Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 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 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 13 | #include <linux/dccp.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 14 | #include <linux/gfp.h> |
Gerrit Renker | 8a73cd0 | 2006-11-10 12:32:01 -0200 | [diff] [blame] | 15 | #include <linux/kernel.h> |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 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 | |
Arnaldo Carvalho de Melo | ae31c33 | 2005-09-18 00:17:51 -0700 | [diff] [blame] | 23 | #include "ackvec.h" |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 24 | #include "ccid.h" |
| 25 | #include "dccp.h" |
Andrea Bittau | afe0025 | 2006-03-20 17:43:56 -0800 | [diff] [blame] | 26 | #include "feat.h" |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 27 | |
Arnaldo Carvalho de Melo | 64cf1e5 | 2005-08-09 20:45:21 -0700 | [diff] [blame] | 28 | struct inet_timewait_death_row dccp_death_row = { |
| 29 | .sysctl_max_tw_buckets = NR_FILE * 2, |
| 30 | .period = DCCP_TIMEWAIT_LEN / INET_TWDR_TWKILL_SLOTS, |
Milind Arun Choudhary | 4ef8d0a | 2007-04-26 01:37:44 -0700 | [diff] [blame] | 31 | .death_lock = __SPIN_LOCK_UNLOCKED(dccp_death_row.death_lock), |
Arnaldo Carvalho de Melo | 64cf1e5 | 2005-08-09 20:45:21 -0700 | [diff] [blame] | 32 | .hashinfo = &dccp_hashinfo, |
| 33 | .tw_timer = TIMER_INITIALIZER(inet_twdr_hangman, 0, |
| 34 | (unsigned long)&dccp_death_row), |
| 35 | .twkill_work = __WORK_INITIALIZER(dccp_death_row.twkill_work, |
David Howells | c402895 | 2006-11-22 14:57:56 +0000 | [diff] [blame] | 36 | inet_twdr_twkill_work), |
Arnaldo Carvalho de Melo | 64cf1e5 | 2005-08-09 20:45:21 -0700 | [diff] [blame] | 37 | /* Short-time timewait calendar */ |
| 38 | |
| 39 | .twcal_hand = -1, |
| 40 | .twcal_timer = TIMER_INITIALIZER(inet_twdr_twcal_tick, 0, |
| 41 | (unsigned long)&dccp_death_row), |
| 42 | }; |
| 43 | |
Arnaldo Carvalho de Melo | f21e68c | 2005-12-13 23:24:16 -0800 | [diff] [blame] | 44 | EXPORT_SYMBOL_GPL(dccp_death_row); |
| 45 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 46 | void dccp_time_wait(struct sock *sk, int state, int timeo) |
| 47 | { |
Arnaldo Carvalho de Melo | 64cf1e5 | 2005-08-09 20:45:21 -0700 | [diff] [blame] | 48 | struct inet_timewait_sock *tw = NULL; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 49 | |
Arnaldo Carvalho de Melo | 64cf1e5 | 2005-08-09 20:45:21 -0700 | [diff] [blame] | 50 | if (dccp_death_row.tw_count < dccp_death_row.sysctl_max_tw_buckets) |
| 51 | tw = inet_twsk_alloc(sk, state); |
| 52 | |
| 53 | if (tw != NULL) { |
| 54 | const struct inet_connection_sock *icsk = inet_csk(sk); |
| 55 | const int rto = (icsk->icsk_rto << 2) - (icsk->icsk_rto >> 1); |
Arnaldo Carvalho de Melo | 3df80d9 | 2005-12-13 23:24:53 -0800 | [diff] [blame] | 56 | #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) |
| 57 | if (tw->tw_family == PF_INET6) { |
| 58 | const struct ipv6_pinfo *np = inet6_sk(sk); |
| 59 | struct inet6_timewait_sock *tw6; |
Arnaldo Carvalho de Melo | 64cf1e5 | 2005-08-09 20:45:21 -0700 | [diff] [blame] | 60 | |
Arnaldo Carvalho de Melo | 3df80d9 | 2005-12-13 23:24:53 -0800 | [diff] [blame] | 61 | tw->tw_ipv6_offset = inet6_tw_offset(sk->sk_prot); |
| 62 | tw6 = inet6_twsk((struct sock *)tw); |
| 63 | ipv6_addr_copy(&tw6->tw_v6_daddr, &np->daddr); |
| 64 | ipv6_addr_copy(&tw6->tw_v6_rcv_saddr, &np->rcv_saddr); |
| 65 | tw->tw_ipv6only = np->ipv6only; |
| 66 | } |
| 67 | #endif |
Arnaldo Carvalho de Melo | 64cf1e5 | 2005-08-09 20:45:21 -0700 | [diff] [blame] | 68 | /* Linkage updates. */ |
| 69 | __inet_twsk_hashdance(tw, sk, &dccp_hashinfo); |
| 70 | |
| 71 | /* Get the TIME_WAIT timeout firing. */ |
| 72 | if (timeo < rto) |
| 73 | timeo = rto; |
| 74 | |
| 75 | tw->tw_timeout = DCCP_TIMEWAIT_LEN; |
| 76 | if (state == DCCP_TIME_WAIT) |
| 77 | timeo = DCCP_TIMEWAIT_LEN; |
| 78 | |
| 79 | inet_twsk_schedule(tw, &dccp_death_row, timeo, |
| 80 | DCCP_TIMEWAIT_LEN); |
| 81 | inet_twsk_put(tw); |
| 82 | } else { |
| 83 | /* Sorry, if we're out of memory, just CLOSE this |
| 84 | * socket up. We've got bigger problems than |
| 85 | * non-graceful socket closings. |
| 86 | */ |
Gerrit Renker | 59348b1 | 2006-11-20 18:39:23 -0200 | [diff] [blame] | 87 | DCCP_WARN("time wait bucket table overflow\n"); |
Arnaldo Carvalho de Melo | 64cf1e5 | 2005-08-09 20:45:21 -0700 | [diff] [blame] | 88 | } |
| 89 | |
| 90 | dccp_done(sk); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 91 | } |
| 92 | |
| 93 | struct sock *dccp_create_openreq_child(struct sock *sk, |
| 94 | const struct request_sock *req, |
| 95 | const struct sk_buff *skb) |
| 96 | { |
| 97 | /* |
| 98 | * Step 3: Process LISTEN state |
| 99 | * |
Gerrit Renker | d83ca5a | 2006-11-10 16:29:14 -0200 | [diff] [blame] | 100 | * (* Generate a new socket and switch to that socket *) |
| 101 | * Set S := new socket for this port pair |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 102 | */ |
| 103 | struct sock *newsk = inet_csk_clone(sk, req, GFP_ATOMIC); |
| 104 | |
| 105 | if (newsk != NULL) { |
Gerrit Renker | 192b27f | 2008-12-08 01:15:55 -0800 | [diff] [blame] | 106 | struct dccp_request_sock *dreq = dccp_rsk(req); |
Gerrit Renker | 99c72ce | 2007-03-06 14:24:44 -0800 | [diff] [blame] | 107 | struct inet_connection_sock *newicsk = inet_csk(newsk); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 108 | struct dccp_sock *newdp = dccp_sk(newsk); |
| 109 | |
Gerrit Renker | b4d4f7c | 2007-12-13 12:37:19 -0200 | [diff] [blame] | 110 | newdp->dccps_role = DCCP_ROLE_SERVER; |
| 111 | newdp->dccps_hc_rx_ackvec = NULL; |
| 112 | newdp->dccps_service_list = NULL; |
| 113 | newdp->dccps_service = dreq->dreq_service; |
| 114 | newdp->dccps_timestamp_echo = dreq->dreq_timestamp_echo; |
| 115 | newdp->dccps_timestamp_time = dreq->dreq_timestamp_time; |
| 116 | newicsk->icsk_rto = DCCP_TIMEOUT_INIT; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 117 | |
Gerrit Renker | ac75773 | 2008-11-04 23:55:49 -0800 | [diff] [blame] | 118 | INIT_LIST_HEAD(&newdp->dccps_featneg); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 119 | /* |
| 120 | * Step 3: Process LISTEN state |
| 121 | * |
Gerrit Renker | d83ca5a | 2006-11-10 16:29:14 -0200 | [diff] [blame] | 122 | * Choose S.ISS (initial seqno) or set from Init Cookies |
| 123 | * Initialize S.GAR := S.ISS |
Gerrit Renker | 0b53d46 | 2010-10-11 20:35:40 +0200 | [diff] [blame] | 124 | * Set S.ISR, S.GSR from packet (or Init Cookies) |
| 125 | * |
| 126 | * Setting AWL/AWH and SWL/SWH happens as part of the feature |
| 127 | * activation below, as these windows all depend on the local |
| 128 | * and remote Sequence Window feature values (7.5.2). |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 129 | */ |
Gerrit Renker | 0b53d46 | 2010-10-11 20:35:40 +0200 | [diff] [blame] | 130 | newdp->dccps_gss = newdp->dccps_iss = dreq->dreq_iss; |
| 131 | newdp->dccps_gar = newdp->dccps_iss; |
| 132 | newdp->dccps_gsr = newdp->dccps_isr = dreq->dreq_isr; |
Gerrit Renker | be4c798 | 2008-06-11 11:19:10 +0100 | [diff] [blame] | 133 | |
Arnaldo Carvalho de Melo | 03ace39 | 2005-08-21 05:36:45 -0300 | [diff] [blame] | 134 | /* |
Gerrit Renker | 0b53d46 | 2010-10-11 20:35:40 +0200 | [diff] [blame] | 135 | * Activate features: initialise CCIDs, sequence windows etc. |
Gerrit Renker | 192b27f | 2008-12-08 01:15:55 -0800 | [diff] [blame] | 136 | */ |
| 137 | if (dccp_feat_activate_values(newsk, &dreq->dreq_featneg)) { |
| 138 | /* It is still raw copy of parent, so invalidate |
| 139 | * destructor and make plain sk_free() */ |
| 140 | newsk->sk_destruct = NULL; |
| 141 | sk_free(newsk); |
| 142 | return NULL; |
| 143 | } |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 144 | dccp_init_xmit_timers(newsk); |
| 145 | |
| 146 | DCCP_INC_STATS_BH(DCCP_MIB_PASSIVEOPENS); |
| 147 | } |
| 148 | return newsk; |
| 149 | } |
| 150 | |
Arnaldo Carvalho de Melo | f21e68c | 2005-12-13 23:24:16 -0800 | [diff] [blame] | 151 | EXPORT_SYMBOL_GPL(dccp_create_openreq_child); |
| 152 | |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 153 | /* |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 154 | * Process an incoming packet for RESPOND sockets represented |
| 155 | * as an request_sock. |
| 156 | */ |
| 157 | struct sock *dccp_check_req(struct sock *sk, struct sk_buff *skb, |
| 158 | struct request_sock *req, |
| 159 | struct request_sock **prev) |
| 160 | { |
| 161 | struct sock *child = NULL; |
Gerrit Renker | 8109616 | 2007-12-13 12:31:26 -0200 | [diff] [blame] | 162 | struct dccp_request_sock *dreq = dccp_rsk(req); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 163 | |
| 164 | /* Check for retransmitted REQUEST */ |
| 165 | if (dccp_hdr(skb)->dccph_type == DCCP_PKT_REQUEST) { |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 166 | |
Gerrit Renker | e11d9d3 | 2006-11-13 13:12:07 -0200 | [diff] [blame] | 167 | if (after48(DCCP_SKB_CB(skb)->dccpd_seq, dreq->dreq_isr)) { |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 168 | dccp_pr_debug("Retransmitted REQUEST\n"); |
Gerrit Renker | e11d9d3 | 2006-11-13 13:12:07 -0200 | [diff] [blame] | 169 | dreq->dreq_isr = DCCP_SKB_CB(skb)->dccpd_seq; |
| 170 | /* |
| 171 | * Send another RESPONSE packet |
| 172 | * To protect against Request floods, increment retrans |
| 173 | * counter (backoff, monitored by dccp_response_timer). |
| 174 | */ |
| 175 | req->retrans++; |
William Allen Simpson | e6b4d11 | 2009-12-02 18:07:39 +0000 | [diff] [blame] | 176 | req->rsk_ops->rtx_syn_ack(sk, req, NULL); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 177 | } |
| 178 | /* Network Duplicate, discard packet */ |
| 179 | return NULL; |
| 180 | } |
| 181 | |
| 182 | DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_PACKET_ERROR; |
| 183 | |
| 184 | if (dccp_hdr(skb)->dccph_type != DCCP_PKT_ACK && |
| 185 | dccp_hdr(skb)->dccph_type != DCCP_PKT_DATAACK) |
| 186 | goto drop; |
| 187 | |
| 188 | /* Invalid ACK */ |
Gerrit Renker | 8109616 | 2007-12-13 12:31:26 -0200 | [diff] [blame] | 189 | if (DCCP_SKB_CB(skb)->dccpd_ack_seq != dreq->dreq_iss) { |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 190 | dccp_pr_debug("Invalid ACK number: ack_seq=%llu, " |
| 191 | "dreq_iss=%llu\n", |
David S. Miller | f6ccf554 | 2005-08-09 20:27:14 -0700 | [diff] [blame] | 192 | (unsigned long long) |
| 193 | DCCP_SKB_CB(skb)->dccpd_ack_seq, |
Gerrit Renker | 8109616 | 2007-12-13 12:31:26 -0200 | [diff] [blame] | 194 | (unsigned long long) dreq->dreq_iss); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 195 | goto drop; |
| 196 | } |
| 197 | |
Gerrit Renker | 8109616 | 2007-12-13 12:31:26 -0200 | [diff] [blame] | 198 | if (dccp_parse_options(sk, dreq, skb)) |
| 199 | goto drop; |
| 200 | |
Arnaldo Carvalho de Melo | 57cca05 | 2005-12-13 23:16:16 -0800 | [diff] [blame] | 201 | child = inet_csk(sk)->icsk_af_ops->syn_recv_sock(sk, skb, req, NULL); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 202 | if (child == NULL) |
| 203 | goto listen_overflow; |
| 204 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 205 | inet_csk_reqsk_queue_unlink(sk, req, prev); |
| 206 | inet_csk_reqsk_queue_removed(sk, req); |
| 207 | inet_csk_reqsk_queue_add(sk, req, child); |
| 208 | out: |
| 209 | return child; |
| 210 | listen_overflow: |
| 211 | dccp_pr_debug("listen_overflow!\n"); |
| 212 | DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_TOO_BUSY; |
| 213 | drop: |
| 214 | if (dccp_hdr(skb)->dccph_type != DCCP_PKT_RESET) |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 215 | req->rsk_ops->send_reset(sk, skb); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 216 | |
| 217 | inet_csk_reqsk_queue_drop(sk, req, prev); |
| 218 | goto out; |
| 219 | } |
| 220 | |
Arnaldo Carvalho de Melo | f21e68c | 2005-12-13 23:24:16 -0800 | [diff] [blame] | 221 | EXPORT_SYMBOL_GPL(dccp_check_req); |
| 222 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 223 | /* |
| 224 | * Queue segment on the new socket if the new socket is active, |
| 225 | * otherwise we just shortcircuit this and continue with |
| 226 | * the new socket. |
| 227 | */ |
| 228 | int dccp_child_process(struct sock *parent, struct sock *child, |
| 229 | struct sk_buff *skb) |
| 230 | { |
| 231 | int ret = 0; |
| 232 | const int state = child->sk_state; |
| 233 | |
| 234 | if (!sock_owned_by_user(child)) { |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 235 | ret = dccp_rcv_state_process(child, skb, dccp_hdr(skb), |
| 236 | skb->len); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 237 | |
| 238 | /* Wakeup parent, send SIGIO */ |
| 239 | if (state == DCCP_RESPOND && child->sk_state != state) |
| 240 | parent->sk_data_ready(parent, 0); |
| 241 | } else { |
| 242 | /* Alas, it is possible again, because we do lookup |
| 243 | * in main socket hash table and lock on listening |
| 244 | * socket does not protect us more. |
| 245 | */ |
Zhu Yi | a3a858f | 2010-03-04 18:01:47 +0000 | [diff] [blame] | 246 | __sk_add_backlog(child, skb); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 247 | } |
| 248 | |
| 249 | bh_unlock_sock(child); |
| 250 | sock_put(child); |
| 251 | return ret; |
| 252 | } |
Arnaldo Carvalho de Melo | f21e68c | 2005-12-13 23:24:16 -0800 | [diff] [blame] | 253 | |
| 254 | EXPORT_SYMBOL_GPL(dccp_child_process); |
Gerrit Renker | 8a73cd0 | 2006-11-10 12:32:01 -0200 | [diff] [blame] | 255 | |
Gui Jianfeng | 6edafaa | 2008-08-06 23:50:04 -0700 | [diff] [blame] | 256 | void dccp_reqsk_send_ack(struct sock *sk, struct sk_buff *skb, |
| 257 | struct request_sock *rsk) |
Gerrit Renker | 8a73cd0 | 2006-11-10 12:32:01 -0200 | [diff] [blame] | 258 | { |
Gerrit Renker | 59348b1 | 2006-11-20 18:39:23 -0200 | [diff] [blame] | 259 | DCCP_BUG("DCCP-ACK packets are never sent in LISTEN/RESPOND state"); |
Gerrit Renker | 8a73cd0 | 2006-11-10 12:32:01 -0200 | [diff] [blame] | 260 | } |
| 261 | |
| 262 | EXPORT_SYMBOL_GPL(dccp_reqsk_send_ack); |
Gerrit Renker | cf55792 | 2006-11-10 16:08:37 -0200 | [diff] [blame] | 263 | |
Gerrit Renker | ac75773 | 2008-11-04 23:55:49 -0800 | [diff] [blame] | 264 | int dccp_reqsk_init(struct request_sock *req, |
| 265 | struct dccp_sock const *dp, struct sk_buff const *skb) |
Gerrit Renker | cf55792 | 2006-11-10 16:08:37 -0200 | [diff] [blame] | 266 | { |
Gerrit Renker | b4d4f7c | 2007-12-13 12:37:19 -0200 | [diff] [blame] | 267 | struct dccp_request_sock *dreq = dccp_rsk(req); |
| 268 | |
| 269 | inet_rsk(req)->rmt_port = dccp_hdr(skb)->dccph_sport; |
Gerrit Renker | 944f750 | 2008-10-19 23:36:47 -0700 | [diff] [blame] | 270 | inet_rsk(req)->loc_port = dccp_hdr(skb)->dccph_dport; |
Gerrit Renker | b4d4f7c | 2007-12-13 12:37:19 -0200 | [diff] [blame] | 271 | inet_rsk(req)->acked = 0; |
Gerrit Renker | b4d4f7c | 2007-12-13 12:37:19 -0200 | [diff] [blame] | 272 | dreq->dreq_timestamp_echo = 0; |
Gerrit Renker | ac75773 | 2008-11-04 23:55:49 -0800 | [diff] [blame] | 273 | |
| 274 | /* inherit feature negotiation options from listening socket */ |
| 275 | return dccp_feat_clone_list(&dp->dccps_featneg, &dreq->dreq_featneg); |
Gerrit Renker | cf55792 | 2006-11-10 16:08:37 -0200 | [diff] [blame] | 276 | } |
| 277 | |
| 278 | EXPORT_SYMBOL_GPL(dccp_reqsk_init); |