3 files changed, 16 insertions, 0 deletions
diff --git a/libcmix-crypto/elgamal/elgamal.c b/libcmix-crypto/elgamal/elgamal.c
index 1525618..7eea0f3 100644
--- a/libcmix-crypto/elgamal/elgamal.c
+++ b/libcmix-crypto/elgamal/elgamal.c
@@ -10,6 +10,7 @@ struct Api get_elgamal_implementation()
 		.element_to_array = elgamal_element_to_array,
 		.free_buffer = elgamal_free_buffer,
 		.array_to_element = elgamal_array_to_element,
+		.get_pub_key_hash = elgamal_get_pub_key_hash,
 		.get_group_element = elgamal_get_group_element,
 		.get_group_element_array_size = elgamal_get_group_element_array_size,
 		.free_group_element = elgamal_delete_group_element,
diff --git a/libcmix-crypto/elgamal/elgamal.h b/libcmix-crypto/elgamal/elgamal.h
index 1fcb044..1054e3e 100644
--- a/libcmix-crypto/elgamal/elgamal.h
+++ b/libcmix-crypto/elgamal/elgamal.h
@@ -22,6 +22,8 @@ extern BufferDeleter elgamal_free_buffer;
 
 extern ArrayToElement elgamal_array_to_element;
 
+extern PubKeyHashGetter elgamal_get_pub_key_hash;
+
 extern GroupElementGetter elgamal_get_group_element;
 
 extern GroupElementDeleter elgamal_delete_group_element;
diff --git a/libcmix-crypto/elgamal/gcrypt/gcrypt_elgamal.c b/libcmix-crypto/elgamal/gcrypt/gcrypt_elgamal.c
index 2f48a9e..6a03fb1 100644
--- a/libcmix-crypto/elgamal/gcrypt/gcrypt_elgamal.c
+++ b/libcmix-crypto/elgamal/gcrypt/gcrypt_elgamal.c
@@ -129,6 +129,18 @@ void* gcrypt_elgamal_array_to_element(char const* buffer, size_t len, bool secur
 	return mpi;
 }
 
+void gcrypt_elgamal_get_pub_key_hash(char** buffer, size_t* len, GroupElement const pub) {
+	gcry_sexp_t pubkey;
+	gcry_error_t error;
+	size_t err_off;
+	
+	error = gcry_sexp_build(&pubkey, &err_off, "(public-key (elg (p %M) (g %M) (y %M)))", p, g, (gcry_mpi_t) pub);
+	check(error);
+	
+	*buffer = (char*) gcry_pk_get_keygrip(pubkey, NULL);
+	*len = 20;
+}
+
 void* gcrypt_elgamal_get_group_element(bool secure) {
 	size_t parse_error_offset;
 	gcry_error_t error;
@@ -284,6 +296,7 @@ KeyPairDeleter elgamal_delete_keypair = &gcrypt_elgamal_delete_keypair;
 ElementToArray elgamal_element_to_array = &gcrypt_elgamal_element_to_array;
 BufferDeleter elgamal_free_buffer = &gcrypt_elgamal_free_buffer;
 ArrayToElement elgamal_array_to_element = &gcrypt_elgamal_array_to_element;
+PubKeyHashGetter elgamal_get_pub_key_hash = &gcrypt_elgamal_get_pub_key_hash;
 GroupElementGetter elgamal_get_group_element = &gcrypt_elgamal_get_group_element;
 GroupElementDeleter elgamal_delete_group_element = &gcrypt_elgamal_delete_group_element;
 KeyExchangeValueGetter elgamal_get_key_exchange_value = &gcrypt_elgamal_get_key_exchange_value;