diff --git a/libckteec/include/pkcs11.h b/libckteec/include/pkcs11.h
index 948738a6..bfd76614 100644
--- a/libckteec/include/pkcs11.h
+++ b/libckteec/include/pkcs11.h
@@ -240,6 +240,7 @@ typedef CK_KEY_TYPE *CK_KEY_TYPE_PTR;
 #define CKK_SHA384_HMAC			0x02c
 #define CKK_SHA512_HMAC			0x02d
 #define CKK_SHA224_HMAC			0x02e
+#define CKK_EC_EDWARDS			0x040 /* PKCS#11 v3.1-cs01 */
 
 /*
  * Certificates
@@ -351,6 +352,8 @@ typedef CK_MECHANISM_TYPE *CK_MECHANISM_TYPE_PTR;
 #define CKM_ECMQV_DERIVE		0x01052
 #define CKM_ECDH_AES_KEY_WRAP		0x01053
 #define CKM_RSA_AES_KEY_WRAP		0x01054
+#define CKM_EC_EDWARDS_KEY_PAIR_GEN	0x01055
+#define CKM_EDDSA			0x01057
 #define CKM_AES_KEY_GEN			0x01080
 #define CKM_AES_ECB			0x01081
 #define CKM_AES_CBC			0x01082
@@ -492,6 +495,15 @@ struct CK_GCM_PARAMS {
 	CK_ULONG		ulTagBits;
 };
 
+/* EdDSA (RFC 8032) */
+typedef struct CK_EDDSA_PARAMS {
+	CK_BYTE phFlag;
+	CK_ULONG ulContextDataLen;
+	CK_BYTE_PTR pContextData;
+} CK_EDDSA_PARAMS;
+
+typedef CK_EDDSA_PARAMS *CK_EDDSA_PARAMS_PTR;
+
 /* AES CCM parameters */
 typedef struct CK_CCM_PARAMS CK_CCM_PARAMS;
 typedef struct CK_CCM_PARAMS *CK_CCM_PARAMS_PTR;
diff --git a/libckteec/include/pkcs11_ta.h b/libckteec/include/pkcs11_ta.h
index 36cc7b44..063198b9 100644
--- a/libckteec/include/pkcs11_ta.h
+++ b/libckteec/include/pkcs11_ta.h
@@ -1279,6 +1279,7 @@ enum pkcs11_mechanism_id {
 	PKCS11_CKM_ECMQV_DERIVE			= 0x01052,
 	PKCS11_CKM_ECDH_AES_KEY_WRAP		= 0x01053,
 	PKCS11_CKM_RSA_AES_KEY_WRAP		= 0x01054,
+	PKCS11_CKM_EDDSA			= 0x01057,
 	PKCS11_CKM_AES_KEY_GEN			= 0x01080,
 	PKCS11_CKM_AES_ECB			= 0x01081,
 	PKCS11_CKM_AES_CBC			= 0x01082,
diff --git a/libckteec/src/serialize_ck.c b/libckteec/src/serialize_ck.c
index 07382a5a..d1411ece 100644
--- a/libckteec/src/serialize_ck.c
+++ b/libckteec/src/serialize_ck.c
@@ -582,6 +582,31 @@ static CK_RV serialize_mecha_rsa_oaep_param(struct serializer *obj,
 				params->ulSourceDataLen);
 }
 
+static CK_RV serialize_mecha_eddsa(struct serializer *obj,
+				   CK_MECHANISM_PTR mecha)
+{
+	CK_RV rv = CKR_GENERAL_ERROR;
+	CK_EDDSA_PARAMS *params = mecha->pParameter;
+
+	rv = serialize_32b(obj, obj->type);
+	if (rv)
+		return rv;
+
+	rv = serialize_32b(obj, 2 * sizeof(uint32_t) + params->ulContextDataLen);
+	if (rv)
+		return rv;
+
+	rv = serialize_32b(obj, params->phFlag);
+	if (rv)
+		return rv;
+
+	rv = serialize_32b(obj, params->ulContextDataLen);
+	if (rv)
+		return rv;
+
+	return serialize_buffer(obj, params->pContextData, params->ulContextDataLen);
+}
+
 static CK_RV serialize_mecha_mac_general_param(struct serializer *obj,
 					       CK_MECHANISM_PTR mecha)
 {
@@ -649,6 +674,7 @@ CK_RV serialize_ck_mecha_params(struct serializer *obj,
 	case CKM_SHA384_HMAC:
 	case CKM_SHA512_HMAC:
 	case CKM_EC_KEY_PAIR_GEN:
+	case CKM_EC_EDWARDS_KEY_PAIR_GEN:
 	case CKM_ECDSA:
 	case CKM_ECDSA_SHA1:
 	case CKM_ECDSA_SHA224:
@@ -673,6 +699,9 @@ CK_RV serialize_ck_mecha_params(struct serializer *obj,
 
 		return serialize_32b(obj, 0);
 
+	case CKM_EDDSA:
+		return serialize_mecha_eddsa(obj, &mecha);
+
 	case CKM_AES_CBC:
 	case CKM_AES_CBC_PAD:
 	case CKM_AES_CTS: