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> |
| 29 | |
Arnaldo Carvalho de Melo | ae31c33 | 2005-09-18 00:17:51 -0700 | [diff] [blame] | 30 | #include "ackvec.h" |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 31 | #include "ccid.h" |
| 32 | #include "dccp.h" |
Andrea Bittau | afe0025 | 2006-03-20 17:43:56 -0800 | [diff] [blame] | 33 | #include "feat.h" |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 34 | |
Arnaldo Carvalho de Melo | 7247887 | 2006-03-20 22:00:37 -0800 | [diff] [blame] | 35 | /* |
Pavel Emelyanov | 13f51d8 | 2008-04-14 02:38:45 -0700 | [diff] [blame] | 36 | * 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] | 37 | * the Out-of-the-blue (OOTB) packets. A control sock will be created |
| 38 | * for this socket at the initialization time. |
| 39 | */ |
Arnaldo Carvalho de Melo | 7247887 | 2006-03-20 22:00:37 -0800 | [diff] [blame] | 40 | |
Arnaldo Carvalho de Melo | f21e68c | 2005-12-13 23:24:16 -0800 | [diff] [blame] | 41 | 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] | 42 | { |
| 43 | struct inet_sock *inet = inet_sk(sk); |
| 44 | struct dccp_sock *dp = dccp_sk(sk); |
| 45 | const struct sockaddr_in *usin = (struct sockaddr_in *)uaddr; |
| 46 | struct rtable *rt; |
Al Viro | bada8ad | 2006-09-26 21:27:15 -0700 | [diff] [blame] | 47 | __be32 daddr, nexthop; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 48 | int tmp; |
| 49 | int err; |
| 50 | |
| 51 | dp->dccps_role = DCCP_ROLE_CLIENT; |
| 52 | |
| 53 | if (addr_len < sizeof(struct sockaddr_in)) |
| 54 | return -EINVAL; |
| 55 | |
| 56 | if (usin->sin_family != AF_INET) |
| 57 | return -EAFNOSUPPORT; |
| 58 | |
| 59 | nexthop = daddr = usin->sin_addr.s_addr; |
| 60 | if (inet->opt != NULL && inet->opt->srr) { |
| 61 | if (daddr == 0) |
| 62 | return -EINVAL; |
| 63 | nexthop = inet->opt->faddr; |
| 64 | } |
| 65 | |
Eric Dumazet | c720c7e | 2009-10-15 06:30:45 +0000 | [diff] [blame] | 66 | tmp = ip_route_connect(&rt, nexthop, inet->inet_saddr, |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 67 | RT_CONN_FLAGS(sk), sk->sk_bound_dev_if, |
| 68 | IPPROTO_DCCP, |
Eric Dumazet | c720c7e | 2009-10-15 06:30:45 +0000 | [diff] [blame] | 69 | inet->inet_sport, usin->sin_port, sk, 1); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 70 | if (tmp < 0) |
| 71 | return tmp; |
| 72 | |
| 73 | if (rt->rt_flags & (RTCF_MULTICAST | RTCF_BROADCAST)) { |
| 74 | ip_rt_put(rt); |
| 75 | return -ENETUNREACH; |
| 76 | } |
| 77 | |
| 78 | if (inet->opt == NULL || !inet->opt->srr) |
| 79 | daddr = rt->rt_dst; |
| 80 | |
Eric Dumazet | c720c7e | 2009-10-15 06:30:45 +0000 | [diff] [blame] | 81 | if (inet->inet_saddr == 0) |
| 82 | inet->inet_saddr = rt->rt_src; |
| 83 | inet->inet_rcv_saddr = inet->inet_saddr; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 84 | |
Eric Dumazet | c720c7e | 2009-10-15 06:30:45 +0000 | [diff] [blame] | 85 | inet->inet_dport = usin->sin_port; |
| 86 | inet->inet_daddr = daddr; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 87 | |
Arnaldo Carvalho de Melo | d83d846 | 2005-12-13 23:26:10 -0800 | [diff] [blame] | 88 | inet_csk(sk)->icsk_ext_hdr_len = 0; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 89 | if (inet->opt != NULL) |
Arnaldo Carvalho de Melo | d83d846 | 2005-12-13 23:26:10 -0800 | [diff] [blame] | 90 | inet_csk(sk)->icsk_ext_hdr_len = inet->opt->optlen; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 91 | /* |
| 92 | * Socket identity is still unknown (sport may be zero). |
| 93 | * However we set state to DCCP_REQUESTING and not releasing socket |
| 94 | * lock select source port, enter ourselves into the hash tables and |
| 95 | * complete initialization after this. |
| 96 | */ |
| 97 | dccp_set_state(sk, DCCP_REQUESTING); |
Arnaldo Carvalho de Melo | a7f5e7f | 2005-12-13 23:25:31 -0800 | [diff] [blame] | 98 | err = inet_hash_connect(&dccp_death_row, sk); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 99 | if (err != 0) |
| 100 | goto failure; |
| 101 | |
Eric Dumazet | c720c7e | 2009-10-15 06:30:45 +0000 | [diff] [blame] | 102 | err = ip_route_newports(&rt, IPPROTO_DCCP, inet->inet_sport, |
| 103 | inet->inet_dport, sk); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 104 | if (err != 0) |
| 105 | goto failure; |
| 106 | |
| 107 | /* OK, now commit destination to socket. */ |
| 108 | sk_setup_caps(sk, &rt->u.dst); |
| 109 | |
Eric Dumazet | c720c7e | 2009-10-15 06:30:45 +0000 | [diff] [blame] | 110 | dp->dccps_iss = secure_dccp_sequence_number(inet->inet_saddr, |
| 111 | inet->inet_daddr, |
| 112 | inet->inet_sport, |
| 113 | inet->inet_dport); |
| 114 | inet->inet_id = dp->dccps_iss ^ jiffies; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 115 | |
| 116 | err = dccp_connect(sk); |
| 117 | rt = NULL; |
| 118 | if (err != 0) |
| 119 | goto failure; |
| 120 | out: |
| 121 | return err; |
| 122 | failure: |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 123 | /* |
| 124 | * This unhashes the socket and releases the local port, if necessary. |
| 125 | */ |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 126 | dccp_set_state(sk, DCCP_CLOSED); |
| 127 | ip_rt_put(rt); |
| 128 | sk->sk_route_caps = 0; |
Eric Dumazet | c720c7e | 2009-10-15 06:30:45 +0000 | [diff] [blame] | 129 | inet->inet_dport = 0; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 130 | goto out; |
| 131 | } |
| 132 | |
Arnaldo Carvalho de Melo | f21e68c | 2005-12-13 23:24:16 -0800 | [diff] [blame] | 133 | EXPORT_SYMBOL_GPL(dccp_v4_connect); |
| 134 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 135 | /* |
| 136 | * This routine does path mtu discovery as defined in RFC1191. |
| 137 | */ |
| 138 | static inline void dccp_do_pmtu_discovery(struct sock *sk, |
| 139 | const struct iphdr *iph, |
| 140 | u32 mtu) |
| 141 | { |
| 142 | struct dst_entry *dst; |
| 143 | const struct inet_sock *inet = inet_sk(sk); |
| 144 | const struct dccp_sock *dp = dccp_sk(sk); |
| 145 | |
| 146 | /* We are not interested in DCCP_LISTEN and request_socks (RESPONSEs |
| 147 | * send out by Linux are always < 576bytes so they should go through |
| 148 | * unfragmented). |
| 149 | */ |
| 150 | if (sk->sk_state == DCCP_LISTEN) |
| 151 | return; |
| 152 | |
| 153 | /* We don't check in the destentry if pmtu discovery is forbidden |
| 154 | * on this route. We just assume that no packet_to_big packets |
| 155 | * are send back when pmtu discovery is not active. |
YOSHIFUJI Hideaki | c9eaf17 | 2007-02-09 23:24:38 +0900 | [diff] [blame] | 156 | * 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] | 157 | * route, but I think that's acceptable. |
| 158 | */ |
| 159 | if ((dst = __sk_dst_check(sk, 0)) == NULL) |
| 160 | return; |
| 161 | |
| 162 | dst->ops->update_pmtu(dst, mtu); |
| 163 | |
| 164 | /* Something is about to be wrong... Remember soft error |
| 165 | * for the case, if this connection will not able to recover. |
| 166 | */ |
| 167 | if (mtu < dst_mtu(dst) && ip_dont_fragment(sk, dst)) |
| 168 | sk->sk_err_soft = EMSGSIZE; |
| 169 | |
| 170 | mtu = dst_mtu(dst); |
| 171 | |
| 172 | if (inet->pmtudisc != IP_PMTUDISC_DONT && |
Arnaldo Carvalho de Melo | d83d846 | 2005-12-13 23:26:10 -0800 | [diff] [blame] | 173 | inet_csk(sk)->icsk_pmtu_cookie > mtu) { |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 174 | dccp_sync_mss(sk, mtu); |
| 175 | |
| 176 | /* |
Gerrit Renker | 0e64e94 | 2006-10-24 16:17:51 -0700 | [diff] [blame] | 177 | * From RFC 4340, sec. 14.1: |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 178 | * |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 179 | * DCCP-Sync packets are the best choice for upward |
| 180 | * probing, since DCCP-Sync probes do not risk application |
| 181 | * data loss. |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 182 | */ |
Arnaldo Carvalho de Melo | e92ae93 | 2005-08-17 03:10:59 -0300 | [diff] [blame] | 183 | dccp_send_sync(sk, dp->dccps_gsr, DCCP_PKT_SYNC); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 184 | } /* else let the usual retransmit timer handle it */ |
| 185 | } |
| 186 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 187 | /* |
| 188 | * This routine is called by the ICMP module when it gets some sort of error |
| 189 | * condition. If err < 0 then the socket should be closed and the error |
| 190 | * returned to the user. If err > 0 it's just the icmp type << 8 | icmp code. |
| 191 | * After adjustment header points to the first 8 bytes of the tcp header. We |
| 192 | * need to find the appropriate port. |
| 193 | * |
| 194 | * The locking strategy used here is very "optimistic". When someone else |
| 195 | * accesses the socket the ICMP is just dropped and for some paths there is no |
| 196 | * check at all. A more general error queue to queue errors for later handling |
| 197 | * is probably better. |
| 198 | */ |
Arnaldo Carvalho de Melo | b61fafc | 2006-03-20 21:25:11 -0800 | [diff] [blame] | 199 | 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] | 200 | { |
| 201 | const struct iphdr *iph = (struct iphdr *)skb->data; |
Wei Yongjun | 18e1d83 | 2008-07-26 11:59:10 +0100 | [diff] [blame] | 202 | const u8 offset = iph->ihl << 2; |
| 203 | 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] | 204 | struct dccp_sock *dp; |
| 205 | struct inet_sock *inet; |
Arnaldo Carvalho de Melo | 88c7664 | 2007-03-13 14:43:18 -0300 | [diff] [blame] | 206 | const int type = icmp_hdr(skb)->type; |
| 207 | const int code = icmp_hdr(skb)->code; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 208 | struct sock *sk; |
| 209 | __u64 seq; |
| 210 | int err; |
Pavel Emelyanov | fd54d71 | 2008-07-14 23:01:40 -0700 | [diff] [blame] | 211 | struct net *net = dev_net(skb->dev); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 212 | |
Wei Yongjun | 18e1d83 | 2008-07-26 11:59:10 +0100 | [diff] [blame] | 213 | if (skb->len < offset + sizeof(*dh) || |
| 214 | skb->len < offset + __dccp_basic_hdr_len(dh)) { |
Pavel Emelyanov | dcfc23c | 2008-07-14 23:03:00 -0700 | [diff] [blame] | 215 | ICMP_INC_STATS_BH(net, ICMP_MIB_INERRORS); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 216 | return; |
| 217 | } |
| 218 | |
Pavel Emelyanov | fd54d71 | 2008-07-14 23:01:40 -0700 | [diff] [blame] | 219 | sk = inet_lookup(net, &dccp_hashinfo, |
Pavel Emelyanov | b9901a8 | 2008-04-13 22:30:43 -0700 | [diff] [blame] | 220 | iph->daddr, dh->dccph_dport, |
| 221 | iph->saddr, dh->dccph_sport, inet_iif(skb)); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 222 | if (sk == NULL) { |
Pavel Emelyanov | dcfc23c | 2008-07-14 23:03:00 -0700 | [diff] [blame] | 223 | ICMP_INC_STATS_BH(net, ICMP_MIB_INERRORS); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 224 | return; |
| 225 | } |
| 226 | |
| 227 | if (sk->sk_state == DCCP_TIME_WAIT) { |
YOSHIFUJI Hideaki | 9469c7b | 2006-10-10 19:41:46 -0700 | [diff] [blame] | 228 | inet_twsk_put(inet_twsk(sk)); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 229 | return; |
| 230 | } |
| 231 | |
| 232 | bh_lock_sock(sk); |
| 233 | /* If too many ICMPs get dropped on busy |
| 234 | * servers this needs to be solved differently. |
| 235 | */ |
| 236 | if (sock_owned_by_user(sk)) |
Pavel Emelyanov | de0744a | 2008-07-16 20:31:16 -0700 | [diff] [blame] | 237 | NET_INC_STATS_BH(net, LINUX_MIB_LOCKDROPPEDICMPS); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 238 | |
| 239 | if (sk->sk_state == DCCP_CLOSED) |
| 240 | goto out; |
| 241 | |
| 242 | dp = dccp_sk(sk); |
Gerrit Renker | fde2010 | 2007-10-24 10:12:09 -0200 | [diff] [blame] | 243 | seq = dccp_hdr_seq(dh); |
Gerrit Renker | 1238d08 | 2007-10-24 10:18:06 -0200 | [diff] [blame] | 244 | if ((1 << sk->sk_state) & ~(DCCPF_REQUESTING | DCCPF_LISTEN) && |
Wei Yongjun | d68f086 | 2008-07-26 11:59:10 +0100 | [diff] [blame] | 245 | !between48(seq, dp->dccps_awl, dp->dccps_awh)) { |
Pavel Emelyanov | de0744a | 2008-07-16 20:31:16 -0700 | [diff] [blame] | 246 | NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 247 | goto out; |
| 248 | } |
| 249 | |
| 250 | switch (type) { |
| 251 | case ICMP_SOURCE_QUENCH: |
| 252 | /* Just silently ignore these. */ |
| 253 | goto out; |
| 254 | case ICMP_PARAMETERPROB: |
| 255 | err = EPROTO; |
| 256 | break; |
| 257 | case ICMP_DEST_UNREACH: |
| 258 | if (code > NR_ICMP_UNREACH) |
| 259 | goto out; |
| 260 | |
| 261 | if (code == ICMP_FRAG_NEEDED) { /* PMTU discovery (RFC1191) */ |
| 262 | if (!sock_owned_by_user(sk)) |
| 263 | dccp_do_pmtu_discovery(sk, iph, info); |
| 264 | goto out; |
| 265 | } |
| 266 | |
| 267 | err = icmp_err_convert[code].errno; |
| 268 | break; |
| 269 | case ICMP_TIME_EXCEEDED: |
| 270 | err = EHOSTUNREACH; |
| 271 | break; |
| 272 | default: |
| 273 | goto out; |
| 274 | } |
| 275 | |
| 276 | switch (sk->sk_state) { |
| 277 | struct request_sock *req , **prev; |
| 278 | case DCCP_LISTEN: |
| 279 | if (sock_owned_by_user(sk)) |
| 280 | goto out; |
| 281 | req = inet_csk_search_req(sk, &prev, dh->dccph_dport, |
| 282 | iph->daddr, iph->saddr); |
| 283 | if (!req) |
| 284 | goto out; |
| 285 | |
| 286 | /* |
| 287 | * ICMPs are not backlogged, hence we cannot get an established |
| 288 | * socket here. |
| 289 | */ |
Ilpo Järvinen | 547b792 | 2008-07-25 21:43:18 -0700 | [diff] [blame] | 290 | WARN_ON(req->sk); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 291 | |
| 292 | if (seq != dccp_rsk(req)->dreq_iss) { |
Pavel Emelyanov | de0744a | 2008-07-16 20:31:16 -0700 | [diff] [blame] | 293 | NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 294 | goto out; |
| 295 | } |
| 296 | /* |
| 297 | * Still in RESPOND, just remove it silently. |
| 298 | * There is no good way to pass the error to the newly |
| 299 | * created socket, and POSIX does not want network |
| 300 | * errors returned from accept(). |
| 301 | */ |
| 302 | inet_csk_reqsk_queue_drop(sk, req, prev); |
| 303 | goto out; |
| 304 | |
| 305 | case DCCP_REQUESTING: |
| 306 | case DCCP_RESPOND: |
| 307 | if (!sock_owned_by_user(sk)) { |
| 308 | DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS); |
| 309 | sk->sk_err = err; |
| 310 | |
| 311 | sk->sk_error_report(sk); |
| 312 | |
| 313 | dccp_done(sk); |
| 314 | } else |
| 315 | sk->sk_err_soft = err; |
| 316 | goto out; |
| 317 | } |
| 318 | |
| 319 | /* If we've already connected we will keep trying |
| 320 | * until we time out, or the user gives up. |
| 321 | * |
| 322 | * rfc1122 4.2.3.9 allows to consider as hard errors |
| 323 | * only PROTO_UNREACH and PORT_UNREACH (well, FRAG_FAILED too, |
| 324 | * but it is obsoleted by pmtu discovery). |
| 325 | * |
| 326 | * Note, that in modern internet, where routing is unreliable |
| 327 | * and in each dark corner broken firewalls sit, sending random |
| 328 | * errors ordered by their masters even this two messages finally lose |
| 329 | * their original sense (even Linux sends invalid PORT_UNREACHs) |
| 330 | * |
| 331 | * Now we are in compliance with RFCs. |
| 332 | * --ANK (980905) |
| 333 | */ |
| 334 | |
| 335 | inet = inet_sk(sk); |
| 336 | if (!sock_owned_by_user(sk) && inet->recverr) { |
| 337 | sk->sk_err = err; |
| 338 | sk->sk_error_report(sk); |
| 339 | } else /* Only an error on timeout */ |
| 340 | sk->sk_err_soft = err; |
| 341 | out: |
| 342 | bh_unlock_sock(sk); |
| 343 | sock_put(sk); |
| 344 | } |
| 345 | |
Al Viro | 2bda285 | 2006-11-14 21:28:51 -0800 | [diff] [blame] | 346 | static inline __sum16 dccp_v4_csum_finish(struct sk_buff *skb, |
Gerrit Renker | 6f4e5ff | 2006-11-10 17:43:06 -0200 | [diff] [blame] | 347 | __be32 src, __be32 dst) |
| 348 | { |
| 349 | return csum_tcpudp_magic(src, dst, skb->len, IPPROTO_DCCP, skb->csum); |
| 350 | } |
| 351 | |
| 352 | void dccp_v4_send_check(struct sock *sk, int unused, struct sk_buff *skb) |
Arnaldo Carvalho de Melo | 57cca05 | 2005-12-13 23:16:16 -0800 | [diff] [blame] | 353 | { |
| 354 | const struct inet_sock *inet = inet_sk(sk); |
| 355 | struct dccp_hdr *dh = dccp_hdr(skb); |
| 356 | |
Gerrit Renker | 6f4e5ff | 2006-11-10 17:43:06 -0200 | [diff] [blame] | 357 | dccp_csum_outgoing(skb); |
Eric Dumazet | c720c7e | 2009-10-15 06:30:45 +0000 | [diff] [blame] | 358 | dh->dccph_checksum = dccp_v4_csum_finish(skb, |
| 359 | inet->inet_saddr, |
| 360 | inet->inet_daddr); |
Arnaldo Carvalho de Melo | 57cca05 | 2005-12-13 23:16:16 -0800 | [diff] [blame] | 361 | } |
| 362 | |
Arnaldo Carvalho de Melo | f21e68c | 2005-12-13 23:24:16 -0800 | [diff] [blame] | 363 | EXPORT_SYMBOL_GPL(dccp_v4_send_check); |
| 364 | |
Gerrit Renker | 865e902 | 2006-11-13 13:31:50 -0200 | [diff] [blame] | 365 | 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] | 366 | { |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 367 | return secure_dccp_sequence_number(ip_hdr(skb)->daddr, |
| 368 | ip_hdr(skb)->saddr, |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 369 | dccp_hdr(skb)->dccph_dport, |
| 370 | dccp_hdr(skb)->dccph_sport); |
| 371 | } |
| 372 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 373 | /* |
| 374 | * The three way handshake has completed - we got a valid ACK or DATAACK - |
| 375 | * now create the new socket. |
| 376 | * |
| 377 | * This is the equivalent of TCP's tcp_v4_syn_recv_sock |
| 378 | */ |
| 379 | struct sock *dccp_v4_request_recv_sock(struct sock *sk, struct sk_buff *skb, |
| 380 | struct request_sock *req, |
| 381 | struct dst_entry *dst) |
| 382 | { |
| 383 | struct inet_request_sock *ireq; |
| 384 | struct inet_sock *newinet; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 385 | struct sock *newsk; |
| 386 | |
| 387 | if (sk_acceptq_is_full(sk)) |
| 388 | goto exit_overflow; |
| 389 | |
| 390 | if (dst == NULL && (dst = inet_csk_route_req(sk, req)) == NULL) |
| 391 | goto exit; |
| 392 | |
| 393 | newsk = dccp_create_openreq_child(sk, req, skb); |
| 394 | if (newsk == NULL) |
| 395 | goto exit; |
| 396 | |
| 397 | sk_setup_caps(newsk, dst); |
| 398 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 399 | newinet = inet_sk(newsk); |
| 400 | ireq = inet_rsk(req); |
Eric Dumazet | c720c7e | 2009-10-15 06:30:45 +0000 | [diff] [blame] | 401 | newinet->inet_daddr = ireq->rmt_addr; |
| 402 | newinet->inet_rcv_saddr = ireq->loc_addr; |
| 403 | newinet->inet_saddr = ireq->loc_addr; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 404 | newinet->opt = ireq->opt; |
| 405 | ireq->opt = NULL; |
| 406 | newinet->mc_index = inet_iif(skb); |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 407 | newinet->mc_ttl = ip_hdr(skb)->ttl; |
Eric Dumazet | c720c7e | 2009-10-15 06:30:45 +0000 | [diff] [blame] | 408 | newinet->inet_id = jiffies; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 409 | |
| 410 | dccp_sync_mss(newsk, dst_mtu(dst)); |
| 411 | |
Eric Dumazet | 9327f70 | 2009-12-04 03:46:54 +0000 | [diff] [blame] | 412 | __inet_hash_nolisten(newsk, NULL); |
Arnaldo Carvalho de Melo | ab1e0a1 | 2008-02-03 04:06:04 -0800 | [diff] [blame] | 413 | __inet_inherit_port(sk, newsk); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 414 | |
| 415 | return newsk; |
| 416 | |
| 417 | exit_overflow: |
Pavel Emelyanov | de0744a | 2008-07-16 20:31:16 -0700 | [diff] [blame] | 418 | NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 419 | exit: |
Pavel Emelyanov | de0744a | 2008-07-16 20:31:16 -0700 | [diff] [blame] | 420 | NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 421 | dst_release(dst); |
| 422 | return NULL; |
| 423 | } |
| 424 | |
Arnaldo Carvalho de Melo | f21e68c | 2005-12-13 23:24:16 -0800 | [diff] [blame] | 425 | EXPORT_SYMBOL_GPL(dccp_v4_request_recv_sock); |
| 426 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 427 | static struct sock *dccp_v4_hnd_req(struct sock *sk, struct sk_buff *skb) |
| 428 | { |
| 429 | const struct dccp_hdr *dh = dccp_hdr(skb); |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 430 | const struct iphdr *iph = ip_hdr(skb); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 431 | struct sock *nsk; |
| 432 | struct request_sock **prev; |
| 433 | /* Find possible connection requests. */ |
| 434 | struct request_sock *req = inet_csk_search_req(sk, &prev, |
| 435 | dh->dccph_sport, |
| 436 | iph->saddr, iph->daddr); |
| 437 | if (req != NULL) |
| 438 | return dccp_check_req(sk, skb, req, prev); |
| 439 | |
Pavel Emelyanov | b9901a8 | 2008-04-13 22:30:43 -0700 | [diff] [blame] | 440 | nsk = inet_lookup_established(sock_net(sk), &dccp_hashinfo, |
Herbert Xu | 8f491069 | 2006-08-09 15:47:12 -0700 | [diff] [blame] | 441 | iph->saddr, dh->dccph_sport, |
| 442 | iph->daddr, dh->dccph_dport, |
| 443 | inet_iif(skb)); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 444 | if (nsk != NULL) { |
| 445 | if (nsk->sk_state != DCCP_TIME_WAIT) { |
| 446 | bh_lock_sock(nsk); |
| 447 | return nsk; |
| 448 | } |
YOSHIFUJI Hideaki | 9469c7b | 2006-10-10 19:41:46 -0700 | [diff] [blame] | 449 | inet_twsk_put(inet_twsk(nsk)); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 450 | return NULL; |
| 451 | } |
| 452 | |
| 453 | return sk; |
| 454 | } |
| 455 | |
Pavel Emelyanov | f548739 | 2008-04-13 22:30:19 -0700 | [diff] [blame] | 456 | 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] | 457 | struct sk_buff *skb) |
| 458 | { |
| 459 | struct rtable *rt; |
Eric Dumazet | 511c3f9 | 2009-06-02 05:14:27 +0000 | [diff] [blame] | 460 | struct flowi fl = { .oif = skb_rtable(skb)->rt_iif, |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 461 | .nl_u = { .ip4_u = |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 462 | { .daddr = ip_hdr(skb)->saddr, |
| 463 | .saddr = ip_hdr(skb)->daddr, |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 464 | .tos = RT_CONN_FLAGS(sk) } }, |
| 465 | .proto = sk->sk_protocol, |
| 466 | .uli_u = { .ports = |
| 467 | { .sport = dccp_hdr(skb)->dccph_dport, |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 468 | .dport = dccp_hdr(skb)->dccph_sport } |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 469 | } |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 470 | }; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 471 | |
Venkat Yekkirala | beb8d13 | 2006-08-04 23:12:42 -0700 | [diff] [blame] | 472 | security_skb_classify_flow(skb, &fl); |
Pavel Emelyanov | f548739 | 2008-04-13 22:30:19 -0700 | [diff] [blame] | 473 | if (ip_route_output_flow(net, &rt, &fl, sk, 0)) { |
Pavel Emelyanov | 7c73a6f | 2008-07-16 20:20:11 -0700 | [diff] [blame] | 474 | IP_INC_STATS_BH(net, IPSTATS_MIB_OUTNOROUTES); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 475 | return NULL; |
| 476 | } |
| 477 | |
| 478 | return &rt->u.dst; |
| 479 | } |
| 480 | |
William Allen Simpson | e6b4d11 | 2009-12-02 18:07:39 +0000 | [diff] [blame] | 481 | static int dccp_v4_send_response(struct sock *sk, struct request_sock *req, |
| 482 | struct request_values *rv_unused) |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 483 | { |
| 484 | int err = -1; |
| 485 | struct sk_buff *skb; |
Denis V. Lunev | fd80eb9 | 2008-02-29 11:43:03 -0800 | [diff] [blame] | 486 | struct dst_entry *dst; |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 487 | |
Denis V. Lunev | fd80eb9 | 2008-02-29 11:43:03 -0800 | [diff] [blame] | 488 | dst = inet_csk_route_req(sk, req); |
| 489 | if (dst == NULL) |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 490 | goto out; |
| 491 | |
| 492 | skb = dccp_make_response(sk, dst, req); |
| 493 | if (skb != NULL) { |
| 494 | const struct inet_request_sock *ireq = inet_rsk(req); |
| 495 | struct dccp_hdr *dh = dccp_hdr(skb); |
| 496 | |
Gerrit Renker | 6f4e5ff | 2006-11-10 17:43:06 -0200 | [diff] [blame] | 497 | dh->dccph_checksum = dccp_v4_csum_finish(skb, ireq->loc_addr, |
| 498 | ireq->rmt_addr); |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 499 | err = ip_build_and_send_pkt(skb, sk, ireq->loc_addr, |
| 500 | ireq->rmt_addr, |
| 501 | ireq->opt); |
Gerrit Renker | b9df3cb | 2006-11-14 11:21:36 -0200 | [diff] [blame] | 502 | err = net_xmit_eval(err); |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 503 | } |
| 504 | |
| 505 | out: |
| 506 | dst_release(dst); |
| 507 | return err; |
| 508 | } |
| 509 | |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 510 | 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] | 511 | { |
| 512 | int err; |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 513 | const struct iphdr *rxiph; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 514 | struct sk_buff *skb; |
| 515 | struct dst_entry *dst; |
Eric Dumazet | adf3090 | 2009-06-02 05:19:30 +0000 | [diff] [blame] | 516 | struct net *net = dev_net(skb_dst(rxskb)->dev); |
Pavel Emelyanov | b76c4b2 | 2008-04-13 22:29:59 -0700 | [diff] [blame] | 517 | struct sock *ctl_sk = net->dccp.v4_ctl_sk; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 518 | |
| 519 | /* Never send a reset in response to a reset. */ |
Gerrit Renker | e356d37 | 2007-09-26 14:35:19 -0300 | [diff] [blame] | 520 | if (dccp_hdr(rxskb)->dccph_type == DCCP_PKT_RESET) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 521 | return; |
| 522 | |
Eric Dumazet | 511c3f9 | 2009-06-02 05:14:27 +0000 | [diff] [blame] | 523 | if (skb_rtable(rxskb)->rt_type != RTN_LOCAL) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 524 | return; |
| 525 | |
Pavel Emelyanov | f548739 | 2008-04-13 22:30:19 -0700 | [diff] [blame] | 526 | dst = dccp_v4_route_skb(net, ctl_sk, rxskb); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 527 | if (dst == NULL) |
| 528 | return; |
| 529 | |
Pavel Emelyanov | 7b1cffa | 2008-04-13 22:29:37 -0700 | [diff] [blame] | 530 | skb = dccp_ctl_make_reset(ctl_sk, rxskb); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 531 | if (skb == NULL) |
| 532 | goto out; |
| 533 | |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 534 | rxiph = ip_hdr(rxskb); |
Gerrit Renker | e356d37 | 2007-09-26 14:35:19 -0300 | [diff] [blame] | 535 | dccp_hdr(skb)->dccph_checksum = dccp_v4_csum_finish(skb, rxiph->saddr, |
| 536 | rxiph->daddr); |
Eric Dumazet | adf3090 | 2009-06-02 05:19:30 +0000 | [diff] [blame] | 537 | skb_dst_set(skb, dst_clone(dst)); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 538 | |
Pavel Emelyanov | 7b1cffa | 2008-04-13 22:29:37 -0700 | [diff] [blame] | 539 | bh_lock_sock(ctl_sk); |
| 540 | err = ip_build_and_send_pkt(skb, ctl_sk, |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 541 | rxiph->daddr, rxiph->saddr, NULL); |
Pavel Emelyanov | 7b1cffa | 2008-04-13 22:29:37 -0700 | [diff] [blame] | 542 | bh_unlock_sock(ctl_sk); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 543 | |
Gerrit Renker | b9df3cb | 2006-11-14 11:21:36 -0200 | [diff] [blame] | 544 | if (net_xmit_eval(err) == 0) { |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 545 | DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS); |
| 546 | DCCP_INC_STATS_BH(DCCP_MIB_OUTRSTS); |
| 547 | } |
| 548 | out: |
| 549 | dst_release(dst); |
| 550 | } |
| 551 | |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 552 | static void dccp_v4_reqsk_destructor(struct request_sock *req) |
| 553 | { |
Gerrit Renker | d99a7bd | 2008-11-04 23:56:30 -0800 | [diff] [blame] | 554 | dccp_feat_list_purge(&dccp_rsk(req)->dreq_featneg); |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 555 | kfree(inet_rsk(req)->opt); |
| 556 | } |
| 557 | |
| 558 | static struct request_sock_ops dccp_request_sock_ops __read_mostly = { |
| 559 | .family = PF_INET, |
| 560 | .obj_size = sizeof(struct dccp_request_sock), |
| 561 | .rtx_syn_ack = dccp_v4_send_response, |
| 562 | .send_ack = dccp_reqsk_send_ack, |
| 563 | .destructor = dccp_v4_reqsk_destructor, |
| 564 | .send_reset = dccp_v4_ctl_send_reset, |
| 565 | }; |
| 566 | |
| 567 | int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb) |
| 568 | { |
| 569 | struct inet_request_sock *ireq; |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 570 | struct request_sock *req; |
| 571 | struct dccp_request_sock *dreq; |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 572 | const __be32 service = dccp_hdr_request(skb)->dccph_req_service; |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 573 | struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb); |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 574 | |
| 575 | /* Never answer to DCCP_PKT_REQUESTs send to broadcast or multicast */ |
Eric Dumazet | 511c3f9 | 2009-06-02 05:14:27 +0000 | [diff] [blame] | 576 | if (skb_rtable(skb)->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) |
Gerrit Renker | 4a5409a | 2007-10-04 14:52:28 -0700 | [diff] [blame] | 577 | return 0; /* discard, don't send a reset here */ |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 578 | |
| 579 | if (dccp_bad_service_code(sk, service)) { |
Gerrit Renker | 4a5409a | 2007-10-04 14:52:28 -0700 | [diff] [blame] | 580 | dcb->dccpd_reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE; |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 581 | goto drop; |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 582 | } |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 583 | /* |
| 584 | * TW buckets are converted to open requests without |
| 585 | * limitations, they conserve resources and peer is |
| 586 | * evidently real one. |
| 587 | */ |
Gerrit Renker | 4a5409a | 2007-10-04 14:52:28 -0700 | [diff] [blame] | 588 | dcb->dccpd_reset_code = DCCP_RESET_CODE_TOO_BUSY; |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 589 | if (inet_csk_reqsk_queue_is_full(sk)) |
| 590 | goto drop; |
| 591 | |
| 592 | /* |
| 593 | * Accept backlog is full. If we have already queued enough |
| 594 | * of warm entries in syn queue, drop request. It is better than |
| 595 | * clogging syn queue with openreqs with exponentially increasing |
| 596 | * timeout. |
| 597 | */ |
| 598 | if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1) |
| 599 | goto drop; |
| 600 | |
Arnaldo Carvalho de Melo | ce4a7d0 | 2008-06-10 12:39:35 -0700 | [diff] [blame] | 601 | req = inet_reqsk_alloc(&dccp_request_sock_ops); |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 602 | if (req == NULL) |
| 603 | goto drop; |
| 604 | |
Gerrit Renker | ac75773 | 2008-11-04 23:55:49 -0800 | [diff] [blame] | 605 | if (dccp_reqsk_init(req, dccp_sk(sk), skb)) |
| 606 | goto drop_and_free; |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 607 | |
Gerrit Renker | 8b81941 | 2007-12-13 12:29:24 -0200 | [diff] [blame] | 608 | dreq = dccp_rsk(req); |
| 609 | if (dccp_parse_options(sk, dreq, skb)) |
| 610 | goto drop_and_free; |
| 611 | |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 612 | if (security_inet_conn_request(sk, skb, req)) |
| 613 | goto drop_and_free; |
| 614 | |
| 615 | ireq = inet_rsk(req); |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 616 | ireq->loc_addr = ip_hdr(skb)->daddr; |
| 617 | ireq->rmt_addr = ip_hdr(skb)->saddr; |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 618 | |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 619 | /* |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 620 | * Step 3: Process LISTEN state |
| 621 | * |
| 622 | * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie |
| 623 | * |
| 624 | * In fact we defer setting S.GSR, S.SWL, S.SWH to |
| 625 | * dccp_create_openreq_child. |
| 626 | */ |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 627 | dreq->dreq_isr = dcb->dccpd_seq; |
Gerrit Renker | 865e902 | 2006-11-13 13:31:50 -0200 | [diff] [blame] | 628 | dreq->dreq_iss = dccp_v4_init_sequence(skb); |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 629 | dreq->dreq_service = service; |
| 630 | |
William Allen Simpson | e6b4d11 | 2009-12-02 18:07:39 +0000 | [diff] [blame] | 631 | if (dccp_v4_send_response(sk, req, NULL)) |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 632 | goto drop_and_free; |
| 633 | |
| 634 | inet_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT); |
| 635 | return 0; |
| 636 | |
| 637 | drop_and_free: |
| 638 | reqsk_free(req); |
| 639 | drop: |
| 640 | DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS); |
Gerrit Renker | 3d2fe62 | 2006-11-10 12:52:36 -0200 | [diff] [blame] | 641 | return -1; |
| 642 | } |
| 643 | |
| 644 | EXPORT_SYMBOL_GPL(dccp_v4_conn_request); |
| 645 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 646 | int dccp_v4_do_rcv(struct sock *sk, struct sk_buff *skb) |
| 647 | { |
| 648 | struct dccp_hdr *dh = dccp_hdr(skb); |
| 649 | |
| 650 | if (sk->sk_state == DCCP_OPEN) { /* Fast path */ |
| 651 | if (dccp_rcv_established(sk, skb, dh, skb->len)) |
| 652 | goto reset; |
| 653 | return 0; |
| 654 | } |
| 655 | |
| 656 | /* |
| 657 | * Step 3: Process LISTEN state |
Gerrit Renker | d83ca5a | 2006-11-10 16:29:14 -0200 | [diff] [blame] | 658 | * If P.type == Request or P contains a valid Init Cookie option, |
| 659 | * (* Must scan the packet's options to check for Init |
| 660 | * Cookies. Only Init Cookies are processed here, |
| 661 | * however; other options are processed in Step 8. This |
| 662 | * scan need only be performed if the endpoint uses Init |
| 663 | * Cookies *) |
| 664 | * (* Generate a new socket and switch to that socket *) |
| 665 | * Set S := new socket for this port pair |
| 666 | * S.state = RESPOND |
| 667 | * Choose S.ISS (initial seqno) or set from Init Cookies |
| 668 | * Initialize S.GAR := S.ISS |
| 669 | * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookies |
| 670 | * Continue with S.state == RESPOND |
| 671 | * (* A Response packet will be generated in Step 11 *) |
| 672 | * Otherwise, |
| 673 | * Generate Reset(No Connection) unless P.type == Reset |
| 674 | * Drop packet and return |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 675 | * |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 676 | * NOTE: the check for the packet types is done in |
| 677 | * dccp_rcv_state_process |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 678 | */ |
| 679 | if (sk->sk_state == DCCP_LISTEN) { |
| 680 | struct sock *nsk = dccp_v4_hnd_req(sk, skb); |
| 681 | |
| 682 | if (nsk == NULL) |
| 683 | goto discard; |
| 684 | |
| 685 | if (nsk != sk) { |
| 686 | if (dccp_child_process(sk, nsk, skb)) |
| 687 | goto reset; |
| 688 | return 0; |
| 689 | } |
| 690 | } |
| 691 | |
| 692 | if (dccp_rcv_state_process(sk, skb, dh, skb->len)) |
| 693 | goto reset; |
| 694 | return 0; |
| 695 | |
| 696 | reset: |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 697 | dccp_v4_ctl_send_reset(sk, skb); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 698 | discard: |
| 699 | kfree_skb(skb); |
| 700 | return 0; |
| 701 | } |
| 702 | |
Arnaldo Carvalho de Melo | f21e68c | 2005-12-13 23:24:16 -0800 | [diff] [blame] | 703 | EXPORT_SYMBOL_GPL(dccp_v4_do_rcv); |
| 704 | |
Gerrit Renker | 09dbc38 | 2006-11-14 12:57:34 -0200 | [diff] [blame] | 705 | /** |
| 706 | * dccp_invalid_packet - check for malformed packets |
| 707 | * Implements RFC 4340, 8.5: Step 1: Check header basics |
| 708 | * Packets that fail these checks are ignored and do not receive Resets. |
| 709 | */ |
Arnaldo Carvalho de Melo | f21e68c | 2005-12-13 23:24:16 -0800 | [diff] [blame] | 710 | int dccp_invalid_packet(struct sk_buff *skb) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 711 | { |
| 712 | const struct dccp_hdr *dh; |
Gerrit Renker | 6f4e5ff | 2006-11-10 17:43:06 -0200 | [diff] [blame] | 713 | unsigned int cscov; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 714 | |
| 715 | if (skb->pkt_type != PACKET_HOST) |
| 716 | return 1; |
| 717 | |
Gerrit Renker | 09dbc38 | 2006-11-14 12:57:34 -0200 | [diff] [blame] | 718 | /* 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] | 719 | if (!pskb_may_pull(skb, sizeof(struct dccp_hdr))) { |
Gerrit Renker | 59348b1 | 2006-11-20 18:39:23 -0200 | [diff] [blame] | 720 | DCCP_WARN("pskb_may_pull failed\n"); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 721 | return 1; |
| 722 | } |
| 723 | |
| 724 | dh = dccp_hdr(skb); |
| 725 | |
Gerrit Renker | 09dbc38 | 2006-11-14 12:57:34 -0200 | [diff] [blame] | 726 | /* If P.type is not understood, drop packet and return */ |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 727 | if (dh->dccph_type >= DCCP_PKT_INVALID) { |
Gerrit Renker | 59348b1 | 2006-11-20 18:39:23 -0200 | [diff] [blame] | 728 | DCCP_WARN("invalid packet type\n"); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 729 | return 1; |
| 730 | } |
| 731 | |
| 732 | /* |
Gerrit Renker | 09dbc38 | 2006-11-14 12:57:34 -0200 | [diff] [blame] | 733 | * 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] | 734 | */ |
| 735 | if (dh->dccph_doff < dccp_hdr_len(skb) / sizeof(u32)) { |
Gerrit Renker | 59348b1 | 2006-11-20 18:39:23 -0200 | [diff] [blame] | 736 | 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] | 737 | return 1; |
| 738 | } |
Gerrit Renker | 09dbc38 | 2006-11-14 12:57:34 -0200 | [diff] [blame] | 739 | /* |
| 740 | * If P.Data Offset is too too large for packet, drop packet and return |
| 741 | */ |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 742 | if (!pskb_may_pull(skb, dh->dccph_doff * sizeof(u32))) { |
Gerrit Renker | 59348b1 | 2006-11-20 18:39:23 -0200 | [diff] [blame] | 743 | 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] | 744 | return 1; |
| 745 | } |
| 746 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 747 | /* |
| 748 | * If P.type is not Data, Ack, or DataAck and P.X == 0 (the packet |
| 749 | * has short sequence numbers), drop packet and return |
| 750 | */ |
Wei Yongjun | 6079a46 | 2008-05-27 06:22:38 -0700 | [diff] [blame] | 751 | if ((dh->dccph_type < DCCP_PKT_DATA || |
| 752 | dh->dccph_type > DCCP_PKT_DATAACK) && dh->dccph_x == 0) { |
Gerrit Renker | 59348b1 | 2006-11-20 18:39:23 -0200 | [diff] [blame] | 753 | DCCP_WARN("P.type (%s) not Data || [Data]Ack, while P.X == 0\n", |
| 754 | dccp_packet_name(dh->dccph_type)); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 755 | return 1; |
| 756 | } |
| 757 | |
Gerrit Renker | 6f4e5ff | 2006-11-10 17:43:06 -0200 | [diff] [blame] | 758 | /* |
| 759 | * If P.CsCov is too large for the packet size, drop packet and return. |
| 760 | * This must come _before_ checksumming (not as RFC 4340 suggests). |
| 761 | */ |
| 762 | cscov = dccp_csum_coverage(skb); |
| 763 | if (cscov > skb->len) { |
Gerrit Renker | 59348b1 | 2006-11-20 18:39:23 -0200 | [diff] [blame] | 764 | DCCP_WARN("P.CsCov %u exceeds packet length %d\n", |
| 765 | dh->dccph_cscov, skb->len); |
Gerrit Renker | 6f4e5ff | 2006-11-10 17:43:06 -0200 | [diff] [blame] | 766 | return 1; |
| 767 | } |
| 768 | |
| 769 | /* If header checksum is incorrect, drop packet and return. |
| 770 | * (This step is completed in the AF-dependent functions.) */ |
| 771 | skb->csum = skb_checksum(skb, 0, cscov, 0); |
| 772 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 773 | return 0; |
| 774 | } |
| 775 | |
Arnaldo Carvalho de Melo | f21e68c | 2005-12-13 23:24:16 -0800 | [diff] [blame] | 776 | EXPORT_SYMBOL_GPL(dccp_invalid_packet); |
| 777 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 778 | /* this is called when real data arrives */ |
Arnaldo Carvalho de Melo | b61fafc | 2006-03-20 21:25:11 -0800 | [diff] [blame] | 779 | static int dccp_v4_rcv(struct sk_buff *skb) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 780 | { |
| 781 | const struct dccp_hdr *dh; |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 782 | const struct iphdr *iph; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 783 | struct sock *sk; |
Gerrit Renker | 6f4e5ff | 2006-11-10 17:43:06 -0200 | [diff] [blame] | 784 | int min_cov; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 785 | |
Gerrit Renker | 6f4e5ff | 2006-11-10 17:43:06 -0200 | [diff] [blame] | 786 | /* Step 1: Check header basics */ |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 787 | |
| 788 | if (dccp_invalid_packet(skb)) |
| 789 | goto discard_it; |
| 790 | |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 791 | iph = ip_hdr(skb); |
Gerrit Renker | 6f4e5ff | 2006-11-10 17:43:06 -0200 | [diff] [blame] | 792 | /* 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] | 793 | if (dccp_v4_csum_finish(skb, iph->saddr, iph->daddr)) { |
Gerrit Renker | 59348b1 | 2006-11-20 18:39:23 -0200 | [diff] [blame] | 794 | DCCP_WARN("dropped packet with invalid checksum\n"); |
Arnaldo Carvalho de Melo | f21e68c | 2005-12-13 23:24:16 -0800 | [diff] [blame] | 795 | goto discard_it; |
| 796 | } |
| 797 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 798 | dh = dccp_hdr(skb); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 799 | |
Gerrit Renker | fde2010 | 2007-10-24 10:12:09 -0200 | [diff] [blame] | 800 | DCCP_SKB_CB(skb)->dccpd_seq = dccp_hdr_seq(dh); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 801 | DCCP_SKB_CB(skb)->dccpd_type = dh->dccph_type; |
| 802 | |
Harvey Harrison | 21454aa | 2008-10-31 00:54:56 -0700 | [diff] [blame] | 803 | 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] | 804 | dccp_packet_name(dh->dccph_type), |
Harvey Harrison | 21454aa | 2008-10-31 00:54:56 -0700 | [diff] [blame] | 805 | &iph->saddr, ntohs(dh->dccph_sport), |
| 806 | &iph->daddr, ntohs(dh->dccph_dport), |
David S. Miller | f6ccf55 | 2005-08-09 20:27:14 -0700 | [diff] [blame] | 807 | (unsigned long long) DCCP_SKB_CB(skb)->dccpd_seq); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 808 | |
| 809 | if (dccp_packet_without_ack(skb)) { |
| 810 | DCCP_SKB_CB(skb)->dccpd_ack_seq = DCCP_PKT_WITHOUT_ACK_SEQ; |
| 811 | dccp_pr_debug_cat("\n"); |
| 812 | } else { |
| 813 | DCCP_SKB_CB(skb)->dccpd_ack_seq = dccp_hdr_ack_seq(skb); |
Gerrit Renker | d23c710 | 2006-11-10 11:46:34 -0200 | [diff] [blame] | 814 | dccp_pr_debug_cat(", ack=%llu\n", (unsigned long long) |
David S. Miller | f6ccf55 | 2005-08-09 20:27:14 -0700 | [diff] [blame] | 815 | DCCP_SKB_CB(skb)->dccpd_ack_seq); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 816 | } |
| 817 | |
| 818 | /* Step 2: |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 819 | * Look up flow ID in table and get corresponding socket */ |
Arnaldo Carvalho de Melo | 9a1f27c | 2008-10-07 11:41:57 -0700 | [diff] [blame] | 820 | sk = __inet_lookup_skb(&dccp_hashinfo, skb, |
| 821 | dh->dccph_sport, dh->dccph_dport); |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 822 | /* |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 823 | * Step 2: |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 824 | * If no socket ... |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 825 | */ |
| 826 | if (sk == NULL) { |
| 827 | dccp_pr_debug("failed to look up flow ID in table and " |
| 828 | "get corresponding socket\n"); |
| 829 | goto no_dccp_socket; |
| 830 | } |
| 831 | |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 832 | /* |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 833 | * Step 2: |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 834 | * ... or S.state == TIMEWAIT, |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 835 | * Generate Reset(No Connection) unless P.type == Reset |
| 836 | * Drop packet and return |
| 837 | */ |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 838 | if (sk->sk_state == DCCP_TIME_WAIT) { |
Gerrit Renker | d23c710 | 2006-11-10 11:46:34 -0200 | [diff] [blame] | 839 | dccp_pr_debug("sk->sk_state == DCCP_TIME_WAIT: do_time_wait\n"); |
| 840 | inet_twsk_put(inet_twsk(sk)); |
| 841 | goto no_dccp_socket; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 842 | } |
| 843 | |
Gerrit Renker | 6f4e5ff | 2006-11-10 17:43:06 -0200 | [diff] [blame] | 844 | /* |
| 845 | * RFC 4340, sec. 9.2.1: Minimum Checksum Coverage |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 846 | * o if MinCsCov = 0, only packets with CsCov = 0 are accepted |
| 847 | * o if MinCsCov > 0, also accept packets with CsCov >= MinCsCov |
Gerrit Renker | 6f4e5ff | 2006-11-10 17:43:06 -0200 | [diff] [blame] | 848 | */ |
| 849 | min_cov = dccp_sk(sk)->dccps_pcrlen; |
| 850 | if (dh->dccph_cscov && (min_cov == 0 || dh->dccph_cscov < min_cov)) { |
| 851 | dccp_pr_debug("Packet CsCov %d does not satisfy MinCsCov %d\n", |
| 852 | dh->dccph_cscov, min_cov); |
| 853 | /* FIXME: "Such packets SHOULD be reported using Data Dropped |
| 854 | * options (Section 11.7) with Drop Code 0, Protocol |
| 855 | * Constraints." */ |
| 856 | goto discard_and_relse; |
| 857 | } |
| 858 | |
Arnaldo Carvalho de Melo | 25995ff | 2005-12-27 02:42:22 -0200 | [diff] [blame] | 859 | if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 860 | goto discard_and_relse; |
Patrick McHardy | eb9c7eb | 2006-01-06 23:06:30 -0800 | [diff] [blame] | 861 | nf_reset(skb); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 862 | |
Arnaldo Carvalho de Melo | 58a5a7b | 2006-11-16 14:06:06 -0200 | [diff] [blame] | 863 | return sk_receive_skb(sk, skb, 1); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 864 | |
| 865 | no_dccp_socket: |
| 866 | if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) |
| 867 | goto discard_it; |
| 868 | /* |
| 869 | * Step 2: |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 870 | * If no socket ... |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 871 | * Generate Reset(No Connection) unless P.type == Reset |
| 872 | * Drop packet and return |
| 873 | */ |
| 874 | if (dh->dccph_type != DCCP_PKT_RESET) { |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 875 | DCCP_SKB_CB(skb)->dccpd_reset_code = |
| 876 | DCCP_RESET_CODE_NO_CONNECTION; |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 877 | dccp_v4_ctl_send_reset(sk, skb); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 878 | } |
| 879 | |
| 880 | discard_it: |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 881 | kfree_skb(skb); |
| 882 | return 0; |
| 883 | |
| 884 | discard_and_relse: |
| 885 | sock_put(sk); |
| 886 | goto discard_it; |
| 887 | } |
| 888 | |
Stephen Hemminger | 3b401a8 | 2009-09-01 19:25:04 +0000 | [diff] [blame] | 889 | 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] | 890 | .queue_xmit = ip_queue_xmit, |
| 891 | .send_check = dccp_v4_send_check, |
| 892 | .rebuild_header = inet_sk_rebuild_header, |
| 893 | .conn_request = dccp_v4_conn_request, |
| 894 | .syn_recv_sock = dccp_v4_request_recv_sock, |
| 895 | .net_header_len = sizeof(struct iphdr), |
| 896 | .setsockopt = ip_setsockopt, |
| 897 | .getsockopt = ip_getsockopt, |
| 898 | .addr2sockaddr = inet_csk_addr2sockaddr, |
| 899 | .sockaddr_len = sizeof(struct sockaddr_in), |
Arnaldo Carvalho de Melo | ab1e0a1 | 2008-02-03 04:06:04 -0800 | [diff] [blame] | 900 | .bind_conflict = inet_csk_bind_conflict, |
Dmitry Mishin | 3fdadf7 | 2006-03-20 22:45:21 -0800 | [diff] [blame] | 901 | #ifdef CONFIG_COMPAT |
Arnaldo Carvalho de Melo | 543d9cf | 2006-03-20 22:48:35 -0800 | [diff] [blame] | 902 | .compat_setsockopt = compat_ip_setsockopt, |
| 903 | .compat_getsockopt = compat_ip_getsockopt, |
Dmitry Mishin | 3fdadf7 | 2006-03-20 22:45:21 -0800 | [diff] [blame] | 904 | #endif |
Arnaldo Carvalho de Melo | 57cca05 | 2005-12-13 23:16:16 -0800 | [diff] [blame] | 905 | }; |
| 906 | |
Arnaldo Carvalho de Melo | 3e0fadc | 2006-03-20 21:23:15 -0800 | [diff] [blame] | 907 | static int dccp_v4_init_sock(struct sock *sk) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 908 | { |
Arnaldo Carvalho de Melo | 7247887 | 2006-03-20 22:00:37 -0800 | [diff] [blame] | 909 | static __u8 dccp_v4_ctl_sock_initialized; |
| 910 | 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] | 911 | |
Arnaldo Carvalho de Melo | 7247887 | 2006-03-20 22:00:37 -0800 | [diff] [blame] | 912 | if (err == 0) { |
| 913 | if (unlikely(!dccp_v4_ctl_sock_initialized)) |
| 914 | dccp_v4_ctl_sock_initialized = 1; |
Arnaldo Carvalho de Melo | 3e0fadc | 2006-03-20 21:23:15 -0800 | [diff] [blame] | 915 | inet_csk(sk)->icsk_af_ops = &dccp_ipv4_af_ops; |
Arnaldo Carvalho de Melo | 7247887 | 2006-03-20 22:00:37 -0800 | [diff] [blame] | 916 | } |
| 917 | |
Arnaldo Carvalho de Melo | 3e0fadc | 2006-03-20 21:23:15 -0800 | [diff] [blame] | 918 | return err; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 919 | } |
| 920 | |
Arnaldo Carvalho de Melo | 6d6ee43 | 2005-12-13 23:25:19 -0800 | [diff] [blame] | 921 | static struct timewait_sock_ops dccp_timewait_sock_ops = { |
| 922 | .twsk_obj_size = sizeof(struct inet_timewait_sock), |
| 923 | }; |
| 924 | |
Adrian Bunk | 5e0817f | 2006-03-20 21:58:29 -0800 | [diff] [blame] | 925 | static struct proto dccp_v4_prot = { |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 926 | .name = "DCCP", |
| 927 | .owner = THIS_MODULE, |
| 928 | .close = dccp_close, |
| 929 | .connect = dccp_v4_connect, |
| 930 | .disconnect = dccp_disconnect, |
| 931 | .ioctl = dccp_ioctl, |
| 932 | .init = dccp_v4_init_sock, |
| 933 | .setsockopt = dccp_setsockopt, |
| 934 | .getsockopt = dccp_getsockopt, |
| 935 | .sendmsg = dccp_sendmsg, |
| 936 | .recvmsg = dccp_recvmsg, |
| 937 | .backlog_rcv = dccp_v4_do_rcv, |
Arnaldo Carvalho de Melo | ab1e0a1 | 2008-02-03 04:06:04 -0800 | [diff] [blame] | 938 | .hash = inet_hash, |
| 939 | .unhash = inet_unhash, |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 940 | .accept = inet_csk_accept, |
Arnaldo Carvalho de Melo | ab1e0a1 | 2008-02-03 04:06:04 -0800 | [diff] [blame] | 941 | .get_port = inet_csk_get_port, |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 942 | .shutdown = dccp_shutdown, |
Arnaldo Carvalho de Melo | 3e0fadc | 2006-03-20 21:23:15 -0800 | [diff] [blame] | 943 | .destroy = dccp_destroy_sock, |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 944 | .orphan_count = &dccp_orphan_count, |
| 945 | .max_header = MAX_DCCP_HEADER, |
| 946 | .obj_size = sizeof(struct dccp_sock), |
Eric Dumazet | 3ab5aee | 2008-11-16 19:40:17 -0800 | [diff] [blame] | 947 | .slab_flags = SLAB_DESTROY_BY_RCU, |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 948 | .rsk_prot = &dccp_request_sock_ops, |
Arnaldo Carvalho de Melo | 6d6ee43 | 2005-12-13 23:25:19 -0800 | [diff] [blame] | 949 | .twsk_prot = &dccp_timewait_sock_ops, |
Pavel Emelyanov | 39d8cda | 2008-03-22 16:50:58 -0700 | [diff] [blame] | 950 | .h.hashinfo = &dccp_hashinfo, |
Arnaldo Carvalho de Melo | 543d9cf | 2006-03-20 22:48:35 -0800 | [diff] [blame] | 951 | #ifdef CONFIG_COMPAT |
| 952 | .compat_setsockopt = compat_dccp_setsockopt, |
| 953 | .compat_getsockopt = compat_dccp_getsockopt, |
| 954 | #endif |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 955 | }; |
Arnaldo Carvalho de Melo | 6d6ee43 | 2005-12-13 23:25:19 -0800 | [diff] [blame] | 956 | |
Alexey Dobriyan | 3261309 | 2009-09-14 12:21:47 +0000 | [diff] [blame] | 957 | static const struct net_protocol dccp_v4_protocol = { |
Arnaldo Carvalho de Melo | b61fafc | 2006-03-20 21:25:11 -0800 | [diff] [blame] | 958 | .handler = dccp_v4_rcv, |
| 959 | .err_handler = dccp_v4_err, |
| 960 | .no_policy = 1, |
Pavel Emelyanov | fc5f858 | 2008-04-13 22:31:05 -0700 | [diff] [blame] | 961 | .netns_ok = 1, |
Arnaldo Carvalho de Melo | b61fafc | 2006-03-20 21:25:11 -0800 | [diff] [blame] | 962 | }; |
| 963 | |
| 964 | static const struct proto_ops inet_dccp_ops = { |
Arnaldo Carvalho de Melo | 543d9cf | 2006-03-20 22:48:35 -0800 | [diff] [blame] | 965 | .family = PF_INET, |
| 966 | .owner = THIS_MODULE, |
| 967 | .release = inet_release, |
| 968 | .bind = inet_bind, |
| 969 | .connect = inet_stream_connect, |
| 970 | .socketpair = sock_no_socketpair, |
| 971 | .accept = inet_accept, |
| 972 | .getname = inet_getname, |
Arnaldo Carvalho de Melo | b61fafc | 2006-03-20 21:25:11 -0800 | [diff] [blame] | 973 | /* 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] | 974 | .poll = dccp_poll, |
| 975 | .ioctl = inet_ioctl, |
Arnaldo Carvalho de Melo | b61fafc | 2006-03-20 21:25:11 -0800 | [diff] [blame] | 976 | /* 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] | 977 | .listen = inet_dccp_listen, |
| 978 | .shutdown = inet_shutdown, |
| 979 | .setsockopt = sock_common_setsockopt, |
| 980 | .getsockopt = sock_common_getsockopt, |
| 981 | .sendmsg = inet_sendmsg, |
| 982 | .recvmsg = sock_common_recvmsg, |
| 983 | .mmap = sock_no_mmap, |
| 984 | .sendpage = sock_no_sendpage, |
Dmitry Mishin | 3fdadf7 | 2006-03-20 22:45:21 -0800 | [diff] [blame] | 985 | #ifdef CONFIG_COMPAT |
Arnaldo Carvalho de Melo | 543d9cf | 2006-03-20 22:48:35 -0800 | [diff] [blame] | 986 | .compat_setsockopt = compat_sock_common_setsockopt, |
| 987 | .compat_getsockopt = compat_sock_common_getsockopt, |
Dmitry Mishin | 3fdadf7 | 2006-03-20 22:45:21 -0800 | [diff] [blame] | 988 | #endif |
Arnaldo Carvalho de Melo | b61fafc | 2006-03-20 21:25:11 -0800 | [diff] [blame] | 989 | }; |
| 990 | |
| 991 | static struct inet_protosw dccp_v4_protosw = { |
| 992 | .type = SOCK_DCCP, |
| 993 | .protocol = IPPROTO_DCCP, |
| 994 | .prot = &dccp_v4_prot, |
| 995 | .ops = &inet_dccp_ops, |
Arnaldo Carvalho de Melo | b61fafc | 2006-03-20 21:25:11 -0800 | [diff] [blame] | 996 | .no_check = 0, |
| 997 | .flags = INET_PROTOSW_ICSK, |
| 998 | }; |
| 999 | |
Alexey Dobriyan | 2c8c1e7 | 2010-01-17 03:35:32 +0000 | [diff] [blame] | 1000 | static int __net_init dccp_v4_init_net(struct net *net) |
Pavel Emelyanov | 72a2d61 | 2008-04-13 22:29:13 -0700 | [diff] [blame] | 1001 | { |
Gerrit Renker | d14a0eb | 2010-03-14 20:13:19 +0000 | [diff] [blame] | 1002 | if (dccp_hashinfo.bhash == NULL) |
| 1003 | return -ESOCKTNOSUPPORT; |
Pavel Emelyanov | b76c4b2 | 2008-04-13 22:29:59 -0700 | [diff] [blame] | 1004 | |
Gerrit Renker | d14a0eb | 2010-03-14 20:13:19 +0000 | [diff] [blame] | 1005 | return inet_ctl_sock_create(&net->dccp.v4_ctl_sk, PF_INET, |
| 1006 | SOCK_DCCP, IPPROTO_DCCP, net); |
Pavel Emelyanov | 72a2d61 | 2008-04-13 22:29:13 -0700 | [diff] [blame] | 1007 | } |
| 1008 | |
Alexey Dobriyan | 2c8c1e7 | 2010-01-17 03:35:32 +0000 | [diff] [blame] | 1009 | static void __net_exit dccp_v4_exit_net(struct net *net) |
Pavel Emelyanov | 72a2d61 | 2008-04-13 22:29:13 -0700 | [diff] [blame] | 1010 | { |
Pavel Emelyanov | b76c4b2 | 2008-04-13 22:29:59 -0700 | [diff] [blame] | 1011 | inet_ctl_sock_destroy(net->dccp.v4_ctl_sk); |
Pavel Emelyanov | 72a2d61 | 2008-04-13 22:29:13 -0700 | [diff] [blame] | 1012 | } |
| 1013 | |
| 1014 | static struct pernet_operations dccp_v4_ops = { |
| 1015 | .init = dccp_v4_init_net, |
| 1016 | .exit = dccp_v4_exit_net, |
| 1017 | }; |
| 1018 | |
Arnaldo Carvalho de Melo | b61fafc | 2006-03-20 21:25:11 -0800 | [diff] [blame] | 1019 | static int __init dccp_v4_init(void) |
| 1020 | { |
| 1021 | int err = proto_register(&dccp_v4_prot, 1); |
| 1022 | |
| 1023 | if (err != 0) |
| 1024 | goto out; |
| 1025 | |
| 1026 | err = inet_add_protocol(&dccp_v4_protocol, IPPROTO_DCCP); |
| 1027 | if (err != 0) |
| 1028 | goto out_proto_unregister; |
| 1029 | |
| 1030 | inet_register_protosw(&dccp_v4_protosw); |
| 1031 | |
Pavel Emelyanov | 72a2d61 | 2008-04-13 22:29:13 -0700 | [diff] [blame] | 1032 | err = register_pernet_subsys(&dccp_v4_ops); |
| 1033 | if (err) |
| 1034 | goto out_destroy_ctl_sock; |
Arnaldo Carvalho de Melo | b61fafc | 2006-03-20 21:25:11 -0800 | [diff] [blame] | 1035 | out: |
| 1036 | return err; |
Pavel Emelyanov | 72a2d61 | 2008-04-13 22:29:13 -0700 | [diff] [blame] | 1037 | out_destroy_ctl_sock: |
Arnaldo Carvalho de Melo | b61fafc | 2006-03-20 21:25:11 -0800 | [diff] [blame] | 1038 | inet_unregister_protosw(&dccp_v4_protosw); |
| 1039 | inet_del_protocol(&dccp_v4_protocol, IPPROTO_DCCP); |
| 1040 | out_proto_unregister: |
| 1041 | proto_unregister(&dccp_v4_prot); |
| 1042 | goto out; |
| 1043 | } |
| 1044 | |
| 1045 | static void __exit dccp_v4_exit(void) |
| 1046 | { |
Pavel Emelyanov | 72a2d61 | 2008-04-13 22:29:13 -0700 | [diff] [blame] | 1047 | unregister_pernet_subsys(&dccp_v4_ops); |
Arnaldo Carvalho de Melo | b61fafc | 2006-03-20 21:25:11 -0800 | [diff] [blame] | 1048 | inet_unregister_protosw(&dccp_v4_protosw); |
| 1049 | inet_del_protocol(&dccp_v4_protocol, IPPROTO_DCCP); |
| 1050 | proto_unregister(&dccp_v4_prot); |
| 1051 | } |
| 1052 | |
| 1053 | module_init(dccp_v4_init); |
| 1054 | module_exit(dccp_v4_exit); |
| 1055 | |
| 1056 | /* |
| 1057 | * __stringify doesn't likes enums, so use SOCK_DCCP (6) and IPPROTO_DCCP (33) |
| 1058 | * values directly, Also cover the case where the protocol is not specified, |
| 1059 | * i.e. net-pf-PF_INET-proto-0-type-SOCK_DCCP |
| 1060 | */ |
Jean Delvare | 7131c6c | 2007-10-21 16:45:03 -0700 | [diff] [blame] | 1061 | MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET, 33, 6); |
| 1062 | MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET, 0, 6); |
Arnaldo Carvalho de Melo | b61fafc | 2006-03-20 21:25:11 -0800 | [diff] [blame] | 1063 | MODULE_LICENSE("GPL"); |
| 1064 | MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@mandriva.com>"); |
| 1065 | MODULE_DESCRIPTION("DCCP - Datagram Congestion Controlled Protocol"); |