1110 lines
29 KiB
C
1110 lines
29 KiB
C
/*
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* DCCP over IPv6
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* Linux INET6 implementation
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*
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* Based on net/dccp6/ipv6.c
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*
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* Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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#include <linux/module.h>
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#include <linux/random.h>
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#include <linux/slab.h>
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#include <linux/xfrm.h>
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#include <net/addrconf.h>
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#include <net/inet_common.h>
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#include <net/inet_hashtables.h>
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#include <net/inet_sock.h>
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#include <net/inet6_connection_sock.h>
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#include <net/inet6_hashtables.h>
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#include <net/ip6_route.h>
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#include <net/ipv6.h>
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#include <net/protocol.h>
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#include <net/transp_v6.h>
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#include <net/ip6_checksum.h>
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#include <net/xfrm.h>
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#include <net/secure_seq.h>
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#include "dccp.h"
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#include "ipv6.h"
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#include "feat.h"
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/* The per-net dccp.v6_ctl_sk is used for sending RSTs and ACKs */
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static const struct inet_connection_sock_af_ops dccp_ipv6_mapped;
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static const struct inet_connection_sock_af_ops dccp_ipv6_af_ops;
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/* add pseudo-header to DCCP checksum stored in skb->csum */
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static inline __sum16 dccp_v6_csum_finish(struct sk_buff *skb,
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const struct in6_addr *saddr,
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const struct in6_addr *daddr)
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{
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return csum_ipv6_magic(saddr, daddr, skb->len, IPPROTO_DCCP, skb->csum);
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}
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static inline void dccp_v6_send_check(struct sock *sk, struct sk_buff *skb)
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{
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struct ipv6_pinfo *np = inet6_sk(sk);
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struct dccp_hdr *dh = dccp_hdr(skb);
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dccp_csum_outgoing(skb);
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dh->dccph_checksum = dccp_v6_csum_finish(skb, &np->saddr, &sk->sk_v6_daddr);
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}
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static inline __u64 dccp_v6_init_sequence(struct sk_buff *skb)
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{
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return secure_dccpv6_sequence_number(ipv6_hdr(skb)->daddr.s6_addr32,
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ipv6_hdr(skb)->saddr.s6_addr32,
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dccp_hdr(skb)->dccph_dport,
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dccp_hdr(skb)->dccph_sport );
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}
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static void dccp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
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u8 type, u8 code, int offset, __be32 info)
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{
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const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data;
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const struct dccp_hdr *dh = (struct dccp_hdr *)(skb->data + offset);
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struct dccp_sock *dp;
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struct ipv6_pinfo *np;
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struct sock *sk;
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int err;
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__u64 seq;
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struct net *net = dev_net(skb->dev);
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if (skb->len < offset + sizeof(*dh) ||
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skb->len < offset + __dccp_basic_hdr_len(dh)) {
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ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev),
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ICMP6_MIB_INERRORS);
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return;
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}
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sk = __inet6_lookup_established(net, &dccp_hashinfo,
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&hdr->daddr, dh->dccph_dport,
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&hdr->saddr, ntohs(dh->dccph_sport),
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inet6_iif(skb));
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if (!sk) {
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ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev),
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ICMP6_MIB_INERRORS);
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return;
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}
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if (sk->sk_state == DCCP_TIME_WAIT) {
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inet_twsk_put(inet_twsk(sk));
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return;
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}
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seq = dccp_hdr_seq(dh);
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if (sk->sk_state == DCCP_NEW_SYN_RECV)
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return dccp_req_err(sk, seq);
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bh_lock_sock(sk);
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if (sock_owned_by_user(sk))
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NET_INC_STATS_BH(net, LINUX_MIB_LOCKDROPPEDICMPS);
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if (sk->sk_state == DCCP_CLOSED)
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goto out;
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dp = dccp_sk(sk);
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if ((1 << sk->sk_state) & ~(DCCPF_REQUESTING | DCCPF_LISTEN) &&
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!between48(seq, dp->dccps_awl, dp->dccps_awh)) {
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NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS);
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goto out;
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}
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np = inet6_sk(sk);
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if (type == NDISC_REDIRECT) {
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struct dst_entry *dst = __sk_dst_check(sk, np->dst_cookie);
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if (dst)
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dst->ops->redirect(dst, sk, skb);
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goto out;
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}
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if (type == ICMPV6_PKT_TOOBIG) {
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struct dst_entry *dst = NULL;
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if (!ip6_sk_accept_pmtu(sk))
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goto out;
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if (sock_owned_by_user(sk))
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goto out;
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if ((1 << sk->sk_state) & (DCCPF_LISTEN | DCCPF_CLOSED))
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goto out;
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dst = inet6_csk_update_pmtu(sk, ntohl(info));
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if (!dst)
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goto out;
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if (inet_csk(sk)->icsk_pmtu_cookie > dst_mtu(dst))
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dccp_sync_mss(sk, dst_mtu(dst));
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goto out;
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}
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icmpv6_err_convert(type, code, &err);
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/* Might be for an request_sock */
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switch (sk->sk_state) {
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case DCCP_REQUESTING:
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case DCCP_RESPOND: /* Cannot happen.
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It can, it SYNs are crossed. --ANK */
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if (!sock_owned_by_user(sk)) {
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DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS);
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sk->sk_err = err;
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/*
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* Wake people up to see the error
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* (see connect in sock.c)
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*/
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sk->sk_error_report(sk);
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dccp_done(sk);
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} else
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sk->sk_err_soft = err;
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goto out;
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}
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if (!sock_owned_by_user(sk) && np->recverr) {
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sk->sk_err = err;
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sk->sk_error_report(sk);
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} else
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sk->sk_err_soft = err;
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out:
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bh_unlock_sock(sk);
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sock_put(sk);
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}
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static int dccp_v6_send_response(const struct sock *sk, struct request_sock *req)
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{
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struct inet_request_sock *ireq = inet_rsk(req);
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struct ipv6_pinfo *np = inet6_sk(sk);
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struct sk_buff *skb;
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struct in6_addr *final_p, final;
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struct flowi6 fl6;
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int err = -1;
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struct dst_entry *dst;
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memset(&fl6, 0, sizeof(fl6));
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fl6.flowi6_proto = IPPROTO_DCCP;
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fl6.daddr = ireq->ir_v6_rmt_addr;
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fl6.saddr = ireq->ir_v6_loc_addr;
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fl6.flowlabel = 0;
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fl6.flowi6_oif = ireq->ir_iif;
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fl6.fl6_dport = ireq->ir_rmt_port;
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fl6.fl6_sport = htons(ireq->ir_num);
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security_req_classify_flow(req, flowi6_to_flowi(&fl6));
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final_p = fl6_update_dst(&fl6, np->opt, &final);
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dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
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if (IS_ERR(dst)) {
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err = PTR_ERR(dst);
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dst = NULL;
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goto done;
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}
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skb = dccp_make_response(sk, dst, req);
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if (skb != NULL) {
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struct dccp_hdr *dh = dccp_hdr(skb);
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dh->dccph_checksum = dccp_v6_csum_finish(skb,
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&ireq->ir_v6_loc_addr,
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&ireq->ir_v6_rmt_addr);
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fl6.daddr = ireq->ir_v6_rmt_addr;
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err = ip6_xmit(sk, skb, &fl6, np->opt, np->tclass);
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err = net_xmit_eval(err);
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}
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done:
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dst_release(dst);
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return err;
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}
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static void dccp_v6_reqsk_destructor(struct request_sock *req)
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{
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dccp_feat_list_purge(&dccp_rsk(req)->dreq_featneg);
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kfree_skb(inet_rsk(req)->pktopts);
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}
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static void dccp_v6_ctl_send_reset(const struct sock *sk, struct sk_buff *rxskb)
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{
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const struct ipv6hdr *rxip6h;
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struct sk_buff *skb;
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struct flowi6 fl6;
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struct net *net = dev_net(skb_dst(rxskb)->dev);
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struct sock *ctl_sk = net->dccp.v6_ctl_sk;
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struct dst_entry *dst;
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if (dccp_hdr(rxskb)->dccph_type == DCCP_PKT_RESET)
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return;
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if (!ipv6_unicast_destination(rxskb))
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return;
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skb = dccp_ctl_make_reset(ctl_sk, rxskb);
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if (skb == NULL)
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return;
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rxip6h = ipv6_hdr(rxskb);
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dccp_hdr(skb)->dccph_checksum = dccp_v6_csum_finish(skb, &rxip6h->saddr,
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&rxip6h->daddr);
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memset(&fl6, 0, sizeof(fl6));
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fl6.daddr = rxip6h->saddr;
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fl6.saddr = rxip6h->daddr;
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fl6.flowi6_proto = IPPROTO_DCCP;
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fl6.flowi6_oif = inet6_iif(rxskb);
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fl6.fl6_dport = dccp_hdr(skb)->dccph_dport;
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fl6.fl6_sport = dccp_hdr(skb)->dccph_sport;
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security_skb_classify_flow(rxskb, flowi6_to_flowi(&fl6));
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/* sk = NULL, but it is safe for now. RST socket required. */
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dst = ip6_dst_lookup_flow(ctl_sk, &fl6, NULL);
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if (!IS_ERR(dst)) {
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skb_dst_set(skb, dst);
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ip6_xmit(ctl_sk, skb, &fl6, NULL, 0);
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DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS);
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DCCP_INC_STATS_BH(DCCP_MIB_OUTRSTS);
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return;
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}
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kfree_skb(skb);
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}
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static struct request_sock_ops dccp6_request_sock_ops = {
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.family = AF_INET6,
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.obj_size = sizeof(struct dccp6_request_sock),
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.rtx_syn_ack = dccp_v6_send_response,
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.send_ack = dccp_reqsk_send_ack,
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.destructor = dccp_v6_reqsk_destructor,
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.send_reset = dccp_v6_ctl_send_reset,
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.syn_ack_timeout = dccp_syn_ack_timeout,
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};
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static int dccp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
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{
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struct request_sock *req;
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struct dccp_request_sock *dreq;
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struct inet_request_sock *ireq;
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struct ipv6_pinfo *np = inet6_sk(sk);
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const __be32 service = dccp_hdr_request(skb)->dccph_req_service;
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struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
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if (skb->protocol == htons(ETH_P_IP))
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return dccp_v4_conn_request(sk, skb);
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if (!ipv6_unicast_destination(skb))
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return 0; /* discard, don't send a reset here */
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if (dccp_bad_service_code(sk, service)) {
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dcb->dccpd_reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE;
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goto drop;
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}
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/*
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* There are no SYN attacks on IPv6, yet...
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*/
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dcb->dccpd_reset_code = DCCP_RESET_CODE_TOO_BUSY;
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if (inet_csk_reqsk_queue_is_full(sk))
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goto drop;
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if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1)
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goto drop;
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req = inet_reqsk_alloc(&dccp6_request_sock_ops, sk);
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if (req == NULL)
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goto drop;
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if (dccp_reqsk_init(req, dccp_sk(sk), skb))
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goto drop_and_free;
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dreq = dccp_rsk(req);
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if (dccp_parse_options(sk, dreq, skb))
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goto drop_and_free;
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if (security_inet_conn_request(sk, skb, req))
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goto drop_and_free;
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ireq = inet_rsk(req);
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ireq->ir_v6_rmt_addr = ipv6_hdr(skb)->saddr;
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ireq->ir_v6_loc_addr = ipv6_hdr(skb)->daddr;
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ireq->ireq_family = AF_INET6;
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if (ipv6_opt_accepted(sk, skb, IP6CB(skb)) ||
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np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo ||
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np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) {
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atomic_inc(&skb->users);
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ireq->pktopts = skb;
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}
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ireq->ir_iif = sk->sk_bound_dev_if;
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|
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/* So that link locals have meaning */
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if (!sk->sk_bound_dev_if &&
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ipv6_addr_type(&ireq->ir_v6_rmt_addr) & IPV6_ADDR_LINKLOCAL)
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ireq->ir_iif = inet6_iif(skb);
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|
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/*
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* Step 3: Process LISTEN state
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*
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* Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie
|
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*
|
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* Setting S.SWL/S.SWH to is deferred to dccp_create_openreq_child().
|
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*/
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dreq->dreq_isr = dcb->dccpd_seq;
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dreq->dreq_gsr = dreq->dreq_isr;
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dreq->dreq_iss = dccp_v6_init_sequence(skb);
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dreq->dreq_gss = dreq->dreq_iss;
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dreq->dreq_service = service;
|
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|
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if (dccp_v6_send_response(sk, req))
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goto drop_and_free;
|
|
|
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inet_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT);
|
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return 0;
|
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|
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drop_and_free:
|
|
reqsk_free(req);
|
|
drop:
|
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DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS);
|
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return -1;
|
|
}
|
|
|
|
static struct sock *dccp_v6_request_recv_sock(const struct sock *sk,
|
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struct sk_buff *skb,
|
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struct request_sock *req,
|
|
struct dst_entry *dst)
|
|
{
|
|
struct inet_request_sock *ireq = inet_rsk(req);
|
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struct ipv6_pinfo *newnp;
|
|
const struct ipv6_pinfo *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));
|
|
|
|
newnp->saddr = newsk->sk_v6_rcv_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) {
|
|
struct flowi6 fl6;
|
|
|
|
dst = inet6_csk_route_req(sk, &fl6, req, IPPROTO_DCCP);
|
|
if (!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;
|
|
}
|
|
__inet_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 (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,
|
|
inet6_iif(skb));
|
|
/*
|
|
* 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;
|
|
}
|
|
|
|
if (sk->sk_state == DCCP_NEW_SYN_RECV) {
|
|
struct request_sock *req = inet_reqsk(sk);
|
|
struct sock *nsk = NULL;
|
|
|
|
sk = req->rsk_listener;
|
|
if (sk->sk_state == DCCP_LISTEN)
|
|
nsk = dccp_check_req(sk, skb, req);
|
|
if (!nsk) {
|
|
reqsk_put(req);
|
|
goto discard_it;
|
|
}
|
|
if (nsk == sk) {
|
|
sock_hold(sk);
|
|
reqsk_put(req);
|
|
} else if (dccp_child_process(sk, nsk, skb)) {
|
|
dccp_v6_ctl_send_reset(sk, skb);
|
|
goto discard_it;
|
|
} else {
|
|
return 0;
|
|
}
|
|
}
|
|
/*
|
|
* 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;
|
|
}
|
|
np->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);
|
|
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 = inet_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");
|