diff options
Diffstat (limited to 'net/dccp/ccid.h')
| -rw-r--r-- | net/dccp/ccid.h | 262 |
1 files changed, 262 insertions, 0 deletions
diff --git a/net/dccp/ccid.h b/net/dccp/ccid.h new file mode 100644 index 000000000..105f3734d --- /dev/null +++ b/net/dccp/ccid.h @@ -0,0 +1,262 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +#ifndef _CCID_H +#define _CCID_H +/* + * net/dccp/ccid.h + * + * An implementation of the DCCP protocol + * Arnaldo Carvalho de Melo <acme@conectiva.com.br> + * + * CCID infrastructure + */ + +#include <net/sock.h> +#include <linux/compiler.h> +#include <linux/dccp.h> +#include <linux/list.h> +#include <linux/module.h> + +/* maximum value for a CCID (RFC 4340, 19.5) */ +#define CCID_MAX 255 +#define CCID_SLAB_NAME_LENGTH 32 + +struct tcp_info; + +/** + * struct ccid_operations - Interface to Congestion-Control Infrastructure + * + * @ccid_id: numerical CCID ID (up to %CCID_MAX, cf. table 5 in RFC 4340, 10.) + * @ccid_ccmps: the CCMPS including network/transport headers (0 when disabled) + * @ccid_name: alphabetical identifier string for @ccid_id + * @ccid_hc_{r,t}x_slab: memory pool for the receiver/sender half-connection + * @ccid_hc_{r,t}x_obj_size: size of the receiver/sender half-connection socket + * + * @ccid_hc_{r,t}x_init: CCID-specific initialisation routine (before startup) + * @ccid_hc_{r,t}x_exit: CCID-specific cleanup routine (before destruction) + * @ccid_hc_rx_packet_recv: implements the HC-receiver side + * @ccid_hc_{r,t}x_parse_options: parsing routine for CCID/HC-specific options + * @ccid_hc_{r,t}x_insert_options: insert routine for CCID/HC-specific options + * @ccid_hc_tx_packet_recv: implements feedback processing for the HC-sender + * @ccid_hc_tx_send_packet: implements the sending part of the HC-sender + * @ccid_hc_tx_packet_sent: does accounting for packets in flight by HC-sender + * @ccid_hc_{r,t}x_get_info: INET_DIAG information for HC-receiver/sender + * @ccid_hc_{r,t}x_getsockopt: socket options specific to HC-receiver/sender + */ +struct ccid_operations { + unsigned char ccid_id; + __u32 ccid_ccmps; + const char *ccid_name; + struct kmem_cache *ccid_hc_rx_slab, + *ccid_hc_tx_slab; + char ccid_hc_rx_slab_name[CCID_SLAB_NAME_LENGTH]; + char ccid_hc_tx_slab_name[CCID_SLAB_NAME_LENGTH]; + __u32 ccid_hc_rx_obj_size, + ccid_hc_tx_obj_size; + /* Interface Routines */ + int (*ccid_hc_rx_init)(struct ccid *ccid, struct sock *sk); + int (*ccid_hc_tx_init)(struct ccid *ccid, struct sock *sk); + void (*ccid_hc_rx_exit)(struct sock *sk); + void (*ccid_hc_tx_exit)(struct sock *sk); + void (*ccid_hc_rx_packet_recv)(struct sock *sk, + struct sk_buff *skb); + int (*ccid_hc_rx_parse_options)(struct sock *sk, u8 pkt, + u8 opt, u8 *val, u8 len); + int (*ccid_hc_rx_insert_options)(struct sock *sk, + struct sk_buff *skb); + void (*ccid_hc_tx_packet_recv)(struct sock *sk, + struct sk_buff *skb); + int (*ccid_hc_tx_parse_options)(struct sock *sk, u8 pkt, + u8 opt, u8 *val, u8 len); + int (*ccid_hc_tx_send_packet)(struct sock *sk, + struct sk_buff *skb); + void (*ccid_hc_tx_packet_sent)(struct sock *sk, + unsigned int len); + void (*ccid_hc_rx_get_info)(struct sock *sk, + struct tcp_info *info); + void (*ccid_hc_tx_get_info)(struct sock *sk, + struct tcp_info *info); + int (*ccid_hc_rx_getsockopt)(struct sock *sk, + const int optname, int len, + u32 __user *optval, + int __user *optlen); + int (*ccid_hc_tx_getsockopt)(struct sock *sk, + const int optname, int len, + u32 __user *optval, + int __user *optlen); +}; + +extern struct ccid_operations ccid2_ops; +#ifdef CONFIG_IP_DCCP_CCID3 +extern struct ccid_operations ccid3_ops; +#endif + +int ccid_initialize_builtins(void); +void ccid_cleanup_builtins(void); + +struct ccid { + struct ccid_operations *ccid_ops; + char ccid_priv[]; +}; + +static inline void *ccid_priv(const struct ccid *ccid) +{ + return (void *)ccid->ccid_priv; +} + +bool ccid_support_check(u8 const *ccid_array, u8 array_len); +int ccid_get_builtin_ccids(u8 **ccid_array, u8 *array_len); +int ccid_getsockopt_builtin_ccids(struct sock *sk, int len, + char __user *, int __user *); + +struct ccid *ccid_new(const u8 id, struct sock *sk, bool rx); + +static inline int ccid_get_current_rx_ccid(struct dccp_sock *dp) +{ + struct ccid *ccid = dp->dccps_hc_rx_ccid; + + if (ccid == NULL || ccid->ccid_ops == NULL) + return -1; + return ccid->ccid_ops->ccid_id; +} + +static inline int ccid_get_current_tx_ccid(struct dccp_sock *dp) +{ + struct ccid *ccid = dp->dccps_hc_tx_ccid; + + if (ccid == NULL || ccid->ccid_ops == NULL) + return -1; + return ccid->ccid_ops->ccid_id; +} + +void ccid_hc_rx_delete(struct ccid *ccid, struct sock *sk); +void ccid_hc_tx_delete(struct ccid *ccid, struct sock *sk); + +/* + * Congestion control of queued data packets via CCID decision. + * + * The TX CCID performs its congestion-control by indicating whether and when a + * queued packet may be sent, using the return code of ccid_hc_tx_send_packet(). + * The following modes are supported via the symbolic constants below: + * - timer-based pacing (CCID returns a delay value in milliseconds); + * - autonomous dequeueing (CCID internally schedules dccps_xmitlet). + */ + +enum ccid_dequeueing_decision { + CCID_PACKET_SEND_AT_ONCE = 0x00000, /* "green light": no delay */ + CCID_PACKET_DELAY_MAX = 0x0FFFF, /* maximum delay in msecs */ + CCID_PACKET_DELAY = 0x10000, /* CCID msec-delay mode */ + CCID_PACKET_WILL_DEQUEUE_LATER = 0x20000, /* CCID autonomous mode */ + CCID_PACKET_ERR = 0xF0000, /* error condition */ +}; + +static inline int ccid_packet_dequeue_eval(const int return_code) +{ + if (return_code < 0) + return CCID_PACKET_ERR; + if (return_code == 0) + return CCID_PACKET_SEND_AT_ONCE; + if (return_code <= CCID_PACKET_DELAY_MAX) + return CCID_PACKET_DELAY; + return return_code; +} + +static inline int ccid_hc_tx_send_packet(struct ccid *ccid, struct sock *sk, + struct sk_buff *skb) +{ + if (ccid->ccid_ops->ccid_hc_tx_send_packet != NULL) + return ccid->ccid_ops->ccid_hc_tx_send_packet(sk, skb); + return CCID_PACKET_SEND_AT_ONCE; +} + +static inline void ccid_hc_tx_packet_sent(struct ccid *ccid, struct sock *sk, + unsigned int len) +{ + if (ccid->ccid_ops->ccid_hc_tx_packet_sent != NULL) + ccid->ccid_ops->ccid_hc_tx_packet_sent(sk, len); +} + +static inline void ccid_hc_rx_packet_recv(struct ccid *ccid, struct sock *sk, + struct sk_buff *skb) +{ + if (ccid->ccid_ops->ccid_hc_rx_packet_recv != NULL) + ccid->ccid_ops->ccid_hc_rx_packet_recv(sk, skb); +} + +static inline void ccid_hc_tx_packet_recv(struct ccid *ccid, struct sock *sk, + struct sk_buff *skb) +{ + if (ccid->ccid_ops->ccid_hc_tx_packet_recv != NULL) + ccid->ccid_ops->ccid_hc_tx_packet_recv(sk, skb); +} + +/** + * ccid_hc_tx_parse_options - Parse CCID-specific options sent by the receiver + * @pkt: type of packet that @opt appears on (RFC 4340, 5.1) + * @opt: the CCID-specific option type (RFC 4340, 5.8 and 10.3) + * @val: value of @opt + * @len: length of @val in bytes + */ +static inline int ccid_hc_tx_parse_options(struct ccid *ccid, struct sock *sk, + u8 pkt, u8 opt, u8 *val, u8 len) +{ + if (!ccid || !ccid->ccid_ops->ccid_hc_tx_parse_options) + return 0; + return ccid->ccid_ops->ccid_hc_tx_parse_options(sk, pkt, opt, val, len); +} + +/** + * ccid_hc_rx_parse_options - Parse CCID-specific options sent by the sender + * Arguments are analogous to ccid_hc_tx_parse_options() + */ +static inline int ccid_hc_rx_parse_options(struct ccid *ccid, struct sock *sk, + u8 pkt, u8 opt, u8 *val, u8 len) +{ + if (!ccid || !ccid->ccid_ops->ccid_hc_rx_parse_options) + return 0; + return ccid->ccid_ops->ccid_hc_rx_parse_options(sk, pkt, opt, val, len); +} + +static inline int ccid_hc_rx_insert_options(struct ccid *ccid, struct sock *sk, + struct sk_buff *skb) +{ + if (ccid->ccid_ops->ccid_hc_rx_insert_options != NULL) + return ccid->ccid_ops->ccid_hc_rx_insert_options(sk, skb); + return 0; +} + +static inline void ccid_hc_rx_get_info(struct ccid *ccid, struct sock *sk, + struct tcp_info *info) +{ + if (ccid->ccid_ops->ccid_hc_rx_get_info != NULL) + ccid->ccid_ops->ccid_hc_rx_get_info(sk, info); +} + +static inline void ccid_hc_tx_get_info(struct ccid *ccid, struct sock *sk, + struct tcp_info *info) +{ + if (ccid->ccid_ops->ccid_hc_tx_get_info != NULL) + ccid->ccid_ops->ccid_hc_tx_get_info(sk, info); +} + +static inline int ccid_hc_rx_getsockopt(struct ccid *ccid, struct sock *sk, + const int optname, int len, + u32 __user *optval, int __user *optlen) +{ + int rc = -ENOPROTOOPT; + if (ccid != NULL && ccid->ccid_ops->ccid_hc_rx_getsockopt != NULL) + rc = ccid->ccid_ops->ccid_hc_rx_getsockopt(sk, optname, len, + optval, optlen); + return rc; +} + +static inline int ccid_hc_tx_getsockopt(struct ccid *ccid, struct sock *sk, + const int optname, int len, + u32 __user *optval, int __user *optlen) +{ + int rc = -ENOPROTOOPT; + if (ccid != NULL && ccid->ccid_ops->ccid_hc_tx_getsockopt != NULL) + rc = ccid->ccid_ops->ccid_hc_tx_getsockopt(sk, optname, len, + optval, optlen); + return rc; +} +#endif /* _CCID_H */ |