/*
* Process event packets targetted at a local endpoint.
*/
void rxrpc_process_local_events(struct rxrpc_local *local)
{
struct sk_buff *skb;
char v;
_enter("");
skb = skb_dequeue(&local->event_queue);
if (skb) {
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
rxrpc_see_skb(skb, rxrpc_skb_rx_seen);
_debug("{%d},{%u}", local->debug_id, sp->hdr.type);
switch (sp->hdr.type) {
case RXRPC_PACKET_TYPE_VERSION:
if (skb_copy_bits(skb, sizeof(struct rxrpc_wire_header),
&v, 1) < 0)
return;
_proto("Rx VERSION { %02x }", v);
if (v == 0)
rxrpc_send_version_request(local, &sp->hdr, skb);
break;
default:
/* Just ignore anything we don't understand */
break;
}
rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
}
_leave("");
}
/*
* connection-level event processor
*/
void rxrpc_process_connection(struct work_struct *work)
{
struct rxrpc_connection *conn =
container_of(work, struct rxrpc_connection, processor);
struct sk_buff *skb;
u32 abort_code = RX_PROTOCOL_ERROR;
int ret;
rxrpc_see_connection(conn);
if (test_and_clear_bit(RXRPC_CONN_EV_CHALLENGE, &conn->events))
rxrpc_secure_connection(conn);
/* Process delayed ACKs whose time has come. */
if (conn->flags & RXRPC_CONN_FINAL_ACK_MASK)
rxrpc_process_delayed_final_acks(conn);
/* go through the conn-level event packets, releasing the ref on this
* connection that each one has when we've finished with it */
while ((skb = skb_dequeue(&conn->rx_queue))) {
rxrpc_see_skb(skb, rxrpc_skb_rx_seen);
ret = rxrpc_process_event(conn, skb, &abort_code);
switch (ret) {
case -EPROTO:
case -EKEYEXPIRED:
case -EKEYREJECTED:
goto protocol_error;
case -ENOMEM:
case -EAGAIN:
goto requeue_and_leave;
case -ECONNABORTED:
default:
rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
break;
}
}
out:
rxrpc_put_connection(conn);
_leave("");
return;
requeue_and_leave:
skb_queue_head(&conn->rx_queue, skb);
goto out;
protocol_error:
if (rxrpc_abort_connection(conn, ret, abort_code) < 0)
goto requeue_and_leave;
rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
goto out;
}
/*
* reject packets through the local endpoint
*/
void rxrpc_reject_packets(struct rxrpc_local *local)
{
struct sockaddr_rxrpc srx;
struct rxrpc_skb_priv *sp;
struct rxrpc_wire_header whdr;
struct sk_buff *skb;
struct msghdr msg;
struct kvec iov[2];
size_t size;
__be32 code;
_enter("%d", local->debug_id);
iov[0].iov_base = &whdr;
iov[0].iov_len = sizeof(whdr);
iov[1].iov_base = &code;
iov[1].iov_len = sizeof(code);
size = sizeof(whdr) + sizeof(code);
msg.msg_name = &srx.transport;
msg.msg_control = NULL;
msg.msg_controllen = 0;
msg.msg_flags = 0;
memset(&whdr, 0, sizeof(whdr));
whdr.type = RXRPC_PACKET_TYPE_ABORT;
while ((skb = skb_dequeue(&local->reject_queue))) {
rxrpc_see_skb(skb, rxrpc_skb_rx_seen);
sp = rxrpc_skb(skb);
if (rxrpc_extract_addr_from_skb(&srx, skb) == 0) {
msg.msg_namelen = srx.transport_len;
code = htonl(skb->priority);
whdr.epoch = htonl(sp->hdr.epoch);
whdr.cid = htonl(sp->hdr.cid);
whdr.callNumber = htonl(sp->hdr.callNumber);
whdr.serviceId = htons(sp->hdr.serviceId);
whdr.flags = sp->hdr.flags;
whdr.flags ^= RXRPC_CLIENT_INITIATED;
whdr.flags &= RXRPC_CLIENT_INITIATED;
kernel_sendmsg(local->socket, &msg, iov, 2, size);
}
rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
}
_leave("");
}
/*
* Discard a packet we've used up and advance the Rx window by one.
*/
static void rxrpc_rotate_rx_window(struct rxrpc_call *call)
{
struct rxrpc_skb_priv *sp;
struct sk_buff *skb;
rxrpc_serial_t serial;
rxrpc_seq_t hard_ack, top;
u8 flags;
int ix;
_enter("%d", call->debug_id);
hard_ack = call->rx_hard_ack;
top = smp_load_acquire(&call->rx_top);
ASSERT(before(hard_ack, top));
hard_ack++;
ix = hard_ack & RXRPC_RXTX_BUFF_MASK;
skb = call->rxtx_buffer[ix];
rxrpc_see_skb(skb, rxrpc_skb_rx_rotated);
sp = rxrpc_skb(skb);
flags = sp->hdr.flags;
serial = sp->hdr.serial;
if (call->rxtx_annotations[ix] & RXRPC_RX_ANNO_JUMBO)
serial += (call->rxtx_annotations[ix] & RXRPC_RX_ANNO_JUMBO) - 1;
call->rxtx_buffer[ix] = NULL;
call->rxtx_annotations[ix] = 0;
/* Barrier against rxrpc_input_data(). */
smp_store_release(&call->rx_hard_ack, hard_ack);
rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
_debug("%u,%u,%02x", hard_ack, top, flags);
trace_rxrpc_receive(call, rxrpc_receive_rotate, serial, hard_ack);
if (flags & RXRPC_LAST_PACKET) {
rxrpc_end_rx_phase(call, serial);
} else {
/* Check to see if there's an ACK that needs sending. */
if (after_eq(hard_ack, call->ackr_consumed + 2) ||
after_eq(top, call->ackr_seen + 2) ||
(hard_ack == top && after(hard_ack, call->ackr_consumed)))
rxrpc_propose_ACK(call, RXRPC_ACK_DELAY, 0, serial,
true, false,
rxrpc_propose_ack_rotate_rx);
if (call->ackr_reason)
rxrpc_send_call_packet(call, RXRPC_PACKET_TYPE_ACK);
}
}
/*
* Perform retransmission of NAK'd and unack'd packets.
*/
static void rxrpc_resend(struct rxrpc_call *call, ktime_t now)
{
struct rxrpc_skb_priv *sp;
struct sk_buff *skb;
rxrpc_seq_t cursor, seq, top;
ktime_t max_age, oldest, ack_ts;
int ix;
u8 annotation, anno_type, retrans = 0, unacked = 0;
_enter("{%d,%d}", call->tx_hard_ack, call->tx_top);
max_age = ktime_sub_ms(now, rxrpc_resend_timeout);
spin_lock_bh(&call->lock);
cursor = call->tx_hard_ack;
top = call->tx_top;
ASSERT(before_eq(cursor, top));
if (cursor == top)
goto out_unlock;
/* Scan the packet list without dropping the lock and decide which of
* the packets in the Tx buffer we're going to resend and what the new
* resend timeout will be.
*/
oldest = now;
for (seq = cursor + 1; before_eq(seq, top); seq++) {
ix = seq & RXRPC_RXTX_BUFF_MASK;
annotation = call->rxtx_annotations[ix];
anno_type = annotation & RXRPC_TX_ANNO_MASK;
annotation &= ~RXRPC_TX_ANNO_MASK;
if (anno_type == RXRPC_TX_ANNO_ACK)
continue;
skb = call->rxtx_buffer[ix];
rxrpc_see_skb(skb, rxrpc_skb_tx_seen);
sp = rxrpc_skb(skb);
if (anno_type == RXRPC_TX_ANNO_UNACK) {
if (ktime_after(skb->tstamp, max_age)) {
if (ktime_before(skb->tstamp, oldest))
oldest = skb->tstamp;
continue;
}
if (!(annotation & RXRPC_TX_ANNO_RESENT))
unacked++;
}
/* Okay, we need to retransmit a packet. */
call->rxtx_annotations[ix] = RXRPC_TX_ANNO_RETRANS | annotation;
retrans++;
trace_rxrpc_retransmit(call, seq, annotation | anno_type,
ktime_to_ns(ktime_sub(skb->tstamp, max_age)));
}
call->resend_at = ktime_add_ms(oldest, rxrpc_resend_timeout);
if (unacked)
rxrpc_congestion_timeout(call);
/* If there was nothing that needed retransmission then it's likely
* that an ACK got lost somewhere. Send a ping to find out instead of
* retransmitting data.
*/
if (!retrans) {
rxrpc_set_timer(call, rxrpc_timer_set_for_resend, now);
spin_unlock_bh(&call->lock);
ack_ts = ktime_sub(now, call->acks_latest_ts);
if (ktime_to_ns(ack_ts) < call->peer->rtt)
goto out;
rxrpc_propose_ACK(call, RXRPC_ACK_PING, 0, 0, true, false,
rxrpc_propose_ack_ping_for_lost_ack);
rxrpc_send_ack_packet(call, true);
goto out;
}
/* Now go through the Tx window and perform the retransmissions. We
* have to drop the lock for each send. If an ACK comes in whilst the
* lock is dropped, it may clear some of the retransmission markers for
* packets that it soft-ACKs.
*/
for (seq = cursor + 1; before_eq(seq, top); seq++) {
ix = seq & RXRPC_RXTX_BUFF_MASK;
annotation = call->rxtx_annotations[ix];
anno_type = annotation & RXRPC_TX_ANNO_MASK;
if (anno_type != RXRPC_TX_ANNO_RETRANS)
continue;
skb = call->rxtx_buffer[ix];
rxrpc_get_skb(skb, rxrpc_skb_tx_got);
spin_unlock_bh(&call->lock);
if (rxrpc_send_data_packet(call, skb, true) < 0) {
rxrpc_free_skb(skb, rxrpc_skb_tx_freed);
return;
}
if (rxrpc_is_client_call(call))
rxrpc_expose_client_call(call);
rxrpc_free_skb(skb, rxrpc_skb_tx_freed);
spin_lock_bh(&call->lock);
/* We need to clear the retransmit state, but there are two
* things we need to be aware of: A new ACK/NAK might have been
* received and the packet might have been hard-ACK'd (in which
* case it will no longer be in the buffer).
*/
if (after(seq, call->tx_hard_ack)) {
annotation = call->rxtx_annotations[ix];
anno_type = annotation & RXRPC_TX_ANNO_MASK;
if (anno_type == RXRPC_TX_ANNO_RETRANS ||
anno_type == RXRPC_TX_ANNO_NAK) {
annotation &= ~RXRPC_TX_ANNO_MASK;
annotation |= RXRPC_TX_ANNO_UNACK;
}
annotation |= RXRPC_TX_ANNO_RESENT;
call->rxtx_annotations[ix] = annotation;
}
if (after(call->tx_hard_ack, seq))
seq = call->tx_hard_ack;
}
out_unlock:
spin_unlock_bh(&call->lock);
out:
_leave("");
}
/*
* Deliver messages to a call. This keeps processing packets until the buffer
* is filled and we find either more DATA (returns 0) or the end of the DATA
* (returns 1). If more packets are required, it returns -EAGAIN.
*/
static int rxrpc_recvmsg_data(struct socket *sock, struct rxrpc_call *call,
struct msghdr *msg, struct iov_iter *iter,
size_t len, int flags, size_t *_offset)
{
struct rxrpc_skb_priv *sp;
struct sk_buff *skb;
rxrpc_seq_t hard_ack, top, seq;
size_t remain;
bool last;
unsigned int rx_pkt_offset, rx_pkt_len;
int ix, copy, ret = -EAGAIN, ret2;
rx_pkt_offset = call->rx_pkt_offset;
rx_pkt_len = call->rx_pkt_len;
if (call->state >= RXRPC_CALL_SERVER_ACK_REQUEST) {
seq = call->rx_hard_ack;
ret = 1;
goto done;
}
/* Barriers against rxrpc_input_data(). */
hard_ack = call->rx_hard_ack;
top = smp_load_acquire(&call->rx_top);
for (seq = hard_ack + 1; before_eq(seq, top); seq++) {
ix = seq & RXRPC_RXTX_BUFF_MASK;
skb = call->rxtx_buffer[ix];
if (!skb) {
trace_rxrpc_recvmsg(call, rxrpc_recvmsg_hole, seq,
rx_pkt_offset, rx_pkt_len, 0);
break;
}
smp_rmb();
rxrpc_see_skb(skb, rxrpc_skb_rx_seen);
sp = rxrpc_skb(skb);
if (!(flags & MSG_PEEK))
trace_rxrpc_receive(call, rxrpc_receive_front,
sp->hdr.serial, seq);
if (msg)
sock_recv_timestamp(msg, sock->sk, skb);
if (rx_pkt_offset == 0) {
ret2 = rxrpc_locate_data(call, skb,
&call->rxtx_annotations[ix],
&rx_pkt_offset, &rx_pkt_len);
trace_rxrpc_recvmsg(call, rxrpc_recvmsg_next, seq,
rx_pkt_offset, rx_pkt_len, ret2);
if (ret2 < 0) {
ret = ret2;
goto out;
}
} else {
trace_rxrpc_recvmsg(call, rxrpc_recvmsg_cont, seq,
rx_pkt_offset, rx_pkt_len, 0);
}
/* We have to handle short, empty and used-up DATA packets. */
remain = len - *_offset;
copy = rx_pkt_len;
if (copy > remain)
copy = remain;
if (copy > 0) {
ret2 = skb_copy_datagram_iter(skb, rx_pkt_offset, iter,
copy);
if (ret2 < 0) {
ret = ret2;
goto out;
}
/* handle piecemeal consumption of data packets */
rx_pkt_offset += copy;
rx_pkt_len -= copy;
*_offset += copy;
}
if (rx_pkt_len > 0) {
trace_rxrpc_recvmsg(call, rxrpc_recvmsg_full, seq,
rx_pkt_offset, rx_pkt_len, 0);
ASSERTCMP(*_offset, ==, len);
ret = 0;
break;
}
/* The whole packet has been transferred. */
last = sp->hdr.flags & RXRPC_LAST_PACKET;
if (!(flags & MSG_PEEK))
rxrpc_rotate_rx_window(call);
rx_pkt_offset = 0;
rx_pkt_len = 0;
if (last) {
ASSERTCMP(seq, ==, READ_ONCE(call->rx_top));
ret = 1;
goto out;
}
}
