diff options
Diffstat (limited to '')
| -rw-r--r-- | net/ipv4/af_inet.c | 2125 |
1 files changed, 2125 insertions, 0 deletions
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c new file mode 100644 index 000000000..2f646335d --- /dev/null +++ b/net/ipv4/af_inet.c @@ -0,0 +1,2125 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * INET An implementation of the TCP/IP protocol suite for the LINUX + * operating system. INET is implemented using the BSD Socket + * interface as the means of communication with the user level. + * + * PF_INET protocol family socket handler. + * + * Authors: Ross Biro + * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> + * Florian La Roche, <flla@stud.uni-sb.de> + * Alan Cox, <A.Cox@swansea.ac.uk> + * + * Changes (see also sock.c) + * + * piggy, + * Karl Knutson : Socket protocol table + * A.N.Kuznetsov : Socket death error in accept(). + * John Richardson : Fix non blocking error in connect() + * so sockets that fail to connect + * don't return -EINPROGRESS. + * Alan Cox : Asynchronous I/O support + * Alan Cox : Keep correct socket pointer on sock + * structures + * when accept() ed + * Alan Cox : Semantics of SO_LINGER aren't state + * moved to close when you look carefully. + * With this fixed and the accept bug fixed + * some RPC stuff seems happier. + * Niibe Yutaka : 4.4BSD style write async I/O + * Alan Cox, + * Tony Gale : Fixed reuse semantics. + * Alan Cox : bind() shouldn't abort existing but dead + * sockets. Stops FTP netin:.. I hope. + * Alan Cox : bind() works correctly for RAW sockets. + * Note that FreeBSD at least was broken + * in this respect so be careful with + * compatibility tests... + * Alan Cox : routing cache support + * Alan Cox : memzero the socket structure for + * compactness. + * Matt Day : nonblock connect error handler + * Alan Cox : Allow large numbers of pending sockets + * (eg for big web sites), but only if + * specifically application requested. + * Alan Cox : New buffering throughout IP. Used + * dumbly. + * Alan Cox : New buffering now used smartly. + * Alan Cox : BSD rather than common sense + * interpretation of listen. + * Germano Caronni : Assorted small races. + * Alan Cox : sendmsg/recvmsg basic support. + * Alan Cox : Only sendmsg/recvmsg now supported. + * Alan Cox : Locked down bind (see security list). + * Alan Cox : Loosened bind a little. + * Mike McLagan : ADD/DEL DLCI Ioctls + * Willy Konynenberg : Transparent proxying support. + * David S. Miller : New socket lookup architecture. + * Some other random speedups. + * Cyrus Durgin : Cleaned up file for kmod hacks. + * Andi Kleen : Fix inet_stream_connect TCP race. + */ + +#define pr_fmt(fmt) "IPv4: " fmt + +#include <linux/err.h> +#include <linux/errno.h> +#include <linux/types.h> +#include <linux/socket.h> +#include <linux/in.h> +#include <linux/kernel.h> +#include <linux/kmod.h> +#include <linux/sched.h> +#include <linux/timer.h> +#include <linux/string.h> +#include <linux/sockios.h> +#include <linux/net.h> +#include <linux/capability.h> +#include <linux/fcntl.h> +#include <linux/mm.h> +#include <linux/interrupt.h> +#include <linux/stat.h> +#include <linux/init.h> +#include <linux/poll.h> +#include <linux/netfilter_ipv4.h> +#include <linux/random.h> +#include <linux/slab.h> + +#include <linux/uaccess.h> + +#include <linux/inet.h> +#include <linux/igmp.h> +#include <linux/inetdevice.h> +#include <linux/netdevice.h> +#include <net/checksum.h> +#include <net/ip.h> +#include <net/protocol.h> +#include <net/arp.h> +#include <net/route.h> +#include <net/ip_fib.h> +#include <net/inet_connection_sock.h> +#include <net/gro.h> +#include <net/tcp.h> +#include <net/udp.h> +#include <net/udplite.h> +#include <net/ping.h> +#include <linux/skbuff.h> +#include <net/sock.h> +#include <net/raw.h> +#include <net/icmp.h> +#include <net/inet_common.h> +#include <net/ip_tunnels.h> +#include <net/xfrm.h> +#include <net/net_namespace.h> +#include <net/secure_seq.h> +#ifdef CONFIG_IP_MROUTE +#include <linux/mroute.h> +#endif +#include <net/l3mdev.h> +#include <net/compat.h> + +#include <trace/events/sock.h> + +/* The inetsw table contains everything that inet_create needs to + * build a new socket. + */ +static struct list_head inetsw[SOCK_MAX]; +static DEFINE_SPINLOCK(inetsw_lock); + +/* New destruction routine */ + +void inet_sock_destruct(struct sock *sk) +{ + struct inet_sock *inet = inet_sk(sk); + + __skb_queue_purge(&sk->sk_receive_queue); + __skb_queue_purge(&sk->sk_error_queue); + + sk_mem_reclaim_final(sk); + + if (sk->sk_type == SOCK_STREAM && sk->sk_state != TCP_CLOSE) { + pr_err("Attempt to release TCP socket in state %d %p\n", + sk->sk_state, sk); + return; + } + if (!sock_flag(sk, SOCK_DEAD)) { + pr_err("Attempt to release alive inet socket %p\n", sk); + return; + } + + WARN_ON_ONCE(atomic_read(&sk->sk_rmem_alloc)); + WARN_ON_ONCE(refcount_read(&sk->sk_wmem_alloc)); + WARN_ON_ONCE(sk->sk_wmem_queued); + WARN_ON_ONCE(sk_forward_alloc_get(sk)); + + kfree(rcu_dereference_protected(inet->inet_opt, 1)); + dst_release(rcu_dereference_protected(sk->sk_dst_cache, 1)); + dst_release(rcu_dereference_protected(sk->sk_rx_dst, 1)); + sk_refcnt_debug_dec(sk); +} +EXPORT_SYMBOL(inet_sock_destruct); + +/* + * The routines beyond this point handle the behaviour of an AF_INET + * socket object. Mostly it punts to the subprotocols of IP to do + * the work. + */ + +/* + * Automatically bind an unbound socket. + */ + +static int inet_autobind(struct sock *sk) +{ + struct inet_sock *inet; + /* We may need to bind the socket. */ + lock_sock(sk); + inet = inet_sk(sk); + if (!inet->inet_num) { + if (sk->sk_prot->get_port(sk, 0)) { + release_sock(sk); + return -EAGAIN; + } + inet->inet_sport = htons(inet->inet_num); + } + release_sock(sk); + return 0; +} + +/* + * Move a socket into listening state. + */ +int inet_listen(struct socket *sock, int backlog) +{ + struct sock *sk = sock->sk; + unsigned char old_state; + int err, tcp_fastopen; + + lock_sock(sk); + + err = -EINVAL; + if (sock->state != SS_UNCONNECTED || sock->type != SOCK_STREAM) + goto out; + + old_state = sk->sk_state; + if (!((1 << old_state) & (TCPF_CLOSE | TCPF_LISTEN))) + goto out; + + WRITE_ONCE(sk->sk_max_ack_backlog, backlog); + /* Really, if the socket is already in listen state + * we can only allow the backlog to be adjusted. + */ + if (old_state != TCP_LISTEN) { + /* Enable TFO w/o requiring TCP_FASTOPEN socket option. + * Note that only TCP sockets (SOCK_STREAM) will reach here. + * Also fastopen backlog may already been set via the option + * because the socket was in TCP_LISTEN state previously but + * was shutdown() rather than close(). + */ + tcp_fastopen = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_fastopen); + if ((tcp_fastopen & TFO_SERVER_WO_SOCKOPT1) && + (tcp_fastopen & TFO_SERVER_ENABLE) && + !inet_csk(sk)->icsk_accept_queue.fastopenq.max_qlen) { + fastopen_queue_tune(sk, backlog); + tcp_fastopen_init_key_once(sock_net(sk)); + } + + err = inet_csk_listen_start(sk); + if (err) + goto out; + tcp_call_bpf(sk, BPF_SOCK_OPS_TCP_LISTEN_CB, 0, NULL); + } + err = 0; + +out: + release_sock(sk); + return err; +} +EXPORT_SYMBOL(inet_listen); + +/* + * Create an inet socket. + */ + +static int inet_create(struct net *net, struct socket *sock, int protocol, + int kern) +{ + struct sock *sk; + struct inet_protosw *answer; + struct inet_sock *inet; + struct proto *answer_prot; + unsigned char answer_flags; + int try_loading_module = 0; + int err; + + if (protocol < 0 || protocol >= IPPROTO_MAX) + return -EINVAL; + + sock->state = SS_UNCONNECTED; + + /* Look for the requested type/protocol pair. */ +lookup_protocol: + err = -ESOCKTNOSUPPORT; + rcu_read_lock(); + list_for_each_entry_rcu(answer, &inetsw[sock->type], list) { + + err = 0; + /* Check the non-wild match. */ + if (protocol == answer->protocol) { + if (protocol != IPPROTO_IP) + break; + } else { + /* Check for the two wild cases. */ + if (IPPROTO_IP == protocol) { + protocol = answer->protocol; + break; + } + if (IPPROTO_IP == answer->protocol) + break; + } + err = -EPROTONOSUPPORT; + } + + if (unlikely(err)) { + if (try_loading_module < 2) { + rcu_read_unlock(); + /* + * Be more specific, e.g. net-pf-2-proto-132-type-1 + * (net-pf-PF_INET-proto-IPPROTO_SCTP-type-SOCK_STREAM) + */ + if (++try_loading_module == 1) + request_module("net-pf-%d-proto-%d-type-%d", + PF_INET, protocol, sock->type); + /* + * Fall back to generic, e.g. net-pf-2-proto-132 + * (net-pf-PF_INET-proto-IPPROTO_SCTP) + */ + else + request_module("net-pf-%d-proto-%d", + PF_INET, protocol); + goto lookup_protocol; + } else + goto out_rcu_unlock; + } + + err = -EPERM; + if (sock->type == SOCK_RAW && !kern && + !ns_capable(net->user_ns, CAP_NET_RAW)) + goto out_rcu_unlock; + + sock->ops = answer->ops; + answer_prot = answer->prot; + answer_flags = answer->flags; + rcu_read_unlock(); + + WARN_ON(!answer_prot->slab); + + err = -ENOMEM; + sk = sk_alloc(net, PF_INET, GFP_KERNEL, answer_prot, kern); + if (!sk) + goto out; + + err = 0; + if (INET_PROTOSW_REUSE & answer_flags) + sk->sk_reuse = SK_CAN_REUSE; + + if (INET_PROTOSW_ICSK & answer_flags) + inet_init_csk_locks(sk); + + inet = inet_sk(sk); + inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0; + + inet->nodefrag = 0; + + if (SOCK_RAW == sock->type) { + inet->inet_num = protocol; + if (IPPROTO_RAW == protocol) + inet->hdrincl = 1; + } + + if (READ_ONCE(net->ipv4.sysctl_ip_no_pmtu_disc)) + inet->pmtudisc = IP_PMTUDISC_DONT; + else + inet->pmtudisc = IP_PMTUDISC_WANT; + + atomic_set(&inet->inet_id, 0); + + sock_init_data(sock, sk); + + sk->sk_destruct = inet_sock_destruct; + sk->sk_protocol = protocol; + sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv; + sk->sk_txrehash = READ_ONCE(net->core.sysctl_txrehash); + + inet->uc_ttl = -1; + inet->mc_loop = 1; + inet->mc_ttl = 1; + inet->mc_all = 1; + inet->mc_index = 0; + inet->mc_list = NULL; + inet->rcv_tos = 0; + + sk_refcnt_debug_inc(sk); + + if (inet->inet_num) { + /* It assumes that any protocol which allows + * the user to assign a number at socket + * creation time automatically + * shares. + */ + inet->inet_sport = htons(inet->inet_num); + /* Add to protocol hash chains. */ + err = sk->sk_prot->hash(sk); + if (err) { + sk_common_release(sk); + goto out; + } + } + + if (sk->sk_prot->init) { + err = sk->sk_prot->init(sk); + if (err) { + sk_common_release(sk); + goto out; + } + } + + if (!kern) { + err = BPF_CGROUP_RUN_PROG_INET_SOCK(sk); + if (err) { + sk_common_release(sk); + goto out; + } + } +out: + return err; +out_rcu_unlock: + rcu_read_unlock(); + goto out; +} + + +/* + * The peer socket should always be NULL (or else). When we call this + * function we are destroying the object and from then on nobody + * should refer to it. + */ +int inet_release(struct socket *sock) +{ + struct sock *sk = sock->sk; + + if (sk) { + long timeout; + + if (!sk->sk_kern_sock) + BPF_CGROUP_RUN_PROG_INET_SOCK_RELEASE(sk); + + /* Applications forget to leave groups before exiting */ + ip_mc_drop_socket(sk); + + /* If linger is set, we don't return until the close + * is complete. Otherwise we return immediately. The + * actually closing is done the same either way. + * + * If the close is due to the process exiting, we never + * linger.. + */ + timeout = 0; + if (sock_flag(sk, SOCK_LINGER) && + !(current->flags & PF_EXITING)) + timeout = sk->sk_lingertime; + sk->sk_prot->close(sk, timeout); + sock->sk = NULL; + } + return 0; +} +EXPORT_SYMBOL(inet_release); + +int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) +{ + struct sock *sk = sock->sk; + u32 flags = BIND_WITH_LOCK; + int err; + + /* If the socket has its own bind function then use it. (RAW) */ + if (sk->sk_prot->bind) { + return sk->sk_prot->bind(sk, uaddr, addr_len); + } + if (addr_len < sizeof(struct sockaddr_in)) + return -EINVAL; + + /* BPF prog is run before any checks are done so that if the prog + * changes context in a wrong way it will be caught. + */ + err = BPF_CGROUP_RUN_PROG_INET_BIND_LOCK(sk, uaddr, + CGROUP_INET4_BIND, &flags); + if (err) + return err; + + return __inet_bind(sk, uaddr, addr_len, flags); +} +EXPORT_SYMBOL(inet_bind); + +int __inet_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len, + u32 flags) +{ + struct sockaddr_in *addr = (struct sockaddr_in *)uaddr; + struct inet_sock *inet = inet_sk(sk); + struct net *net = sock_net(sk); + unsigned short snum; + int chk_addr_ret; + u32 tb_id = RT_TABLE_LOCAL; + int err; + + if (addr->sin_family != AF_INET) { + /* Compatibility games : accept AF_UNSPEC (mapped to AF_INET) + * only if s_addr is INADDR_ANY. + */ + err = -EAFNOSUPPORT; + if (addr->sin_family != AF_UNSPEC || + addr->sin_addr.s_addr != htonl(INADDR_ANY)) + goto out; + } + + tb_id = l3mdev_fib_table_by_index(net, sk->sk_bound_dev_if) ? : tb_id; + chk_addr_ret = inet_addr_type_table(net, addr->sin_addr.s_addr, tb_id); + + /* Not specified by any standard per-se, however it breaks too + * many applications when removed. It is unfortunate since + * allowing applications to make a non-local bind solves + * several problems with systems using dynamic addressing. + * (ie. your servers still start up even if your ISDN link + * is temporarily down) + */ + err = -EADDRNOTAVAIL; + if (!inet_addr_valid_or_nonlocal(net, inet, addr->sin_addr.s_addr, + chk_addr_ret)) + goto out; + + snum = ntohs(addr->sin_port); + err = -EACCES; + if (!(flags & BIND_NO_CAP_NET_BIND_SERVICE) && + snum && inet_port_requires_bind_service(net, snum) && + !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE)) + goto out; + + /* We keep a pair of addresses. rcv_saddr is the one + * used by hash lookups, and saddr is used for transmit. + * + * In the BSD API these are the same except where it + * would be illegal to use them (multicast/broadcast) in + * which case the sending device address is used. + */ + if (flags & BIND_WITH_LOCK) + lock_sock(sk); + + /* Check these errors (active socket, double bind). */ + err = -EINVAL; + if (sk->sk_state != TCP_CLOSE || inet->inet_num) + goto out_release_sock; + + inet->inet_rcv_saddr = inet->inet_saddr = addr->sin_addr.s_addr; + if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST) + inet->inet_saddr = 0; /* Use device */ + + /* Make sure we are allowed to bind here. */ + if (snum || !(inet->bind_address_no_port || + (flags & BIND_FORCE_ADDRESS_NO_PORT))) { + err = sk->sk_prot->get_port(sk, snum); + if (err) { + inet->inet_saddr = inet->inet_rcv_saddr = 0; + goto out_release_sock; + } + if (!(flags & BIND_FROM_BPF)) { + err = BPF_CGROUP_RUN_PROG_INET4_POST_BIND(sk); + if (err) { + inet->inet_saddr = inet->inet_rcv_saddr = 0; + if (sk->sk_prot->put_port) + sk->sk_prot->put_port(sk); + goto out_release_sock; + } + } + } + + if (inet->inet_rcv_saddr) + sk->sk_userlocks |= SOCK_BINDADDR_LOCK; + if (snum) + sk->sk_userlocks |= SOCK_BINDPORT_LOCK; + inet->inet_sport = htons(inet->inet_num); + inet->inet_daddr = 0; + inet->inet_dport = 0; + sk_dst_reset(sk); + err = 0; +out_release_sock: + if (flags & BIND_WITH_LOCK) + release_sock(sk); +out: + return err; +} + +int inet_dgram_connect(struct socket *sock, struct sockaddr *uaddr, + int addr_len, int flags) +{ + struct sock *sk = sock->sk; + const struct proto *prot; + int err; + + if (addr_len < sizeof(uaddr->sa_family)) + return -EINVAL; + + /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + prot = READ_ONCE(sk->sk_prot); + + if (uaddr->sa_family == AF_UNSPEC) + return prot->disconnect(sk, flags); + + if (BPF_CGROUP_PRE_CONNECT_ENABLED(sk)) { + err = prot->pre_connect(sk, uaddr, addr_len); + if (err) + return err; + } + + if (data_race(!inet_sk(sk)->inet_num) && inet_autobind(sk)) + return -EAGAIN; + return prot->connect(sk, uaddr, addr_len); +} +EXPORT_SYMBOL(inet_dgram_connect); + +static long inet_wait_for_connect(struct sock *sk, long timeo, int writebias) +{ + DEFINE_WAIT_FUNC(wait, woken_wake_function); + + add_wait_queue(sk_sleep(sk), &wait); + sk->sk_write_pending += writebias; + + /* Basic assumption: if someone sets sk->sk_err, he _must_ + * change state of the socket from TCP_SYN_*. + * Connect() does not allow to get error notifications + * without closing the socket. + */ + while ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) { + release_sock(sk); + timeo = wait_woken(&wait, TASK_INTERRUPTIBLE, timeo); + lock_sock(sk); + if (signal_pending(current) || !timeo) + break; + } + remove_wait_queue(sk_sleep(sk), &wait); + sk->sk_write_pending -= writebias; + return timeo; +} + +/* + * Connect to a remote host. There is regrettably still a little + * TCP 'magic' in here. + */ +int __inet_stream_connect(struct socket *sock, struct sockaddr *uaddr, + int addr_len, int flags, int is_sendmsg) +{ + struct sock *sk = sock->sk; + int err; + long timeo; + + /* + * uaddr can be NULL and addr_len can be 0 if: + * sk is a TCP fastopen active socket and + * TCP_FASTOPEN_CONNECT sockopt is set and + * we already have a valid cookie for this socket. + * In this case, user can call write() after connect(). + * write() will invoke tcp_sendmsg_fastopen() which calls + * __inet_stream_connect(). + */ + if (uaddr) { + if (addr_len < sizeof(uaddr->sa_family)) + return -EINVAL; + + if (uaddr->sa_family == AF_UNSPEC) { + sk->sk_disconnects++; + err = sk->sk_prot->disconnect(sk, flags); + sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED; + goto out; + } + } + + switch (sock->state) { + default: + err = -EINVAL; + goto out; + case SS_CONNECTED: + err = -EISCONN; + goto out; + case SS_CONNECTING: + if (inet_sk(sk)->defer_connect) + err = is_sendmsg ? -EINPROGRESS : -EISCONN; + else + err = -EALREADY; + /* Fall out of switch with err, set for this state */ + break; + case SS_UNCONNECTED: + err = -EISCONN; + if (sk->sk_state != TCP_CLOSE) + goto out; + + if (BPF_CGROUP_PRE_CONNECT_ENABLED(sk)) { + err = sk->sk_prot->pre_connect(sk, uaddr, addr_len); + if (err) + goto out; + } + + err = sk->sk_prot->connect(sk, uaddr, addr_len); + if (err < 0) + goto out; + + sock->state = SS_CONNECTING; + + if (!err && inet_sk(sk)->defer_connect) + goto out; + + /* Just entered SS_CONNECTING state; the only + * difference is that return value in non-blocking + * case is EINPROGRESS, rather than EALREADY. + */ + err = -EINPROGRESS; + break; + } + + timeo = sock_sndtimeo(sk, flags & O_NONBLOCK); + + if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) { + int writebias = (sk->sk_protocol == IPPROTO_TCP) && + tcp_sk(sk)->fastopen_req && + tcp_sk(sk)->fastopen_req->data ? 1 : 0; + int dis = sk->sk_disconnects; + + /* Error code is set above */ + if (!timeo || !inet_wait_for_connect(sk, timeo, writebias)) + goto out; + + err = sock_intr_errno(timeo); + if (signal_pending(current)) + goto out; + + if (dis != sk->sk_disconnects) { + err = -EPIPE; + goto out; + } + } + + /* Connection was closed by RST, timeout, ICMP error + * or another process disconnected us. + */ + if (sk->sk_state == TCP_CLOSE) + goto sock_error; + + /* sk->sk_err may be not zero now, if RECVERR was ordered by user + * and error was received after socket entered established state. + * Hence, it is handled normally after connect() return successfully. + */ + + sock->state = SS_CONNECTED; + err = 0; +out: + return err; + +sock_error: + err = sock_error(sk) ? : -ECONNABORTED; + sock->state = SS_UNCONNECTED; + sk->sk_disconnects++; + if (sk->sk_prot->disconnect(sk, flags)) + sock->state = SS_DISCONNECTING; + goto out; +} +EXPORT_SYMBOL(__inet_stream_connect); + +int inet_stream_connect(struct socket *sock, struct sockaddr *uaddr, + int addr_len, int flags) +{ + int err; + + lock_sock(sock->sk); + err = __inet_stream_connect(sock, uaddr, addr_len, flags, 0); + release_sock(sock->sk); + return err; +} +EXPORT_SYMBOL(inet_stream_connect); + +/* + * Accept a pending connection. The TCP layer now gives BSD semantics. + */ + +int inet_accept(struct socket *sock, struct socket *newsock, int flags, + bool kern) +{ + struct sock *sk1 = sock->sk, *sk2; + int err = -EINVAL; + + /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + sk2 = READ_ONCE(sk1->sk_prot)->accept(sk1, flags, &err, kern); + if (!sk2) + goto do_err; + + lock_sock(sk2); + + sock_rps_record_flow(sk2); + WARN_ON(!((1 << sk2->sk_state) & + (TCPF_ESTABLISHED | TCPF_SYN_RECV | + TCPF_CLOSE_WAIT | TCPF_CLOSE))); + + if (test_bit(SOCK_SUPPORT_ZC, &sock->flags)) + set_bit(SOCK_SUPPORT_ZC, &newsock->flags); + sock_graft(sk2, newsock); + + newsock->state = SS_CONNECTED; + err = 0; + release_sock(sk2); +do_err: + return err; +} +EXPORT_SYMBOL(inet_accept); + +/* + * This does both peername and sockname. + */ +int inet_getname(struct socket *sock, struct sockaddr *uaddr, + int peer) +{ + struct sock *sk = sock->sk; + struct inet_sock *inet = inet_sk(sk); + DECLARE_SOCKADDR(struct sockaddr_in *, sin, uaddr); + + sin->sin_family = AF_INET; + lock_sock(sk); + if (peer) { + if (!inet->inet_dport || + (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) && + peer == 1)) { + release_sock(sk); + return -ENOTCONN; + } + sin->sin_port = inet->inet_dport; + sin->sin_addr.s_addr = inet->inet_daddr; + BPF_CGROUP_RUN_SA_PROG(sk, (struct sockaddr *)sin, + CGROUP_INET4_GETPEERNAME); + } else { + __be32 addr = inet->inet_rcv_saddr; + if (!addr) + addr = inet->inet_saddr; + sin->sin_port = inet->inet_sport; + sin->sin_addr.s_addr = addr; + BPF_CGROUP_RUN_SA_PROG(sk, (struct sockaddr *)sin, + CGROUP_INET4_GETSOCKNAME); + } + release_sock(sk); + memset(sin->sin_zero, 0, sizeof(sin->sin_zero)); + return sizeof(*sin); +} +EXPORT_SYMBOL(inet_getname); + +int inet_send_prepare(struct sock *sk) +{ + sock_rps_record_flow(sk); + + /* We may need to bind the socket. */ + if (data_race(!inet_sk(sk)->inet_num) && !sk->sk_prot->no_autobind && + inet_autobind(sk)) + return -EAGAIN; + + return 0; +} +EXPORT_SYMBOL_GPL(inet_send_prepare); + +int inet_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) +{ + struct sock *sk = sock->sk; + + if (unlikely(inet_send_prepare(sk))) + return -EAGAIN; + + return INDIRECT_CALL_2(sk->sk_prot->sendmsg, tcp_sendmsg, udp_sendmsg, + sk, msg, size); +} +EXPORT_SYMBOL(inet_sendmsg); + +void inet_splice_eof(struct socket *sock) +{ + const struct proto *prot; + struct sock *sk = sock->sk; + + if (unlikely(inet_send_prepare(sk))) + return; + + /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + prot = READ_ONCE(sk->sk_prot); + if (prot->splice_eof) + prot->splice_eof(sock); +} +EXPORT_SYMBOL_GPL(inet_splice_eof); + +ssize_t inet_sendpage(struct socket *sock, struct page *page, int offset, + size_t size, int flags) +{ + struct sock *sk = sock->sk; + const struct proto *prot; + + if (unlikely(inet_send_prepare(sk))) + return -EAGAIN; + + /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + prot = READ_ONCE(sk->sk_prot); + if (prot->sendpage) + return prot->sendpage(sk, page, offset, size, flags); + return sock_no_sendpage(sock, page, offset, size, flags); +} +EXPORT_SYMBOL(inet_sendpage); + +INDIRECT_CALLABLE_DECLARE(int udp_recvmsg(struct sock *, struct msghdr *, + size_t, int, int *)); +int inet_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, + int flags) +{ + struct sock *sk = sock->sk; + int addr_len = 0; + int err; + + if (likely(!(flags & MSG_ERRQUEUE))) + sock_rps_record_flow(sk); + + err = INDIRECT_CALL_2(sk->sk_prot->recvmsg, tcp_recvmsg, udp_recvmsg, + sk, msg, size, flags, &addr_len); + if (err >= 0) + msg->msg_namelen = addr_len; + return err; +} +EXPORT_SYMBOL(inet_recvmsg); + +int inet_shutdown(struct socket *sock, int how) +{ + struct sock *sk = sock->sk; + int err = 0; + + /* This should really check to make sure + * the socket is a TCP socket. (WHY AC...) + */ + how++; /* maps 0->1 has the advantage of making bit 1 rcvs and + 1->2 bit 2 snds. + 2->3 */ + if ((how & ~SHUTDOWN_MASK) || !how) /* MAXINT->0 */ + return -EINVAL; + + lock_sock(sk); + if (sock->state == SS_CONNECTING) { + if ((1 << sk->sk_state) & + (TCPF_SYN_SENT | TCPF_SYN_RECV | TCPF_CLOSE)) + sock->state = SS_DISCONNECTING; + else + sock->state = SS_CONNECTED; + } + + switch (sk->sk_state) { + case TCP_CLOSE: + err = -ENOTCONN; + /* Hack to wake up other listeners, who can poll for + EPOLLHUP, even on eg. unconnected UDP sockets -- RR */ + fallthrough; + default: + WRITE_ONCE(sk->sk_shutdown, sk->sk_shutdown | how); + if (sk->sk_prot->shutdown) + sk->sk_prot->shutdown(sk, how); + break; + + /* Remaining two branches are temporary solution for missing + * close() in multithreaded environment. It is _not_ a good idea, + * but we have no choice until close() is repaired at VFS level. + */ + case TCP_LISTEN: + if (!(how & RCV_SHUTDOWN)) + break; + fallthrough; + case TCP_SYN_SENT: + err = sk->sk_prot->disconnect(sk, O_NONBLOCK); + sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED; + break; + } + + /* Wake up anyone sleeping in poll. */ + sk->sk_state_change(sk); + release_sock(sk); + return err; +} +EXPORT_SYMBOL(inet_shutdown); + +/* + * ioctl() calls you can issue on an INET socket. Most of these are + * device configuration and stuff and very rarely used. Some ioctls + * pass on to the socket itself. + * + * NOTE: I like the idea of a module for the config stuff. ie ifconfig + * loads the devconfigure module does its configuring and unloads it. + * There's a good 20K of config code hanging around the kernel. + */ + +int inet_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) +{ + struct sock *sk = sock->sk; + int err = 0; + struct net *net = sock_net(sk); + void __user *p = (void __user *)arg; + struct ifreq ifr; + struct rtentry rt; + + switch (cmd) { + case SIOCADDRT: + case SIOCDELRT: + if (copy_from_user(&rt, p, sizeof(struct rtentry))) + return -EFAULT; + err = ip_rt_ioctl(net, cmd, &rt); + break; + case SIOCRTMSG: + err = -EINVAL; + break; + case SIOCDARP: + case SIOCGARP: + case SIOCSARP: + err = arp_ioctl(net, cmd, (void __user *)arg); + break; + case SIOCGIFADDR: + case SIOCGIFBRDADDR: + case SIOCGIFNETMASK: + case SIOCGIFDSTADDR: + case SIOCGIFPFLAGS: + if (get_user_ifreq(&ifr, NULL, p)) + return -EFAULT; + err = devinet_ioctl(net, cmd, &ifr); + if (!err && put_user_ifreq(&ifr, p)) + err = -EFAULT; + break; + + case SIOCSIFADDR: + case SIOCSIFBRDADDR: + case SIOCSIFNETMASK: + case SIOCSIFDSTADDR: + case SIOCSIFPFLAGS: + case SIOCSIFFLAGS: + if (get_user_ifreq(&ifr, NULL, p)) + return -EFAULT; + err = devinet_ioctl(net, cmd, &ifr); + break; + default: + if (sk->sk_prot->ioctl) + err = sk->sk_prot->ioctl(sk, cmd, arg); + else + err = -ENOIOCTLCMD; + break; + } + return err; +} +EXPORT_SYMBOL(inet_ioctl); + +#ifdef CONFIG_COMPAT +static int inet_compat_routing_ioctl(struct sock *sk, unsigned int cmd, + struct compat_rtentry __user *ur) +{ + compat_uptr_t rtdev; + struct rtentry rt; + + if (copy_from_user(&rt.rt_dst, &ur->rt_dst, + 3 * sizeof(struct sockaddr)) || + get_user(rt.rt_flags, &ur->rt_flags) || + get_user(rt.rt_metric, &ur->rt_metric) || + get_user(rt.rt_mtu, &ur->rt_mtu) || + get_user(rt.rt_window, &ur->rt_window) || + get_user(rt.rt_irtt, &ur->rt_irtt) || + get_user(rtdev, &ur->rt_dev)) + return -EFAULT; + + rt.rt_dev = compat_ptr(rtdev); + return ip_rt_ioctl(sock_net(sk), cmd, &rt); +} + +static int inet_compat_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) +{ + void __user *argp = compat_ptr(arg); + struct sock *sk = sock->sk; + + switch (cmd) { + case SIOCADDRT: + case SIOCDELRT: + return inet_compat_routing_ioctl(sk, cmd, argp); + default: + if (!sk->sk_prot->compat_ioctl) + return -ENOIOCTLCMD; + return sk->sk_prot->compat_ioctl(sk, cmd, arg); + } +} +#endif /* CONFIG_COMPAT */ + +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, + .sendpage = inet_sendpage, + .splice_read = tcp_splice_read, + .read_sock = tcp_read_sock, + .read_skb = tcp_read_skb, + .sendmsg_locked = tcp_sendmsg_locked, + .sendpage_locked = tcp_sendpage_locked, + .peek_len = tcp_peek_len, +#ifdef CONFIG_COMPAT + .compat_ioctl = inet_compat_ioctl, +#endif + .set_rcvlowat = tcp_set_rcvlowat, +}; +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, + .sendpage = inet_sendpage, + .set_peek_off = sk_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, + .sendpage = inet_sendpage, +#ifdef CONFIG_COMPAT + .compat_ioctl = inet_compat_ioctl, +#endif +}; + +static const struct net_proto_family inet_family_ops = { + .family = PF_INET, + .create = inet_create, + .owner = THIS_MODULE, +}; + +/* Upon startup we insert all the elements in inetsw_array[] into + * the linked list inetsw. + */ +static struct inet_protosw inetsw_array[] = +{ + { + .type = SOCK_STREAM, + .protocol = IPPROTO_TCP, + .prot = &tcp_prot, + .ops = &inet_stream_ops, + .flags = INET_PROTOSW_PERMANENT | + INET_PROTOSW_ICSK, + }, + + { + .type = SOCK_DGRAM, + .protocol = IPPROTO_UDP, + .prot = &udp_prot, + .ops = &inet_dgram_ops, + .flags = INET_PROTOSW_PERMANENT, + }, + + { + .type = SOCK_DGRAM, + .protocol = IPPROTO_ICMP, + .prot = &ping_prot, + .ops = &inet_sockraw_ops, + .flags = INET_PROTOSW_REUSE, + }, + + { + .type = SOCK_RAW, + .protocol = IPPROTO_IP, /* wild card */ + .prot = &raw_prot, + .ops = &inet_sockraw_ops, + .flags = INET_PROTOSW_REUSE, + } +}; + +#define INETSW_ARRAY_LEN ARRAY_SIZE(inetsw_array) + +void inet_register_protosw(struct inet_protosw *p) +{ + struct list_head *lh; + struct inet_protosw *answer; + int protocol = p->protocol; + struct list_head *last_perm; + + spin_lock_bh(&inetsw_lock); + + if (p->type >= SOCK_MAX) + goto out_illegal; + + /* If we are trying to override a permanent protocol, bail. */ + last_perm = &inetsw[p->type]; + list_for_each(lh, &inetsw[p->type]) { + answer = list_entry(lh, struct inet_protosw, list); + /* Check only the non-wild match. */ + if ((INET_PROTOSW_PERMANENT & answer->flags) == 0) + break; + if (protocol == answer->protocol) + goto out_permanent; + last_perm = lh; + } + + /* Add the new entry after the last permanent entry if any, so that + * the new entry does not override a permanent entry when matched with + * a wild-card protocol. But it is allowed to override any existing + * non-permanent entry. This means that when we remove this entry, the + * system automatically returns to the old behavior. + */ + list_add_rcu(&p->list, last_perm); +out: + spin_unlock_bh(&inetsw_lock); + + return; + +out_permanent: + pr_err("Attempt to override permanent protocol %d\n", protocol); + goto out; + +out_illegal: + pr_err("Ignoring attempt to register invalid socket type %d\n", + p->type); + goto out; +} +EXPORT_SYMBOL(inet_register_protosw); + +void inet_unregister_protosw(struct inet_protosw *p) +{ + if (INET_PROTOSW_PERMANENT & p->flags) { + pr_err("Attempt to unregister permanent protocol %d\n", + p->protocol); + } else { + spin_lock_bh(&inetsw_lock); + list_del_rcu(&p->list); + spin_unlock_bh(&inetsw_lock); + + synchronize_net(); + } +} +EXPORT_SYMBOL(inet_unregister_protosw); + +static int inet_sk_reselect_saddr(struct sock *sk) +{ + struct inet_sock *inet = inet_sk(sk); + __be32 old_saddr = inet->inet_saddr; + __be32 daddr = inet->inet_daddr; + struct flowi4 *fl4; + struct rtable *rt; + __be32 new_saddr; + struct ip_options_rcu *inet_opt; + int err; + + inet_opt = rcu_dereference_protected(inet->inet_opt, + lockdep_sock_is_held(sk)); + if (inet_opt && inet_opt->opt.srr) + daddr = inet_opt->opt.faddr; + + /* Query new route. */ + fl4 = &inet->cork.fl.u.ip4; + rt = ip_route_connect(fl4, daddr, 0, sk->sk_bound_dev_if, + sk->sk_protocol, inet->inet_sport, + inet->inet_dport, sk); + if (IS_ERR(rt)) + return PTR_ERR(rt); + + new_saddr = fl4->saddr; + + if (new_saddr == old_saddr) { + sk_setup_caps(sk, &rt->dst); + return 0; + } + + err = inet_bhash2_update_saddr(sk, &new_saddr, AF_INET); + if (err) { + ip_rt_put(rt); + return err; + } + + sk_setup_caps(sk, &rt->dst); + + if (READ_ONCE(sock_net(sk)->ipv4.sysctl_ip_dynaddr) > 1) { + pr_info("%s(): shifting inet->saddr from %pI4 to %pI4\n", + __func__, &old_saddr, &new_saddr); + } + + /* + * XXX The only one ugly spot where we need to + * XXX really change the sockets identity after + * XXX it has entered the hashes. -DaveM + * + * Besides that, it does not check for connection + * uniqueness. Wait for troubles. + */ + return __sk_prot_rehash(sk); +} + +int inet_sk_rebuild_header(struct sock *sk) +{ + struct inet_sock *inet = inet_sk(sk); + struct rtable *rt = (struct rtable *)__sk_dst_check(sk, 0); + __be32 daddr; + struct ip_options_rcu *inet_opt; + struct flowi4 *fl4; + int err; + + /* Route is OK, nothing to do. */ + if (rt) + return 0; + + /* Reroute. */ + rcu_read_lock(); + inet_opt = rcu_dereference(inet->inet_opt); + daddr = inet->inet_daddr; + if (inet_opt && inet_opt->opt.srr) + daddr = inet_opt->opt.faddr; + rcu_read_unlock(); + fl4 = &inet->cork.fl.u.ip4; + rt = ip_route_output_ports(sock_net(sk), fl4, sk, daddr, inet->inet_saddr, + inet->inet_dport, inet->inet_sport, + sk->sk_protocol, RT_CONN_FLAGS(sk), + sk->sk_bound_dev_if); + if (!IS_ERR(rt)) { + err = 0; + sk_setup_caps(sk, &rt->dst); + } else { + err = PTR_ERR(rt); + + /* Routing failed... */ + sk->sk_route_caps = 0; + /* + * Other protocols have to map its equivalent state to TCP_SYN_SENT. + * DCCP maps its DCCP_REQUESTING state to TCP_SYN_SENT. -acme + */ + if (!READ_ONCE(sock_net(sk)->ipv4.sysctl_ip_dynaddr) || + sk->sk_state != TCP_SYN_SENT || + (sk->sk_userlocks & SOCK_BINDADDR_LOCK) || + (err = inet_sk_reselect_saddr(sk)) != 0) + sk->sk_err_soft = -err; + } + + return err; +} +EXPORT_SYMBOL(inet_sk_rebuild_header); + +void inet_sk_set_state(struct sock *sk, int state) +{ + trace_inet_sock_set_state(sk, sk->sk_state, state); + sk->sk_state = state; +} +EXPORT_SYMBOL(inet_sk_set_state); + +void inet_sk_state_store(struct sock *sk, int newstate) +{ + trace_inet_sock_set_state(sk, sk->sk_state, newstate); + smp_store_release(&sk->sk_state, newstate); +} + +struct sk_buff *inet_gso_segment(struct sk_buff *skb, + netdev_features_t features) +{ + bool udpfrag = false, fixedid = false, gso_partial, encap; + struct sk_buff *segs = ERR_PTR(-EINVAL); + const struct net_offload *ops; + unsigned int offset = 0; + struct iphdr *iph; + int proto, tot_len; + int nhoff; + int ihl; + int id; + + skb_reset_network_header(skb); + nhoff = skb_network_header(skb) - skb_mac_header(skb); + if (unlikely(!pskb_may_pull(skb, sizeof(*iph)))) + goto out; + + iph = ip_hdr(skb); + ihl = iph->ihl * 4; + if (ihl < sizeof(*iph)) + goto out; + + id = ntohs(iph->id); + proto = iph->protocol; + + /* Warning: after this point, iph might be no longer valid */ + if (unlikely(!pskb_may_pull(skb, ihl))) + goto out; + __skb_pull(skb, ihl); + + encap = SKB_GSO_CB(skb)->encap_level > 0; + if (encap) + features &= skb->dev->hw_enc_features; + SKB_GSO_CB(skb)->encap_level += ihl; + + skb_reset_transport_header(skb); + + segs = ERR_PTR(-EPROTONOSUPPORT); + + if (!skb->encapsulation || encap) { + udpfrag = !!(skb_shinfo(skb)->gso_type & SKB_GSO_UDP); + fixedid = !!(skb_shinfo(skb)->gso_type & SKB_GSO_TCP_FIXEDID); + + /* fixed ID is invalid if DF bit is not set */ + if (fixedid && !(ip_hdr(skb)->frag_off & htons(IP_DF))) + goto out; + } + + ops = rcu_dereference(inet_offloads[proto]); + if (likely(ops && ops->callbacks.gso_segment)) { + segs = ops->callbacks.gso_segment(skb, features); + if (!segs) + skb->network_header = skb_mac_header(skb) + nhoff - skb->head; + } + + if (IS_ERR_OR_NULL(segs)) + goto out; + + gso_partial = !!(skb_shinfo(segs)->gso_type & SKB_GSO_PARTIAL); + + skb = segs; + do { + iph = (struct iphdr *)(skb_mac_header(skb) + nhoff); + if (udpfrag) { + iph->frag_off = htons(offset >> 3); + if (skb->next) + iph->frag_off |= htons(IP_MF); + offset += skb->len - nhoff - ihl; + tot_len = skb->len - nhoff; + } else if (skb_is_gso(skb)) { + if (!fixedid) { + iph->id = htons(id); + id += skb_shinfo(skb)->gso_segs; + } + + if (gso_partial) + tot_len = skb_shinfo(skb)->gso_size + + SKB_GSO_CB(skb)->data_offset + + skb->head - (unsigned char *)iph; + else + tot_len = skb->len - nhoff; + } else { + if (!fixedid) + iph->id = htons(id++); + tot_len = skb->len - nhoff; + } + iph->tot_len = htons(tot_len); + ip_send_check(iph); + if (encap) + skb_reset_inner_headers(skb); + skb->network_header = (u8 *)iph - skb->head; + skb_reset_mac_len(skb); + } while ((skb = skb->next)); + +out: + return segs; +} + +static struct sk_buff *ipip_gso_segment(struct sk_buff *skb, + netdev_features_t features) +{ + if (!(skb_shinfo(skb)->gso_type & SKB_GSO_IPXIP4)) + return ERR_PTR(-EINVAL); + + return inet_gso_segment(skb, features); +} + +struct sk_buff *inet_gro_receive(struct list_head *head, struct sk_buff *skb) +{ + const struct net_offload *ops; + struct sk_buff *pp = NULL; + const struct iphdr *iph; + struct sk_buff *p; + unsigned int hlen; + unsigned int off; + unsigned int id; + int flush = 1; + int proto; + + off = skb_gro_offset(skb); + hlen = off + sizeof(*iph); + iph = skb_gro_header(skb, hlen, off); + if (unlikely(!iph)) + goto out; + + proto = iph->protocol; + + ops = rcu_dereference(inet_offloads[proto]); + if (!ops || !ops->callbacks.gro_receive) + goto out; + + if (*(u8 *)iph != 0x45) + goto out; + + if (ip_is_fragment(iph)) + goto out; + + if (unlikely(ip_fast_csum((u8 *)iph, 5))) + goto out; + + id = ntohl(*(__be32 *)&iph->id); + flush = (u16)((ntohl(*(__be32 *)iph) ^ skb_gro_len(skb)) | (id & ~IP_DF)); + id >>= 16; + + list_for_each_entry(p, head, list) { + struct iphdr *iph2; + u16 flush_id; + + if (!NAPI_GRO_CB(p)->same_flow) + continue; + + iph2 = (struct iphdr *)(p->data + off); + /* The above works because, with the exception of the top + * (inner most) layer, we only aggregate pkts with the same + * hdr length so all the hdrs we'll need to verify will start + * at the same offset. + */ + if ((iph->protocol ^ iph2->protocol) | + ((__force u32)iph->saddr ^ (__force u32)iph2->saddr) | + ((__force u32)iph->daddr ^ (__force u32)iph2->daddr)) { + NAPI_GRO_CB(p)->same_flow = 0; + continue; + } + + /* All fields must match except length and checksum. */ + NAPI_GRO_CB(p)->flush |= + (iph->ttl ^ iph2->ttl) | + (iph->tos ^ iph2->tos) | + ((iph->frag_off ^ iph2->frag_off) & htons(IP_DF)); + + NAPI_GRO_CB(p)->flush |= flush; + + /* We need to store of the IP ID check to be included later + * when we can verify that this packet does in fact belong + * to a given flow. + */ + flush_id = (u16)(id - ntohs(iph2->id)); + + /* This bit of code makes it much easier for us to identify + * the cases where we are doing atomic vs non-atomic IP ID + * checks. Specifically an atomic check can return IP ID + * values 0 - 0xFFFF, while a non-atomic check can only + * return 0 or 0xFFFF. + */ + if (!NAPI_GRO_CB(p)->is_atomic || + !(iph->frag_off & htons(IP_DF))) { + flush_id ^= NAPI_GRO_CB(p)->count; + flush_id = flush_id ? 0xFFFF : 0; + } + + /* If the previous IP ID value was based on an atomic + * datagram we can overwrite the value and ignore it. + */ + if (NAPI_GRO_CB(skb)->is_atomic) + NAPI_GRO_CB(p)->flush_id = flush_id; + else + NAPI_GRO_CB(p)->flush_id |= flush_id; + } + + NAPI_GRO_CB(skb)->is_atomic = !!(iph->frag_off & htons(IP_DF)); + NAPI_GRO_CB(skb)->flush |= flush; + skb_set_network_header(skb, off); + /* The above will be needed by the transport layer if there is one + * immediately following this IP hdr. + */ + + /* Note : No need to call skb_gro_postpull_rcsum() here, + * as we already checked checksum over ipv4 header was 0 + */ + skb_gro_pull(skb, sizeof(*iph)); + skb_set_transport_header(skb, skb_gro_offset(skb)); + + pp = indirect_call_gro_receive(tcp4_gro_receive, udp4_gro_receive, + ops->callbacks.gro_receive, head, skb); + +out: + skb_gro_flush_final(skb, pp, flush); + + return pp; +} + +static struct sk_buff *ipip_gro_receive(struct list_head *head, + struct sk_buff *skb) +{ + if (NAPI_GRO_CB(skb)->encap_mark) { + NAPI_GRO_CB(skb)->flush = 1; + return NULL; + } + + NAPI_GRO_CB(skb)->encap_mark = 1; + + return inet_gro_receive(head, skb); +} + +#define SECONDS_PER_DAY 86400 + +/* inet_current_timestamp - Return IP network timestamp + * + * Return milliseconds since midnight in network byte order. + */ +__be32 inet_current_timestamp(void) +{ + u32 secs; + u32 msecs; + struct timespec64 ts; + + ktime_get_real_ts64(&ts); + + /* Get secs since midnight. */ + (void)div_u64_rem(ts.tv_sec, SECONDS_PER_DAY, &secs); + /* Convert to msecs. */ + msecs = secs * MSEC_PER_SEC; + /* Convert nsec to msec. */ + msecs += (u32)ts.tv_nsec / NSEC_PER_MSEC; + + /* Convert to network byte order. */ + return htonl(msecs); +} +EXPORT_SYMBOL(inet_current_timestamp); + +int inet_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len) +{ + if (sk->sk_family == AF_INET) + return ip_recv_error(sk, msg, len, addr_len); +#if IS_ENABLED(CONFIG_IPV6) + if (sk->sk_family == AF_INET6) + return pingv6_ops.ipv6_recv_error(sk, msg, len, addr_len); +#endif + return -EINVAL; +} +EXPORT_SYMBOL(inet_recv_error); + +int inet_gro_complete(struct sk_buff *skb, int nhoff) +{ + __be16 newlen = htons(skb->len - nhoff); + struct iphdr *iph = (struct iphdr *)(skb->data + nhoff); + const struct net_offload *ops; + int proto = iph->protocol; + int err = -ENOSYS; + + if (skb->encapsulation) { + skb_set_inner_protocol(skb, cpu_to_be16(ETH_P_IP)); + skb_set_inner_network_header(skb, nhoff); + } + + csum_replace2(&iph->check, iph->tot_len, newlen); + iph->tot_len = newlen; + + ops = rcu_dereference(inet_offloads[proto]); + if (WARN_ON(!ops || !ops->callbacks.gro_complete)) + goto out; + + /* Only need to add sizeof(*iph) to get to the next hdr below + * because any hdr with option will have been flushed in + * inet_gro_receive(). + */ + err = INDIRECT_CALL_2(ops->callbacks.gro_complete, + tcp4_gro_complete, udp4_gro_complete, + skb, nhoff + sizeof(*iph)); + +out: + return err; +} + +static int ipip_gro_complete(struct sk_buff *skb, int nhoff) +{ + skb->encapsulation = 1; + skb_shinfo(skb)->gso_type |= SKB_GSO_IPXIP4; + return inet_gro_complete(skb, nhoff); +} + +int inet_ctl_sock_create(struct sock **sk, unsigned short family, + unsigned short type, unsigned char protocol, + struct net *net) +{ + struct socket *sock; + int rc = sock_create_kern(net, family, type, protocol, &sock); + + if (rc == 0) { + *sk = sock->sk; + (*sk)->sk_allocation = GFP_ATOMIC; + /* + * Unhash it so that IP input processing does not even see it, + * we do not wish this socket to see incoming packets. + */ + (*sk)->sk_prot->unhash(*sk); + } + return rc; +} +EXPORT_SYMBOL_GPL(inet_ctl_sock_create); + +unsigned long snmp_fold_field(void __percpu *mib, int offt) +{ + unsigned long res = 0; + int i; + + for_each_possible_cpu(i) + res += snmp_get_cpu_field(mib, i, offt); + return res; +} +EXPORT_SYMBOL_GPL(snmp_fold_field); + +#if BITS_PER_LONG==32 + +u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offt, + size_t syncp_offset) +{ + void *bhptr; + struct u64_stats_sync *syncp; + u64 v; + unsigned int start; + + bhptr = per_cpu_ptr(mib, cpu); + syncp = (struct u64_stats_sync *)(bhptr + syncp_offset); + do { + start = u64_stats_fetch_begin_irq(syncp); + v = *(((u64 *)bhptr) + offt); + } while (u64_stats_fetch_retry_irq(syncp, start)); + + return v; +} +EXPORT_SYMBOL_GPL(snmp_get_cpu_field64); + +u64 snmp_fold_field64(void __percpu *mib, int offt, size_t syncp_offset) +{ + u64 res = 0; + int cpu; + + for_each_possible_cpu(cpu) { + res += snmp_get_cpu_field64(mib, cpu, offt, syncp_offset); + } + return res; +} +EXPORT_SYMBOL_GPL(snmp_fold_field64); +#endif + +#ifdef CONFIG_IP_MULTICAST +static const struct net_protocol igmp_protocol = { + .handler = igmp_rcv, +}; +#endif + +static const struct net_protocol tcp_protocol = { + .handler = tcp_v4_rcv, + .err_handler = tcp_v4_err, + .no_policy = 1, + .icmp_strict_tag_validation = 1, +}; + +static const struct net_protocol udp_protocol = { + .handler = udp_rcv, + .err_handler = udp_err, + .no_policy = 1, +}; + +static const struct net_protocol icmp_protocol = { + .handler = icmp_rcv, + .err_handler = icmp_err, + .no_policy = 1, +}; + +static __net_init int ipv4_mib_init_net(struct net *net) +{ + int i; + + net->mib.tcp_statistics = alloc_percpu(struct tcp_mib); + if (!net->mib.tcp_statistics) + goto err_tcp_mib; + net->mib.ip_statistics = alloc_percpu(struct ipstats_mib); + if (!net->mib.ip_statistics) + goto err_ip_mib; + + for_each_possible_cpu(i) { + struct ipstats_mib *af_inet_stats; + af_inet_stats = per_cpu_ptr(net->mib.ip_statistics, i); + u64_stats_init(&af_inet_stats->syncp); + } + + net->mib.net_statistics = alloc_percpu(struct linux_mib); + if (!net->mib.net_statistics) + goto err_net_mib; + net->mib.udp_statistics = alloc_percpu(struct udp_mib); + if (!net->mib.udp_statistics) + goto err_udp_mib; + net->mib.udplite_statistics = alloc_percpu(struct udp_mib); + if (!net->mib.udplite_statistics) + goto err_udplite_mib; + net->mib.icmp_statistics = alloc_percpu(struct icmp_mib); + if (!net->mib.icmp_statistics) + goto err_icmp_mib; + net->mib.icmpmsg_statistics = kzalloc(sizeof(struct icmpmsg_mib), + GFP_KERNEL); + if (!net->mib.icmpmsg_statistics) + goto err_icmpmsg_mib; + + tcp_mib_init(net); + return 0; + +err_icmpmsg_mib: + free_percpu(net->mib.icmp_statistics); +err_icmp_mib: + free_percpu(net->mib.udplite_statistics); +err_udplite_mib: + free_percpu(net->mib.udp_statistics); +err_udp_mib: + free_percpu(net->mib.net_statistics); +err_net_mib: + free_percpu(net->mib.ip_statistics); +err_ip_mib: + free_percpu(net->mib.tcp_statistics); +err_tcp_mib: + return -ENOMEM; +} + +static __net_exit void ipv4_mib_exit_net(struct net *net) +{ + kfree(net->mib.icmpmsg_statistics); + free_percpu(net->mib.icmp_statistics); + free_percpu(net->mib.udplite_statistics); + free_percpu(net->mib.udp_statistics); + free_percpu(net->mib.net_statistics); + free_percpu(net->mib.ip_statistics); + free_percpu(net->mib.tcp_statistics); +#ifdef CONFIG_MPTCP + /* allocated on demand, see mptcp_init_sock() */ + free_percpu(net->mib.mptcp_statistics); +#endif +} + +static __net_initdata struct pernet_operations ipv4_mib_ops = { + .init = ipv4_mib_init_net, + .exit = ipv4_mib_exit_net, +}; + +static int __init init_ipv4_mibs(void) +{ + return register_pernet_subsys(&ipv4_mib_ops); +} + +static __net_init int inet_init_net(struct net *net) +{ + /* + * Set defaults for local port range + */ + seqlock_init(&net->ipv4.ip_local_ports.lock); + net->ipv4.ip_local_ports.range[0] = 32768; + net->ipv4.ip_local_ports.range[1] = 60999; + + seqlock_init(&net->ipv4.ping_group_range.lock); + /* + * Sane defaults - nobody may create ping sockets. + * Boot scripts should set this to distro-specific group. + */ + net->ipv4.ping_group_range.range[0] = make_kgid(&init_user_ns, 1); + net->ipv4.ping_group_range.range[1] = make_kgid(&init_user_ns, 0); + + /* Default values for sysctl-controlled parameters. + * We set them here, in case sysctl is not compiled. + */ + net->ipv4.sysctl_ip_default_ttl = IPDEFTTL; + net->ipv4.sysctl_ip_fwd_update_priority = 1; + net->ipv4.sysctl_ip_dynaddr = 0; + net->ipv4.sysctl_ip_early_demux = 1; + net->ipv4.sysctl_udp_early_demux = 1; + net->ipv4.sysctl_tcp_early_demux = 1; + net->ipv4.sysctl_nexthop_compat_mode = 1; +#ifdef CONFIG_SYSCTL + net->ipv4.sysctl_ip_prot_sock = PROT_SOCK; +#endif + + /* Some igmp sysctl, whose values are always used */ + net->ipv4.sysctl_igmp_max_memberships = 20; + net->ipv4.sysctl_igmp_max_msf = 10; + /* IGMP reports for link-local multicast groups are enabled by default */ + net->ipv4.sysctl_igmp_llm_reports = 1; + net->ipv4.sysctl_igmp_qrv = 2; + + net->ipv4.sysctl_fib_notify_on_flag_change = 0; + + return 0; +} + +static __net_initdata struct pernet_operations af_inet_ops = { + .init = inet_init_net, +}; + +static int __init init_inet_pernet_ops(void) +{ + return register_pernet_subsys(&af_inet_ops); +} + +static int ipv4_proc_init(void); + +/* + * IP protocol layer initialiser + */ + +static struct packet_offload ip_packet_offload __read_mostly = { + .type = cpu_to_be16(ETH_P_IP), + .callbacks = { + .gso_segment = inet_gso_segment, + .gro_receive = inet_gro_receive, + .gro_complete = inet_gro_complete, + }, +}; + +static const struct net_offload ipip_offload = { + .callbacks = { + .gso_segment = ipip_gso_segment, + .gro_receive = ipip_gro_receive, + .gro_complete = ipip_gro_complete, + }, +}; + +static int __init ipip_offload_init(void) +{ + return inet_add_offload(&ipip_offload, IPPROTO_IPIP); +} + +static int __init ipv4_offload_init(void) +{ + /* + * Add offloads + */ + if (udpv4_offload_init() < 0) + pr_crit("%s: Cannot add UDP protocol offload\n", __func__); + if (tcpv4_offload_init() < 0) + pr_crit("%s: Cannot add TCP protocol offload\n", __func__); + if (ipip_offload_init() < 0) + pr_crit("%s: Cannot add IPIP protocol offload\n", __func__); + + dev_add_offload(&ip_packet_offload); + return 0; +} + +fs_initcall(ipv4_offload_init); + +static struct packet_type ip_packet_type __read_mostly = { + .type = cpu_to_be16(ETH_P_IP), + .func = ip_rcv, + .list_func = ip_list_rcv, +}; + +static int __init inet_init(void) +{ + struct inet_protosw *q; + struct list_head *r; + int rc; + + sock_skb_cb_check_size(sizeof(struct inet_skb_parm)); + + raw_hashinfo_init(&raw_v4_hashinfo); + + rc = proto_register(&tcp_prot, 1); + if (rc) + goto out; + + rc = proto_register(&udp_prot, 1); + if (rc) + goto out_unregister_tcp_proto; + + rc = proto_register(&raw_prot, 1); + if (rc) + goto out_unregister_udp_proto; + + rc = proto_register(&ping_prot, 1); + if (rc) + goto out_unregister_raw_proto; + + /* + * Tell SOCKET that we are alive... + */ + + (void)sock_register(&inet_family_ops); + +#ifdef CONFIG_SYSCTL + ip_static_sysctl_init(); +#endif + + /* + * Add all the base protocols. + */ + + if (inet_add_protocol(&icmp_protocol, IPPROTO_ICMP) < 0) + pr_crit("%s: Cannot add ICMP protocol\n", __func__); + if (inet_add_protocol(&udp_protocol, IPPROTO_UDP) < 0) + pr_crit("%s: Cannot add UDP protocol\n", __func__); + if (inet_add_protocol(&tcp_protocol, IPPROTO_TCP) < 0) + pr_crit("%s: Cannot add TCP protocol\n", __func__); +#ifdef CONFIG_IP_MULTICAST + if (inet_add_protocol(&igmp_protocol, IPPROTO_IGMP) < 0) + pr_crit("%s: Cannot add IGMP protocol\n", __func__); +#endif + + /* Register the socket-side information for inet_create. */ + for (r = &inetsw[0]; r < &inetsw[SOCK_MAX]; ++r) + INIT_LIST_HEAD(r); + + for (q = inetsw_array; q < &inetsw_array[INETSW_ARRAY_LEN]; ++q) + inet_register_protosw(q); + + /* + * Set the ARP module up + */ + + arp_init(); + + /* + * Set the IP module up + */ + + ip_init(); + + /* Initialise per-cpu ipv4 mibs */ + if (init_ipv4_mibs()) + panic("%s: Cannot init ipv4 mibs\n", __func__); + + /* Setup TCP slab cache for open requests. */ + tcp_init(); + + /* Setup UDP memory threshold */ + udp_init(); + + /* Add UDP-Lite (RFC 3828) */ + udplite4_register(); + + raw_init(); + + ping_init(); + + /* + * Set the ICMP layer up + */ + + if (icmp_init() < 0) + panic("Failed to create the ICMP control socket.\n"); + + /* + * Initialise the multicast router + */ +#if defined(CONFIG_IP_MROUTE) + if (ip_mr_init()) + pr_crit("%s: Cannot init ipv4 mroute\n", __func__); +#endif + + if (init_inet_pernet_ops()) + pr_crit("%s: Cannot init ipv4 inet pernet ops\n", __func__); + + ipv4_proc_init(); + + ipfrag_init(); + + dev_add_pack(&ip_packet_type); + + ip_tunnel_core_init(); + + rc = 0; +out: + return rc; +out_unregister_raw_proto: + proto_unregister(&raw_prot); +out_unregister_udp_proto: + proto_unregister(&udp_prot); +out_unregister_tcp_proto: + proto_unregister(&tcp_prot); + goto out; +} + +fs_initcall(inet_init); + +/* ------------------------------------------------------------------------ */ + +#ifdef CONFIG_PROC_FS +static int __init ipv4_proc_init(void) +{ + int rc = 0; + + if (raw_proc_init()) + goto out_raw; + if (tcp4_proc_init()) + goto out_tcp; + if (udp4_proc_init()) + goto out_udp; + if (ping_proc_init()) + goto out_ping; + if (ip_misc_proc_init()) + goto out_misc; +out: + return rc; +out_misc: + ping_proc_exit(); +out_ping: + udp4_proc_exit(); +out_udp: + tcp4_proc_exit(); +out_tcp: + raw_proc_exit(); +out_raw: + rc = -ENOMEM; + goto out; +} + +#else /* CONFIG_PROC_FS */ +static int __init ipv4_proc_init(void) +{ + return 0; +} +#endif /* CONFIG_PROC_FS */ |