Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 1 | /* |
| 2 | * net/dccp/output.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 | |
| 13 | #include <linux/config.h> |
| 14 | #include <linux/dccp.h> |
| 15 | #include <linux/skbuff.h> |
| 16 | |
| 17 | #include <net/sock.h> |
| 18 | |
Arnaldo Carvalho de Melo | ae31c33 | 2005-09-18 00:17:51 -0700 | [diff] [blame] | 19 | #include "ackvec.h" |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 20 | #include "ccid.h" |
| 21 | #include "dccp.h" |
| 22 | |
| 23 | static inline void dccp_event_ack_sent(struct sock *sk) |
| 24 | { |
| 25 | inet_csk_clear_xmit_timer(sk, ICSK_TIME_DACK); |
| 26 | } |
| 27 | |
| 28 | /* |
| 29 | * All SKB's seen here are completely headerless. It is our |
| 30 | * job to build the DCCP header, and pass the packet down to |
| 31 | * IP so it can do the same plus pass the packet off to the |
| 32 | * device. |
| 33 | */ |
| 34 | int dccp_transmit_skb(struct sock *sk, struct sk_buff *skb) |
| 35 | { |
| 36 | if (likely(skb != NULL)) { |
| 37 | const struct inet_sock *inet = inet_sk(sk); |
| 38 | struct dccp_sock *dp = dccp_sk(sk); |
| 39 | struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb); |
| 40 | struct dccp_hdr *dh; |
| 41 | /* XXX For now we're using only 48 bits sequence numbers */ |
| 42 | const int dccp_header_size = sizeof(*dh) + |
| 43 | sizeof(struct dccp_hdr_ext) + |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 44 | dccp_packet_hdr_len(dcb->dccpd_type); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 45 | int err, set_ack = 1; |
| 46 | u64 ackno = dp->dccps_gsr; |
| 47 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 48 | dccp_inc_seqno(&dp->dccps_gss); |
| 49 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 50 | switch (dcb->dccpd_type) { |
| 51 | case DCCP_PKT_DATA: |
| 52 | set_ack = 0; |
| 53 | break; |
| 54 | case DCCP_PKT_SYNC: |
| 55 | case DCCP_PKT_SYNCACK: |
| 56 | ackno = dcb->dccpd_seq; |
| 57 | break; |
| 58 | } |
Arnaldo Carvalho de Melo | 2411772 | 2005-08-21 05:40:16 -0300 | [diff] [blame] | 59 | |
| 60 | dcb->dccpd_seq = dp->dccps_gss; |
| 61 | dccp_insert_options(sk, skb); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 62 | |
| 63 | skb->h.raw = skb_push(skb, dccp_header_size); |
| 64 | dh = dccp_hdr(skb); |
Herbert Xu | fda0fd6 | 2005-10-14 16:38:49 +1000 | [diff] [blame] | 65 | |
| 66 | if (!skb->sk) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 67 | skb_set_owner_w(skb, sk); |
| 68 | |
| 69 | /* Build DCCP header and checksum it. */ |
| 70 | memset(dh, 0, dccp_header_size); |
| 71 | dh->dccph_type = dcb->dccpd_type; |
| 72 | dh->dccph_sport = inet->sport; |
| 73 | dh->dccph_dport = inet->dport; |
| 74 | dh->dccph_doff = (dccp_header_size + dcb->dccpd_opt_len) / 4; |
| 75 | dh->dccph_ccval = dcb->dccpd_ccval; |
| 76 | /* XXX For now we're using only 48 bits sequence numbers */ |
| 77 | dh->dccph_x = 1; |
| 78 | |
| 79 | dp->dccps_awh = dp->dccps_gss; |
| 80 | dccp_hdr_set_seq(dh, dp->dccps_gss); |
| 81 | if (set_ack) |
| 82 | dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), ackno); |
| 83 | |
| 84 | switch (dcb->dccpd_type) { |
| 85 | case DCCP_PKT_REQUEST: |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 86 | dccp_hdr_request(skb)->dccph_req_service = |
Arnaldo Carvalho de Melo | 67e6b62 | 2005-09-16 16:58:40 -0700 | [diff] [blame] | 87 | dp->dccps_service; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 88 | break; |
| 89 | case DCCP_PKT_RESET: |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 90 | dccp_hdr_reset(skb)->dccph_reset_code = |
| 91 | dcb->dccpd_reset_code; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 92 | break; |
| 93 | } |
| 94 | |
Yoshifumi Nishida | 95b81ef | 2005-08-09 20:15:35 -0700 | [diff] [blame] | 95 | dh->dccph_checksum = dccp_v4_checksum(skb, inet->saddr, |
| 96 | inet->daddr); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 97 | |
Arnaldo Carvalho de Melo | 7ad07e7 | 2005-08-23 21:50:06 -0700 | [diff] [blame] | 98 | if (set_ack) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 99 | dccp_event_ack_sent(sk); |
| 100 | |
| 101 | DCCP_INC_STATS(DCCP_MIB_OUTSEGS); |
| 102 | |
Herbert Xu | 49c5bfa | 2005-10-18 12:03:28 +1000 | [diff] [blame] | 103 | memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 104 | err = ip_queue_xmit(skb, 0); |
| 105 | if (err <= 0) |
| 106 | return err; |
| 107 | |
| 108 | /* NET_XMIT_CN is special. It does not guarantee, |
| 109 | * that this packet is lost. It tells that device |
| 110 | * is about to start to drop packets or already |
| 111 | * drops some packets of the same priority and |
| 112 | * invokes us to send less aggressively. |
| 113 | */ |
| 114 | return err == NET_XMIT_CN ? 0 : err; |
| 115 | } |
| 116 | return -ENOBUFS; |
| 117 | } |
| 118 | |
| 119 | unsigned int dccp_sync_mss(struct sock *sk, u32 pmtu) |
| 120 | { |
| 121 | struct dccp_sock *dp = dccp_sk(sk); |
| 122 | int mss_now; |
| 123 | |
| 124 | /* |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 125 | * FIXME: we really should be using the af_specific thing to support |
| 126 | * IPv6. |
| 127 | * mss_now = pmtu - tp->af_specific->net_header_len - |
| 128 | * sizeof(struct dccp_hdr) - sizeof(struct dccp_hdr_ext); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 129 | */ |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 130 | mss_now = pmtu - sizeof(struct iphdr) - sizeof(struct dccp_hdr) - |
| 131 | sizeof(struct dccp_hdr_ext); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 132 | |
| 133 | /* Now subtract optional transport overhead */ |
| 134 | mss_now -= dp->dccps_ext_header_len; |
| 135 | |
| 136 | /* |
| 137 | * FIXME: this should come from the CCID infrastructure, where, say, |
| 138 | * TFRC will say it wants TIMESTAMPS, ELAPSED time, etc, for now lets |
| 139 | * put a rough estimate for NDP + TIMESTAMP + TIMESTAMP_ECHO + ELAPSED |
| 140 | * TIME + TFRC_OPT_LOSS_EVENT_RATE + TFRC_OPT_RECEIVE_RATE + padding to |
| 141 | * make it a multiple of 4 |
| 142 | */ |
| 143 | |
| 144 | mss_now -= ((5 + 6 + 10 + 6 + 6 + 6 + 3) / 4) * 4; |
| 145 | |
| 146 | /* And store cached results */ |
| 147 | dp->dccps_pmtu_cookie = pmtu; |
| 148 | dp->dccps_mss_cache = mss_now; |
| 149 | |
| 150 | return mss_now; |
| 151 | } |
| 152 | |
Arnaldo Carvalho de Melo | c530cfb | 2005-08-29 02:15:54 -0300 | [diff] [blame] | 153 | void dccp_write_space(struct sock *sk) |
| 154 | { |
| 155 | read_lock(&sk->sk_callback_lock); |
| 156 | |
| 157 | if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) |
| 158 | wake_up_interruptible(sk->sk_sleep); |
| 159 | /* Should agree with poll, otherwise some programs break */ |
| 160 | if (sock_writeable(sk)) |
| 161 | sk_wake_async(sk, 2, POLL_OUT); |
| 162 | |
| 163 | read_unlock(&sk->sk_callback_lock); |
| 164 | } |
| 165 | |
Arnaldo Carvalho de Melo | d6809c1 | 2005-08-27 03:06:35 -0300 | [diff] [blame] | 166 | /** |
| 167 | * dccp_wait_for_ccid - Wait for ccid to tell us we can send a packet |
| 168 | * @sk: socket to wait for |
| 169 | * @timeo: for how long |
| 170 | */ |
| 171 | static int dccp_wait_for_ccid(struct sock *sk, struct sk_buff *skb, |
| 172 | long *timeo) |
| 173 | { |
| 174 | struct dccp_sock *dp = dccp_sk(sk); |
| 175 | DEFINE_WAIT(wait); |
| 176 | long delay; |
| 177 | int rc; |
| 178 | |
| 179 | while (1) { |
| 180 | prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE); |
| 181 | |
| 182 | if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN)) |
| 183 | goto do_error; |
| 184 | if (!*timeo) |
| 185 | goto do_nonblock; |
| 186 | if (signal_pending(current)) |
| 187 | goto do_interrupted; |
| 188 | |
| 189 | rc = ccid_hc_tx_send_packet(dp->dccps_hc_tx_ccid, sk, skb, |
| 190 | skb->len); |
| 191 | if (rc <= 0) |
| 192 | break; |
| 193 | delay = msecs_to_jiffies(rc); |
| 194 | if (delay > *timeo || delay < 0) |
| 195 | goto do_nonblock; |
| 196 | |
| 197 | sk->sk_write_pending++; |
| 198 | release_sock(sk); |
| 199 | *timeo -= schedule_timeout(delay); |
| 200 | lock_sock(sk); |
| 201 | sk->sk_write_pending--; |
| 202 | } |
| 203 | out: |
| 204 | finish_wait(sk->sk_sleep, &wait); |
| 205 | return rc; |
| 206 | |
| 207 | do_error: |
| 208 | rc = -EPIPE; |
| 209 | goto out; |
| 210 | do_nonblock: |
| 211 | rc = -EAGAIN; |
| 212 | goto out; |
| 213 | do_interrupted: |
| 214 | rc = sock_intr_errno(*timeo); |
| 215 | goto out; |
| 216 | } |
| 217 | |
| 218 | int dccp_write_xmit(struct sock *sk, struct sk_buff *skb, long *timeo) |
Arnaldo Carvalho de Melo | 27258ee | 2005-08-09 20:30:56 -0700 | [diff] [blame] | 219 | { |
| 220 | const struct dccp_sock *dp = dccp_sk(sk); |
Arnaldo Carvalho de Melo | d6809c1 | 2005-08-27 03:06:35 -0300 | [diff] [blame] | 221 | int err = ccid_hc_tx_send_packet(dp->dccps_hc_tx_ccid, sk, skb, |
| 222 | skb->len); |
| 223 | |
| 224 | if (err > 0) |
| 225 | err = dccp_wait_for_ccid(sk, skb, timeo); |
Arnaldo Carvalho de Melo | 27258ee | 2005-08-09 20:30:56 -0700 | [diff] [blame] | 226 | |
| 227 | if (err == 0) { |
Arnaldo Carvalho de Melo | 27258ee | 2005-08-09 20:30:56 -0700 | [diff] [blame] | 228 | struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb); |
Arnaldo Carvalho de Melo | d6809c1 | 2005-08-27 03:06:35 -0300 | [diff] [blame] | 229 | const int len = skb->len; |
Arnaldo Carvalho de Melo | 27258ee | 2005-08-09 20:30:56 -0700 | [diff] [blame] | 230 | |
| 231 | if (sk->sk_state == DCCP_PARTOPEN) { |
| 232 | /* See 8.1.5. Handshake Completion */ |
| 233 | inet_csk_schedule_ack(sk); |
| 234 | inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK, |
| 235 | inet_csk(sk)->icsk_rto, |
| 236 | DCCP_RTO_MAX); |
| 237 | dcb->dccpd_type = DCCP_PKT_DATAACK; |
Arnaldo Carvalho de Melo | ae31c33 | 2005-09-18 00:17:51 -0700 | [diff] [blame] | 238 | } else if (dccp_ack_pending(sk)) |
Arnaldo Carvalho de Melo | 27258ee | 2005-08-09 20:30:56 -0700 | [diff] [blame] | 239 | dcb->dccpd_type = DCCP_PKT_DATAACK; |
| 240 | else |
| 241 | dcb->dccpd_type = DCCP_PKT_DATA; |
| 242 | |
| 243 | err = dccp_transmit_skb(sk, skb); |
| 244 | ccid_hc_tx_packet_sent(dp->dccps_hc_tx_ccid, sk, 0, len); |
Herbert Xu | ffa2934 | 2005-10-16 21:08:46 +1000 | [diff] [blame] | 245 | } else |
| 246 | kfree_skb(skb); |
Arnaldo Carvalho de Melo | 27258ee | 2005-08-09 20:30:56 -0700 | [diff] [blame] | 247 | |
| 248 | return err; |
| 249 | } |
| 250 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 251 | int dccp_retransmit_skb(struct sock *sk, struct sk_buff *skb) |
| 252 | { |
| 253 | if (inet_sk_rebuild_header(sk) != 0) |
| 254 | return -EHOSTUNREACH; /* Routing failure or similar. */ |
| 255 | |
| 256 | return dccp_transmit_skb(sk, (skb_cloned(skb) ? |
| 257 | pskb_copy(skb, GFP_ATOMIC): |
| 258 | skb_clone(skb, GFP_ATOMIC))); |
| 259 | } |
| 260 | |
| 261 | struct sk_buff *dccp_make_response(struct sock *sk, struct dst_entry *dst, |
| 262 | struct request_sock *req) |
| 263 | { |
| 264 | struct dccp_hdr *dh; |
Arnaldo Carvalho de Melo | 67e6b62 | 2005-09-16 16:58:40 -0700 | [diff] [blame] | 265 | struct dccp_request_sock *dreq; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 266 | const int dccp_header_size = sizeof(struct dccp_hdr) + |
| 267 | sizeof(struct dccp_hdr_ext) + |
| 268 | sizeof(struct dccp_hdr_response); |
| 269 | struct sk_buff *skb = sock_wmalloc(sk, MAX_HEADER + DCCP_MAX_OPT_LEN + |
| 270 | dccp_header_size, 1, |
| 271 | GFP_ATOMIC); |
| 272 | if (skb == NULL) |
| 273 | return NULL; |
| 274 | |
| 275 | /* Reserve space for headers. */ |
| 276 | skb_reserve(skb, MAX_HEADER + DCCP_MAX_OPT_LEN + dccp_header_size); |
| 277 | |
| 278 | skb->dst = dst_clone(dst); |
| 279 | skb->csum = 0; |
| 280 | |
Arnaldo Carvalho de Melo | 67e6b62 | 2005-09-16 16:58:40 -0700 | [diff] [blame] | 281 | dreq = dccp_rsk(req); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 282 | DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_RESPONSE; |
Arnaldo Carvalho de Melo | 67e6b62 | 2005-09-16 16:58:40 -0700 | [diff] [blame] | 283 | DCCP_SKB_CB(skb)->dccpd_seq = dreq->dreq_iss; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 284 | dccp_insert_options(sk, skb); |
| 285 | |
| 286 | skb->h.raw = skb_push(skb, dccp_header_size); |
| 287 | |
| 288 | dh = dccp_hdr(skb); |
| 289 | memset(dh, 0, dccp_header_size); |
| 290 | |
| 291 | dh->dccph_sport = inet_sk(sk)->sport; |
| 292 | dh->dccph_dport = inet_rsk(req)->rmt_port; |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 293 | dh->dccph_doff = (dccp_header_size + |
| 294 | DCCP_SKB_CB(skb)->dccpd_opt_len) / 4; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 295 | dh->dccph_type = DCCP_PKT_RESPONSE; |
| 296 | dh->dccph_x = 1; |
Arnaldo Carvalho de Melo | 67e6b62 | 2005-09-16 16:58:40 -0700 | [diff] [blame] | 297 | dccp_hdr_set_seq(dh, dreq->dreq_iss); |
| 298 | dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), dreq->dreq_isr); |
| 299 | dccp_hdr_response(skb)->dccph_resp_service = dreq->dreq_service; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 300 | |
Yoshifumi Nishida | 95b81ef | 2005-08-09 20:15:35 -0700 | [diff] [blame] | 301 | dh->dccph_checksum = dccp_v4_checksum(skb, inet_rsk(req)->loc_addr, |
| 302 | inet_rsk(req)->rmt_addr); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 303 | |
| 304 | DCCP_INC_STATS(DCCP_MIB_OUTSEGS); |
| 305 | return skb; |
| 306 | } |
| 307 | |
| 308 | struct sk_buff *dccp_make_reset(struct sock *sk, struct dst_entry *dst, |
| 309 | const enum dccp_reset_codes code) |
| 310 | |
| 311 | { |
| 312 | struct dccp_hdr *dh; |
| 313 | struct dccp_sock *dp = dccp_sk(sk); |
| 314 | const int dccp_header_size = sizeof(struct dccp_hdr) + |
| 315 | sizeof(struct dccp_hdr_ext) + |
| 316 | sizeof(struct dccp_hdr_reset); |
| 317 | struct sk_buff *skb = sock_wmalloc(sk, MAX_HEADER + DCCP_MAX_OPT_LEN + |
| 318 | dccp_header_size, 1, |
| 319 | GFP_ATOMIC); |
| 320 | if (skb == NULL) |
| 321 | return NULL; |
| 322 | |
| 323 | /* Reserve space for headers. */ |
| 324 | skb_reserve(skb, MAX_HEADER + DCCP_MAX_OPT_LEN + dccp_header_size); |
| 325 | |
| 326 | skb->dst = dst_clone(dst); |
| 327 | skb->csum = 0; |
| 328 | |
| 329 | dccp_inc_seqno(&dp->dccps_gss); |
| 330 | |
| 331 | DCCP_SKB_CB(skb)->dccpd_reset_code = code; |
| 332 | DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_RESET; |
| 333 | DCCP_SKB_CB(skb)->dccpd_seq = dp->dccps_gss; |
| 334 | dccp_insert_options(sk, skb); |
| 335 | |
| 336 | skb->h.raw = skb_push(skb, dccp_header_size); |
| 337 | |
| 338 | dh = dccp_hdr(skb); |
| 339 | memset(dh, 0, dccp_header_size); |
| 340 | |
| 341 | dh->dccph_sport = inet_sk(sk)->sport; |
| 342 | dh->dccph_dport = inet_sk(sk)->dport; |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 343 | dh->dccph_doff = (dccp_header_size + |
| 344 | DCCP_SKB_CB(skb)->dccpd_opt_len) / 4; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 345 | dh->dccph_type = DCCP_PKT_RESET; |
| 346 | dh->dccph_x = 1; |
| 347 | dccp_hdr_set_seq(dh, dp->dccps_gss); |
| 348 | dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), dp->dccps_gsr); |
| 349 | |
| 350 | dccp_hdr_reset(skb)->dccph_reset_code = code; |
| 351 | |
Yoshifumi Nishida | 95b81ef | 2005-08-09 20:15:35 -0700 | [diff] [blame] | 352 | dh->dccph_checksum = dccp_v4_checksum(skb, inet_sk(sk)->saddr, |
| 353 | inet_sk(sk)->daddr); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 354 | |
| 355 | DCCP_INC_STATS(DCCP_MIB_OUTSEGS); |
| 356 | return skb; |
| 357 | } |
| 358 | |
| 359 | /* |
| 360 | * Do all connect socket setups that can be done AF independent. |
| 361 | */ |
| 362 | static inline void dccp_connect_init(struct sock *sk) |
| 363 | { |
| 364 | struct dst_entry *dst = __sk_dst_get(sk); |
| 365 | struct inet_connection_sock *icsk = inet_csk(sk); |
| 366 | |
| 367 | sk->sk_err = 0; |
| 368 | sock_reset_flag(sk, SOCK_DONE); |
| 369 | |
| 370 | dccp_sync_mss(sk, dst_mtu(dst)); |
| 371 | |
| 372 | /* |
| 373 | * FIXME: set dp->{dccps_swh,dccps_swl}, with |
| 374 | * something like dccp_inc_seq |
| 375 | */ |
| 376 | |
| 377 | icsk->icsk_retransmits = 0; |
| 378 | } |
| 379 | |
| 380 | int dccp_connect(struct sock *sk) |
| 381 | { |
| 382 | struct sk_buff *skb; |
| 383 | struct inet_connection_sock *icsk = inet_csk(sk); |
| 384 | |
| 385 | dccp_connect_init(sk); |
| 386 | |
| 387 | skb = alloc_skb(MAX_DCCP_HEADER + 15, sk->sk_allocation); |
| 388 | if (unlikely(skb == NULL)) |
| 389 | return -ENOBUFS; |
| 390 | |
| 391 | /* Reserve space for headers. */ |
| 392 | skb_reserve(skb, MAX_DCCP_HEADER); |
| 393 | |
| 394 | DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_REQUEST; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 395 | skb->csum = 0; |
| 396 | skb_set_owner_w(skb, sk); |
| 397 | |
| 398 | BUG_TRAP(sk->sk_send_head == NULL); |
| 399 | sk->sk_send_head = skb; |
| 400 | dccp_transmit_skb(sk, skb_clone(skb, GFP_KERNEL)); |
| 401 | DCCP_INC_STATS(DCCP_MIB_ACTIVEOPENS); |
| 402 | |
| 403 | /* Timer for repeating the REQUEST until an answer. */ |
Arnaldo Carvalho de Melo | 27258ee | 2005-08-09 20:30:56 -0700 | [diff] [blame] | 404 | inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, |
| 405 | icsk->icsk_rto, DCCP_RTO_MAX); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 406 | return 0; |
| 407 | } |
| 408 | |
| 409 | void dccp_send_ack(struct sock *sk) |
| 410 | { |
| 411 | /* If we have been reset, we may not send again. */ |
| 412 | if (sk->sk_state != DCCP_CLOSED) { |
| 413 | struct sk_buff *skb = alloc_skb(MAX_DCCP_HEADER, GFP_ATOMIC); |
| 414 | |
| 415 | if (skb == NULL) { |
| 416 | inet_csk_schedule_ack(sk); |
| 417 | inet_csk(sk)->icsk_ack.ato = TCP_ATO_MIN; |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 418 | inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK, |
| 419 | TCP_DELACK_MAX, |
| 420 | DCCP_RTO_MAX); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 421 | return; |
| 422 | } |
| 423 | |
| 424 | /* Reserve space for headers */ |
| 425 | skb_reserve(skb, MAX_DCCP_HEADER); |
| 426 | skb->csum = 0; |
| 427 | DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_ACK; |
| 428 | skb_set_owner_w(skb, sk); |
| 429 | dccp_transmit_skb(sk, skb); |
| 430 | } |
| 431 | } |
| 432 | |
| 433 | EXPORT_SYMBOL_GPL(dccp_send_ack); |
| 434 | |
| 435 | void dccp_send_delayed_ack(struct sock *sk) |
| 436 | { |
| 437 | struct inet_connection_sock *icsk = inet_csk(sk); |
| 438 | /* |
| 439 | * FIXME: tune this timer. elapsed time fixes the skew, so no problem |
| 440 | * with using 2s, and active senders also piggyback the ACK into a |
| 441 | * DATAACK packet, so this is really for quiescent senders. |
| 442 | */ |
| 443 | unsigned long timeout = jiffies + 2 * HZ; |
| 444 | |
| 445 | /* Use new timeout only if there wasn't a older one earlier. */ |
| 446 | if (icsk->icsk_ack.pending & ICSK_ACK_TIMER) { |
| 447 | /* If delack timer was blocked or is about to expire, |
| 448 | * send ACK now. |
| 449 | * |
| 450 | * FIXME: check the "about to expire" part |
| 451 | */ |
| 452 | if (icsk->icsk_ack.blocked) { |
| 453 | dccp_send_ack(sk); |
| 454 | return; |
| 455 | } |
| 456 | |
| 457 | if (!time_before(timeout, icsk->icsk_ack.timeout)) |
| 458 | timeout = icsk->icsk_ack.timeout; |
| 459 | } |
| 460 | icsk->icsk_ack.pending |= ICSK_ACK_SCHED | ICSK_ACK_TIMER; |
| 461 | icsk->icsk_ack.timeout = timeout; |
| 462 | sk_reset_timer(sk, &icsk->icsk_delack_timer, timeout); |
| 463 | } |
| 464 | |
Arnaldo Carvalho de Melo | e92ae93 | 2005-08-17 03:10:59 -0300 | [diff] [blame] | 465 | void dccp_send_sync(struct sock *sk, const u64 seq, |
| 466 | const enum dccp_pkt_type pkt_type) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 467 | { |
| 468 | /* |
| 469 | * We are not putting this on the write queue, so |
| 470 | * dccp_transmit_skb() will set the ownership to this |
| 471 | * sock. |
| 472 | */ |
| 473 | struct sk_buff *skb = alloc_skb(MAX_DCCP_HEADER, GFP_ATOMIC); |
| 474 | |
| 475 | if (skb == NULL) |
| 476 | /* FIXME: how to make sure the sync is sent? */ |
| 477 | return; |
| 478 | |
| 479 | /* Reserve space for headers and prepare control bits. */ |
| 480 | skb_reserve(skb, MAX_DCCP_HEADER); |
| 481 | skb->csum = 0; |
Arnaldo Carvalho de Melo | e92ae93 | 2005-08-17 03:10:59 -0300 | [diff] [blame] | 482 | DCCP_SKB_CB(skb)->dccpd_type = pkt_type; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 483 | DCCP_SKB_CB(skb)->dccpd_seq = seq; |
| 484 | |
| 485 | skb_set_owner_w(skb, sk); |
| 486 | dccp_transmit_skb(sk, skb); |
| 487 | } |
| 488 | |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 489 | /* |
| 490 | * Send a DCCP_PKT_CLOSE/CLOSEREQ. The caller locks the socket for us. This |
| 491 | * cannot be allowed to fail queueing a DCCP_PKT_CLOSE/CLOSEREQ frame under |
| 492 | * any circumstances. |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 493 | */ |
Arnaldo Carvalho de Melo | 7ad07e7 | 2005-08-23 21:50:06 -0700 | [diff] [blame] | 494 | void dccp_send_close(struct sock *sk, const int active) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 495 | { |
| 496 | struct dccp_sock *dp = dccp_sk(sk); |
| 497 | struct sk_buff *skb; |
Al Viro | 7d877f3 | 2005-10-21 03:20:43 -0400 | [diff] [blame] | 498 | const gfp_t prio = active ? GFP_KERNEL : GFP_ATOMIC; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 499 | |
Arnaldo Carvalho de Melo | 7ad07e7 | 2005-08-23 21:50:06 -0700 | [diff] [blame] | 500 | skb = alloc_skb(sk->sk_prot->max_header, prio); |
| 501 | if (skb == NULL) |
| 502 | return; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 503 | |
| 504 | /* Reserve space for headers and prepare control bits. */ |
| 505 | skb_reserve(skb, sk->sk_prot->max_header); |
| 506 | skb->csum = 0; |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 507 | DCCP_SKB_CB(skb)->dccpd_type = dp->dccps_role == DCCP_ROLE_CLIENT ? |
| 508 | DCCP_PKT_CLOSE : DCCP_PKT_CLOSEREQ; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 509 | |
| 510 | skb_set_owner_w(skb, sk); |
Arnaldo Carvalho de Melo | 7ad07e7 | 2005-08-23 21:50:06 -0700 | [diff] [blame] | 511 | if (active) { |
| 512 | BUG_TRAP(sk->sk_send_head == NULL); |
| 513 | sk->sk_send_head = skb; |
| 514 | dccp_transmit_skb(sk, skb_clone(skb, prio)); |
| 515 | } else |
| 516 | dccp_transmit_skb(sk, skb); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 517 | } |