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