1 | /* SPDX-License-Identifier: GPL-2.0-only */ |
2 | #ifndef _CCID_H |
3 | #define _CCID_H |
4 | /* |
5 | * net/dccp/ccid.h |
6 | * |
7 | * An implementation of the DCCP protocol |
8 | * Arnaldo Carvalho de Melo <acme@conectiva.com.br> |
9 | * |
10 | * CCID infrastructure |
11 | */ |
12 | |
13 | #include <net/sock.h> |
14 | #include <linux/compiler.h> |
15 | #include <linux/dccp.h> |
16 | #include <linux/list.h> |
17 | #include <linux/module.h> |
18 | |
19 | /* maximum value for a CCID (RFC 4340, 19.5) */ |
20 | #define CCID_MAX 255 |
21 | #define CCID_SLAB_NAME_LENGTH 32 |
22 | |
23 | struct tcp_info; |
24 | |
25 | /** |
26 | * struct ccid_operations - Interface to Congestion-Control Infrastructure |
27 | * |
28 | * @ccid_id: numerical CCID ID (up to %CCID_MAX, cf. table 5 in RFC 4340, 10.) |
29 | * @ccid_ccmps: the CCMPS including network/transport headers (0 when disabled) |
30 | * @ccid_name: alphabetical identifier string for @ccid_id |
31 | * @ccid_hc_{r,t}x_slab: memory pool for the receiver/sender half-connection |
32 | * @ccid_hc_{r,t}x_obj_size: size of the receiver/sender half-connection socket |
33 | * |
34 | * @ccid_hc_{r,t}x_init: CCID-specific initialisation routine (before startup) |
35 | * @ccid_hc_{r,t}x_exit: CCID-specific cleanup routine (before destruction) |
36 | * @ccid_hc_rx_packet_recv: implements the HC-receiver side |
37 | * @ccid_hc_{r,t}x_parse_options: parsing routine for CCID/HC-specific options |
38 | * @ccid_hc_{r,t}x_insert_options: insert routine for CCID/HC-specific options |
39 | * @ccid_hc_tx_packet_recv: implements feedback processing for the HC-sender |
40 | * @ccid_hc_tx_send_packet: implements the sending part of the HC-sender |
41 | * @ccid_hc_tx_packet_sent: does accounting for packets in flight by HC-sender |
42 | * @ccid_hc_{r,t}x_get_info: INET_DIAG information for HC-receiver/sender |
43 | * @ccid_hc_{r,t}x_getsockopt: socket options specific to HC-receiver/sender |
44 | */ |
45 | struct ccid_operations { |
46 | unsigned char ccid_id; |
47 | __u32 ccid_ccmps; |
48 | const char *ccid_name; |
49 | struct kmem_cache *ccid_hc_rx_slab, |
50 | *ccid_hc_tx_slab; |
51 | char ccid_hc_rx_slab_name[CCID_SLAB_NAME_LENGTH]; |
52 | char ccid_hc_tx_slab_name[CCID_SLAB_NAME_LENGTH]; |
53 | __u32 ccid_hc_rx_obj_size, |
54 | ccid_hc_tx_obj_size; |
55 | /* Interface Routines */ |
56 | int (*ccid_hc_rx_init)(struct ccid *ccid, struct sock *sk); |
57 | int (*ccid_hc_tx_init)(struct ccid *ccid, struct sock *sk); |
58 | void (*ccid_hc_rx_exit)(struct sock *sk); |
59 | void (*ccid_hc_tx_exit)(struct sock *sk); |
60 | void (*ccid_hc_rx_packet_recv)(struct sock *sk, |
61 | struct sk_buff *skb); |
62 | int (*ccid_hc_rx_parse_options)(struct sock *sk, u8 pkt, |
63 | u8 opt, u8 *val, u8 len); |
64 | int (*ccid_hc_rx_insert_options)(struct sock *sk, |
65 | struct sk_buff *skb); |
66 | void (*ccid_hc_tx_packet_recv)(struct sock *sk, |
67 | struct sk_buff *skb); |
68 | int (*ccid_hc_tx_parse_options)(struct sock *sk, u8 pkt, |
69 | u8 opt, u8 *val, u8 len); |
70 | int (*ccid_hc_tx_send_packet)(struct sock *sk, |
71 | struct sk_buff *skb); |
72 | void (*ccid_hc_tx_packet_sent)(struct sock *sk, |
73 | unsigned int len); |
74 | void (*ccid_hc_rx_get_info)(struct sock *sk, |
75 | struct tcp_info *info); |
76 | void (*ccid_hc_tx_get_info)(struct sock *sk, |
77 | struct tcp_info *info); |
78 | int (*ccid_hc_rx_getsockopt)(struct sock *sk, |
79 | const int optname, int len, |
80 | u32 __user *optval, |
81 | int __user *optlen); |
82 | int (*ccid_hc_tx_getsockopt)(struct sock *sk, |
83 | const int optname, int len, |
84 | u32 __user *optval, |
85 | int __user *optlen); |
86 | }; |
87 | |
88 | extern struct ccid_operations ccid2_ops; |
89 | #ifdef CONFIG_IP_DCCP_CCID3 |
90 | extern struct ccid_operations ccid3_ops; |
91 | #endif |
92 | |
93 | int ccid_initialize_builtins(void); |
94 | void ccid_cleanup_builtins(void); |
95 | |
96 | struct ccid { |
97 | struct ccid_operations *ccid_ops; |
98 | char ccid_priv[]; |
99 | }; |
100 | |
101 | static inline void *ccid_priv(const struct ccid *ccid) |
102 | { |
103 | return (void *)ccid->ccid_priv; |
104 | } |
105 | |
106 | bool ccid_support_check(u8 const *ccid_array, u8 array_len); |
107 | int ccid_get_builtin_ccids(u8 **ccid_array, u8 *array_len); |
108 | int ccid_getsockopt_builtin_ccids(struct sock *sk, int len, |
109 | char __user *, int __user *); |
110 | |
111 | struct ccid *ccid_new(const u8 id, struct sock *sk, bool rx); |
112 | |
113 | static inline int ccid_get_current_rx_ccid(struct dccp_sock *dp) |
114 | { |
115 | struct ccid *ccid = dp->dccps_hc_rx_ccid; |
116 | |
117 | if (ccid == NULL || ccid->ccid_ops == NULL) |
118 | return -1; |
119 | return ccid->ccid_ops->ccid_id; |
120 | } |
121 | |
122 | static inline int ccid_get_current_tx_ccid(struct dccp_sock *dp) |
123 | { |
124 | struct ccid *ccid = dp->dccps_hc_tx_ccid; |
125 | |
126 | if (ccid == NULL || ccid->ccid_ops == NULL) |
127 | return -1; |
128 | return ccid->ccid_ops->ccid_id; |
129 | } |
130 | |
131 | void ccid_hc_rx_delete(struct ccid *ccid, struct sock *sk); |
132 | void ccid_hc_tx_delete(struct ccid *ccid, struct sock *sk); |
133 | |
134 | /* |
135 | * Congestion control of queued data packets via CCID decision. |
136 | * |
137 | * The TX CCID performs its congestion-control by indicating whether and when a |
138 | * queued packet may be sent, using the return code of ccid_hc_tx_send_packet(). |
139 | * The following modes are supported via the symbolic constants below: |
140 | * - timer-based pacing (CCID returns a delay value in milliseconds); |
141 | * - autonomous dequeueing (CCID internally schedules dccps_xmitlet). |
142 | */ |
143 | |
144 | enum ccid_dequeueing_decision { |
145 | CCID_PACKET_SEND_AT_ONCE = 0x00000, /* "green light": no delay */ |
146 | CCID_PACKET_DELAY_MAX = 0x0FFFF, /* maximum delay in msecs */ |
147 | CCID_PACKET_DELAY = 0x10000, /* CCID msec-delay mode */ |
148 | CCID_PACKET_WILL_DEQUEUE_LATER = 0x20000, /* CCID autonomous mode */ |
149 | CCID_PACKET_ERR = 0xF0000, /* error condition */ |
150 | }; |
151 | |
152 | static inline int ccid_packet_dequeue_eval(const int return_code) |
153 | { |
154 | if (return_code < 0) |
155 | return CCID_PACKET_ERR; |
156 | if (return_code == 0) |
157 | return CCID_PACKET_SEND_AT_ONCE; |
158 | if (return_code <= CCID_PACKET_DELAY_MAX) |
159 | return CCID_PACKET_DELAY; |
160 | return return_code; |
161 | } |
162 | |
163 | static inline int ccid_hc_tx_send_packet(struct ccid *ccid, struct sock *sk, |
164 | struct sk_buff *skb) |
165 | { |
166 | if (ccid->ccid_ops->ccid_hc_tx_send_packet != NULL) |
167 | return ccid->ccid_ops->ccid_hc_tx_send_packet(sk, skb); |
168 | return CCID_PACKET_SEND_AT_ONCE; |
169 | } |
170 | |
171 | static inline void ccid_hc_tx_packet_sent(struct ccid *ccid, struct sock *sk, |
172 | unsigned int len) |
173 | { |
174 | if (ccid->ccid_ops->ccid_hc_tx_packet_sent != NULL) |
175 | ccid->ccid_ops->ccid_hc_tx_packet_sent(sk, len); |
176 | } |
177 | |
178 | static inline void ccid_hc_rx_packet_recv(struct ccid *ccid, struct sock *sk, |
179 | struct sk_buff *skb) |
180 | { |
181 | if (ccid->ccid_ops->ccid_hc_rx_packet_recv != NULL) |
182 | ccid->ccid_ops->ccid_hc_rx_packet_recv(sk, skb); |
183 | } |
184 | |
185 | static inline void ccid_hc_tx_packet_recv(struct ccid *ccid, struct sock *sk, |
186 | struct sk_buff *skb) |
187 | { |
188 | if (ccid->ccid_ops->ccid_hc_tx_packet_recv != NULL) |
189 | ccid->ccid_ops->ccid_hc_tx_packet_recv(sk, skb); |
190 | } |
191 | |
192 | /** |
193 | * ccid_hc_tx_parse_options - Parse CCID-specific options sent by the receiver |
194 | * @pkt: type of packet that @opt appears on (RFC 4340, 5.1) |
195 | * @opt: the CCID-specific option type (RFC 4340, 5.8 and 10.3) |
196 | * @val: value of @opt |
197 | * @len: length of @val in bytes |
198 | */ |
199 | static inline int ccid_hc_tx_parse_options(struct ccid *ccid, struct sock *sk, |
200 | u8 pkt, u8 opt, u8 *val, u8 len) |
201 | { |
202 | if (!ccid || !ccid->ccid_ops->ccid_hc_tx_parse_options) |
203 | return 0; |
204 | return ccid->ccid_ops->ccid_hc_tx_parse_options(sk, pkt, opt, val, len); |
205 | } |
206 | |
207 | /** |
208 | * ccid_hc_rx_parse_options - Parse CCID-specific options sent by the sender |
209 | * Arguments are analogous to ccid_hc_tx_parse_options() |
210 | */ |
211 | static inline int ccid_hc_rx_parse_options(struct ccid *ccid, struct sock *sk, |
212 | u8 pkt, u8 opt, u8 *val, u8 len) |
213 | { |
214 | if (!ccid || !ccid->ccid_ops->ccid_hc_rx_parse_options) |
215 | return 0; |
216 | return ccid->ccid_ops->ccid_hc_rx_parse_options(sk, pkt, opt, val, len); |
217 | } |
218 | |
219 | static inline int ccid_hc_rx_insert_options(struct ccid *ccid, struct sock *sk, |
220 | struct sk_buff *skb) |
221 | { |
222 | if (ccid->ccid_ops->ccid_hc_rx_insert_options != NULL) |
223 | return ccid->ccid_ops->ccid_hc_rx_insert_options(sk, skb); |
224 | return 0; |
225 | } |
226 | |
227 | static inline void ccid_hc_rx_get_info(struct ccid *ccid, struct sock *sk, |
228 | struct tcp_info *info) |
229 | { |
230 | if (ccid->ccid_ops->ccid_hc_rx_get_info != NULL) |
231 | ccid->ccid_ops->ccid_hc_rx_get_info(sk, info); |
232 | } |
233 | |
234 | static inline void ccid_hc_tx_get_info(struct ccid *ccid, struct sock *sk, |
235 | struct tcp_info *info) |
236 | { |
237 | if (ccid->ccid_ops->ccid_hc_tx_get_info != NULL) |
238 | ccid->ccid_ops->ccid_hc_tx_get_info(sk, info); |
239 | } |
240 | |
241 | static inline int ccid_hc_rx_getsockopt(struct ccid *ccid, struct sock *sk, |
242 | const int optname, int len, |
243 | u32 __user *optval, int __user *optlen) |
244 | { |
245 | int rc = -ENOPROTOOPT; |
246 | if (ccid != NULL && ccid->ccid_ops->ccid_hc_rx_getsockopt != NULL) |
247 | rc = ccid->ccid_ops->ccid_hc_rx_getsockopt(sk, optname, len, |
248 | optval, optlen); |
249 | return rc; |
250 | } |
251 | |
252 | static inline int ccid_hc_tx_getsockopt(struct ccid *ccid, struct sock *sk, |
253 | const int optname, int len, |
254 | u32 __user *optval, int __user *optlen) |
255 | { |
256 | int rc = -ENOPROTOOPT; |
257 | if (ccid != NULL && ccid->ccid_ops->ccid_hc_tx_getsockopt != NULL) |
258 | rc = ccid->ccid_ops->ccid_hc_tx_getsockopt(sk, optname, len, |
259 | optval, optlen); |
260 | return rc; |
261 | } |
262 | #endif /* _CCID_H */ |
263 | |