vnet/vnet/l2/l2_input.h

   1 /*
   2  * l2_input.h : layer 2 input packet processing
   3  *
   4  * Copyright (c) 2013 Cisco and/or its affiliates.
   5  * Licensed under the Apache License, Version 2.0 (the "License");
   6  * you may not use this file except in compliance with the License.
   7  * You may obtain a copy of the License at:
   8  *
   9  *     http://www.apache.org/licenses/LICENSE-2.0
  10  *
  11  * Unless required by applicable law or agreed to in writing, software
  12  * distributed under the License is distributed on an "AS IS" BASIS,
  13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14  * See the License for the specific language governing permissions and
  15  * limitations under the License.
  16  */
  17
  18 #ifndef included_vnet_l2_input_h
  19 #define included_vnet_l2_input_h
  20
  21 #include <vlib/vlib.h>
  22 #include <vnet/vnet.h>
  23 #include <vnet/l2/l2_bd.h>
  24 #include <vnet/ethernet/packet.h>
  25 #include <vnet/ip/ip.h>
  26
  27 // Per-subinterface L2 feature configuration
  28
  29 typedef struct {
  30
  31   union {
  32     u16 bd_index;                 // bridge domain id
  33     u32 output_sw_if_index;    // for xconnect
  34   };
  35
  36   // Interface mode. If both are 0, this interface is in L3 mode
  37   u8  xconnect;
  38   u8  bridge;
  39
  40   // this is the bvi interface for the bridge-domain
  41   u8  bvi;
  42
  43   // config for which input features are configured on this interface
  44   u32 feature_bitmap;
  45
  46   // some of these flags are also in the feature bitmap
  47   u8  learn_enable;
  48   u8  fwd_enable;
  49   u8  flood_enable;
  50
  51   // split horizon group
  52   u8  shg;
  53
  54 } l2_input_config_t;
  55
  56
  57 typedef struct {
  58
  59   // Next nodes for the feature bitmap
  60   u32 feat_next_node_index[32];
  61
  62   /* config vector indexed by sw_if_index */
  63   l2_input_config_t *configs;
  64
  65   /* bridge domain config vector indexed by BD ID */
  66   l2_bridge_domain_t *bd_configs;
  67
  68   /* convenience variables */
  69   vlib_main_t * vlib_main;
  70   vnet_main_t * vnet_main;
  71 } l2input_main_t;
  72
  73 extern l2input_main_t l2input_main;
  74
  75 static_always_inline l2_bridge_domain_t *
  76 l2input_bd_config_from_index (l2input_main_t * l2im, u32 bd_index)
  77 {
  78     l2_bridge_domain_t * bd_config;
  79
  80     bd_config = vec_elt_at_index (l2im->bd_configs, bd_index);
  81     return bd_is_valid (bd_config) ? bd_config : NULL;
  82 }
  83
  84 // L2 input features
  85
  86 // Mappings from feature ID to graph node name
  87 #define foreach_l2input_feat \
  88  _(DROP,          "feature-bitmap-drop")        \
  89  _(CLASSIFY,      "l2-classify")                \
  90  _(XCONNECT,      "l2-output")                  \
  91  _(IPIW,          "feature-bitmap-drop")        \
  92  _(FLOOD,         "l2-flood")                   \
  93  _(ARP_TERM,      "arp-term-l2bd")              \
  94  _(UU_FLOOD,      "l2-flood")                   \
  95  _(FWD,           "l2-fwd")                     \
  96  _(LEARN,         "l2-learn")                   \
  97  _(VTR,           "l2-input-vtr")               \
  98  _(VPATH,         "vpath-input-l2")             \
  99  _(CTRL_PKT,      "feature-bitmap-drop")        \
 100  _(L2PT,          "feature-bitmap-drop")        \
 101  _(IGMP_SNOOP,    "feature-bitmap-drop")        \
 102  _(MLD_SNOOP,     "feature-bitmap-drop")        \
 103  _(DHCP_SNOOP,    "feature-bitmap-drop")        \
 104  _(DAI,           "feature-bitmap-drop")        \
 105  _(IPSG,          "feature-bitmap-drop")        \
 106  _(ACL,           "l2-input-acl")               \
 107  _(QOS,           "feature-bitmap-drop")        \
 108  _(CFM,           "feature-bitmap-drop")        \
 109  _(SPAN,          "feature-bitmap-drop")
 110
 111 // Feature bitmap positions
 112 typedef enum {
 113 #define _(sym,str) L2INPUT_FEAT_##sym##_BIT,
 114   foreach_l2input_feat
 115 #undef _
 116   L2INPUT_N_FEAT,
 117 } l2input_feat_t;
 118
 119 // Feature bit masks
 120 typedef enum {
 121 #define _(sym,str) L2INPUT_FEAT_##sym = (1<<L2INPUT_FEAT_##sym##_BIT),
 122   foreach_l2input_feat
 123 #undef _
 124 } l2input_feat_masks_t;
 125
 126 // Return an array of strings containing graph node names of each feature
 127 char **l2input_get_feat_names(void);
 128
 129
 130 static_always_inline u8 bd_feature_flood (l2_bridge_domain_t * bd_config)
 131 {
 132     return ((bd_config->feature_bitmap & L2INPUT_FEAT_FLOOD) ==
 133             L2INPUT_FEAT_FLOOD);
 134 }
 135
 136 static_always_inline u8 bd_feature_uu_flood (l2_bridge_domain_t * bd_config)
 137 {
 138     return ((bd_config->feature_bitmap & L2INPUT_FEAT_UU_FLOOD) ==
 139             L2INPUT_FEAT_UU_FLOOD);
 140 }
 141
 142 static_always_inline u8 bd_feature_forward (l2_bridge_domain_t * bd_config)
 143 {
 144     return ((bd_config->feature_bitmap & L2INPUT_FEAT_FWD) ==
 145             L2INPUT_FEAT_FWD);
 146 }
 147
 148 static_always_inline u8 bd_feature_learn (l2_bridge_domain_t * bd_config)
 149 {
 150     return ((bd_config->feature_bitmap & L2INPUT_FEAT_LEARN) ==
 151             L2INPUT_FEAT_LEARN);
 152 }
 153
 154 static_always_inline u8 bd_feature_arp_term (l2_bridge_domain_t * bd_config)
 155 {
 156     return ((bd_config->feature_bitmap & L2INPUT_FEAT_ARP_TERM) ==
 157             L2INPUT_FEAT_ARP_TERM);
 158 }
 159
 160 // Masks for eliminating features that do not apply to a packet
 161
 162 #define IP4_FEAT_MASK  ~(L2INPUT_FEAT_CTRL_PKT    | \
 163                          L2INPUT_FEAT_MLD_SNOOP   | \
 164                          L2INPUT_FEAT_L2PT        | \
 165                          L2INPUT_FEAT_CFM         | \
 166                          L2INPUT_FEAT_DAI)
 167
 168 #define IP6_FEAT_MASK  ~(L2INPUT_FEAT_CTRL_PKT    | \
 169                          L2INPUT_FEAT_IGMP_SNOOP  | \
 170                          L2INPUT_FEAT_L2PT        | \
 171                          L2INPUT_FEAT_CFM         | \
 172                          L2INPUT_FEAT_DAI)
 173
 174 #define IP_UDP_TCP_FEAT_MASK  ~(L2INPUT_FEAT_CTRL_PKT   | \
 175                                 L2INPUT_FEAT_L2PT       | \
 176                                 L2INPUT_FEAT_IGMP_SNOOP | \
 177                                 L2INPUT_FEAT_MLD_SNOOP  | \
 178                                 L2INPUT_FEAT_DHCP_SNOOP | \
 179                                 L2INPUT_FEAT_CFM        | \
 180                                 L2INPUT_FEAT_DAI)
 181
 182 #define MPLS_FEAT_MASK  ~(L2INPUT_FEAT_CTRL_PKT   | \
 183                           L2INPUT_FEAT_L2PT       | \
 184                           L2INPUT_FEAT_IGMP_SNOOP | \
 185                           L2INPUT_FEAT_MLD_SNOOP  | \
 186                           L2INPUT_FEAT_DHCP_SNOOP | \
 187                           L2INPUT_FEAT_CFM        | \
 188                           L2INPUT_FEAT_DAI)
 189
 190
 191 // Get a pointer to the config for the given interface
 192 l2_input_config_t * l2input_intf_config (u32 sw_if_index);
 193
 194 // Enable (or disable) the feature in the bitmap for the given interface
 195 u32 l2input_intf_bitmap_enable (u32 sw_if_index,
 196                                  u32 feature_bitmap,
 197                                  u32 enable);
 198
 199
 200 #define MODE_L3        0
 201 #define MODE_L2_BRIDGE 1
 202 #define MODE_L2_XC     2
 203 #define MODE_L2_CLASSIFY 3
 204
 205 #define MODE_ERROR_ETH        1
 206 #define MODE_ERROR_BVI_DEF    2
 207
 208 u32 set_int_l2_mode (vlib_main_t * vm,
 209                      vnet_main_t * vnet_main,
 210                      u32 mode,
 211                      u32 sw_if_index,
 212                      u32 bd_index,
 213                      u32 bvi,
 214                      u32 shg,
 215                      u32 xc_sw_if_index);
 216
 217 static inline void
 218 vnet_update_l2_len (vlib_buffer_t * b)
 219 {
 220   ethernet_header_t * eth;
 221   u16 ethertype;
 222
 223   /* point at currrent l2 hdr */
 224   eth = vlib_buffer_get_current (b);
 225
 226   /*
 227    * l2-output pays no attention to this
 228    * but the tag push/pop code on an l2 subif needs it.
 229    *
 230    * Determine l2 header len, check for up to 2 vlans
 231    */
 232   vnet_buffer(b)->l2.l2_len = sizeof(ethernet_header_t);
 233   ethertype = clib_net_to_host_u16(eth->type);
 234   if ((ethertype == ETHERNET_TYPE_VLAN) ||
 235       (ethertype == ETHERNET_TYPE_DOT1AD) ||
 236       (ethertype == ETHERNET_TYPE_VLAN_9100) ||
 237       (ethertype == ETHERNET_TYPE_VLAN_9200)) {
 238     ethernet_vlan_header_t * vlan;
 239     vnet_buffer(b)->l2.l2_len += sizeof (*vlan);
 240     vlan = (void *) (eth+1);
 241     ethertype = clib_net_to_host_u16 (vlan->type);
 242     if (ethertype == ETHERNET_TYPE_VLAN) {
 243       vnet_buffer(b)->l2.l2_len += sizeof (*vlan);
 244     }
 245   }
 246 }
 247
 248 /*
 249  * Compute flow hash of an ethernet packet, use 5-tuple hash if L3 packet
 250  * is ip4 or ip6. Otherwise hash on smac/dmac/etype.
 251  * The vlib buffer current pointer is expected to be at ethernet header
 252  * and vnet l2.l2_len is exppected to be setup already.
 253  */
 254 static inline u32 vnet_l2_compute_flow_hash (vlib_buffer_t *b)
 255 {
 256   ethernet_header_t * eh = vlib_buffer_get_current(b);
 257   u8 * l3h = (u8 *)eh + vnet_buffer(b)->l2.l2_len;
 258   u16 ethertype = clib_net_to_host_u16(*(u16 *)(l3h - 2));
 259
 260   if (ethertype == ETHERNET_TYPE_IP4)
 261     return ip4_compute_flow_hash((ip4_header_t *) l3h, IP_FLOW_HASH_DEFAULT);
 262   else if (ethertype == ETHERNET_TYPE_IP6)
 263     return ip6_compute_flow_hash((ip6_header_t *) l3h, IP_FLOW_HASH_DEFAULT);
 264   else
 265     {
 266       u32 a, b, c;
 267       u32 * ap = (u32 *) &eh->dst_address[2];
 268       u32 * bp = (u32 *) &eh->src_address[2];
 269       a = * ap;
 270       b = * bp;
 271       c = ethertype;
 272       hash_v3_mix32 (a, b, c);
 273       hash_v3_finalize32 (a, b, c);
 274       return c;
 275     }
 276 }
 277
 278 #endif
 279