--- /dev/null
+/* incoming call handling
+ *
+ * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/net.h>
+#include <linux/skbuff.h>
+#include <linux/errqueue.h>
+#include <linux/udp.h>
+#include <linux/in.h>
+#include <linux/in6.h>
+#include <linux/icmp.h>
+#include <linux/gfp.h>
+#include <net/sock.h>
+#include <net/af_rxrpc.h>
+#include <net/ip.h>
+#include "ar-internal.h"
+
+/*
+ * generate a connection-level abort
+ */
+static int rxrpc_busy(struct rxrpc_local *local, struct sockaddr_rxrpc *srx,
+ struct rxrpc_header *hdr)
+{
+ struct msghdr msg;
+ struct kvec iov[1];
+ size_t len;
+ int ret;
+
+ _enter("%d,,", local->debug_id);
+
+ msg.msg_name = &srx->transport.sin;
+ msg.msg_namelen = sizeof(srx->transport.sin);
+ msg.msg_control = NULL;
+ msg.msg_controllen = 0;
+ msg.msg_flags = 0;
+
+ hdr->seq = 0;
+ hdr->type = RXRPC_PACKET_TYPE_BUSY;
+ hdr->flags = 0;
+ hdr->userStatus = 0;
+ hdr->_rsvd = 0;
+
+ iov[0].iov_base = hdr;
+ iov[0].iov_len = sizeof(*hdr);
+
+ len = iov[0].iov_len;
+
+ hdr->serial = htonl(1);
+ _proto("Tx BUSY %%%u", ntohl(hdr->serial));
+
+ ret = kernel_sendmsg(local->socket, &msg, iov, 1, len);
+ if (ret < 0) {
+ _leave(" = -EAGAIN [sendmsg failed: %d]", ret);
+ return -EAGAIN;
+ }
+
+ _leave(" = 0");
+ return 0;
+}
+
+/*
+ * accept an incoming call that needs peer, transport and/or connection setting
+ * up
+ */
+static int rxrpc_accept_incoming_call(struct rxrpc_local *local,
+ struct rxrpc_sock *rx,
+ struct sk_buff *skb,
+ struct sockaddr_rxrpc *srx)
+{
+ struct rxrpc_connection *conn;
+ struct rxrpc_transport *trans;
+ struct rxrpc_skb_priv *sp, *nsp;
+ struct rxrpc_peer *peer;
+ struct rxrpc_call *call;
+ struct sk_buff *notification;
+ int ret;
+
+ _enter("");
+
+ sp = rxrpc_skb(skb);
+
+ /* get a notification message to send to the server app */
+ notification = alloc_skb(0, GFP_NOFS);
+ if (!notification) {
+ _debug("no memory");
+ ret = -ENOMEM;
+ goto error_nofree;
+ }
+ rxrpc_new_skb(notification);
+ notification->mark = RXRPC_SKB_MARK_NEW_CALL;
+
+ peer = rxrpc_get_peer(srx, GFP_NOIO);
+ if (IS_ERR(peer)) {
+ _debug("no peer");
+ ret = -EBUSY;
+ goto error;
+ }
+
+ trans = rxrpc_get_transport(local, peer, GFP_NOIO);
+ rxrpc_put_peer(peer);
+ if (IS_ERR(trans)) {
+ _debug("no trans");
+ ret = -EBUSY;
+ goto error;
+ }
+
+ conn = rxrpc_incoming_connection(trans, &sp->hdr, GFP_NOIO);
+ rxrpc_put_transport(trans);
+ if (IS_ERR(conn)) {
+ _debug("no conn");
+ ret = PTR_ERR(conn);
+ goto error;
+ }
+
+ call = rxrpc_incoming_call(rx, conn, &sp->hdr, GFP_NOIO);
+ rxrpc_put_connection(conn);
+ if (IS_ERR(call)) {
+ _debug("no call");
+ ret = PTR_ERR(call);
+ goto error;
+ }
+
+ /* attach the call to the socket */
+ read_lock_bh(&local->services_lock);
+ if (rx->sk.sk_state == RXRPC_CLOSE)
+ goto invalid_service;
+
+ write_lock(&rx->call_lock);
+ if (!test_and_set_bit(RXRPC_CALL_INIT_ACCEPT, &call->flags)) {
+ rxrpc_get_call(call);
+
+ spin_lock(&call->conn->state_lock);
+ if (sp->hdr.securityIndex > 0 &&
+ call->conn->state == RXRPC_CONN_SERVER_UNSECURED) {
+ _debug("await conn sec");
+ list_add_tail(&call->accept_link, &rx->secureq);
+ call->conn->state = RXRPC_CONN_SERVER_CHALLENGING;
+ atomic_inc(&call->conn->usage);
+ set_bit(RXRPC_CONN_CHALLENGE, &call->conn->events);
+ rxrpc_queue_conn(call->conn);
+ } else {
+ _debug("conn ready");
+ call->state = RXRPC_CALL_SERVER_ACCEPTING;
+ list_add_tail(&call->accept_link, &rx->acceptq);
+ rxrpc_get_call(call);
+ nsp = rxrpc_skb(notification);
+ nsp->call = call;
+
+ ASSERTCMP(atomic_read(&call->usage), >=, 3);
+
+ _debug("notify");
+ spin_lock(&call->lock);
+ ret = rxrpc_queue_rcv_skb(call, notification, true,
+ false);
+ spin_unlock(&call->lock);
+ notification = NULL;
+ BUG_ON(ret < 0);
+ }
+ spin_unlock(&call->conn->state_lock);
+
+ _debug("queued");
+ }
+ write_unlock(&rx->call_lock);
+
+ _debug("process");
+ rxrpc_fast_process_packet(call, skb);
+
+ _debug("done");
+ read_unlock_bh(&local->services_lock);
+ rxrpc_free_skb(notification);
+ rxrpc_put_call(call);
+ _leave(" = 0");
+ return 0;
+
+invalid_service:
+ _debug("invalid");
+ read_unlock_bh(&local->services_lock);
+
+ read_lock_bh(&call->state_lock);
+ if (!test_bit(RXRPC_CALL_RELEASE, &call->flags) &&
+ !test_and_set_bit(RXRPC_CALL_RELEASE, &call->events)) {
+ rxrpc_get_call(call);
+ rxrpc_queue_call(call);
+ }
+ read_unlock_bh(&call->state_lock);
+ rxrpc_put_call(call);
+ ret = -ECONNREFUSED;
+error:
+ rxrpc_free_skb(notification);
+error_nofree:
+ _leave(" = %d", ret);
+ return ret;
+}
+
+/*
+ * accept incoming calls that need peer, transport and/or connection setting up
+ * - the packets we get are all incoming client DATA packets that have seq == 1
+ */
+void rxrpc_accept_incoming_calls(struct work_struct *work)
+{
+ struct rxrpc_local *local =
+ container_of(work, struct rxrpc_local, acceptor);
+ struct rxrpc_skb_priv *sp;
+ struct sockaddr_rxrpc srx;
+ struct rxrpc_sock *rx;
+ struct sk_buff *skb;
+ __be16 service_id;
+ int ret;
+
+ _enter("%d", local->debug_id);
+
+ read_lock_bh(&rxrpc_local_lock);
+ if (atomic_read(&local->usage) > 0)
+ rxrpc_get_local(local);
+ else
+ local = NULL;
+ read_unlock_bh(&rxrpc_local_lock);
+ if (!local) {
+ _leave(" [local dead]");
+ return;
+ }
+
+process_next_packet:
+ skb = skb_dequeue(&local->accept_queue);
+ if (!skb) {
+ rxrpc_put_local(local);
+ _leave("\n");
+ return;
+ }
+
+ _net("incoming call skb %p", skb);
+
+ sp = rxrpc_skb(skb);
+
+ /* determine the remote address */
+ memset(&srx, 0, sizeof(srx));
+ srx.srx_family = AF_RXRPC;
+ srx.transport.family = local->srx.transport.family;
+ srx.transport_type = local->srx.transport_type;
+ switch (srx.transport.family) {
+ case AF_INET:
+ srx.transport_len = sizeof(struct sockaddr_in);
+ srx.transport.sin.sin_port = udp_hdr(skb)->source;
+ srx.transport.sin.sin_addr.s_addr = ip_hdr(skb)->saddr;
+ break;
+ default:
+ goto busy;
+ }
+
+ /* get the socket providing the service */
+ service_id = sp->hdr.serviceId;
+ read_lock_bh(&local->services_lock);
+ list_for_each_entry(rx, &local->services, listen_link) {
+ if (rx->service_id == service_id &&
+ rx->sk.sk_state != RXRPC_CLOSE)
+ goto found_service;
+ }
+ read_unlock_bh(&local->services_lock);
+ goto invalid_service;
+
+found_service:
+ _debug("found service %hd", ntohs(rx->service_id));
+ if (sk_acceptq_is_full(&rx->sk))
+ goto backlog_full;
+ sk_acceptq_added(&rx->sk);
+ sock_hold(&rx->sk);
+ read_unlock_bh(&local->services_lock);
+
+ ret = rxrpc_accept_incoming_call(local, rx, skb, &srx);
+ if (ret < 0)
+ sk_acceptq_removed(&rx->sk);
+ sock_put(&rx->sk);
+ switch (ret) {
+ case -ECONNRESET: /* old calls are ignored */
+ case -ECONNABORTED: /* aborted calls are reaborted or ignored */
+ case 0:
+ goto process_next_packet;
+ case -ECONNREFUSED:
+ goto invalid_service;
+ case -EBUSY:
+ goto busy;
+ case -EKEYREJECTED:
+ goto security_mismatch;
+ default:
+ BUG();
+ }
+
+backlog_full:
+ read_unlock_bh(&local->services_lock);
+busy:
+ rxrpc_busy(local, &srx, &sp->hdr);
+ rxrpc_free_skb(skb);
+ goto process_next_packet;
+
+invalid_service:
+ skb->priority = RX_INVALID_OPERATION;
+ rxrpc_reject_packet(local, skb);
+ goto process_next_packet;
+
+ /* can't change connection security type mid-flow */
+security_mismatch:
+ skb->priority = RX_PROTOCOL_ERROR;
+ rxrpc_reject_packet(local, skb);
+ goto process_next_packet;
+}
+
+/*
+ * handle acceptance of a call by userspace
+ * - assign the user call ID to the call at the front of the queue
+ */
+struct rxrpc_call *rxrpc_accept_call(struct rxrpc_sock *rx,
+ unsigned long user_call_ID)
+{
+ struct rxrpc_call *call;
+ struct rb_node *parent, **pp;
+ int ret;
+
+ _enter(",%lx", user_call_ID);
+
+ ASSERT(!irqs_disabled());
+
+ write_lock(&rx->call_lock);
+
+ ret = -ENODATA;
+ if (list_empty(&rx->acceptq))
+ goto out;
+
+ /* check the user ID isn't already in use */
+ ret = -EBADSLT;
+ pp = &rx->calls.rb_node;
+ parent = NULL;
+ while (*pp) {
+ parent = *pp;
+ call = rb_entry(parent, struct rxrpc_call, sock_node);
+
+ if (user_call_ID < call->user_call_ID)
+ pp = &(*pp)->rb_left;
+ else if (user_call_ID > call->user_call_ID)
+ pp = &(*pp)->rb_right;
+ else
+ goto out;
+ }
+
+ /* dequeue the first call and check it's still valid */
+ call = list_entry(rx->acceptq.next, struct rxrpc_call, accept_link);
+ list_del_init(&call->accept_link);
+ sk_acceptq_removed(&rx->sk);
+
+ write_lock_bh(&call->state_lock);
+ switch (call->state) {
+ case RXRPC_CALL_SERVER_ACCEPTING:
+ call->state = RXRPC_CALL_SERVER_RECV_REQUEST;
+ break;
+ case RXRPC_CALL_REMOTELY_ABORTED:
+ case RXRPC_CALL_LOCALLY_ABORTED:
+ ret = -ECONNABORTED;
+ goto out_release;
+ case RXRPC_CALL_NETWORK_ERROR:
+ ret = call->conn->error;
+ goto out_release;
+ case RXRPC_CALL_DEAD:
+ ret = -ETIME;
+ goto out_discard;
+ default:
+ BUG();
+ }
+
+ /* formalise the acceptance */
+ call->user_call_ID = user_call_ID;
+ rb_link_node(&call->sock_node, parent, pp);
+ rb_insert_color(&call->sock_node, &rx->calls);
+ if (test_and_set_bit(RXRPC_CALL_HAS_USERID, &call->flags))
+ BUG();
+ if (test_and_set_bit(RXRPC_CALL_ACCEPTED, &call->events))
+ BUG();
+ rxrpc_queue_call(call);
+
+ rxrpc_get_call(call);
+ write_unlock_bh(&call->state_lock);
+ write_unlock(&rx->call_lock);
+ _leave(" = %p{%d}", call, call->debug_id);
+ return call;
+
+ /* if the call is already dying or dead, then we leave the socket's ref
+ * on it to be released by rxrpc_dead_call_expired() as induced by
+ * rxrpc_release_call() */
+out_release:
+ _debug("release %p", call);
+ if (!test_bit(RXRPC_CALL_RELEASED, &call->flags) &&
+ !test_and_set_bit(RXRPC_CALL_RELEASE, &call->events))
+ rxrpc_queue_call(call);
+out_discard:
+ write_unlock_bh(&call->state_lock);
+ _debug("discard %p", call);
+out:
+ write_unlock(&rx->call_lock);
+ _leave(" = %d", ret);
+ return ERR_PTR(ret);
+}
+
+/*
+ * handle rejectance of a call by userspace
+ * - reject the call at the front of the queue
+ */
+int rxrpc_reject_call(struct rxrpc_sock *rx)
+{
+ struct rxrpc_call *call;
+ int ret;
+
+ _enter("");
+
+ ASSERT(!irqs_disabled());
+
+ write_lock(&rx->call_lock);
+
+ ret = -ENODATA;
+ if (list_empty(&rx->acceptq))
+ goto out;
+
+ /* dequeue the first call and check it's still valid */
+ call = list_entry(rx->acceptq.next, struct rxrpc_call, accept_link);
+ list_del_init(&call->accept_link);
+ sk_acceptq_removed(&rx->sk);
+
+ write_lock_bh(&call->state_lock);
+ switch (call->state) {
+ case RXRPC_CALL_SERVER_ACCEPTING:
+ call->state = RXRPC_CALL_SERVER_BUSY;
+ if (test_and_set_bit(RXRPC_CALL_REJECT_BUSY, &call->events))
+ rxrpc_queue_call(call);
+ ret = 0;
+ goto out_release;
+ case RXRPC_CALL_REMOTELY_ABORTED:
+ case RXRPC_CALL_LOCALLY_ABORTED:
+ ret = -ECONNABORTED;
+ goto out_release;
+ case RXRPC_CALL_NETWORK_ERROR:
+ ret = call->conn->error;
+ goto out_release;
+ case RXRPC_CALL_DEAD:
+ ret = -ETIME;
+ goto out_discard;
+ default:
+ BUG();
+ }
+
+ /* if the call is already dying or dead, then we leave the socket's ref
+ * on it to be released by rxrpc_dead_call_expired() as induced by
+ * rxrpc_release_call() */
+out_release:
+ _debug("release %p", call);
+ if (!test_bit(RXRPC_CALL_RELEASED, &call->flags) &&
+ !test_and_set_bit(RXRPC_CALL_RELEASE, &call->events))
+ rxrpc_queue_call(call);
+out_discard:
+ write_unlock_bh(&call->state_lock);
+ _debug("discard %p", call);
+out:
+ write_unlock(&rx->call_lock);
+ _leave(" = %d", ret);
+ return ret;
+}
+
+/**
+ * rxrpc_kernel_accept_call - Allow a kernel service to accept an incoming call
+ * @sock: The socket on which the impending call is waiting
+ * @user_call_ID: The tag to attach to the call
+ *
+ * Allow a kernel service to accept an incoming call, assuming the incoming
+ * call is still valid.
+ */
+struct rxrpc_call *rxrpc_kernel_accept_call(struct socket *sock,
+ unsigned long user_call_ID)
+{
+ struct rxrpc_call *call;
+
+ _enter(",%lx", user_call_ID);
+ call = rxrpc_accept_call(rxrpc_sk(sock->sk), user_call_ID);
+ _leave(" = %p", call);
+ return call;
+}
+
+EXPORT_SYMBOL(rxrpc_kernel_accept_call);
+
+/**
+ * rxrpc_kernel_reject_call - Allow a kernel service to reject an incoming call
+ * @sock: The socket on which the impending call is waiting
+ *
+ * Allow a kernel service to reject an incoming call with a BUSY message,
+ * assuming the incoming call is still valid.
+ */
+int rxrpc_kernel_reject_call(struct socket *sock)
+{
+ int ret;
+
+ _enter("");
+ ret = rxrpc_reject_call(rxrpc_sk(sock->sk));
+ _leave(" = %d", ret);
+ return ret;
+}
+
+EXPORT_SYMBOL(rxrpc_kernel_reject_call);
Code Review / kvmfornfv.git / blobdiff