vswitchd: Implement Link Aggregation Control Protocol.

This commit implements LACP, a protocol which allows directly
connected switches to automatically negotiate which links may
participate in bonds.  This commit disables LACP by default.  Once
sufficiently tested, LACP will be enabled in "active" mode on
bonded ports, and "passive" mode on all others.

Bug #4213.

1 files changed, 58 insertions, 0 deletions

diff --git a/lib/packets.h b/lib/packets.h
index 38f98fb0..0bc368b9 100644
--- a/lib/packets.h
+++ b/lib/packets.h
@@ -40,6 +40,9 @@ static const uint8_t eth_addr_broadcast[ETH_ADDR_LEN] OVS_UNUSED
 static const uint8_t eth_addr_stp[ETH_ADDR_LEN] OVS_UNUSED
     = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x01 };
 
+static const uint8_t eth_addr_lacp[ETH_ADDR_LEN] OVS_UNUSED
+    = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x02 };
+
 static inline bool eth_addr_is_broadcast(const uint8_t ea[6])
 {
     return (ea[0] & ea[1] & ea[2] & ea[3] & ea[4] & ea[5]) == 0xff;
@@ -161,6 +164,7 @@ void compose_benign_packet(struct ofpbuf *, const char *tag,
 #define ETH_TYPE_VLAN          0x8100
 #define ETH_TYPE_IPV6          0x86dd
 #define ETH_TYPE_CFM           0x8902
+#define ETH_TYPE_LACP          0x8809
 
 /* Minimum value for an Ethernet type.  Values below this are IEEE 802.2 frame
  * lengths. */
@@ -408,4 +412,58 @@ struct in6_addr ipv6_create_mask(int mask);
 int ipv6_count_cidr_bits(const struct in6_addr *netmask);
 bool ipv6_is_cidr(const struct in6_addr *netmask);
 
+/* Masks for lacp_info state member. */
+#define LACP_STATE_ACT  0x01 /* Activity. Active or passive? */
+#define LACP_STATE_TIME 0x02 /* Timeout. Short or long timeout? */
+#define LACP_STATE_AGG  0x04 /* Aggregation. Is the link is bondable? */
+#define LACP_STATE_SYNC 0x08 /* Synchronization. Is the link in up to date? */
+#define LACP_STATE_COL  0x10 /* Collecting. Is the link receiving frames? */
+#define LACP_STATE_DIST 0x20 /* Distributing. Is the link sending frames? */
+#define LACP_STATE_DEF  0x40 /* Defaulted. Using default partner info? */
+#define LACP_STATE_EXP  0x80 /* Expired. Using expired partner info? */
+
+#define LACP_FAST_TIME_TX 1000  /* Fast transmission rate. */
+#define LACP_SLOW_TIME_TX 30000 /* Slow transmission rate. */
+#define LACP_FAST_TIME_RX (LACP_FAST_TIME_TX * 3) /* Fast receive rate. */
+#define LACP_SLOW_TIME_RX (LACP_SLOW_TIME_TX * 3) /* Slow receive rate. */
+
+#define LACP_INFO_LEN 15
+struct lacp_info {
+    ovs_be16 sys_priority;       /* System priority. */
+    uint8_t sysid[ETH_ADDR_LEN]; /* System ID. */
+    ovs_be16 key;                /* Operational key. */
+    ovs_be16 port_priority;      /* Port priority. */
+    ovs_be16 portid;             /* Port ID. */
+    uint8_t state;               /* State mask.  See LACP_STATE macros. */
+} __attribute__((packed));
+BUILD_ASSERT_DECL(LACP_INFO_LEN == sizeof(struct lacp_info));
+
+#define LACP_PDU_LEN 110
+struct lacp_pdu {
+    uint8_t subtype;          /* Always 1. */
+    uint8_t version;          /* Always 1. */
+
+    uint8_t actor_type;       /* Always 1. */
+    uint8_t actor_len;        /* Always 20. */
+    struct lacp_info actor;   /* LACP actor information. */
+    uint8_t z1[3];            /* Reserved.  Always 0. */
+
+    uint8_t partner_type;     /* Always 2. */
+    uint8_t partner_len;      /* Always 20. */
+    struct lacp_info partner; /* LACP partner information. */
+    uint8_t z2[3];            /* Reserved.  Always 0. */
+
+    uint8_t collector_type;   /* Always 3. */
+    uint8_t collector_len;    /* Always 16. */
+    ovs_be16 collector_delay; /* Maximum collector delay. Set to UINT16_MAX. */
+    uint8_t z3[64];           /* Combination of several fields.  Always 0. */
+} __attribute__((packed));
+BUILD_ASSERT_DECL(LACP_PDU_LEN == sizeof(struct lacp_pdu));
+
+void compose_lacp_packet(struct ofpbuf *, struct lacp_info *actor,
+                         struct lacp_info *partner,
+                         const uint8_t eth_src[ETH_ADDR_LEN]);
+
+const struct lacp_pdu *parse_lacp_packet(const struct ofpbuf *);
+
 #endif /* packets.h */