lib/ofp-parse.c

   1 /*
   2  * Copyright (c) 2010 Nicira Networks.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at:
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 #include <config.h>
  18
  19 #include "ofp-parse.h"
  20
  21 #include <errno.h>
  22 #include <stdlib.h>
  23
  24 #include "byte-order.h"
  25 #include "dynamic-string.h"
  26 #include "netdev.h"
  27 #include "ofp-util.h"
  28 #include "ofpbuf.h"
  29 #include "openflow/openflow.h"
  30 #include "packets.h"
  31 #include "socket-util.h"
  32 #include "vconn.h"
  33 #include "vlog.h"
  34
  35 VLOG_DEFINE_THIS_MODULE(ofp_parse)
  36
  37 static uint32_t
  38 str_to_u32(const char *str)
  39 {
  40     char *tail;
  41     uint32_t value;
  42
  43     if (!str) {
  44         ovs_fatal(0, "missing required numeric argument");
  45     }
  46
  47     errno = 0;
  48     value = strtoul(str, &tail, 0);
  49     if (errno == EINVAL || errno == ERANGE || *tail) {
  50         ovs_fatal(0, "invalid numeric format %s", str);
  51     }
  52     return value;
  53 }
  54
  55 static uint64_t
  56 str_to_u64(const char *str)
  57 {
  58     char *tail;
  59     uint64_t value;
  60
  61     errno = 0;
  62     value = strtoull(str, &tail, 0);
  63     if (errno == EINVAL || errno == ERANGE || *tail) {
  64         ovs_fatal(0, "invalid numeric format %s", str);
  65     }
  66     return value;
  67 }
  68
  69 static void
  70 str_to_mac(const char *str, uint8_t mac[6])
  71 {
  72     if (sscanf(str, ETH_ADDR_SCAN_FMT, ETH_ADDR_SCAN_ARGS(mac))
  73         != ETH_ADDR_SCAN_COUNT) {
  74         ovs_fatal(0, "invalid mac address %s", str);
  75     }
  76 }
  77
  78 static uint32_t
  79 str_to_ip(const char *str_, uint32_t *ip)
  80 {
  81     char *str = xstrdup(str_);
  82     char *save_ptr = NULL;
  83     const char *name, *netmask;
  84     struct in_addr in_addr;
  85     int n_wild, retval;
  86
  87     name = strtok_r(str, "/", &save_ptr);
  88     retval = name ? lookup_ip(name, &in_addr) : EINVAL;
  89     if (retval) {
  90         ovs_fatal(0, "%s: could not convert to IP address", str);
  91     }
  92     *ip = in_addr.s_addr;
  93
  94     netmask = strtok_r(NULL, "/", &save_ptr);
  95     if (netmask) {
  96         uint8_t o[4];
  97         if (sscanf(netmask, "%"SCNu8".%"SCNu8".%"SCNu8".%"SCNu8,
  98                    &o[0], &o[1], &o[2], &o[3]) == 4) {
  99             uint32_t nm = (o[0] << 24) | (o[1] << 16) | (o[2] << 8) | o[3];
 100             int i;
 101
 102             /* Find first 1-bit. */
 103             for (i = 0; i < 32; i++) {
 104                 if (nm & (1u << i)) {
 105                     break;
 106                 }
 107             }
 108             n_wild = i;
 109
 110             /* Verify that the rest of the bits are 1-bits. */
 111             for (; i < 32; i++) {
 112                 if (!(nm & (1u << i))) {
 113                     ovs_fatal(0, "%s: %s is not a valid netmask",
 114                               str, netmask);
 115                 }
 116             }
 117         } else {
 118             int prefix = atoi(netmask);
 119             if (prefix <= 0 || prefix > 32) {
 120                 ovs_fatal(0, "%s: network prefix bits not between 1 and 32",
 121                           str);
 122             }
 123             n_wild = 32 - prefix;
 124         }
 125     } else {
 126         n_wild = 0;
 127     }
 128
 129     free(str);
 130     return n_wild;
 131 }
 132
 133 static void *
 134 put_action(struct ofpbuf *b, size_t size, uint16_t type)
 135 {
 136     struct ofp_action_header *ah = ofpbuf_put_zeros(b, size);
 137     ah->type = htons(type);
 138     ah->len = htons(size);
 139     return ah;
 140 }
 141
 142 static struct ofp_action_output *
 143 put_output_action(struct ofpbuf *b, uint16_t port)
 144 {
 145     struct ofp_action_output *oao = put_action(b, sizeof *oao, OFPAT_OUTPUT);
 146     oao->port = htons(port);
 147     return oao;
 148 }
 149
 150 static void
 151 put_enqueue_action(struct ofpbuf *b, uint16_t port, uint32_t queue)
 152 {
 153     struct ofp_action_enqueue *oae = put_action(b, sizeof *oae, OFPAT_ENQUEUE);
 154     oae->port = htons(port);
 155     oae->queue_id = htonl(queue);
 156 }
 157
 158 static void
 159 put_dl_addr_action(struct ofpbuf *b, uint16_t type, const char *addr)
 160 {
 161     struct ofp_action_dl_addr *oada = put_action(b, sizeof *oada, type);
 162     str_to_mac(addr, oada->dl_addr);
 163 }
 164
 165
 166 static bool
 167 parse_port_name(const char *name, uint16_t *port)
 168 {
 169     struct pair {
 170         const char *name;
 171         uint16_t value;
 172     };
 173     static const struct pair pairs[] = {
 174 #define DEF_PAIR(NAME) {#NAME, OFPP_##NAME}
 175         DEF_PAIR(IN_PORT),
 176         DEF_PAIR(TABLE),
 177         DEF_PAIR(NORMAL),
 178         DEF_PAIR(FLOOD),
 179         DEF_PAIR(ALL),
 180         DEF_PAIR(CONTROLLER),
 181         DEF_PAIR(LOCAL),
 182         DEF_PAIR(NONE),
 183 #undef DEF_PAIR
 184     };
 185     static const int n_pairs = ARRAY_SIZE(pairs);
 186     size_t i;
 187
 188     for (i = 0; i < n_pairs; i++) {
 189         if (!strcasecmp(name, pairs[i].name)) {
 190             *port = pairs[i].value;
 191             return true;
 192         }
 193     }
 194     return false;
 195 }
 196
 197 static void
 198 str_to_action(char *str, struct ofpbuf *b)
 199 {
 200     char *act, *arg;
 201     char *saveptr = NULL;
 202     bool drop = false;
 203     int n_actions;
 204
 205     for (act = strtok_r(str, ", \t\r\n", &saveptr), n_actions = 0; act;
 206          act = strtok_r(NULL, ", \t\r\n", &saveptr), n_actions++)
 207     {
 208         uint16_t port;
 209
 210         if (drop) {
 211             ovs_fatal(0, "Drop actions must not be followed by other actions");
 212         }
 213
 214         /* Arguments are separated by colons */
 215         arg = strchr(act, ':');
 216         if (arg) {
 217             *arg = '\0';
 218             arg++;
 219         }
 220
 221         if (!strcasecmp(act, "mod_vlan_vid")) {
 222             struct ofp_action_vlan_vid *va;
 223             va = put_action(b, sizeof *va, OFPAT_SET_VLAN_VID);
 224             va->vlan_vid = htons(str_to_u32(arg));
 225         } else if (!strcasecmp(act, "mod_vlan_pcp")) {
 226             struct ofp_action_vlan_pcp *va;
 227             va = put_action(b, sizeof *va, OFPAT_SET_VLAN_PCP);
 228             va->vlan_pcp = str_to_u32(arg);
 229         } else if (!strcasecmp(act, "strip_vlan")) {
 230             struct ofp_action_header *ah;
 231             ah = put_action(b, sizeof *ah, OFPAT_STRIP_VLAN);
 232             ah->type = htons(OFPAT_STRIP_VLAN);
 233         } else if (!strcasecmp(act, "mod_dl_src")) {
 234             put_dl_addr_action(b, OFPAT_SET_DL_SRC, arg);
 235         } else if (!strcasecmp(act, "mod_dl_dst")) {
 236             put_dl_addr_action(b, OFPAT_SET_DL_DST, arg);
 237         } else if (!strcasecmp(act, "mod_nw_src")) {
 238             struct ofp_action_nw_addr *na;
 239             na = put_action(b, sizeof *na, OFPAT_SET_NW_SRC);
 240             str_to_ip(arg, &na->nw_addr);
 241         } else if (!strcasecmp(act, "mod_nw_dst")) {
 242             struct ofp_action_nw_addr *na;
 243             na = put_action(b, sizeof *na, OFPAT_SET_NW_DST);
 244             str_to_ip(arg, &na->nw_addr);
 245         } else if (!strcasecmp(act, "mod_tp_src")) {
 246             struct ofp_action_tp_port *ta;
 247             ta = put_action(b, sizeof *ta, OFPAT_SET_TP_SRC);
 248             ta->tp_port = htons(str_to_u32(arg));
 249         } else if (!strcasecmp(act, "mod_tp_dst")) {
 250             struct ofp_action_tp_port *ta;
 251             ta = put_action(b, sizeof *ta, OFPAT_SET_TP_DST);
 252             ta->tp_port = htons(str_to_u32(arg));
 253         } else if (!strcasecmp(act, "mod_nw_tos")) {
 254             struct ofp_action_nw_tos *nt;
 255             nt = put_action(b, sizeof *nt, OFPAT_SET_NW_TOS);
 256             nt->nw_tos = str_to_u32(arg);
 257         } else if (!strcasecmp(act, "resubmit")) {
 258             struct nx_action_resubmit *nar;
 259             nar = put_action(b, sizeof *nar, OFPAT_VENDOR);
 260             nar->vendor = htonl(NX_VENDOR_ID);
 261             nar->subtype = htons(NXAST_RESUBMIT);
 262             nar->in_port = htons(str_to_u32(arg));
 263         } else if (!strcasecmp(act, "set_tunnel")) {
 264             struct nx_action_set_tunnel *nast;
 265             nast = put_action(b, sizeof *nast, OFPAT_VENDOR);
 266             nast->vendor = htonl(NX_VENDOR_ID);
 267             nast->subtype = htons(NXAST_SET_TUNNEL);
 268             nast->tun_id = htonl(str_to_u32(arg));
 269         } else if (!strcasecmp(act, "drop_spoofed_arp")) {
 270             struct nx_action_header *nah;
 271             nah = put_action(b, sizeof *nah, OFPAT_VENDOR);
 272             nah->vendor = htonl(NX_VENDOR_ID);
 273             nah->subtype = htons(NXAST_DROP_SPOOFED_ARP);
 274         } else if (!strcasecmp(act, "set_queue")) {
 275             struct nx_action_set_queue *nasq;
 276             nasq = put_action(b, sizeof *nasq, OFPAT_VENDOR);
 277             nasq->vendor = htonl(NX_VENDOR_ID);
 278             nasq->subtype = htons(NXAST_SET_QUEUE);
 279             nasq->queue_id = htonl(str_to_u32(arg));
 280         } else if (!strcasecmp(act, "pop_queue")) {
 281             struct nx_action_header *nah;
 282             nah = put_action(b, sizeof *nah, OFPAT_VENDOR);
 283             nah->vendor = htonl(NX_VENDOR_ID);
 284             nah->subtype = htons(NXAST_POP_QUEUE);
 285         } else if (!strcasecmp(act, "output")) {
 286             put_output_action(b, str_to_u32(arg));
 287         } else if (!strcasecmp(act, "enqueue")) {
 288             char *sp = NULL;
 289             char *port_s = strtok_r(arg, ":q", &sp);
 290             char *queue = strtok_r(NULL, "", &sp);
 291             if (port_s == NULL || queue == NULL) {
 292                 ovs_fatal(0, "\"enqueue\" syntax is \"enqueue:PORT:QUEUE\"");
 293             }
 294             put_enqueue_action(b, str_to_u32(port_s), str_to_u32(queue));
 295         } else if (!strcasecmp(act, "drop")) {
 296             /* A drop action in OpenFlow occurs by just not setting
 297              * an action. */
 298             drop = true;
 299             if (n_actions) {
 300                 ovs_fatal(0, "Drop actions must not be preceded by other "
 301                           "actions");
 302             }
 303         } else if (!strcasecmp(act, "CONTROLLER")) {
 304             struct ofp_action_output *oao;
 305             oao = put_output_action(b, OFPP_CONTROLLER);
 306
 307             /* Unless a numeric argument is specified, we send the whole
 308              * packet to the controller. */
 309             if (arg && (strspn(arg, "0123456789") == strlen(arg))) {
 310                oao->max_len = htons(str_to_u32(arg));
 311             } else {
 312                 oao->max_len = htons(UINT16_MAX);
 313             }
 314         } else if (parse_port_name(act, &port)) {
 315             put_output_action(b, port);
 316         } else if (strspn(act, "0123456789") == strlen(act)) {
 317             put_output_action(b, str_to_u32(act));
 318         } else {
 319             ovs_fatal(0, "Unknown action: %s", act);
 320         }
 321     }
 322 }
 323
 324 struct protocol {
 325     const char *name;
 326     uint16_t dl_type;
 327     uint8_t nw_proto;
 328 };
 329
 330 static bool
 331 parse_protocol(const char *name, const struct protocol **p_out)
 332 {
 333     static const struct protocol protocols[] = {
 334         { "ip", ETH_TYPE_IP, 0 },
 335         { "arp", ETH_TYPE_ARP, 0 },
 336         { "icmp", ETH_TYPE_IP, IP_TYPE_ICMP },
 337         { "tcp", ETH_TYPE_IP, IP_TYPE_TCP },
 338         { "udp", ETH_TYPE_IP, IP_TYPE_UDP },
 339     };
 340     const struct protocol *p;
 341
 342     for (p = protocols; p < &protocols[ARRAY_SIZE(protocols)]; p++) {
 343         if (!strcmp(p->name, name)) {
 344             *p_out = p;
 345             return true;
 346         }
 347     }
 348     *p_out = NULL;
 349     return false;
 350 }
 351
 352 struct field {
 353     const char *name;
 354     uint32_t wildcard;
 355     enum { F_U8, F_U16, F_MAC, F_IP } type;
 356     size_t offset, shift;
 357 };
 358
 359 static bool
 360 parse_field(const char *name, const struct field **f_out)
 361 {
 362 #define F_OFS(MEMBER) offsetof(struct ofp_match, MEMBER)
 363     static const struct field fields[] = {
 364         { "in_port", OFPFW_IN_PORT, F_U16, F_OFS(in_port), 0 },
 365         { "dl_vlan", OFPFW_DL_VLAN, F_U16, F_OFS(dl_vlan), 0 },
 366         { "dl_vlan_pcp", OFPFW_DL_VLAN_PCP, F_U8, F_OFS(dl_vlan_pcp), 0 },
 367         { "dl_src", OFPFW_DL_SRC, F_MAC, F_OFS(dl_src), 0 },
 368         { "dl_dst", OFPFW_DL_DST, F_MAC, F_OFS(dl_dst), 0 },
 369         { "dl_type", OFPFW_DL_TYPE, F_U16, F_OFS(dl_type), 0 },
 370         { "nw_src", OFPFW_NW_SRC_MASK, F_IP,
 371           F_OFS(nw_src), OFPFW_NW_SRC_SHIFT },
 372         { "nw_dst", OFPFW_NW_DST_MASK, F_IP,
 373           F_OFS(nw_dst), OFPFW_NW_DST_SHIFT },
 374         { "nw_proto", OFPFW_NW_PROTO, F_U8, F_OFS(nw_proto), 0 },
 375         { "nw_tos", OFPFW_NW_TOS, F_U8, F_OFS(nw_tos), 0 },
 376         { "tp_src", OFPFW_TP_SRC, F_U16, F_OFS(tp_src), 0 },
 377         { "tp_dst", OFPFW_TP_DST, F_U16, F_OFS(tp_dst), 0 },
 378         { "icmp_type", OFPFW_ICMP_TYPE, F_U16, F_OFS(icmp_type), 0 },
 379         { "icmp_code", OFPFW_ICMP_CODE, F_U16, F_OFS(icmp_code), 0 }
 380     };
 381     const struct field *f;
 382
 383     for (f = fields; f < &fields[ARRAY_SIZE(fields)]; f++) {
 384         if (!strcmp(f->name, name)) {
 385             *f_out = f;
 386             return true;
 387         }
 388     }
 389     *f_out = NULL;
 390     return false;
 391 }
 392
 393 /* Convert 'string' (as described in the Flow Syntax section of the
 394  * ovs-ofctl man page) into 'match'.  The other arguments are optional
 395  * and may be NULL if their value is not needed.  If 'actions' is
 396  * specified, an action must be in 'string' and may be expanded or
 397  * reallocated. */
 398 void
 399 parse_ofp_str(char *string, struct ofp_match *match, struct ofpbuf *actions,
 400               uint8_t *table_idx, uint16_t *out_port, uint16_t *priority,
 401               uint16_t *idle_timeout, uint16_t *hard_timeout,
 402               uint64_t *cookie)
 403 {
 404     struct ofp_match normalized;
 405     char *save_ptr = NULL;
 406     char *name;
 407     uint32_t wildcards;
 408
 409     if (table_idx) {
 410         *table_idx = 0xff;
 411     }
 412     if (out_port) {
 413         *out_port = OFPP_NONE;
 414     }
 415     if (priority) {
 416         *priority = OFP_DEFAULT_PRIORITY;
 417     }
 418     if (idle_timeout) {
 419         *idle_timeout = OFP_FLOW_PERMANENT;
 420     }
 421     if (hard_timeout) {
 422         *hard_timeout = OFP_FLOW_PERMANENT;
 423     }
 424     if (cookie) {
 425         *cookie = 0;
 426     }
 427     if (actions) {
 428         char *act_str = strstr(string, "action");
 429         if (!act_str) {
 430             ovs_fatal(0, "must specify an action");
 431         }
 432         *act_str = '\0';
 433
 434         act_str = strchr(act_str + 1, '=');
 435         if (!act_str) {
 436             ovs_fatal(0, "must specify an action");
 437         }
 438
 439         act_str++;
 440
 441         str_to_action(act_str, actions);
 442     }
 443     memset(match, 0, sizeof *match);
 444     wildcards = OFPFW_ALL;
 445     for (name = strtok_r(string, "=, \t\r\n", &save_ptr); name;
 446          name = strtok_r(NULL, "=, \t\r\n", &save_ptr)) {
 447         const struct protocol *p;
 448
 449         if (parse_protocol(name, &p)) {
 450             wildcards &= ~OFPFW_DL_TYPE;
 451             match->dl_type = htons(p->dl_type);
 452             if (p->nw_proto) {
 453                 wildcards &= ~OFPFW_NW_PROTO;
 454                 match->nw_proto = p->nw_proto;
 455             }
 456         } else {
 457             const struct field *f;
 458             char *value;
 459
 460             value = strtok_r(NULL, ", \t\r\n", &save_ptr);
 461             if (!value) {
 462                 ovs_fatal(0, "field %s missing value", name);
 463             }
 464
 465             if (table_idx && !strcmp(name, "table")) {
 466                 *table_idx = atoi(value);
 467             } else if (out_port && !strcmp(name, "out_port")) {
 468                 *out_port = atoi(value);
 469             } else if (priority && !strcmp(name, "priority")) {
 470                 *priority = atoi(value);
 471             } else if (idle_timeout && !strcmp(name, "idle_timeout")) {
 472                 *idle_timeout = atoi(value);
 473             } else if (hard_timeout && !strcmp(name, "hard_timeout")) {
 474                 *hard_timeout = atoi(value);
 475             } else if (cookie && !strcmp(name, "cookie")) {
 476                 *cookie = str_to_u64(value);
 477             } else if (!strcmp(name, "tun_id_wild")) {
 478                 wildcards |= NXFW_TUN_ID;
 479             } else if (parse_field(name, &f)) {
 480                 void *data = (char *) match + f->offset;
 481                 if (!strcmp(value, "*") || !strcmp(value, "ANY")) {
 482                     wildcards |= f->wildcard;
 483                 } else {
 484                     uint16_t port_no;
 485
 486                     wildcards &= ~f->wildcard;
 487                     if (f->wildcard == OFPFW_IN_PORT
 488                         && parse_port_name(value, &port_no)) {
 489                         match->in_port = htons(port_no);
 490                     } else if (f->type == F_U8) {
 491                         *(uint8_t *) data = str_to_u32(value);
 492                     } else if (f->type == F_U16) {
 493                         *(uint16_t *) data = htons(str_to_u32(value));
 494                     } else if (f->type == F_MAC) {
 495                         str_to_mac(value, data);
 496                     } else if (f->type == F_IP) {
 497                         wildcards |= str_to_ip(value, data) << f->shift;
 498                     } else {
 499                         NOT_REACHED();
 500                     }
 501                 }
 502             } else {
 503                 ovs_fatal(0, "unknown keyword %s", name);
 504             }
 505         }
 506     }
 507     match->wildcards = htonl(wildcards);
 508
 509     normalized = *match;
 510     normalize_match(&normalized);
 511     if (memcmp(match, &normalized, sizeof normalized)) {
 512         char *old = ofp_match_to_literal_string(match);
 513         char *new = ofp_match_to_literal_string(&normalized);
 514         VLOG_WARN("The specified flow is not in normal form:");
 515         VLOG_WARN(" as specified: %s", old);
 516         VLOG_WARN("as normalized: %s", new);
 517         free(old);
 518         free(new);
 519     }
 520 }
 521
 522 /* Parses 'string' as a OFPT_FLOW_MOD with subtype OFPFC_ADD and returns an
 523  * ofpbuf that contains it. */
 524 struct ofpbuf *
 525 parse_ofp_add_flow_str(char *string)
 526 {
 527     struct ofpbuf *buffer;
 528     struct ofp_flow_mod *ofm;
 529     uint16_t priority, idle_timeout, hard_timeout;
 530     uint64_t cookie;
 531     struct ofp_match match;
 532
 533     /* parse_ofp_str() will expand and reallocate the data in 'buffer', so we
 534      * can't keep pointers to across the parse_ofp_str() call. */
 535     make_openflow(sizeof *ofm, OFPT_FLOW_MOD, &buffer);
 536     parse_ofp_str(string, &match, buffer,
 537                   NULL, NULL, &priority, &idle_timeout, &hard_timeout,
 538                   &cookie);
 539     ofm = buffer->data;
 540     ofm->match = match;
 541     ofm->command = htons(OFPFC_ADD);
 542     ofm->cookie = htonll(cookie);
 543     ofm->idle_timeout = htons(idle_timeout);
 544     ofm->hard_timeout = htons(hard_timeout);
 545     ofm->buffer_id = htonl(UINT32_MAX);
 546     ofm->priority = htons(priority);
 547     update_openflow_length(buffer);
 548
 549     return buffer;
 550 }
 551
 552 /* Parses an OFPT_FLOW_MOD with subtype OFPFC_ADD from 'stream' and returns an
 553  * ofpbuf that contains it.  Returns a null pointer if end-of-file is reached
 554  * before reading a flow. */
 555 struct ofpbuf *
 556 parse_ofp_add_flow_file(FILE *stream)
 557 {
 558     struct ofpbuf *b = NULL;
 559     struct ds s = DS_EMPTY_INITIALIZER;
 560
 561     while (!ds_get_line(&s, stream)) {
 562         char *line = ds_cstr(&s);
 563         char *comment;
 564
 565         /* Delete comments. */
 566         comment = strchr(line, '#');
 567         if (comment) {
 568             *comment = '\0';
 569         }
 570
 571         /* Drop empty lines. */
 572         if (line[strspn(line, " \t\n")] == '\0') {
 573             continue;
 574         }
 575
 576         b = parse_ofp_add_flow_str(line);
 577         break;
 578     }
 579     ds_destroy(&s);
 580
 581     return b;
 582 }