sysdb: try dealing with binary-content attributes

https://fedorahosted.org/sssd/ticket/1818

I have here a LDAP user entry which has this attribute

	loginAllowedTimeMap::
	 AAAAAAAAAP///38AAP///38AAP///38AAP///38AAP///38AAAAAAAAA

In the function sysdb_attrs_add_string(), called from
sdap_attrs_add_ldap_attr(), strlen() is called on this blob, which is
the wrong thing to do. The result of strlen is then used to populate
the .v_length member of a struct ldb_val - and this will set it to
zero in this case. (There is also the problem that there may not be
a '\0' at all in the blob.)

Subsequently, .v_length being 0 makes ldb_modify(), called from
sysdb_set_entry_attr(), return LDB_ERR_INVALID_ATTRIBUTE_SYNTAX. End
result is that users do not get stored in the sysdb, and programs like
`id` or `getent ...` show incomplete information.

The bug was encountered with sssd-1.8.5. sssd-1.5.11 seemed to behave
fine, but that may not mean that is the absolute lower boundary of
introduction of the problem.

1 files changed, 3 insertions, 5 deletions

diff --git a/src/providers/ldap/sdap.c b/src/providers/ldap/sdap.c
index 371121b2c..dba4e41db 100644
--- a/src/providers/ldap/sdap.c
+++ b/src/providers/ldap/sdap.c
@@ -343,7 +343,6 @@ errno_t sdap_parse_deref(TALLOC_CTX *mem_ctx,
     const char **ocs;
     struct sdap_attr_map *map;
     int num_attrs;
-    struct ldb_val v;
     int ret, i, a, mi;
     const char *name;
     size_t len;
@@ -474,10 +473,9 @@ errno_t sdap_parse_deref(TALLOC_CTX *mem_ctx,
             for (i=0; dval->vals[i].bv_val; i++) {
                 DEBUG(9, ("Dereferenced attribute value: %s\n",
                           dval->vals[i].bv_val));
-                v.data = (uint8_t *) dval->vals[i].bv_val;
-                v.length = dval->vals[i].bv_len;
-
-                ret = sysdb_attrs_add_val(res[mi]->attrs, name, &v);
+                ret = sysdb_attrs_add_mem(res[mi]->attrs, name,
+                                          dval->vals[i].bv_val,
+                                          dval->vals[i].bv_len);
                 if (ret) goto done;
             }
         }