openbsd/src/lib/libcrypto/bn/bn_gcd.c, branch OPENBSD_7_9_BASEA mirror of https://github.com/libressl/openbsd.git
https://git.lua4.win/openbsd/atom?h=OPENBSD_7_9_BASE2025-06-02T12:40:10+00:00bn_gcd: fix wacky indentation found by smatch2025-06-02T12:40:10+00:00tb2025-06-02T12:40:10+00:00urn:sha1:a0e8b5e2ce5f6c14ed133fc2350b4268645c65d5
via/ok jsg
Use err_local.h rather than err.h in most places2025-05-10T05:54:39+00:00tb2025-05-10T05:54:39+00:00urn:sha1:41e8f99dd1625a9f0c80ce9d4383e95b18e85709
ok jsing
Hide symbols in bn.h2024-04-10T14:58:06+00:00beck2024-04-10T14:58:06+00:00urn:sha1:c1002fc07c1599164ea7518630da25bd606c9993
Mark them LCRYPTO_UNUSED appropriately and remove the LIBRESSL_INTERNAL
guards around them
ok tb@
Fix variable reuse in BN_mod_inverse()2023-06-02T17:15:30+00:00tb2023-06-02T17:15:30+00:00urn:sha1:bb185fc15eb97e85801b9f2ecdd0bfb242f9231a
The somewhat strange calculation m = a^{-1} (mod m) can return 0. This
breaks because of BN_nnmod() having delicate semantics of which variable
can be reused. BN_nnmod(a, a, m, ctx) works and the library relies on that.
Here, the code ends up doing BN_nnmod(m, a, m, ctx) and this doesn't work.
If the result of the initial BN_mod() is negative, then BN_nnmod() will
return 0.
Problem reported by Guido Vranken in
https://github.com/openssl/openssl/issues/21110
This code is well covered by regress, but it does not currently have
explicit test coverage. Such will be added soon.
ok beck jsing
Remove some doubled empty lines2023-04-09T18:38:59+00:00tb2023-04-09T18:38:59+00:00urn:sha1:1ddb2ff985be4a287c82d504f59d7ae8323def92Compress euclid() a little2023-04-03T21:43:43+00:00tb2023-04-03T21:43:43+00:00urn:sha1:b5c34e79a0f8a9c8f04fad14bc858c12039ecc60
This function is spread out over way too many lines and has too much
repetition. Once this is made a little more compact, it becomes clearer
that this is a somewhat obfuscated version of binary gcd (it is not
constant time therefore cryptographically unsound. It is not used
internally). This will likely go away later.
ok jsing
Indent labels2023-04-01T11:10:55+00:00tb2023-04-01T11:10:55+00:00urn:sha1:41392dc26c09906ca7a9319a0980cdc04f6aae38Group the non-constant time gcd functions together2023-04-01T11:08:43+00:00tb2023-04-01T11:08:43+00:00urn:sha1:9bf5abd4bce2c2aac1ab6872653f28d9d09eb26b
The only consumer of euclid() is BN_gcd(), which, in turn is only
used by BN_gcd_nonct(). Group them together rather than having
parts of the constant time implementation separate them.
This moves two functions to a different place in the file.
Replace the remaining BN_copy() with bn_copy()2023-03-27T10:25:02+00:00tb2023-03-27T10:25:02+00:00urn:sha1:aeb32cad44c92f3786167b06a0f9c4310cbb713d
ok jsing
Convert BN_copy() with explicit comparison against NULL to bn_copy()2023-03-27T10:21:23+00:00tb2023-03-27T10:21:23+00:00urn:sha1:a81a8ccd42d8aec45ab93fd62a292dc1d27c0db6
ok jsing