Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 1 | /* |
| 2 | * net/dccp/output.c |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 3 | * |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 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> |
Herbert Xu | 48918a4 | 2005-10-30 11:20:59 +1100 | [diff] [blame] | 14 | #include <linux/kernel.h> |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 15 | #include <linux/skbuff.h> |
| 16 | |
Arnaldo Carvalho de Melo | 14c8502 | 2005-12-27 02:43:12 -0200 | [diff] [blame] | 17 | #include <net/inet_sock.h> |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 18 | #include <net/sock.h> |
| 19 | |
Arnaldo Carvalho de Melo | ae31c33 | 2005-09-18 00:17:51 -0700 | [diff] [blame] | 20 | #include "ackvec.h" |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 21 | #include "ccid.h" |
| 22 | #include "dccp.h" |
| 23 | |
| 24 | static inline void dccp_event_ack_sent(struct sock *sk) |
| 25 | { |
| 26 | inet_csk_clear_xmit_timer(sk, ICSK_TIME_DACK); |
| 27 | } |
| 28 | |
Arnaldo Carvalho de Melo | c25a18b | 2006-03-20 21:58:56 -0800 | [diff] [blame] | 29 | static void dccp_skb_entail(struct sock *sk, struct sk_buff *skb) |
Herbert Xu | 48918a4 | 2005-10-30 11:20:59 +1100 | [diff] [blame] | 30 | { |
| 31 | skb_set_owner_w(skb, sk); |
| 32 | WARN_ON(sk->sk_send_head); |
| 33 | sk->sk_send_head = skb; |
| 34 | } |
| 35 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 36 | /* |
| 37 | * All SKB's seen here are completely headerless. It is our |
| 38 | * job to build the DCCP header, and pass the packet down to |
| 39 | * IP so it can do the same plus pass the packet off to the |
| 40 | * device. |
| 41 | */ |
Herbert Xu | 48918a4 | 2005-10-30 11:20:59 +1100 | [diff] [blame] | 42 | static int dccp_transmit_skb(struct sock *sk, struct sk_buff *skb) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 43 | { |
| 44 | if (likely(skb != NULL)) { |
| 45 | const struct inet_sock *inet = inet_sk(sk); |
Arnaldo Carvalho de Melo | 57cca05 | 2005-12-13 23:16:16 -0800 | [diff] [blame] | 46 | const struct inet_connection_sock *icsk = inet_csk(sk); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 47 | struct dccp_sock *dp = dccp_sk(sk); |
| 48 | struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb); |
| 49 | struct dccp_hdr *dh; |
| 50 | /* XXX For now we're using only 48 bits sequence numbers */ |
Arnaldo Carvalho de Melo | 118b2c9 | 2006-03-20 22:31:09 -0800 | [diff] [blame] | 51 | const u32 dccp_header_size = sizeof(*dh) + |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 52 | sizeof(struct dccp_hdr_ext) + |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 53 | dccp_packet_hdr_len(dcb->dccpd_type); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 54 | int err, set_ack = 1; |
| 55 | u64 ackno = dp->dccps_gsr; |
| 56 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 57 | dccp_inc_seqno(&dp->dccps_gss); |
| 58 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 59 | switch (dcb->dccpd_type) { |
| 60 | case DCCP_PKT_DATA: |
| 61 | set_ack = 0; |
Herbert Xu | edc9e81 | 2005-10-30 11:20:59 +1100 | [diff] [blame] | 62 | /* fall through */ |
| 63 | case DCCP_PKT_DATAACK: |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 64 | break; |
Herbert Xu | edc9e81 | 2005-10-30 11:20:59 +1100 | [diff] [blame] | 65 | |
Andrea Bittau | afe0025 | 2006-03-20 17:43:56 -0800 | [diff] [blame] | 66 | case DCCP_PKT_REQUEST: |
| 67 | set_ack = 0; |
| 68 | /* fall through */ |
| 69 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 70 | case DCCP_PKT_SYNC: |
| 71 | case DCCP_PKT_SYNCACK: |
| 72 | ackno = dcb->dccpd_seq; |
Herbert Xu | edc9e81 | 2005-10-30 11:20:59 +1100 | [diff] [blame] | 73 | /* fall through */ |
| 74 | default: |
| 75 | /* |
| 76 | * Only data packets should come through with skb->sk |
| 77 | * set. |
| 78 | */ |
| 79 | WARN_ON(skb->sk); |
| 80 | skb_set_owner_w(skb, sk); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 81 | break; |
| 82 | } |
Arnaldo Carvalho de Melo | 2411772 | 2005-08-21 05:40:16 -0300 | [diff] [blame] | 83 | |
| 84 | dcb->dccpd_seq = dp->dccps_gss; |
Arnaldo Carvalho de Melo | 2d0817d | 2006-03-20 22:32:06 -0800 | [diff] [blame] | 85 | |
| 86 | if (dccp_insert_options(sk, skb)) { |
| 87 | kfree_skb(skb); |
| 88 | return -EPROTO; |
| 89 | } |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 90 | |
Herbert Xu | fda0fd6 | 2005-10-14 16:38:49 +1000 | [diff] [blame] | 91 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 92 | /* Build DCCP header and checksum it. */ |
Gerrit Renker | 9b42078 | 2006-11-10 11:22:32 -0200 | [diff] [blame] | 93 | dh = dccp_zeroed_hdr(skb, dccp_header_size); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 94 | dh->dccph_type = dcb->dccpd_type; |
| 95 | dh->dccph_sport = inet->sport; |
| 96 | dh->dccph_dport = inet->dport; |
| 97 | dh->dccph_doff = (dccp_header_size + dcb->dccpd_opt_len) / 4; |
| 98 | dh->dccph_ccval = dcb->dccpd_ccval; |
Gerrit Renker | 6f4e5ff | 2006-11-10 17:43:06 -0200 | [diff] [blame] | 99 | dh->dccph_cscov = dp->dccps_pcslen; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 100 | /* XXX For now we're using only 48 bits sequence numbers */ |
| 101 | dh->dccph_x = 1; |
| 102 | |
| 103 | dp->dccps_awh = dp->dccps_gss; |
| 104 | dccp_hdr_set_seq(dh, dp->dccps_gss); |
| 105 | if (set_ack) |
| 106 | dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), ackno); |
| 107 | |
| 108 | switch (dcb->dccpd_type) { |
| 109 | case DCCP_PKT_REQUEST: |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 110 | dccp_hdr_request(skb)->dccph_req_service = |
Arnaldo Carvalho de Melo | 67e6b62 | 2005-09-16 16:58:40 -0700 | [diff] [blame] | 111 | dp->dccps_service; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 112 | break; |
| 113 | case DCCP_PKT_RESET: |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 114 | dccp_hdr_reset(skb)->dccph_reset_code = |
| 115 | dcb->dccpd_reset_code; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 116 | break; |
| 117 | } |
| 118 | |
Gerrit Renker | 6f4e5ff | 2006-11-10 17:43:06 -0200 | [diff] [blame] | 119 | icsk->icsk_af_ops->send_check(sk, 0, skb); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 120 | |
Arnaldo Carvalho de Melo | 7ad07e7 | 2005-08-23 21:50:06 -0700 | [diff] [blame] | 121 | if (set_ack) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 122 | dccp_event_ack_sent(sk); |
| 123 | |
| 124 | DCCP_INC_STATS(DCCP_MIB_OUTSEGS); |
| 125 | |
Herbert Xu | 49c5bfa | 2005-10-18 12:03:28 +1000 | [diff] [blame] | 126 | memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); |
David S. Miller | e89862f | 2007-01-26 01:04:55 -0800 | [diff] [blame] | 127 | err = icsk->icsk_af_ops->queue_xmit(skb, 0); |
Gerrit Renker | b9df3cb | 2006-11-14 11:21:36 -0200 | [diff] [blame] | 128 | return net_xmit_eval(err); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 129 | } |
| 130 | return -ENOBUFS; |
| 131 | } |
| 132 | |
| 133 | unsigned int dccp_sync_mss(struct sock *sk, u32 pmtu) |
| 134 | { |
Arnaldo Carvalho de Melo | d83d846 | 2005-12-13 23:26:10 -0800 | [diff] [blame] | 135 | struct inet_connection_sock *icsk = inet_csk(sk); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 136 | struct dccp_sock *dp = dccp_sk(sk); |
Arnaldo Carvalho de Melo | d83d846 | 2005-12-13 23:26:10 -0800 | [diff] [blame] | 137 | int mss_now = (pmtu - icsk->icsk_af_ops->net_header_len - |
Arnaldo Carvalho de Melo | 57cca05 | 2005-12-13 23:16:16 -0800 | [diff] [blame] | 138 | sizeof(struct dccp_hdr) - sizeof(struct dccp_hdr_ext)); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 139 | |
| 140 | /* Now subtract optional transport overhead */ |
Arnaldo Carvalho de Melo | d83d846 | 2005-12-13 23:26:10 -0800 | [diff] [blame] | 141 | mss_now -= icsk->icsk_ext_hdr_len; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 142 | |
| 143 | /* |
| 144 | * FIXME: this should come from the CCID infrastructure, where, say, |
| 145 | * TFRC will say it wants TIMESTAMPS, ELAPSED time, etc, for now lets |
| 146 | * put a rough estimate for NDP + TIMESTAMP + TIMESTAMP_ECHO + ELAPSED |
| 147 | * TIME + TFRC_OPT_LOSS_EVENT_RATE + TFRC_OPT_RECEIVE_RATE + padding to |
| 148 | * make it a multiple of 4 |
| 149 | */ |
| 150 | |
| 151 | mss_now -= ((5 + 6 + 10 + 6 + 6 + 6 + 3) / 4) * 4; |
| 152 | |
| 153 | /* And store cached results */ |
Arnaldo Carvalho de Melo | d83d846 | 2005-12-13 23:26:10 -0800 | [diff] [blame] | 154 | icsk->icsk_pmtu_cookie = pmtu; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 155 | dp->dccps_mss_cache = mss_now; |
| 156 | |
| 157 | return mss_now; |
| 158 | } |
| 159 | |
Arnaldo Carvalho de Melo | f21e68c | 2005-12-13 23:24:16 -0800 | [diff] [blame] | 160 | EXPORT_SYMBOL_GPL(dccp_sync_mss); |
| 161 | |
Arnaldo Carvalho de Melo | c530cfb | 2005-08-29 02:15:54 -0300 | [diff] [blame] | 162 | void dccp_write_space(struct sock *sk) |
| 163 | { |
| 164 | read_lock(&sk->sk_callback_lock); |
| 165 | |
| 166 | if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) |
| 167 | wake_up_interruptible(sk->sk_sleep); |
| 168 | /* Should agree with poll, otherwise some programs break */ |
| 169 | if (sock_writeable(sk)) |
| 170 | sk_wake_async(sk, 2, POLL_OUT); |
| 171 | |
| 172 | read_unlock(&sk->sk_callback_lock); |
| 173 | } |
| 174 | |
Arnaldo Carvalho de Melo | d6809c1 | 2005-08-27 03:06:35 -0300 | [diff] [blame] | 175 | /** |
| 176 | * dccp_wait_for_ccid - Wait for ccid to tell us we can send a packet |
| 177 | * @sk: socket to wait for |
Arnaldo Carvalho de Melo | d6809c1 | 2005-08-27 03:06:35 -0300 | [diff] [blame] | 178 | */ |
Ian McDonald | 5cc3741d | 2006-12-09 23:56:09 -0200 | [diff] [blame] | 179 | static int dccp_wait_for_ccid(struct sock *sk, struct sk_buff *skb) |
Arnaldo Carvalho de Melo | d6809c1 | 2005-08-27 03:06:35 -0300 | [diff] [blame] | 180 | { |
| 181 | struct dccp_sock *dp = dccp_sk(sk); |
| 182 | DEFINE_WAIT(wait); |
Ian McDonald | 5cc3741d | 2006-12-09 23:56:09 -0200 | [diff] [blame] | 183 | unsigned long delay; |
Arnaldo Carvalho de Melo | d6809c1 | 2005-08-27 03:06:35 -0300 | [diff] [blame] | 184 | int rc; |
| 185 | |
| 186 | while (1) { |
| 187 | prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE); |
| 188 | |
Ian McDonald | 97e5848 | 2006-08-26 19:16:45 -0700 | [diff] [blame] | 189 | if (sk->sk_err) |
Arnaldo Carvalho de Melo | d6809c1 | 2005-08-27 03:06:35 -0300 | [diff] [blame] | 190 | goto do_error; |
Arnaldo Carvalho de Melo | d6809c1 | 2005-08-27 03:06:35 -0300 | [diff] [blame] | 191 | if (signal_pending(current)) |
| 192 | goto do_interrupted; |
| 193 | |
Gerrit Renker | 6b57c93 | 2006-11-28 19:55:06 -0200 | [diff] [blame] | 194 | rc = ccid_hc_tx_send_packet(dp->dccps_hc_tx_ccid, sk, skb); |
Arnaldo Carvalho de Melo | d6809c1 | 2005-08-27 03:06:35 -0300 | [diff] [blame] | 195 | if (rc <= 0) |
| 196 | break; |
| 197 | delay = msecs_to_jiffies(rc); |
Arnaldo Carvalho de Melo | d6809c1 | 2005-08-27 03:06:35 -0300 | [diff] [blame] | 198 | sk->sk_write_pending++; |
| 199 | release_sock(sk); |
Ian McDonald | 5cc3741d | 2006-12-09 23:56:09 -0200 | [diff] [blame] | 200 | schedule_timeout(delay); |
Arnaldo Carvalho de Melo | d6809c1 | 2005-08-27 03:06:35 -0300 | [diff] [blame] | 201 | lock_sock(sk); |
| 202 | sk->sk_write_pending--; |
| 203 | } |
| 204 | out: |
| 205 | finish_wait(sk->sk_sleep, &wait); |
| 206 | return rc; |
| 207 | |
| 208 | do_error: |
| 209 | rc = -EPIPE; |
| 210 | goto out; |
Arnaldo Carvalho de Melo | d6809c1 | 2005-08-27 03:06:35 -0300 | [diff] [blame] | 211 | do_interrupted: |
Ian McDonald | 5cc3741d | 2006-12-09 23:56:09 -0200 | [diff] [blame] | 212 | rc = -EINTR; |
Arnaldo Carvalho de Melo | d6809c1 | 2005-08-27 03:06:35 -0300 | [diff] [blame] | 213 | goto out; |
| 214 | } |
| 215 | |
Ian McDonald | 97e5848 | 2006-08-26 19:16:45 -0700 | [diff] [blame] | 216 | static void dccp_write_xmit_timer(unsigned long data) { |
| 217 | struct sock *sk = (struct sock *)data; |
| 218 | struct dccp_sock *dp = dccp_sk(sk); |
| 219 | |
| 220 | bh_lock_sock(sk); |
| 221 | if (sock_owned_by_user(sk)) |
| 222 | sk_reset_timer(sk, &dp->dccps_xmit_timer, jiffies+1); |
| 223 | else |
| 224 | dccp_write_xmit(sk, 0); |
| 225 | bh_unlock_sock(sk); |
| 226 | sock_put(sk); |
| 227 | } |
| 228 | |
| 229 | void dccp_write_xmit(struct sock *sk, int block) |
Arnaldo Carvalho de Melo | 27258ee | 2005-08-09 20:30:56 -0700 | [diff] [blame] | 230 | { |
Ian McDonald | 97e5848 | 2006-08-26 19:16:45 -0700 | [diff] [blame] | 231 | struct dccp_sock *dp = dccp_sk(sk); |
| 232 | struct sk_buff *skb; |
Ian McDonald | 97e5848 | 2006-08-26 19:16:45 -0700 | [diff] [blame] | 233 | |
| 234 | while ((skb = skb_peek(&sk->sk_write_queue))) { |
Gerrit Renker | 6b57c93 | 2006-11-28 19:55:06 -0200 | [diff] [blame] | 235 | int err = ccid_hc_tx_send_packet(dp->dccps_hc_tx_ccid, sk, skb); |
Arnaldo Carvalho de Melo | d6809c1 | 2005-08-27 03:06:35 -0300 | [diff] [blame] | 236 | |
Ian McDonald | 97e5848 | 2006-08-26 19:16:45 -0700 | [diff] [blame] | 237 | if (err > 0) { |
| 238 | if (!block) { |
| 239 | sk_reset_timer(sk, &dp->dccps_xmit_timer, |
| 240 | msecs_to_jiffies(err)+jiffies); |
| 241 | break; |
Ian McDonald | 5cc3741d | 2006-12-09 23:56:09 -0200 | [diff] [blame] | 242 | } else |
| 243 | err = dccp_wait_for_ccid(sk, skb); |
Gerrit Renker | f6282f4 | 2006-12-10 00:05:12 -0200 | [diff] [blame] | 244 | if (err && err != -EINTR) |
Gerrit Renker | 59348b1 | 2006-11-20 18:39:23 -0200 | [diff] [blame] | 245 | DCCP_BUG("err=%d after dccp_wait_for_ccid", err); |
Ian McDonald | 97e5848 | 2006-08-26 19:16:45 -0700 | [diff] [blame] | 246 | } |
Arnaldo Carvalho de Melo | 27258ee | 2005-08-09 20:30:56 -0700 | [diff] [blame] | 247 | |
Ian McDonald | 97e5848 | 2006-08-26 19:16:45 -0700 | [diff] [blame] | 248 | skb_dequeue(&sk->sk_write_queue); |
| 249 | if (err == 0) { |
| 250 | struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb); |
| 251 | const int len = skb->len; |
Arnaldo Carvalho de Melo | 27258ee | 2005-08-09 20:30:56 -0700 | [diff] [blame] | 252 | |
Ian McDonald | 97e5848 | 2006-08-26 19:16:45 -0700 | [diff] [blame] | 253 | if (sk->sk_state == DCCP_PARTOPEN) { |
| 254 | /* See 8.1.5. Handshake Completion */ |
| 255 | inet_csk_schedule_ack(sk); |
| 256 | inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK, |
Arnaldo Carvalho de Melo | 27258ee | 2005-08-09 20:30:56 -0700 | [diff] [blame] | 257 | inet_csk(sk)->icsk_rto, |
| 258 | DCCP_RTO_MAX); |
Ian McDonald | 97e5848 | 2006-08-26 19:16:45 -0700 | [diff] [blame] | 259 | dcb->dccpd_type = DCCP_PKT_DATAACK; |
| 260 | } else if (dccp_ack_pending(sk)) |
| 261 | dcb->dccpd_type = DCCP_PKT_DATAACK; |
| 262 | else |
| 263 | dcb->dccpd_type = DCCP_PKT_DATA; |
Arnaldo Carvalho de Melo | 27258ee | 2005-08-09 20:30:56 -0700 | [diff] [blame] | 264 | |
Ian McDonald | 97e5848 | 2006-08-26 19:16:45 -0700 | [diff] [blame] | 265 | err = dccp_transmit_skb(sk, skb); |
| 266 | ccid_hc_tx_packet_sent(dp->dccps_hc_tx_ccid, sk, 0, len); |
Gerrit Renker | 59348b1 | 2006-11-20 18:39:23 -0200 | [diff] [blame] | 267 | if (err) |
| 268 | DCCP_BUG("err=%d after ccid_hc_tx_packet_sent", |
| 269 | err); |
Gerrit Renker | f6282f4 | 2006-12-10 00:05:12 -0200 | [diff] [blame] | 270 | } else { |
| 271 | dccp_pr_debug("packet discarded\n"); |
Ian McDonald | 97e5848 | 2006-08-26 19:16:45 -0700 | [diff] [blame] | 272 | kfree(skb); |
Gerrit Renker | f6282f4 | 2006-12-10 00:05:12 -0200 | [diff] [blame] | 273 | } |
Ian McDonald | 97e5848 | 2006-08-26 19:16:45 -0700 | [diff] [blame] | 274 | } |
Arnaldo Carvalho de Melo | 27258ee | 2005-08-09 20:30:56 -0700 | [diff] [blame] | 275 | } |
| 276 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 277 | int dccp_retransmit_skb(struct sock *sk, struct sk_buff *skb) |
| 278 | { |
Arnaldo Carvalho de Melo | 57cca05 | 2005-12-13 23:16:16 -0800 | [diff] [blame] | 279 | if (inet_csk(sk)->icsk_af_ops->rebuild_header(sk) != 0) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 280 | return -EHOSTUNREACH; /* Routing failure or similar. */ |
| 281 | |
| 282 | return dccp_transmit_skb(sk, (skb_cloned(skb) ? |
| 283 | pskb_copy(skb, GFP_ATOMIC): |
| 284 | skb_clone(skb, GFP_ATOMIC))); |
| 285 | } |
| 286 | |
| 287 | struct sk_buff *dccp_make_response(struct sock *sk, struct dst_entry *dst, |
| 288 | struct request_sock *req) |
| 289 | { |
| 290 | struct dccp_hdr *dh; |
Arnaldo Carvalho de Melo | 67e6b62 | 2005-09-16 16:58:40 -0700 | [diff] [blame] | 291 | struct dccp_request_sock *dreq; |
Arnaldo Carvalho de Melo | 118b2c9 | 2006-03-20 22:31:09 -0800 | [diff] [blame] | 292 | const u32 dccp_header_size = sizeof(struct dccp_hdr) + |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 293 | sizeof(struct dccp_hdr_ext) + |
| 294 | sizeof(struct dccp_hdr_response); |
Arnaldo Carvalho de Melo | 118b2c9 | 2006-03-20 22:31:09 -0800 | [diff] [blame] | 295 | struct sk_buff *skb = sock_wmalloc(sk, sk->sk_prot->max_header, 1, |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 296 | GFP_ATOMIC); |
| 297 | if (skb == NULL) |
| 298 | return NULL; |
| 299 | |
| 300 | /* Reserve space for headers. */ |
Arnaldo Carvalho de Melo | 118b2c9 | 2006-03-20 22:31:09 -0800 | [diff] [blame] | 301 | skb_reserve(skb, sk->sk_prot->max_header); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 302 | |
| 303 | skb->dst = dst_clone(dst); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 304 | |
Arnaldo Carvalho de Melo | 67e6b62 | 2005-09-16 16:58:40 -0700 | [diff] [blame] | 305 | dreq = dccp_rsk(req); |
Gerrit Renker | e11d9d3 | 2006-11-13 13:12:07 -0200 | [diff] [blame] | 306 | if (inet_rsk(req)->acked) /* increase ISS upon retransmission */ |
| 307 | dccp_inc_seqno(&dreq->dreq_iss); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 308 | DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_RESPONSE; |
Arnaldo Carvalho de Melo | 67e6b62 | 2005-09-16 16:58:40 -0700 | [diff] [blame] | 309 | DCCP_SKB_CB(skb)->dccpd_seq = dreq->dreq_iss; |
Arnaldo Carvalho de Melo | 2d0817d | 2006-03-20 22:32:06 -0800 | [diff] [blame] | 310 | |
| 311 | if (dccp_insert_options(sk, skb)) { |
| 312 | kfree_skb(skb); |
| 313 | return NULL; |
| 314 | } |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 315 | |
Gerrit Renker | 09dbc38 | 2006-11-14 12:57:34 -0200 | [diff] [blame] | 316 | /* Build and checksum header */ |
Gerrit Renker | 9b42078 | 2006-11-10 11:22:32 -0200 | [diff] [blame] | 317 | dh = dccp_zeroed_hdr(skb, dccp_header_size); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 318 | |
| 319 | dh->dccph_sport = inet_sk(sk)->sport; |
| 320 | dh->dccph_dport = inet_rsk(req)->rmt_port; |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 321 | dh->dccph_doff = (dccp_header_size + |
| 322 | DCCP_SKB_CB(skb)->dccpd_opt_len) / 4; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 323 | dh->dccph_type = DCCP_PKT_RESPONSE; |
| 324 | dh->dccph_x = 1; |
Arnaldo Carvalho de Melo | 67e6b62 | 2005-09-16 16:58:40 -0700 | [diff] [blame] | 325 | dccp_hdr_set_seq(dh, dreq->dreq_iss); |
| 326 | dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), dreq->dreq_isr); |
| 327 | dccp_hdr_response(skb)->dccph_resp_service = dreq->dreq_service; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 328 | |
Gerrit Renker | 6f4e5ff | 2006-11-10 17:43:06 -0200 | [diff] [blame] | 329 | dccp_csum_outgoing(skb); |
| 330 | |
Gerrit Renker | e11d9d3 | 2006-11-13 13:12:07 -0200 | [diff] [blame] | 331 | /* We use `acked' to remember that a Response was already sent. */ |
| 332 | inet_rsk(req)->acked = 1; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 333 | DCCP_INC_STATS(DCCP_MIB_OUTSEGS); |
| 334 | return skb; |
| 335 | } |
| 336 | |
Arnaldo Carvalho de Melo | f21e68c | 2005-12-13 23:24:16 -0800 | [diff] [blame] | 337 | EXPORT_SYMBOL_GPL(dccp_make_response); |
| 338 | |
Arnaldo Carvalho de Melo | 017487d | 2006-03-20 19:25:24 -0800 | [diff] [blame] | 339 | static struct sk_buff *dccp_make_reset(struct sock *sk, struct dst_entry *dst, |
| 340 | const enum dccp_reset_codes code) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 341 | { |
| 342 | struct dccp_hdr *dh; |
| 343 | struct dccp_sock *dp = dccp_sk(sk); |
Arnaldo Carvalho de Melo | 118b2c9 | 2006-03-20 22:31:09 -0800 | [diff] [blame] | 344 | const u32 dccp_header_size = sizeof(struct dccp_hdr) + |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 345 | sizeof(struct dccp_hdr_ext) + |
| 346 | sizeof(struct dccp_hdr_reset); |
Arnaldo Carvalho de Melo | 118b2c9 | 2006-03-20 22:31:09 -0800 | [diff] [blame] | 347 | struct sk_buff *skb = sock_wmalloc(sk, sk->sk_prot->max_header, 1, |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 348 | GFP_ATOMIC); |
| 349 | if (skb == NULL) |
| 350 | return NULL; |
| 351 | |
| 352 | /* Reserve space for headers. */ |
Arnaldo Carvalho de Melo | 118b2c9 | 2006-03-20 22:31:09 -0800 | [diff] [blame] | 353 | skb_reserve(skb, sk->sk_prot->max_header); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 354 | |
| 355 | skb->dst = dst_clone(dst); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 356 | |
| 357 | dccp_inc_seqno(&dp->dccps_gss); |
| 358 | |
| 359 | DCCP_SKB_CB(skb)->dccpd_reset_code = code; |
| 360 | DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_RESET; |
| 361 | DCCP_SKB_CB(skb)->dccpd_seq = dp->dccps_gss; |
Arnaldo Carvalho de Melo | 2d0817d | 2006-03-20 22:32:06 -0800 | [diff] [blame] | 362 | |
| 363 | if (dccp_insert_options(sk, skb)) { |
| 364 | kfree_skb(skb); |
| 365 | return NULL; |
| 366 | } |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 367 | |
Gerrit Renker | 9b42078 | 2006-11-10 11:22:32 -0200 | [diff] [blame] | 368 | dh = dccp_zeroed_hdr(skb, dccp_header_size); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 369 | |
| 370 | dh->dccph_sport = inet_sk(sk)->sport; |
| 371 | dh->dccph_dport = inet_sk(sk)->dport; |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 372 | dh->dccph_doff = (dccp_header_size + |
| 373 | DCCP_SKB_CB(skb)->dccpd_opt_len) / 4; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 374 | dh->dccph_type = DCCP_PKT_RESET; |
| 375 | dh->dccph_x = 1; |
| 376 | dccp_hdr_set_seq(dh, dp->dccps_gss); |
| 377 | dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), dp->dccps_gsr); |
| 378 | |
| 379 | dccp_hdr_reset(skb)->dccph_reset_code = code; |
Gerrit Renker | 6f4e5ff | 2006-11-10 17:43:06 -0200 | [diff] [blame] | 380 | inet_csk(sk)->icsk_af_ops->send_check(sk, 0, skb); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 381 | |
| 382 | DCCP_INC_STATS(DCCP_MIB_OUTSEGS); |
| 383 | return skb; |
| 384 | } |
| 385 | |
Arnaldo Carvalho de Melo | 017487d | 2006-03-20 19:25:24 -0800 | [diff] [blame] | 386 | int dccp_send_reset(struct sock *sk, enum dccp_reset_codes code) |
| 387 | { |
| 388 | /* |
| 389 | * FIXME: what if rebuild_header fails? |
| 390 | * Should we be doing a rebuild_header here? |
| 391 | */ |
| 392 | int err = inet_sk_rebuild_header(sk); |
| 393 | |
| 394 | if (err == 0) { |
| 395 | struct sk_buff *skb = dccp_make_reset(sk, sk->sk_dst_cache, |
| 396 | code); |
| 397 | if (skb != NULL) { |
| 398 | memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); |
David S. Miller | e89862f | 2007-01-26 01:04:55 -0800 | [diff] [blame] | 399 | err = inet_csk(sk)->icsk_af_ops->queue_xmit(skb, 0); |
Gerrit Renker | b9df3cb | 2006-11-14 11:21:36 -0200 | [diff] [blame] | 400 | return net_xmit_eval(err); |
Arnaldo Carvalho de Melo | 017487d | 2006-03-20 19:25:24 -0800 | [diff] [blame] | 401 | } |
| 402 | } |
| 403 | |
| 404 | return err; |
| 405 | } |
| 406 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 407 | /* |
| 408 | * Do all connect socket setups that can be done AF independent. |
| 409 | */ |
| 410 | static inline void dccp_connect_init(struct sock *sk) |
| 411 | { |
Arnaldo Carvalho de Melo | f21e68c | 2005-12-13 23:24:16 -0800 | [diff] [blame] | 412 | struct dccp_sock *dp = dccp_sk(sk); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 413 | struct dst_entry *dst = __sk_dst_get(sk); |
| 414 | struct inet_connection_sock *icsk = inet_csk(sk); |
| 415 | |
| 416 | sk->sk_err = 0; |
| 417 | sock_reset_flag(sk, SOCK_DONE); |
| 418 | |
| 419 | dccp_sync_mss(sk, dst_mtu(dst)); |
| 420 | |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 421 | /* |
Arnaldo Carvalho de Melo | f21e68c | 2005-12-13 23:24:16 -0800 | [diff] [blame] | 422 | * SWL and AWL are initially adjusted so that they are not less than |
| 423 | * the initial Sequence Numbers received and sent, respectively: |
| 424 | * SWL := max(GSR + 1 - floor(W/4), ISR), |
| 425 | * AWL := max(GSS - W' + 1, ISS). |
| 426 | * These adjustments MUST be applied only at the beginning of the |
| 427 | * connection. |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 428 | */ |
Gerrit Renker | d7f7365 | 2006-11-13 13:34:38 -0200 | [diff] [blame] | 429 | dccp_update_gss(sk, dp->dccps_iss); |
Arnaldo Carvalho de Melo | f21e68c | 2005-12-13 23:24:16 -0800 | [diff] [blame] | 430 | dccp_set_seqno(&dp->dccps_awl, max48(dp->dccps_awl, dp->dccps_iss)); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 431 | |
Gerrit Renker | d7f7365 | 2006-11-13 13:34:38 -0200 | [diff] [blame] | 432 | /* S.GAR - greatest valid acknowledgement number received on a non-Sync; |
| 433 | * initialized to S.ISS (sec. 8.5) */ |
| 434 | dp->dccps_gar = dp->dccps_iss; |
| 435 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 436 | icsk->icsk_retransmits = 0; |
Ian McDonald | 97e5848 | 2006-08-26 19:16:45 -0700 | [diff] [blame] | 437 | init_timer(&dp->dccps_xmit_timer); |
| 438 | dp->dccps_xmit_timer.data = (unsigned long)sk; |
| 439 | dp->dccps_xmit_timer.function = dccp_write_xmit_timer; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 440 | } |
| 441 | |
| 442 | int dccp_connect(struct sock *sk) |
| 443 | { |
| 444 | struct sk_buff *skb; |
| 445 | struct inet_connection_sock *icsk = inet_csk(sk); |
| 446 | |
| 447 | dccp_connect_init(sk); |
| 448 | |
Arnaldo Carvalho de Melo | 118b2c9 | 2006-03-20 22:31:09 -0800 | [diff] [blame] | 449 | skb = alloc_skb(sk->sk_prot->max_header, sk->sk_allocation); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 450 | if (unlikely(skb == NULL)) |
| 451 | return -ENOBUFS; |
| 452 | |
| 453 | /* Reserve space for headers. */ |
Arnaldo Carvalho de Melo | 118b2c9 | 2006-03-20 22:31:09 -0800 | [diff] [blame] | 454 | skb_reserve(skb, sk->sk_prot->max_header); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 455 | |
| 456 | DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_REQUEST; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 457 | |
Herbert Xu | 48918a4 | 2005-10-30 11:20:59 +1100 | [diff] [blame] | 458 | dccp_skb_entail(sk, skb); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 459 | dccp_transmit_skb(sk, skb_clone(skb, GFP_KERNEL)); |
| 460 | DCCP_INC_STATS(DCCP_MIB_ACTIVEOPENS); |
| 461 | |
| 462 | /* Timer for repeating the REQUEST until an answer. */ |
Arnaldo Carvalho de Melo | 27258ee | 2005-08-09 20:30:56 -0700 | [diff] [blame] | 463 | inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, |
| 464 | icsk->icsk_rto, DCCP_RTO_MAX); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 465 | return 0; |
| 466 | } |
| 467 | |
Arnaldo Carvalho de Melo | f21e68c | 2005-12-13 23:24:16 -0800 | [diff] [blame] | 468 | EXPORT_SYMBOL_GPL(dccp_connect); |
| 469 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 470 | void dccp_send_ack(struct sock *sk) |
| 471 | { |
| 472 | /* If we have been reset, we may not send again. */ |
| 473 | if (sk->sk_state != DCCP_CLOSED) { |
Arnaldo Carvalho de Melo | 118b2c9 | 2006-03-20 22:31:09 -0800 | [diff] [blame] | 474 | struct sk_buff *skb = alloc_skb(sk->sk_prot->max_header, |
| 475 | GFP_ATOMIC); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 476 | |
| 477 | if (skb == NULL) { |
| 478 | inet_csk_schedule_ack(sk); |
| 479 | inet_csk(sk)->icsk_ack.ato = TCP_ATO_MIN; |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 480 | inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK, |
| 481 | TCP_DELACK_MAX, |
| 482 | DCCP_RTO_MAX); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 483 | return; |
| 484 | } |
| 485 | |
| 486 | /* Reserve space for headers */ |
Arnaldo Carvalho de Melo | 118b2c9 | 2006-03-20 22:31:09 -0800 | [diff] [blame] | 487 | skb_reserve(skb, sk->sk_prot->max_header); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 488 | DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_ACK; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 489 | dccp_transmit_skb(sk, skb); |
| 490 | } |
| 491 | } |
| 492 | |
| 493 | EXPORT_SYMBOL_GPL(dccp_send_ack); |
| 494 | |
| 495 | void dccp_send_delayed_ack(struct sock *sk) |
| 496 | { |
| 497 | struct inet_connection_sock *icsk = inet_csk(sk); |
| 498 | /* |
| 499 | * FIXME: tune this timer. elapsed time fixes the skew, so no problem |
| 500 | * with using 2s, and active senders also piggyback the ACK into a |
| 501 | * DATAACK packet, so this is really for quiescent senders. |
| 502 | */ |
| 503 | unsigned long timeout = jiffies + 2 * HZ; |
| 504 | |
| 505 | /* Use new timeout only if there wasn't a older one earlier. */ |
| 506 | if (icsk->icsk_ack.pending & ICSK_ACK_TIMER) { |
| 507 | /* If delack timer was blocked or is about to expire, |
| 508 | * send ACK now. |
| 509 | * |
| 510 | * FIXME: check the "about to expire" part |
| 511 | */ |
| 512 | if (icsk->icsk_ack.blocked) { |
| 513 | dccp_send_ack(sk); |
| 514 | return; |
| 515 | } |
| 516 | |
| 517 | if (!time_before(timeout, icsk->icsk_ack.timeout)) |
| 518 | timeout = icsk->icsk_ack.timeout; |
| 519 | } |
| 520 | icsk->icsk_ack.pending |= ICSK_ACK_SCHED | ICSK_ACK_TIMER; |
| 521 | icsk->icsk_ack.timeout = timeout; |
| 522 | sk_reset_timer(sk, &icsk->icsk_delack_timer, timeout); |
| 523 | } |
| 524 | |
Arnaldo Carvalho de Melo | e92ae93 | 2005-08-17 03:10:59 -0300 | [diff] [blame] | 525 | void dccp_send_sync(struct sock *sk, const u64 seq, |
| 526 | const enum dccp_pkt_type pkt_type) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 527 | { |
| 528 | /* |
| 529 | * We are not putting this on the write queue, so |
| 530 | * dccp_transmit_skb() will set the ownership to this |
| 531 | * sock. |
| 532 | */ |
Arnaldo Carvalho de Melo | 118b2c9 | 2006-03-20 22:31:09 -0800 | [diff] [blame] | 533 | struct sk_buff *skb = alloc_skb(sk->sk_prot->max_header, GFP_ATOMIC); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 534 | |
| 535 | if (skb == NULL) |
| 536 | /* FIXME: how to make sure the sync is sent? */ |
| 537 | return; |
| 538 | |
| 539 | /* Reserve space for headers and prepare control bits. */ |
Arnaldo Carvalho de Melo | 118b2c9 | 2006-03-20 22:31:09 -0800 | [diff] [blame] | 540 | skb_reserve(skb, sk->sk_prot->max_header); |
Arnaldo Carvalho de Melo | e92ae93 | 2005-08-17 03:10:59 -0300 | [diff] [blame] | 541 | DCCP_SKB_CB(skb)->dccpd_type = pkt_type; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 542 | DCCP_SKB_CB(skb)->dccpd_seq = seq; |
| 543 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 544 | dccp_transmit_skb(sk, skb); |
| 545 | } |
| 546 | |
Arnaldo Carvalho de Melo | b61fafc | 2006-03-20 21:25:11 -0800 | [diff] [blame] | 547 | EXPORT_SYMBOL_GPL(dccp_send_sync); |
| 548 | |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 549 | /* |
| 550 | * Send a DCCP_PKT_CLOSE/CLOSEREQ. The caller locks the socket for us. This |
| 551 | * cannot be allowed to fail queueing a DCCP_PKT_CLOSE/CLOSEREQ frame under |
| 552 | * any circumstances. |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 553 | */ |
Arnaldo Carvalho de Melo | 7ad07e7 | 2005-08-23 21:50:06 -0700 | [diff] [blame] | 554 | void dccp_send_close(struct sock *sk, const int active) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 555 | { |
| 556 | struct dccp_sock *dp = dccp_sk(sk); |
| 557 | struct sk_buff *skb; |
Al Viro | 7d877f3 | 2005-10-21 03:20:43 -0400 | [diff] [blame] | 558 | const gfp_t prio = active ? GFP_KERNEL : GFP_ATOMIC; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 559 | |
Arnaldo Carvalho de Melo | 7ad07e7 | 2005-08-23 21:50:06 -0700 | [diff] [blame] | 560 | skb = alloc_skb(sk->sk_prot->max_header, prio); |
| 561 | if (skb == NULL) |
| 562 | return; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 563 | |
| 564 | /* Reserve space for headers and prepare control bits. */ |
| 565 | skb_reserve(skb, sk->sk_prot->max_header); |
Arnaldo Carvalho de Melo | 7690af3 | 2005-08-13 20:34:54 -0300 | [diff] [blame] | 566 | DCCP_SKB_CB(skb)->dccpd_type = dp->dccps_role == DCCP_ROLE_CLIENT ? |
| 567 | DCCP_PKT_CLOSE : DCCP_PKT_CLOSEREQ; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 568 | |
Arnaldo Carvalho de Melo | 7ad07e7 | 2005-08-23 21:50:06 -0700 | [diff] [blame] | 569 | if (active) { |
Ian McDonald | 97e5848 | 2006-08-26 19:16:45 -0700 | [diff] [blame] | 570 | dccp_write_xmit(sk, 1); |
Herbert Xu | 48918a4 | 2005-10-30 11:20:59 +1100 | [diff] [blame] | 571 | dccp_skb_entail(sk, skb); |
Arnaldo Carvalho de Melo | 7ad07e7 | 2005-08-23 21:50:06 -0700 | [diff] [blame] | 572 | dccp_transmit_skb(sk, skb_clone(skb, prio)); |
Ian McDonald | 97e5848 | 2006-08-26 19:16:45 -0700 | [diff] [blame] | 573 | /* FIXME do we need a retransmit timer here? */ |
Arnaldo Carvalho de Melo | 7ad07e7 | 2005-08-23 21:50:06 -0700 | [diff] [blame] | 574 | } else |
| 575 | dccp_transmit_skb(sk, skb); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 576 | } |