Implement ecdsa_get_ethereum_pubkeyhash()

ecdsa.c

@@ -36,6 +36,9 @@
 #include "base58.h"
 #include "macros.h"
 #include "secp256k1.h"
+#if USE_ETHEREUM
+#include "sha3.h"
+#endif
 
 // Set cp2 = cp1
 void point_copy(const curve_point *cp1, curve_point *cp2)
@@ -850,6 +853,27 @@ void ecdsa_get_pubkeyhash(const uint8_t *pub_key, uint8_t *pubkeyhash)
 	MEMSET_BZERO(h, sizeof(h));
 }
 
+#if USE_ETHEREUM
+int ecdsa_get_ethereum_pubkeyhash(const uint8_t *pub_key, uint8_t *pubkeyhash)
+{
+	uint8_t h[65];
+	SHA3_CTX ctx;
+
+	if (!ecdsa_uncompress_pubkey(&secp256k1, pub_key, h)) {
+		return 0;
+	}
+
+	sha3_256_Init(&ctx);
+	sha3_Update(&ctx, h + 1, 64);
+	keccak_Final(&ctx, h);
+
+	// least significant 160 bits
+	memcpy(pubkeyhash, h + 12, 20);
+
+	return 1;
+}
+#endif
+
 void ecdsa_get_address_raw(const uint8_t *pub_key, uint8_t version, uint8_t *addr_raw)
 {
 	addr_raw[0] = version;

ecdsa.h

@@ -66,6 +66,7 @@ int ecdsa_sign_digest(const ecdsa_curve *curve, const uint8_t *priv_key, const u
 void ecdsa_get_public_key33(const ecdsa_curve *curve, const uint8_t *priv_key, uint8_t *pub_key);
 void ecdsa_get_public_key65(const ecdsa_curve *curve, const uint8_t *priv_key, uint8_t *pub_key);
 void ecdsa_get_pubkeyhash(const uint8_t *pub_key, uint8_t *pubkeyhash);
+int ecdsa_get_ethereum_pubkeyhash(const uint8_t *pub_key, uint8_t *pubkeyhash);
 void ecdsa_get_address_raw(const uint8_t *pub_key, uint8_t version, uint8_t *addr_raw);
 void ecdsa_get_address(const uint8_t *pub_key, uint8_t version, char *addr, int addrsize);
 void ecdsa_get_wif(const uint8_t *priv_key, uint8_t version, char *wif, int wifsize);

options.h

@@ -56,9 +56,14 @@
 #define BIP39_CACHE_SIZE 4
 #endif
 
+// support Ethereum operations
+#ifndef USE_ETHEREUM
+#define USE_ETHEREUM 0
+#endif
+
 // support Keccak hashing
 #ifndef USE_KECCAK
-#define USE_KECCAK 0
+#define USE_KECCAK USE_ETHEREUM
 #endif
 
 #endif