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, gfp_t gfp);
23 extern void dn_nsp_send_disc(struct sock *sk, unsigned char type,
24 			unsigned short reason, gfp_t 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, gfp_t 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, gfp_t pri);
40 extern 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 
73 struct nsp_data_seg_msg {
74 	__u8   msgflg;
75 	__le16 dstaddr;
76 	__le16 srcaddr;
77 } __packed;
78 
79 struct nsp_data_opt_msg {
80 	__le16 acknum;
81 	__le16 segnum;
82 	__le16 lsflgs;
83 } __packed;
84 
85 struct nsp_data_opt_msg1 {
86 	__le16 acknum;
87 	__le16 segnum;
88 } __packed;
89 
90 
91 /* Acknowledgment Message (data/other data)                             */
92 struct nsp_data_ack_msg {
93 	__u8   msgflg;
94 	__le16 dstaddr;
95 	__le16 srcaddr;
96 	__le16 acknum;
97 } __packed;
98 
99 /* Connect Acknowledgment Message */
100 struct  nsp_conn_ack_msg {
101 	__u8 msgflg;
102 	__le16 dstaddr;
103 } __packed;
104 
105 
106 /* Connect Initiate/Retransmit Initiate/Connect Confirm */
107 struct  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 */
123 struct  nsp_disconn_init_msg {
124 	__u8   msgflg;
125 	__le16 dstaddr;
126 	__le16 srcaddr;
127 	__le16 reason;
128 } __packed;
129 
130 
131 
132 struct  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  */
dn_before(__u16 seq1,__u16 seq2)145 static __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 
dn_after(__u16 seq1,__u16 seq2)154 static __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 
dn_equal(__u16 seq1,__u16 seq2)162 static __inline__ int dn_equal(__u16 seq1, __u16 seq2)
163 {
164         return ((seq1 ^ seq2) & 0x0fff) == 0;
165 }
166 
dn_before_or_equal(__u16 seq1,__u16 seq2)167 static __inline__ int dn_before_or_equal(__u16 seq1, __u16 seq2)
168 {
169 	return (dn_before(seq1, seq2) || dn_equal(seq1, seq2));
170 }
171 
seq_add(__u16 * seq,__u16 off)172 static __inline__ void seq_add(__u16 *seq, __u16 off)
173 {
174         (*seq) += off;
175         (*seq) &= 0x0fff;
176 }
177 
seq_next(__u16 seq1,__u16 seq2)178 static __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  */
sendack(__u16 seq)186 static __inline__ int sendack(__u16 seq)
187 {
188         return (int)((seq & 0x1000) ? 0 : 1);
189 }
190 
191 /*
192  * Is socket congested ?
193  */
dn_congested(struct sock * sk)194 static __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 */
202