cregit-Linux how code gets into the kernel

Release 4.8 net/sctp/input.c

Directory: net/sctp
/* SCTP kernel implementation
 * Copyright (c) 1999-2000 Cisco, Inc.
 * Copyright (c) 1999-2001 Motorola, Inc.
 * Copyright (c) 2001-2003 International Business Machines, Corp.
 * Copyright (c) 2001 Intel Corp.
 * Copyright (c) 2001 Nokia, Inc.
 * Copyright (c) 2001 La Monte H.P. Yarroll
 *
 * This file is part of the SCTP kernel implementation
 *
 * These functions handle all input from the IP layer into SCTP.
 *
 * This SCTP implementation is free software;
 * you can redistribute it and/or modify it under the terms of
 * the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * This SCTP implementation is distributed in the hope that it
 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
 *                 ************************
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with GNU CC; see the file COPYING.  If not, see
 * <http://www.gnu.org/licenses/>.
 *
 * Please send any bug reports or fixes you make to the
 * email address(es):
 *    lksctp developers <linux-sctp@vger.kernel.org>
 *
 * Written or modified by:
 *    La Monte H.P. Yarroll <piggy@acm.org>
 *    Karl Knutson <karl@athena.chicago.il.us>
 *    Xingang Guo <xingang.guo@intel.com>
 *    Jon Grimm <jgrimm@us.ibm.com>
 *    Hui Huang <hui.huang@nokia.com>
 *    Daisy Chang <daisyc@us.ibm.com>
 *    Sridhar Samudrala <sri@us.ibm.com>
 *    Ardelle Fan <ardelle.fan@intel.com>
 */

#include <linux/types.h>
#include <linux/list.h> /* For struct list_head */
#include <linux/socket.h>
#include <linux/ip.h>
#include <linux/time.h> /* For struct timeval */
#include <linux/slab.h>
#include <net/ip.h>
#include <net/icmp.h>
#include <net/snmp.h>
#include <net/sock.h>
#include <net/xfrm.h>
#include <net/sctp/sctp.h>
#include <net/sctp/sm.h>
#include <net/sctp/checksum.h>
#include <net/net_namespace.h>

/* Forward declarations for internal helpers. */
static int sctp_rcv_ootb(struct sk_buff *);
static struct sctp_association *__sctp_rcv_lookup(struct net *net,
				      struct sk_buff *skb,
				      const union sctp_addr *paddr,
				      const union sctp_addr *laddr,
				      struct sctp_transport **transportp);
static struct sctp_endpoint *__sctp_rcv_lookup_endpoint(struct net *net,
						const union sctp_addr *laddr);
static struct sctp_association *__sctp_lookup_association(
					struct net *net,
					const union sctp_addr *local,
					const union sctp_addr *peer,
					struct sctp_transport **pt);

static int sctp_add_backlog(struct sock *sk, struct sk_buff *skb);


/* Calculate the SCTP checksum of an SCTP packet.  */

static inline int sctp_rcv_checksum(struct net *net, struct sk_buff *skb) { struct sctphdr *sh = sctp_hdr(skb); __le32 cmp = sh->checksum; __le32 val = sctp_compute_cksum(skb, 0); if (val != cmp) { /* CRC failure, dump it. */ __SCTP_INC_STATS(net, SCTP_MIB_CHECKSUMERRORS); return -1; } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
david s. millerdavid s. miller3856.72%111.11%
arnaldo carvalho de meloarnaldo carvalho de melo1014.93%111.11%
eric w. biedermaneric w. biederman710.45%111.11%
sridhar samudralasridhar samudrala57.46%222.22%
joe stringerjoe stringer34.48%111.11%
vladislav yasevichvladislav yasevich22.99%111.11%
hideaki yoshifujihideaki yoshifuji11.49%111.11%
eric dumazeteric dumazet11.49%111.11%
Total67100.00%9100.00%

/* * This is the routine which IP calls when receiving an SCTP packet. */
int sctp_rcv(struct sk_buff *skb) { struct sock *sk; struct sctp_association *asoc; struct sctp_endpoint *ep = NULL; struct sctp_ep_common *rcvr; struct sctp_transport *transport = NULL; struct sctp_chunk *chunk; union sctp_addr src; union sctp_addr dest; int family; struct sctp_af *af; struct net *net = dev_net(skb->dev); if (skb->pkt_type != PACKET_HOST) goto discard_it; __SCTP_INC_STATS(net, SCTP_MIB_INSCTPPACKS); /* If packet is too small to contain a single chunk, let's not * waste time on it anymore. */ if (skb->len < sizeof(struct sctphdr) + sizeof(struct sctp_chunkhdr) + skb_transport_offset(skb)) goto discard_it; /* If the packet is fragmented and we need to do crc checking, * it's better to just linearize it otherwise crc computing * takes longer. */ if ((!(skb_shinfo(skb)->gso_type & SKB_GSO_SCTP) && skb_linearize(skb)) || !pskb_may_pull(skb, sizeof(struct sctphdr))) goto discard_it; /* Pull up the IP header. */ __skb_pull(skb, skb_transport_offset(skb)); skb->csum_valid = 0; /* Previous value not applicable */ if (skb_csum_unnecessary(skb)) __skb_decr_checksum_unnecessary(skb); else if (!sctp_checksum_disable && !(skb_shinfo(skb)->gso_type & SKB_GSO_SCTP) && sctp_rcv_checksum(net, skb) < 0) goto discard_it; skb->csum_valid = 1; __skb_pull(skb, sizeof(struct sctphdr)); family = ipver2af(ip_hdr(skb)->version); af = sctp_get_af_specific(family); if (unlikely(!af)) goto discard_it; SCTP_INPUT_CB(skb)->af = af; /* Initialize local addresses for lookups. */ af->from_skb(&src, skb, 1); af->from_skb(&dest, skb, 0); /* If the packet is to or from a non-unicast address, * silently discard the packet. * * This is not clearly defined in the RFC except in section * 8.4 - OOTB handling. However, based on the book "Stream Control * Transmission Protocol" 2.1, "It is important to note that the * IP address of an SCTP transport address must be a routable * unicast address. In other words, IP multicast addresses and * IP broadcast addresses cannot be used in an SCTP transport * address." */ if (!af->addr_valid(&src, NULL, skb) || !af->addr_valid(&dest, NULL, skb)) goto discard_it; asoc = __sctp_rcv_lookup(net, skb, &src, &dest, &transport); if (!asoc) ep = __sctp_rcv_lookup_endpoint(net, &dest); /* Retrieve the common input handling substructure. */ rcvr = asoc ? &asoc->base : &ep->base; sk = rcvr->sk; /* * If a frame arrives on an interface and the receiving socket is * bound to another interface, via SO_BINDTODEVICE, treat it as OOTB */ if (sk->sk_bound_dev_if && (sk->sk_bound_dev_if != af->skb_iif(skb))) { if (asoc) { sctp_association_put(asoc); asoc = NULL; } else { sctp_endpoint_put(ep); ep = NULL; } sk = net->sctp.ctl_sock; ep = sctp_sk(sk)->ep; sctp_endpoint_hold(ep); rcvr = &ep->base; } /* * RFC 2960, 8.4 - Handle "Out of the blue" Packets. * An SCTP packet is called an "out of the blue" (OOTB) * packet if it is correctly formed, i.e., passed the * receiver's checksum check, but the receiver is not * able to identify the association to which this * packet belongs. */ if (!asoc) { if (sctp_rcv_ootb(skb)) { __SCTP_INC_STATS(net, SCTP_MIB_OUTOFBLUES); goto discard_release; } } if (!xfrm_policy_check(sk, XFRM_POLICY_IN, skb, family)) goto discard_release; nf_reset(skb); if (sk_filter(sk, skb)) goto discard_release; /* Create an SCTP packet structure. */ chunk = sctp_chunkify(skb, asoc, sk, GFP_ATOMIC); if (!chunk) goto discard_release; SCTP_INPUT_CB(skb)->chunk = chunk; /* Remember what endpoint is to handle this packet. */ chunk->rcvr = rcvr; /* Remember the SCTP header. */ chunk->sctp_hdr = sctp_hdr(skb); /* Set the source and destination addresses of the incoming chunk. */ sctp_init_addrs(chunk, &src, &dest); /* Remember where we came from. */ chunk->transport = transport; /* Acquire access to the sock lock. Note: We are safe from other * bottom halves on this lock, but a user may be in the lock too, * so check if it is busy. */ bh_lock_sock(sk); if (sk != rcvr->sk) { /* Our cached sk is different from the rcvr->sk. This is * because migrate()/accept() may have moved the association * to a new socket and released all the sockets. So now we * are holding a lock on the old socket while the user may * be doing something with the new socket. Switch our veiw * of the current sk. */ bh_unlock_sock(sk); sk = rcvr->sk; bh_lock_sock(sk); } if (sock_owned_by_user(sk)) { if (sctp_add_backlog(sk, skb)) { bh_unlock_sock(sk); sctp_chunk_free(chunk); skb = NULL; /* sctp_chunk_free already freed the skb */ goto discard_release; } __SCTP_INC_STATS(net, SCTP_MIB_IN_PKT_BACKLOG); } else { __SCTP_INC_STATS(net, SCTP_MIB_IN_PKT_SOFTIRQ); sctp_inq_push(&chunk->rcvr->inqueue, chunk); } bh_unlock_sock(sk); /* Release the asoc/ep ref we took in the lookup calls. */ if (asoc) sctp_association_put(asoc); else sctp_endpoint_put(ep); return 0; discard_it: __SCTP_INC_STATS(net, SCTP_MIB_IN_PKT_DISCARDS); kfree_skb(skb); return 0; discard_release: /* Release the asoc/ep ref we took in the lookup calls. */ if (asoc) sctp_association_put(asoc); else sctp_endpoint_put(ep); goto discard_it; }

Contributors

PersonTokensPropCommitsCommitProp
jon grimmjon grimm32042.72%816.67%
neil hormanneil horman10113.48%24.17%
marcelo ricardo leitnermarcelo ricardo leitner8110.81%510.42%
vladislav yasevichvladislav yasevich526.94%36.25%
eric w. biedermaneric w. biederman334.41%48.33%
yi zhuyi zhu253.34%12.08%
tom herberttom herbert243.20%12.08%
sridhar samudralasridhar samudrala222.94%510.42%
al viroal viro192.54%36.25%
david s. millerdavid s. miller162.14%48.33%
hideaki yoshifujihideaki yoshifuji131.74%24.17%
herbert xuherbert xu101.34%36.25%
james morrisjames morris101.34%12.08%
arnaldo carvalho de meloarnaldo carvalho de melo81.07%36.25%
wang weidongwang weidong50.67%12.08%
patrick mchardypatrick mchardy50.67%12.08%
eric dumazeteric dumazet50.67%12.08%
Total749100.00%48100.00%

/* Process the backlog queue of the socket. Every skb on * the backlog holds a ref on an association or endpoint. * We hold this ref throughout the state machine to make * sure that the structure we need is still around. */
int sctp_backlog_rcv(struct sock *sk, struct sk_buff *skb) { struct sctp_chunk *chunk = SCTP_INPUT_CB(skb)->chunk; struct sctp_inq *inqueue = &chunk->rcvr->inqueue; struct sctp_ep_common *rcvr = NULL; int backloged = 0; rcvr = chunk->rcvr; /* If the rcvr is dead then the association or endpoint * has been deleted and we can safely drop the chunk * and refs that we are holding. */ if (rcvr->dead) { sctp_chunk_free(chunk); goto done; } if (unlikely(rcvr->sk != sk)) { /* In this case, the association moved from one socket to * another. We are currently sitting on the backlog of the * old socket, so we need to move. * However, since we are here in the process context we * need to take make sure that the user doesn't own * the new socket when we process the packet. * If the new socket is user-owned, queue the chunk to the * backlog of the new socket without dropping any refs. * Otherwise, we can safely push the chunk on the inqueue. */ sk = rcvr->sk; local_bh_disable(); bh_lock_sock(sk); if (sock_owned_by_user(sk)) { if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) sctp_chunk_free(chunk); else backloged = 1; } else sctp_inq_push(inqueue, chunk); bh_unlock_sock(sk); local_bh_enable(); /* If the chunk was backloged again, don't drop refs */ if (backloged) return 0; } else { sctp_inq_push(inqueue, chunk); } done: /* Release the refs we took in sctp_add_backlog */ if (SCTP_EP_TYPE_ASSOCIATION == rcvr->type) sctp_association_put(sctp_assoc(rcvr)); else if (SCTP_EP_TYPE_SOCKET == rcvr->type) sctp_endpoint_put(sctp_ep(rcvr)); else BUG(); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
vladislav yasevichvladislav yasevich9042.65%18.33%
sridhar samudralasridhar samudrala5526.07%18.33%
jon grimmjon grimm3617.06%325.00%
yi zhuyi zhu94.27%216.67%
david s. millerdavid s. miller94.27%216.67%
marcelo ricardo leitnermarcelo ricardo leitner62.84%18.33%
eric dumazeteric dumazet41.90%18.33%
wang weidongwang weidong20.95%18.33%
Total211100.00%12100.00%


static int sctp_add_backlog(struct sock *sk, struct sk_buff *skb) { struct sctp_chunk *chunk = SCTP_INPUT_CB(skb)->chunk; struct sctp_ep_common *rcvr = chunk->rcvr; int ret; ret = sk_add_backlog(sk, skb, sk->sk_rcvbuf); if (!ret) { /* Hold the assoc/ep while hanging on the backlog queue. * This way, we know structures we need will not disappear * from us */ if (SCTP_EP_TYPE_ASSOCIATION == rcvr->type) sctp_association_hold(sctp_assoc(rcvr)); else if (SCTP_EP_TYPE_SOCKET == rcvr->type) sctp_endpoint_hold(sctp_ep(rcvr)); else BUG(); } return ret; }

Contributors

PersonTokensPropCommitsCommitProp
vladislav yasevichvladislav yasevich4039.60%120.00%
sridhar samudralasridhar samudrala3332.67%120.00%
yi zhuyi zhu2423.76%240.00%
eric dumazeteric dumazet43.96%120.00%
Total101100.00%5100.00%

/* Handle icmp frag needed error. */
void sctp_icmp_frag_needed(struct sock *sk, struct sctp_association *asoc, struct sctp_transport *t, __u32 pmtu) { if (!t || (t->pathmtu <= pmtu)) return; if (sock_owned_by_user(sk)) { asoc->pmtu_pending = 1; t->pmtu_pending = 1; return; } if (t->param_flags & SPP_PMTUD_ENABLE) { /* Update transports view of the MTU */ sctp_transport_update_pmtu(sk, t, pmtu); /* Update association pmtu. */ sctp_assoc_sync_pmtu(sk, asoc); } /* Retransmit with the new pmtu setting. * Normally, if PMTU discovery is disabled, an ICMP Fragmentation * Needed will never be sent, but if a message was sent before * PMTU discovery was disabled that was larger than the PMTU, it * would not be fragmented, so it must be re-transmitted fragmented. */ sctp_retransmit(&asoc->outqueue, t, SCTP_RTXR_PMTUD); }

Contributors

PersonTokensPropCommitsCommitProp
sridhar samudralasridhar samudrala4040.00%220.00%
vladislav yasevichvladislav yasevich2525.00%220.00%
frank filzfrank filz2222.00%110.00%
jon grimmjon grimm77.00%220.00%
david s. millerdavid s. miller44.00%110.00%
wei yongjunwei yongjun11.00%110.00%
hideaki yoshifujihideaki yoshifuji11.00%110.00%
Total100100.00%10100.00%


void sctp_icmp_redirect(struct sock *sk, struct sctp_transport *t, struct sk_buff *skb) { struct dst_entry *dst; if (!t) return; dst = sctp_transport_dst_check(t); if (dst) dst->ops->redirect(dst, sk, skb); }

Contributors

PersonTokensPropCommitsCommitProp
david s. millerdavid s. miller55100.00%2100.00%
Total55100.00%2100.00%

/* * SCTP Implementer's Guide, 2.37 ICMP handling procedures * * ICMP8) If the ICMP code is a "Unrecognized next header type encountered" * or a "Protocol Unreachable" treat this message as an abort * with the T bit set. * * This function sends an event to the state machine, which will abort the * association. * */
void sctp_icmp_proto_unreachable(struct sock *sk, struct sctp_association *asoc, struct sctp_transport *t) { if (sock_owned_by_user(sk)) { if (timer_pending(&t->proto_unreach_timer)) return; else { if (!mod_timer(&t->proto_unreach_timer, jiffies + (HZ/20))) sctp_association_hold(asoc); } } else { struct net *net = sock_net(sk); pr_debug("%s: unrecognized next header type " "encountered!\n", __func__); if (del_timer(&t->proto_unreach_timer)) sctp_association_put(asoc); sctp_do_sm(net, SCTP_EVENT_T_OTHER, SCTP_ST_OTHER(SCTP_EVENT_ICMP_PROTO_UNREACH), asoc->state, asoc->ep, asoc, t, GFP_ATOMIC); } }

Contributors

PersonTokensPropCommitsCommitProp
vladislav yasevichvladislav yasevich6550.39%120.00%
sridhar samudralasridhar samudrala4333.33%120.00%
eric w. biedermaneric w. biederman129.30%120.00%
daniel borkmanndaniel borkmann86.20%120.00%
frank filzfrank filz10.78%120.00%
Total129100.00%5100.00%

/* Common lookup code for icmp/icmpv6 error handler. */
struct sock *sctp_err_lookup(struct net *net, int family, struct sk_buff *skb, struct sctphdr *sctphdr, struct sctp_association **app, struct sctp_transport **tpp) { union sctp_addr saddr; union sctp_addr daddr; struct sctp_af *af; struct sock *sk = NULL; struct sctp_association *asoc; struct sctp_transport *transport = NULL; struct sctp_init_chunk *chunkhdr; __u32 vtag = ntohl(sctphdr->vtag); int len = skb->len - ((void *)sctphdr - (void *)skb->data); *app = NULL; *tpp = NULL; af = sctp_get_af_specific(family); if (unlikely(!af)) { return NULL; } /* Initialize local addresses for lookups. */ af->from_skb(&saddr, skb, 1); af->from_skb(&daddr, skb, 0); /* Look for an association that matches the incoming ICMP error * packet. */ asoc = __sctp_lookup_association(net, &saddr, &daddr, &transport); if (!asoc) return NULL; sk = asoc->base.sk; /* RFC 4960, Appendix C. ICMP Handling * * ICMP6) An implementation MUST validate that the Verification Tag * contained in the ICMP message matches the Verification Tag of * the peer. If the Verification Tag is not 0 and does NOT * match, discard the ICMP message. If it is 0 and the ICMP * message contains enough bytes to verify that the chunk type is * an INIT chunk and that the Initiate Tag matches the tag of the * peer, continue with ICMP7. If the ICMP message is too short * or the chunk type or the Initiate Tag does not match, silently * discard the packet. */ if (vtag == 0) { chunkhdr = (void *)sctphdr + sizeof(struct sctphdr); if (len < sizeof(struct sctphdr) + sizeof(sctp_chunkhdr_t) + sizeof(__be32) || chunkhdr->chunk_hdr.type != SCTP_CID_INIT || ntohl(chunkhdr->init_hdr.init_tag) != asoc->c.my_vtag) { goto out; } } else if (vtag != asoc->c.peer_vtag) { goto out; } bh_lock_sock(sk); /* If too many ICMPs get dropped on busy * servers this needs to be solved differently. */ if (sock_owned_by_user(sk)) __NET_INC_STATS(net, LINUX_MIB_LOCKDROPPEDICMPS); *app = asoc; *tpp = transport; return sk; out: sctp_association_put(asoc); return NULL; }

Contributors

PersonTokensPropCommitsCommitProp
jon grimmjon grimm11234.46%426.67%
wei yongjunwei yongjun10732.92%16.67%
sridhar samudralasridhar samudrala9128.00%213.33%
eric w. biedermaneric w. biederman82.46%213.33%
al viroal viro20.62%16.67%
wang weidongwang weidong10.31%16.67%
pavel emelianovpavel emelianov10.31%16.67%
hideaki yoshifujihideaki yoshifuji10.31%16.67%
eric dumazeteric dumazet10.31%16.67%
david s. millerdavid s. miller10.31%16.67%
Total325100.00%15100.00%

/* Common cleanup code for icmp/icmpv6 error handler. */
void sctp_err_finish(struct sock *sk, struct sctp_association *asoc) { bh_unlock_sock(sk); sctp_association_put(asoc); }

Contributors

PersonTokensPropCommitsCommitProp
jon grimmjon grimm2496.00%150.00%
wang weidongwang weidong14.00%150.00%
Total25100.00%2100.00%

/* * This routine is called by the ICMP module when it gets some * sort of error condition. If err < 0 then the socket should * be closed and the error returned to the user. If err > 0 * it's just the icmp type << 8 | icmp code. After adjustment * header points to the first 8 bytes of the sctp header. We need * to find the appropriate port. * * The locking strategy used here is very "optimistic". When * someone else accesses the socket the ICMP is just dropped * and for some paths there is no check at all. * A more general error queue to queue errors for later handling * is probably better. * */
void sctp_v4_err(struct sk_buff *skb, __u32 info) { const struct iphdr *iph = (const struct iphdr *)skb->data; const int ihlen = iph->ihl * 4; const int type = icmp_hdr(skb)->type; const int code = icmp_hdr(skb)->code; struct sock *sk; struct sctp_association *asoc = NULL; struct sctp_transport *transport; struct inet_sock *inet; __u16 saveip, savesctp; int err; struct net *net = dev_net(skb->dev); /* Fix up skb to look at the embedded net header. */ saveip = skb->network_header; savesctp = skb->transport_header; skb_reset_network_header(skb); skb_set_transport_header(skb, ihlen); sk = sctp_err_lookup(net, AF_INET, skb, sctp_hdr(skb), &asoc, &transport); /* Put back, the original values. */ skb->network_header = saveip; skb->transport_header = savesctp; if (!sk) { __ICMP_INC_STATS(net, ICMP_MIB_INERRORS); return; } /* Warning: The sock lock is held. Remember to call * sctp_err_finish! */ switch (type) { case ICMP_PARAMETERPROB: err = EPROTO; break; case ICMP_DEST_UNREACH: if (code > NR_ICMP_UNREACH) goto out_unlock; /* PMTU discovery (RFC1191) */ if (ICMP_FRAG_NEEDED == code) { sctp_icmp_frag_needed(sk, asoc, transport, WORD_TRUNC(info)); goto out_unlock; } else { if (ICMP_PROT_UNREACH == code) { sctp_icmp_proto_unreachable(sk, asoc, transport); goto out_unlock; } } err = icmp_err_convert[code].errno; break; case ICMP_TIME_EXCEEDED: /* Ignore any time exceeded errors due to fragment reassembly * timeouts. */ if (ICMP_EXC_FRAGTIME == code) goto out_unlock; err = EHOSTUNREACH; break; case ICMP_REDIRECT: sctp_icmp_redirect(sk, transport, skb); /* Fall through to out_unlock. */ default: goto out_unlock; } inet = inet_sk(sk); if (!sock_owned_by_user(sk) && inet->recverr) { sk->sk_err = err; sk->sk_error_report(sk); } else { /* Only an error on timeout */ sk->sk_err_soft = err; } out_unlock: sctp_err_finish(sk, asoc); }

Contributors

PersonTokensPropCommitsCommitProp
jon grimmjon grimm17449.43%312.50%
sridhar samudralasridhar samudrala10730.40%416.67%
arnaldo carvalho de meloarnaldo carvalho de melo349.66%729.17%
eric w. biedermaneric w. biederman154.26%28.33%
david s. millerdavid s. miller123.41%14.17%
marcelo ricardo leitnermarcelo ricardo leitner30.85%14.17%
eric dumazeteric dumazet30.85%28.33%
daniel borkmanndaniel borkmann10.28%14.17%
pavel emelianovpavel emelianov10.28%14.17%
hideaki yoshifujihideaki yoshifuji10.28%14.17%
simon hormansimon horman10.28%14.17%
Total352100.00%24100.00%

/* * RFC 2960, 8.4 - Handle "Out of the blue" Packets. * * This function scans all the chunks in the OOTB packet to determine if * the packet should be discarded right away. If a response might be needed * for this packet, or, if further processing is possible, the packet will * be queued to a proper inqueue for the next phase of handling. * * Output: * Return 0 - If further processing is needed. * Return 1 - If the packet can be discarded right away. */
static int sctp_rcv_ootb(struct sk_buff *skb) { sctp_chunkhdr_t *ch, _ch; int ch_end, offset = 0; /* Scan through all the chunks in the packet. */ do { /* Make sure we have at least the header there */ if (offset + sizeof(sctp_chunkhdr_t) > skb->len) break; ch = skb_header_pointer(skb, offset, sizeof(*ch), &_ch); /* Break out if chunk length is less then minimal. */ if (ntohs(ch->length) < sizeof(sctp_chunkhdr_t)) break; ch_end = offset + WORD_ROUND(ntohs(ch->length)); if (ch_end > skb->len) break; /* RFC 8.4, 2) If the OOTB packet contains an ABORT chunk, the * receiver MUST silently discard the OOTB packet and take no * further action. */ if (SCTP_CID_ABORT == ch->type) goto discard; /* RFC 8.4, 6) If the packet contains a SHUTDOWN COMPLETE * chunk, the receiver should silently discard the packet * and take no further action. */ if (SCTP_CID_SHUTDOWN_COMPLETE == ch->type) goto discard; /* RFC 4460, 2.11.2 * This will discard packets with INIT chunk bundled as * subsequent chunks in the packet. When INIT is first, * the normal INIT processing will discard the chunk. */ if (SCTP_CID_INIT == ch->type && (void *)ch != skb->data) goto discard; offset = ch_end; } while (ch_end < skb->len); return 0; discard: return 1; }

Contributors

PersonTokensPropCommitsCommitProp
jon grimmjon grimm6438.32%112.50%
marcelo ricardo leitnermarcelo ricardo leitner4526.95%112.50%
tsutomu fujiitsutomu fujii2514.97%112.50%
vladislav yasevichvladislav yasevich2213.17%112.50%
sridhar samudralasridhar samudrala74.19%225.00%
david s. millerdavid s. miller31.80%112.50%
sebastian andrzej siewiorsebastian andrzej siewior10.60%112.50%
Total167100.00%8100.00%

/* Insert endpoint into the hash table. */
static void __sctp_hash_endpoint(struct sctp_endpoint *ep) { struct net *net = sock_net(ep->base.sk); struct sctp_ep_common *epb; struct sctp_hashbucket *head; epb = &ep->base; epb->hashent = sctp_ep_hashfn(net, epb->bind_addr.port); head = &sctp_ep_hashtable[epb->hashent]; write_lock(&head->lock); hlist_add_head(&epb->node, &head->chain); write_unlock(&head->lock); }

Contributors

PersonTokensPropCommitsCommitProp
jon grimmjon grimm6971.88%337.50%
eric w. biedermaneric w. biederman1616.67%112.50%
vladislav yasevichvladislav yasevich77.29%112.50%
sridhar samudralasridhar samudrala22.08%225.00%
wang weidongwang weidong22.08%112.50%
Total96100.00%8100.00%

/* Add an endpoint to the hash. Local BH-safe. */
void sctp_hash_endpoint(struct sctp_endpoint *ep) { local_bh_disable(); __sctp_hash_endpoint(ep); local_bh_enable(); }

Contributors

PersonTokensPropCommitsCommitProp
jon grimmjon grimm1990.48%266.67%
wang weidongwang weidong29.52%133.33%
Total21100.00%3100.00%

/* Remove endpoint from the hash table. */
static void __sctp_unhash_endpoint(struct sctp_endpoint *ep) { struct net *net = sock_net(ep->base.sk); struct sctp_hashbucket *head; struct sctp_ep_common *epb; epb = &ep->base; epb->hashent = sctp_ep_hashfn(net, epb->bind_addr.port); head = &sctp_ep_hashtable[epb->hashent]; write_lock(&head->lock); hlist_del_init(&epb->node); write_unlock(&head->lock); }

Contributors

PersonTokensPropCommitsCommitProp
jon grimmjon grimm6672.53%333.33%
eric w. biedermaneric w. biederman1617.58%111.11%
vladislav yasevichvladislav yasevich44.40%111.11%
wang weidongwang weidong22.20%111.11%
sridhar samudralasridhar samudrala22.20%222.22%
neil hormanneil horman11.10%111.11%
Total91100.00%9100.00%

/* Remove endpoint from the hash. Local BH-safe. */
void sctp_unhash_endpoint(struct sctp_endpoint *ep) { local_bh_disable(); __sctp_unhash_endpoint(ep); local_bh_enable(); }

Contributors

PersonTokensPropCommitsCommitProp
jon grimmjon grimm1990.48%266.67%
wang weidongwang weidong29.52%133.33%
Total21100.00%3100.00%

/* Look up an endpoint. */
static struct sctp_endpoint *__sctp_rcv_lookup_endpoint(struct net *net, const union sctp_addr *laddr) { struct sctp_hashbucket *head; struct sctp_ep_common *epb; struct sctp_endpoint *ep; int hash; hash = sctp_ep_hashfn(net, ntohs(laddr->v4.sin_port)); head = &sctp_ep_hashtable[hash]; read_lock(&head->lock); sctp_for_each_hentry(epb, &head->chain) { ep = sctp_ep(epb); if (sctp_endpoint_is_match(ep, net, laddr)) goto hit; } ep = sctp_sk(net->sctp.ctl_sock)->ep; hit: sctp_endpoint_hold(ep); read_unlock(&head->lock); return ep; }

Contributors

PersonTokensPropCommitsCommitProp
jon grimmjon grimm10480.62%440.00%
eric w. biedermaneric w. biederman1410.85%220.00%
vladislav yasevichvladislav yasevich64.65%110.00%
al viroal viro32.33%110.00%
sridhar samudralasridhar samudrala21.55%220.00%
Total129100.00%10100.00%

/* rhashtable for transport */ struct sctp_hash_cmp_arg { const struct sctp_endpoint *ep; const union sctp_addr *laddr; const union sctp_addr *paddr; const struct net *net; };
static inline int sctp_hash_cmp(struct rhashtable_compare_arg *arg,