linux TCP/IP协议栈中protocol结构体

 

socket->sk->sk_prot是一个传输层协议绑定的操作集，比如对于IPPROTO_TCP，它就是tcp_prot，对于IPPROTO_UDP，它就是 udp_prot。而对于类型为SOCK_RAW的套接字，它没有相应的传输层协议，而是用于通配所有的网络层附属协议，所以，所有网络层附属协议共用的一个操作集raw_prot。 struct proto {     close()     connect()     disconnect()     accept()     ioctl()     init()     destroy()     shutdown()     setsockopt()     getsockopt()     compat_setsockopt()     compat_getsockopt()     sendmsg()     recvmsg()     sendpage()     bind()     backlog_rcv()     hash()     unhash()     get_port()     enter_memory_pressure()     atomic_t                 *memory_allocated     atomic_t                 *sockets_allocated     int                      *memory_pressure     int                      *sysctl_mem     int                      *sysctl_wmem     int                      *sysctl_rmem     int                      max_header     kmem_cache_t             *slab     unsigned int             obj_size     atomic_t                 *orphan_count     struct request_sock_ops -*rsk_prot     struct timewait_sock_ops *twsk_prot     struct module            *owner     char                     name[32]     struct list_head         node #ifdef SOCK_REFCNT_DEBUG     atomic_t                 socks #endif     struct {         int inuse         u8 __pad[SMP_CACHE_BYTES - sizeof(int)]     } stats[NR_CPUS] } tcp_prot <--> TCP ------------------------------------- struct proto tcp_prot = {     .name           = "TCP",     .owner          = THIS_MODULE,     .close          = tcp_close,     .connect        = tcp_v4_connect,     .disconnect     = tcp_disconnect,     .accept         = inet_csk_accept,     .ioctl          = tcp_ioctl,     .init           = tcp_v4_init_sock,     .destroy        = tcp_v4_destroy_sock,     .shutdown       = tcp_shutdown,     .setsockopt     = tcp_setsockopt,     .getsockopt     = tcp_getsockopt,     .sendmsg        = tcp_sendmsg,     .recvmsg        = tcp_recvmsg,     .backlog_rcv    = tcp_v4_do_rcv,     .hash           = tcp_v4_hash,     .unhash         = tcp_unhash,     .get_port       = tcp_v4_get_port,     .enter_memory_pressure = tcp_enter_memory_pressure,     .sockets_allocated = &tcp_sockets_allocated,     .orphan_count       = &tcp_orphan_count,     .memory_allocated   = &tcp_memory_allocated,     .memory_pressure    = &tcp_memory_pressure,     .sysctl_mem         = sysctl_tcp_mem,     .sysctl_wmem        = sysctl_tcp_wmem,     .sysctl_rmem        = sysctl_tcp_rmem,     .max_header         = MAX_TCP_HEADER,     .obj_size           = sizeof(struct tcp_sock),     .twsk_prot          = &tcp_timewait_sock_ops,     .rsk_prot           = &tcp_request_sock_ops, #ifdef CONFIG_COMPAT     .compat_setsockopt = compat_tcp_setsockopt,     .compat_getsockopt = compat_tcp_getsockopt, #endif }; udp_prot <--> UDP ------------------------------------- struct proto udp_prot = {     .name          = "UDP",     .owner         = THIS_MODULE,     .close         = udp_lib_close,     .connect       = ip4_datagram_connect,     .disconnect    = udp_disconnect,     .ioctl         = udp_ioctl,     .destroy       = udp_destroy_sock,     .setsockopt    = udp_setsockopt,     .getsockopt    = udp_getsockopt,     .sendmsg       = udp_sendmsg,     .recvmsg       = udp_recvmsg,     .sendpage      = udp_sendpage,     .backlog_rcv   = udp_queue_rcv_skb,     .hash          = udp_lib_hash,     .unhash        = udp_lib_unhash,     .get_port      = udp_v4_get_port,     .obj_size      = sizeof(struct udp_sock), #ifdef CONFIG_COMPAT     .compat_setsockopt = compat_udp_setsockopt,     .compat_getsockopt = compat_udp_getsockopt, #endif }; raw_prot <--> IP ------------------------------------- struct proto raw_prot = {     .name          = "RAW",     .owner         = THIS_MODULE,     .close         = raw_close,     .connect       = ip4_datagram_connect,     .disconnect    = udp_disconnect,     .ioctl         = raw_ioctl,     .init          = raw_init,     .setsockopt    = raw_setsockopt,     .getsockopt    = raw_getsockopt,     .sendmsg       = raw_sendmsg,     .recvmsg       = raw_recvmsg,     .bind          = raw_bind,     .backlog_rcv   = raw_rcv_skb,     .hash          = raw_v4_hash,     .unhash        = raw_v4_unhash,     .obj_size      = sizeof(struct raw_sock), #ifdef CONFIG_COMPAT     .compat_setsockopt = compat_raw_setsockopt,     .compat_getsockopt = compat_raw_getsockopt, #endif };