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13#include <linux/dccp.h>
14#include <linux/gfp.h>
15#include <linux/kernel.h>
16#include <linux/skbuff.h>
17#include <linux/timer.h>
18
19#include <net/sock.h>
20#include <net/xfrm.h>
21#include <net/inet_timewait_sock.h>
22
23#include "ackvec.h"
24#include "ccid.h"
25#include "dccp.h"
26#include "feat.h"
27
28struct inet_timewait_death_row dccp_death_row = {
29 .sysctl_max_tw_buckets = NR_FILE * 2,
30 .hashinfo = &dccp_hashinfo,
31};
32
33EXPORT_SYMBOL_GPL(dccp_death_row);
34
35void dccp_time_wait(struct sock *sk, int state, int timeo)
36{
37 struct inet_timewait_sock *tw;
38
39 tw = inet_twsk_alloc(sk, &dccp_death_row, state);
40
41 if (tw != NULL) {
42 const struct inet_connection_sock *icsk = inet_csk(sk);
43 const int rto = (icsk->icsk_rto << 2) - (icsk->icsk_rto >> 1);
44#if IS_ENABLED(CONFIG_IPV6)
45 if (tw->tw_family == PF_INET6) {
46 tw->tw_v6_daddr = sk->sk_v6_daddr;
47 tw->tw_v6_rcv_saddr = sk->sk_v6_rcv_saddr;
48 tw->tw_ipv6only = sk->sk_ipv6only;
49 }
50#endif
51
52
53 if (timeo < rto)
54 timeo = rto;
55
56 tw->tw_timeout = DCCP_TIMEWAIT_LEN;
57 if (state == DCCP_TIME_WAIT)
58 timeo = DCCP_TIMEWAIT_LEN;
59
60
61
62
63
64 local_bh_disable();
65 inet_twsk_schedule(tw, timeo);
66
67
68
69 inet_twsk_hashdance(tw, sk, &dccp_hashinfo);
70 local_bh_enable();
71 } else {
72
73
74
75
76 DCCP_WARN("time wait bucket table overflow\n");
77 }
78
79 dccp_done(sk);
80}
81
82struct sock *dccp_create_openreq_child(const struct sock *sk,
83 const struct request_sock *req,
84 const struct sk_buff *skb)
85{
86
87
88
89
90
91
92 struct sock *newsk = inet_csk_clone_lock(sk, req, GFP_ATOMIC);
93
94 if (newsk != NULL) {
95 struct dccp_request_sock *dreq = dccp_rsk(req);
96 struct inet_connection_sock *newicsk = inet_csk(newsk);
97 struct dccp_sock *newdp = dccp_sk(newsk);
98
99 newdp->dccps_role = DCCP_ROLE_SERVER;
100 newdp->dccps_hc_rx_ackvec = NULL;
101 newdp->dccps_service_list = NULL;
102 newdp->dccps_service = dreq->dreq_service;
103 newdp->dccps_timestamp_echo = dreq->dreq_timestamp_echo;
104 newdp->dccps_timestamp_time = dreq->dreq_timestamp_time;
105 newicsk->icsk_rto = DCCP_TIMEOUT_INIT;
106
107 INIT_LIST_HEAD(&newdp->dccps_featneg);
108
109
110
111
112
113
114
115
116
117
118
119 newdp->dccps_iss = dreq->dreq_iss;
120 newdp->dccps_gss = dreq->dreq_gss;
121 newdp->dccps_gar = newdp->dccps_iss;
122 newdp->dccps_isr = dreq->dreq_isr;
123 newdp->dccps_gsr = dreq->dreq_gsr;
124
125
126
127
128 if (dccp_feat_activate_values(newsk, &dreq->dreq_featneg)) {
129 sk_free_unlock_clone(newsk);
130 return NULL;
131 }
132 dccp_init_xmit_timers(newsk);
133
134 __DCCP_INC_STATS(DCCP_MIB_PASSIVEOPENS);
135 }
136 return newsk;
137}
138
139EXPORT_SYMBOL_GPL(dccp_create_openreq_child);
140
141
142
143
144
145struct sock *dccp_check_req(struct sock *sk, struct sk_buff *skb,
146 struct request_sock *req)
147{
148 struct sock *child = NULL;
149 struct dccp_request_sock *dreq = dccp_rsk(req);
150 bool own_req;
151
152
153
154
155
156
157 spin_lock_bh(&dreq->dreq_lock);
158
159
160 if (dccp_hdr(skb)->dccph_type == DCCP_PKT_REQUEST) {
161
162 if (after48(DCCP_SKB_CB(skb)->dccpd_seq, dreq->dreq_gsr)) {
163 dccp_pr_debug("Retransmitted REQUEST\n");
164 dreq->dreq_gsr = DCCP_SKB_CB(skb)->dccpd_seq;
165
166
167
168
169
170 inet_rtx_syn_ack(sk, req);
171 }
172
173 goto out;
174 }
175
176 DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_PACKET_ERROR;
177
178 if (dccp_hdr(skb)->dccph_type != DCCP_PKT_ACK &&
179 dccp_hdr(skb)->dccph_type != DCCP_PKT_DATAACK)
180 goto drop;
181
182
183 if (!between48(DCCP_SKB_CB(skb)->dccpd_ack_seq,
184 dreq->dreq_iss, dreq->dreq_gss)) {
185 dccp_pr_debug("Invalid ACK number: ack_seq=%llu, "
186 "dreq_iss=%llu, dreq_gss=%llu\n",
187 (unsigned long long)
188 DCCP_SKB_CB(skb)->dccpd_ack_seq,
189 (unsigned long long) dreq->dreq_iss,
190 (unsigned long long) dreq->dreq_gss);
191 goto drop;
192 }
193
194 if (dccp_parse_options(sk, dreq, skb))
195 goto drop;
196
197 child = inet_csk(sk)->icsk_af_ops->syn_recv_sock(sk, skb, req, NULL,
198 req, &own_req);
199 if (child) {
200 child = inet_csk_complete_hashdance(sk, child, req, own_req);
201 goto out;
202 }
203
204 DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_TOO_BUSY;
205drop:
206 if (dccp_hdr(skb)->dccph_type != DCCP_PKT_RESET)
207 req->rsk_ops->send_reset(sk, skb);
208
209 inet_csk_reqsk_queue_drop(sk, req);
210out:
211 spin_unlock_bh(&dreq->dreq_lock);
212 return child;
213}
214
215EXPORT_SYMBOL_GPL(dccp_check_req);
216
217
218
219
220
221
222int dccp_child_process(struct sock *parent, struct sock *child,
223 struct sk_buff *skb)
224{
225 int ret = 0;
226 const int state = child->sk_state;
227
228 if (!sock_owned_by_user(child)) {
229 ret = dccp_rcv_state_process(child, skb, dccp_hdr(skb),
230 skb->len);
231
232
233 if (state == DCCP_RESPOND && child->sk_state != state)
234 parent->sk_data_ready(parent);
235 } else {
236
237
238
239
240 __sk_add_backlog(child, skb);
241 }
242
243 bh_unlock_sock(child);
244 sock_put(child);
245 return ret;
246}
247
248EXPORT_SYMBOL_GPL(dccp_child_process);
249
250void dccp_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb,
251 struct request_sock *rsk)
252{
253 DCCP_BUG("DCCP-ACK packets are never sent in LISTEN/RESPOND state");
254}
255
256EXPORT_SYMBOL_GPL(dccp_reqsk_send_ack);
257
258int dccp_reqsk_init(struct request_sock *req,
259 struct dccp_sock const *dp, struct sk_buff const *skb)
260{
261 struct dccp_request_sock *dreq = dccp_rsk(req);
262
263 spin_lock_init(&dreq->dreq_lock);
264 inet_rsk(req)->ir_rmt_port = dccp_hdr(skb)->dccph_sport;
265 inet_rsk(req)->ir_num = ntohs(dccp_hdr(skb)->dccph_dport);
266 inet_rsk(req)->acked = 0;
267 dreq->dreq_timestamp_echo = 0;
268
269
270 return dccp_feat_clone_list(&dp->dccps_featneg, &dreq->dreq_featneg);
271}
272
273EXPORT_SYMBOL_GPL(dccp_reqsk_init);
274