// SPDX-License-Identifier: GPL-2.0-or-later /* SCTP kernel implementation * (C) Copyright IBM Corp. 2002, 2004 * Copyright (c) 2001 Nokia, Inc. * Copyright (c) 2001 La Monte H.P. Yarroll * Copyright (c) 2002-2003 Intel Corp. * * This file is part of the SCTP kernel implementation * * SCTP over IPv6. * * Please send any bug reports or fixes you make to the * email address(es): * lksctp developers * * Written or modified by: * Le Yanqun * Hui Huang * La Monte H.P. Yarroll * Sridhar Samudrala * Jon Grimm * Ardelle Fan * * Based on: * linux/net/ipv6/tcp_ipv6.c */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include static inline int sctp_v6_addr_match_len(union sctp_addr *s1, union sctp_addr *s2); static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr, __be16 port); static int sctp_v6_cmp_addr(const union sctp_addr *addr1, const union sctp_addr *addr2); /* Event handler for inet6 address addition/deletion events. * The sctp_local_addr_list needs to be protocted by a spin lock since * multiple notifiers (say IPv4 and IPv6) may be running at the same * time and thus corrupt the list. * The reader side is protected with RCU. */ static int sctp_inet6addr_event(struct notifier_block *this, unsigned long ev, void *ptr) { struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr; struct sctp_sockaddr_entry *addr = NULL; struct sctp_sockaddr_entry *temp; struct net *net = dev_net(ifa->idev->dev); int found = 0; switch (ev) { case NETDEV_UP: addr = kzalloc(sizeof(*addr), GFP_ATOMIC); if (addr) { addr->a.v6.sin6_family = AF_INET6; addr->a.v6.sin6_addr = ifa->addr; addr->a.v6.sin6_scope_id = ifa->idev->dev->ifindex; addr->valid = 1; spin_lock_bh(&net->sctp.local_addr_lock); list_add_tail_rcu(&addr->list, &net->sctp.local_addr_list); sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_NEW); spin_unlock_bh(&net->sctp.local_addr_lock); } break; case NETDEV_DOWN: spin_lock_bh(&net->sctp.local_addr_lock); list_for_each_entry_safe(addr, temp, &net->sctp.local_addr_list, list) { if (addr->a.sa.sa_family == AF_INET6 && ipv6_addr_equal(&addr->a.v6.sin6_addr, &ifa->addr)) { sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_DEL); found = 1; addr->valid = 0; list_del_rcu(&addr->list); break; } } spin_unlock_bh(&net->sctp.local_addr_lock); if (found) kfree_rcu(addr, rcu); break; } return NOTIFY_DONE; } static struct notifier_block sctp_inet6addr_notifier = { .notifier_call = sctp_inet6addr_event, }; static void sctp_v6_err_handle(struct sctp_transport *t, struct sk_buff *skb, __u8 type, __u8 code, __u32 info) { struct sctp_association *asoc = t->asoc; struct sock *sk = asoc->base.sk; struct ipv6_pinfo *np; int err = 0; switch (type) { case ICMPV6_PKT_TOOBIG: if (ip6_sk_accept_pmtu(sk)) sctp_icmp_frag_needed(sk, asoc, t, info); return; case ICMPV6_PARAMPROB: if (ICMPV6_UNK_NEXTHDR == code) { sctp_icmp_proto_unreachable(sk, asoc, t); return; } break; case NDISC_REDIRECT: sctp_icmp_redirect(sk, t, skb); return; default: break; } np = inet6_sk(sk); icmpv6_err_convert(type, code, &err); if (!sock_owned_by_user(sk) && np->recverr) { sk->sk_err = err; sk->sk_error_report(sk); } else { sk->sk_err_soft = err; } } /* ICMP error handler. */ static int sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, u8 type, u8 code, int offset, __be32 info) { struct net *net = dev_net(skb->dev); struct sctp_transport *transport; struct sctp_association *asoc; __u16 saveip, savesctp; struct sock *sk; /* Fix up skb to look at the embedded net header. */ saveip = skb->network_header; savesctp = skb->transport_header; skb_reset_network_header(skb); skb_set_transport_header(skb, offset); sk = sctp_err_lookup(net, AF_INET6, skb, sctp_hdr(skb), &asoc, &transport); /* Put back, the original pointers. */ skb->network_header = saveip; skb->transport_header = savesctp; if (!sk) { __ICMP6_INC_STATS(net, __in6_dev_get(skb->dev), ICMP6_MIB_INERRORS); return -ENOENT; } sctp_v6_err_handle(transport, skb, type, code, ntohl(info)); sctp_err_finish(sk, transport); return 0; } int sctp_udp_v6_err(struct sock *sk, struct sk_buff *skb) { struct net *net = dev_net(skb->dev); struct sctp_association *asoc; struct sctp_transport *t; struct icmp6hdr *hdr; __u32 info = 0; skb->transport_header += sizeof(struct udphdr); sk = sctp_err_lookup(net, AF_INET6, skb, sctp_hdr(skb), &asoc, &t); if (!sk) { __ICMP6_INC_STATS(net, __in6_dev_get(skb->dev), ICMP6_MIB_INERRORS); return -ENOENT; } skb->transport_header -= sizeof(struct udphdr); hdr = (struct icmp6hdr *)(skb_network_header(skb) - sizeof(struct icmp6hdr)); if (hdr->icmp6_type == NDISC_REDIRECT) { /* can't be handled without outer ip6hdr known, leave it to udpv6_err */ sctp_err_finish(sk, t); return 0; } if (hdr->icmp6_type == ICMPV6_PKT_TOOBIG) info = ntohl(hdr->icmp6_mtu); sctp_v6_err_handle(t, skb, hdr->icmp6_type, hdr->icmp6_code, info); sctp_err_finish(sk, t); return 1; } static int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *t) { struct dst_entry *dst = dst_clone(t->dst); struct flowi6 *fl6 = &t->fl.u.ip6; struct sock *sk = skb->sk; struct ipv6_pinfo *np = inet6_sk(sk); __u8 tclass = np->tclass; __be32 label; pr_debug("%s: skb:%p, len:%d, src:%pI6 dst:%pI6\n", __func__, skb, skb->len, &fl6->saddr, &fl6->daddr); if (t->dscp & SCTP_DSCP_SET_MASK) tclass = t->dscp & SCTP_DSCP_VAL_MASK; if (INET_ECN_is_capable(tclass)) IP6_ECN_flow_xmit(sk, fl6->flowlabel); if (!(t->param_flags & SPP_PMTUD_ENABLE)) skb->ignore_df = 1; SCTP_INC_STATS(sock_net(sk), SCTP_MIB_OUTSCTPPACKS); if (!t->encap_port || !sctp_sk(sk)->udp_port) { int res; skb_dst_set(skb, dst); rcu_read_lock(); res = ip6_xmit(sk, skb, fl6, sk->sk_mark, rcu_dereference(np->opt), tclass, sk->sk_priority); rcu_read_unlock(); return res; } if (skb_is_gso(skb)) skb_shinfo(skb)->gso_type |= SKB_GSO_UDP_TUNNEL_CSUM; skb->encapsulation = 1; skb_reset_inner_mac_header(skb); skb_reset_inner_transport_header(skb); skb_set_inner_ipproto(skb, IPPROTO_SCTP); label = ip6_make_flowlabel(sock_net(sk), skb, fl6->flowlabel, true, fl6); return udp_tunnel6_xmit_skb(dst, sk, skb, NULL, &fl6->saddr, &fl6->daddr, tclass, ip6_dst_hoplimit(dst), label, sctp_sk(sk)->udp_port, t->encap_port, false); } /* Returns the dst cache entry for the given source and destination ip * addresses. */ static void sctp_v6_get_dst(struct sctp_transport *t, union sctp_addr *saddr, struct flowi *fl, struct sock *sk) { struct sctp_association *asoc = t->asoc; struct dst_entry *dst = NULL; struct flowi _fl; struct flowi6 *fl6 = &_fl.u.ip6; struct sctp_bind_addr *bp; struct ipv6_pinfo *np = inet6_sk(sk); struct sctp_sockaddr_entry *laddr; union sctp_addr *daddr = &t->ipaddr; union sctp_addr dst_saddr; struct in6_addr *final_p, final; enum sctp_scope scope; __u8 matchlen = 0; memset(&_fl, 0, sizeof(_fl)); fl6->daddr = daddr->v6.sin6_addr; fl6->fl6_dport = daddr->v6.sin6_port; fl6->flowi6_proto = IPPROTO_SCTP; if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) fl6->flowi6_oif = daddr->v6.sin6_scope_id; else if (asoc) fl6->flowi6_oif = asoc->base.sk->sk_bound_dev_if; if (t->flowlabel & SCTP_FLOWLABEL_SET_MASK) fl6->flowlabel = htonl(t->flowlabel & SCTP_FLOWLABEL_VAL_MASK); if (np->sndflow && (fl6->flowlabel & IPV6_FLOWLABEL_MASK)) { struct ip6_flowlabel *flowlabel; flowlabel = fl6_sock_lookup(sk, fl6->flowlabel); if (IS_ERR(flowlabel)) goto out; fl6_sock_release(flowlabel); } pr_debug("%s: dst=%pI6 ", __func__, &fl6->daddr); if (asoc) fl6->fl6_sport = htons(asoc->base.bind_addr.port); if (saddr) { fl6->saddr = saddr->v6.sin6_addr; if (!fl6->fl6_sport) fl6->fl6_sport = saddr->v6.sin6_port; pr_debug("src=%pI6 - ", &fl6->saddr); } rcu_read_lock(); final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final); rcu_read_unlock(); dst = ip6_dst_lookup_flow(sock_net(sk), sk, fl6, final_p); if (!asoc || saddr) { t->dst = dst; memcpy(fl, &_fl, sizeof(_fl)); goto out; } bp = &asoc->base.bind_addr; scope = sctp_scope(daddr); /* ip6_dst_lookup has filled in the fl6->saddr for us. Check * to see if we can use it. */ if (!IS_ERR(dst)) { /* Walk through the bind address list and look for a bind * address that matches the source address of the returned dst. */ sctp_v6_to_addr(&dst_saddr, &fl6->saddr, htons(bp->port)); rcu_read_lock(); list_for_each_entry_rcu(laddr, &bp->address_list, list) { if (!laddr->valid || laddr->state == SCTP_ADDR_DEL || (laddr->state != SCTP_ADDR_SRC && !asoc->src_out_of_asoc_ok)) continue; /* Do not compare against v4 addrs */ if ((laddr->a.sa.sa_family == AF_INET6) && (sctp_v6_cmp_addr(&dst_saddr, &laddr->a))) { rcu_read_unlock(); t->dst = dst; memcpy(fl, &_fl, sizeof(_fl)); goto out; } } rcu_read_unlock(); /* None of the bound addresses match the source address of the * dst. So release it. */ dst_release(dst); dst = NULL; } /* Walk through the bind address list and try to get the * best source address for a given destination. */ rcu_read_lock(); list_for_each_entry_rcu(laddr, &bp->address_list, list) { struct dst_entry *bdst; __u8 bmatchlen; if (!laddr->valid || laddr->state != SCTP_ADDR_SRC || laddr->a.sa.sa_family != AF_INET6 || scope > sctp_scope(&laddr->a)) continue; fl6->saddr = laddr->a.v6.sin6_addr; fl6->fl6_sport = laddr->a.v6.sin6_port; final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final); bdst = ip6_dst_lookup_flow(sock_net(sk), sk, fl6, final_p); if (IS_ERR(bdst)) continue; if (ipv6_chk_addr(dev_net(bdst->dev), &laddr->a.v6.sin6_addr, bdst->dev, 1)) { if (!IS_ERR_OR_NULL(dst)) dst_release(dst); dst = bdst; t->dst = dst; memcpy(fl, &_fl, sizeof(_fl)); break; } bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a); if (matchlen > bmatchlen) { dst_release(bdst); continue; } if (!IS_ERR_OR_NULL(dst)) dst_release(dst); dst = bdst; matchlen = bmatchlen; t->dst = dst; memcpy(fl, &_fl, sizeof(_fl)); } rcu_read_unlock(); out: if (!IS_ERR_OR_NULL(dst)) { struct rt6_info *rt; rt = (struct rt6_info *)dst; t->dst_cookie = rt6_get_cookie(rt); pr_debug("rt6_dst:%pI6/%d rt6_src:%pI6\n", &rt->rt6i_dst.addr, rt->rt6i_dst.plen, &fl->u.ip6.saddr); } else { t->dst = NULL; pr_debug("no route\n"); } } /* Returns the number of consecutive initial bits that match in the 2 ipv6 * addresses. */ static inline int sctp_v6_addr_match_len(union sctp_addr *s1, union sctp_addr *s2) { return ipv6_addr_diff(&s1->v6.sin6_addr, &s2->v6.sin6_addr); } /* Fills in the source address(saddr) based on the destination address(daddr) * and asoc's bind address list. */ static void sctp_v6_get_saddr(struct sctp_sock *sk, struct sctp_transport *t, struct flowi *fl) { struct flowi6 *fl6 = &fl->u.ip6; union sctp_addr *saddr = &t->saddr; pr_debug("%s: asoc:%p dst:%p\n", __func__, t->asoc, t->dst); if (t->dst) { saddr->v6.sin6_family = AF_INET6; saddr->v6.sin6_addr = fl6->saddr; } } /* Make a copy of all potential local addresses. */ static void sctp_v6_copy_addrlist(struct list_head *addrlist, struct net_device *dev) { struct inet6_dev *in6_dev; struct inet6_ifaddr *ifp; struct sctp_sockaddr_entry *addr; rcu_read_lock(); if ((in6_dev = __in6_dev_get(dev)) == NULL) { rcu_read_unlock(); return; } read_lock_bh(&in6_dev->lock); list_for_each_entry(ifp, &in6_dev->addr_list, if_list) { /* Add the address to the local list. */ addr = kzalloc(sizeof(*addr), GFP_ATOMIC); if (addr) { addr->a.v6.sin6_family = AF_INET6; addr->a.v6.sin6_addr = ifp->addr; addr->a.v6.sin6_scope_id = dev->ifindex; addr->valid = 1; INIT_LIST_HEAD(&addr->list); list_add_tail(&addr->list, addrlist); } } read_unlock_bh(&in6_dev->lock); rcu_read_unlock(); } /* Copy over any ip options */ static void sctp_v6_copy_ip_options(struct sock *sk, struct sock *newsk) { struct ipv6_pinfo *newnp, *np = inet6_sk(sk); struct ipv6_txoptions *opt; newnp = inet6_sk(newsk); rcu_read_lock(); opt = rcu_dereference(np->opt); if (opt) { opt = ipv6_dup_options(newsk, opt); if (!opt) pr_err("%s: Failed to copy ip options\n", __func__); } RCU_INIT_POINTER(newnp->opt, opt); rcu_read_unlock(); } /* Account for the IP options */ static int sctp_v6_ip_options_len(struct sock *sk) { struct ipv6_pinfo *np = inet6_sk(sk); struct ipv6_txoptions *opt; int len = 0; rcu_read_lock(); opt = rcu_dereference(np->opt); if (opt) len = opt->opt_flen + opt->opt_nflen; rcu_read_unlock(); return len; } /* Initialize a sockaddr_storage from in incoming skb. */ static void sctp_v6_from_skb(union sctp_addr *addr, struct sk_buff *skb, int is_saddr) { /* Always called on head skb, so this is safe */ struct sctphdr *sh = sctp_hdr(skb); struct sockaddr_in6 *sa = &addr->v6; addr->v6.sin6_family = AF_INET6; addr->v6.sin6_flowinfo = 0; /* FIXME */ addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif; if (is_saddr) { sa->sin6_port = sh->source; sa->sin6_addr = ipv6_hdr(skb)->saddr; } else { sa->sin6_port = sh->dest; sa->sin6_addr = ipv6_hdr(skb)->daddr; } } /* Initialize an sctp_addr from a socket. */ static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk) { addr->v6.sin6_family = AF_INET6; addr->v6.sin6_port = 0; addr->v6.sin6_addr = sk->sk_v6_rcv_saddr; } /* Initialize sk->sk_rcv_saddr from sctp_addr. */ static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk) { if (addr->sa.sa_family == AF_INET) { sk->sk_v6_rcv_saddr.s6_addr32[0] = 0; sk->sk_v6_rcv_saddr.s6_addr32[1] = 0; sk->sk_v6_rcv_saddr.s6_addr32[2] = htonl(0x0000ffff); sk->sk_v6_rcv_saddr.s6_addr32[3] = addr->v4.sin_addr.s_addr; } else { sk->sk_v6_rcv_saddr = addr->v6.sin6_addr; } } /* Initialize sk->sk_daddr from sctp_addr. */ static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk) { if (addr->sa.sa_family == AF_INET) { sk->sk_v6_daddr.s6_addr32[0] = 0; sk->sk_v6_daddr.s6_addr32[1] = 0; sk->sk_v6_daddr.s6_addr32[2] = htonl(0x0000ffff); sk->sk_v6_daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr; } else { sk->sk_v6_daddr = addr->v6.sin6_addr; } } /* Initialize a sctp_addr from an address parameter. */ static void sctp_v6_from_addr_param(union sctp_addr *addr, union sctp_addr_param *param, __be16 port, int iif) { addr->v6.sin6_family = AF_INET6; addr->v6.sin6_port = port; addr->v6.sin6_flowinfo = 0; /* BUG */ addr->v6.sin6_addr = param->v6.addr; addr->v6.sin6_scope_id = iif; } /* Initialize an address parameter from a sctp_addr and return the length * of the address parameter. */ static int sctp_v6_to_addr_param(const union sctp_addr *addr, union sctp_addr_param *param) { int length = sizeof(struct sctp_ipv6addr_param); param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS; param->v6.param_hdr.length = htons(length); param->v6.addr = addr->v6.sin6_addr; return length; } /* Initialize a sctp_addr from struct in6_addr. */ static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr, __be16 port) { addr->sa.sa_family = AF_INET6; addr->v6.sin6_port = port; addr->v6.sin6_flowinfo = 0; addr->v6.sin6_addr = *saddr; addr->v6.sin6_scope_id = 0; } static int __sctp_v6_cmp_addr(const union sctp_addr *addr1, const union sctp_addr *addr2) { if (addr1->sa.sa_family != addr2->sa.sa_family) { if (addr1->sa.sa_family == AF_INET && addr2->sa.sa_family == AF_INET6 && ipv6_addr_v4mapped(&addr2->v6.sin6_addr) && addr2->v6.sin6_addr.s6_addr32[3] == addr1->v4.sin_addr.s_addr) return 1; if (addr2->sa.sa_family == AF_INET && addr1->sa.sa_family == AF_INET6 && ipv6_addr_v4mapped(&addr1->v6.sin6_addr) && addr1->v6.sin6_addr.s6_addr32[3] == addr2->v4.sin_addr.s_addr) return 1; return 0; } if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr)) return 0; /* If this is a linklocal address, compare the scope_id. */ if ((ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) && addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id && addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id) return 0; return 1; } /* Compare addresses exactly. * v4-mapped-v6 is also in consideration. */ static int sctp_v6_cmp_addr(const union sctp_addr *addr1, const union sctp_addr *addr2) { return __sctp_v6_cmp_addr(addr1, addr2) && addr1->v6.sin6_port == addr2->v6.sin6_port; } /* Initialize addr struct to INADDR_ANY. */ static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port) { memset(addr, 0x00, sizeof(union sctp_addr)); addr->v6.sin6_family = AF_INET6; addr->v6.sin6_port = port; } /* Is this a wildcard address? */ static int sctp_v6_is_any(const union sctp_addr *addr) { return ipv6_addr_any(&addr->v6.sin6_addr); } /* Should this be available for binding? */ static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp) { int type; struct net *net = sock_net(&sp->inet.sk); const struct in6_addr *in6 = (const struct in6_addr *)&addr->v6.sin6_addr; type = ipv6_addr_type(in6); if (IPV6_ADDR_ANY == type) return 1; if (type == IPV6_ADDR_MAPPED) { if (sp && ipv6_only_sock(sctp_opt2sk(sp))) return 0; sctp_v6_map_v4(addr); return sctp_get_af_specific(AF_INET)->available(addr, sp); } if (!(type & IPV6_ADDR_UNICAST)) return 0; return ipv6_can_nonlocal_bind(net, &sp->inet) || ipv6_chk_addr(net, in6, NULL, 0); } /* This function checks if the address is a valid address to be used for * SCTP. * * Output: * Return 0 - If the address is a non-unicast or an illegal address. * Return 1 - If the address is a unicast. */ static int sctp_v6_addr_valid(union sctp_addr *addr, struct sctp_sock *sp, const struct sk_buff *skb) { int ret = ipv6_addr_type(&addr->v6.sin6_addr); /* Support v4-mapped-v6 address. */ if (ret == IPV6_ADDR_MAPPED) { /* Note: This routine is used in input, so v4-mapped-v6 * are disallowed here when there is no sctp_sock. */ if (sp && ipv6_only_sock(sctp_opt2sk(sp))) return 0; sctp_v6_map_v4(addr); return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb); } /* Is this a non-unicast address */ if (!(ret & IPV6_ADDR_UNICAST)) return 0; return 1; } /* What is the scope of 'addr'? */ static enum sctp_scope sctp_v6_scope(union sctp_addr *addr) { enum sctp_scope retval; int v6scope; /* The IPv6 scope is really a set of bit fields. * See IFA_* in . Map to a generic SCTP scope. */ v6scope = ipv6_addr_scope(&addr->v6.sin6_addr); switch (v6scope) { case IFA_HOST: retval = SCTP_SCOPE_LOOPBACK; break; case IFA_LINK: retval = SCTP_SCOPE_LINK; break; case IFA_SITE: retval = SCTP_SCOPE_PRIVATE; break; default: retval = SCTP_SCOPE_GLOBAL; break; } return retval; } /* Create and initialize a new sk for the socket to be returned by accept(). */ static struct sock *sctp_v6_create_accept_sk(struct sock *sk, struct sctp_association *asoc, bool kern) { struct sock *newsk; struct ipv6_pinfo *newnp, *np = inet6_sk(sk); struct sctp6_sock *newsctp6sk; newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot, kern); if (!newsk) goto out; sock_init_data(NULL, newsk); sctp_copy_sock(newsk, sk, asoc); sock_reset_flag(sk, SOCK_ZAPPED); newsctp6sk = (struct sctp6_sock *)newsk; inet_sk(newsk)->pinet6 = &newsctp6sk->inet6; sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped; newnp = inet6_sk(newsk); memcpy(newnp, np, sizeof(struct ipv6_pinfo)); newnp->ipv6_mc_list = NULL; newnp->ipv6_ac_list = NULL; newnp->ipv6_fl_list = NULL; sctp_v6_copy_ip_options(sk, newsk); /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname() * and getpeername(). */ sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk); newsk->sk_v6_rcv_saddr = sk->sk_v6_rcv_saddr; sk_refcnt_debug_inc(newsk); if (newsk->sk_prot->init(newsk)) { sk_common_release(newsk); newsk = NULL; } out: return newsk; } /* Format a sockaddr for return to user space. This makes sure the return is * AF_INET or AF_INET6 depending on the SCTP_I_WANT_MAPPED_V4_ADDR option. */ static int sctp_v6_addr_to_user(struct sctp_sock *sp, union sctp_addr *addr) { if (sp->v4mapped) { if (addr->sa.sa_family == AF_INET) sctp_v4_map_v6(addr); } else { if (addr->sa.sa_family == AF_INET6 && ipv6_addr_v4mapped(&addr->v6.sin6_addr)) sctp_v6_map_v4(addr); } if (addr->sa.sa_family == AF_INET) { memset(addr->v4.sin_zero, 0, sizeof(addr->v4.sin_zero)); return sizeof(struct sockaddr_in); } return sizeof(struct sockaddr_in6); } /* Where did this skb come from? */ static int sctp_v6_skb_iif(const struct sk_buff *skb) { return IP6CB(skb)->iif; } /* Was this packet marked by Explicit Congestion Notification? */ static int sctp_v6_is_ce(const struct sk_buff *skb) { return *((__u32 *)(ipv6_hdr(skb))) & (__force __u32)htonl(1 << 20); } /* Dump the v6 addr to the seq file. */ static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr) { seq_printf(seq, "%pI6 ", &addr->v6.sin6_addr); } static void sctp_v6_ecn_capable(struct sock *sk) { inet6_sk(sk)->tclass |= INET_ECN_ECT_0; } /* Initialize a PF_INET msgname from a ulpevent. */ static void sctp_inet6_event_msgname(struct sctp_ulpevent *event, char *msgname, int *addrlen) { union sctp_addr *addr; struct sctp_association *asoc; union sctp_addr *paddr; if (!msgname) return; addr = (union sctp_addr *)msgname; asoc = event->asoc; paddr = &asoc->peer.primary_addr; if (paddr->sa.sa_family == AF_INET) { addr->v4.sin_family = AF_INET; addr->v4.sin_port = htons(asoc->peer.port); addr->v4.sin_addr = paddr->v4.sin_addr; } else { addr->v6.sin6_family = AF_INET6; addr->v6.sin6_flowinfo = 0; if (ipv6_addr_type(&paddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) addr->v6.sin6_scope_id = paddr->v6.sin6_scope_id; else addr->v6.sin6_scope_id = 0; addr->v6.sin6_port = htons(asoc->peer.port); addr->v6.sin6_addr = paddr->v6.sin6_addr; } *addrlen = sctp_v6_addr_to_user(sctp_sk(asoc->base.sk), addr); } /* Initialize a msg_name from an inbound skb. */ static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname, int *addr_len) { union sctp_addr *addr; struct sctphdr *sh; if (!msgname) return; addr = (union sctp_addr *)msgname; sh = sctp_hdr(skb); if (ip_hdr(skb)->version == 4) { addr->v4.sin_family = AF_INET; addr->v4.sin_port = sh->source; addr->v4.sin_addr.s_addr = ip_hdr(skb)->saddr; } else { addr->v6.sin6_family = AF_INET6; addr->v6.sin6_flowinfo = 0; addr->v6.sin6_port = sh->source; addr->v6.sin6_addr = ipv6_hdr(skb)->saddr; if (ipv6_addr_type(&addr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) addr->v6.sin6_scope_id = sctp_v6_skb_iif(skb); else addr->v6.sin6_scope_id = 0; } *addr_len = sctp_v6_addr_to_user(sctp_sk(skb->sk), addr); } /* Do we support this AF? */ static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp) { switch (family) { case AF_INET6: return 1; /* v4-mapped-v6 addresses */ case AF_INET: if (!__ipv6_only_sock(sctp_opt2sk(sp))) return 1; fallthrough; default: return 0; } } /* Address matching with wildcards allowed. This extra level * of indirection lets us choose whether a PF_INET6 should * disallow any v4 addresses if we so choose. */ static int sctp_inet6_cmp_addr(const union sctp_addr *addr1, const union sctp_addr *addr2, struct sctp_sock *opt) { struct sock *sk = sctp_opt2sk(opt); struct sctp_af *af1, *af2; af1 = sctp_get_af_specific(addr1->sa.sa_family); af2 = sctp_get_af_specific(addr2->sa.sa_family); if (!af1 || !af2) return 0; /* If the socket is IPv6 only, v4 addrs will not match */ if (__ipv6_only_sock(sk) && af1 != af2) return 0; /* Today, wildcard AF_INET/AF_INET6. */ if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2)) return 1; if (addr1->sa.sa_family == AF_INET && addr2->sa.sa_family == AF_INET) return addr1->v4.sin_addr.s_addr == addr2->v4.sin_addr.s_addr; return __sctp_v6_cmp_addr(addr1, addr2); } /* Verify that the provided sockaddr looks bindable. Common verification, * has already been taken care of. */ static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr) { struct sctp_af *af; /* ASSERT: address family has already been verified. */ if (addr->sa.sa_family != AF_INET6) af = sctp_get_af_specific(addr->sa.sa_family); else { int type = ipv6_addr_type(&addr->v6.sin6_addr); struct net_device *dev; if (type & IPV6_ADDR_LINKLOCAL) { struct net *net; if (!addr->v6.sin6_scope_id) return 0; net = sock_net(&opt->inet.sk); rcu_read_lock(); dev = dev_get_by_index_rcu(net, addr->v6.sin6_scope_id); if (!dev || !(ipv6_can_nonlocal_bind(net, &opt->inet) || ipv6_chk_addr(net, &addr->v6.sin6_addr, dev, 0))) { rcu_read_unlock(); return 0; } rcu_read_unlock(); } af = opt->pf->af; } return af->available(addr, opt); } /* Verify that the provided sockaddr looks sendable. Common verification, * has already been taken care of. */ static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr) { struct sctp_af *af = NULL; /* ASSERT: address family has already been verified. */ if (addr->sa.sa_family != AF_INET6) af = sctp_get_af_specific(addr->sa.sa_family); else { int type = ipv6_addr_type(&addr->v6.sin6_addr); struct net_device *dev; if (type & IPV6_ADDR_LINKLOCAL) { if (!addr->v6.sin6_scope_id) return 0; rcu_read_lock(); dev = dev_get_by_index_rcu(sock_net(&opt->inet.sk), addr->v6.sin6_scope_id); rcu_read_unlock(); if (!dev) return 0; } af = opt->pf->af; } return af != NULL; } /* Fill in Supported Address Type information for INIT and INIT-ACK * chunks. Note: In the future, we may want to look at sock options * to determine whether a PF_INET6 socket really wants to have IPV4 * addresses. * Returns number of addresses supported. */ static int sctp_inet6_supported_addrs(const struct sctp_sock *opt, __be16 *types) { types[0] = SCTP_PARAM_IPV6_ADDRESS; if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) { types[1] = SCTP_PARAM_IPV4_ADDRESS; return 2; } return 1; } /* Handle SCTP_I_WANT_MAPPED_V4_ADDR for getpeername() and getsockname() */ static int sctp_getname(struct socket *sock, struct sockaddr *uaddr, int peer) { int rc; rc = inet6_getname(sock, uaddr, peer); if (rc < 0) return rc; rc = sctp_v6_addr_to_user(sctp_sk(sock->sk), (union sctp_addr *)uaddr); return rc; } static const struct proto_ops inet6_seqpacket_ops = { .family = PF_INET6, .owner = THIS_MODULE, .release = inet6_release, .bind = inet6_bind, .connect = sctp_inet_connect, .socketpair = sock_no_socketpair, .accept = inet_accept, .getname = sctp_getname, .poll = sctp_poll, .ioctl = inet6_ioctl, .gettstamp = sock_gettstamp, .listen = sctp_inet_listen, .shutdown = inet_shutdown, .setsockopt = sock_common_setsockopt, .getsockopt = sock_common_getsockopt, .sendmsg = inet_sendmsg, .recvmsg = inet_recvmsg, .mmap = sock_no_mmap, #ifdef CONFIG_COMPAT .compat_ioctl = inet6_compat_ioctl, #endif }; static struct inet_protosw sctpv6_seqpacket_protosw = { .type = SOCK_SEQPACKET, .protocol = IPPROTO_SCTP, .prot = &sctpv6_prot, .ops = &inet6_seqpacket_ops, .flags = SCTP_PROTOSW_FLAG }; static struct inet_protosw sctpv6_stream_protosw = { .type = SOCK_STREAM, .protocol = IPPROTO_SCTP, .prot = &sctpv6_prot, .ops = &inet6_seqpacket_ops, .flags = SCTP_PROTOSW_FLAG, }; static int sctp6_rcv(struct sk_buff *skb) { SCTP_INPUT_CB(skb)->encap_port = 0; return sctp_rcv(skb) ? -1 : 0; } static const struct inet6_protocol sctpv6_protocol = { .handler = sctp6_rcv, .err_handler = sctp_v6_err, .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL, }; static struct sctp_af sctp_af_inet6 = { .sa_family = AF_INET6, .sctp_xmit = sctp_v6_xmit, .setsockopt = ipv6_setsockopt, .getsockopt = ipv6_getsockopt, .get_dst = sctp_v6_get_dst, .get_saddr = sctp_v6_get_saddr, .copy_addrlist = sctp_v6_copy_addrlist, .from_skb = sctp_v6_from_skb, .from_sk = sctp_v6_from_sk, .from_addr_param = sctp_v6_from_addr_param, .to_addr_param = sctp_v6_to_addr_param, .cmp_addr = sctp_v6_cmp_addr, .scope = sctp_v6_scope, .addr_valid = sctp_v6_addr_valid, .inaddr_any = sctp_v6_inaddr_any, .is_any = sctp_v6_is_any, .available = sctp_v6_available, .skb_iif = sctp_v6_skb_iif, .is_ce = sctp_v6_is_ce, .seq_dump_addr = sctp_v6_seq_dump_addr, .ecn_capable = sctp_v6_ecn_capable, .net_header_len = sizeof(struct ipv6hdr), .sockaddr_len = sizeof(struct sockaddr_in6), .ip_options_len = sctp_v6_ip_options_len, }; static struct sctp_pf sctp_pf_inet6 = { .event_msgname = sctp_inet6_event_msgname, .skb_msgname = sctp_inet6_skb_msgname, .af_supported = sctp_inet6_af_supported, .cmp_addr = sctp_inet6_cmp_addr, .bind_verify = sctp_inet6_bind_verify, .send_verify = sctp_inet6_send_verify, .supported_addrs = sctp_inet6_supported_addrs, .create_accept_sk = sctp_v6_create_accept_sk, .addr_to_user = sctp_v6_addr_to_user, .to_sk_saddr = sctp_v6_to_sk_saddr, .to_sk_daddr = sctp_v6_to_sk_daddr, .copy_ip_options = sctp_v6_copy_ip_options, .af = &sctp_af_inet6, }; /* Initialize IPv6 support and register with socket layer. */ void sctp_v6_pf_init(void) { /* Register the SCTP specific PF_INET6 functions. */ sctp_register_pf(&sctp_pf_inet6, PF_INET6); /* Register the SCTP specific AF_INET6 functions. */ sctp_register_af(&sctp_af_inet6); } void sctp_v6_pf_exit(void) { list_del(&sctp_af_inet6.list); } /* Initialize IPv6 support and register with socket layer. */ int sctp_v6_protosw_init(void) { int rc; rc = proto_register(&sctpv6_prot, 1); if (rc) return rc; /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */ inet6_register_protosw(&sctpv6_seqpacket_protosw); inet6_register_protosw(&sctpv6_stream_protosw); return 0; } void sctp_v6_protosw_exit(void) { inet6_unregister_protosw(&sctpv6_seqpacket_protosw); inet6_unregister_protosw(&sctpv6_stream_protosw); proto_unregister(&sctpv6_prot); } /* Register with inet6 layer. */ int sctp_v6_add_protocol(void) { /* Register notifier for inet6 address additions/deletions. */ register_inet6addr_notifier(&sctp_inet6addr_notifier); if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0) return -EAGAIN; return 0; } /* Unregister with inet6 layer. */ void sctp_v6_del_protocol(void) { inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP); unregister_inet6addr_notifier(&sctp_inet6addr_notifier); }