+ static uint32_t next_xid = 1;
+ return htonl(next_xid++);
+}
+\f
+/* Basic parsing of OpenFlow messages. */
+
+struct ofputil_msg_type {
+ enum ofputil_msg_code code; /* OFPUTIL_*. */
+ uint32_t value; /* OFPT_*, OFPST_*, NXT_*, or NXST_*. */
+ const char *name; /* e.g. "OFPT_FLOW_REMOVED". */
+ unsigned int min_size; /* Minimum total message size in bytes. */
+ /* 0 if 'min_size' is the exact size that the message must be. Otherwise,
+ * the message may exceed 'min_size' by an even multiple of this value. */
+ unsigned int extra_multiple;
+};
+
+struct ofputil_msg_category {
+ const char *name; /* e.g. "OpenFlow message" */
+ const struct ofputil_msg_type *types;
+ size_t n_types;
+ int missing_error; /* ofp_mkerr() value for missing type. */
+};
+
+static bool
+ofputil_length_ok(const struct ofputil_msg_category *cat,
+ const struct ofputil_msg_type *type,
+ unsigned int size)
+{
+ switch (type->extra_multiple) {
+ case 0:
+ if (size != type->min_size) {
+ VLOG_WARN_RL(&bad_ofmsg_rl, "received %s %s with incorrect "
+ "length %u (expected length %u)",
+ cat->name, type->name, size, type->min_size);
+ return false;
+ }
+ return true;
+
+ case 1:
+ if (size < type->min_size) {
+ VLOG_WARN_RL(&bad_ofmsg_rl, "received %s %s with incorrect "
+ "length %u (expected length at least %u bytes)",
+ cat->name, type->name, size, type->min_size);
+ return false;
+ }
+ return true;
+
+ default:
+ if (size < type->min_size
+ || (size - type->min_size) % type->extra_multiple) {
+ VLOG_WARN_RL(&bad_ofmsg_rl, "received %s %s with incorrect "
+ "length %u (must be exactly %u bytes or longer "
+ "by an integer multiple of %u bytes)",
+ cat->name, type->name, size,
+ type->min_size, type->extra_multiple);
+ return false;
+ }
+ return true;
+ }
+}
+
+static int
+ofputil_lookup_openflow_message(const struct ofputil_msg_category *cat,
+ uint32_t value, unsigned int size,
+ const struct ofputil_msg_type **typep)
+{
+ const struct ofputil_msg_type *type;
+
+ for (type = cat->types; type < &cat->types[cat->n_types]; type++) {
+ if (type->value == value) {
+ if (!ofputil_length_ok(cat, type, size)) {
+ return ofp_mkerr(OFPET_BAD_REQUEST, OFPBRC_BAD_LEN);
+ }
+ *typep = type;
+ return 0;
+ }
+ }
+
+ VLOG_WARN_RL(&bad_ofmsg_rl, "received %s of unknown type %"PRIu32,
+ cat->name, value);
+ return cat->missing_error;
+}
+
+static int
+ofputil_decode_vendor(const struct ofp_header *oh,
+ const struct ofputil_msg_type **typep)
+{
+ BUILD_ASSERT_DECL(sizeof(struct nxt_set_flow_format)
+ != sizeof(struct nxt_flow_mod_table_id));
+
+ static const struct ofputil_msg_type nxt_messages[] = {
+ { OFPUTIL_NXT_ROLE_REQUEST,
+ NXT_ROLE_REQUEST, "NXT_ROLE_REQUEST",
+ sizeof(struct nx_role_request), 0 },
+
+ { OFPUTIL_NXT_ROLE_REPLY,
+ NXT_ROLE_REPLY, "NXT_ROLE_REPLY",
+ sizeof(struct nx_role_request), 0 },
+
+ { OFPUTIL_NXT_SET_FLOW_FORMAT,
+ NXT_SET_FLOW_FORMAT, "NXT_SET_FLOW_FORMAT",
+ sizeof(struct nxt_set_flow_format), 0 },
+
+ { OFPUTIL_NXT_FLOW_MOD,
+ NXT_FLOW_MOD, "NXT_FLOW_MOD",
+ sizeof(struct nx_flow_mod), 8 },
+
+ { OFPUTIL_NXT_FLOW_REMOVED,
+ NXT_FLOW_REMOVED, "NXT_FLOW_REMOVED",
+ sizeof(struct nx_flow_removed), 8 },
+
+ { OFPUTIL_NXT_FLOW_MOD_TABLE_ID,
+ NXT_FLOW_MOD_TABLE_ID, "NXT_FLOW_MOD_TABLE_ID",
+ sizeof(struct nxt_flow_mod_table_id), 0 },
+ };
+
+ static const struct ofputil_msg_category nxt_category = {
+ "Nicira extension message",
+ nxt_messages, ARRAY_SIZE(nxt_messages),
+ OFP_MKERR(OFPET_BAD_REQUEST, OFPBRC_BAD_SUBTYPE)
+ };
+
+ const struct ofp_vendor_header *ovh;
+ const struct nicira_header *nh;
+
+ ovh = (const struct ofp_vendor_header *) oh;
+ if (ovh->vendor != htonl(NX_VENDOR_ID)) {
+ VLOG_WARN_RL(&bad_ofmsg_rl, "received vendor message for unknown "
+ "vendor %"PRIx32, ntohl(ovh->vendor));
+ return ofp_mkerr(OFPET_BAD_REQUEST, OFPBRC_BAD_VENDOR);
+ }
+
+ if (ntohs(ovh->header.length) < sizeof(struct nicira_header)) {
+ VLOG_WARN_RL(&bad_ofmsg_rl, "received Nicira vendor message of "
+ "length %u (expected at least %zu)",
+ ntohs(ovh->header.length), sizeof(struct nicira_header));
+ return ofp_mkerr(OFPET_BAD_REQUEST, OFPBRC_BAD_LEN);
+ }
+
+ nh = (const struct nicira_header *) oh;
+ return ofputil_lookup_openflow_message(&nxt_category, ntohl(nh->subtype),
+ ntohs(oh->length), typep);
+}
+
+static int
+check_nxstats_msg(const struct ofp_header *oh)
+{
+ const struct ofp_stats_msg *osm = (const struct ofp_stats_msg *) oh;
+ ovs_be32 vendor;
+
+ memcpy(&vendor, osm + 1, sizeof vendor);
+ if (vendor != htonl(NX_VENDOR_ID)) {
+ VLOG_WARN_RL(&bad_ofmsg_rl, "received vendor stats message for "
+ "unknown vendor %"PRIx32, ntohl(vendor));
+ return ofp_mkerr(OFPET_BAD_REQUEST, OFPBRC_BAD_VENDOR);
+ }
+
+ if (ntohs(osm->header.length) < sizeof(struct nicira_stats_msg)) {
+ VLOG_WARN_RL(&bad_ofmsg_rl, "truncated Nicira stats message");
+ return ofp_mkerr(OFPET_BAD_REQUEST, OFPBRC_BAD_LEN);
+ }
+
+ return 0;
+}
+
+static int
+ofputil_decode_nxst_request(const struct ofp_header *oh,
+ const struct ofputil_msg_type **typep)
+{
+ static const struct ofputil_msg_type nxst_requests[] = {
+ { OFPUTIL_NXST_FLOW_REQUEST,
+ NXST_FLOW, "NXST_FLOW request",
+ sizeof(struct nx_flow_stats_request), 8 },
+
+ { OFPUTIL_NXST_AGGREGATE_REQUEST,
+ NXST_AGGREGATE, "NXST_AGGREGATE request",
+ sizeof(struct nx_aggregate_stats_request), 8 },
+ };
+
+ static const struct ofputil_msg_category nxst_request_category = {
+ "Nicira extension statistics request",
+ nxst_requests, ARRAY_SIZE(nxst_requests),
+ OFP_MKERR(OFPET_BAD_REQUEST, OFPBRC_BAD_SUBTYPE)
+ };
+
+ const struct nicira_stats_msg *nsm;
+ int error;
+
+ error = check_nxstats_msg(oh);
+ if (error) {
+ return error;
+ }
+
+ nsm = (struct nicira_stats_msg *) oh;
+ return ofputil_lookup_openflow_message(&nxst_request_category,
+ ntohl(nsm->subtype),
+ ntohs(oh->length), typep);
+}
+
+static int
+ofputil_decode_nxst_reply(const struct ofp_header *oh,
+ const struct ofputil_msg_type **typep)
+{
+ static const struct ofputil_msg_type nxst_replies[] = {
+ { OFPUTIL_NXST_FLOW_REPLY,
+ NXST_FLOW, "NXST_FLOW reply",
+ sizeof(struct nicira_stats_msg), 8 },
+
+ { OFPUTIL_NXST_AGGREGATE_REPLY,
+ NXST_AGGREGATE, "NXST_AGGREGATE reply",
+ sizeof(struct nx_aggregate_stats_reply), 0 },
+ };
+
+ static const struct ofputil_msg_category nxst_reply_category = {
+ "Nicira extension statistics reply",
+ nxst_replies, ARRAY_SIZE(nxst_replies),
+ OFP_MKERR(OFPET_BAD_REQUEST, OFPBRC_BAD_SUBTYPE)
+ };
+
+ const struct nicira_stats_msg *nsm;
+ int error;
+
+ error = check_nxstats_msg(oh);
+ if (error) {
+ return error;
+ }
+
+ nsm = (struct nicira_stats_msg *) oh;
+ return ofputil_lookup_openflow_message(&nxst_reply_category,
+ ntohl(nsm->subtype),
+ ntohs(oh->length), typep);
+}
+
+static int
+ofputil_decode_ofpst_request(const struct ofp_header *oh,
+ const struct ofputil_msg_type **typep)
+{
+ static const struct ofputil_msg_type ofpst_requests[] = {
+ { OFPUTIL_OFPST_DESC_REQUEST,
+ OFPST_DESC, "OFPST_DESC request",
+ sizeof(struct ofp_stats_msg), 0 },
+
+ { OFPUTIL_OFPST_FLOW_REQUEST,
+ OFPST_FLOW, "OFPST_FLOW request",
+ sizeof(struct ofp_flow_stats_request), 0 },
+
+ { OFPUTIL_OFPST_AGGREGATE_REQUEST,
+ OFPST_AGGREGATE, "OFPST_AGGREGATE request",
+ sizeof(struct ofp_flow_stats_request), 0 },
+
+ { OFPUTIL_OFPST_TABLE_REQUEST,
+ OFPST_TABLE, "OFPST_TABLE request",
+ sizeof(struct ofp_stats_msg), 0 },
+
+ { OFPUTIL_OFPST_PORT_REQUEST,
+ OFPST_PORT, "OFPST_PORT request",
+ sizeof(struct ofp_port_stats_request), 0 },
+
+ { OFPUTIL_OFPST_QUEUE_REQUEST,
+ OFPST_QUEUE, "OFPST_QUEUE request",
+ sizeof(struct ofp_queue_stats_request), 0 },
+
+ { 0,
+ OFPST_VENDOR, "OFPST_VENDOR request",
+ sizeof(struct ofp_vendor_stats_msg), 1 },
+ };
+
+ static const struct ofputil_msg_category ofpst_request_category = {
+ "OpenFlow statistics",
+ ofpst_requests, ARRAY_SIZE(ofpst_requests),
+ OFP_MKERR(OFPET_BAD_REQUEST, OFPBRC_BAD_STAT)
+ };
+
+ const struct ofp_stats_msg *request = (const struct ofp_stats_msg *) oh;
+ int error;
+
+ error = ofputil_lookup_openflow_message(&ofpst_request_category,
+ ntohs(request->type),
+ ntohs(oh->length), typep);
+ if (!error && request->type == htons(OFPST_VENDOR)) {
+ error = ofputil_decode_nxst_request(oh, typep);
+ }
+ return error;
+}
+
+static int
+ofputil_decode_ofpst_reply(const struct ofp_header *oh,
+ const struct ofputil_msg_type **typep)
+{
+ static const struct ofputil_msg_type ofpst_replies[] = {
+ { OFPUTIL_OFPST_DESC_REPLY,
+ OFPST_DESC, "OFPST_DESC reply",
+ sizeof(struct ofp_desc_stats), 0 },
+
+ { OFPUTIL_OFPST_FLOW_REPLY,
+ OFPST_FLOW, "OFPST_FLOW reply",
+ sizeof(struct ofp_stats_msg), 1 },
+
+ { OFPUTIL_OFPST_AGGREGATE_REPLY,
+ OFPST_AGGREGATE, "OFPST_AGGREGATE reply",
+ sizeof(struct ofp_aggregate_stats_reply), 0 },
+
+ { OFPUTIL_OFPST_TABLE_REPLY,
+ OFPST_TABLE, "OFPST_TABLE reply",
+ sizeof(struct ofp_stats_msg), sizeof(struct ofp_table_stats) },
+
+ { OFPUTIL_OFPST_PORT_REPLY,
+ OFPST_PORT, "OFPST_PORT reply",
+ sizeof(struct ofp_stats_msg), sizeof(struct ofp_port_stats) },
+
+ { OFPUTIL_OFPST_QUEUE_REPLY,
+ OFPST_QUEUE, "OFPST_QUEUE reply",
+ sizeof(struct ofp_stats_msg), sizeof(struct ofp_queue_stats) },
+
+ { 0,
+ OFPST_VENDOR, "OFPST_VENDOR reply",
+ sizeof(struct ofp_vendor_stats_msg), 1 },
+ };
+
+ static const struct ofputil_msg_category ofpst_reply_category = {
+ "OpenFlow statistics",
+ ofpst_replies, ARRAY_SIZE(ofpst_replies),
+ OFP_MKERR(OFPET_BAD_REQUEST, OFPBRC_BAD_STAT)
+ };
+
+ const struct ofp_stats_msg *reply = (const struct ofp_stats_msg *) oh;
+ int error;
+
+ error = ofputil_lookup_openflow_message(&ofpst_reply_category,
+ ntohs(reply->type),
+ ntohs(oh->length), typep);
+ if (!error && reply->type == htons(OFPST_VENDOR)) {
+ error = ofputil_decode_nxst_reply(oh, typep);
+ }
+ return error;
+}
+
+/* Decodes the message type represented by 'oh'. Returns 0 if successful or
+ * an OpenFlow error code constructed with ofp_mkerr() on failure. Either
+ * way, stores in '*typep' a type structure that can be inspected with the
+ * ofputil_msg_type_*() functions.
+ *
+ * oh->length must indicate the correct length of the message (and must be at
+ * least sizeof(struct ofp_header)).
+ *
+ * Success indicates that 'oh' is at least as long as the minimum-length
+ * message of its type. */
+int
+ofputil_decode_msg_type(const struct ofp_header *oh,
+ const struct ofputil_msg_type **typep)
+{
+ static const struct ofputil_msg_type ofpt_messages[] = {
+ { OFPUTIL_OFPT_HELLO,
+ OFPT_HELLO, "OFPT_HELLO",
+ sizeof(struct ofp_hello), 1 },
+
+ { OFPUTIL_OFPT_ERROR,
+ OFPT_ERROR, "OFPT_ERROR",
+ sizeof(struct ofp_error_msg), 1 },
+
+ { OFPUTIL_OFPT_ECHO_REQUEST,
+ OFPT_ECHO_REQUEST, "OFPT_ECHO_REQUEST",
+ sizeof(struct ofp_header), 1 },
+
+ { OFPUTIL_OFPT_ECHO_REPLY,
+ OFPT_ECHO_REPLY, "OFPT_ECHO_REPLY",
+ sizeof(struct ofp_header), 1 },
+
+ { OFPUTIL_OFPT_FEATURES_REQUEST,
+ OFPT_FEATURES_REQUEST, "OFPT_FEATURES_REQUEST",
+ sizeof(struct ofp_header), 0 },
+
+ { OFPUTIL_OFPT_FEATURES_REPLY,
+ OFPT_FEATURES_REPLY, "OFPT_FEATURES_REPLY",
+ sizeof(struct ofp_switch_features), sizeof(struct ofp_phy_port) },
+
+ { OFPUTIL_OFPT_GET_CONFIG_REQUEST,
+ OFPT_GET_CONFIG_REQUEST, "OFPT_GET_CONFIG_REQUEST",
+ sizeof(struct ofp_header), 0 },
+
+ { OFPUTIL_OFPT_GET_CONFIG_REPLY,
+ OFPT_GET_CONFIG_REPLY, "OFPT_GET_CONFIG_REPLY",
+ sizeof(struct ofp_switch_config), 0 },
+
+ { OFPUTIL_OFPT_SET_CONFIG,
+ OFPT_SET_CONFIG, "OFPT_SET_CONFIG",
+ sizeof(struct ofp_switch_config), 0 },
+
+ { OFPUTIL_OFPT_PACKET_IN,
+ OFPT_PACKET_IN, "OFPT_PACKET_IN",
+ offsetof(struct ofp_packet_in, data), 1 },
+
+ { OFPUTIL_OFPT_FLOW_REMOVED,
+ OFPT_FLOW_REMOVED, "OFPT_FLOW_REMOVED",
+ sizeof(struct ofp_flow_removed), 0 },
+
+ { OFPUTIL_OFPT_PORT_STATUS,
+ OFPT_PORT_STATUS, "OFPT_PORT_STATUS",
+ sizeof(struct ofp_port_status), 0 },
+
+ { OFPUTIL_OFPT_PACKET_OUT,
+ OFPT_PACKET_OUT, "OFPT_PACKET_OUT",
+ sizeof(struct ofp_packet_out), 1 },
+
+ { OFPUTIL_OFPT_FLOW_MOD,
+ OFPT_FLOW_MOD, "OFPT_FLOW_MOD",
+ sizeof(struct ofp_flow_mod), 1 },
+
+ { OFPUTIL_OFPT_PORT_MOD,
+ OFPT_PORT_MOD, "OFPT_PORT_MOD",
+ sizeof(struct ofp_port_mod), 0 },
+
+ { 0,
+ OFPT_STATS_REQUEST, "OFPT_STATS_REQUEST",
+ sizeof(struct ofp_stats_msg), 1 },
+
+ { 0,
+ OFPT_STATS_REPLY, "OFPT_STATS_REPLY",
+ sizeof(struct ofp_stats_msg), 1 },
+
+ { OFPUTIL_OFPT_BARRIER_REQUEST,
+ OFPT_BARRIER_REQUEST, "OFPT_BARRIER_REQUEST",
+ sizeof(struct ofp_header), 0 },
+
+ { OFPUTIL_OFPT_BARRIER_REPLY,
+ OFPT_BARRIER_REPLY, "OFPT_BARRIER_REPLY",
+ sizeof(struct ofp_header), 0 },
+
+ { 0,
+ OFPT_VENDOR, "OFPT_VENDOR",
+ sizeof(struct ofp_vendor_header), 1 },
+ };
+
+ static const struct ofputil_msg_category ofpt_category = {
+ "OpenFlow message",
+ ofpt_messages, ARRAY_SIZE(ofpt_messages),
+ OFP_MKERR(OFPET_BAD_REQUEST, OFPBRC_BAD_TYPE)
+ };
+
+ int error;
+
+ error = ofputil_lookup_openflow_message(&ofpt_category, oh->type,
+ ntohs(oh->length), typep);
+ if (!error) {
+ switch (oh->type) {
+ case OFPT_VENDOR:
+ error = ofputil_decode_vendor(oh, typep);
+ break;
+
+ case OFPT_STATS_REQUEST:
+ error = ofputil_decode_ofpst_request(oh, typep);
+ break;
+
+ case OFPT_STATS_REPLY:
+ error = ofputil_decode_ofpst_reply(oh, typep);
+
+ default:
+ break;
+ }
+ }
+ if (error) {
+ static const struct ofputil_msg_type ofputil_invalid_type = {
+ OFPUTIL_MSG_INVALID,
+ 0, "OFPUTIL_MSG_INVALID",
+ 0, 0
+ };
+
+ *typep = &ofputil_invalid_type;
+ }
+ return error;
+}
+
+/* Returns an OFPUTIL_* message type code for 'type'. */
+enum ofputil_msg_code
+ofputil_msg_type_code(const struct ofputil_msg_type *type)
+{
+ return type->code;
+}
+\f
+/* Flow formats. */
+
+bool
+ofputil_flow_format_is_valid(enum nx_flow_format flow_format)
+{
+ switch (flow_format) {
+ case NXFF_OPENFLOW10:
+ case NXFF_NXM:
+ return true;
+ }
+
+ return false;
+}
+
+const char *
+ofputil_flow_format_to_string(enum nx_flow_format flow_format)
+{
+ switch (flow_format) {
+ case NXFF_OPENFLOW10:
+ return "openflow10";
+ case NXFF_NXM:
+ return "nxm";
+ default:
+ NOT_REACHED();
+ }
+}
+
+int
+ofputil_flow_format_from_string(const char *s)
+{
+ return (!strcmp(s, "openflow10") ? NXFF_OPENFLOW10
+ : !strcmp(s, "nxm") ? NXFF_NXM
+ : -1);
+}
+
+static bool
+regs_fully_wildcarded(const struct flow_wildcards *wc)
+{
+ int i;
+
+ for (i = 0; i < FLOW_N_REGS; i++) {
+ if (wc->reg_masks[i] != 0) {
+ return false;
+ }
+ }
+ return true;
+}
+
+/* Returns the minimum nx_flow_format to use for sending 'rule' to a switch
+ * (e.g. to add or remove a flow). Only NXM can handle tunnel IDs, registers,
+ * or fixing the Ethernet multicast bit. Otherwise, it's better to use
+ * NXFF_OPENFLOW10 for backward compatibility. */
+enum nx_flow_format
+ofputil_min_flow_format(const struct cls_rule *rule)
+{
+ const struct flow_wildcards *wc = &rule->wc;
+
+ /* Only NXM supports separately wildcards the Ethernet multicast bit. */
+ if (!(wc->wildcards & FWW_DL_DST) != !(wc->wildcards & FWW_ETH_MCAST)) {
+ return NXFF_NXM;
+ }
+
+ /* Only NXM supports matching ARP hardware addresses. */
+ if (!(wc->wildcards & FWW_ARP_SHA) || !(wc->wildcards & FWW_ARP_THA)) {
+ return NXFF_NXM;
+ }
+
+ /* Only NXM supports matching IPv6 traffic. */
+ if (!(wc->wildcards & FWW_DL_TYPE)
+ && (rule->flow.dl_type == htons(ETH_TYPE_IPV6))) {
+ return NXFF_NXM;
+ }
+
+ /* Only NXM supports matching registers. */
+ if (!regs_fully_wildcarded(wc)) {
+ return NXFF_NXM;
+ }
+
+ /* Only NXM supports matching tun_id. */
+ if (wc->tun_id_mask != htonll(0)) {
+ return NXFF_NXM;
+ }
+
+ /* Other formats can express this rule. */
+ return NXFF_OPENFLOW10;
+}
+
+/* Returns an OpenFlow message that can be used to set the flow format to
+ * 'flow_format'. */
+struct ofpbuf *
+ofputil_make_set_flow_format(enum nx_flow_format flow_format)
+{
+ struct nxt_set_flow_format *sff;
+ struct ofpbuf *msg;
+
+ sff = make_nxmsg(sizeof *sff, NXT_SET_FLOW_FORMAT, &msg);
+ sff->format = htonl(flow_format);
+
+ return msg;
+}
+
+/* Returns an OpenFlow message that can be used to turn the flow_mod_table_id
+ * extension on or off (according to 'flow_mod_table_id'). */
+struct ofpbuf *
+ofputil_make_flow_mod_table_id(bool flow_mod_table_id)
+{
+ struct nxt_flow_mod_table_id *nfmti;
+ struct ofpbuf *msg;
+
+ nfmti = make_nxmsg(sizeof *nfmti, NXT_FLOW_MOD_TABLE_ID, &msg);
+ nfmti->set = flow_mod_table_id;
+ return msg;
+}
+
+/* Converts an OFPT_FLOW_MOD or NXT_FLOW_MOD message 'oh' into an abstract
+ * flow_mod in 'fm'. Returns 0 if successful, otherwise an OpenFlow error
+ * code.
+ *
+ * 'flow_mod_table_id' should be true if the NXT_FLOW_MOD_TABLE_ID extension is
+ * enabled, false otherwise.
+ *
+ * Does not validate the flow_mod actions. */
+int
+ofputil_decode_flow_mod(struct ofputil_flow_mod *fm,
+ const struct ofp_header *oh, bool flow_mod_table_id)
+{
+ const struct ofputil_msg_type *type;
+ uint16_t command;
+ struct ofpbuf b;
+
+ ofpbuf_use_const(&b, oh, ntohs(oh->length));
+
+ ofputil_decode_msg_type(oh, &type);
+ if (ofputil_msg_type_code(type) == OFPUTIL_OFPT_FLOW_MOD) {
+ /* Standard OpenFlow flow_mod. */
+ const struct ofp_flow_mod *ofm;
+ uint16_t priority;
+ int error;
+
+ /* Dissect the message. */
+ ofm = ofpbuf_pull(&b, sizeof *ofm);
+ error = ofputil_pull_actions(&b, b.size, &fm->actions, &fm->n_actions);
+ if (error) {
+ return error;
+ }
+
+ /* Set priority based on original wildcards. Normally we'd allow
+ * ofputil_cls_rule_from_match() to do this for us, but
+ * ofputil_normalize_rule() can put wildcards where the original flow
+ * didn't have them. */
+ priority = ntohs(ofm->priority);
+ if (!(ofm->match.wildcards & htonl(OFPFW_ALL))) {
+ priority = UINT16_MAX;
+ }
+
+ /* Translate the rule. */
+ ofputil_cls_rule_from_match(&ofm->match, priority, &fm->cr);
+ ofputil_normalize_rule(&fm->cr, NXFF_OPENFLOW10);
+
+ /* Translate the message. */
+ fm->cookie = ofm->cookie;
+ command = ntohs(ofm->command);
+ fm->idle_timeout = ntohs(ofm->idle_timeout);
+ fm->hard_timeout = ntohs(ofm->hard_timeout);
+ fm->buffer_id = ntohl(ofm->buffer_id);
+ fm->out_port = ntohs(ofm->out_port);
+ fm->flags = ntohs(ofm->flags);
+ } else if (ofputil_msg_type_code(type) == OFPUTIL_NXT_FLOW_MOD) {
+ /* Nicira extended flow_mod. */
+ const struct nx_flow_mod *nfm;
+ int error;
+
+ /* Dissect the message. */
+ nfm = ofpbuf_pull(&b, sizeof *nfm);
+ error = nx_pull_match(&b, ntohs(nfm->match_len), ntohs(nfm->priority),
+ &fm->cr);
+ if (error) {
+ return error;
+ }
+ error = ofputil_pull_actions(&b, b.size, &fm->actions, &fm->n_actions);
+ if (error) {
+ return error;
+ }
+
+ /* Translate the message. */
+ fm->cookie = nfm->cookie;
+ command = ntohs(nfm->command);
+ fm->idle_timeout = ntohs(nfm->idle_timeout);
+ fm->hard_timeout = ntohs(nfm->hard_timeout);
+ fm->buffer_id = ntohl(nfm->buffer_id);
+ fm->out_port = ntohs(nfm->out_port);
+ fm->flags = ntohs(nfm->flags);
+ } else {
+ NOT_REACHED();
+ }
+
+ if (flow_mod_table_id) {
+ fm->command = command & 0xff;
+ fm->table_id = command >> 8;
+ } else {
+ fm->command = command;
+ fm->table_id = 0xff;
+ }
+
+ return 0;
+}
+
+/* Converts 'fm' into an OFPT_FLOW_MOD or NXT_FLOW_MOD message according to
+ * 'flow_format' and returns the message.
+ *
+ * 'flow_mod_table_id' should be true if the NXT_FLOW_MOD_TABLE_ID extension is
+ * enabled, false otherwise. */
+struct ofpbuf *
+ofputil_encode_flow_mod(const struct ofputil_flow_mod *fm,
+ enum nx_flow_format flow_format,
+ bool flow_mod_table_id)
+{
+ size_t actions_len = fm->n_actions * sizeof *fm->actions;
+ struct ofpbuf *msg;
+ uint16_t command;
+
+ command = (flow_mod_table_id
+ ? (fm->command & 0xff) | (fm->table_id << 8)
+ : fm->command);
+
+ if (flow_format == NXFF_OPENFLOW10) {
+ struct ofp_flow_mod *ofm;
+
+ msg = ofpbuf_new(sizeof *ofm + actions_len);
+ ofm = put_openflow(sizeof *ofm, OFPT_FLOW_MOD, msg);
+ ofputil_cls_rule_to_match(&fm->cr, &ofm->match);
+ ofm->cookie = fm->cookie;
+ ofm->command = htons(command);
+ ofm->idle_timeout = htons(fm->idle_timeout);
+ ofm->hard_timeout = htons(fm->hard_timeout);
+ ofm->priority = htons(fm->cr.priority);
+ ofm->buffer_id = htonl(fm->buffer_id);
+ ofm->out_port = htons(fm->out_port);
+ ofm->flags = htons(fm->flags);
+ } else if (flow_format == NXFF_NXM) {
+ struct nx_flow_mod *nfm;
+ int match_len;
+
+ msg = ofpbuf_new(sizeof *nfm + NXM_TYPICAL_LEN + actions_len);
+ put_nxmsg(sizeof *nfm, NXT_FLOW_MOD, msg);
+ match_len = nx_put_match(msg, &fm->cr);
+
+ nfm = msg->data;
+ nfm->cookie = fm->cookie;
+ nfm->command = htons(command);
+ nfm->idle_timeout = htons(fm->idle_timeout);
+ nfm->hard_timeout = htons(fm->hard_timeout);
+ nfm->priority = htons(fm->cr.priority);
+ nfm->buffer_id = htonl(fm->buffer_id);
+ nfm->out_port = htons(fm->out_port);
+ nfm->flags = htons(fm->flags);
+ nfm->match_len = htons(match_len);
+ } else {
+ NOT_REACHED();
+ }
+
+ ofpbuf_put(msg, fm->actions, actions_len);
+ update_openflow_length(msg);
+ return msg;
+}
+
+static int
+ofputil_decode_ofpst_flow_request(struct flow_stats_request *fsr,
+ const struct ofp_header *oh,
+ bool aggregate)
+{
+ const struct ofp_flow_stats_request *ofsr =
+ (const struct ofp_flow_stats_request *) oh;
+
+ fsr->aggregate = aggregate;
+ ofputil_cls_rule_from_match(&ofsr->match, 0, &fsr->match);
+ fsr->out_port = ntohs(ofsr->out_port);
+ fsr->table_id = ofsr->table_id;
+
+ return 0;
+}
+
+static int
+ofputil_decode_nxst_flow_request(struct flow_stats_request *fsr,
+ const struct ofp_header *oh,
+ bool aggregate)
+{
+ const struct nx_flow_stats_request *nfsr;
+ struct ofpbuf b;
+ int error;
+
+ ofpbuf_use_const(&b, oh, ntohs(oh->length));
+
+ nfsr = ofpbuf_pull(&b, sizeof *nfsr);
+ error = nx_pull_match(&b, ntohs(nfsr->match_len), 0, &fsr->match);
+ if (error) {
+ return error;
+ }
+ if (b.size) {
+ return ofp_mkerr(OFPET_BAD_REQUEST, OFPBRC_BAD_LEN);
+ }
+
+ fsr->aggregate = aggregate;
+ fsr->out_port = ntohs(nfsr->out_port);
+ fsr->table_id = nfsr->table_id;
+
+ return 0;
+}
+
+/* Converts an OFPST_FLOW, OFPST_AGGREGATE, NXST_FLOW, or NXST_AGGREGATE
+ * request 'oh', into an abstract flow_stats_request in 'fsr'. Returns 0 if
+ * successful, otherwise an OpenFlow error code. */
+int
+ofputil_decode_flow_stats_request(struct flow_stats_request *fsr,
+ const struct ofp_header *oh)
+{
+ const struct ofputil_msg_type *type;
+ struct ofpbuf b;
+ int code;
+
+ ofpbuf_use_const(&b, oh, ntohs(oh->length));
+
+ ofputil_decode_msg_type(oh, &type);
+ code = ofputil_msg_type_code(type);
+ switch (code) {
+ case OFPUTIL_OFPST_FLOW_REQUEST:
+ return ofputil_decode_ofpst_flow_request(fsr, oh, false);
+
+ case OFPUTIL_OFPST_AGGREGATE_REQUEST:
+ return ofputil_decode_ofpst_flow_request(fsr, oh, true);
+
+ case OFPUTIL_NXST_FLOW_REQUEST:
+ return ofputil_decode_nxst_flow_request(fsr, oh, false);
+
+ case OFPUTIL_NXST_AGGREGATE_REQUEST:
+ return ofputil_decode_nxst_flow_request(fsr, oh, true);
+
+ default:
+ /* Hey, the caller lied. */
+ NOT_REACHED();
+ }
+}
+
+/* Converts abstract flow_stats_request 'fsr' into an OFPST_FLOW,
+ * OFPST_AGGREGATE, NXST_FLOW, or NXST_AGGREGATE request 'oh' according to
+ * 'flow_format', and returns the message. */
+struct ofpbuf *
+ofputil_encode_flow_stats_request(const struct flow_stats_request *fsr,
+ enum nx_flow_format flow_format)
+{
+ struct ofpbuf *msg;
+
+ if (flow_format == NXFF_OPENFLOW10) {
+ struct ofp_flow_stats_request *ofsr;
+ int type;
+
+ type = fsr->aggregate ? OFPST_AGGREGATE : OFPST_FLOW;
+ ofsr = ofputil_make_stats_request(sizeof *ofsr, type, 0, &msg);
+ ofputil_cls_rule_to_match(&fsr->match, &ofsr->match);
+ ofsr->table_id = fsr->table_id;
+ ofsr->out_port = htons(fsr->out_port);
+ } else if (flow_format == NXFF_NXM) {
+ struct nx_flow_stats_request *nfsr;
+ int match_len;
+ int subtype;
+
+ subtype = fsr->aggregate ? NXST_AGGREGATE : NXST_FLOW;
+ ofputil_make_stats_request(sizeof *nfsr, OFPST_VENDOR, subtype, &msg);
+ match_len = nx_put_match(msg, &fsr->match);
+
+ nfsr = msg->data;
+ nfsr->out_port = htons(fsr->out_port);
+ nfsr->match_len = htons(match_len);
+ nfsr->table_id = fsr->table_id;
+ } else {
+ NOT_REACHED();
+ }
+
+ return msg;