+/* Converts an OFPST_FLOW or NXST_FLOW reply in 'msg' into an abstract
+ * ofputil_flow_stats in 'fs'. For OFPST_FLOW messages, 'flow_format' should
+ * be the current flow format at the time when the request corresponding to the
+ * reply in 'msg' was sent. Otherwise 'flow_format' is ignored.
+ *
+ * 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,
+ enum nx_flow_format flow_format)
+{
+ 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_reply));
+ } 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),
+ flow_format, fs->cookie, &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;
+}
+