1 files changed, 270 insertions, 0 deletions

diff --git a/net/rxrpc/krxsecd.c b/net/rxrpc/krxsecd.c
new file mode 100644
index 000000000000..6020c89d9228
--- /dev/null
+++ b/net/rxrpc/krxsecd.c
@@ -0,0 +1,270 @@
+/* krxsecd.c: Rx security daemon
+ *
+ * Copyright (C) 2002 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.
+ *
+ * This daemon deals with:
+ * - consulting the application as to whether inbound peers and calls should be authorised
+ * - generating security challenges for inbound connections
+ * - responding to security challenges on outbound connections
+ */
+
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/completion.h>
+#include <linux/spinlock.h>
+#include <linux/init.h>
+#include <rxrpc/krxsecd.h>
+#include <rxrpc/transport.h>
+#include <rxrpc/connection.h>
+#include <rxrpc/message.h>
+#include <rxrpc/peer.h>
+#include <rxrpc/call.h>
+#include <linux/udp.h>
+#include <linux/ip.h>
+#include <net/sock.h>
+#include "internal.h"
+
+static DECLARE_WAIT_QUEUE_HEAD(rxrpc_krxsecd_sleepq);
+static DECLARE_COMPLETION(rxrpc_krxsecd_dead);
+static volatile int rxrpc_krxsecd_die;
+
+static atomic_t rxrpc_krxsecd_qcount;
+
+/* queue of unprocessed inbound messages with seqno #1 and
+ * RXRPC_CLIENT_INITIATED flag set */
+static LIST_HEAD(rxrpc_krxsecd_initmsgq);
+static DEFINE_SPINLOCK(rxrpc_krxsecd_initmsgq_lock);
+
+static void rxrpc_krxsecd_process_incoming_call(struct rxrpc_message *msg);
+
+/*****************************************************************************/
+/*
+ * Rx security daemon
+ */
+static int rxrpc_krxsecd(void *arg)
+{
+        DECLARE_WAITQUEUE(krxsecd, current);
+
+        int die;
+
+        printk("Started krxsecd %d\n", current->pid);
+
+        daemonize("krxsecd");
+
+        /* loop around waiting for work to do */
+        do {
+                /* wait for work or to be told to exit */
+                _debug("### Begin Wait");
+                if (!atomic_read(&rxrpc_krxsecd_qcount)) {
+                        set_current_state(TASK_INTERRUPTIBLE);
+
+                        add_wait_queue(&rxrpc_krxsecd_sleepq, &krxsecd);
+
+                        for (;;) {
+                                set_current_state(TASK_INTERRUPTIBLE);
+                                if (atomic_read(&rxrpc_krxsecd_qcount) ||
+                                    rxrpc_krxsecd_die ||
+                                    signal_pending(current))
+                                        break;
+
+                                schedule();
+                        }
+
+                        remove_wait_queue(&rxrpc_krxsecd_sleepq, &krxsecd);
+                        set_current_state(TASK_RUNNING);
+                }
+                die = rxrpc_krxsecd_die;
+                _debug("### End Wait");
+
+                /* see if there're incoming calls in need of authenticating */
+                _debug("### Begin Inbound Calls");
+
+                if (!list_empty(&rxrpc_krxsecd_initmsgq)) {
+                        struct rxrpc_message *msg = NULL;
+
+                        spin_lock(&rxrpc_krxsecd_initmsgq_lock);
+
+                        if (!list_empty(&rxrpc_krxsecd_initmsgq)) {
+                                msg = list_entry(rxrpc_krxsecd_initmsgq.next,
+                                                 struct rxrpc_message, link);
+                                list_del_init(&msg->link);
+                                atomic_dec(&rxrpc_krxsecd_qcount);
+                        }
+
+                        spin_unlock(&rxrpc_krxsecd_initmsgq_lock);
+
+                        if (msg) {
+                                rxrpc_krxsecd_process_incoming_call(msg);
+                                rxrpc_put_message(msg);
+                        }
+                }
+
+                _debug("### End Inbound Calls");
+
+                try_to_freeze(PF_FREEZE);
+
+                /* discard pending signals */
+                rxrpc_discard_my_signals();
+
+        } while (!die);
+
+        /* and that's all */
+        complete_and_exit(&rxrpc_krxsecd_dead, 0);
+
+} /* end rxrpc_krxsecd() */
+
+/*****************************************************************************/
+/*
+ * start up a krxsecd daemon
+ */
+int __init rxrpc_krxsecd_init(void)
+{
+        return kernel_thread(rxrpc_krxsecd, NULL, 0);
+
+} /* end rxrpc_krxsecd_init() */
+
+/*****************************************************************************/
+/*
+ * kill the krxsecd daemon and wait for it to complete
+ */
+void rxrpc_krxsecd_kill(void)
+{
+        rxrpc_krxsecd_die = 1;
+        wake_up_all(&rxrpc_krxsecd_sleepq);
+        wait_for_completion(&rxrpc_krxsecd_dead);
+
+} /* end rxrpc_krxsecd_kill() */
+
+/*****************************************************************************/
+/*
+ * clear all pending incoming calls for the specified transport
+ */
+void rxrpc_krxsecd_clear_transport(struct rxrpc_transport *trans)
+{
+        LIST_HEAD(tmp);
+
+        struct rxrpc_message *msg;
+        struct list_head *_p, *_n;
+
+        _enter("%p",trans);
+
+        /* move all the messages for this transport onto a temp list */
+        spin_lock(&rxrpc_krxsecd_initmsgq_lock);
+
+        list_for_each_safe(_p, _n, &rxrpc_krxsecd_initmsgq) {
+                msg = list_entry(_p, struct rxrpc_message, link);
+                if (msg->trans == trans) {
+                        list_del(&msg->link);
+                        list_add_tail(&msg->link, &tmp);
+                        atomic_dec(&rxrpc_krxsecd_qcount);
+                }
+        }
+
+        spin_unlock(&rxrpc_krxsecd_initmsgq_lock);
+
+        /* zap all messages on the temp list */
+        while (!list_empty(&tmp)) {
+                msg = list_entry(tmp.next, struct rxrpc_message, link);
+                list_del_init(&msg->link);
+                rxrpc_put_message(msg);
+        }
+
+        _leave("");
+} /* end rxrpc_krxsecd_clear_transport() */
+
+/*****************************************************************************/
+/*
+ * queue a message on the incoming calls list
+ */
+void rxrpc_krxsecd_queue_incoming_call(struct rxrpc_message *msg)
+{
+        _enter("%p", msg);
+
+        /* queue for processing by krxsecd */
+        spin_lock(&rxrpc_krxsecd_initmsgq_lock);
+
+        if (!rxrpc_krxsecd_die) {
+                rxrpc_get_message(msg);
+                list_add_tail(&msg->link, &rxrpc_krxsecd_initmsgq);
+                atomic_inc(&rxrpc_krxsecd_qcount);
+        }
+
+        spin_unlock(&rxrpc_krxsecd_initmsgq_lock);
+
+        wake_up(&rxrpc_krxsecd_sleepq);
+
+        _leave("");
+} /* end rxrpc_krxsecd_queue_incoming_call() */
+
+/*****************************************************************************/
+/*
+ * process the initial message of an incoming call
+ */
+void rxrpc_krxsecd_process_incoming_call(struct rxrpc_message *msg)
+{
+        struct rxrpc_transport *trans = msg->trans;
+        struct rxrpc_service *srv;
+        struct rxrpc_call *call;
+        struct list_head *_p;
+        unsigned short sid;
+        int ret;
+
+        _enter("%p{tr=%p}", msg, trans);
+
+        ret = rxrpc_incoming_call(msg->conn, msg, &call);
+        if (ret < 0)
+                goto out;
+
+        /* find the matching service on the transport */
+        sid = ntohs(msg->hdr.serviceId);
+        srv = NULL;
+
+        spin_lock(&trans->lock);
+        list_for_each(_p, &trans->services) {
+                srv = list_entry(_p, struct rxrpc_service, link);
+                if (srv->service_id == sid && try_module_get(srv->owner)) {
+                        /* found a match (made sure it won't vanish) */
+                        _debug("found service '%s'", srv->name);
+                        call->owner = srv->owner;
+                        break;
+                }
+        }
+        spin_unlock(&trans->lock);
+
+        /* report the new connection
+         * - the func must inc the call's usage count to keep it
+         */
+        ret = -ENOENT;
+        if (_p != &trans->services) {
+                /* attempt to accept the call */
+                call->conn->service = srv;
+                call->app_attn_func = srv->attn_func;
+                call->app_error_func = srv->error_func;
+                call->app_aemap_func = srv->aemap_func;
+
+                ret = srv->new_call(call);
+
+                /* send an abort if an error occurred */
+                if (ret < 0) {
+                        rxrpc_call_abort(call, ret);
+                }
+                else {
+                        /* formally receive and ACK the new packet */
+                        ret = rxrpc_conn_receive_call_packet(call->conn,
+                                                             call, msg);
+                }
+        }
+
+        rxrpc_put_call(call);
+ out:
+        if (ret < 0)
+                rxrpc_trans_immediate_abort(trans, msg, ret);
+
+        _leave(" (%d)", ret);
+} /* end rxrpc_krxsecd_process_incoming_call() */