+struct ofp_prop_header {
+ ovs_be16 type;
+ ovs_be16 len;
+};
+
+static enum ofperr
+ofputil_pull_property(struct ofpbuf *msg, struct ofpbuf *payload,
+ uint16_t *typep)
+{
+ struct ofp_prop_header *oph;
+ unsigned int len;
+
+ if (ofpbuf_size(msg) < sizeof *oph) {
+ return OFPERR_OFPTFFC_BAD_LEN;
+ }
+
+ oph = ofpbuf_data(msg);
+ len = ntohs(oph->len);
+ if (len < sizeof *oph || ROUND_UP(len, 8) > ofpbuf_size(msg)) {
+ return OFPERR_OFPTFFC_BAD_LEN;
+ }
+
+ *typep = ntohs(oph->type);
+ if (payload) {
+ ofpbuf_use_const(payload, ofpbuf_data(msg), len);
+ ofpbuf_pull(payload, sizeof *oph);
+ }
+ ofpbuf_pull(msg, ROUND_UP(len, 8));
+ return 0;
+}
+
+static void PRINTF_FORMAT(2, 3)
+log_property(bool loose, const char *message, ...)
+{
+ enum vlog_level level = loose ? VLL_DBG : VLL_WARN;
+ if (!vlog_should_drop(THIS_MODULE, level, &bad_ofmsg_rl)) {
+ va_list args;
+
+ va_start(args, message);
+ vlog_valist(THIS_MODULE, level, message, args);
+ va_end(args);
+ }
+}
+
+static enum ofperr
+parse_table_ids(struct ofpbuf *payload, uint32_t *ids)
+{
+ uint16_t type;
+
+ *ids = 0;
+ while (ofpbuf_size(payload) > 0) {
+ enum ofperr error = ofputil_pull_property(payload, NULL, &type);
+ if (error) {
+ return error;
+ }
+ if (type < CHAR_BIT * sizeof *ids) {
+ *ids |= 1u << type;
+ }
+ }
+ return 0;
+}
+
+static enum ofperr
+parse_instruction_ids(struct ofpbuf *payload, bool loose, uint32_t *insts)
+{
+ *insts = 0;
+ while (ofpbuf_size(payload) > 0) {
+ enum ovs_instruction_type inst;
+ enum ofperr error;
+ uint16_t ofpit;
+
+ error = ofputil_pull_property(payload, NULL, &ofpit);
+ if (error) {
+ return error;
+ }
+
+ error = ovs_instruction_type_from_inst_type(&inst, ofpit);
+ if (!error) {
+ *insts |= 1u << inst;
+ } else if (!loose) {
+ return error;
+ }
+ }
+ return 0;
+}
+
+static enum ofperr
+parse_table_features_next_table(struct ofpbuf *payload,
+ unsigned long int *next_tables)
+{
+ size_t i;
+
+ memset(next_tables, 0, bitmap_n_bytes(255));
+ for (i = 0; i < ofpbuf_size(payload); i++) {
+ uint8_t id = ((const uint8_t *) ofpbuf_data(payload))[i];
+ if (id >= 255) {
+ return OFPERR_OFPTFFC_BAD_ARGUMENT;
+ }
+ bitmap_set1(next_tables, id);
+ }
+ return 0;
+}
+
+static enum ofperr
+parse_oxm(struct ofpbuf *b, bool loose,
+ const struct mf_field **fieldp, bool *hasmask)
+{
+ ovs_be32 *oxmp;
+ uint32_t oxm;
+
+ oxmp = ofpbuf_try_pull(b, sizeof *oxmp);
+ if (!oxmp) {
+ return OFPERR_OFPTFFC_BAD_LEN;
+ }
+ oxm = ntohl(*oxmp);
+
+ /* Determine '*hasmask'. If 'oxm' is masked, convert it to the equivalent
+ * unmasked version, because the table of OXM fields we support only has
+ * masked versions of fields that we support with masks, but we should be
+ * able to parse the masked versions of those here. */
+ *hasmask = NXM_HASMASK(oxm);
+ if (*hasmask) {
+ if (NXM_LENGTH(oxm) & 1) {
+ return OFPERR_OFPTFFC_BAD_ARGUMENT;
+ }
+ oxm = NXM_HEADER(NXM_VENDOR(oxm), NXM_FIELD(oxm), NXM_LENGTH(oxm) / 2);
+ }
+
+ *fieldp = mf_from_nxm_header(oxm);
+ if (!*fieldp) {
+ log_property(loose, "unknown OXM field %#"PRIx32, ntohl(*oxmp));
+ }
+ return *fieldp ? 0 : OFPERR_OFPBMC_BAD_FIELD;
+}
+
+static enum ofperr
+parse_oxms(struct ofpbuf *payload, bool loose,
+ uint64_t *exactp, uint64_t *maskedp)
+{
+ uint64_t exact, masked;
+
+ exact = masked = 0;
+ while (ofpbuf_size(payload) > 0) {
+ const struct mf_field *field;
+ enum ofperr error;
+ bool hasmask;
+
+ error = parse_oxm(payload, loose, &field, &hasmask);
+ if (!error) {
+ if (hasmask) {
+ masked |= UINT64_C(1) << field->id;
+ } else {
+ exact |= UINT64_C(1) << field->id;
+ }
+ } else if (error != OFPERR_OFPBMC_BAD_FIELD || !loose) {
+ return error;
+ }
+ }
+ if (exactp) {
+ *exactp = exact;
+ } else if (exact) {
+ return OFPERR_OFPBMC_BAD_MASK;
+ }
+ if (maskedp) {
+ *maskedp = masked;
+ } else if (masked) {
+ return OFPERR_OFPBMC_BAD_MASK;
+ }
+ return 0;
+}
+
+/* Converts an OFPMP_TABLE_FEATURES request or reply in 'msg' into an abstract
+ * ofputil_table_features in 'tf'.
+ *
+ * If 'loose' is true, this function ignores properties and values that it does
+ * not understand, as a controller would want to do when interpreting
+ * capabilities provided by a switch. If 'loose' is false, this function
+ * treats unknown properties and values as an error, as a switch would want to
+ * do when interpreting a configuration request made by a controller.
+ *
+ * A single OpenFlow message can specify features for multiple tables. Calling
+ * this function multiple times for a single 'msg' iterates through the tables
+ * in the message. The caller must initially leave 'msg''s layer pointers null
+ * and not modify them between calls.
+ *
+ * Returns 0 if successful, EOF if no tables were left in this 'msg', otherwise
+ * a positive "enum ofperr" value. */
+int
+ofputil_decode_table_features(struct ofpbuf *msg,
+ struct ofputil_table_features *tf, bool loose)
+{
+ struct ofp13_table_features *otf;
+ unsigned int len;
+
+ if (!msg->frame) {
+ ofpraw_pull_assert(msg);
+ }
+
+ if (!ofpbuf_size(msg)) {
+ return EOF;
+ }
+
+ if (ofpbuf_size(msg) < sizeof *otf) {
+ return OFPERR_OFPTFFC_BAD_LEN;
+ }
+
+ otf = ofpbuf_data(msg);
+ len = ntohs(otf->length);
+ if (len < sizeof *otf || len % 8 || len > ofpbuf_size(msg)) {
+ return OFPERR_OFPTFFC_BAD_LEN;
+ }
+ ofpbuf_pull(msg, sizeof *otf);
+
+ tf->table_id = otf->table_id;
+ if (tf->table_id == OFPTT_ALL) {
+ return OFPERR_OFPTFFC_BAD_TABLE;
+ }
+
+ ovs_strlcpy(tf->name, otf->name, OFP_MAX_TABLE_NAME_LEN);
+ tf->metadata_match = otf->metadata_match;
+ tf->metadata_write = otf->metadata_write;
+ tf->config = ntohl(otf->config);
+ tf->max_entries = ntohl(otf->max_entries);
+
+ while (ofpbuf_size(msg) > 0) {
+ struct ofpbuf payload;
+ enum ofperr error;
+ uint16_t type;
+
+ error = ofputil_pull_property(msg, &payload, &type);
+ if (error) {
+ return error;
+ }
+
+ switch ((enum ofp13_table_feature_prop_type) type) {
+ case OFPTFPT13_INSTRUCTIONS:
+ error = parse_instruction_ids(&payload, loose,
+ &tf->nonmiss.instructions);
+ break;
+ case OFPTFPT13_INSTRUCTIONS_MISS:
+ error = parse_instruction_ids(&payload, loose,
+ &tf->miss.instructions);
+ break;
+
+ case OFPTFPT13_NEXT_TABLES:
+ error = parse_table_features_next_table(&payload,
+ tf->nonmiss.next);
+ break;
+ case OFPTFPT13_NEXT_TABLES_MISS:
+ error = parse_table_features_next_table(&payload, tf->miss.next);
+ break;
+
+ case OFPTFPT13_WRITE_ACTIONS:
+ error = parse_table_ids(&payload, &tf->nonmiss.write.actions);
+ break;
+ case OFPTFPT13_WRITE_ACTIONS_MISS:
+ error = parse_table_ids(&payload, &tf->miss.write.actions);
+ break;
+
+ case OFPTFPT13_APPLY_ACTIONS:
+ error = parse_table_ids(&payload, &tf->nonmiss.apply.actions);
+ break;
+ case OFPTFPT13_APPLY_ACTIONS_MISS:
+ error = parse_table_ids(&payload, &tf->miss.apply.actions);
+ break;
+
+ case OFPTFPT13_MATCH:
+ error = parse_oxms(&payload, loose, &tf->match, &tf->mask);
+ break;
+ case OFPTFPT13_WILDCARDS:
+ error = parse_oxms(&payload, loose, &tf->wildcard, NULL);
+ break;
+
+ case OFPTFPT13_WRITE_SETFIELD:
+ error = parse_oxms(&payload, loose,
+ &tf->nonmiss.write.set_fields, NULL);
+ break;
+ case OFPTFPT13_WRITE_SETFIELD_MISS:
+ error = parse_oxms(&payload, loose,
+ &tf->miss.write.set_fields, NULL);
+ break;
+ case OFPTFPT13_APPLY_SETFIELD:
+ error = parse_oxms(&payload, loose,
+ &tf->nonmiss.apply.set_fields, NULL);
+ break;
+ case OFPTFPT13_APPLY_SETFIELD_MISS:
+ error = parse_oxms(&payload, loose,
+ &tf->miss.apply.set_fields, NULL);
+ break;
+
+ case OFPTFPT13_EXPERIMENTER:
+ case OFPTFPT13_EXPERIMENTER_MISS:
+ log_property(loose,
+ "unknown table features experimenter property");
+ error = loose ? 0 : OFPERR_OFPTFFC_BAD_TYPE;
+ break;
+ }
+ if (error) {
+ return error;
+ }
+ }
+
+ /* Fix inconsistencies:
+ *
+ * - Turn off 'mask' and 'wildcard' bits that are not in 'match',
+ * because a field must be matchable to be masked or wildcarded.
+ *
+ * - Turn on 'wildcard' bits that are set in 'mask', because a field
+ * that is arbitrarily maskable can be wildcarded entirely. */
+ tf->mask &= tf->match;
+ tf->wildcard &= tf->match;
+
+ tf->wildcard |= tf->mask;
+
+ return 0;
+}
+
+/* Encodes and returns a request to obtain the table features of a switch.
+ * The message is encoded for OpenFlow version 'ofp_version'. */
+struct ofpbuf *
+ofputil_encode_table_features_request(enum ofp_version ofp_version)
+{
+ struct ofpbuf *request = NULL;
+
+ switch (ofp_version) {
+ case OFP10_VERSION:
+ case OFP11_VERSION:
+ case OFP12_VERSION:
+ ovs_fatal(0, "dump-table-features needs OpenFlow 1.3 or later "
+ "(\'-O OpenFlow13\')");
+ case OFP13_VERSION:
+ case OFP14_VERSION:
+ request = ofpraw_alloc(OFPRAW_OFPST13_TABLE_FEATURES_REQUEST,
+ ofp_version, 0);
+ break;
+ default:
+ OVS_NOT_REACHED();
+ }
+
+ return request;
+}
+