lib/bundle.c

   1 /* Copyright (c) 2011, 2012, 2013, 2014, 2015, 2016, 2017 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
  16 #include <config.h>
  17
  18 #include "bundle.h"
  19
  20 #include <sys/types.h>
  21 #include <netinet/in.h>
  22 #include <arpa/inet.h>
  23 #include <inttypes.h>
  24
  25 #include "colors.h"
  26 #include "multipath.h"
  27 #include "nx-match.h"
  28 #include "openflow/nicira-ext.h"
  29 #include "openvswitch/dynamic-string.h"
  30 #include "openvswitch/meta-flow.h"
  31 #include "openvswitch/ofp-actions.h"
  32 #include "openvswitch/ofp-errors.h"
  33 #include "openvswitch/ofp-port.h"
  34 #include "openvswitch/ofpbuf.h"
  35 #include "openvswitch/vlog.h"
  36 #include "util.h"
  37
  38 VLOG_DEFINE_THIS_MODULE(bundle);
  39
  40 static ofp_port_t
  41 execute_ab(const struct ofpact_bundle *bundle,
  42            bool (*slave_enabled)(ofp_port_t ofp_port, void *aux), void *aux)
  43 {
  44     size_t i;
  45
  46     for (i = 0; i < bundle->n_slaves; i++) {
  47         ofp_port_t slave = bundle->slaves[i];
  48         if (slave_enabled(slave, aux)) {
  49             return slave;
  50         }
  51     }
  52
  53     return OFPP_NONE;
  54 }
  55
  56 static ofp_port_t
  57 execute_hrw(const struct ofpact_bundle *bundle,
  58             const struct flow *flow, struct flow_wildcards *wc,
  59             bool (*slave_enabled)(ofp_port_t ofp_port, void *aux), void *aux)
  60 {
  61     uint32_t flow_hash, best_hash;
  62     int best, i;
  63
  64     if (bundle->n_slaves > 1) {
  65         flow_mask_hash_fields(flow, wc, bundle->fields);
  66     }
  67
  68     flow_hash = flow_hash_fields(flow, bundle->fields, bundle->basis);
  69     best = -1;
  70     best_hash = 0;
  71
  72     for (i = 0; i < bundle->n_slaves; i++) {
  73         if (slave_enabled(bundle->slaves[i], aux)) {
  74             uint32_t hash = hash_2words(i, flow_hash);
  75
  76             if (best < 0 || hash > best_hash) {
  77                 best_hash = hash;
  78                 best = i;
  79             }
  80         }
  81     }
  82
  83     return best >= 0 ? bundle->slaves[best] : OFPP_NONE;
  84 }
  85
  86 /* Executes 'bundle' on 'flow'.  Sets fields in 'wc' that were used to
  87  * calculate the result.  Uses 'slave_enabled' to determine if the slave
  88  * designated by 'ofp_port' is up.  Returns the chosen slave, or
  89  * OFPP_NONE if none of the slaves are acceptable. */
  90 ofp_port_t
  91 bundle_execute(const struct ofpact_bundle *bundle,
  92                const struct flow *flow, struct flow_wildcards *wc,
  93                bool (*slave_enabled)(ofp_port_t ofp_port, void *aux),
  94                void *aux)
  95 {
  96     switch (bundle->algorithm) {
  97     case NX_BD_ALG_HRW:
  98         return execute_hrw(bundle, flow, wc, slave_enabled, aux);
  99
 100     case NX_BD_ALG_ACTIVE_BACKUP:
 101         return execute_ab(bundle, slave_enabled, aux);
 102
 103     default:
 104         OVS_NOT_REACHED();
 105     }
 106 }
 107
 108 enum ofperr
 109 bundle_check(const struct ofpact_bundle *bundle, ofp_port_t max_ports,
 110              const struct match *match)
 111 {
 112     static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5);
 113     size_t i;
 114
 115     if (bundle->dst.field) {
 116         enum ofperr error = mf_check_dst(&bundle->dst, match);
 117         if (error) {
 118             return error;
 119         }
 120     }
 121
 122     for (i = 0; i < bundle->n_slaves; i++) {
 123         ofp_port_t ofp_port = bundle->slaves[i];
 124
 125         if (ofp_port != OFPP_NONE) {
 126             enum ofperr error = ofpact_check_output_port(ofp_port, max_ports);
 127             if (error) {
 128                 VLOG_WARN_RL(&rl, "invalid slave %"PRIu32, ofp_port);
 129                 return error;
 130             }
 131         }
 132         /* Controller slaves are unsupported due to the lack of a max_len
 133          * argument. This may or may not change in the future.  There doesn't
 134          * seem to be a real-world use-case for supporting it. */
 135         if (ofp_port == OFPP_CONTROLLER) {
 136             VLOG_WARN_RL(&rl, "unsupported controller slave");
 137             return OFPERR_OFPBAC_BAD_OUT_PORT;
 138         }
 139     }
 140
 141     return 0;
 142 }
 143
 144
 145 /* Helper for bundle_parse and bundle_parse_load.
 146  *
 147  * Returns NULL if successful, otherwise a malloc()'d string describing the
 148  * error.  The caller is responsible for freeing the returned string.*/
 149 static char * OVS_WARN_UNUSED_RESULT
 150 bundle_parse__(const char *s, const struct ofputil_port_map *port_map,
 151                char **save_ptr,
 152                const char *fields, const char *basis, const char *algorithm,
 153                const char *slave_type, const char *dst,
 154                const char *slave_delim, struct ofpbuf *ofpacts)
 155 {
 156     struct ofpact_bundle *bundle;
 157
 158     if (!slave_delim) {
 159         return xasprintf("%s: not enough arguments to bundle action", s);
 160     }
 161
 162     if (strcasecmp(slave_delim, "slaves")) {
 163         return xasprintf("%s: missing slave delimiter, expected `slaves' "
 164                          "got `%s'", s, slave_delim);
 165     }
 166
 167     bundle = ofpact_put_BUNDLE(ofpacts);
 168
 169     for (;;) {
 170         ofp_port_t slave_port;
 171         char *slave;
 172
 173         slave = strtok_r(NULL, ", []", save_ptr);
 174         if (!slave || bundle->n_slaves >= BUNDLE_MAX_SLAVES) {
 175             break;
 176         }
 177
 178         if (!ofputil_port_from_string(slave, port_map, &slave_port)) {
 179             return xasprintf("%s: bad port number", slave);
 180         }
 181         ofpbuf_put(ofpacts, &slave_port, sizeof slave_port);
 182
 183         bundle = ofpacts->header;
 184         bundle->n_slaves++;
 185     }
 186     ofpact_finish_BUNDLE(ofpacts, &bundle);
 187     bundle->basis = atoi(basis);
 188
 189     if (!strcasecmp(fields, "eth_src")) {
 190         bundle->fields = NX_HASH_FIELDS_ETH_SRC;
 191     } else if (!strcasecmp(fields, "symmetric_l4")) {
 192         bundle->fields = NX_HASH_FIELDS_SYMMETRIC_L4;
 193     } else if (!strcasecmp(fields, "symmetric_l3l4")) {
 194         bundle->fields = NX_HASH_FIELDS_SYMMETRIC_L3L4;
 195     } else if (!strcasecmp(fields, "symmetric_l3l4+udp")) {
 196         bundle->fields = NX_HASH_FIELDS_SYMMETRIC_L3L4_UDP;
 197     } else if (!strcasecmp(fields, "nw_src")) {
 198         bundle->fields = NX_HASH_FIELDS_NW_SRC;
 199     } else if (!strcasecmp(fields, "nw_dst")) {
 200         bundle->fields = NX_HASH_FIELDS_NW_DST;
 201     } else {
 202         return xasprintf("%s: unknown fields `%s'", s, fields);
 203     }
 204
 205     if (!strcasecmp(algorithm, "active_backup")) {
 206         bundle->algorithm = NX_BD_ALG_ACTIVE_BACKUP;
 207     } else if (!strcasecmp(algorithm, "hrw")) {
 208         bundle->algorithm = NX_BD_ALG_HRW;
 209     } else {
 210         return xasprintf("%s: unknown algorithm `%s'", s, algorithm);
 211     }
 212
 213     if (strcasecmp(slave_type, "ofport")) {
 214         return xasprintf("%s: unknown slave_type `%s'", s, slave_type);
 215     }
 216
 217     if (dst) {
 218         char *error = mf_parse_subfield(&bundle->dst, dst);
 219         if (error) {
 220             return error;
 221         }
 222
 223         if (!mf_nxm_header(bundle->dst.field->id)) {
 224             return xasprintf("%s: experimenter OXM field '%s' not supported",
 225                              s, dst);
 226         }
 227     }
 228
 229     return NULL;
 230 }
 231
 232 /* Converts a bundle action string contained in 's' to an nx_action_bundle and
 233  * stores it in 'b'.  Sets 'b''s l2 pointer to NULL.
 234  *
 235  * Returns NULL if successful, otherwise a malloc()'d string describing the
 236  * error.  The caller is responsible for freeing the returned string. */
 237 char * OVS_WARN_UNUSED_RESULT
 238 bundle_parse(const char *s, const struct ofputil_port_map *port_map,
 239              struct ofpbuf *ofpacts)
 240 {
 241     char *fields, *basis, *algorithm, *slave_type, *slave_delim;
 242     char *tokstr, *save_ptr;
 243     char *error;
 244
 245     save_ptr = NULL;
 246     tokstr = xstrdup(s);
 247     fields = strtok_r(tokstr, ", ", &save_ptr);
 248     basis = strtok_r(NULL, ", ", &save_ptr);
 249     algorithm = strtok_r(NULL, ", ", &save_ptr);
 250     slave_type = strtok_r(NULL, ", ", &save_ptr);
 251     slave_delim = strtok_r(NULL, ": ", &save_ptr);
 252
 253     error = bundle_parse__(s, port_map,
 254                            &save_ptr, fields, basis, algorithm, slave_type,
 255                            NULL, slave_delim, ofpacts);
 256     free(tokstr);
 257
 258     return error;
 259 }
 260
 261 /* Converts a bundle_load action string contained in 's' to an nx_action_bundle
 262  * and stores it in 'b'.  Sets 'b''s l2 pointer to NULL.
 263  *
 264  * Returns NULL if successful, otherwise a malloc()'d string describing the
 265  * error.  The caller is responsible for freeing the returned string.*/
 266 char * OVS_WARN_UNUSED_RESULT
 267 bundle_parse_load(const char *s, const struct ofputil_port_map *port_map,
 268                   struct ofpbuf *ofpacts)
 269 {
 270     char *fields, *basis, *algorithm, *slave_type, *dst, *slave_delim;
 271     char *tokstr, *save_ptr;
 272     char *error;
 273
 274     save_ptr = NULL;
 275     tokstr = xstrdup(s);
 276     fields = strtok_r(tokstr, ", ", &save_ptr);
 277     basis = strtok_r(NULL, ", ", &save_ptr);
 278     algorithm = strtok_r(NULL, ", ", &save_ptr);
 279     slave_type = strtok_r(NULL, ", ", &save_ptr);
 280     dst = strtok_r(NULL, ", ", &save_ptr);
 281     slave_delim = strtok_r(NULL, ": ", &save_ptr);
 282
 283     error = bundle_parse__(s, port_map,
 284                            &save_ptr, fields, basis, algorithm, slave_type,
 285                            dst, slave_delim, ofpacts);
 286
 287     free(tokstr);
 288
 289     return error;
 290 }
 291
 292 /* Appends a human-readable representation of 'nab' to 's'.  If 'port_map' is
 293  * nonnull, uses it to translate port numbers to names in output. */
 294 void
 295 bundle_format(const struct ofpact_bundle *bundle,
 296               const struct ofputil_port_map *port_map, struct ds *s)
 297 {
 298     const char *action, *fields, *algorithm;
 299     size_t i;
 300
 301     fields = flow_hash_fields_to_str(bundle->fields);
 302
 303     switch (bundle->algorithm) {
 304     case NX_BD_ALG_HRW:
 305         algorithm = "hrw";
 306         break;
 307     case NX_BD_ALG_ACTIVE_BACKUP:
 308         algorithm = "active_backup";
 309         break;
 310     default:
 311         algorithm = "<unknown>";
 312     }
 313
 314     action = bundle->dst.field ? "bundle_load" : "bundle";
 315
 316     ds_put_format(s, "%s%s(%s%s,%"PRIu16",%s,%s,", colors.paren, action,
 317                   colors.end, fields, bundle->basis, algorithm, "ofport");
 318
 319     if (bundle->dst.field) {
 320         mf_format_subfield(&bundle->dst, s);
 321         ds_put_char(s, ',');
 322     }
 323
 324     ds_put_format(s, "%sslaves:%s", colors.param, colors.end);
 325     for (i = 0; i < bundle->n_slaves; i++) {
 326         if (i) {
 327             ds_put_char(s, ',');
 328         }
 329
 330         ofputil_format_port(bundle->slaves[i], port_map, s);
 331     }
 332
 333     ds_put_format(s, "%s)%s", colors.paren, colors.end);
 334 }