]>
Commit | Line | Data |
---|---|---|
7c657876 ACM |
1 | /* |
2 | * net/dccp/minisocks.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 | ||
7c657876 | 13 | #include <linux/dccp.h> |
8a73cd09 | 14 | #include <linux/kernel.h> |
7c657876 ACM |
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 | ||
ae31c339 | 22 | #include "ackvec.h" |
7c657876 ACM |
23 | #include "ccid.h" |
24 | #include "dccp.h" | |
afe00251 | 25 | #include "feat.h" |
7c657876 | 26 | |
64cf1e5d ACM |
27 | struct inet_timewait_death_row dccp_death_row = { |
28 | .sysctl_max_tw_buckets = NR_FILE * 2, | |
29 | .period = DCCP_TIMEWAIT_LEN / INET_TWDR_TWKILL_SLOTS, | |
4ef8d0ae | 30 | .death_lock = __SPIN_LOCK_UNLOCKED(dccp_death_row.death_lock), |
64cf1e5d ACM |
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, | |
c4028958 | 35 | inet_twdr_twkill_work), |
64cf1e5d ACM |
36 | /* Short-time timewait calendar */ |
37 | ||
38 | .twcal_hand = -1, | |
39 | .twcal_timer = TIMER_INITIALIZER(inet_twdr_twcal_tick, 0, | |
40 | (unsigned long)&dccp_death_row), | |
41 | }; | |
42 | ||
f21e68ca ACM |
43 | EXPORT_SYMBOL_GPL(dccp_death_row); |
44 | ||
7c657876 ACM |
45 | void dccp_time_wait(struct sock *sk, int state, int timeo) |
46 | { | |
64cf1e5d | 47 | struct inet_timewait_sock *tw = NULL; |
7c657876 | 48 | |
64cf1e5d ACM |
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); | |
3df80d93 ACM |
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; | |
64cf1e5d | 59 | |
3df80d93 ACM |
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 | |
64cf1e5d ACM |
67 | /* Linkage updates. */ |
68 | __inet_twsk_hashdance(tw, sk, &dccp_hashinfo); | |
69 | ||
70 | /* Get the TIME_WAIT timeout firing. */ | |
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 | /* Sorry, if we're out of memory, just CLOSE this | |
83 | * socket up. We've got bigger problems than | |
84 | * non-graceful socket closings. | |
85 | */ | |
59348b19 | 86 | DCCP_WARN("time wait bucket table overflow\n"); |
64cf1e5d ACM |
87 | } |
88 | ||
89 | dccp_done(sk); | |
7c657876 ACM |
90 | } |
91 | ||
92 | struct sock *dccp_create_openreq_child(struct sock *sk, | |
93 | const struct request_sock *req, | |
94 | const struct sk_buff *skb) | |
95 | { | |
96 | /* | |
97 | * Step 3: Process LISTEN state | |
98 | * | |
d83ca5ac GR |
99 | * (* Generate a new socket and switch to that socket *) |
100 | * Set S := new socket for this port pair | |
7c657876 ACM |
101 | */ |
102 | struct sock *newsk = inet_csk_clone(sk, req, GFP_ATOMIC); | |
103 | ||
104 | if (newsk != NULL) { | |
192b27ff | 105 | struct dccp_request_sock *dreq = dccp_rsk(req); |
99c72ce0 | 106 | struct inet_connection_sock *newicsk = inet_csk(newsk); |
7c657876 ACM |
107 | struct dccp_sock *newdp = dccp_sk(newsk); |
108 | ||
b4d4f7c7 GR |
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; | |
7c657876 | 116 | |
ac75773c | 117 | INIT_LIST_HEAD(&newdp->dccps_featneg); |
7c657876 ACM |
118 | /* |
119 | * Step 3: Process LISTEN state | |
120 | * | |
d83ca5ac GR |
121 | * Choose S.ISS (initial seqno) or set from Init Cookies |
122 | * Initialize S.GAR := S.ISS | |
123 | * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookies | |
7c657876 | 124 | */ |
be4c798a | 125 | newdp->dccps_gar = newdp->dccps_iss = dreq->dreq_iss; |
7c657876 ACM |
126 | dccp_update_gss(newsk, dreq->dreq_iss); |
127 | ||
be4c798a GR |
128 | newdp->dccps_isr = dreq->dreq_isr; |
129 | dccp_update_gsr(newsk, dreq->dreq_isr); | |
130 | ||
03ace394 ACM |
131 | /* |
132 | * SWL and AWL are initially adjusted so that they are not less than | |
133 | * the initial Sequence Numbers received and sent, respectively: | |
134 | * SWL := max(GSR + 1 - floor(W/4), ISR), | |
135 | * AWL := max(GSS - W' + 1, ISS). | |
136 | * These adjustments MUST be applied only at the beginning of the | |
137 | * connection. | |
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 | ||
192b27ff GR |
144 | /* |
145 | * Activate features after initialising the sequence numbers, | |
146 | * since CCID initialisation may depend on GSS, ISR, ISS etc. | |
147 | */ | |
148 | if (dccp_feat_activate_values(newsk, &dreq->dreq_featneg)) { | |
149 | /* It is still raw copy of parent, so invalidate | |
150 | * destructor and make plain sk_free() */ | |
151 | newsk->sk_destruct = NULL; | |
152 | sk_free(newsk); | |
153 | return NULL; | |
154 | } | |
7c657876 ACM |
155 | dccp_init_xmit_timers(newsk); |
156 | ||
157 | DCCP_INC_STATS_BH(DCCP_MIB_PASSIVEOPENS); | |
158 | } | |
159 | return newsk; | |
160 | } | |
161 | ||
f21e68ca ACM |
162 | EXPORT_SYMBOL_GPL(dccp_create_openreq_child); |
163 | ||
8109b02b | 164 | /* |
7c657876 ACM |
165 | * Process an incoming packet for RESPOND sockets represented |
166 | * as an request_sock. | |
167 | */ | |
168 | struct 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; | |
8109616e | 173 | struct dccp_request_sock *dreq = dccp_rsk(req); |
7c657876 ACM |
174 | |
175 | /* Check for retransmitted REQUEST */ | |
176 | if (dccp_hdr(skb)->dccph_type == DCCP_PKT_REQUEST) { | |
7c657876 | 177 | |
e11d9d30 | 178 | if (after48(DCCP_SKB_CB(skb)->dccpd_seq, dreq->dreq_isr)) { |
7c657876 | 179 | dccp_pr_debug("Retransmitted REQUEST\n"); |
e11d9d30 GR |
180 | dreq->dreq_isr = DCCP_SKB_CB(skb)->dccpd_seq; |
181 | /* | |
182 | * Send another RESPONSE packet | |
183 | * To protect against Request floods, increment retrans | |
184 | * counter (backoff, monitored by dccp_response_timer). | |
185 | */ | |
186 | req->retrans++; | |
e6b4d113 | 187 | req->rsk_ops->rtx_syn_ack(sk, req, NULL); |
7c657876 ACM |
188 | } |
189 | /* Network Duplicate, discard packet */ | |
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 | /* Invalid ACK */ | |
8109616e | 200 | if (DCCP_SKB_CB(skb)->dccpd_ack_seq != dreq->dreq_iss) { |
7690af3f ACM |
201 | dccp_pr_debug("Invalid ACK number: ack_seq=%llu, " |
202 | "dreq_iss=%llu\n", | |
f6ccf554 DM |
203 | (unsigned long long) |
204 | DCCP_SKB_CB(skb)->dccpd_ack_seq, | |
8109616e | 205 | (unsigned long long) dreq->dreq_iss); |
7c657876 ACM |
206 | goto drop; |
207 | } | |
208 | ||
8109616e GR |
209 | if (dccp_parse_options(sk, dreq, skb)) |
210 | goto drop; | |
211 | ||
57cca05a | 212 | child = inet_csk(sk)->icsk_af_ops->syn_recv_sock(sk, skb, req, NULL); |
7c657876 ACM |
213 | if (child == NULL) |
214 | goto listen_overflow; | |
215 | ||
7c657876 ACM |
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); | |
219 | out: | |
220 | return child; | |
221 | listen_overflow: | |
222 | dccp_pr_debug("listen_overflow!\n"); | |
223 | DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_TOO_BUSY; | |
224 | drop: | |
225 | if (dccp_hdr(skb)->dccph_type != DCCP_PKT_RESET) | |
cfb6eeb4 | 226 | req->rsk_ops->send_reset(sk, skb); |
7c657876 ACM |
227 | |
228 | inet_csk_reqsk_queue_drop(sk, req, prev); | |
229 | goto out; | |
230 | } | |
231 | ||
f21e68ca ACM |
232 | EXPORT_SYMBOL_GPL(dccp_check_req); |
233 | ||
7c657876 ACM |
234 | /* |
235 | * Queue segment on the new socket if the new socket is active, | |
236 | * otherwise we just shortcircuit this and continue with | |
237 | * the new socket. | |
238 | */ | |
239 | int 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)) { | |
7690af3f ACM |
246 | ret = dccp_rcv_state_process(child, skb, dccp_hdr(skb), |
247 | skb->len); | |
7c657876 ACM |
248 | |
249 | /* Wakeup parent, send SIGIO */ | |
250 | if (state == DCCP_RESPOND && child->sk_state != state) | |
251 | parent->sk_data_ready(parent, 0); | |
252 | } else { | |
253 | /* Alas, it is possible again, because we do lookup | |
254 | * in main socket hash table and lock on listening | |
255 | * socket does not protect us more. | |
256 | */ | |
257 | sk_add_backlog(child, skb); | |
258 | } | |
259 | ||
260 | bh_unlock_sock(child); | |
261 | sock_put(child); | |
262 | return ret; | |
263 | } | |
f21e68ca ACM |
264 | |
265 | EXPORT_SYMBOL_GPL(dccp_child_process); | |
8a73cd09 | 266 | |
6edafaaf GJ |
267 | void dccp_reqsk_send_ack(struct sock *sk, struct sk_buff *skb, |
268 | struct request_sock *rsk) | |
8a73cd09 | 269 | { |
59348b19 | 270 | DCCP_BUG("DCCP-ACK packets are never sent in LISTEN/RESPOND state"); |
8a73cd09 GR |
271 | } |
272 | ||
273 | EXPORT_SYMBOL_GPL(dccp_reqsk_send_ack); | |
cf557926 | 274 | |
ac75773c GR |
275 | int dccp_reqsk_init(struct request_sock *req, |
276 | struct dccp_sock const *dp, struct sk_buff const *skb) | |
cf557926 | 277 | { |
b4d4f7c7 GR |
278 | struct dccp_request_sock *dreq = dccp_rsk(req); |
279 | ||
280 | inet_rsk(req)->rmt_port = dccp_hdr(skb)->dccph_sport; | |
944f7502 | 281 | inet_rsk(req)->loc_port = dccp_hdr(skb)->dccph_dport; |
b4d4f7c7 | 282 | inet_rsk(req)->acked = 0; |
b4d4f7c7 | 283 | dreq->dreq_timestamp_echo = 0; |
ac75773c GR |
284 | |
285 | /* inherit feature negotiation options from listening socket */ | |
286 | return dccp_feat_clone_list(&dp->dccps_featneg, &dreq->dreq_featneg); | |
cf557926 GR |
287 | } |
288 | ||
289 | EXPORT_SYMBOL_GPL(dccp_reqsk_init); |