1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 #ifndef _NET_DN_NSP_H
3 #define _NET_DN_NSP_H
4 /******************************************************************************
5 (c) 1995-1998 E.M. Serrat emserrat@geocities.com
6
7 *******************************************************************************/
8 /* dn_nsp.c functions prototyping */
9
10 void dn_nsp_send_data_ack(struct sock *sk);
11 void dn_nsp_send_oth_ack(struct sock *sk);
12 void dn_send_conn_ack(struct sock *sk);
13 void dn_send_conn_conf(struct sock *sk, gfp_t gfp);
14 void dn_nsp_send_disc(struct sock *sk, unsigned char type,
15 unsigned short reason, gfp_t gfp);
16 void dn_nsp_return_disc(struct sk_buff *skb, unsigned char type,
17 unsigned short reason);
18 void dn_nsp_send_link(struct sock *sk, unsigned char lsflags, char fcval);
19 void dn_nsp_send_conninit(struct sock *sk, unsigned char flags);
20
21 void dn_nsp_output(struct sock *sk);
22 int dn_nsp_check_xmit_queue(struct sock *sk, struct sk_buff *skb,
23 struct sk_buff_head *q, unsigned short acknum);
24 void dn_nsp_queue_xmit(struct sock *sk, struct sk_buff *skb, gfp_t gfp,
25 int oob);
26 unsigned long dn_nsp_persist(struct sock *sk);
27 int dn_nsp_xmit_timeout(struct sock *sk);
28
29 int dn_nsp_rx(struct sk_buff *);
30 int dn_nsp_backlog_rcv(struct sock *sk, struct sk_buff *skb);
31
32 struct sk_buff *dn_alloc_skb(struct sock *sk, int size, gfp_t pri);
33 struct sk_buff *dn_alloc_send_skb(struct sock *sk, size_t *size, int noblock,
34 long timeo, int *err);
35
36 #define NSP_REASON_OK 0 /* No error */
37 #define NSP_REASON_NR 1 /* No resources */
38 #define NSP_REASON_UN 2 /* Unrecognised node name */
39 #define NSP_REASON_SD 3 /* Node shutting down */
40 #define NSP_REASON_ID 4 /* Invalid destination end user */
41 #define NSP_REASON_ER 5 /* End user lacks resources */
42 #define NSP_REASON_OB 6 /* Object too busy */
43 #define NSP_REASON_US 7 /* Unspecified error */
44 #define NSP_REASON_TP 8 /* Third-Party abort */
45 #define NSP_REASON_EA 9 /* End user has aborted the link */
46 #define NSP_REASON_IF 10 /* Invalid node name format */
47 #define NSP_REASON_LS 11 /* Local node shutdown */
48 #define NSP_REASON_LL 32 /* Node lacks logical-link resources */
49 #define NSP_REASON_LE 33 /* End user lacks logical-link resources */
50 #define NSP_REASON_UR 34 /* Unacceptable RQSTRID or PASSWORD field */
51 #define NSP_REASON_UA 36 /* Unacceptable ACCOUNT field */
52 #define NSP_REASON_TM 38 /* End user timed out logical link */
53 #define NSP_REASON_NU 39 /* Node unreachable */
54 #define NSP_REASON_NL 41 /* No-link message */
55 #define NSP_REASON_DC 42 /* Disconnect confirm */
56 #define NSP_REASON_IO 43 /* Image data field overflow */
57
58 #define NSP_DISCINIT 0x38
59 #define NSP_DISCCONF 0x48
60
61 /*------------------------- NSP - messages ------------------------------*/
62 /* Data Messages */
63 /*---------------*/
64
65 /* Data Messages (data segment/interrupt/link service) */
66
67 struct nsp_data_seg_msg {
68 __u8 msgflg;
69 __le16 dstaddr;
70 __le16 srcaddr;
71 } __packed;
72
73 struct nsp_data_opt_msg {
74 __le16 acknum;
75 __le16 segnum;
76 __le16 lsflgs;
77 } __packed;
78
79 struct nsp_data_opt_msg1 {
80 __le16 acknum;
81 __le16 segnum;
82 } __packed;
83
84
85 /* Acknowledgment Message (data/other data) */
86 struct nsp_data_ack_msg {
87 __u8 msgflg;
88 __le16 dstaddr;
89 __le16 srcaddr;
90 __le16 acknum;
91 } __packed;
92
93 /* Connect Acknowledgment Message */
94 struct nsp_conn_ack_msg {
95 __u8 msgflg;
96 __le16 dstaddr;
97 } __packed;
98
99
100 /* Connect Initiate/Retransmit Initiate/Connect Confirm */
101 struct nsp_conn_init_msg {
102 __u8 msgflg;
103 #define NSP_CI 0x18 /* Connect Initiate */
104 #define NSP_RCI 0x68 /* Retrans. Conn Init */
105 __le16 dstaddr;
106 __le16 srcaddr;
107 __u8 services;
108 #define NSP_FC_NONE 0x00 /* Flow Control None */
109 #define NSP_FC_SRC 0x04 /* Seg Req. Count */
110 #define NSP_FC_SCMC 0x08 /* Sess. Control Mess */
111 #define NSP_FC_MASK 0x0c /* FC type mask */
112 __u8 info;
113 __le16 segsize;
114 } __packed;
115
116 /* Disconnect Initiate/Disconnect Confirm */
117 struct nsp_disconn_init_msg {
118 __u8 msgflg;
119 __le16 dstaddr;
120 __le16 srcaddr;
121 __le16 reason;
122 } __packed;
123
124
125
126 struct srcobj_fmt {
127 __u8 format;
128 __u8 task;
129 __le16 grpcode;
130 __le16 usrcode;
131 __u8 dlen;
132 } __packed;
133
134 /*
135 * A collection of functions for manipulating the sequence
136 * numbers used in NSP. Similar in operation to the functions
137 * of the same name in TCP.
138 */
dn_before(__u16 seq1,__u16 seq2)139 static __inline__ int dn_before(__u16 seq1, __u16 seq2)
140 {
141 seq1 &= 0x0fff;
142 seq2 &= 0x0fff;
143
144 return (int)((seq1 - seq2) & 0x0fff) > 2048;
145 }
146
147
dn_after(__u16 seq1,__u16 seq2)148 static __inline__ int dn_after(__u16 seq1, __u16 seq2)
149 {
150 seq1 &= 0x0fff;
151 seq2 &= 0x0fff;
152
153 return (int)((seq2 - seq1) & 0x0fff) > 2048;
154 }
155
dn_equal(__u16 seq1,__u16 seq2)156 static __inline__ int dn_equal(__u16 seq1, __u16 seq2)
157 {
158 return ((seq1 ^ seq2) & 0x0fff) == 0;
159 }
160
dn_before_or_equal(__u16 seq1,__u16 seq2)161 static __inline__ int dn_before_or_equal(__u16 seq1, __u16 seq2)
162 {
163 return (dn_before(seq1, seq2) || dn_equal(seq1, seq2));
164 }
165
seq_add(__u16 * seq,__u16 off)166 static __inline__ void seq_add(__u16 *seq, __u16 off)
167 {
168 (*seq) += off;
169 (*seq) &= 0x0fff;
170 }
171
seq_next(__u16 seq1,__u16 seq2)172 static __inline__ int seq_next(__u16 seq1, __u16 seq2)
173 {
174 return dn_equal(seq1 + 1, seq2);
175 }
176
177 /*
178 * Can we delay the ack ?
179 */
sendack(__u16 seq)180 static __inline__ int sendack(__u16 seq)
181 {
182 return (int)((seq & 0x1000) ? 0 : 1);
183 }
184
185 /*
186 * Is socket congested ?
187 */
dn_congested(struct sock * sk)188 static __inline__ int dn_congested(struct sock *sk)
189 {
190 return atomic_read(&sk->sk_rmem_alloc) > (sk->sk_rcvbuf >> 1);
191 }
192
193 #define DN_MAX_NSP_DATA_HEADER (11)
194
195 #endif /* _NET_DN_NSP_H */
196