/* SCTP kernel reference Implementation * Copyright (c) 2001 Nokia, Inc. * Copyright (c) 2001 La Monte H.P. Yarroll * Copyright (c) 2002 International Business Machines, Corp. * * This file is part of the SCTP kernel reference Implementation * * SCTP over IPv6. * * The SCTP reference implementation is free software; * you can redistribute it and/or modify it under the terms of * the GNU General Public License as published by * the Free Software Foundation; either version 2, or (at your option) * any later version. * * The SCTP reference implementation is distributed in the hope that it * will be useful, but WITHOUT ANY WARRANTY; without even the implied * ************************ * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. * See the GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with GNU CC; see the file COPYING. If not, write to * the Free Software Foundation, 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. * * Please send any bug reports or fixes you make to the * email address(es): * lksctp developers <lksctp-developers@lists.sourceforge.net> * * Or submit a bug report through the following website: * http://www.sf.net/projects/lksctp * * Written or modified by: * Le Yanqun <yanqun.le@nokia.com> * Hui Huang <hui.huang@nokia.com> * La Monte H.P. Yarroll <piggy@acm.org> * Sridhar Samudrala <sri@us.ibm.com> * Jon Grimm <jgrimm@us.ibm.com> * * Based on: * linux/net/ipv6/tcp_ipv6.c * * Any bugs reported given to us we will try to fix... any fixes shared will * be incorporated into the next SCTP release. */ #include <linux/module.h> #include <linux/errno.h> #include <linux/types.h> #include <linux/socket.h> #include <linux/sockios.h> #include <linux/net.h> #include <linux/sched.h> #include <linux/in.h> #include <linux/in6.h> #include <linux/netdevice.h> #include <linux/init.h> #include <linux/ipsec.h> #include <linux/ipv6.h> #include <linux/icmpv6.h> #include <linux/random.h> #include <net/protocol.h> #include <net/tcp.h> #include <net/ndisc.h> #include <net/ipv6.h> #include <net/transp_v6.h> #include <net/addrconf.h> #include <net/ip6_route.h> #include <net/inet_common.h> #include <net/inet_ecn.h> #include <net/sctp/sctp.h> #include <asm/uaccess.h> extern struct notifier_block sctp_inetaddr_notifier; /* FIXME: This macro needs to be moved to a common header file. */ #define NIP6(addr) \ ntohs((addr)->s6_addr16[0]), \ ntohs((addr)->s6_addr16[1]), \ ntohs((addr)->s6_addr16[2]), \ ntohs((addr)->s6_addr16[3]), \ ntohs((addr)->s6_addr16[4]), \ ntohs((addr)->s6_addr16[5]), \ ntohs((addr)->s6_addr16[6]), \ ntohs((addr)->s6_addr16[7]) /* FIXME: Comments. */ static inline void sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, int type, int code, int offset, __u32 info) { /* BUG. WRITE ME. */ } /* Based on tcp_v6_xmit() in tcp_ipv6.c. */ static inline int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *transport, int ipfragok) { struct sock *sk = skb->sk; struct ipv6_pinfo *np = inet6_sk(sk); struct flowi fl; struct dst_entry *dst = skb->dst; struct rt6_info *rt6 = (struct rt6_info *)dst; fl.proto = sk->protocol; /* Fill in the dest address from the route entry passed with the skb * and the source address from the transport. */ fl.fl6_dst = &rt6->rt6i_dst.addr; fl.fl6_src = &transport->saddr.v6.sin6_addr; fl.fl6_flowlabel = np->flow_label; IP6_ECN_flow_xmit(sk, fl.fl6_flowlabel); fl.oif = sk->bound_dev_if; fl.uli_u.ports.sport = inet_sk(sk)->sport; fl.uli_u.ports.dport = inet_sk(sk)->dport; if (np->opt && np->opt->srcrt) { struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt; fl.nl_u.ip6_u.daddr = rt0->addr; } SCTP_DEBUG_PRINTK("%s: skb:%p, len:%d, " "src:%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x " "dst:%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n", __FUNCTION__, skb, skb->len, NIP6(fl.fl6_src), NIP6(fl.fl6_dst)); SCTP_INC_STATS(SctpOutSCTPPacks); return ip6_xmit(sk, skb, &fl, np->opt); } /* Returns the dst cache entry for the given source and destination ip * addresses. */ struct dst_entry *sctp_v6_get_dst(sctp_association_t *asoc, union sctp_addr *daddr, union sctp_addr *saddr) { struct dst_entry *dst; struct flowi fl = { .nl_u = { .ip6_u = { .daddr = &daddr->v6.sin6_addr, } } }; SCTP_DEBUG_PRINTK("%s: DST=%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x ", __FUNCTION__, NIP6(fl.fl6_dst)); if (saddr) { fl.fl6_src = &saddr->v6.sin6_addr; SCTP_DEBUG_PRINTK( "SRC=%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x - ", NIP6(fl.fl6_src)); } dst = ip6_route_output(NULL, &fl); if (dst) { struct rt6_info *rt; rt = (struct rt6_info *)dst; SCTP_DEBUG_PRINTK( "rt6_dst:%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x " "rt6_src:%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n", NIP6(&rt->rt6i_dst.addr), NIP6(&rt->rt6i_src.addr)); } else { SCTP_DEBUG_PRINTK("NO ROUTE\n"); } return dst; } /* 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) { struct in6_addr *a1 = &s1->v6.sin6_addr; struct in6_addr *a2 = &s2->v6.sin6_addr; int i, j; for (i = 0; i < 4 ; i++) { __u32 a1xora2; a1xora2 = a1->s6_addr32[i] ^ a2->s6_addr32[i]; if ((j = fls(ntohl(a1xora2)))) return (i * 32 + 32 - j); } return (i*32); } /* Fills in the source address(saddr) based on the destination address(daddr) * and asoc's bind address list. */ void sctp_v6_get_saddr(sctp_association_t *asoc, struct dst_entry *dst, union sctp_addr *daddr, union sctp_addr *saddr) { sctp_bind_addr_t *bp; rwlock_t *addr_lock; struct sockaddr_storage_list *laddr; struct list_head *pos; sctp_scope_t scope; union sctp_addr *baddr = NULL; __u8 matchlen = 0; __u8 bmatchlen; SCTP_DEBUG_PRINTK("%s: asoc:%p dst:%p " "daddr:%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x ", __FUNCTION__, asoc, dst, NIP6(&daddr->v6.sin6_addr)); if (!asoc) { ipv6_get_saddr(dst, &daddr->v6.sin6_addr, &saddr->v6.sin6_addr); SCTP_DEBUG_PRINTK("saddr from ipv6_get_saddr: " "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n", NIP6(&saddr->v6.sin6_addr)); return; } scope = sctp_scope(daddr); bp = &asoc->base.bind_addr; addr_lock = &asoc->base.addr_lock; /* Go through the bind address list and find the best source address * that matches the scope of the destination address. */ sctp_read_lock(addr_lock); list_for_each(pos, &bp->address_list) { laddr = list_entry(pos, struct sockaddr_storage_list, list); if ((laddr->a.sa.sa_family == AF_INET6) && (scope <= sctp_scope(&laddr->a))) { bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a); if (!baddr || (matchlen < bmatchlen)) { baddr = &laddr->a; matchlen = bmatchlen; } } } if (baddr) { memcpy(saddr, baddr, sizeof(union sctp_addr)); SCTP_DEBUG_PRINTK("saddr: " "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n", NIP6(&saddr->v6.sin6_addr)); } else { printk(KERN_ERR "%s: asoc:%p Could not find a valid source " "address for the " "dest:%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n", __FUNCTION__, asoc, NIP6(&daddr->v6.sin6_addr)); } sctp_read_unlock(addr_lock); } /* 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 sockaddr_storage_list *addr; read_lock(&addrconf_lock); if ((in6_dev = __in6_dev_get(dev)) == NULL) { read_unlock(&addrconf_lock); return; } read_lock(&in6_dev->lock); for (ifp = in6_dev->addr_list; ifp; ifp = ifp->if_next) { /* Add the address to the local list. */ addr = t_new(struct sockaddr_storage_list, GFP_ATOMIC); if (addr) { addr->a.v6.sin6_family = AF_INET6; addr->a.v6.sin6_port = 0; addr->a.v6.sin6_addr = ifp->addr; INIT_LIST_HEAD(&addr->list); list_add_tail(&addr->list, addrlist); } } read_unlock(&in6_dev->lock); read_unlock(&addrconf_lock); } /* 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) { void *from; __u16 *port; struct sctphdr *sh; port = &addr->v6.sin6_port; addr->v6.sin6_family = AF_INET6; addr->v6.sin6_flowinfo = 0; /* FIXME */ addr->v6.sin6_scope_id = 0; /* FIXME */ sh = (struct sctphdr *) skb->h.raw; if (is_saddr) { *port = ntohs(sh->source); from = &skb->nh.ipv6h->saddr; } else { *port = ntohs(sh->dest); from = &skb->nh.ipv6h->daddr; } ipv6_addr_copy(&addr->v6.sin6_addr, from); } /* 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 = inet_sk(sk)->num; addr->v6.sin6_addr = inet6_sk(sk)->rcv_saddr; } /* Initialize sk->rcv_saddr from sctp_addr. */ static void sctp_v6_to_sk(union sctp_addr *addr, struct sock *sk) { inet6_sk(sk)->rcv_saddr = addr->v6.sin6_addr; } /* Initialize a sctp_addr from a dst_entry. */ static void sctp_v6_dst_saddr(union sctp_addr *addr, struct dst_entry *dst, unsigned short port) { struct rt6_info *rt = (struct rt6_info *)dst; addr->sa.sa_family = AF_INET6; addr->v6.sin6_port = port; ipv6_addr_copy(&addr->v6.sin6_addr, &rt->rt6i_src.addr); } /* Compare addresses exactly. Well.. almost exactly; ignore scope_id * for now. FIXME: v4-mapped-v6. */ static int sctp_v6_cmp_addr(const union sctp_addr *addr1, const union sctp_addr *addr2) { int match; if (addr1->sa.sa_family != addr2->sa.sa_family) return 0; match = !ipv6_addr_cmp((struct in6_addr *)&addr1->v6.sin6_addr, (struct in6_addr *)&addr2->v6.sin6_addr); return match; } /* Initialize addr struct to INADDR_ANY. */ static void sctp_v6_inaddr_any(union sctp_addr *addr, unsigned short 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) { int type; type = ipv6_addr_type((struct in6_addr *)&addr->v6.sin6_addr); return IPV6_ADDR_ANY == type; } /* Should this be available for binding? */ static int sctp_v6_available(const union sctp_addr *addr) { int type; struct in6_addr *in6 = (struct in6_addr *)&addr->v6.sin6_addr; type = ipv6_addr_type(in6); if (IPV6_ADDR_ANY == type) return 1; if (!(type & IPV6_ADDR_UNICAST)) return 0; return ipv6_chk_addr(in6, NULL); } /* 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) { int ret = ipv6_addr_type(&addr->v6.sin6_addr); /* FIXME: v4-mapped-v6 address support. */ /* Is this a non-unicast address */ if (!(ret & IPV6_ADDR_UNICAST)) return 0; return 1; } /* What is the scope of 'addr'? */ static sctp_scope_t sctp_v6_scope(union sctp_addr *addr) { int v6scope; sctp_scope_t retval; /* The IPv6 scope is really a set of bit fields. * See IFA_* in <net/if_inet6.h>. 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(). */ struct sock *sctp_v6_create_accept_sk(struct sock *sk, struct sctp_association *asoc) { struct inet_opt *inet = inet_sk(sk); struct sock *newsk; struct inet_opt *newinet; struct ipv6_pinfo *newnp, *np = inet6_sk(sk); struct sctp6_sock *newsctp6sk; newsk = sk_alloc(PF_INET6, GFP_KERNEL, sizeof(struct sctp6_sock), sk->slab); if (!newsk) goto out; sock_init_data(NULL, newsk); newsk->type = SOCK_STREAM; newsk->prot = sk->prot; newsk->no_check = sk->no_check; newsk->reuse = sk->reuse; newsk->destruct = inet_sock_destruct; newsk->zapped = 0; newsk->family = PF_INET6; newsk->protocol = IPPROTO_SCTP; newsk->backlog_rcv = sk->prot->backlog_rcv; newsctp6sk = (struct sctp6_sock *)newsk; newsctp6sk->pinet6 = &newsctp6sk->inet6; newinet = inet_sk(newsk); newnp = inet6_sk(newsk); memcpy(newnp, np, sizeof(struct ipv6_pinfo)); ipv6_addr_copy(&newnp->daddr, &asoc->peer.primary_addr.v6.sin6_addr); newinet->sport = inet->sport; newinet->dport = asoc->peer.port; #ifdef INET_REFCNT_DEBUG atomic_inc(&inet6_sock_nr); atomic_inc(&inet_sock_nr); #endif if (0 != newsk->prot->init(newsk)) { inet_sock_release(newsk); newsk = NULL; } out: return newsk; } /* Initialize a PF_INET6 socket msg_name. */ static void sctp_inet6_msgname(char *msgname, int *addr_len) { struct sockaddr_in6 *sin6; sin6 = (struct sockaddr_in6 *)msgname; sin6->sin6_family = AF_INET6; sin6->sin6_flowinfo = 0; sin6->sin6_scope_id = 0; *addr_len = sizeof(struct sockaddr_in6); } /* Initialize a PF_INET msgname from a ulpevent. */ static void sctp_inet6_event_msgname(struct sctp_ulpevent *event, char *msgname, int *addrlen) { struct sockaddr_in6 *sin6, *sin6from; if (msgname) { union sctp_addr *addr; sctp_inet6_msgname(msgname, addrlen); sin6 = (struct sockaddr_in6 *)msgname; sin6->sin6_port = htons(event->asoc->peer.port); addr = &event->asoc->peer.primary_addr; /* Note: If we go to a common v6 format, this code * will change. */ /* Map ipv4 address into v4-mapped-on-v6 address. */ if (AF_INET == addr->sa.sa_family) { /* FIXME: Easy, but there was no way to test this * yet. */ return; } sin6from = &event->asoc->peer.primary_addr.v6; ipv6_addr_copy(&sin6->sin6_addr, &sin6from->sin6_addr); } } /* Initialize a msg_name from an inbound skb. */ static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname, int *addr_len) { struct sctphdr *sh; struct sockaddr_in6 *sin6; if (msgname) { sctp_inet6_msgname(msgname, addr_len); sin6 = (struct sockaddr_in6 *)msgname; sh = (struct sctphdr *)skb->h.raw; sin6->sin6_port = sh->source; /* FIXME: Map ipv4 address into v4-mapped-on-v6 address. */ if (__constant_htons(ETH_P_IP) == skb->protocol) { /* FIXME: Easy, but there was no way to test this * yet. */ return; } /* Otherwise, just copy the v6 address. */ ipv6_addr_copy(&sin6->sin6_addr, &skb->nh.ipv6h->saddr); if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) { struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb; sin6->sin6_scope_id = opt->iif; } } } /* Do we support this AF? */ static int sctp_inet6_af_supported(sa_family_t family) { /* FIXME: v4-mapped-v6 addresses. The I-D is still waffling * on what to do with sockaddr formats for PF_INET6 sockets. * For now assume we'll support both. */ switch (family) { case AF_INET6: case AF_INET: return 1; 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_opt *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; /* Today, wildcard AF_INET/AF_INET6. */ if (sctp_is_any(addr1) || sctp_is_any(addr2)) return 1; if (addr1->sa.sa_family != addr2->sa.sa_family) return 0; return af1->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_opt *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 af = opt->pf->af; return af->available(addr); } /* 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_opt *opt, __u16 *types) { types[0] = SCTP_PARAM_IPV4_ADDRESS; types[1] = SCTP_PARAM_IPV6_ADDRESS; return 2; } static struct proto_ops inet6_seqpacket_ops = { .family = PF_INET6, .release = inet6_release, .bind = inet6_bind, .connect = inet_dgram_connect, .socketpair = sock_no_socketpair, .accept = inet_accept, .getname = inet6_getname, .poll = sctp_poll, .ioctl = inet6_ioctl, .listen = sctp_inet_listen, .shutdown = inet_shutdown, .setsockopt = inet_setsockopt, .getsockopt = inet_getsockopt, .sendmsg = inet_sendmsg, .recvmsg = inet_recvmsg, .mmap = sock_no_mmap, }; static struct inet_protosw sctpv6_seqpacket_protosw = { .type = SOCK_SEQPACKET, .protocol = IPPROTO_SCTP, .prot = &sctp_prot, .ops = &inet6_seqpacket_ops, .capability = -1, .no_check = 0, .flags = SCTP_PROTOSW_FLAG }; static struct inet_protosw sctpv6_stream_protosw = { .type = SOCK_STREAM, .protocol = IPPROTO_SCTP, .prot = &sctp_prot, .ops = &inet6_seqpacket_ops, .capability = -1, .no_check = 0, .flags = SCTP_PROTOSW_FLAG }; static struct inet6_protocol sctpv6_protocol = { .handler = sctp_rcv, .err_handler = sctp_v6_err, }; static struct sctp_af sctp_ipv6_specific = { .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, .to_sk = sctp_v6_to_sk, .dst_saddr = sctp_v6_dst_saddr, .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, .net_header_len = sizeof(struct ipv6hdr), .sockaddr_len = sizeof(struct sockaddr_in6), .sa_family = AF_INET6, }; static struct sctp_pf sctp_pf_inet6_specific = { .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, .supported_addrs = sctp_inet6_supported_addrs, .create_accept_sk = sctp_v6_create_accept_sk, .af = &sctp_ipv6_specific, }; /* Initialize IPv6 support and register with inet6 stack. */ int sctp_v6_init(void) { /* Register inet6 protocol. */ if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0) return -EAGAIN; /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */ inet6_register_protosw(&sctpv6_seqpacket_protosw); inet6_register_protosw(&sctpv6_stream_protosw); /* Register the SCTP specfic PF_INET6 functions. */ sctp_register_pf(&sctp_pf_inet6_specific, PF_INET6); /* Register the SCTP specfic AF_INET6 functions. */ sctp_register_af(&sctp_ipv6_specific); /* Register notifier for inet6 address additions/deletions. */ register_inet6addr_notifier(&sctp_inetaddr_notifier); return 0; } /* IPv6 specific exit support. */ void sctp_v6_exit(void) { list_del(&sctp_ipv6_specific.list); inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP); inet6_unregister_protosw(&sctpv6_seqpacket_protosw); inet6_unregister_protosw(&sctpv6_stream_protosw); unregister_inet6addr_notifier(&sctp_inetaddr_notifier); }