lib: fix prefix list mask length check

Implement the restriction from the old CLI to northbound.

Signed-off-by: Rafael Zalamena <rzalamena@opensourcerouting.org>

diff --git a/lib/filter_nb.c b/lib/filter_nb.c
index e823c150fa2ae4e83b473baf17112bc91b04b665..46ea71aeca4de428808158688a0c7fcd16479a18 100644 (file)
--- a/lib/filter_nb.c
+++ b/lib/filter_nb.c
@@ -39,6 +39,65 @@ ipv4_network_addr(in_addr_t hostaddr, int masklen)
        return hostaddr & mask.s_addr;
 }
 
+static enum nb_error
+prefix_list_length_validate(const struct lyd_node *dnode)
+{
+       int type = yang_dnode_get_enum(dnode, "../../type");
+       const char *xpath_le = NULL, *xpath_ge = NULL;
+       struct prefix p;
+       uint8_t le, ge;
+
+       if (type == 0 /* ipv4 */) {
+               yang_dnode_get_prefix(&p, dnode, "../ipv4-prefix");
+               xpath_le = "../ipv4-prefix-length-lesser-or-equal";
+               xpath_ge = "../ipv4-prefix-length-greater-or-equal";
+       } else {
+               yang_dnode_get_prefix(&p, dnode, "../ipv6-prefix");
+               xpath_le = "../ipv6-prefix-length-lesser-or-equal";
+               xpath_ge = "../ipv6-prefix-length-greater-or-equal";
+       }
+
+       /*
+        * Check rule:
+        * prefix length <= le.
+        */
+       if (yang_dnode_exists(dnode, xpath_le)) {
+               le = yang_dnode_get_uint8(dnode, xpath_le);
+               if (p.prefixlen > le)
+                       goto log_and_fail;
+
+       }
+
+       /*
+        * Check rule:
+        * prefix length < ge.
+        */
+       if (yang_dnode_exists(dnode, xpath_ge)) {
+               ge = yang_dnode_get_uint8(dnode, xpath_ge);
+               if (p.prefixlen >= ge)
+                       goto log_and_fail;
+       }
+
+       /*
+        * Check rule:
+        * ge <= le.
+        */
+       if (yang_dnode_exists(dnode, xpath_le) &&
+           yang_dnode_exists(dnode, xpath_ge)) {
+               le = yang_dnode_get_uint8(dnode, xpath_le);
+               ge = yang_dnode_get_uint8(dnode, xpath_ge);
+               if (ge > le)
+                       goto log_and_fail;
+       }
+
+       return NB_OK;
+
+  log_and_fail:
+       zlog_info("prefix-list: invalid prefix range for %pFX: "
+                 "Make sure that mask length < ge <= le", &p);
+       return NB_ERR_VALIDATION;
+}
+
 /*
  * XPath: /frr-filter:lib/access-list-legacy
  */
@@ -857,6 +916,10 @@ static int lib_prefix_list_entry_ipv4_prefix_length_greater_or_equal_modify(
 {
        struct prefix_list_entry *ple;
 
+       if (args->event == NB_EV_VALIDATE &&
+           prefix_list_length_validate(args->dnode) != NB_OK)
+               return NB_ERR_VALIDATION;
+
        if (args->event != NB_EV_APPLY)
                return NB_OK;
 
@@ -888,6 +951,10 @@ static int lib_prefix_list_entry_ipv4_prefix_length_lesser_or_equal_modify(
 {
        struct prefix_list_entry *ple;
 
+       if (args->event == NB_EV_VALIDATE &&
+           prefix_list_length_validate(args->dnode) != NB_OK)
+               return NB_ERR_VALIDATION;
+
        if (args->event != NB_EV_APPLY)
                return NB_OK;