+ 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;
+}
+
+/* Converts an OFPST_FLOW or NXST_FLOW reply in 'msg' into an abstract
+ * ofputil_flow_stats in 'fs'.
+ *
+ * Multiple OFPST_FLOW or NXST_FLOW replies can be packed into a single
+ * OpenFlow message. Calling this function multiple times for a single 'msg'
+ * iterates through the replies. The caller must initially leave 'msg''s layer
+ * pointers null and not modify them between calls.
+ *
+ * Returns 0 if successful, EOF if no replies were left in this 'msg',
+ * otherwise a positive errno value. */
+int
+ofputil_decode_flow_stats_reply(struct ofputil_flow_stats *fs,
+ struct ofpbuf *msg)
+{
+ const struct ofputil_msg_type *type;
+ int code;
+
+ ofputil_decode_msg_type(msg->l2 ? msg->l2 : msg->data, &type);
+ code = ofputil_msg_type_code(type);
+ if (!msg->l2) {
+ msg->l2 = msg->data;
+ if (code == OFPUTIL_OFPST_FLOW_REPLY) {
+ ofpbuf_pull(msg, sizeof(struct ofp_stats_msg));
+ } else if (code == OFPUTIL_NXST_FLOW_REPLY) {
+ ofpbuf_pull(msg, sizeof(struct nicira_stats_msg));
+ } else {
+ NOT_REACHED();
+ }
+ }
+
+ if (!msg->size) {
+ return EOF;
+ } else if (code == OFPUTIL_OFPST_FLOW_REPLY) {
+ const struct ofp_flow_stats *ofs;
+ size_t length;
+
+ ofs = ofpbuf_try_pull(msg, sizeof *ofs);
+ if (!ofs) {
+ VLOG_WARN_RL(&bad_ofmsg_rl, "OFPST_FLOW reply has %zu leftover "
+ "bytes at end", msg->size);
+ return EINVAL;
+ }
+
+ length = ntohs(ofs->length);
+ if (length < sizeof *ofs) {
+ VLOG_WARN_RL(&bad_ofmsg_rl, "OFPST_FLOW reply claims invalid "
+ "length %zu", length);
+ return EINVAL;
+ }
+
+ if (ofputil_pull_actions(msg, length - sizeof *ofs,
+ &fs->actions, &fs->n_actions)) {
+ return EINVAL;
+ }
+
+ fs->cookie = get_32aligned_be64(&ofs->cookie);
+ ofputil_cls_rule_from_match(&ofs->match, ntohs(ofs->priority),
+ &fs->rule);
+ fs->table_id = ofs->table_id;
+ fs->duration_sec = ntohl(ofs->duration_sec);
+ fs->duration_nsec = ntohl(ofs->duration_nsec);
+ fs->idle_timeout = ntohs(ofs->idle_timeout);
+ fs->hard_timeout = ntohs(ofs->hard_timeout);
+ fs->packet_count = ntohll(get_32aligned_be64(&ofs->packet_count));
+ fs->byte_count = ntohll(get_32aligned_be64(&ofs->byte_count));
+ } else if (code == OFPUTIL_NXST_FLOW_REPLY) {
+ const struct nx_flow_stats *nfs;
+ size_t match_len, length;
+
+ nfs = ofpbuf_try_pull(msg, sizeof *nfs);
+ if (!nfs) {
+ VLOG_WARN_RL(&bad_ofmsg_rl, "NXST_FLOW reply has %zu leftover "
+ "bytes at end", msg->size);
+ return EINVAL;
+ }
+
+ length = ntohs(nfs->length);
+ match_len = ntohs(nfs->match_len);
+ if (length < sizeof *nfs + ROUND_UP(match_len, 8)) {
+ VLOG_WARN_RL(&bad_ofmsg_rl, "NXST_FLOW reply with match_len=%zu "
+ "claims invalid length %zu", match_len, length);
+ return EINVAL;
+ }
+ if (nx_pull_match(msg, match_len, ntohs(nfs->priority), &fs->rule)) {
+ return EINVAL;
+ }
+
+ if (ofputil_pull_actions(msg,
+ length - sizeof *nfs - ROUND_UP(match_len, 8),
+ &fs->actions, &fs->n_actions)) {
+ return EINVAL;
+ }
+
+ fs->cookie = nfs->cookie;
+ fs->table_id = nfs->table_id;
+ fs->duration_sec = ntohl(nfs->duration_sec);
+ fs->duration_nsec = ntohl(nfs->duration_nsec);
+ fs->idle_timeout = ntohs(nfs->idle_timeout);
+ fs->hard_timeout = ntohs(nfs->hard_timeout);
+ fs->packet_count = ntohll(nfs->packet_count);
+ fs->byte_count = ntohll(nfs->byte_count);
+ } else {
+ NOT_REACHED();
+ }
+
+ return 0;
+}
+
+/* Returns 'count' unchanged except that UINT64_MAX becomes 0.
+ *
+ * We use this in situations where OVS internally uses UINT64_MAX to mean
+ * "value unknown" but OpenFlow 1.0 does not define any unknown value. */
+static uint64_t
+unknown_to_zero(uint64_t count)
+{
+ return count != UINT64_MAX ? count : 0;
+}
+
+/* Appends an OFPST_FLOW or NXST_FLOW reply that contains the data in 'fs' to
+ * those already present in the list of ofpbufs in 'replies'. 'replies' should
+ * have been initialized with ofputil_start_stats_reply(). */
+void
+ofputil_append_flow_stats_reply(const struct ofputil_flow_stats *fs,
+ struct list *replies)
+{
+ size_t act_len = fs->n_actions * sizeof *fs->actions;
+ const struct ofp_stats_msg *osm;
+
+ osm = ofpbuf_from_list(list_back(replies))->data;
+ if (osm->type == htons(OFPST_FLOW)) {
+ size_t len = offsetof(struct ofp_flow_stats, actions) + act_len;
+ struct ofp_flow_stats *ofs;
+
+ ofs = ofputil_append_stats_reply(len, replies);
+ ofs->length = htons(len);
+ ofs->table_id = fs->table_id;
+ ofs->pad = 0;
+ ofputil_cls_rule_to_match(&fs->rule, &ofs->match);
+ ofs->duration_sec = htonl(fs->duration_sec);
+ ofs->duration_nsec = htonl(fs->duration_nsec);
+ ofs->priority = htons(fs->rule.priority);
+ ofs->idle_timeout = htons(fs->idle_timeout);
+ ofs->hard_timeout = htons(fs->hard_timeout);
+ memset(ofs->pad2, 0, sizeof ofs->pad2);
+ put_32aligned_be64(&ofs->cookie, fs->cookie);
+ put_32aligned_be64(&ofs->packet_count,
+ htonll(unknown_to_zero(fs->packet_count)));
+ put_32aligned_be64(&ofs->byte_count,
+ htonll(unknown_to_zero(fs->byte_count)));
+ memcpy(ofs->actions, fs->actions, act_len);
+ } else if (osm->type == htons(OFPST_VENDOR)) {
+ struct nx_flow_stats *nfs;
+ struct ofpbuf *msg;
+ size_t start_len;
+
+ msg = ofputil_reserve_stats_reply(
+ sizeof *nfs + NXM_MAX_LEN + act_len, replies);
+ start_len = msg->size;
+
+ nfs = ofpbuf_put_uninit(msg, sizeof *nfs);
+ nfs->table_id = fs->table_id;
+ nfs->pad = 0;
+ nfs->duration_sec = htonl(fs->duration_sec);
+ nfs->duration_nsec = htonl(fs->duration_nsec);
+ nfs->priority = htons(fs->rule.priority);
+ nfs->idle_timeout = htons(fs->idle_timeout);
+ nfs->hard_timeout = htons(fs->hard_timeout);
+ nfs->match_len = htons(nx_put_match(msg, &fs->rule));
+ memset(nfs->pad2, 0, sizeof nfs->pad2);
+ nfs->cookie = fs->cookie;
+ nfs->packet_count = htonll(fs->packet_count);
+ nfs->byte_count = htonll(fs->byte_count);
+ ofpbuf_put(msg, fs->actions, act_len);
+ nfs->length = htons(msg->size - start_len);
+ } else {
+ NOT_REACHED();
+ }
+}
+
+/* Converts abstract ofputil_aggregate_stats 'stats' into an OFPST_AGGREGATE or
+ * NXST_AGGREGATE reply according to 'flow_format', and returns the message. */
+struct ofpbuf *
+ofputil_encode_aggregate_stats_reply(
+ const struct ofputil_aggregate_stats *stats,
+ const struct ofp_stats_msg *request)
+{
+ struct ofpbuf *msg;
+
+ if (request->type == htons(OFPST_AGGREGATE)) {
+ struct ofp_aggregate_stats_reply *asr;
+
+ asr = ofputil_make_stats_reply(sizeof *asr, request, &msg);
+ put_32aligned_be64(&asr->packet_count,
+ htonll(unknown_to_zero(stats->packet_count)));
+ put_32aligned_be64(&asr->byte_count,
+ htonll(unknown_to_zero(stats->byte_count)));
+ asr->flow_count = htonl(stats->flow_count);
+ } else if (request->type == htons(OFPST_VENDOR)) {
+ struct nx_aggregate_stats_reply *nasr;
+
+ nasr = ofputil_make_stats_reply(sizeof *nasr, request, &msg);
+ assert(nasr->nsm.subtype == htonl(NXST_AGGREGATE));
+ nasr->packet_count = htonll(stats->packet_count);
+ nasr->byte_count = htonll(stats->byte_count);
+ nasr->flow_count = htonl(stats->flow_count);
+ } else {
+ NOT_REACHED();
+ }
+
+ return msg;
+}
+
+/* Converts an OFPT_FLOW_REMOVED or NXT_FLOW_REMOVED message 'oh' into an
+ * abstract ofputil_flow_removed in 'fr'. Returns 0 if successful, otherwise
+ * an OpenFlow error code. */
+int
+ofputil_decode_flow_removed(struct ofputil_flow_removed *fr,
+ const struct ofp_header *oh)
+{
+ const struct ofputil_msg_type *type;
+ enum ofputil_msg_code code;
+
+ ofputil_decode_msg_type(oh, &type);
+ code = ofputil_msg_type_code(type);
+ if (code == OFPUTIL_OFPT_FLOW_REMOVED) {
+ const struct ofp_flow_removed *ofr;
+
+ ofr = (const struct ofp_flow_removed *) oh;
+ ofputil_cls_rule_from_match(&ofr->match, ntohs(ofr->priority),
+ &fr->rule);
+ fr->cookie = ofr->cookie;
+ fr->reason = ofr->reason;
+ fr->duration_sec = ntohl(ofr->duration_sec);
+ fr->duration_nsec = ntohl(ofr->duration_nsec);
+ fr->idle_timeout = ntohs(ofr->idle_timeout);
+ fr->packet_count = ntohll(ofr->packet_count);
+ fr->byte_count = ntohll(ofr->byte_count);
+ } else if (code == OFPUTIL_NXT_FLOW_REMOVED) {
+ struct nx_flow_removed *nfr;
+ struct ofpbuf b;
+ int error;
+
+ ofpbuf_use_const(&b, oh, ntohs(oh->length));
+
+ nfr = ofpbuf_pull(&b, sizeof *nfr);
+ error = nx_pull_match(&b, ntohs(nfr->match_len), ntohs(nfr->priority),
+ &fr->rule);
+ if (error) {
+ return error;
+ }
+ if (b.size) {
+ return ofp_mkerr(OFPET_BAD_REQUEST, OFPBRC_BAD_LEN);
+ }
+
+ fr->cookie = nfr->cookie;
+ fr->reason = nfr->reason;
+ fr->duration_sec = ntohl(nfr->duration_sec);
+ fr->duration_nsec = ntohl(nfr->duration_nsec);
+ fr->idle_timeout = ntohs(nfr->idle_timeout);
+ fr->packet_count = ntohll(nfr->packet_count);
+ fr->byte_count = ntohll(nfr->byte_count);
+ } else {
+ NOT_REACHED();
+ }
+
+ return 0;
+}
+
+/* Converts abstract ofputil_flow_removed 'fr' into an OFPT_FLOW_REMOVED or
+ * NXT_FLOW_REMOVED message 'oh' according to 'flow_format', and returns the
+ * message. */
+struct ofpbuf *
+ofputil_encode_flow_removed(const struct ofputil_flow_removed *fr,
+ enum nx_flow_format flow_format)
+{
+ struct ofpbuf *msg;
+
+ if (flow_format == NXFF_OPENFLOW10) {
+ struct ofp_flow_removed *ofr;
+
+ ofr = make_openflow_xid(sizeof *ofr, OFPT_FLOW_REMOVED, htonl(0),
+ &msg);
+ ofputil_cls_rule_to_match(&fr->rule, &ofr->match);
+ ofr->cookie = fr->cookie;
+ ofr->priority = htons(fr->rule.priority);
+ ofr->reason = fr->reason;
+ ofr->duration_sec = htonl(fr->duration_sec);
+ ofr->duration_nsec = htonl(fr->duration_nsec);
+ ofr->idle_timeout = htons(fr->idle_timeout);
+ ofr->packet_count = htonll(unknown_to_zero(fr->packet_count));
+ ofr->byte_count = htonll(unknown_to_zero(fr->byte_count));
+ } else if (flow_format == NXFF_NXM) {
+ struct nx_flow_removed *nfr;
+ int match_len;
+
+ make_nxmsg_xid(sizeof *nfr, NXT_FLOW_REMOVED, htonl(0), &msg);
+ match_len = nx_put_match(msg, &fr->rule);
+
+ nfr = msg->data;
+ nfr->cookie = fr->cookie;
+ nfr->priority = htons(fr->rule.priority);
+ nfr->reason = fr->reason;
+ nfr->duration_sec = htonl(fr->duration_sec);
+ nfr->duration_nsec = htonl(fr->duration_nsec);
+ nfr->idle_timeout = htons(fr->idle_timeout);
+ nfr->match_len = htons(match_len);
+ nfr->packet_count = htonll(fr->packet_count);
+ nfr->byte_count = htonll(fr->byte_count);
+ } else {
+ NOT_REACHED();
+ }
+
+ return msg;
+}
+
+/* Converts abstract ofputil_packet_in 'pin' into an OFPT_PACKET_IN message
+ * and returns the message.
+ *
+ * If 'rw_packet' is NULL, the caller takes ownership of the newly allocated
+ * returned ofpbuf.
+ *
+ * If 'rw_packet' is nonnull, then it must contain the same data as
+ * pin->packet. 'rw_packet' is allowed to be the same ofpbuf as pin->packet.
+ * It is modified in-place into an OFPT_PACKET_IN message according to 'pin',
+ * and then ofputil_encode_packet_in() returns 'rw_packet'. If 'rw_packet' has
+ * enough headroom to insert a "struct ofp_packet_in", this is more efficient
+ * than ofputil_encode_packet_in() because it does not copy the packet
+ * payload. */
+struct ofpbuf *
+ofputil_encode_packet_in(const struct ofputil_packet_in *pin,
+ struct ofpbuf *rw_packet)
+{
+ int total_len = pin->packet->size;
+ struct ofp_packet_in *opi;
+
+ if (rw_packet) {
+ if (pin->send_len < rw_packet->size) {
+ rw_packet->size = pin->send_len;
+ }
+ } else {
+ rw_packet = ofpbuf_clone_data_with_headroom(
+ pin->packet->data, MIN(pin->send_len, pin->packet->size),
+ offsetof(struct ofp_packet_in, data));
+ }
+
+ /* Add OFPT_PACKET_IN. */
+ opi = ofpbuf_push_zeros(rw_packet, offsetof(struct ofp_packet_in, data));
+ opi->header.version = OFP_VERSION;
+ opi->header.type = OFPT_PACKET_IN;
+ opi->total_len = htons(total_len);
+ opi->in_port = htons(pin->in_port);
+ opi->reason = pin->reason;
+ opi->buffer_id = htonl(pin->buffer_id);
+ update_openflow_length(rw_packet);
+
+ return rw_packet;
+}
+
+/* Returns a string representing the message type of 'type'. The string is the
+ * enumeration constant for the type, e.g. "OFPT_HELLO". For statistics
+ * messages, the constant is followed by "request" or "reply",
+ * e.g. "OFPST_AGGREGATE reply". */
+const char *
+ofputil_msg_type_name(const struct ofputil_msg_type *type)
+{
+ return type->name;
+}
+\f
+/* Allocates and stores in '*bufferp' a new ofpbuf with a size of
+ * 'openflow_len', starting with an OpenFlow header with the given 'type' and
+ * an arbitrary transaction id. Allocated bytes beyond the header, if any, are
+ * zeroed.
+ *
+ * The caller is responsible for freeing '*bufferp' when it is no longer
+ * needed.
+ *
+ * The OpenFlow header length is initially set to 'openflow_len'; if the
+ * message is later extended, the length should be updated with
+ * update_openflow_length() before sending.
+ *
+ * Returns the header. */
+void *
+make_openflow(size_t openflow_len, uint8_t type, struct ofpbuf **bufferp)
+{
+ *bufferp = ofpbuf_new(openflow_len);
+ return put_openflow_xid(openflow_len, type, alloc_xid(), *bufferp);
+}
+
+/* Similar to make_openflow() but creates a Nicira vendor extension message
+ * with the specific 'subtype'. 'subtype' should be in host byte order. */
+void *
+make_nxmsg(size_t openflow_len, uint32_t subtype, struct ofpbuf **bufferp)
+{
+ return make_nxmsg_xid(openflow_len, subtype, alloc_xid(), bufferp);
+}
+
+/* Allocates and stores in '*bufferp' a new ofpbuf with a size of
+ * 'openflow_len', starting with an OpenFlow header with the given 'type' and
+ * transaction id 'xid'. Allocated bytes beyond the header, if any, are
+ * zeroed.
+ *
+ * The caller is responsible for freeing '*bufferp' when it is no longer
+ * needed.
+ *
+ * The OpenFlow header length is initially set to 'openflow_len'; if the
+ * message is later extended, the length should be updated with
+ * update_openflow_length() before sending.
+ *
+ * Returns the header. */
+void *
+make_openflow_xid(size_t openflow_len, uint8_t type, ovs_be32 xid,
+ struct ofpbuf **bufferp)
+{
+ *bufferp = ofpbuf_new(openflow_len);
+ return put_openflow_xid(openflow_len, type, xid, *bufferp);
+}
+
+/* Similar to make_openflow_xid() but creates a Nicira vendor extension message
+ * with the specific 'subtype'. 'subtype' should be in host byte order. */
+void *
+make_nxmsg_xid(size_t openflow_len, uint32_t subtype, ovs_be32 xid,
+ struct ofpbuf **bufferp)
+{
+ *bufferp = ofpbuf_new(openflow_len);
+ return put_nxmsg_xid(openflow_len, subtype, xid, *bufferp);
+}
+
+/* Appends 'openflow_len' bytes to 'buffer', starting with an OpenFlow header
+ * with the given 'type' and an arbitrary transaction id. Allocated bytes
+ * beyond the header, if any, are zeroed.
+ *
+ * The OpenFlow header length is initially set to 'openflow_len'; if the
+ * message is later extended, the length should be updated with
+ * update_openflow_length() before sending.
+ *
+ * Returns the header. */
+void *
+put_openflow(size_t openflow_len, uint8_t type, struct ofpbuf *buffer)
+{
+ return put_openflow_xid(openflow_len, type, alloc_xid(), buffer);
+}
+
+/* Appends 'openflow_len' bytes to 'buffer', starting with an OpenFlow header
+ * with the given 'type' and an transaction id 'xid'. Allocated bytes beyond
+ * the header, if any, are zeroed.
+ *
+ * The OpenFlow header length is initially set to 'openflow_len'; if the
+ * message is later extended, the length should be updated with
+ * update_openflow_length() before sending.
+ *
+ * Returns the header. */
+void *
+put_openflow_xid(size_t openflow_len, uint8_t type, ovs_be32 xid,
+ struct ofpbuf *buffer)
+{
+ struct ofp_header *oh;
+
+ assert(openflow_len >= sizeof *oh);
+ assert(openflow_len <= UINT16_MAX);
+
+ oh = ofpbuf_put_uninit(buffer, openflow_len);
+ oh->version = OFP_VERSION;
+ oh->type = type;
+ oh->length = htons(openflow_len);
+ oh->xid = xid;
+ memset(oh + 1, 0, openflow_len - sizeof *oh);
+ return oh;
+}
+
+/* Similar to put_openflow() but append a Nicira vendor extension message with
+ * the specific 'subtype'. 'subtype' should be in host byte order. */
+void *
+put_nxmsg(size_t openflow_len, uint32_t subtype, struct ofpbuf *buffer)
+{
+ return put_nxmsg_xid(openflow_len, subtype, alloc_xid(), buffer);
+}
+
+/* Similar to put_openflow_xid() but append a Nicira vendor extension message
+ * with the specific 'subtype'. 'subtype' should be in host byte order. */
+void *
+put_nxmsg_xid(size_t openflow_len, uint32_t subtype, ovs_be32 xid,
+ struct ofpbuf *buffer)
+{
+ struct nicira_header *nxh;
+
+ nxh = put_openflow_xid(openflow_len, OFPT_VENDOR, xid, buffer);
+ nxh->vendor = htonl(NX_VENDOR_ID);
+ nxh->subtype = htonl(subtype);
+ return nxh;
+}
+
+/* Updates the 'length' field of the OpenFlow message in 'buffer' to
+ * 'buffer->size'. */
+void
+update_openflow_length(struct ofpbuf *buffer)
+{
+ struct ofp_header *oh = ofpbuf_at_assert(buffer, 0, sizeof *oh);
+ oh->length = htons(buffer->size);
+}
+
+static void
+put_stats__(ovs_be32 xid, uint8_t ofp_type,
+ ovs_be16 ofpst_type, ovs_be32 nxst_subtype,
+ struct ofpbuf *msg)
+{
+ if (ofpst_type == htons(OFPST_VENDOR)) {
+ struct nicira_stats_msg *nsm;
+
+ nsm = put_openflow_xid(sizeof *nsm, ofp_type, xid, msg);
+ nsm->vsm.osm.type = ofpst_type;
+ nsm->vsm.vendor = htonl(NX_VENDOR_ID);
+ nsm->subtype = nxst_subtype;
+ } else {
+ struct ofp_stats_msg *osm;
+
+ osm = put_openflow_xid(sizeof *osm, ofp_type, xid, msg);
+ osm->type = ofpst_type;
+ }
+}
+
+/* Creates a statistics request message with total length 'openflow_len'
+ * (including all headers) and the given 'ofpst_type', and stores the buffer
+ * containing the new message in '*bufferp'. If 'ofpst_type' is OFPST_VENDOR
+ * then 'nxst_subtype' is used as the Nicira vendor extension statistics
+ * subtype (otherwise 'nxst_subtype' is ignored).
+ *
+ * Initializes bytes following the headers to all-bits-zero.
+ *
+ * Returns the first byte of the new message. */
+void *
+ofputil_make_stats_request(size_t openflow_len, uint16_t ofpst_type,
+ uint32_t nxst_subtype, struct ofpbuf **bufferp)
+{
+ struct ofpbuf *msg;
+
+ msg = *bufferp = ofpbuf_new(openflow_len);
+ put_stats__(alloc_xid(), OFPT_STATS_REQUEST,
+ htons(ofpst_type), htonl(nxst_subtype), msg);
+ ofpbuf_padto(msg, openflow_len);
+
+ return msg->data;
+}
+
+static void
+put_stats_reply__(const struct ofp_stats_msg *request, struct ofpbuf *msg)
+{
+ assert(request->header.type == OFPT_STATS_REQUEST ||
+ request->header.type == OFPT_STATS_REPLY);
+ put_stats__(request->header.xid, OFPT_STATS_REPLY, request->type,
+ (request->type != htons(OFPST_VENDOR)
+ ? htonl(0)
+ : ((const struct nicira_stats_msg *) request)->subtype),
+ msg);
+}
+
+/* Creates a statistics reply message with total length 'openflow_len'
+ * (including all headers) and the same type (either a standard OpenFlow
+ * statistics type or a Nicira extension type and subtype) as 'request', and
+ * stores the buffer containing the new message in '*bufferp'.
+ *
+ * Initializes bytes following the headers to all-bits-zero.
+ *
+ * Returns the first byte of the new message. */
+void *
+ofputil_make_stats_reply(size_t openflow_len,
+ const struct ofp_stats_msg *request,
+ struct ofpbuf **bufferp)
+{
+ struct ofpbuf *msg;
+
+ msg = *bufferp = ofpbuf_new(openflow_len);
+ put_stats_reply__(request, msg);
+ ofpbuf_padto(msg, openflow_len);
+
+ return msg->data;
+}
+
+/* Initializes 'replies' as a list of ofpbufs that will contain a series of
+ * replies to 'request', which should be an OpenFlow or Nicira extension
+ * statistics request. Initially 'replies' will have a single reply message
+ * that has only a header. The functions ofputil_reserve_stats_reply() and
+ * ofputil_append_stats_reply() may be used to add to the reply. */
+void
+ofputil_start_stats_reply(const struct ofp_stats_msg *request,
+ struct list *replies)
+{
+ struct ofpbuf *msg;
+
+ msg = ofpbuf_new(1024);
+ put_stats_reply__(request, msg);
+
+ list_init(replies);
+ list_push_back(replies, &msg->list_node);
+}
+
+/* Prepares to append up to 'len' bytes to the series of statistics replies in
+ * 'replies', which should have been initialized with
+ * ofputil_start_stats_reply(). Returns an ofpbuf with at least 'len' bytes of
+ * tailroom. (The 'len' bytes have not actually be allocated; the caller must
+ * do so with e.g. ofpbuf_put_uninit().) */
+struct ofpbuf *
+ofputil_reserve_stats_reply(size_t len, struct list *replies)
+{
+ struct ofpbuf *msg = ofpbuf_from_list(list_back(replies));
+ struct ofp_stats_msg *osm = msg->data;
+
+ if (msg->size + len <= UINT16_MAX) {
+ ofpbuf_prealloc_tailroom(msg, len);
+ } else {
+ osm->flags |= htons(OFPSF_REPLY_MORE);
+
+ msg = ofpbuf_new(MAX(1024, sizeof(struct nicira_stats_msg) + len));
+ put_stats_reply__(osm, msg);
+ list_push_back(replies, &msg->list_node);
+ }
+ return msg;
+}
+
+/* Appends 'len' bytes to the series of statistics replies in 'replies', and
+ * returns the first byte. */
+void *
+ofputil_append_stats_reply(size_t len, struct list *replies)
+{
+ return ofpbuf_put_uninit(ofputil_reserve_stats_reply(len, replies), len);
+}
+
+/* Returns the first byte past the ofp_stats_msg header in 'oh'. */
+const void *
+ofputil_stats_body(const struct ofp_header *oh)
+{
+ assert(oh->type == OFPT_STATS_REQUEST || oh->type == OFPT_STATS_REPLY);
+ return (const struct ofp_stats_msg *) oh + 1;
+}
+
+/* Returns the number of bytes past the ofp_stats_msg header in 'oh'. */
+size_t
+ofputil_stats_body_len(const struct ofp_header *oh)
+{
+ assert(oh->type == OFPT_STATS_REQUEST || oh->type == OFPT_STATS_REPLY);
+ return ntohs(oh->length) - sizeof(struct ofp_stats_msg);
+}
+
+/* Returns the first byte past the nicira_stats_msg header in 'oh'. */
+const void *
+ofputil_nxstats_body(const struct ofp_header *oh)
+{
+ assert(oh->type == OFPT_STATS_REQUEST || oh->type == OFPT_STATS_REPLY);
+ return ((const struct nicira_stats_msg *) oh) + 1;
+}
+
+/* Returns the number of bytes past the nicira_stats_msg header in 'oh'. */
+size_t
+ofputil_nxstats_body_len(const struct ofp_header *oh)
+{
+ assert(oh->type == OFPT_STATS_REQUEST || oh->type == OFPT_STATS_REPLY);
+ return ntohs(oh->length) - sizeof(struct nicira_stats_msg);
+}
+
+struct ofpbuf *
+make_flow_mod(uint16_t command, const struct cls_rule *rule,
+ size_t actions_len)
+{
+ struct ofp_flow_mod *ofm;
+ size_t size = sizeof *ofm + actions_len;
+ struct ofpbuf *out = ofpbuf_new(size);
+ ofm = ofpbuf_put_zeros(out, sizeof *ofm);
+ ofm->header.version = OFP_VERSION;
+ ofm->header.type = OFPT_FLOW_MOD;
+ ofm->header.length = htons(size);
+ ofm->cookie = 0;
+ ofm->priority = htons(MIN(rule->priority, UINT16_MAX));
+ ofputil_cls_rule_to_match(rule, &ofm->match);
+ ofm->command = htons(command);
+ return out;
+}
+
+struct ofpbuf *
+make_add_flow(const struct cls_rule *rule, uint32_t buffer_id,
+ uint16_t idle_timeout, size_t actions_len)
+{
+ struct ofpbuf *out = make_flow_mod(OFPFC_ADD, rule, actions_len);
+ struct ofp_flow_mod *ofm = out->data;
+ ofm->idle_timeout = htons(idle_timeout);
+ ofm->hard_timeout = htons(OFP_FLOW_PERMANENT);