output.c revision 871a2c16c21b988688b4ab1a78eadd969765c0a3
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 30c25a18ba347f091d1ce620ba33e6772b60a528e1Arnaldo Carvalho de Melostatic void dccp_skb_entail(struct sock *sk, struct sk_buff *skb) 3148918a4dbd6c599d6af30bd64cb355fadca708ebHerbert Xu{ 3248918a4dbd6c599d6af30bd64cb355fadca708ebHerbert Xu skb_set_owner_w(skb, sk); 3348918a4dbd6c599d6af30bd64cb355fadca708ebHerbert Xu WARN_ON(sk->sk_send_head); 3448918a4dbd6c599d6af30bd64cb355fadca708ebHerbert Xu sk->sk_send_head = skb; 3548918a4dbd6c599d6af30bd64cb355fadca708ebHerbert Xu} 3648918a4dbd6c599d6af30bd64cb355fadca708ebHerbert Xu 377c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo/* 387c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * All SKB's seen here are completely headerless. It is our 397c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * job to build the DCCP header, and pass the packet down to 407c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * IP so it can do the same plus pass the packet off to the 417c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * device. 427c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo */ 4348918a4dbd6c599d6af30bd64cb355fadca708ebHerbert Xustatic int dccp_transmit_skb(struct sock *sk, struct sk_buff *skb) 447c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo{ 457c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo if (likely(skb != NULL)) { 467c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo const struct inet_sock *inet = inet_sk(sk); 4757cca05af1e20fdc65b55be52c042c234f86c866Arnaldo Carvalho de Melo const struct inet_connection_sock *icsk = inet_csk(sk); 487c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo struct dccp_sock *dp = dccp_sk(sk); 497c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb); 507c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo struct dccp_hdr *dh; 517c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* XXX For now we're using only 48 bits sequence numbers */ 52118b2c9532c853ebdf15c21128d30a343b89ea45Arnaldo Carvalho de Melo const u32 dccp_header_size = sizeof(*dh) + 537c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo sizeof(struct dccp_hdr_ext) + 547690af3fff7633e40b1b9950eb8489129251d074Arnaldo Carvalho de Melo dccp_packet_hdr_len(dcb->dccpd_type); 557c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo int err, set_ack = 1; 567c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo u64 ackno = dp->dccps_gsr; 5773f18fdbca3f92b90aeaee16f5175fe30496e218Gerrit Renker /* 5873f18fdbca3f92b90aeaee16f5175fe30496e218Gerrit Renker * Increment GSS here already in case the option code needs it. 5973f18fdbca3f92b90aeaee16f5175fe30496e218Gerrit Renker * Update GSS for real only if option processing below succeeds. 6073f18fdbca3f92b90aeaee16f5175fe30496e218Gerrit Renker */ 6173f18fdbca3f92b90aeaee16f5175fe30496e218Gerrit Renker dcb->dccpd_seq = ADD48(dp->dccps_gss, 1); 627c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 637c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo switch (dcb->dccpd_type) { 647c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo case DCCP_PKT_DATA: 657c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo set_ack = 0; 66edc9e81917157d1e73bf081d4fbcad7c34d32783Herbert Xu /* fall through */ 67edc9e81917157d1e73bf081d4fbcad7c34d32783Herbert Xu case DCCP_PKT_DATAACK: 68ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker case DCCP_PKT_RESET: 697c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo break; 70edc9e81917157d1e73bf081d4fbcad7c34d32783Herbert Xu 71afe00251dd9b53d51de91ff0099961f42bbf3754Andrea Bittau case DCCP_PKT_REQUEST: 72afe00251dd9b53d51de91ff0099961f42bbf3754Andrea Bittau set_ack = 0; 7373f18fdbca3f92b90aeaee16f5175fe30496e218Gerrit Renker /* Use ISS on the first (non-retransmitted) Request. */ 7473f18fdbca3f92b90aeaee16f5175fe30496e218Gerrit Renker if (icsk->icsk_retransmits == 0) 7573f18fdbca3f92b90aeaee16f5175fe30496e218Gerrit Renker dcb->dccpd_seq = dp->dccps_iss; 76afe00251dd9b53d51de91ff0099961f42bbf3754Andrea Bittau /* fall through */ 77afe00251dd9b53d51de91ff0099961f42bbf3754Andrea Bittau 787c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo case DCCP_PKT_SYNC: 797c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo case DCCP_PKT_SYNCACK: 80b0d045ca45a44d9f8bd66d0a10558b10c60f895aGerrit Renker ackno = dcb->dccpd_ack_seq; 81edc9e81917157d1e73bf081d4fbcad7c34d32783Herbert Xu /* fall through */ 82edc9e81917157d1e73bf081d4fbcad7c34d32783Herbert Xu default: 83edc9e81917157d1e73bf081d4fbcad7c34d32783Herbert Xu /* 84ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker * Set owner/destructor: some skbs are allocated via 85ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker * alloc_skb (e.g. when retransmission may happen). 86ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker * Only Data, DataAck, and Reset packets should come 87ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker * through here with skb->sk set. 88edc9e81917157d1e73bf081d4fbcad7c34d32783Herbert Xu */ 89edc9e81917157d1e73bf081d4fbcad7c34d32783Herbert Xu WARN_ON(skb->sk); 90edc9e81917157d1e73bf081d4fbcad7c34d32783Herbert Xu skb_set_owner_w(skb, sk); 917c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo break; 927c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo } 9324117727b753426d85ba09671c24854834f81b2cArnaldo Carvalho de Melo 942d0817d11eaec57435feb61493331a763f732a2bArnaldo Carvalho de Melo if (dccp_insert_options(sk, skb)) { 952d0817d11eaec57435feb61493331a763f732a2bArnaldo Carvalho de Melo kfree_skb(skb); 962d0817d11eaec57435feb61493331a763f732a2bArnaldo Carvalho de Melo return -EPROTO; 972d0817d11eaec57435feb61493331a763f732a2bArnaldo Carvalho de Melo } 98c9eaf17341834de00351bf79f16b2d879c8aea96YOSHIFUJI Hideaki 99fda0fd6c5b722cc48e904e0daafedca275d332afHerbert Xu 1007c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* Build DCCP header and checksum it. */ 1019b42078ed6edfe04e9dc9a59b946ad912aeef717Gerrit Renker dh = dccp_zeroed_hdr(skb, dccp_header_size); 1027c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo dh->dccph_type = dcb->dccpd_type; 103c720c7e8383aff1cb219bddf474ed89d850336e3Eric Dumazet dh->dccph_sport = inet->inet_sport; 104c720c7e8383aff1cb219bddf474ed89d850336e3Eric Dumazet dh->dccph_dport = inet->inet_dport; 1057c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo dh->dccph_doff = (dccp_header_size + dcb->dccpd_opt_len) / 4; 1067c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo dh->dccph_ccval = dcb->dccpd_ccval; 1076f4e5fff1e4d46714ea554fd83e44eab534e8b11Gerrit Renker dh->dccph_cscov = dp->dccps_pcslen; 1087c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* XXX For now we're using only 48 bits sequence numbers */ 1097c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo dh->dccph_x = 1; 1107c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 11173f18fdbca3f92b90aeaee16f5175fe30496e218Gerrit Renker dccp_update_gss(sk, dcb->dccpd_seq); 1127c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo dccp_hdr_set_seq(dh, dp->dccps_gss); 1137c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo if (set_ack) 1147c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), ackno); 1157c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 1167c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo switch (dcb->dccpd_type) { 1177c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo case DCCP_PKT_REQUEST: 1187690af3fff7633e40b1b9950eb8489129251d074Arnaldo Carvalho de Melo dccp_hdr_request(skb)->dccph_req_service = 11967e6b629212fa9ffb7420e8a88a41806af637e28Arnaldo Carvalho de Melo dp->dccps_service; 12073f18fdbca3f92b90aeaee16f5175fe30496e218Gerrit Renker /* 12173f18fdbca3f92b90aeaee16f5175fe30496e218Gerrit Renker * Limit Ack window to ISS <= P.ackno <= GSS, so that 12273f18fdbca3f92b90aeaee16f5175fe30496e218Gerrit Renker * only Responses to Requests we sent are considered. 12373f18fdbca3f92b90aeaee16f5175fe30496e218Gerrit Renker */ 12473f18fdbca3f92b90aeaee16f5175fe30496e218Gerrit Renker dp->dccps_awl = dp->dccps_iss; 1257c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo break; 1267c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo case DCCP_PKT_RESET: 1277690af3fff7633e40b1b9950eb8489129251d074Arnaldo Carvalho de Melo dccp_hdr_reset(skb)->dccph_reset_code = 1287690af3fff7633e40b1b9950eb8489129251d074Arnaldo Carvalho de Melo dcb->dccpd_reset_code; 1297c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo break; 1307c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo } 1317c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 132bb29624614c2afe2873ee8ee97cf09df42701694Herbert Xu icsk->icsk_af_ops->send_check(sk, skb); 1337c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 1347ad07e7cf343181002c10c39d3f57a88e4903d4fArnaldo Carvalho de Melo if (set_ack) 1357c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo dccp_event_ack_sent(sk); 1367c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 1377c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo DCCP_INC_STATS(DCCP_MIB_OUTSEGS); 1387c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 1394e15ed4d930297c127d280ca1d0c785be870def4Shan Wei err = icsk->icsk_af_ops->queue_xmit(skb); 140b9df3cb8cf9a96e63dfdcd3056a9cbc71f2459e7Gerrit Renker return net_xmit_eval(err); 1417c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo } 1427c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo return -ENOBUFS; 1437c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo} 1447c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 1456179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker/** 1466179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker * dccp_determine_ccmps - Find out about CCID-specfic packet-size limits 1476179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker * We only consider the HC-sender CCID for setting the CCMPS (RFC 4340, 14.), 1486179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker * since the RX CCID is restricted to feedback packets (Acks), which are small 1496179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker * in comparison with the data traffic. A value of 0 means "no current CCMPS". 1506179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker */ 1516179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renkerstatic u32 dccp_determine_ccmps(const struct dccp_sock *dp) 1526179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker{ 1536179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker const struct ccid *tx_ccid = dp->dccps_hc_tx_ccid; 1546179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker 1556179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker if (tx_ccid == NULL || tx_ccid->ccid_ops == NULL) 1566179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker return 0; 1576179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker return tx_ccid->ccid_ops->ccid_ccmps; 1586179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker} 1596179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker 1607c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melounsigned int dccp_sync_mss(struct sock *sk, u32 pmtu) 1617c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo{ 162d83d8461f902c672bc1bd8fbc6a94e19f092da97Arnaldo Carvalho de Melo struct inet_connection_sock *icsk = inet_csk(sk); 1637c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo struct dccp_sock *dp = dccp_sk(sk); 1646179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker u32 ccmps = dccp_determine_ccmps(dp); 165361a5c1dd0bd7bb2b90e7fe9127b366d3566522eGerrit Renker u32 cur_mps = ccmps ? min(pmtu, ccmps) : pmtu; 1667c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 1676179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker /* Account for header lengths and IPv4/v6 option overhead */ 1686179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker cur_mps -= (icsk->icsk_af_ops->net_header_len + icsk->icsk_ext_hdr_len + 1696179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker sizeof(struct dccp_hdr) + sizeof(struct dccp_hdr_ext)); 1707c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 1717c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* 172361a5c1dd0bd7bb2b90e7fe9127b366d3566522eGerrit Renker * Leave enough headroom for common DCCP header options. 173361a5c1dd0bd7bb2b90e7fe9127b366d3566522eGerrit Renker * This only considers options which may appear on DCCP-Data packets, as 174361a5c1dd0bd7bb2b90e7fe9127b366d3566522eGerrit Renker * per table 3 in RFC 4340, 5.8. When running out of space for other 175361a5c1dd0bd7bb2b90e7fe9127b366d3566522eGerrit Renker * options (eg. Ack Vector which can take up to 255 bytes), it is better 176361a5c1dd0bd7bb2b90e7fe9127b366d3566522eGerrit Renker * to schedule a separate Ack. Thus we leave headroom for the following: 177361a5c1dd0bd7bb2b90e7fe9127b366d3566522eGerrit Renker * - 1 byte for Slow Receiver (11.6) 178361a5c1dd0bd7bb2b90e7fe9127b366d3566522eGerrit Renker * - 6 bytes for Timestamp (13.1) 179361a5c1dd0bd7bb2b90e7fe9127b366d3566522eGerrit Renker * - 10 bytes for Timestamp Echo (13.3) 180361a5c1dd0bd7bb2b90e7fe9127b366d3566522eGerrit Renker * - 8 bytes for NDP count (7.7, when activated) 181361a5c1dd0bd7bb2b90e7fe9127b366d3566522eGerrit Renker * - 6 bytes for Data Checksum (9.3) 182361a5c1dd0bd7bb2b90e7fe9127b366d3566522eGerrit Renker * - %DCCPAV_MIN_OPTLEN bytes for Ack Vector size (11.4, when enabled) 1837c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo */ 184361a5c1dd0bd7bb2b90e7fe9127b366d3566522eGerrit Renker cur_mps -= roundup(1 + 6 + 10 + dp->dccps_send_ndp_count * 8 + 6 + 185361a5c1dd0bd7bb2b90e7fe9127b366d3566522eGerrit Renker (dp->dccps_hc_rx_ackvec ? DCCPAV_MIN_OPTLEN : 0), 4); 1867c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 1877c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* And store cached results */ 188d83d8461f902c672bc1bd8fbc6a94e19f092da97Arnaldo Carvalho de Melo icsk->icsk_pmtu_cookie = pmtu; 1896179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker dp->dccps_mss_cache = cur_mps; 1907c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 1916179983ad30c43313e153b35af52bd9ebd7745c3Gerrit Renker return cur_mps; 1927c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo} 1937c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 194f21e68caa0ddffddf98a1e729e734a470957b6ecArnaldo Carvalho de MeloEXPORT_SYMBOL_GPL(dccp_sync_mss); 195f21e68caa0ddffddf98a1e729e734a470957b6ecArnaldo Carvalho de Melo 196c530cfb1ce1e8f230744c3f3bd86771f50725053Arnaldo Carvalho de Melovoid dccp_write_space(struct sock *sk) 197c530cfb1ce1e8f230744c3f3bd86771f50725053Arnaldo Carvalho de Melo{ 19843815482370c510c569fd18edb57afcb0fa8cab6Eric Dumazet struct socket_wq *wq; 199c530cfb1ce1e8f230744c3f3bd86771f50725053Arnaldo Carvalho de Melo 20043815482370c510c569fd18edb57afcb0fa8cab6Eric Dumazet rcu_read_lock(); 20143815482370c510c569fd18edb57afcb0fa8cab6Eric Dumazet wq = rcu_dereference(sk->sk_wq); 20243815482370c510c569fd18edb57afcb0fa8cab6Eric Dumazet if (wq_has_sleeper(wq)) 20343815482370c510c569fd18edb57afcb0fa8cab6Eric Dumazet wake_up_interruptible(&wq->wait); 204c530cfb1ce1e8f230744c3f3bd86771f50725053Arnaldo Carvalho de Melo /* Should agree with poll, otherwise some programs break */ 205c530cfb1ce1e8f230744c3f3bd86771f50725053Arnaldo Carvalho de Melo if (sock_writeable(sk)) 2068d8ad9d7c4bfe79bc91b7fc419ecfb9dcdfe6a51Pavel Emelyanov sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); 207c530cfb1ce1e8f230744c3f3bd86771f50725053Arnaldo Carvalho de Melo 20843815482370c510c569fd18edb57afcb0fa8cab6Eric Dumazet rcu_read_unlock(); 209c530cfb1ce1e8f230744c3f3bd86771f50725053Arnaldo Carvalho de Melo} 210c530cfb1ce1e8f230744c3f3bd86771f50725053Arnaldo Carvalho de Melo 211d6809c12b3334a929c39bf08ea63bd819e0500f7Arnaldo Carvalho de Melo/** 212b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker * dccp_wait_for_ccid - Await CCID send permission 213bc8498721dfe3f7d537f4f75302be7dbe9c7b939Gerrit Renker * @sk: socket to wait for 214b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker * @delay: timeout in jiffies 215b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker * This is used by CCIDs which need to delay the send time in process context. 216d6809c12b3334a929c39bf08ea63bd819e0500f7Arnaldo Carvalho de Melo */ 217b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renkerstatic int dccp_wait_for_ccid(struct sock *sk, unsigned long delay) 218d6809c12b3334a929c39bf08ea63bd819e0500f7Arnaldo Carvalho de Melo{ 219d6809c12b3334a929c39bf08ea63bd819e0500f7Arnaldo Carvalho de Melo DEFINE_WAIT(wait); 220b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker long remaining; 221d6809c12b3334a929c39bf08ea63bd819e0500f7Arnaldo Carvalho de Melo 222b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 223b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker sk->sk_write_pending++; 224b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker release_sock(sk); 225bc8498721dfe3f7d537f4f75302be7dbe9c7b939Gerrit Renker 226b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker remaining = schedule_timeout(delay); 227d6809c12b3334a929c39bf08ea63bd819e0500f7Arnaldo Carvalho de Melo 228b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker lock_sock(sk); 229b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker sk->sk_write_pending--; 230aa395145165cb06a0d0885221bbe0ce4a564391dEric Dumazet finish_wait(sk_sleep(sk), &wait); 231b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker 232b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker if (signal_pending(current) || sk->sk_err) 233b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker return -1; 234b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker return remaining; 235d6809c12b3334a929c39bf08ea63bd819e0500f7Arnaldo Carvalho de Melo} 236d6809c12b3334a929c39bf08ea63bd819e0500f7Arnaldo Carvalho de Melo 237dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker/** 238dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker * dccp_xmit_packet - Send data packet under control of CCID 239dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker * Transmits next-queued payload and informs CCID to account for the packet. 240dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker */ 241dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renkerstatic void dccp_xmit_packet(struct sock *sk) 242dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker{ 243dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker int err, len; 244dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker struct dccp_sock *dp = dccp_sk(sk); 245871a2c16c21b988688b4ab1a78eadd969765c0a3Tomasz Grobelny struct sk_buff *skb = dccp_qpolicy_pop(sk); 246dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker 247dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker if (unlikely(skb == NULL)) 248dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker return; 249dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker len = skb->len; 250dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker 251dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker if (sk->sk_state == DCCP_PARTOPEN) { 252dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker const u32 cur_mps = dp->dccps_mss_cache - DCCP_FEATNEG_OVERHEAD; 253dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker /* 254dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker * See 8.1.5 - Handshake Completion. 255dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker * 256dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker * For robustness we resend Confirm options until the client has 257dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker * entered OPEN. During the initial feature negotiation, the MPS 258dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker * is smaller than usual, reduced by the Change/Confirm options. 259dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker */ 260dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker if (!list_empty(&dp->dccps_featneg) && len > cur_mps) { 261dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker DCCP_WARN("Payload too large (%d) for featneg.\n", len); 262dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker dccp_send_ack(sk); 263dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker dccp_feat_list_purge(&dp->dccps_featneg); 264dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker } 265dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker 266dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker inet_csk_schedule_ack(sk); 267dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK, 268dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker inet_csk(sk)->icsk_rto, 269dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker DCCP_RTO_MAX); 270dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_DATAACK; 271dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker } else if (dccp_ack_pending(sk)) { 272dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_DATAACK; 273dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker } else { 274dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_DATA; 275dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker } 276dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker 277dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker err = dccp_transmit_skb(sk, skb); 278dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker if (err) 279dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker dccp_pr_debug("transmit_skb() returned err=%d\n", err); 280dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker /* 281dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker * Register this one as sent even if an error occurred. To the remote 282dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker * end a local packet drop is indistinguishable from network loss, i.e. 283dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker * any local drop will eventually be reported via receiver feedback. 284dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker */ 285dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker ccid_hc_tx_packet_sent(dp->dccps_hc_tx_ccid, sk, len); 286d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker 287d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker /* 288d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker * If the CCID needs to transfer additional header options out-of-band 289d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker * (e.g. Ack Vectors or feature-negotiation options), it activates this 290d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker * flag to schedule a Sync. The Sync will automatically incorporate all 291d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker * currently pending header options, thus clearing the backlog. 292d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker */ 293d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker if (dp->dccps_sync_scheduled) 294d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker dccp_send_sync(sk, dp->dccps_gsr, DCCP_PKT_SYNC); 295dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker} 296dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker 297b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker/** 298b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker * dccp_flush_write_queue - Drain queue at end of connection 299b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker * Since dccp_sendmsg queues packets without waiting for them to be sent, it may 300b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker * happen that the TX queue is not empty at the end of a connection. We give the 301b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker * HC-sender CCID a grace period of up to @time_budget jiffies. If this function 302b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker * returns with a non-empty write queue, it will be purged later. 303b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker */ 304b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renkervoid dccp_flush_write_queue(struct sock *sk, long *time_budget) 305b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker{ 306b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker struct dccp_sock *dp = dccp_sk(sk); 307b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker struct sk_buff *skb; 308b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker long delay, rc; 309b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker 310b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker while (*time_budget > 0 && (skb = skb_peek(&sk->sk_write_queue))) { 311b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker rc = ccid_hc_tx_send_packet(dp->dccps_hc_tx_ccid, sk, skb); 312b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker 313b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker switch (ccid_packet_dequeue_eval(rc)) { 314b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker case CCID_PACKET_WILL_DEQUEUE_LATER: 315b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker /* 316b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker * If the CCID determines when to send, the next sending 317b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker * time is unknown or the CCID may not even send again 318b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker * (e.g. remote host crashes or lost Ack packets). 319b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker */ 320b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker DCCP_WARN("CCID did not manage to send all packets\n"); 321b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker return; 322b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker case CCID_PACKET_DELAY: 323b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker delay = msecs_to_jiffies(rc); 324b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker if (delay > *time_budget) 325b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker return; 326b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker rc = dccp_wait_for_ccid(sk, delay); 327b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker if (rc < 0) 328b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker return; 329b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker *time_budget -= (delay - rc); 330b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker /* check again if we can send now */ 331b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker break; 332b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker case CCID_PACKET_SEND_AT_ONCE: 333b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker dccp_xmit_packet(sk); 334b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker break; 335b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker case CCID_PACKET_ERR: 336b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker skb_dequeue(&sk->sk_write_queue); 337b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker kfree_skb(skb); 338b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker dccp_pr_debug("packet discarded due to err=%ld\n", rc); 339b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker } 340b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker } 341b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker} 342b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker 343b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renkervoid dccp_write_xmit(struct sock *sk) 34427258ee54f8cd4a43d09319aa5448145afc2cb8dArnaldo Carvalho de Melo{ 34597e5848dd39e7e76bd6077735ebb5473763ab9c5Ian McDonald struct dccp_sock *dp = dccp_sk(sk); 34697e5848dd39e7e76bd6077735ebb5473763ab9c5Ian McDonald struct sk_buff *skb; 34797e5848dd39e7e76bd6077735ebb5473763ab9c5Ian McDonald 348871a2c16c21b988688b4ab1a78eadd969765c0a3Tomasz Grobelny while ((skb = dccp_qpolicy_top(sk))) { 349dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker int rc = ccid_hc_tx_send_packet(dp->dccps_hc_tx_ccid, sk, skb); 350d6809c12b3334a929c39bf08ea63bd819e0500f7Arnaldo Carvalho de Melo 351dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker switch (ccid_packet_dequeue_eval(rc)) { 352dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker case CCID_PACKET_WILL_DEQUEUE_LATER: 353dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker return; 354dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker case CCID_PACKET_DELAY: 355b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker sk_reset_timer(sk, &dp->dccps_xmit_timer, 356b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker jiffies + msecs_to_jiffies(rc)); 357b1fcf55eea541af9efa5d39f5a0d1aec8ceca55dGerrit Renker return; 358dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker case CCID_PACKET_SEND_AT_ONCE: 359dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker dccp_xmit_packet(sk); 360dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker break; 361dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker case CCID_PACKET_ERR: 362871a2c16c21b988688b4ab1a78eadd969765c0a3Tomasz Grobelny dccp_qpolicy_drop(sk, skb); 363dc841e30eaea9f9f83c9ab1ee0b3ef9e5c95ce8aGerrit Renker dccp_pr_debug("packet discarded due to err=%d\n", rc); 364f6282f4da5eb67e08eff94d73a1911c3a008846aGerrit Renker } 36597e5848dd39e7e76bd6077735ebb5473763ab9c5Ian McDonald } 36627258ee54f8cd4a43d09319aa5448145afc2cb8dArnaldo Carvalho de Melo} 36727258ee54f8cd4a43d09319aa5448145afc2cb8dArnaldo Carvalho de Melo 36859435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker/** 36959435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker * dccp_retransmit_skb - Retransmit Request, Close, or CloseReq packets 37059435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker * There are only four retransmittable packet types in DCCP: 37159435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker * - Request in client-REQUEST state (sec. 8.1.1), 37259435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker * - CloseReq in server-CLOSEREQ state (sec. 8.3), 37359435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker * - Close in node-CLOSING state (sec. 8.3), 37459435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker * - Acks in client-PARTOPEN state (sec. 8.1.5, handled by dccp_delack_timer()). 37559435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker * This function expects sk->sk_send_head to contain the original skb. 37659435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker */ 37759435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renkerint dccp_retransmit_skb(struct sock *sk) 3787c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo{ 37959435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker WARN_ON(sk->sk_send_head == NULL); 38059435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker 38157cca05af1e20fdc65b55be52c042c234f86c866Arnaldo Carvalho de Melo if (inet_csk(sk)->icsk_af_ops->rebuild_header(sk) != 0) 3827c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo return -EHOSTUNREACH; /* Routing failure or similar. */ 3837c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 38459435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker /* this count is used to distinguish original and retransmitted skb */ 38559435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker inet_csk(sk)->icsk_retransmits++; 38659435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker 38759435444a13ed52d3444c5df26b73d3086bcd57bGerrit Renker return dccp_transmit_skb(sk, skb_clone(sk->sk_send_head, GFP_ATOMIC)); 3887c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo} 3897c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 3907c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melostruct sk_buff *dccp_make_response(struct sock *sk, struct dst_entry *dst, 3917c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo struct request_sock *req) 3927c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo{ 3937c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo struct dccp_hdr *dh; 39467e6b629212fa9ffb7420e8a88a41806af637e28Arnaldo Carvalho de Melo struct dccp_request_sock *dreq; 395118b2c9532c853ebdf15c21128d30a343b89ea45Arnaldo Carvalho de Melo const u32 dccp_header_size = sizeof(struct dccp_hdr) + 3967c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo sizeof(struct dccp_hdr_ext) + 3977c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo sizeof(struct dccp_hdr_response); 398118b2c9532c853ebdf15c21128d30a343b89ea45Arnaldo Carvalho de Melo struct sk_buff *skb = sock_wmalloc(sk, sk->sk_prot->max_header, 1, 3997c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo GFP_ATOMIC); 4007c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo if (skb == NULL) 4017c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo return NULL; 4027c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 4037c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* Reserve space for headers. */ 404118b2c9532c853ebdf15c21128d30a343b89ea45Arnaldo Carvalho de Melo skb_reserve(skb, sk->sk_prot->max_header); 4057c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 406adf30907d63893e4208dfe3f5c88ae12bc2f25d5Eric Dumazet skb_dst_set(skb, dst_clone(dst)); 4077c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 40867e6b629212fa9ffb7420e8a88a41806af637e28Arnaldo Carvalho de Melo dreq = dccp_rsk(req); 409e11d9d30802278af22e78d8c10f348b683670cd9Gerrit Renker if (inet_rsk(req)->acked) /* increase ISS upon retransmission */ 410e11d9d30802278af22e78d8c10f348b683670cd9Gerrit Renker dccp_inc_seqno(&dreq->dreq_iss); 4117c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_RESPONSE; 41267e6b629212fa9ffb7420e8a88a41806af637e28Arnaldo Carvalho de Melo DCCP_SKB_CB(skb)->dccpd_seq = dreq->dreq_iss; 4132d0817d11eaec57435feb61493331a763f732a2bArnaldo Carvalho de Melo 4140c1168398ecbfacbb27203b281bde20ec9f78017Gerrit Renker /* Resolve feature dependencies resulting from choice of CCID */ 4150c1168398ecbfacbb27203b281bde20ec9f78017Gerrit Renker if (dccp_feat_server_ccid_dependencies(dreq)) 4160c1168398ecbfacbb27203b281bde20ec9f78017Gerrit Renker goto response_failed; 4170c1168398ecbfacbb27203b281bde20ec9f78017Gerrit Renker 4180c1168398ecbfacbb27203b281bde20ec9f78017Gerrit Renker if (dccp_insert_options_rsk(dreq, skb)) 4190c1168398ecbfacbb27203b281bde20ec9f78017Gerrit Renker goto response_failed; 4207c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 42109dbc3895e3242346bd434dae743c456fd28fc6aGerrit Renker /* Build and checksum header */ 4229b42078ed6edfe04e9dc9a59b946ad912aeef717Gerrit Renker dh = dccp_zeroed_hdr(skb, dccp_header_size); 4237c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 424944f750227fa0beb2b440709687415621e2533a4Gerrit Renker dh->dccph_sport = inet_rsk(req)->loc_port; 4257c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo dh->dccph_dport = inet_rsk(req)->rmt_port; 4267690af3fff7633e40b1b9950eb8489129251d074Arnaldo Carvalho de Melo dh->dccph_doff = (dccp_header_size + 4277690af3fff7633e40b1b9950eb8489129251d074Arnaldo Carvalho de Melo DCCP_SKB_CB(skb)->dccpd_opt_len) / 4; 4287c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo dh->dccph_type = DCCP_PKT_RESPONSE; 4297c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo dh->dccph_x = 1; 43067e6b629212fa9ffb7420e8a88a41806af637e28Arnaldo Carvalho de Melo dccp_hdr_set_seq(dh, dreq->dreq_iss); 43167e6b629212fa9ffb7420e8a88a41806af637e28Arnaldo Carvalho de Melo dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), dreq->dreq_isr); 43267e6b629212fa9ffb7420e8a88a41806af637e28Arnaldo Carvalho de Melo dccp_hdr_response(skb)->dccph_resp_service = dreq->dreq_service; 4337c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 4346f4e5fff1e4d46714ea554fd83e44eab534e8b11Gerrit Renker dccp_csum_outgoing(skb); 4356f4e5fff1e4d46714ea554fd83e44eab534e8b11Gerrit Renker 436e11d9d30802278af22e78d8c10f348b683670cd9Gerrit Renker /* We use `acked' to remember that a Response was already sent. */ 437e11d9d30802278af22e78d8c10f348b683670cd9Gerrit Renker inet_rsk(req)->acked = 1; 4387c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo DCCP_INC_STATS(DCCP_MIB_OUTSEGS); 4397c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo return skb; 4400c1168398ecbfacbb27203b281bde20ec9f78017Gerrit Renkerresponse_failed: 4410c1168398ecbfacbb27203b281bde20ec9f78017Gerrit Renker kfree_skb(skb); 4420c1168398ecbfacbb27203b281bde20ec9f78017Gerrit Renker return NULL; 4437c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo} 4447c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 445f21e68caa0ddffddf98a1e729e734a470957b6ecArnaldo Carvalho de MeloEXPORT_SYMBOL_GPL(dccp_make_response); 446f21e68caa0ddffddf98a1e729e734a470957b6ecArnaldo Carvalho de Melo 447e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker/* answer offending packet in @rcv_skb with Reset from control socket @ctl */ 4487630f026810a63464e47391ab1e03674c33eb1b8Denis V. Lunevstruct sk_buff *dccp_ctl_make_reset(struct sock *sk, struct sk_buff *rcv_skb) 449e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker{ 450e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker struct dccp_hdr *rxdh = dccp_hdr(rcv_skb), *dh; 451e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker struct dccp_skb_cb *dcb = DCCP_SKB_CB(rcv_skb); 452e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker const u32 dccp_hdr_reset_len = sizeof(struct dccp_hdr) + 453e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker sizeof(struct dccp_hdr_ext) + 454e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker sizeof(struct dccp_hdr_reset); 455e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker struct dccp_hdr_reset *dhr; 456e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker struct sk_buff *skb; 457e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker 4587630f026810a63464e47391ab1e03674c33eb1b8Denis V. Lunev skb = alloc_skb(sk->sk_prot->max_header, GFP_ATOMIC); 459e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker if (skb == NULL) 460e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker return NULL; 461e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker 4627630f026810a63464e47391ab1e03674c33eb1b8Denis V. Lunev skb_reserve(skb, sk->sk_prot->max_header); 463e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker 464e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker /* Swap the send and the receive. */ 465e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker dh = dccp_zeroed_hdr(skb, dccp_hdr_reset_len); 466e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker dh->dccph_type = DCCP_PKT_RESET; 467e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker dh->dccph_sport = rxdh->dccph_dport; 468e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker dh->dccph_dport = rxdh->dccph_sport; 469e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker dh->dccph_doff = dccp_hdr_reset_len / 4; 470e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker dh->dccph_x = 1; 471e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker 472e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker dhr = dccp_hdr_reset(skb); 473e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker dhr->dccph_reset_code = dcb->dccpd_reset_code; 474e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker 475e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker switch (dcb->dccpd_reset_code) { 476e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker case DCCP_RESET_CODE_PACKET_ERROR: 477e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker dhr->dccph_reset_data[0] = rxdh->dccph_type; 478e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker break; 479e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker case DCCP_RESET_CODE_OPTION_ERROR: /* fall through */ 480e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker case DCCP_RESET_CODE_MANDATORY_ERROR: 481e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker memcpy(dhr->dccph_reset_data, dcb->dccpd_reset_data, 3); 482e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker break; 483e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker } 484e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker /* 485e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker * From RFC 4340, 8.3.1: 486e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker * If P.ackno exists, set R.seqno := P.ackno + 1. 487e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker * Else set R.seqno := 0. 488e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker */ 489e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker if (dcb->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ) 490e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker dccp_hdr_set_seq(dh, ADD48(dcb->dccpd_ack_seq, 1)); 491e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), dcb->dccpd_seq); 492e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker 493e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker dccp_csum_outgoing(skb); 494e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker return skb; 495e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker} 496e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker 497e356d37a096a990ea1a74c44c15640122e56110bGerrit RenkerEXPORT_SYMBOL_GPL(dccp_ctl_make_reset); 498e356d37a096a990ea1a74c44c15640122e56110bGerrit Renker 499ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker/* send Reset on established socket, to close or abort the connection */ 500017487d7d1e905a5bb529f6a2bc8cf8ea14e2307Arnaldo Carvalho de Meloint dccp_send_reset(struct sock *sk, enum dccp_reset_codes code) 501017487d7d1e905a5bb529f6a2bc8cf8ea14e2307Arnaldo Carvalho de Melo{ 502ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker struct sk_buff *skb; 503017487d7d1e905a5bb529f6a2bc8cf8ea14e2307Arnaldo Carvalho de Melo /* 504017487d7d1e905a5bb529f6a2bc8cf8ea14e2307Arnaldo Carvalho de Melo * FIXME: what if rebuild_header fails? 505017487d7d1e905a5bb529f6a2bc8cf8ea14e2307Arnaldo Carvalho de Melo * Should we be doing a rebuild_header here? 506017487d7d1e905a5bb529f6a2bc8cf8ea14e2307Arnaldo Carvalho de Melo */ 507f53dc67c5e7babafe239b93a11678b0e05bead51Gerrit Renker int err = inet_csk(sk)->icsk_af_ops->rebuild_header(sk); 508017487d7d1e905a5bb529f6a2bc8cf8ea14e2307Arnaldo Carvalho de Melo 509ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker if (err != 0) 510ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker return err; 511ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker 512ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker skb = sock_wmalloc(sk, sk->sk_prot->max_header, 1, GFP_ATOMIC); 513ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker if (skb == NULL) 514ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker return -ENOBUFS; 515ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker 516ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker /* Reserve space for headers and prepare control bits. */ 517ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker skb_reserve(skb, sk->sk_prot->max_header); 518ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_RESET; 519ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker DCCP_SKB_CB(skb)->dccpd_reset_code = code; 520017487d7d1e905a5bb529f6a2bc8cf8ea14e2307Arnaldo Carvalho de Melo 521ee1a15922d356aff0e31bf9bb9088ab346b8033aGerrit Renker return dccp_transmit_skb(sk, skb); 522017487d7d1e905a5bb529f6a2bc8cf8ea14e2307Arnaldo Carvalho de Melo} 523017487d7d1e905a5bb529f6a2bc8cf8ea14e2307Arnaldo Carvalho de Melo 5247c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo/* 5257c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * Do all connect socket setups that can be done AF independent. 5267c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo */ 52793344af44c0f649582bf1e3b5ecc45b3d19e98c2Gerrit Renkerint dccp_connect(struct sock *sk) 5287c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo{ 52993344af44c0f649582bf1e3b5ecc45b3d19e98c2Gerrit Renker struct sk_buff *skb; 530f21e68caa0ddffddf98a1e729e734a470957b6ecArnaldo Carvalho de Melo struct dccp_sock *dp = dccp_sk(sk); 5317c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo struct dst_entry *dst = __sk_dst_get(sk); 5327c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo struct inet_connection_sock *icsk = inet_csk(sk); 5337c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 5347c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo sk->sk_err = 0; 5357c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo sock_reset_flag(sk, SOCK_DONE); 536c9eaf17341834de00351bf79f16b2d879c8aea96YOSHIFUJI Hideaki 5377c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo dccp_sync_mss(sk, dst_mtu(dst)); 5387c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 5399eca0a47dee201a73967026985b5f0a79a46bd36Gerrit Renker /* do not connect if feature negotiation setup fails */ 5409eca0a47dee201a73967026985b5f0a79a46bd36Gerrit Renker if (dccp_feat_finalise_settings(dccp_sk(sk))) 5419eca0a47dee201a73967026985b5f0a79a46bd36Gerrit Renker return -EPROTO; 5429eca0a47dee201a73967026985b5f0a79a46bd36Gerrit Renker 54393344af44c0f649582bf1e3b5ecc45b3d19e98c2Gerrit Renker /* Initialise GAR as per 8.5; AWL/AWH are set in dccp_transmit_skb() */ 54493344af44c0f649582bf1e3b5ecc45b3d19e98c2Gerrit Renker dp->dccps_gar = dp->dccps_iss; 5457c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 546118b2c9532c853ebdf15c21128d30a343b89ea45Arnaldo Carvalho de Melo skb = alloc_skb(sk->sk_prot->max_header, sk->sk_allocation); 5477c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo if (unlikely(skb == NULL)) 5487c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo return -ENOBUFS; 5497c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 5507c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* Reserve space for headers. */ 551118b2c9532c853ebdf15c21128d30a343b89ea45Arnaldo Carvalho de Melo skb_reserve(skb, sk->sk_prot->max_header); 5527c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 5537c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_REQUEST; 5547c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 55548918a4dbd6c599d6af30bd64cb355fadca708ebHerbert Xu dccp_skb_entail(sk, skb); 5567c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo dccp_transmit_skb(sk, skb_clone(skb, GFP_KERNEL)); 5577c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo DCCP_INC_STATS(DCCP_MIB_ACTIVEOPENS); 5587c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 5597c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* Timer for repeating the REQUEST until an answer. */ 56093344af44c0f649582bf1e3b5ecc45b3d19e98c2Gerrit Renker icsk->icsk_retransmits = 0; 56127258ee54f8cd4a43d09319aa5448145afc2cb8dArnaldo Carvalho de Melo inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, 56227258ee54f8cd4a43d09319aa5448145afc2cb8dArnaldo Carvalho de Melo icsk->icsk_rto, DCCP_RTO_MAX); 5637c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo return 0; 5647c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo} 5657c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 566f21e68caa0ddffddf98a1e729e734a470957b6ecArnaldo Carvalho de MeloEXPORT_SYMBOL_GPL(dccp_connect); 567f21e68caa0ddffddf98a1e729e734a470957b6ecArnaldo Carvalho de Melo 5687c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melovoid dccp_send_ack(struct sock *sk) 5697c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo{ 5707c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* If we have been reset, we may not send again. */ 5717c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo if (sk->sk_state != DCCP_CLOSED) { 572118b2c9532c853ebdf15c21128d30a343b89ea45Arnaldo Carvalho de Melo struct sk_buff *skb = alloc_skb(sk->sk_prot->max_header, 573118b2c9532c853ebdf15c21128d30a343b89ea45Arnaldo Carvalho de Melo GFP_ATOMIC); 5747c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 5757c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo if (skb == NULL) { 5767c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo inet_csk_schedule_ack(sk); 5777c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo inet_csk(sk)->icsk_ack.ato = TCP_ATO_MIN; 5787690af3fff7633e40b1b9950eb8489129251d074Arnaldo Carvalho de Melo inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK, 5797690af3fff7633e40b1b9950eb8489129251d074Arnaldo Carvalho de Melo TCP_DELACK_MAX, 5807690af3fff7633e40b1b9950eb8489129251d074Arnaldo Carvalho de Melo DCCP_RTO_MAX); 5817c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo return; 5827c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo } 5837c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 5847c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* Reserve space for headers */ 585118b2c9532c853ebdf15c21128d30a343b89ea45Arnaldo Carvalho de Melo skb_reserve(skb, sk->sk_prot->max_header); 5867c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_ACK; 5877c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo dccp_transmit_skb(sk, skb); 5887c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo } 5897c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo} 5907c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 5917c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de MeloEXPORT_SYMBOL_GPL(dccp_send_ack); 5927c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 5931e2f0e5e8376f2a0ada8760fc9d3104e1a81382bGerrit Renker#if 0 594727ecc5faaf6e976fc841649821c865ebd1e822dGerrit Renker/* FIXME: Is this still necessary (11.3) - currently nowhere used by DCCP. */ 5957c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melovoid dccp_send_delayed_ack(struct sock *sk) 5967c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo{ 5977c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo struct inet_connection_sock *icsk = inet_csk(sk); 5987c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* 5997c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * FIXME: tune this timer. elapsed time fixes the skew, so no problem 6007c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * with using 2s, and active senders also piggyback the ACK into a 6017c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * DATAACK packet, so this is really for quiescent senders. 6027c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo */ 6037c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo unsigned long timeout = jiffies + 2 * HZ; 6047c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 6057c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* Use new timeout only if there wasn't a older one earlier. */ 6067c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo if (icsk->icsk_ack.pending & ICSK_ACK_TIMER) { 6077c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* If delack timer was blocked or is about to expire, 6087c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * send ACK now. 6097c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * 6107c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * FIXME: check the "about to expire" part 6117c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo */ 6127c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo if (icsk->icsk_ack.blocked) { 6137c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo dccp_send_ack(sk); 6147c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo return; 6157c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo } 6167c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 6177c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo if (!time_before(timeout, icsk->icsk_ack.timeout)) 6187c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo timeout = icsk->icsk_ack.timeout; 6197c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo } 6207c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo icsk->icsk_ack.pending |= ICSK_ACK_SCHED | ICSK_ACK_TIMER; 6217c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo icsk->icsk_ack.timeout = timeout; 6227c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo sk_reset_timer(sk, &icsk->icsk_delack_timer, timeout); 6237c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo} 6241e2f0e5e8376f2a0ada8760fc9d3104e1a81382bGerrit Renker#endif 6257c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 626b0d045ca45a44d9f8bd66d0a10558b10c60f895aGerrit Renkervoid dccp_send_sync(struct sock *sk, const u64 ackno, 627e92ae93a8aa66aea12935420cb22d4df1c18d023Arnaldo Carvalho de Melo const enum dccp_pkt_type pkt_type) 6287c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo{ 6297c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* 6307c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * We are not putting this on the write queue, so 6317c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * dccp_transmit_skb() will set the ownership to this 6327c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo * sock. 6337c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo */ 634118b2c9532c853ebdf15c21128d30a343b89ea45Arnaldo Carvalho de Melo struct sk_buff *skb = alloc_skb(sk->sk_prot->max_header, GFP_ATOMIC); 6357c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 636b0d045ca45a44d9f8bd66d0a10558b10c60f895aGerrit Renker if (skb == NULL) { 6377c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* FIXME: how to make sure the sync is sent? */ 638b0d045ca45a44d9f8bd66d0a10558b10c60f895aGerrit Renker DCCP_CRIT("could not send %s", dccp_packet_name(pkt_type)); 6397c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo return; 640b0d045ca45a44d9f8bd66d0a10558b10c60f895aGerrit Renker } 6417c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 6427c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* Reserve space for headers and prepare control bits. */ 643118b2c9532c853ebdf15c21128d30a343b89ea45Arnaldo Carvalho de Melo skb_reserve(skb, sk->sk_prot->max_header); 644e92ae93a8aa66aea12935420cb22d4df1c18d023Arnaldo Carvalho de Melo DCCP_SKB_CB(skb)->dccpd_type = pkt_type; 645b0d045ca45a44d9f8bd66d0a10558b10c60f895aGerrit Renker DCCP_SKB_CB(skb)->dccpd_ack_seq = ackno; 6467c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 647d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker /* 648d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker * Clear the flag in case the Sync was scheduled for out-of-band data, 649d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker * such as carrying a long Ack Vector. 650d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker */ 651d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker dccp_sk(sk)->dccps_sync_scheduled = 0; 652d83447f0944e73d690218d79c07762ffa4ceb9e4Gerrit Renker 6537c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo dccp_transmit_skb(sk, skb); 6547c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo} 6557c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 656b61fafc4ef3faf54236d57e3b230ca19167663bfArnaldo Carvalho de MeloEXPORT_SYMBOL_GPL(dccp_send_sync); 657b61fafc4ef3faf54236d57e3b230ca19167663bfArnaldo Carvalho de Melo 6587690af3fff7633e40b1b9950eb8489129251d074Arnaldo Carvalho de Melo/* 6597690af3fff7633e40b1b9950eb8489129251d074Arnaldo Carvalho de Melo * Send a DCCP_PKT_CLOSE/CLOSEREQ. The caller locks the socket for us. This 6607690af3fff7633e40b1b9950eb8489129251d074Arnaldo Carvalho de Melo * cannot be allowed to fail queueing a DCCP_PKT_CLOSE/CLOSEREQ frame under 6617690af3fff7633e40b1b9950eb8489129251d074Arnaldo Carvalho de Melo * any circumstances. 6627c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo */ 6637ad07e7cf343181002c10c39d3f57a88e4903d4fArnaldo Carvalho de Melovoid dccp_send_close(struct sock *sk, const int active) 6647c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo{ 6657c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo struct dccp_sock *dp = dccp_sk(sk); 6667c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo struct sk_buff *skb; 6677d877f3bda870ab5f001bd92528654471d5966b3Al Viro const gfp_t prio = active ? GFP_KERNEL : GFP_ATOMIC; 6687c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 6697ad07e7cf343181002c10c39d3f57a88e4903d4fArnaldo Carvalho de Melo skb = alloc_skb(sk->sk_prot->max_header, prio); 6707ad07e7cf343181002c10c39d3f57a88e4903d4fArnaldo Carvalho de Melo if (skb == NULL) 6717ad07e7cf343181002c10c39d3f57a88e4903d4fArnaldo Carvalho de Melo return; 6727c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 6737c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo /* Reserve space for headers and prepare control bits. */ 6747c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo skb_reserve(skb, sk->sk_prot->max_header); 675b8599d20708fa3bde1e414689f3474560c2d990bGerrit Renker if (dp->dccps_role == DCCP_ROLE_SERVER && !dp->dccps_server_timewait) 676b8599d20708fa3bde1e414689f3474560c2d990bGerrit Renker DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_CLOSEREQ; 677b8599d20708fa3bde1e414689f3474560c2d990bGerrit Renker else 678b8599d20708fa3bde1e414689f3474560c2d990bGerrit Renker DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_CLOSE; 6797c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo 6807ad07e7cf343181002c10c39d3f57a88e4903d4fArnaldo Carvalho de Melo if (active) { 68148918a4dbd6c599d6af30bd64cb355fadca708ebHerbert Xu dccp_skb_entail(sk, skb); 6827ad07e7cf343181002c10c39d3f57a88e4903d4fArnaldo Carvalho de Melo dccp_transmit_skb(sk, skb_clone(skb, prio)); 68392d31920b84f258badf206eea8aaf5ac677ac535Gerrit Renker /* 68492d31920b84f258badf206eea8aaf5ac677ac535Gerrit Renker * Retransmission timer for active-close: RFC 4340, 8.3 requires 68592d31920b84f258badf206eea8aaf5ac677ac535Gerrit Renker * to retransmit the Close/CloseReq until the CLOSING/CLOSEREQ 68692d31920b84f258badf206eea8aaf5ac677ac535Gerrit Renker * state can be left. The initial timeout is 2 RTTs. 68792d31920b84f258badf206eea8aaf5ac677ac535Gerrit Renker * Since RTT measurement is done by the CCIDs, there is no easy 68892d31920b84f258badf206eea8aaf5ac677ac535Gerrit Renker * way to get an RTT sample. The fallback RTT from RFC 4340, 3.4 68992d31920b84f258badf206eea8aaf5ac677ac535Gerrit Renker * is too low (200ms); we use a high value to avoid unnecessary 69092d31920b84f258badf206eea8aaf5ac677ac535Gerrit Renker * retransmissions when the link RTT is > 0.2 seconds. 69192d31920b84f258badf206eea8aaf5ac677ac535Gerrit Renker * FIXME: Let main module sample RTTs and use that instead. 69292d31920b84f258badf206eea8aaf5ac677ac535Gerrit Renker */ 69392d31920b84f258badf206eea8aaf5ac677ac535Gerrit Renker inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, 69492d31920b84f258badf206eea8aaf5ac677ac535Gerrit Renker DCCP_TIMEOUT_INIT, DCCP_RTO_MAX); 6957ad07e7cf343181002c10c39d3f57a88e4903d4fArnaldo Carvalho de Melo } else 6967ad07e7cf343181002c10c39d3f57a88e4903d4fArnaldo Carvalho de Melo dccp_transmit_skb(sk, skb); 6977c657876b63cb1d8a2ec06f8fc6c37bb8412e66cArnaldo Carvalho de Melo} 698