Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 1 | /* |
| 2 | * net/dccp/ipv4.c |
| 3 | * |
| 4 | * An implementation of the DCCP protocol |
| 5 | * Arnaldo Carvalho de Melo <acme@conectiva.com.br> |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or |
| 8 | * modify it under the terms of the GNU General Public License |
| 9 | * as published by the Free Software Foundation; either version |
| 10 | * 2 of the License, or (at your option) any later version. |
| 11 | */ |
| 12 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 13 | #include <linux/dccp.h> |
| 14 | #include <linux/icmp.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 15 | #include <linux/slab.h> |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 16 | #include <linux/module.h> |
| 17 | #include <linux/skbuff.h> |
| 18 | #include <linux/random.h> |
| 19 | |
| 20 | #include <net/icmp.h> |
Arnaldo Carvalho de Melo | b61fafc | 2006-03-20 21:25:11 -0800 | [diff] [blame] | 21 | #include <net/inet_common.h> |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 22 | #include <net/inet_hashtables.h> |
Arnaldo Carvalho de Melo | 14c8502 | 2005-12-27 02:43:12 -0200 | [diff] [blame] | 23 | #include <net/inet_sock.h> |
Arnaldo Carvalho de Melo | b61fafc | 2006-03-20 21:25:11 -0800 | [diff] [blame] | 24 | #include <net/protocol.h> |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 25 | #include <net/sock.h> |
Arnaldo Carvalho de Melo | 6d6ee43 | 2005-12-13 23:25:19 -0800 | [diff] [blame] | 26 | #include <net/timewait_sock.h> |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 27 | #include <net/tcp_states.h> |
| 28 | #include <net/xfrm.h> |
David S. Miller | 6e5714e | 2011-08-03 20:50:44 -0700 | [diff] [blame] | 29 | #include <net/secure_seq.h> |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 30 | |
Arnaldo Carvalho de Melo | ae31c33 | 2005-09-18 00:17:51 -0700 | [diff] [blame] | 31 | #include "ackvec.h" |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 32 | #include "ccid.h" |
| 33 | #include "dccp.h" |
Andrea Bittau | afe0025 | 2006-03-20 17:43:56 -0800 | [diff] [blame] | 34 | #include "feat.h" |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 35 | |
Arnaldo Carvalho de Melo | 7247887 | 2006-03-20 22:00:37 -0800 | [diff] [blame] | 36 | /* |
Pavel Emelyanov | 13f51d8 | 2008-04-14 02:38:45 -0700 | [diff] [blame] | 37 | * The per-net dccp.v4_ctl_sk socket is used for responding to |
Arnaldo Carvalho de Melo | 7247887 | 2006-03-20 22:00:37 -0800 | [diff] [blame] | 38 | * the Out-of-the-blue (OOTB) packets. A control sock will be created |
| 39 | * for this socket at the initialization time. |
| 40 | */ |
Arnaldo Carvalho de Melo | 7247887 | 2006-03-20 22:00:37 -0800 | [diff] [blame] | 41 | |
Arnaldo Carvalho de Melo | f21e68c | 2005-12-13 23:24:16 -0800 | [diff] [blame] | 42 | int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 43 | { |
David S. Miller | 2d7192d | 2011-04-26 13:28:44 -0700 | [diff] [blame] | 44 | const struct sockaddr_in *usin = (struct sockaddr_in *)uaddr; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 45 | struct inet_sock *inet = inet_sk(sk); |
| 46 | struct dccp_sock *dp = dccp_sk(sk); |
David S. Miller | dca8b08 | 2011-02-24 13:38:12 -0800 | [diff] [blame] | 47 | __be16 orig_sport, orig_dport; |
Al Viro | bada8ad | 2006-09-26 21:27:15 -0700 | [diff] [blame] | 48 | __be32 daddr, nexthop; |
David S. Miller | 2c42758 | 2011-05-06 16:10:41 -0700 | [diff] [blame] | 49 | struct flowi4 *fl4; |
David S. Miller | 2d7192d | 2011-04-26 13:28:44 -0700 | [diff] [blame] | 50 | struct rtable *rt; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 51 | int err; |
Eric Dumazet | f6d8bd0 | 2011-04-21 09:45:37 +0000 | [diff] [blame] | 52 | struct ip_options_rcu *inet_opt; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 53 | |
| 54 | dp->dccps_role = DCCP_ROLE_CLIENT; |
| 55 | |
| 56 | if (addr_len < sizeof(struct sockaddr_in)) |
| 57 | return -EINVAL; |
| 58 | |
| 59 | if (usin->sin_family != AF_INET) |
| 60 | return -EAFNOSUPPORT; |
| 61 | |
| 62 | nexthop = daddr = usin->sin_addr.s_addr; |
Eric Dumazet | f6d8bd0 | 2011-04-21 09:45:37 +0000 | [diff] [blame] | 63 | |
| 64 | inet_opt = rcu_dereference_protected(inet->inet_opt, |
| 65 | sock_owned_by_user(sk)); |
| 66 | if (inet_opt != NULL && inet_opt->opt.srr) { |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 67 | if (daddr == 0) |
| 68 | return -EINVAL; |
Eric Dumazet | f6d8bd0 | 2011-04-21 09:45:37 +0000 | [diff] [blame] | 69 | nexthop = inet_opt->opt.faddr; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 70 | } |
| 71 | |
David S. Miller | dca8b08 | 2011-02-24 13:38:12 -0800 | [diff] [blame] | 72 | orig_sport = inet->inet_sport; |
| 73 | orig_dport = usin->sin_port; |
David S. Miller | 2c42758 | 2011-05-06 16:10:41 -0700 | [diff] [blame] | 74 | fl4 = &inet->cork.fl.u.ip4; |
| 75 | rt = ip_route_connect(fl4, nexthop, inet->inet_saddr, |
David S. Miller | b23dd4f | 2011-03-02 14:31:35 -0800 | [diff] [blame] | 76 | RT_CONN_FLAGS(sk), sk->sk_bound_dev_if, |
| 77 | IPPROTO_DCCP, |
| 78 | orig_sport, orig_dport, sk, true); |
| 79 | if (IS_ERR(rt)) |
| 80 | return PTR_ERR(rt); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 81 | |
| 82 | if (rt->rt_flags & (RTCF_MULTICAST | RTCF_BROADCAST)) { |
| 83 | ip_rt_put(rt); |
| 84 | return -ENETUNREACH; |
| 85 | } |
| 86 | |
Eric Dumazet | f6d8bd0 | 2011-04-21 09:45:37 +0000 | [diff] [blame] | 87 | if (inet_opt == NULL || !inet_opt->opt.srr) |
David S. Miller | 2c42758 | 2011-05-06 16:10:41 -0700 | [diff] [blame] | 88 | daddr = fl4->daddr; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 89 | |
Eric Dumazet | c720c7e | 2009-10-15 06:30:45 +0000 | [diff] [blame] | 90 | if (inet->inet_saddr == 0) |
David S. Miller | 2c42758 | 2011-05-06 16:10:41 -0700 | [diff] [blame] | 91 | inet->inet_saddr = fl4->saddr; |
Eric Dumazet | c720c7e | 2009-10-15 06:30:45 +0000 | [diff] [blame] | 92 | inet->inet_rcv_saddr = inet->inet_saddr; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 93 | |
Eric Dumazet | c720c7e | 2009-10-15 06:30:45 +0000 | [diff] [blame] | 94 | inet->inet_dport = usin->sin_port; |
| 95 | inet->inet_daddr = daddr; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 96 | |
Arnaldo Carvalho de Melo | d83d846 | 2005-12-13 23:26:10 -0800 | [diff] [blame] | 97 | inet_csk(sk)->icsk_ext_hdr_len = 0; |
Eric Dumazet | f6d8bd0 | 2011-04-21 09:45:37 +0000 | [diff] [blame] | 98 | if (inet_opt) |
| 99 | inet_csk(sk)->icsk_ext_hdr_len = inet_opt->opt.optlen; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 100 | /* |
| 101 | * Socket identity is still unknown (sport may be zero). |
| 102 | * However we set state to DCCP_REQUESTING and not releasing socket |
| 103 | * lock select source port, enter ourselves into the hash tables and |
| 104 | * complete initialization after this. |
| 105 | */ |
| 106 | dccp_set_state(sk, DCCP_REQUESTING); |
Arnaldo Carvalho de Melo | a7f5e7f | 2005-12-13 23:25:31 -0800 | [diff] [blame] | 107 | err = inet_hash_connect(&dccp_death_row, sk); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 108 | if (err != 0) |
| 109 | goto failure; |
| 110 | |
David S. Miller | 2c42758 | 2011-05-06 16:10:41 -0700 | [diff] [blame] | 111 | rt = ip_route_newports(fl4, rt, orig_sport, orig_dport, |
David S. Miller | b23dd4f | 2011-03-02 14:31:35 -0800 | [diff] [blame] | 112 | inet->inet_sport, inet->inet_dport, sk); |
| 113 | if (IS_ERR(rt)) { |
RongQing.Li | 525c646 | 2011-11-21 16:45:26 -0500 | [diff] [blame] | 114 | err = PTR_ERR(rt); |
David S. Miller | b23dd4f | 2011-03-02 14:31:35 -0800 | [diff] [blame] | 115 | rt = NULL; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 116 | goto failure; |
David S. Miller | b23dd4f | 2011-03-02 14:31:35 -0800 | [diff] [blame] | 117 | } |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 118 | /* OK, now commit destination to socket. */ |
Changli Gao | d8d1f30 | 2010-06-10 23:31:35 -0700 | [diff] [blame] | 119 | sk_setup_caps(sk, &rt->dst); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 120 | |
Eric Dumazet | c720c7e | 2009-10-15 06:30:45 +0000 | [diff] [blame] | 121 | dp->dccps_iss = secure_dccp_sequence_number(inet->inet_saddr, |
| 122 | inet->inet_daddr, |
| 123 | inet->inet_sport, |
| 124 | inet->inet_dport); |
| 125 | inet->inet_id = dp->dccps_iss ^ jiffies; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 126 | |
| 127 | err = dccp_connect(sk); |
| 128 | rt = NULL; |
| 129 | if (err != 0) |
| 130 | goto failure; |
| 131 | out: |
| 132 | return err; |
| 133 | failure: |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 134 | /* |
| 135 | * This unhashes the socket and releases the local port, if necessary. |
| 136 | */ |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 137 | dccp_set_state(sk, DCCP_CLOSED); |
| 138 | ip_rt_put(rt); |
| 139 | sk->sk_route_caps = 0; |
Eric Dumazet | c720c7e | 2009-10-15 06:30:45 +0000 | [diff] [blame] | 140 | inet->inet_dport = 0; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 141 | goto out; |
| 142 | } |
| 143 | |
Arnaldo Carvalho de Melo | f21e68c | 2005-12-13 23:24:16 -0800 | [diff] [blame] | 144 | EXPORT_SYMBOL_GPL(dccp_v4_connect); |
| 145 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 146 | /* |
| 147 | * This routine does path mtu discovery as defined in RFC1191. |
| 148 | */ |
| 149 | static inline void dccp_do_pmtu_discovery(struct sock *sk, |
| 150 | const struct iphdr *iph, |
| 151 | u32 mtu) |
| 152 | { |
| 153 | struct dst_entry *dst; |
| 154 | const struct inet_sock *inet = inet_sk(sk); |
| 155 | const struct dccp_sock *dp = dccp_sk(sk); |
| 156 | |
| 157 | /* We are not interested in DCCP_LISTEN and request_socks (RESPONSEs |
| 158 | * send out by Linux are always < 576bytes so they should go through |
| 159 | * unfragmented). |
| 160 | */ |
| 161 | if (sk->sk_state == DCCP_LISTEN) |
| 162 | return; |
| 163 | |
| 164 | /* We don't check in the destentry if pmtu discovery is forbidden |
| 165 | * on this route. We just assume that no packet_to_big packets |
| 166 | * are send back when pmtu discovery is not active. |
YOSHIFUJI Hideaki | c9eaf17 | 2007-02-09 23:24:38 +0900 | [diff] [blame] | 167 | * There is a small race when the user changes this flag in the |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 168 | * route, but I think that's acceptable. |
| 169 | */ |
| 170 | if ((dst = __sk_dst_check(sk, 0)) == NULL) |
| 171 | return; |
| 172 | |
| 173 | dst->ops->update_pmtu(dst, mtu); |
| 174 | |
| 175 | /* Something is about to be wrong... Remember soft error |
| 176 | * for the case, if this connection will not able to recover. |
| 177 | */ |
| 178 | if (mtu < dst_mtu(dst) && ip_dont_fragment(sk, dst)) |
| 179 | sk->sk_err_soft = EMSGSIZE; |
| 180 | |
| 181 | mtu = dst_mtu(dst); |
| 182 | |
| 183 | if (inet->pmtudisc != IP_PMTUDISC_DONT && |
Arnaldo Carvalho de Melo | d83d846 | 2005-12-13 23:26:10 -0800 | [diff] [blame] | 184 | inet_csk(sk)->icsk_pmtu_cookie > mtu) { |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 185 | dccp_sync_mss(sk, mtu); |
| 186 | |
| 187 | /* |
Gerrit Renker | 0e64e94 | 2006-10-24 16:17:51 -0700 | [diff] [blame] | 188 | * From RFC 4340, sec. 14.1: |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 189 | * |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 190 | * DCCP-Sync packets are the best choice for upward |
| 191 | * probing, since DCCP-Sync probes do not risk application |
| 192 | * data loss. |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 193 | */ |
Arnaldo Carvalho de Melo | e92ae93 | 2005-08-17 03:10:59 -0300 | [diff] [blame] | 194 | dccp_send_sync(sk, dp->dccps_gsr, DCCP_PKT_SYNC); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 195 | } /* else let the usual retransmit timer handle it */ |
| 196 | } |
| 197 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 198 | /* |
| 199 | * This routine is called by the ICMP module when it gets some sort of error |
| 200 | * condition. If err < 0 then the socket should be closed and the error |
| 201 | * returned to the user. If err > 0 it's just the icmp type << 8 | icmp code. |
| 202 | * After adjustment header points to the first 8 bytes of the tcp header. We |
| 203 | * need to find the appropriate port. |
| 204 | * |
| 205 | * The locking strategy used here is very "optimistic". When someone else |
| 206 | * accesses the socket the ICMP is just dropped and for some paths there is no |
| 207 | * check at all. A more general error queue to queue errors for later handling |
| 208 | * is probably better. |
| 209 | */ |
Arnaldo Carvalho de Melo | b61fafc | 2006-03-20 21:25:11 -0800 | [diff] [blame] | 210 | static void dccp_v4_err(struct sk_buff *skb, u32 info) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 211 | { |
| 212 | const struct iphdr *iph = (struct iphdr *)skb->data; |
Wei Yongjun | 18e1d83 | 2008-07-26 11:59:10 +0100 | [diff] [blame] | 213 | const u8 offset = iph->ihl << 2; |
| 214 | const struct dccp_hdr *dh = (struct dccp_hdr *)(skb->data + offset); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 215 | struct dccp_sock *dp; |
| 216 | struct inet_sock *inet; |
Arnaldo Carvalho de Melo | 88c7664 | 2007-03-13 14:43:18 -0300 | [diff] [blame] | 217 | const int type = icmp_hdr(skb)->type; |
| 218 | const int code = icmp_hdr(skb)->code; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 219 | struct sock *sk; |
| 220 | __u64 seq; |
| 221 | int err; |
Pavel Emelyanov | fd54d71 | 2008-07-14 23:01:40 -0700 | [diff] [blame] | 222 | struct net *net = dev_net(skb->dev); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 223 | |
Wei Yongjun | 18e1d83 | 2008-07-26 11:59:10 +0100 | [diff] [blame] | 224 | if (skb->len < offset + sizeof(*dh) || |
| 225 | skb->len < offset + __dccp_basic_hdr_len(dh)) { |
Pavel Emelyanov | dcfc23c | 2008-07-14 23:03:00 -0700 | [diff] [blame] | 226 | ICMP_INC_STATS_BH(net, ICMP_MIB_INERRORS); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 227 | return; |
| 228 | } |
| 229 | |
Pavel Emelyanov | fd54d71 | 2008-07-14 23:01:40 -0700 | [diff] [blame] | 230 | sk = inet_lookup(net, &dccp_hashinfo, |
Pavel Emelyanov | b9901a8 | 2008-04-13 22:30:43 -0700 | [diff] [blame] | 231 | iph->daddr, dh->dccph_dport, |
| 232 | iph->saddr, dh->dccph_sport, inet_iif(skb)); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 233 | if (sk == NULL) { |
Pavel Emelyanov | dcfc23c | 2008-07-14 23:03:00 -0700 | [diff] [blame] | 234 | ICMP_INC_STATS_BH(net, ICMP_MIB_INERRORS); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 235 | return; |
| 236 | } |
| 237 | |
| 238 | if (sk->sk_state == DCCP_TIME_WAIT) { |
YOSHIFUJI Hideaki | 9469c7b | 2006-10-10 19:41:46 -0700 | [diff] [blame] | 239 | inet_twsk_put(inet_twsk(sk)); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 240 | return; |
| 241 | } |
| 242 | |
| 243 | bh_lock_sock(sk); |
| 244 | /* If too many ICMPs get dropped on busy |
| 245 | * servers this needs to be solved differently. |
| 246 | */ |
| 247 | if (sock_owned_by_user(sk)) |
Pavel Emelyanov | de0744a | 2008-07-16 20:31:16 -0700 | [diff] [blame] | 248 | NET_INC_STATS_BH(net, LINUX_MIB_LOCKDROPPEDICMPS); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 249 | |
| 250 | if (sk->sk_state == DCCP_CLOSED) |
| 251 | goto out; |
| 252 | |
| 253 | dp = dccp_sk(sk); |
Gerrit Renker | fde2010 | 2007-10-24 10:12:09 -0200 | [diff] [blame] | 254 | seq = dccp_hdr_seq(dh); |
Gerrit Renker | 1238d08 | 2007-10-24 10:18:06 -0200 | [diff] [blame] | 255 | if ((1 << sk->sk_state) & ~(DCCPF_REQUESTING | DCCPF_LISTEN) && |
Wei Yongjun | d68f086 | 2008-07-26 11:59:10 +0100 | [diff] [blame] | 256 | !between48(seq, dp->dccps_awl, dp->dccps_awh)) { |
Pavel Emelyanov | de0744a | 2008-07-16 20:31:16 -0700 | [diff] [blame] | 257 | NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 258 | goto out; |
| 259 | } |
| 260 | |
| 261 | switch (type) { |
| 262 | case ICMP_SOURCE_QUENCH: |
| 263 | /* Just silently ignore these. */ |
| 264 | goto out; |
| 265 | case ICMP_PARAMETERPROB: |
| 266 | err = EPROTO; |
| 267 | break; |
| 268 | case ICMP_DEST_UNREACH: |
| 269 | if (code > NR_ICMP_UNREACH) |
| 270 | goto out; |
| 271 | |
| 272 | if (code == ICMP_FRAG_NEEDED) { /* PMTU discovery (RFC1191) */ |
| 273 | if (!sock_owned_by_user(sk)) |
| 274 | dccp_do_pmtu_discovery(sk, iph, info); |
| 275 | goto out; |
| 276 | } |
| 277 | |
| 278 | err = icmp_err_convert[code].errno; |
| 279 | break; |
| 280 | case ICMP_TIME_EXCEEDED: |
| 281 | err = EHOSTUNREACH; |
| 282 | break; |
| 283 | default: |
| 284 | goto out; |
| 285 | } |
| 286 | |
| 287 | switch (sk->sk_state) { |
| 288 | struct request_sock *req , **prev; |
| 289 | case DCCP_LISTEN: |
| 290 | if (sock_owned_by_user(sk)) |
| 291 | goto out; |
| 292 | req = inet_csk_search_req(sk, &prev, dh->dccph_dport, |
| 293 | iph->daddr, iph->saddr); |
| 294 | if (!req) |
| 295 | goto out; |
| 296 | |
| 297 | /* |
| 298 | * ICMPs are not backlogged, hence we cannot get an established |
| 299 | * socket here. |
| 300 | */ |
Ilpo Järvinen | 547b792 | 2008-07-25 21:43:18 -0700 | [diff] [blame] | 301 | WARN_ON(req->sk); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 302 | |
Samuel Jero | f541fb7 | 2012-02-26 18:22:02 -0700 | [diff] [blame] | 303 | if (!between48(seq, dccp_rsk(req)->dreq_iss, |
| 304 | dccp_rsk(req)->dreq_gss)) { |
Pavel Emelyanov | de0744a | 2008-07-16 20:31:16 -0700 | [diff] [blame] | 305 | NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 306 | goto out; |
| 307 | } |
| 308 | /* |
| 309 | * Still in RESPOND, just remove it silently. |
| 310 | * There is no good way to pass the error to the newly |
| 311 | * created socket, and POSIX does not want network |
| 312 | * errors returned from accept(). |
| 313 | */ |
| 314 | inet_csk_reqsk_queue_drop(sk, req, prev); |
| 315 | goto out; |
| 316 | |
| 317 | case DCCP_REQUESTING: |
| 318 | case DCCP_RESPOND: |
| 319 | if (!sock_owned_by_user(sk)) { |
| 320 | DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS); |
| 321 | sk->sk_err = err; |
| 322 | |
| 323 | sk->sk_error_report(sk); |
| 324 | |
| 325 | dccp_done(sk); |
| 326 | } else |
| 327 | sk->sk_err_soft = err; |
| 328 | goto out; |
| 329 | } |
| 330 | |
| 331 | /* If we've already connected we will keep trying |
| 332 | * until we time out, or the user gives up. |
| 333 | * |
| 334 | * rfc1122 4.2.3.9 allows to consider as hard errors |
| 335 | * only PROTO_UNREACH and PORT_UNREACH (well, FRAG_FAILED too, |
| 336 | * but it is obsoleted by pmtu discovery). |
| 337 | * |
| 338 | * Note, that in modern internet, where routing is unreliable |
| 339 | * and in each dark corner broken firewalls sit, sending random |
| 340 | * errors ordered by their masters even this two messages finally lose |
| 341 | * their original sense (even Linux sends invalid PORT_UNREACHs) |
| 342 | * |
| 343 | * Now we are in compliance with RFCs. |
| 344 | * --ANK (980905) |
| 345 | */ |
| 346 | |
| 347 | inet = inet_sk(sk); |
| 348 | if (!sock_owned_by_user(sk) && inet->recverr) { |
| 349 | sk->sk_err = err; |
| 350 | sk->sk_error_report(sk); |
| 351 | } else /* Only an error on timeout */ |
| 352 | sk->sk_err_soft = err; |
| 353 | out: |
| 354 | bh_unlock_sock(sk); |
| 355 | sock_put(sk); |
| 356 | } |
| 357 | |
Al Viro | 2bda285 | 2006-11-14 21:28:51 -0800 | [diff] [blame] | 358 | static inline __sum16 dccp_v4_csum_finish(struct sk_buff *skb, |
Gerrit Renker | 6f4e5ff | 2006-11-10 17:43:06 -0200 | [diff] [blame] | 359 | __be32 src, __be32 dst) |
| 360 | { |
| 361 | return csum_tcpudp_magic(src, dst, skb->len, IPPROTO_DCCP, skb->csum); |
| 362 | } |
| 363 | |
Herbert Xu | bb29624 | 2010-04-11 02:15:55 +0000 | [diff] [blame] | 364 | void dccp_v4_send_check(struct sock *sk, struct sk_buff *skb) |
Arnaldo Carvalho de Melo | 57cca05 | 2005-12-13 23:16:16 -0800 | [diff] [blame] | 365 | { |
| 366 | const struct inet_sock *inet = inet_sk(sk); |
| 367 | struct dccp_hdr *dh = dccp_hdr(skb); |
| 368 | |
Gerrit Renker | 6f4e5ff | 2006-11-10 17:43:06 -0200 | [diff] [blame] | 369 | dccp_csum_outgoing(skb); |
Eric Dumazet | c720c7e | 2009-10-15 06:30:45 +0000 | [diff] [blame] | 370 | dh->dccph_checksum = dccp_v4_csum_finish(skb, |
| 371 | inet->inet_saddr, |
| 372 | inet->inet_daddr); |
Arnaldo Carvalho de Melo | 57cca05 | 2005-12-13 23:16:16 -0800 | [diff] [blame] | 373 | } |
| 374 | |
Arnaldo Carvalho de Melo | f21e68c | 2005-12-13 23:24:16 -0800 | [diff] [blame] | 375 | EXPORT_SYMBOL_GPL(dccp_v4_send_check); |
| 376 | |
Gerrit Renker | 865e902 | 2006-11-13 13:31:50 -0200 | [diff] [blame] | 377 | static inline u64 dccp_v4_init_sequence(const struct sk_buff *skb) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 378 | { |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 379 | return secure_dccp_sequence_number(ip_hdr(skb)->daddr, |
| 380 | ip_hdr(skb)->saddr, |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 381 | dccp_hdr(skb)->dccph_dport, |
| 382 | dccp_hdr(skb)->dccph_sport); |
| 383 | } |
| 384 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 385 | /* |
| 386 | * The three way handshake has completed - we got a valid ACK or DATAACK - |
| 387 | * now create the new socket. |
| 388 | * |
| 389 | * This is the equivalent of TCP's tcp_v4_syn_recv_sock |
| 390 | */ |
| 391 | struct sock *dccp_v4_request_recv_sock(struct sock *sk, struct sk_buff *skb, |
| 392 | struct request_sock *req, |
| 393 | struct dst_entry *dst) |
| 394 | { |
| 395 | struct inet_request_sock *ireq; |
| 396 | struct inet_sock *newinet; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 397 | struct sock *newsk; |
| 398 | |
| 399 | if (sk_acceptq_is_full(sk)) |
| 400 | goto exit_overflow; |
| 401 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 402 | newsk = dccp_create_openreq_child(sk, req, skb); |
| 403 | if (newsk == NULL) |
Balazs Scheidler | 093d282 | 2010-10-21 13:06:43 +0200 | [diff] [blame] | 404 | goto exit_nonewsk; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 405 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 406 | newinet = inet_sk(newsk); |
| 407 | ireq = inet_rsk(req); |
Eric Dumazet | c720c7e | 2009-10-15 06:30:45 +0000 | [diff] [blame] | 408 | newinet->inet_daddr = ireq->rmt_addr; |
| 409 | newinet->inet_rcv_saddr = ireq->loc_addr; |
| 410 | newinet->inet_saddr = ireq->loc_addr; |
Eric Dumazet | f6d8bd0 | 2011-04-21 09:45:37 +0000 | [diff] [blame] | 411 | newinet->inet_opt = ireq->opt; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 412 | ireq->opt = NULL; |
| 413 | newinet->mc_index = inet_iif(skb); |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 414 | newinet->mc_ttl = ip_hdr(skb)->ttl; |
Eric Dumazet | c720c7e | 2009-10-15 06:30:45 +0000 | [diff] [blame] | 415 | newinet->inet_id = jiffies; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 416 | |
David S. Miller | 0e73441 | 2011-05-08 15:28:03 -0700 | [diff] [blame] | 417 | if (dst == NULL && (dst = inet_csk_route_child_sock(sk, newsk, req)) == NULL) |
| 418 | goto put_and_exit; |
| 419 | |
| 420 | sk_setup_caps(newsk, dst); |
| 421 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 422 | dccp_sync_mss(newsk, dst_mtu(dst)); |
| 423 | |
David S. Miller | 0e73441 | 2011-05-08 15:28:03 -0700 | [diff] [blame] | 424 | if (__inet_inherit_port(sk, newsk) < 0) |
| 425 | goto put_and_exit; |
Eric Dumazet | 9327f70 | 2009-12-04 03:46:54 +0000 | [diff] [blame] | 426 | __inet_hash_nolisten(newsk, NULL); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 427 | |
| 428 | return newsk; |
| 429 | |
| 430 | exit_overflow: |
Pavel Emelyanov | de0744a | 2008-07-16 20:31:16 -0700 | [diff] [blame] | 431 | NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS); |
Balazs Scheidler | 093d282 | 2010-10-21 13:06:43 +0200 | [diff] [blame] | 432 | exit_nonewsk: |
| 433 | dst_release(dst); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 434 | exit: |
Pavel Emelyanov | de0744a | 2008-07-16 20:31:16 -0700 | [diff] [blame] | 435 | NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 436 | return NULL; |
David S. Miller | 0e73441 | 2011-05-08 15:28:03 -0700 | [diff] [blame] | 437 | put_and_exit: |
Eric Dumazet | 918eb39 | 2011-11-02 12:42:56 +0000 | [diff] [blame] | 438 | bh_unlock_sock(newsk); |
David S. Miller | 0e73441 | 2011-05-08 15:28:03 -0700 | [diff] [blame] | 439 | sock_put(newsk); |
| 440 | goto exit; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 441 | } |
| 442 | |
Arnaldo Carvalho de Melo | f21e68c | 2005-12-13 23:24:16 -0800 | [diff] [blame] | 443 | EXPORT_SYMBOL_GPL(dccp_v4_request_recv_sock); |
| 444 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 445 | static struct sock *dccp_v4_hnd_req(struct sock *sk, struct sk_buff *skb) |
| 446 | { |
| 447 | const struct dccp_hdr *dh = dccp_hdr(skb); |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 448 | const struct iphdr *iph = ip_hdr(skb); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 449 | struct sock *nsk; |
| 450 | struct request_sock **prev; |
| 451 | /* Find possible connection requests. */ |
| 452 | struct request_sock *req = inet_csk_search_req(sk, &prev, |
| 453 | dh->dccph_sport, |
| 454 | iph->saddr, iph->daddr); |
| 455 | if (req != NULL) |
| 456 | return dccp_check_req(sk, skb, req, prev); |
| 457 | |
Pavel Emelyanov | b9901a8 | 2008-04-13 22:30:43 -0700 | [diff] [blame] | 458 | nsk = inet_lookup_established(sock_net(sk), &dccp_hashinfo, |
Herbert Xu | 8f49106 | 2006-08-09 15:47:12 -0700 | [diff] [blame] | 459 | iph->saddr, dh->dccph_sport, |
| 460 | iph->daddr, dh->dccph_dport, |
| 461 | inet_iif(skb)); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 462 | if (nsk != NULL) { |
| 463 | if (nsk->sk_state != DCCP_TIME_WAIT) { |
| 464 | bh_lock_sock(nsk); |
| 465 | return nsk; |
| 466 | } |
YOSHIFUJI Hideaki | 9469c7b | 2006-10-10 19:41:46 -0700 | [diff] [blame] | 467 | inet_twsk_put(inet_twsk(nsk)); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 468 | return NULL; |
| 469 | } |
| 470 | |
| 471 | return sk; |
| 472 | } |
| 473 | |
Pavel Emelyanov | f548739 | 2008-04-13 22:30:19 -0700 | [diff] [blame] | 474 | static struct dst_entry* dccp_v4_route_skb(struct net *net, struct sock *sk, |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 475 | struct sk_buff *skb) |
| 476 | { |
| 477 | struct rtable *rt; |
David S. Miller | 898f735 | 2011-12-01 13:28:34 -0500 | [diff] [blame] | 478 | const struct iphdr *iph = ip_hdr(skb); |
David S. Miller | 9d6ec93 | 2011-03-12 01:12:47 -0500 | [diff] [blame] | 479 | struct flowi4 fl4 = { |
| 480 | .flowi4_oif = skb_rtable(skb)->rt_iif, |
David S. Miller | 898f735 | 2011-12-01 13:28:34 -0500 | [diff] [blame] | 481 | .daddr = iph->saddr, |
| 482 | .saddr = iph->daddr, |
David S. Miller | 9d6ec93 | 2011-03-12 01:12:47 -0500 | [diff] [blame] | 483 | .flowi4_tos = RT_CONN_FLAGS(sk), |
| 484 | .flowi4_proto = sk->sk_protocol, |
David S. Miller | 9cce96d | 2011-03-12 03:00:33 -0500 | [diff] [blame] | 485 | .fl4_sport = dccp_hdr(skb)->dccph_dport, |
| 486 | .fl4_dport = dccp_hdr(skb)->dccph_sport, |
David S. Miller | 1d28f42 | 2011-03-12 00:29:39 -0500 | [diff] [blame] | 487 | }; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 488 | |
David S. Miller | 9d6ec93 | 2011-03-12 01:12:47 -0500 | [diff] [blame] | 489 | security_skb_classify_flow(skb, flowi4_to_flowi(&fl4)); |
| 490 | rt = ip_route_output_flow(net, &fl4, sk); |
David S. Miller | b23dd4f | 2011-03-02 14:31:35 -0800 | [diff] [blame] | 491 | if (IS_ERR(rt)) { |
Pavel Emelyanov | 7c73a6f | 2008-07-16 20:20:11 -0700 | [diff] [blame] | 492 | IP_INC_STATS_BH(net, IPSTATS_MIB_OUTNOROUTES); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 493 | return NULL; |
| 494 | } |
| 495 | |
Changli Gao | d8d1f30 | 2010-06-10 23:31:35 -0700 | [diff] [blame] | 496 | return &rt->dst; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 497 | } |
| 498 | |
William Allen Simpson | e6b4d11 | 2009-12-02 18:07:39 +0000 | [diff] [blame] | 499 | static int dccp_v4_send_response(struct sock *sk, struct request_sock *req, |
| 500 | struct request_values *rv_unused) |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 501 | { |
| 502 | int err = -1; |
| 503 | struct sk_buff *skb; |
Denis V. Lunev | fd80eb9 | 2008-02-29 11:43:03 -0800 | [diff] [blame] | 504 | struct dst_entry *dst; |
David S. Miller | 6bd023f | 2011-05-18 18:32:03 -0400 | [diff] [blame] | 505 | struct flowi4 fl4; |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 506 | |
David S. Miller | 6bd023f | 2011-05-18 18:32:03 -0400 | [diff] [blame] | 507 | dst = inet_csk_route_req(sk, &fl4, req); |
Denis V. Lunev | fd80eb9 | 2008-02-29 11:43:03 -0800 | [diff] [blame] | 508 | if (dst == NULL) |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 509 | goto out; |
| 510 | |
| 511 | skb = dccp_make_response(sk, dst, req); |
| 512 | if (skb != NULL) { |
| 513 | const struct inet_request_sock *ireq = inet_rsk(req); |
| 514 | struct dccp_hdr *dh = dccp_hdr(skb); |
| 515 | |
Gerrit Renker | 6f4e5ff | 2006-11-10 17:43:06 -0200 | [diff] [blame] | 516 | dh->dccph_checksum = dccp_v4_csum_finish(skb, ireq->loc_addr, |
| 517 | ireq->rmt_addr); |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 518 | err = ip_build_and_send_pkt(skb, sk, ireq->loc_addr, |
| 519 | ireq->rmt_addr, |
| 520 | ireq->opt); |
Gerrit Renker | b9df3cb | 2006-11-14 11:21:36 -0200 | [diff] [blame] | 521 | err = net_xmit_eval(err); |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 522 | } |
| 523 | |
| 524 | out: |
| 525 | dst_release(dst); |
| 526 | return err; |
| 527 | } |
| 528 | |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 529 | static void dccp_v4_ctl_send_reset(struct sock *sk, struct sk_buff *rxskb) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 530 | { |
| 531 | int err; |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 532 | const struct iphdr *rxiph; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 533 | struct sk_buff *skb; |
| 534 | struct dst_entry *dst; |
Eric Dumazet | adf3090 | 2009-06-02 05:19:30 +0000 | [diff] [blame] | 535 | struct net *net = dev_net(skb_dst(rxskb)->dev); |
Pavel Emelyanov | b76c4b2 | 2008-04-13 22:29:59 -0700 | [diff] [blame] | 536 | struct sock *ctl_sk = net->dccp.v4_ctl_sk; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 537 | |
| 538 | /* Never send a reset in response to a reset. */ |
Gerrit Renker | e356d37 | 2007-09-26 14:35:19 -0300 | [diff] [blame] | 539 | if (dccp_hdr(rxskb)->dccph_type == DCCP_PKT_RESET) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 540 | return; |
| 541 | |
Eric Dumazet | 511c3f9 | 2009-06-02 05:14:27 +0000 | [diff] [blame] | 542 | if (skb_rtable(rxskb)->rt_type != RTN_LOCAL) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 543 | return; |
| 544 | |
Pavel Emelyanov | f548739 | 2008-04-13 22:30:19 -0700 | [diff] [blame] | 545 | dst = dccp_v4_route_skb(net, ctl_sk, rxskb); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 546 | if (dst == NULL) |
| 547 | return; |
| 548 | |
Pavel Emelyanov | 7b1cffa | 2008-04-13 22:29:37 -0700 | [diff] [blame] | 549 | skb = dccp_ctl_make_reset(ctl_sk, rxskb); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 550 | if (skb == NULL) |
| 551 | goto out; |
| 552 | |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 553 | rxiph = ip_hdr(rxskb); |
Gerrit Renker | e356d37 | 2007-09-26 14:35:19 -0300 | [diff] [blame] | 554 | dccp_hdr(skb)->dccph_checksum = dccp_v4_csum_finish(skb, rxiph->saddr, |
| 555 | rxiph->daddr); |
Eric Dumazet | adf3090 | 2009-06-02 05:19:30 +0000 | [diff] [blame] | 556 | skb_dst_set(skb, dst_clone(dst)); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 557 | |
Pavel Emelyanov | 7b1cffa | 2008-04-13 22:29:37 -0700 | [diff] [blame] | 558 | bh_lock_sock(ctl_sk); |
| 559 | err = ip_build_and_send_pkt(skb, ctl_sk, |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 560 | rxiph->daddr, rxiph->saddr, NULL); |
Pavel Emelyanov | 7b1cffa | 2008-04-13 22:29:37 -0700 | [diff] [blame] | 561 | bh_unlock_sock(ctl_sk); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 562 | |
Gerrit Renker | b9df3cb | 2006-11-14 11:21:36 -0200 | [diff] [blame] | 563 | if (net_xmit_eval(err) == 0) { |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 564 | DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS); |
| 565 | DCCP_INC_STATS_BH(DCCP_MIB_OUTRSTS); |
| 566 | } |
| 567 | out: |
| 568 | dst_release(dst); |
| 569 | } |
| 570 | |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 571 | static void dccp_v4_reqsk_destructor(struct request_sock *req) |
| 572 | { |
Gerrit Renker | d99a7bd | 2008-11-04 23:56:30 -0800 | [diff] [blame] | 573 | dccp_feat_list_purge(&dccp_rsk(req)->dreq_featneg); |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 574 | kfree(inet_rsk(req)->opt); |
| 575 | } |
| 576 | |
| 577 | static struct request_sock_ops dccp_request_sock_ops __read_mostly = { |
| 578 | .family = PF_INET, |
| 579 | .obj_size = sizeof(struct dccp_request_sock), |
| 580 | .rtx_syn_ack = dccp_v4_send_response, |
| 581 | .send_ack = dccp_reqsk_send_ack, |
| 582 | .destructor = dccp_v4_reqsk_destructor, |
| 583 | .send_reset = dccp_v4_ctl_send_reset, |
| 584 | }; |
| 585 | |
| 586 | int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb) |
| 587 | { |
| 588 | struct inet_request_sock *ireq; |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 589 | struct request_sock *req; |
| 590 | struct dccp_request_sock *dreq; |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 591 | const __be32 service = dccp_hdr_request(skb)->dccph_req_service; |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 592 | struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb); |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 593 | |
| 594 | /* Never answer to DCCP_PKT_REQUESTs send to broadcast or multicast */ |
Eric Dumazet | 511c3f9 | 2009-06-02 05:14:27 +0000 | [diff] [blame] | 595 | if (skb_rtable(skb)->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) |
Gerrit Renker | 4a5409a | 2007-10-04 14:52:28 -0700 | [diff] [blame] | 596 | return 0; /* discard, don't send a reset here */ |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 597 | |
| 598 | if (dccp_bad_service_code(sk, service)) { |
Gerrit Renker | 4a5409a | 2007-10-04 14:52:28 -0700 | [diff] [blame] | 599 | dcb->dccpd_reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE; |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 600 | goto drop; |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 601 | } |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 602 | /* |
| 603 | * TW buckets are converted to open requests without |
| 604 | * limitations, they conserve resources and peer is |
| 605 | * evidently real one. |
| 606 | */ |
Gerrit Renker | 4a5409a | 2007-10-04 14:52:28 -0700 | [diff] [blame] | 607 | dcb->dccpd_reset_code = DCCP_RESET_CODE_TOO_BUSY; |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 608 | if (inet_csk_reqsk_queue_is_full(sk)) |
| 609 | goto drop; |
| 610 | |
| 611 | /* |
| 612 | * Accept backlog is full. If we have already queued enough |
| 613 | * of warm entries in syn queue, drop request. It is better than |
| 614 | * clogging syn queue with openreqs with exponentially increasing |
| 615 | * timeout. |
| 616 | */ |
| 617 | if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1) |
| 618 | goto drop; |
| 619 | |
Arnaldo Carvalho de Melo | ce4a7d0 | 2008-06-10 12:39:35 -0700 | [diff] [blame] | 620 | req = inet_reqsk_alloc(&dccp_request_sock_ops); |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 621 | if (req == NULL) |
| 622 | goto drop; |
| 623 | |
Gerrit Renker | ac75773 | 2008-11-04 23:55:49 -0800 | [diff] [blame] | 624 | if (dccp_reqsk_init(req, dccp_sk(sk), skb)) |
| 625 | goto drop_and_free; |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 626 | |
Gerrit Renker | 8b81941 | 2007-12-13 12:29:24 -0200 | [diff] [blame] | 627 | dreq = dccp_rsk(req); |
| 628 | if (dccp_parse_options(sk, dreq, skb)) |
| 629 | goto drop_and_free; |
| 630 | |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 631 | if (security_inet_conn_request(sk, skb, req)) |
| 632 | goto drop_and_free; |
| 633 | |
| 634 | ireq = inet_rsk(req); |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 635 | ireq->loc_addr = ip_hdr(skb)->daddr; |
| 636 | ireq->rmt_addr = ip_hdr(skb)->saddr; |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 637 | |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 638 | /* |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 639 | * Step 3: Process LISTEN state |
| 640 | * |
| 641 | * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie |
| 642 | * |
Samuel Jero | f541fb7 | 2012-02-26 18:22:02 -0700 | [diff] [blame] | 643 | * Setting S.SWL/S.SWH to is deferred to dccp_create_openreq_child(). |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 644 | */ |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 645 | dreq->dreq_isr = dcb->dccpd_seq; |
Samuel Jero | f541fb7 | 2012-02-26 18:22:02 -0700 | [diff] [blame] | 646 | dreq->dreq_gsr = dreq->dreq_isr; |
Gerrit Renker | 865e902 | 2006-11-13 13:31:50 -0200 | [diff] [blame] | 647 | dreq->dreq_iss = dccp_v4_init_sequence(skb); |
Samuel Jero | f541fb7 | 2012-02-26 18:22:02 -0700 | [diff] [blame] | 648 | dreq->dreq_gss = dreq->dreq_iss; |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 649 | dreq->dreq_service = service; |
| 650 | |
William Allen Simpson | e6b4d11 | 2009-12-02 18:07:39 +0000 | [diff] [blame] | 651 | if (dccp_v4_send_response(sk, req, NULL)) |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 652 | goto drop_and_free; |
| 653 | |
| 654 | inet_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT); |
| 655 | return 0; |
| 656 | |
| 657 | drop_and_free: |
| 658 | reqsk_free(req); |
| 659 | drop: |
| 660 | DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS); |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 661 | return -1; |
| 662 | } |
| 663 | |
| 664 | EXPORT_SYMBOL_GPL(dccp_v4_conn_request); |
| 665 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 666 | int dccp_v4_do_rcv(struct sock *sk, struct sk_buff *skb) |
| 667 | { |
| 668 | struct dccp_hdr *dh = dccp_hdr(skb); |
| 669 | |
| 670 | if (sk->sk_state == DCCP_OPEN) { /* Fast path */ |
| 671 | if (dccp_rcv_established(sk, skb, dh, skb->len)) |
| 672 | goto reset; |
| 673 | return 0; |
| 674 | } |
| 675 | |
| 676 | /* |
| 677 | * Step 3: Process LISTEN state |
Gerrit Renker | d83ca5a | 2006-11-10 16:29:14 -0200 | [diff] [blame] | 678 | * If P.type == Request or P contains a valid Init Cookie option, |
| 679 | * (* Must scan the packet's options to check for Init |
| 680 | * Cookies. Only Init Cookies are processed here, |
| 681 | * however; other options are processed in Step 8. This |
| 682 | * scan need only be performed if the endpoint uses Init |
| 683 | * Cookies *) |
| 684 | * (* Generate a new socket and switch to that socket *) |
| 685 | * Set S := new socket for this port pair |
| 686 | * S.state = RESPOND |
| 687 | * Choose S.ISS (initial seqno) or set from Init Cookies |
| 688 | * Initialize S.GAR := S.ISS |
| 689 | * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookies |
| 690 | * Continue with S.state == RESPOND |
| 691 | * (* A Response packet will be generated in Step 11 *) |
| 692 | * Otherwise, |
| 693 | * Generate Reset(No Connection) unless P.type == Reset |
| 694 | * Drop packet and return |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 695 | * |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 696 | * NOTE: the check for the packet types is done in |
| 697 | * dccp_rcv_state_process |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 698 | */ |
| 699 | if (sk->sk_state == DCCP_LISTEN) { |
| 700 | struct sock *nsk = dccp_v4_hnd_req(sk, skb); |
| 701 | |
| 702 | if (nsk == NULL) |
| 703 | goto discard; |
| 704 | |
| 705 | if (nsk != sk) { |
| 706 | if (dccp_child_process(sk, nsk, skb)) |
| 707 | goto reset; |
| 708 | return 0; |
| 709 | } |
| 710 | } |
| 711 | |
| 712 | if (dccp_rcv_state_process(sk, skb, dh, skb->len)) |
| 713 | goto reset; |
| 714 | return 0; |
| 715 | |
| 716 | reset: |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 717 | dccp_v4_ctl_send_reset(sk, skb); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 718 | discard: |
| 719 | kfree_skb(skb); |
| 720 | return 0; |
| 721 | } |
| 722 | |
Arnaldo Carvalho de Melo | f21e68c | 2005-12-13 23:24:16 -0800 | [diff] [blame] | 723 | EXPORT_SYMBOL_GPL(dccp_v4_do_rcv); |
| 724 | |
Gerrit Renker | 09dbc38 | 2006-11-14 12:57:34 -0200 | [diff] [blame] | 725 | /** |
| 726 | * dccp_invalid_packet - check for malformed packets |
| 727 | * Implements RFC 4340, 8.5: Step 1: Check header basics |
| 728 | * Packets that fail these checks are ignored and do not receive Resets. |
| 729 | */ |
Arnaldo Carvalho de Melo | f21e68c | 2005-12-13 23:24:16 -0800 | [diff] [blame] | 730 | int dccp_invalid_packet(struct sk_buff *skb) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 731 | { |
| 732 | const struct dccp_hdr *dh; |
Gerrit Renker | 6f4e5ff | 2006-11-10 17:43:06 -0200 | [diff] [blame] | 733 | unsigned int cscov; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 734 | |
| 735 | if (skb->pkt_type != PACKET_HOST) |
| 736 | return 1; |
| 737 | |
Gerrit Renker | 09dbc38 | 2006-11-14 12:57:34 -0200 | [diff] [blame] | 738 | /* If the packet is shorter than 12 bytes, drop packet and return */ |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 739 | if (!pskb_may_pull(skb, sizeof(struct dccp_hdr))) { |
Gerrit Renker | 59348b1 | 2006-11-20 18:39:23 -0200 | [diff] [blame] | 740 | DCCP_WARN("pskb_may_pull failed\n"); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 741 | return 1; |
| 742 | } |
| 743 | |
| 744 | dh = dccp_hdr(skb); |
| 745 | |
Gerrit Renker | 09dbc38 | 2006-11-14 12:57:34 -0200 | [diff] [blame] | 746 | /* If P.type is not understood, drop packet and return */ |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 747 | if (dh->dccph_type >= DCCP_PKT_INVALID) { |
Gerrit Renker | 59348b1 | 2006-11-20 18:39:23 -0200 | [diff] [blame] | 748 | DCCP_WARN("invalid packet type\n"); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 749 | return 1; |
| 750 | } |
| 751 | |
| 752 | /* |
Gerrit Renker | 09dbc38 | 2006-11-14 12:57:34 -0200 | [diff] [blame] | 753 | * If P.Data Offset is too small for packet type, drop packet and return |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 754 | */ |
| 755 | if (dh->dccph_doff < dccp_hdr_len(skb) / sizeof(u32)) { |
Gerrit Renker | 59348b1 | 2006-11-20 18:39:23 -0200 | [diff] [blame] | 756 | DCCP_WARN("P.Data Offset(%u) too small\n", dh->dccph_doff); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 757 | return 1; |
| 758 | } |
Gerrit Renker | 09dbc38 | 2006-11-14 12:57:34 -0200 | [diff] [blame] | 759 | /* |
| 760 | * If P.Data Offset is too too large for packet, drop packet and return |
| 761 | */ |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 762 | if (!pskb_may_pull(skb, dh->dccph_doff * sizeof(u32))) { |
Gerrit Renker | 59348b1 | 2006-11-20 18:39:23 -0200 | [diff] [blame] | 763 | DCCP_WARN("P.Data Offset(%u) too large\n", dh->dccph_doff); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 764 | return 1; |
| 765 | } |
| 766 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 767 | /* |
| 768 | * If P.type is not Data, Ack, or DataAck and P.X == 0 (the packet |
| 769 | * has short sequence numbers), drop packet and return |
| 770 | */ |
Wei Yongjun | 6079a46 | 2008-05-27 06:22:38 -0700 | [diff] [blame] | 771 | if ((dh->dccph_type < DCCP_PKT_DATA || |
| 772 | dh->dccph_type > DCCP_PKT_DATAACK) && dh->dccph_x == 0) { |
Gerrit Renker | 59348b1 | 2006-11-20 18:39:23 -0200 | [diff] [blame] | 773 | DCCP_WARN("P.type (%s) not Data || [Data]Ack, while P.X == 0\n", |
| 774 | dccp_packet_name(dh->dccph_type)); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 775 | return 1; |
| 776 | } |
| 777 | |
Gerrit Renker | 6f4e5ff | 2006-11-10 17:43:06 -0200 | [diff] [blame] | 778 | /* |
| 779 | * If P.CsCov is too large for the packet size, drop packet and return. |
| 780 | * This must come _before_ checksumming (not as RFC 4340 suggests). |
| 781 | */ |
| 782 | cscov = dccp_csum_coverage(skb); |
| 783 | if (cscov > skb->len) { |
Gerrit Renker | 59348b1 | 2006-11-20 18:39:23 -0200 | [diff] [blame] | 784 | DCCP_WARN("P.CsCov %u exceeds packet length %d\n", |
| 785 | dh->dccph_cscov, skb->len); |
Gerrit Renker | 6f4e5ff | 2006-11-10 17:43:06 -0200 | [diff] [blame] | 786 | return 1; |
| 787 | } |
| 788 | |
| 789 | /* If header checksum is incorrect, drop packet and return. |
| 790 | * (This step is completed in the AF-dependent functions.) */ |
| 791 | skb->csum = skb_checksum(skb, 0, cscov, 0); |
| 792 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 793 | return 0; |
| 794 | } |
| 795 | |
Arnaldo Carvalho de Melo | f21e68c | 2005-12-13 23:24:16 -0800 | [diff] [blame] | 796 | EXPORT_SYMBOL_GPL(dccp_invalid_packet); |
| 797 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 798 | /* this is called when real data arrives */ |
Arnaldo Carvalho de Melo | b61fafc | 2006-03-20 21:25:11 -0800 | [diff] [blame] | 799 | static int dccp_v4_rcv(struct sk_buff *skb) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 800 | { |
| 801 | const struct dccp_hdr *dh; |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 802 | const struct iphdr *iph; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 803 | struct sock *sk; |
Gerrit Renker | 6f4e5ff | 2006-11-10 17:43:06 -0200 | [diff] [blame] | 804 | int min_cov; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 805 | |
Gerrit Renker | 6f4e5ff | 2006-11-10 17:43:06 -0200 | [diff] [blame] | 806 | /* Step 1: Check header basics */ |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 807 | |
| 808 | if (dccp_invalid_packet(skb)) |
| 809 | goto discard_it; |
| 810 | |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 811 | iph = ip_hdr(skb); |
Gerrit Renker | 6f4e5ff | 2006-11-10 17:43:06 -0200 | [diff] [blame] | 812 | /* Step 1: If header checksum is incorrect, drop packet and return */ |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 813 | if (dccp_v4_csum_finish(skb, iph->saddr, iph->daddr)) { |
Gerrit Renker | 59348b1 | 2006-11-20 18:39:23 -0200 | [diff] [blame] | 814 | DCCP_WARN("dropped packet with invalid checksum\n"); |
Arnaldo Carvalho de Melo | f21e68c | 2005-12-13 23:24:16 -0800 | [diff] [blame] | 815 | goto discard_it; |
| 816 | } |
| 817 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 818 | dh = dccp_hdr(skb); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 819 | |
Gerrit Renker | fde2010 | 2007-10-24 10:12:09 -0200 | [diff] [blame] | 820 | DCCP_SKB_CB(skb)->dccpd_seq = dccp_hdr_seq(dh); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 821 | DCCP_SKB_CB(skb)->dccpd_type = dh->dccph_type; |
| 822 | |
Harvey Harrison | 21454aa | 2008-10-31 00:54:56 -0700 | [diff] [blame] | 823 | dccp_pr_debug("%8.8s src=%pI4@%-5d dst=%pI4@%-5d seq=%llu", |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 824 | dccp_packet_name(dh->dccph_type), |
Harvey Harrison | 21454aa | 2008-10-31 00:54:56 -0700 | [diff] [blame] | 825 | &iph->saddr, ntohs(dh->dccph_sport), |
| 826 | &iph->daddr, ntohs(dh->dccph_dport), |
David S. Miller | f6ccf55 | 2005-08-09 20:27:14 -0700 | [diff] [blame] | 827 | (unsigned long long) DCCP_SKB_CB(skb)->dccpd_seq); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 828 | |
| 829 | if (dccp_packet_without_ack(skb)) { |
| 830 | DCCP_SKB_CB(skb)->dccpd_ack_seq = DCCP_PKT_WITHOUT_ACK_SEQ; |
| 831 | dccp_pr_debug_cat("\n"); |
| 832 | } else { |
| 833 | DCCP_SKB_CB(skb)->dccpd_ack_seq = dccp_hdr_ack_seq(skb); |
Gerrit Renker | d23c710 | 2006-11-10 11:46:34 -0200 | [diff] [blame] | 834 | dccp_pr_debug_cat(", ack=%llu\n", (unsigned long long) |
David S. Miller | f6ccf55 | 2005-08-09 20:27:14 -0700 | [diff] [blame] | 835 | DCCP_SKB_CB(skb)->dccpd_ack_seq); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 836 | } |
| 837 | |
| 838 | /* Step 2: |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 839 | * Look up flow ID in table and get corresponding socket */ |
Arnaldo Carvalho de Melo | 9a1f27c | 2008-10-07 11:41:57 -0700 | [diff] [blame] | 840 | sk = __inet_lookup_skb(&dccp_hashinfo, skb, |
| 841 | dh->dccph_sport, dh->dccph_dport); |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 842 | /* |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 843 | * Step 2: |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 844 | * If no socket ... |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 845 | */ |
| 846 | if (sk == NULL) { |
| 847 | dccp_pr_debug("failed to look up flow ID in table and " |
| 848 | "get corresponding socket\n"); |
| 849 | goto no_dccp_socket; |
| 850 | } |
| 851 | |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 852 | /* |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 853 | * Step 2: |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 854 | * ... or S.state == TIMEWAIT, |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 855 | * Generate Reset(No Connection) unless P.type == Reset |
| 856 | * Drop packet and return |
| 857 | */ |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 858 | if (sk->sk_state == DCCP_TIME_WAIT) { |
Gerrit Renker | d23c710 | 2006-11-10 11:46:34 -0200 | [diff] [blame] | 859 | dccp_pr_debug("sk->sk_state == DCCP_TIME_WAIT: do_time_wait\n"); |
| 860 | inet_twsk_put(inet_twsk(sk)); |
| 861 | goto no_dccp_socket; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 862 | } |
| 863 | |
Gerrit Renker | 6f4e5ff | 2006-11-10 17:43:06 -0200 | [diff] [blame] | 864 | /* |
| 865 | * RFC 4340, sec. 9.2.1: Minimum Checksum Coverage |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 866 | * o if MinCsCov = 0, only packets with CsCov = 0 are accepted |
| 867 | * o if MinCsCov > 0, also accept packets with CsCov >= MinCsCov |
Gerrit Renker | 6f4e5ff | 2006-11-10 17:43:06 -0200 | [diff] [blame] | 868 | */ |
| 869 | min_cov = dccp_sk(sk)->dccps_pcrlen; |
| 870 | if (dh->dccph_cscov && (min_cov == 0 || dh->dccph_cscov < min_cov)) { |
| 871 | dccp_pr_debug("Packet CsCov %d does not satisfy MinCsCov %d\n", |
| 872 | dh->dccph_cscov, min_cov); |
| 873 | /* FIXME: "Such packets SHOULD be reported using Data Dropped |
| 874 | * options (Section 11.7) with Drop Code 0, Protocol |
| 875 | * Constraints." */ |
| 876 | goto discard_and_relse; |
| 877 | } |
| 878 | |
Arnaldo Carvalho de Melo | 25995ff | 2005-12-27 02:42:22 -0200 | [diff] [blame] | 879 | if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 880 | goto discard_and_relse; |
Patrick McHardy | eb9c7eb | 2006-01-06 23:06:30 -0800 | [diff] [blame] | 881 | nf_reset(skb); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 882 | |
Arnaldo Carvalho de Melo | 58a5a7b | 2006-11-16 14:06:06 -0200 | [diff] [blame] | 883 | return sk_receive_skb(sk, skb, 1); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 884 | |
| 885 | no_dccp_socket: |
| 886 | if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) |
| 887 | goto discard_it; |
| 888 | /* |
| 889 | * Step 2: |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 890 | * If no socket ... |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 891 | * Generate Reset(No Connection) unless P.type == Reset |
| 892 | * Drop packet and return |
| 893 | */ |
| 894 | if (dh->dccph_type != DCCP_PKT_RESET) { |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 895 | DCCP_SKB_CB(skb)->dccpd_reset_code = |
| 896 | DCCP_RESET_CODE_NO_CONNECTION; |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 897 | dccp_v4_ctl_send_reset(sk, skb); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 898 | } |
| 899 | |
| 900 | discard_it: |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 901 | kfree_skb(skb); |
| 902 | return 0; |
| 903 | |
| 904 | discard_and_relse: |
| 905 | sock_put(sk); |
| 906 | goto discard_it; |
| 907 | } |
| 908 | |
Stephen Hemminger | 3b401a8 | 2009-09-01 19:25:04 +0000 | [diff] [blame] | 909 | static const struct inet_connection_sock_af_ops dccp_ipv4_af_ops = { |
Arnaldo Carvalho de Melo | 543d9cf | 2006-03-20 22:48:35 -0800 | [diff] [blame] | 910 | .queue_xmit = ip_queue_xmit, |
| 911 | .send_check = dccp_v4_send_check, |
| 912 | .rebuild_header = inet_sk_rebuild_header, |
| 913 | .conn_request = dccp_v4_conn_request, |
| 914 | .syn_recv_sock = dccp_v4_request_recv_sock, |
| 915 | .net_header_len = sizeof(struct iphdr), |
| 916 | .setsockopt = ip_setsockopt, |
| 917 | .getsockopt = ip_getsockopt, |
| 918 | .addr2sockaddr = inet_csk_addr2sockaddr, |
| 919 | .sockaddr_len = sizeof(struct sockaddr_in), |
Arnaldo Carvalho de Melo | ab1e0a1 | 2008-02-03 04:06:04 -0800 | [diff] [blame] | 920 | .bind_conflict = inet_csk_bind_conflict, |
Dmitry Mishin | 3fdadf7 | 2006-03-20 22:45:21 -0800 | [diff] [blame] | 921 | #ifdef CONFIG_COMPAT |
Arnaldo Carvalho de Melo | 543d9cf | 2006-03-20 22:48:35 -0800 | [diff] [blame] | 922 | .compat_setsockopt = compat_ip_setsockopt, |
| 923 | .compat_getsockopt = compat_ip_getsockopt, |
Dmitry Mishin | 3fdadf7 | 2006-03-20 22:45:21 -0800 | [diff] [blame] | 924 | #endif |
Arnaldo Carvalho de Melo | 57cca05 | 2005-12-13 23:16:16 -0800 | [diff] [blame] | 925 | }; |
| 926 | |
Arnaldo Carvalho de Melo | 3e0fadc | 2006-03-20 21:23:15 -0800 | [diff] [blame] | 927 | static int dccp_v4_init_sock(struct sock *sk) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 928 | { |
Arnaldo Carvalho de Melo | 7247887 | 2006-03-20 22:00:37 -0800 | [diff] [blame] | 929 | static __u8 dccp_v4_ctl_sock_initialized; |
| 930 | int err = dccp_init_sock(sk, dccp_v4_ctl_sock_initialized); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 931 | |
Arnaldo Carvalho de Melo | 7247887 | 2006-03-20 22:00:37 -0800 | [diff] [blame] | 932 | if (err == 0) { |
| 933 | if (unlikely(!dccp_v4_ctl_sock_initialized)) |
| 934 | dccp_v4_ctl_sock_initialized = 1; |
Arnaldo Carvalho de Melo | 3e0fadc | 2006-03-20 21:23:15 -0800 | [diff] [blame] | 935 | inet_csk(sk)->icsk_af_ops = &dccp_ipv4_af_ops; |
Arnaldo Carvalho de Melo | 7247887 | 2006-03-20 22:00:37 -0800 | [diff] [blame] | 936 | } |
| 937 | |
Arnaldo Carvalho de Melo | 3e0fadc | 2006-03-20 21:23:15 -0800 | [diff] [blame] | 938 | return err; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 939 | } |
| 940 | |
Arnaldo Carvalho de Melo | 6d6ee43 | 2005-12-13 23:25:19 -0800 | [diff] [blame] | 941 | static struct timewait_sock_ops dccp_timewait_sock_ops = { |
| 942 | .twsk_obj_size = sizeof(struct inet_timewait_sock), |
| 943 | }; |
| 944 | |
Adrian Bunk | 5e0817f | 2006-03-20 21:58:29 -0800 | [diff] [blame] | 945 | static struct proto dccp_v4_prot = { |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 946 | .name = "DCCP", |
| 947 | .owner = THIS_MODULE, |
| 948 | .close = dccp_close, |
| 949 | .connect = dccp_v4_connect, |
| 950 | .disconnect = dccp_disconnect, |
| 951 | .ioctl = dccp_ioctl, |
| 952 | .init = dccp_v4_init_sock, |
| 953 | .setsockopt = dccp_setsockopt, |
| 954 | .getsockopt = dccp_getsockopt, |
| 955 | .sendmsg = dccp_sendmsg, |
| 956 | .recvmsg = dccp_recvmsg, |
| 957 | .backlog_rcv = dccp_v4_do_rcv, |
Arnaldo Carvalho de Melo | ab1e0a1 | 2008-02-03 04:06:04 -0800 | [diff] [blame] | 958 | .hash = inet_hash, |
| 959 | .unhash = inet_unhash, |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 960 | .accept = inet_csk_accept, |
Arnaldo Carvalho de Melo | ab1e0a1 | 2008-02-03 04:06:04 -0800 | [diff] [blame] | 961 | .get_port = inet_csk_get_port, |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 962 | .shutdown = dccp_shutdown, |
Arnaldo Carvalho de Melo | 3e0fadc | 2006-03-20 21:23:15 -0800 | [diff] [blame] | 963 | .destroy = dccp_destroy_sock, |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 964 | .orphan_count = &dccp_orphan_count, |
| 965 | .max_header = MAX_DCCP_HEADER, |
| 966 | .obj_size = sizeof(struct dccp_sock), |
Eric Dumazet | 3ab5aee | 2008-11-16 19:40:17 -0800 | [diff] [blame] | 967 | .slab_flags = SLAB_DESTROY_BY_RCU, |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 968 | .rsk_prot = &dccp_request_sock_ops, |
Arnaldo Carvalho de Melo | 6d6ee43 | 2005-12-13 23:25:19 -0800 | [diff] [blame] | 969 | .twsk_prot = &dccp_timewait_sock_ops, |
Pavel Emelyanov | 39d8cda | 2008-03-22 16:50:58 -0700 | [diff] [blame] | 970 | .h.hashinfo = &dccp_hashinfo, |
Arnaldo Carvalho de Melo | 543d9cf | 2006-03-20 22:48:35 -0800 | [diff] [blame] | 971 | #ifdef CONFIG_COMPAT |
| 972 | .compat_setsockopt = compat_dccp_setsockopt, |
| 973 | .compat_getsockopt = compat_dccp_getsockopt, |
| 974 | #endif |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 975 | }; |
Arnaldo Carvalho de Melo | 6d6ee43 | 2005-12-13 23:25:19 -0800 | [diff] [blame] | 976 | |
Alexey Dobriyan | 3261309 | 2009-09-14 12:21:47 +0000 | [diff] [blame] | 977 | static const struct net_protocol dccp_v4_protocol = { |
Arnaldo Carvalho de Melo | b61fafc | 2006-03-20 21:25:11 -0800 | [diff] [blame] | 978 | .handler = dccp_v4_rcv, |
| 979 | .err_handler = dccp_v4_err, |
| 980 | .no_policy = 1, |
Pavel Emelyanov | fc5f858 | 2008-04-13 22:31:05 -0700 | [diff] [blame] | 981 | .netns_ok = 1, |
Arnaldo Carvalho de Melo | b61fafc | 2006-03-20 21:25:11 -0800 | [diff] [blame] | 982 | }; |
| 983 | |
| 984 | static const struct proto_ops inet_dccp_ops = { |
Arnaldo Carvalho de Melo | 543d9cf | 2006-03-20 22:48:35 -0800 | [diff] [blame] | 985 | .family = PF_INET, |
| 986 | .owner = THIS_MODULE, |
| 987 | .release = inet_release, |
| 988 | .bind = inet_bind, |
| 989 | .connect = inet_stream_connect, |
| 990 | .socketpair = sock_no_socketpair, |
| 991 | .accept = inet_accept, |
| 992 | .getname = inet_getname, |
Arnaldo Carvalho de Melo | b61fafc | 2006-03-20 21:25:11 -0800 | [diff] [blame] | 993 | /* FIXME: work on tcp_poll to rename it to inet_csk_poll */ |
Arnaldo Carvalho de Melo | 543d9cf | 2006-03-20 22:48:35 -0800 | [diff] [blame] | 994 | .poll = dccp_poll, |
| 995 | .ioctl = inet_ioctl, |
Arnaldo Carvalho de Melo | b61fafc | 2006-03-20 21:25:11 -0800 | [diff] [blame] | 996 | /* FIXME: work on inet_listen to rename it to sock_common_listen */ |
Arnaldo Carvalho de Melo | 543d9cf | 2006-03-20 22:48:35 -0800 | [diff] [blame] | 997 | .listen = inet_dccp_listen, |
| 998 | .shutdown = inet_shutdown, |
| 999 | .setsockopt = sock_common_setsockopt, |
| 1000 | .getsockopt = sock_common_getsockopt, |
| 1001 | .sendmsg = inet_sendmsg, |
| 1002 | .recvmsg = sock_common_recvmsg, |
| 1003 | .mmap = sock_no_mmap, |
| 1004 | .sendpage = sock_no_sendpage, |
Dmitry Mishin | 3fdadf7 | 2006-03-20 22:45:21 -0800 | [diff] [blame] | 1005 | #ifdef CONFIG_COMPAT |
Arnaldo Carvalho de Melo | 543d9cf | 2006-03-20 22:48:35 -0800 | [diff] [blame] | 1006 | .compat_setsockopt = compat_sock_common_setsockopt, |
| 1007 | .compat_getsockopt = compat_sock_common_getsockopt, |
Dmitry Mishin | 3fdadf7 | 2006-03-20 22:45:21 -0800 | [diff] [blame] | 1008 | #endif |
Arnaldo Carvalho de Melo | b61fafc | 2006-03-20 21:25:11 -0800 | [diff] [blame] | 1009 | }; |
| 1010 | |
| 1011 | static struct inet_protosw dccp_v4_protosw = { |
| 1012 | .type = SOCK_DCCP, |
| 1013 | .protocol = IPPROTO_DCCP, |
| 1014 | .prot = &dccp_v4_prot, |
| 1015 | .ops = &inet_dccp_ops, |
Arnaldo Carvalho de Melo | b61fafc | 2006-03-20 21:25:11 -0800 | [diff] [blame] | 1016 | .no_check = 0, |
| 1017 | .flags = INET_PROTOSW_ICSK, |
| 1018 | }; |
| 1019 | |
Alexey Dobriyan | 2c8c1e7 | 2010-01-17 03:35:32 +0000 | [diff] [blame] | 1020 | static int __net_init dccp_v4_init_net(struct net *net) |
Pavel Emelyanov | 72a2d61 | 2008-04-13 22:29:13 -0700 | [diff] [blame] | 1021 | { |
Gerrit Renker | d14a0eb | 2010-03-14 20:13:19 +0000 | [diff] [blame] | 1022 | if (dccp_hashinfo.bhash == NULL) |
| 1023 | return -ESOCKTNOSUPPORT; |
Pavel Emelyanov | b76c4b2 | 2008-04-13 22:29:59 -0700 | [diff] [blame] | 1024 | |
Gerrit Renker | d14a0eb | 2010-03-14 20:13:19 +0000 | [diff] [blame] | 1025 | return inet_ctl_sock_create(&net->dccp.v4_ctl_sk, PF_INET, |
| 1026 | SOCK_DCCP, IPPROTO_DCCP, net); |
Pavel Emelyanov | 72a2d61 | 2008-04-13 22:29:13 -0700 | [diff] [blame] | 1027 | } |
| 1028 | |
Alexey Dobriyan | 2c8c1e7 | 2010-01-17 03:35:32 +0000 | [diff] [blame] | 1029 | static void __net_exit dccp_v4_exit_net(struct net *net) |
Pavel Emelyanov | 72a2d61 | 2008-04-13 22:29:13 -0700 | [diff] [blame] | 1030 | { |
Pavel Emelyanov | b76c4b2 | 2008-04-13 22:29:59 -0700 | [diff] [blame] | 1031 | inet_ctl_sock_destroy(net->dccp.v4_ctl_sk); |
Pavel Emelyanov | 72a2d61 | 2008-04-13 22:29:13 -0700 | [diff] [blame] | 1032 | } |
| 1033 | |
| 1034 | static struct pernet_operations dccp_v4_ops = { |
| 1035 | .init = dccp_v4_init_net, |
| 1036 | .exit = dccp_v4_exit_net, |
| 1037 | }; |
| 1038 | |
Arnaldo Carvalho de Melo | b61fafc | 2006-03-20 21:25:11 -0800 | [diff] [blame] | 1039 | static int __init dccp_v4_init(void) |
| 1040 | { |
| 1041 | int err = proto_register(&dccp_v4_prot, 1); |
| 1042 | |
| 1043 | if (err != 0) |
| 1044 | goto out; |
| 1045 | |
| 1046 | err = inet_add_protocol(&dccp_v4_protocol, IPPROTO_DCCP); |
| 1047 | if (err != 0) |
| 1048 | goto out_proto_unregister; |
| 1049 | |
| 1050 | inet_register_protosw(&dccp_v4_protosw); |
| 1051 | |
Pavel Emelyanov | 72a2d61 | 2008-04-13 22:29:13 -0700 | [diff] [blame] | 1052 | err = register_pernet_subsys(&dccp_v4_ops); |
| 1053 | if (err) |
| 1054 | goto out_destroy_ctl_sock; |
Arnaldo Carvalho de Melo | b61fafc | 2006-03-20 21:25:11 -0800 | [diff] [blame] | 1055 | out: |
| 1056 | return err; |
Pavel Emelyanov | 72a2d61 | 2008-04-13 22:29:13 -0700 | [diff] [blame] | 1057 | out_destroy_ctl_sock: |
Arnaldo Carvalho de Melo | b61fafc | 2006-03-20 21:25:11 -0800 | [diff] [blame] | 1058 | inet_unregister_protosw(&dccp_v4_protosw); |
| 1059 | inet_del_protocol(&dccp_v4_protocol, IPPROTO_DCCP); |
| 1060 | out_proto_unregister: |
| 1061 | proto_unregister(&dccp_v4_prot); |
| 1062 | goto out; |
| 1063 | } |
| 1064 | |
| 1065 | static void __exit dccp_v4_exit(void) |
| 1066 | { |
Pavel Emelyanov | 72a2d61 | 2008-04-13 22:29:13 -0700 | [diff] [blame] | 1067 | unregister_pernet_subsys(&dccp_v4_ops); |
Arnaldo Carvalho de Melo | b61fafc | 2006-03-20 21:25:11 -0800 | [diff] [blame] | 1068 | inet_unregister_protosw(&dccp_v4_protosw); |
| 1069 | inet_del_protocol(&dccp_v4_protocol, IPPROTO_DCCP); |
| 1070 | proto_unregister(&dccp_v4_prot); |
| 1071 | } |
| 1072 | |
| 1073 | module_init(dccp_v4_init); |
| 1074 | module_exit(dccp_v4_exit); |
| 1075 | |
| 1076 | /* |
| 1077 | * __stringify doesn't likes enums, so use SOCK_DCCP (6) and IPPROTO_DCCP (33) |
| 1078 | * values directly, Also cover the case where the protocol is not specified, |
| 1079 | * i.e. net-pf-PF_INET-proto-0-type-SOCK_DCCP |
| 1080 | */ |
Jean Delvare | 7131c6c | 2007-10-21 16:45:03 -0700 | [diff] [blame] | 1081 | MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET, 33, 6); |
| 1082 | MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET, 0, 6); |
Arnaldo Carvalho de Melo | b61fafc | 2006-03-20 21:25:11 -0800 | [diff] [blame] | 1083 | MODULE_LICENSE("GPL"); |
| 1084 | MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@mandriva.com>"); |
| 1085 | MODULE_DESCRIPTION("DCCP - Datagram Congestion Controlled Protocol"); |