17c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo/* 27c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * net/dccp/output.c 38109b02b5397ed52a32c116163a62a34f4768b26Arnaldo Carvalho de Melo * 47c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * An implementation of the DCCP protocol 57c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * Arnaldo Carvalho de Melo <acme@conectiva.com.br> 67c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * 77c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * This program is free software; you can redistribute it and/or 87c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * modify it under the terms of the GNU General Public License 97c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * as published by the Free Software Foundation; either version 107c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * 2 of the License, or (at your option) any later version. 117c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo */ 127c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 137c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo#include <linux/dccp.h> 1448918a4dbd6c599d6af30bd64cb355fadca708ebHerbert Xu#include <linux/kernel.h> 157c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo#include <linux/skbuff.h> 165a0e3ad6af8660be21ca98a971cd00f331318c05Tejun Heo#include <linux/slab.h> 177c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 1814c850212ed8f8cbb5972ad6b8812e08a0bc901cArnaldo Carvalho de Melo#include <net/inet_sock.h> 197c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo#include <net/sock.h> 207c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 21ae31c3399d17b1f7bc1742724f70476b5417744fArnaldo Carvalho de Melo#include "ackvec.h" 227c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo#include "ccid.h" 237c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo#include "dccp.h" 247c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 257c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melostatic inline void dccp_event_ack_sent(struct sock *sk) 267c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo{ 277c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo inet_csk_clear_xmit_timer(sk, ICSK_TIME_DACK); 287c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo} 297c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 308695e80193fed35f27c06f462bd5b76132fd5697Gerrit Renker/* enqueue @skb on sk_send_head for retransmission, return clone to send now */ 318695e80193fed35f27c06f462bd5b76132fd5697Gerrit Renkerstatic struct sk_buff *dccp_skb_entail(struct sock *sk, struct sk_buff *skb) 3248918a4dbd6c599d6af30bd64cb355fadca708ebHerbert Xu{ 3348918a4dbd6c599d6af30bd64cb355fadca708ebHerbert Xu skb_set_owner_w(skb, sk); 3448918a4dbd6c599d6af30bd64cb355fadca708ebHerbert Xu WARN_ON(sk->sk_send_head); 3548918a4dbd6c599d6af30bd64cb355fadca708ebHerbert Xu sk->sk_send_head = skb; 368695e80193fed35f27c06f462bd5b76132fd5697Gerrit Renker return skb_clone(sk->sk_send_head, gfp_any()); 3748918a4dbd6c599d6af30bd64cb355fadca708ebHerbert Xu} 3848918a4dbd6c599d6af30bd64cb355fadca708ebHerbert Xu 397c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo/* 407c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * All SKB's seen here are completely headerless. It is our 417c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * job to build the DCCP header, and pass the packet down to 427c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * IP so it can do the same plus pass the packet off to the 437c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * device. 447c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo */ 4548918a4dbd6c599d6af30bd64cb355fadca708ebHerbert Xustatic int dccp_transmit_skb(struct sock *sk, struct sk_buff *skb) 467c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo{ 477c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo if (likely(skb != NULL)) { 48d9d8da805dcb503ef8ee49918a94d49085060f23David S. Miller struct inet_sock *inet = inet_sk(sk); 4957cca05af1e20fdc65b55be52c042c234f86c866Arnaldo Carvalho de Melo const struct inet_connection_sock *icsk = inet_csk(sk); 507c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo struct dccp_sock *dp = dccp_sk(sk); 517c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb); 527c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo struct dccp_hdr *dh; 537c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* XXX For now we're using only 48 bits sequence numbers */ 54118b2c9532c853ebdf15c21128d30a343b89ea45Arnaldo Carvalho de Melo const u32 dccp_header_size = sizeof(*dh) + 557c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo sizeof(struct dccp_hdr_ext) + 567690af3fff7633e40b1b9950eb8489129251d074Arnaldo Carvalho de Melo dccp_packet_hdr_len(dcb->dccpd_type); 577c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo int err, set_ack = 1; 587c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo u64 ackno = dp->dccps_gsr; 5973f18fdbca3f92b90aeaee16f5175fe30496e218Gerrit Renker /* 6073f18fdbca3f92b90aeaee16f5175fe30496e218Gerrit Renker * Increment GSS here already in case the option code needs it. 6173f18fdbca3f92b90aeaee16f5175fe30496e218Gerrit Renker * Update GSS for real only if option processing below succeeds. 6273f18fdbca3f92b90aeaee16f5175fe30496e218Gerrit Renker */ 6373f18fdbca3f92b90aeaee16f5175fe30496e218Gerrit Renker dcb->dccpd_seq = ADD48(dp->dccps_gss, 1); 647c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 657c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo switch (dcb->dccpd_type) { 667c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo case DCCP_PKT_DATA: 677c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo set_ack = 0; 68edc9e81917157d1e73bf081d4fbcad7c34d32783Herbert Xu /* fall through */ 69edc9e81917157d1e73bf081d4fbcad7c34d32783Herbert Xu case DCCP_PKT_DATAACK: 70ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker case DCCP_PKT_RESET: 717c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo break; 72edc9e81917157d1e73bf081d4fbcad7c34d32783Herbert Xu 73afe00251dd9b53d51de91ff0099961f42bbf3754Andrea Bittau case DCCP_PKT_REQUEST: 74afe00251dd9b53d51de91ff0099961f42bbf3754Andrea Bittau set_ack = 0; 7573f18fdbca3f92b90aeaee16f5175fe30496e218Gerrit Renker /* Use ISS on the first (non-retransmitted) Request. */ 7673f18fdbca3f92b90aeaee16f5175fe30496e218Gerrit Renker if (icsk->icsk_retransmits == 0) 7773f18fdbca3f92b90aeaee16f5175fe30496e218Gerrit Renker dcb->dccpd_seq = dp->dccps_iss; 78afe00251dd9b53d51de91ff0099961f42bbf3754Andrea Bittau /* fall through */ 79afe00251dd9b53d51de91ff0099961f42bbf3754Andrea Bittau 807c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo case DCCP_PKT_SYNC: 817c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo case DCCP_PKT_SYNCACK: 82b0d045ca45a44d9f8bd66d0a10558b10c60f895aGerrit Renker ackno = dcb->dccpd_ack_seq; 83edc9e81917157d1e73bf081d4fbcad7c34d32783Herbert Xu /* fall through */ 84edc9e81917157d1e73bf081d4fbcad7c34d32783Herbert Xu default: 85edc9e81917157d1e73bf081d4fbcad7c34d32783Herbert Xu /* 86ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker * Set owner/destructor: some skbs are allocated via 87ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker * alloc_skb (e.g. when retransmission may happen). 88ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker * Only Data, DataAck, and Reset packets should come 89ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker * through here with skb->sk set. 90edc9e81917157d1e73bf081d4fbcad7c34d32783Herbert Xu */ 91edc9e81917157d1e73bf081d4fbcad7c34d32783Herbert Xu WARN_ON(skb->sk); 92edc9e81917157d1e73bf081d4fbcad7c34d32783Herbert Xu skb_set_owner_w(skb, sk); 937c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo break; 947c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo } 9524117727b753426d85ba09671c24854834f81b2cArnaldo Carvalho de Melo 962d0817d11eaec57435feb61493331a763f732a2bArnaldo Carvalho de Melo if (dccp_insert_options(sk, skb)) { 972d0817d11eaec57435feb61493331a763f732a2bArnaldo Carvalho de Melo kfree_skb(skb); 982d0817d11eaec57435feb61493331a763f732a2bArnaldo Carvalho de Melo return -EPROTO; 992d0817d11eaec57435feb61493331a763f732a2bArnaldo Carvalho de Melo } 100c9eaf17341834de00351bf79f16b2d879c8aea96YOSHIFUJI Hideaki 101fda0fd6c5b722cc48e904e0daafedca275d332afHerbert Xu 1027c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* Build DCCP header and checksum it. */ 1039b42078ed6edfe04e9dc9a59b946ad912aeef717Gerrit Renker dh = dccp_zeroed_hdr(skb, dccp_header_size); 1047c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo dh->dccph_type = dcb->dccpd_type; 105c720c7e8383aff1cb219bddf474ed89d850336e3Eric Dumazet dh->dccph_sport = inet->inet_sport; 106c720c7e8383aff1cb219bddf474ed89d850336e3Eric Dumazet dh->dccph_dport = inet->inet_dport; 1077c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo dh->dccph_doff = (dccp_header_size + dcb->dccpd_opt_len) / 4; 1087c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo dh->dccph_ccval = dcb->dccpd_ccval; 1096f4e5fff1e4d46714ea554fd83e44eab534e8b11Gerrit Renker dh->dccph_cscov = dp->dccps_pcslen; 1107c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* XXX For now we're using only 48 bits sequence numbers */ 1117c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo dh->dccph_x = 1; 1127c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 11373f18fdbca3f92b90aeaee16f5175fe30496e218Gerrit Renker dccp_update_gss(sk, dcb->dccpd_seq); 1147c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo dccp_hdr_set_seq(dh, dp->dccps_gss); 1157c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo if (set_ack) 1167c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), ackno); 1177c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 1187c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo switch (dcb->dccpd_type) { 1197c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo case DCCP_PKT_REQUEST: 1207690af3fff7633e40b1b9950eb8489129251d074Arnaldo Carvalho de Melo dccp_hdr_request(skb)->dccph_req_service = 12167e6b629212fa9ffb7420e8a88a41806af637e28Arnaldo Carvalho de Melo dp->dccps_service; 12273f18fdbca3f92b90aeaee16f5175fe30496e218Gerrit Renker /* 12373f18fdbca3f92b90aeaee16f5175fe30496e218Gerrit Renker * Limit Ack window to ISS <= P.ackno <= GSS, so that 12473f18fdbca3f92b90aeaee16f5175fe30496e218Gerrit Renker * only Responses to Requests we sent are considered. 12573f18fdbca3f92b90aeaee16f5175fe30496e218Gerrit Renker */ 12673f18fdbca3f92b90aeaee16f5175fe30496e218Gerrit Renker dp->dccps_awl = dp->dccps_iss; 1277c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo break; 1287c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo case DCCP_PKT_RESET: 1297690af3fff7633e40b1b9950eb8489129251d074Arnaldo Carvalho de Melo dccp_hdr_reset(skb)->dccph_reset_code = 1307690af3fff7633e40b1b9950eb8489129251d074Arnaldo Carvalho de Melo dcb->dccpd_reset_code; 1317c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo break; 1327c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo } 1337c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 134bb29624614c2afe2873ee8ee97cf09df42701694Herbert Xu icsk->icsk_af_ops->send_check(sk, skb); 1357c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 1367ad07e7cf343181002c10c39d3f57a88e4903d4fArnaldo Carvalho de Melo if (set_ack) 1377c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo dccp_event_ack_sent(sk); 1387c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 1397c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo DCCP_INC_STATS(DCCP_MIB_OUTSEGS); 1407c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 141b0270e91014dabfceaf37f5b40ad51bbf21a1302Eric Dumazet err = icsk->icsk_af_ops->queue_xmit(sk, skb, &inet->cork.fl); 142b9df3cb8cf9a96e63dfdcd3056a9cbc71f2459e7Gerrit Renker return net_xmit_eval(err); 1437c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo } 1447c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo return -ENOBUFS; 1457c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo} 1467c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 1476179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker/** 14825985edcedea6396277003854657b5f3cb31a628Lucas De Marchi * dccp_determine_ccmps - Find out about CCID-specific packet-size limits 1496179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker * We only consider the HC-sender CCID for setting the CCMPS (RFC 4340, 14.), 1506179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker * since the RX CCID is restricted to feedback packets (Acks), which are small 1516179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker * in comparison with the data traffic. A value of 0 means "no current CCMPS". 1526179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker */ 1536179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renkerstatic u32 dccp_determine_ccmps(const struct dccp_sock *dp) 1546179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker{ 1556179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker const struct ccid *tx_ccid = dp->dccps_hc_tx_ccid; 1566179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker 1576179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker if (tx_ccid == NULL || tx_ccid->ccid_ops == NULL) 1586179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker return 0; 1596179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker return tx_ccid->ccid_ops->ccid_ccmps; 1606179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker} 1616179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker 1627c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melounsigned int dccp_sync_mss(struct sock *sk, u32 pmtu) 1637c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo{ 164d83d8461f902c672bc1bd8fbc6a94e19f092da97Arnaldo Carvalho de Melo struct inet_connection_sock *icsk = inet_csk(sk); 1657c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo struct dccp_sock *dp = dccp_sk(sk); 1666179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker u32 ccmps = dccp_determine_ccmps(dp); 167361a5c1dd0bd7bb2b90e7fe9127b366d3566522eGerrit Renker u32 cur_mps = ccmps ? min(pmtu, ccmps) : pmtu; 1687c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 1696179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker /* Account for header lengths and IPv4/v6 option overhead */ 1706179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker cur_mps -= (icsk->icsk_af_ops->net_header_len + icsk->icsk_ext_hdr_len + 1716179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker sizeof(struct dccp_hdr) + sizeof(struct dccp_hdr_ext)); 1727c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 1737c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* 174361a5c1dd0bd7bb2b90e7fe9127b366d3566522eGerrit Renker * Leave enough headroom for common DCCP header options. 175361a5c1dd0bd7bb2b90e7fe9127b366d3566522eGerrit Renker * This only considers options which may appear on DCCP-Data packets, as 176361a5c1dd0bd7bb2b90e7fe9127b366d3566522eGerrit Renker * per table 3 in RFC 4340, 5.8. When running out of space for other 177361a5c1dd0bd7bb2b90e7fe9127b366d3566522eGerrit Renker * options (eg. Ack Vector which can take up to 255 bytes), it is better 178361a5c1dd0bd7bb2b90e7fe9127b366d3566522eGerrit Renker * to schedule a separate Ack. Thus we leave headroom for the following: 179361a5c1dd0bd7bb2b90e7fe9127b366d3566522eGerrit Renker * - 1 byte for Slow Receiver (11.6) 180361a5c1dd0bd7bb2b90e7fe9127b366d3566522eGerrit Renker * - 6 bytes for Timestamp (13.1) 181361a5c1dd0bd7bb2b90e7fe9127b366d3566522eGerrit Renker * - 10 bytes for Timestamp Echo (13.3) 182361a5c1dd0bd7bb2b90e7fe9127b366d3566522eGerrit Renker * - 8 bytes for NDP count (7.7, when activated) 183361a5c1dd0bd7bb2b90e7fe9127b366d3566522eGerrit Renker * - 6 bytes for Data Checksum (9.3) 184361a5c1dd0bd7bb2b90e7fe9127b366d3566522eGerrit Renker * - %DCCPAV_MIN_OPTLEN bytes for Ack Vector size (11.4, when enabled) 1857c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo */ 186361a5c1dd0bd7bb2b90e7fe9127b366d3566522eGerrit Renker cur_mps -= roundup(1 + 6 + 10 + dp->dccps_send_ndp_count * 8 + 6 + 187361a5c1dd0bd7bb2b90e7fe9127b366d3566522eGerrit Renker (dp->dccps_hc_rx_ackvec ? DCCPAV_MIN_OPTLEN : 0), 4); 1887c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 1897c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* And store cached results */ 190d83d8461f902c672bc1bd8fbc6a94e19f092da97Arnaldo Carvalho de Melo icsk->icsk_pmtu_cookie = pmtu; 1916179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker dp->dccps_mss_cache = cur_mps; 1927c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 1936179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker return cur_mps; 1947c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo} 1957c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 196f21e68caa0ddffddf98a1e729e734a470957b6ecArnaldo Carvalho de MeloEXPORT_SYMBOL_GPL(dccp_sync_mss); 197f21e68caa0ddffddf98a1e729e734a470957b6ecArnaldo Carvalho de Melo 198c530cfb1ce1e8f230744c3f3bd86771f50725053Arnaldo Carvalho de Melovoid dccp_write_space(struct sock *sk) 199c530cfb1ce1e8f230744c3f3bd86771f50725053Arnaldo Carvalho de Melo{ 20043815482370c510c569fd18edb57afcb0fa8cab6Eric Dumazet struct socket_wq *wq; 201c530cfb1ce1e8f230744c3f3bd86771f50725053Arnaldo Carvalho de Melo 20243815482370c510c569fd18edb57afcb0fa8cab6Eric Dumazet rcu_read_lock(); 20343815482370c510c569fd18edb57afcb0fa8cab6Eric Dumazet wq = rcu_dereference(sk->sk_wq); 20443815482370c510c569fd18edb57afcb0fa8cab6Eric Dumazet if (wq_has_sleeper(wq)) 20543815482370c510c569fd18edb57afcb0fa8cab6Eric Dumazet wake_up_interruptible(&wq->wait); 206c530cfb1ce1e8f230744c3f3bd86771f50725053Arnaldo Carvalho de Melo /* Should agree with poll, otherwise some programs break */ 207c530cfb1ce1e8f230744c3f3bd86771f50725053Arnaldo Carvalho de Melo if (sock_writeable(sk)) 2088d8ad9d7c4bfe79bc91b7fc419ecfb9dcdfe6a51Pavel Emelyanov sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); 209c530cfb1ce1e8f230744c3f3bd86771f50725053Arnaldo Carvalho de Melo 21043815482370c510c569fd18edb57afcb0fa8cab6Eric Dumazet rcu_read_unlock(); 211c530cfb1ce1e8f230744c3f3bd86771f50725053Arnaldo Carvalho de Melo} 212c530cfb1ce1e8f230744c3f3bd86771f50725053Arnaldo Carvalho de Melo 213d6809c12b3334a929c39bf08ea63bd819e0500f7Arnaldo Carvalho de Melo/** 214b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker * dccp_wait_for_ccid - Await CCID send permission 215bc8498721dfe3f7d537f4f75302be7dbe9c7b939Gerrit Renker * @sk: socket to wait for 216b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker * @delay: timeout in jiffies 2172c53040f018b6c36a46eec75b9b937aaa5f78e6dBen Hutchings * 218b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker * This is used by CCIDs which need to delay the send time in process context. 219d6809c12b3334a929c39bf08ea63bd819e0500f7Arnaldo Carvalho de Melo */ 220b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renkerstatic int dccp_wait_for_ccid(struct sock *sk, unsigned long delay) 221d6809c12b3334a929c39bf08ea63bd819e0500f7Arnaldo Carvalho de Melo{ 222d6809c12b3334a929c39bf08ea63bd819e0500f7Arnaldo Carvalho de Melo DEFINE_WAIT(wait); 223b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker long remaining; 224d6809c12b3334a929c39bf08ea63bd819e0500f7Arnaldo Carvalho de Melo 225b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 226b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker sk->sk_write_pending++; 227b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker release_sock(sk); 228bc8498721dfe3f7d537f4f75302be7dbe9c7b939Gerrit Renker 229b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker remaining = schedule_timeout(delay); 230d6809c12b3334a929c39bf08ea63bd819e0500f7Arnaldo Carvalho de Melo 231b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker lock_sock(sk); 232b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker sk->sk_write_pending--; 233aa395145165cb06a0d0885221bbe0ce4a564391dEric Dumazet finish_wait(sk_sleep(sk), &wait); 234b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker 235b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker if (signal_pending(current) || sk->sk_err) 236b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker return -1; 237b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker return remaining; 238d6809c12b3334a929c39bf08ea63bd819e0500f7Arnaldo Carvalho de Melo} 239d6809c12b3334a929c39bf08ea63bd819e0500f7Arnaldo Carvalho de Melo 240dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker/** 241dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker * dccp_xmit_packet - Send data packet under control of CCID 242dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker * Transmits next-queued payload and informs CCID to account for the packet. 243dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker */ 244dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renkerstatic void dccp_xmit_packet(struct sock *sk) 245dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker{ 246dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker int err, len; 247dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker struct dccp_sock *dp = dccp_sk(sk); 248871a2c16c21b988688b4ab1a78eadd969765c0a3Tomasz Grobelny struct sk_buff *skb = dccp_qpolicy_pop(sk); 249dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker 250dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker if (unlikely(skb == NULL)) 251dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker return; 252dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker len = skb->len; 253dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker 254dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker if (sk->sk_state == DCCP_PARTOPEN) { 255dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker const u32 cur_mps = dp->dccps_mss_cache - DCCP_FEATNEG_OVERHEAD; 256dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker /* 257dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker * See 8.1.5 - Handshake Completion. 258dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker * 259dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker * For robustness we resend Confirm options until the client has 260dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker * entered OPEN. During the initial feature negotiation, the MPS 261dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker * is smaller than usual, reduced by the Change/Confirm options. 262dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker */ 263dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker if (!list_empty(&dp->dccps_featneg) && len > cur_mps) { 264dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker DCCP_WARN("Payload too large (%d) for featneg.\n", len); 265dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker dccp_send_ack(sk); 266dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker dccp_feat_list_purge(&dp->dccps_featneg); 267dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker } 268dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker 269dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker inet_csk_schedule_ack(sk); 270dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK, 271dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker inet_csk(sk)->icsk_rto, 272dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker DCCP_RTO_MAX); 273dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_DATAACK; 274dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker } else if (dccp_ack_pending(sk)) { 275dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_DATAACK; 276dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker } else { 277dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_DATA; 278dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker } 279dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker 280dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker err = dccp_transmit_skb(sk, skb); 281dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker if (err) 282dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker dccp_pr_debug("transmit_skb() returned err=%d\n", err); 283dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker /* 284dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker * Register this one as sent even if an error occurred. To the remote 285dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker * end a local packet drop is indistinguishable from network loss, i.e. 286dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker * any local drop will eventually be reported via receiver feedback. 287dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker */ 288dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker ccid_hc_tx_packet_sent(dp->dccps_hc_tx_ccid, sk, len); 289d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker 290d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker /* 291d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker * If the CCID needs to transfer additional header options out-of-band 292d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker * (e.g. Ack Vectors or feature-negotiation options), it activates this 293d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker * flag to schedule a Sync. The Sync will automatically incorporate all 294d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker * currently pending header options, thus clearing the backlog. 295d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker */ 296d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker if (dp->dccps_sync_scheduled) 297d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker dccp_send_sync(sk, dp->dccps_gsr, DCCP_PKT_SYNC); 298dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker} 299dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker 300b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker/** 301b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker * dccp_flush_write_queue - Drain queue at end of connection 302b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker * Since dccp_sendmsg queues packets without waiting for them to be sent, it may 303b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker * happen that the TX queue is not empty at the end of a connection. We give the 304b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker * HC-sender CCID a grace period of up to @time_budget jiffies. If this function 305b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker * returns with a non-empty write queue, it will be purged later. 306b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker */ 307b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renkervoid dccp_flush_write_queue(struct sock *sk, long *time_budget) 308b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker{ 309b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker struct dccp_sock *dp = dccp_sk(sk); 310b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker struct sk_buff *skb; 311b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker long delay, rc; 312b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker 313b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker while (*time_budget > 0 && (skb = skb_peek(&sk->sk_write_queue))) { 314b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker rc = ccid_hc_tx_send_packet(dp->dccps_hc_tx_ccid, sk, skb); 315b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker 316b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker switch (ccid_packet_dequeue_eval(rc)) { 317b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker case CCID_PACKET_WILL_DEQUEUE_LATER: 318b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker /* 319b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker * If the CCID determines when to send, the next sending 320b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker * time is unknown or the CCID may not even send again 321b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker * (e.g. remote host crashes or lost Ack packets). 322b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker */ 323b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker DCCP_WARN("CCID did not manage to send all packets\n"); 324b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker return; 325b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker case CCID_PACKET_DELAY: 326b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker delay = msecs_to_jiffies(rc); 327b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker if (delay > *time_budget) 328b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker return; 329b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker rc = dccp_wait_for_ccid(sk, delay); 330b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker if (rc < 0) 331b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker return; 332b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker *time_budget -= (delay - rc); 333b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker /* check again if we can send now */ 334b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker break; 335b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker case CCID_PACKET_SEND_AT_ONCE: 336b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker dccp_xmit_packet(sk); 337b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker break; 338b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker case CCID_PACKET_ERR: 339b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker skb_dequeue(&sk->sk_write_queue); 340b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker kfree_skb(skb); 341b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker dccp_pr_debug("packet discarded due to err=%ld\n", rc); 342b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker } 343b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker } 344b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker} 345b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker 346b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renkervoid dccp_write_xmit(struct sock *sk) 34727258ee54f8cd4a43d09319aa5448145afc2cb8dArnaldo Carvalho de Melo{ 34897e5848dd39e7e76bd6077735ebb5473763ab9c5Ian McDonald struct dccp_sock *dp = dccp_sk(sk); 34997e5848dd39e7e76bd6077735ebb5473763ab9c5Ian McDonald struct sk_buff *skb; 35097e5848dd39e7e76bd6077735ebb5473763ab9c5Ian McDonald 351871a2c16c21b988688b4ab1a78eadd969765c0a3Tomasz Grobelny while ((skb = dccp_qpolicy_top(sk))) { 352dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker int rc = ccid_hc_tx_send_packet(dp->dccps_hc_tx_ccid, sk, skb); 353d6809c12b3334a929c39bf08ea63bd819e0500f7Arnaldo Carvalho de Melo 354dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker switch (ccid_packet_dequeue_eval(rc)) { 355dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker case CCID_PACKET_WILL_DEQUEUE_LATER: 356dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker return; 357dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker case CCID_PACKET_DELAY: 358b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker sk_reset_timer(sk, &dp->dccps_xmit_timer, 359b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker jiffies + msecs_to_jiffies(rc)); 360b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker return; 361dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker case CCID_PACKET_SEND_AT_ONCE: 362dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker dccp_xmit_packet(sk); 363dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker break; 364dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker case CCID_PACKET_ERR: 365871a2c16c21b988688b4ab1a78eadd969765c0a3Tomasz Grobelny dccp_qpolicy_drop(sk, skb); 366dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker dccp_pr_debug("packet discarded due to err=%d\n", rc); 367f6282f4da5eb67e08eff94d73a1911c3a008846aGerrit Renker } 36897e5848dd39e7e76bd6077735ebb5473763ab9c5Ian McDonald } 36927258ee54f8cd4a43d09319aa5448145afc2cb8dArnaldo Carvalho de Melo} 37027258ee54f8cd4a43d09319aa5448145afc2cb8dArnaldo Carvalho de Melo 37159435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker/** 37259435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker * dccp_retransmit_skb - Retransmit Request, Close, or CloseReq packets 37359435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker * There are only four retransmittable packet types in DCCP: 37459435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker * - Request in client-REQUEST state (sec. 8.1.1), 37559435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker * - CloseReq in server-CLOSEREQ state (sec. 8.3), 37659435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker * - Close in node-CLOSING state (sec. 8.3), 37759435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker * - Acks in client-PARTOPEN state (sec. 8.1.5, handled by dccp_delack_timer()). 37859435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker * This function expects sk->sk_send_head to contain the original skb. 37959435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker */ 38059435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renkerint dccp_retransmit_skb(struct sock *sk) 3817c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo{ 38259435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker WARN_ON(sk->sk_send_head == NULL); 38359435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker 38457cca05af1e20fdc65b55be52c042c234f86c866Arnaldo Carvalho de Melo if (inet_csk(sk)->icsk_af_ops->rebuild_header(sk) != 0) 3857c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo return -EHOSTUNREACH; /* Routing failure or similar. */ 3867c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 38759435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker /* this count is used to distinguish original and retransmitted skb */ 38859435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker inet_csk(sk)->icsk_retransmits++; 38959435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker 39059435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker return dccp_transmit_skb(sk, skb_clone(sk->sk_send_head, GFP_ATOMIC)); 3917c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo} 3927c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 3937c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melostruct sk_buff *dccp_make_response(struct sock *sk, struct dst_entry *dst, 3947c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo struct request_sock *req) 3957c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo{ 3967c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo struct dccp_hdr *dh; 39767e6b629212fa9ffb7420e8a88a41806af637e28Arnaldo Carvalho de Melo struct dccp_request_sock *dreq; 398118b2c9532c853ebdf15c21128d30a343b89ea45Arnaldo Carvalho de Melo const u32 dccp_header_size = sizeof(struct dccp_hdr) + 3997c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo sizeof(struct dccp_hdr_ext) + 4007c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo sizeof(struct dccp_hdr_response); 401118b2c9532c853ebdf15c21128d30a343b89ea45Arnaldo Carvalho de Melo struct sk_buff *skb = sock_wmalloc(sk, sk->sk_prot->max_header, 1, 4027c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo GFP_ATOMIC); 4037c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo if (skb == NULL) 4047c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo return NULL; 4057c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 4067c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* Reserve space for headers. */ 407118b2c9532c853ebdf15c21128d30a343b89ea45Arnaldo Carvalho de Melo skb_reserve(skb, sk->sk_prot->max_header); 4087c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 409adf30907d63893e4208dfe3f5c88ae12bc2f25d5Eric Dumazet skb_dst_set(skb, dst_clone(dst)); 4107c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 41167e6b629212fa9ffb7420e8a88a41806af637e28Arnaldo Carvalho de Melo dreq = dccp_rsk(req); 412f541fb7e20c848f947ca65fbf169efe69400c942Samuel Jero if (inet_rsk(req)->acked) /* increase GSS upon retransmission */ 413f541fb7e20c848f947ca65fbf169efe69400c942Samuel Jero dccp_inc_seqno(&dreq->dreq_gss); 4147c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_RESPONSE; 415f541fb7e20c848f947ca65fbf169efe69400c942Samuel Jero DCCP_SKB_CB(skb)->dccpd_seq = dreq->dreq_gss; 4162d0817d11eaec57435feb61493331a763f732a2bArnaldo Carvalho de Melo 4170c1168398ecbfacbb27203b281bde20ec9f78017Gerrit Renker /* Resolve feature dependencies resulting from choice of CCID */ 4180c1168398ecbfacbb27203b281bde20ec9f78017Gerrit Renker if (dccp_feat_server_ccid_dependencies(dreq)) 4190c1168398ecbfacbb27203b281bde20ec9f78017Gerrit Renker goto response_failed; 4200c1168398ecbfacbb27203b281bde20ec9f78017Gerrit Renker 4210c1168398ecbfacbb27203b281bde20ec9f78017Gerrit Renker if (dccp_insert_options_rsk(dreq, skb)) 4220c1168398ecbfacbb27203b281bde20ec9f78017Gerrit Renker goto response_failed; 4237c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 42409dbc3895e3242346bd434dae743c456fd28fc6aGerrit Renker /* Build and checksum header */ 4259b42078ed6edfe04e9dc9a59b946ad912aeef717Gerrit Renker dh = dccp_zeroed_hdr(skb, dccp_header_size); 4267c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 427b44084c2c822f99dd3f2334b288b7e463d222662Eric Dumazet dh->dccph_sport = htons(inet_rsk(req)->ir_num); 428634fb979e8f3a70f04c1f2f519d0cd1142eb5c1aEric Dumazet dh->dccph_dport = inet_rsk(req)->ir_rmt_port; 4297690af3fff7633e40b1b9950eb8489129251d074Arnaldo Carvalho de Melo dh->dccph_doff = (dccp_header_size + 4307690af3fff7633e40b1b9950eb8489129251d074Arnaldo Carvalho de Melo DCCP_SKB_CB(skb)->dccpd_opt_len) / 4; 4317c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo dh->dccph_type = DCCP_PKT_RESPONSE; 4327c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo dh->dccph_x = 1; 433f541fb7e20c848f947ca65fbf169efe69400c942Samuel Jero dccp_hdr_set_seq(dh, dreq->dreq_gss); 434f541fb7e20c848f947ca65fbf169efe69400c942Samuel Jero dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), dreq->dreq_gsr); 43567e6b629212fa9ffb7420e8a88a41806af637e28Arnaldo Carvalho de Melo dccp_hdr_response(skb)->dccph_resp_service = dreq->dreq_service; 4367c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 4376f4e5fff1e4d46714ea554fd83e44eab534e8b11Gerrit Renker dccp_csum_outgoing(skb); 4386f4e5fff1e4d46714ea554fd83e44eab534e8b11Gerrit Renker 439e11d9d30802278af22e78d8c10f348b683670cd9Gerrit Renker /* We use `acked' to remember that a Response was already sent. */ 440e11d9d30802278af22e78d8c10f348b683670cd9Gerrit Renker inet_rsk(req)->acked = 1; 4417c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo DCCP_INC_STATS(DCCP_MIB_OUTSEGS); 4427c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo return skb; 4430c1168398ecbfacbb27203b281bde20ec9f78017Gerrit Renkerresponse_failed: 4440c1168398ecbfacbb27203b281bde20ec9f78017Gerrit Renker kfree_skb(skb); 4450c1168398ecbfacbb27203b281bde20ec9f78017Gerrit Renker return NULL; 4467c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo} 4477c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 448f21e68caa0ddffddf98a1e729e734a470957b6ecArnaldo Carvalho de MeloEXPORT_SYMBOL_GPL(dccp_make_response); 449f21e68caa0ddffddf98a1e729e734a470957b6ecArnaldo Carvalho de Melo 450e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker/* answer offending packet in @rcv_skb with Reset from control socket @ctl */ 4517630f026810a63464e47391ab1e03674c33eb1b8Denis V. Lunevstruct sk_buff *dccp_ctl_make_reset(struct sock *sk, struct sk_buff *rcv_skb) 452e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker{ 453e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker struct dccp_hdr *rxdh = dccp_hdr(rcv_skb), *dh; 454e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker struct dccp_skb_cb *dcb = DCCP_SKB_CB(rcv_skb); 455e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker const u32 dccp_hdr_reset_len = sizeof(struct dccp_hdr) + 456e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker sizeof(struct dccp_hdr_ext) + 457e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker sizeof(struct dccp_hdr_reset); 458e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker struct dccp_hdr_reset *dhr; 459e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker struct sk_buff *skb; 460e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker 4617630f026810a63464e47391ab1e03674c33eb1b8Denis V. Lunev skb = alloc_skb(sk->sk_prot->max_header, GFP_ATOMIC); 462e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker if (skb == NULL) 463e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker return NULL; 464e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker 4657630f026810a63464e47391ab1e03674c33eb1b8Denis V. Lunev skb_reserve(skb, sk->sk_prot->max_header); 466e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker 467e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker /* Swap the send and the receive. */ 468e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker dh = dccp_zeroed_hdr(skb, dccp_hdr_reset_len); 469e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker dh->dccph_type = DCCP_PKT_RESET; 470e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker dh->dccph_sport = rxdh->dccph_dport; 471e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker dh->dccph_dport = rxdh->dccph_sport; 472e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker dh->dccph_doff = dccp_hdr_reset_len / 4; 473e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker dh->dccph_x = 1; 474e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker 475e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker dhr = dccp_hdr_reset(skb); 476e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker dhr->dccph_reset_code = dcb->dccpd_reset_code; 477e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker 478e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker switch (dcb->dccpd_reset_code) { 479e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker case DCCP_RESET_CODE_PACKET_ERROR: 480e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker dhr->dccph_reset_data[0] = rxdh->dccph_type; 481e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker break; 482e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker case DCCP_RESET_CODE_OPTION_ERROR: /* fall through */ 483e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker case DCCP_RESET_CODE_MANDATORY_ERROR: 484e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker memcpy(dhr->dccph_reset_data, dcb->dccpd_reset_data, 3); 485e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker break; 486e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker } 487e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker /* 488e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker * From RFC 4340, 8.3.1: 489e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker * If P.ackno exists, set R.seqno := P.ackno + 1. 490e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker * Else set R.seqno := 0. 491e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker */ 492e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker if (dcb->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ) 493e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker dccp_hdr_set_seq(dh, ADD48(dcb->dccpd_ack_seq, 1)); 494e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), dcb->dccpd_seq); 495e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker 496e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker dccp_csum_outgoing(skb); 497e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker return skb; 498e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker} 499e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker 500e356d37a096a990ea1a74c44c15640122e56110bGerrit RenkerEXPORT_SYMBOL_GPL(dccp_ctl_make_reset); 501e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker 502ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker/* send Reset on established socket, to close or abort the connection */ 503017487d7d1e905a5bb529f6a2bc8cf8ea14e2307Arnaldo Carvalho de Meloint dccp_send_reset(struct sock *sk, enum dccp_reset_codes code) 504017487d7d1e905a5bb529f6a2bc8cf8ea14e2307Arnaldo Carvalho de Melo{ 505ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker struct sk_buff *skb; 506017487d7d1e905a5bb529f6a2bc8cf8ea14e2307Arnaldo Carvalho de Melo /* 507017487d7d1e905a5bb529f6a2bc8cf8ea14e2307Arnaldo Carvalho de Melo * FIXME: what if rebuild_header fails? 508017487d7d1e905a5bb529f6a2bc8cf8ea14e2307Arnaldo Carvalho de Melo * Should we be doing a rebuild_header here? 509017487d7d1e905a5bb529f6a2bc8cf8ea14e2307Arnaldo Carvalho de Melo */ 510f53dc67c5e7babafe239b93a11678b0e05bead51Gerrit Renker int err = inet_csk(sk)->icsk_af_ops->rebuild_header(sk); 511017487d7d1e905a5bb529f6a2bc8cf8ea14e2307Arnaldo Carvalho de Melo 512ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker if (err != 0) 513ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker return err; 514ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker 515ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker skb = sock_wmalloc(sk, sk->sk_prot->max_header, 1, GFP_ATOMIC); 516ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker if (skb == NULL) 517ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker return -ENOBUFS; 518ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker 519ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker /* Reserve space for headers and prepare control bits. */ 520ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker skb_reserve(skb, sk->sk_prot->max_header); 521ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_RESET; 522ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker DCCP_SKB_CB(skb)->dccpd_reset_code = code; 523017487d7d1e905a5bb529f6a2bc8cf8ea14e2307Arnaldo Carvalho de Melo 524ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker return dccp_transmit_skb(sk, skb); 525017487d7d1e905a5bb529f6a2bc8cf8ea14e2307Arnaldo Carvalho de Melo} 526017487d7d1e905a5bb529f6a2bc8cf8ea14e2307Arnaldo Carvalho de Melo 5277c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo/* 5287c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * Do all connect socket setups that can be done AF independent. 5297c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo */ 53093344af44c0f649582bf1e3b5ecc45b3d19e98c2Gerrit Renkerint dccp_connect(struct sock *sk) 5317c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo{ 53293344af44c0f649582bf1e3b5ecc45b3d19e98c2Gerrit Renker struct sk_buff *skb; 533f21e68caa0ddffddf98a1e729e734a470957b6ecArnaldo Carvalho de Melo struct dccp_sock *dp = dccp_sk(sk); 5347c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo struct dst_entry *dst = __sk_dst_get(sk); 5357c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo struct inet_connection_sock *icsk = inet_csk(sk); 5367c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 5377c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo sk->sk_err = 0; 5387c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo sock_reset_flag(sk, SOCK_DONE); 539c9eaf17341834de00351bf79f16b2d879c8aea96YOSHIFUJI Hideaki 5407c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo dccp_sync_mss(sk, dst_mtu(dst)); 5417c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 5429eca0a47dee201a73967026985b5f0a79a46bd36Gerrit Renker /* do not connect if feature negotiation setup fails */ 5439eca0a47dee201a73967026985b5f0a79a46bd36Gerrit Renker if (dccp_feat_finalise_settings(dccp_sk(sk))) 5449eca0a47dee201a73967026985b5f0a79a46bd36Gerrit Renker return -EPROTO; 5459eca0a47dee201a73967026985b5f0a79a46bd36Gerrit Renker 54693344af44c0f649582bf1e3b5ecc45b3d19e98c2Gerrit Renker /* Initialise GAR as per 8.5; AWL/AWH are set in dccp_transmit_skb() */ 54793344af44c0f649582bf1e3b5ecc45b3d19e98c2Gerrit Renker dp->dccps_gar = dp->dccps_iss; 5487c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 549118b2c9532c853ebdf15c21128d30a343b89ea45Arnaldo Carvalho de Melo skb = alloc_skb(sk->sk_prot->max_header, sk->sk_allocation); 5507c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo if (unlikely(skb == NULL)) 5517c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo return -ENOBUFS; 5527c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 5537c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* Reserve space for headers. */ 554118b2c9532c853ebdf15c21128d30a343b89ea45Arnaldo Carvalho de Melo skb_reserve(skb, sk->sk_prot->max_header); 5557c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 5567c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_REQUEST; 5577c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 5588695e80193fed35f27c06f462bd5b76132fd5697Gerrit Renker dccp_transmit_skb(sk, dccp_skb_entail(sk, skb)); 5597c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo DCCP_INC_STATS(DCCP_MIB_ACTIVEOPENS); 5607c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 5617c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* Timer for repeating the REQUEST until an answer. */ 56293344af44c0f649582bf1e3b5ecc45b3d19e98c2Gerrit Renker icsk->icsk_retransmits = 0; 56327258ee54f8cd4a43d09319aa5448145afc2cb8dArnaldo Carvalho de Melo inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, 56427258ee54f8cd4a43d09319aa5448145afc2cb8dArnaldo Carvalho de Melo icsk->icsk_rto, DCCP_RTO_MAX); 5657c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo return 0; 5667c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo} 5677c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 568f21e68caa0ddffddf98a1e729e734a470957b6ecArnaldo Carvalho de MeloEXPORT_SYMBOL_GPL(dccp_connect); 569f21e68caa0ddffddf98a1e729e734a470957b6ecArnaldo Carvalho de Melo 5707c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melovoid dccp_send_ack(struct sock *sk) 5717c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo{ 5727c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* If we have been reset, we may not send again. */ 5737c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo if (sk->sk_state != DCCP_CLOSED) { 574118b2c9532c853ebdf15c21128d30a343b89ea45Arnaldo Carvalho de Melo struct sk_buff *skb = alloc_skb(sk->sk_prot->max_header, 575118b2c9532c853ebdf15c21128d30a343b89ea45Arnaldo Carvalho de Melo GFP_ATOMIC); 5767c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 5777c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo if (skb == NULL) { 5787c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo inet_csk_schedule_ack(sk); 5797c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo inet_csk(sk)->icsk_ack.ato = TCP_ATO_MIN; 5807690af3fff7633e40b1b9950eb8489129251d074Arnaldo Carvalho de Melo inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK, 5817690af3fff7633e40b1b9950eb8489129251d074Arnaldo Carvalho de Melo TCP_DELACK_MAX, 5827690af3fff7633e40b1b9950eb8489129251d074Arnaldo Carvalho de Melo DCCP_RTO_MAX); 5837c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo return; 5847c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo } 5857c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 5867c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* Reserve space for headers */ 587118b2c9532c853ebdf15c21128d30a343b89ea45Arnaldo Carvalho de Melo skb_reserve(skb, sk->sk_prot->max_header); 5887c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_ACK; 5897c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo dccp_transmit_skb(sk, skb); 5907c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo } 5917c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo} 5927c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 5937c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de MeloEXPORT_SYMBOL_GPL(dccp_send_ack); 5947c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 5951e2f0e5e8376f2a0ada8760fc9d3104e1a81382bGerrit Renker#if 0 596727ecc5faaf6e976fc841649821c865ebd1e822dGerrit Renker/* FIXME: Is this still necessary (11.3) - currently nowhere used by DCCP. */ 5977c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melovoid dccp_send_delayed_ack(struct sock *sk) 5987c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo{ 5997c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo struct inet_connection_sock *icsk = inet_csk(sk); 6007c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* 6017c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * FIXME: tune this timer. elapsed time fixes the skew, so no problem 6027c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * with using 2s, and active senders also piggyback the ACK into a 6037c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * DATAACK packet, so this is really for quiescent senders. 6047c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo */ 6057c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo unsigned long timeout = jiffies + 2 * HZ; 6067c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 6077c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* Use new timeout only if there wasn't a older one earlier. */ 6087c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo if (icsk->icsk_ack.pending & ICSK_ACK_TIMER) { 6097c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* If delack timer was blocked or is about to expire, 6107c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * send ACK now. 6117c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * 6127c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * FIXME: check the "about to expire" part 6137c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo */ 6147c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo if (icsk->icsk_ack.blocked) { 6157c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo dccp_send_ack(sk); 6167c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo return; 6177c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo } 6187c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 6197c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo if (!time_before(timeout, icsk->icsk_ack.timeout)) 6207c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo timeout = icsk->icsk_ack.timeout; 6217c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo } 6227c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo icsk->icsk_ack.pending |= ICSK_ACK_SCHED | ICSK_ACK_TIMER; 6237c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo icsk->icsk_ack.timeout = timeout; 6247c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo sk_reset_timer(sk, &icsk->icsk_delack_timer, timeout); 6257c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo} 6261e2f0e5e8376f2a0ada8760fc9d3104e1a81382bGerrit Renker#endif 6277c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 628b0d045ca45a44d9f8bd66d0a10558b10c60f895aGerrit Renkervoid dccp_send_sync(struct sock *sk, const u64 ackno, 629e92ae93a8aa66aea12935420cb22d4df1c18d023Arnaldo Carvalho de Melo const enum dccp_pkt_type pkt_type) 6307c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo{ 6317c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* 6327c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * We are not putting this on the write queue, so 6337c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * dccp_transmit_skb() will set the ownership to this 6347c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * sock. 6357c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo */ 636118b2c9532c853ebdf15c21128d30a343b89ea45Arnaldo Carvalho de Melo struct sk_buff *skb = alloc_skb(sk->sk_prot->max_header, GFP_ATOMIC); 6377c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 638b0d045ca45a44d9f8bd66d0a10558b10c60f895aGerrit Renker if (skb == NULL) { 6397c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* FIXME: how to make sure the sync is sent? */ 640b0d045ca45a44d9f8bd66d0a10558b10c60f895aGerrit Renker DCCP_CRIT("could not send %s", dccp_packet_name(pkt_type)); 6417c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo return; 642b0d045ca45a44d9f8bd66d0a10558b10c60f895aGerrit Renker } 6437c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 6447c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* Reserve space for headers and prepare control bits. */ 645118b2c9532c853ebdf15c21128d30a343b89ea45Arnaldo Carvalho de Melo skb_reserve(skb, sk->sk_prot->max_header); 646e92ae93a8aa66aea12935420cb22d4df1c18d023Arnaldo Carvalho de Melo DCCP_SKB_CB(skb)->dccpd_type = pkt_type; 647b0d045ca45a44d9f8bd66d0a10558b10c60f895aGerrit Renker DCCP_SKB_CB(skb)->dccpd_ack_seq = ackno; 6487c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 649d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker /* 650d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker * Clear the flag in case the Sync was scheduled for out-of-band data, 651d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker * such as carrying a long Ack Vector. 652d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker */ 653d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker dccp_sk(sk)->dccps_sync_scheduled = 0; 654d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker 6557c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo dccp_transmit_skb(sk, skb); 6567c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo} 6577c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 658b61fafc4ef3faf54236d57e3b230ca19167663bfArnaldo Carvalho de MeloEXPORT_SYMBOL_GPL(dccp_send_sync); 659b61fafc4ef3faf54236d57e3b230ca19167663bfArnaldo Carvalho de Melo 6607690af3fff7633e40b1b9950eb8489129251d074Arnaldo Carvalho de Melo/* 6617690af3fff7633e40b1b9950eb8489129251d074Arnaldo Carvalho de Melo * Send a DCCP_PKT_CLOSE/CLOSEREQ. The caller locks the socket for us. This 6627690af3fff7633e40b1b9950eb8489129251d074Arnaldo Carvalho de Melo * cannot be allowed to fail queueing a DCCP_PKT_CLOSE/CLOSEREQ frame under 6637690af3fff7633e40b1b9950eb8489129251d074Arnaldo Carvalho de Melo * any circumstances. 6647c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo */ 6657ad07e7cf343181002c10c39d3f57a88e4903d4fArnaldo Carvalho de Melovoid dccp_send_close(struct sock *sk, const int active) 6667c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo{ 6677c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo struct dccp_sock *dp = dccp_sk(sk); 6687c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo struct sk_buff *skb; 6697d877f3bda870ab5f001bd92528654471d5966b3Al Viro const gfp_t prio = active ? GFP_KERNEL : GFP_ATOMIC; 6707c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 6717ad07e7cf343181002c10c39d3f57a88e4903d4fArnaldo Carvalho de Melo skb = alloc_skb(sk->sk_prot->max_header, prio); 6727ad07e7cf343181002c10c39d3f57a88e4903d4fArnaldo Carvalho de Melo if (skb == NULL) 6737ad07e7cf343181002c10c39d3f57a88e4903d4fArnaldo Carvalho de Melo return; 6747c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 6757c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* Reserve space for headers and prepare control bits. */ 6767c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo skb_reserve(skb, sk->sk_prot->max_header); 677b8599d20708fa3bde1e414689f3474560c2d990bGerrit Renker if (dp->dccps_role == DCCP_ROLE_SERVER && !dp->dccps_server_timewait) 678b8599d20708fa3bde1e414689f3474560c2d990bGerrit Renker DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_CLOSEREQ; 679b8599d20708fa3bde1e414689f3474560c2d990bGerrit Renker else 680b8599d20708fa3bde1e414689f3474560c2d990bGerrit Renker DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_CLOSE; 6817c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 6827ad07e7cf343181002c10c39d3f57a88e4903d4fArnaldo Carvalho de Melo if (active) { 6838695e80193fed35f27c06f462bd5b76132fd5697Gerrit Renker skb = dccp_skb_entail(sk, skb); 68492d31920b84f258badf206eea8aaf5ac677ac535Gerrit Renker /* 68592d31920b84f258badf206eea8aaf5ac677ac535Gerrit Renker * Retransmission timer for active-close: RFC 4340, 8.3 requires 68692d31920b84f258badf206eea8aaf5ac677ac535Gerrit Renker * to retransmit the Close/CloseReq until the CLOSING/CLOSEREQ 68792d31920b84f258badf206eea8aaf5ac677ac535Gerrit Renker * state can be left. The initial timeout is 2 RTTs. 68892d31920b84f258badf206eea8aaf5ac677ac535Gerrit Renker * Since RTT measurement is done by the CCIDs, there is no easy 68992d31920b84f258badf206eea8aaf5ac677ac535Gerrit Renker * way to get an RTT sample. The fallback RTT from RFC 4340, 3.4 69092d31920b84f258badf206eea8aaf5ac677ac535Gerrit Renker * is too low (200ms); we use a high value to avoid unnecessary 69192d31920b84f258badf206eea8aaf5ac677ac535Gerrit Renker * retransmissions when the link RTT is > 0.2 seconds. 69292d31920b84f258badf206eea8aaf5ac677ac535Gerrit Renker * FIXME: Let main module sample RTTs and use that instead. 69392d31920b84f258badf206eea8aaf5ac677ac535Gerrit Renker */ 69492d31920b84f258badf206eea8aaf5ac677ac535Gerrit Renker inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, 69592d31920b84f258badf206eea8aaf5ac677ac535Gerrit Renker DCCP_TIMEOUT_INIT, DCCP_RTO_MAX); 6968695e80193fed35f27c06f462bd5b76132fd5697Gerrit Renker } 6978695e80193fed35f27c06f462bd5b76132fd5697Gerrit Renker dccp_transmit_skb(sk, skb); 6987c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo} 699