bridge: cfm: Kernel space implementation of CFM. CCM frame RX added. (dc32cbb3) · Commits · 戴 / test

include/uapi/linux/cfm_bridge.h

+4 −0

Original line number	Diff line number	Diff line
		@@ -20,6 +20,10 @@
		CFM_IF_STATUS_TLV_LENGTH)
		#define CFM_FRAME_PRIO 7
		#define CFM_CCM_TLV_OFFSET 70
		#define CFM_CCM_PDU_MAID_OFFSET 10
		#define CFM_CCM_PDU_MEPID_OFFSET 8
		#define CFM_CCM_PDU_SEQNR_OFFSET 4
		#define CFM_CCM_PDU_TLV_OFFSET 74
		#define CFM_CCM_ITU_RESERVED_SIZE 16

		struct br_cfm_common_hdr {

net/bridge/br_cfm.c

+269 −0

Original line number	Diff line number	Diff line
		@@ -101,6 +101,56 @@ static u32 interval_to_pdu(enum br_cfm_ccm_interval interval)
		return 0;
		}

		/* Convert the CCM PDU value to interval on interface. */
		static u32 pdu_to_interval(u32 value)
		{
		switch (value) {
		case 0:
		return BR_CFM_CCM_INTERVAL_NONE;
		case 1:
		return BR_CFM_CCM_INTERVAL_3_3_MS;
		case 2:
		return BR_CFM_CCM_INTERVAL_10_MS;
		case 3:
		return BR_CFM_CCM_INTERVAL_100_MS;
		case 4:
		return BR_CFM_CCM_INTERVAL_1_SEC;
		case 5:
		return BR_CFM_CCM_INTERVAL_10_SEC;
		case 6:
		return BR_CFM_CCM_INTERVAL_1_MIN;
		case 7:
		return BR_CFM_CCM_INTERVAL_10_MIN;
		}
		return BR_CFM_CCM_INTERVAL_NONE;
		}

		static void ccm_rx_timer_start(struct br_cfm_peer_mep *peer_mep)
		{
		u32 interval_us;

		interval_us = interval_to_us(peer_mep->mep->cc_config.exp_interval);
		/* Function ccm_rx_dwork must be called with 1/4
		* of the configured CC 'expected_interval'
		* in order to detect CCM defect after 3.25 interval.
		*/
		queue_delayed_work(system_wq, &peer_mep->ccm_rx_dwork,
		usecs_to_jiffies(interval_us / 4));
		}

		static void cc_peer_enable(struct br_cfm_peer_mep *peer_mep)
		{
		memset(&peer_mep->cc_status, 0, sizeof(peer_mep->cc_status));
		peer_mep->ccm_rx_count_miss = 0;

		ccm_rx_timer_start(peer_mep);
		}

		static void cc_peer_disable(struct br_cfm_peer_mep *peer_mep)
		{
		cancel_delayed_work_sync(&peer_mep->ccm_rx_dwork);
		}

		static struct sk_buff ccm_frame_build(struct br_cfm_mep mep,
		const struct br_cfm_cc_ccm_tx_info *const tx_info)

		@@ -232,6 +282,200 @@ static void ccm_tx_work_expired(struct work_struct *work)
		usecs_to_jiffies(interval_us));
		}

		/* This function is called with 1/4 of the configured CC 'expected_interval'
		* in order to detect CCM defect after 3.25 interval.
		*/
		static void ccm_rx_work_expired(struct work_struct *work)
		{
		struct br_cfm_peer_mep *peer_mep;
		struct delayed_work *del_work;

		del_work = to_delayed_work(work);
		peer_mep = container_of(del_work, struct br_cfm_peer_mep, ccm_rx_dwork);

		/* After 13 counts (4 * 3,25) then 3.25 intervals are expired */
		if (peer_mep->ccm_rx_count_miss < 13) {
		/* 3.25 intervals are NOT expired without CCM reception */
		peer_mep->ccm_rx_count_miss++;

		/* Start timer again */
		ccm_rx_timer_start(peer_mep);
		} else {
		/* 3.25 intervals are expired without CCM reception.
		* CCM defect detected
		*/
		peer_mep->cc_status.ccm_defect = true;
		}
		}

		static u32 ccm_tlv_extract(struct sk_buff *skb, u32 index,
		struct br_cfm_peer_mep *peer_mep)
		{
		__be32 *s_tlv;
		__be32 _s_tlv;
		u32 h_s_tlv;
		u8 *e_tlv;
		u8 _e_tlv;

		e_tlv = skb_header_pointer(skb, index, sizeof(_e_tlv), &_e_tlv);
		if (!e_tlv)
		return 0;

		/* TLV is present - get the status TLV */
		s_tlv = skb_header_pointer(skb,
		index,
		sizeof(_s_tlv), &_s_tlv);
		if (!s_tlv)
		return 0;

		h_s_tlv = ntohl(*s_tlv);
		if ((h_s_tlv >> 24) == CFM_IF_STATUS_TLV_TYPE) {
		/* Interface status TLV */
		peer_mep->cc_status.tlv_seen = true;
		peer_mep->cc_status.if_tlv_value = (h_s_tlv & 0xFF);
		}

		if ((h_s_tlv >> 24) == CFM_PORT_STATUS_TLV_TYPE) {
		/* Port status TLV */
		peer_mep->cc_status.tlv_seen = true;
		peer_mep->cc_status.port_tlv_value = (h_s_tlv & 0xFF);
		}

		/* The Sender ID TLV is not handled */
		/* The Organization-Specific TLV is not handled */

		/* Return the length of this tlv.
		* This is the length of the value field plus 3 bytes for size of type
		* field and length field
		*/
		return ((h_s_tlv >> 8) & 0xFFFF) + 3;
		}

		/* note: already called with rcu_read_lock */
		static int br_cfm_frame_rx(struct net_bridge_port port, struct sk_buff skb)
		{
		u32 mdlevel, interval, size, index, max;
		const struct br_cfm_common_hdr *hdr;
		struct br_cfm_peer_mep *peer_mep;
		const struct br_cfm_maid *maid;
		struct br_cfm_common_hdr _hdr;
		struct br_cfm_maid _maid;
		struct br_cfm_mep *mep;
		struct net_bridge *br;
		__be32 *snumber;
		__be32 _snumber;
		__be16 *mepid;
		__be16 _mepid;

		if (port->state == BR_STATE_DISABLED)
		return 0;

		hdr = skb_header_pointer(skb, 0, sizeof(_hdr), &_hdr);
		if (!hdr)
		return 1;

		br = port->br;
		mep = br_mep_find_ifindex(br, port->dev->ifindex);
		if (unlikely(!mep))
		/* No MEP on this port - must be forwarded */
		return 0;

		mdlevel = hdr->mdlevel_version >> 5;
		if (mdlevel > mep->config.mdlevel)
		/* The level is above this MEP level - must be forwarded */
		return 0;

		if ((hdr->mdlevel_version & 0x1F) != 0) {
		/* Invalid version */
		mep->status.version_unexp_seen = true;
		return 1;
		}

		if (mdlevel < mep->config.mdlevel) {
		/* The level is below this MEP level */
		mep->status.rx_level_low_seen = true;
		return 1;
		}

		if (hdr->opcode == BR_CFM_OPCODE_CCM) {
		/* CCM PDU received. */
		/* MA ID is after common header + sequence number + MEP ID */
		maid = skb_header_pointer(skb,
		CFM_CCM_PDU_MAID_OFFSET,
		sizeof(_maid), &_maid);
		if (!maid)
		return 1;
		if (memcmp(maid->data, mep->cc_config.exp_maid.data,
		sizeof(maid->data)))
		/* MA ID not as expected */
		return 1;

		/* MEP ID is after common header + sequence number */
		mepid = skb_header_pointer(skb,
		CFM_CCM_PDU_MEPID_OFFSET,
		sizeof(_mepid), &_mepid);
		if (!mepid)
		return 1;
		peer_mep = br_peer_mep_find(mep, (u32)ntohs(*mepid));
		if (!peer_mep)
		return 1;

		/* Interval is in common header flags */
		interval = hdr->flags & 0x07;
		if (mep->cc_config.exp_interval != pdu_to_interval(interval))
		/* Interval not as expected */
		return 1;

		/* A valid CCM frame is received */
		if (peer_mep->cc_status.ccm_defect) {
		peer_mep->cc_status.ccm_defect = false;

		/* Start CCM RX timer */
		ccm_rx_timer_start(peer_mep);
		}

		peer_mep->cc_status.seen = true;
		peer_mep->ccm_rx_count_miss = 0;

		/* RDI is in common header flags */
		peer_mep->cc_status.rdi = (hdr->flags & 0x80) ? true : false;

		/* Sequence number is after common header */
		snumber = skb_header_pointer(skb,
		CFM_CCM_PDU_SEQNR_OFFSET,
		sizeof(_snumber), &_snumber);
		if (!snumber)
		return 1;
		if (ntohl(*snumber) != (mep->ccm_rx_snumber + 1))
		/* Unexpected sequence number */
		peer_mep->cc_status.seq_unexp_seen = true;

		mep->ccm_rx_snumber = ntohl(*snumber);

		/* TLV end is after common header + sequence number + MEP ID +
		* MA ID + ITU reserved
		*/
		index = CFM_CCM_PDU_TLV_OFFSET;
		max = 0;
		do { /* Handle all TLVs */
		size = ccm_tlv_extract(skb, index, peer_mep);
		index += size;
		max += 1;
		} while (size != 0 && max < 4); /* Max four TLVs possible */

		return 1;
		}

		mep->status.opcode_unexp_seen = true;

		return 1;
		}

		static struct br_frame_type cfm_frame_type __read_mostly = {
		.type = cpu_to_be16(ETH_P_CFM),
		.frame_handler = br_cfm_frame_rx,
		};

		int br_cfm_mep_create(struct net_bridge *br,
		const u32 instance,
		struct br_cfm_mep_create *const create,
		@@ -296,6 +540,9 @@ int br_cfm_mep_create(struct net_bridge *br,
		INIT_HLIST_HEAD(&mep->peer_mep_list);
		INIT_DELAYED_WORK(&mep->ccm_tx_dwork, ccm_tx_work_expired);

		if (hlist_empty(&br->mep_list))
		br_add_frame(br, &cfm_frame_type);

		hlist_add_tail_rcu(&mep->head, &br->mep_list);

		return 0;
		@@ -311,6 +558,7 @@ static void mep_delete_implementation(struct net_bridge *br,

		/* Empty and free peer MEP list */
		hlist_for_each_entry_safe(peer_mep, n_store, &mep->peer_mep_list, head) {
		cancel_delayed_work_sync(&peer_mep->ccm_rx_dwork);
		hlist_del_rcu(&peer_mep->head);
		kfree_rcu(peer_mep, rcu);
		}
		@@ -320,6 +568,9 @@ static void mep_delete_implementation(struct net_bridge *br,
		RCU_INIT_POINTER(mep->b_port, NULL);
		hlist_del_rcu(&mep->head);
		kfree_rcu(mep, rcu);

		if (hlist_empty(&br->mep_list))
		br_del_frame(br, &cfm_frame_type);
		}

		int br_cfm_mep_delete(struct net_bridge *br,
		@@ -368,6 +619,7 @@ int br_cfm_cc_config_set(struct net_bridge *br,
		const struct br_cfm_cc_config *const config,
		struct netlink_ext_ack *extack)
		{
		struct br_cfm_peer_mep *peer_mep;
		struct br_cfm_mep *mep;

		ASSERT_RTNL();
		@@ -383,7 +635,18 @@ int br_cfm_cc_config_set(struct net_bridge *br,
		if (memcmp(config, &mep->cc_config, sizeof(*config)) == 0)
		return 0;

		if (config->enable && !mep->cc_config.enable)
		/* CC is enabled */
		hlist_for_each_entry(peer_mep, &mep->peer_mep_list, head)
		cc_peer_enable(peer_mep);

		if (!config->enable && mep->cc_config.enable)
		/* CC is disabled */
		hlist_for_each_entry(peer_mep, &mep->peer_mep_list, head)
		cc_peer_disable(peer_mep);

		mep->cc_config = *config;
		mep->ccm_rx_snumber = 0;
		mep->ccm_tx_snumber = 1;

		return 0;
		@@ -418,6 +681,10 @@ int br_cfm_cc_peer_mep_add(struct net_bridge *br, const u32 instance,

		peer_mep->mepid = mepid;
		peer_mep->mep = mep;
		INIT_DELAYED_WORK(&peer_mep->ccm_rx_dwork, ccm_rx_work_expired);

		if (mep->cc_config.enable)
		cc_peer_enable(peer_mep);

		hlist_add_tail_rcu(&peer_mep->head, &mep->peer_mep_list);

		@@ -447,6 +714,8 @@ int br_cfm_cc_peer_mep_remove(struct net_bridge *br, const u32 instance,
		return -ENOENT;
		}

		cc_peer_disable(peer_mep);

		hlist_del_rcu(&peer_mep->head);
		kfree_rcu(peer_mep, rcu);

net/bridge/br_private_cfm.h

+32 −0

Original line number	Diff line number	Diff line
		@@ -43,6 +43,8 @@ struct br_cfm_cc_config {
		/* Expected received CCM PDU interval. */
		/* Transmitting CCM PDU interval when CCM tx is enabled. */
		enum br_cfm_ccm_interval exp_interval;

		bool enable; /* Enable/disable CCM PDU handling */
		};

		int br_cfm_cc_config_set(struct net_bridge *br,
		@@ -87,6 +89,31 @@ int br_cfm_cc_ccm_tx(struct net_bridge *br, const u32 instance,
		const struct br_cfm_cc_ccm_tx_info *const tx_info,
		struct netlink_ext_ack *extack);

		struct br_cfm_mep_status {
		/* Indications that an OAM PDU has been seen. */
		bool opcode_unexp_seen; /* RX of OAM PDU with unexpected opcode */
		bool version_unexp_seen; /* RX of OAM PDU with unexpected version */
		bool rx_level_low_seen; /* Rx of OAM PDU with level low */
		};

		struct br_cfm_cc_peer_status {
		/* This CCM related status is based on the latest received CCM PDU. */
		u8 port_tlv_value; /* Port Status TLV value */
		u8 if_tlv_value; /* Interface Status TLV value */

		/* CCM has not been received for 3.25 intervals */
		u8 ccm_defect:1;

		/* (RDI == 1) for last received CCM PDU */
		u8 rdi:1;

		/* Indications that a CCM PDU has been seen. */
		u8 seen:1; /* CCM PDU received */
		u8 tlv_seen:1; /* CCM PDU with TLV received */
		/* CCM PDU with unexpected sequence number received */
		u8 seq_unexp_seen:1;
		};

		struct br_cfm_mep {
		/* list header of MEP instances */
		struct hlist_node head;
		@@ -101,6 +128,8 @@ struct br_cfm_mep {
		unsigned long ccm_tx_end;
		struct delayed_work ccm_tx_dwork;
		u32 ccm_tx_snumber;
		u32 ccm_rx_snumber;
		struct br_cfm_mep_status status;
		bool rdi;
		struct rcu_head rcu;
		};
		@@ -108,7 +137,10 @@ struct br_cfm_mep {
		struct br_cfm_peer_mep {
		struct hlist_node head;
		struct br_cfm_mep *mep;
		struct delayed_work ccm_rx_dwork;
		u32 mepid;
		struct br_cfm_cc_peer_status cc_status;
		u32 ccm_rx_count_miss;
		struct rcu_head rcu;
		};

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