^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) * (C) Copyright IBM Corp. 2001, 2004
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) * Copyright (c) 1999-2000 Cisco, Inc.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Copyright (c) 1999-2001 Motorola, Inc.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) * This file is part of the SCTP kernel implementation
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) * These functions handle output processing.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) * Please send any bug reports or fixes you make to the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) * email address(es):
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) * lksctp developers <linux-sctp@vger.kernel.org>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) * Written or modified by:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) * La Monte H.P. Yarroll <piggy@acm.org>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) * Karl Knutson <karl@athena.chicago.il.us>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) * Jon Grimm <jgrimm@austin.ibm.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) * Sridhar Samudrala <sri@us.ibm.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) #include <linux/types.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) #include <linux/wait.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) #include <linux/time.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) #include <linux/ip.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) #include <linux/ipv6.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) #include <linux/init.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) #include <net/inet_ecn.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) #include <net/ip.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) #include <net/icmp.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) #include <net/net_namespace.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) #include <linux/socket.h> /* for sa_family_t */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) #include <net/sock.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39)
^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)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) /* Forward declarations for private helpers. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) static enum sctp_xmit __sctp_packet_append_chunk(struct sctp_packet *packet,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) struct sctp_chunk *chunk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) static enum sctp_xmit sctp_packet_can_append_data(struct sctp_packet *packet,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) struct sctp_chunk *chunk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) static void sctp_packet_append_data(struct sctp_packet *packet,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) struct sctp_chunk *chunk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) static enum sctp_xmit sctp_packet_will_fit(struct sctp_packet *packet,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) struct sctp_chunk *chunk,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) u16 chunk_len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) static void sctp_packet_reset(struct sctp_packet *packet)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) /* sctp_packet_transmit() relies on this to reset size to the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) * current overhead after sending packets.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) packet->size = packet->overhead;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) packet->has_cookie_echo = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) packet->has_sack = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) packet->has_data = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) packet->has_auth = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) packet->ipfragok = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) packet->auth = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) /* Config a packet.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) * This appears to be a followup set of initializations.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) void sctp_packet_config(struct sctp_packet *packet, __u32 vtag,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) int ecn_capable)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) struct sctp_transport *tp = packet->transport;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) struct sctp_association *asoc = tp->asoc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) struct sctp_sock *sp = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) struct sock *sk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) pr_debug("%s: packet:%p vtag:0x%x\n", __func__, packet, vtag);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) packet->vtag = vtag;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) /* do the following jobs only once for a flush schedule */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) if (!sctp_packet_empty(packet))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) /* set packet max_size with pathmtu, then calculate overhead */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) packet->max_size = tp->pathmtu;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) if (asoc) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) sk = asoc->base.sk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) sp = sctp_sk(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) packet->overhead = sctp_mtu_payload(sp, 0, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) packet->size = packet->overhead;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) if (!asoc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) /* update dst or transport pathmtu if in need */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) if (!sctp_transport_dst_check(tp)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) sctp_transport_route(tp, NULL, sp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) if (asoc->param_flags & SPP_PMTUD_ENABLE)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) sctp_assoc_sync_pmtu(asoc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) } else if (!sctp_transport_pmtu_check(tp)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) if (asoc->param_flags & SPP_PMTUD_ENABLE)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) sctp_assoc_sync_pmtu(asoc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) if (asoc->pmtu_pending) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) if (asoc->param_flags & SPP_PMTUD_ENABLE)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) sctp_assoc_sync_pmtu(asoc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) asoc->pmtu_pending = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) /* If there a is a prepend chunk stick it on the list before
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) * any other chunks get appended.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) if (ecn_capable) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) struct sctp_chunk *chunk = sctp_get_ecne_prepend(asoc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) if (chunk)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) sctp_packet_append_chunk(packet, chunk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) if (!tp->dst)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) /* set packet max_size with gso_max_size if gso is enabled*/
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) rcu_read_lock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) if (__sk_dst_get(sk) != tp->dst) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) dst_hold(tp->dst);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) sk_setup_caps(sk, tp->dst);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) packet->max_size = sk_can_gso(sk) ? tp->dst->dev->gso_max_size
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) : asoc->pathmtu;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) /* Initialize the packet structure. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) void sctp_packet_init(struct sctp_packet *packet,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) struct sctp_transport *transport,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) __u16 sport, __u16 dport)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) pr_debug("%s: packet:%p transport:%p\n", __func__, packet, transport);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) packet->transport = transport;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) packet->source_port = sport;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) packet->destination_port = dport;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) INIT_LIST_HEAD(&packet->chunk_list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) /* The overhead will be calculated by sctp_packet_config() */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) packet->overhead = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) sctp_packet_reset(packet);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) packet->vtag = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) /* Free a packet. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) void sctp_packet_free(struct sctp_packet *packet)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) struct sctp_chunk *chunk, *tmp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) pr_debug("%s: packet:%p\n", __func__, packet);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) list_for_each_entry_safe(chunk, tmp, &packet->chunk_list, list) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) list_del_init(&chunk->list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) sctp_chunk_free(chunk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) /* This routine tries to append the chunk to the offered packet. If adding
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) * the chunk causes the packet to exceed the path MTU and COOKIE_ECHO chunk
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) * is not present in the packet, it transmits the input packet.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) * Data can be bundled with a packet containing a COOKIE_ECHO chunk as long
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) * as it can fit in the packet, but any more data that does not fit in this
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) * packet can be sent only after receiving the COOKIE_ACK.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) enum sctp_xmit sctp_packet_transmit_chunk(struct sctp_packet *packet,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) struct sctp_chunk *chunk,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) int one_packet, gfp_t gfp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) enum sctp_xmit retval;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) pr_debug("%s: packet:%p size:%zu chunk:%p size:%d\n", __func__,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) packet, packet->size, chunk, chunk->skb ? chunk->skb->len : -1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) switch ((retval = (sctp_packet_append_chunk(packet, chunk)))) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) case SCTP_XMIT_PMTU_FULL:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) if (!packet->has_cookie_echo) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) int error = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) error = sctp_packet_transmit(packet, gfp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) if (error < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) chunk->skb->sk->sk_err = -error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) /* If we have an empty packet, then we can NOT ever
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) * return PMTU_FULL.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) if (!one_packet)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) retval = sctp_packet_append_chunk(packet,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) chunk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) case SCTP_XMIT_RWND_FULL:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) case SCTP_XMIT_OK:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) case SCTP_XMIT_DELAY:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) return retval;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) /* Try to bundle an auth chunk into the packet. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) static enum sctp_xmit sctp_packet_bundle_auth(struct sctp_packet *pkt,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) struct sctp_chunk *chunk)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) struct sctp_association *asoc = pkt->transport->asoc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) enum sctp_xmit retval = SCTP_XMIT_OK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) struct sctp_chunk *auth;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) /* if we don't have an association, we can't do authentication */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) if (!asoc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) return retval;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) /* See if this is an auth chunk we are bundling or if
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) * auth is already bundled.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229) if (chunk->chunk_hdr->type == SCTP_CID_AUTH || pkt->has_auth)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) return retval;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) /* if the peer did not request this chunk to be authenticated,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) * don't do it
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) if (!chunk->auth)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) return retval;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) auth = sctp_make_auth(asoc, chunk->shkey->key_id);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) if (!auth)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) return retval;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) auth->shkey = chunk->shkey;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243) sctp_auth_shkey_hold(auth->shkey);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245) retval = __sctp_packet_append_chunk(pkt, auth);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) if (retval != SCTP_XMIT_OK)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) sctp_chunk_free(auth);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250) return retval;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) /* Try to bundle a SACK with the packet. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) static enum sctp_xmit sctp_packet_bundle_sack(struct sctp_packet *pkt,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) struct sctp_chunk *chunk)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257) enum sctp_xmit retval = SCTP_XMIT_OK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259) /* If sending DATA and haven't aleady bundled a SACK, try to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) * bundle one in to the packet.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) if (sctp_chunk_is_data(chunk) && !pkt->has_sack &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) !pkt->has_cookie_echo) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) struct sctp_association *asoc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265) struct timer_list *timer;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) asoc = pkt->transport->asoc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) timer = &asoc->timers[SCTP_EVENT_TIMEOUT_SACK];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) /* If the SACK timer is running, we have a pending SACK */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) if (timer_pending(timer)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) struct sctp_chunk *sack;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273) if (pkt->transport->sack_generation !=
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) pkt->transport->asoc->peer.sack_generation)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) return retval;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277) asoc->a_rwnd = asoc->rwnd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278) sack = sctp_make_sack(asoc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) if (sack) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280) retval = __sctp_packet_append_chunk(pkt, sack);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) if (retval != SCTP_XMIT_OK) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282) sctp_chunk_free(sack);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) SCTP_INC_STATS(asoc->base.net,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) SCTP_MIB_OUTCTRLCHUNKS);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287) asoc->stats.octrlchunks++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) asoc->peer.sack_needed = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) if (del_timer(timer))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290) sctp_association_put(asoc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295) return retval;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299) /* Append a chunk to the offered packet reporting back any inability to do
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300) * so.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302) static enum sctp_xmit __sctp_packet_append_chunk(struct sctp_packet *packet,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) struct sctp_chunk *chunk)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305) __u16 chunk_len = SCTP_PAD4(ntohs(chunk->chunk_hdr->length));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306) enum sctp_xmit retval = SCTP_XMIT_OK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308) /* Check to see if this chunk will fit into the packet */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309) retval = sctp_packet_will_fit(packet, chunk, chunk_len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310) if (retval != SCTP_XMIT_OK)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311) goto finish;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313) /* We believe that this chunk is OK to add to the packet */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314) switch (chunk->chunk_hdr->type) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315) case SCTP_CID_DATA:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316) case SCTP_CID_I_DATA:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) /* Account for the data being in the packet */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318) sctp_packet_append_data(packet, chunk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319) /* Disallow SACK bundling after DATA. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) packet->has_sack = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321) /* Disallow AUTH bundling after DATA */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322) packet->has_auth = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323) /* Let it be knows that packet has DATA in it */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324) packet->has_data = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325) /* timestamp the chunk for rtx purposes */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326) chunk->sent_at = jiffies;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327) /* Mainly used for prsctp RTX policy */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328) chunk->sent_count++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330) case SCTP_CID_COOKIE_ECHO:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331) packet->has_cookie_echo = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334) case SCTP_CID_SACK:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335) packet->has_sack = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 336) if (chunk->asoc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 337) chunk->asoc->stats.osacks++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 338) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 339)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 340) case SCTP_CID_AUTH:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 341) packet->has_auth = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 342) packet->auth = chunk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 343) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 344) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 345)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 346) /* It is OK to send this chunk. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 347) list_add_tail(&chunk->list, &packet->chunk_list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 348) packet->size += chunk_len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 349) chunk->transport = packet->transport;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 350) finish:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 351) return retval;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 352) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 353)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 354) /* Append a chunk to the offered packet reporting back any inability to do
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 355) * so.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 356) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 357) enum sctp_xmit sctp_packet_append_chunk(struct sctp_packet *packet,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 358) struct sctp_chunk *chunk)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 359) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 360) enum sctp_xmit retval = SCTP_XMIT_OK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 361)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 362) pr_debug("%s: packet:%p chunk:%p\n", __func__, packet, chunk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 363)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 364) /* Data chunks are special. Before seeing what else we can
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 365) * bundle into this packet, check to see if we are allowed to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 366) * send this DATA.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 367) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 368) if (sctp_chunk_is_data(chunk)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 369) retval = sctp_packet_can_append_data(packet, chunk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 370) if (retval != SCTP_XMIT_OK)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 371) goto finish;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 372) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 373)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 374) /* Try to bundle AUTH chunk */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 375) retval = sctp_packet_bundle_auth(packet, chunk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 376) if (retval != SCTP_XMIT_OK)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 377) goto finish;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 378)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 379) /* Try to bundle SACK chunk */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 380) retval = sctp_packet_bundle_sack(packet, chunk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 381) if (retval != SCTP_XMIT_OK)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 382) goto finish;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 383)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 384) retval = __sctp_packet_append_chunk(packet, chunk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 385)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 386) finish:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 387) return retval;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 388) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 389)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 390) static void sctp_packet_gso_append(struct sk_buff *head, struct sk_buff *skb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 391) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 392) if (SCTP_OUTPUT_CB(head)->last == head)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 393) skb_shinfo(head)->frag_list = skb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 394) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 395) SCTP_OUTPUT_CB(head)->last->next = skb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 396) SCTP_OUTPUT_CB(head)->last = skb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 397)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 398) head->truesize += skb->truesize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 399) head->data_len += skb->len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 400) head->len += skb->len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 401) refcount_add(skb->truesize, &head->sk->sk_wmem_alloc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 402)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 403) __skb_header_release(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 404) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 405)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 406) static int sctp_packet_pack(struct sctp_packet *packet,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 407) struct sk_buff *head, int gso, gfp_t gfp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 408) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 409) struct sctp_transport *tp = packet->transport;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 410) struct sctp_auth_chunk *auth = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 411) struct sctp_chunk *chunk, *tmp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 412) int pkt_count = 0, pkt_size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 413) struct sock *sk = head->sk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 414) struct sk_buff *nskb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 415) int auth_len = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 416)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 417) if (gso) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 418) skb_shinfo(head)->gso_type = sk->sk_gso_type;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 419) SCTP_OUTPUT_CB(head)->last = head;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 420) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 421) nskb = head;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 422) pkt_size = packet->size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 423) goto merge;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 424) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 425)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 426) do {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 427) /* calculate the pkt_size and alloc nskb */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 428) pkt_size = packet->overhead;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 429) list_for_each_entry_safe(chunk, tmp, &packet->chunk_list,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 430) list) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 431) int padded = SCTP_PAD4(chunk->skb->len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 432)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 433) if (chunk == packet->auth)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 434) auth_len = padded;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 435) else if (auth_len + padded + packet->overhead >
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 436) tp->pathmtu)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 437) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 438) else if (pkt_size + padded > tp->pathmtu)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 439) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 440) pkt_size += padded;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 441) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 442) nskb = alloc_skb(pkt_size + MAX_HEADER, gfp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 443) if (!nskb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 444) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 445) skb_reserve(nskb, packet->overhead + MAX_HEADER);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 446)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 447) merge:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 448) /* merge chunks into nskb and append nskb into head list */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 449) pkt_size -= packet->overhead;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 450) list_for_each_entry_safe(chunk, tmp, &packet->chunk_list, list) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 451) int padding;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 452)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 453) list_del_init(&chunk->list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 454) if (sctp_chunk_is_data(chunk)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 455) if (!sctp_chunk_retransmitted(chunk) &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 456) !tp->rto_pending) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 457) chunk->rtt_in_progress = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 458) tp->rto_pending = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 459) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 460) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 461)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 462) padding = SCTP_PAD4(chunk->skb->len) - chunk->skb->len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 463) if (padding)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 464) skb_put_zero(chunk->skb, padding);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 465)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 466) if (chunk == packet->auth)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 467) auth = (struct sctp_auth_chunk *)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 468) skb_tail_pointer(nskb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 469)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 470) skb_put_data(nskb, chunk->skb->data, chunk->skb->len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 471)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 472) pr_debug("*** Chunk:%p[%s] %s 0x%x, length:%d, chunk->skb->len:%d, rtt_in_progress:%d\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 473) chunk,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 474) sctp_cname(SCTP_ST_CHUNK(chunk->chunk_hdr->type)),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 475) chunk->has_tsn ? "TSN" : "No TSN",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 476) chunk->has_tsn ? ntohl(chunk->subh.data_hdr->tsn) : 0,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 477) ntohs(chunk->chunk_hdr->length), chunk->skb->len,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 478) chunk->rtt_in_progress);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 479)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 480) pkt_size -= SCTP_PAD4(chunk->skb->len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 481)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 482) if (!sctp_chunk_is_data(chunk) && chunk != packet->auth)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 483) sctp_chunk_free(chunk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 484)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 485) if (!pkt_size)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 486) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 487) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 488)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 489) if (auth) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 490) sctp_auth_calculate_hmac(tp->asoc, nskb, auth,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 491) packet->auth->shkey, gfp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 492) /* free auth if no more chunks, or add it back */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 493) if (list_empty(&packet->chunk_list))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 494) sctp_chunk_free(packet->auth);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 495) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 496) list_add(&packet->auth->list,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 497) &packet->chunk_list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 498) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 499)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 500) if (gso)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 501) sctp_packet_gso_append(head, nskb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 502)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 503) pkt_count++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 504) } while (!list_empty(&packet->chunk_list));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 505)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 506) if (gso) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 507) memset(head->cb, 0, max(sizeof(struct inet_skb_parm),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 508) sizeof(struct inet6_skb_parm)));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 509) skb_shinfo(head)->gso_segs = pkt_count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 510) skb_shinfo(head)->gso_size = GSO_BY_FRAGS;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 511) rcu_read_lock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 512) if (skb_dst(head) != tp->dst) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 513) dst_hold(tp->dst);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 514) sk_setup_caps(sk, tp->dst);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 515) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 516) rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 517) goto chksum;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 518) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 519)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 520) if (sctp_checksum_disable)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 521) return 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 522)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 523) if (!(skb_dst(head)->dev->features & NETIF_F_SCTP_CRC) ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 524) dst_xfrm(skb_dst(head)) || packet->ipfragok) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 525) struct sctphdr *sh =
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 526) (struct sctphdr *)skb_transport_header(head);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 527)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 528) sh->checksum = sctp_compute_cksum(head, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 529) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 530) chksum:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 531) head->ip_summed = CHECKSUM_PARTIAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 532) head->csum_not_inet = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 533) head->csum_start = skb_transport_header(head) - head->head;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 534) head->csum_offset = offsetof(struct sctphdr, checksum);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 535) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 536)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 537) return pkt_count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 538) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 539)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 540) /* All packets are sent to the network through this function from
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 541) * sctp_outq_tail().
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 542) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 543) * The return value is always 0 for now.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 544) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 545) int sctp_packet_transmit(struct sctp_packet *packet, gfp_t gfp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 546) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 547) struct sctp_transport *tp = packet->transport;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 548) struct sctp_association *asoc = tp->asoc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 549) struct sctp_chunk *chunk, *tmp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 550) int pkt_count, gso = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 551) struct dst_entry *dst;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 552) struct sk_buff *head;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 553) struct sctphdr *sh;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 554) struct sock *sk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 555)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 556) pr_debug("%s: packet:%p\n", __func__, packet);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 557) if (list_empty(&packet->chunk_list))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 558) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 559) chunk = list_entry(packet->chunk_list.next, struct sctp_chunk, list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 560) sk = chunk->skb->sk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 561)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 562) /* check gso */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 563) if (packet->size > tp->pathmtu && !packet->ipfragok) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 564) if (!sk_can_gso(sk)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 565) pr_err_once("Trying to GSO but underlying device doesn't support it.");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 566) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 567) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 568) gso = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 569) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 570)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 571) /* alloc head skb */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 572) head = alloc_skb((gso ? packet->overhead : packet->size) +
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 573) MAX_HEADER, gfp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 574) if (!head)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 575) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 576) skb_reserve(head, packet->overhead + MAX_HEADER);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 577) skb_set_owner_w(head, sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 578)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 579) /* set sctp header */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 580) sh = skb_push(head, sizeof(struct sctphdr));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 581) skb_reset_transport_header(head);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 582) sh->source = htons(packet->source_port);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 583) sh->dest = htons(packet->destination_port);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 584) sh->vtag = htonl(packet->vtag);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 585) sh->checksum = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 586)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 587) /* drop packet if no dst */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 588) dst = dst_clone(tp->dst);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 589) if (!dst) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 590) IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTNOROUTES);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 591) kfree_skb(head);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 592) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 593) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 594) skb_dst_set(head, dst);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 595)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 596) /* pack up chunks */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 597) pkt_count = sctp_packet_pack(packet, head, gso, gfp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 598) if (!pkt_count) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 599) kfree_skb(head);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 600) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 601) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 602) pr_debug("***sctp_transmit_packet*** skb->len:%d\n", head->len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 603)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 604) /* start autoclose timer */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 605) if (packet->has_data && sctp_state(asoc, ESTABLISHED) &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 606) asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE]) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 607) struct timer_list *timer =
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 608) &asoc->timers[SCTP_EVENT_TIMEOUT_AUTOCLOSE];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 609) unsigned long timeout =
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 610) asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 611)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 612) if (!mod_timer(timer, jiffies + timeout))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 613) sctp_association_hold(asoc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 614) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 615)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 616) /* sctp xmit */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 617) tp->af_specific->ecn_capable(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 618) if (asoc) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 619) asoc->stats.opackets += pkt_count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 620) if (asoc->peer.last_sent_to != tp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 621) asoc->peer.last_sent_to = tp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 622) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 623) head->ignore_df = packet->ipfragok;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 624) if (tp->dst_pending_confirm)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 625) skb_set_dst_pending_confirm(head, 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 626) /* neighbour should be confirmed on successful transmission or
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 627) * positive error
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 628) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 629) if (tp->af_specific->sctp_xmit(head, tp) >= 0 &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 630) tp->dst_pending_confirm)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 631) tp->dst_pending_confirm = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 632)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 633) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 634) list_for_each_entry_safe(chunk, tmp, &packet->chunk_list, list) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 635) list_del_init(&chunk->list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 636) if (!sctp_chunk_is_data(chunk))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 637) sctp_chunk_free(chunk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 638) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 639) sctp_packet_reset(packet);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 640) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 641) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 642)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 643) /********************************************************************
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 644) * 2nd Level Abstractions
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 645) ********************************************************************/
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 646)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 647) /* This private function check to see if a chunk can be added */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 648) static enum sctp_xmit sctp_packet_can_append_data(struct sctp_packet *packet,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 649) struct sctp_chunk *chunk)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 650) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 651) size_t datasize, rwnd, inflight, flight_size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 652) struct sctp_transport *transport = packet->transport;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 653) struct sctp_association *asoc = transport->asoc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 654) struct sctp_outq *q = &asoc->outqueue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 655)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 656) /* RFC 2960 6.1 Transmission of DATA Chunks
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 657) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 658) * A) At any given time, the data sender MUST NOT transmit new data to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 659) * any destination transport address if its peer's rwnd indicates
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 660) * that the peer has no buffer space (i.e. rwnd is 0, see Section
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 661) * 6.2.1). However, regardless of the value of rwnd (including if it
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 662) * is 0), the data sender can always have one DATA chunk in flight to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 663) * the receiver if allowed by cwnd (see rule B below). This rule
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 664) * allows the sender to probe for a change in rwnd that the sender
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 665) * missed due to the SACK having been lost in transit from the data
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 666) * receiver to the data sender.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 667) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 668)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 669) rwnd = asoc->peer.rwnd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 670) inflight = q->outstanding_bytes;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 671) flight_size = transport->flight_size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 672)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 673) datasize = sctp_data_size(chunk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 674)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 675) if (datasize > rwnd && inflight > 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 676) /* We have (at least) one data chunk in flight,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 677) * so we can't fall back to rule 6.1 B).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 678) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 679) return SCTP_XMIT_RWND_FULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 680)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 681) /* RFC 2960 6.1 Transmission of DATA Chunks
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 682) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 683) * B) At any given time, the sender MUST NOT transmit new data
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 684) * to a given transport address if it has cwnd or more bytes
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 685) * of data outstanding to that transport address.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 686) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 687) /* RFC 7.2.4 & the Implementers Guide 2.8.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 688) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 689) * 3) ...
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 690) * When a Fast Retransmit is being performed the sender SHOULD
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 691) * ignore the value of cwnd and SHOULD NOT delay retransmission.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 692) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 693) if (chunk->fast_retransmit != SCTP_NEED_FRTX &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 694) flight_size >= transport->cwnd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 695) return SCTP_XMIT_RWND_FULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 696)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 697) /* Nagle's algorithm to solve small-packet problem:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 698) * Inhibit the sending of new chunks when new outgoing data arrives
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 699) * if any previously transmitted data on the connection remains
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 700) * unacknowledged.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 701) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 702)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 703) if ((sctp_sk(asoc->base.sk)->nodelay || inflight == 0) &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 704) !asoc->force_delay)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 705) /* Nothing unacked */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 706) return SCTP_XMIT_OK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 707)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 708) if (!sctp_packet_empty(packet))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 709) /* Append to packet */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 710) return SCTP_XMIT_OK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 711)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 712) if (!sctp_state(asoc, ESTABLISHED))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 713) return SCTP_XMIT_OK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 714)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 715) /* Check whether this chunk and all the rest of pending data will fit
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 716) * or delay in hopes of bundling a full sized packet.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 717) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 718) if (chunk->skb->len + q->out_qlen > transport->pathmtu -
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 719) packet->overhead - sctp_datachk_len(&chunk->asoc->stream) - 4)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 720) /* Enough data queued to fill a packet */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 721) return SCTP_XMIT_OK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 722)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 723) /* Don't delay large message writes that may have been fragmented */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 724) if (!chunk->msg->can_delay)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 725) return SCTP_XMIT_OK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 726)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 727) /* Defer until all data acked or packet full */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 728) return SCTP_XMIT_DELAY;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 729) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 730)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 731) /* This private function does management things when adding DATA chunk */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 732) static void sctp_packet_append_data(struct sctp_packet *packet,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 733) struct sctp_chunk *chunk)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 734) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 735) struct sctp_transport *transport = packet->transport;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 736) size_t datasize = sctp_data_size(chunk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 737) struct sctp_association *asoc = transport->asoc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 738) u32 rwnd = asoc->peer.rwnd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 739)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 740) /* Keep track of how many bytes are in flight over this transport. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 741) transport->flight_size += datasize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 742)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 743) /* Keep track of how many bytes are in flight to the receiver. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 744) asoc->outqueue.outstanding_bytes += datasize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 745)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 746) /* Update our view of the receiver's rwnd. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 747) if (datasize < rwnd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 748) rwnd -= datasize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 749) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 750) rwnd = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 751)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 752) asoc->peer.rwnd = rwnd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 753) sctp_chunk_assign_tsn(chunk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 754) asoc->stream.si->assign_number(chunk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 755) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 756)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 757) static enum sctp_xmit sctp_packet_will_fit(struct sctp_packet *packet,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 758) struct sctp_chunk *chunk,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 759) u16 chunk_len)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 760) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 761) enum sctp_xmit retval = SCTP_XMIT_OK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 762) size_t psize, pmtu, maxsize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 763)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 764) /* Don't bundle in this packet if this chunk's auth key doesn't
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 765) * match other chunks already enqueued on this packet. Also,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 766) * don't bundle the chunk with auth key if other chunks in this
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 767) * packet don't have auth key.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 768) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 769) if ((packet->auth && chunk->shkey != packet->auth->shkey) ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 770) (!packet->auth && chunk->shkey &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 771) chunk->chunk_hdr->type != SCTP_CID_AUTH))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 772) return SCTP_XMIT_PMTU_FULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 773)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 774) psize = packet->size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 775) if (packet->transport->asoc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 776) pmtu = packet->transport->asoc->pathmtu;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 777) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 778) pmtu = packet->transport->pathmtu;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 779)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 780) /* Decide if we need to fragment or resubmit later. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 781) if (psize + chunk_len > pmtu) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 782) /* It's OK to fragment at IP level if any one of the following
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 783) * is true:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 784) * 1. The packet is empty (meaning this chunk is greater
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 785) * the MTU)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 786) * 2. The packet doesn't have any data in it yet and data
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 787) * requires authentication.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 788) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 789) if (sctp_packet_empty(packet) ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 790) (!packet->has_data && chunk->auth)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 791) /* We no longer do re-fragmentation.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 792) * Just fragment at the IP layer, if we
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 793) * actually hit this condition
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 794) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 795) packet->ipfragok = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 796) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 797) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 798)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 799) /* Similarly, if this chunk was built before a PMTU
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 800) * reduction, we have to fragment it at IP level now. So
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 801) * if the packet already contains something, we need to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 802) * flush.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 803) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 804) maxsize = pmtu - packet->overhead;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 805) if (packet->auth)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 806) maxsize -= SCTP_PAD4(packet->auth->skb->len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 807) if (chunk_len > maxsize)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 808) retval = SCTP_XMIT_PMTU_FULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 809)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 810) /* It is also okay to fragment if the chunk we are
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 811) * adding is a control chunk, but only if current packet
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 812) * is not a GSO one otherwise it causes fragmentation of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 813) * a large frame. So in this case we allow the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 814) * fragmentation by forcing it to be in a new packet.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 815) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 816) if (!sctp_chunk_is_data(chunk) && packet->has_data)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 817) retval = SCTP_XMIT_PMTU_FULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 818)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 819) if (psize + chunk_len > packet->max_size)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 820) /* Hit GSO/PMTU limit, gotta flush */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 821) retval = SCTP_XMIT_PMTU_FULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 822)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 823) if (!packet->transport->burst_limited &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 824) psize + chunk_len > (packet->transport->cwnd >> 1))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 825) /* Do not allow a single GSO packet to use more
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 826) * than half of cwnd.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 827) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 828) retval = SCTP_XMIT_PMTU_FULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 829)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 830) if (packet->transport->burst_limited &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 831) psize + chunk_len > (packet->transport->burst_limited >> 1))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 832) /* Do not allow a single GSO packet to use more
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 833) * than half of original cwnd.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 834) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 835) retval = SCTP_XMIT_PMTU_FULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 836) /* Otherwise it will fit in the GSO packet */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 837) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 838)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 839) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 840) return retval;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 841) }
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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