Define valid ECDSA keys in the documentation of seckey_verify

furszy · Mar 30, 2020 · f03df0e · f03df0e
1 parent 5894e1f
commit f03df0e
Showing 1 changed file with 5 additions and 0 deletions.
diff --git a/include/secp256k1.h b/include/secp256k1.h
@@ -552,6 +552,11 @@ SECP256K1_API int secp256k1_ecdsa_sign(
 ) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
 
 /** Verify an ECDSA secret key.
+ *
+ *  A secret key is valid if it is not 0 and less than the secp256k1 curve order
+ *  when interpreted as an integer (most significant byte first). The
+ *  probability of choosing a 32-byte string uniformly at random which is an
+ *  invalid secret key is negligible.
  *
  *  Returns: 1: secret key is valid
  *           0: secret key is invalid