ofproto/tunnel.c

   1 /* Copyright (c) 2013 Nicira, Inc.
   2  *
   3  * Licensed under the Apache License, Version 2.0 (the "License");
   4  * you may not use this file except in compliance with the License.
   5  * You may obtain a copy of the License at:
   6  *
   7  *     http://www.apache.org/licenses/LICENSE-2.0
   8  *
   9  * Unless required by applicable law or agreed to in writing, software
  10  * distributed under the License is distributed on an "AS IS" BASIS,
  11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12  * See the License for the specific language governing permissions and
  13  * limitations under the License. */
  14
  15 #include <config.h>
  16 #include "tunnel.h"
  17
  18 #include <errno.h>
  19
  20 #include "byte-order.h"
  21 #include "dynamic-string.h"
  22 #include "hash.h"
  23 #include "hmap.h"
  24 #include "netdev.h"
  25 #include "odp-util.h"
  26 #include "packets.h"
  27 #include "smap.h"
  28 #include "socket-util.h"
  29 #include "tunnel.h"
  30 #include "vlog.h"
  31
  32 VLOG_DEFINE_THIS_MODULE(tunnel);
  33
  34 struct tnl_match {
  35     ovs_be64 in_key;
  36     ovs_be32 ip_src;
  37     ovs_be32 ip_dst;
  38     odp_port_t odp_port;
  39     uint32_t skb_mark;
  40     bool in_key_flow;
  41     bool ip_src_flow;
  42     bool ip_dst_flow;
  43 };
  44
  45 struct tnl_port {
  46     struct hmap_node match_node;
  47
  48     const struct ofport_dpif *ofport;
  49     unsigned int netdev_seq;
  50     struct netdev *netdev;
  51
  52     struct tnl_match match;
  53 };
  54
  55 static struct hmap tnl_match_map = HMAP_INITIALIZER(&tnl_match_map);
  56
  57 /* Returned to callers when their ofport will never be used to receive or send
  58  * tunnel traffic. Alternatively, we could ask the caller to delete their
  59  * ofport, but this would be unclean in the reconfguration case.  For the first
  60  * time, an ofproto provider would have to call ofproto_port_del() on itself.*/
  61 static struct tnl_port void_tnl_port;
  62
  63 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5);
  64 static struct vlog_rate_limit dbg_rl = VLOG_RATE_LIMIT_INIT(60, 60);
  65
  66 static struct tnl_port *tnl_find(struct tnl_match *);
  67 static struct tnl_port *tnl_find_exact(struct tnl_match *);
  68 static uint32_t tnl_hash(struct tnl_match *);
  69 static void tnl_match_fmt(const struct tnl_match *, struct ds *);
  70 static char *tnl_port_fmt(const struct tnl_port *);
  71 static void tnl_port_mod_log(const struct tnl_port *, const char *action);
  72 static const char *tnl_port_get_name(const struct tnl_port *);
  73
  74 static struct tnl_port *
  75 tnl_port_add__(const struct ofport_dpif *ofport, const struct netdev *netdev,
  76                odp_port_t odp_port, bool warn)
  77 {
  78     const struct netdev_tunnel_config *cfg;
  79     struct tnl_port *existing_port;
  80     struct tnl_port *tnl_port;
  81
  82     cfg = netdev_get_tunnel_config(netdev);
  83     ovs_assert(cfg);
  84
  85     tnl_port = xzalloc(sizeof *tnl_port);
  86     tnl_port->ofport = ofport;
  87     tnl_port->netdev = netdev_ref(netdev);
  88     tnl_port->netdev_seq = netdev_change_seq(tnl_port->netdev);
  89
  90     tnl_port->match.in_key = cfg->in_key;
  91     tnl_port->match.ip_src = cfg->ip_src;
  92     tnl_port->match.ip_dst = cfg->ip_dst;
  93     tnl_port->match.ip_src_flow = cfg->ip_src_flow;
  94     tnl_port->match.ip_dst_flow = cfg->ip_dst_flow;
  95     tnl_port->match.skb_mark = cfg->ipsec ? IPSEC_MARK : 0;
  96     tnl_port->match.in_key_flow = cfg->in_key_flow;
  97     tnl_port->match.odp_port = odp_port;
  98
  99     existing_port = tnl_find_exact(&tnl_port->match);
 100     if (existing_port) {
 101         if (warn) {
 102             struct ds ds = DS_EMPTY_INITIALIZER;
 103             tnl_match_fmt(&tnl_port->match, &ds);
 104             VLOG_WARN("%s: attempting to add tunnel port with same config as "
 105                       "port '%s' (%s)", tnl_port_get_name(tnl_port),
 106                       tnl_port_get_name(existing_port), ds_cstr(&ds));
 107             ds_destroy(&ds);
 108             free(tnl_port);
 109         }
 110         return &void_tnl_port;
 111     }
 112
 113     hmap_insert(&tnl_match_map, &tnl_port->match_node,
 114                 tnl_hash(&tnl_port->match));
 115     tnl_port_mod_log(tnl_port, "adding");
 116     return tnl_port;
 117 }
 118
 119 /* Adds 'ofport' to the module with datapath port number 'odp_port'. 'ofport's
 120  * must be added before they can be used by the module. 'ofport' must be a
 121  * tunnel. */
 122 struct tnl_port *
 123 tnl_port_add(const struct ofport_dpif *ofport, const struct netdev *netdev,
 124              odp_port_t odp_port)
 125 {
 126     return tnl_port_add__(ofport, netdev, odp_port, true);
 127 }
 128
 129 /* Checks if the tnl_port pointed to by 'tnl_portp' needs reconfiguration due
 130  * to changes in its netdev_tunnel_config.  If it does, updates 'tnl_portp' to
 131  * point to a new tnl_port and returns true.  Otherwise, returns false.
 132  * 'ofport' and 'odp_port' should be the same as would be passed to
 133  * tnl_port_add(). */
 134 bool
 135 tnl_port_reconfigure(const struct ofport_dpif *ofport,
 136                      const struct netdev *netdev, odp_port_t odp_port,
 137                      struct tnl_port **tnl_portp)
 138 {
 139     struct tnl_port *tnl_port = *tnl_portp;
 140
 141     if (tnl_port == &void_tnl_port) {
 142         *tnl_portp = tnl_port_add__(ofport, netdev, odp_port, false);
 143         return *tnl_portp != &void_tnl_port;
 144     } else if (tnl_port->ofport != ofport
 145                || tnl_port->netdev != netdev
 146                || tnl_port->match.odp_port != odp_port
 147                || tnl_port->netdev_seq != netdev_change_seq(netdev)) {
 148         VLOG_DBG("reconfiguring %s", tnl_port_get_name(tnl_port));
 149         tnl_port_del(tnl_port);
 150         *tnl_portp = tnl_port_add(ofport, netdev, odp_port);
 151         return true;
 152     }
 153     return false;
 154 }
 155
 156 /* Removes 'tnl_port' from the module. */
 157 void
 158 tnl_port_del(struct tnl_port *tnl_port)
 159 {
 160     if (tnl_port && tnl_port != &void_tnl_port) {
 161         tnl_port_mod_log(tnl_port, "removing");
 162         hmap_remove(&tnl_match_map, &tnl_port->match_node);
 163         netdev_close(tnl_port->netdev);
 164         free(tnl_port);
 165     }
 166 }
 167
 168 /* Looks in the table of tunnels for a tunnel matching the metadata in 'flow'.
 169  * Returns the 'ofport' corresponding to the new in_port, or a null pointer if
 170  * none is found.
 171  *
 172  * Callers should verify that 'flow' needs to be received by calling
 173  * tnl_port_should_receive() before this function. */
 174 const struct ofport_dpif *
 175 tnl_port_receive(const struct flow *flow)
 176 {
 177     char *pre_flow_str = NULL;
 178     struct tnl_port *tnl_port;
 179     struct tnl_match match;
 180
 181     memset(&match, 0, sizeof match);
 182     match.odp_port = flow->in_port.odp_port;
 183     match.ip_src = flow->tunnel.ip_dst;
 184     match.ip_dst = flow->tunnel.ip_src;
 185     match.in_key = flow->tunnel.tun_id;
 186     match.skb_mark = flow->skb_mark;
 187
 188     tnl_port = tnl_find(&match);
 189     if (!tnl_port) {
 190         struct ds ds = DS_EMPTY_INITIALIZER;
 191
 192         tnl_match_fmt(&match, &ds);
 193         VLOG_WARN_RL(&rl, "receive tunnel port not found (%s)", ds_cstr(&ds));
 194         ds_destroy(&ds);
 195         return NULL;
 196     }
 197
 198     if (!VLOG_DROP_DBG(&dbg_rl)) {
 199         pre_flow_str = flow_to_string(flow);
 200     }
 201
 202     if (pre_flow_str) {
 203         char *post_flow_str = flow_to_string(flow);
 204         char *tnl_str = tnl_port_fmt(tnl_port);
 205         VLOG_DBG("flow received\n"
 206                  "%s"
 207                  " pre: %s\n"
 208                  "post: %s",
 209                  tnl_str, pre_flow_str, post_flow_str);
 210         free(tnl_str);
 211         free(pre_flow_str);
 212         free(post_flow_str);
 213     }
 214     return tnl_port->ofport;
 215 }
 216
 217 /* Given that 'flow' should be output to the ofport corresponding to
 218  * 'tnl_port', updates 'flow''s tunnel headers and returns the actual datapath
 219  * port that the output should happen on.  May return ODPP_NONE if the output
 220  * shouldn't occur. */
 221 odp_port_t
 222 tnl_port_send(const struct tnl_port *tnl_port, struct flow *flow,
 223               struct flow_wildcards *wc)
 224 {
 225     const struct netdev_tunnel_config *cfg;
 226     char *pre_flow_str = NULL;
 227
 228     if (tnl_port == &void_tnl_port) {
 229         return ODPP_NONE;
 230     }
 231
 232     cfg = netdev_get_tunnel_config(tnl_port->netdev);
 233     ovs_assert(cfg);
 234
 235     if (!VLOG_DROP_DBG(&dbg_rl)) {
 236         pre_flow_str = flow_to_string(flow);
 237     }
 238
 239     if (!cfg->ip_src_flow) {
 240         flow->tunnel.ip_src = tnl_port->match.ip_src;
 241     }
 242     if (!cfg->ip_dst_flow) {
 243         flow->tunnel.ip_dst = tnl_port->match.ip_dst;
 244     }
 245     flow->skb_mark = tnl_port->match.skb_mark;
 246
 247     if (!cfg->out_key_flow) {
 248         flow->tunnel.tun_id = cfg->out_key;
 249     }
 250
 251     if (cfg->ttl_inherit && is_ip_any(flow)) {
 252         wc->masks.nw_ttl = 0xff;
 253         flow->tunnel.ip_ttl = flow->nw_ttl;
 254     } else {
 255         flow->tunnel.ip_ttl = cfg->ttl;
 256     }
 257
 258     if (cfg->tos_inherit && is_ip_any(flow)) {
 259         wc->masks.nw_tos = 0xff;
 260         flow->tunnel.ip_tos = flow->nw_tos & IP_DSCP_MASK;
 261     } else {
 262         flow->tunnel.ip_tos = cfg->tos;
 263     }
 264
 265     /* ECN fields are always inherited. */
 266     if (is_ip_any(flow)) {
 267         wc->masks.nw_tos |= IP_ECN_MASK;
 268     }
 269
 270     if ((flow->nw_tos & IP_ECN_MASK) == IP_ECN_CE) {
 271         flow->tunnel.ip_tos |= IP_ECN_ECT_0;
 272     } else {
 273         flow->tunnel.ip_tos |= flow->nw_tos & IP_ECN_MASK;
 274     }
 275
 276     flow->tunnel.flags = (cfg->dont_fragment ? FLOW_TNL_F_DONT_FRAGMENT : 0)
 277         | (cfg->csum ? FLOW_TNL_F_CSUM : 0)
 278         | (cfg->out_key_present ? FLOW_TNL_F_KEY : 0);
 279
 280     if (pre_flow_str) {
 281         char *post_flow_str = flow_to_string(flow);
 282         char *tnl_str = tnl_port_fmt(tnl_port);
 283         VLOG_DBG("flow sent\n"
 284                  "%s"
 285                  " pre: %s\n"
 286                  "post: %s",
 287                  tnl_str, pre_flow_str, post_flow_str);
 288         free(tnl_str);
 289         free(pre_flow_str);
 290         free(post_flow_str);
 291     }
 292
 293     return tnl_port->match.odp_port;
 294 }
 295
 296 static uint32_t
 297 tnl_hash(struct tnl_match *match)
 298 {
 299     BUILD_ASSERT_DECL(sizeof *match % sizeof(uint32_t) == 0);
 300     return hash_words((uint32_t *) match, sizeof *match / sizeof(uint32_t), 0);
 301 }
 302
 303 static struct tnl_port *
 304 tnl_find_exact(struct tnl_match *match)
 305 {
 306     struct tnl_port *tnl_port;
 307
 308     HMAP_FOR_EACH_WITH_HASH (tnl_port, match_node, tnl_hash(match),
 309                              &tnl_match_map) {
 310         if (!memcmp(match, &tnl_port->match, sizeof *match)) {
 311             return tnl_port;
 312         }
 313     }
 314     return NULL;
 315 }
 316
 317 static struct tnl_port *
 318 tnl_find(struct tnl_match *match_)
 319 {
 320     struct tnl_match match = *match_;
 321     struct tnl_port *tnl_port;
 322
 323     /* remote_ip, local_ip, in_key */
 324     tnl_port = tnl_find_exact(&match);
 325     if (tnl_port) {
 326         return tnl_port;
 327     }
 328
 329     /* remote_ip, in_key */
 330     match.ip_src = 0;
 331     tnl_port = tnl_find_exact(&match);
 332     if (tnl_port) {
 333         return tnl_port;
 334     }
 335     match.ip_src = match_->ip_src;
 336
 337     /* remote_ip, local_ip */
 338     match.in_key = 0;
 339     match.in_key_flow = true;
 340     tnl_port = tnl_find_exact(&match);
 341     if (tnl_port) {
 342         return tnl_port;
 343     }
 344
 345     /* remote_ip */
 346     match.ip_src = 0;
 347     tnl_port = tnl_find_exact(&match);
 348     if (tnl_port) {
 349         return tnl_port;
 350     }
 351
 352     /* Flow-based remote */
 353     match.ip_dst = 0;
 354     match.ip_dst_flow = true;
 355     tnl_port = tnl_find_exact(&match);
 356     if (tnl_port) {
 357         return tnl_port;
 358     }
 359
 360     /* Flow-based everything */
 361     match.ip_src = 0;
 362     match.ip_src_flow = true;
 363     tnl_port = tnl_find_exact(&match);
 364     if (tnl_port) {
 365         return tnl_port;
 366     }
 367
 368     return NULL;
 369 }
 370
 371 static void
 372 tnl_match_fmt(const struct tnl_match *match, struct ds *ds)
 373 {
 374     if (!match->ip_dst_flow) {
 375         ds_put_format(ds, IP_FMT"->"IP_FMT, IP_ARGS(match->ip_src),
 376                       IP_ARGS(match->ip_dst));
 377     } else if (!match->ip_src_flow) {
 378         ds_put_format(ds, IP_FMT"->flow", IP_ARGS(match->ip_src));
 379     } else {
 380         ds_put_cstr(ds, "flow->flow");
 381     }
 382
 383     if (match->in_key_flow) {
 384         ds_put_cstr(ds, ", key=flow");
 385     } else {
 386         ds_put_format(ds, ", key=%#"PRIx64, ntohll(match->in_key));
 387     }
 388
 389     ds_put_format(ds, ", dp port=%"PRIu32, match->odp_port);
 390     ds_put_format(ds, ", skb mark=%"PRIu32, match->skb_mark);
 391 }
 392
 393 static void
 394 tnl_port_mod_log(const struct tnl_port *tnl_port, const char *action)
 395 {
 396     if (VLOG_IS_DBG_ENABLED()) {
 397         struct ds ds = DS_EMPTY_INITIALIZER;
 398
 399         tnl_match_fmt(&tnl_port->match, &ds);
 400         VLOG_INFO("%s tunnel port %s (%s)", action,
 401                   tnl_port_get_name(tnl_port), ds_cstr(&ds));
 402         ds_destroy(&ds);
 403     }
 404 }
 405
 406 static char *
 407 tnl_port_fmt(const struct tnl_port *tnl_port)
 408 {
 409     const struct netdev_tunnel_config *cfg =
 410         netdev_get_tunnel_config(tnl_port->netdev);
 411     struct ds ds = DS_EMPTY_INITIALIZER;
 412
 413     ds_put_format(&ds, "port %"PRIu32": %s (%s: ", tnl_port->match.odp_port,
 414                   tnl_port_get_name(tnl_port),
 415                   netdev_get_type(tnl_port->netdev));
 416     tnl_match_fmt(&tnl_port->match, &ds);
 417
 418     if (cfg->out_key != cfg->in_key ||
 419         cfg->out_key_present != cfg->in_key_present ||
 420         cfg->out_key_flow != cfg->in_key_flow) {
 421         ds_put_cstr(&ds, ", out_key=");
 422         if (!cfg->out_key_present) {
 423             ds_put_cstr(&ds, "none");
 424         } else if (cfg->out_key_flow) {
 425             ds_put_cstr(&ds, "flow");
 426         } else {
 427             ds_put_format(&ds, "%#"PRIx64, ntohll(cfg->out_key));
 428         }
 429     }
 430
 431     if (cfg->ttl_inherit) {
 432         ds_put_cstr(&ds, ", ttl=inherit");
 433     } else {
 434         ds_put_format(&ds, ", ttl=%"PRIu8, cfg->ttl);
 435     }
 436
 437     if (cfg->tos_inherit) {
 438         ds_put_cstr(&ds, ", tos=inherit");
 439     } else if (cfg->tos) {
 440         ds_put_format(&ds, ", tos=%#"PRIx8, cfg->tos);
 441     }
 442
 443     if (!cfg->dont_fragment) {
 444         ds_put_cstr(&ds, ", df=false");
 445     }
 446
 447     if (cfg->csum) {
 448         ds_put_cstr(&ds, ", csum=true");
 449     }
 450
 451     ds_put_cstr(&ds, ")\n");
 452
 453     return ds_steal_cstr(&ds);
 454 }
 455
 456 static const char *
 457 tnl_port_get_name(const struct tnl_port *tnl_port)
 458 {
 459     return netdev_get_name(tnl_port->netdev);
 460 }