diff -r 4b55f05f4e00 -r a297c2e28fa1 libidav/utils.c
--- a/libidav/utils.c	Sat Mar 19 18:49:36 2016 +0100
+++ b/libidav/utils.c	Sun Mar 20 11:27:31 2016 +0100
@@ -52,9 +52,10 @@
 #include <openssl/buffer.h>
 #include <openssl/rand.h>
 
+#include "webdav.h"
 #include "utils.h"
 #include "crypto.h"
-#include "webdav.h"
+#include "session.h"
 
 static size_t extractval(sstr_t str, char *result, char delim) {
     size_t n = 0;
@@ -505,7 +506,10 @@
 char* util_encrypt_str(DavSession *sn, char *str, char *key) {
     DavKey *k = dav_context_get_key(sn->context, key);
     if(!k) {
-        // TODO: session error
+        sn->error = DAV_ERROR;
+        sstr_t err = ucx_sprintf("Key %s not found", key);
+        dav_session_set_errstr(sn, err.ptr);
+        free(err.ptr);
         return NULL;
     }
     
@@ -522,7 +526,10 @@
 char* util_decrypt_str(DavSession *sn, char *str, char *key) {
     DavKey *k = dav_context_get_key(sn->context, key);
     if(!k) {
-        // TODO: session error
+        sn->error = DAV_ERROR;
+        sstr_t err = ucx_sprintf("Key %s not found", key);
+        dav_session_set_errstr(sn, err.ptr);
+        free(err.ptr);
         return NULL;
     }