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
18 extern void dn_nsp_send_data_ack(struct sock *sk);
19 extern void dn_nsp_send_oth_ack(struct sock *sk);
20 extern void dn_nsp_delayed_ack(struct sock *sk);
21 extern void dn_send_conn_ack(struct sock *sk);
22 extern void dn_send_conn_conf(struct sock *sk, int gfp);
23 extern void dn_nsp_send_disc(struct sock *sk, unsigned char type,
24 unsigned short reason, int gfp);
25 extern void dn_nsp_return_disc(struct sk_buff *skb, unsigned char type,
26 unsigned short reason);
27 extern void dn_nsp_send_link(struct sock *sk, unsigned char lsflags, char fcval);
28 extern void dn_nsp_send_conninit(struct sock *sk, unsigned char flags);
29
30 extern void dn_nsp_output(struct sock *sk);
31 extern int dn_nsp_check_xmit_queue(struct sock *sk, struct sk_buff *skb, struct sk_buff_head *q, unsigned short acknum);
32 extern void dn_nsp_queue_xmit(struct sock *sk, struct sk_buff *skb, int gfp, int oob);
33 extern unsigned long dn_nsp_persist(struct sock *sk);
34 extern int dn_nsp_xmit_timeout(struct sock *sk);
35
36 extern int dn_nsp_rx(struct sk_buff *);
37 extern int dn_nsp_backlog_rcv(struct sock *sk, struct sk_buff *skb);
38
39 extern struct sk_buff *dn_alloc_skb(struct sock *sk, int size, int pri);
40 extern struct sk_buff *dn_alloc_send_skb(struct sock *sk, int *size, int noblock, 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
73 struct nsp_data_seg_msg
74 {
75 unsigned char msgflg;
76 unsigned short dstaddr;
77 unsigned short srcaddr;
78 };
79
80 struct nsp_data_opt_msg
81 {
82 unsigned short acknum __attribute__((packed));
83 unsigned short segnum __attribute__((packed));
84 unsigned short lsflgs __attribute__((packed));
85 };
86
87 struct nsp_data_opt_msg1
88 {
89 unsigned short acknum __attribute__((packed));
90 unsigned short segnum __attribute__((packed));
91 };
92
93
94 /* Acknowledgment Message (data/other data) */
95 struct nsp_data_ack_msg
96 {
97 unsigned char msgflg;
98 unsigned short dstaddr __attribute__((packed));
99 unsigned short srcaddr __attribute__((packed));
100 unsigned short acknum __attribute__((packed));
101 };
102
103 /* Connect Acknowledgment Message */
104 struct nsp_conn_ack_msg
105 {
106 unsigned char msgflg;
107 unsigned short dstaddr __attribute__((packed));
108 };
109
110
111 /* Connect Initiate/Retransmit Initiate/Connect Confirm */
112 struct nsp_conn_init_msg
113 {
114 unsigned char msgflg;
115 #define NSP_CI 0x18 /* Connect Initiate */
116 #define NSP_RCI 0x68 /* Retrans. Conn Init */
117 unsigned short dstaddr __attribute__((packed));
118 unsigned short srcaddr __attribute__((packed));
119 unsigned char 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 unsigned char info;
125 unsigned short segsize __attribute__((packed));
126 };
127
128 /* Disconnect Initiate/Disconnect Confirm */
129 struct nsp_disconn_init_msg
130 {
131 unsigned char msgflg;
132 unsigned short dstaddr __attribute__((packed));
133 unsigned short srcaddr __attribute__((packed));
134 unsigned short reason __attribute__((packed));
135 };
136
137
138
139 struct srcobj_fmt
140 {
141 char format;
142 unsigned char task;
143 unsigned short grpcode __attribute__((packed));
144 unsigned short usrcode __attribute__((packed));
145 char dlen;
146 };
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 */
before(unsigned short seq1,unsigned short seq2)153 static __inline__ int before(unsigned short seq1, unsigned short seq2)
154 {
155 seq1 &= 0x0fff;
156 seq2 &= 0x0fff;
157
158 return (int)((seq1 - seq2) & 0x0fff) > 2048;
159 }
160
161
after(unsigned short seq1,unsigned short seq2)162 static __inline__ int after(unsigned short seq1, unsigned short seq2)
163 {
164 seq1 &= 0x0fff;
165 seq2 &= 0x0fff;
166
167 return (int)((seq2 - seq1) & 0x0fff) > 2048;
168 }
169
equal(unsigned short seq1,unsigned short seq2)170 static __inline__ int equal(unsigned short seq1, unsigned short seq2)
171 {
172 return ((seq1 ^ seq2) & 0x0fff) == 0;
173 }
174
before_or_equal(unsigned short seq1,unsigned short seq2)175 static __inline__ int before_or_equal(unsigned short seq1, unsigned short seq2)
176 {
177 return (before(seq1, seq2) || equal(seq1, seq2));
178 }
179
seq_add(unsigned short * seq,unsigned short off)180 static __inline__ void seq_add(unsigned short *seq, unsigned short off)
181 {
182 (*seq) += off;
183 (*seq) &= 0x0fff;
184 }
185
seq_next(unsigned short seq1,unsigned short seq2)186 static __inline__ int seq_next(unsigned short seq1, unsigned short seq2)
187 {
188 return equal(seq1 + 1, seq2);
189 }
190
191 /*
192 * Can we delay the ack ?
193 */
sendack(unsigned short seq)194 static __inline__ int sendack(unsigned short seq)
195 {
196 return (int)((seq & 0x1000) ? 0 : 1);
197 }
198
199 /*
200 * Is socket congested ?
201 */
dn_congested(struct sock * sk)202 static __inline__ int dn_congested(struct sock *sk)
203 {
204 return atomic_read(&sk->rmem_alloc) > (sk->rcvbuf >> 1);
205 }
206
207 #endif /* _NET_DN_NSP_H */
208