// SPDX-License-Identifier: GPL-2.0-or-later
/* connection-level event handling
*
* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
* Written by David Howells ([email protected])
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/net.h>
#include <linux/skbuff.h>
#include <linux/errqueue.h>
#include <net/sock.h>
#include <net/af_rxrpc.h>
#include <net/ip.h>
#include "ar-internal.h"
/*
* Set the completion state on an aborted connection.
*/
static bool rxrpc_set_conn_aborted(struct rxrpc_connection *conn, struct sk_buff *skb,
s32 abort_code, int err,
enum rxrpc_call_completion compl)
{
bool aborted = false;
if (conn->state != RXRPC_CONN_ABORTED) {
spin_lock(&conn->state_lock);
if (conn->state != RXRPC_CONN_ABORTED) {
conn->abort_code = abort_code;
conn->error = err;
conn->completion = compl;
/* Order the abort info before the state change. */
smp_store_release(&conn->state, RXRPC_CONN_ABORTED);
set_bit(RXRPC_CONN_DONT_REUSE, &conn->flags);
set_bit(RXRPC_CONN_EV_ABORT_CALLS, &conn->events);
aborted = true;
}
spin_unlock(&conn->state_lock);
}
return aborted;
}
/*
* Mark a socket buffer to indicate that the connection it's on should be aborted.
*/
int rxrpc_abort_conn(struct rxrpc_connection *conn, struct sk_buff *skb,
s32 abort_code, int err, enum rxrpc_abort_reason why)
{
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
if (rxrpc_set_conn_aborted(conn, skb, abort_code, err,
RXRPC_CALL_LOCALLY_ABORTED)) {
trace_rxrpc_abort(0, why, sp->hdr.cid, sp->hdr.callNumber,
sp->hdr.seq, abort_code, err);
rxrpc_poke_conn(conn, rxrpc_conn_get_poke_abort);
}
return -EPROTO;
}
/*
* Mark a connection as being remotely aborted.
*/
static bool rxrpc_input_conn_abort(struct rxrpc_connection *conn,
struct sk_buff *skb)
{
return rxrpc_set_conn_aborted(conn, skb, skb->priority, -ECONNABORTED,
RXRPC_CALL_REMOTELY_ABORTED);
}
/*
* Retransmit terminal ACK or ABORT of the previous call.
*/
void rxrpc_conn_retransmit_call(struct rxrpc_connection *conn,
struct sk_buff *skb,
unsigned int channel)
{
struct rxrpc_skb_priv *sp = skb ? rxrpc_skb(skb) : NULL;
struct rxrpc_channel *chan;
struct msghdr msg;
struct kvec iov[3];
struct {
struct rxrpc_wire_header whdr;
union {
__be32 abort_code;
struct rxrpc_ackpacket ack;
};
} __attribute__((packed)) pkt;
struct rxrpc_acktrailer trailer;
size_t len;
int ret, ioc;
u32 serial, mtu, call_id, padding;
_enter("%d", conn->debug_id);
if (sp && sp->hdr.type == RXRPC_PACKET_TYPE_ACK) {
if (skb_copy_bits(skb, sizeof(struct rxrpc_wire_header),
&pkt.ack, sizeof(pkt.ack)) < 0)
return;
if (pkt.ack.reason == RXRPC_ACK_PING_RESPONSE)
return;
}
chan = &conn->channels[channel];
/* If the last call got moved on whilst we were waiting to run, just
* ignore this packet.
*/
call_id = chan->last_call;
if (skb && call_id != sp->hdr.callNumber)
return;
msg.msg_name = &conn->peer->srx.transport;
msg.msg_namelen = conn->peer->srx.transport_len;
msg.msg_control = NULL;
msg.msg_controllen = 0;
msg.msg_flags = 0;
iov[0].iov_base = &pkt;
iov[0].iov_len = sizeof(pkt.whdr);
iov[1].iov_base = &padding;
iov[1].iov_len = 3;
iov[2].iov_base = &trailer;
iov[2].iov_len = sizeof(trailer);
serial = rxrpc_get_next_serial(conn);
pkt.whdr.epoch = htonl(conn->proto.epoch);
pkt.whdr.cid = htonl(conn->proto.cid | channel);
pkt.whdr.callNumber = htonl(call_id);
pkt.whdr.serial = htonl(serial);
pkt.whdr.seq = 0;
pkt.whdr.type = chan->last_type;
pkt.whdr.flags = conn->out_clientflag;
pkt.whdr.userStatus = 0;
pkt.whdr.securityIndex = conn->security_ix;
pkt.whdr._rsvd = 0;
pkt.whdr.serviceId = htons(conn->service_id);
len = sizeof(pkt.whdr);
switch (chan->last_type) {
case RXRPC_PACKET_TYPE_ABORT:
pkt.abort_code = htonl(chan->last_abort);
iov[0].iov_len += sizeof(pkt.abort_code);
len += sizeof(pkt.abort_code);
ioc = 1;
break;
case RXRPC_PACKET_TYPE_ACK:
mtu = conn->peer->if_mtu;
mtu -= conn->peer->hdrsize;
pkt.ack.bufferSpace = 0;
pkt.ack.maxSkew = htons(skb ? skb->priority : 0);
pkt.ack.firstPacket = htonl(chan->last_seq + 1);
pkt.ack.previousPacket = htonl(chan->last_seq);
pkt.ack.serial = htonl(skb ? sp->hdr.serial : 0);
pkt.ack.reason = skb ? RXRPC_ACK_DUPLICATE : RXRPC_ACK_IDLE;
pkt.ack.nAcks = 0;
trailer.maxMTU = htonl(rxrpc_rx_mtu);
trailer.ifMTU = htonl(mtu);
trailer.rwind = htonl(rxrpc_rx_window_size);
trailer.jumbo_max = htonl(rxrpc_rx_jumbo_max);
pkt.whdr.flags |= RXRPC_SLOW_START_OK;
padding = 0;
iov[0].iov_len += sizeof(pkt.ack);
len += sizeof(pkt.ack) + 3 + sizeof(trailer);
ioc = 3;
trace_rxrpc_tx_ack(chan->call_debug_id, serial,
ntohl(pkt.ack.firstPacket),
ntohl(pkt.ack.serial),
pkt.ack.reason, 0, rxrpc_rx_window_size);
break;
default:
return;
}
ret = kernel_sendmsg(conn->local->socket, &msg, iov, ioc, len);
conn->peer->last_tx_at = ktime_get_seconds();
if (ret < 0)
trace_rxrpc_tx_fail(chan->call_debug_id, serial, ret,
rxrpc_tx_point_call_final_resend);
else
trace_rxrpc_tx_packet(chan->call_debug_id, &pkt.whdr,
rxrpc_tx_point_call_final_resend);
_leave("");
}
/*
* pass a connection-level abort onto all calls on that connection
*/
static void rxrpc_abort_calls(struct rxrpc_connection *conn)
{
struct rxrpc_call *call;
int i;
_enter("{%d},%x", conn->debug_id, conn->abort_code);
for (i = 0; i < RXRPC_MAXCALLS; i++) {
call = conn->channels[i].call;
if (call)
rxrpc_set_call_completion(call,
conn->completion,
conn->abort_code,
conn->error);
}
_leave("");
}
/*
* mark a call as being on a now-secured channel
* - must be called with BH's disabled.
*/
static void rxrpc_call_is_secure(struct rxrpc_call *call)
{
if (call && __rxrpc_call_state(call) == RXRPC_CALL_SERVER_SECURING) {
rxrpc_set_call_state(call, RXRPC_CALL_SERVER_RECV_REQUEST);
rxrpc_notify_socket(call);
}
}
/*
* connection-level Rx packet processor
*/
static int rxrpc_process_event(struct rxrpc_connection *conn,
struct sk_buff *skb)
{
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
int ret;
if (conn->state == RXRPC_CONN_ABORTED)
return -ECONNABORTED;
_enter("{%d},{%u,%%%u},", conn->debug_id, sp->hdr.type, sp->hdr.serial);
switch (sp->hdr.type) {
case RXRPC_PACKET_TYPE_CHALLENGE:
return conn->security->respond_to_challenge(conn, skb);
case RXRPC_PACKET_TYPE_RESPONSE:
ret = conn->security->verify_response(conn, skb);
if (ret < 0)
return ret;
ret = conn->security->init_connection_security(
conn, conn->key->payload.data[0]);
if (ret < 0)
return ret;
spin_lock(&conn->state_lock);
if (conn->state == RXRPC_CONN_SERVICE_CHALLENGING)
conn->state = RXRPC_CONN_SERVICE;
spin_unlock(&conn->state_lock);
if (conn->state == RXRPC_CONN_SERVICE) {
/* Offload call state flipping to the I/O thread. As
* we've already received the packet, put it on the
* front of the queue.
*/
skb->mark = RXRPC_SKB_MARK_SERVICE_CONN_SECURED;
rxrpc_get_skb(skb, rxrpc_skb_get_conn_secured);
skb_queue_head(&conn->local->rx_queue, skb);
rxrpc_wake_up_io_thread(conn->local);
}
return 0;
default:
WARN_ON_ONCE(1);
return -EPROTO;
}
}
/*
* set up security and issue a challenge
*/
static void rxrpc_secure_connection(struct rxrpc_connection *conn)
{
if (conn->security->issue_challenge(conn) < 0)
rxrpc_abort_conn(conn, NULL, RX_CALL_DEAD, -ENOMEM,
rxrpc_abort_nomem);
}
/*
* Process delayed final ACKs that we haven't subsumed into a subsequent call.
*/
void rxrpc_process_delayed_final_acks(struct rxrpc_connection *conn, bool force)
{
unsigned long j = jiffies, next_j;
unsigned int channel;
bool set;
again:
next_j = j + LONG_MAX;
set = false;
for (channel = 0; channel < RXRPC_MAXCALLS; channel++) {
struct rxrpc_channel *chan = &conn->channels[channel];
unsigned long ack_at;
if (!test_bit(RXRPC_CONN_FINAL_ACK_0 + channel, &conn->flags))
continue;
ack_at = chan->final_ack_at;
if (time_before(j, ack_at) && !force) {
if (time_before(ack_at, next_j)) {
next_j = ack_at;
set = true;
}
continue;
}
if (test_and_clear_bit(RXRPC_CONN_FINAL_ACK_0 + channel,
&conn->flags))
rxrpc_conn_retransmit_call(conn, NULL, channel);
}
j = jiffies;
if (time_before_eq(next_j, j))
goto again;
if (set)
rxrpc_reduce_conn_timer(conn, next_j);
}
/*
* connection-level event processor
*/
static void rxrpc_do_process_connection(struct rxrpc_connection *conn)
{
struct sk_buff *skb;
int ret;
if (test_and_clear_bit(RXRPC_CONN_EV_CHALLENGE, &conn->events))
rxrpc_secure_connection(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_see_conn_work);
ret = rxrpc_process_event(conn, skb);
switch (ret) {
case -ENOMEM:
case -EAGAIN:
skb_queue_head(&conn->rx_queue, skb);
rxrpc_queue_conn(conn, rxrpc_conn_queue_retry_work);
break;
default:
rxrpc_free_skb(skb, rxrpc_skb_put_conn_work);
break;
}
}
}
void rxrpc_process_connection(struct work_struct *work)
{
struct rxrpc_connection *conn =
container_of(work, struct rxrpc_connection, processor);
rxrpc_see_connection(conn, rxrpc_conn_see_work);
if (__rxrpc_use_local(conn->local, rxrpc_local_use_conn_work)) {
rxrpc_do_process_connection(conn);
rxrpc_unuse_local(conn->local, rxrpc_local_unuse_conn_work);
}
}
/*
* post connection-level events to the connection
* - this includes challenges, responses, some aborts and call terminal packet
* retransmission.
*/
static void rxrpc_post_packet_to_conn(struct rxrpc_connection *conn,
struct sk_buff *skb)
{
_enter("%p,%p", conn, skb);
rxrpc_get_skb(skb, rxrpc_skb_get_conn_work);
skb_queue_tail(&conn->rx_queue, skb);
rxrpc_queue_conn(conn, rxrpc_conn_queue_rx_work);
}
/*
* Input a connection-level packet.
*/
bool rxrpc_input_conn_packet(struct rxrpc_connection *conn, struct sk_buff *skb)
{
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
switch (sp->hdr.type) {
case RXRPC_PACKET_TYPE_BUSY:
/* Just ignore BUSY packets for now. */
return true;
case RXRPC_PACKET_TYPE_ABORT:
if (rxrpc_is_conn_aborted(conn))
return true;
rxrpc_input_conn_abort(conn, skb);
rxrpc_abort_calls(conn);
return true;
case RXRPC_PACKET_TYPE_CHALLENGE:
case RXRPC_PACKET_TYPE_RESPONSE:
if (rxrpc_is_conn_aborted(conn)) {
if (conn->completion == RXRPC_CALL_LOCALLY_ABORTED)
rxrpc_send_conn_abort(conn);
return true;
}
rxrpc_post_packet_to_conn(conn, skb);
return true;
default:
WARN_ON_ONCE(1);
return true;
}
}
/*
* Input a connection event.
*/
void rxrpc_input_conn_event(struct rxrpc_connection *conn, struct sk_buff *skb)
{
unsigned int loop;
if (test_and_clear_bit(RXRPC_CONN_EV_ABORT_CALLS, &conn->events))
rxrpc_abort_calls(conn);
switch (skb->mark) {
case RXRPC_SKB_MARK_SERVICE_CONN_SECURED:
if (conn->state != RXRPC_CONN_SERVICE)
break;
for (loop = 0; loop < RXRPC_MAXCALLS; loop++)
rxrpc_call_is_secure(conn->channels[loop].call);
break;
}
/* Process delayed ACKs whose time has come. */
if (conn->flags & RXRPC_CONN_FINAL_ACK_MASK)
rxrpc_process_delayed_final_acks(conn, false);
}
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