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Diffstat (limited to 'net/sctp/output.c')
-rw-r--r--net/sctp/output.c363
1 files changed, 249 insertions, 114 deletions
diff --git a/net/sctp/output.c b/net/sctp/output.c
index 9844fe573029..60499a69179d 100644
--- a/net/sctp/output.c
+++ b/net/sctp/output.c
@@ -84,18 +84,42 @@ static void sctp_packet_reset(struct sctp_packet *packet)
struct sctp_packet *sctp_packet_config(struct sctp_packet *packet,
__u32 vtag, int ecn_capable)
{
- struct sctp_chunk *chunk = NULL;
+ struct sctp_transport *tp = packet->transport;
+ struct sctp_association *asoc = tp->asoc;
pr_debug("%s: packet:%p vtag:0x%x\n", __func__, packet, vtag);
packet->vtag = vtag;
+ if (asoc && tp->dst) {
+ struct sock *sk = asoc->base.sk;
+
+ rcu_read_lock();
+ if (__sk_dst_get(sk) != tp->dst) {
+ dst_hold(tp->dst);
+ sk_setup_caps(sk, tp->dst);
+ }
+
+ if (sk_can_gso(sk)) {
+ struct net_device *dev = tp->dst->dev;
+
+ packet->max_size = dev->gso_max_size;
+ } else {
+ packet->max_size = asoc->pathmtu;
+ }
+ rcu_read_unlock();
+
+ } else {
+ packet->max_size = tp->pathmtu;
+ }
+
if (ecn_capable && sctp_packet_empty(packet)) {
- chunk = sctp_get_ecne_prepend(packet->transport->asoc);
+ struct sctp_chunk *chunk;
/* If there a is a prepend chunk stick it on the list before
* any other chunks get appended.
*/
+ chunk = sctp_get_ecne_prepend(asoc);
if (chunk)
sctp_packet_append_chunk(packet, chunk);
}
@@ -381,12 +405,15 @@ int sctp_packet_transmit(struct sctp_packet *packet, gfp_t gfp)
struct sctp_transport *tp = packet->transport;
struct sctp_association *asoc = tp->asoc;
struct sctphdr *sh;
- struct sk_buff *nskb;
+ struct sk_buff *nskb = NULL, *head = NULL;
struct sctp_chunk *chunk, *tmp;
struct sock *sk;
int err = 0;
int padding; /* How much padding do we need? */
+ int pkt_size;
__u8 has_data = 0;
+ int gso = 0;
+ int pktcount = 0;
struct dst_entry *dst;
unsigned char *auth = NULL; /* pointer to auth in skb data */
@@ -400,18 +427,37 @@ int sctp_packet_transmit(struct sctp_packet *packet, gfp_t gfp)
chunk = list_entry(packet->chunk_list.next, struct sctp_chunk, list);
sk = chunk->skb->sk;
- /* Allocate the new skb. */
- nskb = alloc_skb(packet->size + MAX_HEADER, gfp);
- if (!nskb)
+ /* Allocate the head skb, or main one if not in GSO */
+ if (packet->size > tp->pathmtu && !packet->ipfragok) {
+ if (sk_can_gso(sk)) {
+ gso = 1;
+ pkt_size = packet->overhead;
+ } else {
+ /* If this happens, we trash this packet and try
+ * to build a new one, hopefully correct this
+ * time. Application may notice this error.
+ */
+ pr_err_once("Trying to GSO but underlying device doesn't support it.");
+ goto nomem;
+ }
+ } else {
+ pkt_size = packet->size;
+ }
+ head = alloc_skb(pkt_size + MAX_HEADER, gfp);
+ if (!head)
goto nomem;
+ if (gso) {
+ NAPI_GRO_CB(head)->last = head;
+ skb_shinfo(head)->gso_type = sk->sk_gso_type;
+ }
/* Make sure the outbound skb has enough header room reserved. */
- skb_reserve(nskb, packet->overhead + MAX_HEADER);
+ skb_reserve(head, packet->overhead + MAX_HEADER);
/* Set the owning socket so that we know where to get the
* destination IP address.
*/
- sctp_packet_set_owner_w(nskb, sk);
+ sctp_packet_set_owner_w(head, sk);
if (!sctp_transport_dst_check(tp)) {
sctp_transport_route(tp, NULL, sctp_sk(sk));
@@ -422,11 +468,11 @@ int sctp_packet_transmit(struct sctp_packet *packet, gfp_t gfp)
dst = dst_clone(tp->dst);
if (!dst)
goto no_route;
- skb_dst_set(nskb, dst);
+ skb_dst_set(head, dst);
/* Build the SCTP header. */
- sh = (struct sctphdr *)skb_push(nskb, sizeof(struct sctphdr));
- skb_reset_transport_header(nskb);
+ sh = (struct sctphdr *)skb_push(head, sizeof(struct sctphdr));
+ skb_reset_transport_header(head);
sh->source = htons(packet->source_port);
sh->dest = htons(packet->destination_port);
@@ -441,90 +487,133 @@ int sctp_packet_transmit(struct sctp_packet *packet, gfp_t gfp)
sh->vtag = htonl(packet->vtag);
sh->checksum = 0;
- /**
- * 6.10 Bundling
- *
- * An endpoint bundles chunks by simply including multiple
- * chunks in one outbound SCTP packet. ...
- */
-
- /**
- * 3.2 Chunk Field Descriptions
- *
- * The total length of a chunk (including Type, Length and
- * Value fields) MUST be a multiple of 4 bytes. If the length
- * of the chunk is not a multiple of 4 bytes, the sender MUST
- * pad the chunk with all zero bytes and this padding is not
- * included in the chunk length field. The sender should
- * never pad with more than 3 bytes.
- *
- * [This whole comment explains WORD_ROUND() below.]
- */
-
pr_debug("***sctp_transmit_packet***\n");
- list_for_each_entry_safe(chunk, tmp, &packet->chunk_list, list) {
- list_del_init(&chunk->list);
- if (sctp_chunk_is_data(chunk)) {
- /* 6.3.1 C4) When data is in flight and when allowed
- * by rule C5, a new RTT measurement MUST be made each
- * round trip. Furthermore, new RTT measurements
- * SHOULD be made no more than once per round-trip
- * for a given destination transport address.
- */
+ do {
+ /* Set up convenience variables... */
+ chunk = list_entry(packet->chunk_list.next, struct sctp_chunk, list);
+ pktcount++;
- if (!chunk->resent && !tp->rto_pending) {
- chunk->rtt_in_progress = 1;
- tp->rto_pending = 1;
+ /* Calculate packet size, so it fits in PMTU. Leave
+ * other chunks for the next packets.
+ */
+ if (gso) {
+ pkt_size = packet->overhead;
+ list_for_each_entry(chunk, &packet->chunk_list, list) {
+ int padded = WORD_ROUND(chunk->skb->len);
+
+ if (pkt_size + padded > tp->pathmtu)
+ break;
+ pkt_size += padded;
}
- has_data = 1;
- }
+ /* Allocate a new skb. */
+ nskb = alloc_skb(pkt_size + MAX_HEADER, gfp);
+ if (!nskb)
+ goto nomem;
- padding = WORD_ROUND(chunk->skb->len) - chunk->skb->len;
- if (padding)
- memset(skb_put(chunk->skb, padding), 0, padding);
+ /* Make sure the outbound skb has enough header
+ * room reserved.
+ */
+ skb_reserve(nskb, packet->overhead + MAX_HEADER);
+ } else {
+ nskb = head;
+ }
- /* if this is the auth chunk that we are adding,
- * store pointer where it will be added and put
- * the auth into the packet.
+ /**
+ * 3.2 Chunk Field Descriptions
+ *
+ * The total length of a chunk (including Type, Length and
+ * Value fields) MUST be a multiple of 4 bytes. If the length
+ * of the chunk is not a multiple of 4 bytes, the sender MUST
+ * pad the chunk with all zero bytes and this padding is not
+ * included in the chunk length field. The sender should
+ * never pad with more than 3 bytes.
+ *
+ * [This whole comment explains WORD_ROUND() below.]
*/
- if (chunk == packet->auth)
- auth = skb_tail_pointer(nskb);
- memcpy(skb_put(nskb, chunk->skb->len),
+ pkt_size -= packet->overhead;
+ list_for_each_entry_safe(chunk, tmp, &packet->chunk_list, list) {
+ list_del_init(&chunk->list);
+ if (sctp_chunk_is_data(chunk)) {
+ /* 6.3.1 C4) When data is in flight and when allowed
+ * by rule C5, a new RTT measurement MUST be made each
+ * round trip. Furthermore, new RTT measurements
+ * SHOULD be made no more than once per round-trip
+ * for a given destination transport address.
+ */
+
+ if (!chunk->resent && !tp->rto_pending) {
+ chunk->rtt_in_progress = 1;
+ tp->rto_pending = 1;
+ }
+
+ has_data = 1;
+ }
+
+ padding = WORD_ROUND(chunk->skb->len) - chunk->skb->len;
+ if (padding)
+ memset(skb_put(chunk->skb, padding), 0, padding);
+
+ /* if this is the auth chunk that we are adding,
+ * store pointer where it will be added and put
+ * the auth into the packet.
+ */
+ if (chunk == packet->auth)
+ auth = skb_tail_pointer(nskb);
+
+ memcpy(skb_put(nskb, chunk->skb->len),
chunk->skb->data, chunk->skb->len);
- pr_debug("*** Chunk:%p[%s] %s 0x%x, length:%d, chunk->skb->len:%d, "
- "rtt_in_progress:%d\n", chunk,
- sctp_cname(SCTP_ST_CHUNK(chunk->chunk_hdr->type)),
- chunk->has_tsn ? "TSN" : "No TSN",
- chunk->has_tsn ? ntohl(chunk->subh.data_hdr->tsn) : 0,
- ntohs(chunk->chunk_hdr->length), chunk->skb->len,
- chunk->rtt_in_progress);
-
- /*
- * If this is a control chunk, this is our last
- * reference. Free data chunks after they've been
- * acknowledged or have failed.
- */
- if (!sctp_chunk_is_data(chunk))
- sctp_chunk_free(chunk);
- }
+ pr_debug("*** Chunk:%p[%s] %s 0x%x, length:%d, chunk->skb->len:%d, rtt_in_progress:%d\n",
+ chunk,
+ sctp_cname(SCTP_ST_CHUNK(chunk->chunk_hdr->type)),
+ chunk->has_tsn ? "TSN" : "No TSN",
+ chunk->has_tsn ? ntohl(chunk->subh.data_hdr->tsn) : 0,
+ ntohs(chunk->chunk_hdr->length), chunk->skb->len,
+ chunk->rtt_in_progress);
+
+ /* If this is a control chunk, this is our last
+ * reference. Free data chunks after they've been
+ * acknowledged or have failed.
+ * Re-queue auth chunks if needed.
+ */
+ pkt_size -= WORD_ROUND(chunk->skb->len);
- /* SCTP-AUTH, Section 6.2
- * The sender MUST calculate the MAC as described in RFC2104 [2]
- * using the hash function H as described by the MAC Identifier and
- * the shared association key K based on the endpoint pair shared key
- * described by the shared key identifier. The 'data' used for the
- * computation of the AUTH-chunk is given by the AUTH chunk with its
- * HMAC field set to zero (as shown in Figure 6) followed by all
- * chunks that are placed after the AUTH chunk in the SCTP packet.
- */
- if (auth)
- sctp_auth_calculate_hmac(asoc, nskb,
- (struct sctp_auth_chunk *)auth,
- gfp);
+ if (chunk == packet->auth && !list_empty(&packet->chunk_list))
+ list_add(&chunk->list, &packet->chunk_list);
+ else if (!sctp_chunk_is_data(chunk))
+ sctp_chunk_free(chunk);
+
+ if (!pkt_size)
+ break;
+ }
+
+ /* SCTP-AUTH, Section 6.2
+ * The sender MUST calculate the MAC as described in RFC2104 [2]
+ * using the hash function H as described by the MAC Identifier and
+ * the shared association key K based on the endpoint pair shared key
+ * described by the shared key identifier. The 'data' used for the
+ * computation of the AUTH-chunk is given by the AUTH chunk with its
+ * HMAC field set to zero (as shown in Figure 6) followed by all
+ * chunks that are placed after the AUTH chunk in the SCTP packet.
+ */
+ if (auth)
+ sctp_auth_calculate_hmac(asoc, nskb,
+ (struct sctp_auth_chunk *)auth,
+ gfp);
+
+ if (!gso)
+ break;
+
+ if (skb_gro_receive(&head, nskb))
+ goto nomem;
+ nskb = NULL;
+ if (WARN_ON_ONCE(skb_shinfo(head)->gso_segs >=
+ sk->sk_gso_max_segs))
+ goto nomem;
+ } while (!list_empty(&packet->chunk_list));
/* 2) Calculate the Adler-32 checksum of the whole packet,
* including the SCTP common header and all the
@@ -532,16 +621,18 @@ int sctp_packet_transmit(struct sctp_packet *packet, gfp_t gfp)
*
* Note: Adler-32 is no longer applicable, as has been replaced
* by CRC32-C as described in <draft-ietf-tsvwg-sctpcsum-02.txt>.
+ *
+ * If it's a GSO packet, it's postponed to sctp_skb_segment.
*/
- if (!sctp_checksum_disable) {
- if (!(dst->dev->features & NETIF_F_SCTP_CRC) ||
- (dst_xfrm(dst) != NULL) || packet->ipfragok) {
- sh->checksum = sctp_compute_cksum(nskb, 0);
+ if (!sctp_checksum_disable || gso) {
+ if (!gso && (!(dst->dev->features & NETIF_F_SCTP_CRC) ||
+ dst_xfrm(dst) || packet->ipfragok)) {
+ sh->checksum = sctp_compute_cksum(head, 0);
} else {
/* no need to seed pseudo checksum for SCTP */
- nskb->ip_summed = CHECKSUM_PARTIAL;
- nskb->csum_start = skb_transport_header(nskb) - nskb->head;
- nskb->csum_offset = offsetof(struct sctphdr, checksum);
+ head->ip_summed = CHECKSUM_PARTIAL;
+ head->csum_start = skb_transport_header(head) - head->head;
+ head->csum_offset = offsetof(struct sctphdr, checksum);
}
}
@@ -557,7 +648,7 @@ int sctp_packet_transmit(struct sctp_packet *packet, gfp_t gfp)
* Note: The works for IPv6 layer checks this bit too later
* in transmission. See IP6_ECN_flow_xmit().
*/
- tp->af_specific->ecn_capable(nskb->sk);
+ tp->af_specific->ecn_capable(sk);
/* Set up the IP options. */
/* BUG: not implemented
@@ -566,7 +657,7 @@ int sctp_packet_transmit(struct sctp_packet *packet, gfp_t gfp)
/* Dump that on IP! */
if (asoc) {
- asoc->stats.opackets++;
+ asoc->stats.opackets += pktcount;
if (asoc->peer.last_sent_to != tp)
/* Considering the multiple CPU scenario, this is a
* "correcter" place for last_sent_to. --xguo
@@ -589,16 +680,36 @@ int sctp_packet_transmit(struct sctp_packet *packet, gfp_t gfp)
}
}
- pr_debug("***sctp_transmit_packet*** skb->len:%d\n", nskb->len);
+ pr_debug("***sctp_transmit_packet*** skb->len:%d\n", head->len);
+
+ if (gso) {
+ /* Cleanup our debris for IP stacks */
+ memset(head->cb, 0, max(sizeof(struct inet_skb_parm),
+ sizeof(struct inet6_skb_parm)));
- nskb->ignore_df = packet->ipfragok;
- tp->af_specific->sctp_xmit(nskb, tp);
+ skb_shinfo(head)->gso_segs = pktcount;
+ skb_shinfo(head)->gso_size = GSO_BY_FRAGS;
+
+ /* We have to refresh this in case we are xmiting to
+ * more than one transport at a time
+ */
+ rcu_read_lock();
+ if (__sk_dst_get(sk) != tp->dst) {
+ dst_hold(tp->dst);
+ sk_setup_caps(sk, tp->dst);
+ }
+ rcu_read_unlock();
+ }
+ head->ignore_df = packet->ipfragok;
+ tp->af_specific->sctp_xmit(head, tp);
out:
sctp_packet_reset(packet);
return err;
no_route:
- kfree_skb(nskb);
+ kfree_skb(head);
+ if (nskb != head)
+ kfree_skb(nskb);
if (asoc)
IP_INC_STATS(sock_net(asoc->base.sk), IPSTATS_MIB_OUTNOROUTES);
@@ -751,39 +862,63 @@ static sctp_xmit_t sctp_packet_will_fit(struct sctp_packet *packet,
struct sctp_chunk *chunk,
u16 chunk_len)
{
- size_t psize;
- size_t pmtu;
- int too_big;
+ size_t psize, pmtu;
sctp_xmit_t retval = SCTP_XMIT_OK;
psize = packet->size;
- pmtu = ((packet->transport->asoc) ?
- (packet->transport->asoc->pathmtu) :
- (packet->transport->pathmtu));
-
- too_big = (psize + chunk_len > pmtu);
+ if (packet->transport->asoc)
+ pmtu = packet->transport->asoc->pathmtu;
+ else
+ pmtu = packet->transport->pathmtu;
/* Decide if we need to fragment or resubmit later. */
- if (too_big) {
- /* It's OK to fragmet at IP level if any one of the following
+ if (psize + chunk_len > pmtu) {
+ /* It's OK to fragment at IP level if any one of the following
* is true:
- * 1. The packet is empty (meaning this chunk is greater
- * the MTU)
- * 2. The chunk we are adding is a control chunk
- * 3. The packet doesn't have any data in it yet and data
- * requires authentication.
+ * 1. The packet is empty (meaning this chunk is greater
+ * the MTU)
+ * 2. The packet doesn't have any data in it yet and data
+ * requires authentication.
*/
- if (sctp_packet_empty(packet) || !sctp_chunk_is_data(chunk) ||
+ if (sctp_packet_empty(packet) ||
(!packet->has_data && chunk->auth)) {
/* We no longer do re-fragmentation.
* Just fragment at the IP layer, if we
* actually hit this condition
*/
packet->ipfragok = 1;
- } else {
- retval = SCTP_XMIT_PMTU_FULL;
+ goto out;
}
+
+ /* It is also okay to fragment if the chunk we are
+ * adding is a control chunk, but only if current packet
+ * is not a GSO one otherwise it causes fragmentation of
+ * a large frame. So in this case we allow the
+ * fragmentation by forcing it to be in a new packet.
+ */
+ if (!sctp_chunk_is_data(chunk) && packet->has_data)
+ retval = SCTP_XMIT_PMTU_FULL;
+
+ if (psize + chunk_len > packet->max_size)
+ /* Hit GSO/PMTU limit, gotta flush */
+ retval = SCTP_XMIT_PMTU_FULL;
+
+ if (!packet->transport->burst_limited &&
+ psize + chunk_len > (packet->transport->cwnd >> 1))
+ /* Do not allow a single GSO packet to use more
+ * than half of cwnd.
+ */
+ retval = SCTP_XMIT_PMTU_FULL;
+
+ if (packet->transport->burst_limited &&
+ psize + chunk_len > (packet->transport->burst_limited >> 1))
+ /* Do not allow a single GSO packet to use more
+ * than half of original cwnd.
+ */
+ retval = SCTP_XMIT_PMTU_FULL;
+ /* Otherwise it will fit in the GSO packet */
}
+out:
return retval;
}
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-14 03:49:02 +0300