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13#include <linux/dccp.h>
14#include <linux/kernel.h>
15#include <linux/skbuff.h>
16#include <linux/timer.h>
17
18#include <net/sock.h>
19#include <net/xfrm.h>
20#include <net/inet_timewait_sock.h>
21
22#include "ackvec.h"
23#include "ccid.h"
24#include "dccp.h"
25#include "feat.h"
26
27struct inet_timewait_death_row dccp_death_row = {
28 .sysctl_max_tw_buckets = NR_FILE * 2,
29 .period = DCCP_TIMEWAIT_LEN / INET_TWDR_TWKILL_SLOTS,
30 .death_lock = __SPIN_LOCK_UNLOCKED(dccp_death_row.death_lock),
31 .hashinfo = &dccp_hashinfo,
32 .tw_timer = TIMER_INITIALIZER(inet_twdr_hangman, 0,
33 (unsigned long)&dccp_death_row),
34 .twkill_work = __WORK_INITIALIZER(dccp_death_row.twkill_work,
35 inet_twdr_twkill_work),
36
37
38 .twcal_hand = -1,
39 .twcal_timer = TIMER_INITIALIZER(inet_twdr_twcal_tick, 0,
40 (unsigned long)&dccp_death_row),
41};
42
43EXPORT_SYMBOL_GPL(dccp_death_row);
44
45void dccp_time_wait(struct sock *sk, int state, int timeo)
46{
47 struct inet_timewait_sock *tw = NULL;
48
49 if (dccp_death_row.tw_count < dccp_death_row.sysctl_max_tw_buckets)
50 tw = inet_twsk_alloc(sk, state);
51
52 if (tw != NULL) {
53 const struct inet_connection_sock *icsk = inet_csk(sk);
54 const int rto = (icsk->icsk_rto << 2) - (icsk->icsk_rto >> 1);
55#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
56 if (tw->tw_family == PF_INET6) {
57 const struct ipv6_pinfo *np = inet6_sk(sk);
58 struct inet6_timewait_sock *tw6;
59
60 tw->tw_ipv6_offset = inet6_tw_offset(sk->sk_prot);
61 tw6 = inet6_twsk((struct sock *)tw);
62 ipv6_addr_copy(&tw6->tw_v6_daddr, &np->daddr);
63 ipv6_addr_copy(&tw6->tw_v6_rcv_saddr, &np->rcv_saddr);
64 tw->tw_ipv6only = np->ipv6only;
65 }
66#endif
67
68 __inet_twsk_hashdance(tw, sk, &dccp_hashinfo);
69
70
71 if (timeo < rto)
72 timeo = rto;
73
74 tw->tw_timeout = DCCP_TIMEWAIT_LEN;
75 if (state == DCCP_TIME_WAIT)
76 timeo = DCCP_TIMEWAIT_LEN;
77
78 inet_twsk_schedule(tw, &dccp_death_row, timeo,
79 DCCP_TIMEWAIT_LEN);
80 inet_twsk_put(tw);
81 } else {
82
83
84
85
86 DCCP_WARN("time wait bucket table overflow\n");
87 }
88
89 dccp_done(sk);
90}
91
92struct sock *dccp_create_openreq_child(struct sock *sk,
93 const struct request_sock *req,
94 const struct sk_buff *skb)
95{
96
97
98
99
100
101
102 struct sock *newsk = inet_csk_clone(sk, req, GFP_ATOMIC);
103
104 if (newsk != NULL) {
105 struct dccp_request_sock *dreq = dccp_rsk(req);
106 struct inet_connection_sock *newicsk = inet_csk(newsk);
107 struct dccp_sock *newdp = dccp_sk(newsk);
108
109 newdp->dccps_role = DCCP_ROLE_SERVER;
110 newdp->dccps_hc_rx_ackvec = NULL;
111 newdp->dccps_service_list = NULL;
112 newdp->dccps_service = dreq->dreq_service;
113 newdp->dccps_timestamp_echo = dreq->dreq_timestamp_echo;
114 newdp->dccps_timestamp_time = dreq->dreq_timestamp_time;
115 newicsk->icsk_rto = DCCP_TIMEOUT_INIT;
116
117 INIT_LIST_HEAD(&newdp->dccps_featneg);
118
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122
123
124
125 newdp->dccps_gar = newdp->dccps_iss = dreq->dreq_iss;
126 dccp_update_gss(newsk, dreq->dreq_iss);
127
128 newdp->dccps_isr = dreq->dreq_isr;
129 dccp_update_gsr(newsk, dreq->dreq_isr);
130
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137
138
139 dccp_set_seqno(&newdp->dccps_swl,
140 max48(newdp->dccps_swl, newdp->dccps_isr));
141 dccp_set_seqno(&newdp->dccps_awl,
142 max48(newdp->dccps_awl, newdp->dccps_iss));
143
144
145
146
147
148 if (dccp_feat_activate_values(newsk, &dreq->dreq_featneg)) {
149
150
151 newsk->sk_destruct = NULL;
152 sk_free(newsk);
153 return NULL;
154 }
155 dccp_init_xmit_timers(newsk);
156
157 DCCP_INC_STATS_BH(DCCP_MIB_PASSIVEOPENS);
158 }
159 return newsk;
160}
161
162EXPORT_SYMBOL_GPL(dccp_create_openreq_child);
163
164
165
166
167
168struct sock *dccp_check_req(struct sock *sk, struct sk_buff *skb,
169 struct request_sock *req,
170 struct request_sock **prev)
171{
172 struct sock *child = NULL;
173 struct dccp_request_sock *dreq = dccp_rsk(req);
174
175
176 if (dccp_hdr(skb)->dccph_type == DCCP_PKT_REQUEST) {
177
178 if (after48(DCCP_SKB_CB(skb)->dccpd_seq, dreq->dreq_isr)) {
179 dccp_pr_debug("Retransmitted REQUEST\n");
180 dreq->dreq_isr = DCCP_SKB_CB(skb)->dccpd_seq;
181
182
183
184
185
186 req->retrans++;
187 req->rsk_ops->rtx_syn_ack(sk, req);
188 }
189
190 return NULL;
191 }
192
193 DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_PACKET_ERROR;
194
195 if (dccp_hdr(skb)->dccph_type != DCCP_PKT_ACK &&
196 dccp_hdr(skb)->dccph_type != DCCP_PKT_DATAACK)
197 goto drop;
198
199
200 if (DCCP_SKB_CB(skb)->dccpd_ack_seq != dreq->dreq_iss) {
201 dccp_pr_debug("Invalid ACK number: ack_seq=%llu, "
202 "dreq_iss=%llu\n",
203 (unsigned long long)
204 DCCP_SKB_CB(skb)->dccpd_ack_seq,
205 (unsigned long long) dreq->dreq_iss);
206 goto drop;
207 }
208
209 if (dccp_parse_options(sk, dreq, skb))
210 goto drop;
211
212 child = inet_csk(sk)->icsk_af_ops->syn_recv_sock(sk, skb, req, NULL);
213 if (child == NULL)
214 goto listen_overflow;
215
216 inet_csk_reqsk_queue_unlink(sk, req, prev);
217 inet_csk_reqsk_queue_removed(sk, req);
218 inet_csk_reqsk_queue_add(sk, req, child);
219out:
220 return child;
221listen_overflow:
222 dccp_pr_debug("listen_overflow!\n");
223 DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_TOO_BUSY;
224drop:
225 if (dccp_hdr(skb)->dccph_type != DCCP_PKT_RESET)
226 req->rsk_ops->send_reset(sk, skb);
227
228 inet_csk_reqsk_queue_drop(sk, req, prev);
229 goto out;
230}
231
232EXPORT_SYMBOL_GPL(dccp_check_req);
233
234
235
236
237
238
239int dccp_child_process(struct sock *parent, struct sock *child,
240 struct sk_buff *skb)
241{
242 int ret = 0;
243 const int state = child->sk_state;
244
245 if (!sock_owned_by_user(child)) {
246 ret = dccp_rcv_state_process(child, skb, dccp_hdr(skb),
247 skb->len);
248
249
250 if (state == DCCP_RESPOND && child->sk_state != state)
251 parent->sk_data_ready(parent, 0);
252 } else {
253
254
255
256
257 sk_add_backlog(child, skb);
258 }
259
260 bh_unlock_sock(child);
261 sock_put(child);
262 return ret;
263}
264
265EXPORT_SYMBOL_GPL(dccp_child_process);
266
267void dccp_reqsk_send_ack(struct sock *sk, struct sk_buff *skb,
268 struct request_sock *rsk)
269{
270 DCCP_BUG("DCCP-ACK packets are never sent in LISTEN/RESPOND state");
271}
272
273EXPORT_SYMBOL_GPL(dccp_reqsk_send_ack);
274
275int dccp_reqsk_init(struct request_sock *req,
276 struct dccp_sock const *dp, struct sk_buff const *skb)
277{
278 struct dccp_request_sock *dreq = dccp_rsk(req);
279
280 inet_rsk(req)->rmt_port = dccp_hdr(skb)->dccph_sport;
281 inet_rsk(req)->loc_port = dccp_hdr(skb)->dccph_dport;
282 inet_rsk(req)->acked = 0;
283 dreq->dreq_timestamp_echo = 0;
284
285
286 return dccp_feat_clone_list(&dp->dccps_featneg, &dreq->dreq_featneg);
287}
288
289EXPORT_SYMBOL_GPL(dccp_reqsk_init);
290