| /* |
| * DCCP over IPv6 |
| * Linux INET6 implementation |
| * |
| * Based on net/dccp6/ipv6.c |
| * |
| * Arnaldo Carvalho de Melo <acme@ghostprotocols.net> |
| * |
| * This program 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 of the License, or (at your option) any later version. |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/random.h> |
| #include <linux/slab.h> |
| #include <linux/xfrm.h> |
| |
| #include <net/addrconf.h> |
| #include <net/inet_common.h> |
| #include <net/inet_hashtables.h> |
| #include <net/inet_sock.h> |
| #include <net/inet6_connection_sock.h> |
| #include <net/inet6_hashtables.h> |
| #include <net/ip6_route.h> |
| #include <net/ipv6.h> |
| #include <net/protocol.h> |
| #include <net/transp_v6.h> |
| #include <net/ip6_checksum.h> |
| #include <net/xfrm.h> |
| #include <net/secure_seq.h> |
| |
| #include "dccp.h" |
| #include "ipv6.h" |
| #include "feat.h" |
| |
| /* The per-net dccp.v6_ctl_sk is used for sending RSTs and ACKs */ |
| |
| static const struct inet_connection_sock_af_ops dccp_ipv6_mapped; |
| static const struct inet_connection_sock_af_ops dccp_ipv6_af_ops; |
| |
| static void dccp_v6_hash(struct sock *sk) |
| { |
| if (sk->sk_state != DCCP_CLOSED) { |
| if (inet_csk(sk)->icsk_af_ops == &dccp_ipv6_mapped) { |
| inet_hash(sk); |
| return; |
| } |
| local_bh_disable(); |
| __inet6_hash(sk, NULL); |
| local_bh_enable(); |
| } |
| } |
| |
| /* add pseudo-header to DCCP checksum stored in skb->csum */ |
| static inline __sum16 dccp_v6_csum_finish(struct sk_buff *skb, |
| const struct in6_addr *saddr, |
| const struct in6_addr *daddr) |
| { |
| return csum_ipv6_magic(saddr, daddr, skb->len, IPPROTO_DCCP, skb->csum); |
| } |
| |
| static inline void dccp_v6_send_check(struct sock *sk, struct sk_buff *skb) |
| { |
| struct ipv6_pinfo *np = inet6_sk(sk); |
| struct dccp_hdr *dh = dccp_hdr(skb); |
| |
| dccp_csum_outgoing(skb); |
| dh->dccph_checksum = dccp_v6_csum_finish(skb, &np->saddr, &sk->sk_v6_daddr); |
| } |
| |
| static inline __u64 dccp_v6_init_sequence(struct sk_buff *skb) |
| { |
| return secure_dccpv6_sequence_number(ipv6_hdr(skb)->daddr.s6_addr32, |
| ipv6_hdr(skb)->saddr.s6_addr32, |
| dccp_hdr(skb)->dccph_dport, |
| dccp_hdr(skb)->dccph_sport ); |
| |
| } |
| |
| static void dccp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, |
| u8 type, u8 code, int offset, __be32 info) |
| { |
| const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data; |
| const struct dccp_hdr *dh = (struct dccp_hdr *)(skb->data + offset); |
| struct dccp_sock *dp; |
| struct ipv6_pinfo *np; |
| struct sock *sk; |
| int err; |
| __u64 seq; |
| struct net *net = dev_net(skb->dev); |
| |
| if (skb->len < offset + sizeof(*dh) || |
| skb->len < offset + __dccp_basic_hdr_len(dh)) { |
| ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev), |
| ICMP6_MIB_INERRORS); |
| return; |
| } |
| |
| sk = inet6_lookup(net, &dccp_hashinfo, |
| &hdr->daddr, dh->dccph_dport, |
| &hdr->saddr, dh->dccph_sport, inet6_iif(skb)); |
| |
| if (sk == NULL) { |
| ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev), |
| ICMP6_MIB_INERRORS); |
| return; |
| } |
| |
| if (sk->sk_state == DCCP_TIME_WAIT) { |
| inet_twsk_put(inet_twsk(sk)); |
| return; |
| } |
| |
| bh_lock_sock(sk); |
| if (sock_owned_by_user(sk)) |
| NET_INC_STATS_BH(net, LINUX_MIB_LOCKDROPPEDICMPS); |
| |
| if (sk->sk_state == DCCP_CLOSED) |
| goto out; |
| |
| dp = dccp_sk(sk); |
| seq = dccp_hdr_seq(dh); |
| if ((1 << sk->sk_state) & ~(DCCPF_REQUESTING | DCCPF_LISTEN) && |
| !between48(seq, dp->dccps_awl, dp->dccps_awh)) { |
| NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS); |
| goto out; |
| } |
| |
| np = inet6_sk(sk); |
| |
| if (type == NDISC_REDIRECT) { |
| struct dst_entry *dst = __sk_dst_check(sk, np->dst_cookie); |
| |
| if (dst) |
| dst->ops->redirect(dst, sk, skb); |
| goto out; |
| } |
| |
| if (type == ICMPV6_PKT_TOOBIG) { |
| struct dst_entry *dst = NULL; |
| |
| if (!ip6_sk_accept_pmtu(sk)) |
| goto out; |
| |
| if (sock_owned_by_user(sk)) |
| goto out; |
| if ((1 << sk->sk_state) & (DCCPF_LISTEN | DCCPF_CLOSED)) |
| goto out; |
| |
| dst = inet6_csk_update_pmtu(sk, ntohl(info)); |
| if (!dst) |
| goto out; |
| |
| if (inet_csk(sk)->icsk_pmtu_cookie > dst_mtu(dst)) |
| dccp_sync_mss(sk, dst_mtu(dst)); |
| goto out; |
| } |
| |
| icmpv6_err_convert(type, code, &err); |
| |
| /* Might be for an request_sock */ |
| switch (sk->sk_state) { |
| struct request_sock *req, **prev; |
| case DCCP_LISTEN: |
| if (sock_owned_by_user(sk)) |
| goto out; |
| |
| req = inet6_csk_search_req(sk, &prev, dh->dccph_dport, |
| &hdr->daddr, &hdr->saddr, |
| inet6_iif(skb)); |
| if (req == NULL) |
| goto out; |
| |
| /* |
| * ICMPs are not backlogged, hence we cannot get an established |
| * socket here. |
| */ |
| WARN_ON(req->sk != NULL); |
| |
| if (!between48(seq, dccp_rsk(req)->dreq_iss, |
| dccp_rsk(req)->dreq_gss)) { |
| NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS); |
| goto out; |
| } |
| |
| inet_csk_reqsk_queue_drop(sk, req, prev); |
| goto out; |
| |
| case DCCP_REQUESTING: |
| case DCCP_RESPOND: /* Cannot happen. |
| It can, it SYNs are crossed. --ANK */ |
| if (!sock_owned_by_user(sk)) { |
| DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS); |
| sk->sk_err = err; |
| /* |
| * Wake people up to see the error |
| * (see connect in sock.c) |
| */ |
| sk->sk_error_report(sk); |
| dccp_done(sk); |
| } else |
| sk->sk_err_soft = err; |
| goto out; |
| } |
| |
| if (!sock_owned_by_user(sk) && np->recverr) { |
| sk->sk_err = err; |
| sk->sk_error_report(sk); |
| } else |
| sk->sk_err_soft = err; |
| |
| out: |
| bh_unlock_sock(sk); |
| sock_put(sk); |
| } |
| |
| |
| static int dccp_v6_send_response(struct sock *sk, struct request_sock *req) |
| { |
| struct inet_request_sock *ireq = inet_rsk(req); |
| struct ipv6_pinfo *np = inet6_sk(sk); |
| struct sk_buff *skb; |
| struct in6_addr *final_p, final; |
| struct flowi6 fl6; |
| int err = -1; |
| struct dst_entry *dst; |
| |
| memset(&fl6, 0, sizeof(fl6)); |
| fl6.flowi6_proto = IPPROTO_DCCP; |
| fl6.daddr = ireq->ir_v6_rmt_addr; |
| fl6.saddr = ireq->ir_v6_loc_addr; |
| fl6.flowlabel = 0; |
| fl6.flowi6_oif = ireq->ir_iif; |
| fl6.fl6_dport = ireq->ir_rmt_port; |
| fl6.fl6_sport = htons(ireq->ir_num); |
| security_req_classify_flow(req, flowi6_to_flowi(&fl6)); |
| |
| |
| final_p = fl6_update_dst(&fl6, np->opt, &final); |
| |
| dst = ip6_dst_lookup_flow(sk, &fl6, final_p, false); |
| if (IS_ERR(dst)) { |
| err = PTR_ERR(dst); |
| dst = NULL; |
| goto done; |
| } |
| |
| skb = dccp_make_response(sk, dst, req); |
| if (skb != NULL) { |
| struct dccp_hdr *dh = dccp_hdr(skb); |
| |
| dh->dccph_checksum = dccp_v6_csum_finish(skb, |
| &ireq->ir_v6_loc_addr, |
| &ireq->ir_v6_rmt_addr); |
| fl6.daddr = ireq->ir_v6_rmt_addr; |
| err = ip6_xmit(sk, skb, &fl6, np->opt, np->tclass); |
| err = net_xmit_eval(err); |
| } |
| |
| done: |
| dst_release(dst); |
| return err; |
| } |
| |
| static void dccp_v6_reqsk_destructor(struct request_sock *req) |
| { |
| dccp_feat_list_purge(&dccp_rsk(req)->dreq_featneg); |
| kfree_skb(inet_rsk(req)->pktopts); |
| } |
| |
| static void dccp_v6_ctl_send_reset(struct sock *sk, struct sk_buff *rxskb) |
| { |
| const struct ipv6hdr *rxip6h; |
| struct sk_buff *skb; |
| struct flowi6 fl6; |
| struct net *net = dev_net(skb_dst(rxskb)->dev); |
| struct sock *ctl_sk = net->dccp.v6_ctl_sk; |
| struct dst_entry *dst; |
| |
| if (dccp_hdr(rxskb)->dccph_type == DCCP_PKT_RESET) |
| return; |
| |
| if (!ipv6_unicast_destination(rxskb)) |
| return; |
| |
| skb = dccp_ctl_make_reset(ctl_sk, rxskb); |
| if (skb == NULL) |
| return; |
| |
| rxip6h = ipv6_hdr(rxskb); |
| dccp_hdr(skb)->dccph_checksum = dccp_v6_csum_finish(skb, &rxip6h->saddr, |
| &rxip6h->daddr); |
| |
| memset(&fl6, 0, sizeof(fl6)); |
| fl6.daddr = rxip6h->saddr; |
| fl6.saddr = rxip6h->daddr; |
| |
| fl6.flowi6_proto = IPPROTO_DCCP; |
| fl6.flowi6_oif = inet6_iif(rxskb); |
| fl6.fl6_dport = dccp_hdr(skb)->dccph_dport; |
| fl6.fl6_sport = dccp_hdr(skb)->dccph_sport; |
| security_skb_classify_flow(rxskb, flowi6_to_flowi(&fl6)); |
| |
| /* sk = NULL, but it is safe for now. RST socket required. */ |
| dst = ip6_dst_lookup_flow(ctl_sk, &fl6, NULL, false); |
| if (!IS_ERR(dst)) { |
| skb_dst_set(skb, dst); |
| ip6_xmit(ctl_sk, skb, &fl6, NULL, 0); |
| DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS); |
| DCCP_INC_STATS_BH(DCCP_MIB_OUTRSTS); |
| return; |
| } |
| |
| kfree_skb(skb); |
| } |
| |
| static struct request_sock_ops dccp6_request_sock_ops = { |
| .family = AF_INET6, |
| .obj_size = sizeof(struct dccp6_request_sock), |
| .rtx_syn_ack = dccp_v6_send_response, |
| .send_ack = dccp_reqsk_send_ack, |
| .destructor = dccp_v6_reqsk_destructor, |
| .send_reset = dccp_v6_ctl_send_reset, |
| .syn_ack_timeout = dccp_syn_ack_timeout, |
| }; |
| |
| static struct sock *dccp_v6_hnd_req(struct sock *sk,struct sk_buff *skb) |
| { |
| const struct dccp_hdr *dh = dccp_hdr(skb); |
| const struct ipv6hdr *iph = ipv6_hdr(skb); |
| struct sock *nsk; |
| struct request_sock **prev; |
| /* Find possible connection requests. */ |
| struct request_sock *req = inet6_csk_search_req(sk, &prev, |
| dh->dccph_sport, |
| &iph->saddr, |
| &iph->daddr, |
| inet6_iif(skb)); |
| if (req != NULL) |
| return dccp_check_req(sk, skb, req, prev); |
| |
| nsk = __inet6_lookup_established(sock_net(sk), &dccp_hashinfo, |
| &iph->saddr, dh->dccph_sport, |
| &iph->daddr, ntohs(dh->dccph_dport), |
| inet6_iif(skb)); |
| if (nsk != NULL) { |
| if (nsk->sk_state != DCCP_TIME_WAIT) { |
| bh_lock_sock(nsk); |
| return nsk; |
| } |
| inet_twsk_put(inet_twsk(nsk)); |
| return NULL; |
| } |
| |
| return sk; |
| } |
| |
| static int dccp_v6_conn_request(struct sock *sk, struct sk_buff *skb) |
| { |
| struct request_sock *req; |
| struct dccp_request_sock *dreq; |
| struct inet_request_sock *ireq; |
| struct ipv6_pinfo *np = inet6_sk(sk); |
| const __be32 service = dccp_hdr_request(skb)->dccph_req_service; |
| struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb); |
| |
| if (skb->protocol == htons(ETH_P_IP)) |
| return dccp_v4_conn_request(sk, skb); |
| |
| if (!ipv6_unicast_destination(skb)) |
| return 0; /* discard, don't send a reset here */ |
| |
| if (dccp_bad_service_code(sk, service)) { |
| dcb->dccpd_reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE; |
| goto drop; |
| } |
| /* |
| * There are no SYN attacks on IPv6, yet... |
| */ |
| dcb->dccpd_reset_code = DCCP_RESET_CODE_TOO_BUSY; |
| if (inet_csk_reqsk_queue_is_full(sk)) |
| goto drop; |
| |
| if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1) |
| goto drop; |
| |
| req = inet6_reqsk_alloc(&dccp6_request_sock_ops); |
| if (req == NULL) |
| goto drop; |
| |
| if (dccp_reqsk_init(req, dccp_sk(sk), skb)) |
| goto drop_and_free; |
| |
| dreq = dccp_rsk(req); |
| if (dccp_parse_options(sk, dreq, skb)) |
| goto drop_and_free; |
| |
| if (security_inet_conn_request(sk, skb, req)) |
| goto drop_and_free; |
| |
| ireq = inet_rsk(req); |
| ireq->ir_v6_rmt_addr = ipv6_hdr(skb)->saddr; |
| ireq->ir_v6_loc_addr = ipv6_hdr(skb)->daddr; |
| |
| if (ipv6_opt_accepted(sk, skb) || |
| np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo || |
| np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) { |
| atomic_inc(&skb->users); |
| ireq->pktopts = skb; |
| } |
| ireq->ir_iif = sk->sk_bound_dev_if; |
| |
| /* So that link locals have meaning */ |
| if (!sk->sk_bound_dev_if && |
| ipv6_addr_type(&ireq->ir_v6_rmt_addr) & IPV6_ADDR_LINKLOCAL) |
| ireq->ir_iif = inet6_iif(skb); |
| |
| /* |
| * Step 3: Process LISTEN state |
| * |
| * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie |
| * |
| * Setting S.SWL/S.SWH to is deferred to dccp_create_openreq_child(). |
| */ |
| dreq->dreq_isr = dcb->dccpd_seq; |
| dreq->dreq_gsr = dreq->dreq_isr; |
| dreq->dreq_iss = dccp_v6_init_sequence(skb); |
| dreq->dreq_gss = dreq->dreq_iss; |
| dreq->dreq_service = service; |
| |
| if (dccp_v6_send_response(sk, req)) |
| goto drop_and_free; |
| |
| inet6_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT); |
| return 0; |
| |
| drop_and_free: |
| reqsk_free(req); |
| drop: |
| DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS); |
| return -1; |
| } |
| |
| static struct sock *dccp_v6_request_recv_sock(struct sock *sk, |
| struct sk_buff *skb, |
| struct request_sock *req, |
| struct dst_entry *dst) |
| { |
| struct inet_request_sock *ireq = inet_rsk(req); |
| struct ipv6_pinfo *newnp, *np = inet6_sk(sk); |
| struct inet_sock *newinet; |
| struct dccp6_sock *newdp6; |
| struct sock *newsk; |
| |
| if (skb->protocol == htons(ETH_P_IP)) { |
| /* |
| * v6 mapped |
| */ |
| newsk = dccp_v4_request_recv_sock(sk, skb, req, dst); |
| if (newsk == NULL) |
| return NULL; |
| |
| newdp6 = (struct dccp6_sock *)newsk; |
| newinet = inet_sk(newsk); |
| newinet->pinet6 = &newdp6->inet6; |
| newnp = inet6_sk(newsk); |
| |
| memcpy(newnp, np, sizeof(struct ipv6_pinfo)); |
| |
| ipv6_addr_set_v4mapped(newinet->inet_daddr, &newsk->sk_v6_daddr); |
| |
| ipv6_addr_set_v4mapped(newinet->inet_saddr, &newnp->saddr); |
| |
| newsk->sk_v6_rcv_saddr = newnp->saddr; |
| |
| inet_csk(newsk)->icsk_af_ops = &dccp_ipv6_mapped; |
| newsk->sk_backlog_rcv = dccp_v4_do_rcv; |
| newnp->pktoptions = NULL; |
| newnp->opt = NULL; |
| newnp->mcast_oif = inet6_iif(skb); |
| newnp->mcast_hops = ipv6_hdr(skb)->hop_limit; |
| |
| /* |
| * No need to charge this sock to the relevant IPv6 refcnt debug socks count |
| * here, dccp_create_openreq_child now does this for us, see the comment in |
| * that function for the gory details. -acme |
| */ |
| |
| /* It is tricky place. Until this moment IPv4 tcp |
| worked with IPv6 icsk.icsk_af_ops. |
| Sync it now. |
| */ |
| dccp_sync_mss(newsk, inet_csk(newsk)->icsk_pmtu_cookie); |
| |
| return newsk; |
| } |
| |
| |
| if (sk_acceptq_is_full(sk)) |
| goto out_overflow; |
| |
| if (dst == NULL) { |
| struct in6_addr *final_p, final; |
| struct flowi6 fl6; |
| |
| memset(&fl6, 0, sizeof(fl6)); |
| fl6.flowi6_proto = IPPROTO_DCCP; |
| fl6.daddr = ireq->ir_v6_rmt_addr; |
| final_p = fl6_update_dst(&fl6, np->opt, &final); |
| fl6.saddr = ireq->ir_v6_loc_addr; |
| fl6.flowi6_oif = sk->sk_bound_dev_if; |
| fl6.fl6_dport = ireq->ir_rmt_port; |
| fl6.fl6_sport = htons(ireq->ir_num); |
| security_sk_classify_flow(sk, flowi6_to_flowi(&fl6)); |
| |
| dst = ip6_dst_lookup_flow(sk, &fl6, final_p, false); |
| if (IS_ERR(dst)) |
| goto out; |
| } |
| |
| newsk = dccp_create_openreq_child(sk, req, skb); |
| if (newsk == NULL) |
| goto out_nonewsk; |
| |
| /* |
| * No need to charge this sock to the relevant IPv6 refcnt debug socks |
| * count here, dccp_create_openreq_child now does this for us, see the |
| * comment in that function for the gory details. -acme |
| */ |
| |
| __ip6_dst_store(newsk, dst, NULL, NULL); |
| newsk->sk_route_caps = dst->dev->features & ~(NETIF_F_IP_CSUM | |
| NETIF_F_TSO); |
| newdp6 = (struct dccp6_sock *)newsk; |
| newinet = inet_sk(newsk); |
| newinet->pinet6 = &newdp6->inet6; |
| newnp = inet6_sk(newsk); |
| |
| memcpy(newnp, np, sizeof(struct ipv6_pinfo)); |
| |
| newsk->sk_v6_daddr = ireq->ir_v6_rmt_addr; |
| newnp->saddr = ireq->ir_v6_loc_addr; |
| newsk->sk_v6_rcv_saddr = ireq->ir_v6_loc_addr; |
| newsk->sk_bound_dev_if = ireq->ir_iif; |
| |
| /* Now IPv6 options... |
| |
| First: no IPv4 options. |
| */ |
| newinet->inet_opt = NULL; |
| |
| /* Clone RX bits */ |
| newnp->rxopt.all = np->rxopt.all; |
| |
| /* Clone pktoptions received with SYN */ |
| newnp->pktoptions = NULL; |
| if (ireq->pktopts != NULL) { |
| newnp->pktoptions = skb_clone(ireq->pktopts, GFP_ATOMIC); |
| consume_skb(ireq->pktopts); |
| ireq->pktopts = NULL; |
| if (newnp->pktoptions) |
| skb_set_owner_r(newnp->pktoptions, newsk); |
| } |
| newnp->opt = NULL; |
| newnp->mcast_oif = inet6_iif(skb); |
| newnp->mcast_hops = ipv6_hdr(skb)->hop_limit; |
| |
| /* |
| * Clone native IPv6 options from listening socket (if any) |
| * |
| * Yes, keeping reference count would be much more clever, but we make |
| * one more one thing there: reattach optmem to newsk. |
| */ |
| if (np->opt != NULL) |
| newnp->opt = ipv6_dup_options(newsk, np->opt); |
| |
| inet_csk(newsk)->icsk_ext_hdr_len = 0; |
| if (newnp->opt != NULL) |
| inet_csk(newsk)->icsk_ext_hdr_len = (newnp->opt->opt_nflen + |
| newnp->opt->opt_flen); |
| |
| dccp_sync_mss(newsk, dst_mtu(dst)); |
| |
| newinet->inet_daddr = newinet->inet_saddr = LOOPBACK4_IPV6; |
| newinet->inet_rcv_saddr = LOOPBACK4_IPV6; |
| |
| if (__inet_inherit_port(sk, newsk) < 0) { |
| inet_csk_prepare_forced_close(newsk); |
| dccp_done(newsk); |
| goto out; |
| } |
| __inet6_hash(newsk, NULL); |
| |
| return newsk; |
| |
| out_overflow: |
| NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS); |
| out_nonewsk: |
| dst_release(dst); |
| out: |
| NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS); |
| return NULL; |
| } |
| |
| /* The socket must have it's spinlock held when we get |
| * here. |
| * |
| * We have a potential double-lock case here, so even when |
| * doing backlog processing we use the BH locking scheme. |
| * This is because we cannot sleep with the original spinlock |
| * held. |
| */ |
| static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) |
| { |
| struct ipv6_pinfo *np = inet6_sk(sk); |
| struct sk_buff *opt_skb = NULL; |
| |
| /* Imagine: socket is IPv6. IPv4 packet arrives, |
| goes to IPv4 receive handler and backlogged. |
| From backlog it always goes here. Kerboom... |
| Fortunately, dccp_rcv_established and rcv_established |
| handle them correctly, but it is not case with |
| dccp_v6_hnd_req and dccp_v6_ctl_send_reset(). --ANK |
| */ |
| |
| if (skb->protocol == htons(ETH_P_IP)) |
| return dccp_v4_do_rcv(sk, skb); |
| |
| if (sk_filter(sk, skb)) |
| goto discard; |
| |
| /* |
| * socket locking is here for SMP purposes as backlog rcv is currently |
| * called with bh processing disabled. |
| */ |
| |
| /* Do Stevens' IPV6_PKTOPTIONS. |
| |
| Yes, guys, it is the only place in our code, where we |
| may make it not affecting IPv4. |
| The rest of code is protocol independent, |
| and I do not like idea to uglify IPv4. |
| |
| Actually, all the idea behind IPV6_PKTOPTIONS |
| looks not very well thought. For now we latch |
| options, received in the last packet, enqueued |
| by tcp. Feel free to propose better solution. |
| --ANK (980728) |
| */ |
| if (np->rxopt.all) |
| /* |
| * FIXME: Add handling of IPV6_PKTOPTIONS skb. See the comments below |
| * (wrt ipv6_pktopions) and net/ipv6/tcp_ipv6.c for an example. |
| */ |
| opt_skb = skb_clone(skb, GFP_ATOMIC); |
| |
| if (sk->sk_state == DCCP_OPEN) { /* Fast path */ |
| if (dccp_rcv_established(sk, skb, dccp_hdr(skb), skb->len)) |
| goto reset; |
| if (opt_skb) { |
| /* XXX This is where we would goto ipv6_pktoptions. */ |
| __kfree_skb(opt_skb); |
| } |
| return 0; |
| } |
| |
| /* |
| * Step 3: Process LISTEN state |
| * If S.state == LISTEN, |
| * If P.type == Request or P contains a valid Init Cookie option, |
| * (* Must scan the packet's options to check for Init |
| * Cookies. Only Init Cookies are processed here, |
| * however; other options are processed in Step 8. This |
| * scan need only be performed if the endpoint uses Init |
| * Cookies *) |
| * (* Generate a new socket and switch to that socket *) |
| * Set S := new socket for this port pair |
| * S.state = RESPOND |
| * Choose S.ISS (initial seqno) or set from Init Cookies |
| * Initialize S.GAR := S.ISS |
| * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookies |
| * Continue with S.state == RESPOND |
| * (* A Response packet will be generated in Step 11 *) |
| * Otherwise, |
| * Generate Reset(No Connection) unless P.type == Reset |
| * Drop packet and return |
| * |
| * NOTE: the check for the packet types is done in |
| * dccp_rcv_state_process |
| */ |
| if (sk->sk_state == DCCP_LISTEN) { |
| struct sock *nsk = dccp_v6_hnd_req(sk, skb); |
| |
| if (nsk == NULL) |
| goto discard; |
| /* |
| * Queue it on the new socket if the new socket is active, |
| * otherwise we just shortcircuit this and continue with |
| * the new socket.. |
| */ |
| if (nsk != sk) { |
| if (dccp_child_process(sk, nsk, skb)) |
| goto reset; |
| if (opt_skb != NULL) |
| __kfree_skb(opt_skb); |
| return 0; |
| } |
| } |
| |
| if (dccp_rcv_state_process(sk, skb, dccp_hdr(skb), skb->len)) |
| goto reset; |
| if (opt_skb) { |
| /* XXX This is where we would goto ipv6_pktoptions. */ |
| __kfree_skb(opt_skb); |
| } |
| return 0; |
| |
| reset: |
| dccp_v6_ctl_send_reset(sk, skb); |
| discard: |
| if (opt_skb != NULL) |
| __kfree_skb(opt_skb); |
| kfree_skb(skb); |
| return 0; |
| } |
| |
| static int dccp_v6_rcv(struct sk_buff *skb) |
| { |
| const struct dccp_hdr *dh; |
| struct sock *sk; |
| int min_cov; |
| |
| /* Step 1: Check header basics */ |
| |
| if (dccp_invalid_packet(skb)) |
| goto discard_it; |
| |
| /* Step 1: If header checksum is incorrect, drop packet and return. */ |
| if (dccp_v6_csum_finish(skb, &ipv6_hdr(skb)->saddr, |
| &ipv6_hdr(skb)->daddr)) { |
| DCCP_WARN("dropped packet with invalid checksum\n"); |
| goto discard_it; |
| } |
| |
| dh = dccp_hdr(skb); |
| |
| DCCP_SKB_CB(skb)->dccpd_seq = dccp_hdr_seq(dh); |
| DCCP_SKB_CB(skb)->dccpd_type = dh->dccph_type; |
| |
| if (dccp_packet_without_ack(skb)) |
| DCCP_SKB_CB(skb)->dccpd_ack_seq = DCCP_PKT_WITHOUT_ACK_SEQ; |
| else |
| DCCP_SKB_CB(skb)->dccpd_ack_seq = dccp_hdr_ack_seq(skb); |
| |
| /* Step 2: |
| * Look up flow ID in table and get corresponding socket */ |
| sk = __inet6_lookup_skb(&dccp_hashinfo, skb, |
| dh->dccph_sport, dh->dccph_dport); |
| /* |
| * Step 2: |
| * If no socket ... |
| */ |
| if (sk == NULL) { |
| dccp_pr_debug("failed to look up flow ID in table and " |
| "get corresponding socket\n"); |
| goto no_dccp_socket; |
| } |
| |
| /* |
| * Step 2: |
| * ... or S.state == TIMEWAIT, |
| * Generate Reset(No Connection) unless P.type == Reset |
| * Drop packet and return |
| */ |
| if (sk->sk_state == DCCP_TIME_WAIT) { |
| dccp_pr_debug("sk->sk_state == DCCP_TIME_WAIT: do_time_wait\n"); |
| inet_twsk_put(inet_twsk(sk)); |
| goto no_dccp_socket; |
| } |
| |
| /* |
| * RFC 4340, sec. 9.2.1: Minimum Checksum Coverage |
| * o if MinCsCov = 0, only packets with CsCov = 0 are accepted |
| * o if MinCsCov > 0, also accept packets with CsCov >= MinCsCov |
| */ |
| min_cov = dccp_sk(sk)->dccps_pcrlen; |
| if (dh->dccph_cscov && (min_cov == 0 || dh->dccph_cscov < min_cov)) { |
| dccp_pr_debug("Packet CsCov %d does not satisfy MinCsCov %d\n", |
| dh->dccph_cscov, min_cov); |
| /* FIXME: send Data Dropped option (see also dccp_v4_rcv) */ |
| goto discard_and_relse; |
| } |
| |
| if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) |
| goto discard_and_relse; |
| |
| return sk_receive_skb(sk, skb, 1) ? -1 : 0; |
| |
| no_dccp_socket: |
| if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) |
| goto discard_it; |
| /* |
| * Step 2: |
| * If no socket ... |
| * Generate Reset(No Connection) unless P.type == Reset |
| * Drop packet and return |
| */ |
| if (dh->dccph_type != DCCP_PKT_RESET) { |
| DCCP_SKB_CB(skb)->dccpd_reset_code = |
| DCCP_RESET_CODE_NO_CONNECTION; |
| dccp_v6_ctl_send_reset(sk, skb); |
| } |
| |
| discard_it: |
| kfree_skb(skb); |
| return 0; |
| |
| discard_and_relse: |
| sock_put(sk); |
| goto discard_it; |
| } |
| |
| static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr, |
| int addr_len) |
| { |
| struct sockaddr_in6 *usin = (struct sockaddr_in6 *)uaddr; |
| struct inet_connection_sock *icsk = inet_csk(sk); |
| struct inet_sock *inet = inet_sk(sk); |
| struct ipv6_pinfo *np = inet6_sk(sk); |
| struct dccp_sock *dp = dccp_sk(sk); |
| struct in6_addr *saddr = NULL, *final_p, final; |
| struct flowi6 fl6; |
| struct dst_entry *dst; |
| int addr_type; |
| int err; |
| |
| dp->dccps_role = DCCP_ROLE_CLIENT; |
| |
| if (addr_len < SIN6_LEN_RFC2133) |
| return -EINVAL; |
| |
| if (usin->sin6_family != AF_INET6) |
| return -EAFNOSUPPORT; |
| |
| memset(&fl6, 0, sizeof(fl6)); |
| |
| if (np->sndflow) { |
| fl6.flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK; |
| IP6_ECN_flow_init(fl6.flowlabel); |
| if (fl6.flowlabel & IPV6_FLOWLABEL_MASK) { |
| struct ip6_flowlabel *flowlabel; |
| flowlabel = fl6_sock_lookup(sk, fl6.flowlabel); |
| if (flowlabel == NULL) |
| return -EINVAL; |
| fl6_sock_release(flowlabel); |
| } |
| } |
| /* |
| * connect() to INADDR_ANY means loopback (BSD'ism). |
| */ |
| if (ipv6_addr_any(&usin->sin6_addr)) |
| usin->sin6_addr.s6_addr[15] = 1; |
| |
| addr_type = ipv6_addr_type(&usin->sin6_addr); |
| |
| if (addr_type & IPV6_ADDR_MULTICAST) |
| return -ENETUNREACH; |
| |
| if (addr_type & IPV6_ADDR_LINKLOCAL) { |
| if (addr_len >= sizeof(struct sockaddr_in6) && |
| usin->sin6_scope_id) { |
| /* If interface is set while binding, indices |
| * must coincide. |
| */ |
| if (sk->sk_bound_dev_if && |
| sk->sk_bound_dev_if != usin->sin6_scope_id) |
| return -EINVAL; |
| |
| sk->sk_bound_dev_if = usin->sin6_scope_id; |
| } |
| |
| /* Connect to link-local address requires an interface */ |
| if (!sk->sk_bound_dev_if) |
| return -EINVAL; |
| } |
| |
| sk->sk_v6_daddr = usin->sin6_addr; |
| np->flow_label = fl6.flowlabel; |
| |
| /* |
| * DCCP over IPv4 |
| */ |
| if (addr_type == IPV6_ADDR_MAPPED) { |
| u32 exthdrlen = icsk->icsk_ext_hdr_len; |
| struct sockaddr_in sin; |
| |
| SOCK_DEBUG(sk, "connect: ipv4 mapped\n"); |
| |
| if (__ipv6_only_sock(sk)) |
| return -ENETUNREACH; |
| |
| sin.sin_family = AF_INET; |
| sin.sin_port = usin->sin6_port; |
| sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3]; |
| |
| icsk->icsk_af_ops = &dccp_ipv6_mapped; |
| sk->sk_backlog_rcv = dccp_v4_do_rcv; |
| |
| err = dccp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin)); |
| if (err) { |
| icsk->icsk_ext_hdr_len = exthdrlen; |
| icsk->icsk_af_ops = &dccp_ipv6_af_ops; |
| sk->sk_backlog_rcv = dccp_v6_do_rcv; |
| goto failure; |
| } |
| ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr); |
| ipv6_addr_set_v4mapped(inet->inet_rcv_saddr, &sk->sk_v6_rcv_saddr); |
| |
| return err; |
| } |
| |
| if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr)) |
| saddr = &sk->sk_v6_rcv_saddr; |
| |
| fl6.flowi6_proto = IPPROTO_DCCP; |
| fl6.daddr = sk->sk_v6_daddr; |
| fl6.saddr = saddr ? *saddr : np->saddr; |
| fl6.flowi6_oif = sk->sk_bound_dev_if; |
| fl6.fl6_dport = usin->sin6_port; |
| fl6.fl6_sport = inet->inet_sport; |
| security_sk_classify_flow(sk, flowi6_to_flowi(&fl6)); |
| |
| final_p = fl6_update_dst(&fl6, np->opt, &final); |
| |
| dst = ip6_dst_lookup_flow(sk, &fl6, final_p, true); |
| if (IS_ERR(dst)) { |
| err = PTR_ERR(dst); |
| goto failure; |
| } |
| |
| if (saddr == NULL) { |
| saddr = &fl6.saddr; |
| sk->sk_v6_rcv_saddr = *saddr; |
| } |
| |
| /* set the source address */ |
| np->saddr = *saddr; |
| inet->inet_rcv_saddr = LOOPBACK4_IPV6; |
| |
| __ip6_dst_store(sk, dst, NULL, NULL); |
| |
| icsk->icsk_ext_hdr_len = 0; |
| if (np->opt != NULL) |
| icsk->icsk_ext_hdr_len = (np->opt->opt_flen + |
| np->opt->opt_nflen); |
| |
| inet->inet_dport = usin->sin6_port; |
| |
| dccp_set_state(sk, DCCP_REQUESTING); |
| err = inet6_hash_connect(&dccp_death_row, sk); |
| if (err) |
| goto late_failure; |
| |
| dp->dccps_iss = secure_dccpv6_sequence_number(np->saddr.s6_addr32, |
| sk->sk_v6_daddr.s6_addr32, |
| inet->inet_sport, |
| inet->inet_dport); |
| err = dccp_connect(sk); |
| if (err) |
| goto late_failure; |
| |
| return 0; |
| |
| late_failure: |
| dccp_set_state(sk, DCCP_CLOSED); |
| __sk_dst_reset(sk); |
| failure: |
| inet->inet_dport = 0; |
| sk->sk_route_caps = 0; |
| return err; |
| } |
| |
| static const struct inet_connection_sock_af_ops dccp_ipv6_af_ops = { |
| .queue_xmit = inet6_csk_xmit, |
| .send_check = dccp_v6_send_check, |
| .rebuild_header = inet6_sk_rebuild_header, |
| .conn_request = dccp_v6_conn_request, |
| .syn_recv_sock = dccp_v6_request_recv_sock, |
| .net_header_len = sizeof(struct ipv6hdr), |
| .setsockopt = ipv6_setsockopt, |
| .getsockopt = ipv6_getsockopt, |
| .addr2sockaddr = inet6_csk_addr2sockaddr, |
| .sockaddr_len = sizeof(struct sockaddr_in6), |
| .bind_conflict = inet6_csk_bind_conflict, |
| #ifdef CONFIG_COMPAT |
| .compat_setsockopt = compat_ipv6_setsockopt, |
| .compat_getsockopt = compat_ipv6_getsockopt, |
| #endif |
| }; |
| |
| /* |
| * DCCP over IPv4 via INET6 API |
| */ |
| static const struct inet_connection_sock_af_ops dccp_ipv6_mapped = { |
| .queue_xmit = ip_queue_xmit, |
| .send_check = dccp_v4_send_check, |
| .rebuild_header = inet_sk_rebuild_header, |
| .conn_request = dccp_v6_conn_request, |
| .syn_recv_sock = dccp_v6_request_recv_sock, |
| .net_header_len = sizeof(struct iphdr), |
| .setsockopt = ipv6_setsockopt, |
| .getsockopt = ipv6_getsockopt, |
| .addr2sockaddr = inet6_csk_addr2sockaddr, |
| .sockaddr_len = sizeof(struct sockaddr_in6), |
| #ifdef CONFIG_COMPAT |
| .compat_setsockopt = compat_ipv6_setsockopt, |
| .compat_getsockopt = compat_ipv6_getsockopt, |
| #endif |
| }; |
| |
| /* NOTE: A lot of things set to zero explicitly by call to |
| * sk_alloc() so need not be done here. |
| */ |
| static int dccp_v6_init_sock(struct sock *sk) |
| { |
| static __u8 dccp_v6_ctl_sock_initialized; |
| int err = dccp_init_sock(sk, dccp_v6_ctl_sock_initialized); |
| |
| if (err == 0) { |
| if (unlikely(!dccp_v6_ctl_sock_initialized)) |
| dccp_v6_ctl_sock_initialized = 1; |
| inet_csk(sk)->icsk_af_ops = &dccp_ipv6_af_ops; |
| } |
| |
| return err; |
| } |
| |
| static void dccp_v6_destroy_sock(struct sock *sk) |
| { |
| dccp_destroy_sock(sk); |
| inet6_destroy_sock(sk); |
| } |
| |
| static struct timewait_sock_ops dccp6_timewait_sock_ops = { |
| .twsk_obj_size = sizeof(struct dccp6_timewait_sock), |
| }; |
| |
| static struct proto dccp_v6_prot = { |
| .name = "DCCPv6", |
| .owner = THIS_MODULE, |
| .close = dccp_close, |
| .connect = dccp_v6_connect, |
| .disconnect = dccp_disconnect, |
| .ioctl = dccp_ioctl, |
| .init = dccp_v6_init_sock, |
| .setsockopt = dccp_setsockopt, |
| .getsockopt = dccp_getsockopt, |
| .sendmsg = dccp_sendmsg, |
| .recvmsg = dccp_recvmsg, |
| .backlog_rcv = dccp_v6_do_rcv, |
| .hash = dccp_v6_hash, |
| .unhash = inet_unhash, |
| .accept = inet_csk_accept, |
| .get_port = inet_csk_get_port, |
| .shutdown = dccp_shutdown, |
| .destroy = dccp_v6_destroy_sock, |
| .orphan_count = &dccp_orphan_count, |
| .max_header = MAX_DCCP_HEADER, |
| .obj_size = sizeof(struct dccp6_sock), |
| .slab_flags = SLAB_DESTROY_BY_RCU, |
| .rsk_prot = &dccp6_request_sock_ops, |
| .twsk_prot = &dccp6_timewait_sock_ops, |
| .h.hashinfo = &dccp_hashinfo, |
| #ifdef CONFIG_COMPAT |
| .compat_setsockopt = compat_dccp_setsockopt, |
| .compat_getsockopt = compat_dccp_getsockopt, |
| #endif |
| }; |
| |
| static const struct inet6_protocol dccp_v6_protocol = { |
| .handler = dccp_v6_rcv, |
| .err_handler = dccp_v6_err, |
| .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL, |
| }; |
| |
| static const struct proto_ops inet6_dccp_ops = { |
| .family = PF_INET6, |
| .owner = THIS_MODULE, |
| .release = inet6_release, |
| .bind = inet6_bind, |
| .connect = inet_stream_connect, |
| .socketpair = sock_no_socketpair, |
| .accept = inet_accept, |
| .getname = inet6_getname, |
| .poll = dccp_poll, |
| .ioctl = inet6_ioctl, |
| .listen = inet_dccp_listen, |
| .shutdown = inet_shutdown, |
| .setsockopt = sock_common_setsockopt, |
| .getsockopt = sock_common_getsockopt, |
| .sendmsg = inet_sendmsg, |
| .recvmsg = sock_common_recvmsg, |
| .mmap = sock_no_mmap, |
| .sendpage = sock_no_sendpage, |
| #ifdef CONFIG_COMPAT |
| .compat_setsockopt = compat_sock_common_setsockopt, |
| .compat_getsockopt = compat_sock_common_getsockopt, |
| #endif |
| }; |
| |
| static struct inet_protosw dccp_v6_protosw = { |
| .type = SOCK_DCCP, |
| .protocol = IPPROTO_DCCP, |
| .prot = &dccp_v6_prot, |
| .ops = &inet6_dccp_ops, |
| .flags = INET_PROTOSW_ICSK, |
| }; |
| |
| static int __net_init dccp_v6_init_net(struct net *net) |
| { |
| if (dccp_hashinfo.bhash == NULL) |
| return -ESOCKTNOSUPPORT; |
| |
| return inet_ctl_sock_create(&net->dccp.v6_ctl_sk, PF_INET6, |
| SOCK_DCCP, IPPROTO_DCCP, net); |
| } |
| |
| static void __net_exit dccp_v6_exit_net(struct net *net) |
| { |
| inet_ctl_sock_destroy(net->dccp.v6_ctl_sk); |
| } |
| |
| static struct pernet_operations dccp_v6_ops = { |
| .init = dccp_v6_init_net, |
| .exit = dccp_v6_exit_net, |
| }; |
| |
| static int __init dccp_v6_init(void) |
| { |
| int err = proto_register(&dccp_v6_prot, 1); |
| |
| if (err != 0) |
| goto out; |
| |
| err = inet6_add_protocol(&dccp_v6_protocol, IPPROTO_DCCP); |
| if (err != 0) |
| goto out_unregister_proto; |
| |
| inet6_register_protosw(&dccp_v6_protosw); |
| |
| err = register_pernet_subsys(&dccp_v6_ops); |
| if (err != 0) |
| goto out_destroy_ctl_sock; |
| out: |
| return err; |
| |
| out_destroy_ctl_sock: |
| inet6_del_protocol(&dccp_v6_protocol, IPPROTO_DCCP); |
| inet6_unregister_protosw(&dccp_v6_protosw); |
| out_unregister_proto: |
| proto_unregister(&dccp_v6_prot); |
| goto out; |
| } |
| |
| static void __exit dccp_v6_exit(void) |
| { |
| unregister_pernet_subsys(&dccp_v6_ops); |
| inet6_del_protocol(&dccp_v6_protocol, IPPROTO_DCCP); |
| inet6_unregister_protosw(&dccp_v6_protosw); |
| proto_unregister(&dccp_v6_prot); |
| } |
| |
| module_init(dccp_v6_init); |
| module_exit(dccp_v6_exit); |
| |
| /* |
| * __stringify doesn't likes enums, so use SOCK_DCCP (6) and IPPROTO_DCCP (33) |
| * values directly, Also cover the case where the protocol is not specified, |
| * i.e. net-pf-PF_INET6-proto-0-type-SOCK_DCCP |
| */ |
| MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET6, 33, 6); |
| MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET6, 0, 6); |
| MODULE_LICENSE("GPL"); |
| MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@mandriva.com>"); |
| MODULE_DESCRIPTION("DCCPv6 - Datagram Congestion Controlled Protocol"); |