VPP-574: fix the MACIP ACLs blocking ARP traffic

The initial assumption was that the MACIP ACL classifier tables would be applied
after the classification of the traffic based on the ethertype, it turned out
to be untrue, but the fix in the code did not happen.

Add the ethertype to the mask, and the logic to create the ACL classifier tables
permitting the ARP ethertype with the correct payload.

Change-Id: I7c05c7893f6df8258998eed8983056c77586df81
Signed-off-by: Andrew Yourtchenko <ayourtch@gmail.com>

1 files changed, 47 insertions, 0 deletions

diff --git a/src/plugins/acl/acl.c b/src/plugins/acl/acl.c
index 8ff5a6b721c..f4db2013769 100644
--- a/src/plugins/acl/acl.c
+++ b/src/plugins/acl/acl.c
@@ -1044,6 +1044,7 @@ typedef struct
   u8 prefix_len;
   u32 count;
   u32 table_index;
+  u32 arp_table_index;
 } macip_match_type_t;
 
 static u32
@@ -1127,6 +1128,34 @@ macip_create_classify_tables (acl_main_t * am, u32 macip_acl_index)
   vec_sort_with_function (mvec, match_type_compare);
   /* Create the classifier tables */
   last_table = ~0;
+  /* First add ARP tables */
+  vec_foreach (mt, mvec)
+  {
+    int mask_len;
+    int is6 = mt->is_ipv6;
+
+    mt->arp_table_index = ~0;
+    if (!is6)
+      {
+        memset (mask, 0, sizeof (mask));
+        memcpy (&mask[6], mt->mac_mask, 6);
+        memset (&mask[12], 0xff, 2); /* ethernet protocol */
+        memcpy (&mask[14 + 8], mt->mac_mask, 6);
+
+        for (i = 0; i < (mt->prefix_len / 8); i++)
+          mask[14 + 14 + i] = 0xff;
+        if (mt->prefix_len % 8)
+          mask[14 + 14 + (mt->prefix_len / 8)] = 0xff - ((1 << (8 - mt->prefix_len % 8)) - 1);
+
+        mask_len = ((14 + 14 + ((mt->prefix_len+7) / 8) +
+                (sizeof (u32x4)-1))/sizeof(u32x4)) * sizeof (u32x4);
+        acl_classify_add_del_table_small (cm, mask, mask_len, last_table,
+                               (~0 == last_table) ? 0 : ~0, &mt->arp_table_index,
+                               1);
+        last_table = mt->arp_table_index;
+      }
+  }
+  /* Now add IP[46] tables */
   vec_foreach (mt, mvec)
   {
     int mask_len;
@@ -1167,13 +1196,18 @@ macip_create_classify_tables (acl_main_t * am, u32 macip_acl_index)
       int l3_src_offs = get_l3_src_offset(is6);
       memset (mask, 0, sizeof (mask));
       memcpy (&mask[6], a->rules[i].src_mac, 6);
+      memset (&mask[12], 0xff, 2); /* ethernet protocol */
       if (is6)
 	{
 	  memcpy (&mask[l3_src_offs], &a->rules[i].src_ip_addr.ip6, 16);
+	  mask[12] = 0x86;
+	  mask[13] = 0xdd;
 	}
       else
 	{
 	  memcpy (&mask[l3_src_offs], &a->rules[i].src_ip_addr.ip4, 4);
+	  mask[12] = 0x08;
+	  mask[13] = 0x00;
 	}
       match_type_index =
 	macip_find_match_type (mvec, a->rules[i].src_mac_mask,
@@ -1183,6 +1217,19 @@ macip_create_classify_tables (acl_main_t * am, u32 macip_acl_index)
       vnet_classify_add_del_session (cm, mvec[match_type_index].table_index,
 				     mask, a->rules[i].is_permit ? ~0 : 0, i,
 				     0, action, metadata, 1);
+      /* add ARP table entry too */
+      if (!is6 && (mvec[match_type_index].arp_table_index != ~0))
+        {
+          memset (mask, 0, sizeof (mask));
+          memcpy (&mask[6], a->rules[i].src_mac, 6);
+          mask[12] = 0x08;
+          mask[13] = 0x06;
+          memcpy (&mask[14 + 8], a->rules[i].src_mac, 6);
+          memcpy (&mask[14 + 14], &a->rules[i].src_ip_addr.ip4, 4);
+          vnet_classify_add_del_session (cm, mvec[match_type_index].arp_table_index,
+                                    mask, a->rules[i].is_permit ? ~0 : 0, i,
+                                    0, action, metadata, 1);
+        }
     }
   return 0;
 }