EAP-pwd: Fix Prep in EAP-pwd-ID/Response when EAP_PWD_PREP_MS is used

Fix the pre-processing field in the response when EAP_PWD_PREP_MS is
being used. This fixes interoperability with EAP-pwd servers that
validate the Prep field in EAP-pwd-ID/Response when the RFC2759
(PasswordHashHash) pre-processing is used.

Signed-off-by: Brian Candler <B.Candler@pobox.com>

src/eap_peer/eap_pwd.c

@@ -345,7 +345,7 @@ eap_pwd_perform_id_exchange(struct eap_sm *sm, struct eap_pwd_data *data,
 	wpabuf_put_u8(data->outbuf, EAP_PWD_DEFAULT_RAND_FUNC);
 	wpabuf_put_u8(data->outbuf, EAP_PWD_DEFAULT_PRF);
 	wpabuf_put_data(data->outbuf, id->token, sizeof(id->token));
-	wpabuf_put_u8(data->outbuf, EAP_PWD_PREP_NONE);
+	wpabuf_put_u8(data->outbuf, id->prep);
 	wpabuf_put_data(data->outbuf, data->id_peer, data->id_peer_len);
 
 	eap_pwd_state(data, PWD_Commit_Req);