0d82732 Improve VERIFY_CHECK of overflow in secp256k1_scalar_cadd_bit. This added check ensures that any curve order overflow doesn't go undetected due a uint32_t overflow. (Russell O'Connor)
8fe63e5 Increase robustness against UB. Thanks to elichai2 who noted that the literal '1' is a signed integer, and that shifting a signed 32-bit integer by 31 bits causes an overflow and yields undefined behaviour. While 'scalar_low_impl''s 'secp256k1_scalar_cadd_bit' is only used for testing purposes and currently the 'bit' parameter is only 0 or 1, it is better to avoid undefined behaviour in case the used domain of 'secp256k1_scalar_cadd_bit' expands. (roconnor-blockstream)
Pull request description:
Avoid possible, but unlikely undefined behaviour in `scalar_low_impl`'s `secp256k1_scalar_cadd_bit`.
Thanks to elichai2 who noted that the literal `1` is a signed integer, and that shifting a signed 32-bit integer by 31 bits causes an overflow and yields undefined behaviour.
Using the unsigned literal `1u` addresses the issue.
ACKs for commit 0d8273:
real-or-random:
ACK 0d82732a9a16cecc445e61c718ce9bdc2d228e76
jonasnick:
ACK 0d82732a9a16cecc445e61c718ce9bdc2d228e76
Tree-SHA512: 905be3b8b00aa5cc9bd6dabb543745119da8f34181d37765071f28abbc1d6ff3659e3f195b72c2f2d003006678823919668bc0d169ac8b8d4bcc5da671813c99
make ECMULT_GEN_PREC_BITS configurable
ecmult_static_context.h: add compile time config assertion (#3) - Prevents accidentally using a file which was generated with a
different configuration.
README: mention valgrind issue
With --with-ecmult-gen-precision=8, valgrind needs a max stack size
adjustment to not run into a stack switching heuristic:
http://valgrind.org/docs/manual/manual-core.html
> -max-stackframe= [default: 2000000]
> The maximum size of a stack frame. If the stack pointer moves by more than this amount then Valgrind will assume that the program is switching to a different stack.
You may need to use this option if your program has large stack-allocated arrays.
basic-config: undef ECMULT_WINDOW_SIZE before (re-)defining it
a11c76c59a431e3492994f71a968a838e398fb58 secp256k1/src/tests.c: Properly handle sscanf return value (Mustapha Abiola)
Pull request description:
This pull request fixes a bug which allows the `sh` variable to be used uninitialised
when sscanf(3) returns EOF.
Signed-off-by: Mustapha Abiola <mustapha@trilemma.net>
ACKs for top commit:
sipa:
ACK a11c76c59a431e3492994f71a968a838e398fb58.
practicalswift:
utACK a11c76c59a431e3492994f71a968a838e398fb58
real-or-random:
ACK a11c76c59a431e3492994f71a968a838e398fb58 I looked at the code
Tree-SHA512: fd9660a18e39ecf9366db94ccbcec2682b020223f4f982a4356ddf56c2fbdafa5edcd830db37be12b661c1ec0b15c57b9f34ba59ef4460187c9c2478376fbc88
74e2dbd JNI: fix use sig array (liuyujun)
Pull request description:
ACKs for commit 74e2db:
sipa:
ACK 74e2dbd68e07f752ac326a578e3071f9efa55e55. This is clearly an improvement.
real-or-random:
ACK 74e2dbd68e07f752ac326a578e3071f9efa55e55 I've read the code but haven't tested it
Tree-SHA512: 850b32e893463be4be28185dcc127d429afe4b6076036a078b7c61d590e0f4ea89127e448760b71c087cf70ffbefc52d87db77a5131bee81f3e4f95cfbd3bd3e
94ae7cb Moved a dereference so the null check will be before the dereferencing (Elichai Turkel)
Pull request description:
Before that even on debug the compiler could've assumed `a` isn't null and optimized `VERIFY_CHECK(a != NULL);` out.
This put the dereference after the check
Resolves#643
ACKs for commit 94ae7c:
sipa:
ACK 94ae7cbf83a34456e5cad721f61ea77fcc023a3f
Tree-SHA512: 8b986f202ede5bde1f14a8ecf25e339d64ee6cd5cb391c5f18b4ff58f946c3845902d1230bc80d110a0a33b37025d281bd4532afbdf03b1c9ca321097374eb8e
2cb73b1 scalar_impl.h: fix includes (Marko Bencun)
Pull request description:
group.h functions are not referenced.
utils.h added as functions like VERIFY_CHECK are used.
ACKs for commit 2cb73b:
sipa:
ACK 2cb73b1064c796f5902189e0850066299e87aa93
Tree-SHA512: b9c7367061c2a22d2c9266c61261edd47798551b03b878ecd2e005d858701487145589793406cb4e88e85cd3c769007132efac9c228d5ee288e487e7d308e1c2
This pull request fixes a bug which allows the `sh` variable to be used uninitialized when sscanf returns EOF.
Signed-off-by: Mustapha Abiola <mustapha@trilemma.net>
Thanks to elichai2 who noted that the literal '1' is a signed integer, and that shifting a signed 32-bit integer by 31 bits causes an overflow and yields undefined behaviour.
While 'scalar_low_impl''s 'secp256k1_scalar_cadd_bit' is only used for testing purposes and currently the 'bit' parameter is only 0 or 1, it is better to avoid undefined behaviour in case the used domain of 'secp256k1_scalar_cadd_bit' expands.
cd473e0 Avoid calling secp256k1_*_is_zero when secp256k1_*_set_b32 fails. (Gregory Maxwell)
Pull request description:
Most of the codebase correctly used short-cutting to avoid calling
_is_zero on possibly incompletely initialized elements, but a few
places were missed.
ACKs for commit cd473e:
sipa:
utACK cd473e02c372217c3a6608ce5afaa543ed78f891
jonasnick:
utACK cd473e02c372217c3a6608ce5afaa543ed78f891
Tree-SHA512: d6af2863f6795d2df26f2bd05a4e33085e88c45f7794601ea57e67238a2073ef1ee3ba0feab62a7fcbc0636c48dfd80eea07d0ca4f194414127f914b0478c732
dcf3920 Fix ability to compile tests without -DVERIFY. (Gregory Maxwell)
Pull request description:
Broken by 3f3964e4.
It's important that the tests are also run without -DVERIFY due to
the possibility that side-effects of a VERIFY_CHECK fix a bug that
would otherwise be detected.
Use of the verify_check macro in tests isn't sufficient.
ACKs for commit dcf392:
Tree-SHA512: ff7ca0e89e33f845656a4d7d18c0195d1378b020d67f89e900b18cf3d702aa81dd91ffd05a98953a481b83e4247eaf0c484bea12eab020efb3c966a456e8129f
14c7dbd Simplify control flow in DER parsing (Tim Ruffing)
ec8f20b Avoid out-of-bound pointers and integer overflows in size comparisons (Tim Ruffing)
01ee1b3 Parse DER-enconded length into a size_t instead of an int (Tim Ruffing)
3cb057f Fix possible integer overflow in DER parsing (Tim Ruffing)
Pull request description:
This is a result of auditing the code for overflow issues at random places. None of this is critical but I think all of it should be fixed.
I know this touches "red" code. I double-checked and triple-checked this but I can understand if some of the changes are not desirable because they change well-tested code.
Best reviewed in individual commits.
ACKs for commit 14c7db:
Tree-SHA512: 312dd3f961739752e1a861e75bd755920f634f87ee9668793e102c224434e8d21367452e114de729322c71a89f4fa82126aa5d32742f2bbbc091777c99515e10
Most of the codebase correctly used short-cutting to avoid calling
_is_zero on possibly incompletely initialized elements, but a few
places were missed.
9ab96f7 Use trivial algorithm in ecmult_multi if scratch space is small (Jonas Nick)
Pull request description:
`ecmult_multi` already selects the trivial algorithm if the scratch space is NULL. With this PR the trivial algorithm is also selected if the scratch space is too small to use pippenger or strauss instead of returning 0. That makes it more easier to avoid consensus relevant inconsistencies just because scratch space construction was messed up.
ACKs for commit 9ab96f:
real-or-random:
utACK 9ab96f7
Tree-SHA512: aa451adf8880af15cf167a59cb07fc411edc43f26c8eb0873bdae2774382ba182e2a1c54487912f8f2999cb0402d554b9d293e2fb9483234471348a1f43c6653
Broken by 3f3964e4.
It's important that the tests are also run without -DVERIFY due to
the possibility that side-effects of a VERIFY_CHECK fix a bug that
would otherwise be detected.
Use of the verify_check macro in tests isn't sufficient.