72ae443 Improve perf. of cmov-based table lookup (Peter Dettman)
92e53fc Implement endomorphism optimization for secp256k1_ecmult_const (Andrew Poelstra)
ed35d43 Make `secp256k1_scalar_add_bit` conditional; make `secp256k1_scalar_split_lambda_var` constant time (Andrew Poelstra)
91c0ce9 Add benchmarks for ECDH and const-time multiplication (Andrew Poelstra)
0739bbb Add ECDH module which works by hashing the output of ecmult_const (Andrew Poelstra)
4401500 Add constant-time multiply `secp256k1_ecmult_const` for ECDH (Andrew Poelstra)
baa75da tests: add a couple tests (Andrew Poelstra)
This has the effect of making `secp256k1_scalar_mul_shift_var` constant
time in both input scalars. Keep the _var name because it is NOT constant
time in the shift amount.
As used in `secp256k1_scalar_split_lambda_var`, the shift is always
the constant 272, so this function becomes constant time, and it
loses the `_var` suffix.
Designed with clear separation of the wNAF conversion, precomputation
and exponentiation (since the precomp at least we will probably want
to separate in the API for users who reuse points a lot.
Future work:
- actually separate precomp in the API
- do multiexp rather than single exponentiation
BUILT_SOURCES simply forces the header to be built first.
Use real dependencies instead. This fixes builds with dependency tracking
disabled where a real target is specified.
As a bonus, this also fixes the issue of gen_context and the header not being
rebuilt when gen_context.c is touched.
- Add zero/one sanity check tests for ecmult
- Add unit test for secp256k1_scalar_split_lambda_var
- Typo fix in `ge_equals_ge`; was comparing b->y to itself, should
have been comparing a->y to b->y
- Normalize y-coordinate in `random_group_element_test`; this is
needed to pass random group elements as the first argument to
`ge_equals_ge`, which I will do in a future commit.
18c329c Remove the internal secp256k1_ecdsa_sig_t type (Pieter Wuille)
74a2acd Add a secp256k1_ecdsa_signature_t type (Pieter Wuille)
23cfa91 Introduce secp256k1_pubkey_t type (Pieter Wuille)
This update is to make libsecp256k1 build on OpenBSD (more specifically OpenBSD 5.7 with Autotools 2.69).
Without the "AM_PROG_CC_C_O" line in configure.ac, ./autogen.sh crashes with "Makefile.am: C objects in subdir but `AM_PROG_CC_C_O' not in `configure.ac'\nautoreconf-2.69: automake failed with exit status: 1".
Gen_context was unable to find the required headers without some
autotools fixups. Make dist was also broken without the extra
sources for the host side table builder utility.
This vastly shrinks the size of the context required for signing on devices with
memory-mapped Flash.
Tables are generated by the new gen_context tool into a header.
5a43124 Save 1 _fe_negate since s1 == -s2 (Peter Dettman)
a5d796e Update code comments (Peter Dettman)
7d054cd Refactor to save a _fe_negate (Peter Dettman)
b28d02a Refactor to remove a local var (Peter Dettman)
55e7fc3 Perf. improvement in _gej_add_ge (Peter Dettman)
