Commit Graph

101 Commits

Author SHA1 Message Date
Nicolai Stange
462696fd0f lib/mpi: mpi_read_buffer(): fix buffer overflow
Currently, mpi_read_buffer() writes full limbs to the output buffer
and moves memory around to purge leading zero limbs afterwards.

However, with

  commit 9cbe21d8f8 ("lib/mpi: only require buffers as big as needed for
                        the integer")

the caller is only required to provide a buffer large enough to hold the
result without the leading zeros.

This might result in a buffer overflow for small MP numbers with leading
zeros.

Fix this by coping the result to its final destination within the output
buffer and not copying the leading zeros at all.

Fixes: 9cbe21d8f8 ("lib/mpi: only require buffers as big as needed for
                      the integer")
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-04-05 20:35:49 +08:00
Nicolai Stange
90f864e200 lib/mpi: mpi_read_buffer(): replace open coded endian conversion
Currently, the endian conversion from CPU order to BE is open coded in
mpi_read_buffer().

Replace this by the centrally provided cpu_to_be*() macros.
Copy from the temporary storage on stack to the destination buffer
by means of memcpy().

Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-04-05 20:35:49 +08:00
Nicolai Stange
f00fa2417b lib/mpi: mpi_read_buffer(): optimize skipping of leading zero limbs
Currently, if the number of leading zeros is greater than fits into a
complete limb, mpi_read_buffer() skips them by iterating over them
limb-wise.

Instead of skipping the high order zero limbs within the loop as shown
above, adjust the copying loop's bounds.

Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-04-05 20:35:49 +08:00
Nicolai Stange
d755290689 lib/mpi: mpi_write_sgl(): replace open coded endian conversion
Currently, the endian conversion from CPU order to BE is open coded in
mpi_write_sgl().

Replace this by the centrally provided cpu_to_be*() macros.

Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-04-05 20:35:48 +08:00
Nicolai Stange
cece762f6f lib/mpi: mpi_write_sgl(): fix out-of-bounds stack access
Within the copying loop in mpi_write_sgl(), we have

  if (lzeros) {
    mpi_limb_t *limb1 = (void *)p - sizeof(alimb);
    mpi_limb_t *limb2 = (void *)p - sizeof(alimb)
                               + lzeros;
    *limb1 = *limb2;
    ...
  }

where p points past the end of alimb2 which lives on the stack and contains
the current limb in BE order.

The purpose of the above is to shift the non-zero bytes of alimb2 to its
beginning in memory, i.e. to skip its leading zero bytes.

However, limb2 points somewhere into the middle of alimb2 and thus, reading
*limb2 pulls in lzero bytes from somewhere.

Indeed, KASAN splats:

  BUG: KASAN: stack-out-of-bounds in mpi_write_to_sgl+0x4e3/0x6f0
                                      at addr ffff8800cb04f601
  Read of size 8 by task systemd-udevd/391
  page:ffffea00032c13c0 count:0 mapcount:0 mapping:   (null) index:0x0
  flags: 0x3fff8000000000()
  page dumped because: kasan: bad access detected
  CPU: 3 PID: 391 Comm: systemd-udevd Tainted: G  B  L
                                              4.5.0-next-20160316+ #12
  [...]
  Call Trace:
   [<ffffffff8194889e>] dump_stack+0xdc/0x15e
   [<ffffffff819487c2>] ? _atomic_dec_and_lock+0xa2/0xa2
   [<ffffffff814892b5>] ? __dump_page+0x185/0x330
   [<ffffffff8150ffd6>] kasan_report_error+0x5e6/0x8b0
   [<ffffffff814724cd>] ? kzfree+0x2d/0x40
   [<ffffffff819c5bce>] ? mpi_free_limb_space+0xe/0x20
   [<ffffffff819c469e>] ? mpi_powm+0x37e/0x16f0
   [<ffffffff815109f1>] kasan_report+0x71/0xa0
   [<ffffffff819c0353>] ? mpi_write_to_sgl+0x4e3/0x6f0
   [<ffffffff8150ed34>] __asan_load8+0x64/0x70
   [<ffffffff819c0353>] mpi_write_to_sgl+0x4e3/0x6f0
   [<ffffffff819bfe70>] ? mpi_set_buffer+0x620/0x620
   [<ffffffff819c0e6f>] ? mpi_cmp+0xbf/0x180
   [<ffffffff8186e282>] rsa_verify+0x202/0x260

What's more, since lzeros can be anything from 1 to sizeof(mpi_limb_t)-1,
the above will cause unaligned accesses which is bad on non-x86 archs.

Fix the issue, by preparing the starting point p for the upcoming copy
operation instead of shifting the source memory, i.e. alimb2.

Fixes: 2d4d1eea54 ("lib/mpi: Add mpi sgl helpers")
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-04-05 20:35:48 +08:00
Nicolai Stange
ea122be0b8 lib/mpi: mpi_write_sgl(): purge redundant pointer arithmetic
Within the copying loop in mpi_write_sgl(), we have

  if (lzeros) {
    ...
    p -= lzeros;
    y = lzeros;
  }
  p = p - (sizeof(alimb) - y);

If lzeros == 0, then y == 0, too. Thus, lzeros gets subtracted and added
back again to p.

Purge this redundancy.

Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-04-05 20:35:48 +08:00
Nicolai Stange
654842ef53 lib/mpi: mpi_write_sgl(): fix style issue with lzero decrement
Within the copying loop in mpi_write_sgl(), we have

  if (lzeros > 0) {
    ...
    lzeros -= sizeof(alimb);
  }

However, at this point, lzeros < sizeof(alimb) holds. Make this fact
explicit by rewriting the above to

  if (lzeros) {
    ...
    lzeros = 0;
  }

Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-04-05 20:35:46 +08:00
Nicolai Stange
f2d1362ff7 lib/mpi: mpi_write_sgl(): fix skipping of leading zero limbs
Currently, if the number of leading zeros is greater than fits into a
complete limb, mpi_write_sgl() skips them by iterating over them limb-wise.

However, it fails to adjust its internal leading zeros tracking variable,
lzeros, accordingly: it does a

  p -= sizeof(alimb);
  continue;

which should really have been a

  lzeros -= sizeof(alimb);
  continue;

Since lzeros never decreases if its initial value >= sizeof(alimb), nothing
gets copied by mpi_write_sgl() in that case.

Instead of skipping the high order zero limbs within the loop as shown
above, fix the issue by adjusting the copying loop's bounds.

Fixes: 2d4d1eea54 ("lib/mpi: Add mpi sgl helpers")
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-04-05 20:35:46 +08:00
Arnd Bergmann
9c6bd0c2f1 lib/mpi: use "static inline" instead of "extern inline"
When we use CONFIG_PROFILE_ALL_BRANCHES, every 'if()' introduces
a static variable, but that is not allowed in 'extern inline'
functions:

mpi-inline.h:116:204: warning: '______f' is static but declared in inline function 'mpihelp_sub' which is not static
mpi-inline.h:113:184: warning: '______f' is static but declared in inline function 'mpihelp_sub' which is not static
mpi-inline.h:70:184: warning: '______f' is static but declared in inline function 'mpihelp_add' which is not static
mpi-inline.h:56:204: warning: '______f' is static but declared in inline function 'mpihelp_add_1' which is not static

This changes the MPI code to use 'static inline' instead, to get
rid of hundreds of warnings.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-02-28 03:26:34 +08:00
Arnd Bergmann
c5d552487b lib/mpi: avoid assembler warning
A wrapper around the umull assembly instruction might reuse
the input register as an output, which is undefined on
some ARM machines, as pointed out by this assembler warning:

  CC      lib/mpi/generic_mpih-mul1.o
/tmp/ccxJuxIy.s: Assembler messages:
/tmp/ccxJuxIy.s:53: rdhi, rdlo and rm must all be different
  CC      lib/mpi/generic_mpih-mul2.o
/tmp/ccI0scAD.s: Assembler messages:
/tmp/ccI0scAD.s:53: rdhi, rdlo and rm must all be different
  CC      lib/mpi/generic_mpih-mul3.o
/tmp/ccMvVQcp.s: Assembler messages:
/tmp/ccMvVQcp.s:53: rdhi, rdlo and rm must all be different

This changes the constraints to force different registers to
be used as output.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-02-28 03:26:34 +08:00
Michal Marek
3ee0cb5fb5 lib/mpi: Endianness fix
The limbs are integers in the host endianness, so we can't simply
iterate over the individual bytes. The current code happens to work on
little-endian, because the order of the limbs in the MPI array is the
same as the order of the bytes in each limb, but it breaks on
big-endian.

Fixes: 0f74fbf77d ("MPI: Fix mpi_read_buffer")
Signed-off-by: Michal Marek <mmarek@suse.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-02-28 03:26:30 +08:00
Andrzej Zaborowski
9cbe21d8f8 lib/mpi: only require buffers as big as needed for the integer
Since mpi_write_to_sgl and mpi_read_buffer explicitly left-align the
integers being written it makes no sense to require a buffer big enough for
the number + the leading zero bytes which are not written.  The error
returned also doesn't convey any information.  So instead require only the
size needed and return -EOVERFLOW to signal when buffer too short.

Signed-off-by: Andrew Zaborowski <andrew.zaborowski@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-11-17 22:00:39 +08:00
Linus Torvalds
9cf5c095b6 asm-generic cleanups
The asm-generic changes for 4.4 are mostly a series from Christoph Hellwig
 to clean up various abuses of headers in there. The patch to rename the
 io-64-nonatomic-*.h headers caused some conflicts with new users, so I
 added a workaround that we can remove in the next merge window.
 
 The only other patch is a warning fix from Marek Vasut
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Merge tag 'asm-generic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic

Pull asm-generic cleanups from Arnd Bergmann:
 "The asm-generic changes for 4.4 are mostly a series from Christoph
  Hellwig to clean up various abuses of headers in there.  The patch to
  rename the io-64-nonatomic-*.h headers caused some conflicts with new
  users, so I added a workaround that we can remove in the next merge
  window.

  The only other patch is a warning fix from Marek Vasut"

* tag 'asm-generic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
  asm-generic: temporarily add back asm-generic/io-64-nonatomic*.h
  asm-generic: cmpxchg: avoid warnings from macro-ized cmpxchg() implementations
  gpio-mxc: stop including <asm-generic/bug>
  n_tracesink: stop including <asm-generic/bug>
  n_tracerouter: stop including <asm-generic/bug>
  mlx5: stop including <asm-generic/kmap_types.h>
  hifn_795x: stop including <asm-generic/kmap_types.h>
  drbd: stop including <asm-generic/kmap_types.h>
  move count_zeroes.h out of asm-generic
  move io-64-nonatomic*.h out of asm-generic
2015-11-06 14:22:15 -08:00
Stephan Mueller
63349d02c1 lib/mpi: fix off by one in mpi_read_raw_from_sgl
The patch fixes the analysis of the input data which contains an off
by one.

The issue is visible when the SGL contains one byte per SG entry.
The code for checking for zero bytes does not operate on the data byte.

Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-10-20 22:10:47 +08:00
Christoph Hellwig
a1164a3ac7 move count_zeroes.h out of asm-generic
This header contains a few helpers currenly only used by the mpi
implementation, and not default implementation of architecture code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2015-10-15 00:21:07 +02:00
Tadeusz Struk
2d4d1eea54 lib/mpi: Add mpi sgl helpers
Add mpi_read_raw_from_sgl and mpi_write_to_sgl helpers.

Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-10-14 22:23:00 +08:00
Tadeusz Struk
0f74fbf77d MPI: Fix mpi_read_buffer
Change mpi_read_buffer to return a number without leading zeros
so that mpi_read_buffer and mpi_get_buffer return the same thing.

Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-08-25 21:13:16 +08:00
Linus Torvalds
44d21c3f3a Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto update from Herbert Xu:
 "Here is the crypto update for 4.2:

  API:

   - Convert RNG interface to new style.

   - New AEAD interface with one SG list for AD and plain/cipher text.
     All external AEAD users have been converted.

   - New asymmetric key interface (akcipher).

  Algorithms:

   - Chacha20, Poly1305 and RFC7539 support.

   - New RSA implementation.

   - Jitter RNG.

   - DRBG is now seeded with both /dev/random and Jitter RNG.  If kernel
     pool isn't ready then DRBG will be reseeded when it is.

   - DRBG is now the default crypto API RNG, replacing krng.

   - 842 compression (previously part of powerpc nx driver).

  Drivers:

   - Accelerated SHA-512 for arm64.

   - New Marvell CESA driver that supports DMA and more algorithms.

   - Updated powerpc nx 842 support.

   - Added support for SEC1 hardware to talitos"

* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (292 commits)
  crypto: marvell/cesa - remove COMPILE_TEST dependency
  crypto: algif_aead - Temporarily disable all AEAD algorithms
  crypto: af_alg - Forbid the use internal algorithms
  crypto: echainiv - Only hold RNG during initialisation
  crypto: seqiv - Add compatibility support without RNG
  crypto: eseqiv - Offer normal cipher functionality without RNG
  crypto: chainiv - Offer normal cipher functionality without RNG
  crypto: user - Add CRYPTO_MSG_DELRNG
  crypto: user - Move cryptouser.h to uapi
  crypto: rng - Do not free default RNG when it becomes unused
  crypto: skcipher - Allow givencrypt to be NULL
  crypto: sahara - propagate the error on clk_disable_unprepare() failure
  crypto: rsa - fix invalid select for AKCIPHER
  crypto: picoxcell - Update to the current clk API
  crypto: nx - Check for bogus firmware properties
  crypto: marvell/cesa - add DT bindings documentation
  crypto: marvell/cesa - add support for Kirkwood and Dove SoCs
  crypto: marvell/cesa - add support for Orion SoCs
  crypto: marvell/cesa - add allhwsupport module parameter
  crypto: marvell/cesa - add support for all armada SoCs
  ...
2015-06-22 21:04:48 -07:00
Tadeusz Struk
d37e296979 MPILIB: add mpi_read_buf() and mpi_get_size() helpers
Added a mpi_read_buf() helper function to export MPI to a buf provided by
the user, and a mpi_get_size() helper, that tells the user how big the buf is.
Changed mpi_free to use kzfree instead of kfree because it is used to free
crypto keys.

Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-06-16 14:35:06 +08:00
Jaedon Shin
36f5811342 MPI: MIPS: Fix compilation error with GCC 5.1
This patch fixes mips compilation error:

lib/mpi/generic_mpih-mul1.c: In function 'mpihelp_mul_1':
lib/mpi/longlong.h:651:2: error: impossible constraint in 'asm'

Signed-off-by: Jaedon Shin <jaedon.shin@gmail.com>
Cc: Linux-MIPS <linux-mips@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/10546/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-06-13 11:36:41 +02:00
Rasmus Villemoes
b9f918a31d MPILIB: Fix comparison of negative MPIs
If u and v both represent negative integers and their limb counts
happen to differ, mpi_cmp will always return a positive value - this
is obviously bogus. u is smaller than v if and only if it is larger in
absolute value.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Dmitry Kasatkin <dmitry.kasatkin@gmail.com>
2015-01-14 16:10:12 +00:00
Rasmus Villemoes
98dbbcba1b MPILIB: Fix obvious but harmless typo
The macro MPN_COPY_INCR this occurs in isn't used anywhere.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: David Howells <dhowells@redhat.com>
2015-01-14 15:16:00 +00:00
Rasmus Villemoes
7fe21291ba MPILIB: Deobfuscate mpi_cmp
The condition preceding 'return 1;' makes my head hurt. At this point,
we know that u and v have the same sign; if they are negative, they
compare opposite to how their absolute values compare (which
mpihelp_cmp found for us), otherwise cmp itself is the
answer. Negating cmp is ok since mpihelp_cmp returns {-1,0,1};
-INT_MIN==INT_MIN won't bite us.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Dmitry Kasatkin <dmitry.kasatkin@gmail.com>
2015-01-14 15:15:57 +00:00
Konstantin Khlebnikov
4ff1582297 MPILIB: add module description and license
This patch fixes lack of license, otherwise mpi.ko taints kernel.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Signed-off-by: David Howells <dhowells@redhat.com>
2013-09-25 17:17:01 +01:00
Richard Henderson
a5c6eae4d6 alpha: Modernize lib/mpi/longlong.h
Remove the compile warning for __udiv_qrnnd not having a prototype.
Use the __builtin_alpha_umulh introduced in gcc 4.0.

Reviewed-and-Tested-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2013-07-19 13:54:23 -07:00
Chen Gang
5402b8047b lib/mpi/mpicoder.c: looping issue, need stop when equal to zero, found by 'EXTRA_FLAGS=-W'.
For 'while' looping, need stop when 'nbytes == 0', or will cause issue.
('nbytes' is size_t which is always bigger or equal than zero).

The related warning: (with EXTRA_CFLAGS=-W)

  lib/mpi/mpicoder.c:40:2: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits]

Signed-off-by: Chen Gang <gang.chen@asianux.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: David Howells <dhowells@redhat.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-06-12 16:29:44 -07:00
Helge Deller
70ef5578dd MPILIB: disable usage of floating point registers on parisc
The umul_ppmm() macro for parisc uses the xmpyu assembler statement
which does calculation via a floating point register.

But usage of floating point registers inside the Linux kernel are not
allowed and gcc will stop compilation due to the -mdisable-fpregs
compiler option.

Fix this by disabling the umul_ppmm() and udiv_qrnnd() macros. The
mpilib will then use the generic built-in implementations instead.

Signed-off-by: Helge Deller <deller@gmx.de>
2013-05-24 22:30:11 +02:00
Andy Shevchenko
0d2a1b2d03 mpilib: use DIV_ROUND_UP and remove unused macros
Remove MIN, MAX and ABS macros that are duplicates kernel's native
implementation.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2013-02-01 16:28:32 +11:00
Manuel Lauss
a3cea98941 MPI: Fix compilation on MIPS with GCC 4.4 and newer
Since 4.4 GCC on MIPS no longer recognizes the "h" constraint,
leading to this build failure:

  CC      lib/mpi/generic_mpih-mul1.o
lib/mpi/generic_mpih-mul1.c: In function 'mpihelp_mul_1':
lib/mpi/generic_mpih-mul1.c:50:3: error: impossible constraint in 'asm'

This patch updates MPI with the latest umul_ppm implementations for MIPS.

Signed-off-by: Manuel Lauss <manuel.lauss@gmail.com>
Cc: Linux-MIPS <linux-mips@linux-mips.org>
Cc: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Cc: James Morris <jmorris@namei.org>
Patchwork: https://patchwork.linux-mips.org/patch/4612/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-11-23 18:57:17 +01:00
David Howells
e104599294 MPILIB: Provide a function to read raw data into an MPI
Provide a function to read raw data of a predetermined size into an MPI rather
than expecting the size to be encoded within the data.  The data is assumed to
represent an unsigned integer, and the resulting MPI will be positive.

The function looks like this:

	MPI mpi_read_raw_data(const void *, size_t);

This is useful for reading ASN.1 integer primitives where the length is encoded
in the ASN.1 metadata.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-10-08 13:50:21 +10:30
David Howells
12f008b6dc MPILIB: Reinstate mpi_cmp[_ui]() and export for RSA signature verification
Reinstate and export mpi_cmp() and mpi_cmp_ui() from the MPI library for use by
RSA signature verification as per RFC3447 section 5.2.2 step 1.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-10-08 13:50:15 +10:30
David Howells
aacf29bf1b MPILIB: Provide count_leading/trailing_zeros() based on arch functions
Provide count_leading/trailing_zeros() macros based on extant arch bit scanning
functions rather than reimplementing from scratch in MPILIB.

Whilst we're at it, turn count_foo_zeros(n, x) into n = count_foo_zeros(x).

Also move the definition to asm-generic as other people may be interested in
using it.

Signed-off-by: David Howells <dhowells@redhat.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Cc: Arnd Bergmann <arnd@arndb.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-10-08 13:50:11 +10:30
Dmitry Kasatkin
7cf4206a99 Remove unused code from MPI library
MPI library is used by RSA verification implementation.
Few files contains functions which are never called.

James Morris has asked to remove all of them.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Requested-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2012-05-26 11:51:03 +10:00
Dmitry Kasatkin
9e235dcaf4 Revert "crypto: GnuPG based MPI lib - additional sources (part 4)"
This reverts commit 7e8dec918e.

RSA verification implementation does not use this code.
James Morris has asked to remove that.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Requested-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2012-05-26 11:50:44 +10:00
Jesper Juhl
09c79b6096 mpi: Avoid using freed pointer in mpi_lshift_limbs()
At the start of the function we assign 'a->d' to 'ap'. Then we use the
RESIZE_IF_NEEDED macro on 'a' - this may free 'a->d' and replace it
with newly allocaetd storage. In that case, we'll be operating on
freed memory further down in the function when we index into 'ap[]'.
Since we don't actually need 'ap' until after the use of the
RESIZE_IF_NEEDED macro we can just delay the assignment to it until
after we've potentially resized, thus avoiding the issue.

While I was there anyway I also changed the integer variable 'n' to be
const. It might as well be since we only assign to it once and use it
as a constant, and then the compiler will tell us if we ever assign to
it in the future.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Acked-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2012-04-18 12:14:28 +10:00
David Miller
a99e7e5f36 lib: Fix 32-bit sparc udiv_qrnnd() definition in mpilib's longlong.h
This copy of longlong.h is extremely dated and results in compile
errors on sparc32 when MPILIB is enabled, copy over the more uptodate
implementation from arch/sparc/math/sfp-util_32.h

Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: James Morris <jmorris@namei.org>
2012-02-02 10:34:25 +11:00
David Miller
c6df4b17c8 lib: Fix multiple definitions of clz_tab
Both sparc 32-bit's software divide assembler and MPILIB provide
clz_tab[] with identical contents.

Break it out into a seperate object file and select it when
SPARC32 or MPILIB is set.

Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: James Morris <jmorris@namei.org>
2012-02-02 10:34:23 +11:00
Dmitry Kasatkin
43b2c0aeaa lib/mpi: added missing NULL check
Added missing NULL check after mpi_alloc_limb_space().

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Reviewed-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2012-02-02 00:23:39 +11:00
Dmitry Kasatkin
a6d68ecc56 lib/mpi: added comment on divide by 0 case
Comment explains that existing clients do not call this function
with dsize == 0, which means that 1/0 should not happen.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Reviewed-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2012-02-02 00:23:39 +11:00
Dmitry Kasatkin
4877e05619 lib/mpi: check for possible zero length
Buggy client might pass zero nlimbs which is meaningless.
Added check for zero length.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Reviewed-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2012-02-02 00:23:39 +11:00
Dmitry Kasatkin
bc95eeadf5 lib/mpi: removed unused functions
do_encode_md() and mpi_get_keyid() are not parts of mpi library.
They were used early versions of gnupg and in digsig project,
but they are not used neither here nor there anymore.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Reviewed-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2012-02-02 00:23:14 +11:00
Dmitry Kasatkin
e2fe85c236 lib/mpi: checks for zero divisor length
Divisor length should not be 0.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Reviewed-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2012-02-02 00:23:14 +11:00
Dmitry Kasatkin
e87c5e35a9 lib/mpi: return error code on dividing by zero
Definitely better to return error code than to divide by zero.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Reviewed-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2012-02-02 00:23:14 +11:00
Dmitry Kasatkin
3cccd1543a lib/mpi: replaced MPI_NULL with normal NULL
MPI_NULL is replaced with normal NULL.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Reviewed-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2012-02-02 00:23:14 +11:00
Dmitry Kasatkin
c70c471c58 lib/mpi: added missing NULL check
Added missing NULL check after mpi_alloc().

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Reviewed-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2012-02-02 00:23:13 +11:00
David Howells
4bf1924c00 MPILIB: Add a missing ENOMEM check
Add a missing ENOMEM check.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2012-01-19 13:45:51 +11:00
Dan Carpenter
fe0e94c5a7 mpi/mpi-mpow: NULL dereference on allocation failure
We can't call mpi_free() on the elements if the first kzalloc() fails.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-12-08 00:09:23 +11:00
Dmitry Kasatkin
7e8dec918e crypto: GnuPG based MPI lib - additional sources (part 4)
Adds the multi-precision-integer maths library which was originally taken
from GnuPG and ported to the kernel by (among others) David Howells.
This version is taken from Fedora kernel 2.6.32-71.14.1.el6.
The difference is that checkpatch reported errors and warnings have been fixed.

This library is used to implemenet RSA digital signature verification
used in IMA/EVM integrity protection subsystem.

Due to patch size limitation, the patch is divided into 4 parts.

This code is unnecessary for RSA digital signature verification,
but for completeness it is included here and can be compiled,
if CONFIG_MPILIB_EXTRA is enabled.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
2011-11-09 11:47:26 +02:00
Dmitry Kasatkin
d9c46b184f crypto: GnuPG based MPI lib - make files (part 3)
Adds the multi-precision-integer maths library which was originally taken
from GnuPG and ported to the kernel by (among others) David Howells.
This version is taken from Fedora kernel 2.6.32-71.14.1.el6.
The difference is that checkpatch reported errors and warnings have been fixed.

This library is used to implemenet RSA digital signature verification
used in IMA/EVM integrity protection subsystem.

Due to patch size limitation, the patch is divided into 4 parts.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
2011-11-09 11:47:25 +02:00
Dmitry Kasatkin
5ce3e312ec crypto: GnuPG based MPI lib - header files (part 2)
Adds the multi-precision-integer maths library which was originally taken
from GnuPG and ported to the kernel by (among others) David Howells.
This version is taken from Fedora kernel 2.6.32-71.14.1.el6.
The difference is that checkpatch reported errors and warnings have been fixed.

This library is used to implemenet RSA digital signature verification
used in IMA/EVM integrity protection subsystem.

Due to patch size limitation, the patch is divided into 4 parts.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
2011-11-09 11:45:26 +02:00
Dmitry Kasatkin
cdec9cb516 crypto: GnuPG based MPI lib - source files (part 1)
Adds the multi-precision-integer maths library which was originally taken
from GnuPG and ported to the kernel by (among others) David Howells.
This version is taken from Fedora kernel 2.6.32-71.14.1.el6.
The difference is that checkpatch reported errors and warnings have been fixed.

This library is used to implemenet RSA digital signature verification
used in IMA/EVM integrity protection subsystem.

Due to patch size limitation, the patch is divided into 4 parts.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
2011-11-09 11:45:22 +02:00