f431b3f28ac95a3645ad5a6dc96b878fa30a1de3 valgrind_ctime_test: Add schnorrsig_sign (Jonas Nick)
16ffa9d97cef93f49544b016339c107882f9a1c3 schnorrsig: Add taproot test case (Jonas Nick)
8dfd53ee3fa059562483d1867815f78b9e00d947 schnorrsig: Add benchmark for sign and verify (Jonas Nick)
4e43520026f5bcd182d21f0759bac159ef47bb62 schnorrsig: Add BIP-340 compatible signing and verification (Jonas Nick)
7332d2db6b62fda851f9ed8adbfda187a875b84e schnorrsig: Add BIP-340 nonce function (Jonas Nick)
7a703fd97db0161bae07ef84513ddde6e0d27353 schnorrsig: Init empty experimental module (Jonas Nick)
eabd9bc46a31c0da6db6d88840eadbe9006447b1 Allow initializing tagged sha256 (Jonas Nick)
6fcb5b845d2832ce019d60507033f74426290768 extrakeys: Add keypair_xonly_tweak_add (Jonas Nick)
58254463f9a2e96d893157a341c9953c440fdf60 extrakeys: Add keypair struct with create, pub and pub_xonly (Jonas Nick)
f0010349b876bc6b3f0a6ec6c8bad0b12ca17b51 Separate helper functions for pubkey_create and seckey_tweak_add (Jonas Nick)
910d9c284c33b77774a9316d4524f313357d441c extrakeys: Add xonly_pubkey_tweak_add & xonly_pubkey_tweak_add_test (Jonas Nick)
176bfb1110147b5dca1834ea071acc846fb1cab3 Separate helper function for ec_pubkey_tweak_add (Jonas Nick)
4cd2ee474d178bd1b5602486104db346a7562c67 extrakeys: Add xonly_pubkey with serialize, parse and from_pubkey (Jonas Nick)
47e6618e11813cfabe91f0909ca031f960cb7dd4 extrakeys: Init empty experimental module (Jonas Nick)
3e08b02e2a78f2a1fc457efab665db8ab8085373 Make the secp256k1_declassify argument constant (Jonas Nick)
Pull request description:
This PR implements signing, verification and batch verification as described in [BIP-340](https://github.com/bitcoin/bips/blob/master/bip-0340.mediawiki) in an experimental module named `schnorrsig`. It includes the test vectors and a benchmarking tool.
This PR also adds a module `extrakeys` that allows [BIP-341](https://github.com/bitcoin/bips/blob/master/bip-0341.mediawiki)-style key tweaking.
(Adding ChaCha20 as a CSPRNG and batch verification was moved to PR #760).
In order to enable the module run `./configure` with `--enable-experimental --enable-module-schnorrsig`.
Based on apoelstra's work.
ACKs for top commit:
gmaxwell:
ACK f431b3f28ac95a3645ad5a6dc96b878fa30a1de3 (exactly matches the previous post-fixup version which I have already reviewed and tested)
sipa:
ACK f431b3f28ac95a3645ad5a6dc96b878fa30a1de3
real-or-random:
ACK f431b3f28ac95a3645ad5a6dc96b878fa30a1de3 careful code review
Tree-SHA512: e15e849c7bb65cdc5d7b1d6874678e275a71e4514de9d5432ec1700de3ba92aa9f381915813f4729057af152d90eea26aabb976ed297019c5767e59cf0bbc693
8bc6aeffa9a191e677cb9e3a22fff130f16990f3 Add SHA256 selftest (Pieter Wuille)
5e5fb28b4a45d7e35e55b5f5feead2be07bccc28 Use additional system macros to figure out endianness (Pieter Wuille)
Pull request description:
These are all the architecture macros I could find with known endianness. Use those as a fallback when __BYTE_ORDER__ isn't available.
See https://github.com/bitcoin-core/secp256k1/pull/787#issuecomment-673764652
It also adds a SHA256 selftest, so that improperly overriding the endianness detection will be detected at runtime.
ACKs for top commit:
real-or-random:
ACK 8bc6aeffa9a191e677cb9e3a22fff130f16990f3 I read the diff, and tested that the self-test passes/fails with/without the correct endianness setting
gmaxwell:
ACK 8bc6aeffa9a191e677cb9e3a22fff130f16990f3 looks good and I also ran the tests on MIPS-BE and verified that forcing it to LE makes the runtime test fail.
Tree-SHA512: aca4cebcd0715dcf5b58f5763cb4283af238987f43bd83a650e38e127f348131692b2eed7ae5b2ae96046d9b971fc77c6ab44467689399fe470a605c3458ecc5
ECDSA signing has a retry loop for the exceptionally unlikely case
that S==0. S is not a secret at this point and this case is so
rare that it will never be observed but branching on it will trip
up tools analysing if the code is constant time with respect to
secrets.
Derandomized ECDSA can also loop on k being zero or overflowing,
and while k is a secret these cases are too rare (1:2^255) to
ever observe and are also of no concern.
This adds a function for marking memory as no-longer-secret and
sets it up for use with the valgrind memcheck constant-time
test.
There were several places where the code was non-constant time
for invalid secret inputs. These are harmless under sane use
but get in the way of automatic const-time validation.
(Nonce overflow in signing is not addressed, nor is s==0 in
signing)
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
Most of the codebase correctly used short-cutting to avoid calling
_is_zero on possibly incompletely initialized elements, but a few
places were missed.
Before this commit secp256k1_context_randomize called illegal_callback
when called on a context not initialized for signing. This is not
documented. Moreover, it is not desirable because non-signing contexts
may use randomization in the future.
This commit makes secp256k1_context_randomize a noop in this case. This
is safe because the context cannot be used for signing anyway.
This fixes#573 and it fixesrust-bitcoin/rust-secp256k1#82.
c7680e5 Reduce usage of hardcoded size constants (Thomas Snider)
Pull request description:
In particular the usage of keylen in nonce_function_rfc6979 seemed precarious - in one conditional it was unconditionally set, then in the next it was added to. While it was clearly correct as written, I think this change makes it easier to reason about for new eyes and more resistant to breakage if there is any future change to what gets fed into the PRNG.
Tree-SHA512: 2241c183acc0f318f85a11ccff7fe28de7777bc53dea93ab8308bad15871047a268c6a2b36f77a599dce536fca48ab305ea746223840bc10953c893daffa0a50
Make sure we clear the nonce data even if the nonce function fails (it may have written partial data), and call memset only once in the case we iterate to produce a valid signature.
The `ARG_CHECK` macro requires that a variable called `ctx` exist and be
non-NULL. However, in several functions that do not use the context variable,
we simply ignore it with `(void)ctx`. Replace these with explicit checks for
non-NULLness to avoid invalid memory accesses.
Squashed and rebased. Thanks to @theuni and @faizkhan00 for doing
the majority of work here! Also thanks to @btchip for help with debugging
and review.
Makes secp256k1_ec_pubkey_serialize set the length to zero on failure,
also makes secp256k1_ec_pubkey_create set the pubkey to zeros when
the key argument is NULL.
Also adds many additional ARGCHECK tests.
