net/ipv4/af_inet.c

File Facts

System

Linux kernel

Corpus path

net/ipv4/af_inet.c

Extension

.c

Size

51082 bytes

Lines

2057

Domain

Networking Core

Bucket

Sockets, Protocols, Packet Path, And Network Policy

Inferred role

Networking Core: operation-table or driver-model contract

Status

pattern implementation candidate

Why This File Exists

Networking stack implementation surface: socket APIs, protocol dispatch, packet flow, routing, filtering, and network namespaces.

• Networking stack implementation surface: socket APIs, protocol dispatch, packet flow, routing, filtering, and network namespaces.
• Defines an operation table; this is where Linux turns generic core objects into subsystem-specific behavior.
• Touches user memory; correctness depends on fault-safe copying and privilege boundary handling.
• Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
• Allocates kernel memory; connect allocation flags and lifetime to context constraints.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• linux/err.h
• linux/errno.h
• linux/types.h
• linux/socket.h
• linux/in.h
• linux/kernel.h
• linux/kmod.h
• linux/sched.h
• linux/timer.h
• linux/string.h
• linux/sockios.h
• linux/net.h
• linux/capability.h
• linux/fcntl.h
• linux/mm.h
• linux/interrupt.h
• linux/stat.h
• linux/init.h
• linux/poll.h
• linux/netfilter_ipv4.h
• linux/random.h
• linux/slab.h
• linux/uaccess.h
• linux/inet.h
• linux/igmp.h
• linux/inetdevice.h
• linux/netdevice.h
• net/checksum.h
• net/ip.h
• net/protocol.h
• net/arp.h
• net/route.h

Detected Declarations

• function inet_sock_destruct
• function inet_autobind
• function __inet_listen_sk
• function inet_listen
• function inet_create
• function NULL
• function inet_bind_sk
• function inet_bind
• function __inet_bind
• function inet_dgram_connect
• function inet_wait_for_connect
• function Connect
• function __inet_stream_connect
• function write
• function inet_stream_connect
• function __inet_accept
• function inet_accept
• function inet_getname
• function inet_send_prepare
• function inet_sendmsg
• function inet_splice_eof
• function inet_recvmsg
• function inet_shutdown
• function ioctl
• function inet_compat_routing_ioctl
• function inet_compat_ioctl
• function inet_register_protosw
• function inet_unregister_protosw
• function inet_sk_reselect_saddr
• function inet_sk_rebuild_header
• function inet_sk_set_state
• function inet_sk_state_store
• function list_for_each_entry
• function inet_current_timestamp
• function inet_recv_error
• function inet_gro_complete
• function ipip_gro_complete
• function inet_ctl_sock_create
• function snmp_fold_field
• function snmp_get_cpu_field64
• function snmp_fold_field64
• function for_each_possible_cpu
• function ipv4_mib_init_net
• function for_each_possible_cpu
• function ipv4_mib_exit_net
• function init_ipv4_mibs
• function inet_init_net
• function init_inet_pernet_ops

Annotated Snippet

const struct proto_ops inet_stream_ops = {
	.family		   = PF_INET,
	.owner		   = THIS_MODULE,
	.release	   = inet_release,
	.bind		   = inet_bind,
	.connect	   = inet_stream_connect,
	.socketpair	   = sock_no_socketpair,
	.accept		   = inet_accept,
	.getname	   = inet_getname,
	.poll		   = tcp_poll,
	.ioctl		   = inet_ioctl,
	.gettstamp	   = sock_gettstamp,
	.listen		   = inet_listen,
	.shutdown	   = inet_shutdown,
	.setsockopt	   = sock_common_setsockopt,
	.getsockopt	   = sock_common_getsockopt,
	.sendmsg	   = inet_sendmsg,
	.recvmsg	   = inet_recvmsg,
#ifdef CONFIG_MMU
	.mmap		   = tcp_mmap,
#endif
	.splice_eof	   = inet_splice_eof,
	.splice_read	   = tcp_splice_read,
	.set_peek_off      = sk_set_peek_off,
	.read_sock	   = tcp_read_sock,
	.read_skb	   = tcp_read_skb,
	.sendmsg_locked    = tcp_sendmsg_locked,
	.peek_len	   = tcp_peek_len,
#ifdef CONFIG_COMPAT
	.compat_ioctl	   = inet_compat_ioctl,
#endif
	.set_rcvlowat	   = tcp_set_rcvlowat,
	.set_rcvbuf	   = tcp_set_rcvbuf,
};
EXPORT_SYMBOL(inet_stream_ops);

const struct proto_ops inet_dgram_ops = {
	.family		   = PF_INET,
	.owner		   = THIS_MODULE,
	.release	   = inet_release,
	.bind		   = inet_bind,
	.connect	   = inet_dgram_connect,
	.socketpair	   = sock_no_socketpair,
	.accept		   = sock_no_accept,
	.getname	   = inet_getname,
	.poll		   = udp_poll,
	.ioctl		   = inet_ioctl,
	.gettstamp	   = sock_gettstamp,
	.listen		   = sock_no_listen,
	.shutdown	   = inet_shutdown,
	.setsockopt	   = sock_common_setsockopt,
	.getsockopt	   = sock_common_getsockopt,
	.sendmsg	   = inet_sendmsg,
	.read_skb	   = udp_read_skb,
	.recvmsg	   = inet_recvmsg,
	.mmap		   = sock_no_mmap,
	.splice_eof	   = inet_splice_eof,
	.set_peek_off	   = udp_set_peek_off,
#ifdef CONFIG_COMPAT
	.compat_ioctl	   = inet_compat_ioctl,
#endif
};
EXPORT_SYMBOL(inet_dgram_ops);

/*
 * For SOCK_RAW sockets; should be the same as inet_dgram_ops but without
 * udp_poll
 */
static const struct proto_ops inet_sockraw_ops = {
	.family		   = PF_INET,
	.owner		   = THIS_MODULE,
	.release	   = inet_release,
	.bind		   = inet_bind,
	.connect	   = inet_dgram_connect,
	.socketpair	   = sock_no_socketpair,
	.accept		   = sock_no_accept,
	.getname	   = inet_getname,
	.poll		   = datagram_poll,
	.ioctl		   = inet_ioctl,
	.gettstamp	   = sock_gettstamp,
	.listen		   = sock_no_listen,
	.shutdown	   = inet_shutdown,
	.setsockopt	   = sock_common_setsockopt,
	.getsockopt	   = sock_common_getsockopt,
	.sendmsg	   = inet_sendmsg,
	.recvmsg	   = inet_recvmsg,
	.mmap		   = sock_no_mmap,
	.splice_eof	   = inet_splice_eof,
#ifdef CONFIG_COMPAT
	.compat_ioctl	   = inet_compat_ioctl,

Annotation

• Immediate include surface: `linux/err.h`, `linux/errno.h`, `linux/types.h`, `linux/socket.h`, `linux/in.h`, `linux/kernel.h`, `linux/kmod.h`, `linux/sched.h`.
• Detected declarations: `function inet_sock_destruct`, `function inet_autobind`, `function __inet_listen_sk`, `function inet_listen`, `function inet_create`, `function NULL`, `function inet_bind_sk`, `function inet_bind`, `function __inet_bind`, `function inet_dgram_connect`.
• Atlas domain: Networking Core / Sockets, Protocols, Packet Path, And Network Policy.
• Implementation status: pattern implementation candidate.
• This snippet crosses the user/kernel memory boundary; validate fault handling and access checks before translating the pattern.
• Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.

Implementation Notes

• This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
• Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
• Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.