frost/secp256k1-zkp
3
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Split ecdsa_sign logic into a new function and use it from ecdsa_sign and recovery

Browse Source
This commit is contained in:
Elichai Turkel
2020-05-27 00:37:59 +03:00
parent 5e1c885efb
commit 2876af4f8d
3 changed files with 44 additions and 47 deletions
Download Patch File Download Diff File Expand all files Collapse all files

14
src/util.h
View File

@@ -194,4 +194,18 @@ static SECP256K1_INLINE void memczero(void *s, size_t len, int flag) {
}
}
/** If flag is true, set *r equal to *a; otherwise leave it. Constant-time. Both *r and *a must be initialized and non-negative.*/
static SECP256K1_INLINE void secp256k1_int_cmov(int *r, const int *a, int flag) {
unsigned int mask0, mask1, r_masked, a_masked;
/* Casting a negative int to unsigned and back to int is implementation defined behavior */
VERIFY_CHECK(*r >= 0 && *a >= 0);
mask0 = (unsigned int)flag + ~0u;
mask1 = ~mask0;
r_masked = ((unsigned int)*r & mask0);
a_masked = ((unsigned int)*a & mask1);
*r = (int)(r_masked | a_masked);
}
#endif /* SECP256K1_UTIL_H */