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
 18void dn_nsp_send_data_ack(struct sock *sk);
 19void dn_nsp_send_oth_ack(struct sock *sk);
 20void dn_nsp_delayed_ack(struct sock *sk);
 21void dn_send_conn_ack(struct sock *sk);
 22void dn_send_conn_conf(struct sock *sk, gfp_t gfp);
 23void dn_nsp_send_disc(struct sock *sk, unsigned char type,
 24		      unsigned short reason, gfp_t gfp);
 25void dn_nsp_return_disc(struct sk_buff *skb, unsigned char type,
 26			unsigned short reason);
 27void dn_nsp_send_link(struct sock *sk, unsigned char lsflags, char fcval);
 28void dn_nsp_send_conninit(struct sock *sk, unsigned char flags);
 29
 30void dn_nsp_output(struct sock *sk);
 31int dn_nsp_check_xmit_queue(struct sock *sk, struct sk_buff *skb,
 32			    struct sk_buff_head *q, unsigned short acknum);
 33void dn_nsp_queue_xmit(struct sock *sk, struct sk_buff *skb, gfp_t gfp,
 34		       int oob);
 35unsigned long dn_nsp_persist(struct sock *sk);
 36int dn_nsp_xmit_timeout(struct sock *sk);
 37
 38int dn_nsp_rx(struct sk_buff *);
 39int dn_nsp_backlog_rcv(struct sock *sk, struct sk_buff *skb);
 40
 41struct sk_buff *dn_alloc_skb(struct sock *sk, int size, gfp_t pri);
 42struct sk_buff *dn_alloc_send_skb(struct sock *sk, size_t *size, int noblock,
 43				  long timeo, int *err);
 44
 45#define NSP_REASON_OK 0		/* No error */
 46#define NSP_REASON_NR 1		/* No resources */
 47#define NSP_REASON_UN 2		/* Unrecognised node name */
 48#define NSP_REASON_SD 3		/* Node shutting down */
 49#define NSP_REASON_ID 4		/* Invalid destination end user */
 50#define NSP_REASON_ER 5		/* End user lacks resources */
 51#define NSP_REASON_OB 6		/* Object too busy */
 52#define NSP_REASON_US 7		/* Unspecified error */
 53#define NSP_REASON_TP 8		/* Third-Party abort */
 54#define NSP_REASON_EA 9		/* End user has aborted the link */
 55#define NSP_REASON_IF 10	/* Invalid node name format */
 56#define NSP_REASON_LS 11	/* Local node shutdown */
 57#define NSP_REASON_LL 32	/* Node lacks logical-link resources */
 58#define NSP_REASON_LE 33	/* End user lacks logical-link resources */
 59#define NSP_REASON_UR 34	/* Unacceptable RQSTRID or PASSWORD field */
 60#define NSP_REASON_UA 36	/* Unacceptable ACCOUNT field */
 61#define NSP_REASON_TM 38	/* End user timed out logical link */
 62#define NSP_REASON_NU 39	/* Node unreachable */
 63#define NSP_REASON_NL 41	/* No-link message */
 64#define NSP_REASON_DC 42	/* Disconnect confirm */
 65#define NSP_REASON_IO 43	/* Image data field overflow */
 66
 67#define NSP_DISCINIT 0x38
 68#define NSP_DISCCONF 0x48
 69
 70/*------------------------- NSP - messages ------------------------------*/
 71/* Data Messages */
 72/*---------------*/
 73
 74/* Data Messages    (data segment/interrupt/link service)               */
 75
 76struct nsp_data_seg_msg {
 77	__u8   msgflg;
 78	__le16 dstaddr;
 79	__le16 srcaddr;
 80} __packed;
 81
 82struct nsp_data_opt_msg {
 83	__le16 acknum;
 84	__le16 segnum;
 85	__le16 lsflgs;
 86} __packed;
 87
 88struct nsp_data_opt_msg1 {
 89	__le16 acknum;
 90	__le16 segnum;
 91} __packed;
 92
 93
 94/* Acknowledgment Message (data/other data)                             */
 95struct nsp_data_ack_msg {
 96	__u8   msgflg;
 97	__le16 dstaddr;
 98	__le16 srcaddr;
 99	__le16 acknum;
100} __packed;
101
102/* Connect Acknowledgment Message */
103struct  nsp_conn_ack_msg {
104	__u8 msgflg;
105	__le16 dstaddr;
106} __packed;
107
108
109/* Connect Initiate/Retransmit Initiate/Connect Confirm */
110struct  nsp_conn_init_msg {
111	__u8   msgflg;
112#define NSP_CI      0x18            /* Connect Initiate     */
113#define NSP_RCI     0x68            /* Retrans. Conn Init   */
114	__le16 dstaddr;
115	__le16 srcaddr;
116	__u8   services;
117#define NSP_FC_NONE   0x00            /* Flow Control None    */
118#define NSP_FC_SRC    0x04            /* Seg Req. Count       */
119#define NSP_FC_SCMC   0x08            /* Sess. Control Mess   */
120#define NSP_FC_MASK   0x0c            /* FC type mask         */
121	__u8   info;
122	__le16 segsize;
123} __packed;
124
125/* Disconnect Initiate/Disconnect Confirm */
126struct  nsp_disconn_init_msg {
127	__u8   msgflg;
128	__le16 dstaddr;
129	__le16 srcaddr;
130	__le16 reason;
131} __packed;
132
133
134
135struct  srcobj_fmt {
136	__u8   format;
137	__u8   task;
138	__le16 grpcode;
139	__le16 usrcode;
140	__u8   dlen;
141} __packed;
142
143/*
144 * A collection of functions for manipulating the sequence
145 * numbers used in NSP. Similar in operation to the functions
146 * of the same name in TCP.
147 */
148static __inline__ int dn_before(__u16 seq1, __u16 seq2)
149{
150        seq1 &= 0x0fff;
151        seq2 &= 0x0fff;
152
153        return (int)((seq1 - seq2) & 0x0fff) > 2048;
154}
155
156
157static __inline__ int dn_after(__u16 seq1, __u16 seq2)
158{
159        seq1 &= 0x0fff;
160        seq2 &= 0x0fff;
161
162        return (int)((seq2 - seq1) & 0x0fff) > 2048;
163}
164
165static __inline__ int dn_equal(__u16 seq1, __u16 seq2)
166{
167        return ((seq1 ^ seq2) & 0x0fff) == 0;
168}
169
170static __inline__ int dn_before_or_equal(__u16 seq1, __u16 seq2)
171{
172	return (dn_before(seq1, seq2) || dn_equal(seq1, seq2));
173}
174
175static __inline__ void seq_add(__u16 *seq, __u16 off)
176{
177        (*seq) += off;
178        (*seq) &= 0x0fff;
179}
180
181static __inline__ int seq_next(__u16 seq1, __u16 seq2)
182{
183	return dn_equal(seq1 + 1, seq2);
184}
185
186/*
187 * Can we delay the ack ?
188 */
189static __inline__ int sendack(__u16 seq)
190{
191        return (int)((seq & 0x1000) ? 0 : 1);
192}
193
194/*
195 * Is socket congested ?
196 */
197static __inline__ int dn_congested(struct sock *sk)
198{
199        return atomic_read(&sk->sk_rmem_alloc) > (sk->sk_rcvbuf >> 1);
200}
201
202#define DN_MAX_NSP_DATA_HEADER (11)
203
204#endif /* _NET_DN_NSP_H */