[lacp] Add simple LACP implementation

Some switch configurations will refuse to enable our port unless we
can speak LACP to inform the switch that we are alive.  Add a very
simple passive LACP implementation that is sufficient to convince at
least Linux's bonding driver (when tested using qemu attached to a tap
device enslaved to a bond device configured as "mode=802.3ad").

Signed-off-by: Michael Brown <mcb30@ipxe.org>

src/core/proto_eth_slow.c

@@ -1,406 +0,0 @@
-/* Copyright 2004 Linux Networx */
-#ifdef PROTO_LACP
-#if 0
-#include "nic.h"
-#include "timer.h"
-#endif
-
-#define LACP_DEBUG 0
-
-/* Structure definitions originally taken from the linux bond_3ad driver */
-
-#define SLOW_DST_MAC "\x01\x80\xc2\x00\x00\x02"
-static const char slow_dest[] = SLOW_DST_MAC;
-
-
-#define SLOW_SUBTYPE_LACP 1
-#define SLOW_SUBTYPE_MARKER 2
-
-struct slow_header {
-	uint8_t subtype;
-};
-
-struct lacp_info {
-	uint16_t system_priority;
-	uint8_t  system[ETH_ALEN];
-	uint16_t key;
-	uint16_t port_priority;
-	uint16_t port;
-	uint8_t  state;
-	uint8_t  reserved[3];
-} PACKED;
-
-#define LACP_CMP_LEN (2 + 6 + 2 + 2 + 2)
-#define LACP_CP_LEN  (2 + 6 + 2 + 2 + 2 + 1)
-
-/* Link Aggregation Control Protocol(LACP) data unit structure(43.4.2.2 in the 802.3ad standard) */
-struct slow_lacp {
-	uint8_t  subtype;		       /* = LACP(= 0x01) */
-	uint8_t  version_number;
-	uint8_t  tlv_type_actor_info;	       /* = actor information(type/length/value) */
-#define LACP_TLV_TERMINATOR 0
-#define LACP_TLV_ACTOR      1
-#define LACP_TLV_PARTNER    2
-#define LACP_TLV_COLLECTOR  3
-	uint8_t  actor_information_length;     /* = 20 */
-	struct lacp_info actor;
-	uint8_t  tlv_type_partner_info;        /* = partner information */
-	uint8_t  partner_information_length;   /* = 20 */
-	struct lacp_info partner;
-	uint8_t  tlv_type_collector_info;      /* = collector information */
-	uint8_t  collector_information_length; /* = 16 */
-	uint16_t collector_max_delay;
-	uint8_t  reserved_12[12];
-	uint8_t  tlv_type_terminator;	       /* = terminator */
-	uint8_t  terminator_length;	       /* = 0 */ 
-	uint8_t  reserved_50[50];	       /* = 0 */
-} PACKED;
-
-/* Marker Protocol Data Unit(PDU) structure(43.5.3.2 in the 802.3ad standard) */
-struct slow_marker {
-	uint8_t  subtype;                      /* = 0x02  (marker PDU) */
-	uint8_t  version_number;	       /* = 0x01 */
-	uint8_t  tlv_type;
-#define MARKER_TLV_TERMINATOR 0                /* marker terminator */
-#define MARKER_TLV_INFO       1	               /* marker information */
-#define MARKER_TLV_RESPONSE   2	               /* marker response information */
-	uint8_t  marker_length;                /* = 0x16 */
-	uint16_t requester_port;	       /* The number assigned to the port by the requester */
-	uint8_t  requester_system[ETH_ALEN];   /* The requester's system id */
-	uint32_t requester_transaction_id;     /* The transaction id allocated by the requester, */
-	uint16_t pad;		               /* = 0 */
-	uint8_t  tlv_type_terminator;	       /* = 0x00 */
-	uint8_t  terminator_length;	       /* = 0x00 */
-	uint8_t  reserved_90[90];	       /* = 0 */
-} PACKED;
-
-union slow_union {
-	struct slow_header header;
-	struct slow_lacp lacp;
-	struct slow_marker marker;
-};
-
-#define FAST_PERIODIC_TIME   (1*TICKS_PER_SEC)
-#define SLOW_PERIODIC_TIME   (30*TICKS_PER_SEC)
-#define SHORT_TIMEOUT_TIME   (3*FAST_PERIODIC_TIME)
-#define LONG_TIMEOUT_TIME    (3*SLOW_PERIODIC_TIME)
-#define CHURN_DETECTION_TIME (60*TICKS_PER_SEC)
-#define AGGREGATE_WAIT_TIME  (2*TICKS_PER_SEC)
-
-#define LACP_ACTIVITY        (1 << 0)
-#define LACP_TIMEOUT         (1 << 1)
-#define LACP_AGGREGATION     (1 << 2)
-#define LACP_SYNCHRONIZATION (1 << 3)
-#define LACP_COLLECTING      (1 << 4)
-#define LACP_DISTRIBUTING    (1 << 5)
-#define LACP_DEFAULTED       (1 << 6)
-#define LACP_EXPIRED         (1 << 7)
-
-#define UNSELECTED 0
-#define STANDBY    1
-#define SELECTED   2
-
-
-struct lacp_state {
-	struct slow_lacp pkt;
-	unsigned long current_while_timer; /* Time when the LACP information expires */
-	unsigned long periodic_timer; /* Time when I need to send my partner an update */
-};
-
-static struct lacp_state lacp;
-
-
-#if LACP_DEBUG > 0
-static void print_lacp_state(uint8_t state)
-{
-	printf("%hhx", state);
-	if (state & LACP_ACTIVITY) {
-		printf(" Activity");
-	}
-	if (state & LACP_TIMEOUT) {
-		printf(" Timeout");
-	}
-	if (state & LACP_AGGREGATION) {
-		printf(" Aggregation");
-	}
-	if (state & LACP_SYNCHRONIZATION) {
-		printf(" Syncronization");
-	}
-	if (state & LACP_COLLECTING) {
-		printf(" Collecting");
-	}
-	if (state & LACP_DISTRIBUTING) {
-		printf(" Distributing");
-	}
-	if (state & LACP_DEFAULTED) {
-		printf(" Defaulted");
-	}
-	if (state & LACP_EXPIRED) {
-		printf(" Expired");
-	}
-	printf("\n");
-}
-
-static inline void print_lacpdu(struct slow_lacp *pkt)
-{
-	printf("subtype version:  %hhx %hhx\n", 
-		pkt->subtype, pkt->version_number);
-	printf("actor_tlv %hhx", pkt->tlv_type_actor_info);
-	printf(" len: %hhx (\n", pkt->actor_information_length);
-	printf(" sys_pri: %hx", ntohs(pkt->actor.system_priority));
-	printf(" mac: %!", pkt->actor.system);
-	printf(" key: %hx", ntohs(pkt->actor.key));
-	printf(" port_pri: %hx", ntohs(pkt->actor.port_priority));
-	printf(" port: %hx\n", ntohs(pkt->actor.port));
-	printf(" state: ");
-	print_lacp_state(pkt->actor.state);
-#if LACP_DEBUG > 1
-	printf(" reserved:     %hhx %hhx %hhx\n",
-		pkt->actor.reserved[0], pkt->actor.reserved[1], pkt->actor.reserved[2]);
-#endif
-	printf(")\n");
-	printf("partner_tlv: %hhx", pkt->tlv_type_partner_info);
-	printf(" len: %hhx (\n", pkt->partner_information_length);
-	printf(" sys_pri: %hx", ntohs(pkt->partner.system_priority));
-	printf(" mac: %!", pkt->partner.system);
-	printf(" key: %hx", ntohs(pkt->partner.key));
-	printf(" port_pri: %hx", ntohs(pkt->partner.port_priority));
-	printf(" port: %hx\n", ntohs(pkt->partner.port));
-	printf(" state: ");
-	print_lacp_state(pkt->partner.state);
-#if LACP_DEBUG > 1
-	printf(" reserved:     %hhx %hhx %hhx\n",
-		pkt->partner.reserved[0], pkt->partner.reserved[1], pkt->partner.reserved[2]);
-#endif
-	printf(")\n");
-	printf("collector_tlv: %hhx ", pkt->tlv_type_collector_info);
-	printf(" len: %hhx (", pkt->collector_information_length);
-	printf(" max_delay: %hx", ntohs(pkt->collector_max_delay));
-#if LACP_DEBUG > 1
-	printf("reserved_12:      %hhx %hhx %hhx %hhx %hhx %hhx %hhx %hhx %hhx %hhx %hhx %hhx\n",
-		pkt->reserved_12[0], pkt->reserved_12[1], pkt->reserved_12[2], 
-		pkt->reserved_12[3], pkt->reserved_12[4], pkt->reserved_12[5], 
-		pkt->reserved_12[6], pkt->reserved_12[7], pkt->reserved_12[8], 
-		pkt->reserved_12[9], pkt->reserved_12[10], pkt->reserved_12[11]);
-#endif
-	printf(" )\n");
-	printf("terminator_tlv: %hhx", pkt->tlv_type_terminator);
-	printf(" len: %hhx ()\n", pkt->terminator_length);
-}
-
-static inline unsigned long lacp_timer_val(unsigned long now, unsigned long when)
-{
-	return when?(when - now)/TICKS_PER_SEC : 0;
-}
-static void print_lacp(const char *which, struct slow_lacp *pkt, unsigned long now)
-{
-	printf("%s\n", which);
-	print_lacpdu(pkt);
-	printf("timers: c %ds p %ds\n",
-		lacp_timer_val(now, lacp.current_while_timer),
-		lacp_timer_val(now, lacp.periodic_timer)
-		);
-	printf("\n");
-}
-#else /* LACP_DEBUG */
-#define print_lacp(which, pkt, now) do {} while(0)
-#endif /* LACP_DEBUG */
-
-static void lacp_init_state(const uint8_t *mac)
-{
-	memset(&lacp, 0, sizeof(lacp));
-
-	/* Initialize the packet constants */
-	lacp.pkt.subtype               = 1;
-	lacp.pkt.version_number        = 1;
-
-
-	/* The default state of my interface */
-	lacp.pkt.tlv_type_actor_info      = LACP_TLV_ACTOR;
-	lacp.pkt.actor_information_length = 0x14;
-	lacp.pkt.actor.system_priority    = htons(1);
-	memcpy(lacp.pkt.actor.system, mac, ETH_ALEN);
-	lacp.pkt.actor.key                = htons(1);
-	lacp.pkt.actor.port               = htons(1);
-	lacp.pkt.actor.port_priority      = htons(1);
-	lacp.pkt.actor.state = 
-		LACP_SYNCHRONIZATION |
-		LACP_COLLECTING      |
-		LACP_DISTRIBUTING    |
-		LACP_DEFAULTED;
-
-	/* Set my partner defaults */
-	lacp.pkt.tlv_type_partner_info      = LACP_TLV_PARTNER;
-	lacp.pkt.partner_information_length = 0x14;
-	lacp.pkt.partner.system_priority    = htons(1);
-	/* memset(lacp.pkt.parnter_system, 0, ETH_ALEN); */
-	lacp.pkt.partner.key                = htons(1);
-	lacp.pkt.partner.port               = htons(1);
-	lacp.pkt.partner.port_priority      = htons(1);
-	lacp.pkt.partner.state =
-		LACP_ACTIVITY        |
-		LACP_SYNCHRONIZATION |
-		LACP_COLLECTING      |
-		LACP_DISTRIBUTING    |
-		LACP_DEFAULTED;
-
-	lacp.pkt.tlv_type_collector_info      = LACP_TLV_COLLECTOR;
-	lacp.pkt.collector_information_length = 0x10;
-	lacp.pkt.collector_max_delay          = htons(0x8000); /* ???? */
-
-	lacp.pkt.tlv_type_terminator          = LACP_TLV_TERMINATOR;
-	lacp.pkt.terminator_length            = 0;
-}
-
-#define LACP_NTT_MASK (LACP_ACTIVITY | LACP_TIMEOUT | \
-	LACP_SYNCHRONIZATION | LACP_AGGREGATION)
-
-static inline int lacp_update_ntt(struct slow_lacp *pkt)
-{
-	int ntt = 0;
-	if ((memcmp(&pkt->partner, &lacp.pkt.actor, LACP_CMP_LEN) != 0) ||
-		((pkt->partner.state & LACP_NTT_MASK) != 
-			(lacp.pkt.actor.state & LACP_NTT_MASK)))
-	{
-		ntt = 1;
-	}
-	return ntt;
-}
-
-static inline void lacp_record_pdu(struct slow_lacp *pkt)
-{
-	memcpy(&lacp.pkt.partner, &pkt->actor, LACP_CP_LEN);
-
-	lacp.pkt.actor.state &= ~LACP_DEFAULTED;
-	lacp.pkt.partner.state &= ~LACP_SYNCHRONIZATION;
-	if ((memcmp(&pkt->partner, &lacp.pkt.actor, LACP_CMP_LEN) == 0) &&
-		((pkt->partner.state & LACP_AGGREGATION) ==
-			(lacp.pkt.actor.state & LACP_AGGREGATION)))
-	{
-		lacp.pkt.partner.state  |= LACP_SYNCHRONIZATION;
-	}
-	if (!(pkt->actor.state & LACP_AGGREGATION)) {
-		lacp.pkt.partner.state |= LACP_SYNCHRONIZATION;
-	}
-
-	/* ACTIVITY? */
-}
-
-static inline int lacp_timer_expired(unsigned long now, unsigned long when)
-{
-	return when && (now > when);
-}
-
-static inline void lacp_start_periodic_timer(unsigned long now)
-{
-	if ((lacp.pkt.partner.state & LACP_ACTIVITY) ||
-		(lacp.pkt.actor.state & LACP_ACTIVITY)) {
-		lacp.periodic_timer = now +
-			(((lacp.pkt.partner.state & LACP_TIMEOUT)?
-				FAST_PERIODIC_TIME : SLOW_PERIODIC_TIME));
-	}
-}
-
-static inline void lacp_start_current_while_timer(unsigned long now)
-{
-	lacp.current_while_timer = now +
-		((lacp.pkt.actor.state & LACP_TIMEOUT) ?
-		SHORT_TIMEOUT_TIME : LONG_TIMEOUT_TIME);
-
-	lacp.pkt.actor.state &= ~LACP_EXPIRED;
-}
-
-static void send_lacp_reports(unsigned long now, int ntt)
-{
-	if (memcmp(nic.node_addr, lacp.pkt.actor.system, ETH_ALEN) != 0) {
-		lacp_init_state(nic.node_addr);
-	}
-	/* If the remote information has expired I need to take action */
-	if (lacp_timer_expired(now, lacp.current_while_timer)) {
-		if (!(lacp.pkt.actor.state & LACP_EXPIRED)) {
-			lacp.pkt.partner.state &= ~LACP_SYNCHRONIZATION;
-			lacp.pkt.partner.state |= LACP_TIMEOUT;
-			lacp.pkt.actor.state |= LACP_EXPIRED;
-			lacp.current_while_timer = now + SHORT_TIMEOUT_TIME;
-			ntt = 1;
-		}
-		else {
-			lacp_init_state(nic.node_addr);
-		}
-	}
-	/* If the periodic timer has expired I need to transmit */
-	if (lacp_timer_expired(now, lacp.periodic_timer)) {
-		ntt = 1;
-		/* Reset by lacp_start_periodic_timer */
-	}
-	if (ntt) {
-		eth_transmit(slow_dest, ETH_P_SLOW, sizeof(lacp.pkt), &lacp.pkt);
-
-		/* Restart the periodic timer */
-		lacp_start_periodic_timer(now);
-
-		print_lacp("Trasmitted", &lacp.pkt, now);
-	}
-}
-
-static inline void send_eth_slow_reports(unsigned long now)
-{
-	send_lacp_reports(now, 0);
-}
-
-static inline void process_eth_slow(unsigned short ptype, unsigned long now)
-{
-	union slow_union *pkt;
-	if ((ptype != ETH_P_SLOW) || 
-		(nic.packetlen < (ETH_HLEN + sizeof(pkt->header)))) {
-		return;
-	}
-	pkt = (union slow_union *)&nic.packet[ETH_HLEN];
-	if ((pkt->header.subtype == SLOW_SUBTYPE_LACP) &&
-		(nic.packetlen >= ETH_HLEN + sizeof(pkt->lacp))) {
-		int ntt;
-		if (memcmp(nic.node_addr, lacp.pkt.actor.system, ETH_ALEN) != 0) {
-			lacp_init_state(nic.node_addr);
-		}
-		/* As long as nic.packet is 2 byte aligned all is good */
-		print_lacp("Received", &pkt->lacp, now);
-		/* I don't actually implement the MUX or SELECT
-		 * machines.  
-		 *
-		 * What logically happens when the client and I
-		 * disagree about an aggregator is the current
-		 * aggregtator is unselected.  The MUX machine places
-		 * me in DETACHED.  The SELECT machine runs and
-		 * reslects the same aggregator.  If I go through
-		 * these steps fast enough an outside observer can not
-		 * notice this.  
-		 *
-		 * Since the process will not generate any noticeable
-		 * effect it does not need an implmenetation.  This
-		 * keeps the code simple and the code and binary
-		 * size down.
-		 */
-		/* lacp_update_selected(&pkt->lacp); */
-		ntt = lacp_update_ntt(&pkt->lacp);
-		lacp_record_pdu(&pkt->lacp);
-		lacp_start_current_while_timer(now);
-		send_lacp_reports(now, ntt);
-	}
-	/* If we receive a marker information packet return it */
-	else if ((pkt->header.subtype == SLOW_SUBTYPE_MARKER) &&
-		(nic.packetlen >= ETH_HLEN + sizeof(pkt->marker)) &&
-		(pkt->marker.tlv_type == MARKER_TLV_INFO) &&
-		(pkt->marker.marker_length == 0x16)) 
-	{
-		pkt->marker.tlv_type = MARKER_TLV_RESPONSE;
-		eth_transmit(slow_dest, ETH_P_SLOW, 
-			sizeof(pkt->marker), &pkt->marker);
-	}
-
- }
-#else
-
-#define send_eth_slow_reports(now)    do {} while(0)
-#define process_eth_slow(ptype, now)  do {} while(0)
-
-#endif 

src/include/ipxe/errfile.h

@@ -171,6 +171,7 @@ FILE_LICENCE ( GPL2_OR_LATER );
 #define ERRFILE_wpa_psk			( ERRFILE_NET | 0x00270000 )
 #define ERRFILE_wpa_tkip		( ERRFILE_NET | 0x00280000 )
 #define ERRFILE_wpa_ccmp		( ERRFILE_NET | 0x00290000 )
+#define ERRFILE_eth_slow		( ERRFILE_NET | 0x002a0000 )
 
 #define ERRFILE_image		      ( ERRFILE_IMAGE | 0x00000000 )
 #define ERRFILE_elf		      ( ERRFILE_IMAGE | 0x00010000 )

src/include/ipxe/eth_slow.h

@@ -0,0 +1,255 @@
+#ifndef _IPXE_ETH_SLOW_H
+#define _IPXE_ETH_SLOW_H
+
+/** @file
+ *
+ * Ethernet slow protocols
+ *
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+/** Slow protocols header */
+struct eth_slow_header {
+	/** Slow protocols subtype */
+	uint8_t subtype;
+	/** Subtype version number */
+	uint8_t version;
+} __attribute__ (( packed ));
+
+/** LACP subtype */
+#define ETH_SLOW_SUBTYPE_LACP 1
+
+/** LACP version number */
+#define ETH_SLOW_LACP_VERSION 1
+
+/** Marker subtype */
+#define ETH_SLOW_SUBTYPE_MARKER 2
+
+/** Marker version number */
+#define ETH_SLOW_MARKER_VERSION 1
+
+/** TLV (type, length, value) header */
+struct eth_slow_tlv_header {
+	/** Type
+	 *
+	 * This is an ETH_SLOW_TLV_XXX constant.
+	 */
+	uint8_t type;
+	/** Length
+	 *
+	 * The length includes the TLV header (except for a TLV
+	 * terminator, which has a length of zero).
+	 */
+	uint8_t length;
+} __attribute__ (( packed ));
+
+/** Terminator type */
+#define ETH_SLOW_TLV_TERMINATOR 0
+
+/** Terminator length */
+#define ETH_SLOW_TLV_TERMINATOR_LEN 0
+
+/** LACP actor type */
+#define ETH_SLOW_TLV_LACP_ACTOR 1
+
+/** LACP actor length */
+#define ETH_SLOW_TLV_LACP_ACTOR_LEN \
+	( sizeof ( struct eth_slow_lacp_entity_tlv ) )
+
+/** LACP partner type */
+#define ETH_SLOW_TLV_LACP_PARTNER 2
+
+/** LACP partner length */
+#define ETH_SLOW_TLV_LACP_PARTNER_LEN \
+	( sizeof ( struct eth_slow_lacp_entity_tlv ) )
+
+/** LACP collector type */
+#define ETH_SLOW_TLV_LACP_COLLECTOR 3
+
+/** LACP collector length */
+#define ETH_SLOW_TLV_LACP_COLLECTOR_LEN \
+	( sizeof ( struct eth_slow_lacp_collector_tlv ) )
+
+/** Marker request type */
+#define ETH_SLOW_TLV_MARKER_REQUEST 1
+
+/** Marker request length */
+#define ETH_SLOW_TLV_MARKER_REQUEST_LEN \
+	( sizeof ( struct eth_slow_marker_tlv ) )
+
+/** Marker response type */
+#define ETH_SLOW_TLV_MARKER_RESPONSE 2
+
+/** Marker response length */
+#define ETH_SLOW_TLV_MARKER_RESPONSE_LEN \
+	( sizeof ( struct eth_slow_marker_tlv ) )
+
+/** Terminator TLV */
+struct eth_slow_terminator_tlv {
+	/** TLV header */
+	struct eth_slow_tlv_header tlv;
+} __attribute__ (( packed ));
+
+/** LACP entity (actor or partner) TLV */
+struct eth_slow_lacp_entity_tlv {
+	/** TLV header */
+	struct eth_slow_tlv_header tlv;
+	/** System priority
+	 *
+	 * Used to determine the order in which ports are selected for
+	 * aggregation.
+	 */
+	uint16_t system_priority;
+	/** System identifier
+	 *
+	 * Used to uniquely identify the system (i.e. the entity with
+	 * potentially multiple ports).
+	 */
+	uint8_t system[ETH_ALEN];
+	/** Key
+	 *
+	 * Used to uniquely identify a group of aggregatable ports
+	 * within a system.
+	 */
+	uint16_t key;
+	/** Port priority
+	 *
+	 * Used to determine the order in which ports are selected for
+	 * aggregation.
+	 */
+	uint16_t port_priority;
+	/** Port identifier
+	 *
+	 * Used to uniquely identify a port within a system.
+	 */
+	uint16_t port;
+	/** State
+	 *
+	 * This is the bitwise OR of zero or more LACP_STATE_XXX
+	 * constants.
+	 */
+	uint8_t state;
+	/** Reserved */
+	uint8_t reserved[3];
+} __attribute__ (( packed ));
+
+/** Maximum system priority */
+#define LACP_SYSTEM_PRIORITY_MAX 0xffff
+
+/** Maximum port priority */
+#define LACP_PORT_PRIORITY_MAX 0xff
+
+/** LACP entity is active
+ *
+ * Represented by the state character "A"/"a"
+ */
+#define LACP_STATE_ACTIVE 0x01
+
+/** LACP timeout is short
+ *
+ * Short timeout is one second, long timeout is 30s
+ *
+ * Represented by the state character "F"/"f"
+ */
+#define LACP_STATE_FAST 0x02
+
+/** LACP link is aggregateable
+ *
+ * Represented by the state characters "G"/"g"
+ */
+#define LACP_STATE_AGGREGATABLE 0x04
+
+/** LACP link is in synchronisation
+ *
+ * Represented by the state characters "S"/"s"
+ */
+#define LACP_STATE_IN_SYNC 0x08
+
+/** LACP link is collecting (receiving)
+ *
+ * Represented by the state characters "C"/"c"
+ */
+#define LACP_STATE_COLLECTING 0x10
+
+/** LACP link is distributing (transmitting)
+ *
+ * Represented by the state characters "D"/"d"
+ */
+#define LACP_STATE_DISTRIBUTING 0x20
+
+/** LACP entity is using defaulted partner information
+ *
+ * Represented by the state characters "L"/"l"
+ */
+#define LACP_STATE_DEFAULTED 0x40
+
+/** LACP entity receive state machine is in EXPIRED
+ *
+ * Represented by the state characters "X"/"x"
+ */
+#define LACP_STATE_EXPIRED 0x80
+
+/** LACP collector TLV */
+struct eth_slow_lacp_collector_tlv {
+	/** TLV header */
+	struct eth_slow_tlv_header tlv;
+	/** Maximum delay (in 10us increments) */
+	uint16_t max_delay;
+	/** Reserved */
+	uint8_t reserved[12];
+} __attribute__ (( packed ));
+
+/** Marker TLV */
+struct eth_slow_marker_tlv {
+	/** TLV header */
+	struct eth_slow_tlv_header tlv;
+	/** Requester port */
+	uint16_t port;
+	/** Requester system */
+	uint8_t system[ETH_ALEN];
+	/** Requester transaction ID */
+	uint32_t xact;
+	/** Padding */
+	uint16_t pad;
+} __attribute__ (( packed ));
+
+/** LACP packet */
+struct eth_slow_lacp {
+	/** Slow protocols header */
+	struct eth_slow_header header;
+	/** Actor information */
+	struct eth_slow_lacp_entity_tlv actor;
+	/** Partner information */
+	struct eth_slow_lacp_entity_tlv partner;
+	/** Collector information */
+	struct eth_slow_lacp_collector_tlv collector;
+	/** Terminator */
+	struct eth_slow_terminator_tlv terminator;
+	/** Reserved */
+	uint8_t reserved[50];
+} __attribute__ (( packed ));
+
+/** Marker packet */
+struct eth_slow_marker {
+	/** Slow protocols header */
+	struct eth_slow_header header;
+	/** Marker information */
+	struct eth_slow_marker_tlv marker;
+	/** Terminator */
+	struct eth_slow_terminator_tlv terminator;
+	/** Reserved */
+	uint8_t reserved[90];
+} __attribute__ (( packed ));
+
+/** Slow protocols packet */
+union eth_slow_packet {
+	/** Slow protocols header */
+	struct eth_slow_header header;
+	/** LACP packet */
+	struct eth_slow_lacp lacp;
+	/** Marker packet */
+	struct eth_slow_marker marker;
+} __attribute__ (( packed ));
+
+#endif /* _IPXE_ETH_SLOW_H */

src/net/eth_slow.c

@@ -0,0 +1,267 @@
+/*
+ * Copyright (C) 2010 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <stdlib.h>
+#include <string.h>
+#include <byteswap.h>
+#include <errno.h>
+#include <ipxe/iobuf.h>
+#include <ipxe/netdevice.h>
+#include <ipxe/if_ether.h>
+#include <ipxe/ethernet.h>
+#include <ipxe/eth_slow.h>
+
+/** @file
+ *
+ * Ethernet slow protocols
+ *
+ * We implement a very simple passive LACP entity, that pretends that
+ * each port is the only port on an individual system.  We avoid the
+ * need for timeout logic (and retaining local state about our
+ * partner) by requesting the same timeout period (1s or 30s) as our
+ * partner requests, and then simply responding to every packet the
+ * partner sends us.
+ */
+
+struct net_protocol eth_slow_protocol;
+
+/** Slow protocols multicast address */
+static const uint8_t eth_slow_address[ETH_ALEN] =
+	{ 0x01, 0x80, 0xc2, 0x00, 0x00, 0x02 };
+
+/**
+ * Name LACP TLV type
+ *
+ * @v type		LACP TLV type
+ * @ret name		Name of LACP TLV type
+ */
+static inline __attribute__ (( always_inline )) const char *
+eth_slow_lacp_tlv_name ( uint8_t type ) {
+	switch ( type ) {
+	case ETH_SLOW_TLV_TERMINATOR:		return "terminator";
+	case ETH_SLOW_TLV_LACP_ACTOR:		return "actor";
+	case ETH_SLOW_TLV_LACP_PARTNER:		return "partner";
+	case ETH_SLOW_TLV_LACP_COLLECTOR:	return "collector";
+	default:				return "<invalid>";
+	}
+}
+
+/**
+ * Name marker TLV type
+ *
+ * @v type		Marker TLV type
+ * @ret name		Name of marker TLV type
+ */
+static inline __attribute__ (( always_inline )) const char *
+eth_slow_marker_tlv_name ( uint8_t type ) {
+	switch ( type ) {
+	case ETH_SLOW_TLV_TERMINATOR:		return "terminator";
+	case ETH_SLOW_TLV_MARKER_REQUEST:	return "request";
+	case ETH_SLOW_TLV_MARKER_RESPONSE:	return "response";
+	default:				return "<invalid>";
+	}
+}
+
+/**
+ * Name LACP state
+ *
+ * @v state		LACP state
+ * @ret name		LACP state name
+ */
+static const char * eth_slow_lacp_state_name ( uint8_t state ) {
+	static char state_chars[] = "AFGSRTLX";
+	unsigned int i;
+
+	for ( i = 0 ; i < 8 ; i++ ) {
+		state_chars[i] |= 0x20;
+		if ( state & ( 1 << i ) )
+			state_chars[i] &= ~0x20;
+	}
+	return state_chars;
+}
+
+/**
+ * Dump LACP packet
+ *
+ * @v iobuf		I/O buffer
+ * @v netdev		Network device
+ * @v label		"RX" or "TX"
+ */
+static void eth_slow_lacp_dump ( struct io_buffer *iobuf,
+				 struct net_device *netdev,
+				 const char *label ) {
+	union eth_slow_packet *eth_slow = iobuf->data;
+	struct eth_slow_lacp *lacp = &eth_slow->lacp;
+
+	DBGC ( netdev,
+	       "SLOW %p %s LACP actor (%04x,%s,%04x,%02x,%04x) [%s]\n",
+	       netdev, label, ntohs ( lacp->actor.system_priority ),
+	       eth_ntoa ( lacp->actor.system ),
+	       ntohs ( lacp->actor.key ),
+	       ntohs ( lacp->actor.port_priority ),
+	       ntohs ( lacp->actor.port ),
+	       eth_slow_lacp_state_name ( lacp->actor.state ) );
+	DBGC ( netdev,
+	       "SLOW %p %s LACP partner (%04x,%s,%04x,%02x,%04x) [%s]\n",
+	       netdev, label, ntohs ( lacp->partner.system_priority ),
+	       eth_ntoa ( lacp->partner.system ),
+	       ntohs ( lacp->partner.key ),
+	       ntohs ( lacp->partner.port_priority ),
+	       ntohs ( lacp->partner.port ),
+	       eth_slow_lacp_state_name ( lacp->partner.state ) );
+	DBGC ( netdev, "SLOW %p %s LACP collector %04x (%d us)\n",
+	       netdev, label, ntohs ( lacp->collector.max_delay ),
+	       ( ntohs ( lacp->collector.max_delay ) * 10 ) );
+	DBGC2_HDA ( netdev, 0, iobuf, iob_len ( iobuf ) );
+}
+
+/**
+ * Process incoming LACP packet
+ *
+ * @v iobuf		I/O buffer
+ * @v netdev		Network device
+ * @ret rc		Return status code
+ */
+static int eth_slow_lacp_rx ( struct io_buffer *iobuf,
+			      struct net_device *netdev ) {
+	union eth_slow_packet *eth_slow = iobuf->data;
+	struct eth_slow_lacp *lacp = &eth_slow->lacp;
+
+	eth_slow_lacp_dump ( iobuf, netdev, "RX" );
+
+	/* Build response */
+	memset ( lacp->reserved, 0, sizeof ( lacp->reserved ) );
+	memset ( &lacp->terminator, 0, sizeof ( lacp->terminator ) );
+	memset ( &lacp->collector, 0, sizeof ( lacp->collector ) );
+	lacp->collector.tlv.type = ETH_SLOW_TLV_LACP_COLLECTOR;
+	lacp->collector.tlv.length = ETH_SLOW_TLV_LACP_COLLECTOR_LEN;
+	memcpy ( &lacp->partner, &lacp->actor, sizeof ( lacp->partner ) );
+	lacp->partner.tlv.type = ETH_SLOW_TLV_LACP_PARTNER;
+	lacp->partner.tlv.length = ETH_SLOW_TLV_LACP_PARTNER_LEN;
+	memset ( &lacp->partner.reserved, 0,
+		 sizeof ( lacp->partner.reserved ) );
+	memset ( &lacp->actor, 0, sizeof ( lacp->actor ) );
+	lacp->actor.tlv.type = ETH_SLOW_TLV_LACP_ACTOR;
+	lacp->actor.tlv.length = ETH_SLOW_TLV_LACP_ACTOR_LEN;
+	lacp->actor.system_priority = htons ( LACP_SYSTEM_PRIORITY_MAX );
+	memcpy ( lacp->actor.system, netdev->ll_addr,
+		 sizeof ( lacp->actor.system ) );
+	lacp->actor.key = htons ( 1 );
+	lacp->actor.port_priority = htons ( LACP_PORT_PRIORITY_MAX );
+	lacp->actor.port = htons ( 1 );
+	lacp->actor.state = ( LACP_STATE_IN_SYNC |
+			      LACP_STATE_COLLECTING |
+			      LACP_STATE_DISTRIBUTING |
+			      ( lacp->partner.state & LACP_STATE_FAST ) );
+	lacp->header.version = ETH_SLOW_LACP_VERSION;
+
+	/* Send response */
+	eth_slow_lacp_dump ( iobuf, netdev, "TX" );
+	return net_tx ( iobuf, netdev, &eth_slow_protocol, eth_slow_address );
+}
+
+/**
+ * Dump marker packet
+ *
+ * @v iobuf		I/O buffer
+ * @v netdev		Network device
+ * @v label		"RX" or "TX"
+ */
+static void eth_slow_marker_dump ( struct io_buffer *iobuf,
+				   struct net_device *netdev,
+				   const char *label ) {
+	union eth_slow_packet *eth_slow = iobuf->data;
+	struct eth_slow_marker *marker = &eth_slow->marker;
+
+	DBGC ( netdev, "SLOW %p %s marker %s port %04x system %s xact %08x\n",
+	       netdev, label,
+	       eth_slow_marker_tlv_name ( marker->marker.tlv.type ),
+	       ntohs ( marker->marker.port ),
+	       eth_ntoa ( marker->marker.system ),
+	       ntohl ( marker->marker.xact ) );
+	DBGC2_HDA ( netdev, 0, iobuf, iob_len ( iobuf ) );
+}
+
+/**
+ * Process incoming marker packet
+ *
+ * @v iobuf		I/O buffer
+ * @v netdev		Network device
+ * @ret rc		Return status code
+ */
+static int eth_slow_marker_rx ( struct io_buffer *iobuf,
+				struct net_device *netdev ) {
+	union eth_slow_packet *eth_slow = iobuf->data;
+	struct eth_slow_marker *marker = &eth_slow->marker;
+
+	eth_slow_marker_dump ( iobuf, netdev, "RX" );
+
+	if ( marker->marker.tlv.type == ETH_SLOW_TLV_MARKER_REQUEST ) {
+		/* Send marker response */
+		marker->marker.tlv.type = ETH_SLOW_TLV_MARKER_RESPONSE;
+		eth_slow_marker_dump ( iobuf, netdev, "TX" );
+		return net_tx ( iobuf, netdev, &eth_slow_protocol,
+				eth_slow_address );
+	} else {
+		/* Discard all other marker packets */
+		free_iob ( iobuf );
+		return -EINVAL;
+	}
+}
+
+/**
+ * Process incoming slow packet
+ *
+ * @v iobuf		I/O buffer
+ * @v netdev		Network device
+ * @v ll_source		Link-layer source address
+ * @ret rc		Return status code
+ */
+static int eth_slow_rx ( struct io_buffer *iobuf,
+			 struct net_device *netdev,
+			 const void *ll_source __unused ) {
+	union eth_slow_packet *eth_slow = iobuf->data;
+
+	/* Sanity checks */
+	if ( iob_len ( iobuf ) < sizeof ( *eth_slow ) ) {
+		free_iob ( iobuf );
+		return -EINVAL;
+	}
+
+	/* Handle according to subtype */
+	switch ( eth_slow->header.subtype ) {
+	case ETH_SLOW_SUBTYPE_LACP:
+		return eth_slow_lacp_rx ( iobuf, netdev );
+	case ETH_SLOW_SUBTYPE_MARKER:
+		return eth_slow_marker_rx ( iobuf, netdev );
+	default:
+		DBGC ( netdev, "SLOW %p RX unknown subtype %02x\n",
+		       netdev, eth_slow->header.subtype );
+		free_iob ( iobuf );
+		return -EINVAL;
+	}
+}
+
+/** Slow protocol */
+struct net_protocol eth_slow_protocol __net_protocol = {
+	.name = "Slow",
+	.net_proto = htons ( ETH_P_SLOW ),
+	.rx = eth_slow_rx,
+};

src/net/ethernet.c

@@ -191,3 +191,6 @@ struct net_device * alloc_etherdev ( size_t priv_size ) {
 	}
 	return netdev;
 }
+
+/* Drag in Ethernet slow protocols */
+REQUIRE_OBJECT ( eth_slow );