1 |
1275 |
phoenix |
/* SCTP kernel reference Implementation
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2 |
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* Copyright (c) 1999-2000 Cisco, Inc.
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3 |
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* Copyright (c) 1999-2001 Motorola, Inc.
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4 |
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* Copyright (c) 2001-2003 International Business Machines, Corp.
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5 |
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* Copyright (c) 2001 Intel Corp.
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6 |
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* Copyright (c) 2001 Nokia, Inc.
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7 |
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* Copyright (c) 2001 La Monte H.P. Yarroll
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8 |
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*
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9 |
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* This file is part of the SCTP kernel reference Implementation
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10 |
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*
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11 |
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* These functions handle all input from the IP layer into SCTP.
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12 |
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*
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13 |
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* The SCTP reference implementation is free software;
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* you can redistribute it and/or modify it under the terms of
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* the GNU General Public License as published by
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* the Free Software Foundation; either version 2, or (at your option)
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* any later version.
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*
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* The SCTP reference implementation is distributed in the hope that it
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* will be useful, but WITHOUT ANY WARRANTY; without even the implied
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* ************************
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* warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
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* See the GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with GNU CC; see the file COPYING. If not, write to
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* the Free Software Foundation, 59 Temple Place - Suite 330,
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* Boston, MA 02111-1307, USA.
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*
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30 |
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* Please send any bug reports or fixes you make to the
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31 |
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* email address(es):
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* lksctp developers <lksctp-developers@lists.sourceforge.net>
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*
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* Or submit a bug report through the following website:
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* http://www.sf.net/projects/lksctp
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*
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* Written or modified by:
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* La Monte H.P. Yarroll <piggy@acm.org>
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39 |
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* Karl Knutson <karl@athena.chicago.il.us>
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40 |
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* Xingang Guo <xingang.guo@intel.com>
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41 |
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* Jon Grimm <jgrimm@us.ibm.com>
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42 |
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* Hui Huang <hui.huang@nokia.com>
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43 |
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* Daisy Chang <daisyc@us.ibm.com>
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44 |
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* Sridhar Samudrala <sri@us.ibm.com>
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45 |
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* Ardelle Fan <ardelle.fan@intel.com>
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46 |
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*
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47 |
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* Any bugs reported given to us we will try to fix... any fixes shared will
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* be incorporated into the next SCTP release.
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*/
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#include <linux/types.h>
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52 |
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#include <linux/list.h> /* For struct list_head */
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53 |
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#include <linux/socket.h>
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54 |
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#include <linux/ip.h>
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55 |
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#include <linux/time.h> /* For struct timeval */
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56 |
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#include <net/ip.h>
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57 |
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#include <net/icmp.h>
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58 |
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#include <net/snmp.h>
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59 |
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#include <net/sock.h>
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60 |
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#include <linux/ipsec.h>
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61 |
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#include <net/sctp/sctp.h>
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62 |
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#include <net/sctp/sm.h>
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63 |
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64 |
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/* Forward declarations for internal helpers. */
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65 |
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static int sctp_rcv_ootb(struct sk_buff *);
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66 |
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struct sctp_association *__sctp_rcv_lookup(struct sk_buff *skb,
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67 |
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const union sctp_addr *laddr,
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68 |
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const union sctp_addr *paddr,
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69 |
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struct sctp_transport **transportp);
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70 |
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struct sctp_endpoint *__sctp_rcv_lookup_endpoint(const union sctp_addr *laddr);
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71 |
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72 |
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73 |
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/* Calculate the SCTP checksum of an SCTP packet. */
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74 |
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static inline int sctp_rcv_checksum(struct sk_buff *skb)
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75 |
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{
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76 |
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struct sctphdr *sh;
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77 |
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__u32 cmp, val;
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78 |
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struct sk_buff *list = skb_shinfo(skb)->frag_list;
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79 |
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80 |
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sh = (struct sctphdr *) skb->h.raw;
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81 |
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cmp = ntohl(sh->checksum);
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82 |
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83 |
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val = sctp_start_cksum((__u8 *)sh, skb_headlen(skb));
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84 |
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|
85 |
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for (; list; list = list->next)
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86 |
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val = sctp_update_cksum((__u8 *)list->data, skb_headlen(list),
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87 |
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val);
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88 |
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|
89 |
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val = sctp_end_cksum(val);
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90 |
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|
91 |
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if (val != cmp) {
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92 |
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/* CRC failure, dump it. */
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93 |
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SCTP_INC_STATS_BH(SctpChecksumErrors);
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94 |
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return -1;
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95 |
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}
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96 |
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return 0;
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97 |
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}
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98 |
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|
99 |
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/*
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100 |
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* This is the routine which IP calls when receiving an SCTP packet.
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101 |
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*/
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102 |
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int sctp_rcv(struct sk_buff *skb)
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103 |
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{
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104 |
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struct sock *sk;
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105 |
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struct sctp_association *asoc;
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106 |
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struct sctp_endpoint *ep = NULL;
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107 |
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struct sctp_ep_common *rcvr;
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108 |
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struct sctp_transport *transport = NULL;
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109 |
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struct sctp_chunk *chunk;
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110 |
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struct sctphdr *sh;
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111 |
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union sctp_addr src;
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112 |
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union sctp_addr dest;
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113 |
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int family;
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114 |
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struct sctp_af *af;
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115 |
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int ret = 0;
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116 |
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117 |
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if (skb->pkt_type!=PACKET_HOST)
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118 |
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goto discard_it;
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119 |
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120 |
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SCTP_INC_STATS_BH(SctpInSCTPPacks);
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121 |
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122 |
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sh = (struct sctphdr *) skb->h.raw;
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123 |
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124 |
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/* Pull up the IP and SCTP headers. */
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125 |
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__skb_pull(skb, skb->h.raw - skb->data);
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126 |
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if (skb->len < sizeof(struct sctphdr))
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127 |
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goto discard_it;
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128 |
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if (sctp_rcv_checksum(skb) < 0)
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129 |
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goto discard_it;
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130 |
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131 |
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skb_pull(skb, sizeof(struct sctphdr));
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132 |
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133 |
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family = ipver2af(skb->nh.iph->version);
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134 |
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af = sctp_get_af_specific(family);
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135 |
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if (unlikely(!af))
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136 |
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goto discard_it;
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137 |
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138 |
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/* Initialize local addresses for lookups. */
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139 |
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af->from_skb(&src, skb, 1);
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140 |
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af->from_skb(&dest, skb, 0);
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141 |
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142 |
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/* If the packet is to or from a non-unicast address,
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143 |
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* silently discard the packet.
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144 |
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*
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145 |
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* This is not clearly defined in the RFC except in section
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146 |
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* 8.4 - OOTB handling. However, based on the book "Stream Control
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147 |
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* Transmission Protocol" 2.1, "It is important to note that the
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148 |
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* IP address of an SCTP transport address must be a routable
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149 |
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* unicast address. In other words, IP multicast addresses and
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150 |
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* IP broadcast addresses cannot be used in an SCTP transport
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151 |
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* address."
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152 |
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*/
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153 |
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if (!af->addr_valid(&src, NULL) || !af->addr_valid(&dest, NULL))
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goto discard_it;
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155 |
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156 |
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asoc = __sctp_rcv_lookup(skb, &src, &dest, &transport);
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158 |
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/*
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159 |
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* RFC 2960, 8.4 - Handle "Out of the blue" Packets.
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160 |
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* An SCTP packet is called an "out of the blue" (OOTB)
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161 |
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* packet if it is correctly formed, i.e., passed the
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162 |
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* receiver's checksum check, but the receiver is not
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163 |
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* able to identify the association to which this
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164 |
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* packet belongs.
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165 |
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*/
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166 |
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if (!asoc) {
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167 |
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ep = __sctp_rcv_lookup_endpoint(&dest);
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168 |
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if (sctp_rcv_ootb(skb)) {
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169 |
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SCTP_INC_STATS_BH(SctpOutOfBlues);
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170 |
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goto discard_release;
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171 |
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}
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172 |
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}
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173 |
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174 |
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/* Retrieve the common input handling substructure. */
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175 |
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rcvr = asoc ? &asoc->base : &ep->base;
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176 |
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sk = rcvr->sk;
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177 |
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178 |
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if (!ipsec_sk_policy(sk, skb))
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179 |
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goto discard_release;
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180 |
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181 |
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ret = sk_filter(sk, skb, 1);
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182 |
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if (ret)
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183 |
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goto discard_release;
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184 |
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185 |
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/* Create an SCTP packet structure. */
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186 |
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chunk = sctp_chunkify(skb, asoc, sk);
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187 |
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if (!chunk) {
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188 |
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ret = -ENOMEM;
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189 |
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goto discard_release;
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190 |
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}
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191 |
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|
192 |
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/* Remember what endpoint is to handle this packet. */
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193 |
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chunk->rcvr = rcvr;
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194 |
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|
195 |
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/* Remember the SCTP header. */
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196 |
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chunk->sctp_hdr = sh;
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197 |
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|
198 |
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/* Set the source and destination addresses of the incoming chunk. */
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199 |
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sctp_init_addrs(chunk, &src, &dest);
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200 |
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|
201 |
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/* Remember where we came from. */
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202 |
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chunk->transport = transport;
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203 |
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|
204 |
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/* Acquire access to the sock lock. Note: We are safe from other
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205 |
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* bottom halves on this lock, but a user may be in the lock too,
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206 |
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* so check if it is busy.
|
207 |
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*/
|
208 |
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sctp_bh_lock_sock(sk);
|
209 |
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|
210 |
|
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if (sock_owned_by_user(sk))
|
211 |
|
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sk_add_backlog(sk, (struct sk_buff *) chunk);
|
212 |
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else
|
213 |
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sctp_backlog_rcv(sk, (struct sk_buff *) chunk);
|
214 |
|
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|
215 |
|
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/* Release the sock and any reference counts we took in the
|
216 |
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* lookup calls.
|
217 |
|
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*/
|
218 |
|
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sctp_bh_unlock_sock(sk);
|
219 |
|
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if (asoc)
|
220 |
|
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sctp_association_put(asoc);
|
221 |
|
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else
|
222 |
|
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sctp_endpoint_put(ep);
|
223 |
|
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sock_put(sk);
|
224 |
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return ret;
|
225 |
|
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|
226 |
|
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discard_it:
|
227 |
|
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kfree_skb(skb);
|
228 |
|
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return ret;
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229 |
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|
230 |
|
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discard_release:
|
231 |
|
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/* Release any structures we may be holding. */
|
232 |
|
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if (asoc) {
|
233 |
|
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sock_put(asoc->base.sk);
|
234 |
|
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sctp_association_put(asoc);
|
235 |
|
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} else {
|
236 |
|
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sock_put(ep->base.sk);
|
237 |
|
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sctp_endpoint_put(ep);
|
238 |
|
|
}
|
239 |
|
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|
240 |
|
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goto discard_it;
|
241 |
|
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}
|
242 |
|
|
|
243 |
|
|
/* Handle second half of inbound skb processing. If the sock was busy,
|
244 |
|
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* we may have need to delay processing until later when the sock is
|
245 |
|
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* released (on the backlog). If not busy, we call this routine
|
246 |
|
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* directly from the bottom half.
|
247 |
|
|
*/
|
248 |
|
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int sctp_backlog_rcv(struct sock *sk, struct sk_buff *skb)
|
249 |
|
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{
|
250 |
|
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struct sctp_chunk *chunk;
|
251 |
|
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struct sctp_inq *inqueue;
|
252 |
|
|
|
253 |
|
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/* One day chunk will live inside the skb, but for
|
254 |
|
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* now this works.
|
255 |
|
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*/
|
256 |
|
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chunk = (struct sctp_chunk *) skb;
|
257 |
|
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inqueue = &chunk->rcvr->inqueue;
|
258 |
|
|
|
259 |
|
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sctp_inq_push(inqueue, chunk);
|
260 |
|
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return 0;
|
261 |
|
|
}
|
262 |
|
|
|
263 |
|
|
/* Handle icmp frag needed error. */
|
264 |
|
|
void sctp_icmp_frag_needed(struct sock *sk, struct sctp_association *asoc,
|
265 |
|
|
struct sctp_transport *t, __u32 pmtu)
|
266 |
|
|
{
|
267 |
|
|
if (unlikely(pmtu < SCTP_DEFAULT_MINSEGMENT)) {
|
268 |
|
|
printk(KERN_WARNING "%s: Reported pmtu %d too low, "
|
269 |
|
|
"using default minimum of %d\n", __FUNCTION__, pmtu,
|
270 |
|
|
SCTP_DEFAULT_MINSEGMENT);
|
271 |
|
|
pmtu = SCTP_DEFAULT_MINSEGMENT;
|
272 |
|
|
}
|
273 |
|
|
|
274 |
|
|
if (!sock_owned_by_user(sk) && t && (t->pmtu != pmtu)) {
|
275 |
|
|
t->pmtu = pmtu;
|
276 |
|
|
sctp_assoc_sync_pmtu(asoc);
|
277 |
|
|
sctp_retransmit(&asoc->outqueue, t, SCTP_RTXR_PMTUD);
|
278 |
|
|
}
|
279 |
|
|
}
|
280 |
|
|
|
281 |
|
|
/* Common lookup code for icmp/icmpv6 error handler. */
|
282 |
|
|
struct sock *sctp_err_lookup(int family, struct sk_buff *skb,
|
283 |
|
|
struct sctphdr *sctphdr,
|
284 |
|
|
struct sctp_endpoint **epp,
|
285 |
|
|
struct sctp_association **app,
|
286 |
|
|
struct sctp_transport **tpp)
|
287 |
|
|
{
|
288 |
|
|
union sctp_addr saddr;
|
289 |
|
|
union sctp_addr daddr;
|
290 |
|
|
struct sctp_af *af;
|
291 |
|
|
struct sock *sk = NULL;
|
292 |
|
|
struct sctp_endpoint *ep = NULL;
|
293 |
|
|
struct sctp_association *asoc = NULL;
|
294 |
|
|
struct sctp_transport *transport = NULL;
|
295 |
|
|
|
296 |
|
|
*app = NULL; *epp = NULL; *tpp = NULL;
|
297 |
|
|
|
298 |
|
|
af = sctp_get_af_specific(family);
|
299 |
|
|
if (unlikely(!af)) {
|
300 |
|
|
return NULL;
|
301 |
|
|
}
|
302 |
|
|
|
303 |
|
|
/* Initialize local addresses for lookups. */
|
304 |
|
|
af->from_skb(&saddr, skb, 1);
|
305 |
|
|
af->from_skb(&daddr, skb, 0);
|
306 |
|
|
|
307 |
|
|
/* Look for an association that matches the incoming ICMP error
|
308 |
|
|
* packet.
|
309 |
|
|
*/
|
310 |
|
|
asoc = __sctp_lookup_association(&saddr, &daddr, &transport);
|
311 |
|
|
if (!asoc) {
|
312 |
|
|
/* If there is no matching association, see if it matches any
|
313 |
|
|
* endpoint. This may happen for an ICMP error generated in
|
314 |
|
|
* response to an INIT_ACK.
|
315 |
|
|
*/
|
316 |
|
|
ep = __sctp_rcv_lookup_endpoint(&daddr);
|
317 |
|
|
if (!ep) {
|
318 |
|
|
return NULL;
|
319 |
|
|
}
|
320 |
|
|
}
|
321 |
|
|
|
322 |
|
|
if (asoc) {
|
323 |
|
|
if (ntohl(sctphdr->vtag) != asoc->c.peer_vtag) {
|
324 |
|
|
ICMP_INC_STATS_BH(IcmpInErrors);
|
325 |
|
|
goto out;
|
326 |
|
|
}
|
327 |
|
|
sk = asoc->base.sk;
|
328 |
|
|
} else
|
329 |
|
|
sk = ep->base.sk;
|
330 |
|
|
|
331 |
|
|
sctp_bh_lock_sock(sk);
|
332 |
|
|
|
333 |
|
|
/* If too many ICMPs get dropped on busy
|
334 |
|
|
* servers this needs to be solved differently.
|
335 |
|
|
*/
|
336 |
|
|
if (sock_owned_by_user(sk))
|
337 |
|
|
NET_INC_STATS_BH(LockDroppedIcmps);
|
338 |
|
|
|
339 |
|
|
*epp = ep;
|
340 |
|
|
*app = asoc;
|
341 |
|
|
*tpp = transport;
|
342 |
|
|
return sk;
|
343 |
|
|
|
344 |
|
|
out:
|
345 |
|
|
sock_put(sk);
|
346 |
|
|
if (asoc)
|
347 |
|
|
sctp_association_put(asoc);
|
348 |
|
|
if (ep)
|
349 |
|
|
sctp_endpoint_put(ep);
|
350 |
|
|
return NULL;
|
351 |
|
|
}
|
352 |
|
|
|
353 |
|
|
/* Common cleanup code for icmp/icmpv6 error handler. */
|
354 |
|
|
void sctp_err_finish(struct sock *sk, struct sctp_endpoint *ep,
|
355 |
|
|
struct sctp_association *asoc)
|
356 |
|
|
{
|
357 |
|
|
sctp_bh_unlock_sock(sk);
|
358 |
|
|
sock_put(sk);
|
359 |
|
|
if (asoc)
|
360 |
|
|
sctp_association_put(asoc);
|
361 |
|
|
if (ep)
|
362 |
|
|
sctp_endpoint_put(ep);
|
363 |
|
|
}
|
364 |
|
|
|
365 |
|
|
/*
|
366 |
|
|
* This routine is called by the ICMP module when it gets some
|
367 |
|
|
* sort of error condition. If err < 0 then the socket should
|
368 |
|
|
* be closed and the error returned to the user. If err > 0
|
369 |
|
|
* it's just the icmp type << 8 | icmp code. After adjustment
|
370 |
|
|
* header points to the first 8 bytes of the sctp header. We need
|
371 |
|
|
* to find the appropriate port.
|
372 |
|
|
*
|
373 |
|
|
* The locking strategy used here is very "optimistic". When
|
374 |
|
|
* someone else accesses the socket the ICMP is just dropped
|
375 |
|
|
* and for some paths there is no check at all.
|
376 |
|
|
* A more general error queue to queue errors for later handling
|
377 |
|
|
* is probably better.
|
378 |
|
|
*
|
379 |
|
|
*/
|
380 |
|
|
void sctp_v4_err(struct sk_buff *skb, __u32 info)
|
381 |
|
|
{
|
382 |
|
|
struct iphdr *iph = (struct iphdr *)skb->data;
|
383 |
|
|
struct sctphdr *sh = (struct sctphdr *)(skb->data + (iph->ihl <<2));
|
384 |
|
|
int type = skb->h.icmph->type;
|
385 |
|
|
int code = skb->h.icmph->code;
|
386 |
|
|
struct sock *sk;
|
387 |
|
|
struct sctp_endpoint *ep;
|
388 |
|
|
struct sctp_association *asoc;
|
389 |
|
|
struct sctp_transport *transport;
|
390 |
|
|
struct inet_opt *inet;
|
391 |
|
|
char *saveip, *savesctp;
|
392 |
|
|
int err;
|
393 |
|
|
|
394 |
|
|
if (skb->len < ((iph->ihl << 2) + 8)) {
|
395 |
|
|
ICMP_INC_STATS_BH(IcmpInErrors);
|
396 |
|
|
return;
|
397 |
|
|
}
|
398 |
|
|
|
399 |
|
|
/* Fix up skb to look at the embedded net header. */
|
400 |
|
|
saveip = skb->nh.raw;
|
401 |
|
|
savesctp = skb->h.raw;
|
402 |
|
|
skb->nh.iph = iph;
|
403 |
|
|
skb->h.raw = (char *)sh;
|
404 |
|
|
sk = sctp_err_lookup(AF_INET, skb, sh, &ep, &asoc, &transport);
|
405 |
|
|
/* Put back, the original pointers. */
|
406 |
|
|
skb->nh.raw = saveip;
|
407 |
|
|
skb->h.raw = savesctp;
|
408 |
|
|
if (!sk) {
|
409 |
|
|
ICMP_INC_STATS_BH(IcmpInErrors);
|
410 |
|
|
return;
|
411 |
|
|
}
|
412 |
|
|
/* Warning: The sock lock is held. Remember to call
|
413 |
|
|
* sctp_err_finish!
|
414 |
|
|
*/
|
415 |
|
|
|
416 |
|
|
switch (type) {
|
417 |
|
|
case ICMP_PARAMETERPROB:
|
418 |
|
|
err = EPROTO;
|
419 |
|
|
break;
|
420 |
|
|
case ICMP_DEST_UNREACH:
|
421 |
|
|
if (code > NR_ICMP_UNREACH)
|
422 |
|
|
goto out_unlock;
|
423 |
|
|
|
424 |
|
|
/* PMTU discovery (RFC1191) */
|
425 |
|
|
if (ICMP_FRAG_NEEDED == code) {
|
426 |
|
|
sctp_icmp_frag_needed(sk, asoc, transport, info);
|
427 |
|
|
goto out_unlock;
|
428 |
|
|
}
|
429 |
|
|
|
430 |
|
|
err = icmp_err_convert[code].errno;
|
431 |
|
|
break;
|
432 |
|
|
case ICMP_TIME_EXCEEDED:
|
433 |
|
|
/* Ignore any time exceeded errors due to fragment reassembly
|
434 |
|
|
* timeouts.
|
435 |
|
|
*/
|
436 |
|
|
if (ICMP_EXC_FRAGTIME == code)
|
437 |
|
|
goto out_unlock;
|
438 |
|
|
|
439 |
|
|
err = EHOSTUNREACH;
|
440 |
|
|
break;
|
441 |
|
|
default:
|
442 |
|
|
goto out_unlock;
|
443 |
|
|
}
|
444 |
|
|
|
445 |
|
|
inet = inet_sk(sk);
|
446 |
|
|
if (!sock_owned_by_user(sk) && inet->recverr) {
|
447 |
|
|
sk->sk_err = err;
|
448 |
|
|
sk->sk_error_report(sk);
|
449 |
|
|
} else { /* Only an error on timeout */
|
450 |
|
|
sk->sk_err_soft = err;
|
451 |
|
|
}
|
452 |
|
|
|
453 |
|
|
out_unlock:
|
454 |
|
|
sctp_err_finish(sk, ep, asoc);
|
455 |
|
|
}
|
456 |
|
|
|
457 |
|
|
/*
|
458 |
|
|
* RFC 2960, 8.4 - Handle "Out of the blue" Packets.
|
459 |
|
|
*
|
460 |
|
|
* This function scans all the chunks in the OOTB packet to determine if
|
461 |
|
|
* the packet should be discarded right away. If a response might be needed
|
462 |
|
|
* for this packet, or, if further processing is possible, the packet will
|
463 |
|
|
* be queued to a proper inqueue for the next phase of handling.
|
464 |
|
|
*
|
465 |
|
|
* Output:
|
466 |
|
|
* Return 0 - If further processing is needed.
|
467 |
|
|
* Return 1 - If the packet can be discarded right away.
|
468 |
|
|
*/
|
469 |
|
|
int sctp_rcv_ootb(struct sk_buff *skb)
|
470 |
|
|
{
|
471 |
|
|
sctp_chunkhdr_t *ch;
|
472 |
|
|
__u8 *ch_end;
|
473 |
|
|
sctp_errhdr_t *err;
|
474 |
|
|
|
475 |
|
|
ch = (sctp_chunkhdr_t *) skb->data;
|
476 |
|
|
|
477 |
|
|
/* Scan through all the chunks in the packet. */
|
478 |
|
|
do {
|
479 |
|
|
ch_end = ((__u8 *) ch) + WORD_ROUND(ntohs(ch->length));
|
480 |
|
|
|
481 |
|
|
/* RFC 8.4, 2) If the OOTB packet contains an ABORT chunk, the
|
482 |
|
|
* receiver MUST silently discard the OOTB packet and take no
|
483 |
|
|
* further action.
|
484 |
|
|
*/
|
485 |
|
|
if (SCTP_CID_ABORT == ch->type)
|
486 |
|
|
goto discard;
|
487 |
|
|
|
488 |
|
|
/* RFC 8.4, 6) If the packet contains a SHUTDOWN COMPLETE
|
489 |
|
|
* chunk, the receiver should silently discard the packet
|
490 |
|
|
* and take no further action.
|
491 |
|
|
*/
|
492 |
|
|
if (SCTP_CID_SHUTDOWN_COMPLETE == ch->type)
|
493 |
|
|
goto discard;
|
494 |
|
|
|
495 |
|
|
/* RFC 8.4, 7) If the packet contains a "Stale cookie" ERROR
|
496 |
|
|
* or a COOKIE ACK the SCTP Packet should be silently
|
497 |
|
|
* discarded.
|
498 |
|
|
*/
|
499 |
|
|
if (SCTP_CID_COOKIE_ACK == ch->type)
|
500 |
|
|
goto discard;
|
501 |
|
|
|
502 |
|
|
if (SCTP_CID_ERROR == ch->type) {
|
503 |
|
|
sctp_walk_errors(err, ch) {
|
504 |
|
|
if (SCTP_ERROR_STALE_COOKIE == err->cause)
|
505 |
|
|
goto discard;
|
506 |
|
|
}
|
507 |
|
|
}
|
508 |
|
|
|
509 |
|
|
ch = (sctp_chunkhdr_t *) ch_end;
|
510 |
|
|
} while (ch_end < skb->tail);
|
511 |
|
|
|
512 |
|
|
return 0;
|
513 |
|
|
|
514 |
|
|
discard:
|
515 |
|
|
return 1;
|
516 |
|
|
}
|
517 |
|
|
|
518 |
|
|
/* Insert endpoint into the hash table. */
|
519 |
|
|
void __sctp_hash_endpoint(struct sctp_endpoint *ep)
|
520 |
|
|
{
|
521 |
|
|
struct sctp_ep_common **epp;
|
522 |
|
|
struct sctp_ep_common *epb;
|
523 |
|
|
struct sctp_hashbucket *head;
|
524 |
|
|
|
525 |
|
|
epb = &ep->base;
|
526 |
|
|
|
527 |
|
|
epb->hashent = sctp_ep_hashfn(epb->bind_addr.port);
|
528 |
|
|
head = &sctp_ep_hashtable[epb->hashent];
|
529 |
|
|
|
530 |
|
|
sctp_write_lock(&head->lock);
|
531 |
|
|
epp = &head->chain;
|
532 |
|
|
epb->next = *epp;
|
533 |
|
|
if (epb->next)
|
534 |
|
|
(*epp)->pprev = &epb->next;
|
535 |
|
|
*epp = epb;
|
536 |
|
|
epb->pprev = epp;
|
537 |
|
|
sctp_write_unlock(&head->lock);
|
538 |
|
|
}
|
539 |
|
|
|
540 |
|
|
/* Add an endpoint to the hash. Local BH-safe. */
|
541 |
|
|
void sctp_hash_endpoint(struct sctp_endpoint *ep)
|
542 |
|
|
{
|
543 |
|
|
sctp_local_bh_disable();
|
544 |
|
|
__sctp_hash_endpoint(ep);
|
545 |
|
|
sctp_local_bh_enable();
|
546 |
|
|
}
|
547 |
|
|
|
548 |
|
|
/* Remove endpoint from the hash table. */
|
549 |
|
|
void __sctp_unhash_endpoint(struct sctp_endpoint *ep)
|
550 |
|
|
{
|
551 |
|
|
struct sctp_hashbucket *head;
|
552 |
|
|
struct sctp_ep_common *epb;
|
553 |
|
|
|
554 |
|
|
epb = &ep->base;
|
555 |
|
|
|
556 |
|
|
epb->hashent = sctp_ep_hashfn(epb->bind_addr.port);
|
557 |
|
|
|
558 |
|
|
head = &sctp_ep_hashtable[epb->hashent];
|
559 |
|
|
|
560 |
|
|
sctp_write_lock(&head->lock);
|
561 |
|
|
|
562 |
|
|
if (epb->pprev) {
|
563 |
|
|
if (epb->next)
|
564 |
|
|
epb->next->pprev = epb->pprev;
|
565 |
|
|
*epb->pprev = epb->next;
|
566 |
|
|
epb->pprev = NULL;
|
567 |
|
|
}
|
568 |
|
|
|
569 |
|
|
sctp_write_unlock(&head->lock);
|
570 |
|
|
}
|
571 |
|
|
|
572 |
|
|
/* Remove endpoint from the hash. Local BH-safe. */
|
573 |
|
|
void sctp_unhash_endpoint(struct sctp_endpoint *ep)
|
574 |
|
|
{
|
575 |
|
|
sctp_local_bh_disable();
|
576 |
|
|
__sctp_unhash_endpoint(ep);
|
577 |
|
|
sctp_local_bh_enable();
|
578 |
|
|
}
|
579 |
|
|
|
580 |
|
|
/* Look up an endpoint. */
|
581 |
|
|
struct sctp_endpoint *__sctp_rcv_lookup_endpoint(const union sctp_addr *laddr)
|
582 |
|
|
{
|
583 |
|
|
struct sctp_hashbucket *head;
|
584 |
|
|
struct sctp_ep_common *epb;
|
585 |
|
|
struct sctp_endpoint *ep;
|
586 |
|
|
int hash;
|
587 |
|
|
|
588 |
|
|
hash = sctp_ep_hashfn(laddr->v4.sin_port);
|
589 |
|
|
head = &sctp_ep_hashtable[hash];
|
590 |
|
|
read_lock(&head->lock);
|
591 |
|
|
for (epb = head->chain; epb; epb = epb->next) {
|
592 |
|
|
ep = sctp_ep(epb);
|
593 |
|
|
if (sctp_endpoint_is_match(ep, laddr))
|
594 |
|
|
goto hit;
|
595 |
|
|
}
|
596 |
|
|
|
597 |
|
|
ep = sctp_sk((sctp_get_ctl_sock()))->ep;
|
598 |
|
|
epb = &ep->base;
|
599 |
|
|
|
600 |
|
|
hit:
|
601 |
|
|
sctp_endpoint_hold(ep);
|
602 |
|
|
sock_hold(epb->sk);
|
603 |
|
|
read_unlock(&head->lock);
|
604 |
|
|
return ep;
|
605 |
|
|
}
|
606 |
|
|
|
607 |
|
|
/* Add an association to the hash. Local BH-safe. */
|
608 |
|
|
void sctp_hash_established(struct sctp_association *asoc)
|
609 |
|
|
{
|
610 |
|
|
sctp_local_bh_disable();
|
611 |
|
|
__sctp_hash_established(asoc);
|
612 |
|
|
sctp_local_bh_enable();
|
613 |
|
|
}
|
614 |
|
|
|
615 |
|
|
/* Insert association into the hash table. */
|
616 |
|
|
void __sctp_hash_established(struct sctp_association *asoc)
|
617 |
|
|
{
|
618 |
|
|
struct sctp_ep_common **epp;
|
619 |
|
|
struct sctp_ep_common *epb;
|
620 |
|
|
struct sctp_hashbucket *head;
|
621 |
|
|
|
622 |
|
|
epb = &asoc->base;
|
623 |
|
|
|
624 |
|
|
/* Calculate which chain this entry will belong to. */
|
625 |
|
|
epb->hashent = sctp_assoc_hashfn(epb->bind_addr.port, asoc->peer.port);
|
626 |
|
|
|
627 |
|
|
head = &sctp_assoc_hashtable[epb->hashent];
|
628 |
|
|
|
629 |
|
|
sctp_write_lock(&head->lock);
|
630 |
|
|
epp = &head->chain;
|
631 |
|
|
epb->next = *epp;
|
632 |
|
|
if (epb->next)
|
633 |
|
|
(*epp)->pprev = &epb->next;
|
634 |
|
|
*epp = epb;
|
635 |
|
|
epb->pprev = epp;
|
636 |
|
|
sctp_write_unlock(&head->lock);
|
637 |
|
|
}
|
638 |
|
|
|
639 |
|
|
/* Remove association from the hash table. Local BH-safe. */
|
640 |
|
|
void sctp_unhash_established(struct sctp_association *asoc)
|
641 |
|
|
{
|
642 |
|
|
sctp_local_bh_disable();
|
643 |
|
|
__sctp_unhash_established(asoc);
|
644 |
|
|
sctp_local_bh_enable();
|
645 |
|
|
}
|
646 |
|
|
|
647 |
|
|
/* Remove association from the hash table. */
|
648 |
|
|
void __sctp_unhash_established(struct sctp_association *asoc)
|
649 |
|
|
{
|
650 |
|
|
struct sctp_hashbucket *head;
|
651 |
|
|
struct sctp_ep_common *epb;
|
652 |
|
|
|
653 |
|
|
epb = &asoc->base;
|
654 |
|
|
|
655 |
|
|
epb->hashent = sctp_assoc_hashfn(epb->bind_addr.port,
|
656 |
|
|
asoc->peer.port);
|
657 |
|
|
|
658 |
|
|
head = &sctp_assoc_hashtable[epb->hashent];
|
659 |
|
|
|
660 |
|
|
sctp_write_lock(&head->lock);
|
661 |
|
|
|
662 |
|
|
if (epb->pprev) {
|
663 |
|
|
if (epb->next)
|
664 |
|
|
epb->next->pprev = epb->pprev;
|
665 |
|
|
*epb->pprev = epb->next;
|
666 |
|
|
epb->pprev = NULL;
|
667 |
|
|
}
|
668 |
|
|
|
669 |
|
|
sctp_write_unlock(&head->lock);
|
670 |
|
|
}
|
671 |
|
|
|
672 |
|
|
/* Look up an association. */
|
673 |
|
|
struct sctp_association *__sctp_lookup_association(
|
674 |
|
|
const union sctp_addr *local,
|
675 |
|
|
const union sctp_addr *peer,
|
676 |
|
|
struct sctp_transport **pt)
|
677 |
|
|
{
|
678 |
|
|
struct sctp_hashbucket *head;
|
679 |
|
|
struct sctp_ep_common *epb;
|
680 |
|
|
struct sctp_association *asoc;
|
681 |
|
|
struct sctp_transport *transport;
|
682 |
|
|
int hash;
|
683 |
|
|
|
684 |
|
|
/* Optimize here for direct hit, only listening connections can
|
685 |
|
|
* have wildcards anyways.
|
686 |
|
|
*/
|
687 |
|
|
hash = sctp_assoc_hashfn(local->v4.sin_port, peer->v4.sin_port);
|
688 |
|
|
head = &sctp_assoc_hashtable[hash];
|
689 |
|
|
read_lock(&head->lock);
|
690 |
|
|
for (epb = head->chain; epb; epb = epb->next) {
|
691 |
|
|
asoc = sctp_assoc(epb);
|
692 |
|
|
transport = sctp_assoc_is_match(asoc, local, peer);
|
693 |
|
|
if (transport)
|
694 |
|
|
goto hit;
|
695 |
|
|
}
|
696 |
|
|
|
697 |
|
|
read_unlock(&head->lock);
|
698 |
|
|
|
699 |
|
|
return NULL;
|
700 |
|
|
|
701 |
|
|
hit:
|
702 |
|
|
*pt = transport;
|
703 |
|
|
sctp_association_hold(asoc);
|
704 |
|
|
sock_hold(epb->sk);
|
705 |
|
|
read_unlock(&head->lock);
|
706 |
|
|
return asoc;
|
707 |
|
|
}
|
708 |
|
|
|
709 |
|
|
/* Look up an association. BH-safe. */
|
710 |
|
|
struct sctp_association *sctp_lookup_association(const union sctp_addr *laddr,
|
711 |
|
|
const union sctp_addr *paddr,
|
712 |
|
|
struct sctp_transport **transportp)
|
713 |
|
|
{
|
714 |
|
|
struct sctp_association *asoc;
|
715 |
|
|
|
716 |
|
|
sctp_local_bh_disable();
|
717 |
|
|
asoc = __sctp_lookup_association(laddr, paddr, transportp);
|
718 |
|
|
sctp_local_bh_enable();
|
719 |
|
|
|
720 |
|
|
return asoc;
|
721 |
|
|
}
|
722 |
|
|
|
723 |
|
|
/* Is there an association matching the given local and peer addresses? */
|
724 |
|
|
int sctp_has_association(const union sctp_addr *laddr,
|
725 |
|
|
const union sctp_addr *paddr)
|
726 |
|
|
{
|
727 |
|
|
struct sctp_association *asoc;
|
728 |
|
|
struct sctp_transport *transport;
|
729 |
|
|
|
730 |
|
|
if ((asoc = sctp_lookup_association(laddr, paddr, &transport))) {
|
731 |
|
|
sock_put(asoc->base.sk);
|
732 |
|
|
sctp_association_put(asoc);
|
733 |
|
|
return 1;
|
734 |
|
|
}
|
735 |
|
|
|
736 |
|
|
return 0;
|
737 |
|
|
}
|
738 |
|
|
|
739 |
|
|
/*
|
740 |
|
|
* SCTP Implementors Guide, 2.18 Handling of address
|
741 |
|
|
* parameters within the INIT or INIT-ACK.
|
742 |
|
|
*
|
743 |
|
|
* D) When searching for a matching TCB upon reception of an INIT
|
744 |
|
|
* or INIT-ACK chunk the receiver SHOULD use not only the
|
745 |
|
|
* source address of the packet (containing the INIT or
|
746 |
|
|
* INIT-ACK) but the receiver SHOULD also use all valid
|
747 |
|
|
* address parameters contained within the chunk.
|
748 |
|
|
*
|
749 |
|
|
* 2.18.3 Solution description
|
750 |
|
|
*
|
751 |
|
|
* This new text clearly specifies to an implementor the need
|
752 |
|
|
* to look within the INIT or INIT-ACK. Any implementation that
|
753 |
|
|
* does not do this, may not be able to establish associations
|
754 |
|
|
* in certain circumstances.
|
755 |
|
|
*
|
756 |
|
|
*/
|
757 |
|
|
static struct sctp_association *__sctp_rcv_init_lookup(struct sk_buff *skb,
|
758 |
|
|
const union sctp_addr *laddr, struct sctp_transport **transportp)
|
759 |
|
|
{
|
760 |
|
|
struct sctp_association *asoc;
|
761 |
|
|
union sctp_addr addr;
|
762 |
|
|
union sctp_addr *paddr = &addr;
|
763 |
|
|
struct sctphdr *sh = (struct sctphdr *) skb->h.raw;
|
764 |
|
|
sctp_chunkhdr_t *ch;
|
765 |
|
|
union sctp_params params;
|
766 |
|
|
sctp_init_chunk_t *init;
|
767 |
|
|
struct sctp_transport *transport;
|
768 |
|
|
struct sctp_af *af;
|
769 |
|
|
|
770 |
|
|
ch = (sctp_chunkhdr_t *) skb->data;
|
771 |
|
|
|
772 |
|
|
/* If this is INIT/INIT-ACK look inside the chunk too. */
|
773 |
|
|
switch (ch->type) {
|
774 |
|
|
case SCTP_CID_INIT:
|
775 |
|
|
case SCTP_CID_INIT_ACK:
|
776 |
|
|
break;
|
777 |
|
|
default:
|
778 |
|
|
return NULL;
|
779 |
|
|
}
|
780 |
|
|
|
781 |
|
|
/*
|
782 |
|
|
* This code will NOT touch anything inside the chunk--it is
|
783 |
|
|
* strictly READ-ONLY.
|
784 |
|
|
*
|
785 |
|
|
* RFC 2960 3 SCTP packet Format
|
786 |
|
|
*
|
787 |
|
|
* Multiple chunks can be bundled into one SCTP packet up to
|
788 |
|
|
* the MTU size, except for the INIT, INIT ACK, and SHUTDOWN
|
789 |
|
|
* COMPLETE chunks. These chunks MUST NOT be bundled with any
|
790 |
|
|
* other chunk in a packet. See Section 6.10 for more details
|
791 |
|
|
* on chunk bundling.
|
792 |
|
|
*/
|
793 |
|
|
|
794 |
|
|
/* Find the start of the TLVs and the end of the chunk. This is
|
795 |
|
|
* the region we search for address parameters.
|
796 |
|
|
*/
|
797 |
|
|
init = (sctp_init_chunk_t *)skb->data;
|
798 |
|
|
|
799 |
|
|
/* Walk the parameters looking for embedded addresses. */
|
800 |
|
|
sctp_walk_params(params, init, init_hdr.params) {
|
801 |
|
|
|
802 |
|
|
/* Note: Ignoring hostname addresses. */
|
803 |
|
|
af = sctp_get_af_specific(param_type2af(params.p->type));
|
804 |
|
|
if (!af)
|
805 |
|
|
continue;
|
806 |
|
|
|
807 |
|
|
af->from_addr_param(paddr, params.addr, ntohs(sh->source), 0);
|
808 |
|
|
|
809 |
|
|
asoc = __sctp_lookup_association(laddr, paddr, &transport);
|
810 |
|
|
if (asoc)
|
811 |
|
|
return asoc;
|
812 |
|
|
}
|
813 |
|
|
|
814 |
|
|
return NULL;
|
815 |
|
|
}
|
816 |
|
|
|
817 |
|
|
/* Lookup an association for an inbound skb. */
|
818 |
|
|
struct sctp_association *__sctp_rcv_lookup(struct sk_buff *skb,
|
819 |
|
|
const union sctp_addr *paddr,
|
820 |
|
|
const union sctp_addr *laddr,
|
821 |
|
|
struct sctp_transport **transportp)
|
822 |
|
|
{
|
823 |
|
|
struct sctp_association *asoc;
|
824 |
|
|
|
825 |
|
|
asoc = __sctp_lookup_association(laddr, paddr, transportp);
|
826 |
|
|
|
827 |
|
|
/* Further lookup for INIT/INIT-ACK packets.
|
828 |
|
|
* SCTP Implementors Guide, 2.18 Handling of address
|
829 |
|
|
* parameters within the INIT or INIT-ACK.
|
830 |
|
|
*/
|
831 |
|
|
if (!asoc)
|
832 |
|
|
asoc = __sctp_rcv_init_lookup(skb, laddr, transportp);
|
833 |
|
|
|
834 |
|
|
return asoc;
|
835 |
|
|
}
|