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2006-06-26[CRYPTO] tcrypt: Forbid tcrypt from being built-inHerbert Xu1-1/+1
It makes no sense to build tcrypt into the kernel. In fact, now that the driver init function's return status is being checked, it is in fact harmful to do so. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-06-26[CRYPTO] tcrypt: Speed benchmark support for digest algorithmsMichal Ludvig2-0/+206
This patch adds speed tests (benchmarks) for digest algorithms. Tests are run with different buffer sizes (16 bytes, ... 8 kBytes) and with each buffer multiple tests are run with different update() sizes (e.g. hash 64 bytes buffer in four 16 byte updates). There is no correctness checking of the result and all tests and algorithms use the same input buffer. Signed-off-by: Michal Ludvig <michal@logix.cz> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-06-26[CRYPTO] tcrypt: Return -EAGAIN from module_init()Michal Ludvig1-1/+8
Intentionaly return -EAGAIN from module_init() to ensure it doesn't stay loaded in the kernel. The module does all its work from init() and doesn't offer any runtime functionality => we don't need it in the memory, do we? Signed-off-by: Michal Ludvig <michal@logix.cz> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-06-26[CRYPTO] api: Allow replacement when registering new algorithmsHerbert Xu1-2/+2
We already allow asynchronous removal of existing algorithm modules. By allowing the replacement of existing algorithms, we can replace algorithms without having to wait for for all existing users to complete. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-06-26[CRYPTO] api: Removed const from cra_name/cra_driver_nameHerbert Xu1-1/+1
We do need to change these names now and even more so in future with instantiated algorithms. So let's stop lying to the compiler and get rid of the const modifiers. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-06-26[CRYPTO] api: Added cra_init/cra_exitHerbert Xu3-13/+11
This patch adds the hooks cra_init/cra_exit which are called during a tfm's construction and destruction respectively. This will be used by the instances to allocate child tfm's. For now this lets us get rid of the coa_init/coa_exit functions which are used for exactly that purpose (unlike the dia_init function which is called for each transaction). In fact the coa_exit path is currently buggy as it may get called twice when an error is encountered during initialisation. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-06-26[CRYPTO] api: Fixed incorrect passing of context instead of tfmMichal Ludvig2-4/+4
Fix a few omissions in passing TFM instead of CTX to algorithms. Signed-off-by: Michal Ludvig <michal@logix.cz> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-06-26[CRYPTO] all: Pass tfm instead of ctx to algorithmsHerbert Xu25-229/+237
Up until now algorithms have been happy to get a context pointer since they know everything that's in the tfm already (e.g., alignment, block size). However, once we have parameterised algorithms, such information will be specific to each tfm. So the algorithm API needs to be changed to pass the tfm structure instead of the context pointer. This patch is basically a text substitution. The only tricky bit is the assembly routines that need to get the context pointer offset through asm-offsets.h. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-06-26[CRYPTO] digest: Remove unnecessary zeroing during initHerbert Xu3-4/+0
Various digest algorithms operate one block at a time and therefore keep a temporary buffer of partial blocks. This buffer does not need to be initialised since there is a counter which indicates what is and isn't valid in it. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-06-26[CRYPTO] digest: Add alignment handlingAtsushi Nemoto6-15/+35
Some hash modules load/store data words directly. The digest layer should pass properly aligned buffer to update()/final() method. This patch also add cra_alignmask to some hash modules. Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-06-26[CRYPTO] khazad: Use 32-bit reads on keyAtsushi Nemoto1-3/+4
On 64-bit platform, reading 64-bit keys (which is supposed to be 32-bit aligned) at a time will result in unaligned access. Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-03-21[CRYPTO] aes: Fixed array boundary violationDavid McCullough1-4/+3
The AES setkey routine writes 64 bytes to the E_KEY area even though there are only 60 bytes there. It is in fact safe since E_KEY is immediately follwed by D_KEY which is initialised afterwards. However, doing this may trigger undefined behaviour and makes Coverity unhappy. So by combining E_KEY and D_KEY into one array we sidestep this issue altogether. This problem was reported by Adrian Bunk. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-03-21[CRYPTO] tcrypt: Fix key alignmentAtsushi Nemoto1-12/+13
Force 32-bit alignment on keys in tcrypt test vectors. Also rearrange the structure to prevent unnecessary padding. Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-03-21[CRYPTO] all: Add missing cra_alignmaskAtsushi Nemoto2-0/+2
The "des3_ede" and "serpent" lack cra_alignmask. Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-03-21[CRYPTO] all: Use kzalloc where possibleEric Sesterhenn2-5/+2
this patch converts crypto/ to kzalloc usage. Compile tested with allyesconfig. Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-03-21[CRYPTO] api: Align tfm context as wide as possibleHerbert Xu1-1/+1
Since tfm contexts can contain arbitrary types we should provide at least natural alignment (__attribute__ ((__aligned__))) for them. In particular, this is needed on the Xscale which is a 32-bit architecture with a u64 type that requires 64-bit alignment. This problem was reported by Ronen Shitrit. The crypto_tfm structure's size was 44 bytes on 32-bit architectures and 80 bytes on 64-bit architectures. So adding this requirement only means that we have to add an extra 4 bytes on 32-bit architectures. On i386 the natural alignment is 16 bytes which also benefits the VIA Padlock as it no longer has to manually align its context structure to 128 bits. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-03-21[CRYPTO] twofish: Use rol32/ror32 where appropriateDenis Vlasenko1-10/+11
Convert open coded rotations to rol32/ror32. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-02-08[PATCH] remove bogus asm/bug.h includes.Al Viro1-1/+0
A bunch of asm/bug.h includes are both not needed (since it will get pulled anyway) and bogus (since they are done too early). Removed. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2006-01-10[CRYPTO] cipher: Set alignmask for multi-byte loadsHerbert Xu10-0/+12
Many cipher implementations use 4-byte/8-byte loads/stores which require alignment on some architectures. This patch explicitly sets the alignment requirements for them. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-01-10[CRYPTO] api: Require block size to be less than PAGE_SIZE/8Herbert Xu1-1/+1
The cipher code path may allocate up to two blocks of data on the stack. Therefore we need to place limits on the maximum block size. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-01-10[CRYPTO] sha1: Fixed off-by-64 bug in sha1_updateHerbert Xu1-2/+2
After a partial update, the done pointer is off to the right by 64 bytes. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-01-10[CRYPTO] cipher: Align temporary buffer in cbc_process_decryptHerbert Xu1-2/+3
Since the temporary buffer is used as an argument to cia_decrypt, it must be aligned by cra_alignmask. This bug was found by linux@horizon.com. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-01-10[CRYPTO] sha1: Avoid shifting count left and rightNicolas Pitre1-4/+4
This patch avoids shifting the count left and right needlessly for each call to sha1_update(). It instead can be done only once at the end in sha1_final(). Keeping the previous test example (sha1_update() successively called with len=64), a 1.3% performance increase can be observed on i386, or 0.2% on ARM. The generated code is also smaller on ARM. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-01-10[CRYPTO] sha1: Rename i/j to done/partialNicolas Pitre1-11/+12
This patch gives more descriptive names to the variables i and j. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-01-10[CRYPTO] sha1: Avoid useless memcpy()Nicolas Pitre1-8/+17
The current code unconditionally copy the first block for every call to sha1_update(). This can be avoided if there is no pending partial block. This is always the case on the first call to sha1_update() (if the length is >= 64 of course. Furthermore, temp does need to be called if sha_transform is never invoked. Also consolidate the sha_transform calls into one to reduce code size. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-01-10[CRYPTO] Allow AES C/ASM implementations to coexistHerbert Xu2-1/+3
As the Crypto API now allows multiple implementations to be registered for the same algorithm, we no longer have to play tricks with Kconfig to select the right AES implementation. This patch sets the driver name and priority for all the AES implementations and removes the Kconfig conditions on the C implementation for AES. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-01-10[CRYPTO] Allow multiple implementations of the same algorithmHerbert Xu3-9/+55
This is the first step on the road towards asynchronous support in the Crypto API. It adds support for having multiple crypto_alg objects for the same algorithm registered in the system. For example, each device driver would register a crypto_alg object for each algorithm that it supports. While at the same time the user may load software implementations of those same algorithms. Users of the Crypto API may then select a specific implementation by name, or choose any implementation for a given algorithm with the highest priority. The priority field is a 32-bit signed integer. In future it will be possible to modify it from user-space. This also provides a solution to the problem of selecting amongst various AES implementations, that is, aes vs. aes-i586 vs. aes-padlock. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-01-10[CRYPTO] Use standard byte order macros wherever possibleHerbert Xu19-395/+240
A lot of crypto code needs to read/write a 32-bit/64-bit words in a specific gender. Many of them open code them by reading/writing one byte at a time. This patch converts all the applicable usages over to use the standard byte order macros. This is based on a previous patch by Denis Vlasenko. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-01-06[PATCH] s390: cleanup KconfigMartin Schwidefsky1-4/+4
Sanitize some s390 Kconfig options. We have ARCH_S390, ARCH_S390X, ARCH_S390_31, 64BIT, S390_SUPPORT and COMPAT. Replace these 6 options by S390, 64BIT and COMPAT. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06[PATCH] s390: in-kernel crypto test vectorsJan Glauber2-0/+68
Add new test vectors to the AES test suite for AES CBC and AES with plaintext larger than AES blocksize. Signed-off-by: Jan Glauber <jan.glauber@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06[PATCH] s390: aes supportJan Glauber1-0/+20
Add support for the hardware accelerated AES crypto algorithm. Signed-off-by: Jan Glauber <jan.glauber@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06[PATCH] s390: sha256 supportJan Glauber1-0/+11
Add support for the hardware accelerated sha256 crypto algorithm. Signed-off-by: Jan Glauber <jan.glauber@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06[PATCH] s390: in-kernel crypto renameJan Glauber1-4/+4
Replace all references to z990 by s390 in the in-kernel crypto files in arch/s390/crypto. The code is not specific to a particular machine (z990) but to the s390 platform. Big diff, does nothing.. Signed-off-by: Jan Glauber <jan.glauber@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30[CRYPTO] Check cra_alignmask against cra_blocksizeHerbert Xu1-1/+4
The cipher code relies on the fact that the block size is a multiple of the required alignment. So we should check this at the time of algorith registration. We also ensure that the block size is bounded by the page size. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2005-10-30[CRYPTO] Simplify one-member scatterlist expressionsHerbert Xu1-4/+4
This patch rewrites various occurences of &sg[0] where sg is an array of length one to simply sg. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2005-10-30[PATCH] Use sg_set_buf/sg_init_one where applicableDavid Hardeman2-51/+20
This patch uses sg_set_buf/sg_init_one in some places where it was duplicated. Signed-off-by: David Hardeman <david@2gen.com> Cc: James Bottomley <James.Bottomley@steeleye.com> Cc: Greg KH <greg@kroah.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jeff Garzik <jgarzik@pobox.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2005-09-07[CRYPTO] Fix boundary check in standard multi-block cipher processorsHerbert Xu1-3/+9
The boundary check in the standard multi-block cipher processors are broken when nbytes is not a multiple of bsize. In those cases it will always process an extra block. This patch corrects the check so that it processes at most nbytes of data. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-02[CRYPTO]: Added CRYPTO_TFM_REQ_MAY_SLEEP flagHerbert Xu3-6/+4
The crypto layer currently uses in_atomic() to determine whether it is allowed to sleep. This is incorrect since spin locks don't always cause in_atomic() to return true. Instead of that, this patch returns to an earlier idea of a per-tfm flag which determines whether sleeping is allowed. Unlike the earlier version, the default is to not allow sleeping. This ensures that no existing code can break. As usual, this flag may either be set through crypto_alloc_tfm(), or just before a specific crypto operation. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-02[CRYPTO]: Fix XTEA implementationAaron Grothe4-29/+206
The XTEA implementation was incorrect due to a misinterpretation of operator precedence. Because of the wide-spread nature of this error, the erroneous implementation will be kept, albeit under the new name of XETA. Signed-off-by: Aaron Grothe <ajgrothe@yahoo.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-28[PATCH] clean up inline static vs static inlineJesper Juhl1-1/+1
`gcc -W' likes to complain if the static keyword is not at the beginning of the declaration. This patch fixes all remaining occurrences of "inline static" up with "static inline" in the entire kernel tree (140 occurrences in 47 files). While making this change I came across a few lines with trailing whitespace that I also fixed up, I have also added or removed a blank line or two here and there, but there are no functional changes in the patch. Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-15[CRYPTO]: Fix zero-extension bug on 64-bit architectures.Herbert Xu2-4/+4
Noticed by Ken-ichirou MATSUZAWA. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-07[CRYPTO] Add faster DES code from Dag Arne OsvikDag Arne Osvik1-1149/+854
I've made a new implementation of DES to replace the old one in the kernel. It provides faster encryption on all tested processors apart from the original Pentium, and key setup is many times faster. Speed relative to old kernel implementation Processor des_setkey des_encrypt des3_ede_setkey des3_ede_encrypt Pentium 120Mhz 6.8 0.82 7.2 0.86 Pentium III 1.266Ghz 5.6 1.19 5.8 1.34 Pentium M 1.3Ghz 5.7 1.15 6.0 1.31 Pentium 4 2.266Ghz 5.8 1.24 6.0 1.40 Pentium 4E 3Ghz 5.4 1.27 5.5 1.48 StrongARM 1110 206Mhz 4.3 1.03 4.4 1.14 Athlon XP 2Ghz 7.8 1.44 8.1 1.61 Athlon 64 2Ghz 7.8 1.34 8.3 1.49 Signed-off-by: Dag Arne Osvik <da@osvik.no> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-07[CRYPTO] Remove unused iv field from context structureHerbert Xu2-3/+0
The iv field in des_ctx/des3_ede_ctx/serpent_ctx has never been used. This was noticed by Dag Arne Osvik. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-07[CRYPTO] Add x86_64 asm AESAndreas Steinmetz1-1/+21
Implementation: =============== The encrypt/decrypt code is based on an x86 implementation I did a while ago which I never published. This unpublished implementation does include an assembler based key schedule and precomputed tables. For simplicity and best acceptance, however, I took Gladman's in-kernel code for table generation and key schedule for the kernel port of my assembler code and modified this code to produce the key schedule as required by my assembler implementation. File locations and Kconfig are kept similar to the i586 AES assembler implementation. It may seem a little bit strange to use 32 bit I/O and registers in the assembler implementation but this gives the best code size. My implementation takes one instruction more per round compared to Gladman's x86 assembler but it doesn't require any stack for local variables or saved registers and it is less serialized than Gladman's code. Note that all comparisons to Gladman's code were done after my code was implemented. I did only use FIPS PUB 197 for the implementation so my implementation is independent work. If anybody has a better assembler solution for x86_64 I'll be pleased to have my code replaced with the better solution. Testing: ======== The implementation passes the in-kernel crypto testing module and I'm running it without any problems on my laptop where it is mainly used for dm-crypt. Microbenchmark: =============== The microbenchmark was done in userspace with similar compile flags as used during kernel compile. Encrypt/decrypt is about 35% faster than the generic C implementation. As the generic C as well as my assembler implementation are both table I don't really expect that there is much room for further improvements though I'll be glad to be corrected here. The key schedule is about 5% slower than the generic C implementation. This is due to the fact that some more work has to be done in the key schedule routine to fit the schedule to the assembler implementation. Code Size: ========== Encrypt and decrypt are together about 2.1 Kbytes smaller than the generic C implementation which is important with regard to L1 cache usage. The key schedule routine is about 100 bytes larger than the generic C implementation. Data Size: ========== There's no difference in data size requirements between the assembler implementation and the generic C implementation. License: ======== Gladmans's code is dual BSD/GPL whereas my assembler code is GPLv2 only (I'm not going to change the license for my code). So I had to change the module license for the x86_64 aes module from 'Dual BSD/GPL' to 'GPL' to reflect the most restrictive license within the module. Signed-off-by: Andreas Steinmetz <ast@domdv.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-07[CRYPTO] Add null short circuit to crypto_free_tfmJesper Juhl1-2/+10
As far as I'm aware there's a general concensus that functions that are responsible for freeing resources should be able to cope with being passed a NULL pointer. This makes sense as it removes the need for all callers to check for NULL, thus elliminating the bugs that happen when some forget (safer to just check centrally in the freeing function) and it also makes for smaller code all over due to the lack of all those NULL checks. This patch makes it safe to pass the crypto_free_tfm() function a NULL pointer. Once this patch is applied we can start removing the NULL checks from the callers. Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-07[CRYPTO] Handle unaligned iv from encrypt_iv/decrypt_ivHerbert Xu1-2/+27
Even though cit_iv is now always aligned, the user can still supply an unaligned iv through crypto_cipher_encrypt_iv/crypto_cipher_decrypt_iv. This patch will check the alignment of the user-supplied iv and copy it if necessary. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-07[CRYPTO] Ensure cit_iv is aligned correctlyHerbert Xu3-9/+66
This patch ensures that cit_iv is aligned according to cra_alignmask by allocating it as part of the tfm structure. As a side effect the crypto layer will also guarantee that the tfm ctx area has enough space to be aligned by cra_alignmask. This allows us to remove the extra space reservation from the Padlock driver. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-07[CRYPTO] Make crypto_alg_lookup staticAdrian Bunk2-11/+9
This patch makes a needlessly global function static. Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-07[CRYPTO] Add alignmask for low-level cipher implementationsHerbert Xu3-7/+48
The VIA Padlock device requires the input and output buffers to be aligned on 16-byte boundaries. This patch adds the alignmask attribute for low-level cipher implementations to indicate their alignment requirements. The mid-level crypt() function will copy the input/output buffers if they are not aligned correctly before they are passed to the low-level implementation. Strictly speaking, some of the software implementations require the buffers to be aligned on 4-byte boundaries as they do 32-bit loads. However, it is not clear whether it is better to copy the buffers or pay the penalty for unaligned loads/stores. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-07[CRYPTO] Add support for low-level multi-block operationsHerbert Xu2-25/+18
This patch adds hooks for cipher algorithms to implement multi-block ECB/CBC operations directly. This is expected to provide significant performance boots to the VIA Padlock. It could also be used for improving software implementations such as AES where operating on multiple blocks at a time may enable certain optimisations. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>