Update source files for pre-3.0 deprecation

Reviewed-by: Tim Hudson <tjh@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/10364)

Reorganize local header files

Apart from public and internal header files, there is a third type called
local header files, which are located next to source files in the source
direc

Reorganize local header files

Apart from public and internal header files, there is a third type called
local header files, which are located next to source files in the source
directory. Currently, they have different suffixes like

'*_lcl.h', '*_local.h', or '*_int.h'

This commit changes the different suffixes to '*_local.h' uniformly.

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/9333)

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Uniform BN_bn2binpad() and BN_bn2lebinpad() implementations

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
(Merged from https://

Uniform BN_bn2binpad() and BN_bn2lebinpad() implementations

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
(Merged from https://github.com/openssl/openssl/pull/9511)

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Make BN_num_bits() consttime upon BN_FLG_CONSTTIME

This issue was partially addressed by commit
972c87dfc7e765bd28a4964519c362f0d3a58ca4, which hardened its callee
BN_num_bits_word()

Make BN_num_bits() consttime upon BN_FLG_CONSTTIME

This issue was partially addressed by commit
972c87dfc7e765bd28a4964519c362f0d3a58ca4, which hardened its callee
BN_num_bits_word() to avoid leaking the most-significant word of its
argument via branching and memory access pattern.
The commit message also reported:
> There are a few places where BN_num_bits is called on an input where
> the bit length is also secret. This does *not* fully resolve those
> cases as we still only look at the top word.

BN_num_bits() is called directly or indirectly (e.g., through
BN_num_bytes() or BN_bn2binpad() ) in various parts of the `crypto/ec`
code, notably in all the currently supported implementations of scalar
multiplication (in the generic path through ec_scalar_mul_ladder() as
well as in dedicated methods like ecp_nistp{224,256,521}.c and
ecp_nistz256.c).

Under the right conditions, a motivated SCA attacker could retrieve the
secret bitlength of a secret nonce through this vulnerability,
potentially leading, ultimately, to recover a long-term secret key.

With this commit, exclusively for BIGNUMs that are flagged with
BN_FLG_CONSTTIME, instead of accessing only bn->top, all the limbs of
the BIGNUM are accessed up to bn->dmax and bitwise masking is used to
avoid branching.

Memory access pattern still leaks bn->dmax, the size of the lazily
allocated buffer for representing the BIGNUM, which is inevitable with
the current BIGNUM architecture: reading past bn->dmax would be an
out-of-bound read.
As such, it's the caller responsibility to ensure that bn->dmax does not
leak secret information, by explicitly expanding the internal BIGNUM
buffer to a public value sufficient to avoid any lazy reallocation
while manipulating it: this should be already done at the top level
alongside setting the BN_FLG_CONSTTIME.

Thanks to David Schrammel and Samuel Weiser for reporting this issue
through responsible disclosure.

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
(Merged from https://github.com/openssl/openssl/pull/9511)

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Avoid double clearing some BIGNUMs

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/9438)

Added NULL check to BN_clear() & BN_CTX_end()

Reviewed-by: Paul Dale <paul.dale@oracle.com>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl

Added NULL check to BN_clear() & BN_CTX_end()

Reviewed-by: Paul Dale <paul.dale@oracle.com>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/8518)

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Add BN_native2bn and BN_bn2nativepad, for native BIGNUM import/export

These are a couple of utility functions, to make import and export of
BIGNUMs to byte strings in platform native for

Add BN_native2bn and BN_bn2nativepad, for native BIGNUM import/export

These are a couple of utility functions, to make import and export of
BIGNUMs to byte strings in platform native for (little-endian or
big-endian) easier.

Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/8346)

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Ensure bn_cmp_words can handle the case where n == 0

Thanks to David Benjamin who reported this, performed the analysis and
suggested the patch. I have incorporated some of his analysis

Ensure bn_cmp_words can handle the case where n == 0

Thanks to David Benjamin who reported this, performed the analysis and
suggested the patch. I have incorporated some of his analysis in the
comments below.

This issue can cause an out-of-bounds read. It is believed that this was
not reachable until the recent "fixed top" changes. Analysis has so far
only identified one code path that can encounter this - although it is
possible that others may be found. The one code path only impacts 1.0.2 in
certain builds. The fuzzer found a path in RSA where iqmp is too large. If
the input is all zeros, the RSA CRT logic will multiply a padded zero by
iqmp. Two mitigating factors:

- Private keys which trip this are invalid (iqmp is not reduced mod p).
Only systems which take untrusted private keys care.
- In OpenSSL 1.1.x, there is a check which rejects the oversize iqmp,
so the bug is only reproducible in 1.0.2 so far.

Fortunately, the bug appears to be relatively harmless. The consequences of
bn_cmp_word's misbehavior are:

- OpenSSL may crash if the buffers are page-aligned and the previous page is
non-existent.
- OpenSSL will incorrectly treat two BN_ULONG buffers as not equal when they
are equal.
- Side channel concerns.

The first is indeed a concern and is a DoS bug. The second is fine in this
context. bn_cmp_word and bn_cmp_part_words are used to compute abs(a0 - a1)
in Karatsuba. If a0 = a1, it does not matter whether we use a0 - a1 or
a1 - a0. The third would be worth thinking about, but it is overshadowed
by the entire Karatsuba implementation not being constant time.

Due to the difficulty of tripping this and the low impact no CVE is felt
necessary for this issue.

Reviewed-by: Paul Dale <paul.dale@oracle.com>
Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/8326)

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Following the license change, modify the boilerplates in crypto/bn/

[skip ci]

Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/7

Following the license change, modify the boilerplates in crypto/bn/

[skip ci]

Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/7777)

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Refactor the computation of API version limits

Previously, the API version limit was indicated with a numeric version
number. This was "natural" in the pre-3.0.0 because the version was

Refactor the computation of API version limits

Previously, the API version limit was indicated with a numeric version
number. This was "natural" in the pre-3.0.0 because the version was
this simple number.

With 3.0.0, the version is divided into three separate numbers, and
it's only the major number that counts, but we still need to be able
to support pre-3.0.0 version limits.

Therefore, we allow OPENSSL_API_COMPAT to be defined with a pre-3.0.0
style numeric version number or with a simple major number, i.e. can
be defined like this for any application:

-D OPENSSL_API_COMPAT=0x10100000L
-D OPENSSL_API_COMPAT=3

Since the pre-3.0.0 numerical version numbers are high, it's easy to
distinguish between a simple major number and a pre-3.0.0 numerical
version number and to thereby support both forms at the same time.

Internally, we define the following macros depending on the value of
OPENSSL_API_COMPAT:

OPENSSL_API_0_9_8
OPENSSL_API_1_0_0
OPENSSL_API_1_1_0
OPENSSL_API_3

They indicate that functions marked for deprecation in the
corresponding major release shall not be built if defined.

Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/7724)

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Clean up BN_consttime_swap.

Updated "condition" logic lifted from Theo Buehler's LibreSSL commit https://github.com/libressl-portable/openbsd/commit/517358603b4be76d48a50007a0d414c2072697dd

Clean up BN_consttime_swap.

Updated "condition" logic lifted from Theo Buehler's LibreSSL commit https://github.com/libressl-portable/openbsd/commit/517358603b4be76d48a50007a0d414c2072697dd

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Nicola Tuveri <nic.tuv@gmail.com>
(Merged from https://github.com/openssl/openssl/pull/7619)

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[crypto/bn] swap BN_FLG_FIXED_TOP too

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Nicola Tuveri <nic.tuv@gmail.com>

[crypto/bn] swap BN_FLG_FIXED_TOP too

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Nicola Tuveri <nic.tuv@gmail.com>
(Merged from https://github.com/openssl/openssl/pull/7599)

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bn/bn_lib.c: conceal even memmory access pattern in bn2binpad.

Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/6915)

bn/bn_lib.c address Coverity nit in bn2binpad.

It was false positive, but one can as well view it as readability issue.
Switch even to unsigned indices because % BN_BYTES takes 4-6 instr

bn/bn_lib.c address Coverity nit in bn2binpad.

It was false positive, but one can as well view it as readability issue.
Switch even to unsigned indices because % BN_BYTES takes 4-6 instructions
with signed dividend vs. 1 (one) with unsigned.

Reviewed-by: Rich Salz <rsalz@openssl.org>

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bn/bn_lib.c: make BN_bn2binpad computationally constant-time.

"Computationally constant-time" means that it might still leak
information about input's length, but only in cases when inpu

bn/bn_lib.c: make BN_bn2binpad computationally constant-time.

"Computationally constant-time" means that it might still leak
information about input's length, but only in cases when input
is missing complete BN_ULONG limbs. But even then leak is possible
only if attacker can observe memory access pattern with limb
granularity.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5254)

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bn/bn_lib.c: add BN_FLG_FIXED_TOP flag.

The new flag marks vectors that were not treated with bn_correct_top,
in other words such vectors are permitted to be zero padded. For now
it'

bn/bn_lib.c: add BN_FLG_FIXED_TOP flag.

The new flag marks vectors that were not treated with bn_correct_top,
in other words such vectors are permitted to be zero padded. For now
it's BN_DEBUG-only flag, as initial use case for zero-padded vectors
would be controlled Montgomery multiplication/exponentiation, not
general purpose. For general purpose use another type might be more
appropriate. Advantage of this suggestion is that it's possible to
back-port it...

bn/bn_div.c: fix memory sanitizer problem.
bn/bn_sqr.c: harmonize with BN_mul.

Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: David Benjamin <davidben@google.com>
(Merged from https://github.com/openssl/openssl/pull/6662)

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bn/bn_lib.c: remove bn_check_top from bn_expand2.

Trouble is that addition is postponing expansion till carry is
calculated, and if addition carries, top word can be zero, which
trig

bn/bn_lib.c: remove bn_check_top from bn_expand2.

Trouble is that addition is postponing expansion till carry is
calculated, and if addition carries, top word can be zero, which
triggers assertion in bn_check_top.

Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: David Benjamin <davidben@google.com>
(Merged from https://github.com/openssl/openssl/pull/6662)

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fix: BN_swap mishandles flags

Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6099)

Remove superfluous NULL checks. Add Andy's BN_FLG comment.

Reviewed-by: Andy Polyakov <appro@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com

Remove superfluous NULL checks. Add Andy's BN_FLG comment.

Reviewed-by: Andy Polyakov <appro@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6009)

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Elliptic curve scalar multiplication with timing attack defenses

Co-authored-by: Nicola Tuveri <nic.tuv@gmail.com>
Co-authored-by: Cesar Pereida Garcia <cesar.pereidagarcia@tut.fi>
C

Elliptic curve scalar multiplication with timing attack defenses

Co-authored-by: Nicola Tuveri <nic.tuv@gmail.com>
Co-authored-by: Cesar Pereida Garcia <cesar.pereidagarcia@tut.fi>
Co-authored-by: Sohaib ul Hassan <soh.19.hassan@gmail.com>

Reviewed-by: Andy Polyakov <appro@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6009)

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Make BN_num_bits_word constant-time.

(This patch was written by Andy Polyakov. I only wrote the commit
message. Mistakes in the analysis are my fault.)

BN_num_bits, by way of BN

Make BN_num_bits_word constant-time.

(This patch was written by Andy Polyakov. I only wrote the commit
message. Mistakes in the analysis are my fault.)

BN_num_bits, by way of BN_num_bits_word, currently leaks the
most-significant word of its argument via branching and memory access
pattern.

BN_num_bits is called on RSA prime factors in various places. These have
public bit lengths, but all bits beyond the high bit are secret. This
fully resolves those cases.

There are a few places where BN_num_bits is called on an input where the
bit length is also secret. This does *not* fully resolve those cases as
we still only look at the top word. Today, that is guaranteed to be
non-zero, but only because of the long-standing bn_correct_top timing
leak. Once that is fixed, a constant-time BN_num_bits on such inputs
must count bits on each word.

Instead, those cases should not call BN_num_bits at all. In particular,
BN_mod_exp_mont_consttime uses the exponent bit width to pick windows,
but it should be using the maximum bit width. The next patch will fix
this.

Thanks to Dinghao Wu, Danfeng Zhang, Shuai Wang, Pei Wang, and Xiao Liu
for reporting this issue.

Reviewed-by: Paul Dale <paul.dale@oracle.com>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5154)

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Copyright update of more files that have changed this year

Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/5110)

Revert BN_copy() flag copy semantics change

Commit 9f9442918a changed the semantics of BN_copy() to additionally
copy the BN_FLG_CONSTTIME flag if it is set. This turns out to be
ill

Revert BN_copy() flag copy semantics change

Commit 9f9442918a changed the semantics of BN_copy() to additionally
copy the BN_FLG_CONSTTIME flag if it is set. This turns out to be
ill advised as it has unintended consequences. For example calling
BN_mod_inverse_no_branch() can sometimes return a result with the flag
set and sometimes not as a result. This can lead to later failures if we
go down code branches that do not support constant time, but check for
the presence of the flag.

The original commit was made due to an issue in BN_MOD_CTX_set(). The
original PR fixed the problem in that function, but it was changed in
review to fix it in BN_copy() instead. The solution seems to be to revert
the BN_copy() change and go back to the originally proposed way.

Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/5080)

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Correct value for BN_security_bits()

The function BN_security_bits() uses the values from SP800-57 to assign
security bit values for different FF key sizes. However the value for 192

Correct value for BN_security_bits()

The function BN_security_bits() uses the values from SP800-57 to assign
security bit values for different FF key sizes. However the value for 192
security bits is wrong. SP800-57 has it as 7680 but the code had it as
7690.

Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4546)

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Remove parentheses of return.

Since return is inconsistent, I removed unnecessary parentheses and
unified them.

Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Matt

Remove parentheses of return.

Since return is inconsistent, I removed unnecessary parentheses and
unified them.

Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4541)

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