Previously the length of the SM2 plaintext could be incorrectly calculated.
The plaintext length was calculated by taking the ciphertext length and
taking off an "overhead" value.
The overhead value was assumed to have a "fixed" element of 10 bytes.
This is incorrect since in some circumstances it can be more than 10 bytes.
Additionally the overhead included the length of two integers C1x and C1y,
which were assumed to be the same length as the field size (32 bytes for
the SM2 curve). However in some cases these integers can have an additional
padding byte when the msb is set, to disambiguate them from negative
integers. Additionally the integers can also be less than 32 bytes in
length in some cases.
If the calculated overhead is incorrect and larger than the actual value
this can result in the calculated plaintext length being too small.
Applications are likely to allocate buffer sizes based on this and therefore
a buffer overrun can occur.
CVE-2021-3711
Issue reported by John Ouyang.
Reviewed-by: Paul Dale <pauli@openssl.org>
Reviewed-by: Nicola Tuveri <nic.tuv@gmail.com>
Partial fix for #12964
This adds ossl_ names for the following symbols:
ec_*, ecx_*, ecdh_*, ecdsa_*, sm2_*
Reviewed-by: Paul Dale <pauli@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/14231)
Since these are KATs, the trailing randomness consumed by the ec module
does not really matter. So make the fake random buffer circular.
Reviewed-by: Nicola Tuveri <nic.tuv@gmail.com>
Reviewed-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
(Merged from https://github.com/openssl/openssl/pull/11435)
Use of the low level ECDSA and EC_KEY_METHOD functions has been informally discouraged for a
long time. We now formally deprecate them.
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/10960)
Currently, there are two different directories which contain internal
header files of libcrypto which are meant to be shared internally:
While header files in 'include/internal' are intended to be shared
between libcrypto and libssl, the files in 'crypto/include/internal'
are intended to be shared inside libcrypto only.
To make things complicated, the include search path is set up in such
a way that the directive #include "internal/file.h" could refer to
a file in either of these two directoroes. This makes it necessary
in some cases to add a '_int.h' suffix to some files to resolve this
ambiguity:
#include "internal/file.h" # located in 'include/internal'
#include "internal/file_int.h" # located in 'crypto/include/internal'
This commit moves the private crypto headers from
'crypto/include/internal' to 'include/crypto'
As a result, the include directives become unambiguous
#include "internal/file.h" # located in 'include/internal'
#include "crypto/file.h" # located in 'include/crypto'
hence the superfluous '_int.h' suffixes can be stripped.
The files 'store_int.h' and 'store.h' need to be treated specially;
they are joined into a single file.
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/9333)
