1 /* SPDX-License-Identifier: GPL-2.0-or-later */
4 /******************************************************************************
5 (c) 1995-1998 E.M. Serrat emserrat@geocities.com
7 *******************************************************************************/
8 /* dn_nsp.c functions prototyping */
9 #include <linux/atomic.h>
10 #include <linux/types.h>
16 void dn_nsp_send_data_ack(struct sock *sk);
17 void dn_nsp_send_oth_ack(struct sock *sk);
18 void dn_send_conn_ack(struct sock *sk);
19 void dn_send_conn_conf(struct sock *sk, gfp_t gfp);
20 void dn_nsp_send_disc(struct sock *sk, unsigned char type,
21 unsigned short reason, gfp_t gfp);
22 void dn_nsp_return_disc(struct sk_buff *skb, unsigned char type,
23 unsigned short reason);
24 void dn_nsp_send_link(struct sock *sk, unsigned char lsflags, char fcval);
25 void dn_nsp_send_conninit(struct sock *sk, unsigned char flags);
27 void dn_nsp_output(struct sock *sk);
28 int dn_nsp_check_xmit_queue(struct sock *sk, struct sk_buff *skb,
29 struct sk_buff_head *q, unsigned short acknum);
30 void dn_nsp_queue_xmit(struct sock *sk, struct sk_buff *skb, gfp_t gfp,
32 unsigned long dn_nsp_persist(struct sock *sk);
33 int dn_nsp_xmit_timeout(struct sock *sk);
35 int dn_nsp_rx(struct sk_buff *);
36 int dn_nsp_backlog_rcv(struct sock *sk, struct sk_buff *skb);
38 struct sk_buff *dn_alloc_skb(struct sock *sk, int size, gfp_t pri);
39 struct sk_buff *dn_alloc_send_skb(struct sock *sk, size_t *size, int noblock,
40 long timeo, int *err);
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 */
64 #define NSP_DISCINIT 0x38
65 #define NSP_DISCCONF 0x48
67 /*------------------------- NSP - messages ------------------------------*/
71 /* Data Messages (data segment/interrupt/link service) */
73 struct nsp_data_seg_msg {
79 struct nsp_data_opt_msg {
85 struct nsp_data_opt_msg1 {
91 /* Acknowledgment Message (data/other data) */
92 struct nsp_data_ack_msg {
99 /* Connect Acknowledgment Message */
100 struct nsp_conn_ack_msg {
106 /* Connect Initiate/Retransmit Initiate/Connect Confirm */
107 struct nsp_conn_init_msg {
109 #define NSP_CI 0x18 /* Connect Initiate */
110 #define NSP_RCI 0x68 /* Retrans. Conn Init */
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 */
122 /* Disconnect Initiate/Disconnect Confirm */
123 struct nsp_disconn_init_msg {
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.
145 static __inline__ int dn_before(__u16 seq1, __u16 seq2)
150 return (int)((seq1 - seq2) & 0x0fff) > 2048;
154 static __inline__ int dn_after(__u16 seq1, __u16 seq2)
159 return (int)((seq2 - seq1) & 0x0fff) > 2048;
162 static __inline__ int dn_equal(__u16 seq1, __u16 seq2)
164 return ((seq1 ^ seq2) & 0x0fff) == 0;
167 static __inline__ int dn_before_or_equal(__u16 seq1, __u16 seq2)
169 return (dn_before(seq1, seq2) || dn_equal(seq1, seq2));
172 static __inline__ void seq_add(__u16 *seq, __u16 off)
178 static __inline__ int seq_next(__u16 seq1, __u16 seq2)
180 return dn_equal(seq1 + 1, seq2);
184 * Can we delay the ack ?
186 static __inline__ int sendack(__u16 seq)
188 return (int)((seq & 0x1000) ? 0 : 1);
192 * Is socket congested ?
194 static __inline__ int dn_congested(struct sock *sk)
196 return atomic_read(&sk->sk_rmem_alloc) > (sk->sk_rcvbuf >> 1);
199 #define DN_MAX_NSP_DATA_HEADER (11)
201 #endif /* _NET_DN_NSP_H */