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{
75	__u8   msgflg;
76	__le16 dstaddr;
77	__le16 srcaddr;
78} __attribute__((packed));
79
80struct nsp_data_opt_msg
81{
82	__le16 acknum;
83	__le16 segnum;
84	__le16 lsflgs;
85} __attribute__((packed));
86
87struct nsp_data_opt_msg1
88{
89	__le16 acknum;
90	__le16 segnum;
91} __attribute__((packed));
92
93
94/* Acknowledgment Message (data/other data)                             */
95struct nsp_data_ack_msg
96{
97	__u8   msgflg;
98	__le16 dstaddr;
99	__le16 srcaddr;
100	__le16 acknum;
101} __attribute__((packed));
102
103/* Connect Acknowledgment Message */
104struct  nsp_conn_ack_msg
105{
106	__u8 msgflg;
107	__le16 dstaddr;
108} __attribute__((packed));
109
110
111/* Connect Initiate/Retransmit Initiate/Connect Confirm */
112struct  nsp_conn_init_msg
113{
114	__u8   msgflg;
115#define NSP_CI      0x18            /* Connect Initiate     */
116#define NSP_RCI     0x68            /* Retrans. Conn Init   */
117	__le16 dstaddr;
118	__le16 srcaddr;
119	__u8   services;
120#define NSP_FC_NONE   0x00            /* Flow Control None    */
121#define NSP_FC_SRC    0x04            /* Seg Req. Count       */
122#define NSP_FC_SCMC   0x08            /* Sess. Control Mess   */
123#define NSP_FC_MASK   0x0c            /* FC type mask         */
124	__u8   info;
125	__le16 segsize;
126} __attribute__((packed));
127
128/* Disconnect Initiate/Disconnect Confirm */
129struct  nsp_disconn_init_msg
130{
131	__u8   msgflg;
132	__le16 dstaddr;
133	__le16 srcaddr;
134	__le16 reason;
135} __attribute__((packed));
136
137
138
139struct  srcobj_fmt
140{
141	__u8   format;
142	__u8   task;
143	__le16 grpcode;
144	__le16 usrcode;
145	__u8   dlen;
146} __attribute__((packed));
147
148/*
149 * A collection of functions for manipulating the sequence
150 * numbers used in NSP. Similar in operation to the functions
151 * of the same name in TCP.
152 */
153static __inline__ int dn_before(__u16 seq1, __u16 seq2)
154{
155        seq1 &= 0x0fff;
156        seq2 &= 0x0fff;
157
158        return (int)((seq1 - seq2) & 0x0fff) > 2048;
159}
160
161
162static __inline__ int dn_after(__u16 seq1, __u16 seq2)
163{
164        seq1 &= 0x0fff;
165        seq2 &= 0x0fff;
166
167        return (int)((seq2 - seq1) & 0x0fff) > 2048;
168}
169
170static __inline__ int dn_equal(__u16 seq1, __u16 seq2)
171{
172        return ((seq1 ^ seq2) & 0x0fff) == 0;
173}
174
175static __inline__ int dn_before_or_equal(__u16 seq1, __u16 seq2)
176{
177	return (dn_before(seq1, seq2) || dn_equal(seq1, seq2));
178}
179
180static __inline__ void seq_add(__u16 *seq, __u16 off)
181{
182        (*seq) += off;
183        (*seq) &= 0x0fff;
184}
185
186static __inline__ int seq_next(__u16 seq1, __u16 seq2)
187{
188	return dn_equal(seq1 + 1, seq2);
189}
190
191/*
192 * Can we delay the ack ?
193 */
194static __inline__ int sendack(__u16 seq)
195{
196        return (int)((seq & 0x1000) ? 0 : 1);
197}
198
199/*
200 * Is socket congested ?
201 */
202static __inline__ int dn_congested(struct sock *sk)
203{
204        return atomic_read(&sk->sk_rmem_alloc) > (sk->sk_rcvbuf >> 1);
205}
206
207#define DN_MAX_NSP_DATA_HEADER (11)
208
209#endif /* _NET_DN_NSP_H */
210