we have at least one algorithm built-in then it no longer makes sense to have the testing framework, and hence cryptomgr to be a module. It should be either on or off, i.e., built-in or disabled. This just happens to stop a potential runaway modprobe loop that seems to trigger on at least one distro. With fixes from Evgeniy Polyakov. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-08-29crypto: rng - RNG interface and implementationNeil Horman1-1/+3
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>
2008-08-29crypto: api - Add fips_enable flagNeil Horman1-0/+2
Add the ability to turn FIPS-compliant mode on or off at boot In order to be FIPS compliant, several check may need to be preformed that may be construed as unusefull in a non-compliant mode. This patch allows us to set a kernel flag incating that we are running in a fips-compliant mode from boot up. It also exports that mode information to user space via a sysctl (/proc/sys/crypto/fips_enabled). Tested successfully by me. Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-08-29crypto: skcipher - Move IV generators into their own modulesHerbert Xu1-2/+2
This patch moves the default IV generators into their own modules in order to break a dependency loop between cryptomgr, rng, and blkcipher. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-08-29crypto: cryptomgr - Add test infrastructureHerbert Xu1-0/+2
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>
2008-07-15Revert crypto: prng - Deterministic CPRNGHerbert Xu1-1/+1
This patch is clearly not ready yet for prime time. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-07-10crypto: prng - Deterministic CPRNGNeil Horman1-1/+1
This patch adds a cryptographic pseudo-random number generator based on CTR(AES-128). 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>
2008-07-10[CRYPTO] hash: Add asynchronous hash supportLoc Ho1-0/+1
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>
2008-07-10[CRYPTO] ripemd: Add support for RIPEMD-256 and RIPEMD-320Adrian-Ken Rueegsegger1-0/+2
This patch adds support for the extended RIPEMD hash algorithms RIPEMD-256 and RIPEMD-320. Signed-off-by: Adrian-Ken Rueegsegger <rueegsegger@swiss-it.ch> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-07-10[CRYPTO] ripemd: Add support for RIPEMD hash algorithmsAdrian-Ken Rueegsegger1-0/+2
This patch adds support for RIPEMD-128 and RIPEMD-160 hash algorithms. Signed-off-by: Adrian-Ken Rueegsegger <rueegsegger@swiss-it.ch> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-04-21[CRYPTO] api: Make the crypto subsystem fully modularSebastian Siewior1-1/+2
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-04-21[CRYPTO] cts: Add CTS mode required for Kerberos AES supportKevin Coffman1-0/+1
Implement CTS wrapper for CBC mode required for support of AES encryption support for Kerberos (rfc3962). Signed-off-by: Kevin Coffman <kwc@citi.umich.edu> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-04-21[CRYPTO] sha512: Rename sha512 to sha512_genericJan Glauber1-1/+1
Rename sha512 to sha512_generic and add a MODULE_ALIAS for sha512 so all sha512 implementations can be loaded automatically. Keep the broken tabs so git recognizes this as a rename. Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-02-23[CRYPTO] skcipher: Move chainiv/seqiv into crypto_blkcipher moduleHerbert Xu1-2/+2
For compatibility with dm-crypt initramfs setups it is useful to merge chainiv/seqiv into the crypto_blkcipher module. Since they're required by most algorithms anyway this is an acceptable trade-off. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11[CRYPTO] ccm: Added CCM modeJoy Latten1-0/+1
This patch adds Counter with CBC-MAC (CCM) support. RFC 3610 and NIST Special Publication 800-38C were referenced. Signed-off-by: Joy Latten <latten@austin.ibm.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11[CRYPTO] seqiv: Add Sequence Number IV GeneratorHerbert Xu1-0/+1
This generator generates an IV based on a sequence number by xoring it with a salt. This algorithm is mainly useful for CTR and similar modes. This patch also sets it as the default IV generator for ctr. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11[CRYPTO] eseqiv: Add Encrypted Sequence Number IV GeneratorHerbert Xu1-0/+1
This generator generates an IV based on a sequence number by xoring it with a salt and then encrypting it with the same key as used to encrypt the plain text. This algorithm requires that the block size be equal to the IV size. It is mainly useful for CBC. It has one noteworthy property that for IPsec the IV happens to lie just before the plain text so the IV generation simply increases the number of encrypted blocks by one. Therefore the cost of this generator is entirely dependent on the speed of the underlying cipher. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11[CRYPTO] chainiv: Add chain IV generatorHerbert Xu1-0/+1
The chain IV generator is the one we've been using in the IPsec stack. It simply starts out with a random IV, then uses the last block of each encrypted packet's cipher text as the IV for the next packet. It can only be used by synchronous ciphers since we have to make sure that we don't start the encryption of the next packet until the last one has completed. It does have the advantage of using very little CPU time since it doesn't have to generate anything at all. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11[CRYPTO] blkcipher: Merge ablkcipher and blkcipher into one option/moduleHerbert Xu1-2/+4
With the impending addition of the givcipher type, both blkcipher and ablkcipher algorithms will use it to create givcipher objects. As such it no longer makes sense to split the system between ablkcipher and blkcipher. In particular, both ablkcipher.c and blkcipher.c would need to use the givcipher type which has to reside in ablkcipher.c since it shares much code with it. This patch merges the two Kconfig options as well as the modules into one. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11[CRYPTO] lzo: Add LZO compression algorithm supportZoltan Sogor1-0/+1
Add LZO compression algorithm support Signed-off-by: Zoltan Sogor <weth@inf.u-szeged.hu> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11[CRYPTO] gcm: New algorithmMikko Herranen1-0/+1
Add GCM/GMAC support to cryptoapi. GCM (Galois/Counter Mode) is an AEAD mode of operations for any block cipher with a block size of 16. The typical example is AES-GCM. Signed-off-by: Mikko Herranen <mh1@iki.fi> Reviewed-by: Mika Kukkonen <mika.kukkonen@nsn.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11[CRYPTO] salsa20: Salsa20 stream cipherTan Swee Heng1-0/+1
This patch implements the Salsa20 stream cipher using the blkcipher interface. The core cipher code comes from Daniel Bernstein's submission to eSTREAM: http://www.ecrypt.eu.org/stream/svn/viewcvs.cgi/ecrypt/trunk/submissions/salsa20/full/ref/ The test vectors comes from: http://www.ecrypt.eu.org/stream/svn/viewcvs.cgi/ecrypt/trunk/submissions/salsa20/full/ It has been tested successfully with "modprobe tcrypt mode=34" on an UML instance. Signed-off-by: Tan Swee Heng <thesweeheng@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11[CRYPTO] ctr: Add CTR (Counter) block cipher modeJoy Latten1-0/+1
This patch implements CTR mode for IPsec. It is based off of RFC 3686. Please note: 1. CTR turns a block cipher into a stream cipher. Encryption is done in blocks, however the last block may be a partial block. A "counter block" is encrypted, creating a keystream that is xor'ed with the plaintext. The counter portion of the counter block is incremented after each block of plaintext is encrypted. Decryption is performed in same manner. 2. The CTR counterblock is composed of, nonce + IV + counter The size of the counterblock is equivalent to the blocksize of the cipher. sizeof(nonce) + sizeof(IV) + sizeof(counter) = blocksize The CTR template requires the name of the cipher algorithm, the sizeof the nonce, and the sizeof the iv. ctr(cipher,sizeof_nonce,sizeof_iv) So for example, ctr(aes,4,8) specifies the counterblock will be composed of 4 bytes from a nonce, 8 bytes from the iv, and 4 bytes for counter since aes has a blocksize of 16 bytes. 3. The counter portion of the counter block is stored in big endian for conformance to rfc 3686. Signed-off-by: Joy Latten <latten@austin.ibm.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>