X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=include%2Fopenflow%2Fnicira-ext.h;h=6ce87a2539e0c41da3032f7272ca93a3900a3134;hb=75a75043564dc9b002fffa6c6ad71e0d4d5c892e;hp=4fab6f17c854f213425bd7dd2307f940cbf58c8e;hpb=308881afb61e292c629b36a357cfc37153884000;p=sliver-openvswitch.git diff --git a/include/openflow/nicira-ext.h b/include/openflow/nicira-ext.h index 4fab6f17c..6ce87a253 100644 --- a/include/openflow/nicira-ext.h +++ b/include/openflow/nicira-ext.h @@ -281,7 +281,8 @@ enum nx_action_subtype { NXAST_BUNDLE, /* struct nx_action_bundle */ NXAST_BUNDLE_LOAD, /* struct nx_action_bundle */ NXAST_RESUBMIT_TABLE, /* struct nx_action_resubmit */ - NXAST_OUTPUT_REG /* struct nx_action_output_reg */ + NXAST_OUTPUT_REG, /* struct nx_action_output_reg */ + NXAST_LEARN /* struct nx_action_learn */ }; /* Header for Nicira-defined actions. */ @@ -656,6 +657,219 @@ enum nx_mp_algorithm { NX_MP_ALG_ITER_HASH /* Iterative Hash. */ }; +/* Action structure for NXAST_LEARN. + * + * This action adds or modifies a flow in an OpenFlow table, similar to + * OFPT_FLOW_MOD with OFPFC_MODIFY_STRICT as 'command'. The new flow has the + * specified idle timeout, hard timeout, priority, cookie, and flags. The new + * flow's match criteria and actions are built by applying each of the series + * of flow_mod_spec elements included as part of the action. + * + * A flow_mod_spec starts with a 16-bit header. A header that is all-bits-0 is + * a no-op used for padding the action as a whole to a multiple of 8 bytes in + * length. Otherwise, the flow_mod_spec can be thought of as copying 'n_bits' + * bits from a source to a destination. In this case, the header contains + * multiple fields: + * + * 15 14 13 12 11 10 0 + * +------+---+------+---------------------------------+ + * | 0 |src| dst | n_bits | + * +------+---+------+---------------------------------+ + * + * The meaning and format of a flow_mod_spec depends on 'src' and 'dst'. The + * following table summarizes the meaning of each possible combination. + * Details follow the table: + * + * src dst meaning + * --- --- ---------------------------------------------------------- + * 0 0 Add match criteria based on value in a field. + * 1 0 Add match criteria based on an immediate value. + * 0 1 Add NXAST_REG_LOAD action to copy field into a different field. + * 1 1 Add NXAST_REG_LOAD action to load immediate value into a field. + * 0 2 Add OFPAT_OUTPUT action to output to port from specified field. + * All other combinations are undefined and not allowed. + * + * The flow_mod_spec header is followed by a source specification and a + * destination specification. The format and meaning of the source + * specification depends on 'src': + * + * - If 'src' is 0, the source bits are taken from a field in the flow to + * which this action is attached. (This should be a wildcarded field. If + * its value is fully specified then the source bits being copied have + * constant values.) + * + * The source specification is an ovs_be32 'field' and an ovs_be16 'ofs'. + * 'field' is an nxm_header with nxm_hasmask=0, and 'ofs' the starting bit + * offset within that field. The source bits are field[ofs:ofs+n_bits-1]. + * 'field' and 'ofs' are subject to the same restrictions as the source + * field in NXAST_REG_MOVE. + * + * - If 'src' is 1, the source bits are a constant value. The source + * specification is (n_bits+15)/16*2 bytes long. Taking those bytes as a + * number in network order, the source bits are the 'n_bits' + * least-significant bits. The switch will report an error if other bits + * in the constant are nonzero. + * + * The flow_mod_spec destination specification, for 'dst' of 0 or 1, is an + * ovs_be32 'field' and an ovs_be16 'ofs'. 'field' is an nxm_header with + * nxm_hasmask=0 and 'ofs' is a starting bit offset within that field. The + * meaning of the flow_mod_spec depends on 'dst': + * + * - If 'dst' is 0, the flow_mod_spec specifies match criteria for the new + * flow. The new flow matches only if bits field[ofs:ofs+n_bits-1] in a + * packet equal the source bits. 'field' may be any nxm_header with + * nxm_hasmask=0 that is allowed in NXT_FLOW_MOD. + * + * Order is significant. Earlier flow_mod_specs must satisfy any + * prerequisites for matching fields specified later, by copying constant + * values into prerequisite fields. + * + * The switch will reject flow_mod_specs that do not satisfy NXM masking + * restrictions. + * + * - If 'dst' is 1, the flow_mod_spec specifies an NXAST_REG_LOAD action for + * the new flow. The new flow copies the source bits into + * field[ofs:ofs+n_bits-1]. Actions are executed in the same order as the + * flow_mod_specs. + * + * The flow_mod_spec destination spec for 'dst' of 2 (when 'src' is 0) is + * empty. It has the following meaning: + * + * - The flow_mod_spec specifies an OFPAT_OUTPUT action for the new flow. + * The new flow outputs to the OpenFlow port specified by the source field. + * Of the special output ports with value OFPP_MAX or larger, OFPP_IN_PORT, + * OFPP_FLOOD, OFPP_LOCAL, and OFPP_ALL are supported. Other special ports + * may not be used. + * + * Resource Management + * ------------------- + * + * A switch has a finite amount of flow table space available for learning. + * When this space is exhausted, no new learning table entries will be learned + * until some existing flow table entries expire. The controller should be + * prepared to handle this by flooding (which can be implemented as a + * low-priority flow). + * + * Examples + * -------- + * + * The following examples give a prose description of the flow_mod_specs along + * with informal notation for how those would be represented and a hex dump of + * the bytes that would be required. + * + * These examples could work with various nx_action_learn parameters. Typical + * values would be idle_timeout=OFP_FLOW_PERMANENT, hard_timeout=60, + * priority=OFP_DEFAULT_PRIORITY, flags=0, table_id=10. + * + * 1. Learn input port based on the source MAC, with lookup into + * NXM_NX_REG1[16:31] by resubmit to in_port=99: + * + * Match on in_port=99: + * ovs_be16(src=1, dst=0, n_bits=16), 20 10 + * ovs_be16(99), 00 63 + * ovs_be32(NXM_OF_IN_PORT), ovs_be16(0) 00 00 00 02 00 00 + * + * Match Ethernet destination on Ethernet source from packet: + * ovs_be16(src=0, dst=0, n_bits=48), 00 30 + * ovs_be32(NXM_OF_ETH_SRC), ovs_be16(0) 00 00 04 06 00 00 + * ovs_be32(NXM_OF_ETH_DST), ovs_be16(0) 00 00 02 06 00 00 + * + * Set NXM_NX_REG1[16:31] to the packet's input port: + * ovs_be16(src=0, dst=1, n_bits=16), 08 10 + * ovs_be32(NXM_OF_IN_PORT), ovs_be16(0) 00 00 00 02 00 00 + * ovs_be32(NXM_NX_REG1), ovs_be16(16) 00 01 02 04 00 10 + * + * Given a packet that arrived on port A with Ethernet source address B, + * this would set up the flow "in_port=99, dl_dst=B, + * actions=load:A->NXM_NX_REG1[16..31]". + * + * In syntax accepted by ovs-ofctl, this action is: learn(in_port=99, + * NXM_OF_ETH_DST[]=NXM_OF_ETH_SRC[], NXM_OF_IN_PORT[]->NXM_NX_REG1[16..31]) + * + * 2. Output to input port based on the source MAC and VLAN VID, with lookup + * into NXM_NX_REG1[16:31]: + * + * Match on same VLAN ID as packet: + * ovs_be16(src=0, dst=0, n_bits=12), 00 0c + * ovs_be32(NXM_OF_VLAN_TCI), ovs_be16(0) 00 00 08 02 00 00 + * ovs_be32(NXM_OF_VLAN_TCI), ovs_be16(0) 00 00 08 02 00 00 + * + * Match Ethernet destination on Ethernet source from packet: + * ovs_be16(src=0, dst=0, n_bits=48), 00 30 + * ovs_be32(NXM_OF_ETH_SRC), ovs_be16(0) 00 00 04 06 00 00 + * ovs_be32(NXM_OF_ETH_DST), ovs_be16(0) 00 00 02 06 00 00 + * + * Output to the packet's input port: + * ovs_be16(src=0, dst=2, n_bits=16), 10 10 + * ovs_be32(NXM_OF_IN_PORT), ovs_be16(0) 00 00 00 02 00 00 + * + * Given a packet that arrived on port A with Ethernet source address B in + * VLAN C, this would set up the flow "dl_dst=B, vlan_vid=C, + * actions=output:A". + * + * In syntax accepted by ovs-ofctl, this action is: + * learn(NXM_OF_VLAN_TCI[0..11], NXM_OF_ETH_DST[]=NXM_OF_ETH_SRC[], + * output:NXM_OF_IN_PORT[]) + * + * 3. Here's a recipe for a very simple-minded MAC learning switch. It uses a + * 10-second MAC expiration time to make it easier to see what's going on + * + * ovs-vsctl del-controller br0 + * ovs-ofctl del-flows br0 + * ovs-ofctl add-flow br0 "table=0 actions=learn(table=1, \ + hard_timeout=10, NXM_OF_VLAN_TCI[0..11], \ + NXM_OF_ETH_DST[]=NXM_OF_ETH_SRC[], \ + output:NXM_OF_IN_PORT[]), resubmit(,1)" + * ovs-ofctl add-flow br0 "table=1 priority=0 actions=flood" + * + * You can then dump the MAC learning table with: + * + * ovs-ofctl dump-flows br0 table=1 + * + * Usage Advice + * ------------ + * + * For best performance, segregate learned flows into a table that is not used + * for any other flows except possibly for a lowest-priority "catch-all" flow + * (a flow with no match criteria). If different learning actions specify + * different match criteria, use different tables for the learned flows. + * + * The meaning of 'hard_timeout' and 'idle_timeout' can be counterintuitive. + * These timeouts apply to the flow that is added, which means that a flow with + * an idle timeout will expire when no traffic has been sent *to* the learned + * address. This is not usually the intent in MAC learning; instead, we want + * the MAC learn entry to expire when no traffic has been sent *from* the + * learned address. Use a hard timeout for that. + */ +struct nx_action_learn { + ovs_be16 type; /* OFPAT_VENDOR. */ + ovs_be16 len; /* At least 24. */ + ovs_be32 vendor; /* NX_VENDOR_ID. */ + ovs_be16 subtype; /* NXAST_LEARN. */ + ovs_be16 idle_timeout; /* Idle time before discarding (seconds). */ + ovs_be16 hard_timeout; /* Max time before discarding (seconds). */ + ovs_be16 priority; /* Priority level of flow entry. */ + ovs_be64 cookie; /* Cookie for new flow. */ + ovs_be16 flags; /* Either 0 or OFPFF_SEND_FLOW_REM. */ + uint8_t table_id; /* Table to insert flow entry. */ + uint8_t pad[5]; /* Must be zero. */ + /* Followed by a sequence of flow_mod_spec elements, as described above, + * until the end of the action is reached. */ +}; +OFP_ASSERT(sizeof(struct nx_action_learn) == 32); + +#define NX_LEARN_N_BITS_MASK 0x3ff + +#define NX_LEARN_SRC_FIELD (0 << 13) /* Copy from field. */ +#define NX_LEARN_SRC_IMMEDIATE (1 << 13) /* Copy from immediate value. */ +#define NX_LEARN_SRC_MASK (1 << 13) + +#define NX_LEARN_DST_MATCH (0 << 11) /* Add match criterion. */ +#define NX_LEARN_DST_LOAD (1 << 11) /* Add NXAST_REG_LOAD action. */ +#define NX_LEARN_DST_OUTPUT (2 << 11) /* Add OFPAT_OUTPUT action. */ +#define NX_LEARN_DST_RESERVED (3 << 11) /* Not yet defined. */ +#define NX_LEARN_DST_MASK (3 << 11) + /* Action structure for NXAST_AUTOPATH. * * This action performs the following steps in sequence: