Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1451 insertions, 0 deletions

diff --git a/net/llc/llc_c_ac.c b/net/llc/llc_c_ac.c
new file mode 100644
index 000000000..647c0554d
--- /dev/null
+++ b/net/llc/llc_c_ac.c
@@ -0,0 +1,1451 @@
+/*
+ * llc_c_ac.c - actions performed during connection state transition.
+ *
+ * Description:
+ *   Functions in this module are implementation of connection component actions
+ *   Details of actions can be found in IEEE-802.2 standard document.
+ *   All functions have one connection and one event as input argument. All of
+ *   them return 0 On success and 1 otherwise.
+ *
+ * Copyright (c) 1997 by Procom Technology, Inc.
+ * 		 2001-2003 by Arnaldo Carvalho de Melo <acme@conectiva.com.br>
+ *
+ * This program can be redistributed or modified under the terms of the
+ * GNU General Public License as published by the Free Software Foundation.
+ * This program is distributed without any warranty or implied warranty
+ * of merchantability or fitness for a particular purpose.
+ *
+ * See the GNU General Public License for more details.
+ */
+#include <linux/netdevice.h>
+#include <linux/slab.h>
+#include <net/llc_conn.h>
+#include <net/llc_sap.h>
+#include <net/sock.h>
+#include <net/llc_c_ev.h>
+#include <net/llc_c_ac.h>
+#include <net/llc_c_st.h>
+#include <net/llc_pdu.h>
+#include <net/llc.h>
+
+
+static int llc_conn_ac_inc_vs_by_1(struct sock *sk, struct sk_buff *skb);
+static void llc_process_tmr_ev(struct sock *sk, struct sk_buff *skb);
+static int llc_conn_ac_data_confirm(struct sock *sk, struct sk_buff *ev);
+
+static int llc_conn_ac_inc_npta_value(struct sock *sk, struct sk_buff *skb);
+
+static int llc_conn_ac_send_rr_rsp_f_set_ackpf(struct sock *sk,
+					       struct sk_buff *skb);
+
+static int llc_conn_ac_set_p_flag_1(struct sock *sk, struct sk_buff *skb);
+
+#define INCORRECT 0
+
+int llc_conn_ac_clear_remote_busy(struct sock *sk, struct sk_buff *skb)
+{
+	struct llc_sock *llc = llc_sk(sk);
+
+	if (llc->remote_busy_flag) {
+		u8 nr;
+		struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
+
+		llc->remote_busy_flag = 0;
+		del_timer(&llc->busy_state_timer.timer);
+		nr = LLC_I_GET_NR(pdu);
+		llc_conn_resend_i_pdu_as_cmd(sk, nr, 0);
+	}
+	return 0;
+}
+
+int llc_conn_ac_conn_ind(struct sock *sk, struct sk_buff *skb)
+{
+	struct llc_conn_state_ev *ev = llc_conn_ev(skb);
+
+	ev->ind_prim = LLC_CONN_PRIM;
+	return 0;
+}
+
+int llc_conn_ac_conn_confirm(struct sock *sk, struct sk_buff *skb)
+{
+	struct llc_conn_state_ev *ev = llc_conn_ev(skb);
+
+	ev->cfm_prim = LLC_CONN_PRIM;
+	return 0;
+}
+
+static int llc_conn_ac_data_confirm(struct sock *sk, struct sk_buff *skb)
+{
+	struct llc_conn_state_ev *ev = llc_conn_ev(skb);
+
+	ev->cfm_prim = LLC_DATA_PRIM;
+	return 0;
+}
+
+int llc_conn_ac_data_ind(struct sock *sk, struct sk_buff *skb)
+{
+	llc_conn_rtn_pdu(sk, skb);
+	return 0;
+}
+
+int llc_conn_ac_disc_ind(struct sock *sk, struct sk_buff *skb)
+{
+	struct llc_conn_state_ev *ev = llc_conn_ev(skb);
+	u8 reason = 0;
+	int rc = 0;
+
+	if (ev->type == LLC_CONN_EV_TYPE_PDU) {
+		struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb);
+
+		if (LLC_PDU_IS_RSP(pdu) &&
+		    LLC_PDU_TYPE_IS_U(pdu) &&
+		    LLC_U_PDU_RSP(pdu) == LLC_2_PDU_RSP_DM)
+			reason = LLC_DISC_REASON_RX_DM_RSP_PDU;
+		else if (LLC_PDU_IS_CMD(pdu) &&
+			   LLC_PDU_TYPE_IS_U(pdu) &&
+			   LLC_U_PDU_CMD(pdu) == LLC_2_PDU_CMD_DISC)
+			reason = LLC_DISC_REASON_RX_DISC_CMD_PDU;
+	} else if (ev->type == LLC_CONN_EV_TYPE_ACK_TMR)
+		reason = LLC_DISC_REASON_ACK_TMR_EXP;
+	else
+		rc = -EINVAL;
+	if (!rc) {
+		ev->reason   = reason;
+		ev->ind_prim = LLC_DISC_PRIM;
+	}
+	return rc;
+}
+
+int llc_conn_ac_disc_confirm(struct sock *sk, struct sk_buff *skb)
+{
+	struct llc_conn_state_ev *ev = llc_conn_ev(skb);
+
+	ev->reason   = ev->status;
+	ev->cfm_prim = LLC_DISC_PRIM;
+	return 0;
+}
+
+int llc_conn_ac_rst_ind(struct sock *sk, struct sk_buff *skb)
+{
+	u8 reason = 0;
+	int rc = 1;
+	struct llc_conn_state_ev *ev = llc_conn_ev(skb);
+	struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb);
+	struct llc_sock *llc = llc_sk(sk);
+
+	switch (ev->type) {
+	case LLC_CONN_EV_TYPE_PDU:
+		if (LLC_PDU_IS_RSP(pdu) &&
+		    LLC_PDU_TYPE_IS_U(pdu) &&
+		    LLC_U_PDU_RSP(pdu) == LLC_2_PDU_RSP_FRMR) {
+			reason = LLC_RESET_REASON_LOCAL;
+			rc = 0;
+		} else if (LLC_PDU_IS_CMD(pdu) &&
+			   LLC_PDU_TYPE_IS_U(pdu) &&
+			   LLC_U_PDU_CMD(pdu) == LLC_2_PDU_CMD_SABME) {
+			reason = LLC_RESET_REASON_REMOTE;
+			rc = 0;
+		}
+		break;
+	case LLC_CONN_EV_TYPE_ACK_TMR:
+	case LLC_CONN_EV_TYPE_P_TMR:
+	case LLC_CONN_EV_TYPE_REJ_TMR:
+	case LLC_CONN_EV_TYPE_BUSY_TMR:
+		if (llc->retry_count > llc->n2) {
+			reason = LLC_RESET_REASON_LOCAL;
+			rc = 0;
+		}
+		break;
+	}
+	if (!rc) {
+		ev->reason   = reason;
+		ev->ind_prim = LLC_RESET_PRIM;
+	}
+	return rc;
+}
+
+int llc_conn_ac_rst_confirm(struct sock *sk, struct sk_buff *skb)
+{
+	struct llc_conn_state_ev *ev = llc_conn_ev(skb);
+
+	ev->reason   = 0;
+	ev->cfm_prim = LLC_RESET_PRIM;
+	return 0;
+}
+
+int llc_conn_ac_clear_remote_busy_if_f_eq_1(struct sock *sk,
+					    struct sk_buff *skb)
+{
+	struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
+
+	if (LLC_PDU_IS_RSP(pdu) &&
+	    LLC_PDU_TYPE_IS_I(pdu) &&
+	    LLC_I_PF_IS_1(pdu) && llc_sk(sk)->ack_pf)
+		llc_conn_ac_clear_remote_busy(sk, skb);
+	return 0;
+}
+
+int llc_conn_ac_stop_rej_tmr_if_data_flag_eq_2(struct sock *sk,
+					       struct sk_buff *skb)
+{
+	struct llc_sock *llc = llc_sk(sk);
+
+	if (llc->data_flag == 2)
+		del_timer(&llc->rej_sent_timer.timer);
+	return 0;
+}
+
+int llc_conn_ac_send_disc_cmd_p_set_x(struct sock *sk, struct sk_buff *skb)
+{
+	int rc = -ENOBUFS;
+	struct llc_sock *llc = llc_sk(sk);
+	struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_U, 0);
+
+	if (nskb) {
+		struct llc_sap *sap = llc->sap;
+
+		llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
+				    llc->daddr.lsap, LLC_PDU_CMD);
+		llc_pdu_init_as_disc_cmd(nskb, 1);
+		rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
+		if (unlikely(rc))
+			goto free;
+		llc_conn_send_pdu(sk, nskb);
+		llc_conn_ac_set_p_flag_1(sk, skb);
+	}
+out:
+	return rc;
+free:
+	kfree_skb(nskb);
+	goto out;
+}
+
+int llc_conn_ac_send_dm_rsp_f_set_p(struct sock *sk, struct sk_buff *skb)
+{
+	int rc = -ENOBUFS;
+	struct llc_sock *llc = llc_sk(sk);
+	struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_U, 0);
+
+	if (nskb) {
+		struct llc_sap *sap = llc->sap;
+		u8 f_bit;
+
+		llc_pdu_decode_pf_bit(skb, &f_bit);
+		llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
+				    llc->daddr.lsap, LLC_PDU_RSP);
+		llc_pdu_init_as_dm_rsp(nskb, f_bit);
+		rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
+		if (unlikely(rc))
+			goto free;
+		llc_conn_send_pdu(sk, nskb);
+	}
+out:
+	return rc;
+free:
+	kfree_skb(nskb);
+	goto out;
+}
+
+int llc_conn_ac_send_dm_rsp_f_set_1(struct sock *sk, struct sk_buff *skb)
+{
+	int rc = -ENOBUFS;
+	struct llc_sock *llc = llc_sk(sk);
+	struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_U, 0);
+
+	if (nskb) {
+		struct llc_sap *sap = llc->sap;
+
+		llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
+				    llc->daddr.lsap, LLC_PDU_RSP);
+		llc_pdu_init_as_dm_rsp(nskb, 1);
+		rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
+		if (unlikely(rc))
+			goto free;
+		llc_conn_send_pdu(sk, nskb);
+	}
+out:
+	return rc;
+free:
+	kfree_skb(nskb);
+	goto out;
+}
+
+int llc_conn_ac_send_frmr_rsp_f_set_x(struct sock *sk, struct sk_buff *skb)
+{
+	u8 f_bit;
+	int rc = -ENOBUFS;
+	struct sk_buff *nskb;
+	struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
+	struct llc_sock *llc = llc_sk(sk);
+
+	llc->rx_pdu_hdr = *((u32 *)pdu);
+	if (LLC_PDU_IS_CMD(pdu))
+		llc_pdu_decode_pf_bit(skb, &f_bit);
+	else
+		f_bit = 0;
+	nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_U,
+			       sizeof(struct llc_frmr_info));
+	if (nskb) {
+		struct llc_sap *sap = llc->sap;
+
+		llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
+				    llc->daddr.lsap, LLC_PDU_RSP);
+		llc_pdu_init_as_frmr_rsp(nskb, pdu, f_bit, llc->vS,
+					 llc->vR, INCORRECT);
+		rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
+		if (unlikely(rc))
+			goto free;
+		llc_conn_send_pdu(sk, nskb);
+	}
+out:
+	return rc;
+free:
+	kfree_skb(nskb);
+	goto out;
+}
+
+int llc_conn_ac_resend_frmr_rsp_f_set_0(struct sock *sk, struct sk_buff *skb)
+{
+	int rc = -ENOBUFS;
+	struct llc_sock *llc = llc_sk(sk);
+	struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_U,
+					       sizeof(struct llc_frmr_info));
+
+	if (nskb) {
+		struct llc_sap *sap = llc->sap;
+		struct llc_pdu_sn *pdu = (struct llc_pdu_sn *)&llc->rx_pdu_hdr;
+
+		llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
+				    llc->daddr.lsap, LLC_PDU_RSP);
+		llc_pdu_init_as_frmr_rsp(nskb, pdu, 0, llc->vS,
+					 llc->vR, INCORRECT);
+		rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
+		if (unlikely(rc))
+			goto free;
+		llc_conn_send_pdu(sk, nskb);
+	}
+out:
+	return rc;
+free:
+	kfree_skb(nskb);
+	goto out;
+}
+
+int llc_conn_ac_resend_frmr_rsp_f_set_p(struct sock *sk, struct sk_buff *skb)
+{
+	u8 f_bit;
+	int rc = -ENOBUFS;
+	struct sk_buff *nskb;
+	struct llc_sock *llc = llc_sk(sk);
+
+	llc_pdu_decode_pf_bit(skb, &f_bit);
+	nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_U,
+			       sizeof(struct llc_frmr_info));
+	if (nskb) {
+		struct llc_sap *sap = llc->sap;
+		struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
+
+		llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
+				    llc->daddr.lsap, LLC_PDU_RSP);
+		llc_pdu_init_as_frmr_rsp(nskb, pdu, f_bit, llc->vS,
+					 llc->vR, INCORRECT);
+		rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
+		if (unlikely(rc))
+			goto free;
+		llc_conn_send_pdu(sk, nskb);
+	}
+out:
+	return rc;
+free:
+	kfree_skb(nskb);
+	goto out;
+}
+
+int llc_conn_ac_send_i_cmd_p_set_1(struct sock *sk, struct sk_buff *skb)
+{
+	int rc;
+	struct llc_sock *llc = llc_sk(sk);
+	struct llc_sap *sap = llc->sap;
+
+	llc_pdu_header_init(skb, LLC_PDU_TYPE_I, sap->laddr.lsap,
+			    llc->daddr.lsap, LLC_PDU_CMD);
+	llc_pdu_init_as_i_cmd(skb, 1, llc->vS, llc->vR);
+	rc = llc_mac_hdr_init(skb, llc->dev->dev_addr, llc->daddr.mac);
+	if (likely(!rc)) {
+		skb_get(skb);
+		llc_conn_send_pdu(sk, skb);
+		llc_conn_ac_inc_vs_by_1(sk, skb);
+	}
+	return rc;
+}
+
+static int llc_conn_ac_send_i_cmd_p_set_0(struct sock *sk, struct sk_buff *skb)
+{
+	int rc;
+	struct llc_sock *llc = llc_sk(sk);
+	struct llc_sap *sap = llc->sap;
+
+	llc_pdu_header_init(skb, LLC_PDU_TYPE_I, sap->laddr.lsap,
+			    llc->daddr.lsap, LLC_PDU_CMD);
+	llc_pdu_init_as_i_cmd(skb, 0, llc->vS, llc->vR);
+	rc = llc_mac_hdr_init(skb, llc->dev->dev_addr, llc->daddr.mac);
+	if (likely(!rc)) {
+		skb_get(skb);
+		llc_conn_send_pdu(sk, skb);
+		llc_conn_ac_inc_vs_by_1(sk, skb);
+	}
+	return rc;
+}
+
+int llc_conn_ac_send_i_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
+{
+	int rc;
+	struct llc_sock *llc = llc_sk(sk);
+	struct llc_sap *sap = llc->sap;
+
+	llc_pdu_header_init(skb, LLC_PDU_TYPE_I, sap->laddr.lsap,
+			    llc->daddr.lsap, LLC_PDU_CMD);
+	llc_pdu_init_as_i_cmd(skb, 0, llc->vS, llc->vR);
+	rc = llc_mac_hdr_init(skb, llc->dev->dev_addr, llc->daddr.mac);
+	if (likely(!rc)) {
+		skb_get(skb);
+		llc_conn_send_pdu(sk, skb);
+		llc_conn_ac_inc_vs_by_1(sk, skb);
+	}
+	return 0;
+}
+
+int llc_conn_ac_resend_i_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
+{
+	struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
+	u8 nr = LLC_I_GET_NR(pdu);
+
+	llc_conn_resend_i_pdu_as_cmd(sk, nr, 0);
+	return 0;
+}
+
+int llc_conn_ac_resend_i_xxx_x_set_0_or_send_rr(struct sock *sk,
+						struct sk_buff *skb)
+{
+	u8 nr;
+	struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
+	int rc = -ENOBUFS;
+	struct llc_sock *llc = llc_sk(sk);
+	struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_U, 0);
+
+	if (nskb) {
+		struct llc_sap *sap = llc->sap;
+
+		llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
+				    llc->daddr.lsap, LLC_PDU_RSP);
+		llc_pdu_init_as_rr_rsp(nskb, 0, llc->vR);
+		rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
+		if (likely(!rc))
+			llc_conn_send_pdu(sk, nskb);
+		else
+			kfree_skb(skb);
+	}
+	if (rc) {
+		nr = LLC_I_GET_NR(pdu);
+		rc = 0;
+		llc_conn_resend_i_pdu_as_cmd(sk, nr, 0);
+	}
+	return rc;
+}
+
+int llc_conn_ac_resend_i_rsp_f_set_1(struct sock *sk, struct sk_buff *skb)
+{
+	struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
+	u8 nr = LLC_I_GET_NR(pdu);
+
+	llc_conn_resend_i_pdu_as_rsp(sk, nr, 1);
+	return 0;
+}
+
+int llc_conn_ac_send_rej_cmd_p_set_1(struct sock *sk, struct sk_buff *skb)
+{
+	int rc = -ENOBUFS;
+	struct llc_sock *llc = llc_sk(sk);
+	struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_S, 0);
+
+	if (nskb) {
+		struct llc_sap *sap = llc->sap;
+
+		llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
+				    llc->daddr.lsap, LLC_PDU_CMD);
+		llc_pdu_init_as_rej_cmd(nskb, 1, llc->vR);
+		rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
+		if (unlikely(rc))
+			goto free;
+		llc_conn_send_pdu(sk, nskb);
+	}
+out:
+	return rc;
+free:
+	kfree_skb(nskb);
+	goto out;
+}
+
+int llc_conn_ac_send_rej_rsp_f_set_1(struct sock *sk, struct sk_buff *skb)
+{
+	int rc = -ENOBUFS;
+	struct llc_sock *llc = llc_sk(sk);
+	struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_S, 0);
+
+	if (nskb) {
+		struct llc_sap *sap = llc->sap;
+
+		llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
+				    llc->daddr.lsap, LLC_PDU_RSP);
+		llc_pdu_init_as_rej_rsp(nskb, 1, llc->vR);
+		rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
+		if (unlikely(rc))
+			goto free;
+		llc_conn_send_pdu(sk, nskb);
+	}
+out:
+	return rc;
+free:
+	kfree_skb(nskb);
+	goto out;
+}
+
+int llc_conn_ac_send_rej_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
+{
+	int rc = -ENOBUFS;
+	struct llc_sock *llc = llc_sk(sk);
+	struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_S, 0);
+
+	if (nskb) {
+		struct llc_sap *sap = llc->sap;
+
+		llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
+				    llc->daddr.lsap, LLC_PDU_RSP);
+		llc_pdu_init_as_rej_rsp(nskb, 0, llc->vR);
+		rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
+		if (unlikely(rc))
+			goto free;
+		llc_conn_send_pdu(sk, nskb);
+	}
+out:
+	return rc;
+free:
+	kfree_skb(nskb);
+	goto out;
+}
+
+int llc_conn_ac_send_rnr_cmd_p_set_1(struct sock *sk, struct sk_buff *skb)
+{
+	int rc = -ENOBUFS;
+	struct llc_sock *llc = llc_sk(sk);
+	struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_S, 0);
+
+	if (nskb) {
+		struct llc_sap *sap = llc->sap;
+
+		llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
+				    llc->daddr.lsap, LLC_PDU_CMD);
+		llc_pdu_init_as_rnr_cmd(nskb, 1, llc->vR);
+		rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
+		if (unlikely(rc))
+			goto free;
+		llc_conn_send_pdu(sk, nskb);
+	}
+out:
+	return rc;
+free:
+	kfree_skb(nskb);
+	goto out;
+}
+
+int llc_conn_ac_send_rnr_rsp_f_set_1(struct sock *sk, struct sk_buff *skb)
+{
+	int rc = -ENOBUFS;
+	struct llc_sock *llc = llc_sk(sk);
+	struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_S, 0);
+
+	if (nskb) {
+		struct llc_sap *sap = llc->sap;
+
+		llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
+				    llc->daddr.lsap, LLC_PDU_RSP);
+		llc_pdu_init_as_rnr_rsp(nskb, 1, llc->vR);
+		rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
+		if (unlikely(rc))
+			goto free;
+		llc_conn_send_pdu(sk, nskb);
+	}
+out:
+	return rc;
+free:
+	kfree_skb(nskb);
+	goto out;
+}
+
+int llc_conn_ac_send_rnr_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
+{
+	int rc = -ENOBUFS;
+	struct llc_sock *llc = llc_sk(sk);
+	struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_S, 0);
+
+	if (nskb) {
+		struct llc_sap *sap = llc->sap;
+
+		llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
+				    llc->daddr.lsap, LLC_PDU_RSP);
+		llc_pdu_init_as_rnr_rsp(nskb, 0, llc->vR);
+		rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
+		if (unlikely(rc))
+			goto free;
+		llc_conn_send_pdu(sk, nskb);
+	}
+out:
+	return rc;
+free:
+	kfree_skb(nskb);
+	goto out;
+}
+
+int llc_conn_ac_set_remote_busy(struct sock *sk, struct sk_buff *skb)
+{
+	struct llc_sock *llc = llc_sk(sk);
+
+	if (!llc->remote_busy_flag) {
+		llc->remote_busy_flag = 1;
+		mod_timer(&llc->busy_state_timer.timer,
+			 jiffies + llc->busy_state_timer.expire);
+	}
+	return 0;
+}
+
+int llc_conn_ac_opt_send_rnr_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
+{
+	int rc = -ENOBUFS;
+	struct llc_sock *llc = llc_sk(sk);
+	struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_S, 0);
+
+	if (nskb) {
+		struct llc_sap *sap = llc->sap;
+
+		llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
+				    llc->daddr.lsap, LLC_PDU_RSP);
+		llc_pdu_init_as_rnr_rsp(nskb, 0, llc->vR);
+		rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
+		if (unlikely(rc))
+			goto free;
+		llc_conn_send_pdu(sk, nskb);
+	}
+out:
+	return rc;
+free:
+	kfree_skb(nskb);
+	goto out;
+}
+
+int llc_conn_ac_send_rr_cmd_p_set_1(struct sock *sk, struct sk_buff *skb)
+{
+	int rc = -ENOBUFS;
+	struct llc_sock *llc = llc_sk(sk);
+	struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_S, 0);
+
+	if (nskb) {
+		struct llc_sap *sap = llc->sap;
+
+		llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
+				    llc->daddr.lsap, LLC_PDU_CMD);
+		llc_pdu_init_as_rr_cmd(nskb, 1, llc->vR);
+		rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
+		if (unlikely(rc))
+			goto free;
+		llc_conn_send_pdu(sk, nskb);
+	}
+out:
+	return rc;
+free:
+	kfree_skb(nskb);
+	goto out;
+}
+
+int llc_conn_ac_send_rr_rsp_f_set_1(struct sock *sk, struct sk_buff *skb)
+{
+	int rc = -ENOBUFS;
+	struct llc_sock *llc = llc_sk(sk);
+	struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_S, 0);
+
+	if (nskb) {
+		struct llc_sap *sap = llc->sap;
+		u8 f_bit = 1;
+
+		llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
+				    llc->daddr.lsap, LLC_PDU_RSP);
+		llc_pdu_init_as_rr_rsp(nskb, f_bit, llc->vR);
+		rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
+		if (unlikely(rc))
+			goto free;
+		llc_conn_send_pdu(sk, nskb);
+	}
+out:
+	return rc;
+free:
+	kfree_skb(nskb);
+	goto out;
+}
+
+int llc_conn_ac_send_ack_rsp_f_set_1(struct sock *sk, struct sk_buff *skb)
+{
+	int rc = -ENOBUFS;
+	struct llc_sock *llc = llc_sk(sk);
+	struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_S, 0);
+
+	if (nskb) {
+		struct llc_sap *sap = llc->sap;
+
+		llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
+				    llc->daddr.lsap, LLC_PDU_RSP);
+		llc_pdu_init_as_rr_rsp(nskb, 1, llc->vR);
+		rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
+		if (unlikely(rc))
+			goto free;
+		llc_conn_send_pdu(sk, nskb);
+	}
+out:
+	return rc;
+free:
+	kfree_skb(nskb);
+	goto out;
+}
+
+int llc_conn_ac_send_rr_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
+{
+	int rc = -ENOBUFS;
+	struct llc_sock *llc = llc_sk(sk);
+	struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_S, 0);
+
+	if (nskb) {
+		struct llc_sap *sap = llc->sap;
+
+		llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
+				    llc->daddr.lsap, LLC_PDU_RSP);
+		llc_pdu_init_as_rr_rsp(nskb, 0, llc->vR);
+		rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
+		if (unlikely(rc))
+			goto free;
+		llc_conn_send_pdu(sk, nskb);
+	}
+out:
+	return rc;
+free:
+	kfree_skb(nskb);
+	goto out;
+}
+
+int llc_conn_ac_send_ack_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
+{
+	int rc = -ENOBUFS;
+	struct llc_sock *llc = llc_sk(sk);
+	struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_S, 0);
+
+	if (nskb) {
+		struct llc_sap *sap = llc->sap;
+
+		llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
+				    llc->daddr.lsap, LLC_PDU_RSP);
+		llc_pdu_init_as_rr_rsp(nskb, 0, llc->vR);
+		rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
+		if (unlikely(rc))
+			goto free;
+		llc_conn_send_pdu(sk, nskb);
+	}
+out:
+	return rc;
+free:
+	kfree_skb(nskb);
+	goto out;
+}
+
+void llc_conn_set_p_flag(struct sock *sk, u8 value)
+{
+	int state_changed = llc_sk(sk)->p_flag && !value;
+
+	llc_sk(sk)->p_flag = value;
+
+	if (state_changed)
+		sk->sk_state_change(sk);
+}
+
+int llc_conn_ac_send_sabme_cmd_p_set_x(struct sock *sk, struct sk_buff *skb)
+{
+	int rc = -ENOBUFS;
+	struct llc_sock *llc = llc_sk(sk);
+	struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_U, 0);
+
+	if (nskb) {
+		struct llc_sap *sap = llc->sap;
+		u8 *dmac = llc->daddr.mac;
+
+		if (llc->dev->flags & IFF_LOOPBACK)
+			dmac = llc->dev->dev_addr;
+		llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
+				    llc->daddr.lsap, LLC_PDU_CMD);
+		llc_pdu_init_as_sabme_cmd(nskb, 1);
+		rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, dmac);
+		if (unlikely(rc))
+			goto free;
+		llc_conn_send_pdu(sk, nskb);
+		llc_conn_set_p_flag(sk, 1);
+	}
+out:
+	return rc;
+free:
+	kfree_skb(nskb);
+	goto out;
+}
+
+int llc_conn_ac_send_ua_rsp_f_set_p(struct sock *sk, struct sk_buff *skb)
+{
+	u8 f_bit;
+	int rc = -ENOBUFS;
+	struct llc_sock *llc = llc_sk(sk);
+	struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_U, 0);
+
+	llc_pdu_decode_pf_bit(skb, &f_bit);
+	if (nskb) {
+		struct llc_sap *sap = llc->sap;
+
+		nskb->dev = llc->dev;
+		llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
+				    llc->daddr.lsap, LLC_PDU_RSP);
+		llc_pdu_init_as_ua_rsp(nskb, f_bit);
+		rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
+		if (unlikely(rc))
+			goto free;
+		llc_conn_send_pdu(sk, nskb);
+	}
+out:
+	return rc;
+free:
+	kfree_skb(nskb);
+	goto out;
+}
+
+int llc_conn_ac_set_s_flag_0(struct sock *sk, struct sk_buff *skb)
+{
+	llc_sk(sk)->s_flag = 0;
+	return 0;
+}
+
+int llc_conn_ac_set_s_flag_1(struct sock *sk, struct sk_buff *skb)
+{
+	llc_sk(sk)->s_flag = 1;
+	return 0;
+}
+
+int llc_conn_ac_start_p_timer(struct sock *sk, struct sk_buff *skb)
+{
+	struct llc_sock *llc = llc_sk(sk);
+
+	llc_conn_set_p_flag(sk, 1);
+	mod_timer(&llc->pf_cycle_timer.timer,
+		  jiffies + llc->pf_cycle_timer.expire);
+	return 0;
+}
+
+/**
+ *	llc_conn_ac_send_ack_if_needed - check if ack is needed
+ *	@sk: current connection structure
+ *	@skb: current event
+ *
+ *	Checks number of received PDUs which have not been acknowledged, yet,
+ *	If number of them reaches to "npta"(Number of PDUs To Acknowledge) then
+ *	sends an RR response as acknowledgement for them.  Returns 0 for
+ *	success, 1 otherwise.
+ */
+int llc_conn_ac_send_ack_if_needed(struct sock *sk, struct sk_buff *skb)
+{
+	u8 pf_bit;
+	struct llc_sock *llc = llc_sk(sk);
+
+	llc_pdu_decode_pf_bit(skb, &pf_bit);
+	llc->ack_pf |= pf_bit & 1;
+	if (!llc->ack_must_be_send) {
+		llc->first_pdu_Ns = llc->vR;
+		llc->ack_must_be_send = 1;
+		llc->ack_pf = pf_bit & 1;
+	}
+	if (((llc->vR - llc->first_pdu_Ns + 1 + LLC_2_SEQ_NBR_MODULO)
+			% LLC_2_SEQ_NBR_MODULO) >= llc->npta) {
+		llc_conn_ac_send_rr_rsp_f_set_ackpf(sk, skb);
+		llc->ack_must_be_send	= 0;
+		llc->ack_pf		= 0;
+		llc_conn_ac_inc_npta_value(sk, skb);
+	}
+	return 0;
+}
+
+/**
+ *	llc_conn_ac_rst_sendack_flag - resets ack_must_be_send flag
+ *	@sk: current connection structure
+ *	@skb: current event
+ *
+ *	This action resets ack_must_be_send flag of given connection, this flag
+ *	indicates if there is any PDU which has not been acknowledged yet.
+ *	Returns 0 for success, 1 otherwise.
+ */
+int llc_conn_ac_rst_sendack_flag(struct sock *sk, struct sk_buff *skb)
+{
+	llc_sk(sk)->ack_must_be_send = llc_sk(sk)->ack_pf = 0;
+	return 0;
+}
+
+/**
+ *	llc_conn_ac_send_i_rsp_f_set_ackpf - acknowledge received PDUs
+ *	@sk: current connection structure
+ *	@skb: current event
+ *
+ *	Sends an I response PDU with f-bit set to ack_pf flag as acknowledge to
+ *	all received PDUs which have not been acknowledged, yet. ack_pf flag is
+ *	set to one if one PDU with p-bit set to one is received.  Returns 0 for
+ *	success, 1 otherwise.
+ */
+static int llc_conn_ac_send_i_rsp_f_set_ackpf(struct sock *sk,
+					      struct sk_buff *skb)
+{
+	int rc;
+	struct llc_sock *llc = llc_sk(sk);
+	struct llc_sap *sap = llc->sap;
+
+	llc_pdu_header_init(skb, LLC_PDU_TYPE_I, sap->laddr.lsap,
+			    llc->daddr.lsap, LLC_PDU_RSP);
+	llc_pdu_init_as_i_cmd(skb, llc->ack_pf, llc->vS, llc->vR);
+	rc = llc_mac_hdr_init(skb, llc->dev->dev_addr, llc->daddr.mac);
+	if (likely(!rc)) {
+		skb_get(skb);
+		llc_conn_send_pdu(sk, skb);
+		llc_conn_ac_inc_vs_by_1(sk, skb);
+	}
+	return rc;
+}
+
+/**
+ *	llc_conn_ac_send_i_as_ack - sends an I-format PDU to acknowledge rx PDUs
+ *	@sk: current connection structure.
+ *	@skb: current event.
+ *
+ *	This action sends an I-format PDU as acknowledge to received PDUs which
+ *	have not been acknowledged, yet, if there is any. By using of this
+ *	action number of acknowledgements decreases, this technic is called
+ *	piggy backing. Returns 0 for success, 1 otherwise.
+ */
+int llc_conn_ac_send_i_as_ack(struct sock *sk, struct sk_buff *skb)
+{
+	struct llc_sock *llc = llc_sk(sk);
+	int ret;
+
+	if (llc->ack_must_be_send) {
+		ret = llc_conn_ac_send_i_rsp_f_set_ackpf(sk, skb);
+		llc->ack_must_be_send = 0 ;
+		llc->ack_pf = 0;
+	} else {
+		ret = llc_conn_ac_send_i_cmd_p_set_0(sk, skb);
+	}
+
+	return ret;
+}
+
+/**
+ *	llc_conn_ac_send_rr_rsp_f_set_ackpf - ack all rx PDUs not yet acked
+ *	@sk: current connection structure.
+ *	@skb: current event.
+ *
+ *	This action sends an RR response with f-bit set to ack_pf flag as
+ *	acknowledge to all received PDUs which have not been acknowledged, yet,
+ *	if there is any. ack_pf flag indicates if a PDU has been received with
+ *	p-bit set to one. Returns 0 for success, 1 otherwise.
+ */
+static int llc_conn_ac_send_rr_rsp_f_set_ackpf(struct sock *sk,
+					       struct sk_buff *skb)
+{
+	int rc = -ENOBUFS;
+	struct llc_sock *llc = llc_sk(sk);
+	struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_S, 0);
+
+	if (nskb) {
+		struct llc_sap *sap = llc->sap;
+
+		llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
+				    llc->daddr.lsap, LLC_PDU_RSP);
+		llc_pdu_init_as_rr_rsp(nskb, llc->ack_pf, llc->vR);
+		rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
+		if (unlikely(rc))
+			goto free;
+		llc_conn_send_pdu(sk, nskb);
+	}
+out:
+	return rc;
+free:
+	kfree_skb(nskb);
+	goto out;
+}
+
+/**
+ *	llc_conn_ac_inc_npta_value - tries to make value of npta greater
+ *	@sk: current connection structure.
+ *	@skb: current event.
+ *
+ *	After "inc_cntr" times calling of this action, "npta" increase by one.
+ *	this action tries to make vale of "npta" greater as possible; number of
+ *	acknowledgements decreases by increasing of "npta". Returns 0 for
+ *	success, 1 otherwise.
+ */
+static int llc_conn_ac_inc_npta_value(struct sock *sk, struct sk_buff *skb)
+{
+	struct llc_sock *llc = llc_sk(sk);
+
+	if (!llc->inc_cntr) {
+		llc->dec_step = 0;
+		llc->dec_cntr = llc->inc_cntr = 2;
+		++llc->npta;
+		if (llc->npta > (u8) ~LLC_2_SEQ_NBR_MODULO)
+			llc->npta = (u8) ~LLC_2_SEQ_NBR_MODULO;
+	} else
+		--llc->inc_cntr;
+	return 0;
+}
+
+/**
+ *	llc_conn_ac_adjust_npta_by_rr - decreases "npta" by one
+ *	@sk: current connection structure.
+ *	@skb: current event.
+ *
+ *	After receiving "dec_cntr" times RR command, this action decreases
+ *	"npta" by one. Returns 0 for success, 1 otherwise.
+ */
+int llc_conn_ac_adjust_npta_by_rr(struct sock *sk, struct sk_buff *skb)
+{
+	struct llc_sock *llc = llc_sk(sk);
+
+	if (!llc->connect_step && !llc->remote_busy_flag) {
+		if (!llc->dec_step) {
+			if (!llc->dec_cntr) {
+				llc->inc_cntr = llc->dec_cntr = 2;
+				if (llc->npta > 0)
+					llc->npta = llc->npta - 1;
+			} else
+				llc->dec_cntr -=1;
+		}
+	} else
+		llc->connect_step = 0 ;
+	return 0;
+}
+
+/**
+ *	llc_conn_ac_adjust_npta_by_rnr - decreases "npta" by one
+ *	@sk: current connection structure.
+ *	@skb: current event.
+ *
+ *	After receiving "dec_cntr" times RNR command, this action decreases
+ *	"npta" by one. Returns 0 for success, 1 otherwise.
+ */
+int llc_conn_ac_adjust_npta_by_rnr(struct sock *sk, struct sk_buff *skb)
+{
+	struct llc_sock *llc = llc_sk(sk);
+
+	if (llc->remote_busy_flag)
+		if (!llc->dec_step) {
+			if (!llc->dec_cntr) {
+				llc->inc_cntr = llc->dec_cntr = 2;
+				if (llc->npta > 0)
+					--llc->npta;
+			} else
+				--llc->dec_cntr;
+		}
+	return 0;
+}
+
+/**
+ *	llc_conn_ac_dec_tx_win_size - decreases tx window size
+ *	@sk: current connection structure.
+ *	@skb: current event.
+ *
+ *	After receiving of a REJ command or response, transmit window size is
+ *	decreased by number of PDUs which are outstanding yet. Returns 0 for
+ *	success, 1 otherwise.
+ */
+int llc_conn_ac_dec_tx_win_size(struct sock *sk, struct sk_buff *skb)
+{
+	struct llc_sock *llc = llc_sk(sk);
+	u8 unacked_pdu = skb_queue_len(&llc->pdu_unack_q);
+
+	if (llc->k - unacked_pdu < 1)
+		llc->k = 1;
+	else
+		llc->k -= unacked_pdu;
+	return 0;
+}
+
+/**
+ *	llc_conn_ac_inc_tx_win_size - tx window size is inc by 1
+ *	@sk: current connection structure.
+ *	@skb: current event.
+ *
+ *	After receiving an RR response with f-bit set to one, transmit window
+ *	size is increased by one. Returns 0 for success, 1 otherwise.
+ */
+int llc_conn_ac_inc_tx_win_size(struct sock *sk, struct sk_buff *skb)
+{
+	struct llc_sock *llc = llc_sk(sk);
+
+	llc->k += 1;
+	if (llc->k > (u8) ~LLC_2_SEQ_NBR_MODULO)
+		llc->k = (u8) ~LLC_2_SEQ_NBR_MODULO;
+	return 0;
+}
+
+int llc_conn_ac_stop_all_timers(struct sock *sk, struct sk_buff *skb)
+{
+	llc_sk_stop_all_timers(sk, false);
+	return 0;
+}
+
+int llc_conn_ac_stop_other_timers(struct sock *sk, struct sk_buff *skb)
+{
+	struct llc_sock *llc = llc_sk(sk);
+
+	del_timer(&llc->rej_sent_timer.timer);
+	del_timer(&llc->pf_cycle_timer.timer);
+	del_timer(&llc->busy_state_timer.timer);
+	llc->ack_must_be_send = 0;
+	llc->ack_pf = 0;
+	return 0;
+}
+
+int llc_conn_ac_start_ack_timer(struct sock *sk, struct sk_buff *skb)
+{
+	struct llc_sock *llc = llc_sk(sk);
+
+	mod_timer(&llc->ack_timer.timer, jiffies + llc->ack_timer.expire);
+	return 0;
+}
+
+int llc_conn_ac_start_rej_timer(struct sock *sk, struct sk_buff *skb)
+{
+	struct llc_sock *llc = llc_sk(sk);
+
+	mod_timer(&llc->rej_sent_timer.timer,
+		  jiffies + llc->rej_sent_timer.expire);
+	return 0;
+}
+
+int llc_conn_ac_start_ack_tmr_if_not_running(struct sock *sk,
+					     struct sk_buff *skb)
+{
+	struct llc_sock *llc = llc_sk(sk);
+
+	if (!timer_pending(&llc->ack_timer.timer))
+		mod_timer(&llc->ack_timer.timer,
+			  jiffies + llc->ack_timer.expire);
+	return 0;
+}
+
+int llc_conn_ac_stop_ack_timer(struct sock *sk, struct sk_buff *skb)
+{
+	del_timer(&llc_sk(sk)->ack_timer.timer);
+	return 0;
+}
+
+int llc_conn_ac_stop_p_timer(struct sock *sk, struct sk_buff *skb)
+{
+	struct llc_sock *llc = llc_sk(sk);
+
+	del_timer(&llc->pf_cycle_timer.timer);
+	llc_conn_set_p_flag(sk, 0);
+	return 0;
+}
+
+int llc_conn_ac_stop_rej_timer(struct sock *sk, struct sk_buff *skb)
+{
+	del_timer(&llc_sk(sk)->rej_sent_timer.timer);
+	return 0;
+}
+
+int llc_conn_ac_upd_nr_received(struct sock *sk, struct sk_buff *skb)
+{
+	int acked;
+	u16 unacked = 0;
+	struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
+	struct llc_sock *llc = llc_sk(sk);
+
+	llc->last_nr = PDU_SUPV_GET_Nr(pdu);
+	acked = llc_conn_remove_acked_pdus(sk, llc->last_nr, &unacked);
+	/* On loopback we don't queue I frames in unack_pdu_q queue. */
+	if (acked > 0 || (llc->dev->flags & IFF_LOOPBACK)) {
+		llc->retry_count = 0;
+		del_timer(&llc->ack_timer.timer);
+		if (llc->failed_data_req) {
+			/* already, we did not accept data from upper layer
+			 * (tx_window full or unacceptable state). Now, we
+			 * can send data and must inform to upper layer.
+			 */
+			llc->failed_data_req = 0;
+			llc_conn_ac_data_confirm(sk, skb);
+		}
+		if (unacked)
+			mod_timer(&llc->ack_timer.timer,
+				  jiffies + llc->ack_timer.expire);
+	} else if (llc->failed_data_req) {
+		u8 f_bit;
+
+		llc_pdu_decode_pf_bit(skb, &f_bit);
+		if (f_bit == 1) {
+			llc->failed_data_req = 0;
+			llc_conn_ac_data_confirm(sk, skb);
+		}
+	}
+	return 0;
+}
+
+int llc_conn_ac_upd_p_flag(struct sock *sk, struct sk_buff *skb)
+{
+	struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
+
+	if (LLC_PDU_IS_RSP(pdu)) {
+		u8 f_bit;
+
+		llc_pdu_decode_pf_bit(skb, &f_bit);
+		if (f_bit) {
+			llc_conn_set_p_flag(sk, 0);
+			llc_conn_ac_stop_p_timer(sk, skb);
+		}
+	}
+	return 0;
+}
+
+int llc_conn_ac_set_data_flag_2(struct sock *sk, struct sk_buff *skb)
+{
+	llc_sk(sk)->data_flag = 2;
+	return 0;
+}
+
+int llc_conn_ac_set_data_flag_0(struct sock *sk, struct sk_buff *skb)
+{
+	llc_sk(sk)->data_flag = 0;
+	return 0;
+}
+
+int llc_conn_ac_set_data_flag_1(struct sock *sk, struct sk_buff *skb)
+{
+	llc_sk(sk)->data_flag = 1;
+	return 0;
+}
+
+int llc_conn_ac_set_data_flag_1_if_data_flag_eq_0(struct sock *sk,
+						  struct sk_buff *skb)
+{
+	if (!llc_sk(sk)->data_flag)
+		llc_sk(sk)->data_flag = 1;
+	return 0;
+}
+
+int llc_conn_ac_set_p_flag_0(struct sock *sk, struct sk_buff *skb)
+{
+	llc_conn_set_p_flag(sk, 0);
+	return 0;
+}
+
+static int llc_conn_ac_set_p_flag_1(struct sock *sk, struct sk_buff *skb)
+{
+	llc_conn_set_p_flag(sk, 1);
+	return 0;
+}
+
+int llc_conn_ac_set_remote_busy_0(struct sock *sk, struct sk_buff *skb)
+{
+	llc_sk(sk)->remote_busy_flag = 0;
+	return 0;
+}
+
+int llc_conn_ac_set_cause_flag_0(struct sock *sk, struct sk_buff *skb)
+{
+	llc_sk(sk)->cause_flag = 0;
+	return 0;
+}
+
+int llc_conn_ac_set_cause_flag_1(struct sock *sk, struct sk_buff *skb)
+{
+	llc_sk(sk)->cause_flag = 1;
+	return 0;
+}
+
+int llc_conn_ac_set_retry_cnt_0(struct sock *sk, struct sk_buff *skb)
+{
+	llc_sk(sk)->retry_count = 0;
+	return 0;
+}
+
+int llc_conn_ac_inc_retry_cnt_by_1(struct sock *sk, struct sk_buff *skb)
+{
+	llc_sk(sk)->retry_count++;
+	return 0;
+}
+
+int llc_conn_ac_set_vr_0(struct sock *sk, struct sk_buff *skb)
+{
+	llc_sk(sk)->vR = 0;
+	return 0;
+}
+
+int llc_conn_ac_inc_vr_by_1(struct sock *sk, struct sk_buff *skb)
+{
+	llc_sk(sk)->vR = PDU_GET_NEXT_Vr(llc_sk(sk)->vR);
+	return 0;
+}
+
+int llc_conn_ac_set_vs_0(struct sock *sk, struct sk_buff *skb)
+{
+	llc_sk(sk)->vS = 0;
+	return 0;
+}
+
+int llc_conn_ac_set_vs_nr(struct sock *sk, struct sk_buff *skb)
+{
+	llc_sk(sk)->vS = llc_sk(sk)->last_nr;
+	return 0;
+}
+
+static int llc_conn_ac_inc_vs_by_1(struct sock *sk, struct sk_buff *skb)
+{
+	llc_sk(sk)->vS = (llc_sk(sk)->vS + 1) % LLC_2_SEQ_NBR_MODULO;
+	return 0;
+}
+
+static void llc_conn_tmr_common_cb(struct sock *sk, u8 type)
+{
+	struct sk_buff *skb = alloc_skb(0, GFP_ATOMIC);
+
+	bh_lock_sock(sk);
+	if (skb) {
+		struct llc_conn_state_ev *ev = llc_conn_ev(skb);
+
+		skb_set_owner_r(skb, sk);
+		ev->type = type;
+		llc_process_tmr_ev(sk, skb);
+	}
+	bh_unlock_sock(sk);
+}
+
+void llc_conn_pf_cycle_tmr_cb(struct timer_list *t)
+{
+	struct llc_sock *llc = from_timer(llc, t, pf_cycle_timer.timer);
+
+	llc_conn_tmr_common_cb(&llc->sk, LLC_CONN_EV_TYPE_P_TMR);
+}
+
+void llc_conn_busy_tmr_cb(struct timer_list *t)
+{
+	struct llc_sock *llc = from_timer(llc, t, busy_state_timer.timer);
+
+	llc_conn_tmr_common_cb(&llc->sk, LLC_CONN_EV_TYPE_BUSY_TMR);
+}
+
+void llc_conn_ack_tmr_cb(struct timer_list *t)
+{
+	struct llc_sock *llc = from_timer(llc, t, ack_timer.timer);
+
+	llc_conn_tmr_common_cb(&llc->sk, LLC_CONN_EV_TYPE_ACK_TMR);
+}
+
+void llc_conn_rej_tmr_cb(struct timer_list *t)
+{
+	struct llc_sock *llc = from_timer(llc, t, rej_sent_timer.timer);
+
+	llc_conn_tmr_common_cb(&llc->sk, LLC_CONN_EV_TYPE_REJ_TMR);
+}
+
+int llc_conn_ac_rst_vs(struct sock *sk, struct sk_buff *skb)
+{
+	llc_sk(sk)->X = llc_sk(sk)->vS;
+	llc_conn_ac_set_vs_nr(sk, skb);
+	return 0;
+}
+
+int llc_conn_ac_upd_vs(struct sock *sk, struct sk_buff *skb)
+{
+	struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
+	u8 nr = PDU_SUPV_GET_Nr(pdu);
+
+	if (llc_circular_between(llc_sk(sk)->vS, nr, llc_sk(sk)->X))
+		llc_conn_ac_set_vs_nr(sk, skb);
+	return 0;
+}
+
+/*
+ * Non-standard actions; these not contained in IEEE specification; for
+ * our own usage
+ */
+/**
+ *	llc_conn_disc - removes connection from SAP list and frees it
+ *	@sk: closed connection
+ *	@skb: occurred event
+ */
+int llc_conn_disc(struct sock *sk, struct sk_buff *skb)
+{
+	/* FIXME: this thing seems to want to die */
+	return 0;
+}
+
+/**
+ *	llc_conn_reset - resets connection
+ *	@sk : reseting connection.
+ *	@skb: occurred event.
+ *
+ *	Stop all timers, empty all queues and reset all flags.
+ */
+int llc_conn_reset(struct sock *sk, struct sk_buff *skb)
+{
+	llc_sk_reset(sk);
+	return 0;
+}
+
+/**
+ *	llc_circular_between - designates that b is between a and c or not
+ *	@a: lower bound
+ *	@b: element to see if is between a and b
+ *	@c: upper bound
+ *
+ *	This function designates that b is between a and c or not (for example,
+ *	0 is between 127 and 1). Returns 1 if b is between a and c, 0
+ *	otherwise.
+ */
+u8 llc_circular_between(u8 a, u8 b, u8 c)
+{
+	b = b - a;
+	c = c - a;
+	return b <= c;
+}
+
+/**
+ *	llc_process_tmr_ev - timer backend
+ *	@sk: active connection
+ *	@skb: occurred event
+ *
+ *	This function is called from timer callback functions. When connection
+ *	is busy (during sending a data frame) timer expiration event must be
+ *	queued. Otherwise this event can be sent to connection state machine.
+ *	Queued events will process by llc_backlog_rcv function after sending
+ *	data frame.
+ */
+static void llc_process_tmr_ev(struct sock *sk, struct sk_buff *skb)
+{
+	if (llc_sk(sk)->state == LLC_CONN_OUT_OF_SVC) {
+		printk(KERN_WARNING "%s: timer called on closed connection\n",
+		       __func__);
+		kfree_skb(skb);
+	} else {
+		if (!sock_owned_by_user(sk))
+			llc_conn_state_process(sk, skb);
+		else {
+			llc_set_backlog_type(skb, LLC_EVENT);
+			__sk_add_backlog(sk, skb);
+		}
+	}
+}