diff options
Diffstat (limited to 'net/rxrpc/krxsecd.c')
-rw-r--r-- | net/rxrpc/krxsecd.c | 270 |
1 files changed, 270 insertions, 0 deletions
diff --git a/net/rxrpc/krxsecd.c b/net/rxrpc/krxsecd.c new file mode 100644 index 00000000000..6020c89d922 --- /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() */ |