Fix incorrect creation of classifier entries for macip ACL

The is_ip6 flag was incorrectly set during classifier
table creation phase, which intermittently caused the mismatch
between the mask value and the match values, resulting
in dropped packets. Fix that.

Also get rid of the magic numbers in that part of the code.

Change-Id: I0606561e6b07e70a1aa733746b56ed0e91752c94
Signed-off-by: Andrew Yourtchenko <ayourtch@gmail.com>

1 files changed, 31 insertions, 9 deletions

diff --git a/plugins/acl-plugin/acl/acl.c b/plugins/acl-plugin/acl/acl.c
index 50eca8802c9..7b95152cbf3 100644
--- a/plugins/acl-plugin/acl/acl.c
+++ b/plugins/acl-plugin/acl/acl.c
@@ -13,6 +13,8 @@
  * limitations under the License.
  */
 
+#include <stddef.h>
+
 #include <vnet/vnet.h>
 #include <vnet/plugin/plugin.h>
 #include <acl/acl.h>
@@ -1080,6 +1082,16 @@ match_type_compare (macip_match_type_t * m1, macip_match_type_t * m2)
   return match_type_metric (m1) - match_type_metric (m2);
 }
 
+/* Get the offset of L3 source within ethernet packet */
+static int
+get_l3_src_offset(int is6)
+{
+  if(is6)
+    return (sizeof(ethernet_header_t) + offsetof(ip6_header_t, src_address));
+  else
+    return (sizeof(ethernet_header_t) + offsetof(ip4_header_t, src_address));
+}
+
 static int
 macip_create_classify_tables (acl_main_t * am, u32 macip_acl_index)
 {
@@ -1118,8 +1130,8 @@ macip_create_classify_tables (acl_main_t * am, u32 macip_acl_index)
   vec_foreach (mt, mvec)
   {
     int mask_len;
-    int is6 = a->rules[i].is_ipv6;
-    int l3_src_offs = is6 ? 22 : 26;	/* See the ascii art packet format above to verify these */
+    int is6 = mt->is_ipv6;
+    int l3_src_offs = get_l3_src_offset(is6);
     memset (mask, 0, sizeof (mask));
     memcpy (&mask[6], mt->mac_mask, 6);
     for (i = 0; i < (mt->prefix_len / 8); i++)
@@ -1131,7 +1143,12 @@ macip_create_classify_tables (acl_main_t * am, u32 macip_acl_index)
 	mask[l3_src_offs + (mt->prefix_len / 8)] =
 	  0xff - ((1 << (8 - mt->prefix_len % 8)) - 1);
       }
-    mask_len = ((l3_src_offs + (mt->prefix_len / 8)) / 16 + 1) * 16;
+    /*
+     * Round-up the number of bytes needed to store the prefix,
+     * and round up the number of vectors too
+     */
+    mask_len = ((l3_src_offs + ((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->table_index,
 				1);
@@ -1147,7 +1164,7 @@ macip_create_classify_tables (acl_main_t * am, u32 macip_acl_index)
       u32 action = 0;
       u32 metadata = 0;
       int is6 = a->rules[i].is_ipv6;
-      int l3_src_offs = is6 ? 22 : 26;	/* See the ascii art packet format above to verify these */
+      int l3_src_offs = get_l3_src_offset(is6);
       memset (mask, 0, sizeof (mask));
       memcpy (&mask[6], a->rules[i].src_mac, 6);
       if (is6)
@@ -1219,8 +1236,10 @@ macip_acl_add_list (u32 count, vl_api_macip_acl_rule_t rules[],
       r->is_ipv6 = rules[i].is_ipv6;
       memcpy (&r->src_mac, rules[i].src_mac, 6);
       memcpy (&r->src_mac_mask, rules[i].src_mac_mask, 6);
-
-      memcpy (&r->src_ip_addr, rules[i].src_ip_addr, sizeof (r->src_ip_addr));
+      if(rules[i].is_ipv6)
+        memcpy (&r->src_ip_addr.ip6, rules[i].src_ip_addr, 16);
+      else
+        memcpy (&r->src_ip_addr.ip4, rules[i].src_ip_addr, 4);
       r->src_prefixlen = rules[i].src_ip_prefix_len;
     }
 
@@ -1664,9 +1683,12 @@ send_macip_acl_details (acl_main_t * am, unix_shared_memory_queue_t * q,
 	  memcpy (rules[i].src_mac, &r->src_mac, sizeof (r->src_mac));
 	  memcpy (rules[i].src_mac_mask, &r->src_mac_mask,
 		  sizeof (r->src_mac_mask));
-
-	  memcpy (rules[i].src_ip_addr, &r->src_ip_addr,
-		  sizeof (r->src_ip_addr));
+          if (r->is_ipv6)
+            memcpy (rules[i].src_ip_addr, &r->src_ip_addr.ip6,
+		  sizeof (r->src_ip_addr.ip6));
+          else
+            memcpy (rules[i].src_ip_addr, &r->src_ip_addr.ip4,
+		  sizeof (r->src_ip_addr.ip4));
 	  rules[i].src_ip_prefix_len = r->src_prefixlen;
 	}
     }