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linux/lib/mpi/mpicoder.c

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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>
2011-08-31 14:05:16 +03:00
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>
2012-09-24 17:11:27 +01:00
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>
2015-08-28 09:27:15 +02:00
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>
2016-03-22 13:12:39 +01:00
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>
2016-03-22 13:12:41 +01:00
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>
2011-08-31 14:05:16 +03:00
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>
2012-09-24 17:11:27 +01:00
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 14:04:40 -07:00
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>
2012-09-24 17:11:27 +01:00
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>
2013-01-30 11:30:06 +02:00
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>
2012-09-24 17:11:27 +01:00
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>
2011-08-31 14:05:16 +03:00
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>
2012-01-26 19:13:16 +02:00
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>
2011-08-31 14:05:16 +03:00
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>
2013-01-30 11:30:06 +02:00
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>
2011-08-31 14:05:16 +03:00
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>
2012-01-26 19:13:16 +02:00
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>
2011-08-31 14:05:16 +03:00
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: 0f74fbf77d45 ("MPI: Fix mpi_read_buffer") Signed-off-by: Michal Marek <mmarek@suse.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-02-17 14:46:59 +01:00
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>
2015-06-15 13:18:36 -07:00
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>
2015-11-13 12:01:32 +01:00
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>
2015-06-15 13:18:36 -07:00
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>
2011-08-31 14:05:16 +03:00
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>
2015-06-15 13:18:36 -07:00
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>
2011-08-31 14:05:16 +03:00
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>
2015-06-15 13:18:36 -07:00
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>
2016-03-22 13:12:41 +01:00
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>
2015-06-15 13:18:36 -07:00
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: 0f74fbf77d45 ("MPI: Fix mpi_read_buffer") Signed-off-by: Michal Marek <mmarek@suse.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-02-17 14:46:59 +01:00
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>
2015-06-15 13:18:36 -07:00
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>
2015-11-13 12:01:32 +01:00
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>
2015-06-15 13:18:36 -07:00
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>
2011-08-31 14:05:16 +03:00
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>
2015-06-15 13:18:36 -07:00
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: 0f74fbf77d45 ("MPI: Fix mpi_read_buffer") Signed-off-by: Michal Marek <mmarek@suse.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-02-17 14:46:59 +01:00
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>
2015-06-15 13:18:36 -07:00
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>
2015-11-13 12:01:32 +01:00
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>
2015-06-15 13:18:36 -07:00
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>
2015-08-24 07:52:14 -07:00
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>
2011-08-31 14:05:16 +03:00
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>
2016-03-22 13:12:40 +01:00
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>
2011-08-31 14:05:16 +03:00
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>
2016-03-22 13:12:41 +01:00
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>
2011-08-31 14:05:16 +03:00
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>
2016-03-22 13:12:41 +01:00
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>
2011-08-31 14:05:16 +03:00
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 9cbe21d8f89d ("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: 9cbe21d8f89d ("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>
2016-03-22 13:12:42 +01:00
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>
2011-08-31 14:05:16 +03:00
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>
2015-06-15 13:18:36 -07:00
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>
2015-08-24 07:52:14 -07:00
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>
2015-06-15 13:18:36 -07:00
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>
2011-08-31 14:05:16 +03:00
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>
2013-01-30 11:30:06 +02:00
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>
2011-08-31 14:05:16 +03:00
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>
2015-10-08 09:26:50 -07:00
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>
2015-11-13 12:01:32 +01:00
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>
2015-10-08 09:26:50 -07:00
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>
2016-03-22 13:12:39 +01:00
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>
2015-10-08 09:26:50 -07:00
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: 0f74fbf77d45 ("MPI: Fix mpi_read_buffer") Signed-off-by: Michal Marek <mmarek@suse.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-02-17 14:46:59 +01:00
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>
2015-10-08 09:26:50 -07:00
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>
2015-11-13 12:01:32 +01:00
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>
2015-10-08 09:26:50 -07:00
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: 0f74fbf77d45 ("MPI: Fix mpi_read_buffer") Signed-off-by: Michal Marek <mmarek@suse.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-02-17 14:46:59 +01:00
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>
2015-10-08 09:26:50 -07:00
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>
2015-11-13 12:01:32 +01:00
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>
2015-10-08 09:26:50 -07:00
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: 2d4d1eea540b ("lib/mpi: Add mpi sgl helpers") Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-03-22 13:12:35 +01:00
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>
2015-10-08 09:26:50 -07:00
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>
2016-03-22 13:12:39 +01:00
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>
2015-10-08 09:26:50 -07:00
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>
2016-03-22 13:12:39 +01:00
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>
2015-10-08 09:26:50 -07:00
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>
2016-03-22 13:12:36 +01:00
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: 2d4d1eea540b ("lib/mpi: Add mpi sgl helpers") Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-03-22 13:12:35 +01:00
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>
2016-03-22 13:12:36 +01:00
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>
2015-10-08 09:26:50 -07:00
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>
2016-03-22 13:12:39 +01:00
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>
2015-10-08 09:26:50 -07:00
lib/mpi: mpi_read_raw_from_sgl(): replace len argument by nbytes Currently, the nbytes local variable is calculated from the len argument as follows: ... mpi_read_raw_from_sgl(..., unsigned int len) { unsigned nbytes; ... if (!ents) nbytes = 0; else nbytes = len - lzeros; ... } Given that nbytes is derived from len in a trivial way and that the len argument is shadowed by a local len variable in several loops, this is just confusing. Rename the len argument to nbytes and get rid of the nbytes local variable. Do the nbytes calculation in place. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-03-22 13:12:43 +01:00
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>
2015-10-08 09:26:50 -07:00
lib/mpi: mpi_read_raw_from_sgl(): replace len argument by nbytes Currently, the nbytes local variable is calculated from the len argument as follows: ... mpi_read_raw_from_sgl(..., unsigned int len) { unsigned nbytes; ... if (!ents) nbytes = 0; else nbytes = len - lzeros; ... } Given that nbytes is derived from len in a trivial way and that the len argument is shadowed by a local len variable in several loops, this is just confusing. Rename the len argument to nbytes and get rid of the nbytes local variable. Do the nbytes calculation in place. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-03-22 13:12:43 +01:00
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>
2015-10-08 09:26:50 -07:00
lib/mpi: mpi_read_raw_from_sgl(): replace len argument by nbytes Currently, the nbytes local variable is calculated from the len argument as follows: ... mpi_read_raw_from_sgl(..., unsigned int len) { unsigned nbytes; ... if (!ents) nbytes = 0; else nbytes = len - lzeros; ... } Given that nbytes is derived from len in a trivial way and that the len argument is shadowed by a local len variable in several loops, this is just confusing. Rename the len argument to nbytes and get rid of the nbytes local variable. Do the nbytes calculation in place. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-03-22 13:12:43 +01:00
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>
2015-10-08 09:26:50 -07:00
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>
2015-10-18 12:45:18 +02:00
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>
2015-10-08 09:26:50 -07:00
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>
2015-10-18 12:45:18 +02:00
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>
2015-10-08 09:26:50 -07:00
lib/mpi: mpi_read_raw_from_sgl(): don't include leading zero SGEs in nbytes At the very beginning of mpi_read_raw_from_sgl(), the leading zeros of the input scatterlist are counted: lzeros = 0; for_each_sg(sgl, sg, ents, i) { ... if (/* sg contains nonzero bytes */) break; /* sg contains nothing but zeros here */ ents--; lzeros = 0; } Later on, the total number of trailing nonzero bytes is calculated by subtracting the number of leading zero bytes from the total number of input bytes: nbytes -= lzeros; However, since lzeros gets reset to zero for each completely zero leading sg in the loop above, it doesn't include those. Besides wasting resources by allocating a too large output buffer, this mistake propagates into the calculation of x, the number of leading zeros within the most significant output limb: x = BYTES_PER_MPI_LIMB - nbytes % BYTES_PER_MPI_LIMB; What's more, the low order bytes of the output, equal in number to the extra bytes in nbytes, are left uninitialized. Fix this by adjusting nbytes for each completely zero leading scatterlist entry. Fixes: 2d4d1eea540b ("lib/mpi: Add mpi sgl helpers") Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-03-22 13:12:44 +01:00
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>
2015-10-08 09:26:50 -07:00
lib/mpi: mpi_read_raw_from_sgl(): don't include leading zero SGEs in nbytes At the very beginning of mpi_read_raw_from_sgl(), the leading zeros of the input scatterlist are counted: lzeros = 0; for_each_sg(sgl, sg, ents, i) { ... if (/* sg contains nonzero bytes */) break; /* sg contains nothing but zeros here */ ents--; lzeros = 0; } Later on, the total number of trailing nonzero bytes is calculated by subtracting the number of leading zero bytes from the total number of input bytes: nbytes -= lzeros; However, since lzeros gets reset to zero for each completely zero leading sg in the loop above, it doesn't include those. Besides wasting resources by allocating a too large output buffer, this mistake propagates into the calculation of x, the number of leading zeros within the most significant output limb: x = BYTES_PER_MPI_LIMB - nbytes % BYTES_PER_MPI_LIMB; What's more, the low order bytes of the output, equal in number to the extra bytes in nbytes, are left uninitialized. Fix this by adjusting nbytes for each completely zero leading scatterlist entry. Fixes: 2d4d1eea540b ("lib/mpi: Add mpi sgl helpers") Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-03-22 13:12:44 +01:00
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>
2015-10-08 09:26:50 -07:00
lib/mpi: mpi_read_raw_from_sgl(): fix nbits calculation The number of bits, nbits, is calculated in mpi_read_raw_from_sgl() as follows: nbits = nbytes * 8; Afterwards, the number of leading zero bits of the first byte get subtracted: nbits -= count_leading_zeros(*(u8 *)(sg_virt(sgl) + lzeros)); However, count_leading_zeros() takes an unsigned long and thus, the u8 gets promoted to an unsigned long. Thus, the above doesn't subtract the number of leading zeros in the most significant nonzero input byte from nbits, but the number of leading zeros of the most significant nonzero input byte promoted to unsigned long, i.e. BITS_PER_LONG - 8 too many. Fix this by subtracting count_leading_zeros(...) - (BITS_PER_LONG - 8) from nbits only. Fixes: 2d4d1eea540b ("lib/mpi: Add mpi sgl helpers") Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-03-22 13:17:27 +01:00
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>
2015-10-08 09:26:50 -07:00
lib/mpi: mpi_read_raw_from_sgl(): sanitize meaning of indices Within the byte reading loop in mpi_read_raw_sgl(), there are two housekeeping indices used, z and x. At all times, the index z represents the number of output bytes covered by the input SGEs for which processing has completed so far. This includes any leading zero bytes within the most significant limb. The index x changes its meaning after the first outer loop's iteration though: while processing the first input SGE, it represents "number of leading zero bytes in most significant output limb" + "current position within current SGE" For the remaining SGEs OTOH, x corresponds just to "current position within current SGE" After all, it is only the sum of z and x that has any meaning for the output buffer and thus, the "number of leading zero bytes in most significant output limb" part can be moved away from x into z from the beginning, opening up the opportunity for cleaner code. Before the outer loop iterating over the SGEs, don't initialize z with zero, but with the number of leading zero bytes in the most significant output limb. For the inner loop iterating over a single SGE's bytes, get rid of the buf_shift offset to x' bounds and let x run from zero to sg->length - 1. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-03-22 13:18:07 +01:00
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>
2015-10-08 09:26:50 -07:00
lib/mpi: mpi_read_raw_from_sgl(): sanitize meaning of indices Within the byte reading loop in mpi_read_raw_sgl(), there are two housekeeping indices used, z and x. At all times, the index z represents the number of output bytes covered by the input SGEs for which processing has completed so far. This includes any leading zero bytes within the most significant limb. The index x changes its meaning after the first outer loop's iteration though: while processing the first input SGE, it represents "number of leading zero bytes in most significant output limb" + "current position within current SGE" For the remaining SGEs OTOH, x corresponds just to "current position within current SGE" After all, it is only the sum of z and x that has any meaning for the output buffer and thus, the "number of leading zero bytes in most significant output limb" part can be moved away from x into z from the beginning, opening up the opportunity for cleaner code. Before the outer loop iterating over the SGEs, don't initialize z with zero, but with the number of leading zero bytes in the most significant output limb. For the inner loop iterating over a single SGE's bytes, get rid of the buf_shift offset to x' bounds and let x run from zero to sg->length - 1. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-03-22 13:18:07 +01:00
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>
2015-10-08 09:26:50 -07:00