| // SPDX-License-Identifier: GPL-2.0-or-later |
| /* |
| * UDP over IPv6 |
| * Linux INET6 implementation |
| * |
| * Authors: |
| * Pedro Roque <roque@di.fc.ul.pt> |
| * |
| * Based on linux/ipv4/udp.c |
| * |
| * Fixes: |
| * Hideaki YOSHIFUJI : sin6_scope_id support |
| * YOSHIFUJI Hideaki @USAGI and: Support IPV6_V6ONLY socket option, which |
| * Alexey Kuznetsov allow both IPv4 and IPv6 sockets to bind |
| * a single port at the same time. |
| * Kazunori MIYAZAWA @USAGI: change process style to use ip6_append_data |
| * YOSHIFUJI Hideaki @USAGI: convert /proc/net/udp6 to seq_file. |
| */ |
| |
| #include <linux/bpf-cgroup.h> |
| #include <linux/errno.h> |
| #include <linux/types.h> |
| #include <linux/socket.h> |
| #include <linux/sockios.h> |
| #include <linux/net.h> |
| #include <linux/in6.h> |
| #include <linux/netdevice.h> |
| #include <linux/if_arp.h> |
| #include <linux/ipv6.h> |
| #include <linux/icmpv6.h> |
| #include <linux/init.h> |
| #include <linux/module.h> |
| #include <linux/skbuff.h> |
| #include <linux/slab.h> |
| #include <linux/uaccess.h> |
| #include <linux/indirect_call_wrapper.h> |
| #include <trace/events/udp.h> |
| |
| #include <net/addrconf.h> |
| #include <net/ndisc.h> |
| #include <net/protocol.h> |
| #include <net/transp_v6.h> |
| #include <net/ip6_route.h> |
| #include <net/raw.h> |
| #include <net/seg6.h> |
| #include <net/tcp_states.h> |
| #include <net/ip6_checksum.h> |
| #include <net/ip6_tunnel.h> |
| #include <net/xfrm.h> |
| #include <net/inet_hashtables.h> |
| #include <net/inet6_hashtables.h> |
| #include <net/busy_poll.h> |
| #include <net/sock_reuseport.h> |
| #include <net/gro.h> |
| |
| #include <linux/proc_fs.h> |
| #include <linux/seq_file.h> |
| #include <trace/events/skb.h> |
| #include "udp_impl.h" |
| |
| static void udpv6_destruct_sock(struct sock *sk) |
| { |
| udp_destruct_common(sk); |
| inet6_sock_destruct(sk); |
| } |
| |
| int udpv6_init_sock(struct sock *sk) |
| { |
| udp_lib_init_sock(sk); |
| sk->sk_destruct = udpv6_destruct_sock; |
| set_bit(SOCK_SUPPORT_ZC, &sk->sk_socket->flags); |
| return 0; |
| } |
| |
| INDIRECT_CALLABLE_SCOPE |
| u32 udp6_ehashfn(const struct net *net, |
| const struct in6_addr *laddr, |
| const u16 lport, |
| const struct in6_addr *faddr, |
| const __be16 fport) |
| { |
| u32 lhash, fhash; |
| |
| net_get_random_once(&udp6_ehash_secret, |
| sizeof(udp6_ehash_secret)); |
| net_get_random_once(&udp_ipv6_hash_secret, |
| sizeof(udp_ipv6_hash_secret)); |
| |
| lhash = (__force u32)laddr->s6_addr32[3]; |
| fhash = __ipv6_addr_jhash(faddr, udp_ipv6_hash_secret); |
| |
| return __inet6_ehashfn(lhash, lport, fhash, fport, |
| udp6_ehash_secret + net_hash_mix(net)); |
| } |
| |
| int udp_v6_get_port(struct sock *sk, unsigned short snum) |
| { |
| unsigned int hash2_nulladdr = |
| ipv6_portaddr_hash(sock_net(sk), &in6addr_any, snum); |
| unsigned int hash2_partial = |
| ipv6_portaddr_hash(sock_net(sk), &sk->sk_v6_rcv_saddr, 0); |
| |
| /* precompute partial secondary hash */ |
| udp_sk(sk)->udp_portaddr_hash = hash2_partial; |
| return udp_lib_get_port(sk, snum, hash2_nulladdr); |
| } |
| |
| void udp_v6_rehash(struct sock *sk) |
| { |
| u16 new_hash = ipv6_portaddr_hash(sock_net(sk), |
| &sk->sk_v6_rcv_saddr, |
| inet_sk(sk)->inet_num); |
| |
| udp_lib_rehash(sk, new_hash); |
| } |
| |
| static int compute_score(struct sock *sk, struct net *net, |
| const struct in6_addr *saddr, __be16 sport, |
| const struct in6_addr *daddr, unsigned short hnum, |
| int dif, int sdif) |
| { |
| int bound_dev_if, score; |
| struct inet_sock *inet; |
| bool dev_match; |
| |
| if (!net_eq(sock_net(sk), net) || |
| udp_sk(sk)->udp_port_hash != hnum || |
| sk->sk_family != PF_INET6) |
| return -1; |
| |
| if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr)) |
| return -1; |
| |
| score = 0; |
| inet = inet_sk(sk); |
| |
| if (inet->inet_dport) { |
| if (inet->inet_dport != sport) |
| return -1; |
| score++; |
| } |
| |
| if (!ipv6_addr_any(&sk->sk_v6_daddr)) { |
| if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr)) |
| return -1; |
| score++; |
| } |
| |
| bound_dev_if = READ_ONCE(sk->sk_bound_dev_if); |
| dev_match = udp_sk_bound_dev_eq(net, bound_dev_if, dif, sdif); |
| if (!dev_match) |
| return -1; |
| if (bound_dev_if) |
| score++; |
| |
| if (READ_ONCE(sk->sk_incoming_cpu) == raw_smp_processor_id()) |
| score++; |
| |
| return score; |
| } |
| |
| /* called with rcu_read_lock() */ |
| static struct sock *udp6_lib_lookup2(struct net *net, |
| const struct in6_addr *saddr, __be16 sport, |
| const struct in6_addr *daddr, unsigned int hnum, |
| int dif, int sdif, struct udp_hslot *hslot2, |
| struct sk_buff *skb) |
| { |
| struct sock *sk, *result; |
| int score, badness; |
| bool need_rescore; |
| |
| result = NULL; |
| badness = -1; |
| udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) { |
| need_rescore = false; |
| rescore: |
| score = compute_score(need_rescore ? result : sk, net, saddr, |
| sport, daddr, hnum, dif, sdif); |
| if (score > badness) { |
| badness = score; |
| |
| if (need_rescore) |
| continue; |
| |
| if (sk->sk_state == TCP_ESTABLISHED) { |
| result = sk; |
| continue; |
| } |
| |
| result = inet6_lookup_reuseport(net, sk, skb, sizeof(struct udphdr), |
| saddr, sport, daddr, hnum, udp6_ehashfn); |
| if (!result) { |
| result = sk; |
| continue; |
| } |
| |
| /* Fall back to scoring if group has connections */ |
| if (!reuseport_has_conns(sk)) |
| return result; |
| |
| /* Reuseport logic returned an error, keep original score. */ |
| if (IS_ERR(result)) |
| continue; |
| |
| /* compute_score is too long of a function to be |
| * inlined, and calling it again here yields |
| * measureable overhead for some |
| * workloads. Work around it by jumping |
| * backwards to rescore 'result'. |
| */ |
| need_rescore = true; |
| goto rescore; |
| } |
| } |
| return result; |
| } |
| |
| /* rcu_read_lock() must be held */ |
| struct sock *__udp6_lib_lookup(struct net *net, |
| const struct in6_addr *saddr, __be16 sport, |
| const struct in6_addr *daddr, __be16 dport, |
| int dif, int sdif, struct udp_table *udptable, |
| struct sk_buff *skb) |
| { |
| unsigned short hnum = ntohs(dport); |
| unsigned int hash2, slot2; |
| struct udp_hslot *hslot2; |
| struct sock *result, *sk; |
| |
| hash2 = ipv6_portaddr_hash(net, daddr, hnum); |
| slot2 = hash2 & udptable->mask; |
| hslot2 = &udptable->hash2[slot2]; |
| |
| /* Lookup connected or non-wildcard sockets */ |
| result = udp6_lib_lookup2(net, saddr, sport, |
| daddr, hnum, dif, sdif, |
| hslot2, skb); |
| if (!IS_ERR_OR_NULL(result) && result->sk_state == TCP_ESTABLISHED) |
| goto done; |
| |
| /* Lookup redirect from BPF */ |
| if (static_branch_unlikely(&bpf_sk_lookup_enabled) && |
| udptable == net->ipv4.udp_table) { |
| sk = inet6_lookup_run_sk_lookup(net, IPPROTO_UDP, skb, sizeof(struct udphdr), |
| saddr, sport, daddr, hnum, dif, |
| udp6_ehashfn); |
| if (sk) { |
| result = sk; |
| goto done; |
| } |
| } |
| |
| /* Got non-wildcard socket or error on first lookup */ |
| if (result) |
| goto done; |
| |
| /* Lookup wildcard sockets */ |
| hash2 = ipv6_portaddr_hash(net, &in6addr_any, hnum); |
| slot2 = hash2 & udptable->mask; |
| hslot2 = &udptable->hash2[slot2]; |
| |
| result = udp6_lib_lookup2(net, saddr, sport, |
| &in6addr_any, hnum, dif, sdif, |
| hslot2, skb); |
| done: |
| if (IS_ERR(result)) |
| return NULL; |
| return result; |
| } |
| EXPORT_SYMBOL_GPL(__udp6_lib_lookup); |
| |
| static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb, |
| __be16 sport, __be16 dport, |
| struct udp_table *udptable) |
| { |
| const struct ipv6hdr *iph = ipv6_hdr(skb); |
| |
| return __udp6_lib_lookup(dev_net(skb->dev), &iph->saddr, sport, |
| &iph->daddr, dport, inet6_iif(skb), |
| inet6_sdif(skb), udptable, skb); |
| } |
| |
| struct sock *udp6_lib_lookup_skb(const struct sk_buff *skb, |
| __be16 sport, __be16 dport) |
| { |
| const u16 offset = NAPI_GRO_CB(skb)->network_offsets[skb->encapsulation]; |
| const struct ipv6hdr *iph = (struct ipv6hdr *)(skb->data + offset); |
| struct net *net = dev_net(skb->dev); |
| int iif, sdif; |
| |
| inet6_get_iif_sdif(skb, &iif, &sdif); |
| |
| return __udp6_lib_lookup(net, &iph->saddr, sport, |
| &iph->daddr, dport, iif, |
| sdif, net->ipv4.udp_table, NULL); |
| } |
| |
| /* Must be called under rcu_read_lock(). |
| * Does increment socket refcount. |
| */ |
| #if IS_ENABLED(CONFIG_NF_TPROXY_IPV6) || IS_ENABLED(CONFIG_NF_SOCKET_IPV6) |
| struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport, |
| const struct in6_addr *daddr, __be16 dport, int dif) |
| { |
| struct sock *sk; |
| |
| sk = __udp6_lib_lookup(net, saddr, sport, daddr, dport, |
| dif, 0, net->ipv4.udp_table, NULL); |
| if (sk && !refcount_inc_not_zero(&sk->sk_refcnt)) |
| sk = NULL; |
| return sk; |
| } |
| EXPORT_SYMBOL_GPL(udp6_lib_lookup); |
| #endif |
| |
| /* do not use the scratch area len for jumbogram: their length execeeds the |
| * scratch area space; note that the IP6CB flags is still in the first |
| * cacheline, so checking for jumbograms is cheap |
| */ |
| static int udp6_skb_len(struct sk_buff *skb) |
| { |
| return unlikely(inet6_is_jumbogram(skb)) ? skb->len : udp_skb_len(skb); |
| } |
| |
| /* |
| * This should be easy, if there is something there we |
| * return it, otherwise we block. |
| */ |
| |
| int udpv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, |
| int flags, int *addr_len) |
| { |
| struct ipv6_pinfo *np = inet6_sk(sk); |
| struct inet_sock *inet = inet_sk(sk); |
| struct sk_buff *skb; |
| unsigned int ulen, copied; |
| int off, err, peeking = flags & MSG_PEEK; |
| int is_udplite = IS_UDPLITE(sk); |
| struct udp_mib __percpu *mib; |
| bool checksum_valid = false; |
| int is_udp4; |
| |
| if (flags & MSG_ERRQUEUE) |
| return ipv6_recv_error(sk, msg, len, addr_len); |
| |
| if (np->rxpmtu && np->rxopt.bits.rxpmtu) |
| return ipv6_recv_rxpmtu(sk, msg, len, addr_len); |
| |
| try_again: |
| off = sk_peek_offset(sk, flags); |
| skb = __skb_recv_udp(sk, flags, &off, &err); |
| if (!skb) |
| return err; |
| |
| ulen = udp6_skb_len(skb); |
| copied = len; |
| if (copied > ulen - off) |
| copied = ulen - off; |
| else if (copied < ulen) |
| msg->msg_flags |= MSG_TRUNC; |
| |
| is_udp4 = (skb->protocol == htons(ETH_P_IP)); |
| mib = __UDPX_MIB(sk, is_udp4); |
| |
| /* |
| * If checksum is needed at all, try to do it while copying the |
| * data. If the data is truncated, or if we only want a partial |
| * coverage checksum (UDP-Lite), do it before the copy. |
| */ |
| |
| if (copied < ulen || peeking || |
| (is_udplite && UDP_SKB_CB(skb)->partial_cov)) { |
| checksum_valid = udp_skb_csum_unnecessary(skb) || |
| !__udp_lib_checksum_complete(skb); |
| if (!checksum_valid) |
| goto csum_copy_err; |
| } |
| |
| if (checksum_valid || udp_skb_csum_unnecessary(skb)) { |
| if (udp_skb_is_linear(skb)) |
| err = copy_linear_skb(skb, copied, off, &msg->msg_iter); |
| else |
| err = skb_copy_datagram_msg(skb, off, msg, copied); |
| } else { |
| err = skb_copy_and_csum_datagram_msg(skb, off, msg); |
| if (err == -EINVAL) |
| goto csum_copy_err; |
| } |
| if (unlikely(err)) { |
| if (!peeking) { |
| atomic_inc(&sk->sk_drops); |
| SNMP_INC_STATS(mib, UDP_MIB_INERRORS); |
| } |
| kfree_skb(skb); |
| return err; |
| } |
| if (!peeking) |
| SNMP_INC_STATS(mib, UDP_MIB_INDATAGRAMS); |
| |
| sock_recv_cmsgs(msg, sk, skb); |
| |
| /* Copy the address. */ |
| if (msg->msg_name) { |
| DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name); |
| sin6->sin6_family = AF_INET6; |
| sin6->sin6_port = udp_hdr(skb)->source; |
| sin6->sin6_flowinfo = 0; |
| |
| if (is_udp4) { |
| ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr, |
| &sin6->sin6_addr); |
| sin6->sin6_scope_id = 0; |
| } else { |
| sin6->sin6_addr = ipv6_hdr(skb)->saddr; |
| sin6->sin6_scope_id = |
| ipv6_iface_scope_id(&sin6->sin6_addr, |
| inet6_iif(skb)); |
| } |
| *addr_len = sizeof(*sin6); |
| |
| BPF_CGROUP_RUN_PROG_UDP6_RECVMSG_LOCK(sk, |
| (struct sockaddr *)sin6, |
| addr_len); |
| } |
| |
| if (udp_test_bit(GRO_ENABLED, sk)) |
| udp_cmsg_recv(msg, sk, skb); |
| |
| if (np->rxopt.all) |
| ip6_datagram_recv_common_ctl(sk, msg, skb); |
| |
| if (is_udp4) { |
| if (inet_cmsg_flags(inet)) |
| ip_cmsg_recv_offset(msg, sk, skb, |
| sizeof(struct udphdr), off); |
| } else { |
| if (np->rxopt.all) |
| ip6_datagram_recv_specific_ctl(sk, msg, skb); |
| } |
| |
| err = copied; |
| if (flags & MSG_TRUNC) |
| err = ulen; |
| |
| skb_consume_udp(sk, skb, peeking ? -err : err); |
| return err; |
| |
| csum_copy_err: |
| if (!__sk_queue_drop_skb(sk, &udp_sk(sk)->reader_queue, skb, flags, |
| udp_skb_destructor)) { |
| SNMP_INC_STATS(mib, UDP_MIB_CSUMERRORS); |
| SNMP_INC_STATS(mib, UDP_MIB_INERRORS); |
| } |
| kfree_skb(skb); |
| |
| /* starting over for a new packet, but check if we need to yield */ |
| cond_resched(); |
| msg->msg_flags &= ~MSG_TRUNC; |
| goto try_again; |
| } |
| |
| DECLARE_STATIC_KEY_FALSE(udpv6_encap_needed_key); |
| void udpv6_encap_enable(void) |
| { |
| static_branch_inc(&udpv6_encap_needed_key); |
| } |
| EXPORT_SYMBOL(udpv6_encap_enable); |
| |
| /* Handler for tunnels with arbitrary destination ports: no socket lookup, go |
| * through error handlers in encapsulations looking for a match. |
| */ |
| static int __udp6_lib_err_encap_no_sk(struct sk_buff *skb, |
| struct inet6_skb_parm *opt, |
| u8 type, u8 code, int offset, __be32 info) |
| { |
| int i; |
| |
| for (i = 0; i < MAX_IPTUN_ENCAP_OPS; i++) { |
| int (*handler)(struct sk_buff *skb, struct inet6_skb_parm *opt, |
| u8 type, u8 code, int offset, __be32 info); |
| const struct ip6_tnl_encap_ops *encap; |
| |
| encap = rcu_dereference(ip6tun_encaps[i]); |
| if (!encap) |
| continue; |
| handler = encap->err_handler; |
| if (handler && !handler(skb, opt, type, code, offset, info)) |
| return 0; |
| } |
| |
| return -ENOENT; |
| } |
| |
| /* Try to match ICMP errors to UDP tunnels by looking up a socket without |
| * reversing source and destination port: this will match tunnels that force the |
| * same destination port on both endpoints (e.g. VXLAN, GENEVE). Note that |
| * lwtunnels might actually break this assumption by being configured with |
| * different destination ports on endpoints, in this case we won't be able to |
| * trace ICMP messages back to them. |
| * |
| * If this doesn't match any socket, probe tunnels with arbitrary destination |
| * ports (e.g. FoU, GUE): there, the receiving socket is useless, as the port |
| * we've sent packets to won't necessarily match the local destination port. |
| * |
| * Then ask the tunnel implementation to match the error against a valid |
| * association. |
| * |
| * Return an error if we can't find a match, the socket if we need further |
| * processing, zero otherwise. |
| */ |
| static struct sock *__udp6_lib_err_encap(struct net *net, |
| const struct ipv6hdr *hdr, int offset, |
| struct udphdr *uh, |
| struct udp_table *udptable, |
| struct sock *sk, |
| struct sk_buff *skb, |
| struct inet6_skb_parm *opt, |
| u8 type, u8 code, __be32 info) |
| { |
| int (*lookup)(struct sock *sk, struct sk_buff *skb); |
| int network_offset, transport_offset; |
| struct udp_sock *up; |
| |
| network_offset = skb_network_offset(skb); |
| transport_offset = skb_transport_offset(skb); |
| |
| /* Network header needs to point to the outer IPv6 header inside ICMP */ |
| skb_reset_network_header(skb); |
| |
| /* Transport header needs to point to the UDP header */ |
| skb_set_transport_header(skb, offset); |
| |
| if (sk) { |
| up = udp_sk(sk); |
| |
| lookup = READ_ONCE(up->encap_err_lookup); |
| if (lookup && lookup(sk, skb)) |
| sk = NULL; |
| |
| goto out; |
| } |
| |
| sk = __udp6_lib_lookup(net, &hdr->daddr, uh->source, |
| &hdr->saddr, uh->dest, |
| inet6_iif(skb), 0, udptable, skb); |
| if (sk) { |
| up = udp_sk(sk); |
| |
| lookup = READ_ONCE(up->encap_err_lookup); |
| if (!lookup || lookup(sk, skb)) |
| sk = NULL; |
| } |
| |
| out: |
| if (!sk) { |
| sk = ERR_PTR(__udp6_lib_err_encap_no_sk(skb, opt, type, code, |
| offset, info)); |
| } |
| |
| skb_set_transport_header(skb, transport_offset); |
| skb_set_network_header(skb, network_offset); |
| |
| return sk; |
| } |
| |
| int __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt, |
| u8 type, u8 code, int offset, __be32 info, |
| struct udp_table *udptable) |
| { |
| struct ipv6_pinfo *np; |
| const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data; |
| const struct in6_addr *saddr = &hdr->saddr; |
| const struct in6_addr *daddr = seg6_get_daddr(skb, opt) ? : &hdr->daddr; |
| struct udphdr *uh = (struct udphdr *)(skb->data+offset); |
| bool tunnel = false; |
| struct sock *sk; |
| int harderr; |
| int err; |
| struct net *net = dev_net(skb->dev); |
| |
| sk = __udp6_lib_lookup(net, daddr, uh->dest, saddr, uh->source, |
| inet6_iif(skb), inet6_sdif(skb), udptable, NULL); |
| |
| if (!sk || READ_ONCE(udp_sk(sk)->encap_type)) { |
| /* No socket for error: try tunnels before discarding */ |
| if (static_branch_unlikely(&udpv6_encap_needed_key)) { |
| sk = __udp6_lib_err_encap(net, hdr, offset, uh, |
| udptable, sk, skb, |
| opt, type, code, info); |
| if (!sk) |
| return 0; |
| } else |
| sk = ERR_PTR(-ENOENT); |
| |
| if (IS_ERR(sk)) { |
| __ICMP6_INC_STATS(net, __in6_dev_get(skb->dev), |
| ICMP6_MIB_INERRORS); |
| return PTR_ERR(sk); |
| } |
| |
| tunnel = true; |
| } |
| |
| harderr = icmpv6_err_convert(type, code, &err); |
| np = inet6_sk(sk); |
| |
| if (type == ICMPV6_PKT_TOOBIG) { |
| if (!ip6_sk_accept_pmtu(sk)) |
| goto out; |
| ip6_sk_update_pmtu(skb, sk, info); |
| if (READ_ONCE(np->pmtudisc) != IPV6_PMTUDISC_DONT) |
| harderr = 1; |
| } |
| if (type == NDISC_REDIRECT) { |
| if (tunnel) { |
| ip6_redirect(skb, sock_net(sk), inet6_iif(skb), |
| READ_ONCE(sk->sk_mark), sk->sk_uid); |
| } else { |
| ip6_sk_redirect(skb, sk); |
| } |
| goto out; |
| } |
| |
| /* Tunnels don't have an application socket: don't pass errors back */ |
| if (tunnel) { |
| if (udp_sk(sk)->encap_err_rcv) |
| udp_sk(sk)->encap_err_rcv(sk, skb, err, uh->dest, |
| ntohl(info), (u8 *)(uh+1)); |
| goto out; |
| } |
| |
| if (!inet6_test_bit(RECVERR6, sk)) { |
| if (!harderr || sk->sk_state != TCP_ESTABLISHED) |
| goto out; |
| } else { |
| ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1)); |
| } |
| |
| sk->sk_err = err; |
| sk_error_report(sk); |
| out: |
| return 0; |
| } |
| |
| static int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) |
| { |
| int rc; |
| |
| if (!ipv6_addr_any(&sk->sk_v6_daddr)) { |
| sock_rps_save_rxhash(sk, skb); |
| sk_mark_napi_id(sk, skb); |
| sk_incoming_cpu_update(sk); |
| } else { |
| sk_mark_napi_id_once(sk, skb); |
| } |
| |
| rc = __udp_enqueue_schedule_skb(sk, skb); |
| if (rc < 0) { |
| int is_udplite = IS_UDPLITE(sk); |
| enum skb_drop_reason drop_reason; |
| |
| /* Note that an ENOMEM error is charged twice */ |
| if (rc == -ENOMEM) { |
| UDP6_INC_STATS(sock_net(sk), |
| UDP_MIB_RCVBUFERRORS, is_udplite); |
| drop_reason = SKB_DROP_REASON_SOCKET_RCVBUFF; |
| } else { |
| UDP6_INC_STATS(sock_net(sk), |
| UDP_MIB_MEMERRORS, is_udplite); |
| drop_reason = SKB_DROP_REASON_PROTO_MEM; |
| } |
| UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite); |
| trace_udp_fail_queue_rcv_skb(rc, sk, skb); |
| sk_skb_reason_drop(sk, skb, drop_reason); |
| return -1; |
| } |
| |
| return 0; |
| } |
| |
| static __inline__ int udpv6_err(struct sk_buff *skb, |
| struct inet6_skb_parm *opt, u8 type, |
| u8 code, int offset, __be32 info) |
| { |
| return __udp6_lib_err(skb, opt, type, code, offset, info, |
| dev_net(skb->dev)->ipv4.udp_table); |
| } |
| |
| static int udpv6_queue_rcv_one_skb(struct sock *sk, struct sk_buff *skb) |
| { |
| enum skb_drop_reason drop_reason = SKB_DROP_REASON_NOT_SPECIFIED; |
| struct udp_sock *up = udp_sk(sk); |
| int is_udplite = IS_UDPLITE(sk); |
| |
| if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) { |
| drop_reason = SKB_DROP_REASON_XFRM_POLICY; |
| goto drop; |
| } |
| nf_reset_ct(skb); |
| |
| if (static_branch_unlikely(&udpv6_encap_needed_key) && |
| READ_ONCE(up->encap_type)) { |
| int (*encap_rcv)(struct sock *sk, struct sk_buff *skb); |
| |
| /* |
| * This is an encapsulation socket so pass the skb to |
| * the socket's udp_encap_rcv() hook. Otherwise, just |
| * fall through and pass this up the UDP socket. |
| * up->encap_rcv() returns the following value: |
| * =0 if skb was successfully passed to the encap |
| * handler or was discarded by it. |
| * >0 if skb should be passed on to UDP. |
| * <0 if skb should be resubmitted as proto -N |
| */ |
| |
| /* if we're overly short, let UDP handle it */ |
| encap_rcv = READ_ONCE(up->encap_rcv); |
| if (encap_rcv) { |
| int ret; |
| |
| /* Verify checksum before giving to encap */ |
| if (udp_lib_checksum_complete(skb)) |
| goto csum_error; |
| |
| ret = encap_rcv(sk, skb); |
| if (ret <= 0) { |
| __UDP6_INC_STATS(sock_net(sk), |
| UDP_MIB_INDATAGRAMS, |
| is_udplite); |
| return -ret; |
| } |
| } |
| |
| /* FALLTHROUGH -- it's a UDP Packet */ |
| } |
| |
| /* |
| * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c). |
| */ |
| if (udp_test_bit(UDPLITE_RECV_CC, sk) && UDP_SKB_CB(skb)->partial_cov) { |
| u16 pcrlen = READ_ONCE(up->pcrlen); |
| |
| if (pcrlen == 0) { /* full coverage was set */ |
| net_dbg_ratelimited("UDPLITE6: partial coverage %d while full coverage %d requested\n", |
| UDP_SKB_CB(skb)->cscov, skb->len); |
| goto drop; |
| } |
| if (UDP_SKB_CB(skb)->cscov < pcrlen) { |
| net_dbg_ratelimited("UDPLITE6: coverage %d too small, need min %d\n", |
| UDP_SKB_CB(skb)->cscov, pcrlen); |
| goto drop; |
| } |
| } |
| |
| prefetch(&sk->sk_rmem_alloc); |
| if (rcu_access_pointer(sk->sk_filter) && |
| udp_lib_checksum_complete(skb)) |
| goto csum_error; |
| |
| if (sk_filter_trim_cap(sk, skb, sizeof(struct udphdr))) { |
| drop_reason = SKB_DROP_REASON_SOCKET_FILTER; |
| goto drop; |
| } |
| |
| udp_csum_pull_header(skb); |
| |
| skb_dst_drop(skb); |
| |
| return __udpv6_queue_rcv_skb(sk, skb); |
| |
| csum_error: |
| drop_reason = SKB_DROP_REASON_UDP_CSUM; |
| __UDP6_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite); |
| drop: |
| __UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite); |
| atomic_inc(&sk->sk_drops); |
| sk_skb_reason_drop(sk, skb, drop_reason); |
| return -1; |
| } |
| |
| static int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) |
| { |
| struct sk_buff *next, *segs; |
| int ret; |
| |
| if (likely(!udp_unexpected_gso(sk, skb))) |
| return udpv6_queue_rcv_one_skb(sk, skb); |
| |
| __skb_push(skb, -skb_mac_offset(skb)); |
| segs = udp_rcv_segment(sk, skb, false); |
| skb_list_walk_safe(segs, skb, next) { |
| __skb_pull(skb, skb_transport_offset(skb)); |
| |
| udp_post_segment_fix_csum(skb); |
| ret = udpv6_queue_rcv_one_skb(sk, skb); |
| if (ret > 0) |
| ip6_protocol_deliver_rcu(dev_net(skb->dev), skb, ret, |
| true); |
| } |
| return 0; |
| } |
| |
| static bool __udp_v6_is_mcast_sock(struct net *net, const struct sock *sk, |
| __be16 loc_port, const struct in6_addr *loc_addr, |
| __be16 rmt_port, const struct in6_addr *rmt_addr, |
| int dif, int sdif, unsigned short hnum) |
| { |
| const struct inet_sock *inet = inet_sk(sk); |
| |
| if (!net_eq(sock_net(sk), net)) |
| return false; |
| |
| if (udp_sk(sk)->udp_port_hash != hnum || |
| sk->sk_family != PF_INET6 || |
| (inet->inet_dport && inet->inet_dport != rmt_port) || |
| (!ipv6_addr_any(&sk->sk_v6_daddr) && |
| !ipv6_addr_equal(&sk->sk_v6_daddr, rmt_addr)) || |
| !udp_sk_bound_dev_eq(net, READ_ONCE(sk->sk_bound_dev_if), dif, sdif) || |
| (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) && |
| !ipv6_addr_equal(&sk->sk_v6_rcv_saddr, loc_addr))) |
| return false; |
| if (!inet6_mc_check(sk, loc_addr, rmt_addr)) |
| return false; |
| return true; |
| } |
| |
| static void udp6_csum_zero_error(struct sk_buff *skb) |
| { |
| /* RFC 2460 section 8.1 says that we SHOULD log |
| * this error. Well, it is reasonable. |
| */ |
| net_dbg_ratelimited("IPv6: udp checksum is 0 for [%pI6c]:%u->[%pI6c]:%u\n", |
| &ipv6_hdr(skb)->saddr, ntohs(udp_hdr(skb)->source), |
| &ipv6_hdr(skb)->daddr, ntohs(udp_hdr(skb)->dest)); |
| } |
| |
| /* |
| * Note: called only from the BH handler context, |
| * so we don't need to lock the hashes. |
| */ |
| static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb, |
| const struct in6_addr *saddr, const struct in6_addr *daddr, |
| struct udp_table *udptable, int proto) |
| { |
| struct sock *sk, *first = NULL; |
| const struct udphdr *uh = udp_hdr(skb); |
| unsigned short hnum = ntohs(uh->dest); |
| struct udp_hslot *hslot = udp_hashslot(udptable, net, hnum); |
| unsigned int offset = offsetof(typeof(*sk), sk_node); |
| unsigned int hash2 = 0, hash2_any = 0, use_hash2 = (hslot->count > 10); |
| int dif = inet6_iif(skb); |
| int sdif = inet6_sdif(skb); |
| struct hlist_node *node; |
| struct sk_buff *nskb; |
| |
| if (use_hash2) { |
| hash2_any = ipv6_portaddr_hash(net, &in6addr_any, hnum) & |
| udptable->mask; |
| hash2 = ipv6_portaddr_hash(net, daddr, hnum) & udptable->mask; |
| start_lookup: |
| hslot = &udptable->hash2[hash2]; |
| offset = offsetof(typeof(*sk), __sk_common.skc_portaddr_node); |
| } |
| |
| sk_for_each_entry_offset_rcu(sk, node, &hslot->head, offset) { |
| if (!__udp_v6_is_mcast_sock(net, sk, uh->dest, daddr, |
| uh->source, saddr, dif, sdif, |
| hnum)) |
| continue; |
| /* If zero checksum and no_check is not on for |
| * the socket then skip it. |
| */ |
| if (!uh->check && !udp_get_no_check6_rx(sk)) |
| continue; |
| if (!first) { |
| first = sk; |
| continue; |
| } |
| nskb = skb_clone(skb, GFP_ATOMIC); |
| if (unlikely(!nskb)) { |
| atomic_inc(&sk->sk_drops); |
| __UDP6_INC_STATS(net, UDP_MIB_RCVBUFERRORS, |
| IS_UDPLITE(sk)); |
| __UDP6_INC_STATS(net, UDP_MIB_INERRORS, |
| IS_UDPLITE(sk)); |
| continue; |
| } |
| |
| if (udpv6_queue_rcv_skb(sk, nskb) > 0) |
| consume_skb(nskb); |
| } |
| |
| /* Also lookup *:port if we are using hash2 and haven't done so yet. */ |
| if (use_hash2 && hash2 != hash2_any) { |
| hash2 = hash2_any; |
| goto start_lookup; |
| } |
| |
| if (first) { |
| if (udpv6_queue_rcv_skb(first, skb) > 0) |
| consume_skb(skb); |
| } else { |
| kfree_skb(skb); |
| __UDP6_INC_STATS(net, UDP_MIB_IGNOREDMULTI, |
| proto == IPPROTO_UDPLITE); |
| } |
| return 0; |
| } |
| |
| static void udp6_sk_rx_dst_set(struct sock *sk, struct dst_entry *dst) |
| { |
| if (udp_sk_rx_dst_set(sk, dst)) |
| sk->sk_rx_dst_cookie = rt6_get_cookie(dst_rt6_info(dst)); |
| } |
| |
| /* wrapper for udp_queue_rcv_skb tacking care of csum conversion and |
| * return code conversion for ip layer consumption |
| */ |
| static int udp6_unicast_rcv_skb(struct sock *sk, struct sk_buff *skb, |
| struct udphdr *uh) |
| { |
| int ret; |
| |
| if (inet_get_convert_csum(sk) && uh->check && !IS_UDPLITE(sk)) |
| skb_checksum_try_convert(skb, IPPROTO_UDP, ip6_compute_pseudo); |
| |
| ret = udpv6_queue_rcv_skb(sk, skb); |
| |
| /* a return value > 0 means to resubmit the input */ |
| if (ret > 0) |
| return ret; |
| return 0; |
| } |
| |
| int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, |
| int proto) |
| { |
| enum skb_drop_reason reason = SKB_DROP_REASON_NOT_SPECIFIED; |
| const struct in6_addr *saddr, *daddr; |
| struct net *net = dev_net(skb->dev); |
| struct sock *sk = NULL; |
| struct udphdr *uh; |
| bool refcounted; |
| u32 ulen = 0; |
| |
| if (!pskb_may_pull(skb, sizeof(struct udphdr))) |
| goto discard; |
| |
| saddr = &ipv6_hdr(skb)->saddr; |
| daddr = &ipv6_hdr(skb)->daddr; |
| uh = udp_hdr(skb); |
| |
| ulen = ntohs(uh->len); |
| if (ulen > skb->len) |
| goto short_packet; |
| |
| if (proto == IPPROTO_UDP) { |
| /* UDP validates ulen. */ |
| |
| /* Check for jumbo payload */ |
| if (ulen == 0) |
| ulen = skb->len; |
| |
| if (ulen < sizeof(*uh)) |
| goto short_packet; |
| |
| if (ulen < skb->len) { |
| if (pskb_trim_rcsum(skb, ulen)) |
| goto short_packet; |
| saddr = &ipv6_hdr(skb)->saddr; |
| daddr = &ipv6_hdr(skb)->daddr; |
| uh = udp_hdr(skb); |
| } |
| } |
| |
| if (udp6_csum_init(skb, uh, proto)) |
| goto csum_error; |
| |
| /* Check if the socket is already available, e.g. due to early demux */ |
| sk = inet6_steal_sock(net, skb, sizeof(struct udphdr), saddr, uh->source, daddr, uh->dest, |
| &refcounted, udp6_ehashfn); |
| if (IS_ERR(sk)) |
| goto no_sk; |
| |
| if (sk) { |
| struct dst_entry *dst = skb_dst(skb); |
| int ret; |
| |
| if (unlikely(rcu_dereference(sk->sk_rx_dst) != dst)) |
| udp6_sk_rx_dst_set(sk, dst); |
| |
| if (!uh->check && !udp_get_no_check6_rx(sk)) { |
| if (refcounted) |
| sock_put(sk); |
| goto report_csum_error; |
| } |
| |
| ret = udp6_unicast_rcv_skb(sk, skb, uh); |
| if (refcounted) |
| sock_put(sk); |
| return ret; |
| } |
| |
| /* |
| * Multicast receive code |
| */ |
| if (ipv6_addr_is_multicast(daddr)) |
| return __udp6_lib_mcast_deliver(net, skb, |
| saddr, daddr, udptable, proto); |
| |
| /* Unicast */ |
| sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable); |
| if (sk) { |
| if (!uh->check && !udp_get_no_check6_rx(sk)) |
| goto report_csum_error; |
| return udp6_unicast_rcv_skb(sk, skb, uh); |
| } |
| no_sk: |
| reason = SKB_DROP_REASON_NO_SOCKET; |
| |
| if (!uh->check) |
| goto report_csum_error; |
| |
| if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) |
| goto discard; |
| nf_reset_ct(skb); |
| |
| if (udp_lib_checksum_complete(skb)) |
| goto csum_error; |
| |
| __UDP6_INC_STATS(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE); |
| icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0); |
| |
| sk_skb_reason_drop(sk, skb, reason); |
| return 0; |
| |
| short_packet: |
| if (reason == SKB_DROP_REASON_NOT_SPECIFIED) |
| reason = SKB_DROP_REASON_PKT_TOO_SMALL; |
| net_dbg_ratelimited("UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n", |
| proto == IPPROTO_UDPLITE ? "-Lite" : "", |
| saddr, ntohs(uh->source), |
| ulen, skb->len, |
| daddr, ntohs(uh->dest)); |
| goto discard; |
| |
| report_csum_error: |
| udp6_csum_zero_error(skb); |
| csum_error: |
| if (reason == SKB_DROP_REASON_NOT_SPECIFIED) |
| reason = SKB_DROP_REASON_UDP_CSUM; |
| __UDP6_INC_STATS(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE); |
| discard: |
| __UDP6_INC_STATS(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE); |
| sk_skb_reason_drop(sk, skb, reason); |
| return 0; |
| } |
| |
| |
| static struct sock *__udp6_lib_demux_lookup(struct net *net, |
| __be16 loc_port, const struct in6_addr *loc_addr, |
| __be16 rmt_port, const struct in6_addr *rmt_addr, |
| int dif, int sdif) |
| { |
| struct udp_table *udptable = net->ipv4.udp_table; |
| unsigned short hnum = ntohs(loc_port); |
| unsigned int hash2, slot2; |
| struct udp_hslot *hslot2; |
| __portpair ports; |
| struct sock *sk; |
| |
| hash2 = ipv6_portaddr_hash(net, loc_addr, hnum); |
| slot2 = hash2 & udptable->mask; |
| hslot2 = &udptable->hash2[slot2]; |
| ports = INET_COMBINED_PORTS(rmt_port, hnum); |
| |
| udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) { |
| if (sk->sk_state == TCP_ESTABLISHED && |
| inet6_match(net, sk, rmt_addr, loc_addr, ports, dif, sdif)) |
| return sk; |
| /* Only check first socket in chain */ |
| break; |
| } |
| return NULL; |
| } |
| |
| void udp_v6_early_demux(struct sk_buff *skb) |
| { |
| struct net *net = dev_net(skb->dev); |
| const struct udphdr *uh; |
| struct sock *sk; |
| struct dst_entry *dst; |
| int dif = skb->dev->ifindex; |
| int sdif = inet6_sdif(skb); |
| |
| if (!pskb_may_pull(skb, skb_transport_offset(skb) + |
| sizeof(struct udphdr))) |
| return; |
| |
| uh = udp_hdr(skb); |
| |
| if (skb->pkt_type == PACKET_HOST) |
| sk = __udp6_lib_demux_lookup(net, uh->dest, |
| &ipv6_hdr(skb)->daddr, |
| uh->source, &ipv6_hdr(skb)->saddr, |
| dif, sdif); |
| else |
| return; |
| |
| if (!sk) |
| return; |
| |
| skb->sk = sk; |
| DEBUG_NET_WARN_ON_ONCE(sk_is_refcounted(sk)); |
| skb->destructor = sock_pfree; |
| dst = rcu_dereference(sk->sk_rx_dst); |
| |
| if (dst) |
| dst = dst_check(dst, sk->sk_rx_dst_cookie); |
| if (dst) { |
| /* set noref for now. |
| * any place which wants to hold dst has to call |
| * dst_hold_safe() |
| */ |
| skb_dst_set_noref(skb, dst); |
| } |
| } |
| |
| INDIRECT_CALLABLE_SCOPE int udpv6_rcv(struct sk_buff *skb) |
| { |
| return __udp6_lib_rcv(skb, dev_net(skb->dev)->ipv4.udp_table, IPPROTO_UDP); |
| } |
| |
| /* |
| * Throw away all pending data and cancel the corking. Socket is locked. |
| */ |
| static void udp_v6_flush_pending_frames(struct sock *sk) |
| { |
| struct udp_sock *up = udp_sk(sk); |
| |
| if (up->pending == AF_INET) |
| udp_flush_pending_frames(sk); |
| else if (up->pending) { |
| up->len = 0; |
| WRITE_ONCE(up->pending, 0); |
| ip6_flush_pending_frames(sk); |
| } |
| } |
| |
| static int udpv6_pre_connect(struct sock *sk, struct sockaddr *uaddr, |
| int addr_len) |
| { |
| if (addr_len < offsetofend(struct sockaddr, sa_family)) |
| return -EINVAL; |
| /* The following checks are replicated from __ip6_datagram_connect() |
| * and intended to prevent BPF program called below from accessing |
| * bytes that are out of the bound specified by user in addr_len. |
| */ |
| if (uaddr->sa_family == AF_INET) { |
| if (ipv6_only_sock(sk)) |
| return -EAFNOSUPPORT; |
| return udp_pre_connect(sk, uaddr, addr_len); |
| } |
| |
| if (addr_len < SIN6_LEN_RFC2133) |
| return -EINVAL; |
| |
| return BPF_CGROUP_RUN_PROG_INET6_CONNECT_LOCK(sk, uaddr, &addr_len); |
| } |
| |
| /** |
| * udp6_hwcsum_outgoing - handle outgoing HW checksumming |
| * @sk: socket we are sending on |
| * @skb: sk_buff containing the filled-in UDP header |
| * (checksum field must be zeroed out) |
| * @saddr: source address |
| * @daddr: destination address |
| * @len: length of packet |
| */ |
| static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb, |
| const struct in6_addr *saddr, |
| const struct in6_addr *daddr, int len) |
| { |
| unsigned int offset; |
| struct udphdr *uh = udp_hdr(skb); |
| struct sk_buff *frags = skb_shinfo(skb)->frag_list; |
| __wsum csum = 0; |
| |
| if (!frags) { |
| /* Only one fragment on the socket. */ |
| skb->csum_start = skb_transport_header(skb) - skb->head; |
| skb->csum_offset = offsetof(struct udphdr, check); |
| uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0); |
| } else { |
| /* |
| * HW-checksum won't work as there are two or more |
| * fragments on the socket so that all csums of sk_buffs |
| * should be together |
| */ |
| offset = skb_transport_offset(skb); |
| skb->csum = skb_checksum(skb, offset, skb->len - offset, 0); |
| csum = skb->csum; |
| |
| skb->ip_summed = CHECKSUM_NONE; |
| |
| do { |
| csum = csum_add(csum, frags->csum); |
| } while ((frags = frags->next)); |
| |
| uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, |
| csum); |
| if (uh->check == 0) |
| uh->check = CSUM_MANGLED_0; |
| } |
| } |
| |
| /* |
| * Sending |
| */ |
| |
| static int udp_v6_send_skb(struct sk_buff *skb, struct flowi6 *fl6, |
| struct inet_cork *cork) |
| { |
| struct sock *sk = skb->sk; |
| struct udphdr *uh; |
| int err = 0; |
| int is_udplite = IS_UDPLITE(sk); |
| __wsum csum = 0; |
| int offset = skb_transport_offset(skb); |
| int len = skb->len - offset; |
| int datalen = len - sizeof(*uh); |
| |
| /* |
| * Create a UDP header |
| */ |
| uh = udp_hdr(skb); |
| uh->source = fl6->fl6_sport; |
| uh->dest = fl6->fl6_dport; |
| uh->len = htons(len); |
| uh->check = 0; |
| |
| if (cork->gso_size) { |
| const int hlen = skb_network_header_len(skb) + |
| sizeof(struct udphdr); |
| |
| if (hlen + cork->gso_size > cork->fragsize) { |
| kfree_skb(skb); |
| return -EINVAL; |
| } |
| if (datalen > cork->gso_size * UDP_MAX_SEGMENTS) { |
| kfree_skb(skb); |
| return -EINVAL; |
| } |
| if (udp_get_no_check6_tx(sk)) { |
| kfree_skb(skb); |
| return -EINVAL; |
| } |
| if (is_udplite || dst_xfrm(skb_dst(skb))) { |
| kfree_skb(skb); |
| return -EIO; |
| } |
| |
| if (datalen > cork->gso_size) { |
| skb_shinfo(skb)->gso_size = cork->gso_size; |
| skb_shinfo(skb)->gso_type = SKB_GSO_UDP_L4; |
| skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(datalen, |
| cork->gso_size); |
| } |
| goto csum_partial; |
| } |
| |
| if (is_udplite) |
| csum = udplite_csum(skb); |
| else if (udp_get_no_check6_tx(sk)) { /* UDP csum disabled */ |
| skb->ip_summed = CHECKSUM_NONE; |
| goto send; |
| } else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */ |
| csum_partial: |
| udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr, len); |
| goto send; |
| } else |
| csum = udp_csum(skb); |
| |
| /* add protocol-dependent pseudo-header */ |
| uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr, |
| len, fl6->flowi6_proto, csum); |
| if (uh->check == 0) |
| uh->check = CSUM_MANGLED_0; |
| |
| send: |
| err = ip6_send_skb(skb); |
| if (err) { |
| if (err == -ENOBUFS && !inet6_test_bit(RECVERR6, sk)) { |
| UDP6_INC_STATS(sock_net(sk), |
| UDP_MIB_SNDBUFERRORS, is_udplite); |
| err = 0; |
| } |
| } else { |
| UDP6_INC_STATS(sock_net(sk), |
| UDP_MIB_OUTDATAGRAMS, is_udplite); |
| } |
| return err; |
| } |
| |
| static int udp_v6_push_pending_frames(struct sock *sk) |
| { |
| struct sk_buff *skb; |
| struct udp_sock *up = udp_sk(sk); |
| int err = 0; |
| |
| if (up->pending == AF_INET) |
| return udp_push_pending_frames(sk); |
| |
| skb = ip6_finish_skb(sk); |
| if (!skb) |
| goto out; |
| |
| err = udp_v6_send_skb(skb, &inet_sk(sk)->cork.fl.u.ip6, |
| &inet_sk(sk)->cork.base); |
| out: |
| up->len = 0; |
| WRITE_ONCE(up->pending, 0); |
| return err; |
| } |
| |
| int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) |
| { |
| struct ipv6_txoptions opt_space; |
| struct udp_sock *up = udp_sk(sk); |
| struct inet_sock *inet = inet_sk(sk); |
| struct ipv6_pinfo *np = inet6_sk(sk); |
| DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name); |
| struct in6_addr *daddr, *final_p, final; |
| struct ipv6_txoptions *opt = NULL; |
| struct ipv6_txoptions *opt_to_free = NULL; |
| struct ip6_flowlabel *flowlabel = NULL; |
| struct inet_cork_full cork; |
| struct flowi6 *fl6 = &cork.fl.u.ip6; |
| struct dst_entry *dst; |
| struct ipcm6_cookie ipc6; |
| int addr_len = msg->msg_namelen; |
| bool connected = false; |
| int ulen = len; |
| int corkreq = udp_test_bit(CORK, sk) || msg->msg_flags & MSG_MORE; |
| int err; |
| int is_udplite = IS_UDPLITE(sk); |
| int (*getfrag)(void *, char *, int, int, int, struct sk_buff *); |
| |
| ipcm6_init(&ipc6); |
| ipc6.gso_size = READ_ONCE(up->gso_size); |
| ipc6.sockc.tsflags = READ_ONCE(sk->sk_tsflags); |
| ipc6.sockc.mark = READ_ONCE(sk->sk_mark); |
| |
| /* destination address check */ |
| if (sin6) { |
| if (addr_len < offsetof(struct sockaddr, sa_data)) |
| return -EINVAL; |
| |
| switch (sin6->sin6_family) { |
| case AF_INET6: |
| if (addr_len < SIN6_LEN_RFC2133) |
| return -EINVAL; |
| daddr = &sin6->sin6_addr; |
| if (ipv6_addr_any(daddr) && |
| ipv6_addr_v4mapped(&np->saddr)) |
| ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK), |
| daddr); |
| break; |
| case AF_INET: |
| goto do_udp_sendmsg; |
| case AF_UNSPEC: |
| msg->msg_name = sin6 = NULL; |
| msg->msg_namelen = addr_len = 0; |
| daddr = NULL; |
| break; |
| default: |
| return -EINVAL; |
| } |
| } else if (!READ_ONCE(up->pending)) { |
| if (sk->sk_state != TCP_ESTABLISHED) |
| return -EDESTADDRREQ; |
| daddr = &sk->sk_v6_daddr; |
| } else |
| daddr = NULL; |
| |
| if (daddr) { |
| if (ipv6_addr_v4mapped(daddr)) { |
| struct sockaddr_in sin; |
| sin.sin_family = AF_INET; |
| sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport; |
| sin.sin_addr.s_addr = daddr->s6_addr32[3]; |
| msg->msg_name = &sin; |
| msg->msg_namelen = sizeof(sin); |
| do_udp_sendmsg: |
| err = ipv6_only_sock(sk) ? |
| -ENETUNREACH : udp_sendmsg(sk, msg, len); |
| msg->msg_name = sin6; |
| msg->msg_namelen = addr_len; |
| return err; |
| } |
| } |
| |
| /* Rough check on arithmetic overflow, |
| better check is made in ip6_append_data(). |
| */ |
| if (len > INT_MAX - sizeof(struct udphdr)) |
| return -EMSGSIZE; |
| |
| getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag; |
| if (READ_ONCE(up->pending)) { |
| if (READ_ONCE(up->pending) == AF_INET) |
| return udp_sendmsg(sk, msg, len); |
| /* |
| * There are pending frames. |
| * The socket lock must be held while it's corked. |
| */ |
| lock_sock(sk); |
| if (likely(up->pending)) { |
| if (unlikely(up->pending != AF_INET6)) { |
| release_sock(sk); |
| return -EAFNOSUPPORT; |
| } |
| dst = NULL; |
| goto do_append_data; |
| } |
| release_sock(sk); |
| } |
| ulen += sizeof(struct udphdr); |
| |
| memset(fl6, 0, sizeof(*fl6)); |
| |
| if (sin6) { |
| if (sin6->sin6_port == 0) |
| return -EINVAL; |
| |
| fl6->fl6_dport = sin6->sin6_port; |
| daddr = &sin6->sin6_addr; |
| |
| if (inet6_test_bit(SNDFLOW, sk)) { |
| fl6->flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK; |
| if (fl6->flowlabel & IPV6_FLOWLABEL_MASK) { |
| flowlabel = fl6_sock_lookup(sk, fl6->flowlabel); |
| if (IS_ERR(flowlabel)) |
| return -EINVAL; |
| } |
| } |
| |
| /* |
| * Otherwise it will be difficult to maintain |
| * sk->sk_dst_cache. |
| */ |
| if (sk->sk_state == TCP_ESTABLISHED && |
| ipv6_addr_equal(daddr, &sk->sk_v6_daddr)) |
| daddr = &sk->sk_v6_daddr; |
| |
| if (addr_len >= sizeof(struct sockaddr_in6) && |
| sin6->sin6_scope_id && |
| __ipv6_addr_needs_scope_id(__ipv6_addr_type(daddr))) |
| fl6->flowi6_oif = sin6->sin6_scope_id; |
| } else { |
| if (sk->sk_state != TCP_ESTABLISHED) |
| return -EDESTADDRREQ; |
| |
| fl6->fl6_dport = inet->inet_dport; |
| daddr = &sk->sk_v6_daddr; |
| fl6->flowlabel = np->flow_label; |
| connected = true; |
| } |
| |
| if (!fl6->flowi6_oif) |
| fl6->flowi6_oif = READ_ONCE(sk->sk_bound_dev_if); |
| |
| if (!fl6->flowi6_oif) |
| fl6->flowi6_oif = np->sticky_pktinfo.ipi6_ifindex; |
| |
| fl6->flowi6_uid = sk->sk_uid; |
| |
| if (msg->msg_controllen) { |
| opt = &opt_space; |
| memset(opt, 0, sizeof(struct ipv6_txoptions)); |
| opt->tot_len = sizeof(*opt); |
| ipc6.opt = opt; |
| |
| err = udp_cmsg_send(sk, msg, &ipc6.gso_size); |
| if (err > 0) { |
| err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, fl6, |
| &ipc6); |
| connected = false; |
| } |
| if (err < 0) { |
| fl6_sock_release(flowlabel); |
| return err; |
| } |
| if ((fl6->flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) { |
| flowlabel = fl6_sock_lookup(sk, fl6->flowlabel); |
| if (IS_ERR(flowlabel)) |
| return -EINVAL; |
| } |
| if (!(opt->opt_nflen|opt->opt_flen)) |
| opt = NULL; |
| } |
| if (!opt) { |
| opt = txopt_get(np); |
| opt_to_free = opt; |
| } |
| if (flowlabel) |
| opt = fl6_merge_options(&opt_space, flowlabel, opt); |
| opt = ipv6_fixup_options(&opt_space, opt); |
| ipc6.opt = opt; |
| |
| fl6->flowi6_proto = sk->sk_protocol; |
| fl6->flowi6_mark = ipc6.sockc.mark; |
| fl6->daddr = *daddr; |
| if (ipv6_addr_any(&fl6->saddr) && !ipv6_addr_any(&np->saddr)) |
| fl6->saddr = np->saddr; |
| fl6->fl6_sport = inet->inet_sport; |
| |
| if (cgroup_bpf_enabled(CGROUP_UDP6_SENDMSG) && !connected) { |
| err = BPF_CGROUP_RUN_PROG_UDP6_SENDMSG_LOCK(sk, |
| (struct sockaddr *)sin6, |
| &addr_len, |
| &fl6->saddr); |
| if (err) |
| goto out_no_dst; |
| if (sin6) { |
| if (ipv6_addr_v4mapped(&sin6->sin6_addr)) { |
| /* BPF program rewrote IPv6-only by IPv4-mapped |
| * IPv6. It's currently unsupported. |
| */ |
| err = -ENOTSUPP; |
| goto out_no_dst; |
| } |
| if (sin6->sin6_port == 0) { |
| /* BPF program set invalid port. Reject it. */ |
| err = -EINVAL; |
| goto out_no_dst; |
| } |
| fl6->fl6_dport = sin6->sin6_port; |
| fl6->daddr = sin6->sin6_addr; |
| } |
| } |
| |
| if (ipv6_addr_any(&fl6->daddr)) |
| fl6->daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */ |
| |
| final_p = fl6_update_dst(fl6, opt, &final); |
| if (final_p) |
| connected = false; |
| |
| if (!fl6->flowi6_oif && ipv6_addr_is_multicast(&fl6->daddr)) { |
| fl6->flowi6_oif = READ_ONCE(np->mcast_oif); |
| connected = false; |
| } else if (!fl6->flowi6_oif) |
| fl6->flowi6_oif = READ_ONCE(np->ucast_oif); |
| |
| security_sk_classify_flow(sk, flowi6_to_flowi_common(fl6)); |
| |
| if (ipc6.tclass < 0) |
| ipc6.tclass = np->tclass; |
| |
| fl6->flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6->flowlabel); |
| |
| dst = ip6_sk_dst_lookup_flow(sk, fl6, final_p, connected); |
| if (IS_ERR(dst)) { |
| err = PTR_ERR(dst); |
| dst = NULL; |
| goto out; |
| } |
| |
| if (ipc6.hlimit < 0) |
| ipc6.hlimit = ip6_sk_dst_hoplimit(np, fl6, dst); |
| |
| if (msg->msg_flags&MSG_CONFIRM) |
| goto do_confirm; |
| back_from_confirm: |
| |
| /* Lockless fast path for the non-corking case */ |
| if (!corkreq) { |
| struct sk_buff *skb; |
| |
| skb = ip6_make_skb(sk, getfrag, msg, ulen, |
| sizeof(struct udphdr), &ipc6, |
| dst_rt6_info(dst), |
| msg->msg_flags, &cork); |
| err = PTR_ERR(skb); |
| if (!IS_ERR_OR_NULL(skb)) |
| err = udp_v6_send_skb(skb, fl6, &cork.base); |
| /* ip6_make_skb steals dst reference */ |
| goto out_no_dst; |
| } |
| |
| lock_sock(sk); |
| if (unlikely(up->pending)) { |
| /* The socket is already corked while preparing it. */ |
| /* ... which is an evident application bug. --ANK */ |
| release_sock(sk); |
| |
| net_dbg_ratelimited("udp cork app bug 2\n"); |
| err = -EINVAL; |
| goto out; |
| } |
| |
| WRITE_ONCE(up->pending, AF_INET6); |
| |
| do_append_data: |
| if (ipc6.dontfrag < 0) |
| ipc6.dontfrag = inet6_test_bit(DONTFRAG, sk); |
| up->len += ulen; |
| err = ip6_append_data(sk, getfrag, msg, ulen, sizeof(struct udphdr), |
| &ipc6, fl6, dst_rt6_info(dst), |
| corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags); |
| if (err) |
| udp_v6_flush_pending_frames(sk); |
| else if (!corkreq) |
| err = udp_v6_push_pending_frames(sk); |
| else if (unlikely(skb_queue_empty(&sk->sk_write_queue))) |
| WRITE_ONCE(up->pending, 0); |
| |
| if (err > 0) |
| err = inet6_test_bit(RECVERR6, sk) ? net_xmit_errno(err) : 0; |
| release_sock(sk); |
| |
| out: |
| dst_release(dst); |
| out_no_dst: |
| fl6_sock_release(flowlabel); |
| txopt_put(opt_to_free); |
| if (!err) |
| return len; |
| /* |
| * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting |
| * ENOBUFS might not be good (it's not tunable per se), but otherwise |
| * we don't have a good statistic (IpOutDiscards but it can be too many |
| * things). We could add another new stat but at least for now that |
| * seems like overkill. |
| */ |
| if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) { |
| UDP6_INC_STATS(sock_net(sk), |
| UDP_MIB_SNDBUFERRORS, is_udplite); |
| } |
| return err; |
| |
| do_confirm: |
| if (msg->msg_flags & MSG_PROBE) |
| dst_confirm_neigh(dst, &fl6->daddr); |
| if (!(msg->msg_flags&MSG_PROBE) || len) |
| goto back_from_confirm; |
| err = 0; |
| goto out; |
| } |
| EXPORT_SYMBOL(udpv6_sendmsg); |
| |
| static void udpv6_splice_eof(struct socket *sock) |
| { |
| struct sock *sk = sock->sk; |
| struct udp_sock *up = udp_sk(sk); |
| |
| if (!READ_ONCE(up->pending) || udp_test_bit(CORK, sk)) |
| return; |
| |
| lock_sock(sk); |
| if (up->pending && !udp_test_bit(CORK, sk)) |
| udp_v6_push_pending_frames(sk); |
| release_sock(sk); |
| } |
| |
| void udpv6_destroy_sock(struct sock *sk) |
| { |
| struct udp_sock *up = udp_sk(sk); |
| lock_sock(sk); |
| |
| /* protects from races with udp_abort() */ |
| sock_set_flag(sk, SOCK_DEAD); |
| udp_v6_flush_pending_frames(sk); |
| release_sock(sk); |
| |
| if (static_branch_unlikely(&udpv6_encap_needed_key)) { |
| if (up->encap_type) { |
| void (*encap_destroy)(struct sock *sk); |
| encap_destroy = READ_ONCE(up->encap_destroy); |
| if (encap_destroy) |
| encap_destroy(sk); |
| } |
| if (udp_test_bit(ENCAP_ENABLED, sk)) { |
| static_branch_dec(&udpv6_encap_needed_key); |
| udp_encap_disable(); |
| } |
| } |
| } |
| |
| /* |
| * Socket option code for UDP |
| */ |
| int udpv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval, |
| unsigned int optlen) |
| { |
| if (level == SOL_UDP || level == SOL_UDPLITE || level == SOL_SOCKET) |
| return udp_lib_setsockopt(sk, level, optname, |
| optval, optlen, |
| udp_v6_push_pending_frames); |
| return ipv6_setsockopt(sk, level, optname, optval, optlen); |
| } |
| |
| int udpv6_getsockopt(struct sock *sk, int level, int optname, |
| char __user *optval, int __user *optlen) |
| { |
| if (level == SOL_UDP || level == SOL_UDPLITE) |
| return udp_lib_getsockopt(sk, level, optname, optval, optlen); |
| return ipv6_getsockopt(sk, level, optname, optval, optlen); |
| } |
| |
| |
| /* ------------------------------------------------------------------------ */ |
| #ifdef CONFIG_PROC_FS |
| int udp6_seq_show(struct seq_file *seq, void *v) |
| { |
| if (v == SEQ_START_TOKEN) { |
| seq_puts(seq, IPV6_SEQ_DGRAM_HEADER); |
| } else { |
| int bucket = ((struct udp_iter_state *)seq->private)->bucket; |
| const struct inet_sock *inet = inet_sk((const struct sock *)v); |
| __u16 srcp = ntohs(inet->inet_sport); |
| __u16 destp = ntohs(inet->inet_dport); |
| __ip6_dgram_sock_seq_show(seq, v, srcp, destp, |
| udp_rqueue_get(v), bucket); |
| } |
| return 0; |
| } |
| |
| const struct seq_operations udp6_seq_ops = { |
| .start = udp_seq_start, |
| .next = udp_seq_next, |
| .stop = udp_seq_stop, |
| .show = udp6_seq_show, |
| }; |
| EXPORT_SYMBOL(udp6_seq_ops); |
| |
| static struct udp_seq_afinfo udp6_seq_afinfo = { |
| .family = AF_INET6, |
| .udp_table = NULL, |
| }; |
| |
| int __net_init udp6_proc_init(struct net *net) |
| { |
| if (!proc_create_net_data("udp6", 0444, net->proc_net, &udp6_seq_ops, |
| sizeof(struct udp_iter_state), &udp6_seq_afinfo)) |
| return -ENOMEM; |
| return 0; |
| } |
| |
| void udp6_proc_exit(struct net *net) |
| { |
| remove_proc_entry("udp6", net->proc_net); |
| } |
| #endif /* CONFIG_PROC_FS */ |
| |
| /* ------------------------------------------------------------------------ */ |
| |
| struct proto udpv6_prot = { |
| .name = "UDPv6", |
| .owner = THIS_MODULE, |
| .close = udp_lib_close, |
| .pre_connect = udpv6_pre_connect, |
| .connect = ip6_datagram_connect, |
| .disconnect = udp_disconnect, |
| .ioctl = udp_ioctl, |
| .init = udpv6_init_sock, |
| .destroy = udpv6_destroy_sock, |
| .setsockopt = udpv6_setsockopt, |
| .getsockopt = udpv6_getsockopt, |
| .sendmsg = udpv6_sendmsg, |
| .recvmsg = udpv6_recvmsg, |
| .splice_eof = udpv6_splice_eof, |
| .release_cb = ip6_datagram_release_cb, |
| .hash = udp_lib_hash, |
| .unhash = udp_lib_unhash, |
| .rehash = udp_v6_rehash, |
| .get_port = udp_v6_get_port, |
| .put_port = udp_lib_unhash, |
| #ifdef CONFIG_BPF_SYSCALL |
| .psock_update_sk_prot = udp_bpf_update_proto, |
| #endif |
| |
| .memory_allocated = &udp_memory_allocated, |
| .per_cpu_fw_alloc = &udp_memory_per_cpu_fw_alloc, |
| |
| .sysctl_mem = sysctl_udp_mem, |
| .sysctl_wmem_offset = offsetof(struct net, ipv4.sysctl_udp_wmem_min), |
| .sysctl_rmem_offset = offsetof(struct net, ipv4.sysctl_udp_rmem_min), |
| .obj_size = sizeof(struct udp6_sock), |
| .ipv6_pinfo_offset = offsetof(struct udp6_sock, inet6), |
| .h.udp_table = NULL, |
| .diag_destroy = udp_abort, |
| }; |
| |
| static struct inet_protosw udpv6_protosw = { |
| .type = SOCK_DGRAM, |
| .protocol = IPPROTO_UDP, |
| .prot = &udpv6_prot, |
| .ops = &inet6_dgram_ops, |
| .flags = INET_PROTOSW_PERMANENT, |
| }; |
| |
| int __init udpv6_init(void) |
| { |
| int ret; |
| |
| net_hotdata.udpv6_protocol = (struct inet6_protocol) { |
| .handler = udpv6_rcv, |
| .err_handler = udpv6_err, |
| .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL, |
| }; |
| ret = inet6_add_protocol(&net_hotdata.udpv6_protocol, IPPROTO_UDP); |
| if (ret) |
| goto out; |
| |
| ret = inet6_register_protosw(&udpv6_protosw); |
| if (ret) |
| goto out_udpv6_protocol; |
| out: |
| return ret; |
| |
| out_udpv6_protocol: |
| inet6_del_protocol(&net_hotdata.udpv6_protocol, IPPROTO_UDP); |
| goto out; |
| } |
| |
| void udpv6_exit(void) |
| { |
| inet6_unregister_protosw(&udpv6_protosw); |
| inet6_del_protocol(&net_hotdata.udpv6_protocol, IPPROTO_UDP); |
| } |