^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0-or-later
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /* SCTP kernel implementation
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * Copyright (c) 1999-2000 Cisco, Inc.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) * Copyright (c) 1999-2001 Motorola, Inc.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Copyright (c) 2001-2003 International Business Machines, Corp.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) * Copyright (c) 2001 Intel Corp.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) * Copyright (c) 2001 Nokia, Inc.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) * Copyright (c) 2001 La Monte H.P. Yarroll
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) * This file is part of the SCTP kernel implementation
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) * These functions handle all input from the IP layer into SCTP.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) * Please send any bug reports or fixes you make to the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) * email address(es):
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) * lksctp developers <linux-sctp@vger.kernel.org>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) * Written or modified by:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) * La Monte H.P. Yarroll <piggy@acm.org>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) * Karl Knutson <karl@athena.chicago.il.us>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) * Xingang Guo <xingang.guo@intel.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) * Jon Grimm <jgrimm@us.ibm.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) * Hui Huang <hui.huang@nokia.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) * Daisy Chang <daisyc@us.ibm.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) * Sridhar Samudrala <sri@us.ibm.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) * Ardelle Fan <ardelle.fan@intel.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) #include <linux/types.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) #include <linux/list.h> /* For struct list_head */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) #include <linux/socket.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) #include <linux/ip.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) #include <linux/time.h> /* For struct timeval */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) #include <net/ip.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) #include <net/icmp.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) #include <net/snmp.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) #include <net/sock.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) #include <net/xfrm.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) #include <net/sctp/sctp.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) #include <net/sctp/sm.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) #include <net/sctp/checksum.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) #include <net/net_namespace.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) #include <linux/rhashtable.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) #include <net/sock_reuseport.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) /* Forward declarations for internal helpers. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) static int sctp_rcv_ootb(struct sk_buff *);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) static struct sctp_association *__sctp_rcv_lookup(struct net *net,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) struct sk_buff *skb,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) const union sctp_addr *paddr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) const union sctp_addr *laddr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) struct sctp_transport **transportp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) static struct sctp_endpoint *__sctp_rcv_lookup_endpoint(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) struct net *net, struct sk_buff *skb,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) const union sctp_addr *laddr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) const union sctp_addr *daddr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) static struct sctp_association *__sctp_lookup_association(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) struct net *net,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) const union sctp_addr *local,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) const union sctp_addr *peer,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) struct sctp_transport **pt);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) static int sctp_add_backlog(struct sock *sk, struct sk_buff *skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) /* Calculate the SCTP checksum of an SCTP packet. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) static inline int sctp_rcv_checksum(struct net *net, struct sk_buff *skb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) struct sctphdr *sh = sctp_hdr(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) __le32 cmp = sh->checksum;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) __le32 val = sctp_compute_cksum(skb, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) if (val != cmp) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) /* CRC failure, dump it. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) __SCTP_INC_STATS(net, SCTP_MIB_CHECKSUMERRORS);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) return -1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) * This is the routine which IP calls when receiving an SCTP packet.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) int sctp_rcv(struct sk_buff *skb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) struct sock *sk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) struct sctp_association *asoc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) struct sctp_endpoint *ep = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) struct sctp_ep_common *rcvr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) struct sctp_transport *transport = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) struct sctp_chunk *chunk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) union sctp_addr src;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) union sctp_addr dest;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) int family;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) struct sctp_af *af;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) struct net *net = dev_net(skb->dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) bool is_gso = skb_is_gso(skb) && skb_is_gso_sctp(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) if (skb->pkt_type != PACKET_HOST)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) goto discard_it;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) __SCTP_INC_STATS(net, SCTP_MIB_INSCTPPACKS);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) /* If packet is too small to contain a single chunk, let's not
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) * waste time on it anymore.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) if (skb->len < sizeof(struct sctphdr) + sizeof(struct sctp_chunkhdr) +
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) skb_transport_offset(skb))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) goto discard_it;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) /* If the packet is fragmented and we need to do crc checking,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) * it's better to just linearize it otherwise crc computing
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) * takes longer.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) if ((!is_gso && skb_linearize(skb)) ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) !pskb_may_pull(skb, sizeof(struct sctphdr)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) goto discard_it;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) /* Pull up the IP header. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) __skb_pull(skb, skb_transport_offset(skb));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) skb->csum_valid = 0; /* Previous value not applicable */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) if (skb_csum_unnecessary(skb))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) __skb_decr_checksum_unnecessary(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) else if (!sctp_checksum_disable &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) !is_gso &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) sctp_rcv_checksum(net, skb) < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) goto discard_it;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) skb->csum_valid = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) __skb_pull(skb, sizeof(struct sctphdr));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) family = ipver2af(ip_hdr(skb)->version);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) af = sctp_get_af_specific(family);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) if (unlikely(!af))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) goto discard_it;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) SCTP_INPUT_CB(skb)->af = af;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) /* Initialize local addresses for lookups. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) af->from_skb(&src, skb, 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) af->from_skb(&dest, skb, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) /* If the packet is to or from a non-unicast address,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) * silently discard the packet.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) * This is not clearly defined in the RFC except in section
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) * 8.4 - OOTB handling. However, based on the book "Stream Control
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) * Transmission Protocol" 2.1, "It is important to note that the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) * IP address of an SCTP transport address must be a routable
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) * unicast address. In other words, IP multicast addresses and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) * IP broadcast addresses cannot be used in an SCTP transport
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) * address."
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) if (!af->addr_valid(&src, NULL, skb) ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) !af->addr_valid(&dest, NULL, skb))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) goto discard_it;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) asoc = __sctp_rcv_lookup(net, skb, &src, &dest, &transport);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) if (!asoc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) ep = __sctp_rcv_lookup_endpoint(net, skb, &dest, &src);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) /* Retrieve the common input handling substructure. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) rcvr = asoc ? &asoc->base : &ep->base;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) sk = rcvr->sk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) * If a frame arrives on an interface and the receiving socket is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) * bound to another interface, via SO_BINDTODEVICE, treat it as OOTB
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) if (sk->sk_bound_dev_if && (sk->sk_bound_dev_if != af->skb_iif(skb))) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) if (transport) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) sctp_transport_put(transport);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) asoc = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) transport = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) sctp_endpoint_put(ep);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) ep = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) sk = net->sctp.ctl_sock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) ep = sctp_sk(sk)->ep;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) sctp_endpoint_hold(ep);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) rcvr = &ep->base;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) * RFC 2960, 8.4 - Handle "Out of the blue" Packets.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) * An SCTP packet is called an "out of the blue" (OOTB)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) * packet if it is correctly formed, i.e., passed the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) * receiver's checksum check, but the receiver is not
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) * able to identify the association to which this
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) * packet belongs.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) if (!asoc) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) if (sctp_rcv_ootb(skb)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) __SCTP_INC_STATS(net, SCTP_MIB_OUTOFBLUES);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) goto discard_release;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) if (!xfrm_policy_check(sk, XFRM_POLICY_IN, skb, family))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) goto discard_release;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) nf_reset_ct(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) if (sk_filter(sk, skb))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) goto discard_release;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) /* Create an SCTP packet structure. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) chunk = sctp_chunkify(skb, asoc, sk, GFP_ATOMIC);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) if (!chunk)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) goto discard_release;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) SCTP_INPUT_CB(skb)->chunk = chunk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) /* Remember what endpoint is to handle this packet. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) chunk->rcvr = rcvr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) /* Remember the SCTP header. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) chunk->sctp_hdr = sctp_hdr(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) /* Set the source and destination addresses of the incoming chunk. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) sctp_init_addrs(chunk, &src, &dest);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) /* Remember where we came from. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) chunk->transport = transport;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) /* Acquire access to the sock lock. Note: We are safe from other
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) * bottom halves on this lock, but a user may be in the lock too,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229) * so check if it is busy.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) bh_lock_sock(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) if (sk != rcvr->sk) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) /* Our cached sk is different from the rcvr->sk. This is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) * because migrate()/accept() may have moved the association
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) * to a new socket and released all the sockets. So now we
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) * are holding a lock on the old socket while the user may
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) * be doing something with the new socket. Switch our veiw
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) * of the current sk.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) bh_unlock_sock(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) sk = rcvr->sk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243) bh_lock_sock(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246) if (sock_owned_by_user(sk) || !sctp_newsk_ready(sk)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) if (sctp_add_backlog(sk, skb)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) bh_unlock_sock(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) sctp_chunk_free(chunk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250) skb = NULL; /* sctp_chunk_free already freed the skb */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) goto discard_release;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) __SCTP_INC_STATS(net, SCTP_MIB_IN_PKT_BACKLOG);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) __SCTP_INC_STATS(net, SCTP_MIB_IN_PKT_SOFTIRQ);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) sctp_inq_push(&chunk->rcvr->inqueue, chunk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259) bh_unlock_sock(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) /* Release the asoc/ep ref we took in the lookup calls. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) if (transport)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) sctp_transport_put(transport);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265) sctp_endpoint_put(ep);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) discard_it:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) __SCTP_INC_STATS(net, SCTP_MIB_IN_PKT_DISCARDS);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) kfree_skb(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) discard_release:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) /* Release the asoc/ep ref we took in the lookup calls. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276) if (transport)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277) sctp_transport_put(transport);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) sctp_endpoint_put(ep);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) goto discard_it;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) /* Process the backlog queue of the socket. Every skb on
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) * the backlog holds a ref on an association or endpoint.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) * We hold this ref throughout the state machine to make
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287) * sure that the structure we need is still around.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) int sctp_backlog_rcv(struct sock *sk, struct sk_buff *skb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291) struct sctp_chunk *chunk = SCTP_INPUT_CB(skb)->chunk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) struct sctp_inq *inqueue = &chunk->rcvr->inqueue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) struct sctp_transport *t = chunk->transport;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) struct sctp_ep_common *rcvr = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295) int backloged = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) rcvr = chunk->rcvr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299) /* If the rcvr is dead then the association or endpoint
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300) * has been deleted and we can safely drop the chunk
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301) * and refs that we are holding.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) if (rcvr->dead) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304) sctp_chunk_free(chunk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305) goto done;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308) if (unlikely(rcvr->sk != sk)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309) /* In this case, the association moved from one socket to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310) * another. We are currently sitting on the backlog of the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311) * old socket, so we need to move.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312) * However, since we are here in the process context we
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313) * need to take make sure that the user doesn't own
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314) * the new socket when we process the packet.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315) * If the new socket is user-owned, queue the chunk to the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316) * backlog of the new socket without dropping any refs.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) * Otherwise, we can safely push the chunk on the inqueue.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) sk = rcvr->sk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321) local_bh_disable();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322) bh_lock_sock(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324) if (sock_owned_by_user(sk) || !sctp_newsk_ready(sk)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325) if (sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326) sctp_chunk_free(chunk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328) backloged = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329) } else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330) sctp_inq_push(inqueue, chunk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332) bh_unlock_sock(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333) local_bh_enable();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335) /* If the chunk was backloged again, don't drop refs */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 336) if (backloged)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 337) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 338) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 339) if (!sctp_newsk_ready(sk)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 340) if (!sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 341) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 342) sctp_chunk_free(chunk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 343) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 344) sctp_inq_push(inqueue, chunk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 345) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 346) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 347)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 348) done:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 349) /* Release the refs we took in sctp_add_backlog */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 350) if (SCTP_EP_TYPE_ASSOCIATION == rcvr->type)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 351) sctp_transport_put(t);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 352) else if (SCTP_EP_TYPE_SOCKET == rcvr->type)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 353) sctp_endpoint_put(sctp_ep(rcvr));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 354) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 355) BUG();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 356)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 357) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 358) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 359)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 360) static int sctp_add_backlog(struct sock *sk, struct sk_buff *skb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 361) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 362) struct sctp_chunk *chunk = SCTP_INPUT_CB(skb)->chunk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 363) struct sctp_transport *t = chunk->transport;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 364) struct sctp_ep_common *rcvr = chunk->rcvr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 365) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 366)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 367) ret = sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 368) if (!ret) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 369) /* Hold the assoc/ep while hanging on the backlog queue.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 370) * This way, we know structures we need will not disappear
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 371) * from us
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 372) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 373) if (SCTP_EP_TYPE_ASSOCIATION == rcvr->type)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 374) sctp_transport_hold(t);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 375) else if (SCTP_EP_TYPE_SOCKET == rcvr->type)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 376) sctp_endpoint_hold(sctp_ep(rcvr));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 377) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 378) BUG();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 379) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 380) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 381)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 382) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 383)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 384) /* Handle icmp frag needed error. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 385) void sctp_icmp_frag_needed(struct sock *sk, struct sctp_association *asoc,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 386) struct sctp_transport *t, __u32 pmtu)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 387) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 388) if (!t || (t->pathmtu <= pmtu))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 389) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 390)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 391) if (sock_owned_by_user(sk)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 392) atomic_set(&t->mtu_info, pmtu);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 393) asoc->pmtu_pending = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 394) t->pmtu_pending = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 395) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 396) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 397)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 398) if (!(t->param_flags & SPP_PMTUD_ENABLE))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 399) /* We can't allow retransmitting in such case, as the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 400) * retransmission would be sized just as before, and thus we
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 401) * would get another icmp, and retransmit again.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 402) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 403) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 404)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 405) /* Update transports view of the MTU. Return if no update was needed.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 406) * If an update wasn't needed/possible, it also doesn't make sense to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 407) * try to retransmit now.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 408) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 409) if (!sctp_transport_update_pmtu(t, pmtu))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 410) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 411)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 412) /* Update association pmtu. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 413) sctp_assoc_sync_pmtu(asoc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 414)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 415) /* Retransmit with the new pmtu setting. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 416) sctp_retransmit(&asoc->outqueue, t, SCTP_RTXR_PMTUD);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 417) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 418)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 419) void sctp_icmp_redirect(struct sock *sk, struct sctp_transport *t,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 420) struct sk_buff *skb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 421) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 422) struct dst_entry *dst;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 423)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 424) if (sock_owned_by_user(sk) || !t)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 425) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 426) dst = sctp_transport_dst_check(t);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 427) if (dst)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 428) dst->ops->redirect(dst, sk, skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 429) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 430)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 431) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 432) * SCTP Implementer's Guide, 2.37 ICMP handling procedures
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 433) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 434) * ICMP8) If the ICMP code is a "Unrecognized next header type encountered"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 435) * or a "Protocol Unreachable" treat this message as an abort
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 436) * with the T bit set.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 437) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 438) * This function sends an event to the state machine, which will abort the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 439) * association.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 440) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 441) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 442) void sctp_icmp_proto_unreachable(struct sock *sk,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 443) struct sctp_association *asoc,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 444) struct sctp_transport *t)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 445) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 446) if (sock_owned_by_user(sk)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 447) if (timer_pending(&t->proto_unreach_timer))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 448) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 449) else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 450) if (!mod_timer(&t->proto_unreach_timer,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 451) jiffies + (HZ/20)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 452) sctp_transport_hold(t);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 453) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 454) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 455) struct net *net = sock_net(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 456)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 457) pr_debug("%s: unrecognized next header type "
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 458) "encountered!\n", __func__);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 459)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 460) if (del_timer(&t->proto_unreach_timer))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 461) sctp_transport_put(t);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 462)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 463) sctp_do_sm(net, SCTP_EVENT_T_OTHER,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 464) SCTP_ST_OTHER(SCTP_EVENT_ICMP_PROTO_UNREACH),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 465) asoc->state, asoc->ep, asoc, t,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 466) GFP_ATOMIC);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 467) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 468) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 469)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 470) /* Common lookup code for icmp/icmpv6 error handler. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 471) struct sock *sctp_err_lookup(struct net *net, int family, struct sk_buff *skb,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 472) struct sctphdr *sctphdr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 473) struct sctp_association **app,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 474) struct sctp_transport **tpp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 475) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 476) struct sctp_init_chunk *chunkhdr, _chunkhdr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 477) union sctp_addr saddr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 478) union sctp_addr daddr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 479) struct sctp_af *af;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 480) struct sock *sk = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 481) struct sctp_association *asoc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 482) struct sctp_transport *transport = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 483) __u32 vtag = ntohl(sctphdr->vtag);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 484)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 485) *app = NULL; *tpp = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 486)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 487) af = sctp_get_af_specific(family);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 488) if (unlikely(!af)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 489) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 490) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 491)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 492) /* Initialize local addresses for lookups. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 493) af->from_skb(&saddr, skb, 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 494) af->from_skb(&daddr, skb, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 495)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 496) /* Look for an association that matches the incoming ICMP error
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 497) * packet.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 498) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 499) asoc = __sctp_lookup_association(net, &saddr, &daddr, &transport);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 500) if (!asoc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 501) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 502)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 503) sk = asoc->base.sk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 504)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 505) /* RFC 4960, Appendix C. ICMP Handling
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 506) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 507) * ICMP6) An implementation MUST validate that the Verification Tag
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 508) * contained in the ICMP message matches the Verification Tag of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 509) * the peer. If the Verification Tag is not 0 and does NOT
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 510) * match, discard the ICMP message. If it is 0 and the ICMP
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 511) * message contains enough bytes to verify that the chunk type is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 512) * an INIT chunk and that the Initiate Tag matches the tag of the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 513) * peer, continue with ICMP7. If the ICMP message is too short
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 514) * or the chunk type or the Initiate Tag does not match, silently
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 515) * discard the packet.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 516) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 517) if (vtag == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 518) /* chunk header + first 4 octects of init header */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 519) chunkhdr = skb_header_pointer(skb, skb_transport_offset(skb) +
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 520) sizeof(struct sctphdr),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 521) sizeof(struct sctp_chunkhdr) +
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 522) sizeof(__be32), &_chunkhdr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 523) if (!chunkhdr ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 524) chunkhdr->chunk_hdr.type != SCTP_CID_INIT ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 525) ntohl(chunkhdr->init_hdr.init_tag) != asoc->c.my_vtag)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 526) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 527)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 528) } else if (vtag != asoc->c.peer_vtag) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 529) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 530) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 531)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 532) bh_lock_sock(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 533)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 534) /* If too many ICMPs get dropped on busy
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 535) * servers this needs to be solved differently.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 536) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 537) if (sock_owned_by_user(sk))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 538) __NET_INC_STATS(net, LINUX_MIB_LOCKDROPPEDICMPS);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 539)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 540) *app = asoc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 541) *tpp = transport;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 542) return sk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 543)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 544) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 545) sctp_transport_put(transport);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 546) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 547) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 548)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 549) /* Common cleanup code for icmp/icmpv6 error handler. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 550) void sctp_err_finish(struct sock *sk, struct sctp_transport *t)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 551) __releases(&((__sk)->sk_lock.slock))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 552) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 553) bh_unlock_sock(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 554) sctp_transport_put(t);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 555) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 556)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 557) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 558) * This routine is called by the ICMP module when it gets some
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 559) * sort of error condition. If err < 0 then the socket should
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 560) * be closed and the error returned to the user. If err > 0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 561) * it's just the icmp type << 8 | icmp code. After adjustment
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 562) * header points to the first 8 bytes of the sctp header. We need
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 563) * to find the appropriate port.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 564) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 565) * The locking strategy used here is very "optimistic". When
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 566) * someone else accesses the socket the ICMP is just dropped
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 567) * and for some paths there is no check at all.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 568) * A more general error queue to queue errors for later handling
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 569) * is probably better.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 570) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 571) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 572) int sctp_v4_err(struct sk_buff *skb, __u32 info)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 573) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 574) const struct iphdr *iph = (const struct iphdr *)skb->data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 575) const int ihlen = iph->ihl * 4;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 576) const int type = icmp_hdr(skb)->type;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 577) const int code = icmp_hdr(skb)->code;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 578) struct sock *sk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 579) struct sctp_association *asoc = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 580) struct sctp_transport *transport;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 581) struct inet_sock *inet;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 582) __u16 saveip, savesctp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 583) int err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 584) struct net *net = dev_net(skb->dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 585)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 586) /* Fix up skb to look at the embedded net header. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 587) saveip = skb->network_header;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 588) savesctp = skb->transport_header;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 589) skb_reset_network_header(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 590) skb_set_transport_header(skb, ihlen);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 591) sk = sctp_err_lookup(net, AF_INET, skb, sctp_hdr(skb), &asoc, &transport);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 592) /* Put back, the original values. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 593) skb->network_header = saveip;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 594) skb->transport_header = savesctp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 595) if (!sk) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 596) __ICMP_INC_STATS(net, ICMP_MIB_INERRORS);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 597) return -ENOENT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 598) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 599) /* Warning: The sock lock is held. Remember to call
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 600) * sctp_err_finish!
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 601) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 602)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 603) switch (type) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 604) case ICMP_PARAMETERPROB:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 605) err = EPROTO;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 606) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 607) case ICMP_DEST_UNREACH:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 608) if (code > NR_ICMP_UNREACH)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 609) goto out_unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 610)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 611) /* PMTU discovery (RFC1191) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 612) if (ICMP_FRAG_NEEDED == code) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 613) sctp_icmp_frag_needed(sk, asoc, transport,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 614) SCTP_TRUNC4(info));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 615) goto out_unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 616) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 617) if (ICMP_PROT_UNREACH == code) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 618) sctp_icmp_proto_unreachable(sk, asoc,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 619) transport);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 620) goto out_unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 621) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 622) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 623) err = icmp_err_convert[code].errno;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 624) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 625) case ICMP_TIME_EXCEEDED:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 626) /* Ignore any time exceeded errors due to fragment reassembly
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 627) * timeouts.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 628) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 629) if (ICMP_EXC_FRAGTIME == code)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 630) goto out_unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 631)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 632) err = EHOSTUNREACH;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 633) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 634) case ICMP_REDIRECT:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 635) sctp_icmp_redirect(sk, transport, skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 636) /* Fall through to out_unlock. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 637) default:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 638) goto out_unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 639) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 640)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 641) inet = inet_sk(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 642) if (!sock_owned_by_user(sk) && inet->recverr) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 643) sk->sk_err = err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 644) sk->sk_error_report(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 645) } else { /* Only an error on timeout */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 646) sk->sk_err_soft = err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 647) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 648)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 649) out_unlock:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 650) sctp_err_finish(sk, transport);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 651) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 652) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 653)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 654) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 655) * RFC 2960, 8.4 - Handle "Out of the blue" Packets.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 656) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 657) * This function scans all the chunks in the OOTB packet to determine if
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 658) * the packet should be discarded right away. If a response might be needed
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 659) * for this packet, or, if further processing is possible, the packet will
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 660) * be queued to a proper inqueue for the next phase of handling.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 661) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 662) * Output:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 663) * Return 0 - If further processing is needed.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 664) * Return 1 - If the packet can be discarded right away.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 665) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 666) static int sctp_rcv_ootb(struct sk_buff *skb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 667) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 668) struct sctp_chunkhdr *ch, _ch;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 669) int ch_end, offset = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 670)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 671) /* Scan through all the chunks in the packet. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 672) do {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 673) /* Make sure we have at least the header there */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 674) if (offset + sizeof(_ch) > skb->len)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 675) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 676)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 677) ch = skb_header_pointer(skb, offset, sizeof(*ch), &_ch);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 678)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 679) /* Break out if chunk length is less then minimal. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 680) if (!ch || ntohs(ch->length) < sizeof(_ch))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 681) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 682)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 683) ch_end = offset + SCTP_PAD4(ntohs(ch->length));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 684) if (ch_end > skb->len)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 685) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 686)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 687) /* RFC 8.4, 2) If the OOTB packet contains an ABORT chunk, the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 688) * receiver MUST silently discard the OOTB packet and take no
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 689) * further action.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 690) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 691) if (SCTP_CID_ABORT == ch->type)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 692) goto discard;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 693)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 694) /* RFC 8.4, 6) If the packet contains a SHUTDOWN COMPLETE
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 695) * chunk, the receiver should silently discard the packet
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 696) * and take no further action.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 697) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 698) if (SCTP_CID_SHUTDOWN_COMPLETE == ch->type)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 699) goto discard;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 700)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 701) /* RFC 4460, 2.11.2
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 702) * This will discard packets with INIT chunk bundled as
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 703) * subsequent chunks in the packet. When INIT is first,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 704) * the normal INIT processing will discard the chunk.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 705) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 706) if (SCTP_CID_INIT == ch->type && (void *)ch != skb->data)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 707) goto discard;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 708)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 709) offset = ch_end;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 710) } while (ch_end < skb->len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 711)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 712) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 713)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 714) discard:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 715) return 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 716) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 717)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 718) /* Insert endpoint into the hash table. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 719) static int __sctp_hash_endpoint(struct sctp_endpoint *ep)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 720) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 721) struct sock *sk = ep->base.sk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 722) struct net *net = sock_net(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 723) struct sctp_hashbucket *head;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 724) struct sctp_ep_common *epb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 725)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 726) epb = &ep->base;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 727) epb->hashent = sctp_ep_hashfn(net, epb->bind_addr.port);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 728) head = &sctp_ep_hashtable[epb->hashent];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 729)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 730) if (sk->sk_reuseport) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 731) bool any = sctp_is_ep_boundall(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 732) struct sctp_ep_common *epb2;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 733) struct list_head *list;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 734) int cnt = 0, err = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 735)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 736) list_for_each(list, &ep->base.bind_addr.address_list)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 737) cnt++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 738)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 739) sctp_for_each_hentry(epb2, &head->chain) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 740) struct sock *sk2 = epb2->sk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 741)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 742) if (!net_eq(sock_net(sk2), net) || sk2 == sk ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 743) !uid_eq(sock_i_uid(sk2), sock_i_uid(sk)) ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 744) !sk2->sk_reuseport)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 745) continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 746)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 747) err = sctp_bind_addrs_check(sctp_sk(sk2),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 748) sctp_sk(sk), cnt);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 749) if (!err) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 750) err = reuseport_add_sock(sk, sk2, any);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 751) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 752) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 753) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 754) } else if (err < 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 755) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 756) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 757) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 758)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 759) if (err) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 760) err = reuseport_alloc(sk, any);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 761) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 762) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 763) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 764) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 765)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 766) write_lock(&head->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 767) hlist_add_head(&epb->node, &head->chain);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 768) write_unlock(&head->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 769) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 770) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 771)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 772) /* Add an endpoint to the hash. Local BH-safe. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 773) int sctp_hash_endpoint(struct sctp_endpoint *ep)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 774) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 775) int err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 776)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 777) local_bh_disable();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 778) err = __sctp_hash_endpoint(ep);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 779) local_bh_enable();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 780)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 781) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 782) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 783)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 784) /* Remove endpoint from the hash table. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 785) static void __sctp_unhash_endpoint(struct sctp_endpoint *ep)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 786) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 787) struct sock *sk = ep->base.sk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 788) struct sctp_hashbucket *head;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 789) struct sctp_ep_common *epb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 790)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 791) epb = &ep->base;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 792)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 793) epb->hashent = sctp_ep_hashfn(sock_net(sk), epb->bind_addr.port);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 794)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 795) head = &sctp_ep_hashtable[epb->hashent];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 796)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 797) if (rcu_access_pointer(sk->sk_reuseport_cb))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 798) reuseport_detach_sock(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 799)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 800) write_lock(&head->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 801) hlist_del_init(&epb->node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 802) write_unlock(&head->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 803) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 804)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 805) /* Remove endpoint from the hash. Local BH-safe. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 806) void sctp_unhash_endpoint(struct sctp_endpoint *ep)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 807) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 808) local_bh_disable();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 809) __sctp_unhash_endpoint(ep);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 810) local_bh_enable();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 811) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 812)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 813) static inline __u32 sctp_hashfn(const struct net *net, __be16 lport,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 814) const union sctp_addr *paddr, __u32 seed)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 815) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 816) __u32 addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 817)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 818) if (paddr->sa.sa_family == AF_INET6)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 819) addr = jhash(&paddr->v6.sin6_addr, 16, seed);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 820) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 821) addr = (__force __u32)paddr->v4.sin_addr.s_addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 822)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 823) return jhash_3words(addr, ((__force __u32)paddr->v4.sin_port) << 16 |
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 824) (__force __u32)lport, net_hash_mix(net), seed);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 825) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 826)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 827) /* Look up an endpoint. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 828) static struct sctp_endpoint *__sctp_rcv_lookup_endpoint(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 829) struct net *net, struct sk_buff *skb,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 830) const union sctp_addr *laddr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 831) const union sctp_addr *paddr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 832) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 833) struct sctp_hashbucket *head;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 834) struct sctp_ep_common *epb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 835) struct sctp_endpoint *ep;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 836) struct sock *sk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 837) __be16 lport;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 838) int hash;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 839)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 840) lport = laddr->v4.sin_port;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 841) hash = sctp_ep_hashfn(net, ntohs(lport));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 842) head = &sctp_ep_hashtable[hash];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 843) read_lock(&head->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 844) sctp_for_each_hentry(epb, &head->chain) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 845) ep = sctp_ep(epb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 846) if (sctp_endpoint_is_match(ep, net, laddr))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 847) goto hit;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 848) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 849)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 850) ep = sctp_sk(net->sctp.ctl_sock)->ep;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 851)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 852) hit:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 853) sk = ep->base.sk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 854) if (sk->sk_reuseport) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 855) __u32 phash = sctp_hashfn(net, lport, paddr, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 856)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 857) sk = reuseport_select_sock(sk, phash, skb,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 858) sizeof(struct sctphdr));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 859) if (sk)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 860) ep = sctp_sk(sk)->ep;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 861) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 862) sctp_endpoint_hold(ep);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 863) read_unlock(&head->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 864) return ep;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 865) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 866)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 867) /* rhashtable for transport */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 868) struct sctp_hash_cmp_arg {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 869) const union sctp_addr *paddr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 870) const struct net *net;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 871) __be16 lport;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 872) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 873)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 874) static inline int sctp_hash_cmp(struct rhashtable_compare_arg *arg,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 875) const void *ptr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 876) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 877) struct sctp_transport *t = (struct sctp_transport *)ptr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 878) const struct sctp_hash_cmp_arg *x = arg->key;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 879) int err = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 880)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 881) if (!sctp_cmp_addr_exact(&t->ipaddr, x->paddr))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 882) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 883) if (!sctp_transport_hold(t))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 884) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 885)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 886) if (!net_eq(t->asoc->base.net, x->net))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 887) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 888) if (x->lport != htons(t->asoc->base.bind_addr.port))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 889) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 890)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 891) err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 892) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 893) sctp_transport_put(t);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 894) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 895) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 896)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 897) static inline __u32 sctp_hash_obj(const void *data, u32 len, u32 seed)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 898) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 899) const struct sctp_transport *t = data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 900)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 901) return sctp_hashfn(t->asoc->base.net,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 902) htons(t->asoc->base.bind_addr.port),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 903) &t->ipaddr, seed);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 904) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 905)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 906) static inline __u32 sctp_hash_key(const void *data, u32 len, u32 seed)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 907) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 908) const struct sctp_hash_cmp_arg *x = data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 909)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 910) return sctp_hashfn(x->net, x->lport, x->paddr, seed);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 911) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 912)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 913) static const struct rhashtable_params sctp_hash_params = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 914) .head_offset = offsetof(struct sctp_transport, node),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 915) .hashfn = sctp_hash_key,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 916) .obj_hashfn = sctp_hash_obj,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 917) .obj_cmpfn = sctp_hash_cmp,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 918) .automatic_shrinking = true,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 919) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 920)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 921) int sctp_transport_hashtable_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 922) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 923) return rhltable_init(&sctp_transport_hashtable, &sctp_hash_params);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 924) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 925)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 926) void sctp_transport_hashtable_destroy(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 927) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 928) rhltable_destroy(&sctp_transport_hashtable);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 929) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 930)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 931) int sctp_hash_transport(struct sctp_transport *t)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 932) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 933) struct sctp_transport *transport;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 934) struct rhlist_head *tmp, *list;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 935) struct sctp_hash_cmp_arg arg;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 936) int err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 937)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 938) if (t->asoc->temp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 939) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 940)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 941) arg.net = t->asoc->base.net;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 942) arg.paddr = &t->ipaddr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 943) arg.lport = htons(t->asoc->base.bind_addr.port);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 944)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 945) rcu_read_lock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 946) list = rhltable_lookup(&sctp_transport_hashtable, &arg,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 947) sctp_hash_params);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 948)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 949) rhl_for_each_entry_rcu(transport, tmp, list, node)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 950) if (transport->asoc->ep == t->asoc->ep) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 951) rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 952) return -EEXIST;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 953) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 954) rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 955)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 956) err = rhltable_insert_key(&sctp_transport_hashtable, &arg,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 957) &t->node, sctp_hash_params);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 958) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 959) pr_err_once("insert transport fail, errno %d\n", err);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 960)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 961) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 962) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 963)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 964) void sctp_unhash_transport(struct sctp_transport *t)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 965) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 966) if (t->asoc->temp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 967) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 968)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 969) rhltable_remove(&sctp_transport_hashtable, &t->node,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 970) sctp_hash_params);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 971) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 972)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 973) /* return a transport with holding it */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 974) struct sctp_transport *sctp_addrs_lookup_transport(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 975) struct net *net,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 976) const union sctp_addr *laddr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 977) const union sctp_addr *paddr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 978) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 979) struct rhlist_head *tmp, *list;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 980) struct sctp_transport *t;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 981) struct sctp_hash_cmp_arg arg = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 982) .paddr = paddr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 983) .net = net,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 984) .lport = laddr->v4.sin_port,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 985) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 986)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 987) list = rhltable_lookup(&sctp_transport_hashtable, &arg,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 988) sctp_hash_params);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 989)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 990) rhl_for_each_entry_rcu(t, tmp, list, node) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 991) if (!sctp_transport_hold(t))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 992) continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 993)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 994) if (sctp_bind_addr_match(&t->asoc->base.bind_addr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 995) laddr, sctp_sk(t->asoc->base.sk)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 996) return t;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 997) sctp_transport_put(t);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 998) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 999)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1000) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1001) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1002)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1003) /* return a transport without holding it, as it's only used under sock lock */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1004) struct sctp_transport *sctp_epaddr_lookup_transport(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1005) const struct sctp_endpoint *ep,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1006) const union sctp_addr *paddr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1007) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1008) struct rhlist_head *tmp, *list;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1009) struct sctp_transport *t;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1010) struct sctp_hash_cmp_arg arg = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1011) .paddr = paddr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1012) .net = ep->base.net,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1013) .lport = htons(ep->base.bind_addr.port),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1014) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1015)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1016) list = rhltable_lookup(&sctp_transport_hashtable, &arg,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1017) sctp_hash_params);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1018)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1019) rhl_for_each_entry_rcu(t, tmp, list, node)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1020) if (ep == t->asoc->ep)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1021) return t;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1022)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1023) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1024) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1025)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1026) /* Look up an association. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1027) static struct sctp_association *__sctp_lookup_association(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1028) struct net *net,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1029) const union sctp_addr *local,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1030) const union sctp_addr *peer,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1031) struct sctp_transport **pt)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1032) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1033) struct sctp_transport *t;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1034) struct sctp_association *asoc = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1035)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1036) t = sctp_addrs_lookup_transport(net, local, peer);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1037) if (!t)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1038) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1039)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1040) asoc = t->asoc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1041) *pt = t;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1042)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1043) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1044) return asoc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1045) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1046)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1047) /* Look up an association. protected by RCU read lock */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1048) static
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1049) struct sctp_association *sctp_lookup_association(struct net *net,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1050) const union sctp_addr *laddr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1051) const union sctp_addr *paddr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1052) struct sctp_transport **transportp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1053) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1054) struct sctp_association *asoc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1055)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1056) rcu_read_lock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1057) asoc = __sctp_lookup_association(net, laddr, paddr, transportp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1058) rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1059)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1060) return asoc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1061) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1062)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1063) /* Is there an association matching the given local and peer addresses? */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1064) bool sctp_has_association(struct net *net,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1065) const union sctp_addr *laddr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1066) const union sctp_addr *paddr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1067) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1068) struct sctp_transport *transport;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1069)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1070) if (sctp_lookup_association(net, laddr, paddr, &transport)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1071) sctp_transport_put(transport);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1072) return true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1073) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1074)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1075) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1076) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1077)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1078) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1079) * SCTP Implementors Guide, 2.18 Handling of address
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1080) * parameters within the INIT or INIT-ACK.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1081) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1082) * D) When searching for a matching TCB upon reception of an INIT
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1083) * or INIT-ACK chunk the receiver SHOULD use not only the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1084) * source address of the packet (containing the INIT or
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1085) * INIT-ACK) but the receiver SHOULD also use all valid
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1086) * address parameters contained within the chunk.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1087) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1088) * 2.18.3 Solution description
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1089) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1090) * This new text clearly specifies to an implementor the need
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1091) * to look within the INIT or INIT-ACK. Any implementation that
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1092) * does not do this, may not be able to establish associations
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1093) * in certain circumstances.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1094) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1095) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1096) static struct sctp_association *__sctp_rcv_init_lookup(struct net *net,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1097) struct sk_buff *skb,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1098) const union sctp_addr *laddr, struct sctp_transport **transportp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1099) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1100) struct sctp_association *asoc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1101) union sctp_addr addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1102) union sctp_addr *paddr = &addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1103) struct sctphdr *sh = sctp_hdr(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1104) union sctp_params params;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1105) struct sctp_init_chunk *init;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1106) struct sctp_af *af;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1107)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1108) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1109) * This code will NOT touch anything inside the chunk--it is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1110) * strictly READ-ONLY.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1111) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1112) * RFC 2960 3 SCTP packet Format
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1113) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1114) * Multiple chunks can be bundled into one SCTP packet up to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1115) * the MTU size, except for the INIT, INIT ACK, and SHUTDOWN
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1116) * COMPLETE chunks. These chunks MUST NOT be bundled with any
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1117) * other chunk in a packet. See Section 6.10 for more details
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1118) * on chunk bundling.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1119) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1120)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1121) /* Find the start of the TLVs and the end of the chunk. This is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1122) * the region we search for address parameters.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1123) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1124) init = (struct sctp_init_chunk *)skb->data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1125)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1126) /* Walk the parameters looking for embedded addresses. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1127) sctp_walk_params(params, init, init_hdr.params) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1128)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1129) /* Note: Ignoring hostname addresses. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1130) af = sctp_get_af_specific(param_type2af(params.p->type));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1131) if (!af)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1132) continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1133)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1134) if (!af->from_addr_param(paddr, params.addr, sh->source, 0))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1135) continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1136)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1137) asoc = __sctp_lookup_association(net, laddr, paddr, transportp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1138) if (asoc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1139) return asoc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1140) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1141)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1142) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1143) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1144)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1145) /* ADD-IP, Section 5.2
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1146) * When an endpoint receives an ASCONF Chunk from the remote peer
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1147) * special procedures may be needed to identify the association the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1148) * ASCONF Chunk is associated with. To properly find the association
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1149) * the following procedures SHOULD be followed:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1150) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1151) * D2) If the association is not found, use the address found in the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1152) * Address Parameter TLV combined with the port number found in the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1153) * SCTP common header. If found proceed to rule D4.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1154) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1155) * D2-ext) If more than one ASCONF Chunks are packed together, use the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1156) * address found in the ASCONF Address Parameter TLV of each of the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1157) * subsequent ASCONF Chunks. If found, proceed to rule D4.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1158) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1159) static struct sctp_association *__sctp_rcv_asconf_lookup(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1160) struct net *net,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1161) struct sctp_chunkhdr *ch,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1162) const union sctp_addr *laddr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1163) __be16 peer_port,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1164) struct sctp_transport **transportp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1165) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1166) struct sctp_addip_chunk *asconf = (struct sctp_addip_chunk *)ch;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1167) struct sctp_af *af;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1168) union sctp_addr_param *param;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1169) union sctp_addr paddr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1170)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1171) if (ntohs(ch->length) < sizeof(*asconf) + sizeof(struct sctp_paramhdr))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1172) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1173)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1174) /* Skip over the ADDIP header and find the Address parameter */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1175) param = (union sctp_addr_param *)(asconf + 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1176)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1177) af = sctp_get_af_specific(param_type2af(param->p.type));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1178) if (unlikely(!af))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1179) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1180)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1181) if (!af->from_addr_param(&paddr, param, peer_port, 0))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1182) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1183)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1184) return __sctp_lookup_association(net, laddr, &paddr, transportp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1185) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1186)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1187)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1188) /* SCTP-AUTH, Section 6.3:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1189) * If the receiver does not find a STCB for a packet containing an AUTH
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1190) * chunk as the first chunk and not a COOKIE-ECHO chunk as the second
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1191) * chunk, it MUST use the chunks after the AUTH chunk to look up an existing
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1192) * association.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1193) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1194) * This means that any chunks that can help us identify the association need
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1195) * to be looked at to find this association.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1196) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1197) static struct sctp_association *__sctp_rcv_walk_lookup(struct net *net,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1198) struct sk_buff *skb,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1199) const union sctp_addr *laddr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1200) struct sctp_transport **transportp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1201) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1202) struct sctp_association *asoc = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1203) struct sctp_chunkhdr *ch;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1204) int have_auth = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1205) unsigned int chunk_num = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1206) __u8 *ch_end;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1207)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1208) /* Walk through the chunks looking for AUTH or ASCONF chunks
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1209) * to help us find the association.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1210) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1211) ch = (struct sctp_chunkhdr *)skb->data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1212) do {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1213) /* Break out if chunk length is less then minimal. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1214) if (ntohs(ch->length) < sizeof(*ch))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1215) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1216)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1217) ch_end = ((__u8 *)ch) + SCTP_PAD4(ntohs(ch->length));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1218) if (ch_end > skb_tail_pointer(skb))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1219) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1220)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1221) switch (ch->type) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1222) case SCTP_CID_AUTH:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1223) have_auth = chunk_num;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1224) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1225)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1226) case SCTP_CID_COOKIE_ECHO:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1227) /* If a packet arrives containing an AUTH chunk as
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1228) * a first chunk, a COOKIE-ECHO chunk as the second
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1229) * chunk, and possibly more chunks after them, and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1230) * the receiver does not have an STCB for that
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1231) * packet, then authentication is based on
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1232) * the contents of the COOKIE- ECHO chunk.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1233) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1234) if (have_auth == 1 && chunk_num == 2)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1235) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1236) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1237)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1238) case SCTP_CID_ASCONF:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1239) if (have_auth || net->sctp.addip_noauth)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1240) asoc = __sctp_rcv_asconf_lookup(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1241) net, ch, laddr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1242) sctp_hdr(skb)->source,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1243) transportp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1244) default:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1245) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1246) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1247)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1248) if (asoc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1249) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1250)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1251) ch = (struct sctp_chunkhdr *)ch_end;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1252) chunk_num++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1253) } while (ch_end + sizeof(*ch) < skb_tail_pointer(skb));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1254)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1255) return asoc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1256) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1257)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1258) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1259) * There are circumstances when we need to look inside the SCTP packet
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1260) * for information to help us find the association. Examples
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1261) * include looking inside of INIT/INIT-ACK chunks or after the AUTH
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1262) * chunks.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1263) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1264) static struct sctp_association *__sctp_rcv_lookup_harder(struct net *net,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1265) struct sk_buff *skb,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1266) const union sctp_addr *laddr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1267) struct sctp_transport **transportp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1268) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1269) struct sctp_chunkhdr *ch;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1270)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1271) /* We do not allow GSO frames here as we need to linearize and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1272) * then cannot guarantee frame boundaries. This shouldn't be an
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1273) * issue as packets hitting this are mostly INIT or INIT-ACK and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1274) * those cannot be on GSO-style anyway.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1275) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1276) if (skb_is_gso(skb) && skb_is_gso_sctp(skb))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1277) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1278)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1279) ch = (struct sctp_chunkhdr *)skb->data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1280)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1281) /* The code below will attempt to walk the chunk and extract
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1282) * parameter information. Before we do that, we need to verify
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1283) * that the chunk length doesn't cause overflow. Otherwise, we'll
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1284) * walk off the end.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1285) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1286) if (SCTP_PAD4(ntohs(ch->length)) > skb->len)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1287) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1288)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1289) /* If this is INIT/INIT-ACK look inside the chunk too. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1290) if (ch->type == SCTP_CID_INIT || ch->type == SCTP_CID_INIT_ACK)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1291) return __sctp_rcv_init_lookup(net, skb, laddr, transportp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1292)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1293) return __sctp_rcv_walk_lookup(net, skb, laddr, transportp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1294) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1295)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1296) /* Lookup an association for an inbound skb. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1297) static struct sctp_association *__sctp_rcv_lookup(struct net *net,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1298) struct sk_buff *skb,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1299) const union sctp_addr *paddr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1300) const union sctp_addr *laddr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1301) struct sctp_transport **transportp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1302) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1303) struct sctp_association *asoc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1304)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1305) asoc = __sctp_lookup_association(net, laddr, paddr, transportp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1306) if (asoc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1307) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1308)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1309) /* Further lookup for INIT/INIT-ACK packets.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1310) * SCTP Implementors Guide, 2.18 Handling of address
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1311) * parameters within the INIT or INIT-ACK.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1312) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1313) asoc = __sctp_rcv_lookup_harder(net, skb, laddr, transportp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1314) if (asoc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1315) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1316)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1317) if (paddr->sa.sa_family == AF_INET)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1318) pr_debug("sctp: asoc not found for src:%pI4:%d dst:%pI4:%d\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1319) &laddr->v4.sin_addr, ntohs(laddr->v4.sin_port),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1320) &paddr->v4.sin_addr, ntohs(paddr->v4.sin_port));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1321) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1322) pr_debug("sctp: asoc not found for src:%pI6:%d dst:%pI6:%d\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1323) &laddr->v6.sin6_addr, ntohs(laddr->v6.sin6_port),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1324) &paddr->v6.sin6_addr, ntohs(paddr->v6.sin6_port));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1325)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1326) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1327) return asoc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1328) }
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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