Update documentation regarding ECDSA curves support

README.md

@@ -8,7 +8,7 @@ These include:
 - Big Number (256 bit) Arithmetics
 - BIP32 Hierarchical Deterministic Wallets
 - BIP39 Mnemonic code
-- ECDSA signing/verifying (only hardcoded secp256k1 curve,
+- ECDSA signing/verifying (supports secp256k1 and nist256p1 curves,
   uses RFC6979 for deterministic signatures)
 - ECDSA public key derivation + Base58 address representation
 - HMAC-SHA256 and HMAC-SHA512

bignum.c

@@ -364,7 +364,7 @@ void bn_inverse(bignum256 *x, const bignum256 *prime)
 		//    res = old(x)^((prime-2) % 2^(i*30))
 		// get the i-th limb of prime - 2
 		limb = prime->val[i];
-		// this is not enough in general but fine for secp256k1 because prime->val[0] > 1
+		// this is not enough in general but fine for secp256k1 & nist256p1 because prime->val[0] > 1
 		if (i == 0) limb -= 2;
 		for (j = 0; j < 30; j++) {
 			// invariants:

tools/mktable.c

@@ -6,9 +6,9 @@
 #include "rand.h"
 
 /*
- * This program prints the contents of the secp256k1_cp array.
- * The entry secp256k1_cp[i][j] contains the number (2*j+1)*16^i*G,
- * where G is the generator of secp256k1.
+ * This program prints the contents of the ecdsa_curve.cp array.
+ * The entry cp[i][j] contains the number (2*j+1)*16^i*G,
+ * where G is the generator of the specified elliptic curve.
  */
 int main(int argc, char **argv) {
 	int i,j,k;