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 /* maximum value for a CCID (RFC 4340, 19.5) */
  23 #define CCID_MAX                255
  24 #define CCID_SLAB_NAME_LENGTH   32
  25
  26 struct tcp_info;
  27
  28 /**
  29  *  struct ccid_operations  -  Interface to Congestion-Control Infrastructure
  30  *
  31  *  @ccid_id: numerical CCID ID (up to %CCID_MAX, cf. table 5 in RFC 4340, 10.)
  32  *  @ccid_ccmps: the CCMPS including network/transport headers (0 when disabled)
  33  *  @ccid_name: alphabetical identifier string for @ccid_id
  34  *  @ccid_hc_{r,t}x_slab: memory pool for the receiver/sender half-connection
  35  *  @ccid_hc_{r,t}x_obj_size: size of the receiver/sender half-connection socket
  36  *
  37  *  @ccid_hc_{r,t}x_init: CCID-specific initialisation routine (before startup)
  38  *  @ccid_hc_{r,t}x_exit: CCID-specific cleanup routine (before destruction)
  39  *  @ccid_hc_rx_packet_recv: implements the HC-receiver side
  40  *  @ccid_hc_{r,t}x_parse_options: parsing routine for CCID/HC-specific options
  41  *  @ccid_hc_{r,t}x_insert_options: insert routine for CCID/HC-specific options
  42  *  @ccid_hc_tx_packet_recv: implements feedback processing for the HC-sender
  43  *  @ccid_hc_tx_send_packet: implements the sending part of the HC-sender
  44  *  @ccid_hc_tx_packet_sent: does accounting for packets in flight by HC-sender
  45  *  @ccid_hc_{r,t}x_get_info: INET_DIAG information for HC-receiver/sender
  46  *  @ccid_hc_{r,t}x_getsockopt: socket options specific to HC-receiver/sender
  47  */
  48 struct ccid_operations {
  49         unsigned char           ccid_id;
  50         __u32                   ccid_ccmps;
  51         const char              *ccid_name;
  52         struct kmem_cache       *ccid_hc_rx_slab,
  53                                 *ccid_hc_tx_slab;
  54         char                    ccid_hc_rx_slab_name[CCID_SLAB_NAME_LENGTH];
  55         char                    ccid_hc_tx_slab_name[CCID_SLAB_NAME_LENGTH];
  56         __u32                   ccid_hc_rx_obj_size,
  57                                 ccid_hc_tx_obj_size;
  58         /* Interface Routines */
  59         int             (*ccid_hc_rx_init)(struct ccid *ccid, struct sock *sk);
  60         int             (*ccid_hc_tx_init)(struct ccid *ccid, struct sock *sk);
  61         void            (*ccid_hc_rx_exit)(struct sock *sk);
  62         void            (*ccid_hc_tx_exit)(struct sock *sk);
  63         void            (*ccid_hc_rx_packet_recv)(struct sock *sk,
  64                                                   struct sk_buff *skb);
  65         int             (*ccid_hc_rx_parse_options)(struct sock *sk,
  66                                                     unsigned char option,
  67                                                     unsigned char len, u16 idx,
  68                                                     unsigned char* value);
  69         int             (*ccid_hc_rx_insert_options)(struct sock *sk,
  70                                                      struct sk_buff *skb);
  71         void            (*ccid_hc_tx_packet_recv)(struct sock *sk,
  72                                                   struct sk_buff *skb);
  73         int             (*ccid_hc_tx_parse_options)(struct sock *sk,
  74                                                     unsigned char option,
  75                                                     unsigned char len, u16 idx,
  76                                                     unsigned char* value);
  77         int             (*ccid_hc_tx_send_packet)(struct sock *sk,
  78                                                   struct sk_buff *skb);
  79         void            (*ccid_hc_tx_packet_sent)(struct sock *sk,
  80                                                   int more, unsigned int len);
  81         void            (*ccid_hc_rx_get_info)(struct sock *sk,
  82                                                struct tcp_info *info);
  83         void            (*ccid_hc_tx_get_info)(struct sock *sk,
  84                                                struct tcp_info *info);
  85         int             (*ccid_hc_rx_getsockopt)(struct sock *sk,
  86                                                  const int optname, int len,
  87                                                  u32 __user *optval,
  88                                                  int __user *optlen);
  89         int             (*ccid_hc_tx_getsockopt)(struct sock *sk,
  90                                                  const int optname, int len,
  91                                                  u32 __user *optval,
  92                                                  int __user *optlen);
  93 };
  94
  95 extern struct ccid_operations ccid2_ops;
  96 #ifdef CONFIG_IP_DCCP_CCID3
  97 extern struct ccid_operations ccid3_ops;
  98 #endif
  99
 100 extern int  ccid_initialize_builtins(void);
 101 extern void ccid_cleanup_builtins(void);
 102
 103 struct ccid {
 104         struct ccid_operations *ccid_ops;
 105         char                   ccid_priv[0];
 106 };
 107
 108 static inline void *ccid_priv(const struct ccid *ccid)
 109 {
 110         return (void *)ccid->ccid_priv;
 111 }
 112
 113 extern bool ccid_support_check(u8 const *ccid_array, u8 array_len);
 114 extern int  ccid_get_builtin_ccids(u8 **ccid_array, u8 *array_len);
 115 extern int  ccid_getsockopt_builtin_ccids(struct sock *sk, int len,
 116                                           char __user *, int __user *);
 117
 118 extern struct ccid *ccid_new(const u8 id, struct sock *sk, bool rx);
 119
 120 static inline int ccid_get_current_rx_ccid(struct dccp_sock *dp)
 121 {
 122         struct ccid *ccid = dp->dccps_hc_rx_ccid;
 123
 124         if (ccid == NULL || ccid->ccid_ops == NULL)
 125                 return -1;
 126         return ccid->ccid_ops->ccid_id;
 127 }
 128
 129 static inline int ccid_get_current_tx_ccid(struct dccp_sock *dp)
 130 {
 131         struct ccid *ccid = dp->dccps_hc_tx_ccid;
 132
 133         if (ccid == NULL || ccid->ccid_ops == NULL)
 134                 return -1;
 135         return ccid->ccid_ops->ccid_id;
 136 }
 137
 138 extern void ccid_hc_rx_delete(struct ccid *ccid, struct sock *sk);
 139 extern void ccid_hc_tx_delete(struct ccid *ccid, struct sock *sk);
 140
 141 static inline int ccid_hc_tx_send_packet(struct ccid *ccid, struct sock *sk,
 142                                          struct sk_buff *skb)
 143 {
 144         int rc = 0;
 145         if (ccid->ccid_ops->ccid_hc_tx_send_packet != NULL)
 146                 rc = ccid->ccid_ops->ccid_hc_tx_send_packet(sk, skb);
 147         return rc;
 148 }
 149
 150 static inline void ccid_hc_tx_packet_sent(struct ccid *ccid, struct sock *sk,
 151                                           int more, unsigned int len)
 152 {
 153         if (ccid->ccid_ops->ccid_hc_tx_packet_sent != NULL)
 154                 ccid->ccid_ops->ccid_hc_tx_packet_sent(sk, more, len);
 155 }
 156
 157 static inline void ccid_hc_rx_packet_recv(struct ccid *ccid, struct sock *sk,
 158                                           struct sk_buff *skb)
 159 {
 160         if (ccid->ccid_ops->ccid_hc_rx_packet_recv != NULL)
 161                 ccid->ccid_ops->ccid_hc_rx_packet_recv(sk, skb);
 162 }
 163
 164 static inline void ccid_hc_tx_packet_recv(struct ccid *ccid, struct sock *sk,
 165                                           struct sk_buff *skb)
 166 {
 167         if (ccid->ccid_ops->ccid_hc_tx_packet_recv != NULL)
 168                 ccid->ccid_ops->ccid_hc_tx_packet_recv(sk, skb);
 169 }
 170
 171 static inline int ccid_hc_tx_parse_options(struct ccid *ccid, struct sock *sk,
 172                                            unsigned char option,
 173                                            unsigned char len, u16 idx,
 174                                            unsigned char* value)
 175 {
 176         int rc = 0;
 177         if (ccid->ccid_ops->ccid_hc_tx_parse_options != NULL)
 178                 rc = ccid->ccid_ops->ccid_hc_tx_parse_options(sk, option, len, idx,
 179                                                     value);
 180         return rc;
 181 }
 182
 183 static inline int ccid_hc_rx_parse_options(struct ccid *ccid, struct sock *sk,
 184                                            unsigned char option,
 185                                            unsigned char len, u16 idx,
 186                                            unsigned char* value)
 187 {
 188         int rc = 0;
 189         if (ccid->ccid_ops->ccid_hc_rx_parse_options != NULL)
 190                 rc = ccid->ccid_ops->ccid_hc_rx_parse_options(sk, option, len, idx, value);
 191         return rc;
 192 }
 193
 194 static inline int ccid_hc_rx_insert_options(struct ccid *ccid, struct sock *sk,
 195                                             struct sk_buff *skb)
 196 {
 197         if (ccid->ccid_ops->ccid_hc_rx_insert_options != NULL)
 198                 return ccid->ccid_ops->ccid_hc_rx_insert_options(sk, skb);
 199         return 0;
 200 }
 201
 202 static inline void ccid_hc_rx_get_info(struct ccid *ccid, struct sock *sk,
 203                                        struct tcp_info *info)
 204 {
 205         if (ccid->ccid_ops->ccid_hc_rx_get_info != NULL)
 206                 ccid->ccid_ops->ccid_hc_rx_get_info(sk, info);
 207 }
 208
 209 static inline void ccid_hc_tx_get_info(struct ccid *ccid, struct sock *sk,
 210                                        struct tcp_info *info)
 211 {
 212         if (ccid->ccid_ops->ccid_hc_tx_get_info != NULL)
 213                 ccid->ccid_ops->ccid_hc_tx_get_info(sk, info);
 214 }
 215
 216 static inline int ccid_hc_rx_getsockopt(struct ccid *ccid, struct sock *sk,
 217                                         const int optname, int len,
 218                                         u32 __user *optval, int __user *optlen)
 219 {
 220         int rc = -ENOPROTOOPT;
 221         if (ccid->ccid_ops->ccid_hc_rx_getsockopt != NULL)
 222                 rc = ccid->ccid_ops->ccid_hc_rx_getsockopt(sk, optname, len,
 223                                                  optval, optlen);
 224         return rc;
 225 }
 226
 227 static inline int ccid_hc_tx_getsockopt(struct ccid *ccid, struct sock *sk,
 228                                         const int optname, int len,
 229                                         u32 __user *optval, int __user *optlen)
 230 {
 231         int rc = -ENOPROTOOPT;
 232         if (ccid->ccid_ops->ccid_hc_tx_getsockopt != NULL)
 233                 rc = ccid->ccid_ops->ccid_hc_tx_getsockopt(sk, optname, len,
 234                                                  optval, optlen);
 235         return rc;
 236 }
 237 #endif /* _CCID_H */