Remove casting the values returned by dma_alloc_coherent.
Signed-off-by: Xu Wang <vulab@iscas.ac.cn>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
'pci_set_dma_mask()' + 'pci_set_consistent_dma_mask()' can be replaced by
an equivalent 'dma_set_mask_and_coherent()' which is much less verbose.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
'pci_set_dma_mask()' + 'pci_set_consistent_dma_mask()' can be replaced by
an equivalent 'dma_set_mask_and_coherent()' which is much less verbose.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Currently <crypto/sha.h> contains declarations for both SHA-1 and SHA-2,
and <crypto/sha3.h> contains declarations for SHA-3.
This organization is inconsistent, but more importantly SHA-1 is no
longer considered to be cryptographically secure. So to the extent
possible, SHA-1 shouldn't be grouped together with any of the other SHA
versions, and usage of it should be phased out.
Therefore, split <crypto/sha.h> into two headers <crypto/sha1.h> and
<crypto/sha2.h>, and make everyone explicitly specify whether they want
the declarations for SHA-1, SHA-2, or both.
This avoids making the SHA-1 declarations visible to files that don't
want anything to do with SHA-1. It also prepares for potentially moving
sha1.h into a new insecure/ or dangerous/ directory.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch fixes all the sparse warnings in cavium/nitrox:
- Fix endianness warnings by adding the correct markers to unions.
- Add missing header inclusions for prototypes.
- Move nitrox_sriov_configure prototype into the isr header file.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Pull crypto updates from Herbert Xu:
"API:
- Allow DRBG testing through user-space af_alg
- Add tcrypt speed testing support for keyed hashes
- Add type-safe init/exit hooks for ahash
Algorithms:
- Mark arc4 as obsolete and pending for future removal
- Mark anubis, khazad, sead and tea as obsolete
- Improve boot-time xor benchmark
- Add OSCCA SM2 asymmetric cipher algorithm and use it for integrity
Drivers:
- Fixes and enhancement for XTS in caam
- Add support for XIP8001B hwrng in xiphera-trng
- Add RNG and hash support in sun8i-ce/sun8i-ss
- Allow imx-rngc to be used by kernel entropy pool
- Use crypto engine in omap-sham
- Add support for Ingenic X1830 with ingenic"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (205 commits)
X.509: Fix modular build of public_key_sm2
crypto: xor - Remove unused variable count in do_xor_speed
X.509: fix error return value on the failed path
crypto: bcm - Verify GCM/CCM key length in setkey
crypto: qat - drop input parameter from adf_enable_aer()
crypto: qat - fix function parameters descriptions
crypto: atmel-tdes - use semicolons rather than commas to separate statements
crypto: drivers - use semicolons rather than commas to separate statements
hwrng: mxc-rnga - use semicolons rather than commas to separate statements
hwrng: iproc-rng200 - use semicolons rather than commas to separate statements
hwrng: stm32 - use semicolons rather than commas to separate statements
crypto: xor - use ktime for template benchmarking
crypto: xor - defer load time benchmark to a later time
crypto: hisilicon/zip - fix the uninitalized 'curr_qm_qp_num'
crypto: hisilicon/zip - fix the return value when device is busy
crypto: hisilicon/zip - fix zero length input in GZIP decompress
crypto: hisilicon/zip - fix the uncleared debug registers
lib/mpi: Fix unused variable warnings
crypto: x86/poly1305 - Remove assignments with no effect
hwrng: npcm - modify readl to readb
...
Use DEFINE_SHOW_ATTRIBUTE macro to simplify the code.
Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Provide an error message for users when pci_request_mem_regions failed.
Signed-off-by: George Acosta <acostag.ubuntu@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
As said by Linus:
A symmetric naming is only helpful if it implies symmetries in use.
Otherwise it's actively misleading.
In "kzalloc()", the z is meaningful and an important part of what the
caller wants.
In "kzfree()", the z is actively detrimental, because maybe in the
future we really _might_ want to use that "memfill(0xdeadbeef)" or
something. The "zero" part of the interface isn't even _relevant_.
The main reason that kzfree() exists is to clear sensitive information
that should not be leaked to other future users of the same memory
objects.
Rename kzfree() to kfree_sensitive() to follow the example of the recently
added kvfree_sensitive() and make the intention of the API more explicit.
In addition, memzero_explicit() is used to clear the memory to make sure
that it won't get optimized away by the compiler.
The renaming is done by using the command sequence:
git grep -w --name-only kzfree |\
xargs sed -i 's/kzfree/kfree_sensitive/'
followed by some editing of the kfree_sensitive() kerneldoc and adding
a kzfree backward compatibility macro in slab.h.
[akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h]
[akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more]
Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Joe Perches <joe@perches.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "Jason A . Donenfeld" <Jason@zx2c4.com>
Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch fixes all the sparse warnings in the octeontx driver.
Some of these are just trivial type changes.
However, some of the changes are non-trivial on little-endian hosts.
Obviously the driver appears to be broken on either LE or BE as it
was doing different things. I've taken the BE behaviour as the
correct one.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
There is this call chain:
cvm_encrypt -> cvm_enc_dec -> cptvf_do_request -> process_request -> kzalloc
where we call sleeping allocator function even if CRYPTO_TFM_REQ_MAY_SLEEP
was not specified.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org # v4.11+
Fixes: c694b23329 ("crypto: cavium - Add the Virtual Function driver for CPT")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
When a list is completely iterated with 'list_for_each_entry(x, ...)', x is
not NULL at the end.
While at it, remove a useless initialization of the ndev variable. It
is overridden by 'list_for_each_entry'.
Fixes: f2663872f0 ("crypto: cavium - Register the CNN55XX supported crypto algorithms.")
Cc: <stable@vger.kernel.org>
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The CRYPTO_TFM_RES_BAD_KEY_LEN flag was apparently meant as a way to
make the ->setkey() functions provide more information about errors.
However, no one actually checks for this flag, which makes it pointless.
Also, many algorithms fail to set this flag when given a bad length key.
Reviewing just the generic implementations, this is the case for
aes-fixed-time, cbcmac, echainiv, nhpoly1305, pcrypt, rfc3686, rfc4309,
rfc7539, rfc7539esp, salsa20, seqiv, and xcbc. But there are probably
many more in arch/*/crypto/ and drivers/crypto/.
Some algorithms can even set this flag when the key is the correct
length. For example, authenc and authencesn set it when the key payload
is malformed in any way (not just a bad length), the atmel-sha and ccree
drivers can set it if a memory allocation fails, and the chelsio driver
sets it for bad auth tag lengths, not just bad key lengths.
So even if someone actually wanted to start checking this flag (which
seems unlikely, since it's been unused for a long time), there would be
a lot of work needed to get it working correctly. But it would probably
be much better to go back to the drawing board and just define different
return values, like -EINVAL if the key is invalid for the algorithm vs.
-EKEYREJECTED if the key was rejected by a policy like "no weak keys".
That would be much simpler, less error-prone, and easier to test.
So just remove this flag.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Commit 7a7ffe65c8 ("crypto: skcipher - Add top-level skcipher interface")
dated 20 august 2015 introduced the new skcipher API which is supposed to
replace both blkcipher and ablkcipher. While all consumers of the API have
been converted long ago, some producers of the ablkcipher remain, forcing
us to keep the ablkcipher support routines alive, along with the matching
code to expose [a]blkciphers via the skcipher API.
So switch this driver to the skcipher API, allowing us to finally drop the
ablkcipher code in the near future.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Setting the cra_type field is not necessary for skciphers, and ablkcipher
will be removed, so drop the assignment from the nitrox driver.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Now that the blkcipher algorithm type has been removed in favor of
skcipher, rename the crypto_blkcipher kernel module to crypto_skcipher,
and rename the config options accordingly:
CONFIG_CRYPTO_BLKCIPHER => CONFIG_CRYPTO_SKCIPHER
CONFIG_CRYPTO_BLKCIPHER2 => CONFIG_CRYPTO_SKCIPHER2
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Add support to get microcode information in VF from PF via mailbox
message.
Signed-off-by: Nagadheeraj Rottela <rnagadheeraj@marvell.com>
Reviewed-by: Srikanth Jampala <jsrikanth@marvell.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Self test failures are due to wrong output IV. This patch fixes this
issue by copying back output IV into skcipher request.
Signed-off-by: Nagadheeraj Rottela <rnagadheeraj@marvell.com>
Reviewed-by: Srikanth Jampala <jsrikanth@marvell.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Check if device supports assoclen to solve hung task timeout error when
extra tests are enabled. Return -EINVAL if assoclen is not supported.
Check authsize to return -EINVAL if authentication tag size is invalid.
Change blocksize to 1 to match with generic implementation.
Signed-off-by: Nagadheeraj Rottela <rnagadheeraj@marvell.com>
Reported-by: Mallesham Jatharakonda <mallesham.jatharakonda@oneconvergence.com>
Suggested-by: Mallesham Jatharakonda <mallesham.jatharakonda@oneconvergence.com>
Reviewed-by: Srikanth Jampala <jsrikanth@marvell.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
When using single_open() for opening, single_release() should be
used instead of seq_release(), otherwise there is a memory leak.
Fixes: 09ae5d37e0 ("crypto: zip - Add Compression/Decompression statistics")
Cc: <stable@vger.kernel.org>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Another one for the cipher museum: split off DES core processing into
a separate module so other drivers (mostly for crypto accelerators)
can reuse the code without pulling in the generic DES cipher itself.
This will also permit the cipher interface to be made private to the
crypto API itself once we move the only user in the kernel (CIFS) to
this library interface.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds support to load Asymmetric crypto firmware on
AE cores of CNN55XX device. Firmware is stored on UCD block 2
and all available AE cores are tagged to group 0.
Signed-off-by: Phani Kiran Hemadri <phemadri@marvell.com>
Reviewed-by: Srikanth Jampala <jsrikanth@marvell.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Pull crypto updates from Herbert Xu:
"Here is the crypto update for 5.3:
API:
- Test shash interface directly in testmgr
- cra_driver_name is now mandatory
Algorithms:
- Replace arc4 crypto_cipher with library helper
- Implement 5 way interleave for ECB, CBC and CTR on arm64
- Add xxhash
- Add continuous self-test on noise source to drbg
- Update jitter RNG
Drivers:
- Add support for SHA204A random number generator
- Add support for 7211 in iproc-rng200
- Fix fuzz test failures in inside-secure
- Fix fuzz test failures in talitos
- Fix fuzz test failures in qat"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (143 commits)
crypto: stm32/hash - remove interruptible condition for dma
crypto: stm32/hash - Fix hmac issue more than 256 bytes
crypto: stm32/crc32 - rename driver file
crypto: amcc - remove memset after dma_alloc_coherent
crypto: ccp - Switch to SPDX license identifiers
crypto: ccp - Validate the the error value used to index error messages
crypto: doc - Fix formatting of new crypto engine content
crypto: doc - Add parameter documentation
crypto: arm64/aes-ce - implement 5 way interleave for ECB, CBC and CTR
crypto: arm64/aes-ce - add 5 way interleave routines
crypto: talitos - drop icv_ool
crypto: talitos - fix hash on SEC1.
crypto: talitos - move struct talitos_edesc into talitos.h
lib/scatterlist: Fix mapping iterator when sg->offset is greater than PAGE_SIZE
crypto/NX: Set receive window credits to max number of CRBs in RxFIFO
crypto: asymmetric_keys - select CRYPTO_HASH where needed
crypto: serpent - mark __serpent_setkey_sbox noinline
crypto: testmgr - dynamically allocate crypto_shash
crypto: testmgr - dynamically allocate testvec_config
crypto: talitos - eliminate unneeded 'done' functions at build time
...
This patch corrects the SPDX License Identifier style
in header files related to Crypto Drivers for Cavium Nitrox
family CNN55XX devices.
For C header files Documentation/process/license-rules.rst
mandates C-like comments (opposed to C source files where
C++ style should be used)
Changes made by using a script provided by Joe Perches here:
https://lkml.org/lkml/2019/2/7/46
Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Nishad Kamdar <nishadkamdar@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of version 2 of the gnu general public license as
published by the free software foundation
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 107 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190528171438.615055994@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
kcrypto_wq is only used by cryptd, so move it into cryptd.c and change
the workqueue name from "crypto" to "cryptd".
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Add SPDX license identifiers to all Make/Kconfig files which:
- Have no license information of any form
These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:
GPL-2.0-only
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add SPDX license identifiers to all files which:
- Have no license information of any form
- Have MODULE_LICENCE("GPL*") inside which was used in the initial
scan/conversion to ignore the file
These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:
GPL-2.0-only
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull crypto update from Herbert Xu:
"API:
- Add support for AEAD in simd
- Add fuzz testing to testmgr
- Add panic_on_fail module parameter to testmgr
- Use per-CPU struct instead multiple variables in scompress
- Change verify API for akcipher
Algorithms:
- Convert x86 AEAD algorithms over to simd
- Forbid 2-key 3DES in FIPS mode
- Add EC-RDSA (GOST 34.10) algorithm
Drivers:
- Set output IV with ctr-aes in crypto4xx
- Set output IV in rockchip
- Fix potential length overflow with hashing in sun4i-ss
- Fix computation error with ctr in vmx
- Add SM4 protected keys support in ccree
- Remove long-broken mxc-scc driver
- Add rfc4106(gcm(aes)) cipher support in cavium/nitrox"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (179 commits)
crypto: ccree - use a proper le32 type for le32 val
crypto: ccree - remove set but not used variable 'du_size'
crypto: ccree - Make cc_sec_disable static
crypto: ccree - fix spelling mistake "protedcted" -> "protected"
crypto: caam/qi2 - generate hash keys in-place
crypto: caam/qi2 - fix DMA mapping of stack memory
crypto: caam/qi2 - fix zero-length buffer DMA mapping
crypto: stm32/cryp - update to return iv_out
crypto: stm32/cryp - remove request mutex protection
crypto: stm32/cryp - add weak key check for DES
crypto: atmel - remove set but not used variable 'alg_name'
crypto: picoxcell - Use dev_get_drvdata()
crypto: crypto4xx - get rid of redundant using_sd variable
crypto: crypto4xx - use sync skcipher for fallback
crypto: crypto4xx - fix cfb and ofb "overran dst buffer" issues
crypto: crypto4xx - fix ctr-aes missing output IV
crypto: ecrdsa - select ASN1 and OID_REGISTRY for EC-RDSA
crypto: ux500 - use ccflags-y instead of CFLAGS_<basename>.o
crypto: ccree - handle tee fips error during power management resume
crypto: ccree - add function to handle cryptocell tee fips error
...
This patch fixes the NITROX-V family part name format. The fix includes
ZIP core performance (feature option) in the part name to differentiate
various HW devices. The complete HW part name format is mentioned below
Part name: CNN55<core option>-<freq>BG676-<feature option>-<rev>
Signed-off-by: Nagadheeraj Rottela <rnagadheeraj@marvell.com>
Reviewed-by: Srikanth Jampala <jsrikanth@marvell.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The cavium crypto driver adds 'sizeof(struct ablkcipher_request)' to its
request size because "the cryptd daemon uses this memory for request_ctx
information". This is incorrect and unnecessary; cryptd doesn't require
wrapped algorithms to reserve extra request space. So remove this.
Also remove the unneeded memset() of the tfm context to 0.
It's already zeroed on allocation.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
mmiowb() is now implied by spin_unlock() on architectures that require
it, so there is no reason to call it from driver code. This patch was
generated using coccinelle:
@mmiowb@
@@
- mmiowb();
and invoked as:
$ for d in drivers include/linux/qed sound; do \
spatch --include-headers --sp-file mmiowb.cocci --dir $d --in-place; done
NOTE: mmiowb() has only ever guaranteed ordering in conjunction with
spin_unlock(). However, pairing each mmiowb() removal in this patch with
the corresponding call to spin_unlock() is not at all trivial, so there
is a small chance that this change may regress any drivers incorrectly
relying on mmiowb() to order MMIO writes between CPUs using lock-free
synchronisation. If you've ended up bisecting to this commit, you can
reintroduce the mmiowb() calls using wmb() instead, which should restore
the old behaviour on all architectures other than some esoteric ia64
systems.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Fix sparse warning:
drivers/crypto/cavium/cpt/cptvf_main.c:644:6:
warning: symbol 'cptvf_device_init' was not declared. Should it be static?
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Fix following sparse warnings:
drivers/crypto/cavium/zip/zip_crypto.c:72:5: warning: symbol 'zip_ctx_init' was not declared. Should it be static?
drivers/crypto/cavium/zip/zip_crypto.c:110:6: warning: symbol 'zip_ctx_exit' was not declared. Should it be static?
drivers/crypto/cavium/zip/zip_crypto.c:122:5: warning: symbol 'zip_compress' was not declared. Should it be static?
drivers/crypto/cavium/zip/zip_crypto.c:158:5: warning: symbol 'zip_decompress' was not declared. Should it be static?
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Fix sparse warnings:
drivers/crypto/cavium/cpt/cptvf_reqmanager.c:226:5: warning: symbol 'send_cpt_command' was not declared. Should it be static?
drivers/crypto/cavium/cpt/cptvf_reqmanager.c:273:6: warning: symbol 'do_request_cleanup' was not declared. Should it be static?
drivers/crypto/cavium/cpt/cptvf_reqmanager.c:319:6: warning: symbol 'do_post_process' was not declared. Should it be static?
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>