1#ifndef _NET_DN_NSP_H
  2#define _NET_DN_NSP_H
  3/******************************************************************************
  4    (c) 1995-1998 E.M. Serrat		emserrat@geocities.com
  5    
  6    This program is free software; you can redistribute it and/or modify
  7    it under the terms of the GNU General Public License as published by
  8    the Free Software Foundation; either version 2 of the License, or
  9    any later version.
 10
 11    This program is distributed in the hope that it will be useful,
 12    but WITHOUT ANY WARRANTY; without even the implied warranty of
 13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 14    GNU General Public License for more details.
 15*******************************************************************************/
 16/* dn_nsp.c functions prototyping */
 17
 18extern void dn_nsp_send_data_ack(struct sock *sk);
 19extern void dn_nsp_send_oth_ack(struct sock *sk);
 20extern void dn_nsp_delayed_ack(struct sock *sk);
 21extern void dn_send_conn_ack(struct sock *sk);
 22extern void dn_send_conn_conf(struct sock *sk, gfp_t gfp);
 23extern void dn_nsp_send_disc(struct sock *sk, unsigned char type, 
 24			unsigned short reason, gfp_t gfp);
 25extern void dn_nsp_return_disc(struct sk_buff *skb, unsigned char type,
 26				unsigned short reason);
 27extern void dn_nsp_send_link(struct sock *sk, unsigned char lsflags, char fcval);
 28extern void dn_nsp_send_conninit(struct sock *sk, unsigned char flags);
 29
 30extern void dn_nsp_output(struct sock *sk);
 31extern int dn_nsp_check_xmit_queue(struct sock *sk, struct sk_buff *skb, struct sk_buff_head *q, unsigned short acknum);
 32extern void dn_nsp_queue_xmit(struct sock *sk, struct sk_buff *skb, gfp_t gfp, int oob);
 33extern unsigned long dn_nsp_persist(struct sock *sk);
 34extern int dn_nsp_xmit_timeout(struct sock *sk);
 35
 36extern int dn_nsp_rx(struct sk_buff *);
 37extern int dn_nsp_backlog_rcv(struct sock *sk, struct sk_buff *skb);
 38
 39extern struct sk_buff *dn_alloc_skb(struct sock *sk, int size, gfp_t pri);
 40extern struct sk_buff *dn_alloc_send_skb(struct sock *sk, size_t *size, int noblock, long timeo, int *err);
 41
 42#define NSP_REASON_OK 0		/* No error */
 43#define NSP_REASON_NR 1		/* No resources */
 44#define NSP_REASON_UN 2		/* Unrecognised node name */
 45#define NSP_REASON_SD 3		/* Node shutting down */
 46#define NSP_REASON_ID 4		/* Invalid destination end user */
 47#define NSP_REASON_ER 5		/* End user lacks resources */
 48#define NSP_REASON_OB 6		/* Object too busy */
 49#define NSP_REASON_US 7		/* Unspecified error */
 50#define NSP_REASON_TP 8		/* Third-Party abort */
 51#define NSP_REASON_EA 9		/* End user has aborted the link */
 52#define NSP_REASON_IF 10	/* Invalid node name format */
 53#define NSP_REASON_LS 11	/* Local node shutdown */
 54#define NSP_REASON_LL 32	/* Node lacks logical-link resources */
 55#define NSP_REASON_LE 33	/* End user lacks logical-link resources */
 56#define NSP_REASON_UR 34	/* Unacceptable RQSTRID or PASSWORD field */
 57#define NSP_REASON_UA 36	/* Unacceptable ACCOUNT field */
 58#define NSP_REASON_TM 38	/* End user timed out logical link */
 59#define NSP_REASON_NU 39	/* Node unreachable */
 60#define NSP_REASON_NL 41	/* No-link message */
 61#define NSP_REASON_DC 42	/* Disconnect confirm */
 62#define NSP_REASON_IO 43	/* Image data field overflow */
 63
 64#define NSP_DISCINIT 0x38
 65#define NSP_DISCCONF 0x48
 66
 67/*------------------------- NSP - messages ------------------------------*/
 68/* Data Messages */
 69/*---------------*/
 70
 71/* Data Messages    (data segment/interrupt/link service)               */
 72
 73struct nsp_data_seg_msg {
 74	__u8   msgflg;
 75	__le16 dstaddr;
 76	__le16 srcaddr;
 77} __packed;
 78
 79struct nsp_data_opt_msg {
 80	__le16 acknum;
 81	__le16 segnum;
 82	__le16 lsflgs;
 83} __packed;
 84
 85struct nsp_data_opt_msg1 {
 86	__le16 acknum;
 87	__le16 segnum;
 88} __packed;
 89
 90
 91/* Acknowledgment Message (data/other data)                             */
 92struct nsp_data_ack_msg {
 93	__u8   msgflg;
 94	__le16 dstaddr;
 95	__le16 srcaddr;
 96	__le16 acknum;
 97} __packed;
 98
 99/* Connect Acknowledgment Message */
100struct  nsp_conn_ack_msg {
101	__u8 msgflg;
102	__le16 dstaddr;
103} __packed;
104
105
106/* Connect Initiate/Retransmit Initiate/Connect Confirm */
107struct  nsp_conn_init_msg {
108	__u8   msgflg;
109#define NSP_CI      0x18            /* Connect Initiate     */
110#define NSP_RCI     0x68            /* Retrans. Conn Init   */
111	__le16 dstaddr;
112	__le16 srcaddr;
113	__u8   services;
114#define NSP_FC_NONE   0x00            /* Flow Control None    */
115#define NSP_FC_SRC    0x04            /* Seg Req. Count       */
116#define NSP_FC_SCMC   0x08            /* Sess. Control Mess   */
117#define NSP_FC_MASK   0x0c            /* FC type mask         */
118	__u8   info;
119	__le16 segsize;
120} __packed;
121
122/* Disconnect Initiate/Disconnect Confirm */
123struct  nsp_disconn_init_msg {
124	__u8   msgflg;
125	__le16 dstaddr;
126	__le16 srcaddr;
127	__le16 reason;
128} __packed;
129
130
131
132struct  srcobj_fmt {
133	__u8   format;
134	__u8   task;
135	__le16 grpcode;
136	__le16 usrcode;
137	__u8   dlen;
138} __packed;
139
140/*
141 * A collection of functions for manipulating the sequence
142 * numbers used in NSP. Similar in operation to the functions
143 * of the same name in TCP.
144 */
145static __inline__ int dn_before(__u16 seq1, __u16 seq2)
146{
147        seq1 &= 0x0fff;
148        seq2 &= 0x0fff;
149
150        return (int)((seq1 - seq2) & 0x0fff) > 2048;
151}
152
153
154static __inline__ int dn_after(__u16 seq1, __u16 seq2)
155{
156        seq1 &= 0x0fff;
157        seq2 &= 0x0fff;
158
159        return (int)((seq2 - seq1) & 0x0fff) > 2048;
160}
161
162static __inline__ int dn_equal(__u16 seq1, __u16 seq2)
163{
164        return ((seq1 ^ seq2) & 0x0fff) == 0;
165}
166
167static __inline__ int dn_before_or_equal(__u16 seq1, __u16 seq2)
168{
169	return (dn_before(seq1, seq2) || dn_equal(seq1, seq2));
170}
171
172static __inline__ void seq_add(__u16 *seq, __u16 off)
173{
174        (*seq) += off;
175        (*seq) &= 0x0fff;
176}
177
178static __inline__ int seq_next(__u16 seq1, __u16 seq2)
179{
180	return dn_equal(seq1 + 1, seq2);
181}
182
183/*
184 * Can we delay the ack ?
185 */
186static __inline__ int sendack(__u16 seq)
187{
188        return (int)((seq & 0x1000) ? 0 : 1);
189}
190
191/*
192 * Is socket congested ?
193 */
194static __inline__ int dn_congested(struct sock *sk)
195{
196        return atomic_read(&sk->sk_rmem_alloc) > (sk->sk_rcvbuf >> 1);
197}
198
199#define DN_MAX_NSP_DATA_HEADER (11)
200
201#endif /* _NET_DN_NSP_H */