net/dccp/ccid.h

   1 #ifndef _CCID_H
   2 #define _CCID_H
   3 /*
   4  *  net/dccp/ccid.h
   5  *
   6  *  An implementation of the DCCP protocol
   7  *  Arnaldo Carvalho de Melo <acme@conectiva.com.br>
   8  *
   9  *  CCID infrastructure
  10  *
  11  *      This program is free software; you can redistribute it and/or modify it
  12  *      under the terms of the GNU General Public License version 2 as
  13  *      published by the Free Software Foundation.
  14  */
  15
  16 #include <net/sock.h>
  17 #include <linux/compiler.h>
  18 #include <linux/dccp.h>
  19 #include <linux/list.h>
  20 #include <linux/module.h>
  21
  22 #define CCID_MAX 255
  23
  24 struct tcp_info;
  25
  26 /**
  27  *  struct ccid_operations  -  Interface to Congestion-Control Infrastructure
  28  *
  29  *  @ccid_id: numerical CCID ID (up to %CCID_MAX, cf. table 5 in RFC 4340, 10.)
  30  *  @ccid_ccmps: the CCMPS including network/transport headers (0 when disabled)
  31  *  @ccid_name: alphabetical identifier string for @ccid_id
  32  *  @ccid_owner: module which implements/owns this CCID
  33  *  @ccid_hc_{r,t}x_slab: memory pool for the receiver/sender half-connection
  34  *  @ccid_hc_{r,t}x_obj_size: size of the receiver/sender half-connection socket
  35  *
  36  *  @ccid_hc_{r,t}x_init: CCID-specific initialisation routine (before startup)
  37  *  @ccid_hc_{r,t}x_exit: CCID-specific cleanup routine (before destruction)
  38  *  @ccid_hc_rx_packet_recv: implements the HC-receiver side
  39  *  @ccid_hc_{r,t}x_parse_options: parsing routine for CCID/HC-specific options
  40  *  @ccid_hc_{r,t}x_insert_options: insert routine for CCID/HC-specific options
  41  *  @ccid_hc_tx_packet_recv: implements feedback processing for the HC-sender
  42  *  @ccid_hc_tx_send_packet: implements the sending part of the HC-sender
  43  *  @ccid_hc_tx_packet_sent: does accounting for packets in flight by HC-sender
  44  *  @ccid_hc_{r,t}x_get_info: INET_DIAG information for HC-receiver/sender
  45  *  @ccid_hc_{r,t}x_getsockopt: socket options specific to HC-receiver/sender
  46  */
  47 struct ccid_operations {
  48         unsigned char           ccid_id;
  49         __u32                   ccid_ccmps;
  50         const char              *ccid_name;
  51         struct module           *ccid_owner;
  52         struct kmem_cache       *ccid_hc_rx_slab,
  53                                 *ccid_hc_tx_slab;
  54         __u32                   ccid_hc_rx_obj_size,
  55                                 ccid_hc_tx_obj_size;
  56         /* Interface Routines */
  57         int             (*ccid_hc_rx_init)(struct ccid *ccid, struct sock *sk);
  58         int             (*ccid_hc_tx_init)(struct ccid *ccid, struct sock *sk);
  59         void            (*ccid_hc_rx_exit)(struct sock *sk);
  60         void            (*ccid_hc_tx_exit)(struct sock *sk);
  61         void            (*ccid_hc_rx_packet_recv)(struct sock *sk,
  62                                                   struct sk_buff *skb);
  63         int             (*ccid_hc_rx_parse_options)(struct sock *sk,
  64                                                     unsigned char option,
  65                                                     unsigned char len, u16 idx,
  66                                                     unsigned char* value);
  67         int             (*ccid_hc_rx_insert_options)(struct sock *sk,
  68                                                      struct sk_buff *skb);
  69         void            (*ccid_hc_tx_packet_recv)(struct sock *sk,
  70                                                   struct sk_buff *skb);
  71         int             (*ccid_hc_tx_parse_options)(struct sock *sk,
  72                                                     unsigned char option,
  73                                                     unsigned char len, u16 idx,
  74                                                     unsigned char* value);
  75         int             (*ccid_hc_tx_send_packet)(struct sock *sk,
  76                                                   struct sk_buff *skb);
  77         void            (*ccid_hc_tx_packet_sent)(struct sock *sk,
  78                                                   int more, unsigned int len);
  79         void            (*ccid_hc_rx_get_info)(struct sock *sk,
  80                                                struct tcp_info *info);
  81         void            (*ccid_hc_tx_get_info)(struct sock *sk,
  82                                                struct tcp_info *info);
  83         int             (*ccid_hc_rx_getsockopt)(struct sock *sk,
  84                                                  const int optname, int len,
  85                                                  u32 __user *optval,
  86                                                  int __user *optlen);
  87         int             (*ccid_hc_tx_getsockopt)(struct sock *sk,
  88                                                  const int optname, int len,
  89                                                  u32 __user *optval,
  90                                                  int __user *optlen);
  91 };
  92
  93 extern int ccid_register(struct ccid_operations *ccid_ops);
  94 extern int ccid_unregister(struct ccid_operations *ccid_ops);
  95
  96 struct ccid {
  97         struct ccid_operations *ccid_ops;
  98         char                   ccid_priv[0];
  99 };
 100
 101 static inline void *ccid_priv(const struct ccid *ccid)
 102 {
 103         return (void *)ccid->ccid_priv;
 104 }
 105
 106 extern bool ccid_support_check(u8 const *ccid_array, u8 array_len);
 107 extern int  ccid_get_builtin_ccids(u8 **ccid_array, u8 *array_len);
 108 extern int  ccid_getsockopt_builtin_ccids(struct sock *sk, int len,
 109                                           char __user *, int __user *);
 110
 111 extern struct ccid *ccid_new(unsigned char id, struct sock *sk, int rx,
 112                              gfp_t gfp);
 113
 114 static inline int ccid_get_current_rx_ccid(struct dccp_sock *dp)
 115 {
 116         struct ccid *ccid = dp->dccps_hc_rx_ccid;
 117
 118         if (ccid == NULL || ccid->ccid_ops == NULL)
 119                 return -1;
 120         return ccid->ccid_ops->ccid_id;
 121 }
 122
 123 static inline int ccid_get_current_tx_ccid(struct dccp_sock *dp)
 124 {
 125         struct ccid *ccid = dp->dccps_hc_tx_ccid;
 126
 127         if (ccid == NULL || ccid->ccid_ops == NULL)
 128                 return -1;
 129         return ccid->ccid_ops->ccid_id;
 130 }
 131
 132 extern void ccid_hc_rx_delete(struct ccid *ccid, struct sock *sk);
 133 extern void ccid_hc_tx_delete(struct ccid *ccid, struct sock *sk);
 134
 135 static inline int ccid_hc_tx_send_packet(struct ccid *ccid, struct sock *sk,
 136                                          struct sk_buff *skb)
 137 {
 138         int rc = 0;
 139         if (ccid->ccid_ops->ccid_hc_tx_send_packet != NULL)
 140                 rc = ccid->ccid_ops->ccid_hc_tx_send_packet(sk, skb);
 141         return rc;
 142 }
 143
 144 static inline void ccid_hc_tx_packet_sent(struct ccid *ccid, struct sock *sk,
 145                                           int more, unsigned int len)
 146 {
 147         if (ccid->ccid_ops->ccid_hc_tx_packet_sent != NULL)
 148                 ccid->ccid_ops->ccid_hc_tx_packet_sent(sk, more, len);
 149 }
 150
 151 static inline void ccid_hc_rx_packet_recv(struct ccid *ccid, struct sock *sk,
 152                                           struct sk_buff *skb)
 153 {
 154         if (ccid->ccid_ops->ccid_hc_rx_packet_recv != NULL)
 155                 ccid->ccid_ops->ccid_hc_rx_packet_recv(sk, skb);
 156 }
 157
 158 static inline void ccid_hc_tx_packet_recv(struct ccid *ccid, struct sock *sk,
 159                                           struct sk_buff *skb)
 160 {
 161         if (ccid->ccid_ops->ccid_hc_tx_packet_recv != NULL)
 162                 ccid->ccid_ops->ccid_hc_tx_packet_recv(sk, skb);
 163 }
 164
 165 static inline int ccid_hc_tx_parse_options(struct ccid *ccid, struct sock *sk,
 166                                            unsigned char option,
 167                                            unsigned char len, u16 idx,
 168                                            unsigned char* value)
 169 {
 170         int rc = 0;
 171         if (ccid->ccid_ops->ccid_hc_tx_parse_options != NULL)
 172                 rc = ccid->ccid_ops->ccid_hc_tx_parse_options(sk, option, len, idx,
 173                                                     value);
 174         return rc;
 175 }
 176
 177 static inline int ccid_hc_rx_parse_options(struct ccid *ccid, struct sock *sk,
 178                                            unsigned char option,
 179                                            unsigned char len, u16 idx,
 180                                            unsigned char* value)
 181 {
 182         int rc = 0;
 183         if (ccid->ccid_ops->ccid_hc_rx_parse_options != NULL)
 184                 rc = ccid->ccid_ops->ccid_hc_rx_parse_options(sk, option, len, idx, value);
 185         return rc;
 186 }
 187
 188 static inline int ccid_hc_rx_insert_options(struct ccid *ccid, struct sock *sk,
 189                                             struct sk_buff *skb)
 190 {
 191         if (ccid->ccid_ops->ccid_hc_rx_insert_options != NULL)
 192                 return ccid->ccid_ops->ccid_hc_rx_insert_options(sk, skb);
 193         return 0;
 194 }
 195
 196 static inline void ccid_hc_rx_get_info(struct ccid *ccid, struct sock *sk,
 197                                        struct tcp_info *info)
 198 {
 199         if (ccid->ccid_ops->ccid_hc_rx_get_info != NULL)
 200                 ccid->ccid_ops->ccid_hc_rx_get_info(sk, info);
 201 }
 202
 203 static inline void ccid_hc_tx_get_info(struct ccid *ccid, struct sock *sk,
 204                                        struct tcp_info *info)
 205 {
 206         if (ccid->ccid_ops->ccid_hc_tx_get_info != NULL)
 207                 ccid->ccid_ops->ccid_hc_tx_get_info(sk, info);
 208 }
 209
 210 static inline int ccid_hc_rx_getsockopt(struct ccid *ccid, struct sock *sk,
 211                                         const int optname, int len,
 212                                         u32 __user *optval, int __user *optlen)
 213 {
 214         int rc = -ENOPROTOOPT;
 215         if (ccid->ccid_ops->ccid_hc_rx_getsockopt != NULL)
 216                 rc = ccid->ccid_ops->ccid_hc_rx_getsockopt(sk, optname, len,
 217                                                  optval, optlen);
 218         return rc;
 219 }
 220
 221 static inline int ccid_hc_tx_getsockopt(struct ccid *ccid, struct sock *sk,
 222                                         const int optname, int len,
 223                                         u32 __user *optval, int __user *optlen)
 224 {
 225         int rc = -ENOPROTOOPT;
 226         if (ccid->ccid_ops->ccid_hc_tx_getsockopt != NULL)
 227                 rc = ccid->ccid_ops->ccid_hc_tx_getsockopt(sk, optname, len,
 228                                                  optval, optlen);
 229         return rc;
 230 }
 231 #endif /* _CCID_H */